Washability improver for solid fatty acid

Abstract

To provide a washability improver for solid fatty acid that is less in irritating the skin and allows effective washing of solid fatty acid, and a skin washing composition containing the same.SOLUTION: To address the above problem, the inventors have studied various amino acid-based cleansing ingredients to discover that disodium cocoyl glutamate can effectively wash away solid fatty acid despite low irritation to the skin. The present invention provides a washability improver for solid fatty acid that contains disodium cocoyl glutamate as an active ingredient.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a cleaning property improver for solid fatty acids and a skin cleansing composition containing the same.

Background Art

[0002] Part of the sebum secreted from pores contains liquid fatty acids and solid fatty acids. In particular, solid fatty acids are known to cause pore clogging and horny plugs. Once solid fatty acids clog pores, they are difficult to remove and wash away.

[0003] Generally, skin cleansing agents for cleaning the skin are required to be less irritating to the skin. However, it is difficult for a mild cleansing agent with less irritation to the skin to wash away even solid fatty acids. On the other hand, if the cleaning property is enhanced to thoroughly wash away solid fatty acids, there is a problem that the irritation to the skin increases.

[0004] Amino acid-based cleaning components are known as mild cleaning components with less irritation to the skin. Amino acid-based cleaning components are often used in skin cleansing agents such as cleansing foams.

[0005] For example, Patent Document 1 aims to provide a cleansing foam cosmetic composition having no skin irritation and a mild feeling of use, and is characterized by containing an amino acid-based surfactant composed of (A) sodium lauroyl glutamate, (B) sodium cocoyl glycinate, and (C) potassium cocoyl glycinate. However, the composition described in Patent Document 1 has a problem that although it is mild in irritation to the skin, its cleaning property against solid fatty acids is low.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] As described above, conventionally, there has been a problem that in a skin cleansing composition with mild irritation to the skin, solid fatty acids cannot be thoroughly cleaned. Therefore, there is a need to develop a new skin cleansing composition that causes less irritation to the skin and can effectively clean solid fatty acids.

[0008] Therefore, an object of the present invention is to provide a cleaning property improver for solid fatty acids that enables less irritation to the skin and thorough cleaning of solid fatty acids, and a skin cleansing composition containing the same.

Means for Solving the Problems

[0009] In order to solve the above problems, the present inventors examined various amino acid-based cleaning components and found that disodium cocoyl glutamate can thoroughly clean solid fatty acids despite causing low irritation to the skin. Therefore, they found that by using disodium cocoyl glutamate, a skin cleansing composition that causes less irritation to the skin and can effectively clean solid fatty acids can be provided, and thus completed the present invention.

[0010] The present invention provides a cleaning property improver for solid fatty acids containing disodium cocoyl glutamate as an active ingredient.

[0011] The present invention also provides a cleaning property improver for solid fatty acids, which further contains water, in the above cleaning property improver for solid fatty acids.

[0012] The present invention also provides a method for improving the cleaning property of solid fatty acids, which includes adding disodium cocoyl glutamate to a skin cleansing composition.

[0013] The present invention also provides a skin cleansing composition containing a solid fatty acid detergency improver containing disodium cocoyl glutamate as an active ingredient.

[0014] The present invention also provides a skin cleansing composition further containing water in the above skin cleansing composition.

Effects of the Invention

[0015] By using the present invention, it is possible to provide a skin cleansing composition that causes less irritation to the skin and can wash solid fatty acids well.

Modes for Carrying Out the Invention

[0016] The present invention provides a solid fatty acid detergency improver containing disodium cocoyl glutamate as an active ingredient.

[0017] In the present specification, the "solid fatty acid" means a solid fatty acid, and can be a fatty acid with a high melting point, such as a saturated fatty acid. "Solid state" means being solid at least at room temperature (for example, 15 to 35°C). In the present invention, the solid fatty acid can be particularly a solid fatty acid (solid fat) contained in sebum. Examples of the solid fatty acids contained in sebum include stearic acid, palmitic acid, and lauric acid. Solid fatty acids are known to cause clogging of pores and horny plugs.

[0018] In the present specification, "detergency" means the strength of detergency, that is, the performance of removing dirt. "The detergency of the solid fatty acid is improved" in the present specification means that the performance of removing the solid fatty acid is increased, and it can also be said that the detergency rate for the solid fatty acid increases. The solid fatty acid detergency improver of the present invention can improve the detergency of the solid fatty acid when added as compared with the case where the detergency improver of the present invention is not added.

[0019] The cleaning rate is not particularly limited. For example, it can be calculated by treating the object to be cleaned with a cleaning agent and determining the ratio of the amount of the object to be cleaned removed by the treatment with the cleaning agent to the total amount of the object to be cleaned.

[0020] The cleaning rate may also be calculated based on the change in the vibration frequency of a crystal oscillator. For example, the cleaning rate can be measured using a sensor that includes a crystal oscillator and detects a change in the vibration frequency (resonance vibration frequency) of the crystal oscillator. The cleaning rate can be measured by using a QCM sensor that measures the change in the vibration frequency over time on the sensor according to the so-called Quartz crystal microbalance method (QCM method). The cleaning rate can be calculated, for example, as the ratio of the change in the vibration frequency due to the treatment with the cleaning agent to the change in the vibration frequency when the object to be cleaned attached to the sensor is completely removed.

[0021] The cleaning property improver for solid fatty acids of the present invention is not particularly limited, but the cleaning property can be improved such that the cleaning rate for solid fatty acids is preferably 30% or more, more preferably 50% or more, and even more preferably 69% or more.

[0022] Disodium cocooyl glutamate is the disodium salt of the condensate of coconut fatty acid and glutamic acid, and is an anionic surfactant (anionic surfactant) classified as an acylglutamate of amino acid-based surfactants.

[0023] Disodium cocooyl glutamate can be prepared (synthesized) by a method in which coconut fatty acid and glutamic acid are mixed at a ratio of 1:1, reacted with concentrated sulfuric acid, and then reacted with sodium hydroxide. Also, commercially available products may be used for disodium cocooyl glutamate. For example, Amisoft CS-22 manufactured by Ajinomoto Healthy Supply Co., Ltd. and Plantapon (registered trademark) Amino SCG-L manufactured by BASF Japan Ltd. can be used.

[0024] The content of disodium cocoamphodiacetate in the detergency improver is not particularly limited as long as it can improve the detergency of solid fatty acids, but preferably it is 0.01% by mass or more, more preferably 0.05% by mass or more, whereby the detergency of solid fatty acids can be improved well. Also, the content of disodium cocoamphodiacetate is not particularly limited, but for example, it can be 50% by mass or less, 30% by mass or less, or 20% by mass or less, 10% by mass or less, or 5% by mass or less, etc.

[0025] The detergency improver of the present invention contains disodium cocoamphodiacetate as an active ingredient, thereby not only improving the detergency of solid fatty acids but also suppressing the irritation to the skin. That is, the detergency improver of the present invention can reduce the irritation to the skin more compared with the conventional agents and compositions that can improve the detergency of solid fatty acids.

[0026] The detergency improver of the present invention may further contain water. The content of water in the detergency improver is not particularly limited, but for example, it may be 1% by mass or more, or 10% by mass or more. Also, the content of water in the detergency improver is not particularly limited, but for example, it can be 99.9% by mass or less, or 99.5% by mass or less, etc. By containing water, the irritation to the skin can be further reduced.

[0027] The detergency improver of the present invention is not particularly limited, but for example, it may consist of disodium cocoamphodiacetate and water. For example, the detergency improver of the present invention may be an aqueous solution of disodium cocoamphodiacetate.

[0028] The detergency improver of the present invention may further contain other components as long as the effects of the present invention are not impaired. Examples of other components include anionic surfactants other than disodium cocoamphodiacetate, cationic surfactants, amphoteric surfactants, nonionic surfactants, water-soluble polymer compounds, physiologically active components, antioxidants, sequestering agents, preservatives, ultraviolet absorbers, fragrances, humectants, salts, solvents, neutralizing agents, insect repellents, and enzymes.

[0029] The present invention also provides a method for improving the detergency of solid fatty acids, which includes adding disodium cocoamphodiacetate to a skin cleansing composition.

[0030] The skin cleansing composition is not particularly limited, and can be, for example, a skin cleansing composition such as a facial cleanser, body shampoo, cleansing agent, hand soap, shaving agent, and massage agent.

[0031] The amount of disodium cocoamphodiacetate added to the skin cleansing composition is not particularly limited as long as it can improve the detergency of the solid fatty acid. For example, by adding the content of disodium cocoamphodiacetate in the skin cleansing composition to be preferably 0.01% by mass or more, more preferably 0.05% by mass or more, the detergency of the solid fatty acid can be improved well. Also, the content of disodium cocoamphodiacetate in the skin cleansing composition is not particularly limited, and can be, for example, 50% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 5% by mass or less.

[0032] The present invention also provides a skin cleansing composition containing the above-mentioned detergency improver. Since the skin cleansing composition of the present invention contains the detergency improver for solid fatty acids of the present invention, it has the properties of causing less irritation to the skin and being able to remove solid fatty acids well.

[0033] The content of disodium cocoamphodiacetate in the skin cleansing composition is not particularly limited as long as it can improve the detergency of solid fatty acids, but preferably it is 0.01% by mass or more, more preferably 0.05% by mass or more, whereby the detergency of solid fatty acids can be improved well. Also, the content of disodium cocoamphodiacetate in the skin cleansing composition is not particularly limited, but for example, it can be 50% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 5% by mass or less, etc.

[0034] The skin cleansing composition of the present invention may further contain water. The content of water in the skin cleansing composition is not particularly limited, but for example, it may be 1% by mass or more, or may be 10% by mass or more. Also, the content of water in the skin cleansing composition is not particularly limited, but for example, it can be 99.9% by mass or less, 99.5% by mass or less, 95% by mass or less, 90% by mass or less, etc. By containing water, irritation to the skin can be further reduced.

[0035] The skin cleansing composition of the present invention may further contain other components as necessary within a range not impairing the effects of the present invention. Other components include, for example, anionic surfactants other than disodium cocoamphodiacetate, cationic surfactants, amphoteric surfactants, nonionic surfactants, water-soluble polymer compounds, physiologically active components, antioxidants, sequestering agents, preservatives, ultraviolet absorbers, fragrances, humectants, salts, solvents, neutralizing agents, insect repellents, and enzymes.

[0036] The anionic surfactant is not particularly limited, and examples thereof include potassium N-coconut fatty acid acyl glycine, sodium N-coconut fatty acid acyl taurine, sodium N-coconut fatty acid acyl glycine, ammonium N-palm kernel fatty acid acyl glycine, potassium N-coconut fatty acid acyl glutamate, triethanolamine N-coconut fatty acid acyl glutamate, sodium N-lauroyl glutamate, triethanolamine N-lauroyl glutamate, sodium N-lauroyl alanine, sodium N-stearoyl alanine, sodium lauroyl aspartate, sodium α-lauroyl sulfonate, sodium myristoyl allyl sulfonate, sodium lauryl naphthalene sulfonate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, sodium lauryl ether sulfate, sodium polyoxyethylene lauryl ether sulfate, potassium polyoxyethylene coconut fatty acid amide ether sulfate, etc. One kind or a combination of two or more kinds can be used.

[0037] The amphoteric surfactant is not particularly limited, and examples thereof include lauric acid amide propyl betaine, coconut fatty acid amide propyl betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethyl imidazolinium betaine, sodium β-aminopropionate, sodium N-lauroyl-N'-carboxymethyl-N'-hydroxyethyl ethylenediamine, lauryl dimethylaminoacetic acid betaine, coconut alkyl dimethylaminoacetic acid betaine, stearyl dimethylaminoacetic acid betaine, etc. One kind or a combination of two or more kinds can be used.

[0038] The nonionic surfactant is not particularly limited, and examples thereof include sorbitan monostearate, polyoxyethylene sorbitan laurate, polyoxyethylene sorbitan triisostearate, decyl glucoside, lauryl glucoside, polyoxyethylene hydrogenated castor oil, polyoxyethylene lauryl ether, polyoxyethylene monoisostearate, glyceryl polyoxyethylene dioleate, coconut oil fatty acid diethanolamide, coconut oil fatty acid monoethanolamide, coconut oil fatty acid N-methylethanolamide, polyoxyethylene polyoxypropylene glycol, polyethylene glycol monolaurate, and polyglyceryl monoalkyl ether. One kind or a combination of two or more kinds can be used.

[0039] The water-soluble polymer is not particularly limited, and examples thereof include hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, polyethylene glycol, highly polymerized polyethylene glycol, polyvinyl alcohol, polyglutamic acid, hydroxypropyl starch phosphate, xanthan gum, carboxyvinyl polymer, acrylic acid·alkyl methacrylate copolymer, alkyl acrylate copolymer, cationized cellulose, cationized guar gum, cationized fenugreek gum, cationized locust bean gum, cationized tara gum, cationized galactomannan, acrylic acid alkyl·methacrylic acid alkyl·polyoxyethylene copolymer, dimethyldiallylammonium chloride·acrylamide copolymer, and acrylamide·acrylic acid·dimethyldiallylammonium chloride copolymer. One kind or a combination of two or more kinds can be used.

[0040] A physiologically active ingredient refers to a substance that imparts some physiological activity to the skin when applied thereto. Examples of physiologically active ingredients include anti-inflammatory agents, anti-aging agents, ultraviolet protectants, astringents, antioxidants, humectants, blood circulation promoters, antibacterial agents, germicides, desiccants, cooling agents, warming agents, vitamins, amino acids, wound healing promoters, irritation relievers, analgesics, cell activators, and enzyme components. Physiologically active ingredients can be natural plant extract components, seaweed extract components, crude drug components, and compounds, etc. Among these, natural plant extract components, seaweed extract components, and crude drug components, etc. are particularly preferable in terms of safety.

[0041] Examples of natural plant extracts, seaweed extracts, and crude drug components include Houttuynia cordata extract, Indocalamus tessellatus extract, Althaea officinalis extract, Aloe vera extract, Prunus mume extract, Ginkgo biloba extract, Wikstroemia indica extract, Oolong tea extract, Polygonatum odoratum extract, Coptis chinensis extract, Cinnamomum cassia extract, Viola philippica extract, Armoracia rusticana extract, Citrus sinensis extract, dried seawater, seaweed extract, hydrolyzed wheat flour, hydrolyzed silk, Chamomilla recutita extract, Daucus carota extract, Artemisia princeps extract, Glycyrrhiza glabra extract, Cuscuta chinensis extract, Actinidia chinensis extract, Cucumis sativus extract, Gardenia jasminoides extract, Sasa kurilensis extract, Clara extract, Juglans regia extract, Citrus paradisi extract, Chlorella vulgaris extract, Morus alba extract, black tea extract, yeast extract, rice extract, collagen, Salvia officinalis extract, Saponaria officinalis extract, Crataegus pinnatifida extract, shea butter, Angelica gigas extract, Scoparia dulcis extract, Perilla frutescens extract, Cinnamomum camphora extract, Paeonia lactiflora extract, Betula platyphylla extract, Stellaria media extract, Glycine max extract, Equisetum arvense extract, Thymus vulgaris extract, tea extract, Cinnamomum camphora extract, Coptis chinensis extract, Angelica dahurica extract, Aralia cordata extract, Saururus chinensis extract, Solanum lycopersicum extract, natto extract, Daucus carota extract, Allium sativum extract, Rosa multiflora extract, honey, Hamamelis virginiana extract, Coix lacryma-jobi extract, bisabolol, Pyrus pyrifolia extract, Buchloe dactyloides extract, Vitis vinifera extract, propolis, Luffa cylindrica extract, Mentha piperita extract, Ficus carica extract, Humulus lupulus extract, jojoba oil, Madonna lily flower extract, Celtis sinensis extract, Momordica grosvenori extract, Melissa officinalis extract, Prunus persica extract, Saxifraga stolonifera extract, Citrus junos extract, Artemisia princeps extract, Lavandula angustifolia extract, Citrus limon extract, Lactuca indica extract, Rosmarinus officinalis extract, and royal jelly, etc.

[0042] As physiological active ingredients other than natural plant extracts, seaweed extracts and crude drug ingredients, for example, biopolymers such as deoxyribonucleic acid, collagen, elastin, chitin, chitosan, hydrolyzed eggshell membrane, amino acids, sodium lactate, urea, sodium pyrrolidone carboxylate, betaine, whey and other moisturizing ingredients, oily ingredients such as sphingolipids, ceramides, cholesterol, cholesterol derivatives, phospholipids, anti-inflammatory agents such as ε-aminocaproic acid, glycyrrhizic acid, β-glycyrrhetinic acid, lysozyme chloride, guaiazulene, hydrocortisone, vitamins (A, B2, B6, C, D, E), calcium pantothenate, biotin, nicotinamide, vitamin C esters and other vitamins, active ingredients such as allantoin, diisopropylamine dichloroacetate, 4-aminomethylcyclohexanecarboxylic acid, antioxidants such as tocopherol, carotenoid, flavonoid, tannin, lignan, saponin, cell activators such as α-hydroxy acid, β-hydroxy acid, blood circulation promoters such as γ-oryzanol, vitamin E derivatives, bactericides such as isopropylmethylphenol, triclosan, hinokitiol, benzalkonium chloride, cooling agents such as l-menthol, peppermint oil, wound healing agents such as retinol and retinol derivatives, etc. can be mentioned.

[0043] Although not particularly limited, the skin cleansing composition of the present invention can preferably have a cleaning rate of 30% or more, more preferably 50% or more, and still more preferably 69% or more with respect to solid fatty acids.

Examples

[0044] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.

[0045] (Evaluation method for detergency of solid fatty acids) The evaluation method for detergency of solid fatty acids by sensory evaluation will be described below.

[0046] On a hydrophobic plate (Helio Plate SB6), 30 mg of stearic acid (manufactured by Nagara Science Co., Ltd.) mixed with Nile Red was applied as a stain of solid fatty acid. Then, it was immersed in the tested cleaning solution for 20 seconds for cleaning. After that, for each cleaning solution, 10 professional panels evaluated the degree of color fading before and after cleaning. Specifically, they evaluated whether it was "well removed" or "not so". And the evaluation of the removal of the solid fatty acid stain was carried out using the following evaluation criteria.

[0047] [Removal of solid fatty acid stain] ◎: Extremely good (the number of people who answered "well removed" is 8 or more) ○: Good (the number of people who answered "well removed" is 6 or more and less than 8) △: Slightly bad (the number of people who answered "well removed" is 4 or more and less than 6) ×: Bad (the number of people who answered "well removed" is less than 4)

[0048] (Method for evaluating irritation) The irritation of the cleaning solution was evaluated using the following method.

[0049] 10 professional panels used the cleaning solution to wash the skin and evaluated the tingling feeling of the skin before and after washing using the following evaluation criteria.

[0050] [Irritation to the skin] ◎: Extremely good (the number of people who answered "tingling" is 0) ○: Good (the number of people who answered "tingling" is 1 or more and less than 3) △: Slightly bad (the number of people who answered "tingling" is 3 or more and less than 5) ×: Bad (the number of people who answered "tingling" is 5 or more)

[0051] [Examples 1 to 6] As examples of the cleaning performance improver for solid fatty acids and the skin cleaning agent composition of the present invention, the cleaning liquids of Examples 1 to 6 were prepared. The cleaning liquids of Examples 1 to 6 were aqueous solutions of 0.05, 0.1, 0.5, 1, 5, or 10% by mass of disodium cocooyl glutamate (manufactured by Ajinomoto Health Supply Co., Ltd.). The cleaning performance and irritation of these cleaning liquids on solid fatty acids were evaluated.

[0052] As a result, as shown in Table 1, the cleaning performance of the cleaning liquids of Examples 1 to 6 on solid fatty acids was all evaluated as "extremely good" or "good". In addition, as a result of evaluating the irritation of the cleaning liquids of Examples 1 to 6 on the skin, all were evaluated as having low irritation.

[0053] 〔Comparative Examples 1 to 4〕 As the cleaning liquids of the comparative examples, aqueous solutions of 1% by mass of TEA lauroyl glutamate (manufactured by Ajinomoto Health Supply Co., Ltd.) (Comparative Example 1), TEA lauroyl sarcosinate (manufactured by Kawaken Fine Chemicals Co., Ltd.) (Comparative Example 2), SDS (manufactured by Tokyo Chemical Industry Co., Ltd.) (Comparative Example 3), and potassium laurate (manufactured by Wako Pure Chemical Industries, Ltd.) (Comparative Example 4) were prepared, and the cleaning performance and irritation of solid fatty acids were evaluated.

[0054] As a result, as shown in Table 1, the cleaning liquids of Comparative Examples 1 and 2 had low cleaning performance of solid fatty acids by sensory evaluation. In addition, the cleaning liquids of Comparative Examples 3 and 4 were evaluated as having good cleaning performance of solid fatty acids but high irritation.

[0055]

Table 1

[0056] 〔Example 7〕 As an example of the skin cleansing composition of the present invention, a cleansing liquid having the composition shown in Table 2 was prepared. The cleansing liquid of Example 7 contained 3% by mass of disodium cocoamido glutamate. In addition, glycerin (manufactured by Kao Corporation), PEG-6 (manufactured by NOF Corporation), sodium cocoamido methyl taurate (manufactured by NOF Corporation), polyquaternium-7 (manufactured by BASF Japan Ltd.) and EDTA-4Na (manufactured by BASF Japan Ltd.) were used.

[0057] As shown in Table 2, the cleansing liquid of Example 7 had extremely good detergency for solid fatty acids by sensory evaluation. Also, the cleansing liquid of Example 7 was evaluated to have extremely low irritation.

[0058] Therefore, it was shown that a skin cleansing composition capable of washing solid fatty acids well with little irritation to the skin can be provided by containing a detergent improver for solid fatty acids containing disodium cocoamido glutamate as an active ingredient.

[0059]

Table 2

Industrial Applicability

[0060] The present invention can be suitably used for the production of skin cleansing compositions.

Claims

1. A cleaning property improver for solid fatty acids, containing sodium cocoamphoacetate as an active ingredient.

2. The cleaning property improver for solid fatty acids according to Claim 1, further containing water.

3. A method for improving the cleaning property of solid fatty acids, including adding sodium cocoamphoacetate to a skin cleaning agent composition.

4. A skin cleaning agent composition containing a cleaning property improver for solid fatty acids, containing sodium cocoamphoacetate as an active ingredient.

5. The skin cleaning agent composition according to Claim 4, further containing water.

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