WO2025061410A1

WO2025061410A1 - Cosmetic composition comprising liquid crystal phase

Info

Publication number: WO2025061410A1
Application number: PCT/EP2024/073629
Authority: WO
Inventors: Xiangrong HUANG; Xiaoke Li; Weining LIU
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV; Conopco Inc
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV; Conopco Inc
Priority date: 2023-09-21
Filing date: 2024-08-23
Publication date: 2025-03-27
Anticipated expiration: 2026-03-21

Abstract

The present invention is in the field of cosmetic compositions, in particular, compositions which can provide sweat management benefit. Disclosed is a cosmetic composition comprising: (i)ethanol; (ii)a cationic surfactant which is ethyl lauroyl arginate HCl; (iii)amphiphilic material being a substance or mixture of substances which forms, upon contact with sweat, a water-insoluble liquid crystal phase of greater than one dimensional periodicity; wherein the weight ratio of amphiphilic material to said cationic surfactant is from 60:1 to 1:2.

Description

COSMETIC COMPOSITION COMPRISING LIQUID CRYSTAL PHASE

Field of the invention

The present invention is in the field of cosmetic compositions, particularly compositions which can provide sweat management benefit, which is capable of preventing sweat from rapidly being released, absorbing or managing excess sweat.

Background of the invention

The present invention relates to cosmetic compositions, particularly compositions which can provide sweat management benefit. The compositions are used to control or manage moisture (or excess sweat) on the skin surface upon topical application of the compositions to the body, particularly to the underarm regions of the human body viz. the axilla, and sometimes even on the upper part of the body near the chest. Such composition can help prevent sweat from rapidly being released, absorb or manage excess sweat on skin surface upon topical application of the compositions to the body.

Summary of the invention

The present inventors have surprisingly observed that a cosmetic composition comprising ethanol, specific cationic surfactant, and an amphiphilic material which forms, upon contact with perspiration, a water-insoluble liquid crystal phase of greater than one dimensional periodicity can lead to improved sweat management benefit. In addition to being stable, the composition is capable of forming preci pitation/aggregation when they contact with aqueous saline media, which is equivalent to sweat, thereby is capable of preventing sweat from rapidly being released, absorbing or managing excess sweat. In this manner, such composition can control or manage moisture (or excess sweat) on the desired skin surface.

In accordance with a first aspect is disclosed a cosmetic composition comprising:

(i) ethanol;

(ii) a cationic surfactant which is ethyl lauroyl arginate HCI;

(iii) amphiphilic material being a substance or mixture of substances which forms, upon contact with sweat, a water-insoluble liquid crystal phase of greater than one dimensional periodicity; wherein the weight ratio of amphiphilic material to said cationic surfactant is from 60:1 to 1 :2.

In accordance with a second aspect is disclosed a method of preventing sweat from rapidly being released, absorbing or managing excess sweat comprising a step of topical application of the composition of the first aspect on to the desired skin surface.

In accordance with a third aspect is disclosed use of the composition of the first aspect for preventing sweat from rapidly being released, absorbing or managing excess sweat on desired skin surface.

All other aspects of the present invention will more readily become apparent upon considering the detailed description and examples which follow.

Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use may optionally be understood as modified by the word “about”.

All amounts are by weight of the composition, unless otherwise specified.

It should be noted that in specifying any ranges of values, any particular upper value can be associated with any particular lower value.

For the avoidance of doubt, the word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of”. In other words, the listed steps or options need not be exhaustive.

The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy. Where a feature is disclosed with respect to a particular aspect of the invention (for example a composition of the invention), such disclosure is also to be considered to apply to any other aspect of the invention (for example a method of the invention) mutatis mutandis.

Detailed description of the invention

By “A cosmetic composition” as used herein, is meant to include a composition for topical application to the skin of mammals, especially humans. Such a composition is preferably of the leave-on type. By a leave-on composition is meant a composition that is applied to the desired skin surface and left on for one minute to 24 hours after which it may be wiped or rinsed off with water, usually during the regular course of personal washing. The composition may also be formulated into a product which is applied to a human body for improving the appearance, cleansing, odor control or general aesthetics. The composition of the present invention can be in the form of a liquid, lotion, cream, gel or stick form and may be delivered through a roll-on device or using an aerosol can which contains a propellant. “Skin” as used herein is meant to include skin on any part of the body (e.g., neck, chest, back, arms, underarms, hands, legs, buttocks and scalp) especially the underarms. The cosmetic composition in accordance with the present invention is sweat management composition which is used for providing sweat management benefit which is preventing sweat from rapidly being released, absorbing or managing excess sweat on the skin surface.

Herein, “water-insoluble” means having a solubility in water of less than 0.1% by weight (at 37°C).

Herein, an “amphiphilic material” is a material defined by having both hydrophilic and hydrophobic portions in its structure.

Herein, a “volatile silicone” is a silicone having a vapour pressure of greater than 1 Pa at 25°C.

Cationic surfactant The cationic surfactant in accordance with this invention is ethyl lauroyl arginate HCI.

It is preferred that the composition comprises from 0.1 to 25% of the cationic surfactant, more preferably from 0.5 to 15%, furthermore preferably from 0.5 to 10% by weight of the composition.

Amphiphilic material

The amphiphilic material is a substance or mixture of substances which forms, upon contact with sweat, a water-insoluble liquid crystal phase of greater than one dimensional periodicity. The amphiphilic material is a substance or mixture of substances capable of forming phases as described immediately above, on contact with sweat on the skin of the human body, at body temperature (37°C) and preferably at from 25°C to 37°C.

It is essential to have sufficient of the amphiphilic material present in the composition to achieve an acceptable benefit when the composition is applied to the skin of the human body.

The amphiphilic material must be insoluble in water but must also pass through physical phases on the addition of water ultimately resulting in a liquid crystalline phase of greater than one dimensional periodicity. Such phases include cubic liquid crystal structures, which have long-range periodicity in three dimensions and hexagonal crystal structures, which have long-range periodicity in two dimensions.

Herein, reference to the formation of a liquid crystalline phase of greater than one dimensional periodicity on contact with sweat should understood to refer, in particularly, to such contact at close to body temperature, e.g. at from 30 to 35°C.

According to a preferred embodiment of the invention, the amphiphilic material is one which physically swells as it forms the liquid crystal structure on contact with sweat, hence providing the desired benefit. Conveniently, the structure of the active can be determined by standard X-ray scattering techniques.

Preferred amphiphilic materials comprise a lipid substances, in particular glycerol monooleate or glycerol monolaurate. It is especially preferred that such lipid is used in combination with a material selected from the group consisting of: oleic acid, oleyl alcohol, isostearyl alcohol, stearyl alcohol and 1 -mono-isostearyl glyceryl ether.

Preferred mixtures of amphiphilic materials may be selected from:

1. Oleyl alcohol and glycerol monolaurate at a weight ratio of from 24: 76 to 26: 74;

2. Oleyl alcohol and triethylene glycol mono hexadecyl ether at a weight ratio of from 5: 95 to 13: 87;

3. Ceramides (from bovine brain) and glycerol monooleate at a weight ratio of from 5: 95 to 30: 70;

4. Oleyl alcohol and hexadecyl trimethyl ammonium chloride at a weight ratio of from 24: 76 to 26: 74;

5. Cyclohexane and didodecyldimethylammonium chloride at a weight ratio of 23.5: 76.5;

6. Lysozyme and glyceryl monooleate at a weight ratio of 20: 80;

7. Diethylene glycol mono oleyl ether and pentaethylene glycol mono oleyl ether at a weight ratio of from 66: 34 to 76: 24;

8. Isostearyl alcohol and glyceryl monolaurate at a weight ratio of from 21 : 79 to 25: 75;

9. Oleyl alcohol and glyceryl monolaurate at a weight ratio of from 28: 72 to 44: 56;

10. Oleyl alcohol and triethylene glycol mono hexadecyl ether at a weight ratio of from 15: 85 to 25: 75;

11. Dodecyltrimethylammonium chloride and oleic acid at weight ratio of from 29 to 71 ;

12. Oleyl alcohol and distearyldimethylammonium chloride at a weight ratio of from 40 to 60; 13. Oleic acid and distearyldimethylammonium chloride at a weigt ratio of from 40 to 60;

14. Oleic acid and lecithin at a weight ratio of from 34: 66 to 50: 50;

15. Glyceryl monooleate and tetradecane at a weight ratio of 90: 10;

16. Glyceryl monooleate and hexadecane at a weight ratio of from 95: 5 to 65: 35;

17. Diethyleneglycol mono-oleyl ether and pentaethylene glycol mono--oleyl ether at a weight ratio of 80: 20;

18. Glyceryl monooleate and silicone oil (DC 246 ex Dow Corning) at a weight ratio of from 87: 13 to 80: 20;

19. Oleic acid and alkyl polyglucoside (APG 600 ex Henkel) at a weight ratio of from 50: 50 to 60: 40;

20. Oleyl alcohol and alkyl polyglucoside (APG 600 ex Henkel) at a weight ratio of from 50: 50 to 60: 40;

21. Isostearyl alcohol and glyceryl monolaurate at a weight ratio of from 25: 75 to 45: 55;

22. Glyceryl monooleate and batyl alcohol at a weight ratio of 95: 5;

23. Glyceryl monooleate and chimyl alcohol at a weight ratio of 95 to 5; and

24. Glyceryl monooleate and 1-mono-isostearyl glyceryl ether at a weight ratio of 95: 5;

It is particularly preferred that the amphiphilic material forms cubic or hexagonal phase on contact with sweat, more preferably forms hexagonal phase.

Particularly preferred mixtures of amphiphilic materials that form cubic or hexagonal phase on contact with sweat and are selected from:

1. Oleyl alcohol and glyceryl monolaurate at a weight ratio of from 28: 72 to 44: 56;

2. Oleyl alcohol and triethylene glycol mono hexadecyl ether at a weight ratio of from 15: 85 to 25: 75;

3. Glyceryl monooleate and silicone oil (DC 246 ex Dow Corning) at a weight ratio of from 87: 13 to 80: 20;

4. Oleyl alcohol and alkyl polyglucoside (APG 600 ex Henkel) at a weight ratio of from 50: 50 to 60: 40 and 5. I sostearyl alcohol and glyceryl monolaurate at a weight ratio of from 25: 75 to 45: 55.

In most preferred embodiments, the amphiphilic material comprises or is a mixture of isostearyl alcohol and glycerol monolaurate and especially when used at a weight ratio of from 25: 75 to 45: 55.

Cosmetic compositions according to the present invention are preferably free from aluminium or zirconium antiperspirant salts.

The content of amphiphilic material in the total composition is preferably at least 5%, more preferably at least 10%, furthermore preferably at least 12% and most preferably at least 15% by weight of the composition.

It is preferred that the composition comprises a volatile silicone. The volatile silicone and its level of incorporation serves to reduce potential irritation and/or promote the good sensory properties of the composition.

The content of volatile silicone in the total composition, is preferably from 10% to 50%, more preferably from 15% to 50% most preferably from 15% to 45% by weight of the composition.

It is preferred that the volatile silicone comprises greater than 90% by weight of, or consists of siloxanes having from 2 to 6 silicone atoms, arranged in either a cyclic or linear fashion.

Linear siloxanes have the general formula: Me3SiO(Me2SiO)_nSiMe3, where Me = methyl group (-CH₃).

When n = 0, the siloxane is hexamethyldisiloxane.

When n = 1 , the siloxane is octamethyltrisiiloxane.

When n = 2, the siloxane is decamethyltetrasiloxane.

When n = 3, the siloxane is dodecamethylpentasiloxane. It is particularly preferred that the volatile silicone comprises greater than 90% by weight of, or consists of, siloxanes selected from the group consisting of hexamethyldisiloxane, octamethyltrisiiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane and decamethylcyclopentasiloxane.

It is especially preferred that the volatile silicone comprises greater than 90% by weight of, or consists of, siloxanes selected from the group consisting of hexamethyldisiloxane, octamethyltrisiiloxane, decamethyltetrasiloxane and decamethyl cyclopentasiloxane.

Ethanol

The purpose of the ethanol is principally to solubilise the amphiphilic material.

The content of ethanol in the total composition is preferably at least 5%, more preferably at least 10%, furthermore preferably at least 12% and most preferably at least 15% by weight of the composition. It is preferred the composition comprises from 10 to 95% of ethanol, more preferably from 20 to 80%, furthermore preferably from 30 to 60% by weight of the composition.

The weight ratio of ethanol to amphiphilic material must be at least 7: 3 or, more precisely, 70: 30. More preferably this weight ratio is at least 71 : 29 and most preferably at least 72: 28.

In accordance with the present invention, the weight ratio of amphiphilic material to said cationic surfactant is from 60:1 to 1:2, preferably from 30:1 to 1 :1 , more preferably from 15:1 to 1:1 , more preferably from 10:1 to 1:1. pH of compositions

The pH of the composition of the present invention is from 3 to 10, preferably from 4 to 8.5, more preferably 5 to 8.

Other ingredients Other components commonly included in cosmetic compositions may also be incorporated in the compositions of the present invention. Such components include skin care agents such as emollients, humectants and skin barrier promoters; skin appearance modifiers such as skin lightening agents and skin smoothing agents; antimicrobial agents, in particular organic anti-microbial agents, and preservatives.

The composition may include skin actives selected from a group consisting of alphahydroxy acids, acetyl methionine, mandelic acid, methylxanthines, alkaloids and caffeine.

The compositions of the invention are applied cosmetically and topically to the skin, broadly speaking, by one of two methods. Different consumers prefer one method or the other. In one method, sometimes called a contact method, the composition is wiped across the surface of the skin, depositing a fraction of the composition as it passes. In the second method, sometimes called the non-contact method, the composition is sprayed from a dispenser held proximate to the skin, often in an area of about 10 to 20 cm². The spray can be developed by mechanical means of generating pressure on the contents of a dispenser, such as a pump or a squeezable sidewall or by internally generated pressure arising from a fraction of a liquefied propellant volatilizing, the dispenser commonly being called an aerosol.

There are broadly speaking two classes of contact compositions, one of which is liquid and usually applied using a roll-on dispenser or possibly absorbed into or onto a wipe, and in the second of which the active is distributed within a carrier liquid that forms a continuous phase that has been gelled. In one variation, the carrier fluid comprises a solvent for the active and in a second variation, the active remains a particulate solid that is suspended in an oil, usually a blend of oils.

It is preferred that the composition of the invention is in the form of a cream, a spray, a firm solid, a soft solid, wipes or is an emulsion packaged in a roll-on applicator, more preferably in the form of lotion, spray, firm solid, soft solid, cream, or is an emulsion packaged in a roll-on applicator. It is preferred that, when said composition is a spray it comprises a propellant and the composition is in the form of an aerosol.

Further preferably, the composition of the invention is in the form of a roll-on or an aerosol product.

Wipes here are intended for applying the composition. Wipes are usually made of materials such as polyester, polypropylene, cotton, wood pulp, or rayon fibers formed into sheets. They may be packaged individually, or in small or bulk packaging. They are usually moistened with water, or ethanol or other ingredients that help them work. They may contain other ingredients, such as preservatives to prevent the growth of bacteria and molds.

The compositions in accordance with this invention may comprise an antiperspirant active.

The composition is preferably free from antiperspirant active which comprises aluminium or zirconium. It is also preferably free from antiperspirant active which comprises zinc.

Non-aluminum and non-zirconium, non-zinc antiperspirant actives may be present in the composition. Non- aluminum or zirconium, or non-zinc antiperspirant active is preferably selected from glycerol monolaurate plus isostearyl alcohol, chitosan or a salt thereof with a weight average molecular weight of from 250 to 650 kDa, titanium compound chelated by alkanolamine with an acid and a polyhydric alcohol, or cholic acid derivative selected from a hydroxycholic acid or a salt thereof with a multivalent metal salt.

Stick

Many different materials have been proposed as gellants for a continuous oil phase, including waxes, small molecule gelling agents and polymers. They each have their advantages and of them, one of the most popular class of gellants is waxes, partly at least due to their ready availability and ease of processing, including in particular linear fatty alcohol wax gellants. A gelled composition is applied topically to skin by wiping it across and in contact with the skin, thereby depositing on the skin a thin film.

The nature of the film depends to a significant extent on the gellant that is employed. Although wax fatty alcohols have been employed as gellants for many years, and are effective for the purpose of gelling, the resultant product is rather ineffective at improving the visual appearance of skin, and in particular underarm skin, to which the composition has been applied. This problem has been solved by including ameliorating materials for example, di or polyhydric humectants and/or a triglyceride oil.

Stick compositions are usually available in the form of a firm solid or a soft solid. Firm solids, as the name indicates, are harder and can be directly applied by way of an applicator, for example, to the underarms. Soft solids also need an applicator which is similar to the firm solids, the difference being that the soft solids are softer and the applicator needs to be designed in order to permit extrusion of the solids through a cap member comprising plurality of orifices and the extruded composition can then be applied to the underarms.

Roll-on

Liquid compositions that are applicable from a roll-on broadly speaking can be divided into two classes, namely those in which an active is suspended in a hydrophobic carrier, such as a volatile silicone and those in which the active is dissolved in a carrier liquid. The latter has proven to be more popular. There are mainly two sorts of dissolving carrier liquid, namely carriers that are predominantly alcoholic, which is to say the greater part of the dissolving carrier fluid comprises ethanol and the second class in which the carrier liquid is mainly water. The former was very popular because ethanol is a mild bactericide in its own right, but its popularity waned because it stings, especially if the surface onto which the composition has been applied has been damaged or cut, such as can easily arise during shaving or other depilatory actions.

The second class of formulations that is an alternative to alcoholic formulations comprise a dispersion of water-insoluble or very poorly water-soluble ingredients in an aqueous solution of the active. Herein, such compositions will be called emulsions. Roll-on emulsions commonly comprise one or more emulsifiers to maintain a distribution of the water-soluble ingredients.

Aerosol compositions

Further alternatively, the composition of the invention is delivered through an aerosol composition which comprises a propellant in addition to the applicable other ingredients described hereinabove. Commonly, the propellant is employed in a weight ratio to the base formulation of from 95:5 to 5:95. Depending on the propellant, in such aerosol compositions the weight ratio of propellant to base formulation is normally at least 20:80, generally at least 30:70, particularly at least 40:60, and in many formulations, the weight ratio is from 90:10 to 50:50. A weight ratio range of from 70:30 to 90:10 is sometimes preferred.

Propellants herein generally are one of three classes; (i) low boiling-point gasses liquified by compression, (ii) volatile ethers and (iii) compressed non-oxidising gases.

Class (i) is conveniently a low boiling-point material, typically boiling below -5°C, and often below -15°C, and in particular, alkanes and/or halogenated hydrocarbons. This class of propellant is usually liquefied at the pressure in the aerosol canister and evaporates to generate the pressure to expel the composition out of the canister. Examples of suitable alkanes include particularly propane, butane or isobutane. The class (ii) of propellant comprises a very volatile ether of which the most widely employed ether hitherto is dimethyl ether. This propellant can advantageously be employed at relatively low weight ratio of propellant to base formulation, for example to as low as 5:95. It can also be employed in admixture with, for example, compressible/liquefiable alkane gasses. The class (iii) of propellant comprises compressed non-oxidising gasses, and in particular carbon dioxide or nitrogen. Inert gases like neon are a theoretical alternative.

The composition of the present invention can comprise a wide range of other optional components. The CTFA Personal Care Ingredient Handbook, Second Edition, 1992, which is incorporated by reference herein in its entirety, describes a wide variety of non-limiting personal care and pharmaceutical ingredients commonly used in the skin care industry, which are suitable for use in the compositions of the present invention. Examples include: antioxidants, binders, biological additives, buffering agents, colorants, thickeners, polymers, astringents, fragrance, conditioners, exfoliating agents, pH adjusters, other than the ones already discussed earlier, preservatives, natural extracts, essential oils, skin sensates, skin soothing agents, and skin healing agents.

A preservative is a preferred additional component in compositions of the invention. A preservative serves to reduce or eliminate microbial contamination of compositions of the invention. Preservatives are typically employed at a total level of from 0.05 to 3%, preferably at from 0.1 to 2% and most preferably at from 0.4 to 1%.

Suitable preservatives for use with the present invention include 2-phenoxyethanol, polylysine, iodopropynyl butylcarbamate, C1-C3 alkyl parabens, sodium benzoate, caprylyl glycol and EDTA. Particularly preferred preservatives are 2-phenoxyethanol, iodopropynyl butylcarbamate, sodium benzoate, caprylyl glycol and EDTA and especially preferred are 2-phenoxyethanol and iodopropynyl butylcarbamate.

A preferred additional component of compositions of the invention is a fragrance. Suitable materials include conventional perfumes, such as perfume oils and also include so-called deo-perfumes, as described in EP 545,556 and other publications. Levels of incorporation are preferably up to 4% by weight, particularly from 0.1% to 2% by weight, and especially from 0.7% to 1 .7% by weight.

An antimicrobial deodorant active is a preferred an additional component in compositions of the invention. Such components serve to reduce or eliminate body odour by reducing or otherwise impeding the function of microbes on the skin of the body responsible for malodour generation.

The antimicrobial deodorant active may also be a preservative for the composition.

When employed, the anti-microbial deodorant agent is typically incorporated into the composition at from 0.01% to 3% and particularly at from 0.03% to 0.5%. Preferred anti-microbial deodorant agents have a minimum inhibitory concentration (MIC) of 1 mg. ml^-1 or less, particularly 200 .g.ml'¹ or less, and especially 100 .g.ml'¹ or less. The MIC of an anti-microbial agent is the minimum concentration of the agent required to significantly inhibit microbial growth. Inhibition is considered “significant” if an 80% or greater reduction in the growth of an inoculum of Staphylococcus epidermidis is observed, relative to a control medium without an anti-microbial agent, over a period of 16 to 24 hours at 37°C. Details of suitable methods for determining MICs can be found in “Antimicrobial Agents and Susceptibility Testing”, C.Thornsberry, (in “Manual of Clinical Microbiology”, 5^th Edition, Ed. A. Balows et al, American Society for Microbiology, Washington D.C., 1991). A particularly suitable method is the Macrobroth Dilution Method as described in Chapter 110 of above publication (pp.

1101-1111) by D. F. Sahm and J. A. Washington II. MICs of anti-microbials suitable for inclusion in the compositions of the invention are triclosan: 0.01-10 pg. ml'¹ (J. Regos et al., Dermatologica (1979), 158: 72-79) and farnesol: ca. 25 pg. ml'¹ (K. Sawano, T.

Sato, and R. Hattori, Proceedings of the 17^th IFSCC International Conference, Yokahama (1992) p.210-232). By contrast ethanol and similar alkanols have MICs of greater than 1 mg. ml'¹.

Suitable organic anti-microbials are bactericides, for example quaternary ammonium compounds, like cetyltrimethylammonium salts; chlorhexidine and salts thereof; and diglycerol monocaprate, diglycerol monolaurate, glycerol monolaurate, and similar materials, as described in “Deodorant Ingredients”, S. A. Makin and M.R. Lowry, in “Antiperspirants and Deodorants”, Ed. K. Laden (1999, Marcel Dekker, New York). More preferred anti-microbials for use in the compositions of the invention are polyhexamethylene biguanide salts (also known as polyaminopropyl biguanide salts), an example being Cosmocil CQ™ available from Zeneca PLC, preferably used at up to 1 % and more preferably at 0.03% to 0.3% by weight; 2',4,4'-trichloro,2-hydroxy- diphenyl ether (triclosan), preferably used at up to 1 % by weight of the composition and more preferably at 0.05-0.3%; and 3,7,11-trimethyldodeca-2, 6,10-trienol (farnesol), preferably used at up to 1% by weight of the composition and more preferably at up to 0.5%. Other suitable organic antimicrobial agents are transition metal chelators, as described in W001/52805, for example. Transitional metal chelators having a binding coefficient for iron(lll) of greater than 10²⁶, for example diethylenetriaminepentaacetic acid and salts thereof are preferred.

Method and Use

The present invention also provides for a method of preventing sweat from rapidly being released, absorbing or managing excess sweat comprising a step of topical application of the composition of the first aspect. Preferably, the present invention provides for a method wherein the composition of the first aspect is applied on the underarms. The present invention also provides for a method wherein topical application of the composition of the first aspect preventing sweat from rapidly being released, absorbing or managing excess sweat on the desired skin surface of the human body. The method in accordance with the invention is preferably non- therapeutic. By non-therapeutic is meant that the method is cosmetic in nature. “Preventing sweat from rapidly being released” herein means reducing the rate of release of sweat.

The invention also provides for use of the composition of the first aspect for preventing sweat from rapidly being released, absorbing or managing excess sweat on the desired skin surface. Preferably, the desired skin surface is the skin of underarms. The use in accordance with the invention is preferably non-therapeutic in nature, more preferably cosmetic in nature. “Preventing sweat from rapidly being released” herein means reducing the rate of release of sweat.

The invention will now be demonstrated with the help of the following non-limiting examples.

Examples

This example demonstrated the composition as per the invention are capable of forming an aggregation/precipitation under the test conditions. The compositions according to the formulations detailed in Table 1 are prepared. All ingredients are expressed by weight percent of the total formulation, and as level of active ingredient.

TABLE 1

The composition of model ionic sweat (pH 6.9) according to the formulation detailed in

Table 2 are prepared:

TABLE 2

Experiment methods:

An experiment was arranged using the device as disclosed in the International Application WO2018099931 A1 (Unilever).

The device has a 20X20 pm channel. Before use, the channel was filled with model ionic sweat. The surface tension of the model ionic sweat is strong and prevents its flowing in the capillary. The concerned composition in Table 2 was placed at one end of the channel. When the composition contacts with the model ionic sweat, the composition of the present invention is believed to turn into something like an aggregation/agglomeration. This phenomenon simulates the manner in which an active agent forms aggregation/agglomeration thereby provides benefit of preventing sweat from rapidly being released, absorbing or managing excess sweat.

The whole process was monitored under optical microscope (Leica™ DM 2500P).

The efficacy was investigated by measuring the least hydraulic pressure needed for the water to pass through the capillary with flow rate not lower than O.lpL/min. The least hydraulic pressure is believed to be affected (improved) by the presence of the aggregation or the precipitate. If the least hydraulic pressure is high, it indicates the good formation of an aggregation or a precipitate with at the end of the channel. The water was pumped into the channel from the other end of the channel by using pressure pump with flow-rate monitor and hydraulic pressure control (MFCStm-EZ, FLUIGENT).

The data on the aggregation/agglomeration formation of the compositions at the end of the channel after 60 minutes is summarized in Table 3 below:

TABLE 3

The results (shown in the Table 3) demonstrate that compositions as per the invention (Samples 1) is more capable of forming an aggregation/precipitation under the test conditions disclosed earlier, which further indicates their ability to effectively prevent sweat from rapidly being released, absorb or manage excess sweat when used in a cosmetic composition, comparing with the composition outside the invention (Sample A and B).

Claims

1. A cosmetic composition comprising:

(i) ethanol;

(ii) a cationic surfactant which is ethyl lauroyl arginate HCI;

(iii) amphiphilic material being a substance or mixture of substances which forms, upon contact with sweat, a water-insoluble liquid crystal phase of greater than one dimensional periodicity; wherein the weight ratio of amphiphilic material to said cationic surfactant is from 60:1 to 1:2.

2. A composition as claimed in claim 1 wherein the amphiphilic material forms cubic or hexagonal phase on contact with sweat.

3. A composition as claimed in claim 1 or 2 wherein the amphiphilic material is a mixture of amphiphilic materials selected from:

(i) oleyl alcohol and glyceryl monolaurate at a weight ratio of from 28: 72 to 44: 56;

(ii) oleyl alcohol and triethylene glycol mono hexadecyl ether at a weight ratio of from 15: 85 to 25: 75;

(iii) glyceryl monooleate and silicone oil (DC 246 ex Dow Corning) at a weight ratio of from 87: 13 to 80: 20;

(iv) oleyl alcohol and alkyl polyglucoside (APG 600 ex Henkel) at a weight ratio of from 50: 50 to 60: 40 and

(v) isostearyl alcohol and glyceryl monolaurate at a weight ratio of from 25: 75 to 45: 55.

4. A composition as claimed in claim 1 or 2 wherein the amphiphilic material comprises a lipid substance selected from glycerol monooleate and glycerol monolaurate.

5. A composition as claimed in claim 4, wherein the amphiphilic material also comprises a material selected from the group consisting of: oleic acid, oleyl alcohol, isostearyl alcohol, stearyl alcohol and 1 -mono-isostearyl glyceryl ether.

6. A composition as claimed in claim5 wherein the amphiphilic material comprises a mixture of glycerol monolaurate and isostearyl alcohol.

7. A composition as claimed in claim 6, wherein the amphiphilic material is a mixture of isostearyl alcohol and glyceryl monolaurate at a weight ratio of from 25: 75 to 45: 55.

8. A composition as claimed in any of claims 1 to 7 wherein the composition comprises a volatile silicone, preferably said volatile silicone comprises greater than 90% by weight of siloxanes selected from the group consisting of hexamethyldisiloxane, octamethyltrisiiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane and decamethylcyclopentasiloxane.

9. A composition as claimed in any of claims 1 to 8 wherein said composition comprises an antimicrobial deodorant active.

10. A composition as claimed in any of claims 1 to 9 wherein said composition is in the form of a spray, firm solid, soft solid, cream, or is an emulsion packaged in a roll-on applicator.

11. A composition as claimed in any of claims 1 to 10 when said composition is a spray it comprises a propellant and is in the form of an aerosol.

12. A method of preventing sweat from rapidly being released, absorbing or managing excess sweat comprising a step of topical application of the composition as claimed in any of claims 1 to 11 on to the desired skin surface.

13. Use of a composition as claimed in any of claims 1 to 11 for preventing sweat from rapidly being released, absorbing or managing excess sweat on the desired skin surface.