HAIR TREATMENT PROCESS

Abstract

HAIR TREATMENT PROCESS The present invention relates to a hair treatment process comprising the application to the hair of a composition comprising: a) at least one superabsorbent polymer selected from starches grafted with an acrylic polymer; and b) at least one salt of polyacrylic acid. The present invention also relates to the use of a combination of at least one superabsorbent polymer selected from starches grafted with an acrylic polymer and at least one salt of polyacrylic acid for volumizing hair. Figure for abstract: none

Description

Title of the invention: HAIR TREATMENT PROCESS Technical field

[0001] The present invention relates to a process for treating hair. STATE OF THE ART

[0002] Consumers, especially Chinese consumers, are seriously concerned about oily hair. Sebum is first secreted by the sebaceous gland on the scalp, and then can migrate along the hair fibers from root to tip by gravity, friction, and capillary force. This is a vicious circle: the closer the hair fibers get, the more capillary force accelerates the migration of liquid sebum along the fibers.

[0003] Excessive sebum secretion leads to many unwanted problems in the scalp, oxidation by reactive oxidant species or metabolization by scalp sebum microflora can trigger inflammatory factors, which can lead to long-term dysfunction, such as scalp sensitivity, dandruff or even hair loss. While its migration on the hair can make the hair flat, non-plump, difficult to style or stringy (hair sticks together), give the hair a shiny, greasy appearance and make it smell bad.

[0004] Excessive sebum secretion on the scalp makes hair greasy and alters its appearance, particularly its volumized appearance.

[0005] In addition, the presence of sebum reduces the perceived freshness on the scalp.

[0006] There are many products developed to solve the problems caused by excess sebum.

[0007] For example, US5137715A discloses a hair shampoo-conditioner composition consisting essentially of: (a) from about 1% to about 20% by weight of an anionic cleansing surfactant; (b) from about 0.1% to about 2.5% by weight of a substantially uncrosslinked polymeric amidoamine; and (c) a suitable carrier comprising water; wherein the composition has a pH in the range of from about 2.5 to less than 7.

[0008] However, many products on the market are not effective against excess sebum, so they cannot give hair a volumized appearance.

[0009] It is therefore desirable to have an effective solution against excess sebum, capable of reducing the problems caused by abundant sebum and giving the hair a voluminous appearance. Summary of the invention

[0010] An object of the present invention is therefore to develop a hair treatment process, which can reduce the problems caused by abundant sebum and give the hair a volumized appearance.

[0011] Thus, according to a first aspect, the present invention provides a hair treatment process comprising the application to the hair of a composition comprising: a. at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer; and b. at least one polyacrylic acid salt.

[0012] The inventors have discovered that the process according to the present invention can effectively combat sebum and make hair volumized.

[0013] According to a second aspect, the present invention proposes a use of a combination of at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer and at least one polyacrylic acid salt for volumizing the hair.

[0014] Other subjects and characteristics, aspects and advantages of the present invention will become even more apparent from the detailed description and examples which follow. DETAILED DESCRIPTION OF THE INVENTION

[0015] According to the first aspect, the composition used in the process of the present invention comprises: a. at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer; and b. at least one polyacrylic acid salt. Superabsorbent polymer

[0016] The composition used in the process of the present invention comprises at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer.

[0017] The term "superabsorbent polymer" is intended to mean a polymer which is capable in its dry form of spontaneously absorbing at least 20 times its own weight of aqueous fluid, in particular water, and in particular distilled water. Such superabsorbent polymers are described in the book "Absorbent Polymer Technology, Studies in Polymer Science 8" by L. Brannon-Peppas and R. Harland, published by Elsevier, 1990.

[0018] Advantageously, said superabsorbent polymer is chosen from starches grafted with an acrylic homo- or copolymer, particularly starches grafted with sodium polyacrylate. Specifically, the acrylic polymer may be a homopolymer or a copolymer, particularly sodium polyacrylate.

[0019] These polymers have a high capacity for absorbing and retaining water and aqueous fluids. After absorption of the aqueous liquid, the polymer particles thus engorged with aqueous liquid remain insoluble in the aqueous liquid and thus retain their individualized particulate state.

[0020] The superabsorbent polymer may have a water absorption capacity ranging from 20 to 2000 times its own weight (i.e. from 20 g to 2000 g of water absorbed per gram of absorbent polymer), preferably from 30 to 1500 times and even better from 50 to 1000 times. These water absorption characteristics are defined under standard conditions of temperature (25 °C) and pressure (760 mmHg, i.e. 100,000 Pa) and for distilled water. The value of water absorption capacity of a polymer can be determined by dispersing 0.5 g of polymer(s) in 150 g of water solution, waiting for 20 minutes, filtering the unabsorbed solution through a 150 qm filter for 20 minutes and weighing the unabsorbed water.

[0021] The superabsorbent polymer used in the composition of the invention is in the form of particles. Preferably, the superabsorbent polymer has, in dry or non-hydrated form, an average size less than or equal to 100 qm and preferably less than or equal to 50 qm, for example ranging from 1 to 100 qm, preferably from 5 to 50 qm and better still from 7 to 30 qm.

[0022] The average particle size corresponds to the mass average diameter (D50) measured by laser granulometric analysis or other equivalent method known to those skilled in the art. These particles, once hydrated, swell while forming soft particles having an average size which can range from 10 qm to 2000 qm.

[0023] Such polymers are known for their gelling properties and are generally used in pre-swollen form in aqueous phase.

[0024] According to a particular embodiment of the invention, the super-absorbent polymer(s) used comprise(s) from 85% to 95% by weight of sodium polyacrylate and from 5% to 15% by weight of starch. Preferably, it(they) is / are made up of 90% by weight of sodium polyacrylate and 10% by weight of starch.

[0025] According to a particular embodiment of the invention, the number-average molecular weight of the superabsorbent polymer(s) used is greater than 1000 daltons.

[0026] Mention may in particular be made of starches grafted with an acrylic polymer and in particular with sodium polyacrylate, such as those sold under the name Sanfresh ST-100MC by Sanyo Chemical Industries or Makhnousse 25, Makhnousse 12 or Ma-kimousse 7 by Daito Kasei (INCI name: Sodium polyacrylate starch).

[0027] The superabsorbent polymers used in the present invention may be crosslinked or non-crosslinked.

[0028] The superabsorbent polymers used in the present invention are preferably starches grafted with an acrylic homo- or copolymer, in particular sodium polyacrylate, which is in particulate form.

[0029] Preferably, the superabsorbent polymer is chosen from starches grafted with an acrylic homopolymer, preferably in the form of particles having an average size (or an average diameter) less than or equal to 100 microns, more preferably in the form of particles, so that the hair will not stick to each other, thus reducing the migration of sebum induced by capillary force and will then have a voluminous appearance.

[0030] With the presence of the superabsorbent polymers, the composition of the present invention can provide a non-wet and quick drying feel.

[0031] On the other hand, since superabsorbent polymers have good affinity with the skin, this results in good fixation of the absorption beads, which can provide good sebum control efficiency.

[0032] Advantageously, the superabsorbent polymer is present in the composition used in the process according to the present invention in an amount ranging from 0.01% by weight to 5% by weight, preferably ranging from 0.1% by weight to 3% by weight, more preferably ranging from 0.1% by weight to 1% by weight, most preferably ranging from 0.2% by weight to 0.8% by weight, relative to the total weight of the composition. Polyacrylic acid salts

[0033] The composition used in the process of the present invention comprises at least one polyacrylic acid salt.

[0034] Suitable polyacrylic acid salts for use in the present invention include, but are not limited to, metal salts of polyacrylic acid.

[0035] The polyacrylic acid salt can be partially or completely neutralized.

[0036] The acrylic monomers of the polyacrylic acid salts according to the invention can be neutralized in a proportion of 90% to 100%.

[0037] Examples thereof include sodium, potassium, lithium and ammonium salts of polyacrylic acid.

[0038] The most preferred salt of polyacrylic acid is sodium polyacrylate.

[0039] Sodium polyacrylates are acrylic homopolymers in partially or fully neutralized form, and they are hydrophilic.

[0040] According to the invention, the expression “hydrophilic polymer” designates a non-amphiphilic polymer which is soluble and dispersible in water.

[0041] In a preferred embodiment, said polyacrylate is sodium polyacrylate designated by CAS number 9003-04-7. Sodium polyacrylate is for example COSMEDIA SP sold by BASF or COVACRYL® MV60 sold by SENSIENT.

[0042] Sodium polyacrylate sold under the name Cosmedia SP® contains 90% dry matter and 10% water.

[0043] Advantageously, the polyacrylic acid salt is present in the composition used in the process according to the present invention in an amount ranging from 0.01% by weight to 5% by weight, preferably ranging from 0.1% by weight to 3% by weight, more preferably ranging from 0.1% by weight to 1% by weight, most preferably ranging from 0.2% by weight to 0.8% by weight, relative to the total weight of the composition.

[0044] The inventors of the present invention have discovered that a combination of at least one superabsorbent polymer selected from starches grafted with an acrylic polymer and at least one polyacrylic acid salt can give a good sebum control effect and volumize the hair.

[0045] It is preferred that the weight ratio of superabsorbent polymer to polyacrylic acid salt be from 1:4 to 4:1, so that a good balance of suspension required by the composition and preferred capillary feel can be achieved. Aqueous phase

[0046] The composition used in the process of the present invention may further comprise a continuous aqueous phase.

[0047] Said aqueous phase is preferably present in an amount ranging from 50% by weight to 99.5% by weight, more preferably from 70% by weight to 99.5% by weight, relative to the total weight of the composition.

[0048] The aqueous phase comprises water.

[0049] Water is preferably present in the composition used in the process of the present invention in an amount ranging from 50% by weight to 99.5% by weight, preferably from 60% by weight to 99.5% by weight, relative to the total weight of the composition.

[0050] Optionally, the continuous aqueous phase comprises one or more organic solvents miscible with water (at room temperature of 25°C) such as, for example, monoalcohols having from 2 to 6 carbon atoms such as ethanol, isopropanol; polyols having from 2 to 20 carbon atoms, preferably from 2 to 10 carbon atoms, and preferentially having from 2 to 6 carbon atoms, such as glycerin, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, caprylyl glycol, dipropylene glycol, diethylene glycol; glycol ethers (having in particular from 3 to 16 carbon atoms) such as mono-, di- or tri-propylene glycol (Ci-C4)alkyl ethers, mono-, di- or tri-ethylene glycol (Ci-C4) alkyl ethers and mixtures thereof.

[0051] In some embodiments, the aqueous phase comprises one or more miscible organic solvents chosen from monoalcohols having from 2 to 6 carbon atoms; polyols having from 2 to 20 carbon atoms; glycol ethers having from 3 to 16 carbon atoms, and mixtures thereof, more preferably chosen from ethanol, glycerin and mixtures thereof.

[0052] Optionally, the composition used in the process of the present invention comprises 0.1% by weight to 80% by weight of a water-miscible organic solvent mentioned above, based on the total weight of the composition.

[0053] In certain embodiments, the continuous aqueous phase comprises ethanol in an amount ranging from 0.1% by weight to 50% by weight, preferably from 1% by weight to 45% by weight, more preferably from 5% by weight to 40% by weight, even more preferably ranging from 10% by weight to 40% by weight, relative to the total weight of the composition. Cosmetic active ingredients

[0054] Optionally, the composition used in the process of the present invention comprises one or more additional active ingredients for revitalizing keratinous materials.

[0055] A person skilled in the art can select the amount of additional active ingredients depending on the desired objective. Adjuvants

[0056] The composition used in the process according to the present invention may also comprise additional adjuvants, such as perfumes, preservatives, etc.

[0057] A person skilled in the art can choose the amount of additional adjuvants so that it does not have a negative impact on the final use of the composition according to the present invention.

[0058] According to a preferred embodiment, the composition used in the process of the present invention comprises, relative to the total weight of the composition:

[0059] a) from 0.2% by weight to 0.8% by weight of starches grafted with sodium polyacrylate; and

[0060] b) from 0.2% by weight to 0.8% by weight of sodium polyacrylate. Preparation and use

[0061] The composition used in the process according to the present invention can be prepared by mixing ingredients a) and b), as essential ingredients, as well as additional ingredient(s), as explained above.

[0062] With the use of said composition, the process according to the present invention can reduce the problems caused by abundant sebum and give the hair a volumized appearance. EXAMPLES

[0063] The following examples are given as non-limiting illustrations of the present invention.

[0064] The main raw materials used, their trade names and suppliers are listed in Table 1.

[0065] [Tables 1] INCI Name Trade Name Supplier SODIUM POLY-ACRYLATE STARCH MAKIMOUSSE™ 25 DAITO KASEI KOGYO SODIUM POLY-ACRYLATE COVACRYL® MV60 SENSIENT ETHANOL ETHANOL ABSOLU ANHUI ANTE FOOD CARBOMER POLYMER CARBOPOL® ULTREZ 10 LUBRIZOL VP / VA COPOLYMER LUVISKOL® VA 64 POWDER BASF

[0066] Inventive Examples 1 and 2 and Comparative Examples 1 to 4

[0067] The compositions of inventive examples (EI) 1 and 2 and comparative examples (CE) 1 to 4 were prepared with the components listed in Table 2 (the contents are expressed as percentages by weight relative to the total weight of each composition, unless otherwise indicated):

[0068] [Tables2] Components El. 1 EI.2 EC. 1 EC. 2 EC. 3 EC. 4 SODIUM POLYACRYLATE STARCH 0.3 0.3 0 0 0.3 0 SODIUM POLYACRYLATE 0.3 0.3 0 0 0 0.3 ETHANOL 30 0 30 30 30 30 CARBOMER 0 0 0.6 0 0 0 VP / VA COPOLYMER 0 0 0 0.6 0 0 WATER QS100 QS100 QS100 QS100 QS100 QS100

[0069] The compositions of inventive examples 1 and 2 are compositions used in the process according to the present invention.

[0070] The compositions of comparative examples 1 and 2 do not comprise at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer and at least one polyacrylic acid salt.

[0071] The composition of comparative example 3 does not comprise at least one polyacrylic acid salt.

[0072] The composition of comparative example 4 does not comprise at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer.

[0073] Preparation procedure:

[0074] Each composition was prepared as follows, taking the composition of inventive example 1 as an example: 1. adding water to a main container, 2. adding sodium polyacrylate starch and sodium polyacrylate with stirring; and 3. Adding ethanol to the main container while stirring to obtain a homogeneous composition.

[0075] Evaluation:

[0076] The anti-sebum migration effect and the volumized appearance of the hair provided by each composition prepared above were evaluated. Anti-sebum migration

[0077] Strands of 100% white hair were used for this test; a reset pre-wash was performed with a standard shampoo. The compositions of inventive examples 1 and 2 and comparative examples 1 to 4 were evaluated in this test.

[0078] 2.5 g of a tested composition was applied to each strand, each lock of hair was then fixed on a support.

[0079] After preheating to 40°C, 100 qL of artificial sebum was collected using an automatic micropipette and applied to the end of a spatula.

[0080] The lock of hair was then wound onto a rigid ruler, and the artificial sebum was spread evenly from the spatula over a calibrated length of 3 cm, which was separated by 1.5 cm from the support.

[0081] A timer was started and the sebum front was observed after 20 minutes, 40 minutes, 2 hours, 24 hours and 48 hours. The migration distance was measured and recorded at these times. Hair volumized appearance

[0082] 6 g of natural hair strands were used for this test; a pre-wash of reset was performed with a standard shampoo. The compositions of Inventive Examples 1 and 2 and Comparative Examples 1 to 4 were evaluated in this essay.

[0083] 0.3 g of oleic acid was applied to each strand, then 1.5 g of a composition testing was applied to each strand.

[0084] After drying, each strand was combed five times and the volume of each strand was observed and rated from 1 to 5 according to the following criterion.

[0085] 5: very good; separate and distinct appearance of hair fibers.

[0086] 4: overall good; very good volumized appearance of the hair, fibers not clumpy completely separated.

[0087] 3: acceptable; good voluminous appearance of hair, with some fibers sticky.

[0088] 2: slightly poor and unacceptable; hair lacks volume with sticky fibers.

[0089] 1: poor, unacceptable, fibers sticking together, stringy appearance of the hair.

[0090] The sebum migration distance and the average scores for the volumized appearance of the hair provided by the compositions of Inventive Examples 1 and 2 and Comparative Examples 1 to 4 have been summarized in Table 3.

[0091] [Tables3] Properties El. 1 El. 2 EC. 1 EC. 2 EC. 3 EC. 4 Sebum migration distance (cm) 20 min 5.1 5.3 5.5 5.5 5.4 5.7 40 min 5.5 5.7 6.0 6.2 6.0 6.3 2h 5.8 6.3 6.6 6.7 6.7 6.9 24 h 6.4 6.8 7.2 7.5 7.3 7.6 48 h 6.9 7.4 9.0 8.2 8.2 8.4 Rating for hair volumized appearance 5 4 2 2 3 3

[0092] It can be seen from Table 3 that the process using each composition of inventive examples 1 and 2 results in good anti-sebum performance and can give the hair a good volumized appearance.

Claims

Claims

1. A process for treating hair comprising applying to the hair a composition comprising: a) at least one superabsorbent polymer selected from starches grafted with an acrylic polymer; and b) at least one polyacrylic acid salt.

2. Process according to claim 1, wherein the superabsorbent polymer is selected from starches grafted with an acrylic homo- or copolymer, in particular starches grafted with sodium polyacrylate.

3. A process according to any one of claims 1 to 2, wherein the polyacrylic acid salt is selected from metal salts of polyacrylic acid, preferably the polyacrylic acid salt is selected from sodium, potassium, lithium and ammonium salts of polyacrylic acid, more preferably the polyacrylic acid salt is sodium polyacrylate.

4. A process according to any one of claims 1 to 3, wherein the weight ratio of superabsorbent polymer to polyacrylic acid salt is 1:4 to 4:

1.

5. A process according to any one of claims 1 to 4, wherein the composition further comprises a continuous aqueous phase.

6. A process according to claim 5, wherein the aqueous phase comprises water, preferably in an amount ranging from 50% by weight to 99% by weight, preferably from 60% by weight to 99% by weight, relative to the total weight of the composition.

7. Process according to any one of claims 5 to 6, wherein the continuous aqueous phase comprises one or more water-miscible organic solvents, preferably chosen from monoalcohols having from 2 to 6 carbon atoms; polyols having from 2 to 20 carbon atoms; glycol ethers having from 3 to 16 carbon atoms, and mixtures thereof, more preferably chosen from ethanol, glycerin and mixtures thereof, preferably in an amount ranging from 0.1% by weight to 80% by weight, relative to the total weight of the composition.

8. A process according to claim 6, wherein the continuous aqueous phase comprises ethanol in an amount ranging from 0.1% by weight to 50% by weight, preferably from 1% by weight to 45% by weight, plus preferably from 5% by weight to 40% by weight, even more preferably ranging from 10% by weight to 40% by weight, relative to the total weight of the composition.

9. A process according to claim 1, wherein the composition comprises, relative to the total weight of the composition: a) from 0.2% by weight to 0.8% by weight of starches grafted with sodium polyacrylate; and b) from 0.2% by weight to 0.8% by weight of sodium polyacrylate

10. Use of a combination of at least one superabsorbent polymer chosen from starches grafted with an acrylic polymer and at least one polyacrylic acid salt for volumizing hair.