Hair treatment prepartation

Compositions for the treatment of hair, wherein the improvement comprises the presence in the compositions of a combination of

• A) from 0.1 to 10% by weight of a zwitterionic polymer consisting essentially of:
• .alpha.) monomers containing quaternary ammonium groups corresponding to formula (II):
• R.sup.8 --CH.dbd.CR.sup.9 --CO--Z--(C.sub.n H.sub.2n)--N.sup.(+) R.sup.10 R.sup.11 R.sup.12 A.sup.(-) (II),
• in which R.sup.8 and R.sup.9 independently of one another represent hydrogen or a methyl group and R.sup.10, R.sup.11 and R.sup.12 independently of one another represent alkyl groups having 1 to 4 carbon atoms, Z is an NH group or an oxygen atom, n is an integer of 2 to 5 and A.sup.(-) is the anion of an organic or inorganic acid
• and
• .beta.) monomeric carboxylic acids corresponding to formula (III):
• R.sup.13 --CH.dbd.CR.sup.14 --COOH (III),
• in which R.sup.13 and R.sup.14 independently of one another represent hydrogen or methyl groups, or alkali metal, alkaline earth metal, aluminum or ammonium salts of these acids, and
• B) from 0.1 to 15% by weight of a compound corresponding to formula (I):
• ##STR2## in which at least one of the substituents R.sup.1 to R.sup.3 is a group --COOR.sup.4, where R.sup.4 is hydrogen, an alkali metal ion, an alkaline earth metal ion or .sup.+ NHR.sup.5 R.sup.6 R.sup.7, where R.sup.5 to R.sup.7 independently of one another represent hydrogen, alkyl groups having 1 to 22 carbon atoms, hydroxyalkyl groups having 1 to 4 carbon atoms, alkenyl groups having 2 to 22 carbon atoms, and the remaining substituents R.sup.1 to R.sup.3 represent hydrogen or alkyl groups having 1 to 4 carbon atoms, based on the weight of said compositions.