VERFAHREN ZUM HERSTELLEN EINER VOLLKOHLENSTOFFMEMBRANE ZUM ZWECKE DER AKUSTIKAUSRUESTUNG

A process for preparing a wholly carbonaceous integrated diaphragm for acoustic equipment use comprises blending under application of high shearing force a mixture of one or more kinds of organic high polymeric substances carbonizable on baking and powder of graphite with crystals high elastic modulus developed therein; extrusion-molding the uniformly blended and dispersed mixture through a profile extrusion die to give a core material with orientation along the direction of the extrusion and to be cut to a desired form; independently blending and sheeting under application of high shearing force the mixture with the organic powder oriented to high degree parallel to the direction of the surface of the sheet and further passing the sheet through a calendering roll to give a skin material in the form of a film or sheet; bonding said skin material on both sides of the core material by the use of such organic liquid composition that provides high yield of carbon residue on baking and then baking the resulting unitary body in an atmosphere of inert gas after subjecting it to the treatment for making insoluble and infusible.