Solubilizing agent and cosmetic containing same

Abstract

The present invention addresses the problem of providing: a solubilizing agent that uses a specific polyglycerol fatty acid ester and that makes it possible to obtain a solubilizing composition in which, even when a large amount of an oil-soluble substance is contained, the oil-soluble substance is finely dispersed in an aqueous phase without the use of a special emulsification machine or the like, which has excellent stability over time, and which has high transparency; and a cosmetic that uses the solubilizing agent. Provided is a solubilizing agent comprising: a polyglycerol fatty acid ester (A) which is esterified with a C10-14 unsaturated fatty acid, in which the average degree (n) of polymerization calculated from the hydroxyl value of a polyglycerol is 8-32, and which has an esterification rate of less than 7.3%; and / or a polyglycerol fatty acid ester (B) which is esterified with a C10-14 unsaturated fatty acid, in which the average degree (n) of polymerization calculated from the hydroxyl value of a polyglycerol is not less than 4 but less than 8, and which has an esterification rate of not more than 11%. Also provided is a cosmetic that uses the solubilizing agent.

Description

Solubilizer and cosmetic containing same

[0001] The present invention relates to a solubilizer for oil-soluble substances. More specifically, the present invention relates to a solubilizer based on a specific polyglycerol fatty acid ester that can easily solubilize oil-soluble substances in cosmetics, and to cosmetics utilizing this solubilizer.

[0002] The process of incorporating an oil-soluble substance that is insoluble in water into micelles or liquid crystals in the presence of water and a surfactant to prepare a transparent solution is called solubilization, and surfactants used for this purpose are called solubilizers. Solubilizers are widely used in foods, pharmaceuticals, cosmetics, etc. Solubilized compositions differ from emulsions, which are obtained by adding a surfactant to an aqueous phase and an oil phase and stirring them, in that they are thermodynamically stable and have high stability over time.

[0003] Conventionally, nonionic surfactants have been mainly used as solubilizers, and polyoxyethylene surfactants in particular have been used. However, polyoxyethylene surfactants may cause problems such as residual ethylene glycol and skin irritation due to the residual ethylene glycol, and therefore, there is a demand for safer, less skin irritating, and highly hydrophilic solubilizers.

[0004] On the other hand, polyglycerol fatty acid esters are highly safe and are therefore used as emulsifiers and solubilizers for food, pharmaceutical, or cosmetic products, and various methods for solubilizing oil-soluble substances using polyglycerol fatty acid esters have been investigated.

[0005] Patent Document 1 discloses a method for solubilizing an oil-soluble substance using a mixture of polyglycerol laurate and polyglycerol condensed ricinoleate. Patent Document 2 discloses a method for solubilizing an oil-soluble substance using a polyglycerol saturated fatty acid ester. Patent Document 3 discloses a method for solubilizing an oil-soluble substance using a polyglycerol fatty acid ester obtained by esterification with a mixed fatty acid of saturated fatty acid and unsaturated fatty acid.

[0006] Patent No. 3534199 Patent No. 3528382 Patent No. 5179744

[0007] The method described in Patent Document 1 makes it difficult to obtain a stable solubilized composition with sufficient transparency when a large amount of an oil-soluble substance is blended. The method disclosed in Patent Document 2 requires a homogenization treatment using a special emulsifier such as an ultra-high pressure homogenizer, which is problematic in that the operation is very cumbersome and lacks practicality. Furthermore, the method described in Patent Document 3 requires the addition of a polyglycerol condensed ricinoleic acid ester to obtain a highly transparent solubilized composition, and solubilization of highly polar essential oils and fragrances is particularly difficult. Another problem is the necessity of mixing an unsaturated fatty acid, which may cause coloration or an oxidized odor in terms of stability over time.

[0008] An object of the present invention is to provide a solubilizer that can produce a solubilized composition that is stable over time and highly transparent, even when a relatively large amount of oil-soluble substances is blended. Another object of the present invention is to provide a solubilizer that can produce a solubilized composition without requiring complicated operations such as the use of a special emulsifier. A further object of the present invention is to provide a cosmetic that is highly transparent and stable over time by utilizing this solubilizer.

[0009] As a result of extensive research, the present inventors have found that an excellent solubilizing effect is exhibited in a polyglycerol fatty acid ester (component (A)) obtained using a saturated fatty acid having 10 to 14 carbon atoms, the polyglycerol having an average degree of polymerization (n) of 8 to 32 calculated from the hydroxyl value of the polyglycerol and an esterification rate of less than 7.3%, and / or a polyglycerol fatty acid ester (component (B)) having an average degree of polymerization (n) of 4 or more but less than 8 calculated from the hydroxyl value of the polyglycerol and an esterification rate of 11% or less. The use of this solubilizing agent has enabled the production of a solubilized composition with excellent stability over time and high transparency, leading to the completion of the present invention.

[0010] One embodiment of the present invention is a solubilizing agent containing the following component (A) and / or component (B): (A) a polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 8 to 32 calculated from the hydroxyl value of the polyglycerol and an esterification rate of less than 7.3%, and (B) a polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 4 or more but less than 8 calculated from the hydroxyl value of the polyglycerol and an esterification rate of 11% or less.

[0011] Hereinafter, component (A) may be referred to as polyglycerol fatty acid ester (A), and component (B) may be referred to as polyglycerol fatty acid ester (B).

[0012] By using the polyglycerol fatty acid ester of this embodiment as a solubilizing agent, oil-soluble substances can be easily solubilized without the need for special emulsifying equipment, even when a high content of oil-soluble substances is incorporated. In the present application, it has been discovered that the use of a fatty acid having an esterification rate not exceeding a specific level, a degree of glycerol polymerization within a specific range, and a specific number of carbon atoms enhances the ability to solubilize oil-soluble substances in water and maintains this solubilization ability (it has been discovered that the combination of these three elements improves the ability to solubilize in water). Furthermore, a solubilized composition in which an oil-soluble substance is solubilized by the solubilizing agent of the present invention not only achieves a highly transparent appearance, but also exhibits excellent stability over time at various temperatures, including room temperature, −5°C, 5°C, and 45°C, and cycles (−5°C → 25°C → 45°C → 25°C = 1 cycle, with each temperature being left standing for 6 hours).

[0013] The present invention also encompasses the use of the polyglycerol fatty acid ester (A) and / or the polyglycerol fatty acid ester (B) as a solubilizing agent.

[0014] Hereinafter, embodiments for carrying out the present invention will be described in more detail, but the scope of the present invention is not limited to these embodiments. In this specification, the range "X to Y" includes X and Y and means "X or more and Y or less." Unless otherwise specified, operations and measurements of physical properties, etc. are carried out under conditions of room temperature (20 to 25°C) and a relative humidity of 40 to 55% RH.

[0015] In both cases, the polyglycerol fatty acid ester (A) and polyglycerol fatty acid ester (B), which are solubilizers of the present invention, contain a constituent fatty acid selected from saturated fatty acids having 10 to 14 carbon atoms. That is, the polyglycerol fatty acid ester (A) / polyglycerol fatty acid ester (B) are fatty acid esters of polyglycerol and at least one fatty acid selected from saturated fatty acids having 10 to 14 carbon atoms. The presence of such constituent fatty acids significantly improves solubility at a specific or lower esterification rate and a specific range of glycerol polymerization degree. The saturated fatty acid may be linear or branched, but linear fatty acids are preferred because they further improve solubility. Examples of saturated fatty acids having 10 to 14 carbon atoms include capric acid, undecylic acid, lauric acid, and myristic acid. These saturated fatty acids may be used alone or in combination. A preferred embodiment is a polyglycerol fatty acid ester composed of a single fatty acid. In either case, the polyglycerol fatty acid ester (A) or the polyglycerol fatty acid ester (B) preferably contains at least one constituent fatty acid selected from saturated fatty acids having 12 to 14 carbon atoms, and more preferably lauric acid and / or myristic acid, because this is more effective in solubilizing oily components with small molecular weights, such as essential oils and fragrances.

[0016] The polyglycerol fatty acid ester (A) of the present invention preferably has an esterification rate of less than 7.3%, and the polyglycerol fatty acid ester (B) of the present invention preferably has an esterification rate of 11% or less. If the esterification rate is higher than these values, the polyglycerol fatty acid ester (A) does not exhibit excellent solubilizing performance.

[0017] Here, the esterification rate is a value calculated by (Equation 2) from the average degree of polymerization (n) of polyglycerol calculated by (Equation 1) below and the number of moles of fatty acid charged relative to polyglycerol (M). The average degree of polymerization (n) of polyglycerol can be calculated to two decimal places by rounding off to two decimal places. The esterification rate can be calculated to one decimal place by rounding off to one decimal place.

[0018] (Formula 1) n = (112,220 - 18 x hydroxyl value) / (74 x hydroxyl value - 56,110) (Formula 2) (M / (n + 2)) x 100 = esterification rate (%) The hydroxyl value in (Formula 1) is a numerical value that indicates the number of hydroxyl groups in polyglycerol, and refers to the number of milligrams of potassium hydroxide required to neutralize the acetic acid required to acetylate the free hydroxyl groups contained in 1 g of polyglycerol. The number of milligrams of potassium hydroxide is calculated in accordance with "Standard Test Methods for the Analysis of Fats, Oils and Related Compounds (I), 2003 Edition, Established by the Japan Oil Chemists' Society," compiled by the Japan Oil Chemists' Society.

[0019] The lower limit of the esterification rate of the polyglycerol fatty acid ester (A) is preferably 0.5% or more, 1% or more, 1.5% or more, or 2% or more from the viewpoint of the stability of the solubilized solution. The upper limit of the esterification rate of the polyglycerol fatty acid ester (A) is preferably 7% or less, or less than 7%, from the viewpoint of solubility. From the viewpoint of solubilization performance, the esterification rate of the polyglycerol fatty acid ester (A) is preferably 0.5% or more but less than 7.3%, more preferably 1 to 7%, even more preferably 1.5 to 7%, even more preferably 2 to 7%, and particularly preferably 2% or more but less than 7%. The average degree of polymerization (n) of the polyglycerol fatty acid ester (A) is 8 to 32, preferably 10 to 32, more preferably 12 to 32, and even more preferably 15 to 32. The polyglycerol fatty acid ester (A) may be used alone or in combination of two or more types.

[0020] From the viewpoint of the stability of the solubilized solution, the lower limit of the esterification rate of the polyglycerol fatty acid ester (B) is preferably 0.5% or more, 1% or more, 1.5% or more, 2% or more, 3% or more, 4% or more, 5% or more, or 6% or more. From the viewpoint of solubilization performance, the esterification rate of the polyglycerol fatty acid ester (B) is preferably 0.5 to 11%, more preferably 1 to 11%, even more preferably 1.5 to 11%, even more preferably 2 to 11%, and preferably 3 to 11%, 4 to 11%, 5 to 11%, or 6 to 11%. The average degree of polymerization (n) of the polyglycerol fatty acid ester (B) is 4 or more and less than 8, preferably 4 to 7, and may be 5 to 7. The polyglycerol fatty acid ester (B) may be used alone or in combination of two or more.

[0021] The esterification rate of the polyglycerol fatty acid ester can be adjusted, for example, by adjusting the molar ratio of the fatty acid to the polyglycerol.

[0022] The preparation method (solubilization method) for using the solubilizer of the present invention is not particularly limited. Examples include mixing the solubilizer with an oil-soluble substance and adding the mixture to an aqueous phase. Alternatively, the solubilizer and oil-soluble substance can be added directly to the aqueous phase. A highly transparent solubilized composition can be obtained by stirring the aqueous phase to which the mixture of the solubilizer and oil-soluble substance has been added. In either case, it is preferable to first blend the solubilizer with a polyhydric alcohol (which may be added separately from the polyhydric alcohol contained in the solubilizer described below) before adding it, as this increases the fluidity of the solubilizer and improves handling during production. The polyhydric alcohol used in this case is not particularly limited, but is preferably one having 2 to 10 carbon atoms, more preferably one having 3 to 8 carbon atoms, and particularly preferably one having 3 to 6 carbon atoms. Examples of such polyhydric alcohols include 1,3-butylene glycol, propylene glycol, dipropylene glycol, pentylene glycol, propanediol, hexanediol, octanediol, glycerin, and diglycerin. These polyhydric alcohols may be used alone or in combination of two or more. The amount (mass) of the polyhydric alcohol added is preferably 0 to 20.0 parts by weight per 1 part of the solubilizing agent (or the total amount when two or more types are used).

[0023] When solubilizing an oil-soluble substance using a solubilizing agent, various stirring means may be used. The solubilizing agent of the present invention has high solubilizing ability, and the stirring method is not particularly limited, but since it does not require a high mechanical shear force (for example, an ultra-high pressure homogenizer), known stirring means such as a magnetic stirrer (for example, a hot stirrer), a paddle mixer, a propeller mixer, or a planetary mixer can be used.

[0024] The solubilizer of the present invention has the ability to solubilize an oil-soluble substance. Specifically, for example, a solution prepared by dissolving 0.3 parts by mass of an oil-soluble substance, such as a fragrance or essential oil (e.g., jasmine oil), and 1.8 parts by mass of the solubilizer in 100 parts by mass of water has a transmittance at 680 nm of preferably 70% or more, more preferably 80% or more.

[0025] The solubilizing agent of the present invention may consist solely of component (A) and / or component (B). The solubilizing agent of the present invention may also contain water, a polyhydric alcohol, a preservative, a pH buffer, etc.

[0026] Examples of polyhydric alcohols include propylene glycol, 1,3-butylene glycol, dipropylene glycol, pentylene glycol, hexylene glycol, propanediol, 1,2-hexanediol, and glycerin. The polyhydric alcohols may be used alone or in combination of two or more. Examples of preservatives include parabenzoic acid esters such as methyl parahydroxybenzoate, sodium benzoate, phenoxyethanol, and sodium dehydroacetate. The preservatives may be used alone or in combination of two or more.

[0027] The specific amount of the polyhydric alcohol or preservative added may be, for example, 50% by mass or less, or 40% by mass or less, more preferably 30% by mass or less, and may be 20% by mass or less, 15% by mass or less, 5% by mass or less, or 1% by mass or less, relative to the total mass (100% by mass) of the solubilizer. It is particularly preferred that the solubilizer contains a polyhydric alcohol such as propylene glycol, 1,3-butylene glycol, dipropylene glycol, pentylene glycol, hexylene glycol, propanediol, 1,2-hexanediol, or glycerin, and it is particularly preferred that the solubilizer contains at least one selected from the group consisting of 1,3-butylene glycol, dipropylene glycol, pentylene glycol, 1,2-hexanediol, and glycerin, and it is particularly preferred that the solubilizer contains at least one selected from the group consisting of 1,3-butylene glycol, pentylene glycol, 1,2-hexanediol, and glycerin. The above polyhydric alcohols are often used in cosmetics as moisturizing agents, but because they have antibacterial properties, they also act as preservatives.

[0028] Examples of pH buffers include lactic acid-sodium lactate, citric acid-sodium citrate, and succinic acid-sodium succinate. One pH buffer may be used alone, or two or more may be used in combination. The specific amount of the pH buffers added may be, for example, 1% by mass or less, or 0.5% by mass or less in total, relative to the total mass (100% by mass) of the solubilizing agent.

[0029] The solubilizing agent of the present invention can be used to solubilize any oil-soluble substance. Examples of oil-soluble substances include vegetable oils, animal oils, and mixtures thereof. Examples of vegetable oils include olive oil, jojoba oil, castor oil, meadowfoam seed oil, wheat germ oil, rice bran oil, safflower oil, soybean oil, corn oil, rapeseed oil, palm oil, sunflower oil, cottonseed oil, coconut oil, peanut oil, camellia oil, cocoa oil, and various triacylglycerols. Examples of animal oils include beef tallow, chicken fat, lard, mutton tallow, mackerel oil, cod oil, and whale oil. Further examples of oil-soluble substances that can be solubilized by the solubilizing agent of the present invention include colorants, essential oils, flavorings, fat-soluble vitamins, fat-soluble drugs, antioxidants, preservatives, saturated or unsaturated higher alcohols, hydrocarbon oils, and polar oils.

[0030] In particular, the solubilizer of the present invention can be used to solubilize essential oils and / or fragrances. When essential oils and oil-based fragrances are used, the total content of the essential oils and / or oil-based fragrances in the solubilized composition (or cosmetic) is preferably 0.001 to 10% by mass, or may be 0.01 to 5% by mass, 0.1 to 3% by mass, or 0.5 to 3% by mass, relative to the total amount of the solubilized composition (or cosmetic) (100% by mass). The essential oils and fragrances may be used alone or in combination of two or more.

[0031] Examples of coloring agents include cocoa pigment, β-carotene, paprika pigment, annatto pigment, safflor yellow, riboflavin, lac pigment, curcumin, chlorophyll, turmeric pigment, etc. Examples of essential oils and fragrances include orange oil, lemon oil, lime oil, peppermint oil, spearmint oil, clove oil, ginger oil, peppermint oil, sage oil, rose oil, rosemary oil, geranium oil, cedarwood oil, sandalwood oil, lavender oil, eucalyptus oil, yuzu oil, lemongrass, ylang-ylang, tea tree, frankincense, labdanum, vanilla, tonka bean, musk, pinene, terpinene, thujone, linalool, linalyl acetate, and limonene. , citral, citronellol, nerol, farnesol, eugenol, geraniol, cineole, octanal, decanal, phenethyl alcohol, myrcene, nootkatone, cinnamic aldehyde, camphor, camphene, phellandrene, curcumene, caryophyllene, benzyl acetate, benzyl benzoate, phytol, sandera, ionone, isoe super, isobutylquinoline, borneol, menthol, menthone, pulegone, etc.

[0032] Examples of fat-soluble vitamins and fat-soluble drugs include vitamin A, vitamin D, vitamin E, vitamin K, or esters of these vitamins with acetic acid, butyric acid, nicotinic acid, palmitic acid, etc., β-carotene, CoQ10 (ubidecarenone), antibiotics such as erythromycin and xanthamycin, γ-oryzanol, etc. Examples of antioxidants include mixed tocopherols, dimethylhydroxytoluene, butylhydroxyanisole, pyridoxine isopalmitate, ascorbic acid stearate, ascorbic acid isopalmitate, γ-oryzanol, catechins, etc.

[0033] Examples of preservatives include dehydroacetic acid and monoglycerin medium-chain fatty acid esters. Examples of saturated or unsaturated higher alcohols include lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, oleyl alcohol, isostearyl alcohol, and 2-octyldodecanol octacosanol. Examples of hydrocarbon oils include liquid paraffin, liquid isoparaffin, isododecane, isohexadecane, ceresin, paraffin, microcrystalline wax, petrolatum, squalane, hydrogenated farnesene, and squalene. Examples of polar oils include octinoxate, oxybenzone, dimethyl PABA octyl, t-butyl methoxydibenzoylmethane, ethylhexyl methoxycinnamate, ethyl linoleate, and cetyl ethylhexanoate. The oil-soluble substance solubilized by the solubilizing agent of the present invention may consist of only one of the oil-soluble substances exemplified above, or may consist of two or more oil-soluble substances.

[0034] The amount of the solubilizer of the present invention to be added to a pharmaceutical or cosmetic product is not particularly limited, but is generally added in an amount ranging from 1 to 30 times (by mass), or from 3 to 25 times, the amount of the oil-soluble substance.

[0035] Cosmetics containing the solubilizer of the present invention (solubilized composition using the solubilizer) include cleansing products such as shampoo, face wash, and body shampoo; creamy cosmetics such as cold cream and vanishing cream; basic cosmetics such as emulsions, beauty serums (including beauty gels), and lotions; finishing cosmetics; fragrance products such as perfumes, colognes, body mists, body sprays, and room fragrances (including room sprays); hair cosmetics such as hair styling products, hair liquids, hair rinses, and hair mists; and bath oils.

[0036] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0037] 1. Preparation of the Solubilizing Agent of the Present Invention The solubilizing agents of the present invention and comparative products shown in Tables 1 and 2 were synthesized as follows.

[0038] (Method for synthesizing the product of the present invention and the comparative product) The hydroxyl value of the polyglycerol to be used was determined, and the average degree of polymerization (n) of the polyglycerol was calculated based on (Equation 1). The fatty acids were weighed out based on (Equation 2) so as to achieve the desired esterification rate relative to the polyglycerol, and the polyglycerol and fatty acid were mixed. The average degree of polymerization calculated from the hydroxyl value of the polyglycerol used and the type of fatty acid are shown in Tables 1 and 2. 0.1% by mass (mass % relative to the mixture) of sodium hydroxide was added to this mixture, and the mixture was then heated to 220 to 250°C and stirred under a nitrogen stream while an esterification reaction was carried out until the acid value reached 1 or less, thereby preparing the product of the present invention and the comparative product.

[0039]

[0040]

[0041] 2. Evaluation of Solubilizing Ability (1) Experimental Outline Using the products of the present invention and comparative products shown in Tables 1 and 2, the solubilizing ability for oil-soluble substances was evaluated.

[0042] (2) Experimental Method The following evaluation formulations were prepared, and the solubilizing ability of each solubilizer was evaluated. The evaluation method was to check the transparency according to the following evaluation criteria immediately after preparation and after one month of storage at various temperatures: room temperature, -5°C, 5°C, and 45°C (one cycle was -5°C → 25°C → 45°C → 25°C, and the solution was left standing at each temperature for 6 hours).

[0043] (3) Evaluation Criteria for Transparency The transmittance at 680 nm was measured and evaluated according to the following evaluation criteria.

[0044] ◎: 80% or more ◯: 70% or more but less than 80% △: 50% or more but less than 70% ×: Less than 50% or separation was observed.

[0045] (4) Evaluation Formulation (% by mass) Phase A: Invention product / Comparative product X (listed in Tables 3 to 7), Oil-soluble substance Y (listed in Tables 3 to 7), Propanediol 5.0 Phase B: Preservative appropriate amount Water Remainder Total 100.0 Preparation method: After mixing the invention product / comparative product with propanediol at room temperature or 40 to 50°C, the oil-soluble substance was added to prepare Phase A, and Phase B was mixed uniformly at room temperature or 40 to 50°C, and then Phase A was added to Phase B at room temperature and stirred and mixed using a spatula until uniform.

[0046] (5) Results The evaluation results are shown in Tables 3 to 7. It was confirmed that the use of the solubilizer of the present invention makes it possible to obtain a solubilized composition that is highly transparent and has high stability over time at various temperatures: room temperature, -5°C, 5°C, 45°C, and a cycle (-5°C → 25°C → 45°C → 25°C = 1 cycle, with each temperature left standing for 6 hours). Fragrance a (floral) and fragrance b (woody) were used as the mixed fragrance as the oil-soluble substance.

[0047]

[0048]

[0049]

[0050]

[0051]

[0052] 3. Evaluation of solubilizing ability of polyhydric alcohol (1) Experimental method The following evaluation formulations were prepared, and the solubilizing ability was evaluated without and with the amount of polyhydric alcohol added. The evaluation method consisted of checking the transparency according to the following evaluation criteria immediately after preparation and after one month of storage at various temperatures: room temperature, -5°C, 5°C, and 45°C (one cycle consisting of -5°C → 25°C → 45°C → 25°C, with each temperature being left standing for 6 hours).

[0053] (2) Evaluation Criteria for Transparency The transmittance at 680 nm was measured and evaluated according to the following evaluation criteria.

[0054] ◎: 80% or more ◯: 70% or more but less than 80% △: 50% or more but less than 70% ×: Less than 50% or separation was observed (3) Evaluation formulation (mass %) Phase A: Invention product A-2 1.8 Rosemary oil 0.3 Polyhydric alcohol Z (described in Table 8) Phase B: Preservative appropriate amount Water Remainder Total 100.0 Preparation method: Invention product A-2 was mixed with the polyhydric alcohol at room temperature or 40 to 50°C, and then rosemary oil was added to prepare Phase A, and Phase B was mixed uniformly at room temperature or 40 to 50°C, and Phase A was added to Phase B at room temperature and stirred and mixed using a spatula until uniform.

[0055] (4) Results The evaluation results are shown in Table 8. It was confirmed that by using the solubilizer of the present invention, a solubilized composition having high stability over time at various temperatures can be obtained, regardless of whether polyhydric alcohol is not added or the type or amount of polyhydric alcohol is changed.

[0056]

[0057] 4. Various Synthesis Examples The products of the present invention and comparative products shown in Tables 9 and 10 were synthesized in the same manner as above.

[0058]

[0059]

[0060] (1) Experimental Method 2. Evaluation formulations similar to those in (4) were prepared, and the solubilizing ability of each solubilizer was evaluated. The evaluation method involved visually checking the transparency according to the following evaluation criteria immediately after preparation and after one month of storage at various temperatures: room temperature, -5°C, 5°C, and 45°C, cycled (-5°C → 25°C → 45°C → 25°C = one cycle, with 6 hours of standing at each temperature). (2) Transparency Evaluation Criteria ◯: Completely transparent △: Light transmission was visible to the naked eye, but the composition exhibited a bluish or milky white color ×: Cloudy or separated. (3) Results The evaluation results are shown in Tables 11 and 12. It was confirmed that the use of the solubilizer of the present invention provided a solubilized composition with high transparency and high stability over time at various temperatures: room temperature, -5°C, 5°C, and 45°C, cycled (-5°C → 25°C → 45°C → 25°C = one cycle, with 6 hours of standing at each temperature). The oil-soluble substances used in the mixed fragrance were fragrance a (floral) and fragrance b (woody).

[0061]

[0062]

[0063] Below are examples of cosmetics containing the solubilizer of the present invention. The blending amounts are in mass %. For each component (A) and component (B) in Examples 1 to 7, the type of fatty acid used and the average degree of polymerization and esterification rate of polyglycerin calculated according to (Equation 1) and (Equation 2) are shown in parentheses.

[0064] Example 1: Lotion 1 Phase A: Present invention product A-7 (average degree of polymerization of lauric acid and polyglycerol: 18.32, esterification rate: 4.9%) 1.00 (mass %) Safflower oil 0.20 Glycerin 4.00 Phase B: Hydrolyzed collagen 0.10 Dipotassium glycyrrhizinate 0.05 EDTA-2Na 0.05 Preservative ingredient appropriate amount Citric acid appropriate amount Sodium citrate appropriate amount Purified water Remainder Total 100.00 (Preparation method) Phase A was mixed uniformly at approximately 60°C and then returned to room temperature. Next, phase A was gradually added to phase B while stirring with a magnetic stirrer. Stirring was then continued for 15 minutes to complete the preparation. (Results) The transmittance at 680 nm was 98% for all samples immediately after preparation and after storage at various temperatures for one month.

[0065] Example 2: Lotion 2 Phase A: Invention Product B-6 (average degree of polymerization of myristic acid and polyglycerol: 7.51, esterification rate: 9.5%) 5.60 (mass %) Ethyl linoleate 0.40 Dipropylene glycol 3.00 Tocopherol 0.10 Phase B: Perilla extract 1.00 Preservative ingredient appropriate amount Phosphoric acid appropriate amount Sodium phosphate appropriate amount Purified water Remainder Total 100.00 (Preparation method) Phase A was mixed uniformly at approximately 80°C and then returned to room temperature. Next, phase A was gradually added to phase B while stirring with a magnetic stirrer. Stirring was then continued for 15 minutes to complete the preparation. (Results) The transmittance at 680 nm was 92% for all samples immediately after preparation and after storage at various temperatures for one month.

[0066] Example 3 Body Spray Phase A: Invention Product A-8 (average degree of polymerization of lauric acid and polyglycerol: 10.27, esterification rate: 6.1%) 0.30 (mass%) Invention Product A-9 (average degree of polymerization of myristic acid and polyglycerol: 20.65, esterification rate: 3.8%) 1.00 Lysolecithin 0.10 Menthol 0.10 Ethanol 4.00 Phase B: Hydroxyproline 0.20 Sodium pyrrolidone carboxylate 1.00 Preservative ingredient appropriate amount Citric acid appropriate amount Sodium citrate appropriate amount Purified water Remainder Total amount 100.00 (Preparation method) Phase A was mixed uniformly at approximately 60°C and then returned to room temperature. Next, phase A was gradually added to phase B while stirring with a magnetic stirrer. Stirring was then continued for 15 minutes to complete the preparation. (Results) The transmittance at 680 nm was 99% for all samples immediately after preparation and after storage at various temperatures for one month.

[0067] Example 4: Beauty Gel Phase A: Invention Product A-10 (average degree of polymerization of undecylic acid and polyglycerol: 14.27, esterification rate: 5.3%) 0.30 (mass%) Invention Product B-7 (average degree of polymerization of lauric acid and polyglycerol: 7.09, esterification rate: 9.9%) 3.00 Lemongrass oil 0.15 Glycerin 30.00 Phase B: Ascorbyl tetrahexyldecanoate 0.50 Phase C: Carbomer 0.20 Preservative ingredient appropriate amount Purified water 20.00 Phase D: Arginine 0.20 Purified water Rest Total 100.00 (Preparation method) Phase A was mixed uniformly at approximately 60°C and then returned to room temperature. Phases C and D were mixed uniformly, and then phase D was added to phase C and mixed uniformly. Next, phase B was added to phase A and mixed uniformly, and then phases A and B were gradually added to phase C and D while stirring with a paddle mixer. Stirring was continued for 15 minutes to complete the preparation. (Results) The transmittance at 680 nm was 93% for all samples immediately after preparation and after one month of storage at various temperatures.

[0068] Example 5: Cologne Phase A: Invention Product A-11 (average degree of polymerization of lauric acid and polyglycerol: 23.23, esterification rate: 3.6%) 12.00 (mass %) Fragrance c (oriental) 2.00 Dipropylene glycol 5.00 Glycerin 2.00 Phase B: Preservative ingredient appropriate amount Citric acid appropriate amount Sodium citrate appropriate amount Purified water Remainder Total 100.00 (Preparation method) Phase A was mixed uniformly at approximately 60°C, and then phase A was gradually added to phase B while stirring with a magnetic stirrer. Stirring was then continued for 15 minutes to complete the preparation. (Results) The transmittance at 680 nm was 94% for all samples immediately after preparation and after one month of storage at various temperatures.

[0069] Example 6: Room Spray Phase A: Invention Product A-12 (average degree of polymerization of myristic acid and polyglycerol: 11.89, esterification rate: 6.8%) 3.00 (mass%) Invention Product B-8 (average degree of polymerization of capric acid and polyglycerol: 7.99, esterification rate: 10.0%) 2.00 Tea tree oil 1.40 Ginger oil 1.00 Ethanol 3.00 Phase B: Preservative ingredient appropriate amount Purified water Remainder Total amount 100.00 (Preparation method) Phase A was mixed uniformly at room temperature, and then phase A was gradually added to phase B while stirring with a magnetic stirrer. Stirring was then continued for 15 minutes to complete the preparation. (Results) Immediately after preparation and after one month of storage at various temperatures, all samples had a transparent appearance.

[0070] Example 7: Hair Mist Phase A: Invention Product A-13 (average degree of polymerization of myristic acid and polyglycerol: 25.49, esterification rate: 3.0%) 18.00 (mass %) Hydrogenated farnesene 1.00 Ethylhexyl methoxycinnamate 0.80 Propylene glycol 5.00 Phase B: Preservative ingredient (as needed) Purified water Remainder Total 100.00 (Preparation method) Phase A was mixed uniformly at approximately 80°C, and then phase A was gradually added to phase B while stirring with a magnetic stirrer. Stirring was then continued for 15 minutes to complete the preparation. (Results) The transmittance at 680 nm was 95% for all samples immediately after preparation and after one month of storage at various temperatures.

[0071] The use of the solubilizer of the present invention provides a technique for easily solubilizing an oil-soluble substance in water, thereby obtaining a solubilized composition that is highly transparent and has good stability over time, thereby providing a cosmetic preparation in which an oil-soluble substance is blended in a transparent and stable manner in a highly safe polyglycerol fatty acid ester.

[0072] The present invention includes the following aspects.

[0073] 1. A solubilizer containing the following component (A) and / or component (B): Component (A): a polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 8 to 32 calculated from the hydroxyl value of the polyglycerol and an esterification rate of less than 7.3%; Component (B): a polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 4 or more but less than 8 calculated from the hydroxyl value of the polyglycerol and an esterification rate of 11% or less.

[0074] 2. The solubilizer according to 1., wherein the esterification rate of the component (A) is 7% or less.

[0075] 3. The solubilizer according to 1. or 2., wherein the esterification rate of component (A) is 1 to 7%.

[0076] 4. The solubilizer according to any one of 1. to 3., wherein the esterification rate of component (B) is 1 to 11%.

[0077] 5. A cosmetic comprising the solubilizer according to any one of 1. to 4.

[0078] 6. The cosmetic preparation according to 5., further comprising a polyhydric alcohol.

[0079] 7. A method for solubilizing an oil-soluble substance in water, using the following component (A) and / or component (B): Component (A): a polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 8 to 32 calculated from the hydroxyl value of the polyglycerol, and an esterification rate of less than 7.3%; Component (B): a polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 4 or more but less than 8 calculated from the hydroxyl value of the polyglycerol, and an esterification rate of 11% or less.

[0080] 8. The solubilization method according to 7., wherein a mixture of the solubilizing agent and a polyhydric alcohol is used in advance.

[0081] 9. The solubilization method according to 7. or 8., wherein the solubilizing agent is mixed with an oil-soluble substance to obtain a mixture, and then the mixture is added to water.

[0082] 10. The solubilization method according to any one of 7. to 9., wherein the esterification rate of the component (A) is 7% or less.

[0083] 11. The solubilization method according to any one of 7. to 10., wherein the esterification rate of the component (A) is 1 to 7%.

[0084] 12. The solubilization method according to any one of 7. to 11., wherein the esterification rate of component (B) is 1 to 11%.

[0085] This application is based on Japanese Patent Application No. 2024-30957, filed on March 1, 2024, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A solubilizer containing the following components (A) and / or (B): Component (A): A polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 8 to 32 calculated from the hydroxyl value of the polyglycerol, and an esterification rate of less than 7.3%; Component (B): A polyglycerol fatty acid ester esterified with one or more medium-chain fatty acids selected from saturated fatty acids having 10 to 14 carbon atoms, the polyglycerol fatty acid ester having an average degree of polymerization (n) of 4 or more but less than 8 calculated from the hydroxyl value of the polyglycerol, and an esterification rate of 11% or less.

2. The solubilizer according to claim 1, wherein the esterification rate of component (A) is 1 to 7%.

3. The solubilizer according to claim 1, wherein the esterification rate of component (B) is 1 to 11%.

4. The solubilizer according to claim 1, wherein the esterification rate of component (A) is 1 to 7%, and the esterification rate of component (B) is 1 to 11%.

5. A cosmetic comprising the solubilizer according to any one of claims 1 to 4.

6. The cosmetic preparation according to claim 5, further comprising a polyhydric alcohol.

7. A method for solubilizing an oil-soluble substance in water, using the solubilizing agent according to any one of claims 1 to 4.

8. The solubilization method according to claim 7, wherein a mixture of the solubilizing agent and a polyhydric alcohol is used in advance.

9. The solubilization method according to claim 7, wherein the solubilizing agent is mixed with the oil-soluble substance to obtain a mixture, and then the mixture is added to water.

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