Abstract: The invention relates to non ionic fluorinated compounds having the formula R.sub.F C hd 2H.sub.4 S(R)H, wherein R designates a C.sub.2 H.sub.4 X unit with X=O or S, or a chain exclusively comprising several such units, and two consecutive units can be identical or different, and R.sub.F is a perfluorinated alkyl group exclusive of compounds having the formula:R.sub.F C.sub.2 H.sub.4 SC.sub.2 H.sub.4 OH, R.sub.F C.sub.2 H.sub.4 S(C.sub.2 H.sub.4 O).sub.2 H and R.sub.F (C.sub.2 H.sub.4 S).sub.2 Hand the mixtures of such compounds, in particular, the mixtures of the above defined products differing from one another by the length of their perfluorinated chain, but having the hydrophilic portion of the molecule identical from one product to the other.To obtain them, a compound having the formula R.sub.F C.sub.2 H.sub.

Abstract: The basic composition comprises, in solution in at least one organic solvent, with or without water, from 10 to 40% of a hard-enable organosilicic compound resulting from a first hydrolysis reaction achieved at a temperature lower than 50.degree. C. in the presence of a carboxylic acid and water on at least one R'Si(OR).sub.4 alkoxysilane with n=1 or 2, in association or without association with at least one Si(OR").sub.4 -alkoxysilane, then, a second hydrolysis at a temperature lower than 40.degree. C. after removal of the formed volatile solvents and addition of a less volatile solvent and at least one R"'Si(OR.sub.1).sub.3 -alkoxysilane, said reaction being followed with the setting of the pH to between 3.5 and 5.5 by an organic base.