IEC 60371-3-4 Ed. 1.0 b:1992, Specification for insulating materials based on mica - Part 3: Specification for individual materials - Sheet 4: ... mica paper with a B-stage epoxy resin binder

Gives requirements for materials made by combining mica paper with a single polyester film and impregnating the mica paper with an epoxy resin. The material is supplied in a flexible state for final cure after application in the form of sheets or rolls.