| abstract |
The present invention is a flame-retardant photo-curable resin composition, a dry film and a cured product thereof, which are capable of forming a cured film having a low environmental load, excellent flame retardancy and storage stability, and a flexible, non-halogen composition. Provided is a printed wiring board on which a flame-retardant cured film such as a resist is formed.n n n The flame-retardant photocurable resin composition contains a carboxyl group-containing resin, a soluble phosphazene compound soluble in 5% by weight or more of the carboxyl group-containing resin or its varnish, and a photopolymerization initiator. Preferably, the carboxyl group-containing resin is a carboxyl group-containing polyurethane resin. Suitably it further contains a photopolymerizable monomer, or further contains a thermosetting resin. Such a flame-retardant photocurable resin composition, especially the photocurable thermosetting resin composition containing a thermosetting resin, can be used suitably as a soldering resist. |