Title of Invention

COSMETIC STICK PRODUCT COMPRISING A COSMETIC STICK COMPOSITION AND A COATING

Abstract A cosmetic stick product comprising a cosmetic stick composition and a coating for said composition that has a melting point of greater than 30°C, adheres to the external surface of the cosmetic stick composition, and is capable of being abraded during use.
Full Text FORM -2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See Section 10)
COSMETIC STICK PRODUCT COMPRISING A COMETIC STICK
COMPOSITION AND A CATING.
HNDUSTAN LEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at Hindustan Lever House, 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.




ORIGINAL
954/MUM/2002
01/11/02

GRANTED
9-11-2004

Technical field
The invention relates to an improved solid compositions for topical application, and in particular to cosmetic products comprising a solid or soft solid composition in the form of a stick, surrounded and contained by a protective coating.
Background and prior art
Perspiration, often called sweat, is basically a clear liquid excreted by the eccrine and apocrine glands. The sweat can be retained on occluded regions of skin, such as in the underarm, where it is degraded by skin bacteria, resulting in the bad odour often associated with perspiration/sweat. Apart from cleansing, one way to control such body odours is by the application of cosmetic compositions, in particular, the application of antiperspirant and/or deodorant compositions products to the underarm areas of the body.
Cosmetic compositions, for example antiperspirants, deodorants, or other fragrance-containing compositions, are applied topically to human skin in a variety of physical forms, including sprays, including pumped and aerosol sprays, liquids, soft solids (including gels and creams) and solid sticks. Traditionally, solids and soft solids have been applied using substantial packaging, serving the purpose of containing the product and raising it through the packaging in readiness for application to the skin. such devices are described in US 4,950,094 (Yorks, 1990), amongst other publications.

In recent times, there has been a desire to reduce the amount of packaging employed in consumer products; both for environmental reasons and for cost saving. In the field of cosmetic sticks, reusable packaging has been considered as an option for achieving this aim; see, for example, WO 92/08388 (Lepsius et al, 1992) and WO 93/25113 (Dornbusch et al, 1993). However, such an approach has the problems of still involving a substantial dispenser and requires the consumer to suffer the inconvenience of having to re-fill the same.

Solid and soft solid deodorant/antiperspirant stick compositions generally comprise a safe and effective level of an anti-microbial agent incorporated into a base comprising a solidifying agent, a liquid carrier, and optional sensory modifiers, for example silicones or hydrocarbon or ester or ether emollients, to deliver the desired skin feel. Often, one or more of the components may be volatile, for example, a volatile silicone, further necessitating some form of packaging, in order to reduce evaporative loss of the volatile component(s) and the resulting adverse effect upon the physical and sensory properties of the stick.
In WO 02/090475, a coating for a shaped detergent product is described, said coating being water-resistant and capable of being abraded during use. Preferably, the coating comprises one or more materials having a water vapour
permeability coefficient less than:
[Cm3\[cm] 5000X10-13. [cm2]Pa]
and a melting point greater than 30°C, wherein [Cm3] = Cm3(273,15K; 1,013 x 105 Pa.)> as outlined in "Polymer Handbook, 1989, Third edition, Eds. J.Brandrup and E.H. Immergut, (Wiley-lnterscience Publication), page VI/436". Such materials may be photo curabla or non-photo curable.
The use of coatings as described in WO 02/090475 for cosmetic stick compositions has not previously been considered. Such an approach has several advantages. In particular, it can alleviate the problems referred to above, especially reducing the packaging requirement and yet still preventing or reducing the loss of volatile component(s) from the stick. The coating improves the mechani of the stick and the perfume retention is also superior to a stick without any coating or other packaging. In addition, the coating may conveniently abrade during use. However, it has also been found in the course of the investigations resulting in the instant invention that alternative coating materials can be employed in addition to or instead of such polymers.


objectives of the present invention are to provide packaging for a cosmetic stick composition in the form of a selected coating or film, which preferably can offer one or more of the following advantages, namely be readily applied, and/or which can provide the required containment of the composition, and/or which can prevent or restrict the loss of volatile components, including perfumes, if present, from the formulation.
Further objectives of one or more preferred embodiments the invention are to provide a selected coating for a cosmetic stick composition which satisfies one or more or the following criteria, namely has good adhesion to the surface of the composition, which has defined thickness, and/or which has good mechanical properties, but gets abraded during use.
Furthermore, it is an objective of a further aspect of the present invention to provide a process for obtaining the coated cosmetic stick composition, the coating preferably having one or more of the advantages referred to above.
Description of the invention
According to a first aspect of the present invention, there is provided a cosmetic stick product comprising a cosmetic stick composition and a coating for said composition that has a melting point of greater than 30°C, adheres to the external surface of the cosmetic stick composition, is capable of being abraded during use and preferably is non-irritating to the human skin.
According to a second aspect of the present invention, there is provided a method of preparing a coated cosmetic stick product comprising the steps of forming a cosmetic stick composition , liquifying a coating composition comprising an organic coating material having a melting point of at least 30°C, applying the liquified coating composition to the stick composition in an amount sufficient to form a coating thereon. In one way of carrying out the second aspect, the coating composition comprises aphoto-curable component and a photo-initiator to a

cosmetic stick, followed by irradiation with light of an appropriate wavelength for initiating curing of the liquid coating composition, resulting in the formation of a solid coating around the cosmetic stick composition. In a second way of carrying out the method, the coating material comprises a wax. The coating composition forms an integral self-supporting mass at the time of application of the coating composition.
The instant invention is to be contrasted with the concept of introducing the stick composition into a pouch or sleeve, even one made from a thermoplastic polymer. Such a pouch or sleeve is intended to act as a wrapping and retain its integrity during application if the stick, i.e. not be abraded during use.
By the application of coating of an organic material, which coating has a melting point of at least 30°C, it is possible to provide the core cosmetic composition therein with a protective outer skin which is able to be abraded in use and which can be non-irritating to human skin.
In the following description, all percentages should be understood to be percentages by weight of the total relevant composition unless indicated specifically to the contrary.
The cosmetic stick composition
The cosmetic stick composition is, for example, an antiperspirant stick composition, a deodorant stick composition, or other fragrance-containing stick composition, and especially one intended for use to combat body malodour. Antiperspirant stick compositions are particularly suitable for use in the present invention. The cosmetic composition may take the form of a solid or soft solid composition (including gels and creams), although the invention is of particular benefit for solid stick compositions, in particular those having a hardness of greater than 0.5 N/mm2, as measured by sphere indentation as described in WO 01/51020. Soft solids typically have a hardness of from 0.005 to 0.1 n/mm2, when measured using the same technique.
Preferred cosmetic stick compositions comprise: A) an antiperspirant active, a deodorant active, or a fragrance; B) a carrier fluid; C) a structurant for the carrier fluid, (sometimes otherwise called a gellant).
It is particularly preferred that component A is an antiperspirant active or a deodorant active. It is preferred that B is present at a level of from 5 to 95%, particularly 20 to 60%, and that C is present at a level of from 0.1 to 50%, particularly 1 to 25%.
The cosmetic stick composition may be gel type or wax type depending upon the particular liquid base material and solidifying agent used. These compositions may also comprise effective amounts of antiperspirant or deodorant active.
The cosmetic stick composition may be a homogeneous mixture, such as a solution, or it may be a heterogeneous mixture, such as an emulsion of a disperse liquid in a continuous phase or a suspension of a particulate material in a continuous phase.
The cosmetic stick composition may be manufactured by extrusion, casting or injection moulding or any other technique known in the art. At the time at which the coating composition is applied, it is normally in the form of a stick, that is to say a unitary mass having a base, a side and a top which top is brought into contact with skin to apply the cosmetic active. Sticks may be of any shape at the discretion of the manufacturer, usually having a weight of from 10 to 100g. Conventionally they are dimensioned to be held by a human hand, typically adopting the form of a rod having a height of from 20 to 80mm and a cross section which can range from circular, via oval to a rectangle with rounded ends having a cross section of 300 to 2000 mm2. In a number of preferred embodiments of the instant invention, the core stick weighs from abou15...to 35g.and. has a height of from about 30 to 50mm. The combination of a small stick and an abradable
protective outer coating provides consumers of restricted income with a more affordable cosmetic product that still contains a high quality cosmetic active. Anti-perspirant actives are often selected from astringent active salts, including in particular aluminium, zirconium and mixed aluminium/zirconium salts, including both inorganic salts and organic salts and complexes. Preferred astringent salts include aluminium, zirconium and aluminium/zirconium halides and halohydrate salts, such as chlorohydrates. some especially preferred halohydrate salts comprise activated aluminium chlorohydrates such as those described in EP-A-6739 (Unilever NV et a/) and other actives are described in EP-A-28853.
Astringent aluminium salts include aluminium chloride and aluminium halohydrates having the general formula AI2(OH)xQy.zH20 in which Q represents chlorine, bromine or iodine, x is from 2 to 5 and x+y = 6, x and y being either integers or non-integers and z being from 0 to 6.
A range of zirconium salts which can be employed in antiperspirant compositions herein is represented by the following empirical general formula: ZrO(OH)2n-nzBz in which z is an integer or non-integer in the range of from 0.9 to 2.0, n is the valency of B, and B is selected from the group consisting of halide, sulphamate, sulphate and mixtures thereof; halide, especially chloride, being preferred.

It will be recognized that the above-identified formulae for aluminum and zirconium salts are greatly simplified and encompass compounds having coordinated and/or bound water in various quantities as well as polymeric species and mixtures and complexes.

Antiperspirant complexes based on the above-mentioned astringent salts are known and employable in the present invention. By way of example, complexes of aluminum, zirconium and amino acids such as glycine are disclosed in US. 3,792,068 (Luedders et a!). Certain of those complexes or complexes with related structures are commonly called ZAG in the literature. A preferred class of zirconium-based complexes which exhibit structures like ZAG comprise

zirconylchlorohydrate of empirical formula ZrO(OH)2-a Cl2-nH2O in which a is a non-integer in the range of from 1.5 to 1.87 and n is from 1 to 7, complexed with amino acids or other complexing agents. The especially preferred amino acid for complexing is glycine. Activated ZAG complexes can be employed as antiperspirant active in the present invention, such as the materials disclosed in US 5,486,347 (Callaghan et at).
Other antiperspirant actives which can be contemplated for use are astringent titanium salts.
the proportion of antiperspirant salt in the composition is normally calculated by weight on an anhydrous salt basis, i.e. excluding the weight of any water or complexing agent that may also be present. When present, the antiperspirant salt is typically used at a level of from 0.5-60%, particularly from 5 to 30% or 40% and especially from 5 or 10% to 30 or 35%.
The antiperspirant salts are often employed herein in particulate form, in compositions which do not comprise an aqueous phase. Such compositions are conveniently referred to as anhydrous or substantially anhydrous. The particle size of antiperspirant salts in such compositions often falls within the range of 1 to 200 micrometers. Smaller particles can be contemplated, e.g. 0.1 to 1 urn. Mean particle sizes for cast processes are often from 3 to 20pm.
It will be recognized that it is also possible to employ the antiperspirant active in aqueous solution, if desired. Such compositions normally adopt the form of water-in-oil emulsion Structuring is usually applied to the oil continuous phase, but the disperse phase can also structured too. The dispersed phase desirably has a droplet size chosen in the range of from 0.3 to 10 urn.
Hereian adeodorant...active ,indicates a material which is capable of killing microorganisms, particularly bacteria and/or hindering their growth, i.e. including bactericides and bacteriostats. Suitable deodorant actives include the aforementioned antiperspirant actives and additionally other inorganic or organic
materials or mixture of organic and inorganic actives. Amongst organic antimicrobial materials, one commonly recognized class comprises short chain monohydric alcohols, often considered to comprise up to 4 carbons, of which ethanol is especially prominent and isopropanol is sometimes employed to replace all or a fraction of the ethanol. A further class comprises polyhydric alcohols such as ethylene glycol or propylene glycol. It will be recognized that the two previous classes of anti-microbial materials can function also as a carrier for other components of the composition.
A further class of deodorant actives comprises chlorinated aromatics, of which materials known as triclosan TricTorban and Chlorhexidine warrant specific mention. Another class of deodorant actives comprises polymeric biguanide salts such as available under the trademark Cosmocil™. These two classes may be employed instead of or in addition to alcohols or polyols, and often in amounts selected in the range of from 0.001 to 1%, particularly from 0.1 to 0.5%.
Inorganic anti-microbial materials include zinc salts such as zinc oxide, hydroxide, carbonate, phenol sulphonate or ricinoleate, magnesium salts such as magnesium oxide, hydroxide, or carbonate, sodium bicarbonate, rare earth metal salts such as lanthanum oxide, hydroxide or carbonate or combinations of any two or more such salts.
A carrier fluid is a preferred component in the cosmetic compositions. Such a

material is a liquid material that is fluid at dispensing temperatures for the composition and can be gelled or otherwise structured by a structurant to provide a solid or semi-solid product at use temperature, i.e. typically below 40 and usually below 30° C. Where one or more of the remaining constituents is itself fluid at dispensing temperatures, such as a short chain monohydric alcohol or di or polyol having a melting point of below 40°C, it can provide the carrier function as well. The carrier can be a hydrophilic or hydrophobic liquid or a mixture of both. In many embodiments, the carrier fluid or the majority of the carrier fluid is hydrophobic, generally being an oil phase.

Liquid siloxanes and particularly volatile polyorganosiloxanes are suitable carrier fluids. The siloxanes can be linear or cyclic or mixtures thereof. Preferred cyclic siloxanes include polydimethylsiloxanes (cyclmethicones), particularly those having from 3 to 9 silicon atoms, and especially those having from 4 and/or 5 and/or 6 silicon atoms. Preferred linear siloxanes include polydimethylsiloxanes containing from 3 to 9 silicon atoms. The volatile silicones can also comprise branched linear or cyclic siloxanes such as the aforementioned linear or cyclic siloxanes substituted by one or more pendant --0-Si(CH3)3 groups. Examples of commercially available liquid siloxanes which are employable include Dow Coming 344, Dow Corning 345 and Dow Corning 244, DOW. Corning 245 and Dow Corning 246 (from Dow Corning Corporation); and Silicone 7207 and Silicone 7158 (from Union Carbide Corporation) and SF1202 (from General Electric [US]). Volatile silicones are often present in a proportion ranging from 20 to 50%.
The carrier employed in compositions herein can alternatively or preferably additionally comprise non-volatile silicone oils, which include polyalkyl siloxanes, polyalkylaryl siloxanes and polyethersiloxane copolymers. These can suitably be selected from dimethicone and dimethicone copolyols. Commercially available non- volatile silicone oils include Dow Corning 556 and Dow Corning 200 series. Non-volatile silicones are often present in not more than about 30%, and preferably from 1 to 15%. In many instances, when a non-volatile silicone oil is present, its weight ratio to volatile silicone oil is in the-range of from1;3 to 1:40.
To class as "volatile" such an oil should have a measurable vapour pressure at 20 or 25 C. Typically the vapour pressure of a volatile silicone lies in a range from 1 or10Pa to 2kPa at 25°C.
In the context of carrier fluids herein, liquid indicates a melting point of below 20°C. In practice, oils are chosen whichhave aboilling point of over 100°C and of over150°C.
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Non-silicone organic carrier fluids include liquid aliphatic hydrocarbons such as mineral oils or hydrogenated polyisobutene, often selected to exhibit a low viscosity. A further example of liquid hydrocarbons comprises polydecene. Other suitable carriers are liquid aliphatic esters containing at least one long chain alkyl group, such as esters derivable from C 1 -C 20 alkanols esterified with a C 8 to C 22 alkanoic acid or C 6 to C 10 alkanedioic acid. Suitable esters include isopropyl myristate, lauryl myristate, isopropyl palmitate, diisopropyl sebacate and diisopropyl adipate, of which isopropyl palmitate is particularly favoured. In further instances, the carrier fluid comprises aliphatic ethers derivable from at least one fatty alcohol, such as myristyl ether derivatives e.g. PPG-3 myristyl ether or lower alkyl ethers of polyglycols such as PPG-14 butyl ether. Mixtures of organic carriers can be employed.
Mixture of silicone and non-silicone carriers can suitably be employed herein.
The carrier or mixture of carrier employed in the present invention can be and in many effective compositions is anhydrous, i.e. contain no free water. Alternatively, if desired, the composition can comprise water in addition to siliceous and/or organic non-siliceous carriers, such as those indicated hereinbefore. Aqueous formulations in practice would normally further comprise an emulsifying surfactant, such as an anionic and/or nonionic surfactant. The choice of emulsifying surfactant or mixture of surfactants is usually matched to the nature of the emulsion being formed, in accordance with known principles. The weight ratio of aqueous phase to oil phase is often chosen within the range of from 10:1 to 1:20. The emulsion may comprise either an oil in water or a water in oil emulsion Where an ethulsion is employed, it can be convenient to prepare the emulsion as a separate step before it is mixed withjhe remaining constituents of the composition.
A structurant is a further preferred component on compositions used in the present invention. An organic structurant may be employed, for example a non-polymeric structurant, such as a linear fatty acid or salt thereof (often contaning

from 12 to_30 carbons such as stearic acid or sodium-stearate), or a linear fatty alcohol (typically insoluble in water and often containing from 12to 30 carbons, andparticularly from 14 to24 carbon.atoms such as cetyl alcohol, stearyl alcohol or behenyl alcohol). Fatty herein indicates a long chain aliphatic group, such as at least 12 linear carbons, which is frequently not branched (linear) and is saturated, but which can alternatively be branched (unless in the context branched is implicitly or explicitly excluded) and/or unsaturated. It is possible for the fatty acid to contain an hydroxyl group, as in 12-hydroxystearic acid, for example as part of a structurant combination, and to employ amido or ester derivatives thereof. Examples of suitable fatty alcohols include behenyl alcohol and sterols such as lanosterol. Structurants that are gellants, indicates that they gel the carrier fluid may also be employed. Suitable gellants can comprise dibenzylidene alditols, of which a preferred representative comprises dibenzylidene sorbitol. Further suitable gellants comprise selected n-acyl amino acid derivatives, including ester and amide derivatives, such as N-lauroyl glutamate dibutylamide (GP1), which gellants often contemplated in conjunction with hydroxystearic acid or an ester or amide derivative thereof. Still further gellants include amide derivatives of di or tribasic carboxylic acids, such as alkyl N,N dialkylsuccinimides-eg dodecyl N,N'-dibutylsuccinimide. Yet still further gellants for a water-immiscible liquid carrier include fatty acid esters of cellobiose, and especially cellobiose octanonanoate, possibly containing a fraction of heptylnonanoate.
Other organic structurants can comprise waxes such as paraffin waxes, hydrogenated castor oil, , Carnabau, beeswax, modified beeswaxes, microcrystalline waxes, polyethylene waxes and fatty ester derivatives of polyols, such as glycerol monostearate and related compounds and synthetic waxes obtained by esterifying glycerin with c16 to C30 fatty acids such as those obtainable under the trade mark Synchrowax™. Linear fatty alcohols of C12 to C30 and especially C14 to C24 as mentioned hereinabove are regarded herein within the class of waxes. Yet other suitable waxes include silicone waxes. It is especially desirable herein to employ a wax structurant or mixture of wax structurants. Mixtures of the organic structurants can be employed, such as
12
mixtures of a fatty acid/salt with a wax. Suitable choice of mixtures of structurants can reduce the visibility of antiperspirant/deodorant composition deposited in use on the skin.
Polymeric gellants may toe employed and may comprise Organo polysiloxane elastomers such as reaction products of a vinyl terminated polysiloxane and a cross linking agent or alkyl or alkyl polyoxyalkylene- terminated poly (methyl substituted) or poly(phenyl substituted) siloxanes. Other polymeric gellants can comprise polyacrylamides, polyacrylates or polyalkylene oxides, in part depending on whether the composition encompasses an aqueous phase in addition to a hydrophobic phase.
Where the composition comprises as a significant fraction of the carrier fluid a monohydric alcohol and/or a di or polyol, it can be convenient to employ as thickener, at least in part, a dibenzylidene derivative of a saccharide, and especially dibenzylidene sorbitol.
Where the composition comprises as a significant fraction of the carrier a volatile silicone, it can be preferable to employ a siliceous elastomer and in particular a crosslinked polyorganosiloxane often particulate, obtained by crosslinking a vinyl terminated siloxane polymer or by otherwise introducing cross linking. In operation, the particulate polyorganosiloxane absorbs the volatile silicone and is conveniently employed in a weight ratio to the volatile silicone of from 1:3 to 1:20.
In a thickeners may be employed, in particular siliceous and alumino-siliceous materials including silicas and clays. These materials can also function as suspending or bulking agents. Examples of suitable silicas include fumed silicas. Suitable clays include bentonites, hectorites and colloidal magnesium aluminium silicates. Commercially available clays are available under the trademark Veegum (Vanderbilt Co) and synthetic hectorites under the trademark Laponite (Laporte). It is preferable to employ montmorillonite clays which have been hydrophobically surface treated, for example by reaction with an amine.
13
Preferred hydrophobic- treated clays are available from Rheox, Inc under their Trademarks Bentone 38, Bentone 34, Pentone 27, Bentone 14 and Bentone LT.

Additional bulking agents or fillers may optionally be included in the cosmetic composition. Examples of such materials include particulate fillers including talc, sodium bicarbonate, starches, including corn starch, modified starches and mixtures thereof. The amount of such additional fillers/bulking agents is often not more than 15%, and preferably up to 10%, especially 1 to 5%.
fragrance is a preferred component of the compositions used as part of the present invention. A fragrance is generally added at from 0.1 to 2% and typically comprises a complex mixture of fragrance components.
improving the sensory properties of the sticks, it may be desirable to incorporate skin benefit agents into the formulation. Such agents are products which are deposited onto the skin when the deodorant or antiperspirant composition is applied to the skin and which impart to or maintain desirable properties for the skin. Moisturising components, such as emollient oils, are a particular example.
Wash-off agents may also be incorporated in the composition, to facilitate the removal of the composition from the skin on washing with water. Such agents may be selected from non-ionic surfactants and particularly nonionic ester or ether surfactants comprising a polyoxyethylene moiety, often containing from about 2 to 80, and especially 5 to 60 oxyethylene units and a hydrophobic alkyl, alkenyl or alkly moiety, normally containing from about 8 to 50 carbons and particularly from 10 to 30 carbons. Such non-ionic surfactants can also be derived from a polyhydroxy compound such as glycerol Examples of agents which offer wash-off benefits include ceteareth-10 to 25, steareth-10-25, and PEG-15-25 stearate or distearate. A material having both waxy and wash-oft properties, such as PEG-8 distearate can be employed.
14

Other skin benefit agents that may be included in the composition include:
Fats and oils including natural fats and oils such as jojoba, soyabean, rice bran,
avocado, almond, olive, sesame, persic, castor, coconut, mink, arachis, corn,
cotton seed, palm kernel, rapeseed, safflower seed and sunflower oils; cocoa
butter, beef tallow, lard; hardened oils obtained by hydrogenating the
aforementioned oils; and synthetic mono, di and triglycerides such as myristic acid
glyceride and 2-ethylhexanoic acid glyceride;
Waxes'such as carnauba, spermaceti, beeswax, lanolin and derivatives thereof;
Hydrophobic plant extracts;
Hydrocarbons such as liquid paraffins, petrolatum, microcrystalline wax, ceresin,
squalene and mineral oil;
Higher alcohols and fatty acids such as behenic, palmitic and stearic acids; lauryl,
cetyl, stearyl, oleyl, behenyl, cholesterol and 2- hexadecanol alcohols;
Esters such as cetyl octanoate, cetyl lactate, myristyl lactate, cetyl palmitate, butyl
myristate, butyl stearate, decyl oleate, cholesterol isostearate, myristyl myristate,
glyceryl laurate, glyceryl ricinoleate, glyceryl stearate, alkyl lactate, alkyl citrate,
alkyl tartrate, glyceryl isostearate, hexyl laurate, isobutyl palmitate, isocetyl
stearate, isopropyl isostearate, isopropyl laurate, isopropyl linoleate, isopropyl
myristate, isopropyl palmitate, isopropyl stearate, isopropyl adipate, propylene
glycol monolaurate, propylene glycol ricinoleate, propylene glycol stearate, and
propylene glycol isostearate;
Essential oils such as fish oils, mentha, jasmine, camphor, white cedar, bitter orang peel, ryu, turpentine, cinnamon, bergamont, citrus unshiu, calamus, pine, lavender bay, clove hiba, eucalyptus, lemon, starflower, thyme, peppermint, rose, sage, menthol, cineole, eugeniol, citral, citronelle, borneol, linalool, geraniol, evening primrose, camphor, thymol, spirantol, pinene, limonene and terpenoid oils;
Lipids such as cholesterol, ceramides, sucrose esters and pseudo- ceramides as described in EP-A-556 957;
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Vitamins such as vitamin A and E, and vitamin alkyl esters, including those
vitamin C alkyl esters;
Suncreens such as octyl methoxyl cinnamate (Parsol MCX) and butyl methoxy
benoylmethane (Parsol 1789);
Phospholipids; and
Mixtures of any two or more of the foregoing skin benefit agents.
It will be recognized that a number of the materials encompassed herein with the term skin benefit agents can contribute to the provision of other functions. It should be understood that in determining the proportion of such a material to incorporate, the calculation should take into account both desirable functions. For example, where the chosen emollient can also function as a structural, such as oleyl alcohol, the total proportion of that material should preferably be based on or similar to the larger proportion desired to provide one of the functions. For example, if 15% of oleyl alcohol is a desired proportion to provide structure and 5% of oleyl alcohol is sufficient to act as an "emollient", it would normally be convenient to employ about 15% oleyl alcohol, or possibly only a little more, in order to satisfy both functions.
The skin benefit agent such an emollient/oil is generally used in an amount from about 1 to 20%, preferably 1 to 15% by weight of the composition.
Other beneficial agents which can be incorporated comprise an anti-oxidant. Suitable examples include free radical inhibitors such as alkyl phenols e.g. butyl hydroxytoluene or ascorbic acid.
In thpse aspects of the present invention employjng injeclion of the cosmetic composition into a mould in order to form it into a stick prior to application of the coating compoaition, it is particularly desirable for the formulation to contain not more than 50% by weight of solid particulate material, which in practice is dispersed in a fluid carrier above its solidification temperature. Such solid particulate material is normally considered to include one or more of antiperspirant

active and/or filler such as talc, clay or silica. It is typically inorganic, though the antiperspirant can contain an organic complexing agent. in_many instances the proportion of particulate material is in the range of 0 to 35% by weight, and for antiperspirant formulations, especially 20 to 35% by weight. Naturally, the term particulates does not include organic gellants or waxes.
The coating
The coating for the cosmetic stick composition is preferably water-insoluble.
It is preferable that the coating is made of a material that inherently adheres to the outer surface of the cosmetic stick composition. By the choice of the organic coating materials described herein and the thinness of the coating and the abradable quality of the coating, the coating does not cause skin irritation during topical application of the product.
The thinness of the coating and/or the waxy nature of certain coating materials contribute to the capability of the coating to be abraded during normal use.
The material used as the coating has a melting point greater than 30°C, and preferably greater than 45°C.
Suitable materials are organic and may comprise water insoluble materials such as polymers and the combinations thereof, natural and synthetic waxes, polysaccharides and water insoluble salts of fatty acids that form inherent film on the outer surface of the said antiperspirant/deodorant stick. The coating-can also comprise any of the said organic materials with inorganic materials as diluents/fillers to modify the mechanical properties of the said coating.
The coating for the cosmetic stick composition preferably comprises one or more materials selected from natural polymers (including synthetic derivatives thereof), wholly synthetic polymers, or waxes. Polymers that are synthetic or synthetic

derivatives are particularly suitable, especially those having molecular weight of greater than 1600. Such particularly suitable polymers may optionally be accompanied in the coating by a diluent selected from natural or synthetic waxes, polysaccharides, or water insoluble salts of fatty acids whose melting point is greater than 30°C. Preferably, the diluent is a film-forming material.
The aforementioned particularly suitable polymers preferably have a water vapour
[cm3][Cm]
permeability coefficient of less than 5000 x 10'13 [Cm2 ]|s][pa] and more preferably
[Cm3\cm] less than 2000 x 10"13 [cm2[s][Pa]'where tCm3] is = Cm3(273,15K; 1,013 X 105
Pa) as outlined in "Polymer Handbook, 1989, Third edition, Eds. J.Brandrup and E.H. Immergut, (Wiley-lnterscience Publication), page VI/436". Such materials are preferably photo curable.
The thickness of the coating is often selected in conjunction with the nature of the coating material that is applied. The thickness is generally at least 5 microns on average. For polymeric coating materials, the coating is preferably in the form of a film whose thickness is maintained in the range from 5 to 1000 microns, more preferably from 10 to 100 microns, and most preferably from 20 or 30 to 60 microns. Where a wax is employed, and especially when it the principal constituent of the coating composition, i.e. in the absence or substantial absence of a polymer, the coating thickness is preferably at least 100 microns and in many embodiments is at least 200 microns. The coating thickness on application is usually not more than 3000 microns on average, and in many desirable embodits is nott greater than 2000 microns on average and in many embodiments significant property improvements over uncoated sticks are achievable with an average coating of no more than 1000 microns. A convenient average coating thickness for a number of wax-coated cosmetic products is from 330 to 750 microns.

It is possible to select materials for the coating which do not themselves bind to the composition, but can be made to do so by the addition of another material that provides this function.
Coatings can be formulated in a liquid solution or dispersion using a solvent or in a heated melt form consisting of a single or multiple polymeric/organic materials. The coating can be prepared using a composition of polymer(s) and/or various waxes. A tackifier, used to improve the adhesive properties of the coating composition, may also be advantageously employed. Appropriate combination of these components can be arrived at to provide desired workability and mechanical strength. The coating may be prepared using a base polymer alone or in combination with other components. The base polymer may be selected from polyacrylates, polymethylmethacrylate, poly styrene, poly(ethylene-co-vinyl acetate), poly(ethylene-co-acrylates), poly (ethylene-co-methacrylates), poly(styrene-co-acrylate), polyolefin, atactic poly(V-olefins), polyethylene, polypropylene, amorphous poly(V-olefins), polyimides, nylon, polyvinylchloride, polyethylene terephthalate, poly urethanes, epoxy resins.
The natural and synthetic waxes are optionally added to coating compositions employing the polymeric coating material to provide application viscosity control in molten state and act towards obtaining less dry tack and improving abradability/erodability. Such waxes can be selected from poly ethylene waxes, Fischer Tropsch waxes, microcrystalline waxes and paraffin waxes.
Tackifiers may increase the cohesive and binding characteristics of the film. These materials canoe chosen from hydrocarbon resins, petroleum C5-C9 resins, hydrogenated petroleum resins, aliphatic petroleum resins, alicyclic petroleum resins, coumarine petroleum resins, terpene based resins, stryrene resins, phenol based resins, ester gums, and rosins such as gum rosin and wood rosin.
Antioxidants are optionally added to the coating composition to prevent degradation in the molten state. These antioxidants can be chosen from the
following list: phenol base antioxidants such as 2,6-di-tert-butl-p-cresol, 2,2'-
methylenebis(4-methyl-6-tert-butylphenol), 4,4'-butylenebis(3-methyl-6-tert-
butylphenol), 4,4'-thiobis(3-methyl-6-tert-butylphenol), 2,2'-thiobis(4-methyl-6-tert-
butylphenol), stearyl-V-(3,5-di-tert-butyl-4-hydroxyphenol)propionate,
tetrakis(methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate)methane,
triethyene glycol, bis(3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, 1,3,5-
triethyl-2,4,6-tris(3,5-di-tert-butyl-4-hdroxybenzyl)benzene and 1,1,3-tris(2-methyl-
5-tert-butylphenol)-butane; amine base antioxidants such as phenyl-V-
naphthylamine, phenyl-a-naphthylamine, N-phenyl-N'-cyclohexyl-p-
phenylenediamine and N-isopropyl-N'-phenyl-phenylenediamine; phosphorous base antioxidants such as triisodecyl phosphite and 2,2'-methylenebis(4,6-di-tert-butylphenyl)ocyl phosphite; sulfur-based antioxidants such as 2,2'-thiobis(4-methyl-6-tert-butylphenol); and hydroquinone antioxidants such as 2,5-di-tert-amylhydroquinone.
The polymeric coating composition may also be prepared using a ultra-violet(IU V) cure composition involving acryiate-based oligomers, monomers and-photo-initiaters. Typical oligomers can be selected from the group urethane acrylate, polyester acrylate, polyether acrylate, poly butadiene acrylate and epoxy acrylate and their combinations to achieve the desired film properties. Description of such oligomers are presented in N.S. Allen, M. A. Johnson, P. Oldring (ed.) and M. S. Salim, Chemistry & Technology of UV&EB-Curing Formulations for Coatings, Inks & Paints, Vol. 2, SITA Technology, London 1991. Monomer can be chosen from the mono, di, tri, tetra and penta functional acrylates with various aliphatic or aromatic backbone. Typical examples of monomers include tripropylene glycol diacrylate (TPCDA) 16 hexanediol diacrylate (HDDA), propoxylated 3-glyceryl triacryiafe (GPTA), Isobornyl acrylate, 2rphenoxy ethyl acrylate (2-PEA)f Tridecyl acrylate (TDA), ethoxylated nonyl phenol acrylate (EONPA), ethoxylated pentaerythritol tetraacrylate (EOPETA), ethoxylated bisphenol A diacrylate (EOBPADA), trimethylolpropane trimethacrylate (TMPTA) and triacrylate, allyl methacrylate, stearyl acrylate and methacrylate, 1,3 butylene glycol dimethacrylate (1,3-BGDMA), ethylene glycol dimethacrylate (EGDMA),
cyclohexyl methacrylate (CHMA), glycidyl methacrylate (GMA), isodecyl acrylate (IDA), isooctyl acrylate, and polyethelene acrylate. Customary photoinitiators are aromatic ketone compounds; particularly suitable photoinitiators are benzophenone alkylbenzo-phenones (BABPi), Michler's ketone (MKi), anthrone halogenated benzophenones (AHBi), 2,4,6-trimethylbenzoyldiphenylphosphine oxide TMBDPPi), phenylglyoxylic esters, anthraquinone and its derivatives, benzil ketals (BKi), hydroxyalkylphenones (HAPi). Mixtures of photo-initiators may also be employed.
A particularly suitable photocurable coating material comprises a photo-curable silicone-based polymer, and particularly an epoxy-functional linear polydimethylsiloxane. It is particularly desirable to employ silicone catalyst therewith, such as particularly a catalyst which contains iodonium hexafluoroantimonate.
The film forming material can also comprise inorganic materials such as talc, silica, china clay, oxides, carbonates and chlorides of alkali or alkaline earth metals or transition metals and preferably they are salts of calcium or magnesium or zinc, the amount of any such inorganic materials permitting the organic materials to form a coating.
In many desirable embodiments of the instant invention, the coating material comprises a wax, such as one or more of the waxes that have been described hereinbefore, either in the context of structurants or gellants for the liquid carrier of the cosmetic stick composition or as diluents for the polymeric coating materials. It will be recognised that such materials have an especial appeal for the instant invention in view of their previous incorporation or proposed incorporation in cosmetic products because they do not irritate human skin.
Accordingly, suitable waxes as coating materials include linear fatty alcohols (often containing from 12 to 30 carbons, and particularly from 14 to 24 carbon atoms, such as cetyl alcohol, stearyl alcohol or behenyl alcohol), polyethylene
waxes, Fischer-Tropsch waxes, microcrystalline waxes, paraffin waxes, natural waxes derived from animal activity or plants or derivatives of waxy fractions thereof, such as spermaceti, beeswax, modified beeswaxes, candelilla wax, carnabau wax, waxes derived by hydrogenating glycerides oils such as hydrogenated castor oil and synthetic fatty acid ester derivatives of polyols, such as glycerol monostearate and related compounds and synthetic waxes obtained by esterifying glycerine with c16 to C30 fatty acids such as those obtainable under the trade mark Synchrowax™.
The waxes that are employable as coating material herein preferably have a melting point of at least 50°C, and generally not higher than 95°C. Many of the waxes have a lower melting point, that is to say up to 70°C, preferably in the range of 60 to 70°C and others have a higher melting point, that is say higher than 70°C, and preferably in the range of 75 to 85°C. Where the melting point of a wax is not provided in its safety data sheet or in a handbook on cosmetic ingredients it can be measured by a conventional method. Linear aliphatic alcohols and a number of synthetic fatty acid glycerides or of fractions of beeswax or synthesised beeswax fractions, have a lower melting point and others such as microcrystalline waxes and various hydrogenated plant oils, such as castor wax (have a higher melting point. It is preferable to employ a mixture of a lower melting point and a higher melting point wax as coating material, for example stearyl alcohol and castor wax (typical melting point of approximately 80°C), and preferably in a weight ratio of from 4:1 to 1:1. It will be recognised that many waxes and especially that which are derivable from natural sources often contain a mixture of compounds even if they nominally are a single compound such as stearyl alcohol. It will also be understood that the invention contemplates the incorporation, if desired, of compounds with a relatively low melting point, such as PEG-8 distearate, and especially if it has an additional beneficial property eg improving wash off.
Advantageously, a wax material is of especial suitability for coating a cosmetic stick employing a gelled water-immiscible carrier such as one or more of silicone
22

oils, hydrocarbon oils, or water-immiscible ester or ether oils. The waxes not only can offer compatibility with the liquid carrier which constitutes a significant fraction of the exposed surface of the cosmetic stick and a capability of adhering well thereto, but additionally act as emollients of the composition in their own right. Consequently such coating materials not only provide a protective covering for the otherwise exposed stick, making it easier and more pleasant to handle, but additionally supplement the emolliency of the product. The wax coating is also a comparatively non-abrasive material which can itself be abraded during topical application of the stick to human skin without causing the user discomfort.
In some desirable embodiments, the stick composition and the coating composition both comprise wax or a wax mixture. In very convenient embodiments, the same wax or wax mixture is employed in the coating and stick compositions, for example a combination of a fatty alcohol and a hydrogenated natural glyceride oil, eg castor wax. Whilst the wax materials may be common to both core and coating compositions, their weight ratio to the remaining constituents thereof, such as carrier liquids, in many instances is likely to be different.
The coating composition, and especially when it comprises a wax material, advantageously additionally comprises a carrier liquid. Very desirably, such carrier liquid comprises a volatile liquid such as a volatile silicone oil or hydrocarbon oil. After application of the coating composition to the stick, a fraction of the yolatile silicone can evaporate from the coating composition, whilst retaining a wax skin around the stick. The coating composition can alternatively or preferably additionally include one or more non-volatile or less volatile liquids such as non-volatile silicone oils, ester oils, ether oils, non-volatile hydrocarbon oils and branched aliphatic alcohols that have been described hereinbefore in more detail within the core stick composition.
The coating composition desirably contains at least 10% wax, preferably at least 20% wax and particularly at least 30% wax. Often the proportion of wax in the
coating composition is up to 70%, and in a number of beneficial compositions up to 60%, the liquid carrier usually providing the balance. The presence of the liquid carrier can assist the wax to spread evenly over the core composition surface. The selection of liquid carrier in the coating composition is at the discretion of the producer. In a number of embodiments it is desirable for it to contain a proportion of non-volatile oils in case at least a fraction of the volatile oils evaporate away, for example during storage, and for example in a weight ratio to the waxes of from 1:4 to 2:1.
The coating composition can additionally include a dye, preferably a dye that is soluble in water-immiscible liquids, thereby to show a user that the stick has a protective layer.
The relative weights of cosmetic and coating depend on the thickness of coating that is desired, which in turn often takes into account the coating material selected and the proprtion of active coating materials within the coating composition. In many instances, the ratio of core composition to total weight of coating composition is selected in the range of 2:1 to 500:1. For polymeric coatings a preferred range is from 100:1 to 250:1 and for wax coatings a preferred range is from 7:1 to 25:1, and in some instances from 9:1 to 15:1.
The product after it has been used will have an exposed top surface, even if the entire surface of the stick had initially been coated. The product may be employed together with cap dimensioned to fit closely over the top of the stick and engage the side of the stick, the cap advantageously being moulded from a thermoplastic such as polyethylene or polypropylene.
In a further aspect of the present invention there is provided a product comprising a stick composition coated with a coating composition according to the first aspect, having a closely fitting cap.
In a yet further aspect of the present invention, there is provided a kit of parts comprising a product comprising a stick composition coated with a coating composition according to the first aspect and a cap dimensioned to closely fit over the top of the stick.
The coating beneficially acts to retard loss of volatile materials from the stick within. However, during bulk transportation of the coated sticks, they can be subject to rough handling, and shaking and can be squashed together. In order to minimise or ameliorate such effects, the coated sticks can suitably be given a protective wrapping such as sleeve or pouch, optionally shrink-wrapped. Such a wrapping can also serve as a vehicle for displaying the brand of the product and carrying a label displaying useful information to the consumer or that which is required by law.
The coating may be applied to the stick composition as a liquid, possibly as a hot melt or as a solution in the carrier liquid. The coating composition can be applied to the stick composition by either dipping the stick into a body of the liquified coating composition or by spraying or painting the fluid coating composition onto the stick. The term painting includes use of a brush or sponge to apply a fluid by contact with or distribution across a surface. Whilst sufficient coating material may be applied at a single application, if the producer so chooses, and particularly for thicker coatings, a plurality of applications can be employed, thereby building up the coating successively.
Where the. coating material comprises a polymer, the coating composition may comprise a photo-curable component and a photo-initiator. In a second step, such axoating may be cured by irradiation with light of an appropriate wavelength in order to form a solid coating around the stick composition. UV-irradiation may be a particularly suitable form of light to cure the coating.
Where the coating material comprises a wax, the coating composition is normally liquified by heating the composition to a temperature at which the wax or the

highest melting point wax is molten, or if the composition additionally contains a carrier liquid, the temperature at which a solution of the coating material has been obtained. This temperature is commonly in the range of from 60 to 95°C. Advantageously, before applying the coating composition to the stick composition, it is cooled or allowed to cool to a temperature that is no more than 10°C higher than the set temperature of the coating composition, for example from 4 to 10°C higher. By so doing, application of the coating composition slightly softens the outer surface of the stick composition, thereby assisting the coating to bond with and hence adhere to the stick, but does not melt the stick. The resultant heat exchange tends to cool the coating composition and assist it to solidify. After the coating composition has been applied, the resultant product can be cooled or allowed to cool to ambient temperature. Cooling can be carried out in a conventional cooling chamber, such as one employing cooled air. The benefit of a coating compared with a conventional plastic barrel is that the thinner coating can permit faster heat transfer and therefore reduces_Cooling costs.
Having disclosed the invention in general terms, specific embodiments thereof will now be described in more detail by way of example only,
Examples , Example 1
-In Example 1, a typical deodorant stick having the composition presented in Table 1 was made in a conventional manner by blending together the liquid carriers, namely the propylene glycol which also functions as a deodorant active and liquid polyemethyne glycol, and the minor ingredients (which included fragrance and a supplementary deodorant active and any benefit agent as indicated hereinbefore) together with the gellant, sodium stearate at a temperature at which the gellant dissolved, and thereafter introducing the composition into 20g moulds and allowed to cool to ambient temperature and released from the mould.
Sticks were then coated by brushing(painting) each with.90 milligrams of a UV curable silicone polymer, a liquid mixture of 96% by weight of a commercially

available epoxy-functional linear polydimethysiloxane available under the trade name UV9400 from GE Silicones and 4% by.weight of a commercially available silicone catalyst available from GE silicones under the trade name UV9380c. The resultant coated sticks were irradiated with UV light using a 300 watt/inch medium pressure mercury vapour lamp until the coating had hardened (less than 1 second) and the stick had a hardened coat of 20 micron thickness.
Table1 Deodorant stick composition

Composition %wt.
Propylene Glycol 30.0
Polyethylene Glycol 25.0
Sodium Stearate 4.0
Minor ingredients 2.0
Water To 100
Determination of weight loss
The deodorant sticks of Example 1 of approximately 20g initial weight and uncoated sticks as control were weighed and placed in an oven set at 50°C. Their weight loss was monitored periodically up to 6 hours. The weight loss data at 6 hours is presented in Table 2.
Table 2

Examples Weight loss after 6 hours (g)
Example 1 (Control) 7.17
Example 2 (coated) 1.44
The data shows that the loss of volatiles/moisture was significantly reduced by providing the coating. The deodorant sticks had a very glossy and smooth finish and the perfume retention was also very good. Application of the coated sticks in a conventional manner onto skin showed that the coating was abraded away as the stick wore down and that no irritation was observed.
A similar result is obtained by coating the stick with a similar weight of a coating material comprising a monomer TPGDA, HDDA, GPTA, 2-PEA, TDA, EONPA, EOPETA, TMPTA, BGDMA, EGDMA, CHMA, GMA, or IDA in the presence on a photo-initiator BABPi, AHBi,, TMBDRPi, BKi or HAPi, as identified hereinbefore.
A similar result is obtained when the core stick composition incorporates ethanol and/or dipropylene glycol as a replacement for all or a fraction of the propylene glycol and/or liquid polyethylene glycol. Likewise, when all or a fraction of the gellant, sodium stearate is replaced with a potassium salt or a sodium or potassium salt of an alternative fatty acid, palmitate or myristate, and/or in whole or in part by a water-soluble polyacrylic acid or salt thereof. Likewise when the stick core comprises from 0.05 to 0.3% by weight of triclosan, chlorhexidine, and/or a bisbiguanide salt (Cosmocil™ CQ) as part of the minor ingredients.
Example 2
In this Example, an antiperspirant stick was coated with a coating as an alternative to a conventional preformed rigid barrel. The core sticks in this Example. were made by a conventional manufacture route for the composition shown in Table 3 in which a mixture of the carrier liquids and structurant (gellant) were heated an agitated vessel to the temperature at which a single phase was visible, i.e. the gellant had either dissolved or melted, the maximum temperature reached usually being in the range of from 60 to 95°C, and thereafter the mixture was allowed to cool to around 65 to 75°C if initially higher, at which temperature the antiperspirant active was introduced. The mixture continued to be agitated and allowed to cool until it had attained a temperature that was a few degrees C above its quiescent set temperature and then poured into 20g moulds. The stick
28

was allowed to cool to ambient temperature by which time it had set and was removed from the moulds.
Coating compositions according to Table 3 were made by mixing together the carrier liquids and the waxes in a vessel and heating the mixture to a temperature at which a single phase was observed, indicating that the wax was either molten or dissolved. This temperature approximated to the melting point of the highest melting wax, and was usually being in the range of from 60 to 95°C.
The coating composition was then allowed to cool to a temperature of around 55 to 60°C at which it was still mobile but was preferably several degrees C above the set temperature of the core stick, such as 5 to 10°C. The coating composition was then applied to the exterior sides and base of the stick by dipping it into the coating composition and withdrawing a wet coated stick. The weight ratio of core composition to adhering coating was 11.1, ie a coating of about 1.8g for each stick, covering the sides and base of the stick.. The coated stick, resting on the top surface to which coating had not been applied, was allowed to cool to ambient temperature, by which time the coating had solidified. The coating had an average thickness of about 450 microns.
Various properties of the coated and uncoated stick products were measured and summarised in Table 5.

Core Antiperspirant Stick Composition
Table 3

Ingredient % w/w
Cyclomethicone (D5) 33.45
PPG-14 Butyl Ether 17.50
Stearyl Alcohol 17.50
Hydrogenated Castor Oil 2.50
PEG-8 Distearate 2.00
AAZG Tetra Salt 24.00
Talc 2.00
Anti-oxidant 0.05
Perfume 1.00
Coating Compositions Table 4

Example No 2.1 2.2
Ingredient % w/w
Cyclomethicone 46.72 35.85
PPG-14 Butyl Ether 23.86 18.17
Stearyl Alcohol 23.86 36.45
Hydrogenated Castor Oil 3.41 5.19
PEG-8 Distearate 2.00 4.19
Dye 0.15 0.15

30

'
Product Properties-Table 5

Uncoated Comparison Product of Ex 2.1 Product of Ex 2.2
Evaporation of volatile fluids from stick Substantial evaporation from the core. Reduced evaporation from the core Virtually no evaporation from the core.
Degradation of stick by hand contact Noticeable Degradation {soft surface). Reduced degradation (soft surface). No degradation.
Stickiness when picked up Sticks to hand Sticks slightly to hand. Does not stick
Ease of grasping Difficult to hold. Easier to hold Easy to hold.
Rigidity of stick Less rigid than Ex 2.1 More rigid than comparison. Robust structure.
Application to armpit Messy, but no irritation observed Abrades during use and no irritation observed. Abrades during use and no irritation observed.

From Table 5, it is apparent that the products of Example 2.1 and 2.2 have properties significantly superior to those of the comparison stick. In particular, they lost less or substantially no volatile liquids from the core, thereby preserving the sensory properties of the stick much better than the comparison stick, they felt better during application, in that they did not stick to the hand, or only a little, they were more rigid, their surface was harder and they maintained the benefit during use, by virtue of the fact that the coating abrades away as the stick was consumed.
It will also be apparent that the properties of the coated stick of Example 2.2 were superior to those of 2.1.
An improvement in the properties of the coated stick can likewise be obtained compared with the uncoated stick as comparison when a wax coating is applied to a core stick in which other antiperspirant salts are substituted for all or a fraction of the AAZG tetra salt (an aluminium zirconium glycine complex) including aluminium chlorohydrate, activated aluminium chlorohydrate or aluminium zirconium chlorohydrate. An improvement in the properties of the coated stick can likewise be obtained when a wax coating is applied to a core stick in which other carrier liquids are substituted for all or a fraction of carrier fluids, namely a volatile hydrocarbon for all or a fraction of the volatile silicone oil and a non-volatile silicone oil such as DC200 (50 or 100 centistokes viscosity), or a mineral oil, or C12-15alkyl benzoate or a liquid aliphatic alcohol, such as isostearyl alcohol or octyldodecanol for all or a fraction of the PPG14 butyl ether). Likewise, a similar improvement can be obtained when an oil miscible polyhydric alcohol, glycerol is employed in an amount of up to 5% of the core composition. Likewise, a similar improvement is observable when 1/4 to 3/5ths of the water-immiscible oils are replaced by water together with from 0.1 to 3% by weight of an emulsifier such as steareth-2/steareth 20 mixture, thereby forming a water in oil emulsion in which the antiperspirant salt is dissolved in the aqueous phase.
32

Likewise, a similar improvement is observable when one or both waxes in the wax system described, stearyl alcohol and castor wax, is substituted in whole or in part by an alternative fatty alcohol such as cetyl or behenyl alcohol, beeswax, polyethylene wax, micro-crystalline wax or a synthetic glyceride wax (eg those available under the trade name Synchrowax). When making such substitutions, the skilled man should preferably substitute waxes within the same melting point range so as to retain a mixture of one above 70°C MP, especially 75 to 85°C and one from 60 to 70°C. Alternatively, the wax structurant can be substituted by from 10 to 15% by weight of a non-wax structurant such as GP1 and/or 12-hydroxystearic acid or cellobiose octanonanoate, with the balance comprising a further amount of the liquid carrier.
An improvement compared with the uncoated comparison can likewise be observed when the waxes in the coating composition are substituted by one or more other waxes in whole or in part and when the carrier liquids are substituted in whole in part by other carrier liquids or when the waxes are applied in molten form in the substantial absence of the carrier liquids.
In the preparation of the coating composition, a volatile hydrocarbon can be substituted for all or a fraction of the volatile silicone oil and a non-volatile silicone oil such as DC200 (50 or 100 centistokes viscosity), or a mineral oil, or C12-15alkyl benzoate or a liquid aliphatic alcohol, such as isostearyl alcohol or octyldodecanol for all or a fraction of the PPG14 butyl ether). Likewise, stearyl alcohol and castor wax, is substituted in whole or in part by an alternative fatty alcohol such as cetyl or behenyl alcohol, beeswax, polyethylene wax, micro-crystalline wax or a synthetic glyceride wax (eg those available under the trade name Synchrowax). When making such substitutions, the skilled man should preferably substitute waxes within the same melting point range so as to retain a mixture of one above 70°C MP, especially 75 to 85°C and one from 60 to 70°C.
In a further variation, a similar improvement in comparison with the uncoated stick is observable when the stick is dipped into a bath of the preformed liquid coating
composition, removed, excess liquid drains off back into the bath and the stick is cooled below the set temperature of the coating to form a solid coating.

We Claim :
1. A cosmetic stick product comprising a cosmetic stick composition and a coating for said composition that has a melting point of greater than 30°C, adheres to the external surface of the cosmetic stick composition, and is capable of being abraded during use.
2. A cosmetic stick product according to any of the preceding claims, wherein the coating is water-insoluble.
3. A product according to either preceding claim wherein the coating has a melting point o at least 45°C.
4. A product according to any preceding claim wherein the coating has a thickness of at least 5 microns.
5. A product according to any preceding claim, wherein the coating comprises a synthetic polymer, or synthetic derivative of a natural polymer.
6. A product according to claim 5, wherein the coating comprises a diluent for the polymer selected from natural or synthetic waxes, polysaccharides, or water insoluble salts of fatty acids whose melting point is greater than 30°C.
7. A product according to claim 5 or 6, wherein the polymer has a water vapour
[Cm3jcm] permeability coefficient of less than 5000 x 10-13 [Cm2 [s][Pa]l and more Preferably
[Cm3\Cm] less than 2000 x 10-13 [Cm2][S][pa] where [Cm3] is = Cm3(273,15K; 1,013 X 105
Pa).
8. A product according to any of claims 5 to 7, wherein the polymer has a molecular
weight of greater than 1600.
35

9. A cosmetic stick product according to any claims 1 to 8, wherein the coating is formed from a composition comprising a photo-curable component and a photo-initiator.
10. A cosmetic stick product according to claim 9, wherein the coating composition is UV-curable.
11. A product according to any of claims 5 to 10 wherein the coating has a thickness of up to 1000 microns and preferably from 10 to 100 microns.
12. A cosmetic stick product according to claim 11 wherein the coating is in the form of a film whose thickness is maintained in the range from 30 to 60 microns.
13. A product according to any of claims 1 to 4 wherein the coating comprises a wax.
14. A product according to claim 13 wherein the wax has a melting point of not higher than 95°C, and preferably in the range of from 50 to 85°C.
15. A product according to either of claims 13 or 14 wherein the coating comprises a mixture of at least one lower melting point wax, having a melting point in the range up to 70°C, and at least one higher melting point wax having a melting point in the range of from greater than 70°C.
16. A product according to claim 15 wherein at least one of the lower melting point waxes has a melting point of from 60°C to 70°C.
17. A product according to claim 15 or 16 wherein at least one of the higher melting point waxes has a melting point in the range of from 75 to 85°C.
18. A product according to any of claims 15 to 16 whereinthe lower melting point wax and higher melting point wax are present in a weight ratio of from 3:1 to 15:1, and preferably from 5:1 to 10:1.


19. A product according any of claims 15 to 18 wherein the lower melting point wax comprises a linear fatty alcohol containing from 14 to 24 carbon atoms or a mixture of any two or more such alcohols.
20. A product according to claim 19 wherein the fatty alcohol wax is selected from cetyl alcohol, stearyl alcohol, behenyl alcohol and mixtures of any two or more thereof.
21. A product according to any of claims 15 to 20 wherein the higher melting point wax comprises a hydrogenated fatty acid glyceride oil or a paraffin wax.
22. A product according to claim 20 whereinthe wax comprises a hydrogenated natural oil wherein the fatty acid contains 18 carbon atoms.
23. A product according to claim 19 or 20 wherein the wax is caster wax, carnabau wax, and/or candellila wax.
24. A product according to any one of claims 6 or 13 to 23 wherein the wax employed in the coating is also employed in the cosmetic stick composition.
25. A product according to any of claims 6 or 13 to 24 wherein the wax is applied in solution in a carrier liquid onto a core of the cosmetic composition.
26. A product according to claim 25 wherein the carrier liquid comprises one or more liquids selected from volatile silicone oils, volatile hydrocarbons, and polypropylene glycol ethers, or a mixture of two or more thereof.
27. A product according to claim 26 wherein the volatile silicone oil comprises a cyclomethicone containing 5 dimethylsiloxane units.
28. A product according to any of claims 25 to 27 wherein the wax comprises from 20 to 60% by weight of the coating composition, and preferably from 30 to 60%.
29. A product according to any of claims 25 to 28 wherein the coating composition comprises up to 40% by weight of a volatile liquid carrier.


30. A product according to any of claims 25 to 29 wherein the coating composition comprises one or more non-volatile liquid oils, preferably in a weight proportion ratio to the wax in the coating composition of from 1:4 to 2:1.
31. A product according to claim 30 whereinthe liquid oil is a polypropylene glycol ether.
32. A product according to any of claims 6 or 13 to 31, wherein the coating has a thickness of up to 3000 microns and preferably up to 2000 microns.
33. A product according to claim 32 wherein the coating has a thickness of at least 100 microns, and preferably at least 250 microns.
34. A product according to any preceding claim wherein the cosmetic stick composition comprises a cosmetic active, a liquid carrier for the cosmetic stick additive and a gellant for the liquid carrier.
35. A product according to claim 34 wherein the cosmetic active comprises an astringent antiperspirant salt or complex.
36. A product according to claim 35 wherein the astringent antiperspirant salt or complex comprises an aluminium chlorohydrate, an aluminium/zirconium chlorohydrate or a complex of aluminium/zirconium chlorohydrate with glycine.
37. A product according to any of claims 34 to 36 wherein the liquid carrier for the cosmetic active comprises one or liquids selected from the group of volatile silicone oils, non-volatile silicone oils, aliphatic hydrocarbon oils, branched aliphatic alcohol oils containing at least 12 carbon atoms, polypropylene glycol ether oils, and oils being aromatic ester derivatives of fatty acids, or liquids selected from liquid water-miscible mono- di- or trihydric aliphatic alcohols or a glycol oligomer.
38. A product according to claim 37 wherein the liquid carrier is anhydrous.


39. A product according to claim 38 wherein the liquid carrier is water-immiscible and the cosmetic active is suspended therein.
40. A product according to claim 39 wherein the liquid carrier for the cosmetic active is gelled with a wax.
41. A product according to claim 40 wherein the wax gellant comprises one or more naturally occurring or synthetic waxes or mixture of two or more thereof, said gellant having a melting point in the range of from 50 to 95°C, and preferably from 60 to 85°C.
42. A product according to claim 41 wherein the wax gellant comprises a linear fatty alcohol.
43. A product according to claim 41 or 42 wherein the wax gellant comprises a hydrogenated glyceride ester of a fatty acid, preferably an acid containing 18 carbon atoms or a micro-crystalline wax.
44. A product according to claim 43 wherein the wax gellant comprises caster wax.
45. A product according to claim 37 wherein the liquid carrier is water miscible and is gelled by a salt of an aliphatic fatty acid.
46. A product according to claim 45 wherein the salt is a sodium or potassium salt of a C16 to C22 aliphatic acid, preferably stearic acid.
47. A product according to claim 34 wherein the liquid carrier comprises a water-in-oil emulsion, the oil phase thereof being gelled.
48. A method of preparing a coated cosmetic stick product as claimed in claim 1 comprising the steps of forming a cosmetic stick composition, liquifying a coating composition comprising an organic coating material having a melting point of at least 30°C, applying the liquified coating composition to the stick composition in an amount sufficient to form a coating thereon.


49. A method according to claim 48 whereinthe coating material comprises a synthetic polymer, or a synthetic derivative of a natural polymer.
50. A method according to claim 49 whereinthe coating composition comprises a photo-curable component and a photo-initiator and after application of said coating composition to the stick composition, the coating composition is irradiated with light of an appropriate wavelength for initiating curing of the liquid coating composition, thereby forming a solid.
51. A method according to claim 48 whereinthe coating material comprises a wax.
52. A method according to claim 51 whereinthe coating composition is liquified by heating the wax above its melting point, and after application of the coating composition to the stick composition, the resultant coated composition is cooled or allowed to cool until the coating composition has solidified.
53. A method according to claim 52 whereina liquified coating composition is formed by dissolution of the wax in a liquid carrier, preferably at a temperature in the range of from 50 to 95°C.
54. A method according to claim 53 whereinthe coating composition is liquified by heating to a temperature in the vicinity of the wax or highest melting point wax if more than one wax is present.
55. A method according to any of claims 51 to 54 whereinthe wax comprises from 10 to 50% by weight of the coating composition, and preferably from 15 to 40%.
56. A method according to any of claims 51 to 55 wherein the wax comprises a linear fatty alcohol containing from 14 to 24 carbons and/or a glyceride fatty acid ester wax.
57. A method according to claim 56 wherein the wax is stearyl alcohol and/or caster wax.
58. A method according to any one of claims 51 to 56 wherein the coating composition comprises one or more volatile oils and one or more non-volatile liquid.


59. A method according to claim 58 wherein the volatile oil comprises pentacyclodimethicone and the non-volatile oil comprises a polypropylene glycol butyl ether.
60. A method according to any of claims 48 to 59 wherein the coating composition is applied by dipping the stick into a body of the liquified coating composition and thereafter withdrawing the stick and adhering coating composition from the body.
61. A method according to any of claims 48 to 59 wherein the liquified coating composition is sprayed onto the stick composition.
62. A method according to any of claims 48 to 59 wherein the liquified coating composition is painted onto the stick composition.
63. A method according to any of claims 48 to 62 wherein the coating composition is applied to a base surface and side surface of the stick composition.
64. A method according to claim 63 wherein the coating composition is absent from a top surface of the stick composition.
Dated this 31st day of October 2003
Dr.Sanchita Ganguli Of S.MAJUMDAR&CO. Applicant's Agents



Documents:

954-mum-2002 cancelled pages(9-11-2004).pdf

954-mum-2002 claims(9-11-2004).pdf

954-mum-2002 correspondence(ipo)(30-3-2007).pdf

954-mum-2002 correspondence1(31-10-2003).pdf

954-mum-2002 correspondence2(7-4-2006).pdf

954-mum-2002 form 1(1-9-2002).pdf

954-mum-2002 form 1(2-11-2002).pdf

954-mum-2002 form 19(31-10-2003).pdf

954-mum-2002 form 2(granted)(9-11-2004).pdf

954-mum-2002 form 3(1-11-2002).pdf

954-mum-2002 form 3(9-10-2003).pdf

954-mum-2002 petition under rule 138(9-11-2004).pdf

954-mum-2002 power of attorney(10-12-1998).pdf

954-mum-2002-claims(granted)-(9-11-2004).doc

954-mum-2002-form 2(granted)-(9-11-2004).doc


Patent Number 205367
Indian Patent Application Number 954/MUM/2002
PG Journal Number 26/2007
Publication Date 29-Jun-2007
Grant Date 30-Mar-2007
Date of Filing 01-Nov-2002
Name of Patentee HINDUSTAN UNILEVER LIMITED
Applicant Address HINDUSTAN LEVER HOUSE, 165/166, BACKBAY RECLAMATION, MUMBAI - 400 020, MAHARASHTRA, INDIA.
Inventors:
# Inventor's Name Inventor's Address
1 KAPOOR BIR, 2B, ANUSANDHAN, HLRC COMPLEX, CHAKALA, ANDHERI (EAST), MUMBAI - 400 099, MAHARASHTRA, INDIA.
PCT International Classification Number A 61 K 7/58
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA