To provide a varnish capable of forming electric insulating layers which exhibit good flame retardance, excellent electric insulating properties and scarcely change their dielectric constants, to provide the electric insulating film obtained with the varnish, and to provide a laminate having the same.
This curable varnish comprising an insulating polymer, a curing agent, a flame retardant and an organic solvent is characterized in (1) that the flame retardant is particles obtained by bringing a flame retarder into contact with a phosphorous compound soluble in the organic solvent in the organic solvent and (2) that the secondary particle diameters of the flame- retarding particles contained in the varnish are ≤30 μm. The varnish is used to form the electric insulating films to obtain the multi-layered circuit substrate.
KAWASAKI MASAFUMI
WAKIZAKA YASUHIRO
