Patent ID: 7691459

Claim:
An optical, antireflection film comprising: a transparent support; and at least one optical functional layer comprising a low refractive index layer, wherein the low refractive index layer comprises a copolymer comprising a repeating unit derived from a fluorine-containing vinyl monomer and a repeating unit having a (meth)acryloyl group or a hydroxyl group in a side chain, wherein at least one of said at least one optical functional layer is formed by using an inorganic fine particle-containing composition comprising: a silylation-treated inorganic oxide fine particle, which comprises 1.4 or more silyl groups per a surface area of 1 nm 2 of the inorganic oxide fine particle, wherein the silylation-treated inorganic oxide fine particle comprises at least one oxide selected from the group consisting of silicon dioxide, tin oxide, indium oxide, zinc oxide and zirconium oxide, wherein the silylation-treated inorganic oxide fine particle is an inorganic oxide fine particle silylation-treated with a compound represented by Formula (II): wherein R 1 represents a hydrogen atom, a methyl group, a methoxy group, an alkoxycarbonyl group, a cyano group, a fluorine atom or a chlorine atom; Y represents a single bond, an ester group, an amido group, an ether group or a urea group; L represents a divalent linking chain; n represents 0 or 1, and when a plurality of X's are present, the plurality of X's may be the same or different; R 10 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; and X represents a hydroxyl group or a hydrolyzable group, wherein the transparent support is a transparent film obtained from an inorganic fine particle-containing composition comprising a silylation-treated inorganic oxide fine particle, which comprises 1.4 or more silyl groups per a surface area of 1 nm 2 of the inorganic oxide fine particle.