Interlaminar insulating adhesive for multilayer printed circuit board

摘要

In order to provide a multilayer printed circuit board having a fine pitch circuit, the interlaminar insulating adhesive used therein must have heat resistance and low thermal expansion coefficient so that required accuracy can be obtained during circuit formation and mounting of components. Therefore, the present invention aims at providing a multilayer printed circuit board which uses an interlaminar insulating adhesive superior in heat resistance and low in thermal expansion coefficient and wherein the insulating adhesive layer has a small variation in thickness between circuit layers. That is, the present invention lies in an interlaminar insulating adhesive for multilayer printed circuit board containing the following components as essential components: (a) a sulfur-containing thermoplastic resin having a weight-average molecular weight of 10<3> to 10<5>, (b) a sulfur-containing epoxy or phenoxy resin having a weight-average molecular weight of 10<3> to 10<5>, (c) a multifunctional epoxy resin having an epoxy equivalent of 500 or less, and (d) an epoxy-curing agent.et