Encapsulated cure systems

The present invention relates to adhesive and sealant compositions in which one or more reactive and / or curable or polymerizable components are encapsulated. In particular, the present invention relates to an encapsulated curing system for directly or indirectly initiating and / or performing curing or polymerization of an adhesive and sealant composition and a method for producing the same.

It is well known to use microencapsulated ingredients in the production of pharmaceuticals, pesticides, paints, adhesives, sealants and printing inks. Perhaps microcapsules are known to be most commonly used in products commonly referred to as carbonless papers, which are microencapsulated that are released when pressure is applied to the surface. Contains or is coated with a coating containing the ink and / or color former. The most well-known uses of microcapsules in the manufacturing and repair departments are adhesives and sealants. The use of microencapsulation makes it possible to turn two-component or higher adhesives and sealants into one-component adhesives and sealants. Microencapsulation also allows such adhesives and sealants to be pre-applied at the manufacturing or processing site rather than at the site where they are used or installed on the adherend. The use of microencapsulation in adhesives and sealants is well known and has gone through many different processes.

The encapsulated solvent-based adhesive system has various structures. Roesch et al. (US Pat. No. 5,922,798) describes a solvent-based adhesive system that is encapsulated with a solvent alone or with a resin dissolved in it and used to join two objects to be adhered, and is dissolved or softened by the solvent, respectively. It is taught. Eichel (US Pat. No. 2,907,682) discloses an adhesive tape, which includes a combination of an encapsulated solvent and an encapsulated solid adhesive soluble in that solvent. .. When the tape is applied to the adherend and pressure is applied, the capsule bursts and the solvent dissolves the adhesive, or at least makes the adhesive sticky, which forms an adhesive layer by evaporation or absorption of the solvent. A combination of a solvent and an adhesive material if the solvent is non-volatile, such as a plasticizer, and the adherend supporting the adhesive or the support to which the adherend is attached does not absorb the non-volatile solvent. Becomes a pressure-sensitive adhesive. Other cellulosic derivative-based adhesives such as polyvinyl acetate, rubber, nitrile rubber, ethyl cellulose or cellulosic acetate are particularly suitable for solvent active / reactivated applications.

Fused Deposition Modeling Adhesives Using Encapsulated Solvents are also well known. Baetzold et. Al. (US Pat. No. 6,084,010) teaches a solid, sticky or non-sticky hot melt adhesive composition in which the hot melt is softened or further tacked. Contains microcapsules of solvent that can be used. This heat-melt adhesive, usually in the form of a stick, is rubbed on the adherend to which it is applied to crush the capsules, release the solvent, soften the thermal melt and attach it to the surface of the adherend. ..

In the case of another type of encapsulated adhesive and sealant, the components of the adhesive or sealant material or the curable adhesive or sealant material are encapsulated in a single capsule. These capsules are usually contained in a binder system that is non-adhesive and dry to the touch, and is applied to the adherend. In this way a sticky or liquid flowable adhesive can be pre-applied, which is not activated until the capsule wall itself is crushed and the adhesive material is released or exposed, or the adhesive layer. Does not form. For example, Eichel (US Pat. No. 2,986,447) teaches the encapsulation of adhesive adhesives. Wallace (US Pat. No. 4,428,982) teaches the encapsulation of curable anaerobic adhesives, where the encapsulating material is air permeable, which allows the curable adhesive to be contained within the capsule until use. Is in a liquid or uncured state. Schwantes (US Pat. No. 6,592,990) teaches encapsulated adhesives, especially pressure-sensitive adhesives, which are formed in-situ after encapsulation of their components.

The third and most likely use in encapsulation of adhesives and sealants is to use curable or reactive adhesives and sealant compositions, which are curatives or hardeners. (curing Depending on the presence of agents) and / or crosslinkers and / or other reactants such as catalysts, initiators, accelerators, etc., the composition may be polymerized or cured to form the desired adhesive or sealant. However, one or more reaction components are encapsulated in this adhesive or sealant, separating them from the other components. There are many different types of these adhesives and sealant compositions, some of which are more typical, such as monomers, prepolymers and low molecular weight polymers or combinations thereof, epoxies, urethanes, unsaturated polyesters. , Alkyd and (Meta) Crylate are based. Such adhesives and sealant compositions are characterized by being formed as a system of two or more liquids, which are combined in an applicator during use. However, with the advent of encapsulation technology, it has become possible to encapsulate one or more reaction components and separate them from other components, producing one-component adhesives and sealant compositions with storage stability. Be done. For example, a curative or curing and / or cross-linking agent and / or other reactant is encapsulated and the capsule is dispersed in a liquid polymerizable monomer that forms a matrix of adhesive or sealant. Alternatively, the liquid-polymerizable component may be encapsulated and the curative or curing and / or cross-linking agent attached to the outer wall of the capsule or the liquid-polymerizable component may be encapsulated in the same manner.

These one-component adhesives and sealant compositions contain several different microcapsules, each of which is a curative or hardener and / or a cross-linking agent and / or one of other co-reactive components. Included alone or with other components of the adhesive or sealant composition. For example, in free radical polymerizable adhesives or sealant compositions, the system is as long as the oxidizing agent (typically peroxide) and reducing agent (typically amine and / or metallocene) are present in separate capsules. Stabilize. In this case, two different microcapsules may be used, each microcapsule containing a portion of the polymerizable component and one or more of the curing agents and / or co-reactants described above. Similarly, in the case of co-reactive polymerizable systems, the co-reactive species are encapsulated in separate microcapsules.

In the case of pre-applied adhesives and sealant compositions, it usually contains an encapsulating component in which the liquid adhesive or sealant composition is dispersed, the composition being applied to the adherend. A polymer film is formed on it, wrapping the liquid adhesive or sealant. This polymer film holds the liquid adhesive or sealant composition in place, forming a protective barrier and keeping the liquid adhesive or sealant composition dry to the touch. However, the curable or polymerizable components of the adhesive or sealant are not present in the encapsulated state, i.e. in the form of individual microcapsules.

A second aspect of pre-applied adhesives and sealants is that one or more of the adhesive or sealant components, especially liquid polymerizable components, are encapsulated in multiple microcapsules, which are liquid curable, polymerizable. Alternatively, it is dispersed in a hard enable binder system. In this embodiment, without encapsulating one or more solid activators, catalysts, initiators, accelerators, etc. for curing or polymerizing one or more solid curative or curing agents or encapsulated liquid polymerizable components. It may be dispersed in a binder. Separately, all components of the adhesive or sealant composition may be encapsulated in a number of different microcapsules dispersed in a liquid binder. In use, each of these modified binder systems is applied to the adherend to be bonded, cured or polymerized, and the microcapsules are bonded to the surface of the adherend. Suitable binder systems may or may not react with the composition during curing or polymerization of the adhesive or sealant composition. In most cases, the binder does not co-react, but instead acts as a filler in the polymerizable or curable composition.

Activation of these encapsulated adhesives and sealant compositions is carried out by crushing the microcapsules, which allows the liquid polymerizable component to come into contact with the curing agent, activator, catalyst and initiator. The mixing of these components is ensured by the flow generated by applying pressure to the adherends to be adhered or by relative movement between the adherends. Therefore, by limiting mixing, it is important that such systems have as much fluidity as possible to maximize mixing opportunities. The higher the viscosity, the harder it is to mix, and therefore only part of the curable material is cured. More importantly, the increased viscosity makes encapsulation difficult, if not impossible. Even if encapsulation is possible, the particle size of the capsule is an issue. Generally, when encapsulating a highly viscous liquid, microcapsules are obtained in which a large number of large particles and small particles are formed, or in which large particles and small particles are dispersed in a parabola.

The advent of such encapsulated adhesives and sealant compositions has greatly expanded and / or simplified the end applications in which this adhesive and / or sealant system is used, but what is lacking. Not without. Pre-applied adhesives or sealants are pre-applied, especially when unintended premature destruction of capsules is used in industrial manufacturing processes where the adhesive or sealant requires its rapid delivery and application, especially in pre-applied adhesives or sealants. This is the most common problem when the adherend to be bonded is similarly processed in such a manufacturing process and repeatedly handled or moved. Concerns about premature destruction, however, are not limited to the application and use of encapsulated adhesives. Premature destruction is during the storage and handling of microcapsules and, among other things, during the incorporation of encapsulated components into the adhesive or sealant matrix or, in pre-applied adhesives, the incorporation of the encapsulated adhesive system into the binder material. It is an important issue in the manufacture and processing of adhesives. The problem of premature fracture is significant in systems that are thixotropic, highly viscous, and / or incorporate fillers, especially granular fillers and fillers with sharp edges, or are exposed to high shear mixing and ejection processes. Become.

Increasing the thickness of the microcapsule wall is often done to overcome the problem of premature destruction. This is done especially with pre-applied adhesives and sealants, especially with screw locking or screw sealing pre-applied adhesives and sealants. This results in cell walls containing more than 30 weight percent, typically 10 to 20 weight percent of encapsulated ingredients, these one-component adhesives or 15 to 25 weight percent pre-applied during use. Nothing special with applied adhesives. However, the thicker the walls of the microcapsules, the less curable material is available for the same weight or volume of adhesive or sealant. Further, the amount of the curable material is reduced in the bond line for forming the adhesive surface or the sealing portion. Since the amount of the curable material is limited, the fluidity is insufficient and the surface of the adherend is insufficiently wetted. In addition, a large amount of shell wall debris, such as sand grains sandwiched between glass plates, creates a gap between the two objects to be adhered, which is difficult to fill due to the lack of curable material and low viscosity.

Further increase in the thickness of the microcapsule wall makes it difficult to break the wall when needed. Therefore, greater force is required to ensure the release of a corresponding amount of liquid curable or polymerizable component. The degree of destruction of the microcapsules is such that the thicker the capsule wall, the more pressure is applied, as the rupture of the capsule in such cases is usually caused by finger or hand pressure, pinch rollers and / or threading by threading members. If the amount of is not increased accordingly, it will be smaller. This is especially true in applications other than thread cutting where many rotations are utilized. Thus, in certain end applications, insufficient release of liquid curable or polymerizable components may result in poor or reduced sealing or adhesive strength, limiting the performance or applicability of such materials in certain applications. It ends up. Pre-applied adhesives or sealants also have a large amount of pre-applied adhesive or sealant to obtain the same adhesion or sealing capacity of the cured material due to the use of the liquid, as is often the case in the adhesion and / or sealing of threaded members. Required as opposed to agents and sealant compositions.

It is also known to incorporate hollow microspheres as "spacer" particles in the adhesive or sealant composition to alleviate the need for thicker capsule walls. For example, Hinterwaldner (US Pat. No. 4,362,566) employs hollow microspheres to enhance the storage stability of the adhesive and promote activation of the adhesive material and crushing of microcapsules in use. However, the addition of such microspheres results in the addition of yet another additive, which results in the same amount of adhesion or sealing without the use of large amounts of adhesive and sealant corresponding to the amount of microspheres. I can't.

<p num="0015"> Therefore, an encapsulated adhesive and sealant composition in which the thickness of the cell wall of the capsule is minimized and the amount of the liquid curable component is large is desired.</p><p num="0016"> It also has controlled flow properties, especially higher or higher viscosities than conventional encapsulated adhesives and sealant compositions, and has almost constant rheology, especially over a wide temperature range for use in crevices and liquid curing. Encapsulated adhesive and sealant compositions that can be used in other situations where rheological outflow is not desirable are needed.</p><p num="0017"> There is also a need for encapsulated adhesives and sealant compositions that can minimize the reaction or polymerization of curable or polymerizable components even in the event of unintended premature destruction or crushing of the capsule.</p><p num="0018"> Also, for certain applications, it is desired to achieve the above objectives without the use of components or materials that are not related to the adhesion and / or sealing of the adherend and its surface.</p><p num="0019"> There is also a need for adhesives and sealant compositions with one-component storage stability suitable for use in high speed industrial manufacturing processes.</p><p num="0020"> It is also desired to provide a prepolymer adhesive that can withstand a pre-applied state particularly to a predetermined adherend without being activated by a large pressure and force.</p><p num="0021"> The present invention provides a microencapsulated curing system for directly or indirectly initiating or performing curing or polymerization of an adhesive and sealant composition. In these microencapsulated curing systems, at least one curing agent and a carrier, in which the curing agent is dispersed as a separated phase, or a part or the whole of the curing agent is solubilized in the carrier or a carrier. Including a polymer shell that encapsulates the carrier, which is miscible with the carrier, the carrier is substantially impermeable in the absence of external forces. Carriers are solid or semi-solid, patty or gel-like materials that soften or flow at high temperatures, but soften or flow when exposed to liquid curable or polymerizable components of solids or semi-solids, adhesives or sealants at room temperature. It is preferable that the last two are combined so that they flow when a slight force is applied. In a preferred embodiment of the encapsulated curing system, the curing agent does not substantially or completely cure the curing composition until the curing agent and the curable composition to which it is added are homogeneously mixed.</p><p num="0022"> More specifically, the present invention relates to an encapsulated curing system for a curable composition, wherein the curing system includes (a) a carrier material, (b) a curative contained in the carrier material, and (c). ) Including a polymeric capsule that wraps the carrier material, the carrier is a natural or synthetic material or composition that is substantially impermeable without the application of external forces or exposure to high temperatures. The carrier material has (a) soft, patty or gel-like characteristics and (b) (i) is soluble in the liquid curable matrix component of the curable composition in which the carrier is used, or this matrix component. Softened by, (ii) the curable composition is cured or polymerized, and / or softened by environmental conditions, or (iii) the curative of the adhesive or sealant is curable, polymerizable or It is preferably a solid or semi-solid that is softened by the method or step of making it available for the crosslinkable component. In one embodiment, the carrier having patty or gel-like properties is a thixotropic or thickened composition comprising monomers, oligomers, prepolymers or combinations thereof. The object does not substantially react with the encapsulated curative. Alternatively, carriers that are or contain one or more thixotropic or non-thixotropy gelling agents or thickeners that are generated or latently act on or after encapsulation of the carrier material have also been performed. Among the various materials considered for carriers are thermal melts, pressure sensitive adhesives, rubber materials, elastomer / tackifier compositions, polymers with Tg &lt;35 ° C, semi-solid and solid resins, starches. And there are thickened or gelled materials of starch-based polymers, hydrogels, cold waxes, one or more monomers, oligomers, prepolymers or mixtures thereof. For certain applications, the carrier is preferably an adhesive or has latent adhesiveness. Requires force to flow or deform For these carriers, the force must be at least 1 psi. It is also preferred that the curative dispersed or entrained in the carrier is substantially immobile in the carrier and / or the capsule wall is substantially impermeable to the curative. It is particularly desirable that the curative and carrier be immobile with each other for ease of use and more uniform distribution, generally speaking, the curative is approximately 0.1 weight based on the total weight of the encapsulated curing system. It is present in an amount of percent to about 25 weight percent, and / or the shell constitutes about 0.8 weight percent to about 25 weight percent of the encapsulated curing system.</p><p num="0023"> In another aspect, the encapsulated curing system of the present invention comprises (a) a carrier material, (b) a curative contained in the carrier material, and (c) a polymer capsule wrapping the carrier material. Is a natural or synthetic material or composition that is substantially impermeable without external force or exposure to high temperatures and is encapsulated from a liquid carrier precursor composition in which the curative is dispersed or dissolved. Encapsulation is formed at the same time as or after.</p><p num="0024"> The present invention also relates to a method for preparing the encapsulated curing system. This method involves (1) encapsulation of non-liquid carrier particles containing a curing agent and (2) solid or viscous unless the curing agent is dispersed or dissolved at room temperature and / or high shear forces are applied. However, the encapsulation of a dispersion of heat-sensitive and / or shear-sensitive materials that becomes liquid or fluid when high temperatures and / or high shear forces are applied, and (3) the curing agent disperses or dissolves and consumes the curing agent. Such as encapsulation of a dispersion of liquid beads of a liquid precursor composition that cures or polymerizes without, and when consumed, without consuming all or substantially all of the curing agent. In the last method, the curing of the precursor composition occurs in-situ, simultaneously with or after the formation of the capsule wall. Such curing is performed entirely or partially by an encapsulated curing agent or preferably by another curing agent suitable for curing or polymerizing the polymerizable or curable component of the carrier precursor composition. It is said. Further, in the second and third methods described above, (a) latent gelation and / or thickener components, or containing such components, or (b) such gelation or in-situ. Materials or precursor compositions that form thickeners may be used. Such thickening or gelling agents may be temperature-dependent or time- and shear-dependent, or may react to form an in-situ gel.</p><p num="0025"> More specifically, the present invention relates to a method for producing an encapsulated curing system in which a curable composition is polymerized. (a) A step of uniformly dispersing or dissolving the curative in a monomer, oligomer and / or prepolymer composition that is substantially inactive with respect to the activator. (b) The step of forming microdroplets of the composition of step (a) and (c) The process of polymerizing these droplets and (d) Includes the step of encapsulating the polymerized droplets on a fragile polymeric material. There are various methods for forming the above-mentioned droplets, and examples thereof include precipitation polymerization, solution polymerization, suspension polymerization and dispersion polymerization.</p><p num="0026"> In another aspect, the method of the invention (a) A step of uniformly dispersing or dissolving the curative in a monomer, oligomer and / or prepolymer composition that is substantially inactive with respect to the activator. (b) The step of forming microdroplets of the composition of step (a) and (c) The step of encapsulating the droplets of the composition obtained in step (a) in the second polymerizable material, and (d) Including the step of polymerizing the second polymerizable material before or at the same time as the polymerization of the encapsulated droplets. Here the encapsulation applies coacervation, interfacial polymerization, air suspension, centrifugal extrusion, spray drying, pan coating or droplets of (a) to the dispersion of the second polymerizable material and pressure on this dispersion. It is done by applying a shock wave.</p><p num="0027"> In yet another aspect, the method for producing an encapsulated curing system of the present invention is: (a) A step of uniformly dispersing or dissolving the curative in a monomer, oligomer and / or prepolymer composition that is substantially inactive with respect to the activator. (b) The step of polymerizing the composition of step (a) and (c) The step of forming the composition of the polymerized step (a) into particles, and (d) Includes the process of encapsulating particles in a fragile polymeric material.</p><p num="0028"> Apart from this, the method of the present invention is (a) A step of uniformly dispersing the curative in the melt of this curative and non-reactive thermal material, (b) A step of preparing a dispersion, emulsion or suspension of this melt in a suitable liquid medium, and (c) The process of encapsulating the beads thus obtained in a fragile polymer material, and (d) Includes a step of lowering the temperature of the solution to cure the melt before, at the same time or after the encapsulation step.</p><p num="0029"> The present invention also relates to curable and polymerizable compositions comprising the encapsulated curable system described above. The curable and polymerizable composition may be in the form of a one-component liquid curable system having an encapsulated curable system dispersed in a liquid curable component. Separately, the curable and polymerizable composition may be a dry blend of encapsulated curable particles and encapsulated curable component particles. Further, the curable and polymerizable composition of the present invention may include a liquid binder containing a mixture of encapsulated curable particles and encapsulated curable and / or polymerizable component particles. The present invention also relates to an adherend having the pre-applied curable / polymerizable composition described above and a method for activating the curable / polymerizable composition.</p><p num="0030"> More specifically, the present invention comprises one or more of the curable or polymerizable monomers, oligomers and / or prepolymers described above and one or more of the encapsulated curatives of this encapsulated curative. At least one contains (a) a carrier material, (b) a curative contained in this carrier, and (c) a polymer capsule that wraps this carrier, unless the carrier material is exposed to external forces or high temperatures. A natural or synthetic material or composition that is substantially non-fluid. The carrier material has (a) soft, patty or gel-like characteristics and (b) (i) is soluble in the liquid curable matrix component of the curable composition in which the carrier is used, or by this matrix component. It is softened, (ii) the curable composition is cured or polymerized, and / or softened by environmental conditions, or (iii) the curative is curable, polymerizable or crosslinkable of the adhesive or sealant. It is preferably a solid or semi-solid that is softened by the method or process of making it available to the ingredients. Such carrier material may include one or more thixotropic or non-thixotropic gelling or thickeners, particularly slow-acting or naturally occurring, which coincide with the encapsulation of the carrier material. Alternatively, the encapsulation may occur in the carrier after that. Suitable curable or polymerizable monomers, oligomers and / or prepolymers are vinyl-polymerized, i.e. at least one vinyl group CH2 = CH- and / or reactive unsaturated (ie-C = C-). Unsaturated polyesters; urethanes; epoxy resins; polysulfides; isocyanates; silicones; polyethers, polyurethanes and polyolefins with silanol groups capable of undergoing silanol condensation or hydrosilylation reactions; And phenoxy resin and the like. In that preferred embodiment, the curative dispersed or entrained in the carrier is substantially immobile within the carrier, and / or the capsule wall is substantially impermeable to the curative and / or polymerizable component. ..</p><p num="0031"> The present invention also relates to such polymerizable compositions, wherein only one of the curatives required for polymerization, curing or cross-linking of the curable composition is contained in the encapsulated carrier and the other. The required curing agent is uniquely present on the surface of the adherend to which the composition is applied, which is dispersed or dissolved in the curable component. In yet another aspect, the curable composition comprises at least two different encapsulated curable systems, each containing a different carrier material and / or a different curative. A particularly important feature of the present invention is that even if the encapsulated curable capsule wall of the present invention is broken, the curative carried to the carrier is released or exposed to the curable component of the curable composition. It means that the curable component does not substantially polymerize, cure or crosslink until or as required for the remaining curative to carry out or activate the curing system. ..</p><p num="0032"> In yet another aspect, the invention relates to a curable composition that is pre-applied to an industrial or commercial stock material in the manufacturing industry, an adherend in the form of an article, the curable component thereof is also encapsulated. In such an embodiment, various encapsulated components are dispersed in a suitable binder for applying or retaining it on the adherend.</p><p num="0033"> The present invention also relates to an industrial or commercial stock material in the manufacturing industry, an object to be adhered in the shape of an article, to which the above-mentioned pre-applied curable composition is applied.</p><p num="0034"> In yet another aspect, the present invention employs the above-mentioned encapsulated curing system and a curable composition comprising the above-mentioned encapsulated curing system for an industrial bonding step.</p>

A wide variety of curing agents are preferably used in carrying out the present invention. Certain hardeners are curable or polymerizable Adhesives and / or the chemical properties of the sealant material, the properties and curing mechanism of the adhesive or sealant to be cured, the method and conditions under which the adhesive or sealant is polymerized or cured, adhesion It is selected according to the end use and / or properties of the adherend to which the agent or sealant is applied, the compatibility of the curing agent with the carrier, its precursor and / or the encapsulated material. One class of hardeners includes hardeners and hardeners and those with cross-linking of polymeric and prepolymer materials containing agents that initiate, promote or catalyze the cross-linking or solidification of these materials. Other types of curing agents include one or more polymerizable monomers, prepolymers and / including, for example, activators, co-activators, accelerators, co-promoters, catalysts, co-catalysts, initiators and co-initiators. Alternatively, those accompanied by polymerization of low molecular weight polymers, particularly those accompanied by free radical polymerization can be mentioned. Unless otherwise specified for convenience, "curative" and "hardener" as used herein and in the claims refer to all such agents. Specific examples of the various curatives will be described in detail below when describing the various adhesives and sealant systems that employ them.

Polymerizable, curable or crosslinkable adhesives and sealant compositions, of which curatives are suitable for use in carrying out the present invention, are also diverse. How a particular adhesive and sealant composition makes available the final application and environment in which it is applied, the curing mechanism adopted, and the curative for the curable, polymerizable or crosslinkable components of the adhesive or sealant. And selected according to the compatibility of the adhesive or sealant with the carrier used. Generally speaking, the present invention is applicable to most one-component and two- or more-component adhesives and sealant compositions as disclosed herein. Currently, encapsulation is not used in conventional one-component systems, but the present invention presents an object to be adhered that is exposed to conditions that initiate or cause polymerization or curing of the one-component system during treatment of the one-component system. Allows application to. For example, a thermosetting one-component adhesive or sealant is exposed to sufficient heat to initiate curing or polymerization of the one-component system during treatment of the adherend, but before the desired curing or polymerization takes place. It may be applied to the adhesive in advance. For convenience, unless otherwise stated, the term "curable composition" as used herein and in the claims means all curable, polymerizable and / or crosslinkable compositions. Similarly, the terms "curing," "polymerization," and "crosslinking" are used herein and in the accompanying claims, unless it is made clear that the following terms are not used in the traditional sense. Used as a compatible term in the scope of.

The carrier is the method and material used to prepare the capsule, the application in which the curing system is used, the chemistry and curative of the curable composition in which the carrier is used, the curability, polymerizable or cross-linking of the adhesive or sealant. One of a number of different materials is used, depending on the method of making it available for the sex component. Generally speaking, the carriers are (a) soluble in soft, patty or gel-like characteristics, or (b) (i) soluble in the liquid curable matrix component of the curable composition with which the carriers are used. Or softened by this matrix component, (ii) the curable composition is cured or polymerized, and / or softened by environmental conditions, and / or (iii) the curative is an adhesive or sealant. Are selected from natural and synthetic materials or compositions that are solid or semi-solid softened by methods or steps that make them available for curable, polymerizable or crosslinkable components of. The carrier may be substantially composed of a polymeric or oligomeric component and / or a monomeric component, although the carrier composition itself exhibits the characteristics described above. Further it should be understood that the curing systems of the present invention may contain a mixture of different encapsulated carriers, each containing the same or different curing agent. The carrier may be a thixotropy or a latent thixotropy, or one that causes them in-situ, however, due to the small particle size of the microcapsules, thixotropy can be used in compositions or materials containing carriers. Must be peculiar or peculiar. Conventional inorganic thixotropy additives such as fumed silica are now microencapsulated because the particle size of current inorganic thixotropic additives is larger than the particle size of microencapsulated cured systems. It is believed that it is not suitable for use in the preparation of hardened systems. Separately or additionally, the carrier composition may be a carrier immediately prior to or during the encapsulation process. Or the carrier precursor material is low viscosity and contains or from one or more thixotropic gelling agents or thickeners that become high viscosity after encapsulation and potentially act to generate in-situ. It may be configured. As used in this application and the appended claims, the terms "soft" and "patty-like" refer to the material to which these terms are attached to a medium force, usually at least 1 psi, preferably at least 5 psi. It means that it will not flow or deform unless force is applied. These soft, or patty-like materials may have no elasticity, or may have small or moderate elasticity, preferably when sufficient and repetitive force is applied to the encapsulated carrier. Has a consistency and modulus in the elastic range from elastic like cake frosting to elastic like bread dough so that more curatives in the carrier are exposed or available. .. Similarly, when referring to softening a carrier material, this means that the carrier material is exposed to, for example, the liquid component of a curable composition in which all or part of the carrier becomes soluble, miscible or swellable, or exposed to heat. In the case of carrier materials made of rubber or rubber, it means that they become soft, patty, or even more fluid when exposed to certain materials and / or conditions, such as being kneaded. It has a consistency and elastic modulus in the elastic range such as dough). Similarly, when referring to softening a carrier material, this means that the carrier material is exposed to, for example, the liquid component of a curable composition in which all or part of the carrier becomes soluble, miscible or swellable, or exposed to heat. In the case of carrier materials made of rubber or rubber, it means that they become soft, patty, or even more fluid when exposed to certain materials and / or conditions, such as being kneaded. It has a consistency and elastic modulus in the elastic range such as dough). Similarly, when referring to softening a carrier material, this means that the carrier material is exposed to, for example, the liquid component of a curable composition in which all or part of the carrier becomes soluble, miscible or swellable, or exposed to heat. In the case of carrier materials made of rubber or rubber, it means that they become soft, patty, or even more fluid when exposed to certain materials and / or conditions, such as being kneaded. It has a consistency and elastic modulus in the elastic range such as dough). Similarly, when referring to softening a carrier material, this means that the carrier material is exposed to, for example, the liquid component of a curable composition in which all or part of the carrier becomes soluble, miscible or swellable, or exposed to heat. In the case of carrier materials made of rubber or rubber, it means that they become soft, patty, or even more fluid when exposed to certain materials and / or conditions, such as being kneaded. It has a consistency and elastic modulus in the elastic range such as dough). Similarly, when referring to softening a carrier material, this means that the carrier material is exposed to, for example, the liquid component of a curable composition in which all or part of the carrier becomes soluble, miscible or swellable, or exposed to heat. In the case of carrier materials made of rubber or rubber, it means that they become soft, patty, or even more fluid when exposed to certain materials and / or conditions, such as being kneaded.

Examples of materials suitable for use as carriers are any of many low Tg materials such as thermal solutions, pressure sensitive adhesives, rubber materials and other low Tg materials, semi-solid and solid materials, starches and starches. Examples include based polymers, hydrogels and low temperature waxes, which satisfy one or more of the above characteristics and do not inhibit the curing or polymerization of the curable composition, or the desired cured, polymerized or crosslinked composition. It is a condition that the adhesiveness and sealing property of the polymer are not materially deteriorated.

Carriers are also commercially used to regulate the fluidity and fluid properties of organic and inorganic thixotropic thickening gelling agents, especially paints, adhesives, sealants, engine oils, industrial oils and foods. It may include what has been done. Suitable organic polymer thickeners or gelling agents include styrene / olefin block copolymers sold under the trade name "Kraton" and various plasticizers, thickeners, flow modifiers and the like. Various small molecules that are chemically or physically related can be mentioned. As mentioned above, conventional inorganic thixotropic agents, thickeners and gelling agents have very large particle sizes of the carrier material or carrier precursor beads to be encapsulated, unless their particle size is extremely small. Unless so, it is not preferred for use in the preparation of microencapsulated curing systems. However, it is not surprising that these materials will be available for the practice of the present invention as technology advances to enable the production of nano-sized inorganic thixotropic agents, thickeners and gelling agents. ..

On the other hand, the carrier or its components may be co-reactive with the curable composition and / or curative. For example, with respect to the curable composition, the carrier is a functional group that acts as a reaction or cross-linking site with the polymerizable monomer, prepolymer and / or polymer of the curable composition and during their polymerization or curing. May have. Separately and preferably, the carrier composition is (a) one or more liquid monofunctional and / or polyfunctional monomers, oligomers and / or prepolymers copolymerized by the liquid curable components of the curable composition. Mixtures (mixtures (a)) and (b) (i) slow-acting, latent gelling agents or thickeners, (ii) thermoactive gelling agents or thickeners (gelling at high temperatures). It may contain (not) and / or (iii) a viscosity modifier that is a shear-sensitive gelling agent or thickener. In this aspect, the carrier composition is in the encapsulation process in which the fine beads or droplets of the mixture (a) are prepared for encapsulation and return to high viscosity or become highly viscous and then exhibit the carrier properties described above. It is exposed to conditions that result in low viscosity, that is, conditions in which the viscosity modifier does not or substantially does not act. For example, the high temperature or shear forces that reduce viscosity may be removed after the formation of droplets and before, or simultaneously with, or subsequently with the application or deposition of the shell wall or shell wall forming material. Separately, after the formation of droplets, conditions that cause or promote the gelation or thickening of the emulsion, dispersion, suspension, colloid, etc. of the mixture (a) by latent gelation or thickener. May be exposed to. By adopting a carrier containing the mixture (a), the amount of liquid curable components in the final curable composition is minimized and the properties of the cured or polymerized curable composition are affected. The added benefit is that the amount of potential other inactive ingredients and / or other ingredients can be minimized.

When the carrier is a thickener, gelling agent or thixotropic agent, the viscosity at the time of bead formation is that of an encapsulated curing system in which fine droplets are formed by low or moderate shear forces. The viscosity is low enough to match the desired particle size and particle size distribution. In thickening, gelling or thixotropic states, its viscosity is fine at moderate to high shear forces, preferably in the preparation of substantially uniform droplets or very narrow, and the conventional bell curve particle size distribution The viscosity is such that it cannot be obtained.

Curatives are also involved in the polymerization of certain or all components of the carrier composition, but the amount of curative incorporated into the carrier precursor is an amount appropriate to cure the curable composition after the carrier polymerization is complete. The amount must be sufficient for the curative to remain. Preferably, the curing agent for the curable composition does not, or does not, contribute significantly to the curing or polymerization of the carriers. Instead, the carrier precursor composition comprises one or more other curing agents, leaving the encapsulated curing agent available for curing or polymerization of the curable composition. In any case, it is important that the curative incorporated into the carrier does not react with the carrier once formed and maintains the long-term storage stability and efficacy of the curative in the encapsulated carrier. Of course, curatives are most often involved in the chemical reaction between the carrier and the curable components of the curable composition. What is important here is that the curative does not react with the encapsulated carrier.

In addition, the carrier contains other components of the adhesive or sealant or other additives related to the carrier itself, such as plasticizers and / or adhesive resins to improve the flexibility or flexibility of the carrier. It may be included. However, it is also important here that such other components do not inhibit the curing or polymerization of the curable composition, or substantially provide the desired adhesiveness or sealing property of the cured, polymerized or crosslinked composition. It means that it will not deteriorate. Suitable plasticizers include phthalates, adipates, hydrocarbon resins, oils and fatty acid esters such as methyl palmitate and methyl stearate. Particularly preferred plasticizers are polybutene-based plasticizers as taught in Wyffels (US Pat. No. 5,688,850) and combinations thereof, or combinations thereof with other additives such as aliphatic lactic acid esters. Can be mentioned. Suitable adhesive resins include aliphatic and / or aromatic hydrocarbon resins and terpene resins.

The carrier may be an inert material from the point of view of adhesion and sealing, but it is preferred that the carrier itself is involved in the adhesion or sealing performance of the final adhesive or sealant into which it is incorporated. Specifically, in some cases, carriers are required to have inherent or potential adhesiveness or sealing properties. For example, the carrier may be a thickened or gelled paint containing a hot melt adhesive, a pressure sensitive adhesive, an elastomer / adhesive composition, one or more monomers, oligomers or mixtures thereof. It may contain any of. By adopting a carrier having adhesive properties, the carrier can immediately bond the two adhered objects to be adhered and hold the adhered bodies in a predetermined arrangement, and the curable composition is cured. Sufficient time can be given before polymerization or cross-linking. This is particularly useful in high speed industrial bonding applications where pressure can be applied to two objects to be bonded that are bonded in a very short time, such as a brief moment. This property occurs when the adherend to be adhered has a force due to being made of a product design and material that cannot be adhered, as it will separate without a momentary adhesive bond. This is especially important. For example, when bonding the opposing end flaps of a serial box that is easy to open when nothing is done, the use of carriers with adhesive properties allows the curable or polymerizable material to cure or polymerize for normal bonding. The flaps can be held together during the process.

The curing system of the present invention may contain a mixture of two or more different microencapsulated carriers, each containing the same or different curing agent and / or carrier material. For example, a carrier-contributive bond by adopting a combination of carrier particles, some containing a high proportion of potentially adhesive material and the rest containing a carrier material with low or non-adhesiveness. It may be one whose characteristics can be adjusted. Separately, some of the carrier particles may contain a gel containing a mixture of monofunctional and / or polyfunctional monomers copolymerized by the curable composition, and the rest may contain an adhesive. Such compositions provide limited rapid adhesion with more liquid curable components to enhance the performance of the adhesive composition while reducing the amount of non-reactive carriers. By using a mixture of substantially different carrier particles, the immediate and potential adhesiveness of the final adhesive composition can be balanced.

As already mentioned, the carrier material may be hydrogel. Suitable hydrogels include gelatins, polysaccharides, alginates, crosslinked polyacrylamide polymers, hydroxymethylmethacrylate polymers, crosslinked polyhydroxyethyl acrylates, polymerization crosslinked 2-acrylamide-2-methylpropanesulfonic acid polymers and From these salts, especially crosslinked polyvinylpyrrolidone, polyacrylic acid, copolymers of these and / or copolymers of these with other polymers such as polystyrene or other non-hydrogel forming polymers such as sodium and potassium salts. Some are induced. Examples of typical hydrogels include poly-2-hydroxyethyl methacrylate-based hydrogels, preferably poly-2-hydroxyethyl methacrylate-based hydrogels cross-linked with ethylene glycol dimethacrylate.

Further, the carrier may be an elastomer composition. Elastomers include those exhibiting a secondary glass transition point (Tg) or softening point below 25 ° C, preferably less than 0 ° C, especially those soluble in (meth) acrylate ester monomers. Such elastomers are synthetic polymeric compounds that exhibit plastic flow, especially copolymers of polychloroprene and butadiene or isoprene with styrene, acrylonitrile, and (meth) clearate esters. More useful elastomers include copolymers of ethylene and (meth) acrylate, homopolymers of epichlorohydrin and copolymers of epichlorohydrin and ethylene oxide. More specifically, with CR-neoprene-polychloroprene, NBR-nitrile rubber butadiene-acrylonitrile copolymer, styrene-butadiene copolymer, acrylic rubber acrylate butadiene copolymer, ethylene and acrylate esters such as methacrylate and ethyl acrylate. Examples thereof include the copolymer of. Not surprisingly, higher Tg material if the curable composition is activated at a higher temperature or is exposed to a higher temperature during activation, for example friction during mixing or if the mixer produces a higher temperature. May be used. Also included in this type of material are so-called rubber resin adhesives, which include elastomeric components such as natural rubber, styrene-butadiene elastomers, polybutadienes, polyisobutylenes and polysiloxanes, and glyceryl esters of hydride hydride. Includes adhesive resins such as thermoplastic terpene resins, petroleum hydrocarbon resins, kumaron inden resins, synthetic phenol resins, low molecular weight polybutene and adhesive silicone resins.

The carrier also has a low Tg or low softening point, preferably less than 25 ° C, and has a modulus of elasticity of 70 ° as measured using the dynamic mechanical thermal analyzer model number RSAII (available from Rheometrics). It may be an adhesive material or a pressure sensitive adhesive material that is less than about 5x105 dynes in C. Suitable as such an adhesive is an acrylate-based pressure-sensitive adhesive, particularly an adhesive that does not require the addition of an adhesive resin. Such acrylates contain an alkyl chain having 1 to 14 carbon atoms in the molecule, preferably 4 to 12 carbon atoms in the molecule. Mixtures of different acrylate monomers can also be used, but at least the carbon-carbon chains of at least four carbon atoms in which at least the majority of the alcohol residues forming the alkyl tails of the molecule terminate at the ester bond. Have. Examples of useful acrylate-based polymer materials include methyl isoamyl acrylate, isooctyl acrylate, and commercially available fuse oils. oil) homopolymers and copolymers of acrylate and 2-ethylhexyl acrylate. These copolymers may contain acrylic acid, methacrylic acid, acrylamide, methacrylamide, acrylonitrile and methacrylonitrile as comonomer. Other acrylic materials include low Tg acrylate monomers such as n-butyl acrylate, ethyl acrylate, 2-methylbutyl acrylate, isobutyl acrylate, isooctyl acrylate, and 2-ethylhexyl acrylate, and N, N-dimethyl (meth). Functional monomers such as acrylamide, N, N-diethyl (meth) acrylamide, N-vinylpyrrolidone, and 3,5-dimethyladamantyl (meth) crylate, isobornyl (meth) crylate, 4-biphenyl (meth) crylate and 2- There are multi-component compositions containing high Tg acrylate monomers such as nephtyl (meth) clearate. Another type of pressure-sensitive adhesive material is Mancinelli (US Pat. No. 5,225,470) acrylic Fused Deposition Modeling PSA, the contents of which are cited herein.

The present invention is particularly suitable for these carrier materials, particularly pressure sensitive adhesive materials that are in-situ polymerized, i.e., polymerized at the same time as or subsequently in the carrier encapsulation. Examples of such systems are those disclosed in, for example, Schwantes (US Pat. No. 6,592,990) and Nagai et. Al. Such systems are usually addition-polymerizable prepolymers such as alkyl (meth) clarate, aralkyl (meth) clarate, cycloalkyl (meth) clarate, alkoxy (meth) clarate, cycloalkoxy (meth) clarate, bicycloalkyl ( There are meta) clearate and alkoxy (alkoxy) n (meth) clearate. These alkyl moieties are selected from 1 to 16 carbon atoms, the cycloalkyl moieties are 4 to 8 carbon atoms, and n is an integer from 1 to 6.

More suitable addition-polymerizable prepolymers are prepolymers whose homopolymer has a Tg of less than 0 ° C, a flammability of at least 75 ° C and a boiling point of at least 175 ° C, such as n-pentyl acrylate, 2-methyl. Butyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, n-dodecyl acrylate, lauryl methacrylate, lauryl acrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, iso-octyl acrylate, iso-octyl methacrylate, iso Nonyl acrylate, isodecyl acrylate, 2-ethoxyethyl methacrylate, butyl diglycol methacrylate, tetrahydrofurfuryl acrylate, 2-phenoxyethyl acrylate, isohexyl acrylate, tridecyl acrylate, tridecyl methacrylate, ethoxylated nonylphenol acrylate and mixtures thereof. is there.

Optionally, the in-situ formed carrier may include a terpene resin in addition to the polymerizable prepolymer. The terpene resin functions as a tackifier, and suitable for achieving the object of the present invention include wood rosin resin, gum rosin ester, styrenated terpene and terpene phenol resin (CAS # 2590494-71-8). Including) and so on. Terpene resins include modified terpene resins commercially available under trade names Sylvares and Zontac (Arizona Chemical, located in Panama City, Florida) and ester-modified or polyol ester-modified products such as Sylvalite (CAS # 8050-26-8). There is terpene resin.

Optionally, the composition from which an in-situ formed carrier is obtained may comprise a second substantially water-insoluble, polyfunctional polymerizable prepolymer having at least two addition polymerization sites. .. By "substantially water insoluble" is meant that the substance is soluble in water in less than about 2 weight percent, preferably less than 1 weight percent. The addition polymerization site of this prepolymer interacts with other addition polymerization sites as the prepolymer transforms into an encapsulated adhesive adhesive material. Examples of a second substantially water-insoluble polymerizable prepolymer include allyl methacrylate, alkene glycol dimethacrylate, alkyl dimethacrylate, alkyldiol dimethacrylate, alkoxyalkanol diacrylate, trialkanol triacrylate, alkoxy (alkoxy) n. Alkyl triacrylate, alkoxy (alkoxy) n alkyl dimethacrylate, aralkyldimethacrylate, cycloalkyldimethacrylate, allyl acrylate, alkene glycol diacrylate, alkyldiacrylate, alkyldiol diacrylate, alkoxyalkanol dimethacrylate, trialkanol trimethacrylate, alkoxy Examples thereof include (alkoxy) n-alkyl trimethacrylate, alkoxy (alkoxy) n-alkyl diacrylate, aralkyldiacrylate, cycloalkyldiacrylate, alkoxydiacrylate, bicycloalkyldiacrylate, cycloalkoxydiacrylate, and the like. It has 1 to 16 carbon atoms, the cycloalkyl moiety has 4 to 8 carbon atoms, and n is an integer from 1 to 6. More specifically, the second substantially water-insoluble, polyfunctional polymerizable prepolymer having at least two addition polymerization sites is allyl methacrylate, triethylene glycol dimethacrylate, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate. Methacrylate, polyethylene glycol dimethacrylate, 1,

The second substantially water-insoluble polymerizable prepolymer may have at least three different mechanisms for forming an adhesive adhesive with the first prepolymer. The second polymerizable prepolymer may also have two reactive or polyfunctional sites for reacting with the first prepolymer. Separately, the second prepolymer is selected to have polar groups such as oxygen, amines, ethers, esters, alcohols, ketones, hydroxys, epoxys, carboxylic acids or arylic acids and is an adhesive-forming prepolymer. It may be hydrogen-bonded with other polar groups. In addition, a second prepolymer may be selected to sterically entangle or impede the movement of the opposing chains of the separately formed adhesive.

The second substantially water-insoluble polymerizable prepolymers with suitable polar groups are alkoxy (meth) crylate, polyester (meth) crylate, alkoxy (alkoxy) n alkyl (meth) clilate, (meth) krylalkoxyphthal. Selected from the group consisting of acids, glycidyl (meth) clearates, cycloalkoxy (meth) clearates and acyloxy (meth) clearates, these alkyl moieties have 1 to 16 carbon atoms and the cycloalkyl moieties have 4 to 8 carbon atoms. Of the number of carbon atoms, n is an integer from 1 to 6. Specific examples of this second substantially water-insoluble polymerizable prepolymer include butyldiethylene glycol methacrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl methacrylate, butyldiglycol methacrylate, t-butylaminoethyl methacrylate, 2- (2-oxoimidazolidine-1-yl-ethyl) methacrylate, tetrahydrofurfuryl methacrylate, tetrahydrofurfuryl acrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, glycidyl methacrylate, ethoxylated nonylphenol acrylate, ethoxylated hydroxyethyl methacrylate , Alkylated tetrahydrofurfuryl acrylate, ethoxylated nonylphenol methacrylate, alkoxylated nonylphenol acrylate, caprolactone acrylate, 2-acrylicoxyethoxy-o-phthalic acid, 2-acrylicoxy-1-methylethoxy-o-phthalic acid and 2-acrylic It is a substance selected from the group consisting of oxy-1-methylethoxy-o-dihydro- (3,6) -phthalic acid.

As mentioned above, the second substantially water-insoluble polymerizable prepolymer may be a prepolymer that sterically entangles or inhibits the movement of opposing chains of the adhesive-forming polymer. Such polymers include alkyl (meth) clearates with more than 14 carbon atoms, cycloalkyl (meth) clearates, polycyclic alkyl (meth) clearates, aralkyl (meth) clearates and cycloalkoxy (meth) clearates. , These alkyl moieties have at least 14 carbon atoms and the cycloalkyl moieties have at least 6 carbon atoms. Examples of substantially water-insoluble polymerizable prepolymers that sterically inhibit the first water-insoluble polymerizable prepolymer include stearyl acrylate, stearyl methacrylate, acrylate having 18 to 22 carbon atoms, and dicyclopentenyloxyethyl methacrylate. , Dicyclopentyloxyethyl methacrylate, isobornyl methacrylate, isobornyl acrylate, benzyl acrylate, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, cetyl acrylate and the like. Some of the substances identified early in carbon bond involvement, such as tetrahydrofurfuryl methacrylate, tetrahydrofurfuryl acrylate, 2-phenoxyethyl acrylate and 2-phenoxyethyl methacrylate, function as steric hindrance prepolymers. be able to.

To carry out carrier in-situ polymerization, carrier precursor compositions usually contain an effective amount of a substantially water-insoluble free radical initiator as a catalyst with the solvent in the presence of an addition-polymerizable prepolymer. Including. This solvent provides a medium for polymerizing various polymeric materials. Such a solvent may be a petroleum oil, a vegetable oil, a vegetable oil ester, a liquid hydrocarbon resin, a liquid plasticizer, or a mixture thereof. Free radical initiators are selected to have a half-life of at most 10 hours at 25 ° C, preferably at most 1 hour at 25 ° C. The free radical initiator must be soluble in the polymerizable prepolymer material and solvent. The free radical initiator is selected from the group consisting of initiators containing azo initiators, peroxides, dialkyl peroxides, alkyl peroxides, peroxy acid esters, peroxycarbonates, peroxyketones and peroxydicarbonates. can do. In particular, this free radical initiator is 2,2'-azobis (isobutylnitrile), 2,2'-azobis (2,4-dimethylpentanenitrile), 2,2'-azobis (2,4-dimethylvaleronitrile). ), 2,2'-azobis (2-methylpropanenitrile), 2,2'-azobis (methylbutyronitrile), 1,1'-azobis (cyclohexanecarbonitrile), 1,1'-azobis (cyanocyclohexane) ), Benoxyle peroxide, Decanonyl peroxide, Lauroyl peroxide, Benzoyl peroxide, Di (n-propyl) peroxydicarbonate, Di (sec-butyl) peroxydicarbonate, Di (2-ethylhexyl) perel Oxydicarbonate, 1,1-dimethyl-3-hydroxybutylperoxyneodecanoate, α-cumylperoxyneoheptanoeate, t-amylperoxyneodecanoate, t-butylperoxy Neodecanoate, t-amylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl2,

In another aspect of the invention, the carrier material may be heat sensitive, i.e., one that changes from a solid or semi-solid state to a liquid or patty when exposed to relatively low temperatures. Generally, such carriers have a melting point or melting range above room temperature (from 25 ° C) and are preferably curable at temperatures above or at least partially above the melting point or above the melting point. Soluble in the composition. Also preferably the dispersed phase has a melting point or range of 35 to 150 ° C, more preferably 40 to 85 ° C. Suitable heat-sensitive carrier materials include polyethylene glycols having a molecular weight of 4000 to 20,000; acidic waxes; stearic acid; stearates and the like. Particularly preferred is polyethylene glycol, which is a wax and has an average molecular weight of 4000. Other suitable materials are described in Cooke et. Al. (US Pat. Nos. 4,497,916 and 3,547,851), the contents of which are incorporated herein by reference.

Finally, other suitable carrier materials include Gosiewski et. Al. (US Pat. No. 5,206,288), Cahalan et. Al. (US Pat. No. 4,768,523), Sataki et. Al. (US Pat. No. 5,814,685), Everaerts et. Al. (US Pat. No. 5,905,099 and US Pat. No. 5,612,136), Mudge (US Pat. No. 4,908,268), Sanderson et. Al. (US Pat. No. 4,077,926), Mancinelli (US Pat. 5,006,582), Iovine et. Al. (US Pat. No. 4,721,748) and Petras et. Al. (US Pat. No. 4,061,826) include the core materials disclosed herein. It is assumed that

The curing system of the present invention comprises a polymer shell that wraps the carrier particles. Suitable materials for the formation of polymer shells are those known for encapsulation techniques, especially encapsulation of droplets or solid particles. Encapsulation materials are used in carrier precursor materials, including curatives, and in the encapsulation process for carriers that are in-situ cured or polymerized after or at the same time as the desired properties of the shell wall, the chemical composition of the carrier, and the formation of the shell. It is selected according to the method to be performed. It is also important that the composition of the shell wall is such that the shell wall is opaque to the curative, especially if the carrier is a composition that moves the curative within the carrier or blooms the curative from within the carrier. Is.

The shell wall may be a rigid or flexible material as long as it bursts under conditions that initiate polymerization, curing or cross-linking of the curable composition. For this purpose, the "initiation" or "initiation" of polymerization, curing or cross-linking referred to herein is the polymerization of a curable composition by curative, regardless of whether the polymerization, curing or cross-linking is actually carried out simultaneously. Means a step that comes into direct contact with a sex component or becomes available to a polymerizable component. For example, in an activated anaerobic curable composition, polymerization initiates, but does not occur because it is suppressed by oxygen in the presence of air. Similarly, the heat-activated curative is homogeneously mixed with the curable components of the curable composition, but no polymerization occurs until a temperature suitable for the heat-activated activity is obtained. Polymerization or curing initiates in the absence of substantially the physical or environmental conditions under which the adhesive is applied or the chemical co-reactant essentially provided by the adherend. To do.

The thickness of the shell wall can be of various thicknesses, from such a thickness that it has no or little structural effect and simply acts as an impermeable or low-permeability barrier to the curative. It can be as thick as it has structural connectivity. Such thin walls are particularly suitable for hardened systems where the carrier is a hard or rigid material. Separately, thicken the core wall if the microcapsules in the formulation or use of adhesives or sealants or the objects to which they are applied are exposed to a wide range of shear conditions, strong forces, and extreme handling. You may. Thick walls are also suitable if the carrier is very soft or thixotropic and provides itself little or less resistance to deformation.

Permeability is the ability of the shell wall to provide adequate protection against the entry and / or entry of substances into or from the microcapsules that adversely affect the shelf life of the microcapsules and / or the adhesive or sealant in which they are incorporated. Means. Thus, the shell wall may be permeable to certain substances for the usefulness and efficacy of the microcapsules during its predetermined life, usually 3 months, preferably 6 months or more, as long as it does not adversely affect it. ..

Generally speaking, an object of the present invention is to employ a thin shell wall, particularly a thinner shell wall used or found in current microencapsulated one-component adhesives. Yes, and of course, such thin shell walls are not required for current one-component adhesives, and traditionally thick shell walls are used. However, using a thin shell wall allows it to be present in a given amount of adhesive or adhesive site with more components required to form the adhesive or sealant and less inert filler represented by the shell wall. It is especially desirable because it does. Generally, in the present invention, the shell wall constitutes about 0.8 to 25 weight percent, preferably about 2 to 12 weight percent, and most preferably about 4 to 10 weight percent of the entire cured system.

The curing system of the present invention is prepared in two steps, the curative is incorporated into the carrier in the first step, and the modified carrier is encapsulated in the second step. Any number of methods of any kind can be used to carry out both of these steps, as will be readily apparent to those skilled in the art. However, a particular method is selected depending on many factors, such as when the materials used and the curative are incorporated into the carrier.

Curatives are incorporated into carriers in many different ways depending on the choice of curative and carrier material and the ability of the carrier material to be granulated and the method by which the carrier material is granulated. In one embodiment where the carrier is a solid or semi-solid material, if the curative is mixed or kneaded in the carrier and the resulting product has sufficient hardness, it is ground to the desired particle size and is not hard. If so, it is frozen and ground to the desired particle size. For example, the curative may be included in the polymer melt of the carrier, or if the carrier was a wax, it should be possible to mix the adsorbent with the liquid wax and solidify it. The curative may also be kneaded into a soft, flexible or malleable polymer or elastomer carrier using a roll mixer or banbury mixer. Any known method of incorporating a solid or semi-solid into another solid or semi-solid can be employed, provided that the treatment conditions do not substantially adversely affect or degrade the curative.

When the curative is in the form of a liquid or solution, the liquid curative or curative solution can use a solid or semi-solid carrier that absorbs or swells the solvent. In this method, the carrier acts more like a sponge, which allows the liquid curative to be absorbed into the carrier and, if in solution, the solvent to bring the curative into the carrier. When using a curative solution, preferably the solvent evaporates before encapsulation, or if the carriers after this evaporation are not in the proper particle shape, grind the carriers before encapsulation. However, the solvent of the curative solution acts as a plasticizer for the carriers, thus softening the carriers to curative without impairing the performance or desired characteristics of the cured adhesive or sealant or without decisive effects. It is not always necessary to remove the solvent or all solvents to promote proximity or curative exposure.

Alternatively, if the carriers themselves are in solution, the curative may be added to the solution before removing the solvent and recovering the denatured carriers. Also, depending on the nature of the carrier and carrier solution, the modified carrier may be precipitated using certain additives, pH adjustments and temperature changes.

Alternatively, another method of incorporating the curative into the carrier is to disperse or dissolve the curative, which is totally or partially soluble or miscible, in one or more of the precursor materials or reactants used to form the carrier material. There is a way. If curatives are also effective in initiating, accelerating, or accelerating the curing or polymerization of carriers, an excess of curative should be used to ensure that sufficient curing agent remains in the carriers after carrier formation. Must be. The reaction mixture may be cured or polymerized to form modified carriers and the resulting mass may be ground to a desired particle size. Alternatively, the reaction mixture described above or a component thereof may be added to a suitable liquid medium and shear-mixed to form a colloidal solution, suspension or emulsion. Colloidal solutions, suspensions or emulsions may be placed under conditions suitable for curing or polymerizing the reaction mixture to form modified carrier particles prior to encapsulation, or suitable encapsulation material. In addition to a solution suitable for encapsulating small droplets of the reaction mixture, capsules or shell walls may be formed with or without simultaneous polymerization or curing of the carrier material. Any known method of encapsulating the liquid, such as interfacial polymerization, coacervation, etc., can be used.

The amount of curative contained within the carrier is the specific curative used and the curable composition in which it is used, the method by which the curable composition initiates curing, the prediction of the encapsulated curable system of the curable composition. The weight ratio to be achieved, as described above, depends on whether the curative is involved in or is consumed by the hardening or polymerization of the carrier material and / or shell wall. Generally speaking, the amount of curative should match the amount used to cure a given curable composition. However, when homogeneous mixing, such as kneading or kneading, is performed in a manner in which the carriers and curable compositions are mixed, the curative is more efficiently exposed to the curable composition and therefore less in the same volume of curable composition. It may be possible to use a quantity of curative.

When the encapsulated curative is used in an addition polymerization curable composition, the curative contains from about 0.1 to 25 weight percent of the carrier, preferably from about 1 to 20 weight percent, most preferably from about 5 to 15 weight percent. Larger amounts are possible, but higher amounts reduce the amount of encapsulated carriers contained in the curable composition at a given particle size. Further, the higher the concentration of curative in the carrier particles and / or the larger the particle size of the carrier particles, the more in the curable composition (to maintain a predetermined amount of curative for a given amount of curable component). As the density of carrier particles in the curable composition decreases, it may be necessary to mix or knead the carrier particles more uniformly during the activation step to ensure that the curative in the curable composition is fully dispersed / distributed. ..

If the curative is a cross-linking or hardening agent commonly used in step-growth polymerization reactions, the amount of the curative in the microcapsules will be significantly higher. Typically, the curative will contain from about 2 to 50 weight percent of the carrier, preferably 10 to 30 weight percent, most preferably 15 to 25 weight percent. More importantly, the amount of these curatives will vary depending on the stoichiometric requirements for the curable composition and the degree of cross-linking required. Therefore, more or less curative may be used for the carrier by appropriately adjusting the amount of carrier particles incorporated into a predetermined amount of the curable composition.

Generally, the encapsulated carrier microparticles of the present invention function as microdomains of a highly concentrated amount of curing agent. If the curative also acts as a carrier and / or microcapsule wall curative, the curative is at least twice, preferably at least five times, the amount required to cure the carrier and / or wall material. Most preferably, it is contained in an amount of at least 10 times. In this case, the amount mentioned in the previous two paragraphs will be the amount after polymerization and / or curing of the carrier and / or cell wall, if necessary.

The particle size of the encapsulated curing system of the present invention varies depending on the intended end use, the method of initiating the curing of the curable composition, and the method of forming the particles. Generally, the volume weighted median particle size is in the range of about 2 to 200 microns, preferably about 5 to 50 microns, most preferably about 10 to 20 microns. The weighted median particle size is measured using Accusizer 788 manufactured by Particle Sizing Systems, Inc., located in Santa Barbara, California.

As mentioned above, microencapsulation of carrier material is achieved using any material via any known method. The following description is primarily about carrier encapsulation, but where the same is necessary or applicable as described below, especially other components of the curable composition, including liquid curable components. The same applies to the encapsulation of. Suitable methods for such encapsulation include coacervation, interfacial polymerization, suspension in air, centrifugal extrusion, spray drying, pan coating, in-situ polymerization and Redding Jr. (US Pat. No. 5,271,881, content). Is cited in the present specification), and there is a method of forming a dispersion of a core material and a shell material and applying a pressure shock wave to the dispersion. The method and material are selected depending on properties such as the physical state and / or chemical properties of the material to be encapsulated, eg, whether the carrier material is a liquid or solid or semi-solid or gel-like particle. Examples of methods and materials are those described in the following paragraphs and, for example, Schwantes (US Pat. No. 6,592,990), Nagai et. al. (US Pat. No. 4,708,924), Baker et. Al. (US Pat. No. 4,166,152), Wojciak (US Pat. No. 4,093,556), Matuskawa et. Al. 3,660,304), Ozono (US Pat. No. 4,588,639), Igarashi et. Al. (US Pat. No. 4,610,927), Brown et. Al. (US Pat. No. 4,552,811), Scher (US Pat. No. 4,285,720), Shioi et. . Al. (US Pat. No. 4,601,863), Kiritani et. Al. (US Pat. No. 3,886,085), Jahns et. Al. (US Pat. Nos. 5,996,051 and 5,292,835), Matson (US Pat. No. 3,516,941). , Chao (US Pat. No. 6,375,872), Foris et. Al. (US Pat. Nos. 4,001,140, 4,087,376, 4,089,802 and 4,100,103), Green et. al. (US Pat. Nos. 2,800,458 and 2,730,456), Clark (US Pat. No. 6,531,156), Saeki et. Al. (US Pat. Nos. 4,251,386 and 4,356,109), Hoshi et. Al. (US Pat. 4,221,710), Hayford (US Pat. No. 4,444,699), Hasler et. Al. (US Pat. No. 5,105,823), Stevens (US Pat. No. 4,197,346), Riecke (US Pat. No. 4,622,267), Greiner et. Al. (US Pat. No. 4,547,429) and Tice et. Al. (US Pat. No. 5,407,609) and Heribig, Kirk Othmer, Encyclopedia of Chemistry Technology, V. 13, Second Edition, pp. 436-456. A chapter entitled "Encapsulation" and "TAPPI, Vol. 49, No." published in May 1996 by Huber et. Al. The methods taught in "Capsular Adhesive" described in 41A-44A of "5" are mentioned, and all of these contents are cited in the present specification.

The first step in encapsulation is the preparation of discrete particles, domains or beads of carrier material or carrier precursor material. If the material is in solution or liquid form and encapsulation is performed by colloid, interfacial polymerization, etc., the solution or liquid containing the carrier or carrier precursor material is highly shear mixed or agitated to the desired particle size. Form suspensions, emulsions or colloidal systems of discrete domains of carriers or carrier precursors. If the carrier is a heat sensitive material, such as wax or waxy material, it is heated to a temperature above its melting point with the curative contained therein and is highly shear mixed or agitated in a liquid medium, preferably water. It is cooled to form discrete droplets of carrier and solid particles are formed prior to encapsulation. If the curative is incorporated into a solid or substantially solid carrier, the carrier is ground and sorted to the desired particle size prior to encapsulation. Such methods are widely used in the industry as well as yet another method of preparing particles or discrete domains for encapsulation and are well known to those of skill in the art.

One of the preferred microencapsulation techniques is coacervation, in which the material to be encapsulated is dispersed or emulsified in a solution of the material used as the wall material. The solution is perturbed to phase-separate the wall material or part thereof from a solvent containing the wall material coated with a dispersed material in which all or part is encapsulated. In this step, the wall forming material either separates directly onto the emulsified or dispersed core material or forms its own emulsion containing the wall material droplets, which are then deposited on the core material droplets. In either case, the liquid wall material deposits as a continuous coating around the dispersed droplets of the internal phase or capsule core material, after which the wall material solidifies. Disturbance of the solution affects the solubility of the wall material, such as temperature changes and the addition of another solvent that is non-solvent to the wall material, for example. This is the pH of a wall material such as gelatin to facilitate phase separation in the wall forming process as Green (US Pat. Nos. 2,800,457 and 2,800,458, the contents of which are cited herein) teaches. It should be well understood by those skilled in the art that it involves a shift.

In coacervation encapsulation, the material to be coated is usually a liquid, emulsified in a solvent to form droplets and coated with a wall material. In some cases, it may be advantageous to use an emulsifier to assist in the emulsification of the carrier material or its precursor. Preferred emulsifiers that can be used are amphipathic, i.e. containing both hydrophilic and hydrophobic groups in the same molecule. Examples of emulsifiers include partially hydrolyzed polyvinyl alcohol, starch derivatives, cellulosic derivatives, polyacrylamide and the like. The preferred emulsifier used in the present invention is partially hydrolyzed polyvinyl alcohol. In a preferred method, the aqueous mixture is highly shear agitated to obtain a particle size of less than 250 microns, preferably less than 100 microns.

The conditions for encapsulation depend on the material or composition used for encapsulation and the choice of material to be encapsulated. The encapsulating material or composition has many different factors, such as the desired properties of the shell wall to be formed, the chemical composition and state of the material to be encapsulated, the simultaneous or subsequent hardening or polymerization of the shell wall. In the case of a carrier material to be polymerized, it is selected depending on the carrier precursor material such as curative and the method used for encapsulation. Desirable properties of the shell wall are strength, fragility and permeability, etc., with respect to the encapsulated hardening system, especially when it comes to curatives where the carrier is a composition that moves or blooms the curatives therein. Suitable materials for the capsule wall are natural materials such as gelatin, gum arabic, starch, sugar, cellac and rosin, cellulose derivatives such as ethyl cellulose and carboxymethyl cellulose, paraffin, tristea, polyvinyl alcohol, polyethylene, polypropylene, polystyrene, polyacrylamide. , Polymers such as polyether, polyester, polyamide, polybutadiene, polyisoprene, silicone, epoxy and polyurethane, formaldehyde resins such as reaction products of formaldehyde with phenol, urea and melamine and copolymers such as polyurethane copolyether. Melamine formaldehyde and polyvinyl alcohol are preferable wall materials, and the former is particularly preferable.

Dyes, pigments, fillers, plasticizers, crosslinkers, binders and other additives may also be incorporated into or applied to the capsule wall surface. An important parameter to keep in mind when prescribing wall materials is permeability. In general, the wall material needs to be at least low permeable to the material to be encapsulated. It is important that the capsule is non-permeable or has low permeability to the curative in the carrier to prevent loss of curative and premature polymerization of the curable composition. Similarly, it is important to prevent the curable component from entering the carrier particles for the capsule wall, which is impermeable to or has low permeability to the curable component of the curable composition. Depending on the encapsulated material, the wall material is formulated to have low permeability to certain gases, such as oxygen, or to liquids such as water, solvents such as toluene or tetrahydrofuran. May be desirable. The required transmittance varies depending on each system, but can be satisfied by careful selection of the wall material and the degree of cross-linking of the wall material.

As mentioned above, many different methods can be used to encapsulate the carrier material and other materials of the curable composition. One of the preferred methods is to in-situ polymerize the capsule wall material. In this method, the monomer or oligomer is dispersed on the material to be encapsulated, and a reactive species such as a comonomer or radical initiator, a curing agent, or the like is added, or polymerization is carried out by heat or ultraviolet irradiation. Optionally, the capsule wall material may be cross-linked by the addition of a cross-linking agent or heat treatment, UV irradiation, or radical initiator. The method of polymerization or cross-linking of the capsule wall material depends on the choice of wall material and the material to be encapsulated.

A preferred method of encapsulation when the walls of the microcapsules are composed of polyamide or polyurea is interfacial polymerization. Interfacial polymerization can be carried out by mixing the microencapsulated adhesive monomer with either the acid chloride or the isocyanate. The resulting mixture is emulsified with an emulsifier to give an oil-in-water emulsion. A polyfunctional amino compound is added to the emulsion to form a microcapsule wall around the microparticles of each oil. When the acid chloride is mixed with a polyfunctional amino compound, polyamide microcapsules are made and isocyanates are used to form polyurea capsules. Although the oil phase microcapsules are referred to here, the dispersed phase also means "domain", "beads" or "droplets".

The acid chlorides used in the present invention to make polyamide microcapsules are terephthaloyl chloride, isophthaloyl chloride, 1,3,5-benzenetricarboxylic acid chloride, sebacyldichloride, 4,4-sulfonyldi. Benoxyl chloride, 1,3-benzenedisulfonyl chloride, 1,4-benzenedisulfonyl chloride or a mixture thereof. A preferred acid chloride for use in the present invention is a mixture of isophthaloyl chloride and terephthaloyl chloride.

The isocyanate compounds used in the present invention to make polyurea microcapsules are 2,4- and 2,6-diisocyanate toluene, 4,4'-diisocyanate diphenylmethane, 1,3,5-trimethylbenzene. -2,4-Diisocyanate, 1,6-diisocyanate hexane, polymethylene polyphenyl isocyanate and polyisocyanate containing biuret, allophanate and carbodiimide groups.

Examples of polyfunctional amines that can be used in the present invention include ethylenediamine, diethiolentriamine, triethylenetetraamine, tetraethylenepentamine, 1,6 hexanediamine, polyethyleneimine and bis-hexamethylenetriamine.

Matson (US Pat. No. 3,516,941) teaches a polymerization reaction that dissolves an encapsulated material or core in an organic hydrophobic oil phase dispersed in an aqueous phase. The aqueous phase dissolves the aminoplast resin that forms the material that forms the walls of the microcapsules during polymerization. A dispersion of fine oil droplets is prepared by high shear stirring. The addition of an acid catalyst initiates polycondensation to form an aminoplast resin, thereby forming an aminoplast polymer insoluble in both phases. As the polymerization proceeds, the aminoplast polymer separates from the aqueous phase and deposits on the surface of the dispersed droplets of the oil phase, forming a capsule wall at the interface between the two phases, thus encapsulating the core material. Polymerization using amines and aldehydes is well known as aminoplast encapsulation. The formation of urea-formaldehyde, urea-resorcinol-aldehyde, and urea-melamine-formaldehyde capsules proceeds in the same manner. In interfacial polymerization, the material forming the capsule wall is contained in another phase, one in the aqueous phase and the other in the oil phase. Therefore, the polymer capsule shell wall is formed at the interface between the two phases, thereby encapsulating the core material. Interfacial polymerization is particularly useful for wall materials such as polyesters, polyamides and polyureas.

Gelatins, including gelatin and microcapsule wall materials, are well known and are commonly used in core selvation and phase separation encapsulation methods. One of the preferred methods of encapsulation with gelatin / gum arabic is to first emulsify the core material into a gelatin solution to obtain an oil-in-water emulsion. The system is then pH adjusted and diluted to coacervate gelatin / gum arabic. The capsules are then post-treated with a cross-linking agent such as formaldehyde, glutaraldehyde or other similar known compounds.

A wall material composed of melamine-formaldehyde is produced by first emulsifying the core material into a carboxymethyl cellulose solution or a poly (styrene-maleic anhydride) solution to obtain an oil-in-water emulsion. The emulsion is then mixed with a melamine-formaldehyde precondensation solution. This system is pH adjusted and heated to initiate polymerization of the precondensate into high molecular weight compounds. The presence of a carboxymethyl cellulose or poly (styrene-maleic anhydride) solution facilitates the deposition of polymerized melamine-formaldehyde on the surface of the core, thereby encapsulating the core. Another method is to polymerize melamine and formaldehyde in the presence of styrene sulfonic acid. Yet another preferred embodiment of the method of forming a melamine-formaldehyde resin wall uses polyacrylic acid and / or polyacrylic acid derivatives and emulsifiers to assist in the formation of oil emulsions in water. The emulsifier preferably has an HLB value of about 8-18.

Optionally, the wall material can be formed by free radical polymerization or free radical cross-linking. It is particularly useful for wall materials such as polyvinyl chloride, polystyrene, acrylic acid esters (eg alkyl acrylate-acrylic acid copolymers), unsaturated polyesters and the like. Free radical reactions can be performed by heat, UV irradiation or by benzoyl peroxide, t-amylperoxyneodecanoate, t-amylperoxypivalate, t-amylperoxy-2-ethyl-hexanoate, t-butylperoxyisobutyrate. , T-amylperbenzoate, di-t-butyl peroxide, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2 It is started by adding an initiator such as'-azobis (2-methylpropanenitrile).

If the walls of the microcapsules are composed of epoxides, suitable epoxide compounds are vinylcyclohexene dioxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, bis-phenol-A-diglycidyl ether. Bifunctional or polyfunctional epoxides such as. One convenient method for forming microcapsules is to form an emulsion of the material to be encapsulated, then add a combination of bi- or polyfunctional epoxide and polyol to coat the material to be encapsulated and acid. Is added to carry out polymerization to form a peroxide. Suitable acids in this case are Bronsted acids such as hydrochloric acid or sulfonic acids and Lewis acids such as boron trifluoride and antimony pentafluoride.

The encapsulated curing system of the present invention offers many benefits and advantages for encapsulating adhesives or sealants not found or possible in conventional encapsulated systems. In particular, as mentioned above, the carrier may include materials with unique or potential adhesive properties that provide dual-mode adhesion and sealing in use. Even if the carrier itself does not perform any particular action, it acts as a structural filler that gives the adhesive or sealant material additional strength or durability, thus increasing the film tensile strength of the adhesive or sealant. Become. This is the result of the way the carriers and curable compositions are in contact with the polymerizable component of the adhesive or sealant, as a result of their unique properties and / or the way in which the curable composition is initiated and / or the curative is contacted with the polymerizable component of the adhesive or sealant. This is especially noticeable when it forms an interpenetrating network, or is otherwise interspersed or miscible with each other. The substantially curable composition will eventually fill the voids, grooves or pockets of the carrier.

The above are certainly beneficial and desirable properties, but a more important function of the carrier is other encapsulated ingredients used as protective reservoirs of curatives and in or with curable compositions. It is to play a role as a spatial protective substance of. First, the curative or sufficient amount of curative does not come into contact with the polymerizable component, even in the absence of an encapsulating shell, because the curative is incorporated into the carrier and preferably does not move within it. Instead, it imposes conditions that put the carrier in a fluid state, and / or mechanically functions through the force of crushing or kneading, where the carrier is repeatedly applied according to preferred embodiments, to provide more incorporated curative to the carrier surface and Must be exposed to a liquid curable composition. Therefore, as described below and except as described below, acupressure and pinch roller activation performed with conventional encapsulated adhesives and sealant systems is sufficient to produce proper curing or polymerization. Insufficient to expose the curative of. This requires more costly or sophisticated equipment to initiate more action and perhaps curing, which makes this adhesive and sealant a more stressful environment and process and / or desired. Alternatively, it means that sufficient force can be used in applications acting on the encapsulated adhesive prior to the intended start or timing of activity. It may also be concerned or concerned about how these microcapsules are formulated into the adhesive or sealant composition and / or how the microcapsules or the formulated adhesive and sealant composition are dispersed or applied. It means less. Accordingly, the present invention is used in industrial applications where these types of encapsulations, in particular pre-applied encapsulated adhesives and sealant compositions, are carried out at high speeds, especially when required by micro-adhesives or pre-applied adhesives. The intention to destroy the capsule wall at an early stage

In addition to preventing the release of curative during the unintended premature destruction of the shell wall of curative microcapsules, the curing system of the present invention provides a film in which one or more liquid components are encapsulated or pre-applied and encapsulated. It also acts as a spacer and protector for other encapsulated components of the curable system that is covered. Of course, the carrier has structural connectivity to the microcapsules, so when used, the microcapsules behave like conventional microspheres and contain micro-curable compositions or other liquid components. It can prevent premature disintegration or crushing of capsules. This property allows the curable composition or at least the encapsulated curable system according to the invention to be stacked during storage or handling, or to come into contact with other adherends and pressure the microcapsules, including carriers and curatives, to adhere. It is especially beneficial when pre-applied to the body. Although the structural bondability or resistance to deformation of the carrier material in addition to the structural bondability of the capsule wall covering the carrier material can protect the microcapsules containing the liquid polymerizable or curable component of the curable composition. Of course, the particle size of the microcapsules must be the same or smaller. Slightly larger particles if the capsule wall has sufficient elasticity to allow the encapsulated hardened particles to accept the initial pressure without bursting before being subjected to the original load of pressure or force acting on the pre-applied adhesive. Even a diameter encapsulated curable composition is acceptable. Even if a part of the capsule containing the liquid polymerizable or curable component and / or the carrier of the curable composition ruptures, the curative is carried into the carrier as described above, so that sufficient curing or polymerization is started. There are not enough curatives available to do this.

This spatial protection advantage is not limited to pre-applied adhesives, but is related to the formulated adhesives and the encapsulated curing system itself as well as their storage and handling stability. The shell wall and, more importantly, the structural connectivity of the microcapsules obtained from the carriers make the microcapsules less likely to break or crush prematurely. Furthermore, as mentioned above, the cell wall itself has little structural binding or strength, but rather, depending on the carrier material, the structural binding of the encapsulated cured microcapsules is the encapsulated carrier itself. It is due to. In such situations, curatives within the carrier are not available, so there is little concern about premature crushing or destruction of the cell wall. Concerns about the packaging, handling and container capacity of the encapsulated curable systems and the curable compositions in which they are incorporated are largely eliminated. In the former case, the encapsulated curing systems support each other. In the latter case, the encapsulated curing system supports and withstands the load of other capsules in the formulated composition. In the event of earlier crushing or destruction, the curative contained within the carrier is not lost and the carrier particles are simply reencapsulated as needed.

Yet another usefulness of the encapsulated curable system of the present invention is that when they are homogeneously mixed with the liquid polymerizable component of the curable composition, the carrier itself makes the liquid curable component available in addition to making the curative available. Is to provide a thickening and / or thixotropic effect to this liquid curable component. This thickening effect reduces the easiness of squeeze out or the possibility of squeeze out between the two objects to be adhered to which the curable composition is applied. More importantly, the liquid curable composition is used when there is a gap when the porous adherend, the adherend with a rough or non-uniform surface, or the two adherends to be adhered together. It means that you can do it. Specifically, this thickening effect of the liquid curable component makes it easier for the activated curable composition to stay in the place where it is surely applied. It also allows the curable composition to be applied as beads or raised ridges, thus reliably filling or bridging existing gaps. Conventional liquid adhesives can also be applied as beads, but their height cannot be maintained due to their low viscosity. Instead, the liquid bead forms a flat, tape-like liquid bead that is easy to spread. The beads of the present invention maintain their initial height, but are difficult to flow and allow more time to fit the adherends to be adhered. Even a thick adhesive bead, virtually like a scoop of ice cream, slowly shrinks and spreads.

In the present invention, high viscosity or thick beads can be formed after or at the same time as the homogeneous mixing of the components. For example, as described below, the active mechanism or device used to mix the components moves the curable composition back and forth as the adherend to which the curable composition is applied passes through the active mechanism or device. It may be a series of dams or barriers that are pushed or kneaded, or may include them. This device acts like a snowplow that leaves the bead or "bank" of the homogeneously mixed curable composition on the adherend as it exits the final dam or barrier. If a handheld or automated dispenser containing a mixing means is used separately, the dispenser may include an orifice, from which the homogeneously mixed curable composition is continuous. Or discontinuously. Curable compositions activated for the thickening or gelling effect of substantially carrier particles can be applied to adherends of virtually any type of appearance.

As mentioned above, the encapsulated curable system of the present invention can be used with many curable compositions, and the encapsulated curable system curative is a polymerizable or curable component of the curable composition. Appropriately selected for the curing or polymerization mechanism used to perform curing, polymerization and / or cross-linking. In this regard, the curative in any one microencapsulated carrier represents all the components of the curative or hardener required to complete the curing, polymerization or cross-linking of any curable composition. It should be understood that it does not have to be. Thus, the microencapsulated curing system referred to by the applicant of the present invention is all curatives required to cure, polymerize or crosslink the curable components of the curable composition and one or more required. It is to be interpreted as including an encapsulated carrier containing the curative of. Further important in this situation is that one or more curatives or hardeners are separated from one or more other required curatives or hardeners.

Thus, the curable compositions made according to the invention may contain one or more of the required curatives dispersed or dissolved therein, but these may be non-encapsulated curatives contained in the carrier. Do not co-react in the presence. Separately or in addition to this, one or more of the curatives may be dispersed or dissolved therein, especially if one or more of the curable components of the curable composition are encapsulated. Even if they do not react in the absence of the encapsulated curative contained in the carrier. Yet another embodiment comprises a plurality of microencapsulated curing systems made according to the teachings of the present invention, each comprising a different curative in the carrier. A preferred requirement for these possible embodiments is that all curatives required to cure, polymerize and / or crosslink the curable composition are present in the formulated curable composition, thereby all. Curing, polymerization, when curatives become available to each other and to the curable components of the curable composition, and optionally suitable environmental conditions, such as elevated temperatures or the absence of oxygen, are met. And / or cross-linking occurs. However, in the case of a metal adherend, certain curatives important for polymerizing, curing or cross-linking metal salts or metal oxides are present on the surface of the adherend to which the compositions of the present invention are applied. Alternatively, the curative may be pre-applied to the adherend as a primer, eg, a curative solution of a solvent carrier may be used to undercoat or coat the curative to the adherend. I want to be understood.

Generally speaking, the encapsulated curing system of the present invention is basically one-component, two-component or higher with any curable or polymerizable component, especially any adhesive or sealant component. It is possible to use liquid-based or liquid-based or tactile-dried pre-applied systems, especially those in which liquid-curable or polymerizable matrix monomers, prepolymers and / or polymers are encapsulated. In all applications, a more important factor is necessary to properly break the hardened shells that are sensitive or reliably encapsulated in the application and ensure that the carrier-carried curative is available. Is it possible to adapt to the treatment or functioning of the alleged adhesive composition? Peeling exposes some of the curative present on the outer surface of the carrier, but the amount of curative available is sufficient to cure, polymerize and / or crosslink the curable composition using it. Not enough to do it properly at the right level. Instead, the carrier minimizes release or exposure to the remaining or at least the components of the composition required to mix or knead, or at least cure or polymerize the curable composition of the curative contained therein. Must be exposed to some other conditions that limit it.

As already mentioned, the encapsulated curing system of the present invention is suitable for use in a wide variety of one-component liquid curing systems. In conventional encapsulated systems, there have been concerns about premature crushing and / or polymerization of curable compositions due to high shear during preparation and / or ejection of liquid curable compositions. However, in the encapsulated curing system of the present invention, the novel carrier system reduces the risk of premature crushing and / or polymerization. Not surprisingly, high shear forces during adhesive preparation and / or ejection do not provide sufficient amounts of curative to initiate premature polymerization or curing. On the other hand, in the case of these new systems so effective, the application and / or assembly process in which the liquid curing system is used is suitable to make the curative available to carry out or initiate the polymerization of the curable composition. It is desirable and necessary to provide the opportunity or means. For example, the curable composition of the present invention is suitable for use in bonding or sealing threaded members that are subjected to multiple rotations during the assembly process. Assemblies and press / snap fitting assemblies that are assembled without full rotation of the screws exert a large shear force on the adhesive surface, but such assemblies or applications are not recommended. The use of the present invention is also limited if pinch rolls or acupressure rupture the capsule wall, making curative available. Such a small effect that acts substantially on the carrier is insufficient to release or make available a suitable amount of curative necessary to perform a complete or substantial cure or polymerization of the curable composition. Is. However, the carrier is a wax and the liquid curable composition, including the encapsulated curing system, is hot enough to melt the wax before or at the same time as applying pressure and / or combining the two objects to be adhered. The exception is the encapsulated curing system to be exposed or the encapsulated curing system in which the carrier is a thixotropic material.

A more typical and practical use of the encapsulated curing system of the present invention is any of the common types of pre-applied adhesives mentioned above. The more difficult curative or curative tactile advantage and the protective or spacer advantage of the encapsulated curable system of the present invention are demonstrated in these applications. However, as mentioned above, it is possible to provide a suitable means by which the application or assembly process in which the encapsulated curing system is used makes available curatives in the carrier to polymerize or initiate the polymerization of the curable composition. is important.

Unlike the liquid curable compositions described above, which are applied and cured in use, pre-applied adhesives and sealants are utilized in the manufacture or processing of the adherend to which they are applied, and these adhesives and sealants are curable. It is not cured for some time due to the storage stability and storage stability of the composition and due to the requirements of the stock material or adherend to which the composition is applied. Generally, the stock material or adherend to which the adhesive and sealant are applied are stacked one after the other or placed in a container in which they come into contact with each other, and / or have the opportunity to be exposed to many different forces and pre-applied. Used in applications or assembly operations where there are other objects to be adhered that come into contact with the material. Carriers that make suitable curatives available for premature polymerization, curing or cross-linking of curable compositions if the encapsulated curable capsule or shell wall ruptures as a result of such force or action. Shearing and mixing will be inadequate. In a pre-applied adhesive that further comprises an encapsulated curing system dispersed in a liquid polymerizable component, the curing system is further between the adherend to which it is applied and the cured polymer film or layer overlaid on it. If sandwiched and the thickness of the layer of liquid adhesive is less than the particle size of the encapsulated curing system, the encapsulated curing system acts as a spacer to prevent the polymer film from collapsing and / or crushing. Similarly, in the more general pre-applied encapsulating adhesive system where the liquid curable component is also encapsulated, the average particle size of the encapsulated liquid component is smaller than the average particle size of the encapsulated curing system, the same. Or, if slightly larger, the encapsulated curing system acts as a spacer and prevents the disintegration or crushing of microcapsules containing liquid curable components. The latter feature is particularly useful as it allows the use of thinner capsules or shells traditionally used for encapsulation of liquid components. This also means that more liquid curable ingredients than conventional encapsulated adhesive and sealant compositions of the same volume.

Another advantage of the encapsulated curing system of the present invention is that the user can adjust the curative to a particular end application and control the curing rate even for the same curing system. is there. For example, if the carrier is wholly or partially soluble in the liquid component of the curable composition, is miscible, or is swellable by this liquid component, its solubility or swelling is curative in the carrier. Affects the exposure of. Similarly, the ease of kneading the carrier also determines the rate at which the curative is available for the curable liquid. In some encapsulated curing systems, the rate or time at which the adhesive or sealant system containing the curative is mixed also affects the degree and rate of close contact of the curative and curable liquid. If it contains curative predetermined amount of carrier, more particulates by mixing faster and / or longer Ratibu is exposed to the curable liquid, thus promoting the accelerated and / or thorough cure or polymerization curing. Mixing more slowly or shorter results in less interaction and slower curing.

As mentioned above, the encapsulated curing system of the present invention is useful for directly or indirectly initiating and / or curing or polymerizing the adhesive and sealant compositions. This curing or polymerization is carried out by addition polymerization, step-growth polymerization or both. Addition polymerization includes free radical polymerization, cationic polymerization, anionic polymerization and the like. Particularly preferred free radical polymerization systems are anaerobic adhesives and sealants, that is, those that polymerize or cure in the absence of air.

Generally speaking, suitable curable compositions are suitable or applicable to those known to date or to the following one-component (ie, single package) encapsulating adhesives and sealant compositions. Including everything that is. The composition is a curable composition that is storage stable, contains one or more components that are separated from other components via encapsulation, and polymerizes or cures without encapsulation. The curable composition comprises a curative contained in a carrier according to the present invention and a liquid or viscous component of an adhesive or sealant composition. In carrying out the present invention, this liquid or viscous component does not change its physical state or layer, and if it is not and until it is mixed with the curative, and where appropriate, conditions suitable for polymerization. It remains liquid or viscous until exposed to.

The liquid or viscous component of the curable composition is a single package dry type adhesive and sealant system containing a dry blend of components that are usually microencapsulated by themselves, or the encapsulated component is dispersed in a liquid binder system. It may be similarly encapsulated by a liquid adhesive or sealant system that is pre-applied to the adherend by a binder system that has been hardened or hardened or hardened. The curable composition may also be a single package wet type adhesive or sealant in which the encapsulated carriers are dispersed in a liquid or viscous curable material. Most of the time so far we have referred to liquid curable components or liquid adhesives or sealant compositions, but it should be understood that this also includes fluid and / or non-fluid viscous materials and compositions. Similarly, until the liquid or viscous component is exposed to curative, there is no substantial change in the physical state or phase of the liquid curable component, but the liquid or viscous composition further cures the liquid or viscous composition in the liquid or viscous state. Alternatively, as long as it is in the phase, it may contain or be a compound with an increasing viscosity. Generally, liquid or viscous polymerizable or curable components are in the form of low molecular weight monomers, oligomers and / or prepolymers.

Among these various curable compositions, those suitable for carrying out the present invention are, for example, those that polymerize vinyl, that is, at least one vinyl group CH2 = CH- and / or reactive unsaturated (-C). Those having = C-), unsaturated polyesters, urethanes, epoxy resins, polysulfides, isocyanates, silicones, polyethers having silanol moieties capable of undergoing silanol condensation or hydrosilylation reactions, polyurethanes and polyolefins and phenoxy resins. The present invention is also applicable to a combination of the same or different types of curable compositions, regardless of whether they cure by the same or different mechanisms. In the latter case, the curative of each curable composition may be contained in the same or different encapsulated carriers. Also, especially when one curing mechanism of these curable compositions is a long-term secondary curing mechanism, the curative for the curable composition is encapsulated with a curable component for the other curable composition. It may be transformed into. Further, the curable compositions of the present invention can be cured or polymerized through two different curing mechanisms, that is, bi-modal curing or polymerization. This is especially seen in curable compositions in which one mechanism forms a linear polymer chain and the other mechanism crosslinks. In addition, the composition may include a copolymerizable polymer and / or a secondary polymerizable component that copolymerizes with the primary component or co-reacts with the secondary reaction site of the primary polymer.

These curable compositions are of low molecular weight reactive monomers, oligomers and / or prepolymers that can be cured or polymerized. The prepolymer formulation is an addition-copolymerizable monomer and / or oligomer, which is essentially a pre-adhesive and / or pre-sealant. The present invention is, of course, preferably available for step-growth polymerization in certain applications, but the requirement for proper stoichiometry of primary and solidifying agents or co-reactive components is their curability. It makes the use of the composition more difficult. Further, depending on the molecular size of the curing agent or co-reactive component, the composition may require more weight percent of carrier particles than the addition-polymerizable composition when the curative is a low molecular weight material. .. Therefore, the present invention is particularly applicable to addition-polymerizable compositions.

Preferred copolymerizable compositions are those to which vinyl is added, such as substituted styrenes such as styrene and alpha-methylstyrene, acrylamides, nitriles such as cyanoacrylate and metaacrylonitrile, vinylketones such as ethylvinylketone, vinyl. Vinyl esters such as acetate and vinyl propionate, olefins such as ethylene, propylene and isobutylene, halogenated olefins such as vinyl chloride and vinylidene chloride, diene monomers such as butadiene, isoprene and chloroprene and vinyl chloride-vinyl acetate These copolymers, such as polymers. Often, these components are preferably used in oligomeric form, where other reactions such as hydroxyl, amino, carboxyl, epoxies and similar groups allow the oligomer to remain unsaturated or further polymerize or crosslink. Contains sex moieties or functional groups. For example, a polystyrene oligomer having an amine functional group may be employed, which results in initial curing or polymerization at the amine functional group moiety, eg, at the same time as cross-linking with isocyanate or at the unsaturated site prior to the cross-linking.

Particularly preferred addition-polymerizable components are polyfunctional and monofunctional acrylates and methacrylate esters, i.e. one or more acryloyl (CH2 = C (R) COO-) and / or methacryloyl (CH2 = C (CH3) COO-) ends or Monomers, oligomers and prepolymers with pendant moieties. For convenience, the term "(meth) clearate" as used herein and in the claims means both acrylate and methacrylate versions of a particular monomer, oligomer and / or prepolymer (eg, "allyl (meth)". ) Crylate "indicates that both allyl methacrylate and allyl acrylate are possible). Such substances include a wide range of polymerizable compounds, such as by the reaction of polyester poly (meth) clearate, urethane and polyurethane poly (meth) clearate (particularly hydroxyalkyl (meth) clearate with polyisocyanate or urethane polyisocyanate). To be adjusted), methyl cyanoacrylate, ethyl cyanoacrylate, diethylene glycol di (meth) clearate, trimethylpropantri (meth) clearate, ethylene glycol di (meth) clearate, allyl (meth) clearate, glycidyl (meth) clearate, (Meta) Crylate Functional Silicone, Di-, Tri- and Tetraethylene Glycol Di (Meta) Crylate, Diproprene Glycol Di (Meta) Crylate, Polyester Glycol Di (Meta) Cryrate, Di (Pentamethylene Glycol) Di (Meta) Crylate, Ethylene Di (Meta) Cryrate, Neopentyl Glycol Di (Meta) Cryrate, Trimethylol Propanetri (Meta) Crylate, Ethanolized Bisphenol A Di (Meta) Crylate, Bisphenol A Di (Meta) Cryrate, Diglycerol Di (Meta) Crylate, tetraethylene glycol dichloroacrylate, 1, Examples thereof include 3-butanediol di (meth) clearate, neopentyldi (meth) clearate, trimethylolpropane tri (meth) clearate, polyethylene glycol di (meth) clearate and dipropylene glycol di (meth) clearate. Di- and polyacrylates and methacrylates, especially dimethacrylates, are generally preferred materials. Monofunctional acrylates, i.e. those containing only one acrylate group, can also be advantageously used. Typical monoacrylates are 2-methylhexyl (meth) crylate, 2-hydroxyethyl (meth) crylate, cyanoethyl (meth) crylate, 2-hydroxypropyl (meth) crylate, p-dimethylaminoethyl (meth) crylate. , Lauryl (meth) crylate, cyclohexyl (meth) crylate, tetrahydrofurfuryl (meth) crylate, chlorobenzyl (meth) crylate and glycidyl (meth) crylate. Not surprisingly, (meth) clearates or mixtures thereof and one or more (meth) clearate monomers, oligomers and / or prepolymers or derivatives thereof and other copolymers such as acrylonitrile and methacrylonitrile. A combination with a monomer can also be used. , Tetrahydrofurfuryl (meth) clearate, chlorobenzyl (meth) clearate and glycidyl (meth) clearate. Not surprisingly, (meth) clearates or mixtures thereof and one or more (meth) clearate monomers, oligomers and / or prepolymers or derivatives thereof and other copolymers such as acrylonitrile and methacrylonitrile. A combination with a monomer can also be used. , Tetrahydrofurfuryl (meth) clearate, chlorobenzyl (meth) clearate and glycidyl (meth) clearate. Not surprisingly, (meth) clearates or mixtures thereof and one or more (meth) clearate monomers, oligomers and / or prepolymers or derivatives thereof and other copolymers such as acrylonitrile and methacrylonitrile. A combination with a monomer can also be used.

(Meta) clearate is usually polymerized by a free radical reaction. Free radical polymerization initiators useful in carrying out the present invention include peroxides, hydroperoxides, peracid esters, peracids, peroxycarbonates, peroxyketones, azo compounds and redox initiators and derivatives thereof. .. Specific examples of these initiators include benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, dicumyl peroxide, decanonyl peroxide, lauroyl peroxide, di- (n-propyl) peroxide, and t-butyl peroxide. Oxide acetate, t-butyl perbenzoate, t-butyl peroxybenzoate, t-butyl peroxy acetate, di-t-butyl azodiisobutyronitrile, t-amyl peroxyneodecanoate, dichlorobenzoyl peroxide, methyl ethyl ketone hydroperoxide , T-butyl peroxide, t-amylperoxypivalate, t-amylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, di-sec-butylperoxydicarbonate, di- (2-ethylhexyl) ) Peroxydicarbonate, 1,1-dimethyl-3-hydroxybutylperoxyneocarbonate, α-cumylperoxyneoheptanoate, t-amylperoxyneodecanoate, t-amylperoxypivalate, t-butylperoxypi Valate, t-amylperoxy-2-ethylhexanoate, t-amylperoxyacetate, t-amylperbenzoate, di-t-butyl peroxide, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylpentanenitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'- Azobis (2-methylpropanenitrile), 1,1'-azobis (cyclohexanecarbonitrile), 1, For example, 1'-azobis (cyanocyclohexane). Particularly preferred initiators are peroxides, hydroperoxides, peracid esters and peracids, most preferred are benzoyl peroxide. Usually such initiators are present in an amount of about 0.01 to 10 percent, preferably about 0.5 to 3.0 percent, most preferably about 0.1 to 2 percent by weight of the component that is curable by free radical polymerization.

In addition to the initiator, these free radically polymerizable compositions further comprise an accelerator for free radical polymerization. Commonly known accelerators include amines and sulfimides. Tertiary amines such as N, N-dimethylparatoluidine, triethylenetetraamine, diethylenetriamine, N, N-dimethylaniline, N, N-diethylparatoluidine and N, N-diethylaniline and 3-oxo-2,3- Sulfimides such as dihydrobenz- [di] isothiazole-1,1-dioxide (saccharin) are particularly useful. Also useful accelerators include aldehyde-amine reactive organisms such as butyraldehyde-aniline and butyraldehyde-butylamine. However, the most preferred accelerators are metallocenes, particularly organometallic compounds known as ferrocene and organometallic polymers containing at least one metallocene, preferably ferrocene. Specific organometallic compounds are ferrocene, butylferrocene, titanocene and capricen. Accelerators are typically used in an amount of about 0.01 to 1.0 percent by weight of the component cured by free radical polymerization. However, those skilled in the art preferably use the tertiary amine when there is a concern that the tertiary amine may move into a specific system and / or application, particularly a curable binder system, or a UV curable binder system as described above. I am aware that it will be done.

Preferred class of (meta) clearate-based curable compositions suitable for use in carrying out the present invention are known as anaerobic adhesives and sealant compositions. Generally, these compositions contain or do not contain free radical polymerizable monomers, oligomers and / or prepolymers, free radical initiators and stabilizers or bans such as polyhydric phenols and quinones. And include. Particularly preferred polymerizable monomers, oligomers and prepolymers are 2-hydroxyethyl (meth) clearate, 2-hydroxypropyl (meth) clearate, mono-, di-, tree and tetra-ethylene glycol di (meth) clearate, trimethylol. Propanetri (meth) clearate, ethoxylated bisphenol A di (meth) clearate, polyester (meth) clearate and its derivatives, polyethylene glycol (meth) clearate and its derivatives, polyurethane (meth) clearate and its derivatives. Suitable quinones include hydroquinone, benzoquinone, naftaquinone, phenaftaquinone, anthraquinone and substitution compounds thereof. These inhibitors are present in the adhesive composition in very small amounts, usually about 10 to 1000 ppm, preferably about 50 to 500 ppm. The anaerobic composition may include a chelating agent such as beta-diketone, ethylenediaminetetraacetic acid and a sodium salt thereof. Anaerobic compositions are particularly suitable for applications where premature curing or polymerization of the curable component is a concern prior to bonding of the adherend.

The present invention also relates to a wide range of epoxy resins such as Docket et. Al. (US Pat. No. 3,746,068), Hart et. Al. (US Pat. No. 4,536,524), Earls et. Al. (US Pat. No. 5,510,431) and Siebert et. It is applicable to the types disclosed in al. (US Pat. Nos. 5,157,077 and 5,140,068), the contents of which are incorporated herein by reference. Generally speaking, suitable epoxy resins include a mixture of low molecular weight oligomers containing an average of two or more epoxide groups per molecule, but may also include these oligomeric polymers. The most common epoxy resins are glycidyl compounds, especially bisphenol A or resorcinol glycidyl ethers and, to a lesser extent, diglycidyl esters of phthalic acid, hexahydrophthalic acid and tetrahydrophthalic acid. Other suitable epoxy resins include novolac-epoxy resins, especially phenol novolac or cresol novolac, glycerol, polypropylene glycol or pentaerythritol glycidyl ethers, glycidyl esters, glucidylamines, epoxidized diene polymers and alicyclic epoxies. There are resins and the like.

The epoxy resin may be polymerized by treatment with a hardener or curing agent that reacts with the epoxy group. Suitable curing agents are aliphatic primary and secondary amines such as diethylenetriamine, triethylenetetraamine and diethylaminopropylene, m-phenylenediamine, aromatic amines such as 4,4''-diaminodiphenylmethane and diaminodiphenylsulfone, anhydrous. Amines, especially phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, maleic anhydride, pyromellitic anhydride, trimellitic anhydride, methylnadic anhydride, dodecenylacetic anhydride and chlorendic anhydride, and fatty acids. polyamide. Other suitable curing agents include dicyandiamide, melamine, imidazole derivatives, ethylene oxide epoxy resin adducts, acrylonitrile epoxy resin adducts and modified amines such as ketimine, Lewis acids such as boron trifluoride-monoethylamine complex, o- (diethylamino). There are Lewis bases such as ethyl) phenol, tris- (dimethylaminomethyl) phenol and 2-ethyl-4-methylimidazole. Many cation initiators such as HCl, HBr, HI, C6H5SO3H, HSbF6, HAsF6, HBF4 or Lewis acids such as metal halide salts may be used to chemically cure or polymerize the epoxy compound and resin. .. The amount of curing agent added depends on the curing agent used, but in the case of anhydrides, usually per epoxy stoichiometry or in the case of amines, 0.85 to 1.0 mol in stoichiometry or cation initiator for chemical curing. When used, about 0.01 to 10%, preferably about 0.1 to 3%, is added by weight of the curable epoxy. In the case of anhydrous, about 1 percent tertiary amine may be used as the catalyst. Those skilled in the art can easily determine the appropriate amount of hardener or catalyst to use.

In many cases, and preferably depending on the application, the epoxy prepolymer is reacted with a polyol, most preferably a polyester or a polyether polyol. Polyester polyols include chain and / or branched polyethers with multiple ether bonds and at least two hydroxyl groups. Specific examples of the polyether polyol include polyoxyalkylene polyols such as polyethylene ether glycol, polypropylene ether glycol, and polybutylene ether glycol. Suitable polyols are homopolymers and copolymers thereof, especially copolymers of polyoxyalkylene polyols. Particularly preferred polyoxyalkylene polyol copolymers are ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, 2-ethylhexandiol-1,3-glycerin, 1,2,6-hexanetriol, At least one compound selected from the group consisting of trimethylolpropane, trimethylolethane, tris (hydroxyphenyl) propane, triethanolamine, trimethylolethane, triisopropanolamine, ethylenediamine and ethanolamine and ethylene oxide, propylene oxide and butylene oxide. An adduct containing at least one compound selected from the group consisting of.

Polyester polyols are formed by condensation of one or more polyhydric alcohols with 2 to 15 carbon atoms and one or more polycarboxylic acids with 2 to 14 carbon atoms. Examples of suitable polyhydric alcohols include ethylene glycol, propylene glycol such as 1,2-propylene glycol and 1,3-propylene glycol, glycerol, pentaerythritol, trimethylolpropane, 1,4,6-octanetriol, butanediol. , Pentandiol, hexanediol, dodecanediol, octanediol, glycerol monoallyl ether, glycerol monoethyl ether, diethylene glycol, 1,3-bis- (2-hydroxyethoxy) -propane. Examples of polycarboxylic acids are phthalic acid, isophthalic acid, terephthalic acid, maleic acid, octadecenyl maleic acid, fumaric acid, trimellitic acid, adipic acid, malonic acid, glutaric acid and phthalic anhydride, phthaloyl chloride and phthalic acid. There are corresponding acid anhydrides, acidifieds and acid esters such as dimethyl ester. Preferred polycarboxylic acids are aliphatic and alicyclic dicarboxylic acids having 14 or less carbon atoms and aromatic dicarboxylic acids having 14 or less carbon atoms.

The curable composition may be unsaturated polyester-based, many of which are obtained from the same monomers as the polyol esters described above. The unsaturated polyester exists as a diluent such as styrene in combination with an unsaturated monomer. Unsaturated polyester resins are usually the reaction products of one or more unsaturated dibasic acids and one or more dihydric alcohols described in the previous paragraph. Curing or polymerization of unsaturated polyesters requires initiators and accelerators, but once free radical polymerization is initiated, the polymerization will continue. Suitable accelerators are substances such as diethylaniline, dimethylaniline and N, N-dimethyltoluidine. Suitable initiators are benzoyl peroxide, ethylmethylketone peroxide, cumene hydroperoxide and dichlorobenzoyl peroxide. Of course, other accelerators and initiators for unsaturated polyesters may be used, which are well known to those of skill in the art.

Another type of curable polymeric resin for which the present invention can be used is polyurethane prepolymer resins. The polyurethane prepolymer resin contains a free isocyanate moiety or group as a reactive or polymerized moiety of the molecule and is typically a reaction product of a poly (alkylene) glycol with a polyisocyanate. Specifically, the polyurethane prepolymer is a reaction product of poly (1,4-butylene oxide) glycol and tolylene diisocyanate and / or methylene diisocyanate. The resin has 5 weight percent free isocyanate groups available for the reaction. Suitable curing agents for use with this polyurethane prepolymer resin may be methylene-bis- (o-chloroaniline), polyol (1,4-butanediol) or trimethylolpropane or even water. Other suitable polyurethane resins include those that have free hydroxyl or olefin functionality and are cured via free radical polymerization. Suitable catalysts for this polyurethane prepolymer resin are tin carboxylate, organosilicone titinates, alkyl titinates, biscarboxylate, tertiary amines, amidines, tin mercaptides, lead, cobalt, manganes, bismuth or iron. Such as naphthenate or alkanoate salt. Specifically, tin (II) diacetate, tin (II) dioctanoate, tin (II) dilaurate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, tin octylate, tin oleate, tin acetate, Tin laurate, 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine, triethylamine, tributylamine, dimethylbenzylamine, N, N, N', N'tetramethylethylenediamine, 1,2-dimethylimidazole, Triethylenediamine, tetrabutyl titanate, tetrapropyl titanate and the like.

The adhesive to which the present invention is applied may be a liquid polysulfide prepolymer system containing an oligomer polysulfide having a thiol group as a terminal group. The polysulfide has a chemical structure represented by HS (R-Sx) nH, where x is a small number from 1 or 2 to 4, n is an integer from 1 to 25, and R is. It is alkylene, arylene or alkoxyalkylene, especially -CH2CH2- and / or -CH2 (OCH2CH2) 2-, and often further contains a branching group -CH2CHCH2-. Preferred oligomeric polysulfides are polyalkylene sulfides such as polyethylene sulfide and polypropylene sulfide and poly (2,4-trilensulfide), poly (4,4'-biphenylene sulfide) and poly (phenylene sulfide) (PPS) and the like. It is of the polyarylene sulfide system of. Oligomer polysulfide having a thiol group at the end is polymerized or cured by reacting with an epoxy or phenol resin or compound or diisocyanate. Preferred polysulfide-based adhesives can be formed by reacting polysulfide having a thiol group at the end with a bifunctional or polyfunctional epoxide such as diglycidyl ether of bisphenol A. Alternatively, the polymerization may be carried out by reacting the terminal thiol group with an olefin, for example, by reacting with polyethylene glycol dimethacrylate. Curing agents for curable polysulfide include manganese dioxide, lead dioxide, antimony trioxide and tellurium dioxide.

Furthermore, the present invention can also be used for silicone-based adhesives and sealant compositions. They have a silicon-containing group, which has a hydroxyl group or a hydroxyl group attached to a silicon atom and a hydrolyzably unstable group, which is crosslinked by the formation of a siloxane bond. Preferred curing agents are tin octylate, lead octylate and dibutyltin dilaurate. These curable compositions are particularly useful as sealing compositions in which weather resistance and weather resistance are important.

As mentioned above, the curable composition is a monomer of the same general chemical type or a different chemical type, as long as the system is compatible and the resulting cured or polymerized adhesive or sealant has the intended characteristics. , Oligomers and / or a mixture of prepolymers. When using a combination or mixture of monomers, oligomers and / or prepolymers, there are three mechanisms by which the secondary component is incorporated by or within the composition of the primary curable component. In the first mechanism, the second polymerizable component has a plurality of reactive or functional sites for co-reacting or copolymerizing with the first component. In the second mechanism, the second component has polar groups such as oxygen, amines, ethers, hydroxyls, ketones, epoxies or carboxyls that form hydrogen bonds with the cured or polymerized primary components. In the third mechanism, the second component is like sterically entangled or hindering the movement of the opposing chains of the primary component.

3-butylene glycol di (meth) clearate, tripropylene glycol di (meth) clearate, ethoxylated bisphenol di (meth) clearate, dipropylene glycol di (meth) clearate, alkoxylated hexanediol di (meth) clearate, alkoxylated cyclohexane Dimethanol di (meth) glycolate, pentaelthritol tri (meth) glycolate, and mixtures thereof. As a matter of course, those mentioned above for various polymerizable components are also included as other preferable materials. To exemplify the second component having a polar group for forming a hydrogen bond, alkoxy acrylate, alkoxy methacrylate, polyester acrylate, polyester methacrylate, acrylic alkoxyphthalic acid, methacrylic alkoxyphthalic acid, glycidyl methacrylate, glycidyl acrylate, cycloalkoxy acrylate, Cycloalkoxymethacrylate and the like. Suitable second components that are sterically entangled with or hinder the movement of the opposing chains of the adhesive polymer that is finally formed are alkyl (meth) clearates with more than 14 carbon atoms, cycloalkyl (meth) clearates. , Polycyclic alkyl (meth) clearate, aralkyl (meth) clearate, cycloalkoxy (meth) clearate. Specific examples include stearyl acrylate, stearyl methacrylate, isobornyl methacrylate, benzyl acrylate, cyclohexyl methacrylate and cetyl acrylate.

Optionally, the curable composition may further comprise a terpene resin such as a wood rosin resin, an ester of rubber rosin, a styrene terpene, a terpene phenol resin. These terpene resins function as thickeners. The adhesive strength of the curable composition on an oiled metal sheet is from 1 to 10 weight percent of the weight of the curable composition with a fat-soluble additive such as limonene, dipentene, terpene resin or turpentine. It can be enhanced by inclusion. Other optional ingredients include dyes, stabilizers, inhibitors, thickeners and the like.

The above is a description of the outline of the innumerable curable compositions to which the present invention is applied, and the present invention is limited to the above-mentioned curable compositions or the specific polymerizable components described therein. It's not something. And, of course, these compositions may optionally contain other additives well known to those of skill in the art, such as dyes, pigments, plasticizers, stabilizers, solvents, surfactants, emulsifiers and the like. Another curable composition that can be modified according to the teachings of the invention to provide the advantages and properties of the invention is self-explanatory and readily recognized by those skilled in the art. Such curable compositions are Mahdi et. Al. (US Pat. No. 20020,010,272), Bachmann et. Al. (US Pat. No. 3,814,156), Chermack (US Pat. , Wallace (US Pat. Nos. 4,428,982 and 4,081,012), Krieble (US Pat. Nos. 3,489,599 and 3,746,068), Newell (US Pat. No. 4,252,708), Cropp et. al. (US Pat. No. 6,573,328), Matsuo (US Pat. No. 6,025,074), Fryd et. Al. (US Pat. No. 4,980,410), Azevedo (US Pat. No. 4,417,028), Cooke et. Al. 4,497,916), Chao (US Pat. No. 6,375,872), Usami et. Al. (US Pat. No. 5,397,812), Wolinski et. Al. (US Pat. No. 4,126,504), Siebelt et. Al. (US Pat. No. 5,140,068). And 5,157,077), Deckert et. Al. (US Pat. No. 3,746,068), Hart et. Al. (US Pat. No. 4,536,524), Earls et. Al. (US Pat. No. 5,510,431), Hilbelink et. Al. (US Pat. No. 3,725,501), Sweeney (US Pat. Nos. 4,830,558 and 4,555,206) and Rich et. It is disclosed in al. (US Pat. Nos. 5,635,546 and 5,853,520), the contents of which are incorporated herein by reference.

The method for preparing the curable composition of the present invention depends on the usage pattern and method of the composition. In the case of liquid or thickened adhesive and sealant compositions, the encapsulated carrier particles are simply blended into the liquid curable composition by any known method and commercially employed technique. Preferably the composition is thickened naturally or by the addition of a suitable thickener and / or thixotropy such as fumed silica so that the encapsulated carrier particles do not settle during storage. The curable composition is also stirred before use.

The curable composition is used pre-applied, i.e. applied to an adherend that is stocked and stored before use, eg, applied to a nut or bolt at a factory or processing site for use elsewhere. When attached, the encapsulated carrier particles are dispersed in a liquid-curable component applied to the adherend, applied to the adherend, on which a polymer film of the liquid-curable composition is formed. The liquid-curable component formed, or preferably the liquid-curable component, is also encapsulated, and the encapsulated liquid-curable component and the encapsulated carrier particles are dispersed in a suitable binder for adhering the capsule to the adherend. .. In the case of the first example, after the liquid curable composition of the present invention is applied to the adherend, a thin film of the liquid polymerizable material or a solution of the film forming material is applied, and the liquid curable composition under the thin film is applied. Covers, thereby wrapping or covering the liquid curable composition between the film and the adherend. It is also possible to obtain such a protective film from the curable composition itself. In this case, the curable composition comprises a suitable photoinitiator and / or photosensitizer, and proper irradiation, preferably UV light, initiates curing of the surface of the liquid curable component. Such curable compositions may include suitable UV screening agents, which ensure that only thin surface films cure or polymerize. Such systems are taught in Ozono (US Pat. No. 4,588,639) and Wallace (US Pat. No. 4,428,982) and are readily available, which are incorporated herein by reference. Well known to those skilled in the art.

Usually and preferably, the liquid curable composition and curative are encapsulated and the microcapsules are dispersed in a suitable binder. The binder is selected according to the composition of the wall material and the composition of the adherend. The binder system may be a curable binder system using the same or similar curable or polymerizable materials as those useful for forming shell walls and / or adhesives or sealants. Suitable curable binder systems are by reaction of anhydride with arylene, alkylene, alkoxylene, alkalilene, aralkylene, alkoxyalkylene, aryloxyalkylene and aryloxy arylene. Suitable binders are water-soluble binders such as polyvinyl alcohol, styrene-maleic anhydride copolymer, gelatin and chloroprene, polyester acrylate, urethane acrylate, carboxy or hydroxy-modified vinyl chloride-vinyl acetate copolymer, cellulose acetate, Epoxide, polyterpene, hydroxypropyl cellulose, hydroxyethyl cellulose, sodium carboxymethyl cellulose, poly (glycolic acid), poly (lactic acid), copolymers of these, poly (aliphatic carboxylic acid), polycaprolactone, poly (acetal), poly ( Lactic acid-caprolactone), poly (glycolic acid-caprolactone), polyan anhydride, albumin, casein, butyrate resin, polyvinyl acetate, polyester with dibasic acid and diol, polyvinyl chloride, polyvinyl butyral, polyvinyl formal, varnish and tar resin And wax. Suitable organic solvents for these binders are chlorine-based solvents such as trichlorethylene, trichloroethane, methylene chloride; chlorine / fluorine-based hydrocarbons such as monofluorotrichloroethane and dichlorodifluoroethylene; hydrocarbon solvents such as hexane and pentane, ethanol and isopropanol. Etc. alcohol; And lacquer solvents such as methyl ethyl ketone, toluene and benzene. Other binder systems are disclosed, for example, in Park et. Al. (US Pat. No. 5,827,924), Matsuo (US Pat. No. 6,025,074) and Bachman et. Al. (US Pat. No. 3,814,156). Are cited herein, and these are well known to those of skill in the art.

Particularly desirable binder systems are those that are photopolymerizable, i.e. those that cure or polymerize when exposed to light, preferably ultraviolet light. The binder system comprises the curable monomers, oligomers and / or prepolymers described above and suitable photoinitiators and / or photosensitizers. Suitable photoinitiators are benzoin and its derivatives, benzophenone and its derivatives, xantone, benzyl, benzylketal (particularly benzylmethylketal), acetophenone and its derivatives (particularly α, α-diethoxyacetophenone), α-hydroxyalkylphenone. , O-acyl-α-aminoketone, acylphosphine oxides (particularly 2,4,6-trimethylolbenzoyldiphenylphosphine oxides) and acylphosphonates. Other initiators include substituted pyrylium salts, derivatives such as anthracene and substituted anthracene, anthraquinone or ketocoumarin derivatives, and the like. Generally, the photoinitiator is used in an amount in the range of about 0.5 to 10 percent by weight of the binder composition, preferably about 2 to 4 percent or more by weight of the total binder composition. Separately or additionally, the photopolymerizable binder may include a photosensitizer. Suitable photosensitizers are dyes such as benzophenone or eosin, fluorescein, thiazole dyes, thiazine dyes, oxazine dyes, azine dyes, aminoketone dyes, xanthan dyes, acridinium dyes or phenazine dyes. By adding such a photosensitizer, the exposure intensity of the irradiation used to initiate curing can be reduced and / or the exposure time can be shortened. In the case of photoinitiated polymerization, generally photoinitiated radical generating components such as peroxides, peracid esters, azo compounds and derivatives, benzoin derivatives, alpha-haloacetphenone or acylphosphine oxides are added to the total binder composition weight. About 0.005 to 4% or more (preferably about 0.01 to 1. It is desirable to use in amounts in the range of 5 percent). Although the above description mainly relates to free radical photopolymerization, suitable binder systems are similarly photoionically activated. Suitable cationic light generators are iodonium salts, especially diallyl iodonium salts. Such iodonium salts are described in US Pat. Nos. 3,729,313, 3,741,769, 3,808,006, 4,250,053 and 4,394,403. The iodonium salt may be a monosalt containing anions such as chloride, bromide, iodine, antimony pentafluoride or scénic hexafluoride. If desired, a mixture of iodonium salts can be used. Iodonium cation photoinitiators are commonly used in combination with sensitizers and electron donating compounds. Therefore, a particular iodonium salt is determined to some extent depending on the particular polymerizable component, sensitizer and donor.

The binder composition may contain other ingredients such as curatives and additives for adhesives and sealant compositions. However, when a curative is included, the curative is such that even if the microcapsules containing the curable component of the curable composition are destroyed at an early stage, the component is not cured or polymerized at an early stage. Thus, for example, the accelerator may be dispersed in the binder as long as the initiator of the given curable composition is in the encapsulated carrier or another encapsulated component of the curable composition.

The amount of encapsulated curable system incorporated into or used with the curable composition is the type of curable composition, i.e. it is an addition-polymerizable system or a step-growth polymerizable system. The state of the curable composition, that is, whether it is a liquid system or a fully encapsulated system in a binder, the desired degree of curing or polymerization, the amount of curable component and / or stoichiometry, It depends on many different parameters such as the amount of curative in the carrier particles. Those skilled in the art should be able to easily recognize and determine the suitable content. In many cases, the amount of encapsulated curing system containing the same amount of curative as in the absence of carriers may be adopted.

In the case of pre-applied adhesives and sealant compositions, the amount of encapsulated curing system incorporated into the binder system is also affected by the method and amount of application of the composition and the composition of the binder. The binder composition containing the binder polymer in the solution state contains a smaller amount of encapsulated components (both curable and curable components) than the liquid curable binder system on the basis of the total weight of the binder system. It is usually preferred to minimize the amount of binder material and at the same time maximize the amount of encapsulated components (both curable and curable components) for optimal adhesion or sealing performance. The amount of encapsulated curing system generally combined with other microencapsulated components is consistent with the amount used in conventional encapsulated adhesive and sealant compositions. However, smaller amounts can also be employed by efficiently mixing the curative and curable composition during activity.

The curatives in the encapsulated curing system of the present invention are released by high shear, especially by high shear mixing to knead or knead the carriers, or, in the case of heat-flowing carriers, by moderate shear mixing, and / Or become available. The specific way to do this is whether the carrier, the encapsulated curing system is part of a liquid adhesive or sealant composition, or a pre-applied adhesive or sealant composition, and the latter. In this case, it depends on the properties of the adherend to which the pre-applied composition is applied. For example, in the case of a liquid curable composition containing an encapsulated curable system, the curable composition is cured by discharging or applying through a high shear mixing element or an element similar to a screw in an extrusion barrel. You may go. Separately, a bead of a liquid-curable composition containing an encapsulated carrier may be overlaid on the adherend and mixed or kneaded with a mixer blade or a series of mixer blades. The mixer blade may be in the form of multiple stationary dams, and as the adherend passes through these dams with the beads, the dams move the beads and knead to expose the curative, curative and curable composition. Homogeneously mix with the ingredients of.

If the carrier in the liquid curable composition is a hot melt wax material or a heat sensitive material, the nozzle has a heating element combined with a mixer element, which may be a high shear mixer element. , Not required, which causes the carrier to be softened or transformed into a fluid state by the heat generated by the heating element. Separately, following the last sentence of the previous paragraph, the blades and / or dams may be heated to make the thermal material flexible and / or fluid at the same time as mixing with the curable composition.

In the case of pre-applied adhesives or sealant compositions, the curing or polymerization of the curable composition is carried out by a mixer blade that repeatedly passes through the pre-applied curable. In a high speed industrial production process, the adhesive passes through a stationary or reciprocating blade or mixer element, which may or may not be heated. In the case of a stationary element, the element itself may have a series of dam-like structures, which are plow-like pre-applied curable compositions as the pre-applied composition is scraped from the surface of the adherend. Plays the role of pressing and mixing. In any case, the adhesive mixture has a high viscosity due to the presence of carrier components and / or thickening or viscosity-enhancing additives, so that the curable composition that begins to cure through the mixer portion will have a raised ridge. When the curable composition, which has become shaped and has begun to cure, is brought into contact with the two adherends, the composition comes into contact with both surfaces of the adherends, especially between the surfaces of the adherends which are not flat. Fill the gap.

What is important in the mixer element is to knead or knead the curable composition to ensure that it breaks the shell wall, and more importantly, to grind or knead the carrier repeatedly and more. It is to expose the curative that was taken.

Due to the high viscosity of the activated adhesive and sealant composition as described above, the activated material resulting from the activation step when the composition is activated according to the means by which it is activated or when activated. It can be applied as a raised bead or multiple beads. This feature allows a thin film of pre-applied adhesive to be applied to a given stock material that will be stored until next use. Since the adhesive is applied as a thin layer, there is no concern that the adhesive will tilt or collapse even if the processed materials are stacked high. Some processed materials may already have a thin film of the reactive adhesive material coated on their surface, and the thickness of the adhesive layer is limited to the thickness of the pre-applied reactive adhesive material. However, in the present invention, the physical and fluid properties of the activated adhesive and sealant composition can create raised beads that can fill uneven surfaces and gaps. These are applications that cannot be addressed by conventional pre-applied membranes.

The following examples illustrate further scope of the invention and facilitate understanding of the invention, but do not limit the invention.

Encapsulated curing system Some of the novel encapsulated curing systems according to the invention (hereinafter referred to as "ECS") are the internal phase of the ECS microcapsules, i.e. the carrier material or its precursor if the carrier is in-situ polymerized, and It was made in a multi-step process consisting of the preparation of the curative contained in the carrier and one or more wall forming or encapsulation steps. Generally, the internal phase is prepared by adding a plasticizer, a polymer thickener and / or a tackifier resin to the polymerizable monomer in a suitable container or beaker, and stirring at room temperature until all the solids are dissolved in the monomer. .. The heat-sensitive components incorporated into the carrier, such as peroxides and azo initiators, are then added to the mixture, at high temperatures, usually 45 ° C., until all solids are completely or substantially completely dissolved. Stirred or mixed constantly with. The first mixing step was carried out at room temperature because the resin did not dissolve in the monomer depending on the temperature and took time. On the other hand, the curative mixing is more temperature dependent and is preferably carried out at a high temperature. Of course, it should be possible to add all the ingredients in different orders at high temperatures, but due to the slow rate at which the resin dissolves in the monomers, long-term high temperature mixing can be effective or effective for the curative. It has an adverse effect.

Encapsulation of the internal phase of ECS was performed in one, two or three-step multi-step steps, preferably two-step steps. Unless otherwise indicated, all encapsulation steps were performed in a jacketed steel vessel or reactor under a nitrogen blanket with integrated stirring means to ensure good mixing of the ingredients therein. .. The two-step encapsulation step consists of the following general steps. -A homogeneous mixture of colloidal polyacrylic acid (C-121 ...), sodium hydroxide (5% solution) and water was prepared in a reaction vessel. -Then, a partially methylated methylolmelamine resin solution (Cymel 385) was added to the above mixture under constant stirring. Due to the high viscosity of this material, its addition was carried out over 4 minutes. -After the addition of the melamine resin was completed, the ECS internal phase material was added to the mixture under constant stirring. -Usually after about 16 minutes, the ECS internal phase material is homogeneously mixed and the reaction mixture is subjected to high shear treatment at room temperature or preferably slightly higher temperature to obtain the desired particle size of the ECS internal phase material. High shear or emulsification conditions were obtained by an integrated or inserted impeller device. Particle size measurements were performed regularly to determine the progress of emulsification. -Just before the completion of the emulsification step, usually 5 minutes before completion, the wall-forming composition of the second stage encapsulation step was prepared. As described above, the second stage wall forming composition was prepared by adding a partially methylated methylolmelamine resin to a mixture of colloidal polyacrylic acid, sodium hydroxide and water. -Five minutes after the interruption of the emulsification step, the prepared second step wall forming composition was added to the mixture, with it maintained under constant agitation. -After the addition of the wall forming composition of the second step, a salt, preferably sodium sulfate, is added to the mixture to complete the encapsulation step. -The temperature of this reaction mixture is then gradually increased within about 2 hours, preferably within about 1 hour, and the temperature is maintained for a long period of time to ensure capsule wall formation and ECS internal phase polymerization. Complete.

It is clear that the above procedure is one of many applicable in carrying out the present invention, and one of ordinary skill in the art should readily recognize that many modifications and variations can be successful. Is. For example, the wall forming material and the ECS internal phase material can be added at the same time or in the reverse order. However, since the wall forming material is considered to assist the emulsification step of the internal phase material, the above specific order is desirable. In addition, the time of the encapsulation process depends on many factors such as the type, size and shape of the impeller blade and the speed. High shear provides smaller particle sizes, but those skilled in the art should understand that continued high shear mixing does not cause further particle size changes in the material over a period of time. Is. Particle size measurements were performed using an Accusizer Model 780 size instrument manufactured by Particle Sizing Systems during or after the encapsulation process.

[Example 1-19] Several different microencapsulated novel active systems were prepared according to the present invention. In each of these examples, carriers were in-situ polymerized simultaneously or after encapsulation. The formulation of the internal phase of ECS microcapsules is shown in Table 2, and the amount shown therein is in grams. In addition to those shown below, ECS microcapsules were prepared according to the above two-step encapsulation step using the cell-forming materials shown in Table 3 under the reaction conditions and times shown in Table 4. Table 4 also shows the physical properties of the formed microcapsules: average particle size and cell wall content.

<tables num="1-a"><img id="000002" he="220" wi="159" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables> Table 1-a and Table 1-b are one table.

<tables num="1-b"><img id="000003" he="180" wi="159" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="2"><img id="000004" he="234" wi="159" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="3"><img id="000005" he="244" wi="136" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="4"><img id="000006" he="245" wi="129" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

In Example 3, unlike this series of other examples, a two-step heating cycle was adopted to bring the final reaction mixture to the final reaction temperature. Specifically, as shown in Table 4, the reaction mixture is first heated to 45 ° C and maintained at that temperature for 10 minutes, then heated to 80 ° C and maintained at that temperature overnight. The phase material was polymerized.

In Example 8, the ECS internal phase is added to the wall-forming premixture of polyacrylate, sodium hydroxide and water, emulsified for 45 minutes, wall-forming melamine resin is added and the mixture is emulsified for an additional 30 minutes. It was.

Finally, in Example 18, two-step carrier polymerization was employed, the first polymerization was carried out at 65 ° C for 6 hours as shown in Table 4, then the temperature was raised to 80 ° C and the reaction was continued for an additional 6 hours. ..

[Example 20-22] The second example group was prepared using the two-step encapsulation step again without adding the polymerizable wall-forming material during the second step. The second step of the encapsulation process is simply the addition of a solution of sodium hydroxide, sodium sulfonate and water, as evidenced by Table 5, which shows the composition of the ECS internal phase and the composition of the wall-forming material. The reaction conditions and the physical properties of the formed microcapsules are shown in Table 6. As can be seen from Table 6, in Example 22, the above-mentioned implementation was carried out except that the first polymerization step was carried out at 65 ° C for 6 hours, the reaction temperature was raised to 90 ° C in the second step, and the reaction temperature was maintained for 16 hours. Two-step carrier polymerization was adopted as in Example 18.

<tables num="5"><img id="000007" he="191" wi="144" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="6"><img id="000008" he="108" wi="147" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

[Example 23-25] Examples 23 and 24 and 25 exemplify another encapsulation step in which the encapsulation is encapsulated in a single step or a three step step. The composition, production method and characteristics of the obtained ECS microcapsules are shown in Tables 5 and 6.

Adhesive composition In order to prove the effect and usefulness of the encapsulated curing system of the present invention, several formulations of curing adhesives incorporating some of the above encapsulated curing systems were prepared. In Example 26, ECS microcapsules were used for the one-component liquid adhesive composition, and in the remaining examples, all ECS microcapsules and encapsulated curable compositions (hereinafter referred to as "ECC") were used. Combined in a binder system, it was applied to various adherends, dried, or cured and activated as needed.

Table 7 shows the internal phase of various microcapsules, including the curable composition, and the composition of the wall forming material used in encapsulating the curable composition. Generally, the method of forming ECC microcapsules is as follows. -Mix the components of the ECC internal phase under a nitrogen blanket until all of these are dissolved and hold until the next use. -All components of cell wall phase I except melamine resin are added to a steel reactor maintained at 25 ° C and mixed at low shear, i.e. 300 rpm, melamine resin is added and mixed at low shear for an additional 4 minutes. did. -The prepared ECC internal phase formulation was added to the reactor and homogeneously mixed at 300 rpm for an additional 16 minutes. -The mixture was highly shear emulsified at 3000 rpm for 75 minutes at 25 ° C. During this time, the second stage wall forming material was prepared by adding melamine to the remaining components of the second stage wall composition approximately 5 minutes before the completion of the reaction mixture emulsification step. -After the emulsification was complete, the mixture in the reactor was continuously mixed with a flat paddle mixer at low shear, ie 300 rpm. Approximately 5 minutes after discontinuing the emulsification step, the second wall forming composition was added to the mixture and at this stage if sodium sulphate was used. -The reactor temperature was then gradually increased over about 2 hours and the reaction mixture maintained at 65 ° C was low shear mixed for an additional 8 hours before collecting the ECC microcapsules.

Some of these pre-applied microencapsulated adhesive compositions used aqueous base binders and some used UV curable binders. The compositions of the various UV binders used in the examples below are shown in Table 8. These binders were adjusted under ambient conditions using a conventional mixer, being careful not to expose them to UV light.

[Example 26] 6.7 parts by weight of tetramethylanaline, 33.3 parts by weight of the encapsulated curing system prepared in Example 19 and 60 parts by weight of dipentaerythritol pentaacrylate (Sartomer SR399) are mixed to form a one-component liquid. A curable adhesive composition was prepared. A thin film of this liquid adhesive composition was applied to an aluminum plate (0.75 "x 4") on which another aluminum plate was placed. These plates were moved 1 inch with finger pressure and rubbed about 10 to 20 times. The plates were then left for 5-10 seconds to confirm that the plates could not be pulled apart, which means that the adhesive had hardened.

[Example 27] 4 parts by weight aqueous solution containing 5% by weight polyvinyl alcohol and 5% by weight benzoyl peroxide, 2 parts by weight p-toluenesulfonic acid (p-TSA), 20 parts by weight ECC microcapsules A, 74 parts by weight of the encapsulated curing system prepared in Example 1 was mixed to prepare an aqueous pre-applied adhesive composition. One chipboard was pretreated with a # 16 rod with a coating of 5% polyvinyl solution. The treated surface was further coated with the adhesive using a # 50 rod. The coating was dried and the edge of the blade was manually moved over the pre-applied adhesive about 10 times under hand pressure using a razor blade. The chipboard was then bent and held by hand pressure for 10 seconds. The chipboard remained glued after the release.

[Example 28] Prepared with 15 parts by weight of styrene acrylic latex emulsion (Jonacryl 3050), 3.5 parts by weight of sodium bicarbonate, 0.4 parts by weight of polyacrylate (TT-615-Rohm &amp; Hass), and 52 parts by weight of Example 6. A second aqueous pre-applied adhesive composition was prepared by mixing 14.2 parts by weight of ECC microcapsules B and 14.2 parts by weight of ECC microcapsules C with the encapsulated curing system. This composition was applied to the news back stock as a thin film (0.006 inch) on the clay-coated side. The thin film was dried and the edge of the blade was manually moved over the pre-applied adhesive about 10 times under hand pressure using a razor blade. The news backstock was bent under pressure with fingers and closed like a flap on a cereal box. The news backstock remained glued after the pressure was released, and when pulled apart after 1 minute, a strong bond was felt. Fiber tearing was observed when the flaps cured for 5 minutes and 1 hour were pulled apart.

[Example 29-36] A series of pre-applied adhesive compositions in UV curable binders were evaluated using the encapsulated curable system of the present invention. The composition of these pre-applied curing systems is shown in Table 9, the composition of the encapsulated curing system composition (ECC) is shown in Table 7, the composition of the binder system is shown in Table 8, and the encapsulated curing system (ECC). ECS) is specified by the number of Example, eg ECSCap5 means the encapsulated curing system prepared in Example 5.

<tables num="7"><img id="000009" he="184" wi="159" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="8"><img id="000010" he="124" wi="146" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="9"><img id="000011" he="112" wi="159" file="JP5366291B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

In each of these examples, the adhesive composition was applied as a thin film 0.5 inches wide and 0.006 inches thick along the centerline of the spindle of a 3 inch wide, 5 inch long card cut from the paperboard of the cereal box. .. The adhesive film was applied to the fiber side of the card and cured with UV light. The adhesive was activated and the card was glued to a similar card using a specially designed activator. The device consists of an insertion station, an activator station, an adhesion station, and a thread traveling along this rail, which has a rail terminated at the adhesion station from the insertion station via the activator station. When testing the prepared sample, place the adhesive pre-applied card on a vacuumed thread with the adhesive side up and its spindle parallel to the rail spindle. did. Threads are passed along the rails at a rate of 150 to 250 feet per minute through the activation station, where the glue is lifted from the card and rubbed on the surface with one or more ridges, dams or other structures. The static activating means has crush the microcapsules, mix their contents and re-deposit the adhesive on the curd. The thread then passes through a bonding station where the activated card is combined with another card at a pressure of about 5 psi for about 12 seconds. After that, the adhered card was left for 4 weeks, and the final peeling adhesive strength and shear adhesive strength were measured. Each adhesive system was tested with 5 card adhesives, and the average of the results was taken and shown in Table 9.

Peeling and shearing adhesiveness tests were performed using a Thing-Albert EJA materials tensile tester with a 200 lb weighted cell under Tappi conditions. During the test, the device settings were test speed: 12 inches per minute, sensitivity: 0.5 lbs and gauge length: 1.75 inches. Each sample is placed in a vice-grip clamp that extends over the length of each sample and is located parallel to and below the area of the bond, thereby stabilizing the area of adhesion prior to testing. did. The clamp was strained to tighten the bond line without applying pressure. The clamped assembly was bent to prepare for the following specific tests.

Peeling Test: The exposed, non-glued flap of the glued card extending from the clamp was bent 90o against the card in the opposite direction along the edge of the clamp to perform the peeling test. Cards folded in this way have a T-shape. The bent card was held by the opposing jaws on each flap and placed in the center of the tensile tester. This completes the test preparation.

Shear Adhesiveness Test: To perform this shear test, the exposed and unbonded flap corners of the glued card were bent 90o against the glued card. At the opposite end of the other card of the glued card, the corner was similarly bent 90o in the direction opposite to the first bent corner. Each jaw of the tensile tester was attached to one of the bent corners. This completes the test preparation.

[Example 37] Finally, a pre-applied composition was prepared and the effectiveness of the composition of the present invention in screw locking applications was demonstrated. In this example, 23 parts by weight of UV binder R shown in Table 8, 20 parts by weight of ECC microcapsules K from Table 7 and 57 parts by weight of the encapsulated curing system of Example 19 were used. The composition was prepared.

To test the efficacy of these compositions, a band of 0.5 inch wide adhesive was applied to the threads of multiple bolts 1/2 inch long and 1/4 inch in diameter. This band was cured under UV light. The nut was manually screwed into the bolt until it reached the upper edge of the adhesive band. I left them for a few hours and then tried to remove the nuts by hand, but I couldn't. Although the actual adhesive strength was not measured, the adhesive cured and formed an effective adhesive surface.

Although the present invention has been described with respect to the particular embodiments and examples described above, other embodiments using the concepts of the invention are possible without departing from the scope of the invention. The present invention is defined by all modifications, modifications or equals relating to the elements described in the claims and the scope of the principles contained or embodied therein.