Bath solid composition

Abstract

To provide a solid composition for bathing comprising an oil solution which can be solidified, is quickly dissolved in bath water, causes less foaming and oil floating of bath water and gives a good moisture-retaining feeling after bathing.SOLUTION: There is provided a solid composition for bathing which comprises the following components (A) and (B): (A) an oil solution and (B) a nonionic surfactant containing 50 mass% or more of a polyoxyethylene alkyl ether (b1), wherein the component (b1) has an average addition molar number of ethylene oxide of 15 or more, the content of the component (B) in the solid composition for bathing is less than 20 mass%, the mass ratio (A) / (B) of the component (A) to the component (B) is 0.20 or more and 7.0 or less and the total content of the component (A) and the component (B) in the solid composition for bathing is 15 mass% or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a solid composition for use in baths. [Background technology]

[0002] It is known that including oils in bath salts can further enhance their moisturizing and warming effects. Bath additives or bath cosmetics that contain oils and are solid are also being investigated. For example, Patent Document 1 discloses a bath additive composition containing a powder composition comprising an oily component containing at least one type of carotenoid, a surfactant containing at least one type of phospholipid, and an excipient, wherein the amount of the surfactant is within a predetermined range relative to the oily component, which is easily dispersed uniformly in bath water, does not impair the appearance of the bath water, and has excellent skin care effects and stability. Patent Document 2 discloses that a fragrance granule containing a predetermined amount of liquid nonionic surfactant, fragrance, and polyoxyalkylene, wherein the average number of added moles of HLB and ethyleneoxy groups is above a predetermined value, can suppress the occurrence of stickiness and sufficiently increase particle strength, thereby improving storage stability and moldability when applied as a component in bath additives and the like.

[0003] Solid bath additives that contain organic acids and carbonates and produce carbonate-like bubbles are also known. For example, Patent Document 3 discloses a bath additive composition containing organic acids, carbonates, a nonionic surfactant, polyethylene glycol having a number-average molecular weight within a predetermined range, and a thickener, which generates fine bubbles on the surface of the bathwater, can retain those bubbles well, and can also achieve high storage stability. Furthermore, Patent Document 4 discloses a solid bath additive containing an organic acid, a carbonate, and an oily component, comprising granules containing one or more oils selected from fatty acid esters and fatty acid glycers, an oily component containing a predetermined nonionic surfactant, and a water-soluble polymer in a specific proportion, as well as a foaming bath additive composition containing a carbonate and an organic acid, and states that the granules have good granulation properties while increasing the proportion of oily components in order to sufficiently enhance the warming effect of carbon dioxide. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2009-132628 [Patent Document 2] Japanese Patent Publication No. 2014-94915 [Patent Document 3] Japanese Patent Publication No. 2015-113320 [Patent Document 4] Japanese Patent Publication No. 2019-142792 [Overview of the project] [Problems that the invention aims to solve]

[0005] As described in the aforementioned patent document, in solid bath additives or bath cosmetics containing oils, the oil is supported on a solid. These solid bath additives or bath cosmetics can contain a large amount of oil to provide moisturizing effects, etc., and even in that case, they must be able to be solidified. Furthermore, the solid on which the oil is supported must dissolve quickly in the bath water, allowing the oil to disperse in the bath water. In addition, if the foam does not dissipate well from the surface of the bath water when added to the bath, or if oil floats, the appearance of the bath water will be poor, and it may induce the washing away of foam and oil after bathing, which may reduce the moisturizing effect of the oil. Therefore, it is desirable to suppress foaming and oil floating in the bath water.

[0006] The present invention relates to a solid bath composition containing an oil agent, which can be solidified, quickly dissolves in bath water, has less foaming and oil floating in bath water, and provides a good moisturizing feeling after bathing.

Means for Solving the Problems

[0007] The present inventor has found that the above problems can be solved by using a solid bath composition containing an oil agent and a specific nonionic surfactant in a specific ratio. That is, the present invention relates to the following. [1] The following components (A) and (B): (A) Oil agent (B) A nonionic surfactant containing 50% by mass or more of polyoxyethylene alkyl ether (b1) A solid bath composition containing the above components, wherein the average number of moles of ethylene oxide added to the component (b1) is 15 or more, the content of the component (B) in the solid bath composition is less than 20% by mass, and the mass ratio (A) / (B) of the component (A) to the component (B) is 0.20 or more and 7.0 or less, and the total content of the component (A) and the component (B) in the solid bath composition is 15% by mass or more. [2] A bath agent containing the solid bath composition according to [1] above.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a solid bath composition that can be solidified while containing an oil agent, quickly dissolves in bath water, has less foaming and oil floating in bath water, and provides a good moisturizing feeling after bathing.

Modes for Carrying Out the Invention

[0009] [Solid Bath Composition] The solid bath composition of the present invention contains the following components (A) and (B): (A) Oil agent [[ID=3G]] (B) A nonionic surfactant containing polyoxyethylene alkyl ether (b1) of 50% by mass or more A solid bath composition containing the above, wherein the average number of moles of ethylene oxide added to component (b1) is 15 or more, the content of component (B) in the solid bath composition is less than 20% by mass, the mass ratio of component (A) to component (B) (A) / (B) is 0.20 or more and 7.0 or less, and the total content of component (A) and component (B) in the solid bath composition is 15% by mass or more.

[0010] In this invention, "solid" means solid at 25°C. Furthermore, the "bath solid composition" of this invention means a solid composition that constitutes at least a part of a bath additive, and includes both solid compositions that can be used as a bath additive as is, and solid compositions that are included in a bath additive as a component of the bath additive. In other words, the bath solid composition of this invention is also an intermediate product for bath additives.

[0011] The solid bath composition of the present invention, by having the above configuration, can be solidified while containing an oil agent, dissolves quickly in bath water, reduces foaming and oiliness in the bath water, and provides a good moisturizing feeling (skin feel after bathing (moist feeling)) after bathing.

[0012] <Ingredient (A): Oil> The solid bath composition of the present invention (hereinafter also simply referred to as "the composition") contains an oil as component (A). Component (A) is preferably a liquid oil from the viewpoint of supporting it on component (b1), etc., and from the viewpoint of improving the moisturizing sensation during bathing. In the present invention, "liquid oil" refers to an oil that is fluid under 1 atmosphere and 25°C, and "solid oil" refers to an oil that is not fluid under the same conditions.

[0013] Component (A) is typically an oil used in bath additives, and may include, for example, one or more selected from the group consisting of silicone oil, ester oil, ether oil, hydrocarbon oil, higher alcohol, and higher fatty acid.

[0014] (Silicone oil) As the silicone oil, one or more selected from the group consisting of dimethylpolysiloxane (dimethicone), dimethiconol (dimethylpolysiloxane having a hydroxyl group at the end), methylphenylpolysiloxane, and modified silicones are preferred. Examples of modified silicones include amino-modified silicones (dimethylpolysiloxanes having amino groups, such as amodimethicone), polyether-modified silicones, aminopolyether-modified silicones (silicones having amino groups and polyether structures), glyceryl-modified silicones, carboxy-modified silicones, fatty acid-modified silicones, alcohol-modified silicones, aliphatic alcohol-modified silicones, epoxy-modified silicones, fluorine-modified silicones, alkyl-modified silicones, and the like. Among the above, from the viewpoint of facilitating the solidification of the composition, from the viewpoint of dispersibility in bath water, and from the viewpoint of improving moisturizing sensation during bathing, the silicone oil is preferably one or more selected from the group consisting of dimethylpolysiloxane, dimethiconol, methylphenylpolysiloxane, and modified silicone, more preferably one or more selected from the group consisting of dimethylpolysiloxane, dimethiconol, amino-modified silicone, polyether-modified silicone, and aminopolyether-modified silicone, and even more preferably dimethylpolysiloxane.

[0015] (Ester oil) The ester oil is preferably in liquid form under 1 atmosphere and 25°C. Examples of ester oils include esters of monocarboxylic acid and monohydric alcohol, esters of monocarboxylic acid and polyhydric alcohol, and esters of polycarboxylic acid and monohydric alcohol.

[0016] Examples of esters of monovalent carboxylic acids and monovalent alcohols include esters represented by the following general formula (1). R 1 -COO-R 2 (1) In general formula (1), R 1R may be substituted with a hydroxyl group and represents a linear or branched alkyl or alkenyl group having 1 to 25 carbon atoms, or an aromatic hydrocarbon group having 6 to 24 carbon atoms. 2 This represents a linear or branched alkyl or alkenyl group having 1 to 30 carbon atoms.

[0017] R 1 When is an alkyl group or an alkenyl group, the number of carbon atoms is preferably 7 or more, preferably 23 or less, more preferably 21 or less, even more preferably 19 or less, and even more preferably 17 or less. R 1 If the group is an aromatic hydrocarbon group, the number of carbon atoms is preferably 6 or more, preferably 22 or less, and more preferably 20 or less. The number of carbon atoms in R2 is preferably 2 or more, preferably 28 or less, more preferably 24 or less, and even more preferably 20 or less.

[0018] Specific examples of esters represented by general formula (1) include cetyl isooctanoate, stearyl isooctanoate, isononyl isononanoate, isotridecyl isononanoate, hexyl laurate, isostearyl laurate, butyl myristate, isopropyl myristate, decyl myristate, isotridecyl myristate, isocetyl myristate, isostearyl myristate, octyldodecyl myristate, isopropyl palmitate, 2-ethylhexyl palmitate, palmitate Examples include isostearyl benzoate, 2-hexyldecyl palmitate, 2-ethylhexyl stearate, 2-hexyldecyl stearate, isopropyl isostearate, 2-hexyldecyl isostearate, ethyl oleate, isodecyl oleate, oleyl oleate, octyldodecyl oleate, ethyl linoleate, isopropyl linoleate, lanolin acetate, methyl castor oil fatty acid (methyl ricinoleate), and alkyl benzoate (alkyl with 12-15 carbon atoms). These are liquid under 1 atmosphere and 25°C.

[0019] Examples of esters of monocarboxylic acids and monohydric alcohols also include esters represented by the following general formula (2). R 3 -COO-(AO) n -R 4 (2) In general formula (2), R 3 represents an alkyl group or an alkenyl group which may be substituted by a hydroxyl group and has 1 to 25 carbon atoms in a straight chain or a branched chain, and R 4 represents an aromatic-containing hydrocarbon group having 6 to 24 carbon atoms. AO represents an alkyleneoxy group having 2 to 4 carbon atoms, and n represents an average addition mole number of 1 to 50. R 3 is preferably an alkyl group having 7 or more carbon atoms, and preferably 23 or less, more preferably 21 or less, still more preferably 19 or less carbon atoms. R 4 is preferably an aromatic-containing hydrocarbon group having 6 or more carbon atoms, and preferably 22 or less, more preferably 20 or less, still more preferably 18 or less carbon atoms, and even more preferably a benzyl group. The AO group is preferably a propyleneoxy group, and n is preferably 1 to 10, more preferably 1 to 5. Specific examples of the ester represented by the general formula (2) include esters of myristic acid and 3 moles of propylene oxide adduct of benzyl alcohol, esters of 2-ethylhexanoic acid and 3 moles of propylene oxide adduct of benzyl alcohol, and the like.

[0020] Examples of esters of monocarboxylic acids and polyhydric alcohols include esters represented by the following general formula (3). R 5 -(OCOR 6 ) p (3) In general formula (3), R 5 represents a polyhydric alcohol residue, preferably a hydrocarbon group having 2 to 10 carbon atoms, and R 6 represents a monocarboxylic acid residue having 1 to 25 carbon atoms, and p represents an integer of 2 to 10. Note that R5 The group may have an ether bond, but is preferably a linear or branched hydrocarbon group having 2 to 10 carbon atoms. Also, the number of p is the same as the number of hydroxyl groups in the polyhydric alcohol. R 6 The alkyl group preferably has 7 or more carbon atoms, and more preferably has 23 or fewer carbon atoms, more preferably 21 or fewer, and even more preferably 19 or fewer carbon atoms.

[0021] Examples of esters represented by general formula (3) include propylene glycol dicaprate, propylene glycol dioleate, neopentyl glycol dicaprate, neopentyl glycol di2-ethylhexanoate, di(caprylic / capric acid)propanediol, propanediol diisostearate, ethylene glycol di2-ethylhexanoate, caprylic / capric acid triglyceride, glyceryl tri2-ethylhexylate, glyceryl tri2-heptylundecanoate, trimethylolpropane tri2-ethylhexylate, trimethylolpropane triisostearate, and pentaerythritol tetra-2-ethylhexanoate. These are liquids under 1 atmosphere and 25°C. Ester oils can be either synthetic ester oils or natural oils and fats. Examples of natural oils and fats include triglycerides such as avocado oil, olive oil, sesame oil, rice bran oil, safflower oil, soybean oil, corn oil, rapeseed oil, castor oil, cottonseed oil, and mink oil. These are liquid under 1 atmosphere and 25°C.

[0022] Esters of polycarboxylic acids and monohydric alcohols include those represented by the following general formula (4). R 7 -(COOR 8 ) q (4) In general formula (4), R 7 R is a polyvalent carboxylic acid residue having 2 to 10 carbon atoms. 8 represents a monohydric alcohol residue with 1 to 25 carbon atoms, and q is an integer between 2 and 10. Furthermore, q is the same number as the carboxyl groups present in the polyhydric carboxylic acid. R 8 It is preferably 3 or more, and preferably 23 or less, more preferably 21 or less, and even more preferably 19 or less. Specifically, examples include diisostearyl malate, di-2-ethylhexyl succinate, diisobutyl adipate, di-2-heptyl undecyl adipate, di-2-ethylhexyl sebacate, diisopropyl sebacate, and tri-2-ethylhexyl trimellitate. These are liquid under 1 atmosphere and 25°C.

[0023] Among the above, from the viewpoint of facilitating the solidification of the composition, from the viewpoint of dispersibility in bath water, and from the viewpoint of improving moisturizing sensation during bathing, the ester oil is preferably one or more selected from the group consisting of esters represented by general formula (1), general formula (3), and general formula (4), more preferably one or more selected from the group consisting of esters represented by general formula (1) and general formula (3), and even more preferably one or more selected from the group consisting of octyldodecyl myristate, isopropyl palmitate, and tri(caprylic / capric acid)glyceride.

[0024] (Ether oil) The ether oil is preferably in liquid form under 1 atmosphere and 25°C. Examples of ether oils include dialkyl ether compounds represented by the following general formula (5). R 9 -OR 10 (5) In general formula (5), R 9 and R 10 Each of these independently represents a linear or branched alkyl or alkenyl group having 6 to 22 carbon atoms, or an aromatic hydrocarbon group having 6 to 24 carbon atoms. R 9 and R 10 From the viewpoint of facilitating the solidification of the composition, dispersibility in bath water, and improving the moisturizing sensation during bathing, the alkyl group is preferably an alkyl group, and its carbon number is preferably 8 or more, preferably 18 or less, more preferably 16 or less, and even more preferably 12 or less.

[0025] (Hydrogen oil) The hydrocarbon oil is preferably in liquid form at 1 atmosphere and 25°C. Examples of hydrocarbon oils include one or more selected from the group consisting of squalene, squalane, liquid paraffin, liquid isoparaffin, isohexadecane, isoeicosane, hydrogenated polyisobutene, light liquid isoparaffin, heavy liquid isoparaffin, α-olefin oligomer, and cycloparaffin. These are liquid at 1 atmosphere and 25°C.

[0026] (High-grade alcohol) The higher alcohol is preferably in liquid form at 1 atmosphere and 25°C. The higher alcohol is preferably an aliphatic monohydric alcohol having 12 or more carbon atoms, more preferably 12 to 22 carbon atoms. Examples include one or more selected from the group consisting of lauryl alcohol, cetyl alcohol, myristyl alcohol, oleyl alcohol, stearyl alcohol, isostearyl alcohol, 2-octyldodecanol, behenyl alcohol, and cetostearyl alcohol. Note that lauryl alcohol, oleyl alcohol, isostearyl alcohol, and 2-octyldodecanol are liquid at 1 atmosphere and 25°C, while cetyl alcohol, myristyl alcohol, stearyl alcohol, behenyl alcohol, and cetostearyl alcohol are solid.

[0027] (higher fatty acids) The higher fatty acids are preferably in liquid form at 1 atmosphere and 25°C. Preferred higher fatty acids are those with 8 or more carbon atoms, preferably 12 or more carbon atoms. Examples include one or more selected from the group consisting of capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, coconut oil fatty acid, lanolin fatty acid, isostearyl acid, and isopalmitic acid. Oleic acid, isostearyl acid, and isopalmitic acid are liquid at 1 atmosphere and 25°C, while capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, and coconut oil fatty acid are solid at 1 atmosphere and 25°C. Lanolin fatty acid is preferably in liquid form.

[0028] Component (A) can be used in combination of one or more of the above. Among the above, component (A) is preferably one or more selected from the group consisting of silicone oil, ester oil, and hydrocarbon oil, from the viewpoint of facilitating the solidification of the composition, dispersibility in bath water, and improvement of moisturizing feeling after bathing; more preferably one or more selected from the group consisting of esters represented by the general formula (1), esters represented by the general formula (3), dimethylpolysiloxane, and liquid paraffin; even more preferably one or more selected from the group consisting of tri(caprylic / capric acid) glyceryl, octyldodecyl myristate, isopropyl palmitate, dimethylpolysiloxane, and liquid paraffin; and even more preferably one or more selected from the group consisting of tri(caprylic / capric acid) glyceryl, octyldodecyl myristate, and isopropyl palmitate.

[0029] <Ingredient (B): Nonionic surfactant> The bath solid composition of the present invention contains a nonionic surfactant as component (B), comprising 50% by mass or more of polyoxyethylene alkyl ether (b1). Furthermore, the average number of ethylene oxide added to the polyoxyethylene alkyl ether (b1) is 15 or more. The solid bath composition of the present invention, by containing component (B) in a predetermined proportion, can be solidified while containing an oil agent, dissolves quickly in bath water, reduces foaming and oiliness in the bath water, and provides excellent moisturizing after bathing.

[0030] (Component (b1): Polyoxyethylene alkyl ether) The nonionic surfactant component (B) contains 50% by mass or more of polyoxyethylene alkyl ether (b1), and the average number of moles of ethylene oxide added to component (b1) is 15 or more. In the present invention, the average number of moles of ethylene oxide added to component (b1) (hereinafter also referred to as "average number of moles of EO added") means the weighted average value of the average number of moles of EO added to two or more polyoxyethylene alkyl ethers when two or more polyoxyethylene alkyl ethers are used as component (b1). The average number of moles of ethylene oxide added to component (b1) is 15 or more, preferably 18 or more, more preferably 20 or more, even more preferably 22 or more, and also preferably 150 or less, more preferably 120 or less, even more preferably 100 or less, even more preferably 80 or less, even more preferably 60 or less, and even more preferably 40 or less, from the viewpoint of facilitating the solidification of the composition and improving the dissolution rate in the bath water. Among nonionic surfactants, using polyoxyethylene alkyl ether (b1) is thought to result in a solid bath composition in which component (b1) forms plate-like molecular crystals at room temperature (25°C), allowing it to support a large amount of oil in its voids. Furthermore, since component (b1) has an average number of ethylene oxide addition moles of 15 or more, the dissolution rate in bath water is further improved.

[0031] The average number of moles of ethylene oxide added to polyoxyethylene alkyl ether can be determined using high-performance liquid chromatography (HPLC) by the method described in Japanese Patent Publication No. 2019-182828.

[0032] Component (b1) is preferably solid at 25°C, from the viewpoint of supporting a large amount of the oil component (A) and facilitating the solidification of the composition. Specifically, the melting or freezing point of component (b1) is preferably 25°C or higher, more preferably 30°C or higher, and even more preferably 32°C or higher. There is no upper limit to the melting or freezing point of component (b1), but it is usually 100°C or lower, and preferably 80°C or lower.

[0033] The number of alkyl carbon atoms in the polyoxyethylene alkyl ether used as component (b1) is preferably 8 or more, more preferably 10 or more, even more preferably 12 or more, even more preferably 14 or more, and even more preferably 16 or more, from the viewpoint of facilitating the solidification of the composition, and preferably 36 or less, more preferably 32 or less, even more preferably 28 or less, even more preferably 24 or less, and even more preferably 22 or less, from the viewpoint of improving the dissolution rate in the bath water.

[0034] Specific examples of component (b1) include polyoxyethylene octyl ether, polyoxyethylene ethylhexyl ether, polyoxyethylene nonyl ether, polyoxyethylene decyl ether, polyoxyethylene undecyl ether, polyoxyethylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyethylene myristyl ether, polyoxyethylene pentadecyl ether, polyoxyethylene cetyl ether, polyoxyethylene heptadecyl ether, polyoxyethylene stearyl ether, polyoxyethylene behenyl ether, etc., and one or more of these can be used in combination. Among the above, from the viewpoint of facilitating the solidification of the composition and improving the dissolution rate in the bath water, component (b1) is preferably one or more selected from the group consisting of polyoxyethylene decyl ether, polyoxyethylene undecyl ether, polyoxyethylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyethylene myristyl ether, polyoxyethylene pentadecyl ether, polyoxyethylene cetyl ether, polyoxyethylene heptadecyl ether, polyoxyethylene stearyl ether, and polyoxyethylene behenyl ether; more preferably one or more selected from the group consisting of polyoxyethylene lauryl ether, polyoxyethylene myristyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, and polyoxyethylene behenyl ether; and even more preferably one or more selected from the group consisting of polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, and polyoxyethylene behenyl ether.

[0035] The content of component (b1) in component (B) is 50% by mass or more, preferably 55% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 75% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and also 100% by mass or less, from the viewpoint of facilitating the solidification of the composition and improving the dissolution rate in the bath water.

[0036] (Component (b2): Nonionic surfactant other than component (b1)) The bath solid composition of the present invention may further contain a nonionic surfactant other than component (b1) as component (b2). Examples of nonionic surfactants other than component (b1) include polyoxyethylene alkenyl ethers, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene fatty acid esters, alkyl glucosides, alkyl alkanolamides, alkyl glyceryl ethers, higher fatty acid sucrose esters, polyglycerin fatty acid esters, polyoxyethylene hydrogenated castor oil, and alkyl saccharides. The content of component (b2) in component (B) is 50% by mass or less, preferably 45% by mass or less, more preferably 40% by mass or less, even more preferably 35% by mass or less, even more preferably 30% by mass or less, even more preferably 20% by mass or less, and even more preferably 15% by mass or less, from the viewpoint of facilitating the solidification of the composition and improving the dissolution rate in the bath water.

[0037] <Content> The content of component (A) in the solid bath composition is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, even more preferably 5% by mass or more, even more preferably 7% by mass or more, and even more preferably 9% by mass or more, from the viewpoint of facilitating the solidification of the composition and suppressing foaming and oil separation in the bath water, and is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less.

[0038] From the viewpoint of improving the dissolution rate in bath water, the content of component (B) in the solid bath composition is less than 20% by mass. From the viewpoint of suppressing oil floating in the bath water, the content of component (B) in the solid bath composition is preferably 1.9% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, and even more preferably 5% by mass or more. From the viewpoint of improving the dissolution rate in bath water and suppressing foaming of the bath water, it is preferably 19% by mass or less.

[0039] The content of component (b1) in the solid bath composition is preferably 0.95% by mass or more, more preferably 1% by mass or more, even more preferably 1.5% by mass or more, even more preferably 2.5% by mass or more, and even more preferably 5% by mass or more, and also less than 20% by mass, preferably 19% by mass or less, from the viewpoint of facilitating the solidification of the composition and improving the dissolution rate in bath water.

[0040] In the bath solid composition of the present invention, the mass ratio (A) / (B) of component (A) to component (B) is 0.20 or higher, preferably 0.30 or higher, more preferably 0.40 or higher, and even more preferably 0.50 or higher, from the viewpoint of improving the dissolution rate in bath water and suppressing foaming of the bath water. Furthermore, from the viewpoint of enabling the solidification of the composition and suppressing oil floating in the bath water, it is 7.0 or lower, preferably 6.0 or lower, more preferably 5.7 or lower, even more preferably 5.0 or lower, even more preferably 4.5 or lower, and even more preferably 4.0 or lower.

[0041] The total content of component (A) and component (B) in the bath solid composition is 15% by mass or more, preferably 20% by mass or more, and more preferably 25% by mass or more, from the viewpoint of obtaining a moisturizing feeling after bathing. There is no particular upper limit, but from the viewpoint of facilitating the solidification of the composition and the freedom of formulation, it is preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, even more preferably 50% by mass or less, and even more preferably 35% by mass or less.

[0042] <Component (C): Water-soluble polymer> The bath solid composition of the present invention preferably further contains a water-soluble polymer as component (C) from the viewpoint of supporting component (A), improving the dissolution rate in bath water, and improving moldability. Examples of the water-soluble polymers include synthetic water-soluble polymers such as polyethylene glycol, polyvinylpyrrolidone, sodium polyacrylate, polyethyleneimine, and polyvinyl alcohol; natural water-soluble polymers such as glue, gelatin, collagen protein, casein, sodium alginate, carrageenan, ferceleran, tamarind gum, pectin, gum arabic, guar gum, xanthan gum, tragacanth gum, locust bean gum, dextrin, dextran, agar, and starch; and semi-synthetic water-soluble polymers such as carboxymethylcellulose, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, cellulose phthalate acetate, propylene glycol alginate, oxidized starch, esterified starch, etherified starch, and cationic starch; and one or more of these can be used. Among these, from the viewpoint of improving the dissolution rate in bath water and moldability, one or more selected from the group consisting of polyethylene glycol and dextrin is preferred as component (C), with polyethylene glycol being more preferred. The molecular weight of polyethylene glycol is preferably 4,000 to 20,000, and more preferably 5,000 to 15,000.

[0043] When component (C) is used, the content of component (C) in the bath solid composition is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, from the viewpoint of improving the dissolution rate in bath water and moldability. Furthermore, from the viewpoint of improving the moisturizing effect after bathing, the content is 85% by mass or less, preferably 80% by mass or less, and more preferably 75% by mass or less.

[0044] Furthermore, the total content of components (A), (B), and (C) in the solid bath composition is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and 100% by mass or less, from the viewpoint of facilitating the solidification of the composition, improving the rate of dissolution in bath water, suppressing foaming and oil floating in the bath water, and improving moisturizing feeling and moldability after bathing. Furthermore, while it is preferable that the bath solid composition of the present invention contains only components (A), (b1), and (C), it may also contain component (b2), which is a nonionic surfactant other than component (B), from the viewpoint of improving the dissolution rate in bath water and suppressing foaming and oil floating in the bath water. However, if the bath solid composition contains component (b2), its content is preferably 5% by mass or less, more preferably 2% by mass or less, of the bath solid composition.

[0045] <Dosage form, manufacturing method> The dosage form of the solid bath composition of the present invention is not particularly limited, but it is preferably granular from the viewpoint of solubility in bath water and ease of handling. The method for producing the bath solid composition is not particularly limited. For example, it can be produced by blending component (A), component (B), and other components as needed, heating, melting, stirring, mixing using known equipment, and then cooling and solidifying. When the dosage form is granular, it may be formed as granules, or it may be processed into granules by crushing or other means after solidification. When the dosage form of the solid bath composition of the present invention is granular, the particle size is preferably 0.5 mm or larger, more preferably 1 mm or larger, and preferably 3 mm or smaller, more preferably 2 mm or smaller, from the viewpoint of improving handling and improving the rate of dissolution in bath water. The bath solid composition of the present invention is preferably a solid composition obtained by heating component (A) and component (B) to a temperature above the melting point of the component with the higher melting point and mixing them. In the bath solid composition of the present invention, component (B) is thought to support component (A). As mentioned above, this is because the nonionic surfactant component (B) (component (b1)) forms molecular crystals at room temperature (25°C), and can support a large amount of oil in its voids. Furthermore, if the bath solid composition contains component (C), it is preferable that the bath solid composition be obtained by heating component (A), component (B), and component (C) to a temperature above the melting point of component (B) or component (C) which has a higher melting point, and then mixing them. If component (A) is a liquid oil, component (A) is supported on component (B) as a liquid oil; if component (A) is a solid oil, component (A) is supported on component (B) as a solid oil.

[0046] [Bath additive] The bath additive of the present invention contains the bath solid composition of the present invention described above. The bath additive of the present invention may consist solely of the bath solid composition, or it may also contain other components besides the bath solid composition, such as an organic acid and a carbonate. By including an organic acid and a carbonate in the bath additive, carbon dioxide effervescence can be imparted, and furthermore, the warming effect during bathing can be improved by the synergistic effect of carbon dioxide and component (A).

[0047] If the bath additive consists solely of the bath solid composition, the composition of the bath additive and its preferred embodiment are the same as those of the bath solid composition.

[0048] When a bath additive contains components other than the bath solid composition, the amount of the bath solid composition in the bath additive varies depending on the composition of the bath solid composition and the types of other components used, but is preferably 5% by mass or more and 95% by mass or less, and more preferably 10% by mass or more and 90% by mass or less. When a bath additive contains components other than the bath solid composition, the dosage form of the bath solid composition contained in the bath additive is preferably granular.

[0049] <Organic acid> Examples of organic acids include carboxylic acid compounds, organic sulfonic acid compounds, and organic phosphoric acid compounds. However, carboxylic acid compounds are preferred from the viewpoint of effervescence, solubility in bath water, and moldability of the bath additive. The carboxylic acid compound may be any compound having at least one carboxyl group, but a polyhydric carboxylic acid having two or more carboxyl groups is preferred from the viewpoint of imparting effervescence. Furthermore, the carboxylic acid compound may be either an aliphatic carboxylic acid or an aromatic carboxylic acid. Examples of aliphatic carboxylic acids include tartaric acid, malic acid, citric acid, maleic acid, glutaric acid, oxalic acid, fumaric acid, succinic acid, and adipic acid, while examples of aromatic carboxylic acids include benzoic acid, salicylic acid, and pyrrolidone carboxylic acid. Among the above, from the viewpoint of the effervescence of the bath additive, solubility in bath water, moldability, and economic efficiency, aliphatic carboxylic acids are preferred as organic acids, one or more selected from the group consisting of fumaric acid, succinic acid, and adipic acid are more preferred, one or more selected from the group consisting of fumaric acid and succinic acid are even more preferred, and the inclusion of fumaric acid is even more preferred.

[0050] When a bath additive contains an organic acid, the amount of organic acid in the bath additive is preferably 20% by mass or more, more preferably 30% by mass or more, from the viewpoint of improving effervescence, and preferably 50% by mass or less, from the viewpoint of improving the dissolution rate of the bath additive in the bath water.

[0051] <Carbonates> Examples of carbonates include dialkali metal carbonates such as sodium carbonate and potassium carbonate; alkali metal bicarbonates such as sodium bicarbonate and potassium bicarbonate; and alkaline earth metal carbonates such as calcium carbonate and magnesium carbonate. One or more of these can be used. From the viewpoint of improving the effervescence, solubility in bath water, and moldability of the bath additive, it is preferable that the carbonate be one or more selected from the group consisting of sodium carbonate, sodium bicarbonate, and calcium carbonate, more preferably one or more selected from the group consisting of sodium carbonate and sodium bicarbonate, and even more preferably containing sodium carbonate and sodium bicarbonate.

[0052] When a bath additive contains carbonate, the carbonate content in the bath additive is preferably 15% by mass or more, more preferably 20% by mass or more, from the viewpoint of improving foaming properties and moldability. Furthermore, from the viewpoint of improving the dissolution rate of the bath additive in bath water, it is preferably 50% by mass or less, more preferably 45% by mass or less.

[0053] When a bath additive contains organic acids and carbonates, the ratio of organic acids to carbonates in the bath additive is preferably 0.5 or more, more preferably 0.8 or more, and preferably 2.0 or less, and more preferably 1.5 or less, as a mass ratio [organic acid / carbonate], from the viewpoint of improving effervescence and improving the dissolution rate of the bath additive in bath water.

[0054] <Other ingredients> The bath additive of the present invention may contain, as appropriate, other components commonly used in bath additives. Examples of such components include anionic surfactants, nonionic surfactants other than component (B), or amphoteric surfactants; inorganic salts other than carbonates, such as sodium sulfate, magnesium sulfate, magnesium hydride, potassium chloride, sodium chloride, potassium nitrate, sodium nitrate, sodium polyphosphate, ammonium chloride, iron sulfate, sodium phosphate, and sodium thiosulfate; excipients other than component (C), such as calcium silicate and glucose; disintegrants; medicinal components such as herbal medicines; pigments; fragrances; and the like. Furthermore, the bath additive of the present invention may also contain the aforementioned water-soluble polymer component (C). The total content of the above-mentioned other components in the bath additive is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 12% by mass or less, from the viewpoint of facilitating the solidification of the composition, suppressing foaming of the bath water, and improving moldability.

[0055] <Dosage form, manufacturing method> From the viewpoint of improving handling, the bath additive of the present invention is preferably a solid bath additive. If the bath additive consists solely of the solid bath composition, the dosage form of the bath additive is preferably the same as that of the solid bath composition (granular).

[0056] Furthermore, if the bath additive of the present invention contains the aforementioned organic acid, carbonate, and / or other components, it is preferable to mix the bath solid composition with the organic acid, carbonate, and / or other components. Tablets are preferred as the dosage form (product form) of the bath additive containing the organic acid and carbonate. Tablets include compressed tablets, briquettes, and tablet formulations, with compressed tablets being more preferable from the viewpoint of moldability. In addition, if the bath additive of the present invention contains the aforementioned organic acid and carbonate, it is preferable to mix the granularly formed bath solid composition with the organic acid, carbonate, and other components. When the bath additive of the present invention is in the form of a tablet, briquette, or tablet dosage form, it can be manufactured using a press tablet press or briquette machine in accordance with conventional methods such as compression molding.

[0057] The bath additive of the present invention can be solidified while containing an oil, dissolves quickly in bath water, and provides a good moisturizing feeling after bathing. [Examples]

[0058] The present invention will be described below with reference to examples, but the present invention is not limited to the scope of these examples.

[0059] Examples 1-17, Comparative Examples 1-12 (Manufacturing and Evaluation of Solid Bath Compositions (Bath Additives)) After mixing the components shown in Tables 1-3, the mixture was heated to melt it, and the molten mixture, kept warm at 60°C, was poured into aluminum cups with a diameter of 2 cm and a height of 1 cm. It was then allowed to cool and solidify at room temperature (25°C) to produce a bath additive consisting of a solid bath composition. Furthermore, the appearance of the bath additive (whether it solidified or not), dissolution time in bath water, foaming of the bath water, oil floating on the bath water, and skin feel after bathing were measured and evaluated using the method described below. The results are shown in Tables 1-3. Note that the content (mass %) of each component shown in Tables 1-3 all represent the active amount.

[0060] <Appearance (Can it be solidified?)> The appearance and surface condition of the bath additive manufactured by the above method were observed and evaluated according to the following criteria. A rating of "B" or higher was considered acceptable for the solidification evaluation of the bath additive. AA: Solidifies in one phase, with no oil seepage and a smooth texture. A: It solidifies in one phase, and there is a slight oil seepage, but it has a smooth texture at the same level as an AA rating. B: It solidifies in one phase, but there is some oil seepage, and oil gets on your fingers, but it is still usable. C: It has solidified in phase 1, but there is oil seepage, the surface is sticky, and it is not at a practical level. D: It is not separated into two phases but is a single phase, and has not solidified. E: Separated into liquid and solid phases, or in a liquid state.

[0061] <Dissolution time in bath water> The bath additive manufactured by the above method was crushed into granules with a particle size of 2 mm or less. 0.5 g of this granule was added to 500 mL of 40°C bath water in a beaker and stirred at 200 rpm using a digital stirrer. The time it took for the bath additive to completely dissolve after being added to the bath water was measured and is shown in the table. A dissolution time of 5 minutes or less was considered to indicate a high dissolution rate and was deemed acceptable.

[0062] <Foaming of bathwater> After evaluating the "dissolution time in the bath water" as described above, the bath water was stirred again at 500 rpm for 30 seconds to create bubbles on the surface, and then left to stand for 3 minutes. The state of the bath water surface (liquid surface) after 3 minutes was visually observed and evaluated according to the following criteria. A rating of "C" or higher was considered acceptable. A: There are no bubbles on the liquid surface. B: There are a few bubbles around the rim of the beaker containing the bath water. C: Less than half of the liquid surface is covered with bubbles. D: The liquid surface is not completely covered, but more than half is covered with bubbles. E: The entire surface of the liquid is covered with bubbles.

[0063] <Oil floating on bathwater> After evaluating the "foaming of the bathwater" as described above, the surface (liquid level) of the bathwater with the bath additive completely dissolved was visually observed and evaluated according to the following criteria. A rating of "C" or higher is considered acceptable. AA: No oil residue A: There are a few oil droplets less than 1 mm in diameter. B: There are oil droplets with a diameter of 1-5 mm. C: There are oil droplets larger than 5 mm in diameter, but the proportion of oil occupying the liquid surface is less than 50%. D: Oil makes up more than 50% of the liquid surface.

[0064] <Skin feel after bathing> Ten grams of the bath additive manufactured using the method described above were added to 150 liters of bath water at 40°C. A panel of experts bathed for 10 minutes and evaluated the skin's feel (moisture level) after bathing according to the following criteria. A rating of "B" or higher was considered a passing grade. A higher rating indicates a greater moisturizing effect after bathing. AA:More moisturizing than A A: It becomes moist. B: Not as moist as A, but still acceptable. C: Not as moist as A, failing grade. D: Does not moisturize (same as plain hot water)

[0065] [Table 1]

[0066] [Table 2]

[0067] [Table 3]

[0068] Details of the ingredients listed in the table are as follows. *1: Tri(caprylic / capric acid) glyceryl, manufactured by Kao Corporation in "Coconard MT" *2: Octyldodecyl myristate, manufactured by Kao Corporation as "Excepearl O-DM" *3: Isopropyl palmitate, manufactured by Kao Corporation as "Excepearl IPP" *4: Dimethicone, manufactured by Shin-Etsu Chemical Co., Ltd., "KF-96A 10CS" *5: Liquid paraffin, "Highcall K-230" manufactured by Kaneda Co., Ltd. *6: POE(23) lauryl ether, manufactured by Kao Corporation as "Emulgen 123P", melting point 34℃ *7: POE(20) cetyl ether, EMALEX 120 manufactured by Nippon Emulsion Co., Ltd., freezing point 42°C *8: POE(15) stearyl ether, EMALEX 615 manufactured by Nippon Emulsion Co., Ltd., melting point 41℃ *9: POE(30) stearyl ether, EMALEX 630 manufactured by Nippon Emulsion Co., Ltd., freezing point 46°C *10: POE(20) behenyl ether, "EMALEX BHA20" manufactured by Nippon Emulsion Co., Ltd., melting point 52℃ *11: POE(6) stearyl ether, manufactured by Kao Corporation as "Emulgen 306P", melting point 31℃ *12: POE(40) sorbitol tetraoleate, manufactured by Kao Corporation as "Leodol 440V", freezing point -20℃ *13: Polyethylene glycol, "K-PEG6000LA" manufactured by Kao Corporation, molecular weight 7300-9300

[0069] Tables 1 and 2 show that the bath additive of this embodiment is superior in terms of appearance, dissolution rate in bath water, foaming of the bath water, low oil residue, and skin feel after bathing. In contrast, the bath additive of the comparative example shown in Table 3 showed inferior performance in one or more of the above evaluation items.

[0070] Examples 18-21, Comparative Examples 13-15 (Manufacturing and Evaluation of Carbonated Effervescent Bath Additives) The bath solid composition shown in Table 4 and the other components were mixed in the proportions indicated in the table. The mixture was then compressed and molded at a pressure of 10.0 N using a press tablet machine to produce 40 g tablets (tablet-type carbonated effervescent bath additives). Furthermore, the appearance of the tablets, the rate of dissolution in bath water, and the skin feel after bathing were evaluated using the method described below. The results are shown in Table 4. Note that the content (mass %) of each component shown in Table 4 all represent the active amount.

[0071] <Appearance of the tablet> The appearance of the bath additive (tablets) manufactured by the above method was observed and evaluated according to the following criteria. A rating of "C" or higher was considered acceptable. A: There is no oil seepage, and the appearance is good. B: There is almost no oil seepage, and the appearance is good. C: There is some oil seepage, but the appearance is good. D: There is oil seepage, resulting in a defective appearance.

[0072] <Speed ​​of dissolution in bath water> One bath additive tablet prepared by the method described above was added to 150 liters of 40°C bathwater. The time it took for the bath additive to completely dissolve was measured and evaluated according to the following criteria. A rating of "C" or higher was considered acceptable. A: The bath salts will dissolve completely within 10 minutes. B: The bath salts dissolve completely within 15 minutes. C: The bath additive dissolves completely within 20 minutes. D: The bath salts do not dissolve after 20 minutes.

[0073] <Skin feel after bathing> One bath additive tablet manufactured using the method described above was added to 150 liters of bath water at 40°C. A panel of experts bathed for 10 minutes and evaluated the skin's feel (moisture level) after bathing according to the following criteria. A rating of "C" or higher was considered acceptable. A: It is more moist than B. B: Moisturizing C: Not as moist as B, but still acceptable. D: Does not moisturize (same as plain hot water)

[0074] [Table 4] [Industrial applicability]

[0075] According to the present invention, it is possible to provide a solid bath composition that contains an oil agent but can be solidified, dissolves quickly in bath water, reduces foaming and oil separation in the bath water, and provides a good moisturizing feeling after bathing.

Claims

1. The following components (A) to (C): (A) Oil (B) Polyoxyethylene alkyl ether (C) Water-soluble polymer A solid bath composition containing, The average number of ethylene oxides added to the polyoxyethylene alkyl ether is 15 or more. The aforementioned component (A) is one or more selected from the group consisting of silicone oil, ester oil, and hydrocarbon oil. The aforementioned component (C) is at least one selected from polyethylene glycol, polyvinylpyrrolidone, sodium polyacrylate, polyethyleneimine, polyvinyl alcohol, natural water-soluble polymers, and semi-synthetic water-soluble polymers. The content of component (A) relative to the total content of component (A), component (B), and component (C) is 7% by mass or more and 30% by mass or less. The content of component (B) relative to the total content of component (A), component (B), and component (C) is less than 20% by mass. The content of component (C) relative to the total content of component (A), component (B), and component (C) is 85% by mass or less. The mass ratio (A) / (B) of component (A) to component (B) is 0.20 or more and 4.0 or less. A solid bath composition in which the total content of component (A) and component (B) relative to the total content of component (A), component (B), and component (C) is 25% by mass or more.

2. The bath solid composition according to claim 1, wherein the component (A) is an ester represented by the following general formula (3). R 5 - (OCOR 6 ) p (3) In general formula (3), R 5 represents a polyhydric alcohol residue, R 6 represents a monohydric carboxylic acid residue having 1 to 25 carbon atoms, and p represents an integer between 2 and 10.

3. A bath additive containing the bath solid composition described in claim 1 or 2.

4. The bath additive according to claim 3, further containing an organic acid and a carbonate.

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