Hair treatment compositions incorporating hair substantive polymers

A hair treatment conditioner composition comprising:

• a) 0.05-5% by wt. of a cationic conditioning surfactant corresponding to general formula:
• [N(R1)(R2)(R3)(R4)]+(X)−
• in which R1, R2, R3, and R4 are independently selected from (a) an aliphatic group of from 1 to 22 carbon atoms, or (b) an aromatic, alkoxy, polyoxyalkylene, alkylamido, hydroxyalkyl, aryl or alkylaryl group having up to 22 carbon atoms;
• and X is a salt-forming anion selected from halogen, acetate, citrate, lactate, glycolate, phosphate, nitrate, sulphate, and alkylsulphate radicals;
• b) 0.1 to 10% by wt. of fatty material which is fatty alcohol, alkoxylated fatty alcohol, fatty acid or mixtures thereof,
• the ratio of cationic surfactant to fatty alcohol being 10:1 to 1:10;
• and
• c) 0.1 to 5% by wt. of a hair substantive polymer, the hair substantive polymer comprising a polymeric backbone bearing:
• (i) at least one side chain which is formed from a hair fibre targeting group which is covalently linked to the polymeric backbone, said hair fibre targeting group being a non-cationic species which is capable of specifically interacting with the protein surface of the hair fibre in a non-covalent interaction having a bond energy ranging from 0.5 to 3 Kcal/mol, when the composition is applied to hair;
• wherein said targeting group comprises a partial ester of poly(hydroxyethylacrylate) with 3,4-dihydroxybenzoic acid, a partial ester of poly(hydroxyethylmethacrylate) with 3,4-dihydroxybenzoic acid or mixtures thereof;
• (ii) optionally, at least one side chain different from side chain (i) and which different side chain comprises a hair benefit agent.