Abstract: The hair treatment compositions are in a variety of forms including permanent shaping compositions, oxidative after-treatment compositions, hair fixing compositions, hair bleaching compositions, hair cleansing compositions, hair care compositions or hair dye compositions containing direct-dyeing dye compounds and/or a combination of at least one developer and coupler and are characterized by 0.1 to 35 percent by weight of at least one dendrimer, preferably a poly(iminopropane-1,3-diyl)-dendrimer with nitrile and/or amino end groups. Methods of hair treatment based on these hair treatment compositions are described.

Abstract: The aqueous or aqueous/alcoholic cosmetic composition for treating, forming or maintaining a hair style includes from 0.01 to 25 percent by weight of a natural or synthetic hair fixing or thickening polymer and from 0.01 to 2.5 percent by weight of polyamide or silk fibers, each of the polyamide or silk fibers having a length of from 150 to 2000 .mu.m or from 1 to 1100 .mu.m respectively and a diameter of from 8 to 70 .mu.m, so that the polyamide or silk fibers are deposited in the hair when the composition is applied to the hair. In the method of treating, forming or maintaining the hair style the composition is distributed on the hair so that the fibers are deposited in the hair and then the hair is combed, set in the hair style and dried. Other fibers including viscose, polyester, cellulose, flax linen, wool and cotton can be used instead of silk or polyamide in the composition.

Abstract: Cosmetic compositions are disclosed, for the treatment of skin or hair, with a content of new N-hydroxypropyl-chitosan derivatives, composed of (a) 4 to 40 Mol-% units of Formula (I) ##STR1## and (b) 60 to 96 Mol-% units of Formula (II) ##STR2## wherein R.sup.1 and R.sup.2 are the same or different and are each hydrogen or the group ##STR3## with n being equal to an integer from 1 to 5, with the proviso that in at least 50% of the units (II), R.sup.1 and R.sup.2 are not simultaneously hydrogen, or the salts thereof; along with new N-hydroxypropyl-chitosan derivatives and their salts as well a a process for the production of these new compounds from propylene oxide and chitosan.

Abstract: Cosmetic compositions are disclosed, for the treatment of skin or hair, with a content of new N-hydroxypropyl-chitosan derivatives, composed of (a) 4 to 40 Mol-% units of Formula (I) ##STR1## and (b) 60 to 96 Mol-% units of Formula (II) ##STR2## wherein R.sup.1 and R.sup.2 are the same or different and are each hydrogen or the group ##STR3## with n being equal to an integer from 1 to 5, with the proviso that in at least 50% of the units of (II), R.sup.1 and R.sup.2 are not simultaneously hydrogen, or the salts thereof; along with new N-hydroxypropyl-chitosan derivatives and their salts as well as a process for the production of these new compounds from propylene oxide and chitosan.