CURABLE RESIN COMPOSITION DRY FILM COMPRISING THE COMPOSITION CURED PRODUCT AND PRINTED WIRING BOARD HAVING THE CURED PRODUCT

The present invention relates to a curable resin composition, a dry film formed from the composition, a cured product, and a printed circuit board having the cured product. The invention provides a curable resin composition which is excellent in resolution of filled spherical silica, and which is excellent in high temperature and high humidity resistance (PCT resistance) and cold cycle resistance(TCT resistance) of a cured product; a dry film formed of the composition; a cured product thereof; and a printed circuit board having the cured product. The curable resin composition of the present invention contains: (A) a carboxyl group-containing resin; (B) a photopolymerization initiator; (C) an epoxy resin; and (D) an inorganic filler as the above ( C) an epoxy resin comprising an epoxy resin having a biphenyl skeleton and an epoxy resin which is solid or semi-solid at normal temperature, and as the above (D) inorganic filler, containing spherical silica and barium sulfate The volume ratio of spherical silica to