Method for treating hair, kit, and use of the kit

1. A method for treating hair comprising:

(a) mixing a first composition having a pH from 7 to 13 with a hair treatment composition to form a mixed composition, the hair treatment composition comprising one of a bleaching agent, a coloring agent, and a permanent hair waving agent;

(b1) applying to the hair the mixed composition having a pH from 7 to 13; and

(c) applying to the hair a second composition having a pH from 3 to 7, wherein

each of the first composition and the second composition comprises in a cosmetically acceptable carrier, one or more at least bi-functional carboxylic acids of Formula 1, or cosmetically acceptable salts thereof, or mixtures thereof,

wherein Formula 1 is HOOC—Ra-(O—Rb)n-COOH, wherein Ra is selected from the group consisting of C1-C10 alkylene, C1-C10 cycloalkylene, C1-C10 alkenylene, C6-C12 (alkyl)arylene, Rb is C2-C4 alkylene, n is an integer from 0 to 4, wherein Ra or each Rb are substituted with one or more substituents selected from —COOH, —OH, —NH2, —SH, and ═O, and wherein the total number of carbon atoms in Ra plus Rb is 12 or less.

2. The method of claim 1 , wherein a difference between the pH of the first composition and the pH of the hair treatment composition is 1.5 or less.

3. The method of claim 1 , wherein a difference between the pH of the hair treatment composition and the pH of the mixed composition is 0.3 or less.

4. The method of claim 1 , wherein the hair treatment composition comprises one or more oxidizing agents, oxidative dye precursors including one or more couplers and one or more primary intermediates, or both oxidizing agent(s) and oxidative dye precursors.

5. The method of claim 1 , wherein the hair treatment composition comprises one or more reducing agents.

6. The method of claim 1 , wherein the one or more at least bi-functional carboxylic acid of the first composition and of the second composition are identical.

7. The method of claim 1 , wherein the one or more at least bi-functional carboxylic acid is selected from the group consisting of Oxalic Acid, Malonic Acid, Succinic Acid, Glutaric Acid, Adipic Acid, Pimelic Acid, Suberic Acid, Azelaic Acid, Sebacic Acid, Maleic Acid, Fumaric Acid, Glutaconic Acid, Traumatic Acid, Muconic Acid, Glutinic Acid, Citraconic Acid, Mesaconic Acid, Malic Acid, Aspartic Acid, Glutamic Acid, Tartronic Acid, Tartaric Acid, Diaminopimelic Acid, Saccharic Acid, Mesoxalic Acid, Oxaloacetic Acid, Acetonedicarboxylic Acid, Arabinaric Acid, Phthalic Acid, Isophthalic Acid, Terephthalic Acid, Diphenic Acid, 2,6-Naphthalenedicarboxylic Acid, Citric Acid, Isocitric Acid, Aconitic Acid, Propane-1,2,3-tricarboxylic Acid, Trimesic Acid, Methanetetracarboxylic Acid, 1,2,3,4-Benzenetetracarboxylic Acid, 2,2′-(ethane-1,2-diylbis(azanediyl))disuccinic Acid, Aspergillomarasine Acid, Ethylenetetracarboxylic Acid, or derivatives thereof, or cosmetically acceptable salts thereof.

8. The method of claim 1 , wherein the first composition comprises from 0.1% to 25% of the one or more at least bi-functional carboxylic acid, or cosmetically acceptable salt thereof, by total weight of the first composition, or wherein the second composition comprises from 0.1% to 25% of the one or more at least bi-functional carboxylic acid, or cosmetically acceptable salt thereof, by total weight of the second composition.

9. The method of claim 1 , wherein the first composition has a pH from 7.5 to 12 and wherein the second composition has a pH from 3.5 to 6.5.

10. The method of claim 1 , wherein the first composition is substantially free of a further component selected from the group of diamines, polyamines, primary amines, fatty acids, silicones, oxidative dye precursors, direct dyes, reducing agents, unsaturated compounds having one or more carboxylic acid groups, and mixtures thereof.

11. The method of claim 1 , further comprising:

(d) rinsing, shampooing, conditioning the hair, or a combination thereof, wherein step (d) occurs subsequent to step (bi) or step (c).

12. A kit comprising:

(1) a first composition having a pH from 7 to 13;

(2) a second composition having a pH from 3 to 7;

wherein each of the first and the second composition comprises in a cosmetically acceptable carrier, one or more at least bi-functional carboxylic acids of Formula 1, or cosmetically acceptable salts thereof, or mixtures thereof;

wherein Formula 1 is HOOC—Ra-(O—Rb)n-COOH, wherein Ra is selected from the group consisting of C1-C10 alkylene, C1-C10 cycloalkylene, C1-C10 alkenylene, C6-C12 (alkyl)arylene, Rb is C2-C4 alkylene, n is an integer from 0 to 4, wherein Ra or each Rb are substituted with one or more substituents selected from —COOH, —OH, —NH2, —SH, and ═O, and wherein the total number of carbon atoms in Ra plus Rb is 12 or less;

wherein the first composition, and the second composition are, separately packaged.