Process for producing polycarbonate
AssigneeIdemitsu Petrochemical Co., Ltd.
InventorsShigeki Kuze, Ryozo Okumura, Yoshinobu Suwabe
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Abstract
There is disclosed a process for producing a polycarbonate which comprises reacting, by the melt method, (A) a dihydroxy compound with (B) a carbonic diester having a chloride contempt derived from chloroformate group of not more than a prescribed level. According to the above process, a polycarbonate which is excellent in transparency, tone of color, heat resistance and water resistance can be efficiently and economically produced.
Claims13
A process for producing a polycarbonate, which comprises transesterifying (A) a dihydroxy compound and (B) a carbonic acid diester having, as an impurity, a chlorine content derived from chloroformate group of at most 30 ppm, which is obtained by subtracting the chlorine content extracted with water using ion chromatography from the total chlorine content contained in said carbonic acid diester determined by potentiometric titration.
Dependencies are inferred from the claim text.