PURPOSE: To produce bisphenol A having high purity and excellent hue and useful as a raw material for epoxy resin and polycarbonate resin in a short time by subjecting a crystal of an addition product of bisphenol A and phenol to dephenolation in solid state at a specific temperature.
CONSTITUTION: The objective bisphenol A is produced by dephenolating (A) a crystal of an adduct of bisphenol A and phenol [e.g. a crystal of an adduct of bisphenol A and phenol having a bisphenol A weight ratio (WA) of 0.5-0.71] at 50-153°C while keeping the solid state. The dephenolation reaction is carried out preferably by dephenolating at 50-98°C under the pressure of inert gas flow until the WA reaches 0.94 and dephenolating at 145-l53°C when WA reaches 0.99 or over. The component A is produced usually by reacting excess phenol with acetone in the presence of an acidic catalyst and crystallizing the reaction product containing bisphenol A.
OOTAKE YUMIKO
ICHIHARA YOSHIJI
SAKATANI TAKASHI
