Abstract: To provide a coating composition which exhibits excellent followability to a difference in level in its application, and which is capable of forming a coating layer having a low refractive index in a short-wavelength region and exhibiting excellent solubility to an alkaline aqueous solution. A coating composition comprising a solvent and a fluorinated polymer (A) which has a unit represented by —[CX1X2—CY(—Rf—COOM)]— and has a number average molecular weight of from 1,000 to 7,500. X1 and X2 are each independently a hydrogen atom, a fluorine atom or a chlorine atom; Y is a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group or a trifluoromethyl group; Rf is a branched perfluoroalkylene group which may contain an etheric oxygen atom between carbon-carbon atoms, or a branched oxyperfluoroalkylene group which may contain an etheric oxygen atom between carbon-carbon atoms; and M is a hydrogen atom or an ammonium ion which may be substituted.

Abstract: To provide a plastic optical fiber using amorphous fluorinated polymers whereby transmission loss and bending loss are low, no cracking takes place during stretching, and a wide range of molding conditions is acceptable.

Abstract: To provide a plastic optical fiber using amorphous fluorinated polymers whereby transmission loss and bending loss are low, no cracking takes place during stretching, and a wide range of molding conditions is acceptable.

Abstract: The present invention provides a method for preparing a compound of CF3CF2CF2OCF?CF2 by pyrolyzing a compound expressed by CF3CF2CF2OCF(CF3)COOCF2CF(CF3)OCF2CF2CF3 in a gas phase at a temperature of from 200° C. to 500° C.

Abstract: A process for producing a fluorinated ester through a small number of steps, is presented. The process for producing a fluorinated ester, comprises a transesterification step in which RAF—COOCF2—RAF and RA—CH2OH are subjected to a transesterification reaction to obtain RAF—COOCH2—RA, and a fluorination step in which the obtained compound is fluorinated to obtain a reaction product containing RAF—COOCF2—RAF. Here, in the formulae, RA is a monovalent organic group, and RAF is the same group as RA or a monovalent organic group obtained by fluorination of RA.

Abstract: A process for producing a fluorinated ester through a small number of steps, is presented. The process for producing a fluorinated ester, comprises a transesterification step in which RAF—COOCF2—RAF and RA—CH2OH are subjected to a transesterification reaction to obtain RAF—COOCH2—RA, and a fluorination step in which the obtained compound is fluorinated to obtain a reaction product containing RAF—COOCF2—RAF. Here, in the formulae, RA is a monovalent organic group, and RAF is the same group as RA or a monovalent organic group obtained by fluorination of RA.

Abstract: A novel polymer useful as an optical resin material excellent in heat resistance, a novel monomer for obtaining the polymer, etc., are provided. A fluorinated diene represented by CF2═CF(CF2)nC(CF3)ROCF═CF2 (wherein R is a fluorine atom or a trifluoromethyl group, and n is an integer of from 1 to 3), and a polymer thereof.

Abstract: A fluorine-containing diene represented by the formula 1: CF2═CF(CF2)nCXYOCF═CF2  Formula 1 wherein each of X and Y which are independent of each other, is an atom selected from a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, provided that X and Y are not simultaneously hydrogen atoms or fluorine atoms, and n is an integer of from 1 to 3.

Abstract: The present invention produces an unsaturated compound (Formula 2) useful as a fluororesin starting material and the like by using a compound of the Formula 1 as a starting material.

Abstract: A novel polymer useful as an optical resin material excellent in heat resistance, a novel monomer for obtaining the polymer, etc., are provided. A fluorinated diene represented by CF2═CF(CF2)nC(CF3)ROCF═CF2 (wherein R is a fluorine atom or a trifluoromethyl group, and n is an integer of from 1 to 3), and a polymer thereof.

Abstract: A fluorine-containing diene represented by the formula 1:

Abstract: A polymer which contains monomer units formed by polymerization of a fluorine-containing diene of formula 1: CF2═CF(CF2)nCXYOCF═CF2 Wherein X and Y are hydrogen and chlorine, hydrogen and-bromine, hydrogen and iodine, fluorine and chlorine, fluorine and bromine, fluorine and iodine, chlorine and bromine, chlorine and iodine, bromine and bromine, bromine and iodine, or iodine and iodine and n is an integer from 1 to 3.

Abstract: A fluorine-containing diene represented by the formula 1: