JP7793363B2 - Cleansing agent - Google Patents

Description

The present invention relates to a cleanser. More specifically, it relates to a skin cleanser.

Cleansers used for washing the face and other skin care products typically contain higher fatty acid salts for their cleansing power and foaming properties. Furthermore, in order to improve not only cleansing power and foaming properties, but also the feel and moisturizing properties of cleansers, the addition of surfactants, moisturizers, and other additives has been investigated.

However, the higher fatty acid salts used in cleansers have the drawback of being highly irritating to the skin. To address this issue, Patent Document 1 proposes a paste-like cleanser composition containing (A) a phosphate ester surfactant, (B) a higher fatty acid salt, and (C) a solid fat with a melting point of 50°C or higher. Patent Document 2 also proposes a skin cleanser composition containing (A) a surfactant and (B) an amphiphilic ester, with the content of component (A) being 0.025 to 2% by weight.

Japanese Patent Application Publication No. 10-183194 Japanese Patent Application Laid-Open No. 2020-7303

However, when the ratio of medium-chain fatty acid salts to the total amount of higher fatty acid salts is high, skin irritation increases. The cleanser described in Patent Document 1 has a high ratio of medium-chain fatty acid salts (laurate salts) to the total amount of higher fatty acid salts, and skin irritation was not sufficiently reduced. Furthermore, the cleanser described in Patent Document 2 is liquid and is used in a form that is dispensed as a mist rather than a foam, so it does not foam. Therefore, there is still a demand for cleansers that foam well and cause little skin irritation.

As a result of extensive research into solving the above-mentioned problems, the inventors discovered that the above-mentioned problems could be solved by simultaneously blending (A) a medium-chain fatty acid having from 8 to 12 carbon atoms, (B) a long-chain fatty acid having from 14 to 22 carbon atoms, (C) a neutralizing agent, and (D) an amphoteric surfactant in a cleanser, and further adjusting the total content of components (A) and (B), the ratio of the content of component (A) to the total content of components (A) and (B), and the mass ratio of the content of component (A) to the content of component (D), thereby completing the present invention.

According to the present invention, the following inventions are provided.
[1] (A) a medium-chain fatty acid having 8 to 12 carbon atoms,
(B) a long-chain fatty acid having 14 to 22 carbon atoms;
(C) a neutralizing agent, and (D) an amphoteric surfactant;
A cleanser comprising:
the total content of the component (A) and the component (B) is 15.0% by mass or more and 45.0% by mass or less based on the total amount of the cleanser;
the content of the component (A) is 9.0% by mass or more and less than 20.0% by mass with respect to the total content of the component (A) and the component (B),
the mass ratio of the content of the component (A) to the content of the component (D) is 3.0 or less;
Cleaning agent.
[2] The cleansing agent according to [1], wherein the (A) medium-chain fatty acid having 8 to 12 carbon atoms is lauric acid.
[3] (B) A cleansing agent according to [1] or [2], wherein the long-chain fatty acid having 14 to 22 carbon atoms is at least one selected from the group consisting of myristic acid, palmitic acid, and stearic acid.
[4] The cleansing agent according to any one of [1] to [3], wherein the content of the component (A) is 9% by mass or more and less than 20% by mass with respect to the total content of the component (A) and the component (B).
[5] The cleansing agent according to any one of [1] to [4], wherein the mass ratio of the content of the component (A) to the content of the component (D) is 0.8 or more and 2.0 or less.
[6] The cleanser according to any one of [1] to [5], further comprising (E) a nonionic surfactant.
[7] (F) The cleanser according to any one of [1] to [6], further comprising a moisturizer.
[8] (G) The cleanser according to any one of [1] to [7], further comprising a solid oil component.
[9] The cleansing agent according to any one of [1] to [8], which is a skin cleanser.

The present invention provides a cleanser that foams well and is low in skin irritation.

[Cleaning agent]
The cleanser according to the present invention contains, as essential ingredients, (A) a medium-chain fatty acid having from 8 to 12 carbon atoms, (B) a long-chain fatty acid having from 14 to 22 carbon atoms, (C) a neutralizing agent, and (D) an amphoteric surfactant. Furthermore, the cleanser according to the present invention may further contain, depending on the purpose, (E) a nonionic surfactant, (F) a moisturizing agent, (G) a solid oil, and other ingredients. The cleanser according to the present invention has excellent foaming properties and low skin irritation.

((A) Medium-chain fatty acids having 8 to 12 carbon atoms)
The medium-chain fatty acid having from 8 to 12 carbon atoms may be linear, branched, saturated, or unsaturated. Specific examples of higher fatty acids having from 8 to 12 carbon atoms include caprylic acid, capric acid, and lauric acid. One or a combination of two or more of these may be blended. Among these, lauric acid is particularly preferred.

((B) Long-chain fatty acids having 14 to 22 carbon atoms)
The medium-chain fatty acid having from 14 to 22 carbon atoms may be straight-chain, branched, saturated, or unsaturated. Specific examples of higher fatty acids having from 14 to 22 carbon atoms include myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, arachidic acid, and behenic acid. One or a combination of two or more of these may be blended. It is particularly preferable to blend at least one selected from the group consisting of myristic acid, palmitic acid, and stearic acid.

The total content of components (A) and (B) is 15.0% by mass or more and 45.0% by mass or less, preferably 17.0% by mass or more and 42.0% by mass or less, and more preferably 20.0% by mass or more and 40.0% by mass or less, based on the total amount of the cleanser.
The content of component (A) is 9.0 mass% or more and less than 20.0 mass%, preferably 9.5 mass% or more and 19.0 mass% or less, and more preferably 10.0 mass% or more and 18.0 mass% or less, based on the total content of component (A) and component (B).
The mass ratio of the content of the component (A) to the content of the component (D) is 3.0 or less, preferably 0.8 or more and 2.0 or less, and more preferably 0.9 or more and 1.5 or less.
By ensuring that the content of each component satisfies the above numerical range, a cleanser with excellent foaming properties and low skin irritation can be obtained.

((C) Neutralizing Agent)
The neutralizing agent is not particularly limited, and any neutralizing agent commonly used as a material for fatty acid soaps may be used. Examples of neutralizing agents include hydroxides of alkali metal salts such as potassium hydroxide and sodium hydroxide, hydroxides of alkaline earth metals such as magnesium hydroxide and calcium hydroxide, alkanolamines such as 2-amino-2-methyl-1-propanol, monoethanolamine, diethanolamine, and triethanolamine, basic amino acids such as L-arginine, lysine, and ornithine, aqueous ammonia, ammonium hydroxide, and sodium bicarbonate. One or more of these may be used in combination. Among these, from the viewpoints of improving solubility in water and cleaning effect, one or more selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, aqueous ammonia, monoethanolamine, diethanolamine, and triethanolamine are preferred, and one or more selected from sodium hydroxide, potassium hydroxide, aqueous ammonia, monoethanolamine, diethanolamine, and triethanolamine are more preferred. In particular, it is preferable to blend one or two selected from sodium hydroxide and potassium hydroxide.

The salts of medium- and long-chain fatty acids described above are produced, for example, by neutralizing medium- and long-chain fatty acids with a neutralizing agent. However, complete neutralization is generally not achieved, and the product also contains unreacted medium- and long-chain fatty acids. In the present invention, the neutralization rate of medium- and long-chain fatty acids is not particularly limited, but is preferably 60 to 90 mol%, and more preferably 70 to 85 mol%. Therefore, the cleanser according to the present invention preferably contains 60 to 90 mol%, more preferably 70 to 85 mol%, of medium- and long-chain fatty acid salts, and preferably 10 to 40 mol%, more preferably 15 to 30 mol% of medium- and long-chain fatty acids. The content of the neutralizing agent is not particularly limited, and can be adjusted as appropriate to achieve the above neutralization rate.

((D) Amphoteric Surfactant)
The amphoteric surfactant is not particularly limited, and amphoteric surfactants commonly used as ingredients in cleansers can be used. Examples of amphoteric surfactants include betaine-based surfactants such as cocamidopropyl betaine, alkyl betaine, imidazolinium betaine, lauryl dimethylaminoacetic acid betaine, amido betaine, and sulfobetaine; and imidazoline-based amphoteric surfactants such as 2-undecyl-N,N,N-(hydroxyethylcarboxymethyl)-2-imidazoline sodium and 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt. One or a combination of two or more of these may be blended. Among these, betaine-based surfactants are particularly preferred, and it is preferable to blend at least one selected from the group consisting of cocamidopropyl betaine, alkyl betaine, and imidazolinium betaine.

In the present invention, without being bound by theory, it is presumed that by blending a medium-chain fatty acid salt and an amphoteric surfactant in a specific ratio in a cleanser, the medium-chain fatty acid salt and the amphoteric surfactant form a complex, making it difficult for the medium-chain fatty acid salt to be taken up by cells, thereby reducing skin irritation.

The content of the amphoteric surfactant is 1.0% by mass or more and 10% by mass or less, preferably 1.5% by mass or more and 8.0% by mass or less, and more preferably 2.0% by mass or more and 6.0% by mass or less, based on the total amount of the cleanser. If the content of the amphoteric surfactant falls within the above range, a cleanser with excellent foaming properties and low skin irritation can be obtained.

((E) Nonionic Surfactant)
The nonionic surfactant is not particularly limited, and nonionic surfactants commonly used as ingredients in cleansers can be used. Examples of nonionic surfactants include fatty acid ester-type nonionic surfactants such as sucrose fatty acid esters, ethylene glycol fatty acid esters, polyethylene glycol fatty acid esters, propylene glycol fatty acid esters, polypropylene glycol fatty acid esters, glycerin fatty acid esters, polyglycerin fatty acid esters, and sorbitan fatty acid esters. One or more of these may be blended in combination.

The content of nonionic surfactant is preferably 0.1% by mass or more and 10% by mass or less, and more preferably 1% by mass or more and 7% by mass or less, based on the total amount of the cleanser.

((F) Moisturizer)
The humectant is not particularly limited, and humectants commonly used as ingredients in cleansers can be used. Examples of humectants include polyethylene glycol, propylene glycol, dipropylene glycol, glycerin, diglycerin, 1,3-butylene glycol, isoprene glycol, propanediol, 1,2-hexanediol, xylitol, sorbitol, maltitol, chondroitin sulfate, hyaluronic acid, mucoitin sulfate, caronic acid, atelocollagen, sodium lactate, bile salts, dl-pyrrolidone carboxylate, short-chain soluble collagen, diglycerin (EO)PO adduct, Rosa robur extract, yarrow extract, melilot extract, etc. One or a combination of two or more of these may be blended. Among these, it is particularly preferable to blend at least one selected from the group consisting of polyethylene glycol, propylene glycol, dipropylene glycol, glycerin, diglycerin, 1,3-butylene glycol, xylitol, sorbitol, and maltitol, and it is more preferable to blend at least one selected from the group consisting of dipropylene glycol, glycerin, and sorbitol.

The content of the humectant is preferably 1% by mass or more and 45% by mass or less, more preferably 10% by mass or more and 40% by mass or less, and even more preferably 15% by mass or more and 35% by mass or less, based on the total amount of the cleanser.

((G) Solid Oil Content)
The solid oil is not particularly limited, and solid oils generally used as ingredients for cleansers can be used. The solid oil is an oil that is solid or semi-solid at room temperature (25°C). Examples of such oils include solid oils such as cocoa butter, coconut oil, horse oil, hardened coconut oil, palm oil, beef tallow, mutton oil, hardened beef tallow, palm kernel oil, lard, beef bone oil, Japan wax kernel oil, hardened oil, cow's foot fat, Japan wax, and hardened castor oil; beeswax, candelilla wax, cotton wax, carnauba wax, bayberry wax, ivotaro wax, spermaceti wax, montan wax, rice bran wax, lanolin, kapok wax, lanolin acetate, sugarcane wax, lanolin fatty acid isopropyl, hexyl laurate, reduced lanolin, and jojoba oil. Examples include waxes such as barwax, hard lanolin, shellac wax, POE lanolin alcohol ether, POE lanolin alcohol acetate, POE cholesterol ether, and POE hydrogenated lanolin alcohol ether; hydrocarbon waxes such as polyethylene wax, paraffin wax, ceresin, petrolatum, microcrystalline wax, and Lunacera; fatty acid glyceryl ethers such as monostearyl glycerin ether (batyl alcohol); and fatty acid glycerides such as acetoglyceride and tri-2-heptylundecanoic acid glyceride. One or a combination of two or more of these may be blended.

The solid oil content is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 5% by mass or less, and even more preferably 0.2% by mass or more and 2% by mass or less, based on the total amount of the cleanser.

(water)
The water to be blended into the cleanser is not particularly limited, but water used in cosmetics, quasi-drugs, etc. can be used, such as purified water, ion-exchanged water, tap water, etc.

The water content can be adjusted appropriately depending on the content of ingredients other than water. For example, the water content is preferably 20% by mass or more and 80% by mass or less, and more preferably 30% by mass or more and 70% by mass or less, based on the total amount of the cleanser.

(Other ingredients)
In addition to the above-mentioned components, the cleanser according to the present invention can contain other components used in conventionally known cleansers. Examples of other components include those listed below. The other components can be prepared by further blending one or more of the following components, as long as the effects of the present invention are achieved.

Examples of powder components include inorganic powders (e.g., talc, kaolin, mica, sericite, muscovite, phlogopite, synthetic mica, lepidolite, biotite, vermiculite, magnesium carbonate, calcium carbonate, aluminum silicate, barium silicate, calcium silicate, magnesium silicate, strontium silicate, metal tungstate, magnesium, silica, zeolite, barium sulfate, calcined calcium sulfate (calcined gypsum), calcium phosphate, fluorapatite, hydroxyapatite, ceramic powder, and metal soaps (e.g., zinc myristate). , calcium palmitate, aluminum stearate), boron nitride, etc.); organic powders (for example, polyamide resin powder (nylon powder), polyethylene powder, polymethyl methacrylate powder, polystyrene powder, styrene-acrylic acid copolymer resin powder, benzoguanamine resin powder, polytetrafluoroethylene powder, cellulose powder, etc.); inorganic white pigments (for example, titanium dioxide, zinc oxide, etc.); inorganic red pigments (for example, iron oxide (red iron oxide), iron titanate, etc.); inorganic brown pigments (for example, γ-iron oxide, etc.); inorganic yellow pigments (for example, yellow iron oxide, yellow ochre, etc.); inorganic Black pigments (e.g., black iron oxide, low-order titanium oxide, etc.); inorganic purple pigments (e.g., mango violet, cobalt violet, etc.); inorganic green pigments (e.g., chromium oxide, chromium hydroxide, cobalt titanate, etc.); inorganic blue pigments (e.g., ultramarine, Prussian blue, etc.); pearl pigments (e.g., titanium dioxide-coated mica, titanium dioxide-coated bismuth oxychloride, titanium dioxide-coated talc, colored titanium dioxide-coated mica, bismuth oxychloride, fish scale foil, etc.); metal powder pigments (e.g., aluminum powder, copper powder, etc.); zirconium, barium organic pigments such as sodium or aluminum lakes (for example, organic pigments such as Red No. 201, Red No. 202, Red No. 204, Red No. 205, Red No. 220, Red No. 226, Red No. 228, Red No. 405, Orange No. 203, Orange No. 204, Yellow No. 205, Yellow No. 401, and Blue No. 404, Red No. 3, Red No. 104, Red No. 106, Red No. 227, Red No. 230, Red No. 401, Red No. 505, Orange No. 205, Yellow No. 4, Yellow No. 5, Yellow No. 202, Yellow No. 203, Green No. 3, and Blue No. 1); natural pigments (for example, chlorophyll, beta-carotene, etc.), etc.

Liquid oils are oils that are liquid at room temperature. Examples of such oils include avocado oil, evening primrose oil, camellia oil, turtle oil, macadamia nut oil, sunflower oil, almond oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, persic oil, wheat germ oil, camellia oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, Chinese tung oil, Japanese tung oil, jojoba oil, and germ oil; cetyl octanoate, cetyl 2-ethylhexanoate, hexyldecyl dimethyloctanoate, ethyl laurate, hexyl laurate, isopropyl myristate, and 2-hexyl myristate. Cildecyl, myristyl myristate, octyldodecyl myristate, isopropyl palmitate, 2-ethylhexyl palmitate, 2-hexyldecyl palmitate, 2-heptylundecyl palmitate, butyl stearate, isocetyl stearate, isocetyl isostearate, decyl oleate, dodecyl oleate, oleyl oleate, myristyl lactate, cetyl lactate, diisostearyl malate, cholesteryl 12-hydroxystearate, castor oil fatty acid methyl ester, 2-ethylhexyl succinate, diisobutyl adipate, 2-hexyldecyl adipate, di- 2-heptylundecyl, diisopropyl sebacate, di-2-ethylhexyl sebacate, ethylene glycol di-2-ethylhexanoate, neopentyl glycol dicaprate, neopentyl glycol dioctanoate, acetoglyceride, glycerin di-2-heptylundecanoate, glycerin trioctanoate, glycerin tri-2-ethylhexanoate, glycerin trimyristate, glycerin triisopalmitate, tri-2-heptylundecanoate glyceride, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, pentaoctanoate Examples of suitable oils include ester oils such as erythritol and pentaerythritol tetra-2-ethylhexanoate; hydrocarbon oils such as liquid paraffin, squalene, pristane, and polybutene; and silicone oils such as linear polysiloxanes such as dimethylpolysiloxane, methylphenylpolysiloxane, and diphenylpolysiloxane; cyclic polysiloxanes such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexanesiloxane; and various modified polysiloxanes such as amino-modified polysiloxanes, polyether-modified polysiloxanes, alkyl-modified polysiloxanes, and fluorine-modified polysiloxanes. These oils can be used alone or in combination of two or more.

Natural water-soluble polymers include, for example, plant-derived polymers (e.g., gum arabic, tragacanth gum, galactan, guar gum, carob gum, karaya gum, carrageenan, pectin, agar, quince seed, algae colloid (cassow extract), starch (rice, corn, potato, wheat), glycyrrhizic acid); microbial-derived polymers (e.g., xanthan gum, dextran, succinoglucan, pullulan, etc.); and animal-derived polymers (e.g., collagen, casein, albumin, gelatin, etc.).

Semi-synthetic water-soluble polymers include, for example, starch-based polymers (e.g., carboxymethyl starch, methylhydroxypropyl starch, etc.); cellulose-based polymers (methyl cellulose, ethyl cellulose, methylhydroxypropyl cellulose, hydroxyethyl cellulose, sodium cellulose sulfate, hydroxypropyl cellulose, carboxymethyl cellulose, sodium carboxymethyl cellulose, crystalline cellulose, cellulose powder, etc.); and alginate-based polymers (e.g., sodium alginate, propylene glycol alginate, etc.).

Examples of UV absorbers include benzoic acid-based UV absorbers (e.g., para-aminobenzoic acid (hereinafter abbreviated as PABA), PABA monoglycerin ester, N,N-dipropoxy PABA ethyl ester, N,N-diethoxy PABA ethyl ester, N,N-dimethyl PABA ethyl ester, N,N-dimethyl PABA butyl ester, N,N-dimethyl PABA ethyl ester, etc.); anthranilic acid-based UV absorbers (e.g., homomenthyl-N-acetylanthranilate, etc.); salicylic acid-based UV absorbers (e.g., amyl salicylate, menthyl salicylate, homomenthyl salicylate, octyl salicylate, phenyl salicylate, benzyl salicylate, p-isopropyl salicylate, etc.); propanol phenyl salicylate, etc.); cinnamic acid-based ultraviolet absorbers (e.g., octyl cinnamate, ethyl 4-isopropyl cinnamate, methyl 2,5-diisopropyl cinnamate, ethyl 2,4-diisopropyl cinnamate, methyl 2,4-diisopropyl cinnamate, propyl p-methoxy cinnamate, isopropyl p-methoxy cinnamate, isoamyl p-methoxy cinnamate, octyl p-methoxy cinnamate (2-ethylhexyl p-methoxy cinnamate), 2-ethoxyethyl p-methoxy cinnamate, cyclohexyl p-methoxy cinnamate, ethyl α-cyano-β-phenyl cinnamate, 2-ethylhexyl -α-cyano-β-phenylcinnamate, glyceryl mono-2-ethylhexanoyl-diparamethoxycinnamate, etc.); benzophenone-based ultraviolet absorbers (e.g., 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4'-methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonate, 4-phenylbenzophenone, 2-ethylhexyl-4'-phenyl-benzophenone-2-carboxylate, ester, 2-hydroxy-4-n-octoxybenzophenone, 4-hydroxy-3-carboxybenzophenone, etc.); 3-(4'-methylbenzylidene)-d,l-camphor, 3-benzylidene-d,l-camphor; 2-phenyl-5-methylbenzoxazole; 2,2'-hydroxy-5-methylphenylbenzotriazole; 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole; 2-(2'-hydroxy-5'-methylphenylbenzotriazole; dibenzalazine; dianisoylmethane; 4-methoxy-4'-t-butyldibenzoylmethane; 5-(3,3-dimethyl-2-norbornylidene)-3-pentan-2-one, etc.

Examples of sequestering agents include 1-hydroxyethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid tetrasodium salt, edetate disodium, edetate trisodium, edetate tetrasodium, sodium citrate, sodium polyphosphate, sodium metaphosphate, gluconic acid, phosphoric acid, citric acid, ascorbic acid, succinic acid, edetic acid, and ethylenediaminehydroxyethyltriacetate trisodium salt.

Examples of lower alcohols include ethanol, propanol, isopropanol, isobutyl alcohol, and t-butyl alcohol.

Examples of monosaccharides include trioses (e.g., D-glyceryl aldehyde, dihydroxyacetone, etc.); tetraoses (e.g., D-erythrose, D-erythrulose, D-threose, erythritol, etc.); pentoses (e.g., L-arabinose, D-xylose, L-lyxose, D-arabinose, D-ribose, D-ribulose, D-xylulose, L-xylulose, etc.); hexoses (e.g., D-glucose, D-talose, D-busicose, D-galactose, D-fructose, L-galactose, L- -mannose, D-tagatose, etc.); heptoses (e.g., aldoheptose, heptose, etc.); octooses (e.g., octulose, etc.); deoxysugars (e.g., 2-deoxy-D-ribose, 6-deoxy-L-galactose, 6-deoxy-L-mannose, etc.); aminosugars (e.g., D-glucosamine, D-galactosamine, sialic acid, aminouronic acid, muramic acid, etc.); uronic acids (e.g., D-glucuronic acid, D-mannuronic acid, L-guluronic acid, D-galacturonic acid, L-iduronic acid, etc.), etc.

Examples of oligosaccharides include sucrose, gunthianose, umbelliferose, lactose, planteose, isolichinoses, α,α-trehalose, raffinose, lychinoses, umbilicin, stachyose, verbascoses, etc.

Amino acids include, for example, neutral amino acids (e.g., threonine, cysteine, etc.); basic amino acids (e.g., hydroxylysine, etc.); and amino acid derivatives include, for example, sodium acyl sarcosine (sodium lauroyl sarcosine), acyl glutamate, sodium acyl β-alanine, glutathione, pyrrolidone carboxylic acid, etc.

Examples of organic amines include monoethanolamine, diethanolamine, triethanolamine, morpholine, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, and 2-amino-2-methyl-1-propanol.

Examples of polymer emulsions include acrylic resin emulsion, polyethyl acrylate emulsion, acrylic resin liquid, polyacrylic alkyl ester emulsion, polyvinyl acetate resin emulsion, and natural rubber latex.

Examples of pH adjusters include sodium hydroxide, potassium hydroxide, lactic acid-sodium lactate, citric acid-sodium citrate, and succinic acid-sodium succinate.

Examples of vitamins include vitamins A, B1, B2, B6, C, E and their derivatives, pantothenic acid and its derivatives, biotin, etc.

Examples of antioxidants include tocopherols, dibutylhydroxytoluene, butylhydroxyanisole, gallic acid esters, sulfites, and bisulfites. Examples of antioxidant aids include phosphoric acid, citric acid, ascorbic acid, maleic acid, malonic acid, succinic acid, fumaric acid, cephalin, hexametaphosphate, phytic acid, and ethylenediaminetetraacetic acid.

Other ingredients that can be added include, for example, preservatives (ethylparaben, butylparaben, etc.); anti-inflammatory agents (for example, glycyrrhizinic acid derivatives, glycyrrhetinic acid derivatives, salicylic acid derivatives, hinokitiol, zinc oxide, allantoin, etc.); whitening agents (for example, placenta extract, saxifrage extract, arbutin, etc.); various extracts (for example, Phellodendron bark, Coptis chinensis, Lithospermum root, Peony, Swertia japonica, Birch, sage, Loquat, Carrot, Aloe, Mallow, Iris, Grape, Job's tears, Luffa, Lily, Saffron, Cnidium rhizome, Angelica acutiloba, Hypericum perforatum, Ononis, Garlic, Chili pepper, Citrus fruit, Angelica acutiloba, Seaweed, etc.), activators agents (e.g., royal jelly, photosensitizers, cholesterol derivatives, etc.); blood circulation promoters (e.g., nonylic acid valenylamide, nicotinic acid benzyl ester, nicotinic acid β-butoxyethyl ester, capsaicin, zingerone, cantharides tincture, ichthammol, tannic acid, α-borneol, tocopherol nicotinate, inositol hexanicotinate, cyclandelate, cinnarizine, tolazoline, acetylcholine, verapamil, cepharanthine, γ-oryzanol, etc.); antiseborrheic agents (e.g., sulfur, thianthol, etc.); anti-inflammatory agents (e.g., tranexamic acid, thiotaurine, hypotaurine, etc.); etc.

(Application)
The cleanser according to the present invention can be used for conventionally known cleansing purposes, and is particularly suitable as a skin cleanser. For example, it can be filled in a conventionally known pump-former container for cleansers. Specifically, it can be provided in the form of a face wash, body soap, hand soap, etc.

The present invention will be specifically explained based on the following examples, but the present invention is not limited to these examples. Unless otherwise specified, blend amounts are expressed in mass %.

[Examples 1 to 4, Comparative Examples 1 to 5]
<Example of cleaning agent preparation>
Cleansers of the Examples and Comparative Examples were prepared according to the formulations shown in Table 1. In Table 1, the blending ratio of each component is expressed as % by mass.

<Evaluation of cleansing products>
The cleansing agents prepared above were evaluated for skin irritation and foaming according to the following criteria. The evaluation results are shown in Table 1.

[Skin irritation]
(Evaluation method)
Each cleanser was added to human three-dimensional cultured epidermis (Labcyte Epi-model) using a test method based on the OECD test method, and the cell viability after 24 hours was determined. The cell viability of the reference cleanser (Comparative Example 1) was then set at 100, and the cell viability of each cleanser was compared to calculate a skin burden reduction score using the following formula, and skin irritation was evaluated using the following evaluation criteria. A lower skin burden reduction score indicates less skin irritation.
<Skin burden reduction score calculation formula>
Skin burden reduction score = cell viability of standard cleanser (Comparative Example 1) / cell viability of each cleanser <Evaluation criteria>
A: Skin burden reduction score of 1 or more and less than 30 B: Skin burden reduction score of 30 or more and less than 60 C: Skin burden reduction score of 60 or more and less than 90 D: Skin burden reduction score of 90 or more and less than 110 E: Skin burden reduction score of 110 or more

[Foaming]
(Evaluation method)
Three expert panelists in their 30s and 40s who had received sensory evaluation training and were able to evaluate according to a set standard were selected. The three expert panelists took 1.5g of each cleanser in their hands, lathered it, and evaluated the speed of lathering. Specifically, they rated each cleanser on a 5-point scale using the absolute evaluation below, and calculated the average score from the total evaluation points of all panelists for each cleanser to make a judgment. If the evaluation result was A to C, it was considered a pass.
<Evaluation points>
5 points: Foamed very quickly.
4 points: It foamed up quickly.
3 points: Foamed rather quickly.
2 points: Normal foaming.
1 point: It was slow to lather.
<Evaluation criteria>
A: Average score is 4.0 points or more B: Average score is 3.5 points or more and less than 4.0 points C: Average score is 3.0 points or more and less than 3.5 points D: Average score is 2.0 points or more and less than 3.0 points E: Average score is less than 2.0 points

The above results demonstrate that the cleanser of the present invention has excellent foaming properties and low skin irritation. Furthermore, when combined with the results of the comparative examples, it can be seen that the cleanser of the present invention achieves excellent effects by simultaneously blending (A) a medium-chain fatty acid having from 8 to 12 carbon atoms, (B) a long-chain fatty acid having from 14 to 22 carbon atoms, (C) a neutralizing agent, and (D) an amphoteric surfactant, and further adjusting the total content of components (A) and (B), the ratio of the content of component (A) to the total content of components (A) and (B), and the mass ratio of the content of component (A) to the content of component (D).

Claims (10)

(A) a medium-chain fatty acid having 8 to 12 carbon atoms;
(B) a long-chain fatty acid having 14 to 22 carbon atoms;
(C) a neutralizing agent, and (D) an amphoteric surfactant;
A cleanser comprising:
the total content of the component (A) and the component (B) is 15.0% by mass or more and 45.0% by mass or less based on the total amount of the cleanser;
the content of the component (A) is 9.0% by mass or more and less than 20.0% by mass with respect to the total content of the component (A) and the component (B),
the mass ratio of the content of the component (A) to the content of the component (D) is 0.9 or more and 1.5 or less;
Cleaning agent. The cleanser according to claim 1, wherein the (A) medium-chain fatty acid having 8 to 12 carbon atoms is lauric acid. The cleanser according to claim 1 or 2, wherein (B) the long-chain fatty acid having 14 to 22 carbon atoms is at least one selected from the group consisting of myristic acid, palmitic acid, and stearic acid. The cleanser according to any one of claims 1 to 3, wherein the content of component (A) is 9.5% by mass or more and 19.0% by mass or less, based on the total content of component (A) and component (B). 5. The cleansing agent according to claim 1, wherein the mass ratio of the content of the component (A) to the content of the component (D) is 1.0 or more and 1.4 or less. The cleanser according to any one of claims 1 to 5, further comprising (E) a nonionic surfactant. The cleanser according to any one of claims 1 to 6, further comprising (F) a moisturizer. The cleanser according to any one of claims 1 to 7, further comprising (G) a solid oil component. The cleanser according to any one of claims 1 to 8, which is a skin cleanser. The cleansing agent according to any one of claims 1 to 9, which is used in a form filled in a pump former container.