Abstract: A method of preventing or reducing fogging of a surface of a composite when subjected to humid conditions includes providing a composite with a surface. The composite includes a substrate and a photocatalytic surface layer. The photocatalytic surface layer includes a photocatalyst. The method further includes subjecting the photocatalyst to photoexcitation to render the surface of the composite hydrophilic, wherein, after the photoexcitation, the surface of the composite has a water wettability of less than 10° in terms of the contact angle with water. The method further includes subjecting the composite to humidity that is sufficient to induce fogging of the substrate if the photocatalytic surface layer were absent.

Abstract: A method of preventing or reducing fogging of a surface of a composite when subjected to humid conditions includes providing a composite with a surface. The composite includes a substrate and a photocatalytic surface layer. The photocatalytic surface layer includes a photocatalyst. The method further includes subjecting the photocatalyst to photoexcitation to render the surface of the composite hydrophilic, wherein, after the photoexcitation, the surface of the composite has a water wettability of less than 10° in terms of the contact angle with water. The method further includes subjecting the composite to humidity that is sufficient to induce fogging of the substrate if the photocatalytic surface layer were absent.

Abstract: The surface of a substrate is coated with an abrasion-resistant photocatalytic coating comprised of a semiconductor photocatalyst. upon irradiation by a light having a wavelength of an energy higher than the bandgap energy of the photocatalyst, water is chemisorbed onto the surface in the form of hydroxyl groups (OH−) whereby the surface of the photocatalytic coating is rendered highly hydrophilic. In certain embodiments, the surface of a mirror, lens, or windowpane is coated with the photocatalytic coating to exhibit a high degree of antifogging function. In another embodiment, an article or product coated with the photocatalytic coating is disposed outdoors and the highly hydrophilic surface thereof is self-cleaned as it is subjected to rainfall. In a still another embodiment, an article is coated with the photocatalytic coating and, when the article is soaked in, rinsed by or wetted with water, fatty dirt and contaminants are readily released without resort to a detergent.

Abstract: The surface of a substrate is coated with an abrasion-resistant photocatalytic coating comprised of a semiconductor photocatalyst. Upon irradiation by a light having a wavelength of an energy higher than the bandgap energy of the photocatalyst, water is chemisorbed onto the surface in the form of hydroxyl groups (OH−) whereby the surface of the photocatalytic coating is rendered highly hydrophilic. In certain embodiments, the surface of a mirror, lens, or windowpane is coated with the photocatalytic coating to exhibit a high degree of antifogging function. In another embodiment, an article or product coated with the photocatalytic coating is disposed outdoors and the highly hydrophilic surface thereof is self-cleaned as it is subjected to rainfall. In a still another embodiment, an article is coated with the photocatalytic coating and, when the article is soaked in, rinsed by or wetted with water, fatty dirt and contaminants are readily released without resort to a detergent.

Abstract: Multi-functional materials which have a photocatalytic layer with a photocatalytic function disposed on the surface of a base through a binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer are joined together by a surface energy or solid-state sintering. The photocatalytic layer may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles.

Abstract: Multi-functional materials which have a photocatalytic layer with a photocatalytic function disposed on the surface of a base through a binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer are joined together by a surface energy or solid-state sintering. The photocatalytic layer may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles.

Abstract: Multi-functional materials which have a photocatalytic layer with a photocatalytic function disposed on the surface of a base through an amorphous binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer are joined together by a surface energy or solid-state sintering. The photocatalytic layer may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles. A lower layer of the photocatalytic layer is embedded in the binder layer such that an intermediate layer is formed between the binder layer and the photocatalytic layer, the intermediate layer including components of the binder and photocatalytic layers in varying concentrations therethrough.

Abstract: A photocatalytic functional material having an excellent photocatalytic activity even by a low temperature heat treatment and having a high mechanical strength of the surface. The photocatalytic functional material of the present invention comprises a surface layer (a photocatalytic functional layer) containing a photocatalyst, an electron trapping metal and a photodegradation-resistant matrix. Though the major proportion of the photocatalyst (TiO2 particles, and the like) in the photocatalytic functional layer are covered with the photodegradation-resistant matrix (a thermosetting resin, and the like), the electron-trapping metal effectively traps the electrons generated by the photocatalytic reaction, retains positive holes and generates active oxygen species, so that the photocatalytic function such as deodorant and antimicrobial activities can be fully exhibited.

Abstract: A method for hydrophilifying the surface of a substrate by taking advantage of photocatalytic action. The substrate has a photocatalytic titania coating (10). The surface of the photocatalytic coating (10) bears the solid acid that increases a hydrogen bond component (.gamma..sub.S.sup.h) in the surface energy in the solid/gas interface of the coating. Photoexcitation of the photocatalyst enhances the hydrogen bond component (.gamma..sub.S.sup.h) in the surface energy of the photocatalytic coating (10), accelerating the physical adsorption of molecules of water in the atmosphere through a hydrogen bond (16) onto hydrogen atoms in a terminal OH group (12), bonded to a titanium atom, and a bridge OH group (14) on the surface of the coating. This results in the formation of a high density, physically adsorbed water layer (18) on the surface of the photocatalytic coating (10), thus permitting the surface of the substrate to be easily hydrophilified.

Abstract: Multi-functional materials which have a photocatalytic layer with a photocatalytic function disposed on the surface of a base through a binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer are joined together by a surface energy or solid-state sintering. The photocatalytic layer may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles.

Abstract: The surface of a substrate is coated with an abrasion-resistant photocatalytic coating comprised of a semiconductor photocatalyst. Upon irradiation by a light having a wavelength of an energy higher than the bandgap energy of the photocatalyst, water is chemisorbed onto the surface in the form of hydroxyl groups (OH.sup.--) whereby the surface of the photocatalytic coating is rendered highly hydrophilic. In certain embodiments, the surface of a mirror, lens, or windowpane is coated with the photocatalytic coating to exhibit a high degree of antifogging function. In another embodiment, an article or product coated with the photocatalytic coating is disposed outdoors and the highly hydrophilic surface thereof is self-cleaned as it is subjected to rainfall. In a still another embodiment, an article is coated with the photocatalytic coating and, when the article is soaked in, rinsed by or wetted with water, fatty dirt and contaminants are readily released without resort to a detergent.

Abstract: Multi-functional materials are classified into those which have a photocatalytic layer 2 with a photocatalytic function directly disposed on the surface of a base 1 and those which have a photocatalytic layer 2 with a photocatalytic function disposed on the surface of a base 1 through a binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer 2 are joined together by a surface energy or solid-state sintering. The photocatalytic layer 2 may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles.

Abstract: By curing a curable organopolysiloxane composition comprising an organopolysiloxane and photocatalytic particles, typically of titanium oxide, there is obtained a rubber member. A surface of the rubber member can be rendered hydrophilic or non-staining by irradiating UV radiation to the surface. The rubber member is thus useful as a building seal, coating and gasket.

Abstract: A photocatalytic coating composition comprising (A) a coat-forming element capable of forming a coating of silicone resin when cured and (B) a photocatalyst dispersed therein. The coat-forming element is comprised of an organopolysiloxane having a monovalent organic C.sub.1 -C.sub.18 group and a C.sub.1 -C.sub.4 alkoxy group. The coating composition is applied to an article and cured to form a silicone coating thereon. When the coating is exposed to light, typically UV, the photocatalyst is excited to provide photocatalysis permitting organic groups attached to silicon atoms of silicone molecules at the coating surface to be replaced by hydroxyl groups in the presence of water, thereby rendering the coating surface hydrophilic. Thereafter, the coating maintains water affinity semi-eternally and has improved weather resistance.