Abstract: 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 a temperature of 40–60° C.

Abstract: The invention provides a process for production of high purity 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (BPTMC) which comprises: (a) a reaction step wherein phenol is reacted with 3,3,5-trimethylcyclohexanone (TMC) in a slurry containing phenol adduct crystals of BPTMC in the presence of an acid catalyst; (b) a neutralization step wherein after the reaction, the resulting reaction mixture in the form of slurry is neutralized with an alkali while heating to convert the slurry to a solution; (c) a primary crystallization and filtration step wherein the resulting solution is cooled and the resulting phenol adduct crystals of BPTMC are collected by filtration; (d) a secondary crystallization and filtration step wherein the adduct crystals obtained in the primary crystallization and filtration step are heated in a crystallization solvent to dissolve the crystals therein to prepare a solution and then the solution is cooled to crystallize BPTMC out of the solution, followed by collecting the crystals of

Abstract: 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 wherein the reaction of phenol with 3,3,5-trimethylcyclohexanone is started in a slurry comprising phenol adduct crystals of 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and hydrated phenol in the presence of an acid catalyst, and then the reaction is continued in the slurry.

Abstract: 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, adding an aqueous solution of an alkali to the resulting reaction mixture to neutralize it, removing a water phase from the thus neutralized reaction mixture, cooling the resulting oil phase to crystallize phenol adduct crystals of 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane while obtaining a primary crystallization filtrate, wherein the primary crystallization filtrate is heated to a temperature of 150-250° C. in the presence of an alkali catalyst in an inert gas atmosphere under a reduced pressure to thermally decompose 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane in the primary crystallization filtrate.

Abstract: The invention provides a process for production of 1,3-di(2-p-hydroxyphenyl-2-propyl)benzene which comprises: reacting 1,3-di(2-hydroxy-2-propyl)benzene with phenol in an amount of 4-6 times in mols the amount of the 1,3-di(2-hydroxy-2-propyl)benzene in the presence of an acid catalyst at a temperature of 10-55° C. thereby crystallizing adducts formed of phenol and the resulting 1,3-di(2-p-hydroxyphenyl-2-propyl)benzene so that the reaction is effected in a slurry, and then recovering 1,3-di(2-p-hydroxyphenyl-2-propyl)benzene from the adduct.

Abstract: A process for producing a 3,3,5-trimethylcyclohexylidenebisphenol, comprising pre-reacting a phenol (A), i.e., phenol whose 2- and 6-positions may be monosubstituted or disubstituted with an alkyl group having 1 to 4 carbon atoms, with 3,3,5-trimethylcyclohexanone (B) at a molar ratio ((A)/(B)) of 3 to 7 in the presence of an acid catalyst until 3,3,5-trimethylcyclohexanone (B) exhibits a degree of conversion of at least 90 mol %; adding the phenol (A) and/or an aromatic hydrocarbon (C) to the thus obtained reaction mixture; and post-reacting the resultant mixture. This process enables not only suppressing a rise of the viscosity of the reaction mixture but also obtaining the desired product at high yield. Therefore, this process is applicable to not only the productivity enhancement in batch processing but also a continuous reaction processing which has been regarded as being difficult.