Patent ID: 6992227

Claim:
A process for production of 1,1,-bis(4-hydroxyphenyl)3,3,5-trimethylcyclohexane which comprises reacting phenol with 3,3,5-trimethylcyclohexanone in the presence of an acid catalyst, separating the resulting phenol adduct crystals of 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane from the resulting reaction mixture, and removing the phenol from the phenol adduct crystals, wherein the phenol adduct crystals are dissolved in a crystallization solvent comprising an aromatic hydrocarbon solvent and water, crystallizing the crystals of 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane out of the crystallization solvent, and collecting the crystals by filtration at temperature of 40–60° C.