Title of Invention	SKIN COATING COMPOSITIONS AND USES THEREOF
Abstract	A composition for coating skin comprising shellac, ethanol, castor oil,ethyl cellulose and fumed silica or nano zinc oxide, wherein the composition forms a long lasting waterproof flexible film on skin. The composition may include different ingredients for different applications. In one embodiment, the composition includes pigment and/or dye and may be used to coat a skin blemish such that the skin blemish blends in with the surrounding skin. In another embodiment, the composition includes a sunscreen agent and may be used as a sunscreen. In yet another embodiment, the composition includes a therapeutic agent for treating a disorder of the skin.

Title of Invention

SKIN COATING COMPOSITIONS AND USES THEREOF

Abstract

A composition for coating skin comprising shellac, ethanol, castor oil,ethyl cellulose and fumed silica or nano zinc oxide, wherein the composition forms a long lasting waterproof flexible film on skin. The composition may include different ingredients for different applications. In one embodiment, the composition includes pigment and/or dye and may be used to coat a skin blemish such that the skin blemish blends in with the surrounding skin. In another embodiment, the composition includes a sunscreen agent and may be used as a sunscreen. In yet another embodiment, the composition includes a therapeutic agent for treating a disorder of the skin.

Full Text	Skin Coating Composition and Uses Thereof Field of the Invention The present invention generally relates to a composition suitable for coating skin wherein the composition forms a durable waterproof flexible film on skin. The composition may include different ingredients for different applications. In one embodiment, the composition includes pigment and/or dye and may be used to coat a skin blemish such that the skin blemish blends in with the surrounding skin. In another embodiment, the composition includes a sunscreen agent and may be used as a sunscreen. In yet another embodiment, the composition includes a therapeutic agent for treating the skin. The subject matter of this application is related to the applicant's co-pending International Patent Application filed on 29 July 2005 and entitled "A Colour Compensating System" as well as Australian Provisional Patent Application No. 2004904225, the entire contents of which are herein incorporated by cross-reference. Background of the Invention Compositions for coating skin are known. Some are in the form of cosmetics for masking skin discoloration and skin blemishes, others are in the form of sunscreens for providing protection against the adverse effects of solar radiation, and yet others are in the form of skin care products for promoting healthy skin. For example, US 2,435,005 discloses skin protecting treatments or oils for use as an insect repellent or sunscreen agent. While US 2002/0197221 discloses cosmetic compositions for coating the skin. Some of the known skin coating compositions have the disadvantage that they are not long-lasting on the skin and may require frequent reapplication. Some compositions may be readily rubbed off the skin, whereas other compositions may be readily washed off the skin by way of sweat or when in contact with water. Summary of the Invention The present invention broadly relates to a coating composition that, when applied to the skin, forms a durable waterproof (i.e. impervious to water) flexible film. According to a first aspect of the present invention, there is provided a coating composition for skin, said composition comprising resin and flexibilizer, wherein upon application to skin, said composition forms a waterproof flexible film, characterised in that said composition comprises: about 5-30% w/w resin; about 50-80% w/w alcohol; about 7-42.5% w/w oil; about 2-10% w/w cellulosic preparation; and about 0.5-10% w/w inorganic thickener, wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to 15:21.25:1. According to a second aspect of the invention, there is provided a method for coating skin comprising the steps of: (i) coating skin with a composition comprising resin and flexibilizer; and (ii) allowing the composition to form a waterproof flexible film over the skin. Preferably, the flexible film is durable and is capable of remaining adhered to the skin for 1 to 3 days and more preferably up to about 5 days. The durability of the film will depend, inter alia, on the composition of the film, the properties of the skin and the environmental conditions to which the skin and film are subjected. The properties of the film will depend on the choice and quantity of resin and flexibilizer. Preferably, the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to 15:21.25:1. The properties of the film may be adjusted as necessary by changing the ingredients of the composition as well as by varying the relative amounts of ingredients. Other ingredients (eg. diluent, thickener and adhesive) may be added to the composition, and these will also affect the properties of the film. The composition may be, for example, in the form of a paste, cream, gel, liquid or aerosol. The film may be opaque, translucent or transparent. The composition may be used as a bandage or as artificial skin. The composition may include a diluent. Any suitable type of diluent may be used. The composition may include more than one type of diluent. Any suitable quantity of diluent may be used. For instance, the composition may contain little diluent if applied to the skin as a paste, e.g. using a brush or sponge. The composition may contain more diluent if applied to the skin as a liquid, e.g. using an airbrushing gun. The composition may be in the form of an aerosol, packaged under pressure with a suitable gaseous propellant. The diluent may be evaporative. Preferably, the diluent is an alcohol, such as ethanol, which will readily evaporate. The alcohol may be denatured or non-denatured. Preferably, ethanol (denatured with IPA) is present in the composition in an amount of about 20-80% weight by weight (w/w) . Any suitable type of resin may be used. The composition may include more than one type of resin. The resin may be of natural or synthetic origin. Any suitable quantity of resin may be used. The resin may be a natural alcohol-soluble resin such as shellac. Preferably, the resin is de-waxed (blonde) bleached shellac. More preferably, shellac is present in the composition in an amount of about 5-30% w/w. Any suitable type of flexibilizer (plasticiser) may be used to impart flexibility to the film and to hinder flaking of the film from the skin. The composition may include more than one type of flexibilizer. Any suitable quantity of flexibilizer may be used. A suitable flexibilizer may be oil. The oil may be of animal, vegetable, mineral or synthetic origin. The oil may be, for example, castor oil, pine oil, eucalyptus oil, ti-tree oil, rosehip oil or soya bean oil, or a mixture thereof. Preferably, oil is present in the composition in an amount of about 1- 70% w/w. More preferably, the oil is present in the composition in an amount of about 7- 42.5% w/w. The composition may include a cellulosic preparation. A cellulosic preparation is an example of another suitable flexibilizer. Any suitable type of cellulosic preparation may be used. The cellulosic preparation may comprise, for example, ethyl cellulose. Preferably, a cellulosic preparation is present in the composition in an amount of about 2-20% w/w. More preferably, a cellulosic preparation is present in the composition in an amount of about 2-10% w/w. The composition may include an adhesive for improving attachment of the film to the skin. Any suitable type of adhesive may be used. The composition may include more than one type of adhesive. Any suitable quantity of adhesive may be used. Preferably, the adhesive is ethyl cellulose or sucrose acetate isobutyrate. The composition may include an anti-agglomeration agent or dispersing agent. Any suitable agent or agents may be used. A suitable agent may be a blend of neutralised acid esters of phosphoric acid together with 2-(2-butoxyethoxy)ethanol. The composition may include thickener to increase the viscosity of the composition. Any suitable type of thickener may be used. The composition may include more than one type of thickener. Any suitable quantity of thickener may be used. A suitable thickener may include, for example, one or more of the following: a cellulosic preparation or an inorganic thickener such as silicon dioxide (fumed silica), castor oil derivatives, quaternium ammonium compound of bentonite, zinc stearate, nano zinc oxide (Zinclear™), inorganic thixotrope or modified clays. Preferably, inorganic thickener is present in the composition in an amount of about 0.5-10% w/w. The composition may include a preservative for extending the shelf life of the composition. Any suitable type of preservative may be used. The composition may include more than one type of preservative. Any suitable quantity of preservative may be used. A suitable preservative may include, for example, one or more of the following: butylated hydroxytoluene (BHT), butylated hydroxyanisole, hydroquinone and methylhydroquinone. Preferably, preservative is present in the composition in an amount of about 0.5-5% w/w. The film is preferably highly resistant to being washed off with water. The film may remain intact even when immersed in hot water. The film preferably bonds to the skin when immersed in saltwater. The film is preferably highly resistant to being rubbed off. The film may remain attached to the skin even if a shaver is scraped over the film. If more than one film layer is applied to the skin, the film layers may bond to one another. Preferably, the film enables the skin to breathe. It appears that the skin is able to breathe in that the film does not completely seal sweat pores of the skin as well as perhaps hair follicles of the skin. According to a preferred form of the invention, the coating composition comprises: about 5-30% w/w resin; about 50-80% w/w alcohol; about 7-42.5% w/w oil; about 2-10% w/w cellulosic preparation; and about 0.5-10% w/w inorganic thickener, wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to 15:21.25:1 Preferably, the resin is shellac, the alcohol is denatured ethanol, the oil is castor oil (7- 42.5% w/w) or a mixture of castor oil (7-42.4% w/w) and rosehip oil (0.1-5% w/w), the cellulosic preparation is ethyl cellulose, and the inorganic thickener is silicon dioxide. Preferably, the preferred form further comprises about 0.5-3% w/w preservative, such as BHT. The coating composition according to the first aspect of the invention may include different ingredients for different applications. For example, the coating composition may include at least one pigment and/or dye and be used to coat discoloured skin or a skin blemish such that the discoloured skin or skin blemish blends with the surrounding skin. The skin discoloration/skin blemish may be due to, for example, a birthmark, a mole, a basal cell carcinoma, vitiligo, a scar, a burn, pigmentation, acne, a vein, tattoo, eczema, dermatitis or bruising. Alternatively, such a composition may be used to simply change the skin colour of an individual. Alternatively or additionally, the coating composition may include at least one sunscreen agent and be used as a sunscreen. The sunscreen may protect individuals against premature ageing of skin, skin cancer and other harmful effects of solar radiation. Alternatively or additionally, the coating composition may include at least one therapeutic agent for preventing or treating disorders of the skin - for example, cuts, inflammation or infections. According to a third aspect of the present invention, there is provided a coloured coating composition for skin, said composition comprising resin, flexibilizer and pigment and/or dye, wherein upon application to skin, said composition forms a waterproof flexible coloured film. According to a preferred form of the invention, the coloured coating composition comprises: about 5-30% w/w resin; about 50-80% w/w alcohol; about 7-42.5% w/w oil; about 2-10% w/w cellulosic preparation; about 0.5-10% w/w inorganic thickener; and at least one pigment and/or dye, wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to 15:21.25:1. Any suitable type of pigment or dye may be used. The composition may include more man one type of pigment and/or dye, depending on the desired colour for the film. Any suitable quantity of pigment or dye may be used. Preferably, the pigment and/or dye is present in amount of about 0.01-10% w/w. A suitable pigment or dye may include, for example, one or more of the following: • Natural or synthetic iron oxides, black, red, yellow, brown, blended in various ratios. • Rutile titanium dioxide (micronised). • Zinc oxide (micronised). • Ultramarine blue (micronised). • Mixed metal oxide (cobalt) blue, black, turquoise, green. • Bon arymadide red pigments. • Bon red (calcium). • Rubine toners. • Arylamide yellows. • Transparent iron oxide pigments. • Phthalocyanine blues. • Dioxazine violets. • Pearlescent pigments in various colours, including white, copper, bronze. • Solvent dyes red, orange, yellow, blue, violet, brown, black. Preferably, the pigment is micronised and uniformly dispersed throughout the film. According to a fourth aspect of the present invention, there is provided a method for coating a skin discoloration or skin blemish such that the skin discoloration or blemish blends with the surrounding skin, said method comprising the steps of: (i) coating a skin discoloration or blemish with a composition comprising resin, flexibilizer, and pigment and/or dye; and (ii) allowing the composition to form a waterproof flexible coloured film over the skin discoloration or blemish. Preferably, said composition comprises: about 5-30% w/w resin; about 50-80% w/w alcohol; about 7-42.5% w/w oil; about 2-10% w/w cellulosic preparation; and about 0.5-10% w/w inorganic thickener, wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to 15:21.25:1. In another embodiment, the method comprises the pre-step of diluting the composition of in ethanol to produce a composition having 30% volume by volume (v/v) of the composition and 70% v/v ethanol and applying the diluted composition to the skin by spraying. The method may further comprise the step of (iii) applying a fixing powder to the coated skin discoloration of blemish to create a matte effect and to produce a more natural skin appearance. The fixing powder may be applied immediately after application of the composition and then reapplied after washing the skin. The application of a fixing powder is preferred if the composition is applied to the skin as a spray. The fixing powder may be of any suitable composition. The fixing powder can comprise talc, kaolin, zinc stearate, silicone oil (dimethicone), propylene glycol, and one or more preservatives such as, for instance, methylparaben, propylparaben, ethylparaben, butylparaben and mydazolidinyl urea. Talc and kaolin are opaquing agents. Zinc stearate is a lubricant. Dimethicone aids in spreading and rubbing of the powder on the skin and acts as a barrier preventing water penetration. Propylene glycol is a solvent. The fixing powder may also reduce any stickiness of an exposed surface of the film. In a preferred form the fixing powder comprises: about 93% w/w talc; about 4.7% w/w zinc stearate; about 1.4% w/w silicone oil; and about 0.9% w/w Unigerm G2™ (mixture of methylparaben, ethylparaben, propylene glycol and mydazolidinyl urea). The method preferably comprises the step of cleaning the skin (of natural oils, cosmetics etc.) before applying the coating composition. The method may comprise additional initial steps of: measuring at least one colour property of the skin discoloration or blemish; measuring at least one colour property of the surrounding skin; and using the measured at least one colour property of the skin discoloration or blemish and the at least one colour property of the surrounding skin to formulate a composition having a compensatory colour such that the skin discoloration or blemish when coated with the composition blends with the surrounding skin. Details of these additional initial steps may be found in the applicant's co-pending International Patent Application entitled "A Colour Compensating System" as well as in Provisional Patent Application No. 2004904225. The coloured coating composition preferably has a degree of translucency when applied to the skin discoloration or blemish and is not of identical colour to the surrounding skin. The present inventor has found that previous attempts to cover discoloured skin/blemishes by selecting an opaque cosmetic coating that is exactly the same colour as the surrounding skin and subsequently applying that coating to the skin discoloration/blemish to hide or mask the discoloration/blemish resulted in an unnatural and overly-made up, almost plasticky, look. Rather than simply trying to hide the discoloration/blemish, the translucent coating can have an additive or complementary effect with the underlying discoloration/blemish such that the discoloration/blemish, when coated, has a more natural appearance whilst still matching the appearance of the surrounding skin. According to a fifth aspect of the present invention, there is provided a sunscreen composition for skin, said composition comprising resin, flexibilizer and sunscreen agent, wherein upon application to skin, said composition forms a waterproof flexible film having a defined sun protection factor (SPF) value. Any suitable type of sunscreen agent may be used. The composition may include one or more sunscreen agents. Suitable sunscreen agents include titanium dioxide and zinc oxide. Preferably, the composition includes zinc oxide. If a clear sunscreen is desired, the zinc oxide may have a particle size of about 5-100 tun, and more preferably a particle size of about 20-40 tun. If a white opaque sunscreen is desired, the zinc oxide may have a larger particle size. The composition may have any defined SPF value, depending on its intended use. Preferably, the SPF value is at least 15 and more preferably at least 30. The composition may be applied to the skin in layers so as to exceed an SPF value of 30. A multilayer film may provide an SPF value of over 1000. In a preferred embodiment the at least one sunscreen agent is present in an amount of about 10 to 60 % w/w sunscreen agent. Preferably, the sunscreen film is durable in that it need not be reapplied for at least 1 to 3 days and up to about five days. The sunscreen composition may further include a pigment and/or dye for coating discoloured skin or skin blemishes, or for producing an opaque film. Individuals suffering from xeroderma pigmentosum may benefit from a long-lasting opaque sunscreen having a high SPF value. Such individuals may benefit from a multilayer film, whether the films are of the same composition or of different compositions. Preferably, the resin is shellac, the alcohol is denatured ethanol, the oil is castor oil (7- 20% w/w) or a mixture of castor oil (7-15% w/w) and rosehip oil (0.1-5% w/w), the cellulosic preparation is ethyl cellulose, and the sunscreen agent is zinc oxide having a particle size of between about 5-100 nm. Preferably, the preferred form further comprises about 0.5-1% w/w preservative, such as BHT. Preferably, the preferred form further comprises about 0.5-5% w/w vitamin E acetate. According to a sixth aspect of the present invention, there is provided a therapeutic composition for skin, said composition comprising resin, flexibilizer and at least one therapeutic agent, wherein upon application to skin, said composition forms a waterproof therapeutic flexible film. According to a seventh aspect of the present invention, there is provided a method for prevent or treating a disorder of the skin, said method comprising the step of applying to the skin a composition comprising resin, flexibilizer and at least one therapeutic agent, wherein upon application to skin, said composition forms a waterproof therapeutic flexible film. According to an eighth aspect of the present invention, there is provided the use of a composition in the preparation of a medicament for the prevention or treatment of a skin disorder, said composition comprising resin, flexibilizer and at least one therapeutic agent, wherein said composition forms a waterproof therapeutic flexible film when applied to skin. Any suitable type of therapeutic agent may be used. The composition may include one or more therapeutic agents. A suitable therapeutic agent may be an antimicrobial such as a bactericide or fungicide. Another suitable therapeutic agent may promote wound healing or have anti- inflammatory properties. Yet another suitable therapeutic agent may be a steroid for treating eczema or dermatitis. Such therapeutic agents are well known in the art. Examples of suitable therapeutic agents include vitamins, such as vitamin E, and rosehip oil. Examples of suitable growth factors are described, for example, in the specification published as WO92/09301 to the American National Red Cross. The therapeutic composition may include a pigment and/or dye for coating discoloured skin or skin blemishes and/or a sunscreen agent. As mentioned above, each of the above compositions may be formulated for application to the skin, for example, as a paste, cream, gel, liquid or aerosol. The composition may be applied by way of a sponge, brush or spray. The colour, strength, flexibility, plasticity, stability, opacity, viscosity may be readily optimised by adjusting the quantity of each ingredient of the composition. The same coating composition or different coating compositions may be applied to the skin in two or more layers, so as to achieve an optimal effect. The term "comprise" and variants thereof such as "comprising" and "comprised" are used herein to denote the inclusion of a stated integer or integers, unless in the context of usage an exclusive interpretation of a term is required. Preferred embodiments of the present invention will now be described by way of example with reference to the accompanying figures. Brief Description of the Drawings Figure 1 shows a patient having a port wine stain on her arm; Figure 2 shows the patient of Figure 1 treated with a coloured film forming coating composition according to an embodiment of the present invention; Figure 3 is a plot of percentage transmittance versus wavelength for a coloured film forming coating/sunscreen composition, according to an embodiment of the present invention; Figure 4 is a plot of percentage transmittance versus wavelength for a sunscreen composition, according to an embodiment of the present invention; and Figures 5 to 8 are plots of percentage transmittance versus wavelength for a coloured film forming coating/sunscreen composition, according to an embodiment of the present invention. Detailed Description of the Embodiments Example 1- Preparation of a Coloured Film Forming Coating Composition and Use Thereof for Coating a Skin Blemish This example describes the preparation of a coloured coating composition and its use in coating a skin blemish such that the blemish has the appearance of normal skin surrounding the blemish. The composition is particularly useful for coating birthmarks, moles, basal cell carcinomas, pigment-related disorders, scars, burns, acne, veins, tattoos, eczema, dermatitis and bruising. The composition can be specifically colour tailored to the needs of an individual. In order to formulate an appropriate coloured coating composition for coating a skin blemish, several readings of colour (hue, chroma and lightness) were taken from the skin blemish and normal skin surrounding the skin blemish using a spectrophotometer, the procedure for which is described in detail in the applicant's co-pending International Patent Application entitled "A Colour Compensating System". Colour readings were taken from the darkest region of the skin blemish and averaged. Colour readings were also taken from normal skin surrounding the skin blemish and averaged. A computer database was then interrogated. The computer database contained information relating to the colour properties of the blemish and the colour properties of the skin, as well as information relating to the appropriate colour properties of the coating composition to apply to the blemish such that the coated blemish exhibits the colour of the surrounding skin. The preferred coating compositions have a degree of translucency such that the colour of the coated skin blemish comprises the additive affects of the colour of the coating and the underlying colour of the blemish. The computer database may be used to select the coating composition. Alternatively, the computer database may provide information as to the desirable colour properties of the coating composition required to obtain the appropriate compensatory colour properties and this information may then be used to provide instructions to the user as to an appropriate coating composition to be prepared to obtain the desired compensatory colour properties. Once the desired coloured coating composition had been determined, that coating composition was made up from its basic ingredients. A. Preparation of Primary Pigment and Dye Dispersions A primary dispersion was made for each pigment and dye to be used in the coloured composition. Primary dispersions were prepared using one or more of the following pigments and dyes: • Natural or synthetic iron oxides, black, red, yellow, brown, blended in various ratios. • Rutile titanium dioxide (micronised). • Zinc oxide (micronised). • Ultramarine blue (micronised). • Mixed metal oxide (cobalt) blue, black, turquoise, green. • Bon arymadide red pigments. • Bon red (calcium). • Rubine toners. • Arylamide yellows. • Transparent iron oxide pigments. • Phthalocyanine blues. • Dioxazine violets. • Pearlescent pigments in various colours, including white, copper, bronze. • Solvent dyes red, orange, yellow, blue, violet, brown, black. Such pigments and dyes (as well as other suitable pigments and dyes) are available from Redox Chemicals, Polyimpex, Avlo Australia, Clariant Australia, Shepherd International, Merk Australia, Ravenswood Australia, HCA Colours, Degussa Australia, Quantum Chemicals, Multichem, GCI Chemicals Australia, Orica Australia, Tradechem, Johnson and Mathey, Elementis, Bayer Chemicals Pty Ltd, BASF Australia, DIC International, APS Australia, and OMYA Southern. Each pigment or dye 5-60% w/w was individually mixed to balance with castor oil (to 100% w/w) using a high-speed disperser for approximately 20 minutes, until the pigment or dye was fully wetted. Each resulting liquid/paste was processed through a bead mill or triple roll mill until a dispersion was achieved of less than 5 micron particle size. Particle size and agglomeration parameters were checked, e.g. using a Hegman guage. Each primary pigment and dye dispersion was then stored in a respective container. B. Preparation of a Film Forming Composition Shellac in both solid and liquid form is available from Redox Chemicals, Avlo Australia as well as from Quantum Chemicals. There are many forms of natural shellac available which vary greatly in colour from dark amber to blonde honey colour. A bleached version was used to give minimum coloration to the coloured composition. De-waxed (blonde) shellac flakes 28% w/w were added slowly to ethanol 55 % w/w and stirred until all of the shellac had dissolved. The solution was strained through a 10 micron filter cloth and then the following ingredients were added: ethyl cellulose 4% w/w; castor oil 4% w/w; inorganic thixotrope 4% w/w; preservatives 2% w/w and ethanol to 100% w/w. A suitable preservative may include, for example, one or more of the following: butylated hydroxytoluene, butylated hydroxyanisole, hydroquinone and methylhydroquinone. Such preservatives may be obtained from Multichem, Redox Chemicals, APS Australia, Quantum Chemicals and Johnson Mathey. The solution was stirred with gentle heating until all of the solids had dissolved and then strained through a 10 micron filter cloth. The solution was then stored in a container. C. Preparation of a Blend of Primary Pigment and Dye Dispersions From the computer/spectrophotometer prediction, select primary pigment and dye dispersions (from part A.) were blended together using a high-speed mixer until homogenous - eg. white ("vehicle") 86.16% w/w, black 03.77% w/w, red 0.58% w/w, yellow ochre 10.88% w/w. A white base (vehicle) was usually prepared from a dispersion of zinc oxide or titanium dioxide. D. Preparation of a Coloured Film Forming Coating Composition A final coloured film forming coating composition was then prepared as follows: blend of pigment and dye dispersions (from part C.) 12% w/w film forming composition (from part B.) 88% w/w The coloured coating composition was mixed vigorously and then applied to skin using brushing, sponging, or airbrushing. The composition may be readily applied to large skin areas using an airbrush gun. For airbrushing, the final coloured film forming composition 30% volume by volume (v/v) may be diluted in ethanol 70% v/v. The composition is preferably applied to the skin in a cross- hatching manner. For brushing or sponging, the coloured film forming composition may be used without dilution. A sponge having pores of an appropriate size can produce a stippled effect on the skin. The skin is usually cleaned with soapy water (to remove oils and chemical residues) prior to applying the composition. Figure 1 shows a patient 1 having a port wine stain 2 extending over her arm 3, neck 4 and chest 5. Figure 2 shows the same patient 1 but with the port wine stain 2 coated with a coloured composition prepared in accordance with Example 1. Example 2 - Preparation of a Coloured Film Forming Coating Composition and Use Thereof for Coating a Skin Blemish This example describes the preparation of another preferred coloured coating composition and its use in coating a skin blemish such that the blemish has the appearance of normal skin surrounding the blemish. A. Preparation of Primary Pigment and Dye Dispersions A primary dispersion was made for each pigment and dye to be used in the coloured composition. Primary dispersions were prepared as described in part A. of Example 1 except that the quantity of each pigment or dye varied and was balanced to 100% w/w using triple refined castor oil. B. Preparation of a Film Forming Composition A film forming composition was prepared as described in part B. of Example 1 except that the composition comprised: de-waxed (blonde) shellac flakes 10.37% w/w; ethyl cellulose 6.10% w/w; castor oil 13.34% w/w; rosehip oil 0.99% w/w; BHT 1.23% w/w; fumed silica 4.17% w/w; and ethanol 63.80% w/w. C. Preparation of a Blend of Primary Pigment and Dye Dispersions As described in part C. of Example 1, select primary pigment and dye dispersions (from part A.) were blended together. D. Preparation of a Coloured Film Forming Coating Composition A final coloured film forming coating composition was then prepared as follows: blend of pigment and dye dispersions (from part C.) 12% w/w film forming composition (from part B.) 88% w/w The coloured coating composition was mixed and then applied to skin using brushing, sponging, or airbrushing. For airbrushing, the final coloured film forming composition 30% volume by volume (v/v) may be diluted in ethanol 70% v/v. Shellac, ethyl cellulose, castor oil, fumed silica and ethanol are the minimum ingredients required to form the film. If a matte effect is desired, a fixing powder may be further applied to the coated skin. The fixing powder may be initially applied by sponge immediately after application of the composition and then reapplied after washing the skin. The fixing powder comprised: 92.99% w/w talc; 4.65% w/w zinc stearate; 1.43% w/w silicone oil; and 0.93 % w/w Unigerm G2™ (a mixture of methylparaben, ethylparaben, propylene glycol and mydazolidinyl urea). Example 3 - Preparation of a Film Forming Sunscreen Composition and the Use Thereof This example describes the preparation of a sunscreen composition and the use thereof. The sunscreen composition may protect individuals from premature ageing of skin, skin cancer and other harmful effects of solar radiation. Since the sunscreen film is long- lasting and has a high SPF value, it will be of particular use to those who are exposed to sunlight for long periods of time (e.g. sportsmen). A. Preparation of a Film Forming Composition De-waxed (blonde) shellac flakes 28% w/w were added slowly to ethanol 55% w/w and stirred until all of the shellac had dissolved. The solution was strained through a 10 micron filter cloth and then the following ingredients were added: ethyl cellulose 4% w/w; castor oil 4% w/w; inorganic thixotrope 4% w/w; preservatives 2% w/w and ethanol to 100% w/w. The solution was stirred with gentle heating until all of the solids had dissolved and then strained through a 10 micron filter cloth. The solution was stored in a container. B. Preparation of a Nano Zinc Oxide Dispersion Inorganic zinc oxide was milled to a nano scale, of less then 100nm particle size. High energy milling in dry form was used to induce chemical reactions during ball-powder collisions to form nano particles in a solid-state matrix. Agglomeration was minimized by ensuring that the particles were encapsulated on formation by a solid diluent phase (typically sodium chloride). The solid diluent phase was removed by a basic washing technique. This process formed equiaxed nano particles with a very narrow size distribution and very low levels of agglomeration. The solid diluent phase allowed the particles to be heat treated without any agglomeration occurring. The heat treatment step ensured the product was completely reacted, removed all residual chemicals and stabilized the surfaces of the particles. The stabilized surfaces assisted in decreasing the reactivity of the particles, which aided in the subsequent dispersion in both aqueous and non-aqueous phases, and limited the generation of free radicals. Zinc oxide becomes transparent when processed to nano particle size but still retains its UV protection properties. Due to its high refractive indices, zinc oxide blocks UV by both scattering and band gap absorption. A 20-40nm particle size was selected to provide broad spectrum UVB and UVA protection with maximum transparency in excess of 80%. Dry milled 20-40nm zinc oxide (40% w/w) was added slowly to the film forming composition of part A. (60% w/w) and mixed for a minimum of 20 minutes until a homogenous dispersion had been produced. The nano zinc oxide dispersion was then strained through a 10 micron filter cloth and stored in a container. C. Preparation of a Film Forming Sunscreen Composition A final film-forming sunscreen composition was made up as follows and mixed vigorously before application to the skin: film forming composition (of part A.) 70% w/w nano zinc oxide dispersion (of part B.) 30% w/w The sunscreen composition was then applied using brushing, sponging, or airbrushing. Example 4 - Sun Protection Factor Value of a Sunscreen Composition Containing Micronised Zinc Oxide A coloured coating composition was prepared in accordance with Example 1 and had the colour blend: blue 0.60% w/w; red 0.53% w/w; yellow ochre 11.25% w/w; and white (vehicle) 47.60% w/w. Since the vehicle comprised micronised zinc oxide, the coloured coating composition also functioned as a sunscreen. The composition was analysed using a Labsphere SPF Analyser with the following parameters: • substrate: MimSkin ® on quartz • film thickness: 2mg/cm2 • number of scans: 10 • UVBAJVA cut off: 320 nm The results are summarised in the following tables: Brush application - single film layer The final table shows that multilayering the film on skin (four layers) is likely to provide a much higher SPF value, in this case being 1216.65. Figure 3 is a plot of percentage transmittance versus wavelength for the composition when applied as four layers, and indicates that the composition can provide broad UV protection. Example 5 - Preparation of a Film Forming Therapeutic Sunscreen Composition This example describes the preparation of a preferred therapeutic sunscreen composition. A film forming composition was prepared as described in parts A., B. and C. of Example 3 except that the final composition comprised: de-waxed (blonde) shellac flakes 12.96% w/w; ethyl cellulose 7.79% w/w; castor oil 1.14% w/w; rosehip oil 0.50% w/w; BHT 1.00% w/w; vitamin E acetate 0.50% w/w; nano zinc oxide (Zinclear™) 34.40%; and ethanol 41.44% w/w. Shellac, ethyl cellulose, castor oil, nano zinc oxide and ethanol are the minimum ingredients required to form the film. The composition contains the therapeutic agent vitamin E acetate. This agent is an antioxidant and can decrease the effects of psoriasis, erythema and scaring from wounds. If desired, other therapeutic agents (eg. growth factors, steroids) may be used in the composition. Example 6 - Sun Protection Factor Value of a Sunscreen Composition Containing Nano Zinc Oxide The therapeutic composition of Example 5 was analysed using a Labsphere SPF Analyser with the following parameters: • substrate: MimSkin ® on quartz • rub-in method • film thickness: 2mg/cm2 • number of scans: 10 • UVB/UVA cut off: 320 nm The results are summarised in the following tables: Pre photodegradation Figure 4 is a plot of percentage transmittance versus wavelength for the composition when applied as a single layer. As for the composition tested in Example 4, multilayering the film on skin (four layers) provided a much higher (and more than additive) SPF value, and provided broad UV protection (results not shown). Example 7 - Sun Protection Factor Value of a Coloured Sunscreen Composition A coloured coating composition was prepared in accordance with Example 2. The following primary dispersions were prepared (to 100% w/w balance with castor oil): black iron oxide (Elementis) 25% w/w rubine bright red (Polyimpex) 20% w/w white (Tronox® CR-828 titanium dioxide) 50% w/w yellow ochre 40% w/w The following primary dispersion quantities were mixed with 44g of the film forming composition described in part B. of Example 2:0.03g black iron oxide; 0.07g rubine bright red; 4.13g white; and 1.48g yellow ochre. Since the composition contained titanium dioxide, the coloured coating composition could also function as a sunscreen. The composition, applied in 1 to 4 layers, was analysed using a Labsphere SPF Analyser with the following parameters: • substrate: MimSkin ® on quartz • rub-in method • film thickness: 2mg/cm2 • number of scans: 10 • UVB/UVA cut off: 320 nm The results are summarised in the following tables: Spray application - single film layer The final table shows that multilayering the film on skin (four layers) is likely to provide a much higher SPF value, in this case being 115.21. Figures 5-8 are plots of percentage transmittance versus wavelength for the composition when applied as one to four layers, respectively, and indicate that the composition can provide broad UV protection. The coating compositions as exemplified herein have one or more of the following advantages: • they are flexible and durable on the skin (typically lasting between 1 to 5 days); • they may be multilayered to provide a superior effect; • they are waterproof and sweat proof; • they remain intact even when immersed in hot water; • they bond to the skin when immersed in saltwater; • they remain intact even if clothing or a shaver is scraped over the film • they help keep the skin sterile; • they do not cause skin blemishes (pimples, breakouts); • they are gentle to the skin; and • they are easy to apply to the skin. Whilst the above has been given by way of illustrative example of the invention, many modifications and variations may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth. WE CLAIM: 1. A coating composition suitable for use on skin, said composition comprising: (a) 5-30% w/w resin; (b) 50-80% w/w alcohol; (c) 7-42.5% w/w oil; (d) 2-10% w/w cellulosic preparation; and (e) 0.5-10% w/w inorganic thickener, wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to 15:21.25:1. 2. The coating composition as claimed in claim 1, wherein the resin is a natural or synthetic resin. 3. The coating composition as claimed in claim 1, either of claims 1 or 2, wherein the oil is selected from castor oil, pine oil, eucalyptus oil, ti-tree oil, rosehip oil, soya bean oil or a mixture thereof. 4. The coating composition as claimed in any one of claims 1 to 3, wherein the inorganic thickener is selected from compounds such as silicon dioxide (fumed silica), castor oil derivatives, quaternium ammonium compound of bentonite, zinc stearate, nano zinc oxide, inorganic thixotrope or modified clays. 5. The coating composition as claimed in the preceding claims, wherein the resin is shellac, the alcohol is ethanol, the oil is a mixture of 7 to 42.4% w/w castor oil and 0.1 to 5% w/w rosehip oil, the cellulosic preparation is ethyl cellulose, and the inorganic thickener is silicon dioxide. 6. The coating composition as claimed in any one of claims 1 to 5, wherein the coating composition further comprises one or more pigments, or one or more dyes, or one or more pigments and one or more dyes. 7. The coating composition as claimed in claim 6, wherein the coating composition comprises 0.01 to 10% w/w pigment, or dye or pigment and dye. 8. A coating composition suitable for use on skin comprising 30% volume by volume (v/v) of the composition of claim 7 and 70% v/v ethanol. 9. The coating composition as claimed in any one of claims 1 to 7, wherein the coating composition further comprises one or more sunscreen agents. 10. The coating composition as claimed in claim 9, wherein the coating composition comprises 10 to 60% w/w sunscreen agent. 11. The coating composition as claimed in claim 10, wherein the sunscreen agent comprises zinc oxide. 12. The coating composition as claimed in either of claims 10 or 11, wherein the resin is shellac, the alcohol is ethanol, the oil is a mixture of 7 to 15% w/w castor oil and 0.1 to 5% w/w rosehip oil, the cellulosic preparation is ethyl cellulose, and the sunscreen agent is zinc oxide having a particle size of between 5 to 100 nm. 13. The coating composition as claimed in any one of claims 1 to 7 or 9 to 12, wherein the coating composition further comprises one or more therapeutic agents. 14. The coating composition as claimed in claim 13, wherein the therapeutic agent is selected from antimicrobial agents such as bactericide, fungicide; wound healing agents, anti-inflammatory agents, steroids. 15. The coating composition as claimed in claim 13, wherein the therapeutic agent comprises 0.5 to 5% w/w vitamin E acetate. 16. The coating composition as claimed in claim 5 in the formation of a waterproof flexible coloured film for coating a skin discoloration or skin blemish,, said coating composition comprising an effective amount of one or more pigments, or one or more dyes, or one or more pigments and one or more dyes. 17. The coating composition as claimed in claim 16, wherein said coating composition further comprises a sunscreen agent or a therapeutic agent or a sunscreen agent and a therapeutic agent. 18. The coating composition as claimed in either of claims 16 or 17, wherein the skin discoloration or blemish is selected from the group consisting of a birthmark, a mole, a basal cell carcinoma, vitiligo, a scar, a burn, pigmentation, acne, a vein, tattoo, eczema, dermatitis and bruising. 19. The coating composition as claimed in any one of claims 16 to 18 wherein the coating composition is formulated to enable the use of a fixing powder on the coated skin discoloration or blemish. 20. The coating composition as claimed in claim 19, wherein the fixing powder comprises: (a) 93.0% w/w talc; (b) 4.7% w/w zinc stearate; (c) 1.4% w/w silicone oil; and (d) 0.9% w/w preservative. 21. The coating composition as claimed in any one of claims 16 to 20, is formulated as a paste. 22. The coating composition as claimed in any one of claims 16 to 21, wherein the coating composition of claim 6 is formulated for dilution in ethanol prior to use to produce a composition having 30% volume by volume (v/v) of the coating composition and 70% v/v ethanol and wherein the diluted coated composition is suitable for administration to the skin by spraying. 23. The coating composition as claimed in any one of claims 9 to 13 in the preparation of a waterproof flexible film, said coating composition comprising an effective amount of one or more therapeutic agents, or one or more sunscreen agents, or one or more therapeutic agents and one or more sunscreen agents for the prevention or treatment of a disorder of the skin wherein, upon application to skin, said coating composition forms a waterproof flexible film. 24. The coating composition as claimed in claim 23, wherein said disorder of the skin is xeroderma pigmentosum. ABSTRACT A composition for coating skin comprising shellac, ethanol, castor oil,ethyl cellulose and fumed silica or nano zinc oxide, wherein the composition forms a long lasting waterproof flexible film on skin. The composition may include different ingredients for different applications. In one embodiment, the composition includes pigment and/or dye and may be used to coat a skin blemish such that the skin blemish blends in with the surrounding skin. In another embodiment, the composition includes a sunscreen agent and may be used as a sunscreen. In yet another embodiment, the composition includes a therapeutic agent for treating a disorder of the skin.

Full Text

Skin Coating Composition and Uses Thereof
Field of the Invention
The present invention generally relates to a composition suitable for coating skin
wherein the composition forms a durable waterproof flexible film on skin. The composition
may include different ingredients for different applications. In one embodiment, the
composition includes pigment and/or dye and may be used to coat a skin blemish such that the
skin blemish blends in with the surrounding skin. In another embodiment, the composition
includes a sunscreen agent and may be used as a sunscreen. In yet another embodiment, the
composition includes a therapeutic agent for treating the skin.
The subject matter of this application is related to the applicant's co-pending
International Patent Application filed on 29 July 2005 and entitled "A Colour Compensating
System" as well as Australian Provisional Patent Application No. 2004904225, the entire
contents of which are herein incorporated by cross-reference.
Background of the Invention
Compositions for coating skin are known. Some are in the form of cosmetics for
masking skin discoloration and skin blemishes, others are in the form of sunscreens for
providing protection against the adverse effects of solar radiation, and yet others are in the
form of skin care products for promoting healthy skin. For example, US 2,435,005 discloses
skin protecting treatments or oils for use as an insect repellent or sunscreen agent. While US
2002/0197221 discloses cosmetic compositions for coating the skin.
Some of the known skin coating compositions have the disadvantage that they are not
long-lasting on the skin and may require frequent reapplication. Some compositions may be
readily rubbed off the skin, whereas other compositions may be readily washed off the skin by
way of sweat or when in contact with water.

Summary of the Invention
The present invention broadly relates to a coating composition that, when applied to
the skin, forms a durable waterproof (i.e. impervious to water) flexible film.
According to a first aspect of the present invention, there is provided a coating
composition for skin, said composition comprising resin and flexibilizer, wherein upon
application to skin, said composition forms a waterproof flexible film, characterised in that
said composition comprises:
about 5-30% w/w resin;
about 50-80% w/w alcohol;
about 7-42.5% w/w oil;
about 2-10% w/w cellulosic preparation; and
about 0.5-10% w/w inorganic thickener,
wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to
15:21.25:1.
According to a second aspect of the invention, there is provided a method for coating
skin comprising the steps of:
(i) coating skin with a composition comprising resin and flexibilizer; and
(ii) allowing the composition to form a waterproof flexible film over the skin.
Preferably, the flexible film is durable and is capable of remaining adhered to the skin
for 1 to 3 days and more preferably up to about 5 days. The durability of the film will depend,
inter alia, on the composition of the film, the properties of the skin and the environmental
conditions to which the skin and film are subjected.
The properties of the film will depend on the choice and quantity of resin and
flexibilizer. Preferably, the ratio of resin to oil to cellulosic preparation ranges from
0.5:0.7:1 to 15:21.25:1. The properties of the film may be adjusted as necessary by changing
the ingredients of the composition as well as by varying the relative amounts of ingredients.
Other ingredients (eg. diluent, thickener and adhesive) may be added to the composition, and
these will also affect the properties of the film.
The composition may be, for example, in the form of a paste, cream, gel, liquid or
aerosol. The film may be opaque, translucent or transparent. The composition may be used as a
bandage or as artificial skin.

The composition may include a diluent. Any suitable type of diluent may be used.
The composition may include more than one type of diluent. Any suitable quantity of diluent
may be used. For instance, the composition may contain little diluent if applied to the skin as a
paste, e.g. using a brush or sponge. The composition may contain more diluent if applied to the
skin as a liquid, e.g. using an airbrushing gun. The composition may be in the form of an
aerosol, packaged under pressure with a suitable gaseous propellant. The diluent may be
evaporative. Preferably, the diluent is an alcohol, such as ethanol, which will readily evaporate.
The alcohol may be denatured or non-denatured. Preferably, ethanol (denatured with IPA) is
present in the composition in an amount of about 20-80% weight by weight (w/w) .
Any suitable type of resin may be used. The composition may include more than one
type of resin. The resin may be of natural or synthetic origin. Any suitable quantity of resin
may be used. The resin may be a natural alcohol-soluble resin such as shellac. Preferably, the
resin is de-waxed (blonde) bleached shellac. More preferably, shellac is present in the
composition in an amount of about 5-30% w/w.
Any suitable type of flexibilizer (plasticiser) may be used to impart flexibility to the
film and to hinder flaking of the film from the skin. The composition may include more than
one type of flexibilizer. Any suitable quantity of flexibilizer may be used. A suitable
flexibilizer may be oil. The oil may be of animal, vegetable, mineral or synthetic origin. The
oil may be, for example, castor oil, pine oil, eucalyptus oil, ti-tree oil, rosehip oil or soya bean
oil, or a mixture thereof. Preferably, oil is present in the composition in an amount of about 1-
70% w/w. More preferably, the oil is present in the composition in an amount of about 7-
42.5% w/w.
The composition may include a cellulosic preparation. A cellulosic preparation is an
example of another suitable flexibilizer. Any suitable type of cellulosic preparation may be
used. The cellulosic preparation may comprise, for example, ethyl cellulose. Preferably, a
cellulosic preparation is present in the composition in an amount of about 2-20% w/w. More
preferably, a cellulosic preparation is present in the composition in an amount of about 2-10%
w/w.
The composition may include an adhesive for improving attachment of the film to the
skin. Any suitable type of adhesive may be used. The composition may include more than one
type of adhesive. Any suitable quantity of adhesive may be used. Preferably, the adhesive is
ethyl cellulose or sucrose acetate isobutyrate.

The composition may include an anti-agglomeration agent or dispersing agent. Any
suitable agent or agents may be used. A suitable agent may be a blend of neutralised acid esters
of phosphoric acid together with 2-(2-butoxyethoxy)ethanol.
The composition may include thickener to increase the viscosity of the composition.
Any suitable type of thickener may be used. The composition may include more than one type
of thickener. Any suitable quantity of thickener may be used. A suitable thickener may
include, for example, one or more of the following: a cellulosic preparation or an inorganic
thickener such as silicon dioxide (fumed silica), castor oil derivatives, quaternium ammonium
compound of bentonite, zinc stearate, nano zinc oxide (Zinclear™), inorganic thixotrope or
modified clays. Preferably, inorganic thickener is present in the composition in an amount of
about 0.5-10% w/w.
The composition may include a preservative for extending the shelf life of the
composition. Any suitable type of preservative may be used. The composition may include
more than one type of preservative. Any suitable quantity of preservative may be used. A
suitable preservative may include, for example, one or more of the following: butylated
hydroxytoluene (BHT), butylated hydroxyanisole, hydroquinone and methylhydroquinone.
Preferably, preservative is present in the composition in an amount of about 0.5-5% w/w.
The film is preferably highly resistant to being washed off with water. The film may
remain intact even when immersed in hot water. The film preferably bonds to the skin when
immersed in saltwater. The film is preferably highly resistant to being rubbed off. The film
may remain attached to the skin even if a shaver is scraped over the film. If more than one film
layer is applied to the skin, the film layers may bond to one another. Preferably, the film
enables the skin to breathe. It appears that the skin is able to breathe in that the film does not
completely seal sweat pores of the skin as well as perhaps hair follicles of the skin.
According to a preferred form of the invention, the coating composition comprises:
about 5-30% w/w resin;
about 50-80% w/w alcohol;
about 7-42.5% w/w oil;
about 2-10% w/w cellulosic preparation; and
about 0.5-10% w/w inorganic thickener,
wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to
15:21.25:1

Preferably, the resin is shellac, the alcohol is denatured ethanol, the oil is castor oil (7-
42.5% w/w) or a mixture of castor oil (7-42.4% w/w) and rosehip oil (0.1-5% w/w), the
cellulosic preparation is ethyl cellulose, and the inorganic thickener is silicon dioxide.
Preferably, the preferred form further comprises about 0.5-3% w/w preservative, such
as BHT.
The coating composition according to the first aspect of the invention may include
different ingredients for different applications. For example, the coating composition may
include at least one pigment and/or dye and be used to coat discoloured skin or a skin blemish
such that the discoloured skin or skin blemish blends with the surrounding skin. The skin
discoloration/skin blemish may be due to, for example, a birthmark, a mole, a basal cell
carcinoma, vitiligo, a scar, a burn, pigmentation, acne, a vein, tattoo, eczema, dermatitis or
bruising. Alternatively, such a composition may be used to simply change the skin colour of an
individual.
Alternatively or additionally, the coating composition may include at least one
sunscreen agent and be used as a sunscreen. The sunscreen may protect individuals against
premature ageing of skin, skin cancer and other harmful effects of solar radiation.
Alternatively or additionally, the coating composition may include at least one therapeutic
agent for preventing or treating disorders of the skin - for example, cuts, inflammation or
infections.
According to a third aspect of the present invention, there is provided a coloured
coating composition for skin, said composition comprising resin, flexibilizer and pigment
and/or dye, wherein upon application to skin, said composition forms a waterproof flexible
coloured film. According to a preferred form of the invention, the coloured coating
composition comprises:
about 5-30% w/w resin;
about 50-80% w/w alcohol;
about 7-42.5% w/w oil;
about 2-10% w/w cellulosic preparation;
about 0.5-10% w/w inorganic thickener; and
at least one pigment and/or dye,
wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to
15:21.25:1.

Any suitable type of pigment or dye may be used. The composition may include more
man one type of pigment and/or dye, depending on the desired colour for the film. Any
suitable quantity of pigment or dye may be used. Preferably, the pigment and/or dye is present
in amount of about 0.01-10% w/w. A suitable pigment or dye may include, for example, one or
more of the following:
• Natural or synthetic iron oxides, black, red, yellow, brown, blended in various
ratios.
• Rutile titanium dioxide (micronised).
• Zinc oxide (micronised).
• Ultramarine blue (micronised).
• Mixed metal oxide (cobalt) blue, black, turquoise, green.
• Bon arymadide red pigments.
• Bon red (calcium).
• Rubine toners.
• Arylamide yellows.
• Transparent iron oxide pigments.
• Phthalocyanine blues.
• Dioxazine violets.
• Pearlescent pigments in various colours, including white, copper, bronze.
• Solvent dyes red, orange, yellow, blue, violet, brown, black.
Preferably, the pigment is micronised and uniformly dispersed throughout the film.
According to a fourth aspect of the present invention, there is provided a method for coating a
skin discoloration or skin blemish such that the skin discoloration or blemish blends with the
surrounding skin, said method comprising the steps of:
(i) coating a skin discoloration or blemish with a composition comprising resin,
flexibilizer, and pigment and/or dye; and
(ii) allowing the composition to form a waterproof flexible coloured film over the
skin discoloration or blemish.
Preferably, said composition comprises:
about 5-30% w/w resin;
about 50-80% w/w alcohol;

about 7-42.5% w/w oil;
about 2-10% w/w cellulosic preparation; and
about 0.5-10% w/w inorganic thickener,
wherein the ratio of resin to oil to cellulosic preparation ranges from 0.5:0.7:1 to
15:21.25:1.
In another embodiment, the method comprises the pre-step of diluting the composition of
in ethanol to produce a composition having 30% volume by volume (v/v) of the
composition and 70% v/v ethanol and applying the diluted composition to the skin by
spraying.
The method may further comprise the step of (iii) applying a fixing powder to the
coated skin discoloration of blemish to create a matte effect and to produce a more natural skin
appearance. The fixing powder may be applied immediately after application of the
composition and then reapplied after washing the skin. The application of a fixing powder is
preferred if the composition is applied to the skin as a spray.
The fixing powder may be of any suitable composition. The fixing powder can
comprise talc, kaolin, zinc stearate, silicone oil (dimethicone), propylene glycol, and one or
more preservatives such as, for instance, methylparaben, propylparaben, ethylparaben,
butylparaben and mydazolidinyl urea. Talc and kaolin are opaquing agents. Zinc stearate is a
lubricant. Dimethicone aids in spreading and rubbing of the powder on the skin and acts as a
barrier preventing water penetration. Propylene glycol is a solvent. The fixing powder may
also reduce any stickiness of an exposed surface of the film.
In a preferred form the fixing powder comprises:
about 93% w/w talc;
about 4.7% w/w zinc stearate;
about 1.4% w/w silicone oil; and
about 0.9% w/w Unigerm G2™ (mixture of methylparaben, ethylparaben, propylene
glycol and mydazolidinyl urea).
The method preferably comprises the step of cleaning the skin (of natural oils,
cosmetics etc.) before applying the coating composition.
The method may comprise additional initial steps of:

measuring at least one colour property of the skin discoloration or blemish;
measuring at least one colour property of the surrounding skin; and
using the measured at least one colour property of the skin discoloration or blemish
and the at least one colour property of the surrounding skin to formulate a composition having
a compensatory colour such that the skin discoloration or blemish when coated with the
composition blends with the surrounding skin.
Details of these additional initial steps may be found in the applicant's co-pending
International Patent Application entitled "A Colour Compensating System" as well as in
Provisional Patent Application No. 2004904225.
The coloured coating composition preferably has a degree of translucency when
applied to the skin discoloration or blemish and is not of identical colour to the surrounding
skin. The present inventor has found that previous attempts to cover discoloured
skin/blemishes by selecting an opaque cosmetic coating that is exactly the same colour as the
surrounding skin and subsequently applying that coating to the skin discoloration/blemish to
hide or mask the discoloration/blemish resulted in an unnatural and overly-made up, almost
plasticky, look. Rather than simply trying to hide the discoloration/blemish, the translucent
coating can have an additive or complementary effect with the underlying
discoloration/blemish such that the discoloration/blemish, when coated, has a more natural
appearance whilst still matching the appearance of the surrounding skin.
According to a fifth aspect of the present invention, there is provided a sunscreen
composition for skin, said composition comprising resin, flexibilizer and sunscreen agent,
wherein upon application to skin, said composition forms a waterproof flexible film having a
defined sun protection factor (SPF) value.
Any suitable type of sunscreen agent may be used. The composition may include one
or more sunscreen agents. Suitable sunscreen agents include titanium dioxide and zinc oxide.
Preferably, the composition includes zinc oxide. If a clear sunscreen is desired, the zinc oxide
may have a particle size of about 5-100 tun, and more preferably a particle size of about 20-40
tun. If a white opaque sunscreen is desired, the zinc oxide may have a larger particle size.
The composition may have any defined SPF value, depending on its intended use. Preferably,
the SPF value is at least 15 and more preferably at least 30. The composition may be applied to
the skin in layers so as to exceed an SPF value of 30. A multilayer film may provide an SPF
value of over 1000.

In a preferred embodiment the at least one sunscreen agent is present in an amount of
about 10 to 60 % w/w sunscreen agent.
Preferably, the sunscreen film is durable in that it need not be reapplied for at least 1
to 3 days and up to about five days.
The sunscreen composition may further include a pigment and/or dye for coating
discoloured skin or skin blemishes, or for producing an opaque film. Individuals suffering
from xeroderma pigmentosum may benefit from a long-lasting opaque sunscreen having a high
SPF value. Such individuals may benefit from a multilayer film, whether the films are of the
same composition or of different compositions.
Preferably, the resin is shellac, the alcohol is denatured ethanol, the oil is castor oil (7-
20% w/w) or a mixture of castor oil (7-15% w/w) and rosehip oil (0.1-5% w/w), the cellulosic
preparation is ethyl cellulose, and the sunscreen agent is zinc oxide having a particle size of
between about 5-100 nm.
Preferably, the preferred form further comprises about 0.5-1% w/w preservative, such
as BHT.
Preferably, the preferred form further comprises about 0.5-5% w/w vitamin E acetate.
According to a sixth aspect of the present invention, there is provided a therapeutic
composition for skin, said composition comprising resin, flexibilizer and at least one
therapeutic agent, wherein upon application to skin, said composition forms a waterproof
therapeutic flexible film.
According to a seventh aspect of the present invention, there is provided a method for
prevent or treating a disorder of the skin, said method comprising the step of applying to the
skin a composition comprising resin, flexibilizer and at least one therapeutic agent, wherein
upon application to skin, said composition forms a waterproof therapeutic flexible film.
According to an eighth aspect of the present invention, there is provided the use of a
composition in the preparation of a medicament for the prevention or treatment of a skin
disorder, said composition comprising resin, flexibilizer and at least one therapeutic agent,
wherein said composition forms a waterproof therapeutic flexible film when applied to skin.
Any suitable type of therapeutic agent may be used. The composition may include one or more
therapeutic agents. A suitable therapeutic agent may be an antimicrobial such as a bactericide
or fungicide. Another suitable therapeutic agent may promote wound healing or have anti-

inflammatory properties. Yet another suitable therapeutic agent may be a steroid for treating
eczema or dermatitis. Such therapeutic agents are well known in the art. Examples of suitable
therapeutic agents include vitamins, such as vitamin E, and rosehip oil. Examples of suitable
growth factors are described, for example, in the specification published as WO92/09301 to
the American National Red Cross.
The therapeutic composition may include a pigment and/or dye for coating
discoloured skin or skin blemishes and/or a sunscreen agent.
As mentioned above, each of the above compositions may be formulated for
application to the skin, for example, as a paste, cream, gel, liquid or aerosol. The composition
may be applied by way of a sponge, brush or spray. The colour, strength, flexibility, plasticity,
stability, opacity, viscosity may be readily optimised by adjusting the quantity of each
ingredient of the composition. The same coating composition or different coating compositions
may be applied to the skin in two or more layers, so as to achieve an optimal effect.
The term "comprise" and variants thereof such as "comprising" and "comprised" are
used herein to denote the inclusion of a stated integer or integers, unless in the context of usage
an exclusive interpretation of a term is required. Preferred embodiments of the present
invention will now be described by way of example with reference to the accompanying
figures.
Brief Description of the Drawings
Figure 1 shows a patient having a port wine stain on her arm;
Figure 2 shows the patient of Figure 1 treated with a coloured film forming coating
composition according to an embodiment of the present invention;
Figure 3 is a plot of percentage transmittance versus wavelength for a coloured film
forming coating/sunscreen composition, according to an embodiment of the present invention;
Figure 4 is a plot of percentage transmittance versus wavelength for a sunscreen
composition, according to an embodiment of the present invention; and
Figures 5 to 8 are plots of percentage transmittance versus wavelength for a coloured
film forming coating/sunscreen composition, according to an embodiment of the present
invention.

Detailed Description of the Embodiments
Example 1- Preparation of a Coloured Film Forming Coating Composition
and Use Thereof for Coating a Skin Blemish
This example describes the preparation of a coloured coating composition and its use
in coating a skin blemish such that the blemish has the appearance of normal skin surrounding
the blemish. The composition is particularly useful for coating birthmarks, moles, basal cell
carcinomas, pigment-related disorders, scars, burns, acne, veins, tattoos, eczema, dermatitis
and bruising. The composition can be specifically colour tailored to the needs of an individual.
In order to formulate an appropriate coloured coating composition for coating a skin
blemish, several readings of colour (hue, chroma and lightness) were taken from the skin
blemish and normal skin surrounding the skin blemish using a spectrophotometer, the
procedure for which is described in detail in the applicant's co-pending International Patent
Application entitled "A Colour Compensating System". Colour readings were taken from the
darkest region of the skin blemish and averaged. Colour readings were also taken from normal
skin surrounding the skin blemish and averaged.
A computer database was then interrogated. The computer database contained
information relating to the colour properties of the blemish and the colour properties of the
skin, as well as information relating to the appropriate colour properties of the coating
composition to apply to the blemish such that the coated blemish exhibits the colour of the
surrounding skin. The preferred coating compositions have a degree of translucency such that
the colour of the coated skin blemish comprises the additive affects of the colour of the coating
and the underlying colour of the blemish.
The computer database may be used to select the coating composition. Alternatively,
the computer database may provide information as to the desirable colour properties of the
coating composition required to obtain the appropriate compensatory colour properties and this
information may then be used to provide instructions to the user as to an appropriate coating
composition to be prepared to obtain the desired compensatory colour properties.
Once the desired coloured coating composition had been determined, that coating
composition was made up from its basic ingredients.

A. Preparation of Primary Pigment and Dye Dispersions
A primary dispersion was made for each pigment and dye to be used in the coloured
composition.
Primary dispersions were prepared using one or more of the following pigments and
dyes:
• Natural or synthetic iron oxides, black, red, yellow, brown, blended in various
ratios.
• Rutile titanium dioxide (micronised).
• Zinc oxide (micronised).
• Ultramarine blue (micronised).
• Mixed metal oxide (cobalt) blue, black, turquoise, green.
• Bon arymadide red pigments.
• Bon red (calcium).
• Rubine toners.
• Arylamide yellows.
• Transparent iron oxide pigments.
• Phthalocyanine blues.
• Dioxazine violets.
• Pearlescent pigments in various colours, including white, copper, bronze.
• Solvent dyes red, orange, yellow, blue, violet, brown, black.
Such pigments and dyes (as well as other suitable pigments and dyes) are available
from Redox Chemicals, Polyimpex, Avlo Australia, Clariant Australia, Shepherd International,
Merk Australia, Ravenswood Australia, HCA Colours, Degussa Australia, Quantum
Chemicals, Multichem, GCI Chemicals Australia, Orica Australia, Tradechem, Johnson and
Mathey, Elementis, Bayer Chemicals Pty Ltd, BASF Australia, DIC International, APS
Australia, and OMYA Southern.
Each pigment or dye 5-60% w/w was individually mixed to balance with castor oil (to
100% w/w) using a high-speed disperser for approximately 20 minutes, until the pigment or
dye was fully wetted.

Each resulting liquid/paste was processed through a bead mill or triple roll mill until a
dispersion was achieved of less than 5 micron particle size. Particle size and agglomeration
parameters were checked, e.g. using a Hegman guage. Each primary pigment and dye
dispersion was then stored in a respective container.
B. Preparation of a Film Forming Composition
Shellac in both solid and liquid form is available from Redox Chemicals, Avlo
Australia as well as from Quantum Chemicals. There are many forms of natural shellac
available which vary greatly in colour from dark amber to blonde honey colour. A bleached
version was used to give minimum coloration to the coloured composition.
De-waxed (blonde) shellac flakes 28% w/w were added slowly to ethanol 55 % w/w
and stirred until all of the shellac had dissolved. The solution was strained through a 10 micron
filter cloth and then the following ingredients were added: ethyl cellulose 4% w/w; castor oil
4% w/w; inorganic thixotrope 4% w/w; preservatives 2% w/w and ethanol to 100% w/w.
A suitable preservative may include, for example, one or more of the following:
butylated hydroxytoluene, butylated hydroxyanisole, hydroquinone and methylhydroquinone.
Such preservatives may be obtained from Multichem, Redox Chemicals, APS Australia,
Quantum Chemicals and Johnson Mathey.
The solution was stirred with gentle heating until all of the solids had dissolved and
then strained through a 10 micron filter cloth. The solution was then stored in a container.
C. Preparation of a Blend of Primary Pigment and Dye Dispersions
From the computer/spectrophotometer prediction, select primary pigment and dye
dispersions (from part A.) were blended together using a high-speed mixer until homogenous -
eg. white ("vehicle") 86.16% w/w, black 03.77% w/w, red 0.58% w/w, yellow ochre 10.88%
w/w. A white base (vehicle) was usually prepared from a dispersion of zinc oxide or titanium
dioxide.
D. Preparation of a Coloured Film Forming Coating Composition
A final coloured film forming coating composition was then prepared as follows:
blend of pigment and dye dispersions (from part C.) 12% w/w
film forming composition (from part B.) 88% w/w
The coloured coating composition was mixed vigorously and then applied to skin
using brushing, sponging, or airbrushing.

The composition may be readily applied to large skin areas using an airbrush gun. For
airbrushing, the final coloured film forming composition 30% volume by volume (v/v) may be
diluted in ethanol 70% v/v. The composition is preferably applied to the skin in a cross-
hatching manner.
For brushing or sponging, the coloured film forming composition may be used
without dilution. A sponge having pores of an appropriate size can produce a stippled effect on
the skin. The skin is usually cleaned with soapy water (to remove oils and chemical residues)
prior to applying the composition.
Figure 1 shows a patient 1 having a port wine stain 2 extending over her arm 3, neck 4
and chest 5. Figure 2 shows the same patient 1 but with the port wine stain 2 coated with a
coloured composition prepared in accordance with Example 1.
Example 2 - Preparation of a Coloured Film Forming Coating Composition
and Use Thereof for Coating a Skin Blemish
This example describes the preparation of another preferred coloured coating
composition and its use in coating a skin blemish such that the blemish has the appearance of
normal skin surrounding the blemish.
A. Preparation of Primary Pigment and Dye Dispersions
A primary dispersion was made for each pigment and dye to be used in the coloured
composition. Primary dispersions were prepared as described in part A. of Example 1 except
that the quantity of each pigment or dye varied and was balanced to 100% w/w using triple
refined castor oil.
B. Preparation of a Film Forming Composition
A film forming composition was prepared as described in part B. of Example 1 except
that the composition comprised:
de-waxed (blonde) shellac flakes 10.37% w/w;
ethyl cellulose 6.10% w/w;
castor oil 13.34% w/w;
rosehip oil 0.99% w/w;
BHT 1.23% w/w;

fumed silica 4.17% w/w; and
ethanol 63.80% w/w.
C. Preparation of a Blend of Primary Pigment and Dye Dispersions
As described in part C. of Example 1, select primary pigment and dye dispersions
(from part A.) were blended together.
D. Preparation of a Coloured Film Forming Coating Composition
A final coloured film forming coating composition was then prepared as follows:
blend of pigment and dye dispersions (from part C.) 12% w/w
film forming composition (from part B.) 88% w/w
The coloured coating composition was mixed and then applied to skin using brushing,
sponging, or airbrushing. For airbrushing, the final coloured film forming composition 30%
volume by volume (v/v) may be diluted in ethanol 70% v/v.
Shellac, ethyl cellulose, castor oil, fumed silica and ethanol are the minimum
ingredients required to form the film.
If a matte effect is desired, a fixing powder may be further applied to the coated skin.
The fixing powder may be initially applied by sponge immediately after application of the
composition and then reapplied after washing the skin. The fixing powder comprised:
92.99% w/w talc;
4.65% w/w zinc stearate;
1.43% w/w silicone oil; and
0.93 % w/w Unigerm G2™ (a mixture of methylparaben, ethylparaben, propylene
glycol and mydazolidinyl urea).
Example 3 - Preparation of a Film Forming Sunscreen Composition
and the Use Thereof
This example describes the preparation of a sunscreen composition and the use
thereof. The sunscreen composition may protect individuals from premature ageing of skin,
skin cancer and other harmful effects of solar radiation. Since the sunscreen film is long-
lasting and has a high SPF value, it will be of particular use to those who are exposed to
sunlight for long periods of time (e.g. sportsmen).

A. Preparation of a Film Forming Composition
De-waxed (blonde) shellac flakes 28% w/w were added slowly to ethanol 55% w/w
and stirred until all of the shellac had dissolved. The solution was strained through a 10 micron
filter cloth and then the following ingredients were added: ethyl cellulose 4% w/w; castor oil
4% w/w; inorganic thixotrope 4% w/w; preservatives 2% w/w and ethanol to 100% w/w. The
solution was stirred with gentle heating until all of the solids had dissolved and then strained
through a 10 micron filter cloth. The solution was stored in a container.
B. Preparation of a Nano Zinc Oxide Dispersion
Inorganic zinc oxide was milled to a nano scale, of less then 100nm particle size.
High energy milling in dry form was used to induce chemical reactions during ball-powder
collisions to form nano particles in a solid-state matrix.
Agglomeration was minimized by ensuring that the particles were encapsulated on
formation by a solid diluent phase (typically sodium chloride). The solid diluent phase was
removed by a basic washing technique. This process formed equiaxed nano particles with a
very narrow size distribution and very low levels of agglomeration.
The solid diluent phase allowed the particles to be heat treated without any
agglomeration occurring. The heat treatment step ensured the product was completely reacted,
removed all residual chemicals and stabilized the surfaces of the particles. The stabilized
surfaces assisted in decreasing the reactivity of the particles, which aided in the subsequent
dispersion in both aqueous and non-aqueous phases, and limited the generation of free radicals.
Zinc oxide becomes transparent when processed to nano particle size but still retains
its UV protection properties. Due to its high refractive indices, zinc oxide blocks UV by both
scattering and band gap absorption. A 20-40nm particle size was selected to provide broad
spectrum UVB and UVA protection with maximum transparency in excess of 80%.
Dry milled 20-40nm zinc oxide (40% w/w) was added slowly to the film forming
composition of part A. (60% w/w) and mixed for a minimum of 20 minutes until a
homogenous dispersion had been produced. The nano zinc oxide dispersion was then strained
through a 10 micron filter cloth and stored in a container.
C. Preparation of a Film Forming Sunscreen Composition
A final film-forming sunscreen composition was made up as follows and mixed
vigorously before application to the skin:

film forming composition (of part A.) 70% w/w
nano zinc oxide dispersion (of part B.) 30% w/w
The sunscreen composition was then applied using brushing, sponging, or airbrushing.
Example 4 - Sun Protection Factor Value of a Sunscreen Composition
Containing Micronised Zinc Oxide
A coloured coating composition was prepared in accordance with Example 1 and had
the colour blend: blue 0.60% w/w; red 0.53% w/w; yellow ochre 11.25% w/w; and white
(vehicle) 47.60% w/w. Since the vehicle comprised micronised zinc oxide, the coloured
coating composition also functioned as a sunscreen.
The composition was analysed using a Labsphere SPF Analyser with the following
parameters:
• substrate: MimSkin ® on quartz
• film thickness: 2mg/cm2
• number of scans: 10
• UVBAJVA cut off: 320 nm
The results are summarised in the following tables:
Brush application - single film layer

The final table shows that multilayering the film on skin (four layers) is likely to
provide a much higher SPF value, in this case being 1216.65. Figure 3 is a plot of percentage
transmittance versus wavelength for the composition when applied as four layers, and indicates
that the composition can provide broad UV protection.

Example 5 - Preparation of a Film Forming Therapeutic Sunscreen Composition
This example describes the preparation of a preferred therapeutic sunscreen
composition.
A film forming composition was prepared as described in parts A., B. and C. of
Example 3 except that the final composition comprised:
de-waxed (blonde) shellac flakes 12.96% w/w;
ethyl cellulose 7.79% w/w;
castor oil 1.14% w/w;
rosehip oil 0.50% w/w;
BHT 1.00% w/w;
vitamin E acetate 0.50% w/w;
nano zinc oxide (Zinclear™) 34.40%; and
ethanol 41.44% w/w.
Shellac, ethyl cellulose, castor oil, nano zinc oxide and ethanol are the minimum
ingredients required to form the film.
The composition contains the therapeutic agent vitamin E acetate. This agent is an
antioxidant and can decrease the effects of psoriasis, erythema and scaring from wounds. If
desired, other therapeutic agents (eg. growth factors, steroids) may be used in the composition.
Example 6 - Sun Protection Factor Value of a Sunscreen Composition
Containing Nano Zinc Oxide
The therapeutic composition of Example 5 was analysed using a Labsphere SPF
Analyser with the following parameters:
• substrate: MimSkin ® on quartz
• rub-in method
• film thickness: 2mg/cm2
• number of scans: 10
• UVB/UVA cut off: 320 nm
The results are summarised in the following tables:
Pre photodegradation

Figure 4 is a plot of percentage transmittance versus wavelength for the composition
when applied as a single layer. As for the composition tested in Example 4, multilayering the
film on skin (four layers) provided a much higher (and more than additive) SPF value, and
provided broad UV protection (results not shown).
Example 7 - Sun Protection Factor Value of a Coloured Sunscreen Composition
A coloured coating composition was prepared in accordance with Example 2.
The following primary dispersions were prepared (to 100% w/w balance with castor
oil):
black iron oxide (Elementis) 25% w/w
rubine bright red (Polyimpex) 20% w/w
white (Tronox® CR-828 titanium dioxide) 50% w/w
yellow ochre 40% w/w
The following primary dispersion quantities were mixed with 44g of the film forming
composition described in part B. of Example 2:0.03g black iron oxide; 0.07g rubine bright
red; 4.13g white; and 1.48g yellow ochre.
Since the composition contained titanium dioxide, the coloured coating composition
could also function as a sunscreen.
The composition, applied in 1 to 4 layers, was analysed using a Labsphere SPF
Analyser with the following parameters:
• substrate: MimSkin ® on quartz
• rub-in method
• film thickness: 2mg/cm2
• number of scans: 10
• UVB/UVA cut off: 320 nm
The results are summarised in the following tables:
Spray application - single film layer

The final table shows that multilayering the film on skin (four layers) is likely to
provide a much higher SPF value, in this case being 115.21. Figures 5-8 are plots of
percentage transmittance versus wavelength for the composition when applied as one to four
layers, respectively, and indicate that the composition can provide broad UV protection.
The coating compositions as exemplified herein have one or more of the following
advantages:
• they are flexible and durable on the skin (typically lasting between 1 to 5 days);
• they may be multilayered to provide a superior effect;
• they are waterproof and sweat proof;
• they remain intact even when immersed in hot water;
• they bond to the skin when immersed in saltwater;
• they remain intact even if clothing or a shaver is scraped over the film
• they help keep the skin sterile;
• they do not cause skin blemishes (pimples, breakouts);
• they are gentle to the skin; and • they are easy to apply to the skin.

Whilst the above has been given by way of illustrative example of the invention, many
modifications and variations may be made thereto by persons skilled in the art without
departing from the broad scope and ambit of the invention as herein set forth.

WE CLAIM:
1. A coating composition suitable for use on skin, said composition
comprising:
(a) 5-30% w/w resin;
(b) 50-80% w/w alcohol;
(c) 7-42.5% w/w oil;
(d) 2-10% w/w cellulosic preparation; and
(e) 0.5-10% w/w inorganic thickener,
wherein the ratio of resin to oil to cellulosic preparation ranges from
0.5:0.7:1 to 15:21.25:1.
2. The coating composition as claimed in claim 1, wherein the resin is a
natural or synthetic resin.
3. The coating composition as claimed in claim 1, either of claims 1 or 2,
wherein the oil is selected from castor oil, pine oil, eucalyptus oil, ti-tree
oil, rosehip oil, soya bean oil or a mixture thereof.
4. The coating composition as claimed in any one of claims 1 to 3,
wherein the inorganic thickener is selected from compounds such as
silicon dioxide (fumed silica), castor oil derivatives, quaternium
ammonium compound of bentonite, zinc stearate, nano zinc oxide,
inorganic thixotrope or modified clays.
5. The coating composition as claimed in the preceding claims, wherein
the resin is shellac, the alcohol is ethanol, the oil is a mixture of 7 to

42.4% w/w castor oil and 0.1 to 5% w/w rosehip oil, the cellulosic
preparation is ethyl cellulose, and the inorganic thickener is silicon
dioxide.
6. The coating composition as claimed in any one of claims 1 to 5,
wherein the coating composition further comprises one or more
pigments, or one or more dyes, or one or more pigments and one or more
dyes.
7. The coating composition as claimed in claim 6, wherein the coating
composition comprises 0.01 to 10% w/w pigment, or dye or pigment and
dye.
8. A coating composition suitable for use on skin comprising 30% volume
by volume (v/v) of the composition of claim 7 and 70% v/v ethanol.
9. The coating composition as claimed in any one of claims 1 to 7,
wherein the coating composition further comprises one or more
sunscreen agents.
10. The coating composition as claimed in claim 9, wherein the coating
composition comprises 10 to 60% w/w sunscreen agent.
11. The coating composition as claimed in claim 10, wherein the
sunscreen agent comprises zinc oxide.

12. The coating composition as claimed in either of claims 10 or 11,
wherein the resin is shellac, the alcohol is ethanol, the oil is a mixture of
7 to 15% w/w castor oil and 0.1 to 5% w/w rosehip oil, the cellulosic
preparation is ethyl cellulose, and the sunscreen agent is zinc oxide
having a particle size of between 5 to 100 nm.
13. The coating composition as claimed in any one of claims 1 to 7 or 9
to 12, wherein the coating composition further comprises one or more
therapeutic agents.
14. The coating composition as claimed in claim 13, wherein the
therapeutic agent is selected from antimicrobial agents such as
bactericide, fungicide; wound healing agents, anti-inflammatory agents,
steroids.
15. The coating composition as claimed in claim 13, wherein the
therapeutic agent comprises 0.5 to 5% w/w vitamin E acetate.
16. The coating composition as claimed in claim 5 in the formation of a
waterproof flexible coloured film for coating a skin discoloration or skin
blemish,, said coating composition comprising an effective amount of one
or more pigments, or one or more dyes, or one or more pigments and one
or more dyes.

17. The coating composition as claimed in claim 16, wherein said
coating composition further comprises a sunscreen agent or a
therapeutic agent or a sunscreen agent and a therapeutic agent.
18. The coating composition as claimed in either of claims 16 or 17,
wherein the skin discoloration or blemish is selected from the group
consisting of a birthmark, a mole, a basal cell carcinoma, vitiligo, a scar,
a burn, pigmentation, acne, a vein, tattoo, eczema, dermatitis and
bruising.
19. The coating composition as claimed in any one of claims 16 to 18
wherein the coating composition is formulated to enable the use of a
fixing powder on the coated skin discoloration or blemish.
20. The coating composition as claimed in claim 19, wherein the fixing powder comprises:

(a) 93.0% w/w talc;
(b) 4.7% w/w zinc stearate;
(c) 1.4% w/w silicone oil; and
(d) 0.9% w/w preservative.

21. The coating composition as claimed in any one of claims 16 to 20,
is formulated as a paste.
22. The coating composition as claimed in any one of claims 16 to 21,
wherein the coating composition of claim 6 is formulated for dilution in
ethanol prior to use to produce a composition having 30% volume by
volume (v/v) of the coating composition and 70% v/v ethanol and
wherein the diluted coated composition is suitable for administration to
the skin by spraying.

23. The coating composition as claimed in any one of claims 9 to 13 in
the preparation of a waterproof flexible film, said coating composition
comprising an effective amount of one or more therapeutic agents, or one
or more sunscreen agents, or one or more therapeutic agents and one or
more sunscreen agents for the prevention or treatment of a disorder of
the skin wherein, upon application to skin, said coating composition
forms a waterproof flexible film.
24. The coating composition as claimed in claim 23, wherein said
disorder of the skin is xeroderma pigmentosum.

ABSTRACT

A composition for coating skin comprising shellac, ethanol, castor oil,ethyl cellulose and
fumed silica or nano zinc oxide, wherein the composition forms a long lasting waterproof
flexible film on skin. The composition may include different ingredients for different
applications. In one embodiment, the composition includes pigment and/or dye and may
be used to coat a skin blemish such that the skin blemish blends in with the surrounding
skin. In another embodiment, the composition includes a sunscreen agent and may be
used as a sunscreen. In yet another embodiment, the composition includes a therapeutic
agent for treating a disorder of the skin.

SKIN COATING COMPOSITIONS AND USES THEREOF

Documents:

Inventors:

PCT Conventions: