Ultraviolet curable resin composition and photo solder resist ink including the same

Abstract

An ultraviolet curable resin composition comprises (A) an ultraviolet curable resin obtained by reacting an epoxy group containing polymer (a), which is prepared by polymerizing an ethylenically unsaturated monomer component including an ethylenically unsaturated monomer (i) having an epoxy group, with an ethylenically unsaturated monomer (b) having a carboxyl group, and then reacting a resultant intermediate product with a saturated or unsaturated polybasic acid anhydride (c); (B) an epoxy compound having at least two epoxy groups in molecule; (C) a photopolymerization initiator; and (D) a diluent The ultraviolet curable resin includes 0.3 to 10 mol of a polymerizable unsaturated group in 1 kg thereof. A photo solder resist ink containing this resin composition has the capability of providing a permanent film with excellent flexibility and solder heat resistance, and is preferably used to manufacture flexible printed circuit boards.

Dependencies are inferred from the claim text.