Compression-molded bath additive

Abstract

To provide a compression-molded bath additive that improves the feel of the bathwater, extends the dissolution time, and suppresses discoloration of the bathtub when added to the bathwater. [Solution] A compression-molded bath additive containing (A) carbonate, (B) organic acid, (C) dye, and (D) nonionic surfactant, wherein the content of (A) carbonate is 70% by mass or more.

Description

[Technical Field]

[0001] This invention relates to a compression-molded bath additive. [Background technology]

[0002] In recent years, it has become common to add bath additives to bathwater to enhance its fragrance and color, to improve bathing comfort, to stimulate metabolism and alleviate cold sensitivity, and to obtain the benefits of a warm bath. Various forms of bath additives are sold, including bath salts, tablets, and liquids. Among these, bath additives containing carbon dioxide-generating compounds, which combine carbonates and acids, are particularly popular. These compounds generate carbon dioxide in the bathwater, and the dissolved carbon dioxide expands capillaries, promoting metabolism and offering benefits such as improved blood circulation and fatigue recovery.

[0003] Various types of effervescent bath additives have been studied. For example, Patent Document 1 proposes a solid bath additive containing (A) a carbonate and (B) an organic acid including fumaric acid (B1) and tartaric acid (B2), wherein the mass ratio of component (B2) to component (B1) [(B2) / (B1)] is 0.01 or more and 1.3 or less, the total amount of component (B1) and component (B2) in component (B) is 80% by mass or more, and the total amount of component (B1) and component (B2) in the solid bath additive is 35% by mass or more. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-132574 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In recent years, there has been a demand for bath additives that improve the feel of the bathwater when dissolved. To improve the feel of the bathwater, one approach is to increase the carbonate content to make the bathwater alkaline. Alkaline bathwater has a thicker consistency, making it more compatible with the skin and improving the feel of the water. In addition, a higher carbonate content extends the dissolution time, allowing for a longer period of effervescence.

[0006] On the other hand, as a type of effervescent bath additive that combines carbonate and acid, compressed bath additives, such as tablets, have become popular. These are compressed into solid forms, such as tablets, so that they sink in the bathwater, making it easier for the generated carbon dioxide gas to dissolve into the bathwater. When a compressed bath additive is added to the bathwater, it sinks and remains at the bottom of the tub, remaining in contact with the bottom until its density becomes lighter than that of water. Bath additives sometimes contain dyes to color the bathwater, but with compressed bath additives that remain at the bottom of the tub for a long time, the dissolved dyes can stain the bottom of the tub. Increasing the carbonate content will increase the dissolution time, which in turn increases the contact time with the bottom of the tub, potentially leading to a stronger staining of the bottom of the tub in contact with the compressed bath additive.

[0007] Therefore, the object of the present invention is to provide a bath additive that improves the feel of the bathwater, extends the dissolution time, and suppresses discoloration of the bathtub when added to the bathwater, in the form of a compression-molded bath additive. [Means for solving the problem]

[0008] As a result of diligent research, the inventors have discovered that the above problems can be solved by using a compression-molded bath additive containing carbonate, organic acid, and dye, with the carbonate content at 70% by mass or more, and by further including a nonionic surfactant, thus completing the present invention.

[0009] The present invention is summarized in the following (1) to (4). (1) The following components (A) to (D): (A) Carbonate (B)Organic acid (C) Pigment (D) Nonionic surfactant comprising A compression-molded bath agent, wherein the content of said (A) carbonate is 70% by mass or more. (2) The compression-molded bath agent according to (1), which has a weight of 80 g or more. (3) The compression-molded bath agent according to (1) or (2), which is effervescent. (4) A method for preventing adhesion of said (C) dye to a bathtub, comprising incorporating (D) a nonionic surfactant into a compression-molded bath agent that comprises (A) a carbonate, (B) an organic acid and (C) a dye, wherein the content of said (A) carbonate is 70% by mass or more.

Effect of the Invention

[0010] According to the present invention, staining of a bathtub with a dye can be suppressed even for a compression-molded bath agent that has a long dissolution time and thus remains in contact with the bathtub for a long time. Furthermore, since the carbonate content is 70% by mass or more, bath water can be made alkaline, and the feel of the bath water can be improved.

Brief Description of Drawings

[0011] [Figure 1] It is a schematic diagram for explaining the test method of Evaluation Test 1, wherein Fig. 1(a) is a top view of a bathtub used for the test, and Fig. 1(b) is an enlarged view of portion Ib in (a). [Figure 2] It is a graph showing the staining test results of Evaluation Test 1. [Figure 3] It is a graph showing the staining test results of Evaluation Test 1.

Mode for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described in more detail.

[0013] (Compression-molded Bath Agent) The compression-molded bath additive according to an embodiment of the present invention contains (A) carbonate, (B) organic acid, (C) dye, and (D) nonionic surfactant, wherein the content of (A) carbonate is 70% by mass or more. By making it a compression-molded formulation, the bath additive can be submerged in the bathwater, and the generated carbon dioxide gas dissolves more easily into the bathwater, thereby enhancing the effervescence effect. In addition, the content of (A) carbonate is 70% by mass or more, which makes the bathwater alkaline, improving the feel of the water while extending the dissolution time of the compression-molded bath additive, and the inclusion of (D) nonionic surfactant suppresses the adhesion of dye to the bathtub due to contact between the compression-molded bath additive and the bathtub.

[0014] <Ingredient (A): Carbonate> Carbonates are components that can produce carbon dioxide gas through a reaction with organic acids. Any carbonate that reacts with an organic acid in liquid to produce carbon dioxide gas can be used, such as sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, calcium carbonate, potassium carbonate, and magnesium carbonate. One or more of these can be used. Among these, sodium carbonate and sodium bicarbonate are preferred, and using them in combination is even more preferable.

[0015] The particle size of the carbonate (the average particle size [median diameter 50] that gives 50% of the cumulative distribution) is preferably 0.03 to 1 mm, and more preferably 0.05 to 0.5 mm. Within this range, the compression-molded bath additive will have an appropriate hardness and the dissolution time can be sustained.

[0016] The carbonate content in 100% by mass of the compression-molded bath additive is 70% by mass or more. When the carbonate content is 70% by mass or more, it reacts with organic acids to generate carbon dioxide gas and makes the bathwater alkaline. From the viewpoint of extending the dissolution time, the carbonate content is preferably 75% by mass or more, more preferably 77% by mass or more, and even more preferably 80% by mass or more. Furthermore, from the viewpoint of suppressing undissolved residue in the bathwater and improving visibility by increasing the amount of foam generated during dissolution, it is preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 83% by mass or less.

[0017] <Component (B): Organic acid> Examples of organic acids include succinic acid, fumaric acid, malic acid, adipic acid, tartaric acid, benzoic acid, citric acid, and salicylic acid. These organic acids can be used individually or in appropriate combinations of two or more. Among these, succinic acid and fumaric acid are preferred from the viewpoint of solubility in bath water and suppressing adverse effects on the material of the bathtub surface and piping.

[0018] The particle size of the organic acid (average particle size [median diameter 50] that gives 50% of the cumulative distribution) is preferably 0.03 to 1 mm, and more preferably 0.05 to 0.5 mm, from the viewpoint of tabletability, granulation, solubility, and oil absorption capacity. When the particle size of the organic acid is within the above range, undissolved particles are less likely to occur in the liquid, and it can react efficiently with carbonates.

[0019] Furthermore, if the particle size of the organic acid is larger than the particle size indicated above, it is preferable to crush it beforehand until it reaches a suitable particle size. Examples of crushers that can be used for crushing include impact crushers such as hammer crushers, atomizers, impact crushers such as pin mills, and shear crushers such as flash mills. These may be operated in a single stage or in a multi-stage operation using the same or different types of crushers.

[0020] The organic acid content in 100% by mass of the compression-molded bath additive is preferably 9 to 25% by mass. If the organic acid content is 9% by mass or more, sufficient carbon dioxide can be generated when it reacts with carbonates to produce carbon dioxide. The organic acid content is more preferably 10% by mass or more, and even more preferably 12% by mass or more. Furthermore, from the viewpoint of extending the dissolution time and maintaining the alkalinity of the bathwater, the organic acid content is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 18% by mass or less.

[0021] Furthermore, in this embodiment of the compression-molded bath additive, the content of component (A) carbonate relative to component (B) organic acid ((A) / (B)) is preferably 1 to 10 by mass ratio. When the content of carbonate (component (A)) is 1 to 10 for every 1 part of organic acid (component (B)), undissolved residue in the bathwater can be suppressed. In addition, from the viewpoint of providing a good feel in the bathwater, improving the visibility of effervescence over a long period of time during bathing due to the longer dissolution time, and enjoying the sensation of bubbles produced by effervescence, the (A) / (B) (mass ratio) is more preferably 2 to 8, and even more preferably 4 to 6.

[0022] <Component (C): Pigment> Examples of pigments include azo pigments, xanthene pigments, triphenylmethane pigments, anthraquinone pigments, quinoline pigments, indigo pigments, nitro pigments, nitroso pigments, pyrene pigments, and phthalocyanine pigments. The following pigments are preferred.

[0023] Examples of azo dyes include azo dyes that do not contain carboxyl groups and sulfone groups, such as Red 221, Red 225, Red 228, Red 404, Red 501, Red 505, Yellow 205, Yellow 401, Yellow 404, Orange 203, Orange 401, Orange 403; Red 2, Red 102, Red 201, Red 202, Red 203, Red 204, Red 205, Red 206, Red Examples include azo dyes containing carboxyl groups and / or sulfone groups, such as Red No. 207, Red No. 208, Red No. 219, Red No. 220, Red No. 227, Red No. 405, Red No. 502, Red No. 503, Red No. 504, Red No. 506, Yellow No. 5, Yellow No. 406, Orange No. 205, Orange No. 402, Brown No. 201, and Black No. 401; and pyrazolone-based azo dyes, such as Yellow No. 4, Yellow No. 402, Yellow No. 407, and Orange No. 204.

[0024] Examples of xanthene pigments include Red No. 3, Red No. 104 (1), Red No. 105 (1), Red No. 106, Red No. 213, Red No. 214, Red No. 215, Red No. 218, Red No. 223, Red No. 230 (1), Red No. 230 (2), Red No. 231, Red No. 232, Red No. 401, Yellow No. 201, Yellow No. 202 (1), Yellow No. 202 (2), Orange No. 201, Orange No. 206, Orange No. 207, and so on.

[0025] Examples of triphenylmethane-based dyes include Blue No. 1, Blue No. 202, Blue No. 203, Blue No. 205, Green No. 3, Green No. 205, and Green No. 402.

[0026] Examples of anthraquinone dyes include anthraquinone dyes that do not contain sulfone groups, such as Blue 204, Blue 403, Green 202, and Violet 201; and anthraquinone dyes that contain sulfone groups, such as Green 201 and Violet 401.

[0027] Examples of quinoline-based dyes include Yellow 203 and Yellow 204.

[0028] Examples of indigo-based dyes include Blue No. 2, Blue No. 201, and Red No. 226.

[0029] Examples of nitro-based dyes include (1) Yellow 403.

[0030] Examples of nitroso dyes include Green No. 401.

[0031] Examples of pyrene-based dyes include Green No. 204.

[0032] An example of a phthalocyanine-based dye is Blue No. 404.

[0033] In addition to the pigments mentioned above, chlorophyll, riboflavin, annat, anthocyanins, etc. may also be used.

[0034] Among the above-mentioned dyes, azo dyes, xanthene dyes, and triphenylmethane dyes are preferred from the viewpoint that nonionic surfactants can effectively suppress the staining of the bathtub by the dyes, and azo dyes, xanthene dyes, and triphenylmethane dyes containing carboxyl groups and / or sulfone groups are more preferred, with Red No. 102, Red No. 227, Red No. 106, Blue No. 1, and Yellow No. 4 being particularly preferred. These dyes can be used individually or in appropriate combinations of two or more.

[0035] The pigment content in 100% by mass of the compression-molded bath additive is preferably 0.0005 to 0.5% by mass. If the pigment content is 0.0005% by mass or more, the compression-molded bath additive and the bath water can be colored, and if it is 0.5% by mass or less, the desired color can be appropriately achieved. The pigment content is more preferably 0.001% by mass or more, and even more preferably 0.005% by mass or more. Furthermore, from the viewpoint of suppressing coloring of the bathtub surface material, the pigment content is more preferably 0.4% by mass or less, even more preferably 0.3% by mass or less, and particularly preferably 0.2% by mass or less.

[0036] <Ingredient (D): Nonionic surfactant> In this invention, a nonionic surfactant is included as an ingredient that suppresses the adhesion of pigments to the bathtub. The mechanism by which the nonionic surfactant can suppress the adhesion of pigments to the bathtub when the compression-molded bath additive comes into contact with the bathtub is not clear, but it is presumed that even if pigments adhere to the surface of the bathtub, the cleaning effect of the nonionic surfactant makes it easier to remove the colored pigments from the surface of the bathtub.

[0037] Nonionic surfactants include, for example, sucrose fatty acid esters; polyoxyethylene fatty acid esters such as polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene monooleate, polyethylene glycol distearate, polyethylene glycol dioleate, and polypropylene glycol dioleate; sorbitan fatty acid esters such as sorbitan monocaprylate, sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, sorbitan distearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, and sorbitan monosesquioleate; and polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan triisostearate. Examples include polyoxyethylene sorbitan fatty acid esters; polyoxyethylene dodecyl ether (polyoxyethylene lauryl ether), polyoxyalkylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyalkylene tridecyl ether, polyoxyethylene myristyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene behenyl ether, polyoxyethylene-2-ethylhexyl ether, polyoxyethylene isodecyl ether, and other polyoxyethylene alkyl ethers; polyoxyethylene alkylphenol ethers such as polyoxyethylene styrene-phenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene disstyrene-phenyl ether, polyoxyethylene tripenzylphenyl ether, and other polyoxyethylene alkylphenol ethers; glycerin fatty acid esters such as glycerin monostearate and glycerin monooleate; and polyoxyethylene hydrogenated castor oil and polyoxyethylene castor oil. These nonionic surfactants can be used individually or in appropriate combinations of two or more types.

[0038] Among these, sucrose fatty acid esters and polyoxyethylene fatty acid esters are preferred, and sucrose fatty acid esters, polyoxyethylene monolaurate, polyoxyethylene monostearate, and polyoxyethylene monooleate are more preferred.

[0039] The content of nonionic surfactant in 100% by mass of the compression-molded bath additive is preferably 0.01 to 5% by mass. If the content of nonionic surfactant is 0.01% by mass or more, the discoloration of the bathtub can be suppressed, and if it is 5% by mass or less, unwanted foaming will not occur when the compression-molded bath additive is added to the bathwater. The content of nonionic surfactant is more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, even more preferably 4% by mass or less, even more preferably 3.5% by mass or less, and particularly preferably 3% by mass or less.

[0040] Furthermore, in the compression-molded bath additive of this embodiment, the content of component (C) dye to component (D) nonionic surfactant ((C) / (D)) is preferably 0.0001 to 50 by mass ratio. When the content of dye (component (C)) is 0.0001 or more per 1 part of nonionic surfactant (component (D)), the dye disperses easily in the bathwater, and when it is 50 or less, an effect of suppressing the adhesion of the dye to the bathtub is obtained. The (C) / (D) (mass ratio) is more preferably 0.005 to 20, and even more preferably 0.01 to 4.

[0041] Furthermore, preferred combinations of component (C) dye and component (D) nonionic surfactant include, for example, azo dyes, xanthene dyes, and triphenylmethane dyes, sucrose fatty acid esters and / or polyoxyethylene fatty acid esters.

[0042] <Other ingredients> The compression-molded bath additive of this embodiment may contain, as appropriate, components other than those described above (A) to (D), within a range that does not impair the effects of the present invention. Other components may include, for example, fragrances, inorganic salts, sugars, lubricants, binders, humectants, clouding agents, surfactants other than nonionic surfactants, enzymes, pigments and minerals, vitamins and their derivatives, anti-fading agents, pH adjusters, disinfectants, etc. The uses of these other components may overlap.

[0043] Fragrances include natural fragrances extracted from various plants and animals, synthetic fragrances that are chemically synthesized, and blended fragrances made by mixing many of these fragrance components. These fragrances can be used individually or in any combination of two or more to form a blended fragrance. Furthermore, the fragrances can also be used as a mixture (fragrance composition) containing fragrance components, solvents, fragrance stabilizers, etc.

[0044] Examples of solvents for fragrances include water, alcohols such as ethanol, propanol, and benzyl alcohol, polyhydric alcohols such as ethylene glycol, diethylene glycol, dipropylene glycol, glycerin, and 1,3-butanediol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, and dipropylene Examples of solvents include glycol monomethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monobutyl ether, propylene glycol monopropyl ether, dipropylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monobutyl ether, dipropylene glycol dimethyl ether, glycol ethers such as phenyl carbitol, phenyl cellosolve, and benzyl carbitol; paraffins such as liquid paraffin and n-paraffin; esters such as diethyl phthalate, benzyl benzoate, triethyl citrate, and isopropyl myristate; and others such as 3-methyl-4-methoxybutanol, N-methylpyrrolidone, and propylene carbonate. These solvents can be used individually or in any combination of two or more. They can also be mixed with the above fragrance components and used as a fragrance composition.

[0045] The fragrance content in 100% by mass of the compression-molded bath additive is preferably 0.1 to 2% by mass, and more preferably 0.3 to 1% by mass.

[0046] Inorganic salts include any components other than the carbonates mentioned above, such as chlorides like sodium chloride, potassium chloride, and ammonium chloride; sulfates like sodium sulfate, aluminum sulfate, iron sulfate, potassium aluminum sulfate, sodium thiosulfate, calcium thiosulfate, potassium thiosulfate, and sodium hyposulfite; nitrates like sodium nitrate, potassium nitrate, and calcium nitrate; phosphates like sodium phosphate, sodium polyphosphate, and calcium hydrogen phosphate; silicates like calcium silicate and magnesium silicate; sulfides like sulfur, calcium sulfide, sodium sulfide, potassium sulfide, ammonium sulfide, barium sulfide, zinc sulfide, tin sulfide, antimony sulfide, iron sulfide, and phosphorus sulfide; silicon compounds like anhydrous silicic acid, metasilicic acid, mica powder, and neutral clay; hydroxides like sodium hydroxide and calcium hydroxide; and borax, boric acid, calcium oxide, potassium bromide, potassium permanganate, artificial callus salts, mineral springs, mineral sand, and mineral deposits. These inorganic salts can also be included as bulk adjusters, formulation aids, and formulation stabilizers.

[0047] The inorganic salt content in 100% by mass of the compression-molded bath additive is preferably 0 to 20% by mass, more preferably 0.1 to 17% by mass, and even more preferably 0.2 to 15% by mass. Within this range, the compression-molded bath additive can have excellent moldability and good solubility.

[0048] Examples of sugars include glucose, fructose, lactose, maltose, sucrose, maltodextrin, cyclodextrin, maltose, fructose, and trehalose.

[0049] The sugar content in 100% by mass of the compression-molded bath additive of this embodiment is preferably 0.1 to 15% by mass, more preferably 0.3 to 10% by mass, and even more preferably 0.5 to 3% by mass. Within this range, the compression-molded bath additive can have excellent shape retention and good solubility.

[0050] Examples of lubricants include talc, kaolin, magnesium stearate, calcium stearate, stearic acid, and silicone oil. The compression-molded bath additive of this embodiment can improve release properties during tableting and increase production efficiency by incorporating a lubricant.

[0051] The lubricant is preferably contained in an amount of 0.001 to 1.0% by mass, and more preferably 0.01 to 0.5% by mass, relative to 100% by mass of the compression-molded bath additive. By keeping the amount within this range, the fluidity of the powder can be improved when mixing the raw materials.

[0052] Examples of binders include polyalkylene glycol, polyvinylpyrrolidone, and dextrin. Among these, polyalkylene glycol is preferred. The molecular weight of the polyalkylene glycol is preferably 100 to 20,000, more preferably 400 to 15,000, and even more preferably 2,000 to 10,000. Specifically, polyethylene glycol, polypropylene glycol, etc., are used, with polyethylene glycol being particularly preferred. Various polyalkylene glycols can also be used individually or in combination of two or more. The dissolution time of the compression-molded bath additive can be adjusted by including a binder. For example, the dissolution time can be lengthened by increasing the amount of binder added.

[0053] The binder content in 100% by mass of the compression-molded bath additive is preferably 0.1 to 10% by mass, more preferably 0.3 to 5% by mass, and even more preferably 0.5 to 3% by mass. Within this range, the compression-molded bath additive has excellent shape retention and the dissolution time of the compression-molded bath additive can be adjusted.

[0054] Examples of moisturizers include ceramides such as ceramides, ceramide derivatives, and ceramide-like substances; organic acid salts such as sodium lactate, disodium tartrate, sodium pyrrolidone carboxylate, and disodium glutamate; mucopolysaccharides such as chondroitin sulfate and hyaluronic acid; plant collagen obtained from soybeans, corn, and carrots; marine collagen obtained from salmon, pufferfish, tuna, and flounder; fatty acid esters such as isopropyl myristate and isopropyl palmitate; shea butter, squalane, placenta, arbutin, casein, silk, honey, jojoba oil, ginger extract, kudzu extract, and cationized cellulose.

[0055] Examples of clouding agents include titanium dioxide.

[0056] Examples of surfactants other than nonionic surfactants include anionic surfactants such as fatty acid esters for soap base, sodium α-olefin sulfonate, sodium alkyl glucoside sulfate, sodium lauryl sulfate, sodium polyoxyethylene lauryl sulfate, and sodium coconut oil fatty acid methyl taurate; amphoteric surfactants such as alkyl betaine, alkylamidopropyl betaine, alkylamidosulfobetaine, and 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine; and cationic surfactants such as alkylamine salts and quaternary ammonium salts.

[0057] Examples of enzymes include trypsin, α-chymotrypsin, bromelain, papain, protease, productase, serrathiopeptidase, lysozyme, pepsin, and ficin.

[0058] Examples of pigments and minerals include clay, red iron oxide, yellow iron oxide, mica, zinc oxide, bentonite, zeolite, metasilicic acid, acid clay, and their coated granules. These can also be included as formulation aids.

[0059] Examples of vitamins and their derivatives include vitamin A, vitamin B, vitamin C, vitamin D, vitamin E, vitamin F, vitamin H, pantothenic acid, nicotinic acid or its derivatives, vitamin E nicotinic acid ester, tocopherol acetate, sodium ascorbate, and the like.

[0060] Examples of color-fastening agents include glycine, alanine, amino acids such as glutamic acid, and their salts.

[0061] Examples of pH adjusting agents include disodium hydrogen citrate and trisodium citrate.

[0062] Examples of disinfectants include isopropylmethylphenol, triclosan, dichloroisocyanuric acid, silver zeolite, cetylpyridinium chloride, benzalkonium chloride, benzethonium chloride, chlorhexidine, hinokitiol, phenol, glycyrrhizinate and its derivatives.

[0063] (Method of manufacturing compression-molded bath additives) The compression-molded bath additive of this embodiment can be manufactured by mixing the above components (A) to (D) and optionally any other components and then compression molding them. When compression molding is performed, the method is not particularly limited as long as a compression-molded bath additive, such as tablets, can be obtained, and a known tablet press can be used.

[0064] A tablet press is a device that fills a die with a powder mixture and compresses and shapes it between a lower punch and an upper punch. There are two types of tablet presses: single-shot tablet presses, in which a pair of upper and lower punches move up and down to compress the tablet within a single die, and rotary tablet presses, in which die sets are embedded at equal intervals around the outer circumference of a horizontally rotating turntable, and a series of operations—filling, compressing, and discharging—are performed continuously as the turntable rotates.

[0065] The compression pressure when using a tablet press is not particularly limited and can be adjusted as appropriate according to the size, thickness, density, etc., of the compression-molded bath additive. A higher compression pressure results in a longer dissolution time for the resulting compression-molded bath additive. Conversely, a lower compression pressure results in a shorter dissolution time for the resulting compression-molded bath additive. For example, from the viewpoint of moldability, it is preferable to compress the tablets at a pressure of 10 to 50 tons, more preferably 15 to 45 tons, and even more preferably 20 to 40 tons. Compressing tablets at a pressure of 10 tons or more prevents the tablets from becoming brittle, making them less prone to cracking or chipping during line transport or transportation. Furthermore, if the compression pressure is 50 tons or less, capping is less likely to occur, making the tablets less prone to chipping during line transport or transportation.

[0066] Furthermore, the compression molding method should not be restricted, and it can be manufactured by direct powder compression (direct compression method) or granular compression (indirect compression method). In addition, the order and method of mixing each component can be selected as appropriate.

[0067] (Physical properties of compression-molded bath additives) The compression-molded bath additive of this embodiment preferably has a maximum diameter of 50 mm or more, more preferably 60 mm or more, and even more preferably 70 mm or more. A maximum diameter of 50 mm or more allows for a larger amount of carbon dioxide gas to be generated per unit time. Furthermore, the upper limit of the maximum diameter is preferably 80 mm or less, and more preferably 75 mm or less. A maximum diameter of 80 mm or less helps to suppress cracking and chipping of the bath additive during line transport and transportation. Note that the maximum diameter refers to the diameter of the circumscribed circle when viewing the compression-molded bath additive from the axial direction.

[0068] In this embodiment, the compression-molded bath additive preferably has a thickness of 13 mm or more, more preferably 15 mm or more, even more preferably 17 mm or more, and also preferably 30 mm or less, more preferably 25 mm or less, and even more preferably 22 mm or less, from the viewpoint of suppressing cracking or chipping of the bath additive during line transport or transportation.

[0069] The compression-molded bath agent of the present embodiment preferably has a weight of 80 g or more. Although the weight is not particularly limited, for example, when the weight is 80 g or more, the bath agent contains 56 g or more of the carbonate as component (A), which makes it easy to alkalinize bath water. Furthermore, it is possible to increase the amount of carbon dioxide gas generated per unit time, prolong the dissolution time, and sustain foaming over a long period of time. The weight of the compression-molded bath agent is more preferably 90 g or more, still more preferably 100 g or more. From the viewpoint of suppressing cracking and chipping of the bath agent during line conveyance and transportation, the weight is preferably 200 g or less, more preferably 170 g or less, and still more preferably 150 g or less.

[0070] The compression-molded bath agent of the present embodiment has a density of 1.3 g / cm 3 or higher, which is preferable, and more preferably 1.6 g / cm 3 or higher, and further preferably 2.5 g / cm 3 or lower, more preferably 2.0 g / cm 3 or lower. When the density falls within the above range, cracking and chipping of the compression-molded bath agent during transportation can be suppressed. In addition, since an appropriate foaming amount can be achieved, it is possible to increase the amount of carbon dioxide gas generated per unit time and sustain foaming over a long period of time.

[0071] From the viewpoint that the compression-molded bath agent of the present embodiment can increase the amount of carbon dioxide gas generated per unit time and sustain foaming over a long period of time, the volume thereof is 40000 mm 3 or higher, which is preferable, and more preferably 50000 mm 3 or higher. In addition, since cracking and chipping of the bath agent during line conveyance and transportation can be suppressed, the volume is preferably 100000 mm 3 or less, more preferably 90000 mm 3 or less, and still more preferably 80000 mm 3 or less.

[0072] In this embodiment, when the compression-molded bath additive is added to 10 liters of 40°C water, it is preferable that the time from the start of dissolution to the end of dissolution is 250 seconds or more. If the foaming continues for 250 seconds or more, the texture of the water due to the foaming is improved, resulting in a good user experience. The dissolution time is more preferably 250 to 900 seconds, even more preferably 270 to 900 seconds, particularly preferably 300 to 800 seconds, and most preferably 350 to 750 seconds.

[0073] (Method to prevent staining of bathtubs) The present invention also provides a method for preventing the adhesion of (C) pigment to a bathtub by including (D) a nonionic surfactant in a compression-molded bath additive containing (A) a carbonate, (B) an organic acid, and (C) a pigment, wherein the content of (A) the carbonate is 70% by mass or more. By adding the nonionic surfactant component (D), in a compression-molded bath additive containing 70% by mass or more of the carbonate component (A), the dissolution time is increased, and even if the compression-molded bath additive is in contact with the bathtub (specifically, the bottom of the bathtub) for a longer period, the staining of the bathtub by the pigment component (C) can be suppressed.

[0074] Specific examples of each component, preferred components, their amounts, and the manufacturing method of the compression-molded bath additive are as described above.

[0075] The material of the bathtub surface to which the method for preventing pigment adhesion to the bathtub of this embodiment is applied is not particularly limited, but examples include FRP (fiber-reinforced plastic), resins such as acrylic and polyester, stainless steel, marble, wood, and enamel. In particular, since pigments are difficult to remove once they adhere to resin, the method for preventing pigment adhesion to the bathtub of this embodiment is suitable for bathtubs whose surfaces are made of resin. [Examples]

[0076] The present invention will be described in more detail below using examples, but the present invention is not limited to these.

[0077] (Examples 1-19, Comparative Examples 1-7) The components were uniformly mixed according to the compositions shown in Tables 1 to 3 to obtain a powder mixture. This powder mixture was compressed into tablets using a hydraulic tablet press to produce cylindrical, compression-molded bath additives with a diameter of 70 mm and a total weight of 100 g.

[0078] The nonionic surfactants used in each example are as follows: • Polyoxyethylene monolaurate: "Nonion L-2" manufactured by NOF Corporation • Polyoxyethylene monooleate 1: "Nonion O-2" manufactured by NOF Corporation • Polyoxyethylene monooleate 2: "Nonion O-6" manufactured by NOF Corporation • Polyoxyethylene monostearate 1: "Nonion S-2" manufactured by NOF Corporation • Polyoxyethylene monostearate 2: "Nonion S-6" manufactured by NOF Corporation • Polyoxyethylene monostearate 3: "Nonion S-40" manufactured by NOF Corporation • Sucrose fatty acid ester 1: "Surfhope SE COSME C-1811" manufactured by Mitsubishi Chemical Corporation • Sucrose fatty acid ester 2: "Ryoto Sugar Ester S-770" manufactured by Mitsubishi Chemical Corporation. • Sucrose fatty acid ester 3: "Surfhope SE COSME C-1803" manufactured by Mitsubishi Chemical Corporation

[0079] [Table 1]

[0080] [Table 2]

[0081] [Table 3]

[0082] The following evaluation tests 1 to 3 were performed using the compression-molded bath additives of Examples 1 to 19 and Comparative Examples 1 to 7 prepared above. The bathtub used in the test was the "Cradle Bathtub FRP Bath" manufactured by TOTO Ltd. (product number: YYT9W, material: FRP, internal dimensions: depth 68cm, width 46cm, length 110cm).

[0083] <Evaluation Test 1: Coloring Test> The coloring test involved two test patterns: Test Pattern A, in which the compression-molded bath additive was placed in the bathtub before adding bathwater, and Test Pattern B, in which the compression-molded bath additive was added to the bathwater.

[0084] <<Coloring test using test pattern A>> Tests were conducted using the compression-molded bath additives of Examples 1-19 and Comparative Examples 1-7. 1. As shown in Figures 1(a) and 1(b), the color of the surface at the bottom of the bathtub 3 where the compression-molded bath additive is to be placed was measured in advance using a spectrophotometer (Konica Minolta "CM-26d") at a position corresponding to the center of the compression-molded bath additive 1 (center measurement point C1) and two points 3 cm horizontally away from that point on the surface of the bathtub bottom (outer measurement points C2, C3), using the SCE (Specular Reflectance Rejection) method, and the average value of the three points was calculated. 2. The compression-molded bath additive 1 was placed directly on the bottom of the bathtub 3 so that its center approximately overlapped with the central measurement point C1. The compression-molded bath additive 1 was then secured with a cylinder 2 (a cylinder with an inner diameter of 87.1 mm and a height of 28.9 mm, with openings on both the top and bottom) to prevent it from moving. Then, 40°C water was poured into the bathtub 3 at a flow rate of 0.25 L / s to fill it to 20 L and dissolve the compression-molded bath additive 1. 3. After the compression-molded bath additive 1 was completely dissolved, the plug in the bathtub 3 was removed and all the bathwater was drained. 4. The area where the compression-molded bath additive 1 was placed was rinsed with 40°C water, and then scrubbed 10 times back and forth with a dry Kimtowel. After that, the color of the bathtub surface at three designated points (center measurement point C1, outer measurement points C2, C3) was measured using a spectrophotometer, and the average value of the three points was calculated. 5. Color before the start of the test (L * 1, a * 1, b *1) and the color after the test (L * 2, a * 2, b * 2) From the following equation (1), ΔE * The ab ratio was calculated, and the degree of coloration was evaluated. ΔE * ab=[(ΔL * ) 2 +(Δa * ) 2 +(Δb * ) 2 ] 1 / 2 ...(1) ΔL * =L * 1-L * 2 Δa * =a * 1-a * 2 Δb * =b * 1-b * 2 6. Furthermore, the color suppression rate (%) for the compression-molded bath additives of Examples 1 to 19 was calculated using the following formula (2). Color suppression rate (%) = 100 - {(measured ΔE * ab)÷(ΔE of the comparison example) * ab) × 100} ... (2)

[0085] The above color suppression rates were calculated using Comparative Example 1 as a control for Examples 1 to 13, and similarly for subsequent examples, Comparative Example 2 was used for Example 14, Comparative Example 3 for Example 15, Comparative Example 4 for Example 16, Comparative Example 5 for Example 17, Comparative Example 6 for Example 18, and Comparative Example 7 for Example 19, all as control references.

[0086] The results of the coloring test using test pattern A are shown in Tables 4 and 5, and in Figures 2 and 3.

[0087] [Table 4]

[0088] [Table 5]

[0089] <<Coloring test using test pattern B>> Tests were conducted using the compression-molded bath additives of Examples 6, 8, and 9 and Comparative Example 1. 1. Fill the bathtub with 200 liters of 40°C water, add the compressed bath additive, and drain the water after confirming that it has completely dissolved. 2. The entire bathtub was rinsed with 40°C water, and the stained areas were then scrubbed 10 times back and forth with a dry Kimtowel. The degree of staining was then visually inspected. The degree of staining was evaluated according to the following evaluation criteria. [Evaluation Criteria] ○: It is lightly colored, but there are no dark areas. ×: There are variations in shade, and the darker areas are unacceptably discolored.

[0090] Upon visual inspection, comparative example 1 showed discoloration in the area where the compression-molded bath additive was in contact with the bathtub surface, with variations in shade and some areas being darker (Evaluation: ×). In contrast, in Examples 6, 8, and 9, discoloration was observed in the areas where the compression-molded bath additive was in contact with the bathtub surface. However, compared to Comparative Example 1, the discoloration was lighter and more uniform overall, with no darker areas (Evaluation: ○).

[0091] <Evaluation Test 2: Dissolution Time Measurement> Dissolution time was measured using two test patterns: Test Pattern A, in which the compression-molded bath additive was placed in the bathtub before adding the bathwater, and Test Pattern B, in which the compression-molded bath additive was added to the bathwater.

[0092] <<Measuring dissolution time using test pattern A>> Tests were conducted using the compression-molded bath additives of Examples 1-19 and Comparative Examples 1-7. A compression-molded bath additive was placed at the bottom of the bathtub and secured with a cylinder (with an inner diameter of 87.1 mm and a height of 28.9 mm, with openings on both the top and bottom) to prevent it from moving. Then, 20 liters of 40°C water were poured into the bathtub at a flow rate of 0.25 L / s. The time from the start of the water inflow until the compression-molded bath additive had completely dissolved was measured and defined as the dissolution time.

[0093] <<Measuring dissolution time in test pattern B>> Tests were conducted using the compression-molded bath additives of Examples 1-9 and Comparative Example 1. A 15L plastic bucket was filled with 10L of 40°C water, and a compression-molded bath additive was added. The time from the start of dissolution to the completion of dissolution was measured and defined as the dissolution time.

[0094] The results of dissolution time measurements using test pattern A and test pattern B are shown in Tables 6 and 7.

[0095] <Evaluation Test 3: pH Measurement> Tests were conducted using the compression-molded bath additives of Examples 1-19 and Comparative Examples 1-7. pH measurements were performed under conditions simulating actual bathing. 1. Fill the bathtub with 200 liters of 40°C water, add the compressed bath additive, and allow it to dissolve completely. 2. Approximately 50 mL of the bathwater from step 1 was measured, and its pH was measured using a benchtop pH meter "LAQUA F-71" (manufactured by HORIBA).

[0096] The pH measurement results of the bathwater are shown in Tables 6 and 7.

[0097] [Table 6]

[0098] [Table 7]

[0099] Evaluation Test 1 showed that in both cases—when the compressed bath additive was placed in the bathtub before adding bathwater, and when the compressed bath additive was added to the bathwater—Examples 1-19 showed a 22% or greater reduction in discoloration compared to comparative examples containing the same type and amount of pigment. This indicates that nonionic surfactants have the effect of suppressing pigment discoloration to the bottom of the bathtub. Furthermore, Evaluation Test 2 showed that all of the compression-molded bath additives in Examples 1 to 19 took more than 5 minutes to dissolve completely, indicating a long dissolution time. Additionally, Evaluation Test 3 showed that the compression-molded bath additives in the examples made the bathwater alkaline during actual use. These findings demonstrate that the compression-molded bath additives of the present invention can foam for a long time and provide a pleasant bathing experience. Based on the above, the compression-molded bath additive of the present invention improved the feel of the bathwater, extended the dissolution time, and suppressed discoloration of the bathtub when added to the bathwater. [Explanation of Symbols]

[0100] 1. Compression-molded bath additive 2 tubes 3 Bathtub C1 Center measurement point C2,C3 Outside measurement point

Claims

1. The following components (A) to (D): (A) Carbonate (B) Organic acid (C) Pigment (D) Nonionic surfactants It contains, A compression-molded bath additive having a carbonate content of 70% by mass or more.

2. A compression-molded bath additive according to claim 1, having a weight of 80g or more.

3. A compression-molded bath additive according to claim 1 or 2, which is effervescent.

4. A method for preventing the adhesion of the (C) pigment to a bathtub by including (D) a nonionic surfactant in a compression-molded bath additive containing (A) a carbonate, (B) an organic acid, and (C) a pigment, wherein the content of (A) the carbonate is 70% by mass or more.

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