Monolayer film and hydrophilic material comprising the same

Abstract

The invention provides monolayer films which not only have hydrophilicity and are excellent in such properties as antifogging properties, antifouling properties, antistatic properties and anti-condensation properties but also tend to exhibit excellent transparency even with a large film thickness and excellent scratch resistance, as well as stacks having the monolayer film. The monolayer film is obtained by preparing a mixture including a monomer composition and a solvent, the monomer composition including a specific monomer and a polyvalent monomer having two or more (meth)acryloyl groups and being free of sulfonic group, carboxyl group and phosphoric group in a specific molar ratio, the solvent having a specific solubility parameter σ; applying the mixture onto a substrate and removing at least part of the solvent; and polymerizing the monomer composition to produce a monolayer film having at least one anionic hydrophilic group selected from a sulfonic group, a carboxyl group and a phosphoric group and a specific anion concentration ratio (Sa/Da) of the anion concentration (Sa) at the outer surface to the anion concentration (Da) at the middle point between the inner surface in contact with the substrate and the outer surface.