Impregnating coating layer for insulating sheets

Abstract

The present invention relates to an insulating sheet of a nonwoven sheet, for example a sheet comprising aramid fiber, comprising 15 to 80 percent by weight of a crystalline silicate mineral powder, for example a mica powder, the nonwoven sheet impregnated with a coating of an impregnating resin based on acrylate derivatives, which is suitable for increasing the compactness of the insulating sheet and for preventing the silicate mineral powder from detaching from the nonwoven sheet during use. The impregnating resin also comprises an organic solvent, which is capable of reducing the viscosity thereof and of promoting its deep penetration into the sheet. In addition, the impregnating resin comprises a UV polymerization photoinitiator which is suitable for curing the resin, only after said resin has been applied to the sheet and has penetrated deeply therein. The invention also describes the method for impregnating the insulating sheets.

Dependencies are inferred from the claim text.