CN-122028900-A - Depilatory composition

Abstract

The present invention relates to storage stable depilatory compositions comprising natural oils and cellulose-based ingredients and methods of use thereof. The composition provides effective hair removal over an acceptable contact time, and is well tolerated by the skin.

Inventors

• A. Alsini
• D M paves

Assignees

• 雷克特本克斯尔健康有限公司

Dates

Publication Date

20260512

Application Date

20241011

Priority Date

20231016

Claims (20)

1. 1. A depilatory composition comprising: (a) The natural oil is used as the natural oil, (B) An alkaline source is provided, which is a source of alkalinity, (C) The depilatory agent is used for the hair, (D) Water, and (E) C 1 -C 20 alkyl hydroxyalkyl cellulose, and The composition has a pH in the range of 10 to 12.9 measured as a 10% w/v aqueous solution at 30 ℃ plus or minus 0.5 ℃ or as a neat composition.
2. 2. The epilatory composition of claim 1 comprising: (a) 0.1 to 10% by weight of a natural oil, (B) 0.1 to 10% by weight of potassium hydroxide, (C) 0.5 to 10% by weight of potassium thioglycolate and/or thioglycollic acid, (D) At least 40% by weight of water, (E) 0.01 to 5% by weight of C 1 -C 20 hydroxyalkyl cellulose, The composition has a pH in the range of 10 to 12.9 measured as a 10% w/v aqueous solution at 30 ℃ or as a neat composition.
3. 3. The epilatory composition according to claim 1 or2, wherein the natural oil is selected from coconut oil, olive oil, palm oil, rapeseed oil, soybean oil, sunflower oil, avocado oil, almond oil, rapeseed oil, canola oil.
4. 4. A depilatory composition according to claim 3, wherein the natural oil is canola oil.
5. 5. The depilatory composition of any of claims 1, 3 and 4, wherein the composition comprises the natural oil in an amount of 0.01 to 10 wt%.
6. 6. The epilatory composition of any preceding claim, wherein the alkalinity source comprises potassium hydroxide.
7. 7. The epilatory composition according to any one of claims 1 or 3 to 6, wherein the alkaline source is present in a total amount of 0.01 to 5 wt%.
8. 8. The depilatory composition of any preceding claim, wherein the depilatory agent is potassium thioglycolate.
9. 9. The depilatory composition of any preceding claim, wherein the composition comprises from 0.5 to 10 wt% of the depilatory agent.
10. 10. The epilatory composition of any one of claims 1 or 3 to 9, wherein the composition comprises from 30 to 95 wt% water.
11. 11. The epilatory composition of any preceding claim, wherein the C 1 -C 20 alkyl hydroxyalkyl cellulose is cetyl hydroxyethyl cellulose.
12. 12. The depilatory composition of any of claims 1 to 10, wherein the C 1 -C 20 alkyl hydroxyalkyl cellulose is hydroxypropyl methylcellulose.
13. 13. The depilatory composition of any of claims 1 or 3 to 12, wherein the C 1 -C 20 hydroxyalkyl cellulose is present in an amount of 0.001 wt% to 5 wt%.
14. 14. The depilatory composition of any of claims 1 to 7 or 9 to 13, comprising: (a) 1.5 to 2.0% by weight canola oil, (B) 0.2 to 1.0 wt% potassium hydroxide, (C) 0.5 to 7% by weight of potassium thioglycolate and/or thioglycollic acid, (D) At least 65% by weight of water, (E) From 0.05 to 0.3% by weight of cetyl hydroxyethylcellulose and/or hydroxypropylmethyl cellulose, The composition has a pH in the range of 11.0 to 12.7 measured as a 10% w/v aqueous solution at 30 ℃ or as a neat composition.
15. 15. The epilatory composition according to any preceding claim, wherein the pH of the composition is in the range 11.0 to 12.7.
16. 16. The depilatory composition of any preceding claim, which is stable for at least one week when stored at 50 ℃.
17. Use of a C 1 -C 20 alkyl hydroxyalkyl cellulose to provide a shelf stable epilatory composition, wherein the composition comprises a natural oil, and wherein the composition is stable for at least one week at a temperature of from above the freezing point up to 50 ℃.
18. 18. Use of the epilatory composition according to any of the preceding claims for removing hair by applying the epilatory composition to a human body site from which hair is desired to be removed and contacting the epilatory composition with the hair for a time sufficient to degrade the hair sufficiently to allow it to be removed.
19. 19. A method of removing hair from human skin, the method comprising the steps of: (i) Applying the composition of any one of claims 1 to 16 to human skin in the presence of unwanted hair; (ii) Maintaining said composition in contact with said unwanted hair for a predetermined period of time, and (Iii) The composition and degraded excess hair are then removed from the skin.
20. 20. The method of claim 19, wherein the contact time on the skin is 1 to 10 minutes.

Description

Depilatory composition Technical Field The present invention relates to storage stable epilatory compositions and methods of use thereof. The composition provides effective hair removal over an acceptable contact time, while the skin is well tolerated. Background Compositions for removing unwanted hair from mammals are well known. Such compositions include depilatory compositions comprising compounds that degrade the keratin within the hair, weakening it and allowing removal. The depilatory composition is applied to the area containing the unwanted hair, allowed to remain thereon to degrade the hair, and then removed from the area with the degraded hair. Depilatory compositions of this type typically comprise a depilatory compound having thiol groups, such as potassium thioglycolate, and typically contain potassium hydroxide to provide a high pH that aids in hair removal efficacy. The epilatory composition typically has a pH of from 10 to 12.9. Depilatory compositions are typically stored at temperatures ranging from slightly above freezing (e.g., in a refrigerator or freezer) to as high as 50 ℃ in the global warmer climates. The temperature range to which the epilatory composition is subjected during storage may have a negative effect on it, resulting in e.g. coalescence, creaming (creaming), syneresis (syneresis), coagulation and/or phase separation. Such compositions therefore become unsuitable for use. The presence of the alkaline salt and the high pH also makes the epilatory composition prone to phase separation, especially at high temperatures. There remains a need for epilatory compositions that are storage stable (also referred to herein as stable upon storage). In particular, there remains a need for epilatory compositions that are stable upon storage when exposed to high temperatures up to 50 ℃ (e.g., temperatures in the range of above freezing up to 50 ℃), and that exhibit, for example, good pH stability, do not phase separate upon storage and/or maintain acceptable viscosity. It is also desirable to provide depilatory compositions that do not thicken unacceptably during production, as this can lead to production and processing difficulties. It is also desirable to provide depilatory compositions that do not thicken unacceptably during storage at the temperatures described above, as this may result in difficulties in applying the composition to the skin, and/or in decanting the composition from its packaging. It is an object of the present invention to provide a depilatory composition comprising a depilatory agent, which addresses one or more of the above-mentioned disadvantages. It is a further object of the present invention to provide a storage stable epilatory composition. It is a particular object to provide epilatory compositions that exhibit good pH stability, do not undergo phase separation, maintain an acceptable viscosity and/or do not thicken unacceptably during production or during storage (e.g. at the temperatures mentioned above). It is a further object of the present invention to provide depilatory compositions which are stable for more than one week when stored at temperatures in the range of from above freezing to up to 50 ℃. It is a further object of the present invention to provide a shelf stable epilatory composition that exhibits good hair removal properties over a contact time of less than 10 minutes. Surprisingly, it has been found that one or more of the above disadvantages can be solved by including a C 1-C20 alkyl hydroxyalkyl cellulose, in particular cetyl hydroxyethyl cellulose, in a depilatory composition comprising a depilatory agent, and the pH of the composition at 30 ℃ is from 10 to 12.9. EP2355788 A2 discloses a depilatory composition comprising a depilatory agent, an emollient selected from at least one of mineral oil, silicone oil, an alkalinity source and water. No examples of depilatory compositions comprising C 1-C20 alkyl hydroxyalkyl cellulose are given. EP3348250 A1 discloses a depilatory cream composition comprising a depilatory agent, an emollient selected from at least one of mineral oil, silicone oil and emollient esters, and a silicone wax, talc and/or polyamide resin. No examples of depilatory compositions comprising C 1-C20 alkyl hydroxyalkyl cellulose are given. Disclosure of Invention In a first aspect, the present invention provides a depilatory composition comprising: (a) The natural oil is used as the natural oil, (B) An alkaline source is provided, which is a source of alkalinity, (C) The depilatory agent is used for the hair, (D) Water, and (E) C 1-C20 alkyl hydroxyalkyl cellulose, and The composition has a pH in the range of 10 to 12.9 measured as a 10% w/v aqueous solution at 30 ℃ plus or minus 0.5 ℃ or as a neat composition. It has been found that the depilatory composition of the present invention remains stable for at least one week, in particular at least two weeks, for example 5 or 6 weeks, when stored at elevated temperatures up to 5