Patent Application
20070276033
This invention relates to compositions that include both water-soluble and oil-soluble components.
More particularly, the invention relates to compositions that stabilize simultaneously water-soluble and oil-soluble ingredients.
In a further respect, the invention relates to ascorbic acid compositions that stabilize unusually large concentrations of vitamin C and vitamin E.
In another respect, the invention relates to a stabilized ascorbic acid-vitamin E composition that utilizes water in stabilizing ascorbic acid and vitamin E.
In still a further respect, the invention relates to a composition that utilizes a rheology modifier to absorb water to stabilize water-soluble and oil-soluble components in the composition.
In still another respect, the invention relates to a composition that utilizes a water miscible organic solvent to stabilize water-soluble and oil-soluble components in the composition.
The following terms used herein have the meanings set forth below.
Vitamin C, also known as L-ascorbic acid, is water-soluble. Vitamin C is unstable in the presence of air when the vitamin C is in an aqueous medium. Therefore, vitamin C is unstable in water-based cosmetic formulations. Eliminating water from cosmetic formulations cures this problem. Aqueous cosmetic formulations in which vitamin C is stable can also be obtained by removing air from the formulations and by storing the formulations in an airtight container.
Hydroquinone is a water-soluble skin-whitening ingredient. Hydroquinone, like vitamin C, is also unstable when in a water-based formulation exposed to air. Further, when both vitamin C and hydroquinone are present in a water-based formulation, serious discoloration occurs when the formulation is exposed to air.
Current stable non-aqueous vitamin C products typically contain compositions such as waxes or combinations of waxes, oils, glycols, and siloxane elastomers. These compositions promote the stability of the vitamin C but leave an oily or waxy residue on skin after use. This residue is unappealing and unaesthetic.
Another solution to the instability of vitamin C in aqueous compositions is to use modified forms of vitamin C in aqueous formulations. Modified or derivative forms of vitamin C include ascorbic acid glucoside, sodium ascorbyl phosphate, magnesium ascorbyl phosphate, calcium ascorbyl phosphate, ester C, ascorbyl palmitate, and tetrahexyldecyl ascorbate. Formulations with modified forms of vitamin C have proven expensive, not equivalent in efficacy on an equal weight basis, or have encountered other problems that adversely affect the successful sale of such formulations. Modified forms of vitamin C, such as oil-soluble ascorbyl palmitate in combination with vitamin C can, however, be beneficial for certain topical applications.
Recent reports indicate that combining vitamin C with significant amounts of certain oil-soluble ingredients such as vitamin E and a sunscreen can provide synergistically enhanced skin protection. For example, a combination of vitamin C (10% by weight), vitamin E (2% by weight), and Benzophenone-3 (0.25% by weight) was found effective. Additional examples of synergistically beneficial effects of the combination of vitamins C and E have also been reported.
Consequently, it would be highly desirable to provide formulations that contain both water-soluble and oil soluble ingredients, and, in particular, to have such formulations in which the combination of water-soluble and oil-soluble ingredients provide known synergistic benefits. The formulation of compositions including water-soluble and oil-soluble ingredients is, however, difficult. One problem is that certain water-soluble vitamins like vitamin C are, as noted, inherently unstable in formulations that include any significant amount of water. Another problem is that vitamin C is not soluble in oil-soluble cosmetic ingredients. A further problem is that oil-soluble ingredients like vitamin E are not water-soluble. Still another problem is that the formulation of oil-soluble ingredients in a water-based formulation typically requires the use of an emulsifier. Several recent patents have addressed this problem. These patents include U.S. Pat. Nos. 6,235,272, 6,174,519, 6,036,946, and 4,704,280. Most of the preferred combinations of vitamins C and E in these patents permit only up to about 2.2% vitamin C and 0.5% vitamin E, even though the claims set forth up to 7.0% of vitamin C and up to 30.0% of vitamin E. None of the foregoing patents appear to claim more than 7.0% by weight vitamin C (a water soluble ingredient) in combination with any amount of vitamin E (an oil soluble ingredient). Brandt et al. (U.S. Pat. No. 6,696,067) discloses certain combinations of water soluble and oil soluble antioxidants, such as ascorbic acid, Vitamin E acetate, tocopherol, or ascorbyl palmitate, but only in amounts ranging from 0.01% to 5% by weight. The combinations over 5% are not possible by Brandt disclosure.
I have discovered an improved topical formulation that includes water-soluble and oil-soluble ingredients in typically much greater than 5% combinations. The formulation includes a water-soluble composition(s), an oil-soluble composition(s), water, a rheology modifier(s), and a water-miscible organic solvent(s). One advantage of the topical formulation of the invention is that it ordinarily does not impart a sticky or oily skin feel. In most cosmetic formulations, both vitamin C and vitamin E produce a sticky feel when applied in substantial amounts to skin.
Water is critical in the formulation of the invention because water dissolves at least a portion of water-soluble ingredients. The water-water-soluble ingredient solution is then acted on by the rheology modifier and the water miscible organic solvent to stabilize the water-soluble ingredient.
The rheology modifier is, in combination with the water, critical in the formulation of the invention because it functions to stabilize both the water-soluble composition and the oil-soluble composition. A portion of the water-soluble composition dissolves in the water. A portion of the water is absorbed by the rheology modifier. When the rheology modifier absorbs water it swells, i.e., the volume of the rheology modifier increases. The portion of water-soluble composition(s) that is in water absorbed by the rheology modifier is stabilized because the rheology modifier functions, practically speaking, to house and shield the water-soluble composition and to prevent it from dispersing from the rheology modifier. In addition, once a portion of the water is absorbed by the rheology modifier, the rheology modifier and oil-soluble composition form an emulsion. The formation of the emulsion further stabilizes the formulation because it makes it more difficult for the water-soluble composition to separate from the oil-soluble composition.
The water miscible organic solvent is also critical in the formulation of the invention because it solubilizes the water-soluble ingredient when the organic solvent mixes with the water. When the organic solvent and water mix, separation of the water-soluble composition and oil soluble composition is made yet more difficult. As noted below, the organic solvent also functions to stabilize the oil-soluble ingredient(s) in the formulation.
The amount of water-soluble composition in the formulation is from over 5% to up to 30.0% by weight, preferably from over 7% up to 30.0% by weight, and most preferably from over 10% up to 30% by weight. A particular advantage of the invention is that relatively large amounts of ascorbic acid, from over 5% to up to about 30% by weight can be combined with relatively large amounts of vitamin E or other oil-soluble components. If the amount of the water-soluble ingredient is in excess of 30%, the amount of water required becomes excessive. Consequently, quantities of ascorbic acid or other water-soluble compositions greater than about 30% are presently not practical in the practice of the invention. It is theorized that this is the case because as more water-soluble compositions are utilized, more water is required. And, the amount of water appears limited by the amount of water-miscible organic solvent required.
The amount of oil-soluble composition in the formulation is 0.05% to 30% by weight, preferably from 1.0% to 25.0% by weight, most preferably from 2% to 25% by weight. The amount of oil-soluble composition in the formulation can also be from 5% to 25% because one of the advantages of the invention is being able to incorporate unusually large amounts of an oil-soluble composition.
The amount of rheology modifier in the formulation is from 0.05% to 10% by weight, preferably from 0.5% to 5.0% by weight.
The amount of water in the formulation is from 0.05% to 25%, preferably 0.05% 19%, most preferably 1.0% to 15% by weight.
The amount of water-miscible organic solvent in the formulation is from 5% to 82%, preferably 7.5 to 82% by weight, and most preferably 10.0% to 80.0% by weight. The use of a water miscible organic solvent is believed critical in the practice of the invention because it facilitates the intermixing of water—which contains at least a portion of the water-soluble composition—with the organic solvent. Further, the organic solvent functions to help the suspension of oil-soluble ingredients as micro-droplets. These micro-droplets do not coalesce to make bigger droplets in the present of the organic solvent. In addition, when water mixes with the organic solvent, each molecule of water occupies an empty space among the organic solvent molecules, and the organic solvent molecules function to interfere with the coalescing of the water into larger droplets.
The amount of water in the formulation is from 0.05% to 25%, preferably 1% to 15%. As earlier discussed, in many cosmetic formulations water is excluded to increase the stability of the ascorbic acid and decrease the likelihood that oil-soluble ingredients will separate from the formulation. In contrast, in the formulation of the invention, water is desirable and required in the formulation for reasons set forth above.
The proportion of water to water-miscible organic solvent in the formulation appears to be important in terms of vitamin C stability and is in the range of 1:2 to 1:5, preferably 1:3 to 1:4. This proportion is believed important (although this belief has not presently been proven) because there must be sufficient water-miscible organic solvent to absorb and/or mix with water containing vitamin C to stabilize the vitamin C and to facilitate the suspension of micro-droplets of oil soluble ingredients. The rheology modifier works hand-in-hand with the organic solvent because the rheology modifier absorbs some of the water in the formulation.
Water used in the formulations of the invention can be provided by direct addition of water, can be provided from other ingredients in the formulation that contain water in their own composition, or can consist of water from hydrated ingredients.
Other water soluble or water dispersible ingredients that can be used in the formulation of the invention include, by way of example and not limitation, other vitamins, anti-inflammatory agents, anesthetics, analgesics, enzymes, UV-absorbers, antiperspirants, deodorants, colorants, hydroxy aids, skin lightening agents, emollients, medications, antibiotics, antifungal agents, and insect repellents. If desired, such ingredients need not be water-soluble or water dispersible. Such ingredients can, if desired, be oil-soluble.
The following examples are presented by way of illustration, and not limitation, of the invention. In each example, the amount or proportion of each ingredient is in weight percent unless otherwise indicated.
The following ingredients are provided.
The ascorbic acid is added to the water. The remaining ingredients are mixed separately and are then added to the aqueous ascorbic acid solution to produce a facial and body cream. The cream is put in a container.
The following ingredients are provided.
All of the ingredients are mixed. The mixture is heated and stirred at 60 to 70 degrees C. until the mixture is homogenous, i.e., for about five to ten minutes. The homogeneous mixture is cooled to room temperature. A skin cream is produced. The cream is put in a container. This example demonstrates the use of an oil-soluble silicone derivative (Jeechem HPIB, which is a blend of polydimethylsiloxane, cyclized dimethicone, and cyclomethicone) in combination with ascorbic acid and vitamin E acetate.
The following ingredients are provided.
All of the ingredients are mixed. The mixture is heated and stirred at 60 to 70 degrees C. until the mixture is homogenous, i.e., for about five to ten minutes. The homogeneous mixture is cooled to room temperature. A skin cream is produced. The cream is put in a container. This example demonstrates the use of an oil-soluble form of vitamin C.
The following ingredients are provided.
All of the ingredients are mixed. The mixture is heated and stirred at 60 to 70 degrees C. until the mixture is homogenous, i.e., for about five to ten minutes. The homogeneous mixture is cooled to room temperature. A skin lotion is produced. The cream is put in a container. This example demonstrates the preparation of a skin whitening formula that contains ascorbic acid, lactic acid and hydroquinone with water. Both ascorbic acid and hydroquinone are known in prior art to easily oxidize when water and air are both present.
The following ingredients are provided.
All of the ingredients are mixed. The mixture is heated and stirred at 60 to 70 degrees C. until the mixture is homogenous, i.e., for about five to ten minutes. The homogeneous mixture is cooled to room temperature. A skin lotion is produced. The cream is put in a container. This example demonstrates the use of ascorbyl palmitate in a silicone surfactant base. The amount of hydroquinone and/or hydroquinone derivative in a composition of the invention is in the range of 0.1% to 10% by weight, preferably 1% to 4% by weight. The amount of sodium ascorbyl palmitate in a composition of the invention is in the range of 0.01% to 10.0%.
The cream of Example I is stored at room temperature in a container. A lid is laid across the top of the container to slow evaporation. The lid does not prevent ambient air from slowly entering the container. After six months the color of the cream has not changed.
The cream of Example I is stored at room temperature in a container. A lid is laid across the top of the container to slow evaporation. The lid does not prevent ambient air from slowly entering the container. After one year the color of the cream has changed slightly and is somewhat darker.
Examples VI and VII are repeated, except the cream of Example II is utilized instead of the cream of Example I. Similar results are obtained.
Examples VI and VII are repeated, except the lotion of Example III is utilized instead of the cream of Example I. Similar results are obtained.
Examples VI and VII are repeated except that the lotion of Example IV is utilized instead of the cream of Example I. Similar results are obtained.
Examples VI and VII are repeated except that the cream of Example V is utilized instead of the cream of Example 1. Similar results are obtained.
The following ingredients are provided.
A composition is prepared using the process used to prepare to lotion of Example V. A liquid serum is obtained.
The following ingredients are provided.
A composition is prepared using the process used to prepare the lotion of Example V. A white, liquid lotion is obtained.
This example shows the formulation of Benzocaine, a water-insoluble topical analgesic ingredient with glycerin, a water-soluble ingredient.
Mix ingredients 2, 3 and 4 together until a clear gel is formed. Add all other ingredients, except 9 and 10, to the gel and mix to form the main batch. Mix ingredients 9 and 10 together and heat at 40 to 50 degrees C. to form a clear solution. Add this solution to the main batch with mixing and cool to room temperature. A clear cream is obtained. The cream contains a solubilized form of benzocaine that is highly bioavailable.
This example shows the formulation of Progesterone, an oil-soluble hormone.
Mix ingredients 2, 3 and 4 together until a clear gel is formed. Add all other ingredients, except 9 and 10, to the clear gel and mix to produce a main batch. Mix ingredients 9 and 10 together and heat at 40 to 50 degrees C. to form a clear solution. Add this solution to the main batch with mixing and cool to room temperature. A clear cream is obtained. The cream contains solubilized form of progesterone that is highly bioavailable.
This example shows the formulation of both water-soluble and oil-soluble sunscreen ingredients in the same formula.
Mix ingredients 2, 3 and 4 together until a clear gel is formed. Add all other ingredients, except 9, 10, 11, 12, and 13, to the clear gel and mix to form a main batch. Mix ingredients 9, 10, 11, 12 and 13 together and heat at 40 to 50 degrees C. to form a clear solution. Add this clear solution to the main batch with mixing and cool to room temperature. A clear, light yellow lotion is obtained. This contains solubilized form of sunscreen that is very cosmetically appealing and very effective at blocking UV light.
This example shows the formulation of oil-soluble and water-soluble botanical cosmeceuticals for body slimming and muscle-firming benefits.
Mix ingredients 2, 3, and 4 together until a clear gel is formed. Add ingredients 1, 5, 6, 7, 10, 11, and 13 to the clear gel and mix to form a main batch. Mix ingredients 8, 9, and 12 together and heat at 40 to 50 degrees C. to form a solution. Add the solution to the main batch and mix. Cool to room temperature. A translucent cream is obtained.
This example shows the formulation of Aloe Vera, a water-soluble skin care ingredient, and Progesterone, an oil-soluble skin care and medicinal ingredient. Additional oil-soluble skin-smoothing ingredients, such as several silicone derivatives and Vitamin E, are also included.
Mix ingredients 2, 3, 4, and 5 together until a clear gel is formed. Add ingredients 1, 6, 7, 8, 9, 10, and 11 to the clear gel and mix to form a main batch. Mix ingredients 12 and 13 together and heat at 50 to 60 degrees C. to form a solution. Add the solution to the main batch and mix. A translucent cream is obtained. The cream is rapidly absorbed by the skin on application.
This example shows in-situ preparation of Nicotinamide Ascorbate, a water-soluble ingredient, and its formulation with oil-soluble vitamin E acetate.
Mix ingredients 2, 3, and 4 together until a clear gel is formed. Add ingredients 1, 5, 6, 7, 8, 9, 10, and 11 to the clear gel and mix. A translucent cream is obtained. The cream is rapidly absorbed by skin on application.
A liquid serum product with water-soluble ingredients, ascorbic acid and Glucosamine, and oil-soluble ingredients, Vitamin A and Vitamin E.
Glucosamine HCl is dissolved in water to form a solution. The solution is neutralized with caustic soda to pH 6.5. All other ingredients are added to this neutralized solution and the resulting composition is mixed at 40 to 50 degrees C. for 30 minutes. The composition is cooled to room temperature. A gel-like product is obtained.
This example shows the formulation of a complex mixture of water-soluble and oil-soluble compositions.
The Aristoflex, glycerin, and deionized water are mixed together to form a clear gel. The Vitamin E Acetate, Centella Asiatica, Tetrahydrocurcumin, Escin, Esculine, Boswellia Serata and PEG (20% portion) are mixed together to form a solution. This solution is mixed together with the gel to form a primary mixture, then the other remaining ingredients are added to the primary mixture to form a final composition. The final composition is heated to a temperature in the range of 50 degrees C. to 60 degrees C. and is mixed. The final composition is then cooled to room temperature to form a cream.
Having described the presently preferred embodiments and best mode of the invention in such terms as to enable those of skill in the art to understand and practice the invention, I Claim:
This application is a continuation-in-part of application Ser. No. 11/126,013, filed May 10, 2005, which is a continuation-in-part of application Ser. No. 10/307,240, filed Nov. 29, 2002.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11126013 | May 2005 | US |
| Child | 11716833 | Mar 2007 | US |
| Parent | 10307240 | Nov 2002 | US |
| Child | 11126013 | May 2005 | US |
