| 摘要 |
<p>PURPOSE:To recover a usable high-quality polycarbonate resin in a high yield by treating, under specified conditions, waste of optical discs comprising polycarbonate resin substrates and metallic reflecting films formed thereon. CONSTITUTION:A flaky polycarbonate resin is recovered by crushing waste of optical discs, which comprise polycarbonate resin substrates and metallic reflecting films formed thereon, in an aq. base soln. of a concn. of 9wt.% or lower, pref. an aq. NaOH or KOH soln. of a concn. of 1-9wt.%, or in contact with water to an average particle size of 1-10mm, bringing the resulting particles into contact with an aq. base soln. of a concn. of 9wt.% or lower at lower than 75 deg.C, pref. at 40-70 deg.C, to dissolve or separate the metallic films, bringing the remaining particles into contact with an aq. acid soln. (e.g. a dil. aq. hydrochloric acid soln.), washing the particles with water, and drying them.</p> |
