Cleansing oil

Abstract

To provide a cleansing oil in an oil-based formulation with high cleansing capability, which offers bactericidal effects and superior stability at low temperatures.SOLUTION: A cleansing oil contains a following component (B) in which a following (A) component is dissolved, and the following component (C). Preferably, it further contains a following component (D). (A) Isopropylmethylphenol. (B) PEG-20 glyceryl triisostearate. (C) Oil that is liquid at 25°C. (D) Tartaric acid.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a cleansing oil, and more particularly to a cleansing oil having excellent bactericidal effect and excellent low-temperature stability. [Background technology]

[0002] In recent years, as the spread of infection caused by the so-called novel coronavirus has become more serious, regular use of masks is recommended as a measure to prevent infection. Wearing a mask can cause makeup to come off or make-up to stick to the mask due to moisture and humidity inside the mask, as well as friction between the mask and the skin, so makeup that is hard to remove and lasts for a long time is chosen. On the other hand, the humidity and friction caused by regular mask use can cause acne and rough skin, and many consumers suffer from skin problems.

[0003] In addition, concerns about pores, such as blackheads and open pores, are a permanent concern, especially among young people. Pores become noticeable when pores are clogged with keratin plugs, so neglecting pore care will lead to the proliferation of acne bacteria, which will cause acne. Removing keratin plugs is a cosmetically desirable action, but washing the face with a regular cleanser does not provide sufficient removal. In addition, methods for removing keratin plugs using sheet preparations and packs have been proposed, but the adhesiveness puts a strain on the skin, and the use is complicated, requiring time to dry before peeling off, so a simple method for removing keratin plugs was desired.

[0004] Skin cleansers containing bactericides have the effect of preventing acne, and various types are commercially available. Patent Document 1 proposes a cleansing composition containing a bactericidal component selected from piroctone olamine, triclosan, isopropylmethylphenol, benzalkonium chloride, and trichlorocarbanide, Patent Document 2 proposes a cleansing composition containing a bactericidal component selected from triclosan, isopropylmethylphenol, and parachlorometaxylenol, and Patent Document 3 proposes a cleansing composition containing miconazole, isopropylmethylphenol, and salicylic acid. However, although these all have a high bactericidal effect, their cleansing effect is insufficient.

[0005] In addition, the main form of cleansing cosmetics is oil formulation type with high cleansing power.Patent Document 4 discloses a non-aqueous cleansing agent that contains a specific nonionic surfactant and liquid oil as essential components, and Patent Document 5 discloses a cleansing agent that contains a specific nonionic surfactant, liquid oil, and water as essential components.Since these are based on liquid oil, they have excellent compatibility with oil-containing dirt and have high cleansing effect, but they do not have bactericidal effect. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP2007-146030A [Patent Document 2] JP 2010-168555 A [Patent Document 3] JP 2022-164779 A [Patent Document 4] Japanese Unexamined Patent Publication No. 62-108806 [Patent Document 5] Japanese Patent Application Publication No. 03-161428 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in view of the above circumstances, and its object is to provide an oil with high cleansing power. To provide a cleansing oil having a bactericidal effect and excellent low-temperature stability even in a dosage form. [Means for solving the problem]

[0008] As a result of intensive research conducted to achieve the above-mentioned object, the inventors discovered that the above-mentioned problems could be solved by a cleansing oil containing isopropyl methylphenol as a bactericidal component, and a mixture of PEG-20 glyceryl triisostearate in which said isopropyl methylphenol has been dissolved and liquid oil, thereby completing the present invention.

[0009] That is, the present invention provides [1] The cleansing oil is characterized by containing the following (B) in which the following (A) is dissolved, and the following (C). Preferably, the cleansing oil further contains the following (D). (A) Isopropyl methylphenol (B) PEG-20 glyceryl triisostearate (C) Oil that is liquid at 25°C [2] The cleansing oil according to [1] further contains the following (D): (D)Tartaric acid

[0010] [3] A method for producing a cleansing oil, comprising dissolving the following (A) in the following (B), and then mixing (B) with the following (C): (A) Isopropyl methylphenol (B) PEG-20 glyceryl triisostearate (C) Oil that is liquid at 25°C Effect of the Invention

[0011] According to the present invention, a cleansing oil having a strong cleansing power, a bactericidal effect, and excellent low-temperature stability is provided.Furthermore, the cleansing oil does not require double face washing and has an excellent effect of removing keratin plugs. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The configuration of the present invention will be described in detail below.

[0013] As used herein, "low temperature stability" means that the cleansing oil is stable at 5°C for three months or more without precipitation due to the bactericidal components.

[0014] The configuration of the present invention will be described in detail below.

[0015] <(A) Sterilizing ingredient> The component (A) used in the present invention is a bactericidal component. In the cleansing oil, isopropyl methylphenol is used from the viewpoint of preventing the bactericidal component from precipitating.

[0016] The content of component (A) in the cleansing oil is preferably 0.05 to 2% by mass. If it is 0.05% by mass or more, the bactericidal effect is sufficient, and if it is 2% by mass or less, it does not precipitate in the preparation and has good low-temperature stability.

[0017] <(B) Hydrophilic Surfactant> The component (B) used in the present invention is a hydrophilic surfactant, and is used to improve the rinsability with water after cleansing. In the present invention, PEG-20 glyceryl triisostearate is used. It was found that PEG-20 glyceryl triisostearate is the most suitable solvent for suppressing the precipitation of the component (A). This is because the component (A) is hydrophobic and therefore poorly soluble in water, and is easily dissolved when mixed with the polar component (B) compared to non-polar liquid oil.

[0018] The content of component (B) in the cleansing oil is preferably 5 to 15% by mass. If it is 5% by mass or more, there is no feeling of residual skin remaining after rinsing with water, and there is no need to wash the face with a facial cleanser. On the other hand, if it is 15% by mass or less, there is no feeling of stickiness when rinsing with water.

[0019] The blending ratio of component (A) to component (B) ((B) / (A)) is preferably 3 or more. If it is 3 or more, component (A) dissolves completely in (B), and no precipitation occurs after preparation into a cleansing oil.

[0020] <(C) Liquid oil> The component (C) used in the present invention is a liquid oil at 25°C, a base for oil cleansing, and is blended for the purpose of improving cleansing power. The component (C) may be one that is commonly used in cosmetics, medicines, etc., such as silicone oil, ether oil, hydrocarbons, higher alcohol higher fatty acid esters, animal and vegetable oils and fats, cholesterol fatty acid esters, essential oils, fragrances, etc. These are used alone or in combination of two or more, and preferably contain oils such as mineral oil and triethylhexanoin.

[0021] The content of component (C) in the cleansing oil is preferably 80% by mass or more, in order to obtain sufficient cleansing power.

[0022] <(D)Tartaric acid> The component (D) used in the present invention is tartaric acid. Tartaric acid is a type of organic acid. In the present invention, it is blended for the purpose of dissolving both the sebum and old keratin in the keratin plug.

[0023] The content of component (D) in the cleansing oil is preferably 0.01 to 3.0% by mass, more preferably 0.05 to 2.5%. If it is 0.01% by mass or more, it is effective for removing keratin plugs, and if it is 3.0% by mass or less, it does not cause skin irritation or precipitate at low temperatures.

[0024] In the present invention, it is possible to further blend, as necessary, medicinal agents, moisturizing ingredients, anti-inflammatory agents, bactericides, preservatives, ultraviolet absorbers, antioxidants, organic and inorganic powders, pigments, etc., which are commonly used in cosmetics, pharmaceuticals, etc. Furthermore, solid oils and semi-solid oils can be added within a range that does not impair the effects of the present invention. EXAMPLES

[0025] The present invention will be described below with reference to examples, but evaluation methods will be described first, although the present invention is not limited to these examples.

[0026] <Preparation of cleansing oil> First, component (A) shown in Tables 1 and 2 was dissolved in component (B), and then other components were mixed to obtain a cleansing oil.

[0027] <Evaluation test of bactericidal effect> (1) Test bacteria (Harmful Gram-positive bacteria) Staphylococcus aureus: Staphylococcus aureus ATCC6538 (2) Evaluation method 1. Evaluation sample Cleaning compositions of Examples and Comparative Examples (Test Solutions) 2. Preparation of Bacterial Solution Adjust the initial number of bacteria to 108 / mL. (Bacteria solution) 3. Test Method At 25°C, 1 mL of the bacterial solution was added to 9 mL of the test solution and thoroughly stirred. After 5 minutes, 0.5 mL was sampled and the number of viable bacteria was measured. 4. Evaluation The ratio of the number of surviving bacteria to the initial number of bacteria was calculated as the bactericidal rate (%), and the results were shown according to the following evaluation criteria. Note that, with respect to Staphylococcus aureus, the higher the bactericidal effect, the better.

[0028] (Evaluation criteria) Bactericidal effect ◎: Sterilization rate of 90% or more ○: Sterilization rate: 70% or more but less than 90% △: Sterilization rate is 50% or more but less than 70% ×: Sterilization rate less than 50%

[0029] <Low temperature stability evaluation test> The cleansing cosmetic compositions described in the Examples and Comparative Examples were filled into glass bottles and left to stand at 5° C. for three months, after which the stability over time was evaluated according to the following evaluation criteria.

[0030] (Evaluation criteria) Low temperature stability ◎: Transparent appearance with no precipitates ○: Slightly cloudy, but no precipitate △: Slightly cloudy with some precipitate ×: A large amount of precipitate was observed, or component (A) was not completely dissolved in component (B).

[0031] <Evaluation test of cleansing power (sensory evaluation)> A panel of 10 experts applied a commercially available powder foundation, mascara, and lipstick to their faces, and left them to dry for about 4 hours. Next, they took about 1.2 g of the cleansing cosmetic composition described in the Examples and Comparative Examples, spread it over their entire faces while looking in the mirror, blended it with the makeup, rinsed it off with water, and evaluated it based on the following criteria.

[0032] (Evaluation criteria) Cleansing power 5 points: The makeup was removed very well and I felt that the cleansing effect was sufficient. 4 points: Removes makeup well and has a noticeable cleansing effect. 3 points: The makeup was removed fairly well and I could feel some cleansing effect. 2 points: The makeup didn't come off very well, and I didn't really feel any cleansing effect. 1 point: The makeup was barely removed and I couldn't feel any cleansing effect. If the average score for all panels was 4 points or more, it was marked as ◎, if it was 3 points or more, it was marked as ○, if it was 2 points or more, it was marked as △, and if it was less than 2 points, it was marked as ×.

[0033] <Evaluation test of no need for double cleansing (sensory evaluation)> A panel of 10 experts applied a commercial powder foundation, mascara, and lipstick to the face. Next, about 1.2 g of the cleansing cosmetic composition described in the Examples and Comparative Examples was taken and spread over the entire face while looking in the mirror, blending with the makeup, and then washed off with water. The results were evaluated based on the following criteria.

[0034] (Evaluation criteria) No need for double cleansing 5 points: Not sticky at all, refreshing, no need for double cleansing. 4 points: No sticky feeling, no need for double cleansing. 3 points: Not very sticky but very moist, double cleansing is recommended. 2 points: Sticky feeling remains, so I want to double cleanse. 1 point: Quite sticky, double cleansing is essential. If the average score for all panels was 4 points or more, it was marked as ◎, if it was 3 points or more, it was marked as ○, if it was 2 points or more, it was marked as △, and if it was less than 2 points, it was marked as ×.

[0035] <Evaluation test of keratin plug removal effect> Five healthy panelists took about 1g of the cleansing cosmetic composition described in the Examples and Comparative Examples, applied it only to the nose while looking in the mirror, massaged for 30 seconds, and then rinsed with water for 1 minute. The number of keratin plugs present on the nostrils was counted before and after washing, and the keratin plug removal rate was calculated and evaluated using the following formula (Formula 1). Keratin plug removal rate = 100-(1cm above the nostril after use) 2 Number of keratin plugs present) / (1cm above the nostril before use 2 (Number of keratin plugs present) x 100 (Formula 1)

[0036] (Evaluation criteria) Effect of removing keratin plugs ◎: Corner plug removal rate of 60% or more ○: Keratin plug removal rate: 40% to less than 60% △: Keratin plug removal rate is 20% or more but less than 40% ×: Less than 20% of keratin plugs removed

[0037] <Skin irritation during use> A panel of 20 experts took approximately 3 g of the cleansing cosmetic composition described in the Examples and Comparative Examples, spread it over the entire face while looking in the mirror, then rinsed it off with water and evaluated it based on the following evaluation criteria.

[0038] (Evaluation criteria) Skin irritation during use ◎: 18 or more subjects reported no irritation during use ○: 15-17 subjects reported no irritation during use △: 9-13 subjects reported no irritation during use ×: Fewer than 8 subjects reported no irritation during use.

[0039] Examples 1 to 19, Comparative Examples 1 to 5 Cleansing oils having the compositions shown in Tables 1 and 2 were prepared and evaluated. The results are also shown in Tables 1 and 2. In addition, except for Comparative Example 5, component (A) was first dissolved in component (B), and then mixed with other components including (C) to prepare the cleansing oils. In Comparative Example 5, all components were mixed at the same time.

[0040] [Table 1]

[0041] [Table 2]

[0042] As is clear from Tables 1 and 2, the compositions of Examples 1 to 19 using the components of the present invention all showed excellent performance. On the other hand, the compositions of Comparative Examples 1 to 5 were inferior in any of the properties of bactericidal effect, cleansing power, elimination of need for double face washing, keratin plug removal effect, and skin irritation during use, and the object of the present invention could not be achieved.

[0043] In particular, Comparative Example 2, which used a bactericide different from component (A), Comparative Example 3, which did not use a hydrophilic surfactant, and Comparative Example 5, in which all components were mixed simultaneously, were unable to dissolve the bactericidal component, and the bactericidal effect test was discontinued. In addition, Comparative Example 4, which used a hydrophilic surfactant different from component (B), was able to dissolve the bactericidal component, but precipitates occurred over time and low-temperature stability was poor.

Claims

1. A cleansing oil characterized by containing the following (B) in which the following (A) is dissolved, and the following (C): (A) Isopropyl methylphenol (B) PEG-20 glyceryl triisostearate (C) Oil that is liquid at 25°C

2. 2. The cleansing oil according to claim 1, further comprising the following (D): (D) Tartaric acid

3. A method for producing a cleansing oil, comprising dissolving the following (A) in the following (B), and then mixing (B) with the following (C). (A) Isopropyl methylphenol (B) PEG-20 glyceryl triisostearate (C) Oil that is liquid at 25°C

Images