Abrasive articles and methods for making same

Technical field The invention relates to abrasive articles and methods for their preparation.

Background Art [0002] Abrasive articles, such as coated abrasive articles and associated abrasive articles, have been used in various industries for the machining of objects, such as lapping, abrasion or polishing. Machining, which uses abrasive articles, covers a wide industrial range, from optical industries, automotive paint repair industries to metalworking industries. In each of these examples, abrasives are used in manufacturing equipment to remove bulky material or to affect the surface characteristics of products.

[0003] Surface characteristics include gloss, texture and uniformity. Metal component manufacturers, for example, use abrasive articles on delicate and polished surfaces and often require a uniformly smooth surface. Similarly, optics manufacturers require abrasive articles that produce defect-free surfaces to prevent diffraction and light scattering.

[0004] Manufacturers also require abrasive articles, which in some applications have a high removal rate of the workpiece, but there is often a conflict between removal rate and surface quality. Fine-grain abrasive products typically have smoother surfaces, but have slower removal rates. Lower material removal rates lead to slower production and higher costs.

[0005] Particularly in the context of fine-grain abrasive articles, commercially available abrasives tend to leave random surface defects, such as scratches, which are deeper than the average scratches when removing the workpiece. Such scratches can be caused by grains that break away from the abrasive article, causing rolling dents. If present, these scratches diffuse light, reducing the optical clarity of the lenses or creating a haze or matte finish when working on decorative materials. Such scratches also produce germ points or attachment points that reduce the characteristics associated with release from the surface. Scratches in sanitary facilities, for example, allow bacteria to attach to the surface, and scratches in polished reactors allow bubble formation and act as surface features that initiate unwanted reactions.

[0006] US4457766 discloses an abrasive article comprising abrasive grains and a sizing coating and a working coating. These coatings contain a colloidal composite binder containing silica nanoparticles. The concentration of nanoparticles is below 1% by weight of the binder composition.

[0007] Loss of grain impairs the durability of abrasive articles, leading to frequent replacement. Frequent replacement of abrasive articles is expensive for manufacturers and hence better abrasive articles and methods for making abrasive articles would be desirable.

Features of the Invention [0008] In one particular embodiment, the composition comprises abrasive grain and a binder composition. The binder composition contains from 10% by weight to 90% by weight of the cationically polymerizable compound, but not more than 40% by weight of the cationically polymerizable compound and from 5% to 80% by weight of the particulate filler, based on the weight of the binder composition. The particulate filler contains dispersed submicron solid particles.

[0009] A feature of the invention is also directed to an exemplary abrasive article comprising abrasive grain and a binder comprising a cured composition. The composition contains no more than 90% by weight of a nanocomposite epoxy precursor and contains an acrylic precursor.

[0010] In another exemplary embodiment, the abrasive article comprises abrasive grain and a binder comprising a cured composition. The composition comprises an epoxy precursor and at least 5% by weight of particulate filler, based on the total weight of the composition. The particulate filler has a submicron average particle size.

[0011] In a further exemplary embodiment, the abrasive article comprises abrasive grain and a colloidal composite binder.

[0012] In another exemplary embodiment, the abrasive article comprises abrasive grain and a nanocomposite binder formed in the form of a solution.

[0013] In a further exemplary embodiment, the abrasive article comprises abrasive grain and a composite binder. The composite binder contains a dispersed particulate filler that has an average particle size from 3 nm to 200 nm and a particle size distribution, characterized by a half-width of no more than twice the average particle size.

[0014] In a further exemplary embodiment, the abrasive article comprises a binder that has an Rz efficiency of no more than 3.0 and contains an epoxy acrylate copolymer.

[0015] In another exemplary embodiment, a method of forming an abrasive article includes securing the colloidal composite binder composition and the abrasive grain onto a substrate and curing the colloidal composite binder composition.

[0016] In a further exemplary embodiment, a method of forming an abrasive article includes coating the substrate with an abrasive grain and producing a coating comprising the first binder composition.

[0017] The method of the invention further includes applying a sizing coating to the working coating. The sizing coating comprises a second binder composition comprising a nanocomposite polymer composition. The method also includes curing the working coating and the sizing coating.

[0018] In another exemplary embodiment, a method of forming an abrasive article includes mixing the nanocomposite epoxy precursor and acrylic precursor to form an adhesive composition, applying the adhesive composition to the substrate, applying the abrasive grain to the substrate, and curing the adhesive composition.

Description of the drawings [0019] The present invention may be better understood and its numerous features and advantages will become apparent to those skilled in the art by reference to the accompanying drawings.

Fig. 1 includes an illustration of an example coated abrasive article. Fig. 2 contains an illustration of an exemplary structured abrasive article. Fig. 3 contains an illustration of an example bonded abrasive.

Ways of carrying out the invention [0020] In a particular embodiment of the invention, the abrasive article comprises abrasive grains and a colloidal composite binder. The abrasive article may be a coated abrasive article or associated abrasive article. In one embodiment, the coated abrasive article is a technical or structural abrasive article containing patterned abrasive surface structures.

[0021] The colloidal composite binder generally comprises a polymer matrix and a particulate filler. The colloidal composite binder is formed from a binder composition containing a colloidally suspended particulate filler in the outer phase containing polymeric components such as monomers or polymers. The binder formulation may further comprise catalysts, polymerization initiators, chain transfer agents, reaction inhibitors, plasticizers and dispersing agents.

[0022] In another construction solution, the abrasive article comprises a nanocomposite binder formed in the form of a solution. Nanocomposite binders formed in the form of a solution are formed from nano-composite compositions formed in the form of a solution, which are formed in sol or sol-gel processes and contain a filler in the form of nanoparticles, suspended in the suspension of the polymer component. In a particular embodiment, the particulate filler has an average particle size from 3 nm to 200 nm, such as from 3 nm to 100 nm, and a particle size distribution having a half width not greater than twice the average particle size.

[0023] In particular embodiments, nanocomposite binders and colloidal composite binders have Rz efficacy, as described below, not greater than 3.0. The binder may contain polymeric components selected from the group consisting of epoxy components, acrylate components, oxetane components, and a combination thereof. The polymeric components may be thermosetting or curable by photochemical radiation.

[0024] The composite binders described herein generally contain a particulate filler dispersed in a polymeric matrix. Prior to curing, the composite binder composition is typically a suspension that contains an external phase containing organic polymeric components and optionally solvents. The polymeric component may be a monomer or a polymer in a solvent. The external phase may contain, for example, monomers that polymerize when cured. Alternatively or additionally, the external phase may contain a polymeric material in a solvent. The particulate filler generally forms a dispersed phase in the outer phase.

[0025] The particulate filler may be formed of inorganic particles, such as, for example, metal particles (such as, for example, steel, silver or gold) or a metal complex, such as, for example, metal oxide, metal hydroxide, metal sulfide, halide complex metal, metal carbide, metal phosphate, inorganic salt (such as CaCO3, for example), ceramics or a combination thereof. An example of a metal oxide is ZnO, CdO, SiO2, TiO2, ZrO2, CeO2, SnO2, MoO3, WO3, Al2O3, In2O3, La2O3, Fe2O3, CuO, Ta2O5, Sb2O3, Sb2O5 or a combination thereof. Mixed oxide containing various metals may also be present. Nanoparticles can include, for example, particles selected from the group consisting of ZnO, SiO2, TiO2, ZrO2, SnO2, Al2O3, so-called silica-alumina, and a mixture thereof. Manometric-sized particles can also have an organic component, such as, for example, carbon black, a highly cross-linked polymeric nanoparticle with a core shell, an organically modified nanometer-sized particle, etc. Such fillers are described, for example, in US 6467897 and WO 98/51747.

[0026] Particulate filler formed by solution-based methods, such as sol-formed or sol-gel formed ceramics, are particularly well suited for use in a composite binder. Suitable sols are commercially available. For example, colloidal silicas in aqueous solutions are commercially available under trade names such as "LUDOX" (EI DuPont de Nemours and Co., Inc. Wilmington, Del.), "NYACOL" (Nyacol Co., Ashland, Ma.) And "NALCO" (Nalco Chemical Co., Oak Brook, III.). Many commercially available sols are alkaline and are stabilized by alkali such as sodium hydroxide, potassium hydroxide or ammonium hydroxide. Additional examples of suitable colloidal silicas are described in US Pat. No. 5126394. Silica formed from sol and alumina formed from sol are particularly well suited. Sols may be functionalized by reacting one or more suitable surface treatment agents with inorganic oxide substrate particles in the sol.

[0027] In a particular embodiment, the particulate filler has a submicron size. For example, the particulate filler may be a nano-particulate filler, such as a particulate filler with an average particle size of 3 nm to 500 nm. In an exemplary embodiment, the particulate filler has an average particle size from 3 nm to 200 nm, such as from 3 nm to 100 nm, from 3 nm to 50 nm, from 8 nm to 30 nm, or from 10 nm to 25 nm. In particular embodiments, the average particle size is not greater than 500 nm, such as not greater than 200 nm, less than 100 nm, or not greater than 50 nm. In the case of a particulate filler, the average particle size can be determined as the particle size corresponding to the largest volume fraction on the small angle neutron scattering distribution curve (SANS) or as the particle size corresponding to 0.5 accumulated volume fraction of the SANS distribution curve.

[0028] The particulate filler may also be characterized by a narrow distribution curve that has a half-width of no more than twice the average particle size. The half-width may be, for example, not more than 1.5 or not more than 1.0. The half-width of the distribution is the width of the distribution curve at half its largest height, such as half the fraction of particles at the maximum of the distribution curve. In a particular embodiment, the particle size distribution curve is monomodal. Alternatively, the particle size distribution is bimodal and has more than one maximum in the particle size distribution.

[0029] In a particular embodiment, the binder formulation may contain at least two particulate fillers. Each of the particulate fillers may be formed of a material selected from the materials described above in connection with the particulate filler. Particulate fillers may be of the same material or of different materials. For example, each of the particulate fillers may be formed of silica. In an alternative example, one filler may be formed of silica and the other filler may be formed of alumina. In one example, each of the particulate fillers has an average particle size distribution in which the average particle size is not greater than 1000 nm, such as not greater than 500 nm or less than 100 nm. In another example, one of the particle fillers has a particle size distribution with an average particle size not greater than 1000 nm, such as not larger than 500 nm or less than 100 nm, while the other particle filler has an average particle size greater than 1 micron, such as from 1 micron to 10 microns or from 1 micron to 5 microns. Alternatively, the second particulate filler may have an average particle size of 1500 microns. In a particular embodiment, the binder composition comprising a first particle filler with a submicron average particle size and a second particle filler with an average particle size greater than 1 micron, preferably provides improved mechanical properties when cured to form the binder.

[0030] Typically, the second particulate filler has a low aspect ratio. The second particulate filler may have, for example, an aspect ratio of no more than 2, such as 1 or nearly spherical. The second particulate filler is generally not treated or cured by treatment. In contrast, abrasive grains are typically hardened solids with an aspect ratio of at least 2 and sharp edges.

[0031] When choosing a second particulate filler, settling speed and viscosity are generally taken into account. As the size increases, the fillers in the form of particles larger than 1 micron tend to settle more quickly, however, they exhibit lower viscosity at a higher load, and in addition the refractive index of the particulate filler may be considered. For example, you can choose a filler in the form of particles with a refractive index of at least about 1.35. Further, a particulate filler that does not contain a basic residue can be chosen, since a basic residue can adversely affect the polymerization of cationically polymerizable components.

[0032] The particulate filler is generally dispersed in the external phase. Prior to curing, the particulate filler is colloidally dispersed in the binder suspension and forms a colloidal composite binder after curing. For example, the particulate material may be dispersed, such that Brownian motion maintains the particulate filler in suspension. The particulate material is generally substantially free of clusters of particles. For example, the particulate filler may be substantially monodisperse, such that the particulate filler is dispersed as individual particles, and in specific examples, it has only a slight cluster of particles, if any.

[0033] In a particular embodiment, the particulate filler particles are substantially spherical. Alternatively, the particles have a basic aspect ratio greater than 1, such as at least 2, at least 3 or at least 6, where the basic aspect ratio is the ratio of the longest dimension to the smallest perpendicular dimension to the longest dimension. The particles can also be characterized by a side shape factor defined as the ratio of rectangular dimensions in the plane generally perpendicular to the longest dimension. The particles may be needle-like, such as having a basic aspect ratio of at least 2 and a side aspect ratio of not more than 2, such as 1. Alternatively, the particles may be plate-shaped, such as having an aspect ratio of at least 2, and an aspect ratio of at least 2.

[0034] In an exemplary embodiment, the particulate filler is prepared in an aqueous solution and mixed with the external phase of the suspension. The method of producing such a suspension includes introducing an aqueous solution, such as an aqueous silica solution, polycondensation of silicate, to such a particle size as from 3 nm to 50 nm, adjusting the obtained silica sol to an alkaline reaction, optionally concentrating the sol, mixing the sol with the components of the external liquid phase of the suspension and optionally removing water or other solvent components from the suspension. For example, an aqueous silicate solution, such as an alkali metal silicate solution (e.g., sodium silicate or potassium silicate solution) is added in a concentration ranging from 20% to 50% by weight based on the weight of the solution. The silicate is polycondensed to a particle size of 3 nm to 50 nm, for example by treating the alkali metal silicate solution with an acidic ion exchanger. The obtained silica sol is adjusted to an alkaline reaction (e.g. pH> 8) in order to stabilize against further polycondensation or agglomeration of existing particles. The sol can optionally be concentrated, for example by distillation, typically to a SiO2 concentration of 30 to 40% by weight. The sol is mixed with the components of the external liquid phase, and then water or other solvent components are removed from the suspension. In a particular embodiment, the suspension is substantially anhydrous.

[0035] The proportion of the outer phase in the previously cured binder composition, generally containing organic polymeric components, as a proportion of the binder composition may be from 20% to 95% by weight, for example from 30% to 95% by weight, typically from 50% to 95% by weight, and even more typically from 55% to 80% by weight. The proportion of dispersed particulate filler phase can be from 5% to 80% by weight, for example from 5% to 70% by weight, typically from 5% to 50% by weight, and more typically from 20% to 45% by weight. The colloidally dispersed and submicron particulate fillers described above are particularly useful at a concentration of at least 5% by weight, such as at least 10% by weight, at least 15% by weight, at least 20% by weight or 40% by weight or higher. Unlike traditional fillers, nanocomposites made from solution show low viscosity and better processing characteristics at higher loads. Unless specifically stated otherwise, the amounts of ingredients are expressed as weight% of the component relative to the total weight of the composite binder composition.

[0036] For the preparation of the polymer, the external phase may contain one or more reaction components or polymeric components. The polymeric component may contain monomeric particles, polymeric particles or a combination thereof. The external phase may further comprise components selected from the group consisting of solvents, plasticizers, chain transfer agents, catalysts, stabilizers, dispersing agents, curing agents, reaction mediators and agents for influencing the fluidity of the dispersion.

[0037] Polymeric components can form thermoplastics or thermosets. By way of example, the polymeric components may contain monomers and resins for the formation of polyurethane, polyurea, polymerized epoxide, polyester, polyimide, polysiloxanes (silicones), polymerized alkyl, styrene-butadiene rubber, acrylonitrile, butene-butadiene rubber for the production of thermosetting resins. Another example includes an acrylic or methacrylate polymer component. The polymer precursor components are typically a curable organic material (i.e. a polymer monomer or material capable of polymerizing or crosslinking when exposed to heat or other energy sources such as electron beam, ultraviolet light, visible light, etc., or over time after addition). chemical catalyst, moisture or other agent that causes the polymer to cure or polymerize). An example of a precursor polymeric component includes a reactive component to form an amino-polymer or aminoplast-type polymer, such as an alkylated urea-formaldehyde polymer, melamine-formaldehyde polymer and an alkylated benzoguanine-formaldehyde polymer, an acrylate polymer including acrylate and methacrylate polymer, alkyl acrylate, acrylated epoxy, acrylated urethane, acrylated polyester, acrylated polyester, vinyl ether, acrylated oil or acrylated silicone; an alkyd polymer such as an urethane alkyd polymer; polyester polymer; reactive urethane polymer; a phenolic polymer such as a resol and novolac polymer, a phenol / latex polymer; oxyd polymer; such as a bisphenol-epoxy polymer; isocyanate; isocyanurate; a siloxane polymer comprising an alkylalkoxysilane polymer; or a reactive vinyl polymer. The outer phase of the binder formulation may comprise a monomer, oligomer, polymer or combination thereof. In a particular embodiment, the outer phase of the binder composition contains monomers of at least two types of polymers that can crosslink after curing. The external phase may contain, for example, epoxy components and acrylic components that, when cured, form an epoxy acrylic polymer.

[0038] In an exemplary embodiment, the polymeric reaction components comprise anionically and cationically polymerizable precursors. The external phase may contain, for example, at least one cationically curable component, e.g. at least one cyclic ether component, cyclic lactone component, cyclic acetal component, cyclic thioether, spiro-orthoester component, epoxy functional component or oxetane functional component . The external phase typically contains at least one component selected from the group consisting of epoxy functional components and oxetane functional components. The outer phase may contain, based on the total weight of the composite binder composition, at least 10% by weight of cationically curable components, for example at least 20% by weight, typically at least 40% by weight or at least 50% by weight. The outer phase generally contains, based on the total weight of the composite binder composition, no more than 95% by weight of cationically curable components, for example no more than 90% by weight, no more than 80% by weight or no more than 70% by weight.

[0039] The external phase may comprise at least one epoxy functional component, for example an epoxy functional aromatic component ("aromatic epoxide") or an epoxy functional aliphatic component ("aliphatic epoxy"). The epoxy-functional components are components containing one or more epoxy groups, i.e. one or more three-membered ring structures (oxirans).

[0040] Aromatic epoxy components contain one or more epoxy groups and one or more aromatic rings. The outer phase may contain one or more aromatic epoxy components.

An example of an aromatic epoxy component includes an aromatic epoxy derived from a polyphenol, e.g., bisphenols, such as bisphenol A (4,4'-isopropylidene diol), bisphenol F (bis [4-hydroxyphenyl] methane), bisphenol S (4,4 ' -sulfonyl-diphenol), 4,4'-cyclohexylidene-bisphenol, 4,4'-biphenol or 4,4 '- (9-fluorenylidene) diphenol. The bisphenol may be alkoxylated (e.g. ethoxylated or propoxylated) or halogenated (e.g. brominated). Examples of bisphenolepoxides include bisphenol glycidyl ethers such as bisphenol A or bisphenol F diglycidyl ether.

[0041] A further example of an aromatic epoxide includes triphenylolmethane triglycidyl ether, 1,1,1-tris (p-hydroxyphenyl) ethane triglycidyl ether, or aromatic monophenol-derived epoxides, e.g. resorcinol (e.g. resorcinol diglycidyl ether) or hydroquinone (for example hydroquinone diglycidyl ether). Another example is nonylphenyl glycidyl ether.

[0042] In addition, an example of an aromatic epoxy includes epoxy novolac, for example phenolic epoxy novolac and cresol epoxy novolac. A commercial example of cresol epoxy novolac includes, for example, EPICLON N-660, N-665, N-667, N-670, N-673, N-680, N690 or N-695, manufactured by Dainippon Ink and Chemicals, Inc. An example of a phenolic epoxy novolac includes, for example, EPICLON N-740, N770, N-775 or N-865, manufactured by Dainippon Ink and Chemicals Inc. [0043] In one embodiment, the external phase may contain, based on the total weight of the composite binder composition, at least 10% by weight of one or more aromatic epoxides.

[0044] Aliphatic epoxy components have one or more epoxy groups and are free of aromatic rings. The outer phase may contain one or more aliphatic epoxies. An example of an aliphatic epoxy includes a C2-C30-alkyl glycidyl ether: 1,2-C30-alkyl epoxide, a mono- or multi-glycidyl ether of an aliphatic alcohol or polyol, such as

1,4-butanediol, neopentyl glycol, cyclohexanedimethanol, dibromoneopentyl glycol, trimethylolpropane, poly tetramethylene oxide, polyethylene oxide, polypropylene oxide, glycerin and alkoxylated aliphatic alcohols or polyols.

[0045] In one embodiment, the aliphatic epoxy contains one or more cycloaliphatic ring structures. The aliphatic epoxy may, for example, have one or more cyclohexene oxide structures, for example two cyclohexene oxide structures. An example of an aliphatic epoxide containing a ring structure includes hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F hydrogen diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, bis (4-hydroxycyclohexyl) methyl ether, diglycidyl ether bis (2-hydroxycyclohexyl ether) ) propane, 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl 3,4-epoxy-6-methylcyclohexanecarboxylate, di (3,4-epoxycyclohexylmethyl) butanedicarboxylate, di (3,4-epoxy-6-methylcyclohexylmethyl) butanedicarboxylate, ethylene bis (3,4-epoxycyclohexanecarboxylate), ethanediol di (3,4-epoxycyclohexyl) hexyl ether - (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-1,3-dioxane. An example of an aliphatic epoxy is also given in US Patent No. 6410127.

[0046] In another embodiment, the outer phase comprises, relative to the total weight of the composite binder composition, at least 5% by weight of one or more aliphatic epoxides, for example at least 10% by weight or at least 20% by weight of the aliphatic epoxy. The outer phase generally comprises, based on the total weight of the composite binder composition, not more than 70% by weight of the aliphatic epoxy, for example not more than 50% by weight, not more than 40% by weight.

[0047] The outer phase typically contains one or more mono- or polyglycidyl ethers of aliphatic alcohols, aliphatic polyols, polyester polyols or polyether ether polyols. One example of such a component includes diglycidyl ether

1,4-butanediol, glycidyl ether of polyoxyethylene or polyoxypropylene glycol or triol with molecular weight from 200 to 10,000, glycidyl ether of tetramethylene glycol or random or block copolymers of poly (oxyethylene-oxybutylene). An example of a commercially available glycidyl ether includes a multifunctional glycidyl ether such as Heloxy 48, Heloxy 67, Heloxy 68, Heloxy 107 and Grilonit F713, or monofunctional glycidyl ethers such as Heloxy 71, Heloxy 505, Heloxy 7, Heloxy 8 and Heloxy 61 ( sold by Resolution Performances, <a href="http://www.resins.com/">www.resins.com</a>).

[0048] The outer phase may contain from 3 wt% to 40 wt%, more typically from 5 wt% to 20 wt% of glycidyl mono- or polyethers of an aliphatic alcohol, aliphatic polyol, polyester polyol or polyether polyol.

[0049] The external phase may contain one or more oxetane functional components (oxetanes "). Oxetanes are components that have one or more oxetane groups, i.e. one or more four-membered ring structures containing one oxygen member and three carbon members.

[0050] Examples of oxetanes include ingredients represented by the following formula:

Z-R₂

HjC, CHj O in which

Q1 is a hydrogen atom, an alkyl group having ± 1-6 carbon atoms (such as methyl, ethyl, propyl or butyl), a fluoroalkyl group containing 1-6 carbon atoms, an allyl group, an aryl group, a furyl group or a thienyl group;

Q2 is an alkylene group having 1-6 carbon atoms (such as a methylene, ethylene, propylene or butylene group) or an alkylene group containing an ether bond, for example an oxyalkylene group such as an oxypropylene group or an oxybutylene group;

Z is oxygen or sulfur; and

R2 is a hydrogen atom, an alkyl group containing ą 1-6 carbon atoms (e.g. a methyl group, an ethyl group, a propyl group or a butyl group), an alkenyl group containing 2-6 carbon atoms (e.g. a 1-propenyl group, a 2-propenyl group , a 2-methyl-1-propenyl group, a 2-methyl-2-propenyl group, a 1-butenyl group, a 2-butenyl group or a 3-butyl group), an aryl group containing 6-18 carbon atoms (e.g. phenyl group, naphthyl group, an anthranyl group or phenanthryl group, substituted or unsubstituted arylalkyl group having 7-18 carbon atoms (e.g., benzyl group, fluorobenzyl group, methoxybenzyl group, phenethyl group, styryl group, cinnamyl group, ethoxybenzyl group), e.g. aryloxyalkyl group phenoxymethyl or phenoxyethyl group), an alkylcarbonyl group containing 2-6 carbon atoms (e.g. ethylcarbonyl group, propylcarbonyl group or butylcarbonyl group), alkoxycarbonyl group containing 2-6 carbon atoms (e.g. ethoxycarbonyl group, propoxycarbonyl group or butoxycarbonyl group), Nalkylcarbamoyl group containing 2-6 carbon atoms (e.g. ethylcarbamoyl group, propylcarbamoyl group carbamoyl or pentylcarbamoyl) or a polyether containing 2-1000 carbon atoms. One particularly preferred oxetane is 3-ethyl-3- (2-ethylhexylmethyl) oxetane.

In addition or instead of one or more cationically curable components, the outer phase may contain one or more free radical curable components, e.g. one or more free radical polymerizing components that have one or more ethylenically unsaturated groups, such as e.g. components from ( meth) acrylate (i.e. acrylate or methacrylate) functional groups.

[0052] An example of a monofunctional, ethylenically unsaturated component includes acrylamide, N, N-dimethylacrylamide, (meth) acryloylmorpholine, 7-amino3,7-dimethyl-lookethyl, (meth) acrylate, isobutoxymethyl (meth) acrylamide, isobornyloxyethyl (meth) acrylate, isobornyl meth) acrylate, 2-ethylhexyl (meth) acrylate, ethylene diethylene glycol (meth) acrylate, t-octyl (meth) acrylamide, diacetone (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, lauryl, dicyclopentadiene (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentenyl (meth) acrylate, N, N-dimethyl (meth) acrylamidotetrachlorophenyl (meth) acrylate, 2-tetrachlorophenoxyethyl, (meth) acrylate acrylate tetraacrylate 2-tetrabromo-phenoxyethyl (meth) acrylate, 2-trichlorophenoxyethyl (meth) acrylate, tribromophenyl (meth) acrylate, tribromophenoxy (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, vinylcaprolactam, N-vinyl pyrrolidone, phenoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, pentachlorophenyl (meth) acrylate, pentabromophenyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, (meth) bornyl acrylate, methyltriethylene glycol (meth) acrylate, or a combination thereof.

[0053] Examples of the polyfunctional ethylenically unsaturated component include ethylene glycol di (meth) acrylate, dicyclopentenyl di (meth) acrylate, tri-ethylene glycol diacrylate, tetraethylene glycol di (meth) acrylate, tricyclodecanedildildimethylene tri (meth) acrylate - trimethylolpropane acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, bi-temporal adduct of (meth) acrylic acid and diglycidyl ether of bisphenol A, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, pentaerythritol derivatives from (met ) an acrylate functional group (e.g. pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hex (meth) acrylate, dipentaerythritol penta (meth) acrylate or dipentaerythritol tetra (meth) acrylate), ditrite (meth) acrylate acrylate ethoxylated bisphenol A di (meth) acrylate, propoxylated bisphenol A di (meth) acrylate, ethoxylated, hydrogenated bisphenol A di (meth) acrylate, propoxylated di (meth) acrylate, modified, hydrogenated bisphenol A, ethoxyl di (meth) acrylate - bisphenol F or a combination thereof.

[0054] In one embodiment, the binder formulation comprises one or more components containing at least 3 (meth) acrylate groups, for example 3-6 (meth) acrylate groups or 5-6 (meth) acrylate groups.

[0055] In particular embodiments, the outer phase comprises, based on the total weight of the composite binder composition, at least 3 wt.% Of one or more free radical polymerizing components, for example at least 5 wt.% Or at least 9 wt.%. The outer phase generally contains not more than 50% by weight of free radical polymerizing ingredients, for example not more than 35% by weight, not more than 25% by weight, not more than 20% by weight or not more than 15% by weight. [0056] In general, the components or precursors of the polymeric reaction contain on average at least two functional groups, such as on average at least 2.5 or at least 3.0 functional groups. For example, an epoxy precursor may have 2 or more epoxy functional groups. In another example, the acrylic precursor may have two or more methacrylate functional groups.

[0057] It has been found that the outer phase containing the component which has a polyether backbone has excellent mechanical properties after curing the composite binder composition. An example of a compound that has a polyether backbone includes polytetramethylenediol, glycidyl ether of polytetramethylenediol, polytetramethylenediol acrylate, polytetramethylenediol containing one or more polycarbonate groups or a combination thereof. In one embodiment, the external phase contains from 5% to 20% by weight of the compound having a polyether backbone.

[0058] The external phase may also contain catalysts and initiators. The cationic initiator can catalyze reactions between cationically polymerizable components. The radical initiator can activate free radical polymerization of the radical polymerizing components. The initiator can be activated by means of thermal energy or photochemical radiation. The initiator may contain, for example, a cationic photoinitiator that catalyzes cationic polymerization reactions when exposed to photochemical radiation. In another example, the initiator may be a radical photoinitiator that initiates free radical polymerization reactions when exposed to photochemical radiation. Photochemical radiation includes radiation originating from and not from particulate matter, and includes electron beam radiation and electromagnetic radiation. In a particular embodiment, the electromagnetic radiation comprises radiation that has at least one wavelength in the range from 100 to 700 nm, in particular wavelengths in the ultraviolet range of the electromagnetic spectrum.

[0059] Cationic photoinitiators are generally materials that form active individuals that, when exposed to photochemical radiation, are able to at least partially polymerize epoxides or oxetanes. For example, after exposure to photochemical radiation, a cationic photoinitiator may form cations that can initiate reactions of cationically polymerizable components such as epoxides or oxetanes.

[0060] An example of a cationic photoinitiator includes, for example, onium salt with low nucleophilic anions. An example includes a halon salt, an iodosyl salt or a sulfonium salt, such as is described, for example, in published European patent application EP 153904 and in WO 98/28663, a sulfoxonium salt, such as is described, for example, in published European patent applications EP 35969, 44274, 54509 and 164314, or a diazonium salt such as is described for example in US Patents Nos. 3708296 and 5002856. Other examples of cationic photoinitiators include a metallocene salt such as is described, for example, in published European applications EP 94914 and 94915.

[0061] In exemplary embodiments, the outer phase comprises one or more photoinitiators represented by the following formula (2) or (3):

<img file="PL1855841T3_D0001.tif" />

Q3 represents a hydrogen atom, an alkyl group having 1-18 carbon atoms, or an alkoxy group containing 1-18 carbon atoms;

M is a methane atom, for example antimony;

Z is halogen, e.g. fluoro; at is the number of valence of the metal, for example 5 in the case of antimony.

[0062] In specific examples, the outer phase comprises, relative to the total weight of the composite binder composition, from 0.1% by weight to 15% by weight of one or more cationic photoinitiators, for example from 1% by weight to 10% by weight.

[0063] The onium salt based photoinitiator typically contains an iodonium complex salt or a sulfonium complex salt. Useful aromatic onium complex salts are further described, for example, in US Pat. No. 4256828 (Smith). Exemplary aromatic iodonium complex salt includes diaryliodonium hexafluorophosphate or diaryliodonium hexafluoroanthonate. Exemplary aromatic sulfonium complex salt includes triphenylsulfonium hexafluoroantimonate, phenyl (thiophenyl) diphenylsulfonium hexafluoroantimonate or (thiodi-4,1-phenylene) bis (diphenyl-bis ((OC6-11) hexafluoroantimonate) sulfonium) sulfonate.

[0064] Aromatic onium salts are typically photosensitive only in the ultraviolet spectrum range, and can be sensitized to the near ultraviolet and visible spectrum range by sensitizers for known photolyzed organic halogen compounds. An exemplary sensitizer contains an aromatic amine or a colored aromatic polycyclic hydrocarbon as described, for example, in US Pat. No. 4250053 (Smith).

[0065] Suitable photoactivated, organometallic complex salt includes salts described, for example, in US Pat. No. 5059701 (Keipert), 5191101 (Palazzotto et al.) And 5252694 (Willett et al.). An example of an organometallic complex salt useful as photoactivated initiators

5 +1 - 6 5 includes: (η ⁶-benzene) (n ⁵-cyclopentadienyl) Fe ¹ SbF₆^-, (η ⁶-toluene) (n⁵24 +1 - 6 5 +1 - 6 cyclopentadienyl) Fe ¹ AsF6-^-, (η ⁶-ksylen) (n ⁵-cyclopentadienyl) Fe ¹ SbF 6^-, (η⁶5 +1 - 6 5 kumen) (n⁵-cyklopentadie-phenyl) Fe ¹ PF 6^-, (η-xylenes (mixed isomers)) (n⁵cyclo pentadienylo) Fe +¹ SbF 6^-, (n⁶xylenes (mixed isomers)) (n⁵cyclopentadienyl) Fe +¹ PF 6^-, (n⁶-o-xylene) (n⁵-cyklopentadie-phenyl) Fe +¹ CF3SO₃^-,

5 +1 - 6 5 (η ⁶-m-xylene) (n ⁵-cyclopentadienyl) Fe ¹ BF 4^-, (η ⁶-mezytylen) (n⁵cyclopentadienyl) Fe +¹ SbF 6^-, (η⁶-heksametylobenzen) (η⁵cyclopentadienyl) Fe +¹ SbF5OH^-, (η⁶fluoren) (η⁵-cyclopentadienyl) Fe +¹ SbF 6or their combination.

[0066] Catalysts based on organometallic salts may optionally be accompanied by an accelerator such as a tertiary alcohol oxalate ester. If present, the accelerator is preferably from 0.1% by weight to 4% by weight of the total binder composition.

[0067] A useful, commercially available cationic photoinitiator contains an aromatic sulfonic complex salt, available, for example, under the trade designation "FX-512" from Minnesota Mining and Manufacturing Company, St. Paul, Minn., An aromatic sulfonium complex salt under the trade designation "UV1-6974" available from Dow Chemical Co. or Chivacure 11.

[0068] The outer phase may optionally contain photoinitiators useful in the free radical photocuring of multifunctional acrylates. An example of a free radical photoinitiator includes benzophenone (e.g. benzophenone, alkyl substituted benzophenone or alkoxy substituted benzophenone); benzoin (e.g. benzoin, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether, benzoin phenyl ether and benzoin acetate); acetophenone, such as acetophenone, 2,2-dimethoxyacetophenone, 4- (phenylthio) acetophenone and 1,1-dichloroacetophenone; benzyl ketal such as benzyl dimethyl ketal; anthraquinone such as 2-methyl anthraquinone, 2 ethyl anthraquinone, 2-tert-butyl anthraquinone, 1-chloroanthraquinone and 2-amylanthraquinone; triphenylphosphine; enzooylphosphine oxides, such as, for example, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, thioxantone or xanthone; acridine derivative; derivative of phenazene; quinoxaline derivative; 1-phenyl-1,2-propanedione-2-O-benzoyl oxime; 1-aminophenyl ketone or 1-hydroxyphenyl ketone such as 1-hydroxycyclohexyl phenyl ketone, phenyl- (1-hydroxyisopropyl) ketone and 4-isopropylphenyl- (1-hydroxyisopropyl) ketone; or a triazine compound, for example 4 '' - methylthiophenyl-1-di (trichloromethyl) -3,5, S-triazine, S-triazine-2- (stilbeno) -4,6-bis-trichloromethyl- or parametoxystyryltriazine.

[0069] An exemplary photoinitiator contains benzoin or a derivative thereof, such as α-methylbenzoine, U-phenylbenzoin, α-allylbenzoin, α-benzylbenzoine, benzoin ethers such as benzyldimethyl ketal (available for example under the trade name "IRGACURE 651" from Ciba Specialty Chemicals), benzoin methyl ether, benzoin ethyl ether, benzoin n-butyl ether, acetophenone and its derivative, such as 2-hydroxy-2-methyl-1-phenyl-1-propanone (available for example under the trade designation "DAROCUR 1173" from Ciba Specialty Chemicals) and 1-hydroxycyclohexylphenyl ketone available for example under the trade designation "IRGACURE 184" Ciba Specialty Chemicals), 2-methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone (available for example under the trade designation "IRGACURE 907" from Ciba Specia Chemicals), 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone (available for example under the trade designation "IRGACURE 369" from Ciba Specialty Chemicals) or a mixture thereof.

[0070] Other useful photoinitiators include pivaloethyl ether, anisoquinone ether, anthraquinones such as anthraquinone, 2-ethylanthraquinone, 1-chloroanthraquinone, 1,4-dimethylanthraquinone, 1-methoxyanthraquinone, benzanthraquinone, ethersinium; benzophenone or its derivatives; the iodonium salt or sulfonium salt described above, the complex₅ titanium, such as bis (n⁵-2,4-cyclopentadienyl) bis [2,6-difluoro-3- (1H-pyrrolyl) phenyl) titanium (commercially available under the trade designation "CG1784DC" also from Ciba Specialty Chemicals), halomethyl nitrobenzene such as 4-bromo-methylnitrobenzene e.t.c.; or mono- or bis-acylphosphine (available for example from Ciba Specialty Chemicals under the trade designations "IRGACURE 1700", "IRGACURE 1800", "IRGACURE 1850" and "DAROCUR 4265"). A suitable photoinitiator may contain a mixture of the abovementioned individuals, such as the α-hydroxyketone / acrylic phosphine mixture (available, for example, under the trade designation IRGACURE 2022 from Ciba Specialty Chemicals).

[0071] A further suitable free radical photoinitiator includes an ionic dye-counterion compound which is capable of absorbing photochemical rays and producing free radicals and which can initiate polymerization of acrylates (see, for example, published European patent application 223587 and US Patents No. 4751102, 4772530, 4772541). [0072] The photoinitiator may be included in an amount of not more than 20% by weight, for example not more than 10% by weight and typically not more than 5% by weight based on the total weight of the binder formulation. The photoinitiator may be included, for example, in an amount of from 0.1 wt% to 20.0 wt%, such as from 0.1 wt% to 5.0 wt%, or most typically from 0.1 wt% to 2, 0% by weight, based on the total weight of the binder formulation, although amounts outside these ranges may also be useful. In one example, the photoinitiator is included in an amount of at least 0.1% by weight, such as at least 1.0% by weight, or in an amount of

1.0% by weight to 10.0% by weight.

[0073] The outer phase may optionally contain a thermal curing agent. Such a thermal curing agent is generally thermally stable at temperatures at which the mixing of the components takes place. Exemplary thermal curing agents for epoxy resins and acrylates are well known in the art and are described, for example, in US Pat. No. 6,258,138 (DeVoe et al.). The thermal curing agent can be included in the binder precursor in any effective amount. Such amounts are typically in the range of 0.01 wt.% To 5.0 wt.%, Preferably in the range of 0.025 wt.% To 2.0 wt.%, Based on the weight of the binder formulation, although amounts beyond these may also be useful. ranges.

[0074] The outer phase may also contain other ingredients such as solvents, plasticizers, crosslinkers, chain conveyors, stabilizers, dispersants, curing agents, reaction mediators and agents for influencing the fluidity of the dispersion. The outer phase may also contain, for example, one or more chain conveyors selected from the group consisting of polyol, polyamine, linear or branched glycol polyether, polyester and polylactone.

[0075] In another example, the external phase may contain additional components, such as a hydroxy-functional or amino-functional additive. In general, the specific hydroxyfunctional component does not contain curing groups (such as, for example, acrylate, epoxy or oxetane groups) and are not selected from the group consisting of photoinitiators.

[0076] The external phase may contain one or more hydroxyfunctional components. The hydroxyfunctional ingredients can be helpful in adjusting the mechanical properties of the binder composition after curing. The hydroxyfunctional component contains a monol (hydroxy functional component containing one hydroxyl group) or polyol (hydroxy functional component containing more than one hydroxyl group).

[0077] A representative example of a hydroxy-functional component includes an alkanol, polyalkylene glycol monoalkyl ether, alkylene glycol monoalkyl ether, alkylene glycol and arylalkylene glycol such as 1,2,4-butanetriol, 1,2,6-hexanetriol, 1,2,3- heptanotriol, 2,6-dimethyl-1,2,6hexanetriol, (2R, 3R) - (-) - 2-benzyloxy-1,3,4-butanetriol, 1,2,3-hexane-triol, 1,2, 3-butanetriol, 3-methyl-1,3,5-pentanotriol, 1,2,3-cyclohexanetriol, 1,3,5-cyclohexanetriol, 3,7,11,15-tetramethyl-1,2,3-hexadecanetriol, 2-hydroxymethyltetrahydropyran-3,4,5-triol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 1,3-cyclopentanediol, trans-1,2-cyclooctane diol, 1,16-hexadecanediol, 3,6-dithia-1,8 octanediol, 2-butene-1,4-diol, 1,2- or 1,3-propanediol, 1,2- or 1,4-butanediol,

1,5-pentanediol, 1,6-hexane-diol, 1,7-heptanediol, 1,8-octanediol, 1,9-nananediol, 1-phenyl-1,2-ethanediol, 1,2-cyclohexanediol, 1.5- decaline-diol, 2,5-dimethyl-3-hexine-2,5-diol, 2,2,4-trimethyl-pentane-1,3-diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, 2.7 -dimethyl-3,5-octadiino-2,7-diol, 2,3-butanediol, 1,4-cyclohexanedimethanol, polyoxyethylene or polyoxypropylene glycols or triols with molecular weights from 200 to 10,000, polytetramethylene glycols with variable molecular weight, poly (oxyethylene-oxybutylene) random or block copolymers, copolymers containing attached hydroxyl groups formed by hydrolysis or partial hydrolysis of vinyl acetate copolymers, polyvinylacetal resins containing attached hydroxyl groups with hydroxyl terminal groups, e.g. hydroxyl) or hydroxyfunctional polylactones (for example with hydroxyl terminal groups), aliphatic polycarbonate polyols (e.g. aliphatic polycarbonate diol), hydroxyfunctional polyethers (e.g. with terminal hydroxyl groups), (e.g. polytetrahydrofuran polyols with average number molecular weight in the range 150-4000 g / mol, 150-1500 g / mol or 150-750 g / mol) or a combination thereof. Exemplary polyol further includes an aliphatic polyol such as glycerin, trimethylolpropane, and also a sugar alcohol such as erythritol, xylitol, mannitol or sorbitol. In particular embodiments, the outer phase of the binder formulation contains one or more alicyclic polyols such as 1,4-cyclohexanedimethanol, sucrose, or 4.8 bis (hydroxymethyl) tricyclo (5,2,1,0) decane.

[0078] A suitable outer phase polyether includes, in particular, a linear or branched polyglycol ether obtained by polymerization with a cyclic ether chain opening in the presence of a polyol, for example the above-mentioned polyol, polyglycol ether, polyethylene glycol, polypropylene glycol or tetramethylene glycol or their copolymer.

[0079] Another suitable polyester of the outer phase composition comprises a polyester based on aliphatic, cyclo-aliphatic or aromatic, multifunctional carboxylic acids (e.g. dicarboxylic acids), or specifically all suitable saturated polyesters that are liquid at temperatures from 18^aboutC to 300^aboutC, typically from 18^aboutC to 150^aboutC, typically an amber ester, glutar ester, adipine ester, lemon ester, phthalate ester, isophthalic ester, terephthalic ester or ester of the corresponding hydrogenation products, with an alcohol component composed of monomeric or polymeric polyols, for example the polyols of the aforementioned type.

[0080] Further polyester includes an aliphatic polylactone such as εpolycaprolactone or polycarbonate, which can be obtained, for example, by polycondensation of diol with phosgene. For the external phase, it is typical to use bisphenol A polycarbonate with an average molecular weight of 500 to 100,000.

In order to influence the viscosity of the external phase, and in particular to reduce viscosity or liquefaction, a further suitable auxiliary agent, in particular a solvent, a plasticizer, may be added to the polyol, polyether or saturated polyester or mixtures thereof, where appropriate. thinner, etc. In one embodiment, the compositions may contain, based on the total weight of the binder composition, not more than 15% by weight, such as not more than 10% by weight, not more than 6% by weight, not more than 4% by weight, not more than 2% by weight or 0% by weight of a hydroxyfunctional component. In one example, the binder compositions are free of significant amounts of a hydroxyfunctional component. The lack of significant amounts of hydroxyfunctional components may reduce the hygroscopicity of the binder formulation or articles derived therefrom.

[0082] An example of a hydroxy- or amino-functional organic compound for the production of an alkylene oxide condensation product includes a polyol containing 3-20 carbon atoms, (C8-C18) fatty acid- (C1-C8) alkanol, such as fatty acid-ethanol amides , a fatty alcohol, alkylphenol or a diamine with 2-5 carbon atoms. Such compounds are reacted with alkylene oxide such as ethylene oxide, propylene oxide or mixtures thereof. The reaction can take place in a molar ratio of the organic compound containing a hydroxy or amino group to alkylene oxide, for example 1: 2 to 1:65. The condensation product typically has an average molecular weight of 500 to 10,000, it can be branched, cyclic, linear and can be a homopolymer, copolymer or terpolymer.

[0083] The outer phase may further comprise a dispersant to interact with the surface and modify the surface of the particulate filler. The dispersant may include organosiloxane, functionalized organosiloxane, alkyl substituted pyrrolidone, polyoxyalkylene ether, ethylene oxide-propylene oxide copolymer or a combination thereof. For various particulate fillers, and especially for silica filler, a suitable surface modifier contains siloxane.

[0084] An example of siloxane includes functionalized or non-functionalized siloxane. An example of siloxane includes a compound represented by the formula

RR

B (-! · - &lt;O— | fc-Bi

RX wherein each R is independently substituted or unsubstituted, linear, branched or cyclic C1-10-alkyl, C1-10-alkoxy, substituted or unsubstituted aryl, aryloxy, trifluoro-alkyl, cyanoalkyl or vinyl; wherein B1 or B2 is hydrogen, siloxy, vinyl, silanol, alkoxy, amino, epoxy, hydroxyl, (meth) acrylate, mercapto or solvent repelling groups such as lipophilic or hydrophilic groups (e.g. anionic, cationic), and wherein n is an integer from 1 to 10,000, especially from 1 to 100.

[0085] Functionalized siloxane is generally a compound with a molecular weight of 300 to 20,000. Such compounds are commercially available from, for example, the General Electric Company or Goldschmidt, Inc. A typical functionalized siloxane is an amine functionalized siloxane in which the functional group is typically siloxane terminal.

[0086] Exemplary organosiloxanes are sold under the name Silwet by Witco Corporation. Such rganosiloxanes typically have a weight average molecular weight of 350 to 15,000, end in hydrogen or C 1 -C 4 -alkyl, and may hydrolyze or non-hydrolyze. Typical organosiloxanes include organosiloxanes sold under the names Silwet L-77, L-7602, L-7604 and L-7605, which are polyalkylene oxide modified dialkylpolysiloxanes. [0087] An example of a suitable anionic dispersant includes (C8-C16) -alkylbenzenesulfonate, (C8-C16) -alkanesulfonate, (C8-C18) α-olefin sulfonate, (C8-C16) fatty acid methyl ester, sulfate (C8C16) fatty alcohol, mono- or dialkyl sulfosuccinate, wherein each alkyl is independently (C8-C16) alkyl, alkyl ether sulfate, (C8-C16) carboxylic acid salt or isethionate which has a fatty chain composed of 8 to 18 carbon atoms, for example sodium diethylhexyl sulfosuccinate, sodium methylbenzenesulfonate or sodium bis (2-ethylhexyl) sulfosuccinate (e.g. Aerosol OT or AOT).

[0088] The dispersant is typically a compound selected from organosiloxane, functionalized organo-siloxane, alkyl-substituted pyrrolidone, polyoxyalkylene ether or ethylene oxide-propylene oxide block copolymer.

[0089] An example of a commercial dispersant includes cyclic organosilicon (e.g. SF1204, SF 1256, SF1328, SF1202 (decamethylcyclopentasiloxane (pentamer)), SF1258, SF1528, Dow Corning 245 fluids, Dow Corning 246 fluids, dodecamethylcyclohexasiloxane (heximer) and SF1173; copolymer of polydimethylsiloxane and polyoxyalkylene oxide (e.g. SF 1488 and SF 1288), linear silicone containing oligomers (e.g. Dow Corning 200 (R) fluids); Silwet L-7200, Silwet L-7600, Silwet L-7602, Silwet L-7605, Silwet L-7608 or Silwet L-7622; nonionic surfactants (e.g. Triton X-100, Igepal CO-630, PVP series, Airvol 125, Airvol 305, Airvol 502 and Airvol 205), organic polyester (e.g. Surfynol 420, Surfynol 440 and Surfynol 465) or Solsperse 41000 .

[0090] Another exemplary commercial dispersion agent includes SF1173 (from GE Silicones); organic polyester such as Surfynol 420, Surfynol 440 and Surfynol 465 (from Air Products Inc.); Silwet L-7200, Silvet L-7600, Silwet L7602, Silwey L-7605, Silwet L-7608 or Silwet L-7622 (from Witco) or a non-ionic surfactant such as Tryton X-100 (from Dow Chemicals), Igepal CO-630 (from Rhodia), a series of PVP (from ISP Technologies) and Solsperse 41000 (from Avecia).

[0091] The amount of dispersant is from 0 wt% to 5 wt%. More typically, the amount of dispersant is from 0.1 wt% to 2 wt%. Silanes are typically used in concentrations from 40 mol% to 200 mol%, and especially from 60 mol% to 150 mol%, based on the molar amount of surface active centers on the surface of the filler in the form of nanoparticles. The binder formulation generally contains no more than 5% by weight of dispersant, such as from 0.1% by weight to 5.0% by weight of dispersant based on the total weight of the binder formulation.

[0092] In a particular embodiment, the binder composition contains from 10% by weight to 90% by weight of the cationically polymerizable compound, not more than 40% by weight of the radical polymerizing compound and from 5% to 80% by weight of the particulate filler relative to the total the weight of the binder composition. It is understood that the sum of the amount of ingredients of the binder composition is added to 100% by weight, and as such, when the amounts of one or more ingredients are specified, they correspond to the amount of the other ingredients such that the sum of the amounts is not greater than 100% by weight.

[0093] The cationically polymerizable compound includes, for example, an epoxyfunctional component or an oxetane functional component. The binder formulation may contain, for example, from 10 wt.% To 60 wt.% Cationically polymerizable compound, such as from 20 wt.% To 50 wt.% Cationically polymerizable compound based on the weight of the binder composition. An exemplary binder composition may contain no more than 20% by weight, such as from 5% by weight to 20% by weight, of mono- or poly-glycidyl ethers of aliphatic alcohol, aliphatic polyols, polyester polyol or polyether polyol. An exemplary binder composition may contain no more than 50% by weight, such as from 5% by weight to 50% by weight, of a component that has a polyether backbone, such as polytetramethylenediol, glycidyl ethers of polytetramethylenediol, acrylates of polytetramethylenediol, or polytetramethylene diol containing one or more polyether groups carbonate.

[0094] The free-radical polymerizing compound, for example according to the above example, contains components that have one or more methacrylate groups, such as components that have at least 3 methacrylate groups. In another example, the binder formulation comprises no more than

30% by weight, such as not more than 20% by weight, not more than 10% by weight or not more than 5% by weight of the radical polymerizing compound.

[0095] The composition may further contain no more than 20% by weight of a cationic photoinitiator, such as from 0.1% by weight to 20% by weight of a free radical photoinitiator such as from 0.1% by weight to 20% by weight. The binder composition may contain, for example, no more than 10% by weight, such venom not more than 5% by weight, cationic photoinitiator. In another example, the binder formulation may contain no more than 10% by weight, such as no more than 5% by weight, of the free radical photoinitiator.

[0096] The particulate filler comprises dispersed submicron solid particles. The binder formulation generally contains from 5 wt% to 80 wt%, such as from 5 wt% to 60 wt%, such as from 5 wt% to 50 wt% or from 20 wt% to 45 wt% filler in the form of submicron particles. Particular embodiments contain at least 5% by weight of particulate filler, such as at least 10% by weight or at least 20% by weight. In a particular embodiment, the particulate filler is silica particles formed from a solution and can be colloidally dispersed in a polymer component. The exemplary binder composition may further contain no more than 5% by weight of a dispersant, such as from 0.1% by weight to 5% by weight of a dispersant selected from organosiloxane, functionalized organosiloxane, alkyl-substituted pyrrolidone, polyalkylene ether and ethylene oxide-propylene oxide block copolymer.

In a particular embodiment, the binder formulation is formed by mixing a nanocomposite epoxy or acrylate precursor, i.e. a precursor containing a submicron particle filler. The binder formulation may contain, for example, no more than about 90% by weight of the nanocomposite epoxy, and may contain an acrylic precursor in an amount of not more than 50% by weight of the acrylic precursor. In another example, the nanocomposite acrylic precursor can be mixed with epoxy. [0098] A binder composition comprising an outer phase comprising polymeric or monomeric components and containing a dispersed particulate filler can be used to form a working coating, sizing coating, a flexible coating or a primer coating of a coated abrasive article. In the exemplary method of forming a working coating, the binder composition is coated on a substrate, abrasive grain is applied to the working coating, and the working coating is cured. The sizing coat can be applied to the working coating and abrasive grain. In another exemplary embodiment, the binder composition is mixed with the abrasive grain to form an abrasive slurry that is spread on the substrate and cured. Alternatively, the abrasive slurry is applied to the mold by a method such as injection into the mold and cured to form a bonded abrasive article.

[0099] Abrasive grains may be formed from one or a combination of abrasive grains, including silica, alumina (fused or sintered), zirconia, zirconia / alumina, silicon carbide, garnet, diamond, regular boron nitride, silicon nitride, oxide cerium, titanium dioxide, titanium dioxide, boron carbide, tungsten carbide, iron oxide, chromium oxide, flint and emery. Abrasive grains can be selected, for example, from the group consisting of silica, alumina, zirconia, silicon carbide, silicon nitride, boron nitride, garnet, diamond, co-fused alumina / zirconia, cerium oxide, titanium dioxide, boron carbide, flint, emery, aluminum nitride and their mixture. Specific solutions were developed using dense abrasive grains consisting essentially of alpha alumina.

[0100] The abrasive grain may also have a particular shape. An example of such a shape includes the shape of a rod, triangle, pyramid, cone, full ball, hollow ball, etc. Alternatively, the abrasive grain may be randomly shaped.

[0101] Abrasive grains generally have an average grain size of no more than 2000 microns, such as a size of no more than 1500 microns. In another example, the size of the abrasive grain is not greater than 750 microns, such as the size not greater than 350 microns. The abrasive grain size may be, for example, at least 0.1 microns, such as from 0.1 microns to 1500 microns, and more typically from 0.1 microns to 200 microns or from 1 micron to 100 microns. The abrasive grain size is typically specified according to the largest abrasive grain size. There is usually a distribution of abrasive grain range. Under some conditions, the grain size distribution is strictly regulated.

[0102] In a mixed abrasive slurry comprising the abrasive grain and the binder composition, the abrasive grain comprises from 10 wt% to 90 wt%, such as from 30 wt% to 80 wt% of the weight of the abrasive slurry.

[0103] The abrasive suspension may further include a mill to increase abrasion efficiency and grinding speed. The useful grinder may be based on an inorganic material such as a halogen salt, e.g. sodium cryolite and sodium tetrafluoroborate, or an organic material such as chlorinated wax, e.g. polyvinyl chloride. A particular solution includes cryolite and potassium tetrafluoroborate with a particle size of 1 micron to 80 microns, and most typically 5 microns to 30 microns. The weight percent of the grinder is generally not more than 50% by weight, such as from 0% by weight to 50% by weight, and most typically from 10% by weight to 30% by weight of the total suspension (including abrasive grains).

[0104] After curing to the abrasive article, the binder generally acts in the direction of the abrasive grain being attached to the substrate either in the surface structure or bonded structure. The efficiency of the binder can be determined by forming abrasive articles using changes in the composition of the binder with standard abrasive grains. In a particular example, the binder has an Rz performance not greater than 3.0 as determined in the Rz performance test described below in the Examples section. The binder Rz may be, for example, not greater than 2.75, such as not greater than 2.5 or not greater than 1.5.

[0105] The binder may also exhibit a workpiece removal efficiency of at least 0.7 grams by testing the workpiece removal efficiency, described below in the Examples section. The removal efficiency of the processed material can be, for example, at least 0.9 grams, such as at least 1.0 g or at least 1.1 g.

[0106] In a further example, the binder, after curing, has a Young's modulus of at least 500 MPa, at least 750 MPa. For example, the binder may have a Young's modulus of at least 3100 MPa (450 ksi), at least 4067 MPa (590 ksi), at least 5.61 MPa (815 ksi), at least 5684 MPa (825 ksi) or at least 6132 MPa ( 890 books). The binder may exhibit an elongation at break of at least 1% after curing. For example, the binder may have an elongation at break of at least 1.7%, at least 2.2%, at least 4.0%, at least 9.0%, or at least 11.0%. In a particular example, the binder may have both a Young's modulus of at least 4065 MPa and an elongation at break of at least 9.0%. In another example, the binder may have a Young's modulus of at least 3100 MPa and an elongation at break of at least 11.2%. In a further example, the binder has a Young's modulus of at least 5615 MPa and an elongation at break of at least 4.0%. After curing, the binder may further exhibit a tensile strength of at least 20 MPa, such as at least 30 MPa or at least 40 MPa.

[0107] Fig. 1 illustrates an exemplary embodiment of a coated abrasive article 100 that includes abrasive grain 106 attached to a substrate or support member 102. Abrasive grain 106 is generally attached to substrate 102 by a working coating 104. The working coating 104 includes a binder that is typically formed from a cured composition binder.

[0108] The coated abrasive article 100 may further include a sizing coating 108 lying above the working coating 104 and abrasive grain 106. Sizing coating 108 generally functions to further attach the abrasive grain 106 to substrate 102 and can also provide grinders. Sizing coating 108 is generally formed of a cured binder formulation that may be the same or different from the binder formulation of the working coating.

[0109] The coated abrasive article 100 may optionally include a backing coating 112. The backing coating 112 acts as an antistatic layer, preventing the abrasive grain from sticking to the backing side of the backing 102 and preventing filings from accumulating during sanding. In other examples, the substrate coating 112 may impart additional strength to the substrate 102 and may act to protect the substrate 102 from exposure to the environment. In another example, the undercoat 112 may also act as a flexible layer. The flexible layer may act to relieve stress between the working layer 104 and the substrate 102.

[0110] The substrate 102 may be flexible or rigid. Substrate 102 may be made of any number of different materials, including those conventionally used as substrates for making coated abrasive articles. An exemplary flexible substrate comprises a thin polymeric film (including thin backing films), such as a polyolefin film (e.g., polypropylene, including biaxially oriented polypropylene), polyester film (e.g., polyethylene terephthalate), polyamide film, cellulose ester film, metal foil, mesh, foam (e.g. natural sponge material or polyurethane foam), fabric (e.g. fabric made of fibers or yarns containing polyester, nylon, silk, cotton or rayon), paper, vulcanized paper, vulcanized rubber, vulcanized fiber, nonwoven material or combinations thereof, or treated varieties thereof. The fabric substrate can be woven or knotted by needling. In particular examples, the substrate 102 is selected from the group consisting of paper, polymeric film, fabric, cotton, poly-cotton, rayon, polyester, polinylon, vulcanized rubber, vulcanized fiber, metal foil and a combination thereof. In other examples, the substrate 102 comprises a polypropylene film or a polyethylene terephthalate (PET) film.

[0111] Substrate 102 may optionally have at least one impregnating agent, a front adhesive layer, or a rear adhesive layer. The purpose of these layers is typically to seal the backing 102 or to protect the yarn or fibers in the backing 102. If the backing 102 is a fabric material, at least one of these layers is typically used. The addition of a front adhesive or a back adhesive may result in a "smoother" surface on the front or back of the substrate. Other optional layers known in the art may also be used (e.g., tie coat, see, e.g., US Pat. No. 5700302 (Stoetzel et al.).

[0112] Antistatic material may also be incorporated into the fabric treatment materials. The addition of antistatic material may reduce the tendency of the coated abrasive article to accumulate static electricity when sandblasting wood or wood-like materials. Additional details about anti-static substrates and substrate treatment can be found, for example, in US Pat. No. 5108463 (Buchanan et al.), 5137542 (Buchanan et al.), 5328716 (Buchanan et al.) And 5560753 (Buchanan et al.).

[0113] The substrate 102 may be a fibrous, reinforced thermoplastic such as described, for example, in US Pat. No. 5417726 (Stout et al.) Or with a round tape without weaves, as described, for example, in US Pat. No. 5573619 (Benedict et al.). Similarly, substrate 102 may be a polymeric substrate that has latch pins projecting therefrom, such as described, for example, in US Pat. No. 5505747 (Chesley et al.). Similarly, the backing 102 may be a loop fabric such as described, for example, in US Pat. No. 5565011 (Follett et al.).

[0114] In another example, a pressure sensitive adhesive is introduced on the back side of the coated abrasive article, such that the resulting coated abrasive article can be attached to a soft pad. Exemplary pressure sensitive adhesive includes latex crepe, rosin, acrylic polymer or copolymer, including acrylate polyester (e.g., butyl polyacrylate), vinyl ether (e.g., vinyl n-butyl polyether), alkyd adhesive, rubber adhesive (e.g., natural rubber, rubber) synthetic and chlorinated rubber) or a mixture thereof.

[0115] Exemplary rigid substrate includes a metal plate, ceramic plate, etc. Another example of a suitable rigid substrate is described, for example, in

US Pat. No. 5417726 (Stout et al.).

[0116] Coated abrasive articles, such as coated abrasive article 100 in Fig. 1, can be formed by coating the substrate with an adhesive composition or abrasive suspension. The substrate may optionally be coated with a flexible coating or a base coating prior to coating with the working coating. The binder composition is typically applied to the substrate to form a working coating. In one embodiment, the abrasive grain is applied to the binder composition, wherein the abrasive grain is mixed with the binder composition to form an abrasive slurry prior to application to the substrate. Alternatively, the binder composition is applied to the substrate to form a working coating, and the abrasive grain is applied to the working coating by electrostatic and pneumatic methods. The binder composition is cured by thermal methods or by exposure to photochemical radiation.

[0117] Optionally, the sizing coating is applied to the working coating and the abrasive grain. The sizing coat can be applied before the working coating cures, the working coating and the sizing coating curing simultaneously. Alternatively, the working coating is cured prior to application of the sizing coating, and the sizing coating cured separately.

[0118] The binder formulation forming the working coating, sizing coating, compliant coating, or substrate coating may be a colloidal binder composition. The colloid binder composition contains a submicron particle filler, such as a nanoparticle filler, which has a narrow particle size distribution. In a particular embodiment, the colloidal binder composition is cured to form a sizing coating. In another embodiment, the colloidal binder composition is cured to form a working coating. Alternatively, the colloidal binder composition may be cured to form an optional susceptible coating or optional substrate coating. [0119] In particular embodiments, the abrasive coatings and grains can be patterned to form certain structures. The working coating can, for example, be laid in a pattern to form surface structures that increase the efficiency of the abrasive article. Patterns can be extruded or rolled into coatings using, for example, a rotogravure apparatus to form a structured or technically modified abrasive article.

[0120] An exemplary embodiment of a technically modified or structured abrasive article is shown in Fig. 2. Structured abrasive articles are coated abrasive articles comprising shaped structures embedded in a substrate. Exemplary structured abrasive articles are disclosed in US Patent No. 6,293,980. The structured abrasive article comprises a backing 202 and a layer 204 containing abrasive grains. The substrate 202 may be formed of the materials described above in connection with the substrate 102 in Fig. 1. Layer 204 is generally patterned and has surface structures 206.

[0121] Layer 204 may be formed in the form of one or more coatings. Layer 204 may include, for example, a working coating and optionally a sizing coating. Layer 204 generally includes abrasive grains and a binder. In one example embodiment, the abrasive grain is mixed with the binder composition to form an abrasive slurry. Alternatively, abrasive grains are applied to the binder after coating the binder on substrate 202. Optionally, functional powder may be applied to layer 204 to prevent the layer 204 from sticking to the patterning tools.

[0122] The working layer binder or sizing binder may be a colloid binder in which the composition that cures to form the binder is a colloidal suspension containing a particulate filler. Alternatively or additionally, the binder is a nano-composite binder containing submicron particle filler.

[0123] The structured abrasive article 200 may optionally include a flexible coating and a substrate coating (not shown). These coatings can work as described above.

[0124] In a further example, colloid binder compositions can be used to form bonded abrasive articles, such as abrasive article 300 shown in Fig. 3. In a particular embodiment, the colloid binder composition and abrasive grains are mixed to form an abrasive slurry. The abrasive suspension is applied to the mold and cured colloid binder composition. The resulting abrasive article, such as article 300, contains abrasive grain bonded with a nanocomposite binder into the desired shape.

[0125] In a particular embodiment, the abrasive article is formed by mixing nanocomposite precursors with other polymer precursors and components. A nanocomposite epoxy precursor containing nanoparticle filler and epoxy precursors is mixed with acrylic precursors to form a nanocomposite binder composition. The binder composition is applied to a primer, such as a substrate, or to a mold. Abrasive is applied to the substrate and cured with the binder composition.

[0126] When the nanocomposite binder forms a working coating of the coated abrasive article, the nanocomposite binder composition can be applied to the substrate and the abrasive grains applied to the composition. Alternatively, the binder composition can be applied to the abrasive grain to form a sizing coating. In another example, the binder composition and abrasive grain can be mixed and applied simultaneously to form a working coating on the substrate or filled into a mold. The binder formulation may generally be cured using thermal energy or photochemical radiation, such as ultraviolet radiation.

[0127] Particularly preferred are the solutions of the above-described binder composition, binder, abrasive articles and methods for their preparation. Abrasive articles formed, for example, from the binder compositions described above may exhibit low abrasive grain loss, resulting in better surface quality. For example, when fine abrasive grains are used, such as abrasive grains no larger than 200 microns, the optical quality of the lenses and the glossy finish on metal objects are better. In addition, some solutions improve the life of abrasive articles, which leads to a reduction in the costs of the abrasion and polishing stages, and thus to a reduction in product costs.

EXAMPLES [0128] Binder efficiency is determined by testing the binder composition in a standard abrasive article configuration. In a particular test, the binder composition is used as a sizing coating on the abrasive grain and the working coating. The abrasive grain is 80 micron semi-fragile, heat treated Treibacher grit alumina (BFRPL) P180, and the working coating is made of UV-cured acrylate. The abrasive grains and the working coating lie on a polyester substrate.

[0129] An abrasive belt measuring 1 inch by 30 inches is placed in the micro-finishing test apparatus. A 1.983 inch diameter workpiece ring made of 1045 steel is introduced into the machine. During the test, the workpiece rotates around its central axis in both directions and also oscillates back and forth along the central axis. Mineral sealing oil is applied to the workpiece as a coolant. The back support of the abrasive belt is provided by a shoe made of segmented Indian stone supplied by IMPCO. The microfinisher settings include the drive motor key set to 1.25, the speed set to 14, the vibration motor key set to 2.5, and the pressure set to 75 psi. These conditions provide a cycle time of approximately 5 seconds at 210 rpm and 5 Hz vibration.

[0130] Before testing, rings from the workpiece are pre-conditioned using a 100 micron (Q151) film, then washed with a non-abrasive cleaner and air dried. An initial measurement of the annulus and annular surface is made. The weight of the ring is measured using a Toledo PB 303 scale. Surface quality is measured using a Taylor-Hobson Surtronic 3+ instrument. The rings are mounted in the machine and an abrasive tape is placed. The rings are ground for 5 seconds in each direction, and then washed and measured.

[0131] The effectiveness of Rz binder and the removal efficiency of the workpiece are determined using Rz of the annular surface and material removed from the ring. Rz is the average maximum surface height. The effectiveness of Rz is a measure of the effect of the binder composition on the workpiece Rz measurements. The material removal efficiency is a measure of the effect of the binder composition on the material removal rate. Alternatively, material removal may be indicated by reducing the diameter of the ring.

EXAMPLE 1 [0132] The example illustrates the effect of loading particulate filler on binder efficiency such as Rz efficiency and material removal efficiency. Sizing coatings on a sample of abrasive articles are formed from binder compositions containing Nanopox XP 22/0314 available from Hanse Chemie, an epoxy resin containing 3,4-epoxycyclohexyl carboxylate 3,4-epoxycyclohexyl carboxylate, and 40% by weight colloidal silica particle filler. The binder compositions also contain UVR 6105, which contains 3,4-epoxycyclohexyl methyl-3,4-epoxycyclohexyl carboxylate and does not contain any particulate filler. The binder compositions further comprise a polyol (4.8 bis (hydroxymethyl) tri-cyclo (5.2.1.0) decane), a cationic photoinitiator (Chivacure 1176), a radical photoinitiator (Irgacure 2022 available from Ciba®) and an acrylate precursor (SR 399, dipentaerythritol pentaacrylate available from Atofina-Sartomer, Exton, PA). Table 1 illustrates the concentration of ingredients in the binder compositions and the Rz efficiency achieved and the material removal efficiency.

Table 1

<td>Ingredient</td><td> 1.1</td><td> 1.2</td><td> 1.3</td><td> 1.4</td><td> 1.5</td>

<td></td><td>wt%</td><td>wt%</td><td>wt%</td><td>wt%</td><td>wt%</td>

<td>Nanopox XP 22/0314</td><td> 0,00</td><td> 20,00</td><td> 40,00</td><td> 60,00</td><td> 79,92</td>

<td>UVR 6105</td><td> 79,92</td><td> 59,92</td><td> 39,92</td><td> 19,92</td><td> 0,00</td>

<td>4,8-bis (hydroxymethyl) tricyclo (5.2.1.0) decane</td><td> 13,50</td><td> 13,50</td><td> 13,50</td><td> 13,50</td><td> 13,50</td>

<td>Irgacure 2022</td><td> 0,48</td><td> 0,48</td><td> 0,48</td><td> 0,48</td><td> 0,48</td>

<td>Chivacure 1176</td><td> 1,50</td><td> 1,50</td><td> 1,50</td><td> 1,50</td><td> 1,50</td>

<td>SR 399</td><td> 4,60</td><td> 4,60</td><td> 4,60</td><td> 4,60</td><td> 4,60</td>

<td>Results</td><td></td><td></td><td></td><td></td><td></td>

<td>Filler,%</td><td> 0,00</td><td> 8,00</td><td> 16,00</td><td> 24,00</td><td> 31,97</td>

<td>Effectiveness of</td><td> 3,33</td><td> 3,53</td><td> 2,95</td><td> 3,47</td><td> 3,88</td>

<td>Workpiece removal efficiency material (g)</td><td> 0,96</td><td> 1,01</td><td> 1,14</td><td> 0,90</td><td> 0,89</td>

[0133] As shown in this example, the Rz performance reaches a minimum of 2.95, and the machining removal efficiency reaches a maximum of 1.14 with sample 1.3 containing 16.00 wt% of the particulate filler.

EXAMPLE 2 [0134] In another example, the effect of polyol individuals on Rz efficiency, material removal efficiency, glass transition temperature (Tg) and modulus of elasticity is measured. The adhesive compositions forming the coating sizing samples of abrasive articles contain one polyol selected from the group consisting of Terathane 250, Terathane 1000, 4,8-bis (hydroxymethyl) tricyclo (5.2.1.0) decane, 2-ethyl-1,3-hexanediol and 1.5 -pentanodiol. The selected polyol is mixed with Nanopox XP 22/0314, Irgacure 2022, Chivacure 1176 and Nanocryl XP 21/0940. Nanocryl XP 21/0940 is an acrylate precursor (tetraacrylate) containing 50% by weight filler in the form of colloidal silica particles, available from Hanse Chemie, Berlin. Concentrations and results are shown in Table 2.

TABLE 2

<td>Ingredient</td><td>2.1 wt%</td><td>2.2 wt%</td><td>2.3 wt%</td><td>2.4 wt%</td><td>2.5 wt%</td>

<td>Nanopox XP 22/0314</td><td> 74,46</td><td> 74,46</td><td> 74,46</td><td> 74,46</td><td> 74,46</td>

<td>Irgacure 2022</td><td> 0,48</td><td> 0,48</td><td> 0,48</td><td> 0,48</td><td> 0,48</td>

<td>Chivacure 1176</td><td> 1,50</td><td> 1,50</td><td> 1,50</td><td> 1,50</td><td> 1,50</td>

<td>Nanocryl XP 21/0940</td><td> 11,06</td><td> 11,06</td><td> 11,06</td><td> 11,06</td><td> 11,06</td>

<td>Terathane 250</td><td> 12,49</td><td></td><td></td><td></td><td></td>

<td>Terathane 1000</td><td></td><td> 12,49</td><td></td><td></td><td></td>

<td>4,8-bis (hydroxymethyl) tricyclo (5.2.1.0) decane</td><td></td><td></td><td> 12,49</td><td></td><td></td>

<td>2-ethyl-1,3-hexanediol</td><td></td><td></td><td></td><td> 12,49</td><td></td>

<td>1,5-pentanediol</td><td></td><td></td><td></td><td></td><td> 12,49</td>

<td>Results</td><td></td><td></td><td></td><td></td><td></td>

<td>Filler,%</td><td> 35,32</td><td> 35,32</td><td> 35,32</td><td> 35,32</td><td> 35,32</td>

<td>Effectiveness of</td><td> 2,48</td><td> 3,68</td><td> 3,13</td><td> 2,15</td><td> 1,43</td>

<td>Workpiece removal efficiency material (g)</td><td> 0,52</td><td> 0,67</td><td> 1,00</td><td> 0,56</td><td> 0,25</td>

<td>Tg (delta tangent)</td><td> 84,25</td><td> 16,55</td><td> 139,8</td><td> 93,6</td><td> 53,85</td>

<td>E 'in 23^aboutC (MPa)</td><td> 2374,5</td><td> 2591,5</td><td> 3258</td><td> 2819,5</td><td> 1992</td>

[0135] Trial 2.5 containing 1.5-pentanediol gives the lowest effectiveness of Rz 1.43, but has low removal efficiency of the workpiece. The best removal efficiency of the processed material 1.00 g was found for sample 2.3 formed from 4,8-bis (hydroxymethyl) tricyclo (5.2.1.0) decane. Sample 2.3 also has the highest modulus of elasticity 3258 MPa and the highest Tg 139.8 of all samples in this example.

EXAMPLE 3 [0136] In this example, the effect of the types of acrylate monomer on Rz efficiency and material removal efficiency is examined. Three acrylate resins (Nanocryl XP 21/0940 (tetraacrylate), Nanocryl XP 21/0930 (diacrylate) and Nanocryl 21/0954 (trimethololpropane ethoxytriacrylate) were tested, each containing 50% by weight colloidal silica filler available from Hanse Chemie). The binder coating compositions further include Nanopox XP 22/0314, 1,5-pentadiol, Irgacure 2022 and Chivacure 1176. The compositions and results are shown in the Table

3.

TABLE 3

<td>Ingredient</td><td>3.4 wt%</td><td>3.5 wt%</td><td>3.6 wt%</td>

<td>Nanopox XP 22/0314</td><td> 77,28</td><td> 77,28</td><td> 77,28</td>

<td>1,5-pentanediol</td><td> 15,46</td><td> 15,46</td><td> 15,46</td>

<td>Irgacure 2022</td><td> 0,52</td><td> 0,52</td><td> 0,52</td>

<td>Chivacure 1176</td><td> 1,50</td><td> 1,50</td><td> 1,50</td>

<td>Nanocryl XP 21/0940</td><td> 5,15</td><td></td><td></td>

<td>Nanocryl XP 21/0930</td><td></td><td> 5,15</td><td></td>

<td>Nanocryl XP 21/0954</td><td></td><td></td><td> 5,15</td>

<td>Results</td><td></td><td></td><td></td>

<td>Filler,%</td><td> 33,49</td><td> 33,49</td><td> 33,49</td>

<td>Effectiveness of</td><td> 4,02</td><td> 5,70</td><td> 6,60</td>

<td>Efficiency removes</td><td> 0,45</td><td> 0,46</td><td> 0,37</td>

<td>workpiece</td><td></td><td></td><td></td>

<td>material</td><td></td><td></td><td></td>

[0137] Test 3.4 containing Nanocryl XP / 0940 shows the lowest Rz performance while showing a workpiece removal efficiency comparable to other samples of this example.

EXAMPLE 4 [0138] In this example, the effect of epoxy monomers on Rz effectiveness and removal efficiency of treated material was examined. The concentrations of two epoxy components (Nanopox XP 22/0314 and Nanopox

22/0516 (bisphenol A diglycidyl ether), each available from Hanse

Chemie), having a filler in the form of silica nanoparticles. In addition, the oxetane component OXT-212 (3-ethyl-3- (2-ethylhexyloxymethyl) oxetane) is introduced. Polyol (Terathane 250) and photocatalyst (Chivacure 1176) are also introduced. The compositions and results are shown in Table 4.

TABLE 4

<td>Ingredient</td><td>4.1 wt%</td><td>4.2 wt%</td><td>4.3 wt%</td><td>4.4 wt%</td>

<td>Nanopox XP 22/0314</td><td> 67,89</td><td> 58,19</td><td> 48,50</td><td> 38,80</td>

<td>Nanopox XP 22/0516</td><td> 9,70</td><td> 19,40</td><td> 29,10</td><td> 38,80</td>

<td>Terathane 250</td><td> 9,70</td><td> 9,70</td><td> 9,70</td><td> 9,70</td>

<td>OXT-212</td><td> 9,70</td><td> 9,70</td><td> 9,70</td><td> 9,70</td>

<td>Chivacure 1176</td><td> 2,91</td><td> 2,91</td><td> 2,91</td><td> 2,91</td>

<td>Results</td><td></td><td></td><td></td><td></td>

<td>Filler,%</td><td> 31,04</td><td> 31,04</td><td> 31,04</td><td> 31,04</td>

<td>Effectiveness of</td><td> 2,75</td><td> 2,75</td><td> 2,65</td><td> 2,00</td>

<td>Removal Effectiveness workpiece material (G)</td><td> 0,72</td><td> 0,74</td><td> 0,70</td><td> 0,69</td>

[0139] Sample 4.4 shows the lowest effectiveness of Rz 2.00. Other samples (4.1, 4.2 and 4.3) show comparable effectiveness Rz of 2.65-2.75. Each sample has comparable removal efficiency of the workpiece (0.690,74).

EXAMPLE 5 [0140] In this example, the sample is prepared using a sizing coating that has the binder composition shown in Table 5. The binder composition contains both filler nanoparticles provided by the addition of Nanopox A 610, and micron particle fillers (NP-30 and ATH S-3), which have an approximate average particle size of 3 microns. NP-30 contains spherical silica particles with an average size of about 3 microns. ATH S-3 contains non-spherical aluminum anhydride particles with an average particle size of about 3 microns. The sample has a Young's modulus 8.9 GPa (1300 ksi), tensile strength 77.2 MPa (11.2 ksi) and elongation at break 1%. In addition, an abrasive article that has a sizing coating formed from the composition exhibits Rz 1.75 and 0.0082 mm removal efficiency. Removal of the processed material is indicated by a 0.0082 mm change in diameter of the test ring described above in the experimental method.

TABLE 5

<td>Ingredient</td><td>% by weight</td>

<td>UVR-6105</td><td> 0,71</td>

<td>Heloxy 67</td><td> 6,50</td>

<td>SR-351</td><td> 2,91</td>

<td>DPHA</td><td> 1,80</td>

<td>(3-glycidoxypropyl) trimethoxysilane</td><td> 1,17</td>

<td>Chivacure 184</td><td> 0,78</td>

<td>NP-30</td><td> 46,71</td>

<td>ATH S-3</td><td> 7,78</td>

<td>Nanopox A 610</td><td> 27,75</td>

<td>Chivacure 1176</td><td> 3,89</td>

<td>SDA 5688</td><td> 0,00072</td>

<td>Effectiveness</td><td></td>

<td>Effectiveness of</td><td> 1,75</td>

<td>Workpiece removal material</td><td>0.0082 mm</td>

<td>Young's modulus</td><td>8.9 GPa (1300 books)</td>

<td>Tensile strength</td><td>77.2 MPa (11200 psi)</td>

<td>Elongation</td><td> 1%</td>

[0141] According to a first embodiment, the present invention relates to compositions comprising an abrasive grain and a binder composition, wherein the binder composition comprises from 10% by weight to 90% by weight of a cationically polymerizable compound, not more than 40% by weight of a radically polymerizable compound and 5% by weight up to 80% by weight of the particulate filler, based on the weight of the binder composition, wherein the particulate filler comprises dispersed submicron particles. [0142] According to a preferred embodiment, the present invention relates to a composition further comprising 0.1-20 wt% of a cationic photoinitiator. [0143] According to a further preferred embodiment, the present invention relates to a composition further comprising 0.1-20% by weight of a radical photoinitiator.

[0144] According to a further preferred embodiment, the present invention relates to a composition wherein the abrasive grain has an average size of at least 0.1 micron.

[0145] According to a further preferred embodiment, the present invention relates to a composition in which the abrasive grain is selected from the group consisting of silica, alumina, zirconia, silicon carbide, silicon nitride, boron nitride, garnet, diamond, co-fused alumina / zirconia , cerium oxide, titanium dioxide, boron carbide, flint, emery, aluminum nitride and mixtures thereof.

According to a further preferred embodiment, the present invention relates to a composition wherein the particulate filler has an average particle size from 3 nm to 200 nm.

[0147] According to a more preferred embodiment, the present invention relates to a composition wherein the average particle size of the particulate filler is less than 100 nm.

[0148] According to a most preferred embodiment, the present invention relates to a composition wherein the average particle size of the particulate filler is not more than 50 nm.

[0149] According to a further preferred embodiment, the present invention relates to a composition, wherein the binder composition contains from 5% by weight to

50% by weight particulate filler.

[0150] According to a more preferred embodiment, the present invention relates to a composition wherein the binder composition contains from 20% by weight to 45% by weight of the particulate filler.

[0151] According to a further preferred embodiment, the present invention relates to a composition wherein the binder composition comprises a second particulate filler.

[0152] According to a more preferred embodiment, the present invention relates to a composition wherein the second particulate filler has an average particle size of at least 1 micron.

[0153] According to a most preferred embodiment, the present invention relates to a composition wherein the average particle size of the second particulate filler is from 1 micron to 10 microns.

[0154] According to a further most preferred embodiment, the present invention relates to a composition in which the second particles have an aspect ratio of not more than 2.

[0155] According to a further more preferred embodiment, the present invention relates to a composition wherein the second particulate filler has a refractive index of at least 1.35.

[0156] According to a preferred embodiment, the present invention relates to a composition wherein the cationically polymerizable compound comprises an epoxyfunctional component of the oxetane functional component.

[0157] According to a further preferred embodiment, the present invention relates to a composition wherein the binder composition comprises a glycidyl mono- or polyether aliphatic alcohol, an aliphatic polyol, a polyester polyol or a polyether polyol.

According to a more preferred embodiment, the present invention relates to a composition wherein the binder composition contains from 5 wt% to 20 wt% of a glycidyl mono- or polyether of an aliphatic alcohol, an aliphatic polyol, a polyester polyol or a polyether polyol.

[0159] According to a preferred embodiment, the present invention relates to a composition wherein the radically polymerizable radical contains at least one (meth) acrylate group.

[0160] According to a more preferred embodiment, the present invention relates to a composition wherein the radically polymerizable compound comprises a component which has at least three (meth) acrylate groups.

[0161] According to a preferred embodiment, the present invention relates to a composition further comprising a component which has a polyether skeleton. According to a more preferred embodiment, the present invention relates to a composition wherein the component which has a polyether backbone is selected from the group consisting of polytetramethylenediol diol, polytetramethylene diol glycidyl ether and polytetramethylenediol diacrylate or polytetramethylenediol diol containing a polycarbonate group.

[0163] According to a further more preferred embodiment, the present invention relates to a composition wherein the binder composition contains from 5 wt% to 50 wt%, based on the weight of the composition, of a compound that has a carbon skeleton.

[0164] According to a preferred embodiment, the present invention relates to a composition wherein the binder composition contains a dispersant.

According to a more preferred embodiment, the present invention relates to a composition wherein the dispersant is selected from the group consisting of organosiloxane, functionalized organosiloxane, alkyl substituted pyrrolidone, polyoxyalkylene ether and ethylene oxide / propylene oxide block copolymer. [0166] According to a further more preferred embodiment, the present invention relates to a composition, wherein the binder composition contains from 0.1 wt% to 5 wt% of a dispersant.

[0167] According to a further preferred embodiment, the present invention relates to a process composition in which, after complete curing, the binder composition has an elongation at break of at least 1.0%.

[0168] According to a further preferred embodiment, the present invention relates to a composition wherein, when fully cured, the binder composition has a tensile strength of at least 20 MPa.

[0169] According to a more preferred embodiment, the present invention relates to a composition in which, once fully cured, the binder composition has a tensile strength of at least 30 MPa.

[0170] According to a further preferred embodiment, the present invention relates to a composition in which, when fully cured, the binder composition has a Young's modulus of at least 500 MPa.

[0171] According to a more preferred embodiment, the present invention relates to a composition wherein, when fully cured, the binder composition has a Young's modulus of at least 750 MPa.

[0172] According to a second embodiment, the present invention relates to an abrasive article comprising an abrasive grain and a binder comprising a cured composition, wherein the composition comprises no more than 90% by weight of a nanocomposite epoxy precursor and comprises an acrylic precursor in which the composition contains at least 5.0% by weight of submicron particle filler.

[0173] According to a preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises no more than 50% by weight of an acrylic precursor.

[0174] According to a further preferred embodiment, the present invention relates to an article in which the acrylic precursor comprises a nanocomposite acrylic precursor.

[0175] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises no more than 20% by weight of a polyol.

[0176] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises a photoinitiator.

[0177] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises a thermal initiator. [0178] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises from 5 wt% to 80 wt% filler in the form of submicron particles.

[0179] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the composition contains from 5 wt% to 40 wt% filler in the form of submicron particles.

[0180] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler comprises silica.

[0181] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler is substantially mono-dispersive.

[0182] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler has an average particle size not greater than 100 nm.

[0183] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises a second particulate filler which has an average particle size of at least 1 micron.

[0184] According to a third embodiment, the present invention relates to an abrasive article comprising an abrasive grain and a binder comprising a cured composition, wherein the composition comprises an epoxy precursor and at least 5% by weight of a particulate filler, based on the total weight of the composition, and a particulate filler has a submicron average particle size.

[0185] According to a preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises at least 10% by weight of particulate filler.

[0186] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises at least 20% by weight of particulate filler.

[0187] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the average particle size is not more than 100 nm.

[0188] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the average particle size is not more than 50 nm.

[0189] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the particulate filler has a particle size distribution that has a half width not greater than twice the average particle size.

[0190] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises a second particulate filler which has an average particle size of at least 1 micron.

[0191] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the epoxy precursor comprises a nanocomposite epoxy precursor.

[0192] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises no more than 90% by weight of the epoxy precursor based on the total weight of the composition. [0193] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises no more than 50% by weight of an acrylic precursor.

[0194] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the acrylic precursor comprises a nanocomposite acrylic precursor.

[0195] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises no more than 20% by weight of a polyol.

[0196] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises a photoinitiator.

[0197] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the composition comprises a thermal initiator.

[0198] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the particulate filler comprises silica.

[0199] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the particulate filler is substantially monodisperse.

[0200] According to a fourth embodiment, the present invention relates to an abrasive article comprising an abrasive grain and a colloidal composite binder, wherein the colloidal composite binder comprises at least 5% by weight of submicron particle filler.

[0201] According to a preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder contains from 5 wt% to 80 wt% of a submicron particle filler.

[0202] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder comprises from 5 wt% to 40 wt% of a submicron particle filler. [0203] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder comprises a nanocomposite formed in the form of a solution.

[0204] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder comprises a polymer.

[0205] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an UV curable electromagnetic radiation component.

[0206] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises a thermally curable component.

[0207] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises a cationically polymerizable component.

[0208] According to a most preferred embodiment, the present invention relates to an abrasive article, wherein the cationically polymerizable component has an epoxy functional group.

[0209] According to a further most preferred embodiment, the present invention relates to an abrasive article, wherein the cationically polymerizable component has an oxetane functional group.

[0210] According to a further most preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder comprises a cationic photoinitiator in an amount of from 0.1 wt% to 20 wt%.

According to a further most preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises a radical polymerizing component.

[0212] According to a very most preferred embodiment, the present invention relates to an abrasive article, wherein the free-radical polymerizing component comprises at least one (meth) acrylate group.

[0213] According to a most preferred embodiment, the present invention relates to an abrasive article, wherein the free-radical polymerizing component comprises at least three (meth) acrylate groups.

[0214] According to a further most preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder comprises a radical photoinitiator in an amount of from 0.1 wt% to 20 wt%.

[0215] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an epoxy component. .

[0216] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an acrylic component.

[0217] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an epoxy / acrylic component.

According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder has a Young's modulus of at least 500 MPa.

[0219] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the Young's modulus is at least 4 GPa.

[0220] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder has an elongation at break of at least 1.0%.

[0221] According to a most preferred embodiment, the present invention relates to an abrasive article, wherein the elongation at break is at least 9.0%. [0222] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder has an Rz efficiency of no more than 3.0.

[0223] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder has a work removal efficiency of at least 0.7 g.

[0224] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder comprises a submicron particle filler which has an average particle size from 3 nm to 200 nm.

[0225] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the average particle size is not more than 50 nm.

[0226] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler has a particle size distribution that has a half width not greater than twice the average particle size in the submicron particle filler.

According to a further preferred embodiment, the present invention relates to an abrasive article wherein the submicron particle filler is selected from the group consisting of silica, zirconia, alumina and transition metal oxides.

According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler comprises silica.

[0229] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler is substantially free of clusters.

[0230] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the submicron particle filler is substantially mono-dispersive.

[0231] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive grain has an average particle size of no more than 1500 microns.

[0232] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the average grain size is no more than 750 microns.

According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive grain has an average grain size of at least 0.1 microns.

[0234] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive grain is selected from the group consisting of silica, alumina, zirconia, silicon carbide, silicon nitride, boron nitride, aluminum nitride, co-fused alumina / zirconia , cerium oxide, titanium dioxide, boron carbide, garnet, diamond, flint, emery and mixtures thereof.

[0235] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive article is a coated abrasive article further comprising a substrate on which a colloidal composite binder and abrasive grain is placed.

[0236] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the coated abrasive article is a machined abrasive article, the abrasive grain being arranged in a pattern.

[0237] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the substrate is selected from the group consisting of paper, polymeric film, fabric, cotton, polycotton, rayon, vulcanized rubber, vulcanized fiber, metal foil and a combination thereof. [0238] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder forms a working coating in which or on which the abrasive grain is placed.

[0239] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal composite binder forms a sizing coating formed over the abrasive grain.

[0240] According to a further more preferred embodiment, the present invention relates to an abrasive article, in which the colloidal composite binder forms a flexible layer placed under the layers containing the abrasive grain. [0241] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive article is a bonded abrasive article.

[0242] According to a fifth embodiment, the present invention relates to an abrasive article comprising abrasive grain and a nanocomposite binder formed in the form of a solution.

[0243] According to a preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed in the form of a solution contains from 5 wt% to 80 wt% of the particulate filler. [0244] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed in the form of a solution comprises a polymer.

[0245] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises a component that cures under the action of ultraviolet electromagnetic radiation.

[0246] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an epoxy component. [0247] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an acrylic component.

[0248] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises an epoxy / acrylic component.

[0249] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed in the form of a solution has a Young's modulus of at least 500 MPa.

[0250] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed in solution has an elongation at break of at least 1.0%.

[0251] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed in solution has an Rz efficiency of no more than 3.0.

[0252] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed in solution contains a particulate filler which has an average particle size from 3 nm to about 200 nm.

[0253] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the average particle size is not more than 50 nm.

[0254] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the particulate filler has a particle size distribution that has a half width not greater than twice the average particle size of the particulate filler.

[0255] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the nanocomposite binder formed as a solution comprises a particulate filler which is in colloidal suspension before curing.

[0256] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal suspension is substantially free of clusters.

[0257] According to a most preferred embodiment, the present invention relates to an abrasive article, wherein the colloidal suspension is substantially monodisperse.

[0258] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive grain has an average grain size of no more than 1500 microns.

[0259] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the abrasive article is a coated abrasive article further comprising a substrate on which a nanocomposite solution binder and abrasive grain is placed.

[0260] According to a sixth embodiment, the present invention relates to an abrasive article comprising an abrasive grain and a composite binder containing at least 5% by weight of the dispersed particulate filler, wherein the dispersed particulate filler has an average particle size from 3 nm to 200 nm and a curve a particle size distribution having a half-width of not more than twice the average particle size.

[0261] According to a preferred embodiment, the present invention relates to an abrasive article, wherein the dispersed particulate filler comprises a cured suspension of colloidally dispersed particulate filler.

[0262] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the dispersed particulate filler is substantially free of clusters.

[0263] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the dispersed particulate filler is substantially monodisperse.

[0264] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the binder comprises from 5% by weight to 80% by weight of the dispersed particulate filler.

[0265] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the binder is a nanocomposite formed in the form of a solution.

[0266] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the binder comprises a polymer.

[0267] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the polymer comprises a component that cures under the action of ultraviolet electromagnetic radiation. [0268] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the polymer is selected from the group consisting of epoxy polymer, acrylic polymer and copolymer thereof.

[0269] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the binder has a Young's modulus of at least 500 MPa.

[0270] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the binder has an elongation at break of at least 1.0%.

[0271] According to a seventh embodiment, the present invention relates to an abrasive article comprising a binder that has an Rz efficiency not greater than 3.0, wherein the binder comprises an epoxy / acrylate copolymer.

[0272] According to a preferred embodiment, the present invention relates to an abrasive article, wherein the binder has an effective removal of workpiece material of at least 0.7 g.

[0273] According to a further preferred embodiment, the present invention relates to an abrasive article, wherein the binder comprises a particulate filler which has an average particle size from 3 nm to 200 nm and a particle size distribution that has a half width not greater than twice the average particle size .

[0274] According to a more preferred embodiment, the present invention relates to an abrasive article, wherein the binder comprises from 5 wt% to 80 wt% of a particulate filler.

[0275] According to a further more preferred embodiment, the present invention relates to an abrasive article, wherein the particulate filler is substantially mono-dispersive. According to an eighth embodiment, the present invention relates to a method of forming an abrasive article, the method comprising:

- coating the colloidal composite binder and abrasive grain on the substrate, wherein the colloidal composite binder contains at least 5% by weight of filler in the form of submicron particles, and

- hardening of a colloidal composite binder.

[0276] According to a preferred embodiment, the present invention relates to a method in which the colloidal composite binder is coated in the form of a sizing coating placed on the abrasive grain.

[0277] According to a further preferred embodiment, the present invention relates to a method in which the colloidal composite binder is coated in the form of a working coating in which or on which an abrasive grain is arranged.

[0278] According to a further preferred embodiment, the present invention relates to a method in which the colloidal composite binder is coated in the form of a flexible coating on which layers comprising abrasive grains are arranged.

[0279] According to a further preferred embodiment, the present invention relates to a method in which the coating is carried out by mixing abrasive grain with a colloid composite binder and coating the substrate with a colloid composite binder and abrasive grain.

[0280] According to a further preferred embodiment, the present invention relates to a method in which coating is carried out by first coating a colloidal composite binder on a substrate and then coating the abrasive grain thereon.

[0281] According to a further preferred embodiment, the present invention relates to a method in which the coating of a colloidal composite binder and abrasive grain on a substrate is carried out prior to curing.

[0282] According to a further preferred embodiment, the present invention relates to a method in which the curing of the colloidal composite binder consists in exposing the colloidal composite binder to photochemical radiation.

[0283] According to a further preferred embodiment, the present invention relates to a method, wherein the curing of the colloidal composite binder consists in the thermal curing of the colloidal composite binder.

[0284] According to a ninth embodiment, the present invention relates to a method of forming an abrasive article, the method comprising

- coating the substrate with an abrasive grain and a working coating, the working coating comprising a first binder;

- applying a sizing coating to the working coating, the sizing coating comprising a second binder comprising a nanocomposite polymer and the nanocomposite polymer is formed by mixing the polymer precursor with a sol in the form of nanoparticles; and

- hardening of the working coating and sizing coating.

[0285] According to a preferred embodiment, the present invention relates to a method in which the curing of the working coating and the sizing coating consists in exposing at least one of the working coating or the sizing coating to photochemical radiation.

[0286] According to a further preferred embodiment, the present invention relates to a method in which the curing of the working coating and the sizing coating consists of thermal curing of at least one of the working coating or the sizing coating.

[0287] According to a further preferred embodiment, the present invention relates to a method in which the first binder comprises a second nanocomposite polymer.

[0288] According to a more preferred embodiment, the present invention relates to a method in which the nano-composite polymer comprises ordinary monomer. [0289] According to a further preferred embodiment, the present invention relates to a method further comprising forming a layer susceptible to the substrate under the working layer before coating the substrate with the working layer.

[0290] According to a tenth embodiment, the present invention relates to a method of forming an abrasive article, the method comprising

- mixing the nanocomposite epoxy precursor and acrylic precursor to form a binder, wherein the binder comprises at least 5 wt% filler in the form of submicron particles;

- applying the binder to the primer;

- applying abrasive grain to the primer; and

- binder curing.

[0291] According to a preferred embodiment, the present invention relates to a method in which the undercoat comprises a substrate.

[0292] According to a preferred embodiment, the present invention relates to a method in which the primer is a mold.

[0293] According to a more preferred embodiment, the present invention relates to a method in which the abrasive grain is mixed with the binder and wherein the application of the binder and the application of the abrasive grain comprise applying the binder and abrasive grain together into a mold.

[0294] According to a further preferred embodiment, the present invention relates to a method in which mixing of the nanocomposite epoxy precursor and acrylic precursor consists in mixing no more than 90% by weight of the nanocomposite epoxy precursor relative to the total binder content.

[0295] According to a more preferred embodiment, the present invention relates to a process in which mixing consists in mixing no more than 50% by weight of the acrylic precursor based on the total binder content.

[0296] According to a further more preferred embodiment, the present invention relates to a method in which mixing the nanocomposite epoxy precursor and acrylic precursor further comprises mixing no more than 20% by weight of a polyol with the nanocomposite epoxy precursor and acrylic precursor based on the total binder content.

[0297] According to a further preferred embodiment, the present invention relates to a method in which the acrylic precursor is a nanocomposite acrylic precursor.