| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultraviolet curing photo solder resist ink which is used for forming a permanent protective film small in halogen content. SOLUTION: This photo solder resist ink contains (A) ultraviolet curing resin possessed of an unsaturated ethylene and a carboxyl group as side chains, (B) a multifunctional epoxy compound, (C) organic coloring pigment, (D) a photopolymerization initiator, and (E) organic solvent, where the organic coloring pigment is selected out of organic coloring pigments which contain no halogen in their chemical structural formulas, and the halogen content of the hardened photo solder resist ink is 50 ppm or less. |
