SUBSTRATE FOR MAGNETIC RECORDING MEDIUM AND ITS PRODUCTION

摘要

PURPOSE:To overcome the difficulties of the conventional technique, to reduce weight and thickness and to produce a magnetic recording medium excellent in mechanical strength and having a smooth dense surface practically free from pores at a low cost. CONSTITUTION:Polycarbodiimide resin or a polycarbodiimide resin-based compsn. is molded into a proper shape and the resultant molded body is carbonized and worked into the objective substrate for a magnetic recording medium. This substrate is made of glassy carbon produced using the polycarbodiimide resin as starting material.