METHOD OF MANUFACTURING POLYCARBONATES

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The manufacture of polycarbonates can be accomplished via an ester interchange reaction of a dihydroxy compound and a carbonic acid diester. The method, which can be a single or multi-stage process wherein the total amount of alkali metal compounds and alkaline earth metal compounds contained as impurities is 1x10-7 moles or less per mole of dihydroxy compound used as raw materials, and the catalyst employed is an ammonium and/or phosphonium compound, a compound which decomposes or volatilizes at a temperature of 100 to 300° C., and/or an alkali metal phosphorous containing inorganic salt and/or alkaline earth metal phosphorous-containing inorganic salt.