| abstract |
The invention concerns the use in a cosmetic composition of at least a poly-aminoacid of general formula (I) in which X is -O-, -S- or -NR3; R1 represents in particular a hydrogen atom or a C1-C40 alkyl radical; R2 represents in particular a hydrogen atom or an optionally substituted alkyl radical; R3 represents a hydrogen atom or an alkyl radical; R4 represents a hydrogen atom or a radical such as NH2, OH, SH, -CHOHCH3, -CONH2; n is a number greater than 1 such that the poly-aminoacid derivative molecular weight ranges between 200 and 200000. The invention also concerns the use of said derivatives for keratinous fibre strengthening and care. |