HEAT CURABLE RESIN COMPOSITON

摘要

[MEANS FOR SOLVING PROBLEMS] A heat curable resin composition comprising (A) a resin containing two or more carboxyl groups and having a polyurethane structure, (B) a strongly basic nitrogen-containing heterocyclic compound having a pKa value of 10.0 to 14.0 as a curing accelerator, and (C) a curing agent. A cured product of the heat curable resin composition is used as an insulating protective film, for example, for printed wiring boards, flexible printed wiring boards, and chip-on films. The heat curable resin composition has improved low-temperature curability and instantaneous curability, can realize tack-free properties, can simultaneously realize low warpage properties and electric insulating properties, does not contaminate a curing oven and the like with an out gas during heating, has a satisfactory pot life, can form excellent cured products and insulating protective films, and can form solder resists and insulating protective films at low cost with good productivity. Further, this composition can be utilized to supply electronic components to which excellent properties have been imparted.