Production of aqueous emulsion of rosin substance, its aqueous emulsion composition and sizing agent

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention is a method for producing an aqueous emulsion of a rosin-based substance having excellent storage stability and mechanical stability, which cannot be obtained by a conventional method, by using a high-shear rotary emulsifier, and an aqueous solution of the rosin-based substance. The present invention relates to an emulsion composition and a papermaking sizing agent that exhibits excellent sizing performance using the emulsion composition.

【0002】

[Conventional technology]

Aqueous emulsions are used in many industrial fields because they can supply water-insoluble hydrophobic substances as aqueous liquids with low viscosity and high concentration. In particular, aqueous emulsions using rosin-based substances as hydrophobic substances are used. It is used as a sizing agent for papermaking and a modifier for paints and inks. Known methods for producing an aqueous emulsion of a rosin-based substance include a high-pressure discharge emulsification method using a solvent, a high-temperature high-pressure discharge emulsification method using no solvent, and a phase inversion emulsification method. The high-pressure discharge emulsification method (solvent method) using the above solvent is a solution in which a rosin-based substance is dissolved in a water-insoluble volatile organic solvent such as toluene, as described in Japanese Patent Publication No. 54-36242. After the state, it is premixed with an emulsifying dispersant and water to prepare a coarse-grained aqueous emulsion, and the mixed solution is emulsified with a high-pressure discharge emulsifier such as a homogenizer to form an emulsion of fine particles, and then further. This is a method for obtaining an aqueous emulsion by distilling off an organic solvent. This method has an advantage that it is not necessary to raise the temperature during emulsification because the rosin-based substance is in a solution state even at room temperature. Also, the above In the high-temperature and high-pressure discharge emulsification method (high-temperature and high-pressure method) that does not use a solvent, as described in Japanese Patent Application Laid-Open No. 50-156564, the rosin-based substance is heated above the softening point to be in a molten state. , An emulsion dispersant and water are premixed to prepare a coarse-grained aqueous emulsion, and the mixed solution is emulsified with a high-pressure discharge emulsifier to obtain an aqueous emulsion of fine particles. Further, in the phase inversion emulsification method, as described in Japanese Patent Application Laid-Open No. 52-77206, water in oil is added while adding an appropriate emulsification dispersant and water to the heat-melted rosin-based substance under stirring. This is a method of obtaining an aqueous emulsion by inverting the phase from a mold emulsion to an oil-in-water emulsion.

【0003】

[Problems to be Solved by the Invention]

However, the above-mentioned solvent method has low productivity because a solvent removal step is required after the completion of emulsification, and further, the use of an organic solvent has an adverse effect on the environment and occupational safety and health in performing operations such as manufacturing. There's a problem. Further, in the above-mentioned high-temperature and high-pressure method, in order to reduce the melt viscosity of the rosin-based substance, the rosin-based substance is heated to a high temperature of, for example, 180 ° C, and further, 560 Kg / cm.²It is necessary to emulsify under high pressure, such as the seal material of the high pressure discharge type emulsifier is severely deteriorated, continuous operation for a long time is difficult, not only the process is inferior in productivity, but also rosin-based substances in particular. When the softening point becomes high, there is a problem that it is difficult to obtain a uniformly finely divided emulsion. As an improvement method, in Japanese Patent Application Laid-Open No. 8-117578, a high shear type rotary emulsifier (CAVITRON) is used instead of the high-pressure discharge type emulsifier, and in Japanese Patent Application Laid-Open No. 7-155576. A method using a high-pressure collision type emulsifier (microfluidizer) instead of the high-pressure discharge type emulsifier has been proposed. However, in any method after the improvement as well as before the improvement, if the softening point of the rosin-based substance is high, it is necessary to raise the temperature at the time of emulsification and dissolve it at a higher rotation speed or a higher pressure. Not only is it difficult to obtain an emulsion of fine and uniform particles, but there is also a problem with the durability of the emulsifier, which makes stable continuous production difficult, and emulsification that deteriorates due to the melting temperature of rosin-based substances. There is a problem that the dispersant cannot be used. Further, while the above method does not require a large shearing force in the phase inversion emulsification method, it is necessary to use a large amount of emulsification dispersant in order to obtain a fine and stable aqueous emulsion. There is a problem that foamability becomes a problem when a product is used using an emulsion, and that an emulsion dispersant that can be used in a phase inversion emulsification method that deteriorates at the melting temperature of a rosin-based substance cannot be used.

【0004】

The first object of the present invention is a method for producing an aqueous emulsion of a rosin-based substance, which does not have an adverse effect on the environment or a problem in occupational safety and health as in the solvent method, and an aqueous emulsion of the rosin-based substance. The purpose is to provide a composition and a sizing agent. A second object of the present invention is that it is difficult to obtain an emulsion of fine and uniform particles when a rosin-based substance having a particularly high softening point is used as in the high-temperature and high-pressure method, and there is a problem in the durability of the emulsifier. It is an object of the present invention to provide a method for producing an aqueous emulsion of a rosin-based substance, an aqueous emulsion composition of the rosin-based substance, and a sizing agent so as not to interfere with continuous production. A third object of the present invention is a method for producing an aqueous emulsion of a rosin-based substance obtained without using a large amount of emulsifying dispersant as in a phase inversion emulsification method, an aqueous emulsion composition of the rosin-based substance, and a sizing agent. To provide. A fourth object of the present invention is to provide an aqueous emulsion of a rosin-based substance that does not prevent the use of an emulsion dispersant that deteriorates at high temperatures due to high-temperature treatment as in the high-temperature and high-pressure method and the phase inversion emulsification method. It is an object of the present invention to provide an aqueous emulsion composition of a production method, a rosin-based substance thereof, and a sizing agent. A fifth object of the present invention is a method for producing an aqueous emulsion of a rosin-based substance, which can be emulsified by a combination of a rosin-based substance and an emulsion dispersant, which has been difficult to emulsify in the past, and an aqueous emulsion of the rosin-based substance. The purpose is to provide a composition and a sizing agent. A sixth object of the present invention is a method for producing an aqueous emulsion of a rosin-based substance that achieves each of the above-mentioned objects and is excellent in storage stability and mechanical stability, an aqueous emulsion composition of the rosin-based substance, and the like. It is an object of the present invention to provide a papermaking sizing agent which exhibits excellent sizing performance using this. A seventh object of the present invention is to realize the above object with high efficiency, simplicity, and low cost.

【0005】

[Means for solving problems]

As a result of diligent research to achieve the above object, the present inventors have used a high-shear rotary emulsifier to mix an emulsifying dispersant and a heat-melted rosin-based substance, and the solids thereof. It has been found that the partial concentration, the emulsifier content and the mixing method have a selective effect, and that an emulsion having fine and uniform particles can be obtained by adding a step of diluting the mixture, and the present invention has been made. It was. In the present invention, (1), an aqueous emulsion dispersant and a rosin-based substance heated and melted are mixed under high shear using a high shear rotary emulsion disperser, and the solid content concentration is 60 to 90% by weight, total solid. A high-concentration mixture production step for obtaining a high-concentration mixture having an emulsion dispersant solid content content of 0.5 to 20% by weight in minutes, and a high-concentration mixture obtained through the high-concentration mixture production step are mixed with diluted water. A method for producing an aqueous emulsion of a rosin-based substance having an aqueous emulsion forming step of obtaining an aqueous emulsion in which the total solid content is adjusted to less than 60% by weight. It has a fixed stator and a rotating rotor that is paired with the stator and arranged to face each other, and a rosin-based substance that has been heat-melted with the emulsion dispersant aqueous solution is highly sheared using a high-shear rotary emulsion disperser. Mixing under shearing continuously supplies the emulsion dispersant aqueous solution and the heat-melted rosin-based substance to the high-shear rotary emulsion disperser, and causes both to be mixed by the high shearing force generated by the rotation of the rotor with respect to the stator. It provides a method for producing an aqueous emulsion of a rosin-based substance to be mixed. Further, in the present invention, (2), an aqueous emulsion dispersant solution and a heat-melted rosin-based substance are mixed under high shear using a high shear rotary emulsion disperser, and the solid content concentration is 60 to 90% by weight. The solid content of the emulsion dispersant in the total solid content is 0.

【0006】

The present invention will be described in detail below. In the present invention, the rosin-based substances include (A) rosins, (B) α, β-unsaturated carboxylic acid-modified rosins which are reaction products of rosins and α, β-unsaturated carboxylic acid derivatives. (C) Rosin esters obtained by esterification reaction between rosins and at least one of the group consisting of alcohols, phenols, epoxy compounds, etc., (D) The rosin esters and α, β-unsaturated carboxylic acids. Examples thereof include α, β-unsaturated carboxylic acid-modified rosin esters which are reaction products with acid derivatives, and mixtures of these rosin-based substances. Typical examples of the above (A) rosins include gum rosin, tall oil rosin and wood rosin, which are used alone or as a mixture of two or more kinds, and are disproportionated or hydrogenated to the above rosins. Rosin species also include those subjected to treatments such as aldehyde modification and polymerization alone or in combination of two or more. As the α, β-unsaturated carboxylic acid-modified rosins in (B) above, 1 to 20% by weight, preferably 3 to 18% by weight, of an acidic compound containing a -C = CC = O group is added to the rosins. It was made to do. Typical examples of the above acidic compounds include α, β-unsaturated carboxylic acid, its acid anhydride and the like. Specifically, fumaric acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, etc. Examples thereof include citraconic anhydride, acrylic acid and methacrylic acid, and the reaction method can be carried out by a known method.

【0007】

The rosin esters of (C) above are compounds obtained by an esterification reaction between rosins and at least one of the group consisting of alcohols, phenols, epoxy compounds and the like, and can be either complete or partially esterified. It may be a mixture thereof. As the alcohols, both monohydric alcohols and dihydric or higher polyhydric alcohols can be used, and trihydric and / or tetrahydric alcohols are particularly preferable, and these alcohols include, for example, glycerin, trimethylolethane, and trimethylol. Examples thereof include propane, 3-methylpentane-1,3,5-triol, pentaerythritol ester, and diglycerin. As the alcohols, two or more kinds of monohydric alcohols and divalent or higher polyhydric alcohols can be used in combination. As the phenols, both monovalent and divalent or higher polyhydric phenols can be used, and polyhydric phenols are particularly preferable, and examples thereof include hydroquinone, pyrogallol, and bisphenol A. The epoxy compound is a compound having an oxylane ring, and an epoxy resin such as a glycidyl ether type epoxy resin can be used. The esterification reaction between the rosins and the above compound can be carried out by a known method.

【0008】

Emulsification dispersants used for emulsification and dispersion of rosin-based substances include those that form protective colloids, such as various low-molecular-weight surfactants, high-molecular-weight emulsion dispersants, casein, polyvinyl alcohol, and modified starch. Can be used. In the method for producing an aqueous emulsion using a high shear rotary emulsifier according to the present invention, good emulsifying property can be obtained with any emulsifying dispersant, but the use of a polymer-based emulsifying dispersant is particularly emulsifying and aqueous emulsion. It is preferable in terms of stability, and it is also preferable in terms of the size performance of the sizing agent containing this aqueous emulsion. Examples of the polymer-based emulsion dispersant include so-called amphipathic polymers obtained by copolymerizing an anionic, cationic, or nonionic hydrophilic monomer and a hydrophobic monomer. For example, a partial or completely saponified product of a styrene- (meth) acrylic acid-based copolymer, a copolymer of an anionic or cationic monomer and a (meth) acrylic acid ester, an acrylamide-based copolymer, and the like can be exemplified. Further, cationic polyaminopolyamide-epichlorohydrin resin, alkylene polyamine-epichlorohydrin resin, poly (diallylamine) -epichlorohydrin resin and the like can be exemplified. Moreover, these may be used individually or in combination of 2 or more types.

【0009】

The method for producing a rosin-based emulsion of the present invention includes a high-concentration mixture production step and an aqueous emulsion production step. First, in the high-concentration mixture production step, the emulsion dispersant aqueous solution and the heat-melted rosin-based substance are mixed under high shear using a high-shear rotary emulsion disperser having a rotor and a stator, and the solid content concentration is 60. ~ 90% by weight, emulsification dispersant solid content content in total solid content is 0. Obtain a high concentration mixture of 5-20% by weight. As a high shear type rotary emulsification disperser having such a rotor and a stator, as a specific one actually used for uniformly mixing an aqueous emulsion dispersant solution and a heat-melted rosin-based substance at a high concentration, For example, the high-speed rotation high-shear stirring / dispersing machine and colloid mill described in "Dispersion Leology and Dispersion Technology" (p. 358, published by Shinzansha Cytec, published on May 20, 1991) can be mentioned. Further, in the present invention, it is preferable to continuously mix the aqueous emulsion dispersant solution and the heat-melted rosin-based substance, and the high-shear rotary emulsion disperser is preferably an in-line type. As a high-shear rotary emulsification / disperser that can be preferably used in practice, the rotor is rotated at high speed (thousands to tens of thousands of rpm) in a fixed ring (stator) close to the outer periphery of the stirring blade (rotor). It has a structure that can apply a shearing force to the fluid by supplying the fluid to the narrow gap, and the rotor has a structure that can rotate while maintaining a constant distance of several tens of μm to several tens of mm from the stator. In addition, on the surface where the rotor and the stator are close to each other, the rotor and / or the stator are provided with grooves, pores, long pores or comb teeth, and the rotation of the rotor exerts an impact force such as cavitation or pressure wave. Examples thereof include those having a structure capable of generating and more effectively applying a strong shearing force to a fluid existing in a limited area between a rotor and a stator. A plurality of rotor / stator pairs may exist inside the emulsification disperser. For example, a plurality of rotor / stator pairs exist in a planar or vertical shape on the same rotation axis, and each rotor / stator pair exists. A multi-stage structure that allows fluids to pass through in sequence gives a stronger shearing force than a single pair. A more preferable structure for a high-shear rotary emulsification / disperser is that a plurality of rings having a plurality of penetrating pores, long pores, or comb teeth having different diameters are provided on the same plane and concentrically at intervals. And the ring similar to the stator corresponding to the annular groove between the rings of these stators is concentric with the disk-shaped substrate.

【0010】

Schematically showing this, for example, as shown in FIG. 1, reference numeral 1 denotes a stator, and rings 3, 4, and 5 having large diameters are sequentially arranged inside the bottom of a bottomed cylindrical frame 2 so as to be separated from each other. One introduction pipe 6 is provided which is fixed and fixed, and which penetrates the bottom of the frame 2 and communicates with the innermost ring 3, and penetrates the bottom of the frame 2 between the rings 3 and 4. Then, the other introduction pipe portion 7 communicating between these rings is provided (one introduction pipe portion 6 and the other introduction pipe portion 7 communicating with each other in the ring 3 may be provided), and further, the frame 2 A lead-out pipe portion 8 is provided in the cylindrical portion so as to communicate with the gap between the inner wall of the frame body 2 and the ring 5. Reference numeral 11 denotes a rotor, and rings 13, 14, and 15 having large diameters are sequentially placed on the inner surface of the substrate 12 between the rings 3 and 4, between the rings 4 and 5, and between the ring 5 and the inner wall of the frame 2. A rotating shaft 16 is fixed to the center of the outer surface of the substrate 12, and the rotating shaft 16 is provided in a shaft hole (not shown) in the center of the frame plate 17. It is rotatably inserted. As shown in FIG. 2, the rings 3, 4, 5 of the stator 1 and the rings 13, 14 and 15 of the rotor 11 are centered on a ring body 18 made of a material that can withstand the temperature and impact of obtaining a mixture. The elongated holes 19, 19 ... In the height direction to face the ring body 18 are separated from each other and are provided on the entire circumference or a part thereof, or as shown in FIG. 3, toward the center thereof on the entire circumference or a part thereof. It has pores 20, 20 ... In this case, each ring of the stator 1 and each ring of the rotor 11 may both have elongated holes or pores, one may be an elongated hole, the other may be a pore, and vice versa, and the elongated hole may be used. The width of the holes and / or the diameter of the pores may be the same or different, and each ring of the stator 1 and each ring of the rotor 11 itself may be different or a combination of both in the same ring. The elongated hole may be a notch in which the entire height dimension of the ring body is cut out.

【0011】

Such a stator 1 and a rotor 11 have a rotating shaft in a state in which the respective rings are fitted and meshed with each other between the other rings, and the opening of the frame body 2 is appropriately sealed by a frame plate 17 by means. As 16 is rotated, each ring of the rotor 11 rotates with respect to each meshed ring of the stator 1, and for example, a heat-melted rosin-based substance is introduced from one introduction pipe portion 6 and the other. When the dispersant aqueous solution is introduced from the introduction tube portion 7, each ring has elongated pores and pores as shown in FIGS. 2 and 3, so that these flow out into the gaps of the meshed rings through the elongated pores and pores. It is mixed by receiving a shearing force in the rotational direction, which is also sequentially performed between the outer meshed rings, and the mixture is drawn out from the outlet pipe portion 8. The elongated hole shown in FIG. 2 is preferably a slit having a width of 0.1 to 5 mm, and the pore shown in FIG. 3 is preferably 0.1 to 5 mm. In the above-mentioned high-shear rotary emulsification / disperser, the rings forming each pair of the stator and the rotor are sequentially arranged in a plane, but may be sequentially arranged in a vertical shape, in which case each ring pair has the same diameter. However, in any case, the above can be applied mutatis mutandis. Commercially available high-shear rotary emulsion dispersers include in-line dispensing mixer (YSTRAL), Bockbolt homogenizer (Bockbolt), Milder (Ebara Corporation), ONLATOR (Co., Ltd.). Examples include Sakura Seisakusho), Pentax Mixer (Alfa Laval), SUPRATON (KRUPP), and CAVITRON (CAVITRON).

【0012】

By adjusting the solid content concentration of the mixture obtained by using the above-mentioned high shear rotary emulsification disperser to 60 to 90% by weight, the concentration of the emulsifying dispersant in the mixture system becomes high, and the mixture is emulsified with a rosin-based substance. The effect of facilitating homogenization of the dispersant component can be obtained. In addition, since the mixture of the rosin-based substance and the aqueous emulsion dispersant has a high viscosity and tends to be a non-uniform mixture, the emulsion disperser needs to be a high shear type, but excessive shearing causes heat generation of the mixture. Therefore, a shearing force that is uniformly mixed is required. From this point, the rotation speed of the rotor is preferably 1000 to 25000 rpm (rpm), the outermost peripheral speed of the rotor is preferably in the range of 3 to 100 m / sec, and the distance between the stator and the rotor is 0.05 to 10 mm. Is preferable. If the distance is less than 0.05 mm, the distance is narrow and the two may come into contact with each other, or the resistance to rotate the rotor by interposing the mixture in the gap becomes too high, causing inconvenience such as excessive heat generation. On the other hand, if the gap exceeds 10 mm, a uniform mixture cannot be obtained, and as a result, an emulsion having a fine particle size may not be obtained.

【0013】

In the case of the method for producing an aqueous emulsion using a conventional high-pressure discharge emulsifier or a high-shear rotary emulsion disperser, when the rosin-based substance and the emulsifier aqueous solution are mixed, the solid content concentration is equal to the product concentration, for example, a large amount. Even if it is 50% by weight, an oil-in-water emulsion is already formed, whereas in the method of the present invention, a rosin-based substance, an emulsion dispersant and a small amount of water are uniformly mixed in the high-concentration mixture production step. At this point, at least a stable oil-in-water emulsion has not been produced, and because it is a mixture under high shear, a high temperature is not always required to obtain a uniform mixture. Emulsification dispersants that are susceptible to thermal degradation or cannot be used in combination with rosin-based substances in ordinary aqueous media can also be used, and by being mixed with diluting water and diluted to a concentration of less than 60% by weight in the aqueous emulsion formation step. For the first time, a fine and stable oil-in-water emulsion is produced. In the high-concentration mixture production step using a high-shear rotary emulsifier / disperser, if the total solid content concentration is less than 60% by weight, the mixture of the rosin-based substance and the emulsifier aqueous solution becomes non-uniform, and the particle size is coarse. Since an oil droplet type emulsion in water is formed, an emulsion of uniform and fine particles cannot be obtained. On the other hand, if it exceeds 90% by weight, the emulsion dispersant aqueous solution becomes too high in concentration and viscosity, and is a rosin-based substance. Mixing with may be non-uniform, which is not practical. Multiple high-shear rotary emulsifiers and dispersers used in the high-concentration mixture production step can be connected in series, even if the solid content concentration of the mixture in each high-shear rotary emulsifier and disperser is the same. It can be changed in the range of 60 to 90% by weight.

【0014】

As a pre-step of the high-concentration mixture production step, the rosin-based substance is heated and melted in a tank equipped with a heating device, and has a viscosity of several hundred to several thousand centipoise (cps), and a high-concentration mixture production step with a metering pump. It is sent to a high shear type rotary emulsification disperser. The emulsion dispersant aqueous solution is emulsified and dispersed so that the emulsion dispersant solid content content is 0.5 to 20% by weight and the mixture solid content concentration is 60 to 90% by weight in the mixture obtained in the high concentration mixture production step. After adjusting the agent concentration, the temperature is adjusted to 10 to 130 ° C by a heat exchanger as necessary, and a predetermined amount is supplied to a high-shear rotary emulsion disperser by a metering pump to combine with the above-mentioned molten rosin-based substance. Mix. When the temperature of the emulsion dispersant aqueous solution is as low as less than 10 ° C, the temperature of the molten rosin-based material mixed in the high-shear rotary emulsion disperser drops sharply, resulting in a rapid increase in the viscosity of the rosin-based material. Due to solidification, it may be difficult to uniformly mix the rosin-based substance and the dispersant aqueous solution. Further, if the temperature of the aqueous emulsion dispersant solution exceeds 130 ° C., deterioration such as thermal decomposition of the emulsion dispersant component may occur. The temperature of the aqueous emulsion dispersant solution is preferably 20 to 90 ° C., it is not necessary to heat to the melting temperature of the rosin-based substance, and a relatively low temperature that does not cause thermal deterioration of the emulsion dispersant is preferable. The temperature after mixing the rosin-based substance and the dispersant aqueous solution is determined by the temperature, specific heat, mixing ratio, and mixing energy received from the high-shear rotary emulsification disperser of the rosin-based substance and the dispersant aqueous solution. The temperature is preferably 70 to 180 ° C, and if it is less than 70 ° C, the dispersion in the aqueous emulsion formation step becomes insufficient and coarse particles may be formed. If the temperature is higher than 180 ° C, the dispersant component and the rosin-based substance may be formed. Thermal deterioration may occur. If the solid content of the emulsifying dispersant is less than 0.5% by weight of the total solid content, an emulsion having a fine particle size cannot be obtained, and if it is more than 20% by weight, the foamability of the emulsion becomes high and the cost is reduced. It will also be disadvantageous.

【0015】

In the present invention, the emulsion dispersant aqueous solution supplied from the metering pump and the rosin-based substance in the molten state are provided by separate separate supply pipes (separate lines), especially when the temperature of the emulsion dispersant aqueous solution is low. It is preferably supplied into a high shear type rotary emulsification disperser. As described in Japanese Patent Application Laid-Open No. 8-117578, a method in which an aqueous emulsion dispersant solution and a rosin-based substance in a molten state are merged before being processed by a high-speed rotary emulsifier is a rosin-based substance. If the temperature difference between the emulsion and the emulsifying dispersant aqueous solution is large, the rosin-based substance is rapidly cooled and solidified, resulting in non-uniform mixing at the time of merging, deterioration of emulsifying property, and the inability to obtain an aqueous emulsion having a fine particle size. Problems arise. In actual emulsification, there are optimum conditions for the types of rosin-based substances and emulsifiers, the supply temperature of the rosin-based substances and the aqueous emulsifier solution, the mixed concentration thereof, and the shearing force at the time of mixing, depending on the combination thereof.

【0016】

In the present invention, in the aqueous emulsion forming step, the total solid content of the high-concentration mixture having a solid content concentration of 60 to 90% by weight, which is the total of the emulsion dispersant and the rosin-based product obtained in the high-concentration mixture forming step, is 60%. Dilute to less than. The temperature of the diluted water used for this dilution (which may contain at least one pH regulator such as salt, acid, alkali, or other polymer substance that contributes to the stabilization of the emulsion) is adjusted by a heat exchanger. It is preferably supplied at 20 to 130 ° C. If the temperature of the diluted water is too low, depending on the composition of the rosin-based substance and the aqueous emulsifier solution, there arises a problem that the mixture of both in high concentration is partially solidified by the temperature shock or undispersed substances are generated. The method of mixing the diluted water may be either a batch method or a continuous method. In the case of the batch type, the mixture derived from the high-shear rotary emulsion disperser is stored in a dilution tank under the same conditions as the temperature and pressure in the high-shear rotary emulsion disperser in the high-concentration emulsion production step, and a predetermined amount of diluted water is added. Add and stir to mix. In the case of the continuous type, the water used for dilution is supplied by a metering pump, and a static in-line mixer ("Statec Mixer" (trade name of Noritake Company Limited product), "Hi-Mixier (product of Toray)" Name), "Skaya mixer (trade name of Sakura Seisakusho's product)))), rotary emulsification disperser (propeller mixer, turbine mixer, resolver), high shear rotary emulsification disperser, etc. The mixture is sequentially mixed with the mixture sequentially derived from the high-shear rotary emulsion disperser, and it is preferable to use a high-shear rotary emulsion disperser similar to that used in the high-concentration mixture production step. The emulsion obtained by performing the above is cooled to room temperature by a cooler and taken out.

【0017】

The aqueous emulsion of the rosin-based substance obtained by such a method is fine particles having an average particle size of 0.6 μm or less (not larger than 0.6 μm), and further coarse particles having an average particle size of 1 μm or more (not smaller than 1 μm). Is characterized by being 1% by weight or less (1% by weight at most) or not contained. It is considered that this is because the present invention has a high-concentration mixture production step and an aqueous emulsion production step, and at least a homogeneous mixture was obtained by using a high-concentration rotary emulsion disperser in the high-concentration mixture production step. Be done. An emulsion having a fine particle size may be obtained by a conventional known emulsification method, but the emulsion often contains coarse particles of 1 μm or more, and the coarse particles are obtained by filtering the obtained aqueous emulsion. It may cause clogging when it is made into a product, or it may become a sediment in the product, and if a sizing agent containing these coarse particles is used in the paper making process, it may cause a stain problem on the paper machine. There is sex. The rosin-based emulsion sizing agent for papermaking containing the aqueous emulsion obtained by the present invention reduces stains in the papermaking system, has excellent size performance, has less precipitate in the product, and has mechanical stability. Has the characteristic of being excellent.

【0018】

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIG. 4, the emulsifier and water are mixed with the rosin-based substance supply unit 21 that can supply the rosin-based substance melted in a kettle equipped with a heating device at a constant flow rate by a metering pump, and adjusted to an arbitrary emulsifier concentration. Further, an emulsifier aqueous solution supply unit 22 capable of supplying an emulsifier aqueous solution adjusted to an arbitrary temperature by a heat exchanger at a constant flow rate by a metering pump is provided, and a high-concentration mixture of a rosin-based substance and an emulsifier aqueous solution melted from each supply unit is generated. It is supplied to step 23 and mixed by a high shear type rotary emulsifier / disperser having a structure of a main part shown schematically in FIGS. 1 to 3 and specifically shown in FIG. 5, for example. In the device shown in FIG. 5, the stator 31 has nozzles (diameter 0.6 to 1.5 mm) on the entire peripheral wall, and the sequentially large rings 32, 33, 34, and 35 have a frame body not shown. On the other hand, the rotor 41 is fitted between the rings 32 and 33 and between the rings 33 and 34 with a sequentially large diameter provided with slits (width 0.6 mm) at equal intervals on the entire circumference. Rings 43 and 44 and a ring 45 having a nozzle (diameter 0.6 to 1.5 mm) on the entire peripheral wall fitted between the rings 34 and 35, and further rotating as shown in FIG. A shaft and a frame plate are provided, and the stator 31 and the rotor 41 are sealed as shown in FIG. In this state, the rings 43 to 45 are alternately opposed to the rings 32 to 35, but the rotor 41 is rotated (rotation speed 1000 to 10000 rpm, average peripheral speed of the rotor ring 3. 9 ~ 40m / sec), these rings 43 ~ 45 rotate with respect to the rings 32 ~ 35, and the molten rosin substance and emulsion dispersant aqueous solution supplied from the inlets 36 and 37 of the stator 31 respectively are described above. Each time the mixture flows out through the nozzle and slit of the ring, both are mixed by receiving a shearing force due to rotation, and although not shown, the mixture is taken out from the lead-out portion corresponding to the lead-out pipe portion 8 in FIG. This high-shear rotary emulsion disperser may be used alone, but a plurality of units may be used, and the mixture obtained by the high-shear rotary emulsion disperser in the previous stage may be directly applied to the high-shear rotary emulsion disperser in the subsequent stage, for example. It may be passed through the introduction port 36 only, or the mixture may be passed through the introduction port 36 again, and at the same time, the emulsifier aqueous solution or the diluted water may be passed through the introduction port 37. The mixture obtained in the high-concentration mixture production step has a solid content concentration of 60 to 90% by weight (solid content of rosin-based substance and emulsifier), and the concentration of the emulsion dispersant solid content with respect to the total solid content is 3 to 6% by weight. The temperature at which the mixture is performed is 130 to 160 ° C for the molten rosin-based substance and 20 to 90 ° C for the aqueous emulsifier solution, and the molten rosin-based substance and the emulsifier aqueous solution are continuously mixed under these conditions. Will be done.

【0019】

The mixture having a temperature of 110 to 150 ° C obtained in the high-concentration mixture production step is supplied to the aqueous emulsion production step 24, where it is supplied from the diluted water supply unit 25 capable of supplying the diluted water whose temperature has been adjusted by the temperature controller. It is mixed with diluted water having a temperature of 20 to 90 ° C and diluted to a solid content of 30 to 60% by weight. At this time, the configuration is different between the case of continuous dilution and the case of non-continuous dilution, but in the case of continuous dilution, the amount is quantified from the high-concentration mixture generation step 23 and the diluted water supply unit 25. Using a mixer that can continuously mix the mixture and diluted water supplied at a constant flow rate by a pump, for example, the high-shear rotary emulsion disperser used in the high-concentration mixture generation step, the mixture is introduced into the inlet 36 in FIG. Dilute water is supplied to the mouth 37, and both are mixed and diluted. In addition, a stationary in-line mixer is used to continuously mix according to this. In the case of discontinuous dilution, the mixture obtained in the high-concentration mixture production step and the diluted water are supplied to a dilution tank equipped with a stirrer and mixed by stirring.

【0020】

The high-concentration mixture production step 23, the aqueous emulsion production step 24, and the heating steps of the emulsifier aqueous solution supply unit 22 and the diluted water supply unit 25 are added so that the water does not boil violently when each step is carried out. Perform under reduction. As shown in FIG. 4, the aqueous emulsion obtained in the aqueous emulsion forming step 24 is cooled to room temperature and normal pressure in the cooling / depressurizing section 26 and depressurized, and the aqueous emulsion of the product is obtained from the taking-out section 27. This aqueous emulsion is used as it is as a sizing agent, but additives may be added.

【0021】

As the rosin-based substance, fumaric acid-enhanced rosin having a melting temperature of 130 to 170 ° C, a polyhydric alcohol ester of rosin, a mixture of maleic anhydride-enhanced rosin and rosin polyhydric alcohol ester, or a maleic anhydride-enhanced rosin ester, respectively. As the emulsifying dispersant used, styrene- (meth) acrylic acid-based (copolymer in which styrene and (meth) acrylic acid are essential components and other vinyl-based monomers may be copolymerized) anionic polymer-based Emulsifier, acrylamide-based (copolymer in which (meth) acrylamide and anionic monomer are essential components and other vinyl-based monomers may be copolymerized) Anionic polymer-based emulsifier or acrylamide-based cationic polymer-based emulsifier (A copolymer in which (meth) acrylamide and a cationic monomer are essential components and other vinyl-based monomers may be copolymerized) is used.

【0022】

The operation of the device of FIG. 5 is as shown in FIG. 6 when viewed from the introduction port 36 side for the rings 43 and 44 of the rotor 41 and the ring 33 of the stator 31, for example, the slits 51 of the rings 43 and 44 and the nozzles of the ring 33. There is a flow due to centrifugal force in 50, and the rotor rotates at high speed in the chamber 52 in the gap between the ring of the rotor and the stator (for example, the molten rosin-based substance and the aqueous emulsion dispersant in the high-concentration mixture production step). The chamber receives centrifugal force and flows outward in the radial direction through the chamber, while the chamber repeatedly contains and opens the centrifugal flow of the treatment liquid due to the displacement of the rotor and stator rings and the nozzle, and this time differential pressure ΔP is increased. appear. Further, a shearing force acts on the processing liquid in the minute gap 53 between the rotor and the stator. The impact force due to the collision of these flows produces a strong stirring and crushing effect (partially quoted from the "Cavitron" catalog). The same applies to other rings. At this time, in the high-concentration mixture production step, the rosin-based substance and the aqueous emulsion dispersant are separately supplied to the high-shear rotary emulsifier, so that the two are brought into contact with each other in a high-shear force field, so that the mixing is uniform. In addition, the solid content concentration of the mixed solution is in the range of 60 to 90% by weight, and the concentration of the emulsion dispersant solid content in the total solid content is 0. By setting the content in the range of 5 to 20% by weight, a more homogeneous mixture of the two is performed (an emulsion having a narrow distribution with an overwhelmingly large number of fine particles with a small number of coarse particles can be obtained) and a small amount of water. By limiting the amount ratio of the rosin-based substance and the solid content of the emulsifying dispersant, it is easy to mix the two homogeneously, so the degree of need to raise the temperature is small, and it is easy to deteriorate due to heat. It is also possible to use a difficult rosin-based substance and an emulsion dispersant in combination. Then, after obtaining such a uniform high-concentration mixture, an aqueous emulsion forming step is provided, and by diluting the mixture here so that the solid content concentration is within the range of less than 60% by weight, the particle size is small and the distribution is narrow. An aqueous emulsion of the product can be obtained. The same can be said for the device shown in FIG. 5 for the devices shown in FIGS. 1 to 3 and other modified devices described above.

【0023】

[Example]

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto. In addition, parts and% in each embodiment are based on weight. First, the materials used in Examples and Comparative Examples are manufactured as follows. Production Example 1 (Production of fumaric acid-enriched rosin-based substance) Gradually add 90 parts of fumaric acid to 440 parts of gum rosin that is in a molten state at 200 ° C, stir and keep warm at 200 ° C for 2 hours, and then add 470 parts of formaldehyde-treated (transformation rate 1%) tall oil rosin to melt. The mixture was stirred and homogeneously mixed, after which the resulting reaction product was cooled to room temperature. This reaction product is a fumaric acid-enriched rosin with 9% fumaric acid added.

【0024】

Production Example 2 (Production of polyhydric alcohol ester of rosin substance) In a 1 liter volume flask equipped with a stirrer, a thermometer, a nitrogen introduction tube, a water diversion device and a cooler, 600 parts of gumrosin having an acid value of 170 and 55 parts of glycerin were placed and subjected to an esterification reaction at 270 ° C for 15 hours. A reaction product of a polyhydric alcohol ester of a rosin substance was obtained.

【0025】

Production Example 3 (Production of maleic anhydride-enhanced rosin and rosin ester mixture) 7 parts of maleic anhydride is added to 43 parts of gum rosin in a molten state at 200 ° C, and after stirring and keeping warm at 200 ° C for 2 hours, 50 parts of the rosin ester of Production Example 2 is added and mixed by stirring in a molten state, and maleic anhydride is added. A mixture of acid-fortified rosin and rosin esul in a 1: 1 weight ratio was obtained.

【0026】

Production Example 4 (Production of maleic anhydride-enhanced rosin ester) 93 parts of the rosin ester glycerin ester obtained in Production Example 2 was heated to 200 ° C and melted, 7 parts of maleic anhydride was added, and the mixture was heated and kept warm at 200 ° C for 3 hours to generate maleic anhydride, which is a reaction product of maleic anhydride. An acid-enhanced rosin ester was obtained.

【0027】

Production Example 5 (Production of styrene-methacrylic acid-based anionic polymer-based emulsion dispersant) 50 parts of styrene, 30 parts of methacrylic acid, 10 parts of acrylic acid, 10 parts of lauryl acrylate, 1 part of ammonium persulfate and 225 parts of water are stirred and mixed in a 1 liter volume pressure resistant flask equipped with a stirrer, a thermometer and a nitrogen gas introduction tube. Then, it was heated at 150 ° C. for 2 hours. Then, cool to 60 ° C, gradually add 35.5 parts of 48.5% sodium hydroxide, stir for 30 minutes, and then cool to room temperature to make a styrene-methacrylic acid anionic solution, which is a polymer dispersion with a solid content of 30%. A polymer-based emulsion dispersant was obtained.

【0028】

Production Example 6 (Production of cationic polymer-based emulsion dispersant for Examples) A polymer-based emulsion dispersant was produced as follows according to the method for producing cationic poly (meth) acrylamide having a hydrophobic group in Examples of JP-A-3-227481. In a 1 liter volume four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction tube, 31.4 parts of dimethylaminoethyl methacrylate, 85.3 parts of 50% acrylamide aqueous solution, 20.8 parts of styrene, 100.6 parts of ion-exchanged water, 143.3 parts of isopropyl alcohol and 0.6 parts of n-dodecyl mercaptan were charged, and the pH was adjusted to 4.5 with a 20% aqueous acetic acid solution. The temperature of this mixed solution was raised to 60 ° C. under a nitrogen gas atmosphere while stirring. 2.3 parts of a 5% aqueous solution of ammonium persulfate was added as a polymerization initiator, the temperature was raised to 80 ° C., and the mixture was held for 1.5 hours, and then 0.7 part of a 5% aqueous solution of ammonium persulfate was added. After keeping the temperature at the same temperature for another 1 hour, isopropyl alcohol was distilled off, and water was further added to obtain a cationic polymer emulsion dispersant which is a polymer solution having a solid content concentration of 30%.

【0029】

Production Example 7 (Production of anionic polymer-based emulsion dispersant for examples) 19 parts of normal butyl methacrylate, 96 parts of 50% acrylamide aqueous solution, 8 parts of 80% acrylic acid aqueous solution, ion-exchanged water in a 1-liter volume four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction tube. 83 parts, 88 parts of isopropyl alcohol, and 0.9 parts of n-dodecyl mercaptan were charged, and the temperature was raised to 60 ° C. under a nitrogen gas atmosphere while stirring and mixing the mixed solution. 0.14 parts of azobisisobutyronitrile was added as a polymerization initiator, the temperature was raised to 80 ° C., and the mixture was held for 2 hours, then ion-exchanged water was added, and then isopropyl alcohol was distilled off to obtain a polymer having a solid content concentration of 35%. An anionic polymer emulsion dispersant as a solution was obtained.

【0030】

Example 1 According to the step shown in FIG. 4, in the rosin-based substance supply unit 21, the fumaric acid-enhanced rosin obtained in Production Example 1 is melted at 150 ° C., and the melted fumaric acid-enhanced rosin is held at 150 ° C. Further, in the emulsifier aqueous solution supply unit 22, the anionic polymer-based emulsion dispersant obtained in Production Example 5 is continuously diluted with water in the line, and the amount of the emulsion dispersant and the solid mixture in the high-concentration mixture production step. After adjusting the solid content concentration so that the component concentration becomes a predetermined value, the mixture is heated by a heating device so that the temperature becomes 80 ° C. Next, in the high-concentration mixture production step 23, the Cavitron CD-1010 is used as a high-slit rotary emulsifier, and the Cavitron CD-1010 has the stator and rotor of both the stator and rotor rings shown in FIG. A slit with the same shape as the slit in the figure and a width of 0.6 mm is formed, and the peripheral speed of the outermost ring of the rotor is 3. Operate at 9 m / sec and rotor speed of 1000 rpm. Under such operating conditions, the melted emulsifier held at 150 ° C by a metering pump from the rosin-based substance supply unit 21 at each of the inlets 36 and 37 shown in FIG. While supplying the fortified rosin, the emulsifier aqueous solution supply unit 22 adjusts the emulsion dispersant to 5% in the high-concentration mixture production step and the solid content concentration of the mixture to 76%, and adjusts the concentration to 80 ° C. A heated emulsifier aqueous solution is supplied by a metering pump, both are mixed in this emulsifier based on the above-mentioned action, and a mixture of fumaric acid-enriched rosin and an emulsifier aqueous solution is sequentially delivered from an outlet corresponding to the introduction pipe portion 8 in FIG. Take out. The mixture thus obtained had a solid content concentration (total of the solid content of the emulsion dispersant and the fumaric acid-enriched rosin) of 76% and a temperature of 110 ° C. Next, the mixture is diluted in the aqueous emulsion forming step 25, and here, the above-mentioned mixture obtained in the high-concentration mixture forming step 23 (temperature 110 ° C.) is placed in a dilution tank with a stirrer so as to perform discontinuous mixing. In addition to accommodating 500 g of C), 585 g of water at 90 ° C prepared in advance in the diluted water supply unit 24 is supplied, and the mixture is stirred and mixed for 30 minutes. Then, it was cooled with stirring to obtain an aqueous emulsion of a rosin-based substance as a product. The obtained aqueous emulsion had a solid content concentration of 35%, a solid content of the emulsion dispersant in the total solid content of 5%, and an average particle size of 0.45 μm.

【0031】

Example 2 In Example 1, the solid content of the emulsion dispersant was 4% of the total solid content, the solid content concentration of the mixture obtained through the high-concentration mixture production step was 72%, and the solid content of the emulsion obtained through the aqueous emulsion production step was 72%. The minute concentration is 40%, the peripheral speed of the outermost ring of the rotor of Cavitron CD-1010 is 23 m / sec, the rotation speed of the rotor is 6000 rpm, and a static mixer (two liquids to be mixed) is used in the aqueous emulsion formation process. Using a mixer) that supplies each at a constant flow rate and mixes them in the line, continuous mixing is performed to mix and disperse the mixture that is sequentially taken out in the high-concentration mixture generation step and water at 90 ° C while supplying a constant flow rate. An aqueous emulsion of a rosin-based substance having an average particle size of 0.40 μm was obtained in the same manner except for the above.

【0032】

Example 3 In Example 2, the solid content of the emulsion dispersant was 3% of the total solid content, the solid content concentration of the mixture obtained through the high-concentration mixture production step was 67%, and the solid content of the emulsion obtained through the aqueous emulsion production step was 67%. The fraction concentration was set to 50%, the stator and rotor of the Cavitron CD-1010 were changed to a nozzle type in which each ring had pores with a diameter of 0.6 mm on the entire circumference, and the peripheral speed of the outermost ring of the rotor was 39 m / sec. The rotation speed of the rotor is set to 10000 rpm, and the peripheral speed of the outermost ring of the rotor is set to 23 m / sec and the rotation speed of the rotor is increased by using the Cavitron CD-1010 having the same configuration as that used in Example 1 in the aqueous emulsion formation step. The mixture was continuously mixed at 6000 rpm, and an aqueous emulsion of a rosin-based substance having an average particle size of 0.25 μm was obtained in the same manner as in the high-concentration mixture production step of Example 2.

【0033】

Example 4 In Example 3, the temperature of the emulsifier aqueous solution in the high-concentration mixture production step was set to 120 ° C., two liquids of the emulsifier aqueous solution and the molten rosin-based substance were mixed into one liquid in the same tube, and this mixed liquid was mixed with Cavitron CD. An aqueous emulsion of a rosin-based substance having an average particle size of 0.40 μm was obtained in the same manner except that it was supplied to -1010.

【0034】

Example 5 In Example 3, the average particle size is 0.35 μm in the same manner except that a nozzle type having a pore diameter of 1.5 mm for each ring was used as the stator and rotor of the Cavitron CD-1010 used in the high-concentration mixture generation step. An aqueous emulsion of the rosin-based substance of

【0035】

Example 6 In Example 3, two Cavitron CD-1010s were connected in series in the high-concentration emulsion production step, and the mixed solution obtained sequentially from the first unit was supplied from the introduction port corresponding to the introduction port 36 of FIG. 5 of the second unit. The solid content concentration of the mixed solution obtained from the second unit was 61%, the temperature at the time of supplying the emulsion dispersant aqueous solution was 40 ° C, and the peripheral speed of the outermost ring of the rotor was 31 m / sec for both units. An aqueous emulsion of a rosin-based substance having an average particle diameter of 0.20 μm was obtained in the same manner except that the rotor rotation speed was set to 8000 rpm.

【0036】

Example 7 In Example 3, the maleic anhydride-enhanced rosin obtained in Production Example 3 and the rosin ester mixture were used as the rosin-based substance, and the cationic polymer emulsification dispersant obtained in Production Example 6 was used as the emulsification dispersant. , The temperature at the time of supplying the rosin-based substance is 140 ° C, the temperature at the time of supplying the emulsion of the emulsion dispersant is 30 ° C, the temperature at the time of supplying the diluted water is 25 ° C, and the solid content of the emulsion dispersant is total solid. Average particles in the same manner except that the solid content concentration of the mixture obtained through the high-concentration mixture production step was 82% and the solid content concentration of the emulsion obtained through the aqueous emulsion production step was 45%. An aqueous emulsion of a rosin-based substance having a diameter of 0.28 μm was obtained.

【0037】

Example 8 In Example 3, the maleic anhydride-enhanced rosin obtained in Production Example 3 and the rosin ester mixture were used as the rosin-based substance, and the anionic polymer emulsification dispersant obtained in Production Example 7 was used as the emulsification dispersant. , The temperature at the time of supplying the rosin-based substance is 140 ° C, the temperature at the time of supplying the emulsion of the emulsion dispersant is 40 ° C, the temperature at the time of supplying the diluted water is 60 ° C, and the solid content of the emulsion dispersant is total solid. 5% in minutes, 89% solid content concentration of the mixture obtained through the high-concentration mixture production process, 31 m / sec peripheral speed of the outermost ring of the rotor of Cavitron CD-1010 in the same process, rotor rotation speed An aqueous emulsion of a rosin-based substance having an average particle size of 0.25 μm was obtained in the same manner except that the solid content concentration of the mixture obtained through the aqueous emulsion formation step was 45% at 8000 rpm.

【0038】

Example 9 In Example 3, the maleic anhydride-enhanced rosin ester obtained in Production Example 4 was used as the rosin-based substance, and the anionic polymer emulsification dispersant obtained in Production Example 5 was used as the emulsion dispersant. The temperature at the time of supplying the substance is 160 ° C, the temperature at the time of supplying the emulsion of the emulsion dispersant is 60 ° C, the temperature at the time of supplying the diluted water is 80 ° C, and the solid content of the emulsion dispersant is 6 in the total solid content. %, Average particle size in the same manner except that the solid content concentration of the mixed solution obtained through the high-concentration mixture forming step was 85% and the solid content concentration of the mixed solution obtained through the aqueous emulsion forming step was 50%. An aqueous emulsion of 0.23 μm rosin-based material was obtained.

【0039】

Example 10 In Example 4, the high-concentration rotary emulsifier used in the high-concentration mixture production step was replaced with Pockbolt 100 type (manufactured by Bockbolt), the peripheral speed of the rotor was 19 m / sec, and the rotation speed of the rotor was 3000 rpm. An aqueous emulsion of a rosin-based substance having an average particle size of 0.42 μm was obtained in the same manner except that the solid content concentration of the mixture obtained in the high-concentration mixture production step was 72%.

【0040】

Comparative example 1 In Example 3, by setting the solid content concentration in the high-concentration mixture forming step to 50%, an aqueous dispersion that had undergone the high-concentration mixture forming step was obtained, and the average was obtained in the same manner except that the aqueous emulsion forming step was not performed. An aqueous emulsion of a rosin-based substance having a particle size of 1.8 μm was obtained.

【0041】

Comparative example 2 In Example 3, the same operation was performed except that the solid content concentration of the emulsion in the aqueous emulsion forming step was set to 62%, but the emulsion solidified in the cooling / depressurizing part and blocked the production line, so that the aqueous emulsion of the rosin-based substance was blocked. Was not obtained.

【0042】

Comparative example 3 In Example 3, the average particle size was 1.5 in the same manner except that the solid content concentration of the mixture in the high-concentration mixture production step was 55% and the solid content concentration of the emulsion obtained in the aqueous emulsion production step was 50%. An aqueous emulsion of μm rosin-based material was obtained.

【0043】

Comparative example 4 In Example 7, the temperature when the rosin-based substance was supplied was 160 ° C, the temperature when the emulsion dispersant aqueous solution was supplied was 150 ° C, the solid content of the emulsion dispersant was 5% of the total solid content, and a high-concentration mixture was produced. The solid content concentration of the dispersion in the process is 45%, and in the aqueous emulsion formation process, a gorin homogenizer, which is a high-pressure discharge emulsifier, is used. /cm²A dispersion liquid of a rosin-based substance containing 1.3% of an average particle size of 0.45 μm and a particle size of 1 μm or more was obtained in the same manner except for the treatment under the pressure of.

【0044】

Comparative example 5 In Example 9, the temperature at the time of supplying the rosin-based substance was 180 ° C, the temperature at the time of supplying the aqueous emulsion dispersant solution was 160 ° C, and a gorin homogenizer, which is a high-pressure discharge emulsifier, was used in the aqueous emulsion formation step. 600Kgf / cm at a solid content concentration of 50%, which is the same as the solid content concentration in the high-concentration mixture (preliminary dispersion) production process.²When the treatment was carried out in the same manner except that the treatment was carried out under the pressure of, an aqueous emulsion of a rosin-based substance containing 1.1% of an average particle size of 0.40 μm and a particle size of 1 μm or more was obtained. Due to the deterioration of the seal part of the Gorin homogenizer, the particle size increases with the progress of Was done.

【0045】

Comparative example 6 Using a pressure-resistant flask with a stirring blade capable of heating and cooling, the rosin-based substance obtained in Production Example 3 was heated and melted at about 150 ° C., and while stirring, the high cationicity obtained in Production Example 6 was obtained. A molecular emulsification dispersant was added so as to have a total solid content of 7% and mixed to obtain a water-in-oil emulsion. Under stirring, hot water was gradually added to the phase inversion to form an oil-in-water emulsion, and hot water was quickly added and mixed to obtain a stable oil-in-water emulsion, which was then cooled to room temperature. In this way, an aqueous emal of a rosin-based substance containing an average particle size of 0.48 μm and a particle size of 1 μm or more at 1.5% was obtained.

【0046】

Comparative example 7 Using a pressure-resistant flask with a stirring blade capable of heating and cooling, the rosin-based substance obtained in Production Example 4 was heated and melted at about 160 ° C, and while stirring, the anionic high amount obtained in Production Example 5 was obtained. A molecular emulsification dispersant was added so as to have a total solid content of 10% and mixed to obtain a water-in-oil emulsion. Under stirring, hot water was gradually added to the phase inversion to form an oil-in-water emulsion, and hot water was quickly added and mixed to obtain a stable oil-in-water emulsion, which was then cooled to room temperature. In this way, an aqueous emal of a rosin-based substance containing an average particle size of 0.73 μm and a particle size of 1 μm or more at 10% was obtained. The main production conditions of the above Examples and Comparative Examples are briefly summarized in Tables 1 and 2, and the particle sizes of the obtained aqueous emulsions described in each of these Examples and Comparative Examples are summarized in Tables 1 and 2. Shown.

【0047】

[table 1]

【0048】

[Table 2]

【0049】

In contrast to 5 μm, in Comparative Example 1, the solid content concentration in the high-concentration mixture production step is too low, so that an aqueous dispersion is generated in this step, which is substantially high. This step is the "aqueous emulsion forming step" without going through the "concentration mixture forming step", and it is shown that the rosin-based substance and the emulsified aqueous solution are not uniformly mixed and fine dispersed particles cannot be obtained. In Example 2, the solid content concentration in the "aqueous emulsion forming step" is too high and solidifies. In Comparative Example 3, even if the solid content concentration in the "aqueous emulsion forming step" is appropriate, the solid content concentration in the "high concentration mixture forming step" Is too low, the result is similar to that of Comparative Example 1. In Comparative Example 4, it corresponds to the case where the one of Example 7 is emulsified by the high temperature and high pressure emulsification method. , And the "water-based emulsion production step" was emulsified as a "fine particle step" using a high-pressure discharge emulsifier, but it is shown that only an emulsion having a larger particle size than that of Example 7 can be obtained. Further, in Comparative Example 5, Example 9 was emulsified by the same high-temperature and high-pressure emulsification method as in Comparative Example 4, but as compared with Example 9, only those having a larger particle size were obtained, and the emulsification temperature was higher. Since it is too high, the seal part of the emulsifier deteriorates, indicating that stable production is difficult. Comparative Examples 6 and 7 were combinations of the rosin-based substance and the emulsification dispersant of Examples 7 and 9, respectively, and emulsification was performed by the phase inversion emulsification method using a large amount of the emulsification dispersant, but the amount of the emulsifier used was increased. However, only an emulsion having a larger particle system than that of each example was obtained, and this tendency was particularly remarkable in the case of Comparative Example 7. The aqueous emulsion of the rosin-based substance of the example can be used regardless of the type of the emulsion dispersant and the type of the rosin-based substance. As a result, an aqueous emulsion of a rosin-based substance, which is more productive than the conventional method for obtaining an aqueous emulsion of a rosin-based substance and has a dispersion having a fine particle size, can be obtained. Of each rosin-based substance obtained in the above Examples and Comparative Examples Table 2 shows the results of the size effect test, the mechanical stability test, and the static stability test using the aqueous emulsion composition. The test conditions are as follows.

【0050】

(Size effect test 1) Dilute bleached kraft pulp (mixed pulp with a softwood hardwood pulp ratio of 1: 9) with water for dilution with a hardness of 100 ppm so that the pulp concentration is 2.5%, and use a beater to dilute 400 ml Canadian. I beat up to standard freeness. Next, 1.2 liters of the obtained pulp slurry was weighed in a disintegrator, and after stirring, 1.5% of van sulphate was added to the pulp, and then an aqueous emulsion of rosin-based substances obtained from each of the above Examples and Comparative Examples was applied. 0.2% of pulp was added separately for each. Then, the obtained pulp slurry was diluted to a concentration of 0.25% with diluted water having a pH of 4.5, and cationic polyacrylamide (Paper Machinery Strengthening Agent DS410, Nippon PMC Co., Ltd.) was added as a fixing agent to 0.05% of pulp. Add and make paper with a Noble and Wood paper machine at pH 4.5, and dry the obtained wet paper at 100 ° C for 100 seconds using a drum dryer, with a basis weight of 65 g / m.²The test papers of the above-mentioned Examples and Comparative Examples were obtained. Each of the obtained test strips was adjusted for 24 hours in a constant temperature and humidity (20 ° C, relative humidity 65%) environment, and then the degree of size was measured by the Stekicht method. This sizing method was performed only on aqueous emulsions of rosin-based substances (Examples 1 to 6, 10 and Comparative Examples 1 to 3) using the rosin-based substance obtained in Production Example 1.

【0051】

(Size effect test 2) 1.2 liters of pulp slurry obtained by beating under the same conditions as the above size effect test 1 is weighed in a disintegrator, and light calcium carbonate (Tamapearl 121S manufactured by Okutama Kogyo Co., Ltd.) is added under stirring. After adding 3.0% to pulp, 1.0% to pulp, and 0.2% to pulp of the paper strength enhancer DS410, aqueous emulsions of rosin-based substances obtained from each of the above Examples and Comparative Examples were added. Separately, 0.4% of pulp was added. Then, the obtained pulp slurry was diluted to a concentration of 0.25% with diluted water at pH 8, and the above-mentioned light calcium carbonate was further added to 5% of pulp, and high molecular weight cationic polyacrylic abad was added to 0.01% of pulp as a yield agent, and noble was added. Paper is made with an Andwood paper machine at pH 8 and the obtained wet paper is dried using a drum dryer at 100 ° C for 80 seconds and has a basis weight of 65 g / m.²The test papers of the above-mentioned Examples and Comparative Examples were obtained. Each of the obtained test strips was adjusted for 24 hours in a constant temperature and humidity (20 ° C, relative humidity 65%) environment, and then the degree of size was measured by the Stekicht method. This sizing method was performed only on aqueous emulsions of rosin-based substances (Examples 7 to 9, Comparative Examples 4 to 7) using the rosin-based substances obtained in Production Examples 3 and 4.

【0052】

(Standing stability test) 100 ml of emulsion compositions of the rosin-based substances of the above Examples and Comparative Examples were placed separately in a test tube having a length of 30 cm and an inner diameter of 2.1 cm, and after standing for 2 months, they settled on the bottom. The height (mm) of the precipitate was measured.

【0053】

(Mechanical stability test) 50 g of the emulsion composition of each rosin-based substance of the above Examples and Comparative Examples was separately placed in a cup, and a Marlon-type stability test was performed at a temperature of 25 ° C., a load of 25 kg, and a rotation speed of 800 rpm for 10 minutes. Was done. The agglomerates formed for each cup were filtered through a 325 mesh wire mesh, and the amount of precipitation with respect to the total solid content for each cup was measured and expressed as a percentage.

【0054】

[Table 3]

【0055】

From the above results, when the aqueous emulsion composition of the rosin-based substance of the example was used as the sizing agent, both the size effect test and the stability test of the sizing agent were superior to those of the comparative example, and the emulsifying property was improved. It turns out to be excellent.

【0056】

[Effect of the invention]

According to the present invention, unlike the solvent method, there is no adverse effect on the environment or problems in occupational safety and health, and when a rosin-based substance having a particularly high softening point is used as in the high-temperature and high-pressure method. It is difficult to obtain an emulsion of fine and uniform particles, there is a problem with the durability of the emulsifier, there is no problem in continuous production, and a large amount like the phase inversion emulsification method. Unlike the high temperature and high pressure method and the phase inversion emulsification method, there is no such thing as the emulsification dispersant that deteriorates at high temperature due to high temperature treatment cannot be used without using an emulsification dispersant. A method for producing an aqueous emulsion of a rosin-based substance, which can be emulsified by a combination of a substance and an emulsifying dispersant, has excellent storage stability and mechanical stability, and can be realized with high efficiency, simplicity, and low cost. , An aqueous emulsion composition of the rosin-based substance and a sizing agent for papermaking showing excellent sizing performance using the same.

[Simple explanation of drawings]

[Figure 1]

It is an exploded explanatory view which cut out a part of the schematic diagram of the example of the high shear type rotary emulsification disperser which concerns on this invention.

[Figure 2]

It is a perspective view of the main part of an example of the rotor and the stator.

[Fig. 3]

It is a perspective view of the main part of another example of the rotor and the stator.

[Fig. 4]

It is a process explanatory drawing of one Example of the manufacturing method of this invention.

[Fig. 5]

It is an exploded perspective view which cut out a part of the main part of the high shear type rotary emulsification disperser used in one step.

[Fig. 6]

It is the principle explanatory drawing.

[Explanation of symbols]

1, 31 stator 11, 41 rotor 3 ~ 5, 32 ~ 35 Stator ring 13 ~ 15, 42 ~ 45 Rotor ring 19, 51 slits 20, 50 pores, nozzle 21 Rosin-based substance supply department 22 Emulsifier aqueous solution supply unit 23 High-concentration mixture production process 24 Aqueous emulsion formation process 25 Diluted water supply unit