Transparent film

Abstract

A transparent film is capable of suppressing discoloration caused by heat, while retaining high transparency and high glass transition temperature. The transparent film includes a glass fiber substrate made of glass fibers and impregnated with a resin composition in which a high refractive resin (a transparent resin) having refractive index higher than the glass fiber is mixed with a low refractive resin (a second transparent resin) having a refractive index lower than the glass fiber to have a resultant refractive index approximate to that of the glass fiber when cured. The high refractive resin has a 3 or more-functional epoxy resin expressed by the following formula: wherein R1 is a hydrogen atom or methyl group, R2 is a 2-valent organic group, and R3 to R10 are respectively ones selected from a group consisting of a hydrogen atom, a substituent group, and a molecular chain containing epoxy group.

Dependencies are inferred from the claim text.