Abstract: An improved process for the preparation of perfluoropropene oxide by the reaction of perfluoropropene with hydrogen peroxide in an aqueous alkaline medium is described. The improved process is characterized by carrying out the reaction in the presence of a phase-transfer catalyst selected from the group consisting of quaternary ammonium salts, phosphonium salts, and lipophilic complexing agents for cations, and by carrying out the addition of an aqueous solution of an inorganic base to the reaction mixture gradually so that a constant reaction temperature between -10.degree. C. and -60.degree. C. is maintained.

Abstract: A process for the preparation of fluoroalkyl ethers of the formula: ##STR1## wherein: Y is Br or F;X is F, Cl or Br or their mixtures when n is equal to or higher than 2;n is within the range of from 0 to 4;R.sub.f represents a perfluoroalkylene radical containing from 1 to 8 carbon atoms.The process is characterized in that a fluoroalkoxy perfluoroacyl fluoride of the formula: ##STR2## is slowly heated with a salifying agent and a solvent, in the presence of a catalytic amount of N,N-dimethylformamide, with an end temperature within the range of from 60.degree. to 150.degree. C. being reached.

Abstract: Process for the preparation of 2-perfluoropropoxy-perfluoropropionyl fluoride by dimerization of hexafluoropropene epoxide in aprotic polar medium, in the presence of N,N,N',N'-tetrasubstituted diaminodifluoromethane as catalyst, characterized in that the dimerization reaction is carried out in the presence of a co-catalyst constituted by a nitrogenous organic base having structure of aniline, or of pyridine, or of a derivative thereof, wherein the nitrogen atom is not linked to hydrogen atoms and, in the case of the pyridine-type structure, it is sterically hindered by substituent groups on ortho-position relatively to it.

Abstract: Silane quinacridone dyes, composite pigments obtainable therefrom by association with an inorganic substrate, and the processes for preparing them. The dyes have the general formula: ##STR1## wherein X is an --SO.sub.2 NHR group, where R is an alkyl group, linear or branched, having from 1 to 6 carbon atoms, a cycloalkyl group, a phenyl group optionally substituted by one or more alkyl or alkoxy groups (C.sub.1 -C.sub.6), a halogen;Y and Z indicate a silane group having the formula: ##STR2## wherein R.sub.1 is an alkoxy group (C.sub.1 -C.sub.2), R.sub.2 is an alkyl group (C.sub.1 -C.sub.4) or a phenyl group; n is 3, 4 or 5; q is 0 or 1; p and m are integers, such that when q is 1, p is 2 and m is 0, 1 or 2, and when q is 0, p is 3 and m is 0, 1, 2 or 3; W indicates an --SO.sub.3 H group; a, b and c are 0 or 1, selected in such a way that the sum a+b+c is equal to 1.

Abstract: Silane quinacridone dyes, composite pigments obtainable therefrom by association with an inorganic substrate, and the processes for preparing them. The dyes have the general formula: ##STR1## wherein X is an --SO.sub.2 NHR group, where R is an alkyl group, linear or branched, having from 1 to 6 carbon atoms, a cycloalkyl group, a phenyl group optionally substituted by one or more alkyl or alkoxy groups (C.sub.1 -C.sub.6), a halogen; Y and Z indicate a silane group having the formula: ##STR2## wherein R.sub.1 is an alkoxy group (C.sub.1 -C.sub.2), R.sub.2 is an alkyl group (C.sub.1 -C.sub.4) or a phenyl group; n is 3, 4 or 5; q is 0 or 1; p and m are integers, such that when q is 1, p is 2 and m is 0, 1 or 2, and when q is 0, p is 3 and m is 0, 1, 2 or 3; W indicates an --SO.sub.3 H group; a, b and c are 0 or 1, selected in such a way that the sum a+b+c is equal to 1.