JPH08245358A - Vitamin c delivery system - Google Patents

Abstract

PURPOSE: To obtain the subject system comprising ascorbic acid and a pharmaceutically acceptable carrier in a specific ratio, excellent in the storage stability of the ascorbic acid and facilitating the penetration of the ascorbic acid into human skin without irritating the skin. CONSTITUTION: This anhydrous cosmetic composition comprises (A) about 0.001-50 wt.%, preferably about 0.01-10 wt.%, of ascorbic acid and (B) about 0.10-99.9 wt.%, preferably about 25-90 wt.%, of a pharmaceutically acceptable carrier of the formula [(n) is an integer of 20-50, preferably 5-10]. The composition is preferably further compounded with about 0.1-20 wt.% of an acidifying agent and about 0.5-20 wt.% of an emulsifier [preferably a polyoxyalkylenepolyol fatty acid ester, especially preferably polyoxyethyleneoxide(15)-trimethylolpropane isostearate].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cosmetic product capable of stably storing ascorbic acid and then delivering it to the skin.

[0002]

BACKGROUND OF THE INVENTION Ascorbic acid, also known by the trivial name of vitamin C, has long been recognized as an active substance that improves the appearance of the skin. Vitamin C has been reported to increase collagen production in human skin tissue. Therefore,
By administering vitamin C, large and small wrinkles can be reduced. The result is a healthier, more youthful overall appearance. Vitamin C has also been found to be useful as a UV blocker or absorber. Vitamin C has also been used in skin lightening or bleaching compositions due to its properties of interfering with the melanogenesis process. Ascorbic acid is also believed to interact with the human immune system and reduce sensitivity to cutaneous inflammatory chemicals. Decreased skin vitamin C levels have also been linked to increased stress. From all of the above perspectives, topical administration of vitamin C or ascorbic acid can be very advantageous.

However, vitamin C is a very unstable substance. It is readily soluble in water but oxidizes rapidly in aqueous media. The solubility of ascorbic acid in non-aqueous media has been reported to be relatively low, and therefore it is not possible to reach significant levels of active substance concentrations in anhydrous systems.

The prior art attempts to solve the problem in various ways. One approach is the production of ascorbic acid derivatives. These derivatives are more stable than the parent compound and can be converted to the parent acid at the point of use via bioconversion or chemical hydrolysis. For example, US Pat. No. 5,137,723 (Yamamoto et al.) And US Pat. No. 5,078,989 (Ando et al.) Provide glycosylate and ester derivatives, respectively.

US Pat. No. 4,818,521 (Tam
abuchi) describes in the background section a so-called two-pack cosmetic in which vitamin C powder and other ingredients are separately packaged in separate containers and mixed immediately before use of the cosmetic. He states that mixing methods and expensive packaging are the drawbacks of this system. The patent proposes a weakly acidic stable oil-in-water emulsion in which ascorbic acid is premixed with a stabilizer oil.

US Pat. No. 5,140,043 (Dar
It has also been proposed in R et al.) to maintain the pH below about 3.5 as a means of stabilizing an aqueous composition of ascorbic acid.

Water-compatible alcohols such as propylene glycol, polypropylene glycol and glycerol have been proposed as auxiliary carriers for use with water to improve stability. One example of this approach is U.S. Pat. No. 4,983,382 (Wilmott and Zn.
aiden). The patent uses a blend of water and a water-miscible organic solvent as the stabilizing system. At least about 40% of the organic solvent should be ethanol and the balance may be selected from alcohols such as propylene glycol, glycerin, dipropylene glycol and polypropylene glycol.

US Pat. No. 4,372,874 (Mod
Rovich) have reported the incorporation of relatively large amounts of ascorbic acid in polar water-miscible organic solvents such as dimethylsulfoxide. The water concentration is maintained below 0.5% by adding a particulate desiccant to the carrier. Although highly polar systems such as dimethylsulfoxide may be effective, such systems and associated carriers are toxicologically problematic.

[0009]

Accordingly, it is an object of the present invention to provide an ascorbic acid delivery system in which the ascorbic acid is storage stable.

Another object of the present invention is to provide a delivery system which facilitates penetration of ascorbic acid into human skin while avoiding irritation.

Yet another object of the present invention is to provide an ascorbic acid delivery system that is sufficiently transparent to aesthetically enhance the appearance of the system.

[0012]

The above and other objects of the invention are set forth in the Summary, Detailed Description and Examples section below.

The present invention provides (i) about 0.0 ascorbic acid.
01 to about 50% by weight, and formula (ii):

[0014]

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The pharmaceutically acceptable carrier (wherein n is an integer from 2 to 50) is from about 0.10 to about 99.9.
It relates to an anhydrous cosmetic composition consisting of wt%.

It has been found that ascorbic acid can be stably dissolved in anhydrous compositions containing selected pharmaceutically acceptable carriers. The carrier of the present invention has the formula:

[0017]

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(In the formula, n is 2 to 50, preferably 4 to 2
0, more preferably an integer of 5-10).

Carbowax 400 and Carbo
Wax 200 was found to be the polyethylene glycol of choice.

Generally, the carrier is the component present in the anhydrous composition in the maximum amount. The amount is about 10 to about 99.9% by weight, preferably about 25 to about 90% by weight, optimally about 7%.
It can be 0 to 85% by weight.

Lower alcohols such as ethyl alcohol may be incorporated to aid the carrier. However, the lower alcohol concentration should be 40% by weight or less, preferably 0.1 to about 25% by weight.

Another essential ingredient of the invention is of course ascorbic acid. The amount of ascorbic acid is from about 0.001 to about 50% by weight of the anhydrous composition, preferably about 0.0.
It should be 1 to about 10% by weight, optimally about 3 to about 6% by weight.

Esters may also be incorporated into the anhydrous composition as emollients. The esters that can be used are listed below.

(1) Fatty acid alkyl esters having 10 to 20 carbon atoms. Methyl, isopropyl and butyl esters of fatty acids are useful in the present invention. For example, hexyl laurate, isohexyl laurate, isohexyl palmitate, isopropyl palmitate, decyl oleate, isodecyl oleate, hexadecyl stearate, decyl stearate, isopropyl isostearate, diisopropyl adipate, diisohexyl adipate. , Dihexyldecyl adipate, diisopropyl sebacate, lauryl lactate, myristyl lactate and cetyl lactate. Particularly preferred are C ₁₂ -C ₁₅ alcohol benzoates.

(2) Fatty acid alkenyl esters having 10 to 20 carbon atoms. Examples include oleyl myristate, oleyl stearate and oleyl oleate.

(3) Ether-esters such as fatty acid esters of ethoxylated fatty alcohols.

(4) Polyhydric alcohol esters. Ethylene glycol mono and di fatty acid esters, diethylene glycol mono and di fatty acid esters, polyethylene glycol (200-6000) mono and di fatty acid esters, propylene glycol mono and di fatty acid esters, polypropylene glycol 2000 monooleate, polypropylene glycol 2000 monostea Rate, ethoxylated propylene glycol monostearate, glyceryl mono- and difatty acid esters, polyglycerol polyfatty esters, ethoxylated glyceryl monostearate, 1,3-butylene glycol monostearate, 1,3-butylene glycol distearate Rate, polyoxyethylene polyol fatty acid ester, sorbitan fatty acid ester, and polyoxyethylene sorbitan Fatty acid esters are satisfactory polyhydric alcohol esters.

(5) Wax esters such as beeswax, spermaceti, myristyl myristate and stearyl stearate.

(6) Sterol esters, for example cholesterol fatty acid esters.

An emulsifier may also be included in the composition of the present invention.
These emulsifiers may be of anionic, nonionic, cationic or amphoteric type. Nonionic emulsifiers, especially polyoxyalkylene polyol fatty acid esters (which may also function as ester emollients), are particularly suitable. Polyethylene oxide (15) trimethylolpropane isostearate is most suitable. The emulsifier concentration is in any case about 0.1 to about 20% by weight, preferably about 1
Can be ˜5% by weight.

Silicone oils may also be included in the compositions of this invention. The silicone oil may be volatile or non-volatile. 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 or linear polydimethylsiloxanes having from about 3 to about 9, preferably from about 4 to about 5, silicon atoms.

Linear volatile silicone materials are generally at 25 ° C.
Has a viscosity of less than about 5 centistokes, and the annular material generally has a viscosity of less than about 10 centistokes.

Suitable volatile silicone oils useful in the present invention are, for example, Dow Corning 344, Dow C.
orning 345 and Dow Corning 2
00 (manufactured by Dow Corning Corp.); Si
silicone 7207 and Silicone 715
8 (manufactured by Union Carbide Corp.); S
F 1202 (General Electric
Manufactured); and SWS-03314 (SWS Silic
ones, Inc. Made).

Nonvolatile silicone oils useful in the compositions of the present invention are, for example, polyalkyl siloxanes, polyalkylaryl siloxanes and polyether siloxane copolymers. The substantially non-volatile polyalkyl siloxanes useful in this invention are, for example, from about 5 to about 100,000 at 25 ° C.
It is a polydimethylsiloxane having a viscosity of centistokes. Suitable non-volatile silicones useful in the compositions of the present invention include polydimethylsiloxanes having viscosities of from about 10 to about 400 centistokes at 25 ° C. Examples of such polyalkyl siloxane include V
iscasil series (General Select
(commercially available from ric Company) and Dow Cor
Ning 200 series (Dow Corning
Commercially available from Corporation). As a polyalkylaryl siloxane, about 15 at 25 ℃
Included are poly (methylphenyl) siloxanes having viscosities of about 65 centistokes. These materials are, for example, SF 1075 Methyl Phenyl Fluid (Gene
Ral Electric Company) and 556 Cosmetic Grade Fluid
(Sold by Dow Corning Corporation). Useful polyether siloxane copolymers include, for example, about 1200 at 25 ° C.
Mention may be made of polyoxyalkylene ether copolymers having a viscosity of ˜1500 centistokes. Such fluids include SF-1066 organosilicone surfactants (General Electric Company).
It is marketed as (sale). Cetyl dimethicone copolyol and cetyl dimethicone are particularly suitable because they also function as emulsifiers and emollients.

Other skin improvers that may be incorporated into the anhydrous compositions of the present invention are fatty acids containing 10 to 20 carbon atoms. Suitable examples of fatty acids 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 and erucic acid. These materials may be present in about 0.1 to about 20% by weight of the anhydrous composition, preferably about 2 to 10%.

Acidifying agents may also be included in the anhydrous composition. The acidifying agent may be an organic material or an inorganic material, and its amount is about 0.1 to about 20% by weight, preferably about 1 to 10% by weight,
Optimally about 2-6% by weight. Examples of acids include alginic acid, citric acid, malic acid, succinic acid, lactic acid, glycolic acid, tartaric acid, sorbic acid, phosphoric acid, acidic phosphate,
Acid pyrophosphates, bitartrates and metal acid citrates are mentioned.

The preferred use of the anhydrous cosmetic composition according to the invention is as one phase of a two-phase cosmetic product. The second composition of the two phase cosmetic has a pH when blended with an anhydrous composition.
Can be an aqueous composition containing an alkaline agent to increase the A multi-compartment dispenser is used for such cosmetics. Applicant subject No. 92-
The 0310-EA co-pending application is directed to this alternative development in ascorbic acid delivery.

The present invention will be further described below with reference to examples. All parts, percentages and proportions used herein and in the claims are by weight unless otherwise specified.

[0039]

EXAMPLES Example 1 Carbowax 400 (polyethylene glycol)
84.0% by weight, ascorbic acid (vitamin C) 5.0
An anhydrous composition of the present invention having a composition of wt%, ethyl alcohol 5.0 wt%, anhydrous citric acid 3.0 wt%, isostearic acid 3.0 wt% was prepared.

Example 2 Carbowax 200 82.0% by weight, ascorbic acid (vitamin C) 5.0% by weight, ethyl alcohol 5.0% by weight, glycolic anhydride 3.0% by weight, isostearic acid 3.0% by weight , Another anhydrous composition of the present invention having a composition of 2.0 wt% dimethicone was prepared.

Example 3 83.0% by weight of Carbowax 400, 5.0% by weight of ascorbic acid (vitamin C), 5.0 of glycerin
Another anhydrous composition of the present invention having the composition of wt%, lactic acid anhydride 3.0 wt%, linolenic acid 2.0 wt%, dimethicone copolyol 2.0 wt% was prepared.

Example 4 76.0% by weight of Carbowax 200, 10.0% by weight of ascorbic acid (vitamin C), 5.0% by weight of ethyl alcohol, 3.0% by weight of malic anhydride, 3.0% by weight of oleic acid , Another polyoxyethylene 15 trimethylolpropane isostearate another anhydrous composition of the present invention having a composition of 3.0% by weight was prepared.

Example 5 Carbowax 400 80.9% by weight, isostearic acid 7.0% by weight, ascorbic acid (vitamin C)
Another anhydrous composition of the invention having the composition of 5.0% by weight, 5.0% by weight of ethyl alcohol, 2.0% by weight of polyoxyethylene 15 trimethylolpropane isostearate, 0.1% by weight of anhydrous citric acid. Was prepared.

Example 6 Various polyhydroxy compounds were evaluated as solvents for ascorbic acid. Table 1 shows the solubility of ascorbic acid in these materials. The notation "incompatible" refers to materials that showed visible signs of chemical reaction with ascorbic acid.
Materials considered insoluble did not dissolve enough ascorbic acid to produce a stable two-phase product. As can be seen from the table, only polyethylene glycol provided adequate solubility and compatibility.

[0045]

[Table 1]

The above description and embodiments are specific descriptions of selected embodiments of the present invention, and a person skilled in the art will come to various modifications within the spirit and scope of the present invention based on this description.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical indication location A61K 31/375 ADK A61K 31/375 ADK 47/10 47/10 B (72) Inventor Alan Jyoel・ Meyer's United States, Connecticut ・ 06611, Trumbull, Frederick Street ・ 68

Claims (7)

[Claims] 1. An ascorbic acid from about 0.001 to about 50% by weight, and (ii) a compound of the formula: An anhydrous cosmetic composition comprising from about 0.10 to about 99.9% by weight of a pharmaceutically acceptable carrier, wherein n is an integer from 2 to 50. 2. The cosmetic composition according to claim 1, wherein the amount of ascorbic acid is about 0.01 to about 10% by weight of the cosmetic composition. 3. The cosmetic composition of claim 1, further comprising about 0.1 to about 20% by weight of the composition of an acidifying agent. 4. The cosmetic composition according to claim 1, wherein n is an integer of 5 to 10. 5. The cosmetic composition of claim 1, further comprising about 0.5 to about 20% by weight emulsifier. 6. The cosmetic composition according to claim 5, wherein the emulsifier is a polyoxyalkylene polyol fatty acid ester. 7. The emulsifier according to claim 6, which is polyethylene oxide (15) trimethylolpropane isostearate.