Abstract: In a fog prevention and antireflection optical element including a first water absorption layer containing a water-absorbing polymer as its main component, a high refractive layer, and a second water absorption layer which are formed on a base in this order, an inorganic material (nd>1.70) is mixed in the water-absorbing polymer of the first water absorption layer, whereby the difference in refractive index with respect to the optical element is decreased.

Abstract: An anti-fog article is obtained by coating a substrate with an anti-fog coating material to form thereon an anti-fog coating film that is hydrophillic, moisture-absorptive, insoluble and excellent in surface hardness. The anti-fog coating material contains a polyacrylic acid compound, polyvinyl alcohol and acetylacetone, and optionally sodium silicate.

Abstract: An anti-fogging and anti-reflection optical article included a substrate, a first water-absorbing film provided on the substrate, a thin film of high refractive index provided on the first water-absorbing film, and a second water-absorbing film provided on the thin film of high refractive index. The first water-absorbing film contains a water-absorbing polymer and is provided on the substrate. The thin film of high refractive index includes a polycondensation product of a hydrolysate of a metal alkoxide, and the second water-absorbing film includes a water-absorbing polymer.

Abstract: An anti-fog article is obtained by coating a substrate with an anti-fog coating material to form thereon an anti-fog coating film that is hydrophillic, moisture-absorptive, insoluble and excellent in surface hardness. The anti-fog coating material contains a polyacrylic acid compound, polyvinyl alcohol and acetylacetone, and optionally sodium silicate.

Abstract: Disclosed herein is an anti-fogging coating material comprising at least one selected from the group consisting of an inorganic alkoxide, a hydrolysate of the inorganic alkoxide and a polycondensate of the hydrolysate of the inorganic alkoxide, a polyacrylic, and polyvinyl alcohol.

Abstract: Disclosed herein is an anti-fogging coating formed on the surface of an optical substrate, wherein the anti-fogging coating comprises a water-absorbing film and a porous film in the order near to the surface of the substrate.

Abstract: Disclosed herein is an anti-fogging coating film comprising a hydrophilic polymer and a benzophenone compound represented by a general formula (I): ##STR1## wherein X.sub.1 to X.sub.10 are the same or different from one another and are individually a radical selected from the group consisting of hydrogen, hydroxyl group, sulfonic group, carboxyl group, acyl group, ester group, ether group, hydrocarbon groups, alkoxyl groups having 1 to 6 carbon atoms, amino group, hydroxyalkyl groups and hydroxyalkoxyl groups, with the proviso that at least one of X.sub.1 to X.sub.10 is a radical selected from among the hydroxyl and sulfonic groups. Anti-fogging articles comprising a base material such as glass, plastic, metal or mirror and the anti-fogging coating film provided thereon, and a composition for forming the anti-fogging coating film are also disclosed.