PHOTOSENSITIVE RESIN COMPOSITION, SOLDER RESIST COMPRISING THE SAME, COVER LAY FILM, AND PRINTED CIRCUIT BOARD

摘要

A photosensitive resin composition excellent in heat resistance, processability and adhesion; a solder resist comprising the composition; and a cover lay film and printed circuit board obtained from or with these. The cover lay film has excellent processability and adhesion at relatively low temperatures while retaining sufficient mechanical strength, gives a cured film having a low modulus, and is suitable for use in producing printed boards or hard disks. The solder resist is soluble, can be laminated at a temperature not higher than 150 DEG C, and can be applied directly to an FPC without through an adhesive. The cover lay film is excellent in various properties including heat resistance and causes little warpage when laminated to an FPC. The photosensitive resin composition comprises as essential ingredients (A) a soluble polyimide which is soluble in solvents having a boiling point of 120 DEG C or lower and (B) a compound having one or more aromatic rings and two or more double bonds per molecule, wherein the soluble polyimide is one obtained at least from an acid dianhydride having one to six aromatic rings or alicyclic acid dianhydride and/or a diamine having one to six aromatic rings. The solder resist, cover lay film, etc. are excellent in heat resistance and mechanical properties and do not damage the substrates because they can be laminated at a relatively low temperature.