Cosmetic compositions having enhanced color stability

Abstract

The present invention is directed to personal care compositions containing resorcinols. Effective methods for improving the color stability of compositions containing resorcinols are desirable. It has been discovered that alkylresorcinols and retinoids combined with compatible oils and specific ratios of antioxidants provide improved color stability of resorcinols. Accordingly, the present invention relates to compositions containing a synergistic combination of butylated hydroxytoluene and dilauryl thiodipropionate with alkylresorcinols and retinoids.

Description

[Technical field]

[0001] The present invention is in the field of personal care compositions; in particular, in the field of skin benefit compositions. More particularly, the present invention relates to cosmetic compositions comprising oil-soluble alkylresorcinols and retinoids in combination with compatible oils and antioxidants to provide improved color stability of the composition. [Background technology]

[0002] The standard definition of ideal skin currently includes youthful, elastic skin with an even color distribution and smooth texture throughout. However, skin is subject to deterioration, for example, by chronoaging. Aging individuals increasingly exhibit facial fine lines, wrinkles, yellowing or sallowness, sagging, hyperpigmentation, age spots, and general signs of aging.

[0003] Skin care compositions containing retinoids, such as retinol, have become extremely prominent in recent years.Retinol, also known as vitamin A, and many of its ester derivatives, as well as members of the retinoid family (including, for example, retinyl propionate), when applied topically, are effective in reducing fine lines and wrinkles, smoothing the skin, and improving uneven skin tone, among other benefits.Despite the benefits of retinoids, the inclusion of retinoid compounds in cosmetic compositions often leads to difficulties with the stability of the composition.

[0004] In addition, many people turn to cosmetics with skin lightening properties, often for the desired even skin tone. There is a constant industry need for new cosmetic skin lightening agents with enhanced efficacy and stability.

[0005] Examples of skin lightening agents include niacinamide, hydroquinone, and kojic acid. Resorcinols, such as hexylresorcinol, provide further examples of skin lightening agents that can be used in topical applications to the skin.

[0006] Skin care compositions containing skin lightening agents such as hexylresorcinol have become extremely prominent in recent years. However, obtaining a color-stable cosmetic composition containing resorcinols is challenging. Color instability is important because consumers are sensitive to changes in the color appearance of the cosmetic compositions they use, especially if they believe that color changes are a clue to reduced chemical activity. The color instability of resorcinols is nonlinearly positively correlated with the chemical instability of resorcinols, but not proportionally. The color stability of compositions containing resorcinols tends to deteriorate in a shorter time than the chemical activity decreases. Trace amounts of chemical degradation of resorcinols due to external factors such as impurities in the case of formulation can cause significant color degradation. The problem of color instability of cosmetic compositions is exacerbated when both resorcinols and retinoid compounds are present in the composition. This is because the presence of both resorcinols and retinoid compounds results in greater color degradation compared to compositions in which each active is present independently. Thus, the color instability of cosmetic compositions containing both resorcinols and retinoids is more difficult to overcome.

[0007] The present inventors have therefore recognized a need to develop cosmetic compositions having improved color stability that contain both oil-soluble alkylresorcinols and retinoids and / or ester derivatives of the latter. Accordingly, the present invention is directed to cosmetic compositions having an oil-soluble alkylresorcinol in combination with (a) a retinoid, (b) an ester derivative of a retinoid, or (c) a mixture thereof, in addition to butylated hydroxytoluene, dilauryl thiodipropionate, and a compatible oil.

[0008] Additional Information Efforts to incorporate antioxidants into cosmetic compositions containing resorcinols and retinoids have been disclosed.

[0009] US Patent Publications US 2017281507, US 2017281508 and US 2017304178 disclose methods for reducing the symptoms of aging and / or improving the health of the human integument and useful compositions thereof comprising peptides having the respective amino acid sequences. These compositions may include, in the claimed invention, antioxidants, retinol and / or hexylresorcinol.

[0010] PCT application WO 2011 / 047420 describes polymers of 2-propenal, C 3-10 Topical antibacterial compositions containing an alkanediol and optionally containing resorcinol or retinol are reported.

[0011] US Patent Application Publication No. US 20160256368 reports a method of treating the skin to reduce the signs of aging and / or improve skin health by sequential, rotational or alternating topical application of at least two separate compositions that may optionally include antioxidants, retinols and resorcinols.

[0012] None of the above additional information describes the combination of antioxidants, which include butylated hydroxytoluene and dilauryl thiodipropionate, with resorcinol, retinoids and compatible oils to achieve the color stable cosmetic compositions used for anti-aging and whitening benefits disclosed in the claimed invention. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] US 2017281507 [Patent Document 2] US 2017281508 [Patent Document 3] US 2017304178 [Patent Document 4] WO 2011 / 047420 [Patent Document 5] US 20160256368 Summary of the Invention [Problem to be solved by the invention]

[0014] The inventors have discovered that, in addition to the use of a compatible oily carrier, specific ratios of antioxidants including BHT and dilauryl thiodipropionate enhance the color stability of compositions containing both a retinoid and an oil-soluble alkylresorcinol. [Means for solving the problem]

[0015] Accordingly, the present invention relates to an active antioxidant mixture of butylated hydroxytoluene and dilauryl thiodipropionate.

[0016] In a first aspect, the present invention is directed to an antioxidant mixture of butylated hydroxytoluene (BHT) and dilauryl thiodipropionate, further comprising an oil-soluble alkylresorcinol, a retinoid, or a mixture thereof with a compatible oil.

[0017] In a second aspect, the present invention is directed to a cosmetic composition comprising: (i) one or more oil-soluble 4-substituted alkylresorcinol compounds; (ii) one or more retinoids, retinoid ester derivatives or blends thereof; (iii) an active antioxidant mixture according to the first aspect of the present invention; (iv) a compatible oil; and (v) a cosmetically acceptable vehicle.

[0018] All other aspects of the present invention will become more readily apparent in light of the following detailed description and examples.

[0019] For the avoidance of doubt, the term "comprising" is intended not to be limited to the listed elements, but to encompass unspecified elements, whether of greater or lesser functional importance. Thus, the listed steps, elements or options need not be exhaustive. Whenever the expressions "including" or "having" are used, these terms are intended to be equivalent to "comprising" as defined above.

[0020] The term "skin" as used herein includes the skin of the face, neck, chest, back, arms, armpits, buttocks, hands, legs and scalp. An active, as used herein, is intended to include ingredients that improve and / or benefit facial or body characteristics (e.g., skin characteristics) after topical application, where the active can be, and preferably is, a cream, pump or aerosol spray, serum, lotion, balm, deodorant, gel or wash composition. In a particularly preferred embodiment, the composition of the present invention is a leave-on composition, and the active is a retinoid compound and an oil-soluble alkylresorcinol. Maintaining color stability, as used herein, refers to the L chromaticity measured by a Hunter Lab spectrophotometer. * , a * and b * "compatible" refers to a cosmetic composition having a ΔE of 10 or less based on the color difference of 10. In general, ΔE≦10 is acceptable, ΔE of 10-20 is negotiable, and ΔE>20 is unacceptable. As used herein, the term "compatible" refers to oils having a Hansen Total Solubility Parameter value in the range of 16-22. The Hansen Total Solubility Parameter is the sum of three Hansen parameters [i.e., δ t (defines the energy from dispersion forces between molecules), δ p (defines the energy from dipole-dipole intermolecular forces between molecules), and δ n (which defines the energy from hydrogen bonds between molecules).t Values ​​are obtained according to "CRC Handbook of Solubility Parameters and other Cohesion Parameters, Second Edition by Allan FM Barton".

[0021] Except in the examples, or where otherwise expressly indicated, all numbers indicating amounts of materials herein should be understood to be modified by the word "about." All amounts are based on the total weight of the composition unless otherwise specified. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The resorcinol compound contained in the cosmetic composition of the present invention is an oil-soluble alkylresorcinol. Illustrative non-limiting examples of oil-soluble 4-substituted alkylresorcinols include 4-hexylresorcinol, 4-phenylethylresorcinol, 4-cyclopentylresorcinol, 4-cyclohexylresorcinol, and mixtures thereof. The composition contains 0.001-10% by weight, preferably 0.01-5% by weight, and most preferably 0.01-1% by weight of the alkylresorcinol. In one embodiment of the present invention, the oil-soluble alkylresorcinol used in the present invention is 4-hexylresorcinol.

[0023] The compositions of the present invention comprise a retinoid, wherein the retinoid is selected from retinyl esters, retinol, retinal and retinoic acid, preferably selected from retinal or retinyl esters. Examples of retinyl esters suitable for use in the present invention include, but are not limited to, retinyl palmitate, retinyl formate, retinyl acetate, retinyl propionate, retinyl butyrate, retinyl valerate, retinyl isovalerate, retinyl hexanoate, retinyl heptanoate, retinyl octanoate, retinyl nonanoate, retinyl decanoate, retinyl undecanoate, retinyl taurate, retinyl tridecanoate, retinyl myristate, retinyl pentadecanoate, retinyl heptadecanoate, retinyl stearate, retinyl isostearate, retinyl nonadecanoate, retinyl arachidonate, retinyl behenate, retinyl linoleate, and retinyl oleate. Preferred esters for use in the present invention are selected from retinyl palmitate, retinyl acetate, retinyl propionate, and mixtures thereof. Retinyl linoleate and retinyl oleate are also preferred. Retinol or retinyl esters are used in the compositions of the present invention in an amount of 0.001-10%, preferably 0.01-1%, and most preferably 0.01-0.5%.

[0024] The use of a compatible oil in a composition containing an alkylresorcinol, a retinoid and an antioxidant has been unexpectedly found to contribute to improved color stability. Surprisingly, the Hansen total solubility parameters (δ t It has been found that oils having a δ ) value in the range of 16 to 22 (preferably 17 to 19) are most compatible and therefore suitable for use in such cosmetic compositions. Illustrative examples of suitable oils for use in the present invention include isopropyl myristate (δ t =17.5), caprylic / capric triglyceride (δ t =18.9) and isopropyl palmitate (δ t=17.2) The compatible oil is used in the composition of the present invention in an amount of 13 to 30%, preferably 14 to 28%, and most preferably 15 to 25%, based on the total weight of the composition.

[0025] Furthermore, it has been discovered that when a retinoid and an oil-soluble alkylresorcinol are combined in identified ratios with butylated hydroxytoluene (BHT) and dilauryl thiodipropionate (which is commercially available under the trademark "Tinogard DA" from the supplier BASF) to provide a cosmetically acceptable vehicle for the compositions of the present invention, enhanced color stability is unexpectedly observed as compared to a control of the same vehicle.

[0026] The total weight percentage of antioxidants included in the present invention is preferably 0.01-4 wt%, more preferably 0.02-3 wt%, and most preferably 0.05-2 wt%. The minimum total weight percentage of antioxidants included in the present invention is preferably 0.15 wt%, based on the total weight of the composition.

[0027] In one embodiment, in addition to cosmetic compositions containing resorcinols and retinoids, a weight ratio of 0.8:4.2 to 4.2:0.8 BHT to dilauryl thiodipropionate is preferred.

[0028] In another embodiment, a weight ratio of BHT to dilauryl thiodipropionate of 0.8:2.2 to 2.2:0.8 is more preferable.

[0029] In yet another embodiment, a weight ratio of BHT to dilauryl thiodipropionate of 0.8:1.2 to 1.2:0.8 is most preferred.

[0030] Color stability is confirmed using a LabScan XE instrument (Hunter Associates Laboratory, Inc. Reston, Virginia). The LabScan XE measures color data. Samples at various storage stages contained in vials or measurement cells are loaded into the LabScan XE measurement port. Color (a) and color (b) are measured according to the measurement procedure specified in the associated instrument menu and computer software. * , b * and L * ) is measured and calculated to obtain color change data (ΔE) values. For reference, a ΔE of about 3 is the threshold at which a color change from the original sample can be visually detected.

[0031] The cosmetic composition of the present invention can further comprise a cosmetically acceptable vehicle in addition to a compatible oil that acts as a diluent, dispersant or carrier for the skin benefit agent in the composition to facilitate its distribution when the composition is applied to the skin.The cosmetically acceptable vehicle can be aqueous, anhydrous or emulsion.Oil carrier in the presence of water and emulsifier as carrier forms an emulsion system.Preferably, the composition is aqueous or emulsion, particularly water-in-oil or oil-in-water emulsion, and preferentially oil-in-water emulsion.The cosmetic composition is usually in the form of a cream or lotion, but is not limited thereto.

[0032] In the most preferred embodiment, water is the carrier. The amount of water may range from 5 to 85%, more preferably 15 to 75%, and most preferably 30 to 70%, based on the total weight of the entire cosmetic composition, including all ranges contained therein. In addition to water, classes of suitable carriers include silicones, polyhydric alcohols, fatty acids, hydrocarbons, triglycerides, waxes, and thickeners.

[0033] Silicones can be classified into volatile and non-volatile types. The amount can range, for example, from 0.01 to 25% by weight, more preferably from 0.1 to 20% by weight, of the composition. The term "volatile" as used herein refers to a material that has a measurable vapor pressure at ambient temperature. Volatile silicone oils are preferably selected from cyclic (cyclomethicone) or linear polydimethylsiloxanes containing 3 to 9 (preferably 4 to 5) silicon atoms.

[0034] Non-volatile silicones useful in the composition include polyalkyl siloxanes, polyalkylaryl siloxanes, and polyether siloxane copolymers. Essentially non-volatile polyalkyl siloxanes useful in the present invention include, for example, polyalkyl siloxanes having a viscosity of about 5×10 at 25° C. -6 ~0.1m 2 and polydimethylsiloxanes having a viscosity of 100 / sec. Emulsifying and non-emulsifying silicone elastomers are also suitable for use in the cosmetic compositions of the present invention.

[0035] Conventional humectants, generally of the polyhydric alcohol type of material, can be used in the present invention. Typical polyhydric alcohols include glycerol (i.e., glycerine or glycerin), propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1,3-butylene glycol, isoprene glycol, 1,2,6-hexanetriol, ethoxylated glycerol, propoxylated glycerol, and mixtures thereof. Most preferred embodiments include glycerin, propylene glycol, or mixtures thereof. The amount of humectant used can range from 0.5 to 25% by weight, preferably 1 to 20% by weight, of the cosmetic composition.

[0036] Fatty acids may also be useful carriers. The term "fat" denotes carbon chain lengths ranging from 10 to 30 carbon atoms. Illustrative of this category are pelargonic acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, hydroxystearic acid, oleic acid, linoleic acid, ricinoleic acid, arachidic acid, behenic acid, erucic acid, and combinations thereof. When used, 0.01 to 5% by weight of fatty acids are present in the composition.

[0037] Waxes and wax esters such as beeswax, spermaceti, tribehenin wax, carnauba wax and candelilla wax are also suitable for use as carriers in the present invention. The amount of wax or wax ester used may range from 0.01 to 10%, preferably from 0.1 to 8% by weight of the composition.

[0038] Triglycerides are another group of materials useful as carriers. Illustrative non-limiting examples are sunflower seed oil, cottonseed oil, rapeseed oil, grape seed oil, soybean oil, castor oil, borage oil, olive oil, shea butter, jojoba oil and mixtures thereof. Monoglycerides and diglycerides may also be useful. Illustrative of these categories are glyceryl monostearate and glyceryl distearate. The amount of triglyceride may range from 0.01 to 10% by weight of the composition, preferably 0.1 to 8% by weight.

[0039] The carrier may contain one or more thickeners, preferably 0.05-10%, more preferably 0.1-5%, even more preferably 0.25-4% by weight of the composition. Useful thickeners may include polysaccharides, including starches, natural / synthetic gums, and cellulose derivatives. Suitable starches include tapioca starch, corn starch, potato starch, aluminum starch octenyl succinate, and sodium hydroxypropyl starch phosphate. Suitable gums include xanthan gum, sclerotium gum, pectin gum, karaya gum, gum arabic, agar gum, guar gum, carrageenan, alginates, and combinations thereof. Suitable cellulose derivatives include hydroxypropyl cellulose, hydroxypropyl methylcellulose, ethylcellulose, and sodium carboxymethylcellulose. Synthetic polymers that function as thickening agents are also suitable for use, where such synthetic polymers include polyacrylamides, carbopols, taurate copolymers and acrylate-based polymers.

[0040] An emulsifier is preferably present in the cosmetic composition of the present invention. Emulsifiers suitable for use in the present invention have an HLB of 2.5 to 17. When an oil continuous emulsion is desired, the HLB of the emulsifier used is 2.5 to 7.5, preferably 3 to 6.5, and most preferably 3 to 6, including all ranges therein. When a water continuous emulsion is desired, the HLB of the emulsifier used is 8 to 17, preferably 8.5 to 15, and most preferably 9 to 14, including all ranges therein.

[0041] The total concentration of the emulsifier can range from 0.1 to 20%, preferably 1 to 10%, and most preferably 1 to 8% by weight of the composition, including all ranges therein. The emulsifier can be selected from the group consisting of anionic actives, nonionic actives, cationic actives, and amphoteric actives. Particularly preferred nonionic actives are those containing: C condensed with about 2 to about 100 moles of ethylene oxide or propylene oxide per mole of hydrophobic material. 10 -C 20 fatty alcohol hydrophobe or fatty acid hydrophobe: C condensed with 2 to 20 moles of alkylene oxide 2 -C 10 Alkylphenols;Mono- and di-fatty acid esters of ethylene glycol;Fatty acid monoglycerides;Sorbitan, mono-C 8 -C 20 Fatty acids and di-C 8 -C 20 fatty acids; and polyoxyethylene sorbitan, and combinations thereof. Alkyl polyglycosides and sugar fatty amides (e.g., methyl gluconamide) are also suitable nonionic emulsifiers.

[0042] Preferred anionic emulsifiers include alkyl ether sulfates and sulfonates, alkyl sulfates and sulfonates, alkyl benzene sulfonates, alkyl and dialkyl sulfosuccinates, C 8 -C 20 Acyl isethionates, C 8 -C 20 These include alkyl ether phosphates, alkyl ether carboxylates, and combinations thereof.

[0043] Cationic emulsifiers that may be used include, for example, palmitamidopropyltrimonium chloride, distearyldimonium chloride, and mixtures thereof. Useful amphoteric emulsifiers include cocoamidopropyl betaine, C 12 -C 20Examples include trialkylbetaines, sodium lauroamphoacetate and sodium laurodiamphoetate or mixtures thereof.

[0044] Other generally preferred emulsifiers include glyceryl stearate, glycol stearate, stearamide AMP, PEG-100 stearate, as well as emulsifying / thickening additives such as hydroxyethyl acrylate / sodium acryloyldimethyltaurate copolymer / squalane and mixtures thereof.

[0045] Fragrances, actives, fixatives and abrasives can optionally be included in the cosmetic compositions of the present invention. Actives suitable for use in the present invention are intended to include, but are not limited to, opacifiers, colorants, moisturizers, emollients, occlusive agents, botanical extracts, optical agents, whitening agents, anti-inflammatory agents, anti-acne agents, sunscreens, light stabilizers, surfactants, wrinkle reducing agents, desquamation promoters, exfoliants, mixtures thereof, and the like. These materials may each range from 0.05 to 5% by weight, preferably 0.1 to 3% by weight.

[0046] Hydrocarbons can optionally be included in the cosmetic compositions of the present invention. Suitable hydrocarbons include mineral oil, petrolatum, and polyalphaolefins. Examples of preferred volatile hydrocarbons include polydecanes, such as isodecane and isododecane, and C 7 -C 8 ~C 12 -C 15 Examples include isoparaffins.

[0047] The cosmetic compositions of the present invention can include vitamins as desired actives. Exemplary vitamins include vitamin B 2 , Vitamin B 3 (niacinamide), vitamin B 5 (Panthenol), Vitamin B 6、Vitamin C, Vitamin E, folic acid and biotin. Derivatives of vitamins can also be used. For example, vitamin C derivatives include ascorbyl tetraisopalmitate, magnesium ascorbyl phosphate and ascorbyl glycoside. Derivatives of vitamin E include tocopheryl acetate, tocopheryl palmitate and tocopheryl linoleate. When present in the cosmetic composition according to the present invention, the total amount of vitamins may range from 0.001 to 10% by weight of the cosmetic composition, preferably 0.01 to 5% by weight, optimally 0.05 to 2.5% by weight.

[0048] Optional actives suitable for use in the present invention include resveratrol, saccharide isomerates, ceramides (e.g., ceramide 1, ceramide 3, ceramide 3B, and ceramide 6) and pseudoceramides, allantoin, pentaerythrityl tetradi-t-butyl hydroxyhydrocinnamate, salicylic acid, pyroglutamic acid (PCA) salt derivatives, such as zinc PCA and sodium PCA, 12-hydroxystearic acid, petroselinic acid, conjugated linoleic acid, octadecanoic acid, hyaluronic acid and its salt derivatives, and mixtures thereof. If used, such actives will collectively comprise 0.001 to 12% by weight of the cosmetic composition.

[0049] A wide selection of plant extracts can be optionally included in the cosmetic composition of the present invention. The extracts can be soluble in water or oil, and can be included in hydrophilic or hydrophobic solvents, respectively. In a preferred embodiment, water or ethanol is the extraction solvent. Examples include extracts from green tea, yarrow, chamomile, licorice, aloe, satsuma mandarin, willow bark, alfalfa, algae, witch hazel, sage, thyme and rosemary, as well as oils such as sea buckthorn, moringa, argan, avocado, calendula, algae, marula and hemp seed. Soybean extracts can be used, especially when it is desired to include retinol.

[0050] Conventional buffers or pH adjusters are also suitable for inclusion in the cosmetic compositions of the present invention. These include common additives such as sodium hydroxide, potassium hydroxide, hydrochloric acid, citric acid, triethanolamine and aminomethylpropanol. In a preferred embodiment, the pH of the cosmetic compositions of the present invention is 4 to 8, more preferably 4.25 to 7.75, and most preferably 5 to 7.5. The viscosity of the cosmetic compositions of the present invention can be measured at ambient temperature and 1 s using a strain-controlled parallel plate rheometer available from suppliers such as TA Instruments (Discovery). -1 The viscosity is preferably about 1,000 to about 120,000 cps, and most preferably about 5,000 to 80,000 cps, measured under conditions of a shear rate of 100 / min. Alternatively, the viscosity can be measured using a Brookfield Viscometer (speed 20 rpm, spindle 5, Heliopath off, ambient temperature for 1 minute). The cosmetic composition of the present invention can be formulated as a lotion having a viscosity of 4,000 to 10,000 mPas, a fluid cream having a viscosity of 10,000 to 20,000 mPas, or a cream having a viscosity of 20,000 to 100,000 mPas or more.

[0051] Preservatives may be incorporated into the compositions of the present invention, if desired, to protect against the growth of potentially harmful microorganisms. Cosmetic chemists are familiar with suitable preservatives and routinely select them to satisfy preservative and product stability tests. Preservative systems should be selected having regard to the intended use of the composition and possible incompatibilities between the preservatives and other ingredients in the formulation. Representative examples of preservatives for the compositions of the present invention include, but are not limited to, iodopropynyl butylcarbamate (IPBC), phenoxyethanol, ethylhexylglycerin, 1,2-octanediol, methylparaben, propylparaben, imidazolidinyl urea, sodium dehydroacetate, propanediol, alkyl esters of parahydroxybenzoic acid, hydroxyacetophenone, DMDM ​​hydantoin derivatives, climbazole, propionate salts, and various quaternary ammonium compounds. Preservatives are preferably used in amounts ranging from 0.01 to 2% by weight of the composition, including all ranges therein.

[0052] In preparing the cosmetic composition of the present invention, the desired ingredients are mixed in a conventional manner. If applicable, the oil and water phases are mixed separately using a standard mixer and mixing blades and heated to the same temperature, usually about 25 to about 85° C., at atmospheric pressure. Once the desired temperature is reached, the oil phase is added to the water phase to form an emulsion. The other ingredients in the cosmetic composition are then added and mixed, in any order.

[0053] The cosmetic compositions of the present invention are compositions suitable for topical application to human skin, including leave-on and wash-off products. Preferably, the term includes flowable liquids, and in particular moisturizing products, rather than makeup products. Most preferred are leave-on compositions. The term "leave-on" as used herein with respect to compositions means a composition that is applied or rubbed onto the skin and left on its surface.

[0054] Many types of packaging can be used to store and deliver the composition of the present invention. The choice of packaging depends on the personal care end use and the viscosity of the composition itself. As an example, leave-on lotions and leave-on creams for skin typically use plastic containers with an opening at the dispensing end covered with a suitable closure. Traditional closures include flip-top hinged lids, screw caps and non-aerosol pumps. As another example, suitable packaging for antiperspirants, deodorants and depilatories includes containers with rollerball applicators at the dispensing end when the composition is fluid and has a lower viscosity. When the composition is in stick form, a container with a propellant-rebound mechanism, where the stick is fixed on a platform toward the dispensing orifice, is suitable. When the composition is in aerosol form, a metal can pressurized by a propellant and with a spray nozzle is suitable. Generally, patches, bottles, tubes, rollerball applicators, squeeze containers or jars with lids are preferred.

[0055] The following examples will facilitate a more complete understanding of the invention and are not intended to limit the scope of the claims. EXAMPLES

[0056] Working Example All samples were prepared by mixing the above ingredients under conditions of moderate shear, ambient temperature to about 85° C., and atmospheric pressure. [Table 1] [Table 2]

[0057] As can be seen from the data, the oils used in accordance with the present invention unexpectedly stabilize formulations having both HR and RP: formulations containing greater than 13% oil have lower ΔE values ​​over time than formulations containing 10% oil. [Table 3]

[0058] Sample (a) is δ t C is 14.4 12-13 Alkane oil. Sample (b) has a δ t Sample (c) is isopropyl myristate with a δ t The sample (d) is a caprylic / capric triglyceride with a δ t is benzyl alcohol with a value of 24.7. t The data is collected from "CRC Handbook of Solubility Parameters and Other Cohesion Parameters, Second Edition (by Allan FM Barton)". From the data in this example, δ t It is demonstrated that oils having higher ΔE values ​​result in lower ΔE values ​​(ie, better color stability) over time. [Table 4] [Table 5] [Table 6]

[0059] Surprisingly, when compared to the HR and RP samples containing only the individual antioxidants, the compositions containing BHT and Tinogard DA are shown to exhibit lower ΔE values ​​over time, even though all sample compositions start out with similar ΔE values ​​at two weeks. [Table 7]

[0060] The above data unexpectedly demonstrate that 4:1 and 1:4 ratios of BHT to Tinogard DA in O / W based formulations containing HR and RP exhibit low ΔE values ​​over time and therefore excellent color stability. [Table 8]

[0061] Tinogard TT is a phenolic antioxidant sold under the chemical name "Pentaerythrityl Tetra-di-t-butyl Hydroxyhydrocinnamate" by BASF. Rosamox is a natural antioxidant sold under the chemical name "Rosmarinus officinalis (Rosemary) Leaf Extract" by Kemin.

[0062] The above results show that for the purposes of evaluating color stability with alkylresorcinols and retinoids, many other antioxidants were tested in the base formulation provided in Example 1. These other antioxidants, alone or in combination with additional potential antioxidants, were surprisingly not as effective as that seen with the BHT-Tinogard DA combination consistent with the present invention.

Claims

1. 1. A cosmetic composition comprising: (a) an oil-soluble alkylresorcinol; (b) a retinoid; (c) an oil, wherein the oil has a Hansen total solubility parameter of 16 to 22; and (d) an active mixture of BHT and dilauryl thiodipropionate, wherein the weight ratio of BHT to dilauryl thiodipropionate is from 0.8:4.2 to 4.2:0.8; Including, 1. The cosmetic composition, wherein said composition comprises 14-28% by weight of said oil, 0.001-10% by weight of said oil soluble alkylresorcinol, and 0.001-10% by weight of a retinoid, and said active mixture of BHT and dilauryl thiodipropionate is present in a minimum total weight percentage of 0.15% by weight of said cosmetic composition.

2. 2. The cosmetic composition of claim 1, wherein said alkylresorcinol is selected from the group consisting of 4-hexylresorcinol, 4-phenylethylresorcinol, 4-cyclopentylresorcinol, 4-cyclohexylresorcinol, and mixtures thereof.

3. 10. The cosmetic composition of claim 1, wherein said retinoid comprises retinol, retinal esters, retinoic acid, retinyl esters, and mixtures thereof.

4. 2. The cosmetic composition of claim 1, wherein said composition comprises a ratio of BHT and dilauryl thiodipropionate of 0.8:2.2 to 2.2:0.

8.

5. 10. The cosmetic composition of claim 1, wherein said composition comprises a ratio of BHT and dilauryl thiodipropionate of 0.8:1.2 to 1.2:0.

8.

6. 10. The cosmetic composition of claim 1, wherein said composition comprises an oil having a Hansen total solubility parameter of 17-19.

7. The cosmetic composition of claim 1, wherein the composition comprises 15 to 25% by weight of oil.

8. 10. The cosmetic composition of claim 1, wherein said composition comprises an oil selected from isopropyl myristate, isopropyl palmitate, caprylic / capric triglyceride, or mixtures thereof.

9. 10. The cosmetic composition of claim 1, wherein said composition further comprises at least one of niacinamide, 12-hydroxystearic acid, a sunscreen, a wrinkle reducing agent, or mixtures thereof.

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