Cationic or cationizable polyurethane with elastic character

A cosmetic composition comprising, in a cosmetically acceptable medium, a cationic or cationizable polyurethane with elastic character formed by the reaction of:

• (a1) at least one cationic or cationizable unit resulting from at least one tertiary or quaternary amine having at least two reactive functions with labile H,
• (a2) at least one mixture of at least two different non-ionic units having at least two reactive functions with labile H,
• (b) at least one compound comprising at least two isocyanate functions, wherein the at least one mixture of non-ionic units (a2) comprises a mixture of
• at least one first non-ionic polymer chosen from olefin homopolymers and copolymers, and
• at least one second non-ionic polymer different from an olefin copolymer and chosen from non-ionic homopolymers and copolymers, and
• further wherein said at least one first non-ionic polymer and said at least one second non-ionic polymer bear at their ends reactive functions with labile hydrogen and having a glass transition temperature (Tg), measured by differential scanning calorimetry, less than 10° C.

A process for forming a protecting film on nails, said process comprising applying to nails a cationic or cationizable polyurethane with elastic character formed by the reaction of:

• (a1) at least one cationic or cationizable unit resulting from at least one tertiary or quaternary amine having at least two reactive functions with labile H,
• (a2) at least one mixture of at least two different non-ionic units having at least two reactive functions with labile H,
• (b) at least one compound comprising at least two isocyanate functions, wherein the at least one mixture of non-ionic units (a2) comprises a mixture of
• at least one first non-ionic polymer chosen from olefin homopolymers and copolymers, and
• at least one second non-ionic polymer different from an olefin copolymer and chosen from non-ionic homopolymers and copolymers, and
• further wherein said at least one first non-ionic polymer and said at least one second non-ionic polymer bear at their ends reactive functions with labile hydrogen and having a glass transition temperature (Tg), measured by differential scanning calorimetry, less than 10° C.

A process for permanent styling of hair, said process comprising applying to said hair a cationic or cationizable polyurethane with elastic character formed by the reaction of:

• (a1) at least one cationic or cationizable unit resulting from at least one tertiary or quaternary amine having at least two reactive functions with labile H,
• (a2) at least one mixture of at least two different non-ionic units having at least two reactive functions with labile H,
• (b) at least one compound comprising at least two isocyanate functions, wherein the at least one mixture of non-ionic units (a2) comprises a mixture of
• at least one first non-ionic polymer chosen from olefin homopolymers and copolymers, and
• at least one second non-ionic polymer different from an olefin copolymer and chosen from non-ionic homopolymers and copolymers, and
• further wherein said at least one first non-ionic polymer and said at least one second non-ionic polymer bear at their ends reactive functions with labile hydrogen and having a glass transition temperature (Tg), measured by differential scanning calorimetry, less than 10° C.

A process for making a cosmetic composition in a form chosen from styling lacquers, mousses and gels, said process comprising including in said cosmetic composition a cationic or cationizable polyurethane with elastic character formed by the reaction of:

• (a1) at least one cationic or cationizable unit resulting from at least one tertiary or quaternary amine having at least two reactive functions with labile H,
• (a2) at least one mixture of at least two different non-ionic units having at least two reactive functions with labile H,
• (b) at least one compound comprising at least two isocyanate functions, wherein the at least one mixture of non-ionic units (a2) comprises a mixture of
• at least one first non-ionic polymer chosen from olefin homopolymers and copolymers, and
• at least one second non-ionic polymer different from an olefin copolymer and chosen from non-ionic homopolymers and copolymers, and
• further wherein said at least one first non-ionic polymer and said at least one second non-ionic polymer bear at their ends reactive functions with labile hydrogen and having a glass transition temperature (Tg), measured by differential scanning calorimetry, less than 10° C.

A process for cosmetically treating hair, said process comprising

• applying to hair a cationic or cationizable polyurethane with elastic character formed by the reaction of:
• (a1) at least one cationic or cationizable unit resulting from at least one tertiary or quaternary amine having at least two reactive functions with labile H,
• (a2) at least one mixture of at least two different non-ionic units having at least two reactive functions with labile H,
• (b) at least one compound comprising at least two isocyanate functions, wherein the at least one mixture of non-ionic units (a2) comprises a mixture of
• at least one first non-ionic polymer chosen from olefin homopolymers and copolymers, and
• at least one second non-ionic polymer different from an olefin copolymer and chosen from non-ionic homopolymers and copolymers, and
• further wherein said at least one first non-ionic polymer and said at least one second non-ionic polymer bear at their ends reactive functions with labile hydrogen and having a glass transition temperature (Tg), measured by differential scanning calorimetry, less than 10° C.