Photosensitive resin composition solution

A photosensitive resin composition solution for formation of a printed wiring board permanent mask to be coated on a substrate to be coated according to the curtain flow coating method or the roll coating method, comprising

• (A) an oligomer having at least one epoxy group and at least one polymerizable vinyl group in the side chain,
• (B) a photopolymerization initiator,
• (C) an epoxy resin curing agent,
• (D) a filler and
• (E) a solvent capable of dissolving the oligomer, characterized in that
• (1) said solvent (E) contains 10 to 20% by weight of at least one low boiling point solvent selected from the group consisting of methanol, ethanol, methyl ethyl ketone, acetone and ethyl acetate based on the total amount of the solvent, and
• (2) said composition solution has a viscosity of 100 mPas to 200 mPas at 25.degree. C.;
• and
• (3) said oligomer having an epoxy group and a polymerizable vinyl group in the side chain is an oligomer obtained by reacting isocyanatoethyl methacrylate with an unsaturated compound, which is obtained by addition reaction of a compound having at least two epoxy groups and an unsaturated carboxylic acid at an acid equivalent/-epoxy equivalent ratio in the range of 0.1 to 0.98, at a ratio relative to the hydroxyl group of the unsaturated compound of an isocyanate equivalent/hydroxyl group equivalent ratio in the range of 0.1 to 1.2.