EMULSIFIED HYDRATED STICK PRODUCT

Abstract: A solid hyrdated stick for topical applica­ tion containing emulsified water soluble ingredients and volatile emollients. The stick is a solid emulsion comprising by weight from 15% to 40% of a cyclic silicone, 2% to 15% of an oil, 2% to 20% of a wax, 2% to 7% of polyethylene glycol sorbitan beeswax, 10% to 40% water, and 0.1% to 40% of a cosmetically acceptable functional ingredient. The polyethylene glycol sorbitan beeswax acts as an emulsifier and contributes to the rigidity of the stick, while the silicone serves as an emollient to impart a smooth, buttery feel when the composition is applied to the skin.

Description: This invention relates to a solid emulsified stick composition for topical application. Historically, solid stick products have been used in the cosmetic and pharmaceutical industries for their convenience and ease of application over creams or lotions. The conventional solid stick is anhydrous and is composed largely of oils and waxes. The waxes are needed to achieve a rigid structure to permit the stick to stand upright and the oils are required to plasticize the waxes to allow mass release to the skin. Coloring agents or other active ingredients are incorporated in the oil and wax base. Anhydrous sticks have the disadvantage of applying large quantities of oil and wax to the skin, thus producing a heavy lardy feel to the skin. This is a negative feeling but one previously thought necessary because of the waxy ingredients needed to produce a rigid stick. Recently, cyclic or volatile silicones have been utilized as emollients in cosmetic or pharmaceutical products. The silicones have been used in place of the conventional plasticizing oils and after application to the skin, the silicone evaporates leaving a wax/color or active ingredient matrix on the skin. The evaporative effect is less occlusive than the conventional oil/wax matrix and thus is more comfortable to the user. While the use of silicones as an emollient represents an improvement over earlier technology, the final feel on the skin is still heavy and waxy after the volatile silicone evaporates from the skin. EP-A-0 117 070 discloses solid stick compositions comprising a long chain fatty alcohol having from about 8 to 18 carbon atoms in the chain, volatile silicone and C20 or longer chain alcohols at levels of from about 1% to about 3% of the total long chain fatty alcohol present in the compositions. Said solid sticks have improved strength and hardness without undue brittleness. The invention is directed to a solid stick for topical application that contains emulsified water soluble ingredients and volatile emollients. The stick is a solid emulsion comprising by weight from 15% to 40% of a volatile cyclic silicone, 2% to 15% of oils, 2% to 20% of waxes, 2% to 7% of polyethylene glycol sorbitan beeswax, 10% to 40% water and from 0.1% to 40% of a cosmetically acceptable functional ingredient. The polyethylene glycol sorbitan beeswax acts to emulsify the oils, waxes and emollient in the water base and also contributes to the rigidity of the stick. The cyclic silicone serves as an emollient and evaporates along with the water when the composition is applied to the skin to provide a smooth buttery feel, as opposed to a heavy, waxy feel for the conventional anhydrous stick. As the water soluble functional ingredients, such as colorants or active ingredients, are delivered in solution to the skin, they are applied in a diluted non-irritating form ready to perform their function when delivered. The stick composition of the invention can be used to provide a wide variety of cosmetic and pharmaceutical products. One preferred embodiment of the present invention is directed to a solid sticK composition for topical application which contains emulsified water soluble ingredients and volatile emollients. In general, the stick has the following composition in weight percent. Volatile cyclic silicone 15 - 40% Oils 2 - 15% Waxes 2 - 20% Polyethylene glycol sorbitan beeswax 2 - 7% Water 10 - 40% Functional ingredients 0.1 - 40% The volatile silicone is a liquid at room temperature and preferably takes the form of a siloxane composed primarily of two cyclic components: D4 cyclomethicone and D₅ cyclomethicone. The D5 component represents the majority with the D4 being a minor constitutent. Chemically D₄ cyclomethicone may be symbolically written as: and D₅ cyclomethicone may be symbolically written as: The silicone acts as an emollient during application to the skin, leaving an emulsified matrix of waxes and colorants or active ingredients on the skin. Since the waxes are emulsified, and both the silicone and the water evaporate after application, a smooth light buttery feel is imparted to the skin as opposed to the heavy, waxy or lardy feel associated with a conventional anhydrous stick. The oils can take the form of any oils normally employed in cosmetic or pharmaceutical products and may be selected from mineral oil, corn oil, soyabean oil, apricot kernel oil, coconut oil, clove oil, lemon oil, olive oil, sunflower seed oil, jojoba oil, sesame oil, peanut oil, safflower oil, grapeseed oil, castor oil, cotten seed oil, avocado oil, almond oil, wheat germ oil, oil of orchids and rice bran oil. The waxes are common types used in cosmetic and pharmaceutical products such as ceresin wax, castor wax, carnauba wax, paraffin wax, candelilla wax, bees wax, ozokerite, microcrystalline wax, bayberry wax, Japan wax, rice bran wax, spermaceti wax. In addition, fatty acid alcohols containing from 12 to 22 carbon atoms, such as stearyl alcohol, lauryl alcohol, and the like, can also be used as the wax component. The polyethylene glycol sorbitan beeswax is an ethoxylated sorbitol derivative of beeswax containing various moles of ethylene oxide. For example, Atlas G-1726 (ICI Americas Inc.) is an ethoxylated sorbitol derivative of beeswax with an average of 20 moles of ethylene oxide. Other derivatives such as those containing an average of 6 or 8 moles of ethylene oxide can also be utilized. The term "functional ingredients" as used in the description and claims is intended to cover active ingredients, colorants and other additives to the composition. The functional ingredients can take the form of colorants such as guanine crystals, carmine, bismuth oxychloride, mica, iron oxides, titanium dioxide, manganese violet, ultramarine blue, ultramarine pink, ultramarine violet, ultramarine rose, chromium hydroxide green, chromium oxide green, bronze powder, aluminum powder, ferric ferrocyanide, ferric ammonium ferrocyanide, and D & C organic pigments; antiperspirants such as aluminum chlorohydrate, or aluminum zirconium tetrachlorohydroxglycine; bacteriocides such as mercurochrome; skin lightening agents such as hydroquinone; auxilliary emulsifiers or texturizers such as methyl glucose dioleate; suspending agents such as magnesium aluminum silicate; preservatives such as methyl paraben; and other functional materials commonly used in topical products such as panthenol, lanolin, collagen, aloe vera, honey, ginseng extract, sodium thioglycolate, fragrances, 2-pyrrolidone-5-carboxylic acid, vitamins, chamomile extract, witch hazel extract, lemon juice, comfrey extract, rosehips, mint extract, hayflower extract, glycerin, 1,3 butylene glycol, propylene glycol, sodium lauryl sulfoacetate and polyamino sugar condensate (and) urea. To prepare the stick composition of the invention, the silicone, oils, waxes and the emulsifier are heated to a temperature generally in the range of 60° to 80°C to provide a liquid mixture. Water, along with the water soluble functional ingredients, are admixed with the liquid mixture and the combination is agitated or homogenized at a temperature of 60° to 80°C to provide the emulsion. The emulsion is then poured by gravity either directly into the final package to form the solidified stick product, or into molds to form sticks which are subsequently transferred to the final package. The stick composition of the invention contains a substantially lesser amount of waxes and oils than a conventional anhydrous stick. The volatile silicone acts as an emollient during application leaving an emulsified matrix of waxes and oils along with functional ingredients on the skin. After application, the silicone as well as the water will evaporate from the skin and the evaporative effect imparts a smooth, light feel to the skin as opposed to the heavy, waxy or lardy feel associated with the conventional anhydrous stick. As a further advantage, the colors have a deeper or more intensive affect on the skin since there is a lesser wax matrix to interfere with their perception. As large quantities of oil are not required to affect mass release to the skin, the product will wear longer on the skin since oils present cause creasing of color from the skin. A further advantage is that the water soluble functional ingredients are delivered in solution to the skin. In addition to achieving faster results on the skin, the functional ingredients are less irritating since they are already diluted in solution and do not have to be solublized by the skins ingredients. The following examples illustrate the solid stick composition of the invention. I. Blusher Stick Cyclomethicone 23.90% Stearyl alcohol 16.00 PEG-20 sorbitan beeswax 2.00 Sesame oil 2.00 Methyl glucose dioleate 1.00 1% Aq. dispersion magnesium aluminum silicate 30.00 Color blend 25.00 100.00% II. Cosmetic Cyclomethicone 34.55% Stearyl alcohol 18.67 PEG-20 sorbitan beeswax 2.67 Sesame Oil 2.67 Methyl glucose dioleate 1.34 Deionized water 33.60 5-hydroxy-6-methyl-3,4-pyridinedimethanol hydrochloride 5.00 (2,5-dioxo-4-imidazolidinyl) urea .50 100.00% III. Sunscreen Stick: Octyl dimethyl PABA 8.00% Cyclomethicone 35.65 Stearyl alcohol 18.67 PEG-20 sorbitan beeswax 2.67 Sesame oil 2.67 Methyl glucose dioleate 1.34 Deionized water 30.00 100.00% IV. Antiperspirant Stick: Magnesium aluminum silicate 5% dispersion Aq. 36.50% Aluminum chlorohydrate 18.00 Cyclomethicone 21.50 Stearyl alcohol 18.00 PEG-20 sorbitan beeswax 3.00 Sesame oil 2.00 Methyl glucose dioleate 1.00 100.00% V. Sunscreen with aloe stick: Octyl dimethyl PABA 8.00% Cyclomethicone 36.15 Stearyl alcohol 18.67 PEG-20 sorbitan beeswax 2.67 Sesame oil 2.67 Methyl glucose dioleate 1.34 Deionized water 24.50 Aloe 5.00 100.00% VI. Blusher Stick: Cyclomethicone 21.50 Stearyl alcohol 16.00 PEG-20 Sorbitan Beeswax 5.00 Sesame Oil 5.00 Methyl glucose dioleate 1.00 Propylparaben 0.20 1% Aq. dispersion magnesium aluminum silicate 26.00 Methylparaben 0.30 Color Blend 25.00 100.00% VII. Blusher Stick Cyclomethicone 24.50 Stearyl alcohol 14.00 PEG-20 Sorbitan beeswax 7.00 Sesame oil 7.00 Methyl glucose 1.00 Propylparaben 0.20 1% Aq. dispersion magnesium aluminum silicate 26.00 Methylparaben 0.30 Color blend 20.00 100.00%

Claims: A solid emulsified stick composition for topical application, comprising by weight from 15% to 40% of a cyclic volatile silicone, 2% to 15% of a cosmetically acceptable oil, 2% to 20% of a cosmetically acceptable wax, 2% to 7% of polyethylene glycol sorbitan beeswax, 10% to 40% water and 0.1% to 40% of a cosmetically acceptable functional ingredient. A stick composition according to claim 1, wherein said wax is a fatty acid alcohol containing from 12 to 22 carbon atoms. A stick composition according to claim 2, wherein said fatty alcohol is stearyl alcohol. A stick composition according to claim 1, 2 or 3, wherein said functional ingredient comprises a colorant. A stick composition according to claim 1, 2 or 3, wherein said functional ingredient comprises an antiperspirant. A stick compositions according to any of claims 1 to 5, wherein said silicone is cyclomethicone. A solid emulsified cosmetic stick, comprising by weight from 15% to 40% of a cyclic volatile silicone, 2% to 15% of a cosmetically acceptable oil, 2% to 20% of a cosmetically acceptable wax, 2% to 7% of polyethylene glycol sorbitan beeswax, 10% to 40% water, and 0.1% to 40% of a water soluble functional ingredient. The stick composition according to claim 7, wherein said functional ingredient comprises a colorant. A solid emulsified cosmetic stick, comprising by weight from 15% to 40% of a cyclomethicone, 2% to 15% of a cosmetic oil, 2% to 20% of a cosmetic wax, 2% to 7% of polyethylene glycol sorbitan beeswax, 10% to 40% water, and 0.1% to 40% of a cosmetic colorant.

Inventors: BERG, RICHARD D., CASPERSON, STEPHEN, MURPHY, JOHN H.
Applicants: KOLMAR LABORATORIES, INC.
Application year: 1988
Main classification: A61K7
IPC codes: A61Q15, A61K8, A61Q1, A61Q19