TREATMENT OF PHOTOMAGNETIC RECORDING DISK WASTE

摘要

PURPOSE: To recover a polycarbonate resin of good quality in high yield from waste of a photomagnetic recording disk (MOD) having a polycarbonate resin substrate. CONSTITUTION: Waste of a photomagnetic recording disk (MOD) having a polycarbonate resin substrate is subjected to wet grinding while brought into contact with a base aq. soln. or water to obtain flakes with an average particle size of 0.5-10mm. These flakes are brought into contact with a base aq. soln. with a concn. of 9wt.% or less to be treated within a temp. range of 30 - below 75 deg.C and the treated flakes are neutralized by an acid aq. soln. to be washed and dried to efficiently recover a polycarbonate resin of high quality.