| abstract |
A solder resist composition having excellent developability and through-hole developability while maintaining solder heat resistance, electroless gold plating resistance, and electrical characteristics equal to or higher than those of conventional solder resists, its dry film and curing Products and printed wiring boards having cured films thereof. A solder resist composition includes (A) a photosensitive resin having a lactic acid-based polyester structure and having at least one ethylenically unsaturated group in the molecule, (B) a photopolymerization initiator, and (C). Contains a carboxyl group-containing resin. In another embodiment, (A ′) a carboxyl group-containing photosensitive resin containing a structure represented by a specific formula and having at least one ethylenically unsaturated group in the molecule, and (B) a photopolymerization initiator To do. Preferably, it further contains a thermosetting component (D). [Selection figure] None |