WO2000056277A1

WO2000056277A1 - Cosmetic towelettes

Info

Publication number: WO2000056277A1
Application number: PCT/EP2000/002022
Authority: WO
Inventors: Craig Stephen Slavtcheff; Alexander Paul Znaiden; Vispi Dorab Kanga
Original assignee: Unilever Plc; Unilever Nv; Hindustan Lever Limited
Priority date: 1999-03-18
Filing date: 2000-03-08
Publication date: 2000-09-28
Also published as: AU3809300A

Abstract

A disposable towelette is provided which includes a flexible substrate such as a cellulosic tissue impregnated with an astringent salt of a metal selected from aluminum, zinc, zirconium or mixtures thereof delivered in a cosmetically acceptable carrier vehicle. There is further provided a method for removing sebum and reducing perceived oil and greasiness by wiping the skin with the impregnated towelette.

Description

COSMETIC TOWELETTES

BACKGROUND OF THE INVENTION

Field of the Invention

The invention concerns single use towelettes for cosmetically removing sebum from facial surfaces.

The Related Art

Sebum is produced by the disruption of the cells in which it is formed (in the basal layer of the gland) . This function may be termed holocrine secretion. Being liquid inside the duct and hair follicle, sebum diffuses up and down the follicular canal . Upon reaching the skin surface it combines with epithelial lipids (from the keratinizing cells) and emulsifies as an oily liquid with water from the sweat glands. In this way a semi-solid, slightly acid, hydrophilic film is formed on the skin and in the hair follicles. The quantity of sebum produced is directly proportional to the size of the gland.

The rate of sebum production varies in different individuals, some having oilier skins than others. Male sex hormones increase sebum production. Increased temperature also increases production. The literature is replete with methods and compositions for eliminating, controlling or at least reducing the levels of skin oils and greasiness. None have proved totally satisfactory.

U.S. Patent 5,403,588 (Santa Ana, Jr.) discloses a body deodorizing composition consisting essentially of aluminum chloride in a carrier mixture of 70% isopropyl alcohol and acetone solution. The composition is impregnated into absorbent cotton pads which are packaged in individual pouches. Rubbing the saturated cotton pad on the skin, preferably in the underarm area, provides a cleansing and removes substances which contribute to body odor.

JP 08 188517 and JP 59 164712 both to Kanebo report that

Baker's yeast extract and levulinic acid, respectively are sebum secretion inhibitors. Astringent agents are suggested as further additives for formulations containing these inhibitors. Illustrative are substances such as citric, tartaric, lactic, malic acids as well as zinc phenol sulphonate and aluminum chloride or chlorohydroxide .

Open questions with respect to the inhibitors is their effectiveness under conditions of high environmental humidity and temperature. Even with control of sebum, consumers many times perceive normal oiliness as being abnormal because of optical effects, sensorial signals and interaction with make-up and perspiration. Thus the problem is not merely the presentation of a sebum inhibitor but providing a system controlling both the underlying problem and the surface perception of that problem. Accordingly, it is an object of the present invention to provide an improved method for managing skin oiliness and greasiness as well as solving related optical effects, sensorial sensation and interaction with make-up and perspiration.

Another object of the present invention is to provide a system that modulates the manner in which skin sebum is distributed on skin which impacts the perception of oiliness even under conditions of high environmental humidity and temperature .

These and other objects of the present invention will become more apparent from the following summary and detailed discussion which follow.

SUMMARY OF THE INVENTION

A disposable, towelette is provided for removing sebum from skin, the towelette including:

(i) a substrate; (ii) an astringent salt; and

(iii) a cosmetically acceptable vehicle for impregnating the astringent salt as a composition onto the substrate .

A method is also provided for removing sebum and for reducing perceived oiliness on skin, the method including: (a) providing a towelette which is constituted of:

(i) a substrate; (ii) an astringent salt; and (iii) a cosmetically acceptable vehicle for impregnating the astringent salt as a composition onto the substrate; and

(b) wiping a surface of the skin with the towelette,

DETAILED DESCRIPTION OF THE INVENTION

Now it has been found that towelettes impregnated with astringent salts can efficiently remove sebum, oil and grease from the skin. Most especially it has been found that a consumer's perception of oiliness which may be related to other extrinsic factors such as optical effects, sensorial signals and interaction of sebum with make-up and perspiration can be minimized by applying the astringent salts in a carrier on a substrate tissue. The product is preferably a single use towelette which provides a convenient, aesthetically pleasing, non-whitening surface treatment for the skin. The term skin is meant to encompass all external areas of the body including scalp and hair. The uniformly impregnated towelettes distribute the astringent salt composition on the skin in a much more even manner than fluid, gel or stick products. The perception of oiliness removal is thereby much improved.

A first necessary aspect of the present invention is that of a substrate. Preferably the substrate is a water insoluble substance. By "water insoluble" is meant that the substrate does not dissolve in or readily break apart upon immersion in water. Without being limited by theory, it is believed that the substrate serves to more evenly distribute the sebum controlling astringent salts across a wide area of the skin being so treated. Simultaneously the substrate serves to absorb excess oil and grease. Likewise, the substrate removes the make-up and perspiration which would ordinarily enhance a consumer's perception of oily skin. In these ways the substrate and astringent salts interact with one another to provide the many benefits of this invention. Another advantage of the substrate in combination with the astringent salts is that former help the astringent salts penetrate the sebaceous glands. The substrate is also much better than a mere liquid or gel formulation in the accurate application to the skin and avoidance of sensitive areas such as inadvertently directing the astringent composition to areas of the eye thereby irritating same.

A wide variety of materials can be used as the substrate.

The following nonlimiting characteristics are desirable: (I) sufficient wet strength for use, (ii) sufficient abrasivity, (iii) sufficient loft and porosity, (iv) sufficient thickness, (v) appropriate size, and (vi) non-reactive with the astringent salt composition.

Nonlimiting examples of suitable substrates which meet the above criteria include nonwoven substrates, woven substrates, hydroentangled substrates, air entangled substrates and the like. Preferred embodiments employ nonwoven substrates since they are economical and readily available in a variety of materials. By nonwoven is meant that the layer is comprised of fibers which are not woven into a fabric but rather are formed into a sheet, particularly a tissue. The fibers can either be random (i.e., randomly aligned) or they can be carded (i.e. combed to be oriented in primarily one direction) . Furthermore, the nonwoven substrate can be composed of a combination of layers of random and carded fibers.

Nonwoven substrates may be comprised of a variety of materials both natural and synthetic. By natural is meant that the materials are derived from plants, animals, insects or byproducts. By synthetic is meant that the materials are obtained primarily from various man-made materials or from material that is usually a fibrous web comprising any of the common synthetic or natural textile- length fibers, or mixtures thereof .

Nonlimiting examples of natural materials useful in the present invention are silk fibers, keratin fibers and cellulosic fibers. Nonlimiting examples of keratin fibers include those selected from the group consisting of wool fibers, camel hair fibers, and the like. Nonlimiting examples of cellulosic fibers include those selected from the group consisting of wood pulp fibers, cotton fibers, hemp fibers, jute fibers, flax fibers, and mixtures thereof. Wood pulp fibers are preferred while all cotton fibers (e.g. cotton pads) are normally avoided. Nonlimiting examples of synthetic materials useful in the present invention include those selected from the group consisting of acetate fibers, acrylic fibers, cellulose ester fibers, modacrylic fibers, polyamide fibers, polyester fibers, polyolefin fibers, polyvinyl alcohol fibers, rayon fibers and mixtures thereof . Examples of some of these

® synthetic materials include acrylics such as Acrilan ,

® ®

Creslan , and the acrylonitrile-based fiber, Orion ;

® cellulose ester fibers such as cellulose acetate, Arnel ,

® and Acele ; polyamides such as Nylons (e.g., Nylon 6, Nylon

® 66, Nylon 610 and the like); polyesters such as Fortrel ,

® ®

Kodel , and the polyethylene terephthalate fibers, Dacron ; polyolefins such as polypropylene, polyethylene; polyvinyl acetate fibers and mixtures thereof.

Nonwoven substrates made from natural materials consist of webs or sheets most commonly formed on a fine wire screen from a liquid suspension of the fibers.

Substrates made from natural materials useful in the present invention can be obtained from a wide variety of commercial sources. Nonlimiting examples of suitable commercially

® available paper layers useful herein include Airtex , an embossed airlaid cellulosic layer having a base weight of about 71 gsy, available from James River Corporation, Green

® Bay, WI ; and Walkisoft , an embossed airlaid cellulosic having a base weight of about 75 gsy, available from Walkisoft U.S.A., Mount Holly, NC . Nonwoven substrates made from synthetic materials useful in the present invention can also be obtained from a wide variety of commercial sources. Nonlimiting examples of suitable nonwoven layer materials useful herein include HEF 40-047, an apertured hydroentangled material containing about 50% rayon and 50% polyester, and having a basis weight of about 43 grams per square yard (gsy) , available from Veratec, Inc., Walpole, MA; HEF 140-102, an apertured hydroentangled material containing about 50% rayon and 50% polyester, and having a basis weight of about 56 gsy,

® available from Veratec, Inc., Walpole, MA; Novenet 149-191, a thermo-bonded grid patterned material containing about 69% rayon, about 25% polypropylene, and about 6% cotton, and having a basis weight of about 100 gsy, available from

® Veratec, Inc., Walpole, MA; HEF Nubtex 149-801, a nubbed, apertured hydroentangled material, containing about 100% polyester, and having a basis weight of about 70 gsy,

® available from Veratec, Inc. Walpole, MA; Keybak 951V, a dry formed apertured material, containing about 75% rayon, about 25% acrylic fibers, and having a basis weight of about

43 gsy, available from Chicopee Corporation, New Brunswick,

® NJ; Keybak 1368, an apertured material, containing about

75% rayon, about 5% polyester, and having a basis weight of about 39 gsy, available from Chicopee Corporation, New

® Brunswick, NJ; Duralace 1236, an apertured, hydroentangled material, containing about 100% rayon, and having a basis weight from about 40 gsy to about 115 gsy, available from

® Chicopee Corporation, New Brunswick, NJ; Duralace 5904, an apertured, hydroentangled material, containing about 100% polyester, and having a basis weight from about 40 gsy to about 115 gsy, available from Chicopee Corporation, New

® Brunswick, NJ; Sontaro 8868, a hydroentangled material, containing about 50% cellulose and about 50% polyester, and having a basis weight of about 60 gsy, available from Dupont Chemical Corp.

Most preferred as a towelette for purposes of this invention are non-woven substrates, especially blends of rayon/polyester and ratios of 10:90 to 90:10, preferably ratios of 20:80 to 80:20, optimally 40:60 to 60:40 by weight. A most useful towelette is a 70:30 rayon/polyester non-woven wipe article.

The substrate can be made into a wide variety of shapes and forms. Generally the substrate is in single use towelette form. Advantageously, the towelettes are folded in a Z- shaped formation. They may be interleaved with one another but preferably are not interleaved. The Z fold consists of a center panel flanked by upper and lower wing panels. The upper and lower wing panels are substantially of equal width and substantially half of a width of the center panel. Each towelette is folded medially in a direction orthogonal to that of the Z-shaped formation. Advantageously the size of the towelette may range in length from 10 to 40 cm, preferably from 15 to 30 cm, optimally from 18 to 24 cm. The width of the towelette may range from 8 to 30 cm, preferably from 10 to 25 cm, optimally from 15 to 20 cm. Anywhere from 5 to 100, preferably from 10 to 50 single towelettes may be stored within a dispensing pouch, preferably a moisture impermeable pouch. During storage and between dispensing, the pouch is resealable, usually via an adhesive strip covering a dispensing opening. Single towelette containing pouches may also be employed. The substrates of the present invention can comprise two or more layers, each having a different texture and abrasiveness . The differing textures can result from the use of different combinations of materials or from the use of a substrate having a more abrasive side for exfoliation and a softer, absorbent side for gentle cleansing. In addition, separate layers of the substrate can be manufactured to have different colors, thereby helping the user to further distinguish the surfaces.

A second important element of the present invention is that of an astringent salt. These salts include organic and inorganic salts of aluminum, zirconium, zinc and mixtures thereof. The anion of the astringent salt may be a sulphate, sulphonate, chloride, chlorohydroxide, alum, formate, lactate, benzenesulphonate or phenolsulphonate . Suitable classes of the astringent salts include aluminum halides, aluminum hydroxyhalides, zirconyl oxyhalides, zirconyl hydroxyhalides, zinc chloride, zinc phenolsulphonate and mixtures thereof.

Exemplary aluminum salts include the aluminum hydroxyhalides having the general formula Al₂ (OH) _xQ_yXH₂θ, where Q is chlorine, bromine or iodine; x is about 2 to about 5; x=y is about 6, wherein x and y are not necessarily integers; and X is about 1 to about 6. Exemplary zirconium compounds include zirconium oxy salts and zirconium hydroxy salts, also referred to as zirconyl salts and zirconyl hydroxy salts, and represented by the general empirical formula

ZrO (OH) ₂-nzLz/ where z varies from about 0.9 to about 2 and is not necessarily an integer; n is the valence of L; 2-nz is greater than or equal to 0; and L is selected from the group consisting of halides, nitrate, sulfonate, sulfate, and mixtures thereof .

Specific examples of astringent salts include, but are not limited to, aluminum bromohydrate, potassium alum, sodium aluminum chlorohydroxy lactate, aluminum sulfate, aluminum chlorohydrate, aluminum- zirconium polychlorohydrate complexed with glycine, aluminum- zirconium trichlorohydrate, aluminum- zirconium octachlorohydrate, aluminum sesquichlorohydrate, aluminum sesquichlorohydrex PG, aluminum chlorohydrex PEG, aluminum zirconium octachlorohydrex glycine complex, aluminum zirconium pentachlorohydrex glycine complex, aluminum zirconium tetrachlorohydrex glycine complex, aluminum zirconium trichlorohydrex glycine complex, aluminum chlorohydrex PG, zirconium chlorohydrate, aluminum dichlorohydrate, aluminum dichlorohydrex PEG, aluminum dichlorohydrex PG, aluminum sesquichlorohydrex PG, aluminum chloride, aluminum zirconium pentachlorohydrate, and mixtures thereof.

Astringent salts of the present invention may range in amounts from about 1 to about 50%, preferably from about 8 to about 35%, optimally from about 12 to about 18% by weight of the total composition which impregnates the substrate. Other materials benefiting control of oily skin such as water insoluble particulates may also be incorporated into compositions of this invention. They include: silica, zeolite, diatomaceous earth, polyethylene, microporous particles and combinations thereof. These further materials may be present in amounts from about 0.1 to about 30%, preferably from about 0.5 to about 10% by weight of the composition.

The amount of impregnating composition relative to the substrate may range from about 20:1 to 1:20, preferably from 10:1 to about 1:10 and optimally from about 2:1 to about 1:2 by weight .

Astringent salts are normally very drying and leave the skin with a taut unpleasant feeling. These salts also tend to leave a white aesthetically displeasing layer on the skin surface. Problems of drying and whitening can be overcome by including a polyol within the impregnating compositions of this invention. Representative polyols include glycerine, diglycerine, polyalkylene glycols and more preferably alkylene polyols and their derivatives including propylene glycol, dipropylene glycol , polypropylene glycol , polyethylene glycol and derivatives thereof, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1,2-butylene glycol, 1, 2 , 6-hexanetriol , isoprene glycol, ethoxylated glycerol , propoxylated glycerol and mixtures thereof. The most preferred is 2 -methyl -1 , 3-propanediol available as MP Diol from the Arco Chemical Company. Amounts of the polyol may range from about 0.5 to about 95%, preferably from about 1 to about 50%, more preferably from about 1.5 to 20%, optimally from about 3 to about 10% by weight of the impregnating composition.

A variety of cosmetically acceptable carriers may be employed although the carrier normally will be a fluid, particularly water. Less preferred but suitable are solid carriers such as dry encapsulates (e.g. polysaccharides, polyurethanes, polyacrylates, polyvinylacetates) enrobing the astringent salts. Illustrative are microporous beads available from Advanced Polymer Systems Inc. under the

® trademark Microsponge and a variety of other cross-linked polyacrylate superabsorbent beads.

Amounts of the carrier vehicle may range from about 0.5 to about 99%, preferably from about 1 to about 80%, more preferably from about 50 to about 70%, optimally from about 65 to 75% by weight of the impregnating composition.

Preservatives can desirably be incorporated into the cosmetic compositions of this invention to protect against the growth of potentially harmful microorganisms . Suitable traditional preservatives for compositions of this invention are alkyl esters of para-hydroxybenzoic acid. Other preservatives which have more recently come into use include hydantoin derivatives, propionate salts, and a variety of quaternary ammonium compounds. Cosmetic chemists are familiar with appropriate preservatives and routinely choose them to satisfy the preservative challenge test and to provide product stability. Particularly preferred preservatives are phenoxyethanol , methyl paraben, propyl paraben, imidazolidinyl urea, sodium dehydroacetate and benzyl alcohol. The preservatives should be selected having regard for the use of the composition and possible incompatibilities between the preservatives and other ingredients in the composition. Preservatives are preferably employed in amounts ranging from 0.01% to 2% by weight of the composition.

Compositions of the present invention may further include herbal extracts. Illustrative extracts include Roman Chamomile, Green Tea, Scullcap, Nettle Root, Swertia Japonica, Fennel and Aloe Vera extracts. Amount of each of the extracts may range from about 0.001 to about 1%, preferably from about 0.01 to about 0.5%, optimally from about 0.05 to about 0.2% by weight of a composition.

Minor adjunct ingredients may also be present in the compositions. Among these may be vitamins such as Vitamin E Acetate, Vitamin C, Vitamin A Palmitate, Panthenol and any of the Vitamin B complexes. Anti-irritant agents may also be present including those of alpha-bisabolol and potassium glycyhrizzinate, each vitamin or anti-irritant agent being present in amounts ranging from about 0.001 to about 0.5%, preferably from about 0.01 to about 0.1% by weight of the composition.

Other adjunct ingredients include such oil control agents as beta-hydroxy acids (particularly salicylic acid) , antimicrobials (particularly triclosan) , vasoactive compounds (particularly sennosides) and combinations thereof in amounts ranging from about 0.1 to about 10% by weight of the composition.

Emulsifiers may also be incorporated into compositions of this invention. These emulsifiers may be anionic, nonionic, cationic, amphoteric and combinations thereof. Useful nonionic type emulsifiers include the C₁₀-C₂₀ fatty alcohol or acid hydrophobes condensed with from 2 to 100 moles of ethylene oxide or propylene oxide per mole of hydrophobe; C₂-C₁₀ alkyl phenols condensed with from 2 to 20 moles of alkylene oxide; mono- and di- fatty acid esters of ethylene glycol; fatty acid monoglyceride; sorbitan, mono- and di-Cβ-

C₂₀ fatty acids; block copolymers (ethylene oxide/propylene oxide) ; and polyoxyethylene sorbitan as well as combinations thereof. Alkyl polyglycosides and saccharide fatty amides (e.g. methyl gluconamides) are also suitable nonionic emulsifiers. Particularly preferred as the emulsifier is a hydrogenated castor wax alkoxylated with 40 moles ethylene

® oxide, available commercially as Cremophore RH-40 .

Mild emulsifiers of the anionic and amphoteric type may also be employed. Particularly preferred anionic examples include lauroamphoacetate salts and sarcosinate salts. Preferred amphoterics include cocamidopropylbetaine and dimethylbetaine .

Amounts of the emulsifiers may range from about 0.05 to about 20%, preferably from about 0.1 to about 5%, optimally from about 0.5 to about 0.8% by weight. Compositions of this invention will generally not contain levulinic acid, salts thereof, Baker's yeast or even acetone at levels to influence activity performance. These formulations may involve a range of pH although it is preferred to have a relatively low pH, for instance, a pH from about 2 to about 6.5, preferably from about 2.5 to about 4.5.

The following examples will more fully illustrate the embodiments of this invention. All parts, percentages and proportions referred to herein and in the appended claims are by weight unless otherwise illustrated.

EXAMPLES 1-8

Table I provides a listing of formulations which were prepared for impregnation into a cellulosic substrate forming a towelette. The pH of the resulting composition solutions range from about 2.8 to about 3.

TABLE I

EXAMPLE 9

A clinical study was performed to evaluate the effectiveness of towelettes according to the present invention. Six panelists were chosen. Sebum on the facial areas of the panelists were measured by a sebumeter device. The protocol involved baseline readings on left and right cheek areas before and after washing. Two sites on the left cheek of each panelist were left untreated as control areas. Two sites on the right cheek of each panelist were treated with a rayon/polyester towelette impregnated with a 15% aluminum zirconium chlorohydrate glycinate salt solution. See formulation under Example 3. The impregnated towelette was wiped over the right cheek test sites five minutes after initial baseline readings.

Sebumeter values were taken at two hours, four hours and six hours subsequent to treatment. Sebum reduction relative to the untreated control cheek averaged respectively 8%, 45% and 16% over the time period for an average of the six member panel.

The foregoing description and examples illustrate selected embodiments of the present invention.

Claims

1. A disposable towelette for removing sebum from skin, the towelette comprising:

(i) a substrate; (ii) an astringent salt; and (iii) a cosmetically acceptable vehicle for impregnating the astringent salt as a composition onto the substrate.

2. The towelette according to claim 1 wherein the astringent is selected from the group consisting of aluminum chlorohydrate, aluminum zirconyl chlorohydrate glycinate, aluminum chloride and combinations thereof.

3. The towelette according to claim 1 or 2 wherein the astringent salt is zinc chloride, zinc phenol sulphonate and mixtures thereof .

4. The towelette according to any preceding claim wherein the vehicle is water.

5. The towelette according to any preceding claim wherein the composition further comprises from 0.5 to 95% of a polyol by weight of the impregnating composition.

6. The towelette according to claim 5 wherein the polyol is selected from the group consisting of glycerine, diglycerine, hexylene glycol, 2 -methyl -1 , 3-propanediol , PPG-10 butanediol and mixtures thereof.

7. The towelette according to claim 5 or 6 wherein the amount of polyol present ranges from 1.5 to 20% by weight of the impregnating composition.

8. The towelette according to any preceding claim wherein the substrate is a blend of rayon/polyester in a weight ratio ranging from 10:90 to 90:10.

9. The towelette according to any preceding claim wherein the substrate is a tissue folded in a Z-shaped formation.

10. A cosmetic method for removing sebum and reducing perceived oiliness on skin, the method comprising:

(a) providing a towelette comprising:

(i) a substrate; (ii) an astringent salt; and

(iii) a cosmetically acceptable vehicle for impregnating the astringent salt as a composition onto the substrate; and

(b) wiping a surface of the skin with the towelette.