JP7690276B2 - Oil-based cleansing cosmetic composition - Google Patents

Description

The present invention relates to an oil-based cleansing cosmetic composition that contains a specific polyglycerol fatty acid ester and a hydrocarbon oil, and to a cosmetic that contains this oil-based cleansing cosmetic composition.

There are many different types of cleansing cosmetics for removing makeup, but the mainstream is the oil type, which is highly effective at removing makeup and can be easily washed off. In addition, since they are often used while bathing, there is a demand for them to have cleansing power that does not decrease even when used with wet hands.

When liquid paraffin and other hydrocarbon oils are blended into cleansing oils, it is possible to achieve a thick application sensation that cannot be achieved with ester oils. Cleansing oils blended with polyglycerol medium-chain fatty acid esters (see, for example, Patent Document 1) are examples of cleansing cosmetics that can be used with wet hands, but the amount of hydrocarbon oil blended is limited. If the amount of hydrocarbon oil blended is increased beyond this amount, there is a problem that the storage stability at low temperatures is poor and separation occurs.
Also, a hydrocarbon oil composition that is excellent in transparency and stability over time has been provided by using an ester of polyglycerin and an unsaturated or branched fatty acid having 18 carbon atoms (see, for example, Patent Document 2). However, this hydrocarbon oil composition gels when mixed with water, and has problems in that it feels bad when applied to the skin when used with wet hands and does not provide a refreshing feeling when washed off.

JP 2005-162691 A JP 2013-49011 A

The object of the present invention is to provide a composition containing a hydrocarbon oil and having high low-temperature storage stability, and a cosmetic containing the same, which can be used with wet hands and can provide a thick application sensation that cannot be obtained with commonly used ester oils, and a cosmetic containing the oil-based cleansing cosmetic composition.

As a result of the intensive efforts of the inventors to solve the above problems, they discovered that by combining two or more specific types of polyglycerol fatty acid esters, it is possible to stably contain a hydrocarbon oil in a cleansing cosmetic, and thus completed the present invention.

The oil-based cleansing cosmetic composition of the present invention, and a cleansing cosmetic containing this oil-based cleansing cosmetic composition, contain sufficient hydrocarbon oil to provide a thick application feel, and are highly stable when stored at low temperatures without separation or turbidity. The oil-based cleansing cosmetic composition of the present invention, and a cleansing cosmetic containing this oil-based cleansing cosmetic composition, are thick when applied, have a small emulsion particle size when washed off, and provide a refreshing, non-sticky feel. Furthermore, a moist feel can be provided after washing off.

The present invention will be described in detail below.
The oil-based cleansing cosmetic composition of the present invention contains two or more specific polyglycerol fatty acid esters as components (A) and (B), and a hydrocarbon oil as component (C).

The polyglycerol fatty acid ester of component (A) in the present invention is an ester of a fatty acid having 8 to 10 carbon atoms and a polyglycerol having an average degree of polymerization of 5 to 14, more preferably 6 to 10, and has an HLB of 9 to 11. Component (A) is not particularly limited, but examples thereof include at least one selected from the group consisting of hexaglyceryl dicaprate, hexaglyceryl tricaprylate, decaglyceryl pentacaprylate, decaglyceryl hexacaprylate, etc.

The polyglycerol fatty acid ester of component (B) in the present invention is a diester of polyglycerol and an unsaturated and/or branched fatty acid having 18 carbon atoms. If the constituent fatty acid is a straight-chain saturated fatty acid, it will crystallize during low-temperature storage in the oil-based cleansing cosmetic composition, resulting in poor low-temperature storage stability. Component (B) is not particularly limited, but examples thereof include at least one selected from the group consisting of decaglyceryl dioleate, hexaglyceryl dioleate, decaglyceryl diisostearate, etc.

The average degree of polymerization of the polyglycerol constituting the polyglycerol fatty acid ester of components (A) and (B) in the present invention is calculated from the hydroxyl value based on the following formula: The hydroxyl value was measured by a known method.
OHV=56110(n+2)/(74n+18)
OHV: hydroxyl value of polyglycerol n: average degree of polymerization of polyglycerol

The polyglycerol fatty acid esters of components (A) and (B) in the present invention can be easily obtained by esterifying polyglycerol with a fatty acid by a conventional method or by addition polymerization of a fatty acid with glycidol. The esterification of polyglycerol with a fatty acid is not particularly limited, but can be carried out, for example, by heating polyglycerol with a fatty acid in the presence of an acid catalyst (phosphoric acid, p-toluenesulfonic acid, etc.) or an alkali catalyst (caustic soda, etc.), or without a catalyst, preferably at 100 to 300°C, more preferably at 120 to 260°C while removing water. The reaction may also be carried out in the presence of an inert gas. The esters thus obtained may be purified according to the purpose. In addition to distillation techniques such as distillation under reduced pressure, molecular distillation, and steam distillation, extraction with an organic solvent, fractionation, and chromatographic separation using a column filled with a synthetic adsorbent or gel filtration agent can also be used for purification. The desired polyglycerol fatty acid ester may be obtained by using an ester of a fatty acid instead of a fatty acid and carrying out ester exchange with polyglycerol.

In the present invention, the HLB refers to a value measured by the following calculation method. The saponification value and neutralization value were measured by known methods.
HLB=20(1-S/A)
S: Saponification value of polyglycerol fatty acid ester A: Neutralization value of raw material fatty acid

The content of the polyglycerol fatty acid ester of component (A) in the oil-based cleansing cosmetic composition of the present invention is preferably 3 to 10 mass %, more preferably 5 to 10 mass %.

The content of the polyglycerol fatty acid ester of component (B) in the oil-based cleansing cosmetic composition of the present invention is preferably 5 to 15 mass %, more preferably 10 to 15 mass %.

The mass ratio of the polyglycerol fatty acid esters of components (A) and (B) in the oil-based cleansing cosmetic composition of the present invention is 1:1 to 1:3.

The hydrocarbon oil of component (C) in the present invention is not particularly limited, but examples thereof include at least one selected from the group consisting of hydrogenated polyisobutene, liquid paraffin, light liquid isoparaffin, squalane, isododecane, alkanes, etc., and from the viewpoint of moisturizing feeling after washing, liquid paraffin is preferred.

The content of the hydrocarbon oil of component (C) in the oil-based cleansing cosmetic composition of the present invention is preferably 20% by mass or more, more preferably 40% by mass or more, and even more preferably 60% by mass or more, from the viewpoint of moist feeling after cleansing. When two or more types of hydrocarbon oil of component (C) are used, the content refers to the total amount.

The oil-based cleansing cosmetic composition of the present invention can contain ingredients that are normally used in cosmetics, as appropriate, depending on the application and purpose, so long as the effects of the present invention are not impaired. Examples of ingredients that can be included, but are not limited to, include surfactants other than the polyglycerol fatty acid esters of components (A) and (B), oils other than the hydrocarbon oils of component (C), aqueous gelling agents, oil-based gelling agents, UV absorbers, powders, antioxidants, preservatives, fragrances, colorants, chelating agents, cooling agents, thickeners, plant extracts, vitamins, neutralizing agents, moisturizing agents, anti-inflammatory agents, pH adjusters, amino acids, etc.

The method for preparing the oil-based cleansing cosmetic composition of the present invention is not particularly limited, but it can be prepared, for example, by dissolving all the ingredients at 60°C or higher and then cooling to room temperature.

The oil-based cleansing cosmetic composition of the present invention preferably has a transparent appearance, and when used in an oil-based cleansing cosmetic, it provides a thick application feeling and can be washed off cleanly. The cleansing cosmetic of the present invention is preferably an oil-based cleansing cosmetic that can be used even with wet hands.

The content of the oil-based cleansing cosmetic composition in the cleansing cosmetic of the present invention is preferably 30 to 100% by mass, more preferably 50 to 100% by mass, and even more preferably 80 to 100% by mass, from the viewpoint of cleansing power.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" means "% by mass."

Preparation of oil-based cleansing cosmetic compositions Examples 1 to 16 and Comparative Examples 1 to 8
Each component was dissolved at 80°C in a 200 ml beaker in the amounts shown in Tables 1 to 3, and then cooled to room temperature with stirring to prepare 100 g of oil-based cleansing cosmetic compositions of the present invention products 1 to 16 and comparative products 1 to 8. Each polyglycerol fatty acid ester was synthesized by a known method.

The oil-based cleansing cosmetic compositions of the present invention products 1 to 16 and comparison products 1 to 8 were evaluated according to the following criteria for appearance, low-temperature storage stability, water resistance, emulsion particle size, refreshing feeling during cleansing, and moist feeling after cleansing. The results are shown in Tables 1 to 3.

(Test Example 1: Appearance)
Immediately after preparation, 10 g of the oil-based cleansing cosmetic compositions of the present invention Products 1 to 16 and the comparative products 1 to 8 were placed in a vial (volume 20 ml, inner diameter 2.5 cm) and the appearance properties were visually observed according to the following evaluation criteria.

(Evaluation Criteria)
◯: No turbidity or separation is observed △: Slight turbidity is observed ×: Separation is observed

(Test Example 2: Low temperature storage stability)
10 g of each of the oil-based cleansing cosmetic compositions of Invention Products 1 to 16 and Comparative Products 1 to 8 was placed in a vial (volume 20 ml, inner diameter 2.5 cm) and stored at 5° C. for 1 day. The appearance properties were then visually observed according to the following evaluation criteria.

(Evaluation Criteria)
◯: No turbidity or separation is observed △: Slight turbidity is observed ×: Separation is observed

(Test Example 3: Water Resistance Test)
Assuming use with wet hands containing a large amount of water, 20 g of each of the oil-based cleansing cosmetic compositions of the present invention products 1 to 16 and the comparative products 1 to 8 were placed in a vial (volume 50 ml, inner diameter 3.2 cm) and stirred while adding water little by little to prepare a sample. The limiting water content at which the sample remained visually stable and transparent was calculated using the following formula.
Critical hydration rate (%) = E/20 x 100
E: Amount of water added (g)

(Test Example 4: Emulsion particle size)
1 g of each of the oil-based cleansing cosmetic compositions of the present invention products 1 to 16 and the comparative products 1 to 8 was placed in a vial (volume 100 ml, inner diameter 3.2 cm). After adding 99 g of water and mixing, the particle size distribution was measured using a particle size distribution meter (BECKMAN COULTER LS 13 320). The average diameter was taken as the emulsion particle size.

(Test Example 5: Refreshing feeling when washing)
Each of the oil-based cleansing cosmetic compositions of the present invention products 1 to 16 and the comparative products 1 to 8 was applied in an amount of 1 g to the face, massaged for 30 seconds, and then washed off with water. The refreshing feeling after cleansing was evaluated on a three-point scale according to the following evaluation criteria.

(Evaluation Criteria)
〇: Washes off cleanly △: Leaves a slight sticky feeling ×: Not refreshing, leaves a sticky feeling

(Test Example 6: Moisturizing Feeling After Washing)
Each of the oil-based cleansing cosmetic compositions of the present invention products 1 to 16 and the comparative products 1 to 8 was applied in an amount of 1 g to the face, massaged for 30 seconds, and then washed off with water. After wiping off the water with a towel, the moist feeling after washing was evaluated on a three-point scale according to the following evaluation criteria.

(Evaluation Criteria)
◯: Moist △: Slightly moist ×: Not moist

As is clear from the results in Tables 1 to 3, the oil-based cleansing cosmetic compositions of the present invention, Products 1 to 16, all had excellent appearance properties, low-temperature storage stability, and water resistance, and provided a refreshing feeling during washing and a moist feeling after washing. Comparative Products 1 and 7, which did not contain the polyglycerin fatty acid ester of components (A) and (B), and Comparative Product 2, which used the polyglycerin fatty acid ester of components (A) and (B) but had a mass ratio outside the range of 1:1 to 1:3, gelled when water was added, and had impaired washability. Comparative Products 3 and 4, which had a mass ratio of the polyglycerin fatty acid ester of components (A) and (B) outside the range of 1:1 to 1:3, and Comparative Products 5 and 6, which had an HLB of the polyglycerin fatty acid ester of component (A) outside the range of 10 to 12, had insufficient low-temperature storage stability and water resistance. Comparative Product 8, which did not contain the hydrocarbon oil of component (C), did not have a thick coating when applied and did not provide a moist feeling after washing.

Below is a formulation example of the cleansing cosmetic of the present invention. The present invention is not limited to this formulation example in any way. All contents are expressed as mass % of the total product. This formulation example contains various ingredients normally used in cosmetics in an oil-based cleansing cosmetic composition, as appropriate for the application and purpose, and was prepared by heating and dissolving all ingredients at 80°C, and then cooling to room temperature while stirring.

Formulation Example 1 (Cleansing Oil)
Using invention product 4, a cleansing oil containing the invention product was prepared according to the recipe shown in Table 4. The appearance, low-temperature storage stability, and water resistance were satisfactory, and the usability, such as a refreshing feeling during cleansing and a moist feeling after cleansing, was good.

Formulation example 2 (cleansing oil gel)
A cleansing oil gel containing the product of the present invention was prepared using product 5 according to the recipe shown in Table 5. The appearance, low-temperature storage stability, and water resistance were satisfactory, and the usability, such as a refreshing feeling during cleansing and a moist feeling after cleansing, was good.

The oil-based cleansing cosmetic composition of the present invention has high low-temperature storage stability, and when used in a cleansing cosmetic, it rinses off cleanly during cleansing while maintaining high low-temperature storage stability, and leaves a moist feel after cleansing. This makes it possible to provide an oil-based cleansing cosmetic that can be used in cleansing cosmetics, and in particular, can be used with wet hands, making a great contribution to the industry.

Claims (4)

An oil-based cleansing cosmetic composition containing the following components (A) to (C), but not containing hydrogenated palm kernel oil, wherein the content of component (A) in the composition is 3 to 10 mass%, the content of component (B) is 5 to 15 mass%, and the content of component (C) is 20 to 92 mass%, and the mass ratio of component (A) to component (B) is 1:1 to 1:3.
(A) A polyglycerol fatty acid ester, which is an ester of a fatty acid having 8 to 10 carbon atoms and a polyglycerol having an average degree of polymerization of 5 to 14, and has an HLB of 9 to 11. (B) A polyglycerol fatty acid ester, which is a diester of an unsaturated and/or branched fatty acid having 18 carbon atoms and a polyglycerol. (C) A hydrocarbon oil. The oil-based cleansing cosmetic composition according to claim 1, wherein the polyglycerol fatty acid ester of component (A) is at least one selected from the group consisting of hexaglyceryl dicaprylate, hexaglyceryl tricaprylate, decaglyceryl pentacaprylate, and decaglyceryl hexacaprylate. The oil-based cleansing cosmetic composition according to claim 1 or 2, wherein the polyglycerol fatty acid ester of component (B) is at least one selected from the group consisting of decaglyceryl dioleate, hexaglyceryl dioleate, and decaglyceryl diisostearate. A cleansing cosmetic comprising the oil-based cleansing cosmetic composition according to any one of claims 1 to 3.