HAIR TREATMENT METHOD

Abstract

A method of repairing damaged hair, comprising the step of applying a composition to the hair, wherein the composition comprises a soluble zinc compound and a cleansing surfactant; and wherein the composition has a pH of from 3 to 5.

Claims

1. A method of repairing damaged hair, comprising the step of applying a composition to the hair, wherein the composition comprises a soluble zinc compound selected from zinc sulphate, zinc chloride, zinc gluconate, zinc acetate, zinc citrate and mixtures thereof and a cleansing surfactant selected from anionic surfactant, non-ionic surfactant, amphoteric surfactant and zwitterionic surfactant and mixtures thereof; and wherein the composition has a pH of from 3 to 5.

2. A method according to claim 1 in which the zinc compound is zinc sulphate.

3. A method according to any preceding claim in which level of zinc compound in the total composition is preferably from 0.005 to 10 wt %, more preferably from 0.01 to 5 wt %, most preferably from 0.05 to 2 wt % by weight of the total composition.

4. A method according to any preceding claim wherein the cleansing surfactant is anionic surfactant.

5. A method according to any preceding claim which comprises the step of rinsing the composition from the hair.

6. A method according to any preceding claim which provides damage repair to hair, preferably to hair protein, preferably an increase in the denaturation temperature of the internal protein of hair.

7. A method as claimed in claim 6, wherein the cause of the damage is selected from mechanical means, chemical means and environmental means.

8. Method as claimed in claim 7, wherein the damage is selected from lightening, chemical straightening, colouring, heat styling, and mixtures thereof.

9. A method according to any preceding claim comprising the following sequential steps i) application of a composition comprising a zinc compound, a cleansing surfactant and having a pH of 3-6, for a maximum time period of 20 minutes; and ii) rinsing the hair.

10. Use of a composition comprising a soluble zinc compound, to repair damage to internal hair protein.

11. Use as claimed in claim 10 wherein the composition is a composition as defined in any of claims 1-9.

Description

EXAMPLES

[0077] The Hair

[0078] Virgin: The hair used in the following examples was dark brown European hair tresses 2 grams and 10 inches long.

[0079] Bleached: Virgin hair tresses were bleached according to the following protocol. Hair was bleached for 30 minutes with commercial bleaching powder mixed with 9% cream peroxide, 30 ‘vol’. Hair was then washed with 14% aqueous sodium laureth ether sulphate (SLES) solution before drying.

[0080] The double-bleached hair was dialysed prior to the experiments in 5 L of distilled water over a period of 72 hours, and the water was changed 3 times over this period. After dialysing, the hair tresses were left to dry overnight in a controlled environment (20° C. and 50% relative humidity).

[0081] The Compositions

[0082] Composition 1, in accordance with the invention, is a shampoo composition.

[0083] Compositions A is a Comparative shampoo that does not contain any damage repair agents.

[0084] The compositions 1 and A are given in Table 1 below.

TABLE-US-00001 TABLE 1 Ingredients (wt %) of Composition 1 in accordance with the invention and comparative composition A. Amount (wt %) Ingredient 1 A Zinc Sulphate 1.5 — heptahydrate Suspending 0.3 0.3 agent Sodium Laureth 14.0 14.0 Ether Sulfate Co-surfactant 1.6 1.6 Deposition aid 0.2 0.2 Silicone 3 3 Sodium Chloride 0.55 0.55 Perfume 0.55 0.55 Water & minors to 100 to 100 PH 4.8 6.0

[0085] Treatment of the Hair

[0086] Hair (virgin and double-bleached) was first treated twice with an aqueous composition containing 14% Sodium Laureth Ether Sulphate (SLES) at 0.1 ml/1 g hair using 30 seconds lathering and 30 seconds rinse in tap water.

[0087] The hair was then treated with shampoo Composition 1 or A using the following method: 0.1 ml/1 g hair applied and lathered for 30 seconds followed by 30 seconds rinse in tap water. After removing excess water, hair treatment was repeated. The hair tresses were then left to dry overnight at 20° C., 50% relative humidity.

[0088] Effect of Treatment by Composition 1 and Comparative Composition a on Hair Protein

[0089] In order to prepare hair samples for Differential Scanning calorimetry (DSC), 1 inch of hair was cut from the tip-end of each tress. Hair was then chopped into 1-2 mm sections.

[0090] Measurements were performed using a Mettler-Toledo DSC (with auto-sampler). 7-10 mg samples of dry, finely chopped hair was placed in the ‘Medium Pressure Stainless Steel DSC Pans’ and accurately weighed. 50 microlitres of deionised water was then added to each sample after which the pan lid was put on and the pans crimped shut to provide a hermetic seal. Pans were equilibrated for a minimum of 24 h ahead of any measurement to allow the hair to fully hydrate. The DSC was programmed to first heat each sample to 100° C. for 3 min and then to warm them further from 100 to 180° C. at a constant rate of 5° C. min′.

TABLE-US-00002 TABLE 2 Mean denaturation temperatures and change in denaturation temperature for treatment with Composition 1 in accordance with the invention and Comparative Composition A. Mean Denaturation Standard Deviation Treatment Temperature (° C.) (+/−) Virgin Hair 147.17 0.33 Double bleached hair 142.58 0.11 Double bleached hair + 148.88 0.61 Composition 1 Double bleached hair + 142.58 0.11 Composition A

[0091] It will be seen that hair treated with Shampoo Composition A has low denaturation temperature due to the nature of bleached hair. Shampoo Composition 1, in accordance with the invention, increases the denaturation temperature of bleached hair to higher that of virgin hair.