. . . . . . . . "oups and R9 and R10, which may be identical or different, are a hydrogen atom or alkyl, alkenyl, cycloalkyl or aralkyl radicals containing at about 20 carbon atoms substituted by hydroxyl, alkoxy, amine or quaternary ammonium groups, or if R5 is a hydrogen atom or a substituted aryl or alkyl radical, R6 can be a --COO--M+ radical, M defined as above, and the two radicals, the methylidene-camphor a" .