Laminated optical film, method of producing laminated optical film, optical element, and image display

A laminated optical film comprising:

• a void-provided layer;
• a resin film;
• and
• a cover layer, wherein:
• the void-provided layer is formed on the resin film,
• the cover layer having a thickness of from 50 to 10,000 nm is formed directly on the void-provided layer,
• the void-provided layer has a contact angle with water of 90° or more, and a proportion of void spaces of 30 vol % or more such that the void spaces of the void-provided layer are not filled with the cover layer,
• the void-provided layer is a porous body in which microporous particles are chemically bonded to each other,
• the cover layer is porous with a proportion of void spaces of 10 vol % or less,
• the cover layer contains a water-soluble polymer, and a water-soluble silane crosslinked product formed from at least one of monomers and oligomers of water-soluble alkoxysilane, said monomers and/or oligomers of water-soluble alkoxysilane of the cover layer chemically bonded to the microporous particles of the void-provided layer, and
• after the steel wool test on the cover layer (φ25 mm, 100 g (load)×10 (reciprocation)), no scratch was found by visual observation.