Photosensitive epoxy resin composition for formation of optical waveguide, photosensitive film for formation of optical waveguide, optical waveguide produced by using the epoxy resin composition or the photosensitive film, and hybrid flexible printed wiring board for optical/electrical transmission

Abstract

A photosensitive epoxy resin composition for formation of an optical waveguide is provided, which contains an epoxy resin component and a photo-cationic polymerization initiator, wherein the epoxy resin component includes: (a) a solid bisphenol-A epoxy resin having a softening point of not higher than 105° C.; (b) a solid polyfunctional aliphatic epoxy resin having a softening point of not higher than 105° C.; and (c) a liquid long-chain bifunctional semi-aliphatic epoxy resin, wherein the epoxy resin (a) is present in a proportion of 60 to 70 wt. % based on the weight of the epoxy resin component, wherein the epoxy resin (b) is present in a proportion of 20 to 35 wt. % based on the weight of the epoxy resin component, wherein the epoxy resin (c) is present in a proportion of 5 to 10 wt. % based on the weight of the epoxy resin component.

Dependencies are inferred from the claim text.