WO2009092750A1

WO2009092750A1 - Hair relaxing composition

Info

Publication number: WO2009092750A1
Application number: PCT/EP2009/050691
Authority: WO
Inventors: Cheryl Anne Taylor
Original assignee: Unilever Plc; Unilever N.V.; Hindustan Unilever Limited
Priority date: 2008-01-25
Filing date: 2009-01-22
Publication date: 2009-07-30

Abstract

A hair relaxing kit comprising two compositions: i) the first composition comprising a hair relaxing composition; and ii) the second composition comprising emulsified particles of an amino functional silicone of general formula: Si(CH3)3 - O - [Si(CH3)2 - O - ]x - [Si (CH3) (R - NH - CH2CH2NH2) - O -]y - Si(CH3)3 wherein x + y is a number from about 50 to about 500, and wherein R is an alkylene group having from 2 to 5 carbon atoms; in which the amino functional silicone has a mole % amine functionality of at least 1 mole % and a non-amino functionalised silicone.

Description

HAIR RELAXING COMPOSTITION

The present invention is directed to a hair relaxing kit.

Hair relaxers are compositions used to relax or straighten curly or kinky hair. Most hair relaxers straighten hair by disrupting disulfide bonds of the hair fibres with an alkaline agent or reducing agent. The chemical disruption of disulfide bonds is usually combined with mechanical straightening of the hair (e.g. by combing) . The straightening process is generally terminated by rinsing and/or the application of a neutralizing composition.

A source of hydroxide ions is usually the preferred alkaline agent used to straighten hair. The term "lanthionizing" is used when referring to hair relaxed or straightened by hydroxide ions, as the straightening reaction sequence with hydroxide ions results in lanthionine residue formation.

Most frequently, commercial relaxing compositions are in the form of gels or emulsions and contain varying proportions of strong water- soluble bases, such as sodium hydroxide (NaOH) . Also used are slightly-soluble metal hydroxides, such as calcium hydroxide (Ca(OH)₂), which can be converted in situ to soluble bases, such as guanidine hydroxide .

A key problem with hair relaxers is that they leave the hair treated therewith feeling rough, unconditioned and brittle. The present invention relates to hair relaxing systems which leave the hair less prone to breakage and feeling smooth.

The present invention relates to a hair relaxing kit comprising two compositions: i) the first composition comprising a hair relaxing composition; and ii) the second composition comprising emulsified particles of an amino functional silicone of general formula:

Si(CH₃)₃ - O - [Si (CH₃) 2 - O - ]x - [Si (CH₃) (R - NH - CH₂CH₂ NH₂) - O -]y - Si (CH₃) ₃

wherein x + y is a number from about 50 to about 500, and wherein R is an alkylene group having from 2 to 5 carbon atoms; in which the amino functional silicone has a mole % amine functionality of at least 1 mole % and a nonamino functionalised silicone.

A further aspect of the invention relates to a method for relaxing hair comprising the following steps:

i) applying to the hair for a sufficient period of time to lanthionize the hair a relaxer composition; ii) terminating the lanthionization process; iii) applying to the hair a post-lanthionization composition comprising an amino functional silicone of general formula: S i ( CH₃ ) ₃ - O - [ S i ( CH₃ ) ₂ - O - ] x - [ S i ( CH₃ ) ( R - NH - CH₂CH₂ NH₂ ) - O - ] y - S i ( CH₃ ) ₃

wherein x + y is a number from about 50 to about 500, and wherein R is an alkylene group having from 2 to 5 carbon atoms; in which the amino functional silicone has a mole % amine functionality of at least 1 mole % and a non-amino functionalised silicone.

As disclosed above the present invention relates to post- treatment composition for application after application of a relaxing composition. In the context of the present invention "relaxing composition" means a composition comprising at least one hydroxide ion generator in an amount sufficient to effect lanthionization of keratin fibres. The term post-treatment refers to a treatment applied to the hair after the lathionization process, and preferably after any subsequent termination process.

The hydroxide ion generator may be chosen from those compositions that produce hydroxide ions appropriate for the lanthionization of hair. As used herein, "hydroxide ion generator" refers to both compounds and compositions that generate hydroxide ions, and compounds and compositions that comprise hydroxide ions. Hydroxide ion generators may, for example, be chosen from traditional "lye" and "no lye" hair relaxer compositions and other soluble or slightly soluble hydroxide ion sources. Preferred hydroxide ion generators are strong water- soluble bases, particularly preferred is sodium hydroxide. The post lanthionization composition comprises amino functional silicone.

Post-lanthionization compositions according to the invention include emulsified particles of an amino functionalised silicone of general formula: Si (CH₃) ₃-0-[Si (CH₃) ₂-0-] x- [Si (CH₃) (R-NH CH₂CH₂ NH₂) -0-] y-Si (CH₃) ₃ wherein x + y is a number from about 50 to about 500, and wherein R is an alkylene group having from 2 to 5 carbon atoms. Preferably, the number x + y is in the range of from about to about 300. The amino functional silicone is insoluble in the aqueous matrix of the hair conditioning composition and so is present in an emulsified form, with the silicone present as dispersed particles.

Amino functional silicones suitable for use in the invention need to have a mole percent amino functionality of at least 1.0 mole %. Suitably the mole percent amino functionality of the amino functional silicone ranges from 1 to 8.0 mole %, preferably from 1 to 5.0 mole %, such as 1.7 mole %.

Pre-formed emulsions of amino functionalised silicone are available from suppliers of silicone oils such as Dow Corning, General Electric, Union Carbide, Wacker Chemie, Shin Etsu, Toshiba, Toyo Beauty Co, and Toray Silicone Co. Examples include emulsions DC2-8320, DC2-8306, DC2-8177 and DC2-8467, all available from Dow Corning.

Emulsified, non-amino functionalised silicone Hair conditioning compositions of the invention may suitably also comprise emulsified particles of a non-amino functionalised silicone, which is insoluble in the aqueous matrix of the composition and so is present in an emulsified form, with the silicone present as dispersed particles. Suitable non-amino functionalised silicones include polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone. Also suitable for use in hair conditioning compositions of the invention are polydimethyl siloxanes having hydroxyl end groups, which have the CTFA designation dimethiconol . Also suitable for use in hair conditioning compositions of the invention are silicone gums having a slight degree of cross-linking, as are described for example in WO 96/31188. These materials can impart body, volume and stylability to hair, as well as good wet and dry conditioning.

The viscosity of the emulsified non-amino functionalised silicone itself (not the emulsion or the final hair conditioning composition) is typically at least 10,000 cst. In general we have found that conditioning performance increases with increased viscosity. Accordingly, the viscosity of the silicone itself is preferably at least 60,000 cst, most preferably at least 500,000 cst, ideally at least 1,000,000 cst. Preferably the viscosity does not exceed 109 cst for ease of formulation.

Emulsified non-amino functional silicones for use in hair conditioning compositions of the invention will typically have an average silicone particle size in the composition of less than 30, preferably less than 20, more preferably less than 10 microns. Again, we have found that reducing the particle size generally improves conditioning performance. Most preferably the average silicone particle size of the emulsified non-amino functional silicone in the composition is less than 2 microns, ideally it ranges from 0.01 to 1 micron. Suitable non-amino functional silicone emulsions for use in the invention are also commercially available in a pre-emulsified form. Examples of suitable pre-formed emulsions include emulsions DC2-1766, DC2-1784, and microemulsions DC2-1865 and DC21870, all available from Dow Corning. These are all emulsions/microemulsions of dimethiconol . Cross-linked silicone gums are also available in a pre-emulsified form, which is advantageous for ease of formulation. Preferred examples of these materials available from Dow Corning are DC X21787, (which is an emulsion of cross-linked dimethiconol gum) and DC 2-7121.

A further preferred example is the material available from Dow Corning as DC X2-1391, which is a microemulsion of cross-linked dimethiconol gum.

The total amount of silicone (amino functional and non-amino functional, if present) incorporated into the hair conditioning compositions of the invention depends on the level of conditioning desired and the material used. A preferred amount is from 0.01 to about 10% by weight of the total composition although these limits are not absolute. The lower limit is determined by the minimum level to achieve conditioning and the upper limit by the maximum level to avoid making the hair and/or skin unacceptably greasy. We have found that preferably a total amount of silicone of from 0.3 to 8 wt% -, more preferably 2 to 7wt%, by weight of the total composition is a suitable level. Conditioning surfactants are preferably selected from cationic surfactants, used singly or in admixture. Examples include quaternary ammonium hydroxides or salts thereof, e.g. chlorides. Suitable cationic surfactants for use in hair conditioning compositions of the invention include cetyltrimethylammonium chloride, behenyltrimethylammonium chloride, cetylpyridinium chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride, didodecyldimethylammonium chloride, dioctadecyldimethy1ammonium chloride, tallowtrimethylammonium chloride, cocotrimethylammonium chloride, and the corresponding hydroxides thereof. Further suitable cationic surfactants include those materials having the CTFA designations Quaternium-5, Quaternium-31 and Quaternium-18.

Mixtures of any of the foregoing materials may also be suitable. Particularly useful cationic surfactant for use in hair conditioners of the invention are cetyltrimethylammonium chloride and behenyltrimethylammonium chloride In hair conditioning compositions of the invention, the level of cationic surfactant is preferably from 0.01 to 10%, more preferably 0.05 to 5%, most preferably 0.1 to 2% by weight based on total weight of the composition. Fatty Alcohol

Hair conditioning compositions of the invention advantageously incorporate a fatty alcohol material. The combined use of fatty alcohol materials and cationic surfactants in conditioning compositions is believed to be especially advantageous, because this leads to the formation of a lamellar phase, in which the cationic surfactant is dispersed. Representative fatty alcohols comprise from 8 to 22 carbon atoms, more preferably 16 to 20. Examples of suitable fatty alcohols include cetyl alcohol, stearyl alcohol and mixtures thereof. The use of these materials is also advantageous in that they contribute to the overall conditioning properties of compositions of the invention. Alkoxylated, (e.g. ethoxylated or propoxylated) fatty alcohols having from about 12 to about 18 carbon atoms in the alkyl chain can be used in place of, or in addition to, the fatty alcohols themselves. Suitable examples include ethylene glycol cetyl ether, polyoxyethylene (2) stearyl ether, polyoxyethylene (24) cetyl ether, and mixtures thereof. The level of fatty alcohol and/or alkoxylated fatty alcohol material in conditioners of the invention is conveniently from 0.01 to 10%, preferably from 0.1 to 5% by weight of the composition. The weight ratio of cationic surfactant to fatty alcohol and/or alkoxylated fatty alcohol is suitably from 10:1 to 1:10, preferably from 4:1 to 1:8, optimally from 1:1 to 1:4.

- other optional ingredients Compositions of this invention may contain any other ingredient normally used in hair treatment formulations. These other ingredients may include viscosity modifiers, preservatives, colouring agents, polyols such as glycerine and polypropylene glycol, chelating agents such as EDTA, antioxidants, fragrances, and sunscreens. Each of these ingredients will be present in an amount effective to accomplish its purpose. Generally these optional ingredients are included individually at a level of up to about 5% by weight of the total composition.

Preferably, compositions of this invention also contain adjuvants suitable for hair care. Generally such ingredients are included individually at a level of up to 2%, preferably up to 1%, by weight of the total composition.

Among suitable hair care adjuvants, are: (i) natural hair root nutrients, such as amino acids and sugars. Examples of suitable amino acids include arginine, cysteine, glutamine, glutamic acid, isoleucine, leucine, methionine, serine and valine, and/or precursors and derivatives thereof. The amino acids may be added singly, in mixtures, or in the form of peptides, e.g. di-and tripeptides. The amino acids may also be added in the form of a protein hydrolysate, such as a keratin or collagen hydrolysate. Suitable sugars are glucose, dextrose and fructose. These may be added singly or in the form of, e.g. fruit extracts. A particularly preferred combination of natural hair root nutrients for inclusion in compositions of the invention is isoleucine and glucose. A particularly preferred amino acid nutrient is arginine . - hair fibre benefit agents. Examples are : -ceramides, for moisturising the fibre and maintaining cuticle integrity. Ceramides are available by extraction from natural sources, or as synthetic ceramides and pseudoceramides . A preferred ceramide is Ceramide II, ex Quest. Mixtures of ceramides may also be suitable, such as Ceramides LS, ex Laboratoires Serobiologiques .

- fatty acids, for cuticle repair and damage prevention. Examples are branched chain fatty acids such as 18 methyleicosanoic acid and other homologues of this series, straight chain fatty acids such as stearic, myristic and palmitic acids, and unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid and arachidonic acid. A preferred fatty acid is oleic acid. The fatty acids may be added singly, as mixtures, or in the form of blends derived from extracts of, e.g. lanolin.

Mixtures of any of the above active ingredients may also be used. A particularly preferred combination is arginine and oleic acid.

This post treatment composition may be in any form preferably in the form chosen from emulsions, solutions, suspensions, gels, creams, and pastes.

A preferred method of terminating the lanthionization process is by rinsing the hair with water.

The invention will now be illustrated by the following non- limiting Examples. Examples

Testing methodology

Protocol

12 Mulatto supplied (IPP) switches (6" 2.5gm wide clip) were separated into sets, each set containing 4 switches. Switches were relaxed sequentially for 3 times following the protocol;

Each switch was coated directly with 5gms of relaxer cream as in table 1 containing 2.2% Sodium hydroxide. The cream was applied directly to the switches using a brush. The switch was then flipped over and the application of cream repeated. Total weight of relaxer applied was lOgms.

The switches were left undisturbed at ambient temperature for 30 minutes.

The switches were rinsed with tepid running water for 1 minute, followed by treating with commercially provided neutralising shampoo for 30 seconds. The switches were then again rinsed before towel drying. The treated switches were then allowed to dry in a vertical position for 45 minutes in a drying cabinet with a temperature setting of 50⁰C before re applying the relaxer cream. This was repeated until all 4 switches have had 3 applications of relaxer cream applied. The switches were then treated with a final relaxing process: commercial relaxer cream applied for 30 minutes, rinsed for 1 minute, lathered for 30 seconds with commercial neutralising shampoo. One set was then allowed to dry as above, no further action was taken. The remaining sets of 4 switches were then treated to a further post treatment of conditioner as exemplified in the tables below.

To each switch ImI of conditioner was applied, which was manipulated into the switch using a gloved forefinger and thumb rubbing motion. Once the conditioner was distributed throughout the switch the switches were left at ambient conditions for 1 minute prior to being rinsed as previously. After rinsing all the treated switches were then equilibrated and dried in controlled condition 25°C/50% RH overnight prior to beginning weighed. The switches were then mounted into a combing rig and the rig was set to comb on programmed to comb the switches for 5400 stokes at 350. The switches were then removed and repositioned. On remounting the switches they were flipped over and relocated in a different position. This was repeated until the switches had been combed for 32,400 stokes. The final weight was recorded and % lost calculated.

Table 1 Relaxer formulation

Sodium hydroxide 2.2%

Petrolatum, 15%

Mineral oil, 15%

Cetearyl Alcohol, 6%

Polysorbate 60, 4%

Laneth-15, 2%

Peg-60 lanolin, 2%

Steareth-20, 2%

Tea-coco-hydrolysed protein, 0.5%

Peg -150 Stearate, 0.2%

Fragrance. 0.1%

Water to 100

Table 2 Conditioner Formulation Example 1

1 is a lmm dimethiconol emulsion with a polyoxytheylene polyoxypropylene copolymer.

2 is amodimethicone 2 mole % N with a particle size of 50 nm.

Table 3 Conditioner Formulation Example A

Table 4 Conditioner Formulation Example B

Example 1 versus Example A Example 1

Example 1 versus Example B

Examples of the invention give enhanced protection against weight loss, broken fibres and split ends.

Claims

1. A hair relaxing kit comprising two compositions: i) the first composition comprising a hair relaxing composition; and i) the second composition comprising emulsified particles of an amino functional silicone of general formula:

Si(CH₃)₃ - O - [Si(CH₃)₂ - O - ]x - [Si (CH₃) (R - NH - CH₂CH₂ NH₂) - O -]y - Si (CH₃) ₃

2. A kit according to claim 1, in which the mole percent amino functionality of the amino functional silicone of ranges from 1 to 8.0 mole %.

3. A kit according to composition according to any preceding claim, in which the viscosity of the emulsified non-amino functionalised silicone itself is at least 60,000 cst.

4. A kit according to any preceding claim in which the second composition further comprises a cationic conditioning surfactant.

5. A kit according to any preceding claim in which the relaxer composition i) comprises at least one hydroxide ion generator which generates hydroxide ions in situ.

6. A method for relaxing hair comprising the following steps : i) applying to the hair for a sufficient period of time to lanthionize the hair a relaxer composition; ii) terminating the lanthionization process; iii) applying to the hair a post-lanthionization composition comprising an amino functional silicone of general formula:

wherein x + y is a number from about 50 to about 500, and wherein R is an alkylene group having from 2 to 5 carbon atoms; in which the amino functional silicone has a mole % amine functionality of at least 1 mole % and a and a non-amino functionalised silicone.