COLORING METHOD FOR POLYCARBONATE RESIN MOLDED PRODUCT FOR OPTICAL MEMBER

摘要

PURPOSE:To obtain the title molded product at low cost without the need for any complicated large-scale equipment by mixing a polycarbonate resin with a liquid colorant prepared by dispersing a colorant such as dye and/or pigment in a dispersant consisting of a specific saturated fatty acid ester and by melting followed by molding. CONSTITUTION:Firstly, a liquid colorant is prepared by dispersing a colorant such as dye and/or pigment in a dispersant consisting of a saturated fatty acid ester, a full-ester of (1) a 4-35C straight chain saturated monofunctional fatty acid or 4-35C branched saturated monofunctional fatty acid and (2) a 2-35C saturated monohydric or polyhydric alcohol. Thence, 0.05-2 pts.wt. of this colorant is added from a container 1 through a pump 3 to 100 pts.wt. of a polycarbonate resin 8 for optical members put in a hopper 7 of an extruder or injection molding machine followed by heating and melting. The resulting melt is then mixed on a screw conveyor 10 and extruded or injected through a nozzle 12, thus obtaining the objective colored molded product.