KR100927109B1 - How to Form Structured Abrasive Products - Google Patents

Abstract

The present invention relates to a method of forming a structured abrasive product (100). The method of the present invention includes coating the substrate 102 with an abrasive slurry comprising a binder and abrasive particles 104, partially curing the abrasive slurry and forming a pattern in the partially cured abrasive slurry. do.

Abrasive products, binders, abrasive particles, abrasive slurries, partial curing.

Description

Method of forming structured abrasive article

The present invention generally relates to methods and systems for forming structured abrasive articles.

Abrasive products, such as coated abrasives and bonded abrasives, are used in a variety of industries to process workpieces by lapping, grinding, or polishing. Machining using abrasive products covers a wide range of industries, from the optical industry, automotive paint repair industry to the metal fabrication industry. In each of these examples, the manufacturing facility uses abrasives to remove bulk material or to affect the surface properties of the product.

Surface features include gloss, texture, and uniformity. For example, manufacturers of metal parts use abrasive products to make the surface fine and shiny, often requiring a uniformly flat surface. Similarly, optical manufacturers require abrasive products that produce a defect free surface to prevent light diffraction and scattering.

In addition, manufacturers require abrasive products with high stock removal rates for certain applications. However, there is often a tradeoff between removal rate and surface quality. Finer particles of abrasive product typically produce a flatter surface, but have a lower stock removal rate. Lower stock removal rates slower production rates and increase costs.

Particularly with respect to coated abrasive articles, the manufacture of abrasive articles introduces surface structures to improve stock removal rates while maintaining surface quality. Coated abrasive articles (often referred to as processed or structured abrasives) with surface structures or embossed abrasive layer patterns typically have an improved useful life.

However, conventional techniques for forming structured abrasive articles are unreliable and have disadvantages due to performance limitations. Common methods of forming structured abrasive articles include coating a substrate with a viscous binder, coating the viscous binder with a functional powder, and stamping or rolling the structural pattern into the viscous binder. The functional powder prevents the binder from sticking to the patterning tool. The binder is subsequently cured.

Incomplete coating of the viscous binder with the functional powder leads to binder adhesion on the patterning tool. Binder adhesion creates poor structures, leading to poor product performance and product disposal.

The choice of binder suitable for conventional structured abrasive manufacturing techniques is limited to this process. Conventional binders include high charge conventional fillers that increase the viscosity of the binder. Such conventional fillers affect the mechanical properties of the binder. For example, high charge conventional fillers can adversely affect the tensile strength, tensile modulus and elongation at break of the binder. Poor mechanical properties of the binder cause abrasive particles to disappear, leading to scratching and haze on the surface and reducing the life of the abrasive product.

Loss of particles also degrades the performance of the abrasive product, leading to frequent replacement. Frequent replacement of abrasive products incurs costs for manufacturers. Therefore, improved abrasive products and methods of making abrasive products would be desirable.

Description of invention

In certain embodiments, a method of forming a structured abrasive product includes coating a substrate with a binder formulation, partially curing the binder formulation, and forming a pattern in the partially cured binder formulation.

In another aspect, a method of forming a structured abrasive article includes coating a substrate with an abrasive slurry comprising a binder and abrasive particles, partially curing the abrasive slurry and forming a pattern in the partially cured abrasive slurry. Steps.

In a further aspect, the method of forming a structured abrasive product further comprises partially curing the binder formulation to a viscosity index of at least about 1.1, forming a pattern of the structure in the partially cured binder formulation and further partially curing the binder formulation. Curing.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood by reference to the accompanying drawings, which numerous features and advantages thereof will become apparent to those skilled in the art.

1 includes a drawing of an exemplary abrasive article.

2 includes a diagram of an example apparatus for making a structured abrasive article.

In certain embodiments, methods of forming abrasive articles, such as structured abrasive articles, include coating the substrate with a binder formulation, partially curing the binder formulation, and forming a pattern in the partially cured binder formulation. The binder formulation can be introduced into an abrasive slurry comprising the binder formulation and abrasive particles. The slurry can be applied to the coating. In an exemplary embodiment, the binder formulation is partially cured to a viscosity index of at least about 1.1. The method of the present invention may further comprise completely curing the patterned, partially cured binder formulation. In an exemplary embodiment, the binder formulation is formed into a nanocomposite binder formulation.

Processed or structured abrasives generally include a pattern of abrasive structures disposed over a substrate or support. Examples of structured abrasives are described in US Pat. No. 6,293,980, which is incorporated herein by reference in its entirety. Exemplary embodiments of processed or structured abrasives are shown in FIG. 1. The structured abrasive includes a substrate 104 and a layer 104 comprising abrasive particles. In general, layer 104 is patterned to have surface structure 106.

Substrate 102 may be flexible or rigid. Substrate 102 may be made from a number of different materials, including those commonly used as substrates in the manufacture of coated abrasives. Examples of flexible substrates include polymeric films (such as printed films), such as polyolefin films (such as polypropylene including biaxially oriented polypropylene), polyester films (such as polyethylene terephthalate), polyamides Films or cellulose ester films; Metal foil; Mesh; Foams such as natural sponge materials or polyurethane foams; Fabrics such as fabrics made of fibers or yarns including polyester, nylon, silk, cotton, poly-cotton or rayon; paper; Vulcanized paper; Vulcanized rubber; Vulcanized fiber; Nonwoven materials; Combinations thereof; Or treated forms thereof. The fabric substrate can be joined by knitting or stitching. In a particular example, the substrate is selected from the group consisting of paper, polymer film, fabric, cotton, poly-cotton, rayon, polyester, poly-nylon, vulcanized rubber, vulcanized fiber, metal foil, and combinations thereof. In another example, the substrate comprises a polypropylene film or polyethylene terephthalate (PET) film.

Substrate 102 may optionally have one or more of one or more saturating agents, presizing layers, and backsizing layers. The purpose of these layers is typically to seal the substrate or to protect the yarns or fibers in the substrate. If the substrate 102 is a textile material, one or more of these layers are typically used. The addition of the presizing layer or the backsizing layer may further create a "flatter" surface over the front or back side of the substrate 102. Any other layer known in the art may be used (eg, a bonding layer; see US Pat. No. 5,700,302 to Stoetzel et al., Which is incorporated herein by reference in its entirety).

Antistatic materials may be included in the fabric processing material. The addition of an antistatic material can reduce the tendency of the coated abrasive product to accumulate electrostatic electricity when sanding wood or wood like materials. Further discussion of antistatic substrates and substrate treatments can be found, for example, in US Pat. No. 5,108,463 to Buchanan et al .; U.S. Patent No. 5,137,542 to Buchanan et al .; US Pat. No. 5,328,716 to Buchanan; And US Pat. No. 5,560,753 (Buchanan et al.), The entire contents of which are incorporated herein by reference.

Substrate 102 is, for example, infinite as described in fiber reinforced thermoplastics as described in US Pat. No. 5,417,726 (Stout et al.) Or US Patent 5,573,619 (Benedict et al.). Adhesive belts, the entire contents of which are incorporated herein by reference. Likewise, substrate 102 may be a polymeric substrate with protruding hook stems, as described, for example, in US Pat. No. 5,505,747 to Chesley et al., The entire contents of which are incorporated herein by reference. Can be. Similarly, the substrate may be a loop fabric as described, for example, in US Pat. No. 5,565,011 to Follett et al., The entire contents of which are incorporated herein by reference.

In some instances, a pressure sensitive adhesive may be introduced to the back side of the coated abrasive article to secure the resulting coated abrasive article to the pad. Examples of pressure sensitive adhesives include latex crepes, rosins, acrylic polymers or copolymers [including polyacrylate esters such as poly (butyl acrylate)], vinyl ethers such as poly (vinyl n-butyl ether), alkyds Adhesives, rubber adhesives (eg natural rubber, synthetic rubber or chlorinated rubber) or mixtures thereof.

Examples of rigid substrates include metal plates, ceramic plates, and the like. Another example of a suitable rigid substrate is described, for example, in US Pat. No. 5,417,726 to Stout et al., The entire contents of which are incorporated herein by reference.

Layer 104 may be formed of one or more coatings. For example, layer 104 may comprise a make coat and optionally a size coat. Layer 104 generally includes abrasive particles and a binder. In an exemplary embodiment, the abrasive particles are blended with the binder formulation to form an abrasive slurry. Alternatively, after coating the binder formulation to the substrate 102, abrasive particles are applied over the binder formulation. Optionally, functional powder may be applied over layer 104 to prevent layer 104 from sticking to the patterning tool. Alternatively, a pattern can be formed in the layer 104 free of functional powder.

The binder of the primary coating or the secondary coating may be formed of a homopolymer or a blend of polymers. For example, the binder may be formed of an epoxy, an acrylic polymer or a combination thereof. The binder may also include fillers, such as nanoscale fillers or combinations of nanoscale fillers and micron size fillers. In certain embodiments, the binder is a colloidal binder, wherein the formulation that cures to form the binder is a colloidal suspension comprising particulate filler. Alternatively or in addition, the binder may be a nanocomposite binder comprising submicron particulate filler.

Structured abrasive article 100 may optionally include a compliant coating and a substrate coating (not shown). These coatings can function as described above and can be formed into a binder composition.

The binder generally comprises a polymer matrix, which binds the abrasive particles to the backing or cast coating, if present. Typically, the binder is formed into a cured binder formulation. In one exemplary embodiment, the binder formulation comprises a polymer component and a dispersed phase.

The binder formulation may comprise one or more reaction components, or polymer components for preparing the polymer. The polymeric component may comprise monomeric molecules, polymeric molecules or combinations thereof. The binder formulation may further comprise a component selected from the group consisting of solvents, plasticizers, chain transfer agents, catalysts, stabilizers, dispersants, curing agents, reaction mediators and agents which affect the flowability of the dispersion.

The polymeric component may form a thermoplastic or thermoset resin. For example, the polymer component may be polyurethane, polyurea, polymerized epoxy, polyester, polyimide, polysiloxane (silicone), polymerized alkyd, styrene-butadiene rubber, acrylonitrile-butadiene rubber, polybutadiene Monomers and resins, or generally reactive resins for preparing thermosetting polymers, may be included. Still other examples include acrylate or methacrylate polymer components. The precursor polymer component is typically a curable organic material (ie, exposure to heat or other energy sources such as electron beams, ultraviolet light, visible light, etc., or other agents that cure or polymerize chemical catalysts, moisture, or polymers). Polymer monomers or materials capable of polymerization or crosslinking reaction over time upon addition of the polymers). Examples of precursor polymer components include reactive components for forming amino polymers or aminoplast polymers, such as alkylated urea-formaldehyde polymers, melamine-formaldehyde polymers and alkylated benzoguanamine-formaldehyde polymers; Acrylate polymers including acrylate and methacrylate polymers, alkyl acrylates, acrylated epoxy, acrylated urethanes, acrylated polyesters, acrylated polyethers, vinyl ethers, acrylated oils or acrylated silicones; Alkyd polymers such as urethane alkyd polymers; Polyester polymers; Reactive urethane polymers; Phenolic polymers such as resol and novolac polymers; Phenol / latex polymers; Epoxy polymers such as bisphenol epoxy polymers; Isocyanates; Isocyanurate; Polysiloxane polymers including alkylalkoxysilane polymers; Or reactive vinyl polymers. Binder formulations may include monomers, oligomers, polymers or combinations thereof. In certain embodiments, the binder formulation comprises monomers of two or more polymers that can crosslink upon curing. For example, the binder formulation may include an acrylic component and an epoxy component that forms an epoxy / acrylic polymer upon curing.

In an exemplary embodiment, the polymer reaction component comprises anionic and cationic polymerizable precursors. For example, the binder formulation may include one or more cationic curable components, such as one or more cyclic ether components, cyclic lactone components, cyclic acetal components, cyclic thioether components, spiro orthoester components, epoxy functional components Or oxetane functional components. Typically, the binder formulation comprises one or more components selected from the group consisting of an epoxy functional component and an oxetane functional component. The binder formulation may comprise at least about 10% by weight, such as at least about 20% by weight, typically at least about 40% by weight or at least about 50% by weight, based on the total weight of the binder formulation. . In general, the binder formulation comprises up to about 95 weight percent, for example up to about 90 weight percent, up to about 80 weight percent, or up to about 70 weight percent cationic curable component relative to the total weight of the binder formulation. .

The binder formulation may comprise one or more epoxy functional components, such as aromatic epoxy functional components ("aromatic epoxy") or aliphatic epoxy functional components ("aliphatic epoxy"). An epoxy functional component is a component comprising at least one epoxy group, ie at least one three-membered ring structure (oxirane).

Aromatic epoxy compounds include one or more epoxy groups and one or more aromatic groups. The binder formulation may comprise one or more aromatic epoxy components. Examples of aromatic epoxy components include polyphenols such as bisphenols such as bisphenol A (4,4'-isopropylidenediphenol), bisphenol F (bis [4-hydroxyphenyl] methane), bisphenol S Aromatic epoxy derived from (4,4'-sulfonyldiphenol), 4,4'-cyclohexylidenebisphenol, 4,4'-biphenol or 4,4 '-(9-fluorenylidene) diphenol Included. Bisphenols may be alkoxylated (eg ethoxylated or propoxylated) or halogenated (eg brominated). Examples of bisphenol epoxy include bisphenol diglycidyl ethers such as diglycidyl ether of bisphenol A or bisphenol F.

Further examples of aromatic epoxies include triphenylolmethane triglycidyl ether, 1,1,1-tris (p-hydroxyphenyl) ethane triglycidyl ether, or monophenols such as resorcinol (e.g. Aromatic epoxies derived from resorcin diglycidyl ether) or hydroquinone (eg hydroquinone diglycidyl ether). Another example is nonylphenyl glycidyl ether.

Examples of aromatic epoxies also include epoxy novolacs such as phenol epoxy novolacs and cresol epoxy novolacs. Examples of commercially available cresol epoxy novolacs include, for example, EPICLON N-660, N-665, manufactured by Dainippon Ink and Chemicals, Inc. N-667, N-670, N-673, N-680, N-690 or N-695. Examples of phenol epoxy novolacs include, for example, Epiclone N-740, N-770, N-775 or N-865 manufactured by Dainippon Ink and Chemicals Incorporated.

In one embodiment, the binder formulation may contain at least one aromatic epoxy at least 10% by weight relative to the total weight of the binder formulation.

Aliphatic epoxy components have one or more epoxy groups and do not include aromatic rings. The binder formulation may comprise one or more aliphatic epoxy. Examples of aliphatic epoxies include glycidyl ethers of C ₂ -C ₃₀ alkyl; 1,2 epoxy of C ₃ -C ₃₀ alkyl; Aliphatic alcohols or polyols such as 1,4-butanediol, neopentyl glycol, cyclohexane dimethanol, dibromo neopentyl glycol, trimethylol propane, polytetramethylene oxide, polyethylene oxide, polypropylene oxide, glycerol and alkoxy Single or multiple glycidyl ethers of silylated aliphatic alcohols; Or polyols.

In one embodiment, the aliphatic epoxy comprises one or more alicyclic ring structures. For example, aliphatic epoxies may have one or more cyclohexene oxide structures, for example two cyclohexene oxide structures. Examples of aliphatic epoxy containing ring structures include hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, bis (4-hydroxycyclohexyl) methane diglyci Dyl ether, 2,2-bis (4-hydroxycyclohexyl) propane diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6- Methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, di (3,4-epoxycyclohexylmethyl) hexanedioate, di (3,4-epoxy-6-methylcyclohexylmethyl) hexane Dioate, ethylenebis (3,4-epoxycyclohexanecarboxylate), ethanediol di (3,4-epoxycyclohexylmethyl) ether or 2- (3,4-epoxycyclohexyl-5,5-spiro-3 , 4-epoxy) cyclohexane-1,3-dioxane. Examples of aromatic epoxies are also described in US Pat. No. 6,410,127, the entire contents of which are incorporated herein by reference.

In one embodiment, the binder formulation comprises at least about 5 wt%, for example at least about 10 wt% or at least about 20 wt% aliphatic epoxy, relative to the total weight of the binder formulation. Generally, the binder formulation comprises up to about 70% by weight, for example up to about 50% by weight, up to about 40% by weight, based on the total weight of the binder formulation.

Typically, the binder formulation comprises one or more mono or poly glycidyl ethers of aliphatic alcohols, aliphatic polyols, polyesterpolyols or polyetherpolyols. Examples of such components include 1,4-butanediol diglycidyl ether; Glycidyl ethers of polyoxyethylene or polyoxypropylene glycol or triols having a molecular weight of about 200 to about 10,000; Or glycidyl ethers of polytetramethylene glycol or poly (oxyethylene-oxybutylene) random or block copolymers. Examples of commercially available glycidyl ethers include polyfunctional glycidyl ethers such as Heloxi 48, Heloxy 67, Helooxy 68, Helooxy 107 and Grilonit F713; Or monofunctional glycidyl ethers, such as, for example, Heloxi 71, Helo 505, Helo 7, Helo 8 and Helo x 61 (available from Resolution Performance, www.resins.com).

The binder formulation may contain about 3 to about 40 weight percent, more typically about 5 to about 20 weight percent, of mono or poly glycidyl ethers of aliphatic alcohols, aliphatic polyols, polyesterpolyols or polyetherpolyols.

The binder formulation may comprise one or more oxetane functional components (“oxetane”). Oxetane is a component containing one or more oxetane groups, ie, one or more four-membered ring structures comprising one oxygen and three carbon sources.

Examples of oxetane include components of the formula:

In the above formula,

Q ₁ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms (eg, methyl, ethyl, propyl or butyl group), a fluoroalkyl group having 1 to 6 carbon atoms, allyl group, aryl group, furyl group or thienyl group,

Q ₂ is an alkylene group having 1 to 6 carbon atoms (such as methylene, ethylene, propylene or butylene group), or an alkylene group containing an ether bond, such as an oxyalkylene group, such as oxyethylene , Oxypropylene or oxybutylene group,

Z is an oxygen atom or a sulfur atom,

R ₂ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms (eg methyl group, ethyl group, propyl group or butyl group), an alkenyl group having 2 to 6 carbon atoms (eg 1-propenyl group, 2-propenyl) Group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-butenyl group, 2-butenyl group or 3-butenyl group), aryl group having 6 to 18 carbon atoms (e.g. : Phenyl group, naphthyl group, anthranyl group or phenanthryl group), substituted or unsubstituted aralkyl group having 7 to 18 carbon atoms (e.g. benzyl group, fluorobenzyl group, methoxy benzyl group, phenethyl group, Styryl group, cinnamil group, ethoxybenzyl group), aryloxyalkyl group (e.g. phenoxymethyl group or phenoxyethyl group), alkylcarbonyl group with 2 to 6 carbon atoms (e.g. ethylcarbonyl group, propyl Carbonyl group or butylcarbonyl group), alkoxycarbonyl group having 2 to 6 carbon atoms (e.g. ethoxy Carbonyl group, propoxycarbonyl group or butoxycarbonyl group), N-alkylcarbamoyl group having 2 to 6 carbon atoms (e.g. ethyl carbamoyl group, propylcarbamoyl group, butylcarbamoyl group or pentylcarbamoyl group ) Or a polyether group having 2 to 1000 carbon atoms. One particularly useful oxetane is 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane.

In addition to or instead of one or more cationic curable components, the binder formulation may comprise one or more free radical curable components, eg, one or more free radically polymerizable components having one or more ethylenically unsaturated groups, such as (meth) acrylates. (Ie acrylate or methacrylate) functional components.

Examples of monofunctional ethylenically unsaturated components include acrylamide, N, N-dimethylacrylamide, (meth) acryloylmorpholine, 7-amino-3,7-dimethyloctyl (meth) acrylate, isobutoxymethyl (meth Acrylamide, isobornyloxyethyl (meth) acrylate, isobornyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyldiethylene glycol (meth) acrylate, t-octyl (meth) Acrylamide, diacetone (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, lauryl (meth) acrylate, dicyclopentadiene (meth) acrylate, dicyclo Pentenyloxyethyl (meth) acrylate, dicyclopentenyl (meth) acrylate, N, N-dimethyl (meth) acrylamide tetrachlorophenyl (meth) acrylate, 2-tetrachlorophenoxyethyl (meth) acrylic , Tetrahydrofurfuryl (meth) acrylate, tetrabromophenyl (meth) acrylate, 2-tetrabromophenoxyethyl (meth) acrylate, 2-trichlorophenoxyethyl (meth) acrylate, Libromophenyl (meth) acrylate, 2-tribromophenoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, vinyl caprolactam, N-vinylpyrrolidone, phenoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, pentachlorophenyl (meth) acrylate, pentabromophenyl (meth) acrylate, polyethylene glycol mono (meth) Acrylates, polypropylene glycol mono (meth) acrylates, bornyl (meth) acrylates, methyltriethylene diglycol (meth) acrylates or mixtures thereof.

Examples of the polyfunctional ethylenically unsaturated component include ethylene glycol di (meth) acrylate, dicyclopentenyl di (meth) acrylate, triethylene glycol diacrylate, tetraethylene glycol di (meth) acrylate, tricyclodecane Ildimethylene di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth ) Acrylate, neopentyl glycol di (meth) acrylate, bisphenol A diglycidyl ether both ends (meth) acrylic acid adduct, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (Meth) acrylate, polyethylene glycol di (meth) acrylate, (meth) acrylate functional pentaerythritol derivatives (e.g. pentaerythritol Tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate or dipentaerythritol tetra (meth) acrylate) , Ditrimethylolpropane tetra (meth) acrylate, ethoxylated bisphenol A di (meth) acrylate, propoxylated bisphenol A di (meth) acrylate, ethoxylated hydrogenated bisphenol A di (meth) acrylate, propoxylated Modified hydrogenated bisphenol A di (meth) acrylates, ethoxylated bisphenol F di (meth) acrylates or combinations thereof.

In one embodiment, the binder formulation comprises one or more components having three or more (meth) acrylate groups, such as 3 to 6 (meth) acrylate groups or 5 or 6 (meth) acrylate groups do.

In certain embodiments, the binder formulation comprises at least about 3% by weight, for example at least about 5% by weight or at least about 9% by weight, based on the total weight of the binder formulation. Generally, the binder formulation includes up to about 50% by weight, for example up to about 35% by weight, up to about 25% by weight, up to about 20% by weight or up to about 15% by weight of the free radically polymerizable component.

Generally, the polymer reaction component or precursor has an average of at least two functional groups, for example at least 2.5 or at least 3.0 functional groups. For example, the epoxy precursor may have two or more epoxy functional groups. In another embodiment, the acrylic precursor may have two or more methacrylate functional groups.

Surprisingly, binder formulations comprising components with a polyether backbone have been found to exhibit good mechanical properties after curing of the binder formulation. Examples of compounds having a polyether backbone include polytetramethylenediol, glycidyl ethers of polytetramethylenediol, acrylates of polytetramethylenediol, polytetramethylenediol containing one or more polycarbonate groups, or combinations thereof do. In one embodiment, the binder formulation comprises 5-20% by weight of the compound having a polyether backbone.

Binder formulations may also include catalysts and initiators. For example, cationic initiators can catalyze the reaction between cationic polymerizable components. The radical initiator may activate free radical polymerization of the radically polymerizable component. The initiator can be activated by thermal energy or actinic radiation. For example, the initiator may include a cationic photoinitiator that catalyzes the cationic polymerization reaction upon exposure to actinic radiation. In another example, the initiator may include a radical photoinitiator that initiates a free radical polymerization reaction upon exposure to actinic radiation. Actinic radiation includes particulate or nonparticulate radiation and is intended to include electron beam radiation and electromagnetic radiation. In certain embodiments, electromagnetic radiation includes radiation having one or more wavelengths in the range of about 100 to about 700 nm, particularly radiation having a wavelength in the ultraviolet range of the electromagnetic spectrum.

In general, cationic photoinitiators are substances that form active species capable of at least partially polymerizing epoxides or oxetane upon exposure to actinic radiation. For example, cationic photoinitiators can form cations that can initiate a reaction of a cationic polymerizable component such as epoxide or oxetane upon exposure to actinic radiation.

Examples of cationic photoinitiators include, for example, onium salts having a weak nucleophilic anion. Examples thereof include halonium salts, iodosil salts or sulfonium salts, such as those described in European Patent Application EP 153904 and WO 98/28663, for example European Patent Application EP. Sulfoxium salts as described in 35969, EP 44274, EP 54509 and EP 164314, or diazonium salts as described in US Pat. Nos. 3,708,296 and 5,002,856. . The disclosures of all these eight patent applications are incorporated herein by reference in their entirety. Other examples of cationic photoinitiators include, for example, metals such as those described in European Patent Applications EP 94914 and EP 94915, the disclosures of which are incorporated herein by reference in their entirety. Strong salts are included.

In an exemplary embodiment, the binder formulation comprises one or more photoinitiators of Formula 1 or Formula 2 below.

In Formula 1 and Formula 2 above,

Q ₃ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or an alkoxyl group having 1 to 18 carbon atoms,

M is a metal atom, for example antimony,

Z is a halogen atom, for example fluorine,

t is the valence of the metal, for example 5 in the case of antimony.

In certain embodiments, the binder formulation comprises about 0.1 to about 15 weight percent, for example about 1 to about 10 weight percent, of one or more cationic photoinitiators, relative to the total weight of the binder formulation.

Typically, onium salt photoinitiators include iodonium complex salts or sulfonium complex salts. Useful aromatic onium complex salts are described, for example, in US Pat. No. 4,256,828 (Smith), the entire contents of which are incorporated herein by reference. Examples of aromatic iodonium complex salts include diaryliodonium hexafluorophosphate or diaryliodonium hexafluoroantimonate. Examples of aromatic sulfonium complex salts include triphenylsulfonium hexafluoroantimonate p-phenyl (thiophenyl) diphenylsulfonium hexafluoroantimonate or sulfonium (thiodi-4,1-phenylene) bis ( Diphenyl-bis ((OC-6-11) hexafluoroantimonate)).

Aromatic onium salts are typically photosensitive only in the ultraviolet region of the spectrum. However, they may be sensitive to the near ultraviolet and visible ranges by known sensitizers for photodegradable organic halogen compounds. Examples of sensitizers include aromatic amines or colored aromatic polycyclic hydrocarbons as described, for example, in US Pat. No. 4,250,053 (Smith, the entire contents of which are incorporated herein by reference).

Suitable photoactivated organometallic complex salts include, for example, US Pat. No. 5,059,701 to Keipert; 5,191,101 (Palazzotto et al.) And 5,252,694 (Willett et al., The entire contents of which are incorporated herein by reference). Useful examples of organic complex metal salt as a photoactive initiators (c ⁶ - benzene) (c ⁵ - cyclopentadienyl) Fe ⁺¹ SbF ₆ ^-; (c ⁶ - toluene) (c ⁵ - cyclopentadienyl) Fe ⁺¹ AsF ₆ ^-; (c ⁶ - xylene) (c ⁵ - _{^{cyclopentadienyl) Fe +1 SbF 6 -, (}} c 6 - cumene) (c ⁵ - _{^{cyclopentadienyl) Fe +1 PF 6 -, (}} c 6 - xylene ( mixed isomers)) (c ⁵ - _{^{cyclopentadienyl) - Fe +1 SbF 6 -,}} (c 6 - xylene (mixed isomers)) (c ⁵ - cyclopentadienyl) Fe ⁺¹ PF ₆ ^-, ( c ⁶ -o- xylene) (c ⁵ - _{^{cyclopentadienyl) Fe +1 CF 3 SO 3 -}} , (c 6 m- xylene) (c ⁵ - _{^{cyclopentadienyl) Fe +1 BF 4 -, (}} c ^{6-mesitylene)} (c ⁵ - _{^{cyclopentadienyl) Fe +1 SbF 6 -, (}} c 6 - hexamethylbenzene) (c ⁵ - _{^{cyclopentadienyl) Fe +1 SbF 5 OH -,}} (c 6 - Fluorene) (c ⁶ -cyclopentadienyl) Fe ⁺¹ SbF ₆ ^- or a combination thereof.

Optionally, the organometallic salt catalyst can be achieved by an accelerator, for example an oxalate ester of tertiary alcohol. If present, the promoter preferably comprises about 0.1 to about 4 weight percent of the total binder formulation.

Useful cationic photoinitiators commercially available include, for example, aromatic sulfonium complexes sold under the trade name "FX-512" from the Minnesota Mining and Manufacturing Company (St. Paul, Minn.). Salts, aromatic sulfonium complex salts or Chivacure 1176 sold under the trade designation "UVI-6974" from Dow Chemical Co.

The binder formulation may optionally include photoinitiators useful for the photocuring of free radical multifunctional acrylates. Examples of free radical photoinitiators include benzophenones such as benzophenone, alkyl substituted benzophenones or alkoxy substituted benzophenones; Benzoin (eg benzoin, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether, benzoin phenyl ether and benzoin acetate); Acetophenones such as acetophenone, 2,2-dimethoxyacetophenone, 4- (phenylthio) acetophenone and 1,1-dichloroacetophenone; Benzyl ketals such as benzyl dimethyl ketal and benzyl diethyl ketal; Anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-3-butylanthraquinone, 1-chloroanthraquinone and 2-amylanthraquinone; Triphenylphosphine; Benzoylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide; Thioxanthone or xanthone; Acridine derivatives; Phenazene derivatives; Quinoxaline derivatives; 1-phenyl-1,2-propanedione-2-O-benzoyloxime; 1-aminophenyl ketones or 1-hydroxyphenyl ketones such as 1-hydroxycyclohexyl phenyl ketone, phenyl (1-hydroxyisopropyl) ketone and 4-isopropylphenyl (1-hydroxyisopropyl) ) Ketones; Or triazine compounds, for example 4 "'-methyl thiophenyl-1-di (trichloromethyl) -3,5-S-triazine, S-triazine-2- (stilbene) -4,6 Bistrichloromethyl or paramethoxy styryl triazine.

Examples of photoinitiators include benzoin or derivatives thereof such as α-methyl benzoin; U-phenylbenzoin; α-allylbenzoyl; α-benzylbenzoin; Benzoin ethers such as benzyl dimethyl ketal (e.g., sold under the trade name "IRGACURE 651" by Ciba Specialty Chemicals), benzoin methyl ether, benzoin ethyl ether , Benzoin n-butyl ether; Acetophenone or derivatives thereof such as 2-hydroxy-2-methyl-1-phenyl-1-propanone (for example sold under the trade name "DAROCUR 1173" by Ciba Specialty Chemicals) And 1-hydroxycyclohexyl phenyl ketone (eg sold under the trade name “Irgacure 184” from Ciba Specialty Chemicals; 2-methyl-1- [4- (methylthio) phenyl] -2- (4 -Morpholinyl) -1-propanone (for example sold under the trade name "Irgacure 907" by Ciba Specialty Chemicals); 2-benzyl-2- (dimethylamino) -1- [4- (4 -Morpholinyl) phenyl] -1-butanone (for example sold under the trade name "Irgacure 369" by Ciba Specialty Chemicals) or blends thereof.

Other useful photoinitiators include pivaloin ethyl ether, anisoin ethyl ether; Anthraquinones such as anthraquinone, 2-ethylanthraquinone, 1-chloroanthraquinone, 1,4-dimethylanthraquinone, 1-methoxyanthraquinone, benzanthraquinonehalomethyltriazine and the like; Benzophenones or derivatives thereof; Iodonium salts or sulfonium salts as described above; Titanium complexes such as bis (c5-2,4-cyclopentadienyl) bis [2,6-difluoro-3- (1H-pyrrolyl) phenyl) titanium (trade name "CGI784DC" from Ciba Specialty Chemicals) Commercially available); Halomethylnitrobenzene such as 4-bromomethylnitrobenzene and the like; Or mono- or bis-acylphosphines (e.g., sold under the trade names "Irgacure 1700", "Irgacure 1800", "Irgacure 1850" and "Darocure 4265") from Ciba Specialty Chemicals. This includes. Suitable photoinitiators include blends of the compounds described above, such as α-hydroxy ketone / acrylphosphine oxide blends (eg, sold under the trade name “Irgacure 2022” from Ciba Specialty Chemicals).

Further suitable free radical photoinitiators include ionic dye counter ionic compounds, which can absorb actinic radiation and generate free radicals and initiate the polymerization of acrylates. See EP 223587. And US Pat. Nos. 4,751,102, 4,772,530 and 4,772,541, the entire contents of which are incorporated herein by reference.

The photoinitiator can be present in an amount of about 20% by weight or less, such as about 10% by weight or less, typically about 5% by weight or less, based on the total weight of the binder formulation. For example, the photoinitiator may be present in an amount of 0.1 to 20.0 weight percent, such as 0.1 to 5.0 weight percent or most typically 0.1 to 2.0 weight percent, based on the total weight of the binder formulation. Other amounts may also be useful. In one example, the photoinitiator may be present in an amount of about 0.1% or more, for example about 1.0% or more or 1.0% to 10.0% by weight.

Optionally, a thermal curing agent can be included in the binder formulation. Such thermal curing agents are generally thermally stable at the temperatures at which mixing of the components occurs. Examples of thermal curing agents for epoxy resins and acrylates are known in the art and are described, for example, in US Pat. No. 6,258,138 to DeVoe et al., The entire contents of which are incorporated herein by reference. have. The thermal curing agent may be present in an effective amount in the binder precursor. Such amounts are typically in the range of about 0.01 to about 5.0 weight percent, preferably about 0.025 to about 2.0 weight percent, based on the weight of the binder formulation, although amounts outside these ranges may also be useful.

The binder formulation may also include other components such as solvents, plasticizers, crosslinkers, chain transfer agents, stabilizers, dispersants, curing agents, reaction mediators and agents that affect the flowability of the dispersion. For example, the binder formulation may also include one or more chain transfer agents selected from the group consisting of polyols, polyamines, linear or branched polyglycol ethers, polyesters and polylactones.

In another example, the binder formulation may include additional ingredients, such as hydroxy functional or amine functional ingredients and additives. In general, certain hydroxy functional components are free of curable groups (eg, acrylate-, epoxy- or oxetane groups) and are not selected from the group consisting of photoinitiators.

The binder formulation may comprise one or more hydroxy functional components. The hydroxy functional component can help to further adjust the mechanical properties of the binder formulation upon curing. Hydroxy functional components include monools (hydroxy functional components comprising one hydroxy group) or polyols (hydroxy functional components comprising one or more hydroxy groups).

Representative examples of hydroxy functional components include alkanols, monoalkyl ethers of polyoxyalkylene glycols, monoalkyl ethers of alkylene glycols, alkylene and arylalkylene glycols such as 1,2,4-butanetri Ol, 1,2,6-hexanetriol, 1,2,3-heptanetriol, 2,6-dimethyl-1,2,6-hexanetriol, (2R, 3R)-(-)-2- Benzyloxy-1,3,4-butanetriol, 1,2,3-hexanetriol, 1,2,3-butanetriol, 3-methyl-1,3,5-pentanetriol, 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-cyclooctanediol, 1,1,6 Hexadecanediol, 3,6-dithia-1,8-octanediol, 2-butyne-1,4-diol, 1,2- or 1,3-propanediol, 1,2- or 1,4- Butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9- Nandiol, 1-phenyl-1,2-ethanediol, 1,2-cyclohexanediol, 1,5-decalindiol, 2,5-dimethyl-3-hexine-2,5-diol, 2,2,4 -Trimethylpentane-1,3-diol, neopentylglycol, 2-ethyl-1,3-hexanediol, 2,7-dimethyl-3,5-octadiyne-2,7-diol, 2,3-butanediol , 1,4-cyclohexanedimethanol, polyoxyethylene or polyoxypropylene glycol or triol of molecular weight about 200 to about 10,000, polytetramethylene glycol of varying molecular weight, poly (oxyethylene-oxybutylene) random or block air Copolymers, copolymers containing pendant hydroxy groups formed by hydrolysis or partial hydrolysis of vinyl acetate copolymers, polyvinyl acetal resins containing pendant hydroxyl groups, hydroxy functionality (e.g. Monofunctional) polyester or hydroxy functional (eg hydroxy terminated) polylactone, aliphatic Polycarbonate polyols (e.g. aliphatic polycarbonate diols), hydroxy functional (e.g. hydroxy terminated) polyethers (e.g., number average molecular weights range from 150 to 4000 g / mol, 150 to 1500 g / mol or 150 To 750 g / mol polytetrahydrofuran polyol) or combinations thereof. Examples of polyols further include aliphatic polyols such as glycerol, trimethylolpropane or sugar alcohols such as erythritol, xylitol, mannitol or sorbitol. In certain embodiments, the binder formulation may comprise one or more cycloaliphatic polyols, such as 1,4-cyclohexane-dimethanol, sucrose or 4,8-bis (hydroxymethyl) tricyclo (5,2,1,0 It includes decane.

Suitable polyethers for binder formulations include, in particular, polyols such as the aforementioned polyols; Linear or branched polyglycol ethers obtainable by ring-opening polymerization of cyclic ethers in the presence of polyglycol ethers, polyethylene glycols, polypropylene glycols or polytetramethylene glycols or copolymers thereof.

Still other polyesters suitable for binder formulations include polyesters based on polyols and aliphatic, cycloaliphatic or aromatic polyfunctional carboxylic acids (eg dicarboxylic acids), or specifically, 18 to 300 ° C., typically 18 to 150 Esters of all corresponding saturated polyesters, typically succinic acid esters, glutaric acid esters, adipic acid esters, citric acid esters, phthalic acid esters, isophthalic acid esters, terephthalic acid esters or corresponding hydrogenation products which are liquid at temperatures of < RTI ID = 0.0 > , Alcohol component consists of monomeric or polymeric polyols of the kind described above).

Further polyesters include aliphatic polylactones such as α-polycaprolactone or polycarbonates, which can be obtained, for example, by polycondensing diols with phosgene. For binder formulations, it is common to use polycarbonates of bisphenol A having an average molecular weight of 500 to 100,000.

In order to influence the viscosity of the binder formulation, in particular the viscosity reduction or liquefaction, the polyols, polyethers or saturated polyesters or mixtures thereof may optionally be mixed with further suitable auxiliaries, in particular solvents, plasticizers, diluents and the like. . In one embodiment, the composition is about 15% by weight or less, such as about 10% by weight, about 6% by weight, about 4% by weight or less, about 2% by weight or less, relative to the total weight of the binder formulation, or About 0% by weight of a hydroxy functional component. In one example, the binder formulation does not include substantial amounts of hydroxy functional components. The absence of substantial amounts of hydroxy functional components can reduce the hygroscopicity of the binder formulation or product obtained therefrom.

Examples of hydroxy or amine functional organic compounds for producing condensation products with alkylene oxides include (C8-C18) fatty acids (C1-C8) alkanol amides, fatty acids such as polyols having 3 to 20 carbon atoms, fatty acid ethanol amides, and the like. Alcohols, alkylphenols or diamines having 2 to 5 carbon atoms. Such compounds are reacted with alkylene oxides such as ethylene oxide, propylene oxide or mixtures thereof. The reaction may occur, for example, at a molar ratio of 1: 2 to 1:65 of hydroxy or amine containing alkyl compounds to alkylene oxides. Condensation products typically have a weight average molecular weight of about 500 to about 10,000 and can be branched, cyclic, linear and homopolymers, copolymers or terpolymers.

The binder formulation may further comprise a dispersant that reacts with and modifies the surface of the particulate filler. For example, dispersants may include organosiloxanes, functionalized organosiloxanes, alkyl substituted pyrrolidones, polyoxyalkylene ethers, ethylene oxide propylene oxide copolymers or combinations thereof. For various particulate fillers, especially silica fillers, suitable surface modifiers include siloxanes.

의 화합물(여기서, R은 각각 독립적으로 치환되거나 치환되지 않은 선형, 분지형 또는 사이클릭 C_1-10 알킬, C_1-10 알콕시, 치환되거나 치환되지 않은 아릴, 아릴옥시, 트리할로알킬, 시아노알킬 또는 비닐 그룹이고, B₁ 또는 B₂는 수소, 실록시 그룹, 비닐, 실란올, 알콕시, 아민, 에폭시, 하이드록시, (메트)아크릴레이트, 머캅토 또는 용매 기피 그룹, 예를 들면, 친지성 또는 친수성(예: 음이온성, 양이온성) 그룹이며, n은 약 1 내지 약 10,000의 정수, 특히 약 1 내지 약 100의 정수이다)이 포함된다.Examples of siloxanes include functionalized or unfunctionalized siloxanes. Examples of siloxanes include chemical formulas

Where R is each independently substituted or unsubstituted linear, branched or cyclic C _1-10 alkyl, C _1-10 alkoxy, substituted or unsubstituted aryl, aryloxy, trihaloalkyl, cya Noalkyl or vinyl group, B ₁ Or B ₂ is hydrogen, siloxy group, vinyl, silanol, alkoxy, amine, epoxy, hydroxy, (meth) acrylate, mercapto or solvent avoiding group, for example lipophilic or hydrophilic (eg anionic) Cationic), and n is an integer from about 1 to about 10,000, in particular from about 1 to about 100).

In general, the functionalized siloxanes are compounds having a molecular weight range of about 300 to about 20,000. Such compounds are commercially available, for example, from General Electric Company or Goldschmidt, Inc. Typical functionalized siloxanes are amine functionalized siloxanes, where the functionalization is typically at the end of the siloxane.

Examples of organosiloxanes are marketed under the trade name Silwet by Witco Corporation. Such organosiloxanes typically have an average weight molecular weight of about 350 to about 15,000, are hydrogen or C ₁ -C ₄ alkyl capped, and may be hydrolyzable or non-hydrolyzable. Typical organosiloxanes are those sold under the trade names Silwe L-77, L-7602, L-7604 and L-7605, which are polyalkylene oxide modified dialkyl polysiloxanes.

Examples of suitable anionic dispersants include (C ₈ -C ₁₆ ) alkylbenzene sulfonates, (C ₈ -C ₁₆ ) alkane sulfonates, (C ₈ -C ₁₈ ) α-olefin sulfonates, α-sulfo (C _8- C ₁₆ ) fatty acid methyl esters, (C ₈ -C ₁₆ ) fatty alcohol sulfates, mono- or di-alkyl sulfosuccinates, wherein each alkyl is independently a (C ₈ -C ₁₆ ) alkyl group), alkyl ether Sulfates, (C ₈ -C ₁₆ ) salts of carboxylic acids or isethionates having fatty acid chains of about 8 to about 18 carbon atoms, for example sodium diethylhexyl sulfosuccinate, sodium methyl benzene sulfonate or sodium bis ( 2-ethylhexyl) sulfosuccinate (eg, Aerosol OT or AOT) is included.

Typically, the dispersant is a compound selected from organosiloxanes, functionalized organosiloxanes, alkyl substituted pyrrolidones, polyoxyalkylene ethers or ethylene oxide propylene oxide block copolymers.

Examples of commercially available dispersants include cyclic organo-silicones (e.g. SF1204, SF1256, SF1328, SF1202 (decamethyl-cyclopentasiloxane (pentamer)), SF1258, SF1528, Dow Corning 245 fluid, Dow Corning 246 fluid, Dode Carmethyl-cyclo-hexasiloxane (hexime) and SF1173); Copolymers of polydimethylsiloxane and polyoxyalkylene oxides (eg, SF1488 and SF1288); Linear silicon containing oligomers (eg, Dow Corning 200 (R) fluid); Sylwet L-7200, Sylwet L-7600, Sylwet L-7602, Sylwet L-7605, Sylwet L-7608 or Sylwet L-7622; Nonionic surfactants such as Triton X-100, Igepal CO-630, PVP series, Airvol 125, Airball 305, Airball 502 and Airball 205; Organic polyethers such as Surfynol 420, Surfinol 440 and Surfinol 465; Or Solsperse 41000.

Examples of other commercially available dispersants include SF1173 (GE Silicone); Organic polyethers such as Sufinol 420, Sufinol 440 and Sufinol 465 (manufactured by Air Products Inc.); Sylwet L-7200, Sylwet L-7600, Sylwet L-7602, Sylwet L-7605, Sylwet L-7608 or Sylwet L-7622 (from Witco) or nonionic surfactants such as Triton X-100 (Dow Chemical), Igepal CO-630 (Rhodia), PVP Series (ISP Technologies) and Solsperth 41000 (Avecia) .

The amount of dispersant is in the range of 0 to 5% by weight. More typically, the amount of dispersant is from 0.1 to 2% by weight. Silanes are typically used at concentrations of from 40 to 200 mol%, in particular from 60 to 150 mol%, relative to the molecular weight surface active sites on the nano-sized particulate filler surface. In general, the binder formulation comprises up to about 5 weight percent dispersant, such as about 0.1 to about 5.0 weight percent dispersant, based on the total weight of the binder formulation.

The binder formulation may further comprise a dispersed phase suspended in an external phase. The outer phase typically comprises a polymer component. The dispersed phase generally comprises a particulate filler. Particulate fillers are inorganic particles such as metals (eg steel, silver or gold) or metal complexes such as metal oxides, metal hydroxides, metal sulfides, metal halide complexes, metal carbides, metal phosphates, inorganic salts ( For example, it may be formed of particles of CaCO ₃ ), ceramic, or a combination thereof. Examples of metal oxides include ZnO, CdO, SiO ₂ , TiO ₂ , ZrO ₂ , CeO ₂ , SnO ₂ , MoO ₃ , WO ₃ , Al ₂ O ₃ , In ₂ O ₃ , Fe ₂ O ₃ , La ₂ O ₃ , Fe ₂ O ₃ , CuO, Ta ₂ O ₅ , Sb ₂ O ₃ , Sb ₂ O _5, or a combination thereof. Mixed oxides containing different metals may also be present. Nanoparticles can include particles selected from the group consisting of, for example, ZnO, SiO ₂ , TiO ₂ , ZrO ₂ , SnO ₂ , Al ₂ O ₃ , coformed silica alumina, and mixtures thereof. Nanometer sized particles may also have organic components such as carbon black, highly crosslinked / core shell polymer nanoparticles, organic modified nano sized particles, and the like. Such fillers are described, for example, in US Pat. No. 6,467,897 and WO 98/51747, which is incorporated herein by reference.

Particulate fillers formed via solution-based processes, such as sol-formed and sol-gel-formed ceramics, are particularly suitable for use in the formation of composite binders. Suitable sols are commercially available. For example, colloidal silica in aqueous solution may be manufactured under the trade name “LUDOX” (EI DuPont de Nemours and Co., Inc.), Dela, USA. Wilmington, Wet, NYACOL (Nyacol Co., Ashland, Mass.) And NALCO (Nalco Chemical Co., Ltd.) Co., Ltd., Oak Brook, Illinois, USA. Many commercially available sols are basic and stabilized with alkalis such as sodium hydroxide, potassium hydroxide or ammonium hydroxide. Further examples of suitable colloidal silicas are described in US Pat. No. 5,126,394, which is incorporated herein by reference. Sol-formed silica and sol-formed alumina are particularly suitable. The sol can be functionalized by reacting one or more suitable surface treatment agents with the inorganic oxide based particles in the sol.

In certain embodiments, the particulate filler is sub-micron in size. For example, the particulate filler may be a nano-sized particulate filler, eg, a particulate filler having an average particle size of about 3 to about 500 nm. In an exemplary embodiment, the particulate filler has an average particle size of about 3 to about 200 nm, for example about 3 to about 100 nm, about 3 to about 50 nm, about 8 to about 30 nm or about 10 to about 25 nm. In certain embodiments, the average particle size is about 500 nm or less, for example about 200 nm or less, less than about 100 nm or about 50 nm or less. For particulate fillers, the average particle size can be defined as the particle size corresponding to the peak volume fraction in the small angle neutron scattering (SANS) distribution curve or the particle size corresponding to the 0.5 cumulative volume fraction of the SANS distribution curve.

Particulate fillers can also be characterized by narrow distribution curves having half widths of up to about 2.0 times the average particle size. For example, the half width may be about 1.5 or less or about 1.0 or less. The half width of the distribution is half the distribution width at half the maximum height, for example half the particle fraction at the distribution curve peak. In certain embodiments, the particle size distribution is bi-modal or has one or more peaks in the particle size distribution.

In certain embodiments, the binder formulation may comprise two or more 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 made of the same material or different materials. For example, each of the particulate fillers may be formed from silica. In another example, one filler may be formed of silica and another filler may be formed of alumina. In one example, each of the particulate fillers has a particle size distribution with an average particle size of about 1000 nm or less, such as about 500 nm or less or less than about 100 nm. In another example, one of the particulate fillers has a particle size distribution having an average particle size of about 1000 nm or less, such as about 500 nm or less or less than about 100 nm, and the second particulate filler has an average particle size of greater than about 1 μ, for example For example, about 1 to about 10 microns or about 1 to about 5 microns. Alternatively, the second particulate filler may have a large average particle size, such as 1500 μ. In certain embodiments, a binder formulation comprising a first particulate filler having an average particle size of less than microns and a second particulate filler having an average particle size of greater than 1 micron advantageously provides improved mechanical properties when cured to form the binder. do.

Typically, the second particulate filler has a low aspect ratio. For example, the second particulate filler may have an aspect ratio of about 2 or less, for example about 1 or about spherical. Generally, the second particulate filler is untreated and does not cure through the treatment. In contrast, abrasive particles are typically cured fine particles having an aspect ratio of at least about 2 and sharp edges.

When selecting the second particulate filler, the settling speed and speed are generally considered. As the size increases, particulate fillers larger than 1 micron tend to settle more quickly, but show lower viscosity at higher loads. In addition, the refractive index of the particulate filler may also be considered. For example, the particulate filler may be selected at a refractive index of about 1.35 or greater. In addition, the particulate filler may be selected to not contain basic residues, since the basic residues may adversely affect the polymerization of the cationic polymerization component.

Particulate fillers are generally dispersed in a binder formulation. Prior to curing, the particulate filler is dispersed in a colloidal state in the binder suspension and cured to form a colloidal composite binder. For example, the particulate material can be dispersed such that the Brownian motion sustains the particulate filler in the suspension. Generally, particulate fillers are substantially free of particulate aggregates. For example, the particulate filler can be substantially monodisperse such that the particulate filler is dispersed as a single particle, especially if present, for example, only having meaningless particulate aggregation.

In certain embodiments, the particles of particulate filler are substantially spherical. Alternatively, the particles may have a primary aspect ratio greater than 1, for example about 2 or more, about 3 or more or about 6 or more, where the primary aspect ratio is the ratio of the longest dimension to the shortest dimension orthogonal to the longest dimension. Particles can be characterized by a secondary aspect ratio defined as the ratio of orthogonal dimensions in a plane generally perpendicular to the longest dimension. The particles may be acicular, for example, having a primary aspect ratio of about 2 or more and a secondary aspect ratio of about 2 or less, for example about 1. Alternatively, the particles may be plate-like, eg, have an aspect ratio of at least about 2 and a secondary aspect ratio of at least about 2.

In an exemplary embodiment, the particulate filler is prepared in aqueous solution and mixed with a suspension of the binder formulation. The process for the preparation of such suspensions comprises the steps of introducing an aqueous solution, for example an aqueous silica solution, polycondensing the silicate to a particle size of, for example, 3 to 50 nm, adjusting the resulting silica sol to an alkaline pH, Optionally concentrating the sol, mixing the sol with the suspension component on the external fluid and optionally removing water or other solvent components from the suspension. For example, an aqueous solution of silicate, for example an alkali metal silicate solution (eg, sodium silicate or potassium silicate solution) having a concentration in the range of 20 to 50% by weight, is introduced. The silicates are polycondensed to 3-50 nm particle size, for example by treating the alkali metal silicate solution with an acidic ion exchanger. The resulting silica sol is adjusted to alkali pH (eg pH> 8) to stabilize for further polycondensation or aggregation of the particles present. Optionally, the sol can be concentrated, for example, by distillation, usually to a concentration of SiO ₂ of about 30 to 40 weight percent. The sol is mixed with the components on the external fluid. The water or other solvent component is then removed from the suspension. In certain embodiments, the suspension is substantially free of water.

The outer phase fraction in the precured binder formulation, which generally comprises an organic polymer component, is, as a percentage of the binder formulation, about 20 to about 95 weight percent, for example about 30 to about 95 weight percent, typically about 50 To about 95 weight percent, even more typically about 55 to about 80 weight percent. The fraction on the dispersed particulate filler may be about 5 to about 80 weight percent, for example about 5 to about 70 weight percent, typically about 5 to about 50 weight percent, more typically about 20 to about 45 weight percent. . Particulate fillers colloidal and submicron as described above are at least about 5% by weight, for example at least about 10% by weight, at least about 15% by weight, at least about 20% by weight or at least about 40% by weight. useful. In contrast to conventional fillers, solution formed nanocomposites have a lower viscosity at higher loads and improved processing properties. The amount of components is expressed as weight percent of the component relative to the total weight of the binder formulation, unless otherwise specified.

In certain embodiments, the binder formulation comprises about 10 to about 90 weight percent cationic polymerizable compound, up to about 40 weight percent radically polymerizable compound and about 5 to about 80 weight percent based on the total weight of the binder formulation. Particulate fillers. The total amount of the binder formulation component is added at 100% by weight and, for example, when the amount of one or more components is specified, the amount of other components is understood to correspond to the amount such that the sum of the amounts does not exceed 100% by weight. do.

The cationic polymerizable compound includes, for example, an epoxy functional component or an oxetane functional component. For example, the binder formulation comprises about 10 to about 60 weight percent cationic polymerizable compound, such as about 20 to about 50 weight percent cationic polymer compound, based on the total weight of the binder formulation. can do. Exemplary binder formulations may comprise up to about 20 weight percent, for example about 5 to about 20 weight percent mono or poly glycidyl ethers of aliphatic alcohols, aliphatic polyols, polyesterpolyols or polyetherpolyols. Exemplary binder formulations contain up to about 50% by weight of a component having a polyether backbone, for example about 5% to about 50% by weight, for example, polytetramethylenediol, glycidylether of polytetramethylenediol, poly Polytetramethylenediol containing an acrylate or one or more polycarbonate groups of tetramethylenediol.

Radical polymerizable compounds of the above examples include compounds containing, for example, one or more methacrylate groups, for example components having three or more methacrylate groups. In another example, the binder formulation includes up to about 30 weight percent, for example up to about 20 weight percent, up to about 10 weight percent, or up to about 5 weight percent radically polymerizable compound.

The formulation further comprises about 20% by weight or less, for example about 0.1 to about 20% by weight of cationic photoinitiator, or about 20% by weight or less, for example about 0.1 to about 20% by weight of radical photoinitiator. can do. For example, the binder formulation may comprise up to about 10 weight percent, for example up to about 5 weight percent cationic photoinitiator. In another example, the binder formulation may comprise up to about 10 weight percent, for example up to about 5 weight percent of free radical photoinitiators.

Particular fillers include dispersed particulates of submicron size. In general, the binder formulation comprises 5 to 80% by weight, for example 5 to 60% by weight, for example 5 to 50% or 20 to 45% by weight of microparticle fillers. Particular embodiments include at least about 5% by weight, for example at least about 10% or at least about 20% by weight particulate filler. In one particular embodiment, the particulate filler is a solution formed from silica particulates and may be dispersed in the colloidal phase in the polymer component. Exemplary binder formulations are up to about 5% by weight, for example selected from organosiloxanes, functionalized organosiloxanes, alkyl substituted pyrrolidones, polyoxyalkylene ethers, and ethylene oxide propylene oxide block copolymers. It does not further comprise 0.1 to 5% by weight of dispersant.

In certain embodiments, the binder formulation is formed by mixing nanocomposite epoxy or acrylate precursors, ie, precursors comprising particulate fillers of microns or less. For example, the binder formulation may comprise up to about 90% by weight nanocomposite epoxy and may comprise an acrylic precursor, such as up to 50% by weight acrylic precursor. In another example, the nanocomposite acrylic precursor can be mixed with the epoxy.

Binder formulations comprising polymeric or monomeric components and comprising dispersed particulate filler can be used to form a base coating, a secondary coating, a flexible coating, or a substrate coating of a coated abrasive article. In an exemplary process of forming a primary coating, a binder formulation is coated on a substrate, abrasive particles are applied over the primary coating, and the primary coating is partially cured before patterning. The secondary coating is applied over the primary coating and the abrasive particles. In another exemplary embodiment, the binder formulation can be blended with the abrasive particles to coat the substrate and partially cure to form a patterned polishing slurry.

The abrasive particles are silica, alumina (smoke or sinter), zirconia, zirconia / alumina oxide, silicon carbide, garnet, diamond, cubic boron nitride, silicon nitride, cerium oxide, titanium dioxide, titanium diboride, boron carbide, tin oxide, carbide It may be formed from one or a combination of abrasive particles including tungsten, titanium carbide, iron oxide, chromium, flint, diamond steel. For example, the abrasive particles are silica, alumina, zirconia, silicon carbide, silicon nitride, boron nitride, garnet, diamond, co-melted alumina zirconia, cerium oxide, titanium diboride, boron carbide, flint, gold steel, aluminum nitride, and mixtures thereof. It may be selected from the group consisting of. Certain embodiments can in principle be produced using dense abrasive particles consisting of alpha-alumina.

The abrasive particles can have a particular shape. Examples of such shapes include rods, triangles, pyramids, cones, worms, hollow spheres and the like. Alternatively, the abrasive particles may be random in shape.

The abrasive particles may generally have an average particle size of 2000 microns or less, for example about 1500 microns or less. In another example, the abrasive particle size is about 750 μm or less, for example about 350 μm or less. For example, the abrasive particle size may be at least 0.1 μ, for example about 0.1 to about 1500 μ, more typically about 0.1 to about 200 μ or about 1 to about 100 μ. The particle size of the abrasive particles is typically specified to be the longest dimension of the abrasive particles. In general, there is a range distribution of particle sizes. In some instances, the particle size distribution is tightly controlled.

In the blended abrasive slurry comprising the abrasive particles and the binder formulation, the abrasive particles provide about 10 to about 90 weight percent abrasive slurry, for example, about 30 to about 80 weight percent.

The abrasive slurry may further include a grinding aid to increase grinding efficiency and cutting speed. Useful grinding aids are inorganic, such as halide salts such as sodium creolite and potassium tetrafluoroborate; Or organic, such as chlorinated wax, such as polyvinyl chloride. Specific embodiments include cryolites and potassium tetrafluoroborate having particle sizes of 1 to 80 microns, most commonly 5 to 30 microns. The weight percent of grinding aid is generally up to about 50 weight percent of the total slurry (including the abrasive particles), for example about 0 to about 50 weight percent, most typically about 10 to 30 weight percent.

Binder formulations may be useful for the formation of structured abrasive products. For example, the binder formulation can be coated over the substrate, partially cured, and then patterned to form the abrasive structure. In certain embodiments, the structured abrasive product can be formed without the use of functional powders.

2 includes a diagram of an example process. Substrate 202 is provided from roll 204. The substrate 202 is coated with a binder formulation 208 dispensed from the coating device 206. Examples of the coating apparatus include a dropping die coater, a knife coater, a curtain coater, a vacuum die coater or a die coater. The coating method can be a contact or non-contact coating method. Such methods include two rolls, three roll transitions, a knife on a roll, slot die, gravure, extrusion or spray coating application.

In certain embodiments, binder formulation 208 is provided in a slurry comprising the formulation and abrasive particles. In another embodiment, the binder formulation 208 is dispensed separately from the abrasive particles. The abrasive particles, together with the binder formulation 208, are provided after partial curing of the binder formulation 208, after patterning of the binder formulation 208 or after complete curing of the binder formulation 208, after coating of the substrate 202. Can be. The abrasive particles can be applied by, for example, electrostatic coating, immersion coating or mechanical injection.

The binder formulation is partially cured through the energy source 210. The choice of energy source 210 depends in part on the chemistry of the binder formulation. The energy source 210 may be a source of thermal energy or actinic radiation energy, for example electron beams, ultraviolet light or visible light. The amount of energy used depends on the chemical nature of the reactive groups in the precursor polymer component and the thickness and density of the binder formulation 208. For thermal energy, oven temperatures of about 75 ° C. to 150 ° C. and periods of about 5 minutes to about 60 minutes are generally sufficient. Electron beam radiation or ionizing radiation may be used at energy levels of about 0.1 MRad to about 100 MRad, in particular about 1 MRad to about 10 MRad. Ultraviolet radiation includes radiation having a wavelength range of about 200 to about 400 nm, especially about 250 to 400 nm. Visible radiation includes radiation having a wavelength range of about 400 to about 800 nm, especially about 400 to about 550 nm. Curing parameters, such as exposure, are generally formulation dependent and can be controlled through lamp power and belt speed.

In an exemplary embodiment, energy source 210 provides actinic radiation to the coated substrate to partially cure binder formulation 208. In another embodiment, the binder formulation 208 is heat curable and the energy source 210 provides heat for heat treatment. In further embodiments, the binder formulation 208 may comprise actinic radiation curable and thermally curable components. Thus, the binder formulation may be partially cured through the first heat and actinic radiation cure, and may be cured until complete curing through the second heat and actinic radiation cure. For example, the epoxy component of the binder formulation may be partially cured using ultraviolet electromagnetic radiation, and the acrylic component of the binder formulation may be further cured through thermal curing.

In certain embodiments, the binder formulation 208 has a viscosity of 3000 cps or less when measured at room temperature (21 ° C. or 70 ° F.). For example, the binder formulation 208 before curing may have a viscosity at room temperature of about 2000 cps or less, for example about 1500 cps or less, about 1000 cps or less, or about 500 cps or less. Alternatively, the binder formulation 208 may have a viscosity greater than 3000 cps. Uncured binder formulations, as such or in abrasive slurries, generally flow at the temperature and pressure at which the coating process is performed. For example, the uncured binder formulation may flow at a temperature of about 60 ° C. (140 ° F.) or less. The binder formulation 208 may be partially cured, for example, to a viscosity of at least about 10,000 cps, for example at least about 20,000 cps or at least about 50,000 cps, as measured at room temperature prior to patterning. For example, the partially cured binder formulation may have a viscosity of at least about 100,000 cps, for example at least about 500,000 cps, as measured at room temperature. In another embodiment, the partially cured binder formulation may have a viscosity of less than 10,000 cps. Partially cured binder formulations are typically viscous liquids that can flow under certain temperatures and pressures. For example, the partially cured binder formulation can be printed in a pattern under pressure. In general, partially cured binder formulations are more viscous than binder formulations. In particular, the partially cured binder formulation has a viscosity index of at least about 1.1, wherein the viscosity index is defined as the ratio of the viscosity of the partially cured binder formulation at room temperature to the viscosity of the uncured binder formulation at room temperature. For example, the partially cured binder formulation may have a viscosity index of at least about 2.0, such as at least about 5.0 or at least about 10.0. In certain embodiments, nanocomposite binders, particularly sol formed nanocomposite binders, are well suited for this application.

With reference to FIG. 2, when partially curing the binder formulation 208, a pattern is imparted to the partially cured binder, for example via rotogravure 212. Alternatively, the pattern can be formed in the partially cured binder through stamping or compression. Typically, embossing rolls produce the desired surface structure in a continuous web process. Embossing rolls are used in rotating coating lines and can be described as nip roll alignment, where one roll is a substrate roll and another roll is an "etching" or embossing roll. Compression of the web coated in this nip provides a "positive" image of the embossing roll over the web. Such embossing rolls often have recesses that distinguish them from standard gravure or anilox rolls used in the printing industry.

The example patterning tool can be heated. Typically, the patterning forms a repeating pattern of the abrasive structure. In certain embodiments, patterning is performed without functional powder. Alternatively, the functional powder may be applied to the binder formulation 208 before or after partial curing of the binder formulation 208.

The patterned binder formulation is then fully cured or cured to achieve the desired mechanical properties. Curing may be facilitated through an energy source or the binder formulation may be aligned to cure over time. For example, the patterned binder formulation can be further cured by the energy source 214. The energy source 214 may supply actinic radiation or thermal energy to the binder formulation depending on the curing mechanism of the binder formulation.

Upon curing the binder formulation, a structured abrasive product is formed. Alternatively, a secondary coating may be applied to the patterned abrasive structure. In certain embodiments, the structured abrasive product is rolled over roll 216. In another embodiment, complete curing may be performed after rolling of the partially cured abrasive article.

In another embodiment, the secondary coating can be applied to the binder formulation and the abrasive particles. For example, the secondary coating can be applied before partial curing of the binder formulation, after partial curing of the binder formulation, after patterning of the binder formulation, or after further curing of the binder formulation. The secondary coating can be applied by roll coating or spray coating, for example. Depending on the composition of the secondary coating (if applied), the secondary coating may be cured in combination with the binder formulation or separately. A supersize coating comprising a grinding aid can be applied over the secondary coating to cure with the binder formulation, and to cure with the secondary coating or separately.

Certain embodiments of the method are advantageous for the production of structured abrasive articles. This embodiment produces an abrasive article comprising a binder with improved mechanical properties. In particular, some embodiments reduce stress in the abrasive product and improve the performance properties of the abrasive product, such as haze and surface quality. Embodiments of the method may also increase the load of abrasive particles, thereby improving abrasive product life and improving stock removal rates.

Exemplary Binder Formulations

Examples 1-5 describe exemplary binder formulations comprising a polymer component and nano-sized particulate filler.

Example 1

Exemplary binder formulations include 40 weights and epoxy resins, including Nanopox XP 22/0314, 3,4-epoxy cyclohexyl methyl-3,4-epoxy cyclohexyl carboxylate, available from Hanse Chemie. % Colloidal silica particulate filler. The binder formulation also includes UVR 6105 comprising 3,4-epoxy cyclohexyl methyl-3,4-epoxy cyclohexyl carboxylate, but no particulate filler. Binder formulations may further include polyols (4,8-bis (hydroxymethyl) tricyclo [5.2.1.0] decane), cationic photoinitiators (Chivacure 1176), radical photoinitiators (Irgacure 2022, commercially available from Ciba). And acrylate precursors (SR 399, dipentaerythritol pentaacrylate, commercially available from Atofina-Sartomer, Exton, Pa.). Table 1 describes the component concentrations in the binder formulation.

ingredient 1.1 wt% 1.2 wt% 1.3 wt% 1.4 wt% 1.5 wt% Nanofox XP 22/0314 0.00 20.00 40.00 60.00 79.92 UVR 6105 79.92 59.92 39.92 19.92 0.00 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0] decane 13.50 13.50 13.50 13.50 13.50 Irgacure 2022 0.48 0.48 0.48 0.48 0.48 Sivacure 1176 1.50 1.50 1.50 1.50 1.50 SR 399 4.60 4.60 4.60 4.60 4.60 result Filler% 0.00 8.00 16.00 24.00 31.97

Example 2

In another example, the binder formulation is teratan 250, teratan 1000, 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0] decane, 2-ethyl-1,3-hexanediol and 1,5- One polyol selected from the group consisting of pentanediol. The selected polyols are mixed with Nanofox XP 22/0314, Irgacure 2022, Sivacure 1176 and Nanocryl XP 21/0940. Nanokrill XP 21/0940 is an acrylate precursor (tetraacrylate) containing 50% by weight of colloidal silica particulate filler, commercially available from Hanse Chemie (Berlin, Germany). Concentrations are listed in Table 2.

ingredient 2.1 wt% 2.2 wt% 2.3% by weight 2.4 wt% 2.5% by weight Nanofox XP 22/0314 74.46 74.46 74.46 74.46 74.46 Irgacure 2022 0.48 0.48 0.48 0.48 0.48 Sivacure 1176 1.50 1.50 1.50 1.50 1.50 Nano Krill XP 21/0940 11.06 11.06 11.06 11.06 11.06 Terran 250 12.49 Terratan 1000 12.49 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0] decane 12.49 2-ethyl-1,3-hexanediol 12.49 1,5-pentanediol 12.49 result Filler (%) 35.32 35.32 35.32 35.32 35.32 Tg (tan δ) 84.25 116.55 139.8 93.6 53.85 E '(MPa) at 23 ° C 2374.5 2591.5 3258 2819.5 1992

Example 3

In this example, three acrylate resins [nanocrylic XP 21/0940 (tetraacrylate), nanocrylic XP 21/0930 (diacrylate) and nanocrylic 21/0954 (trimethylolpropane ethoxy triacrylate) ; Each containing 50% by weight of colloidal silica particulate filler, each commercially available from Hanse Chemie]. Binder formulations further include Nanopox XP 22/0314, 1,5-pentanediol, Irgacure 2022 and Sivacure 1176. The composition is listed in Table 3.

ingredient 3.4 wt% 3.5 wt% 3.6% by weight Nanofox XP 22/0314 77.28 77.28 77.28 1,5-pentanediol 15.46 15.46 15.46 Irgacure 2022 0.52 0.52 0.52 Sivacure 1176 1.50 1.50 1.50 Nano Krill XP 21/0940 5.15 Nano Krill XP 21/0930 5.15 Nanokrill XP 21/0954 5.15 result Filler% 33.49 33.49 33.49

Example 4

In a further example, two epoxy components [nanopox XP 22/0314 and nanopox 22/0516 (bisphenol A diglycidylether) with nano-sized silica particulate filler; Each commercially available in Hanse Chemi]. In addition, an oxetane component and OXT-212 (3-ethyl-3- (2-ethylhexyloxymethyl) oxetane) are included. Polyols (terratan 250) and photocatalysts (Sivacure 1176). The composition is listed in Table 4.

ingredient 4.1 wt% 4.2 wt% 4.3 wt% 4.4 wt% Nanofox XP 22/0314 67.89 58.19 48.50 38.80 Nanofox XP 22/0516 9.70 19.40 29.10 38.80 Terran 250 9.70 9.70 9.70 9.70 OXT-212 9.70 9.70 9.70 9.70 Sivacure 1176 2.91 2.91 2.91 2.91 result Filler% 31.04 31.04 31.04 31.04

Example 5

In another example, a sample is prepared using a secondary coating having a binder formulation described in Table 5. The binder formulation comprises nanosized filler particulates supplied with the addition of Nanofox A 610 and micron sized fillers (NP-30 and ATH S-3) with an average particle size of 3μ. NP-30 includes spherical silica particulates having an average particle size of about 3 microns. ATH S-3 comprises aspheric alumina anhydride having an average particle size of about 3μ. The sample has a Young's modulus of 8.9 GPa (1300 ksi), a tensile strength of 77.2 MPa (11.2 ksi), and an elongation at break of 1%.

ingredient weight% UVR-6105 0.71 Heloxie 67 6.50 SR-351 2.91 DPHA 1.80 (3-glycidoxyoxy) trimethoxysilane 1.17 Sivacure 184 0.78 NP-30 46.71 ATH S-3 7.78 Nanofox A 610 27.75 Sivacure 1176 3.89 SDA 5688 0.00072

The foregoing objects are intended to be illustrative and should not be considered limiting, and the appended claims are intended to cover all modifications, improvements, and other aspects falling within the true scope of the invention.

Claims (41)

Coating the substrate with a binder formulation; Partially curing the binder formulation; And Forming a pattern in the partially cured binder formulation. The method of claim 1, further comprising completely curing the binder formulation after pattern formation. The method of claim 2, wherein the step of fully curing the binder formulation after pattern formation comprises exposing the binder formulation to actinic radiation. The method of claim 2, wherein the step of fully curing the binder formulation after pattern formation comprises heat curing. The method of claim 1, further comprising applying abrasive particles over the binder formulation. The method of claim 5, wherein applying the abrasive particles comprises applying the abrasive particles prior to partially curing the binder formulation. The method of claim 5, further comprising applying a size coat over the abrasive particles. 8. The method of claim 7, wherein applying the secondary coating comprises coating the secondary coating prior to partially curing the binder formulation. delete delete The method of claim 1, wherein partially curing the binder formulation comprises exposing the binder formulation to actinic radiation. delete The method of claim 1, wherein partially curing the binder formulation comprises partially curing the binder formulation to a viscosity index of at least 1.1. delete The method of claim 1, further comprising mixing the binder formulation with the abrasive particles to form an abrasive slurry. delete delete The method of claim 1, wherein forming the pattern comprises forming a pattern using a heating patterning tool. The method of claim 1, wherein forming the pattern comprises printing in rotogravure. The method of claim 1, wherein forming the pattern comprises stamping the pattern. The method of claim 1, further comprising coating the substrate with a flexible coating prior to coating with the binder formulation. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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