Process for producing polycarbonates
AssigneeMitsubishi Gas Chemical Company, Inc.
InventorsShu Yoshida, Hiroaki Tanaka
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Abstract
100 parts by weight of the polycarbonate produce by melt polycondensation of a carbonic acid diester and a dihydroxy compound and 0.0001 to 0.1 part by weight of a phosphite compound represented by following Formula (I) are formulated: 1 wherein Rs are each one of a hydrogen atom, an alkyl group, an aryl group, and an oxyalkyl group, where the two Rs are not concurrently hydrogen atoms. The process of the invention can yield polycarbonate molding materials that have satisfactory hue and can be used in a wide variety of applications such for optical materials.
Claims10
A process for producing a polycarbonate, comprising the steps of melt polycondensing a carbonic acid diester and a dihydroxy compound in the presence of a catalytic alkali metal and/or alkaline earth metal to thereby yield a polycarbonate, and incorporating 0.0001 to 0.1 part by weight of a phosphite compound represented by following Formula (I) into 100 parts by weight of the polycarbonate:
- 8
- wherein Rs are each one of a hydrogen atom, an alkyl group containing 1 to 18 carbon atoms, an aryl group, or an oxyalkyl group containing 1 to 8 carbon atoms, where the two Rs are not concurrently hydrogen atoms.
Dependencies are inferred from the claim text.