Cosmetic and dermatological compositions in particular for the treatment of keratin containing substrates

The present invention relates to cosmetic and/or dermatological compositions for the treatment of keratin containing substrates, comprising synergistic mixtures of modified starch polymers with defined molecular weights and cationic charges in a cosmetically acceptable medium. The synergistic mixtures of modified starches employed to manufacture compositions according to the present invention exhibit significant benefits over the existing modified starches employed according to the state-of-the-art in the treatment of keratin-containing substrates like human or animal hair, skin and nails. Another aspect of the present invention is the stabilization of the modified starch solutions used to manufacture the cosmetic and/or dermatological compositions according to the present invention against the growth of micro-organisms without traditional preservatives.