Abstract: A method for preparing .alpha., .beta.-unsaturated carboxylic acids of the formulaR.sub.1 (R.sub.2)C.dbd.C(R.sub.3)CO.sub.2 Hwhere R.sub.1 to R.sub.3 can be hydrogen, fluorine, alkyl, or alkyl containing fluorine, but at least one of R.sub.1 to R.sub.3 is fluorine or alkyl containing fluorine. The method involves reacting an alkenyl halide containing fluorine having the general formulaR.sub.1 (R.sub.2)C.dbd.C(R.sub.3)Xwhere R.sub.1 to R.sub.3 are the same as above, and X is chlorine, bromine, or iodine with carbon dioxide in an aprotic polar organic solvent and in the presence of activated zinc. The activated zinc is activated by pretreatment with a mineral acid or acetic acid. At least one cation is present during the reaction which is an alkali metal ion, alkaline earth metal ion or ammonium ion. The cation is present in an amount of 0.01 to 50 gram atoms per one mol of alkenyl halide containig fluorine. The resulting product is hydrolyzed.

Abstract: Process for producing fluorine-containing aliphatic carboxylic acids having the general formula of Y--R.sub.f --Y' as defined herein by reaction of fluorine-containing aliphatic halogen compounds having the general formula of X--R.sub.4 --X' as defined herein with carbon dioxide under the presence of zinc in an organic solvent and hydrolysis of the reaction product, wherein the improvement comprises controlling the concentration of carbon dioxide in the organic solvent at a level of 0.3 to 5 mol/l.

Abstract: Halogen-containing polyacrylate derivatives having the formula: ##STR1## wherein A is a structural unit derived from a copolymeriazable monomer having a double bond; R is ##STR2## wherein each of R.sub.1 and R.sub.2 is a hydrogen atom or a fluorinated methyl group, provided R.sub.1 and R.sub.2 are not hydrogen atoms at the same time, and R.sub.3 is a hydrogen atom or a lower alkyl group; X is a halogen atom or a methyl group; and m is a positive integer, n is 0 or a positive integer, and n/m from 0 to 2, preferably from 0 to 1 are disclosed.Also disclosed are methods for forming a resist pattern by using the halogen-containing polyacrylate derivatives as a resist material.

Abstract: A halogen-containing polyacrylate derivative having the formula: ##STR1## wherein A is a structural unit derived from a copolymerizable monomer having a double bond; R is ##STR2## wherein each of R.sub.1 and R.sub.2 is a hydrogen atom or a fluorinated methyl group, provided R.sub.1 and R.sub.2 are not hydrogen atoms at the same time, and R.sub.3 is a hydrogen atom or a lower alkyl group; X is a halogen atom or a methyl group; and m is a positive integer, n is 0 or a positive integer, and n/m is from 0 to 2, preferably from 0 to 1.

Abstract: A method of producing a cation-exchange membrane having roughed surface which is characterized in mixing silica powder with water to give a suspended or pasty mixture, supporting the resultant mixture on art paper or filter paper, drying the mixture to form silica powder layer, adhering with heating and pressing the silica powder layer on surface of membrane composed of perfluorocarbon polymer, and removing the silica powder layer formed on the surface of said membrane with caustic alkali aqueous solution.