abstract |
There is provided a photosensitive thermosetting resin composition of an alkali development type from which it is possible to form a coating film that is halogen-free yet has high-level flame retardancy, has a superior low warpage property after it is cured, is excellent in plasticity, resolution, soldering heat resistance, chemical resistance, and the like, and a flexible printed circuit board using the same. There is provided a photosensitive thermosetting resin composition of an alkali development type and a flexible printed circuit board using the same, the photosensitive thermosetting resin composition including: (A) a resin component having a (meth)acryloyl group and a carboxyl group in one molecule and soluble in a dilute alkali solution; (B) a phosphorus-containing epoxy thermosetting resin component; (C) a photopolymerization initiator; (D) an organophosphorus compound; and (E) a diluent, and having excellent performance in all the properties comparable to those of conventional photosensitive thermosetting resin compositions using brominated epoxy resin and a halogen-based flame retardant, and having an excellent property of not generating hydrogen bromide which has been a problem at the time of the combustion. |