New heat resistant solventless varnish ?10 resin? (part II)

The research and development of organic heat resistant materials has made a great progress especially in the field of solvent type varnishes. For example, polyimide, polybenzimidazole, polydiphenylether, and silicone have been developed so far. However, solventless varnishes that can resist high temperatures have not been developed yet, because it is very difficult to give high temperature heat resistant properties to cured resins which have a low viscosity before curing. Epoxy resins are now widely used as solventless varnishes, however, they cannot be used at temperatures above 180?C.