SOLID FILM LUBRICANT LAYER IN GLASS MOLDS NON-COLLOIDAL GRAPHITE LUBRICANT LAYER IN GLASS MOLDS

摘要

In methods for forming glass articles wherein hot formable glass is first formed into a parison, or blank, which is formed into the final glass article in a blow mold and wherein there is no relative rotation of the glass and the molds in the forming operation; the improvement resides in providing the cavity-defining surface of the blank mold with a layer, or coating, of a solid film lubricant or glass release agent which essentially comprises a non-colloidal lubricating graphite dispersed in a thermoset, cured, hard organopolysiloxane binder. The layer, or coating, is formed by applying a dispersion of graphite in an organic solvent solution of a further-curable, thermosettable, solvent soluble, organopolysiloxane onto the cavity defining surface of the blank mold and then curing said organopolysiloxane to a thermoset hard condition.