Abstract: The invention relates to a thermosettable adhesive comprising a thermosettable polymer component, a thermoformable polymer component, an effective amount of a heat-activatable and/or photoactivatable curing system for curing the thermosettable polymer component, and from 0.5-20 wt. % with respect to the mass of the thermosettable adhesive of one or more hydroxides and/or hydroxyoxides of Al, Mg and/or Zr.

Abstract: The present invention relates to a process for the production of three-dimensional articles by stereolithography using a radiation-curable composition comprising a mixture of at least one cationically polymerizable compound and/or at least one free radical polymerizable compound, at least one filler material and at least one photoinitiator for cationic and/or radical polymerization. An organic viscosity stabilizer material may be brought into contact with the composition to substantially delay or prevent undesirable viscosity increase and subsequently premature polymerization. A filler material is optionally added to the composition in an effective amount to at least delay or prevent a significant increase in viscosity and polymerization. The process is particularly suitable for stabilizing resins in stereolithography baths.

Abstract: A radiation-curable composition in a liquid or solid form comprises at least one solid, non-crystalline radiation-transmissible material, dispersed in at least one cationic-curable or free-radical curable composition or mixture thereof. The solid, non-crystalline radiation-transmissible materials comprise glasses and other suitable materials that transmit (i.e., are transparent to) at least about 40% of radiation having a wavelength from about 180 to about 600 nanometers. The solid forms of the radiation-curable compositions of the invention are useful as powder coatings for coating decorative and functional objects and that would be cured by a thermal heating flow process followed by radiation exposure. The cured compositions of the invention are useful as coatings and inks for metal, paper, plastics, glass, ceramics, and wood, as adhesives, as sealants, and as composite materials and other articles and in biomedical and dental applications.

Abstract: A method of preparing a sterile article is disclosed. A polymer having a halogen-containing repeating unit is prepared that contains about 0.

Abstract: A UV-polymerizable formulation comprising a polymerizable formulation and an aluminum trihydrate filler with a particle size of from 1 to 10 micrometers. The formulation is intended for use in the production of coated abrasives can be used to produce a very much thicker coating if a UV-transparent filler is used.

Abstract: Disclosed are a photosensitive composition which is developable with an aqueous alkaline solution and such calcined patterns as a conductor pattern, a vitreous dielectric pattern, and a fluorescent pattern which are obtained by the use of the photosensitive composition. The photosensitive composition comprises (A) a carboxyl group-containing photosensitive polymer obtained by the reaction of a copolymer of (a) a compound containing an unsaturated double bond and a carboxyl group and (b) an unsaturated double bond-containing compound with (c) a compound containing an unsaturated double bond and an epoxy group, (B) a diluent, (C) a photopolymerization initiator, (D) an inorganic powder, and (E) a stabilizer. The composition may be in the form of paste or in the form of a dry film. When the photosensitive composition is in the form of paste, the paste is applied to a substrate and then dried to form a film. When the photosensitive composition is in the form of a dry film, the film is laminated on the substrate.

Abstract: A display member, particularly a plasma display member, can be produced by a process comprising applying a paste which comprises a urethane compound and inorganic fine particles onto a substrate and then firing the paste. The display member has a post-firing pattern without any defect.

Abstract: The invention relates to a process for producing foamed polyolefin-based plastics blocks by first crosslinking a matrix comprising a) from 51 to 97% by weight of one or more polyolefins, selected from the group consisting of polyethylene and ethylene copolymer, b) from 3 to 20% by weight of a foaming agent, using &bgr;-radiation of energy >6 MeV. The thickness of the matrix is from 25 to 45 mm. The radiation dose is from 20 to 150 kJ/kg. During the irradiation, atmospheric oxygen is at least substantially prevented from reaching the surface of the matrix. After crosslinking, the crosslinked matrix is foamed by heating to a temperature >160° C. and decomposing the blowing agent.

Abstract: The invention relates to a photopolymerizable composite resin composition for dental restoration i) based on the multifunctional prepolymer mixture of 2,2-bis-(4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl)propane (“Bis-GMA”) and multifunctional prepolymer formed by substituting hydrogen atoms in hydroxyl group with methacrylate groups in this Bis-GMA molecules, and ii) comprising a diluent, an inorganic filler, a photoinitiation system, and other additives. The photopolymerizable composite resin composition for dental restoration based on multifunctional prepolymer mixture has better physical and mechanical properties and biocompatibility than the conventional composition based on only Bis-GMA itself.

Abstract: Fluid silico-acrylic compositions, which can be polymerised by heat and radiation, by radical-type mechanism, with very low water (less than 1%) and volatile solvent content, containing silica, a silane and a multifunctional acrylic monomer, in which the silica is in the form of individualised particles, with a mean diameter of between 40 and 100 nm, not linked to each other by siloxane bonds, and the silane is a vinylsilane of formula (I) H2C═CH—Si(OR)3  (I) in which R represents a methyl or ethyl radical and the multifunctional acrylic monomer is 1,6-hexanediol diacrylate, and which are transparent, colourless and stable over time.

Abstract: An ultraviolet curable ink for stencil printing having a high yield value, hence excellent on-machine stability, is provided, which comprises an ultraviolet curable resin, a pigment, and an organic clay treated with a specific quaternary ammonium salt including a hectorite or bentonite based organic clay treated with dimethyl di(hydrogenated tallow) ammonium (DMDHT) salt.

Abstract: This invention relates to radiation-curable coating compositions which contain A) compounds having one or more free-radically polymerisable double bonds which additionally contain at least one further functional group reactive for the purposes of an addition and/or condensation reaction, B) compounds having one or more free-radically polymerisable double bonds, which additionally contain at least one further functional group reactive for the purposes of an addition and/or condensation reaction, wherein the additional reactive functional group is complementary to or reactive towards the additional reactive functional groups of component A), C) optionally at least one monomeric, oligomeric and/or polymeric compound having at least one functional group reactive towards the functional groups from component A) or component B) D) one or more photoinitiators as well as E) optionally solvents, water, pigments and/or extenders as well as conventional lacquer additives, wherein component A) and component B) diffe

Abstract: The present invention is directed to silicone formulations which are capable of being rapidly cured to tough elastomeric materials through exposure to UV radiation, and optionally through exposure to moisture as well. The cured products demonstrate high resistance to flammability and combustibility. The flame-retardant components is a combination of hydrated alumina and an organo ligand complex of a transition metal or an organosiloxane ligand complex of a transition metal or a combination thereof.

Abstract: Photoinitiator combinations comprising

Abstract: A coating composition forming a abrasion resistant coating comprising (A) an ultraviolet-curable silicone prepared by chemically modifying particulate colloidal silica with a specific silane compound, (B) a monomer mixture comprising a (meth)acrylate having a specific isocyanate skeleton and a urethane poly(meth)acrylate having an alicyclic skeleton, and (C) a photo-polymerization initiator. By using a urethane poly(meth)acrylate having an alicyclic skeleton as part of the component (B) and the component (A) having an enhanced reactivity of chemical modification, the compatibility of the component (A) with the component (B) is improved to give a cured coating with excellent wear resistance, weather resistance and durability.

Abstract: A multilayer circuit board having a resolution in the range of 25-80 &mgr;m, and blind via-holes between layers, the blind via-holes having an aspect ratio in the range of 2.0-0.6 for effecting access between the layers, wherein an insulating layer having the blind via-holes between the layers has a glass transition temperature in the range of 150-220° C., and an epoxy group photosensitive resin composition is used therefor. A photosensitive resin composition having a preferable resolution and heat resistance is obtained. A multilayer circuit board is provided in which the thermal stress generated in the steps of a reflow process, a gold wire bonding process and a repairing process in a bare chip mounting process are reduced, and peeling off of the conductor wiring and deformation of the multilayer circuit board caused by mechanical stresses during the heating processes are suppressed. Accordingly, a decrease in the size and weight of an electronic apparatus is possible.

Abstract: A dental restorative material is disclosed, comprising an amorphous inorganic material having a refractive index in a D-line of sodium in the range of 1.470˜1.520 and having an X-ray opacity; a (meth)acrylic ester monomer not having a benzene ring in a molecule thereof; and a polymerization initiator, if desired, the dental restorative material according to the invention further comprises an amorphous inorganic material having a refractive index in a D-line of sodium equal to or less than that of the (meth)acrylic ester monomer not having a benzene ring in a molecule thereof, the dental restorative material of the invention has an X-ray opacity and translucency close to natural teeth, and has superior esthetics not using a monomer having a benzene ring which has a fear of an environmental hormone action.

Abstract: Fluid silico-acrylic compositions, stable in the long term, polymerizable thermally and by radiatiion, by mechanism giving rise to free radicals, with a very low water (less than 1%) and volatile solvent content, containing silica, a silane, and a multifunctional acrylic monomer, in which the silica is in the form of indivualized particles with an average diameter with the range 9 amd 100 nm, not interconnected by siloxane bonds, the silane is a vinyl silane with the formula (I)

Abstract: The invention relates to thermoplastic polyolefin compositions having enhanced surface durability and products thereof which include a thermoplastic polyolefin base component at least one radiation-crosslinkable component present in an amount sufficient to enhance the surface durability of the thermoplastic polyolefin component when radiation-cured and at least one photoinitiator present in an amount sufficient to initiate crosslinking of the radiation-crosslinkable component upon exposure of the thermoplastic polyolefin composition to radiation.

Abstract: The invention relates to a dental material with at least one polymerizable binder and at least one filler containing a redox-initiator system for the radical polymerization, which comprises an initiator and an activator. The material is characterized in that the filler contains a homogeneous mixture of a first part of the filler, which is mixed with the initiator, a second part of the filler, which is mixed with the activator, and a third part of the filler, which does not contain a component of the initiator system. The materials are particularly suitable as cements and filling materials.

Abstract: The present invention is directed to silicone formulations which are capable of being rapidly cured to tough elastomeric materials through exposure to UV radiation. The cured products demonstrate high resistance to flammability and combustibility.

Abstract: A radiation curable, flexible, paintable composition produced from epoxy compounds and one or more polyol(s) has enhanced durability, thick and thin film adhesion, resistance to mold growth and dimensional changes while reducing solvent emissions. The composition can reduce, if not eliminate, runs and drips during the thermal bake cycles which are associated with using conventional compositions in automotive applications.

Abstract: A curable composition comprising a) a curable epoxy resin, a thermoplastic ethylene-vinyl acetate copolymer resin, and an effective amount of a photocatalyst for the curable epoxy resin, wherein the composition is free from hydrocarbon polyolefins and wherein the sum of a) and b) is 100 weight percent.

Abstract: A radiation curable resin composition comprising (A) a first linear (meth)acryloyl and aromatic group-containing compound, (B) a second branched (meth)acryloyl group-containing compound, (C) a radiation polymerization initiator, and (D) silica particles having a secondary average particle diameter of 0.5 to 5 &mgr;m. The composition is suitable for use as a printable heat-resistant protective coat which is used for information recording media such as thermosensible recording cards and thermosensible photographic printing paper.

Abstract: Photoinitiator combinations comprising at least one compound of formula (I) R1 is C1-C4alkyl, C1-C4alkoxy or halogen; R2 is hydrogen, C1-C4alkyl, C1-C4alkoxy or halogen; R3 is, for example, C1-C20alkyl, cyclopentyl, cyclohexyl, phenyl-C1-C4alkyl, naphthyl or biphenylyl or an O—, S— or N-containing 5- or 6-membered heterocyclic ring; and at least one compound of formula (II) R1 and R2 are as defined above; R9 is, for example, C1-C20alkyl, cyclopentyl, cyclohexyl, phenyl-C1-C4alkyl, naphthyl, biphenylyl or an O—, S— or N-containing 5- or 6-membered heterocyclic ring; and R10 is, for example, C1-C20alkyl, C2-C20alkyl interrupted by one or more O atoms, cyclopentyl, cyclohexyl, phenyl-C1-C4alkyl, naphthyl, biphenylyl or an O—, S— or N-containing 5- or 6-membered heterocyclic ring; are reactive photo hardeners causing only a low degree of yellowing in the cured substrates.

Abstract: The present invention is directed to polymerizable dental compositions containing a) 3 to 80 wt. % of cycloaliphatic epoxides; b) 0 to 80 wt. % of an epoxide or a mixture of epoxides which are different from a); c) 3 to 85 wt. % of a filer material; d) 0.01 to 25 wt. % of initiators, inhibitors and/or accelerators; e) 0 to 25 wt. % of auxiliary agents, the individual percentages of which are in relation to the total weight. The new polymerizable agents are particularly suited as dental material.

Abstract: A radiation-polymerizable composition contains at least one radiation curable acrylate resin oligomer prepared by reacting an alkoxylated polyol with a first acid component which includes an ethylenically unsaturated carboxylic acid; and a rheology modifier prepared by reacting a diepoxide with a second acid component which includes an ethylenically unsaturated carboxylic acid or reactive derivative thereof in the presence of a polyamide based on a polymerized fatty acid. The ethylenically unsaturated carboxylic acids of the first and second acid components are preferably acrylic acid or methacrylic acids. The diepoxide is preferably a diglycidyl ether such as bisphenol A. Colorants such as pigments or dyes optionally may be incorporated into the composition to form a printing ink which is curable by ultraviolet (UV) or electron beam radiation.

Abstract: The present invention relates to; resin molded articles having on one side of the resin substrate thereof, such as polycarbonate, a scuff resistant organic hard coat layer and on the other surface of the substrate an antifogging organic hard coat layer; resin shaped articles such as into helmet shields, goggles, and the like, in which the organic hard coat layer will not peel off the substrate when molded into a curve-shaped article having a radius of curvature of 50 mm or less and which will cause no optical distortions; a process for the manufacture thereof; and the covering materials for forming each hard coat layer.

Abstract: The present invention provides processes by which a polymeric hydrogel can be securely adhered to a substrate to form a hydrogel laminate with greatly improved delamination resistance. The laminate is formed by casting onto a polymeric adhesive-coated substrate an aqueous solution of hydrophilic polymer, then exposing this composite to ionizing radiation which cross-links the hydrophilic polymer to form a hydrogel and also induces copolymerization of the hydrophilic polymer and the adhesive polymer.

Abstract: Disclosed is a UV-curable transfer ink which can be cured by UV and used to emboss a precise and clear pattern on a substrate. It comprises 20-40% by weight of a UV-reactive ink, 20-40% by weight of an acrylic copolymer, 4-6% by weight of an ethylene vinyl acetate copolymer, 25-35% by weight of an organic solvent and 0.5-5% by weight of a bulking agent. A printing sheet is also provided, on which the transfer ink is printed in a predetermined pattern. An embossed pattern is obtained by applying the sheet to a substrate, exposing it to UV to cure the printed transfer ink, releasing the printing sheet to leave the cured transfer ink on the substrate, and etching the substrate.

Abstract: A photocurable paint composition for road markings is disclosed, comprising (A) a compound having an ethylenically unsaturated group, (B) a filler, (C) a cationic dye represented by formula (1): D+&Circlesolid;A1−  (1) (wherein D+ represents a cation having an absorption maximum wavelength in the wavelength region of from 400 to 1,200 nm, and A1− represents an optional anion), (D) a quaternary organic borate-type sensitizer represented by formula (2): (wherein R1, R2, R3 and R4 each independently represents an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group or a halogen atom, and Z+ represents an optional cation) and (E) an ultraviolet radical polymerization initiator capable of generating a radical upon absorption of light at a wavelength of 400 nm or less, or additionally comprising (F) glass beads.

Abstract: Disclosed is a photo-curable composition comprising the following components (A) to (C): (A) hydrolyzable silane compound represented by the general formula (1) or a hydrolyzate thereof: (R1)pSi(X)4−p (1) wherein R1 is a non-hydrolyzable organic group having 1 to 12 carbon atoms, X is a hydrolyzable group, and p is an integer of 0 to 3; (B) photo acid generator; and (C) dehydrating agent. By such constitution, it is possible to provide a photo-curable composition which has a rapid photo-curable rate, is excellent in characteristics such as storage stability, heat resistance, weather-ability, scratch resistance and the like, and is applicable to base materials having low heat resistance such as plastics, as well as a cured product obtained therefrom.

Abstract: A resin composition for forming a three-dimensional object by optical stereolithography, which contains 5 to 65 vol % of aluminum oxide fine particles having an average particle diameter of 3 to 70 &mgr;m and 5 to 30 vol % of whiskers having a diameter of 0.3 to 1 &mgr;m, a length of 10 to 70 &mgr;m and an aspect ratio of 10 to 100, the total content of the aluminum oxide fine particles and the whiskers being 10 to 70 vol %. According to the resin composition for forming a three-dimensional object by optical stereolithography, a high-quality three-dimensional object by optical stereolithography that has high heat resistance with a high heat distortion temperature and high rigidity with a high flexural modulus and that is free from a dimensional change on account of a low linear thermal expansion coefficient even when temperature varies can be obtained by optical stereolithography with high dimensional accuracy.

Abstract: To provide a photosensitive paste that permits pattern formation with a high aspect ratio and a high accuracy and to provide a plasma display including the photosensitive paste, by using a photosensitive paste that includes, as essential components, an inorganic particles and an organic component that contains a photosensitive compound with the difference between the average refractive index of the organic component and the average refractive index of the inorganic particles being 0.1 or less.

Abstract: A process for preparation of ceramic objects which comprises: (a) applying a layer of a high-solids photocurable ceramic composition, to a substrate, the composition comprising: (1) at least 10 percent by volume of water; (2) at least 0.05 percent by weight of photocurable compounds which are soluble or dispersible in water; and (3) at least 45 volume percent dispersed ceramic particles; and (b) subjecting the composition to sufficient ultraviolet radiation to react the compounds or polymers sufficiently to form a layer of the photocurable compounds or polymers, which is water-insoluble and non-dispersible in water, having the ceramic particles dispersed therein.

Abstract: Zirconium oxide nanoparticles having at least some surface acid sites functionalized with a silanating agent and at least some surface acid sites finctionalized with zirconate or a zircoaluminate. The nanoparticles are useful in composites comprising photopolymerizable alkene matrix monomers, and are primarily suitable for dental and medical restoration.

Abstract: The invention provides an insulating paste, comprising: an organic vehicle containing an organic binder, a photo-polymerization initiator and a photosetting monomer; and a silicate glass powder having a softening point in a range of about 700° C. to 1,050° C. and having an average particle size in a range of about 0.1 to 5.0 &mgr;m, said silicate glass powder being dispersed into said organic vehicle. Preferably, the silicate glass powder of the above insulating paste comprises a composition represented by xSiO2—yB203—zK2O where x+y+z is 100 parts by weight and the values z, y and z are on lines or within a region enclosed by lines passing through four points A(65, 35, 0), B(65, 20, 15), C(85, 0, 15) and D(85, 15, 0) on a ternary diagram thereof.

Abstract: The instant invention pertains to a composition that can form silica thin films, wherein said composition performs well as a substrate planarizing coating when applied to a substrate and can be converted by exposure to high-energy radiation into silica thin film with an excellent electrical insulating performance. The composition for the formation of silica thin films comprises (A) a hydrogen silsesquioxane resin that contains at least 45 weight % hydrogen silsesquioxane resin with a molecular weight no greater than 1,500; and (B) solvent. A silica thin film is produced by evaporating the solvent (B), and then converting at least a portion of the hydrogen silsesquioxane resin (A) to silica by exposing the surface of the said substrate to high-energy radiation. The preferred substrate is a semiconductor substrate having at least one electrically conductive layer.

Abstract: Photocurable, addition polymerizable compositions contain an epoxy resin and a photoinitiator system containing (a) an epoxy resin, (b) a hydroxyl containing material and (c) a photoinitiator system comprising: (i) an iodonium salt; (ii) a visible light sensitizer; and (iii) an electron donor compound, wherein the photoinitiator system has a photoinduced potential of at least about 100 mV relative to a standard solution of 2.9×10−5 moles/g diphenyl iodonium hexafluoroantimonate and 1.5×10−5 moles/g camphorquinone in 2-butanone. The compositions cure on exposure to light in the visible spectrum and are useful in a variety of applications, including dental adhesives and composites.

Abstract: Disclosed herein is a game ball, such as a golf ball, having an indicia formed from a UV curable ink containing aluminum trihydroxide (ATH) filler. The ATH improves pad transfer of the ink. An ink composition suitable for pad printing, and a method for applying an indicia to a game ball also are disclosed. The UV curable ink has excellent pad transfer properties, and good durability.

Abstract: The present invention relates to a radiation-curable binder BM consisting of a copolymer which is composed of: A) from 80 to 99% by weight of a hydroxyl-containing polyether acrylate and/or polyester acrylate A), which optionally contains a mono-, di- and/or polyamine AA) as adduct, and of B) from 1 to 20% by weight of benzophenonetetracarboxylic acid, its anhydrides and/or its esters. The invention additionally relates to processes for the preparation of the binder BM and to the use of the binders BM in radiation-curable coating compositions.

Abstract: A UV curable, flexible, paintable composition is disclosed. The disclosed composition has enhanced durability, thick and thin film adhesion, resistance to mold growth and dimensional changes while reducing solvent emissions. The disclosed composition reduces, if not eliminates, runs and drips during the thermal bake cycles which are associated with using conventional compositions in automotive applications.

Abstract: New betaketosulfonic derivatives, the process for their preparation, the photopolymerizable systems containing the same and their application as polymerization photoinitiators for inks, and particularly for inks having high content of pigments are described.

Abstract: In a first aspect, a method for treating hard tissue that includes: (a) applying to hard tissue a composition that includes a cationically active functional group, a free radically active functional group, and a polymerization initiator capable of initiating free radical polymerization, where the number of moles of cationically active functional groups per gram of composition is no greater than about 0.0075; and (b) exposing the composition to polymerization conditions to form an adhesive bonded to the hard tissue.

Abstract: Disclosed herein is a game ball, such as a golf ball, having an indicia formed from a UV curable ink containing aluminum trihydroxide (ATH) filler. The ATH improves pad transfer of the ink. An ink composition suitable for pad printing, and a method for applying an indicia to a game ball also are disclosed. The UV curable ink has excellent pad transfer properties, and good durability.

Abstract: A photocuring resin composition for orthodontics is disclosed, comprising:(a) 5.about.50% by weight of a urethane bond-free (meth)acrylate having an average molecular weight of 100.about.300 and having at least one unsaturated double bond;(b) 10.about.60% by weight of a urethane bond-containing (meth)acrylate having an average molecular weight of 300.about.5,000 and having at least one unsaturated double bond;(c) 5.about.30% by weight of a crosslinked polyurethane powder;(d) 10.about.50% by weight of an inorganic filler; and(e) 0.03.about.3% by weight of a photocuring initiator.

Abstract: The present invention provides a polymerizable printing ink. The ink includes a polar suspending medium in which a plurality of polymer microspheres are suspended. At least one surfactant is dissolved in the suspending medium, and a monomer is positioned in the ink such that polymerization of the monomer after the application of the ink to a substrate will hold the microspheres in fixed relations to one another. The microspheres have a chemically associated coloring agent to provide the ink with color. The ink may include a polymerization initiator, such as a photoinitiator, to cause the film to polymerize upon the application of a form of energy, such as ultraviolet light. The invention also provides methods for making and using the ink, and for adding a coloring agent to a plurality of polymer microspheres.

Abstract: A novel method for producing thick composite parts based upon photopolymerizable compositions is disclosed. Also disclosed are novel methods for encapsulation of microelectronic devices based upon novel photopolymerizable compositions. The constituents of the photopolymerizable mixture comprise a monomer or monomers capable of polymerizing by free radical or cationic mechanisms, and a photoinitiator system which possesses an absorbance characteristic which is effectively reduced, or self-eliminating, upon initiation of the polymerization reaction. Parts having thicknesses up to 2 cm and thicker for varying end use applications are made by photopolymerizing such compositions. In addition, using such compositions composite parts can be made using a reinforcement material such as a glass fiber mat present in an amount by weight of from about 5 to about 70%.

Abstract: An ultraviolet curable clearcoat composition comprising (exclusive of any solvent present): (a) about 30% to about 90% by weight of an acrylated aliphatic urethane having a molecular weight of about 1200 to 2600 and formed by the reaction of a multifunctional acrylate with a molecular weight of between about 110 and about 500 with an aliphatic urethane based on a polyether and having a molecular weight of about 800 to about 2200; (b) about 15% to about 70% by weight of a multifunctional acrylate having a molecular weight of about 170 to about 1000 and containing at least two polymerizable unsaturated groups per molecule; and (c) a photopolymerization initiator and/or sensitizer. Also described are preferred processes and clearcoated articles involving preferred clearcoat compositions.

Abstract: A coating composition which is comprised of an emulsion of a silicone resin, typically a water-insoluble, silanol group-bearing silicone resin dispersed in water, and contains photocatalyst particles, typically titanium oxide forms a hydrophilic film having a water-drop contact angle of no more than 60.degree. when irradiated with UV-containing light. The composition eliminates the use of organic solvents and has excellent dispersion and storage stability. Films obtained by applying this coating composition to the surface of substrates have excellent weathering resistance and antifouling properties due to a self-cleaning effect arising from the photocatalytic action of the particles.