Abstract: Disclosed is a fluorine-containing aromatic compound represented by the following general formula (1) and its production method. In the formula (1), R1 is a hydroxyl group or amino group, each of R2 to R5 is independently a hydrogen atom, or a C1-4 straight chain or a C3 or C4 branched chain alkyl group, hydrogen atoms of the alkyl group may partially or totally be replaced with fluorine atoms, n is an integer of 0 to 2, and each of m and l is independently 0 or 1. A polymer derived from this fluorine-containing aromatic compound contains —C(CF3)2OH group at a position away from the polymer main chain. Therefore, it is useful for resist use.

Abstract: An industrially useful process for the production of an aromatic hydroxy compound which comprises reacting an aromatic sulfonic acid alkali metal salt and/or an aromatic sulfonic acid with an alkali metal hydroxide in the presence of a surface active agent, wherein the reaction is effected by uniformly dispersing these-materials in a reaction medium selected from aliphatic, alicyclic and aromatic hydrocarbons. By employing this process, the product can be obtained with high purity, high yield and high selectivity using a minimum amount of the alkali metal hydroxide.

Abstract: 4,4'-dihydroxybiphenyl is prepared by treating biphenyl-4,4'-disulfonic acid or one of its alkali metal salts in an alkali metal hydroxide melt by a process in which the treatment is carried out in a melt which contains from 7 to 14 moles of potassium hydroxide and from 0 to 8 moles of sodium hydroxide, based in each case on 1 mole of biphenyl-4,4'-disulfonic acid, in the presence of an alkali metal carbonate at from 280.degree. to 360.degree. C.

Abstract: An improved process for preparing m-alkylhydroxybenzene which comprises heating alkylbenzene or an isomeric mixture of alkylbenzenesulfonic acid in the presence of sulfuric acid and an inorganic salt at a temperature of from 150.degree. to 210.degree. C. to form an isomeric mixture of alkylbenzenesulfonic acid which is rich in the m-isomer, selectively hydrolyzing the isomers of alkylbenzenesulfonic acid other than the m-isomer, and caustically fusing the unhydrolyzed alkylbenzenesulfonic acid.

Abstract: A process for producing 4,4'-dihydroxydiphenyl which comprises subjecting to alkali fusion 1 mol of 4,4'-diphenyldisulfonic acid and/or potassium 4,4'-diphenyldisulfonate together with 4 to 10 mol of potassium hydroxide and 0.1 to 2 mol of potassium sulfate. Alternatively, the process may comprise subjecting to alkali fusion 4,4'-diphenyldisulfonic acid in the presence of potassium hydroxide, controlling to 20 to 25% the potassium hydroxide concentration in the reaction mixture, and separating dipotassium salt of 4,4'-dihydroxydiphenyl.

Abstract: A process for the preparation of 4,4' dihydroxydiphenyl by acidifying an alkali metal salt of 4,4' dihydroxydiphenyl. The alkali metal salt of 4,4' dihydroxydiphenyl is prepared by fusion of an alkali metal hydroxide with alkali metal diphenyl 4,4' disulfonic acid. Because the reaction may be carried out in granular form, or in a reaction which is made highly fluid by using potassium hydroxide with potassium diphenyl 4,4' disulfonic acid, or by reacting the alkali metal 4,4' disulfonic acid in increments with the hydroxide, low molar ratios of hydroxide to alkali metal diphenyl 4'4, disulfonic acid may be used. When potassium diphenyl 4,4' disulfonic acid is used in accordance with the invention, it is prepared by reacting 4,4' diphenyl disulfonic acid with an inorganic neutral potassium salt.

Abstract: The waste water being formed upon the preparation of hydroxy aromatics, preferably of resorcinol and .beta.-naphthol, by caustic alkaline melt of the corresponding aryl-sulfonic acids or aryl sulfonates is purified by wet oxidation with oxygen or oxygen-containing gases at temperatures of from about 100.degree. to 370.degree. C. and under a pressure of from about 1 to 300 bars. The COD-decomposition rates amount to about 90% and more.When a hydroxy aromatic is prepared by means of a caustic soda melt, this process provides a sulfate, especially sodium sulfate, which is of sufficient purity for further use without complementary purification stages. The obtention of the pure salt is important for the economy of the process.