Cooling agent composition

Abstract

To provide cooling agent compositions that use no ethanol as the main component of a solvent and continue to exert the cooling effect of a cooling component for a time equal to or longer than that of a conventional one.SOLUTION: A cooling agent composition of the present invention has an aqueous solution in which a cooling component micellized by a nonionic surfactant is dispersed. Further, the cooling component is contained in an amount of 0.01 to 6.00 mass% and the nonionic surfactant is contained in an amount of 0.10 to 10.00 mass% with respect to the total amount of the cooling agent composition. Further, the nonionic surfactant is a mixture of a lipophilic surfactant and a hydrophilic surfactant.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a cooling sensation composition that can exert a cooling sensation effect without using ethanol as a main component. [Background technology]

[0002] As a measure against the summer heat, various types of cooling sensation compositions or cooling sensation cosmetics have been developed that are sprayed directly onto the skin or onto the surface of clothing that comes into contact with the skin to provide a refreshing sensation (see, for example, Patent Documents 1 to 4). L-menthol is generally used as the main ingredient of these cooling sensation compositions. The cooling sensation effect of L-menthol does not actually lower the temperature, but rather gives a sensory cooling sensation by acting directly on the nerves.

[0003] L-menthol is easily soluble in organic solvents and concentrated hydrochloric acid, but is extremely insoluble in water. Therefore, in conventional cooling sensation compositions, L-menthol is used in the form of a solution in ethanol. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2000-239142 A [Patent Document 2] JP 2002-80335 A [Patent Document 3] JP 2004-269368 A [Patent Document 4] JP 2010-84269 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, since the above cooling sensation composition is composed of L-menthol dissolved in ethanol, it may cause unpleasant irritation to users with sensitive skin, or may ignite when used in closed rooms or spaces with insufficient ventilation. Therefore, attempts have been made to replace the main component ethanol with water and simply dissolve L-menthol in water, but this has the problem that the L-menthol component itself is not water-soluble and cannot be easily dissolved.

[0006] Therefore, the present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a cooling sensation composition that does not contain ethanol as a main solvent and that continues to exert the cooling effect of the cooling sensation component for a period of time equal to or longer than that of conventional compositions. [Means for solving the problem]

[0007] Therefore, the cooling sensation agent composition of the present invention is characterized in that a cooling sensation component micelle-formed by a nonionic surfactant is dispersed in an aqueous solution. In addition, the cooling sensation agent composition of the present invention preferably contains the cooling sensation component in an amount of 0.01 to 6.00% by mass and the nonionic surfactant in an amount of 0.10 to 10.00% by mass based on the total amount of the cooling sensation agent composition.

[0008] According to the present invention having such characteristics, in the cooling sensation agent composition which is an aqueous solution using water instead of ethanol as a solvent, the cooling sensation component can be well dispersed and a refreshing sensation can be imparted for a long period of time when sprayed.

[0009] In the cooling sensation agent composition of the present invention, the nonionic surfactant is preferably a mixture of a lipophilic surfactant and a hydrophilic surfactant. According to such an embodiment, the cooling sensation component can be well micelle-formed, and a stable cooling sensation agent can be obtained.

[0010] In the cooling sensation agent composition of the present invention, the cooling sensation component micellized by the nonionic surfactant preferably has a particle size of 5 to 200 nm.In addition, in the cooling sensation agent composition of the present invention, it is preferable that a stabilizer is further contained in an amount of 0.01 to 10.00 mass %.

[0011] In the cooling sensation agent composition of the present invention, the cooling sensation component is preferably L-menthol, isopulegol, camphor, cineol, menthone, menthyl lactate, or menthyl succinate. Effect of the Invention

[0012] According to the cooling sensation agent composition of the present invention, it is possible to provide a cooling sensation agent composition which does not use ethanol as a main solvent and which continuously exerts the cooling effect of the cooling sensation ingredient for a period of time equal to or longer than that of conventional compositions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In order to solve the above problems, the present inventors have conducted extensive research into the dissolution of cooling sensation ingredients in cooling sensation compositions, and as a result have found that by forming the cooling sensation ingredient into micelles, it is possible to satisfactorily disperse the cooling sensation ingredient in an aqueous solution even when the solvent is water, thereby leading to the invention of the cooling sensation composition of the present invention.

[0014] Hereinafter, the cooling sensation agent composition according to the embodiment of the present invention will be described in detail. However, the present invention is not limited to the following embodiment.

[0015] The greatest feature of the cooling sensation composition of the present invention is that the cooling sensation component is dispersed in an aqueous solution in the form of micelles formed by a nonionic surfactant. According to this configuration, in the aqueous solution cooling sensation composition in which water is used as a solvent instead of ethanol, the cooling sensation component is well dispersed without precipitating as needle-like crystals even at low temperatures, and when sprayed, it can provide a refreshing sensation for a long time. In addition, since the cooling sensation component is hardly viscous, it can be well sprayed by a spray.

[0016] In the cooling sensation agent composition of the present invention, the particle size of the cooling sensation component micellized by the nonionic surfactant is preferably 5 to 200 nm. In order to make the size of the micelles smaller than 5 nm, it is necessary to physically reduce the size using a device called a fluitizer, which is not preferable. On the other hand, if the size of the micelles exceeds 200 nm, it is not preferable because it becomes very difficult to form the micelles.

[0017] The cooling sensation agent composition of the present invention preferably contains 0.01 to 6.00% by mass of a cooling sensation ingredient, 0.10 to 10.00% by mass of a nonionic surfactant, and 0.01 to 10.00% by mass of a stabilizer, based on the total amount of the cooling sensation agent composition. Also, in the micelles in the cooling sensation agent composition of the present invention, the cooling sensation ingredient is preferably blended in the range of 8.33 to 23.08% by mass, the nonionic surfactant is preferably blended in the range of 38.46 to 83.33% by mass, and the stabilizer is preferably blended in the range of 8.33 to 38.46% by mass.

[0018] The cooling sensation component in the present invention may be any component that is normally used in cosmetics, etc., and may be blended in the range of 0.01 to 6.00% by mass relative to 100% by mass of the cooling sensation agent composition of the present invention. If the blending amount of the cooling sensation component is less than 0.01% by mass, a sufficient cooling sensation cannot be obtained, while if the blending amount is more than 6.00% by mass, it is not practical from the standpoint of economics. In addition, the cooling sensation component may be blended in the micelles of the cooling sensation agent composition in the range of 8.33 to 23.08% by mass. If the blending amount of the cooling sensation component in the micelles is less than 8.33% by mass, a sufficient cooling sensation cannot be obtained, while if the blending amount in the micelles is more than 23.08% by mass, it is not practical from the standpoint of economics.

[0019] The cooling sensation component in the present invention may be any of menthol analogs or menthol derivatives such as L-menthol, isopulegol, camphor, cineol, menthone, menthyl lactate, menthyl succinate, etc. Among these cooling sensation components, L-menthol is most preferred in the present invention from the viewpoints of maintaining the cooling sensation effect and economical aspects.

[0020] The nonionic surfactant in the present invention is a component that is blended to make the cooling sensation component micellize, and enables the cooling sensation component to be dispersed in an aqueous solution while suppressing the volatilization of the cooling sensation component. The form of this nonionic surfactant is not particularly limited, but a liquid or paste form is preferred. In addition, the nonionic surfactant in the present invention is preferably a well-balanced blend of two types of surfactants, a lipophilic surfactant and a hydrophilic surfactant.

[0021] The amount of the nonionic surfactant in the present invention is preferably in the range of 0.10 to 10.00% by mass, and more preferably in the range of 2.00 to 6.00% by mass. If the amount of the nonionic surfactant is less than 0.10% by mass, the cooling sensation component cannot be sufficiently micellized. On the other hand, even if the amount is more than 10.00% by mass, the micellization does not proceed any further, and it is desirable to keep it within 10.00% by mass from an economical point of view. In addition, the nonionic surfactant can be blended in the micelles of the cooling sensation agent composition in the range of 38.46 to 83.33% by mass. If the amount of the nonionic surfactant in the micelles is less than 38.46% by mass, the cooling sensation component cannot be sufficiently micellized. On the other hand, even if the amount in the micelles exceeds 83.33% by mass, the micellization does not proceed any further, and it is desirable to keep it within this range from an economical point of view.

[0022] The lipophilic surfactant in the present invention means a surfactant having an HLB value of less than 7. Specifically, alkyl glyceryl ethers, glycerin fatty acid esters, sorbitan fatty acid esters, propylene glycol fatty acid esters, glycerin fatty acid esters, polyglycerin fatty acid esters, and salts thereof can be used.

[0023] The hydrophilic surfactant in the present invention means a surfactant having an HLB value of higher than 7. Specific examples of the hydrophilic surfactant that can be used include glycerin fatty acid esters, sorbitan fatty acid esters, polyethylene glycol fatty acid esters, polyoxyalkylene alkyl ethers, polyoxyalkylene fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene glycerin fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters (polyoxysorbitol fatty acid esters), polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene polyoxypropylene glycol, polyoxyethylene hydrogenated castor oil, polyoxyethylene higher alcohol esters, polyglycerin fatty acid esters, and salts thereof.

[0024] Furthermore, the stabilizer to be blended in the cooling sensation agent composition of the present invention may be blended in an amount sufficient to compensate for the lack of stable micelles due to recrystallization of the cooling sensation agent by the cooling sensation agent and nonionic surfactant alone, and may be blended in the range of 0.01 to 10.00% by mass. If the blending amount of the stabilizer is less than 0.01% by mass, the cooling sensation agent cannot be stably turned into micelles. On the other hand, the blending amount of the stabilizer may be blended in more than 10.00% by mass, but since the blending amount of the nonionic surfactant must be increased accordingly and the stability of the cooling sensation agent composition of the present invention may be lost if the stabilizer is added in excess, it is desirable to keep the blending amount within 10.00% by mass. Furthermore, the stabilizer may be blended in the micelles of the cooling sensation agent composition in the range of 8.33 to 38.46% by mass. If the blending amount of the stabilizer in the micelles is less than 8.33% by mass, the cooling sensation agent cannot be stably turned into micelles. On the other hand, if the blending amount in the micelle exceeds 38.46% by mass, the stability of the cooling sensation agent composition of the present invention may be lost, which is undesirable.

[0025] The form of the stabilizer in the present invention is not particularly limited, but is preferably a liquid or paste. The stabilizer may be one used in cosmetics, etc., and is not particularly limited, but examples thereof include oils and fats, fatty acids, esters, higher alcohols, hydrocarbons, silicone oils, etc.

[0026] Examples of the oils and fats that can be used in the present invention include almond oil, avocado oil, linseed oil, olive oil, apricot kernel oil, sesame oil, camellia oil, safflower oil, cinnamon oil, camellia oil, corn oil, rapeseed oil, castor oil, sunflower oil, grape oil, jojoba oil, macadamia nut oil, evening primrose oil, wheat germ oil, soybean oil, tea seed oil, rice bran oil, rice germ oil, cottonseed oil, and peanut oil.

[0027] Examples of fatty acids that can be used in the present invention include heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, pentadecanoic acid, heptadecanoic acid, nonadecanoic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, and arachidonic acid.

[0028] Examples of the esters used in the present invention include isopropyl isostearate, cholesterol isostearate, isotridecyl isononanoate, isononyl isononanoate, octyl isopalmitate, cetyl ethylhexanoate, polyglyceryl octacaprylate, cetyl octanoate, isodecyl oleate, decyl oleate, neopentyl glycol diethylhexanoate, butyl stearate, pentaerythrityl tetraethylhexanoate, pentaerythrityl tetraoctanoate, tri(caprylic acid / capric acid)glyceryl, triisostearin, trimethylolpropane triisostearate, triethylhexanoin, isopropyl palmitate, ethylhexyl palmitate, octyl palmitate, polyethylene glycol, isopropyl myristate, isopropyl myristate, octyldodecyl myristate, myristyl myristate, hexyl laurate, cetyl lactate, and myristyl lactate.

[0029] Examples of the higher alcohol used in the present invention include isostearyl alcohol, octyl alcohol, octyldodecanol, and oleyl alcohol.

[0030] Examples of the hydrocarbon oil that can be used in the present invention include octane, decane, dodecane, isododecane, hexadecane, isohexadecane, paraffin, isoparaffin, liquid paraffin, squalane, squalene, and olefin oligomers.

[0031] Examples of silicone oils that can be used in the present invention include linear silicones such as dimethylpolysiloxane and methylphenylpolysiloxane, and cyclic silicones such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane.

[0032] Although essential oils are also oils and fats used in cosmetics and the like, they are not used as stabilizers in the cooling sensation composition of the present invention for reasons such as the risk that the fragrance of the blended essential oil may mix with the refreshing fragrance specific to the cooling sensation ingredient and become an unpleasant fragrance, and the unit price of essential oils is very high and therefore not economical.

[0033] The preservatives that can be added to the cooling sensation agent composition of the present invention can be any preservative that can be dissolved in the cooling sensation agent composition of the present invention, regardless of whether it is lipophilic or hydrophilic.Specific examples of the preservatives include sodium benzoate, isopropylmethylphenol, methylparaben, ethylparaben, benzalkonium chloride, octanediol, glyceryl caprylate, glycerin fatty acid ester, chlorphenesin, salicylic acid, potassium sorbate, sodium dehydroacetate, ethyl parahydroxybenzoate, butyl parahydroxybenzoate, propyl parahydroxybenzoate, methyl parahydroxybenzoate, methyl parahydroxybenzoate, phenoxyethanol, hexanediol, benzalkonium chloride, pentanediol, methylisothiazolinone, and methylchloroisothiazolinone.

[0034] The preservative in the present invention can be blended in an amount that generally provides a preservative effect, regardless of whether it is lipophilic or hydrophilic. Specifically, when the preservative is a paraoxybenzoic acid ester or a sodium salt thereof, it can be blended in an amount of up to 1.00% by mass relative to 100% by mass of the cooling sensation agent composition of the present invention. When the preservative is a pentanediol, it can be blended in an amount of 3.00 to 5.00% by mass relative to 100% by mass of the cooling sensation agent composition of the present invention. Furthermore, when the preservative is a hexanediol, it can be blended in an amount of 1.50 to 2.00% by mass relative to 100% by mass of the cooling sensation agent composition of the present invention.

[0035] In addition, the cooling agent of the present invention may contain solvents such as isopropylene glycol, glycerin, propylene glycol, butylene glycol, additives such as animal and plant extracts (animal and plant extracts), and fragrances within a range that does not impair the effects of the present invention. EXAMPLES

[0036] Next, the present invention will be described in more detail based on examples and comparative examples, but the present invention is not limited to these examples.

[0037] 1. Comparison of the present invention with conventional products <Example 1> First, methylparaben and phenoxyethanol, which are preservatives, were dissolved in purified water to a final concentration of 0.30% by mass and 1.00% by mass. In addition, L-menthol, which is a cooling sensation component, sorbitan fatty acid ester (trade name: Rheodol TW-0120V, manufactured by Kao Corporation), which is a hydrophilic surfactant, glyceryl oleate (trade name: Rheodol MO-60, manufactured by Kao Corporation), which is a lipophilic surfactant, and octyldodecanol (trade name: Kalcol 200GD, manufactured by Kao Corporation), which is a higher alcohol (stabilizer), were uniformly mixed and dissolved to a final concentration of 3.00% by mass, 2.00% by mass, 2.00% by mass, and 3.00% by mass, respectively. Here, if the above mixture is not uniformly dissolved, it may be heated to 50°C. Next, the above mixture was mixed with the above purified water to prepare a cooling sensation agent composition of Example 1 of the present invention in which L-menthol was micelle-formed by the surfactant. The prepared cooling sensation agent composition had a whitish blue color.

[0038] <Comparative Example 1> L-menthol, a cooling sensation component, was dissolved in ethanol to a concentration of 3.00% by mass to prepare a cooling sensation composition of Comparative Example 1, which corresponds to a conventional product in which ethanol is the main solvent.

[0039] evaluation The cooling sensation agent compositions of Example 1 and Comparative Example 1 obtained as described above were sprayed onto a 40 mm x 40 mm cotton / polyester (50 / 50) cloth bag, and the amount of coating was measured. Next, the cloth bag onto which the cooling sensation agent composition was applied was left at 50°C, 40°C, and 30°C for 3 minutes, and the remaining amount of the cooling sensation agent composition was measured. The cooling sensation agent compositions of Example 1 and Comparative Example 1 were measured four times, and the results are shown in Tables 1 to 6, respectively.

[0040] [Table 1]

[0041] [Table 2]

[0042] [Table 3]

[0043] [Table 4]

[0044] [Table 5]

[0045] [Table 6]

[0046] As is clear from Tables 1 to 6, the cooling sensation agent composition of Example 1 of the present invention has a volatility rate of 20.40% (50°C), 20.02% (40°C), and 11.12% (30°C), respectively, which indicates that the volatility is significantly suppressed compared to the volatility rates of the cooling sensation agent composition of Comparative Example 1, which are 54.49% (50°C), 47.35% (40°C), and 40.62% (30°C). This result is due to the large difference in vapor pressure between the solvents water and ethanol, and indicates that the cooling sensation agent composition of Example 1, which uses water as the solvent, has a suppressed amount of evaporation from the cloth bag and can continue to impart a cooling sensation for a longer period of time. Note that the vapor pressure here indicates the force of changing from a liquid (solid) to a gaseous state, and the higher the value, the easier it is to evaporate.

[0047] 2. State stability of L-menthol and stabilizers Next, the amount of stabilizer blended relative to L-menthol in the cooling sensation agent composition of the present invention was varied to verify the suitable amount of stabilizer blended. Each cooling sensation agent composition was prepared by varying the blending amount of L-menthol in the range of 1.00 to 3.00 mass% and the blending amount of stabilizer in the range of 0.00 to 5.00 mass% in increments of 1.00 mass% in the composition of Example 1 above.

[0048] Each prepared cooling sensate composition was left to stand for one week in a thermostatic chamber at 20°C, which is assumed to be room temperature, and the state stability of the cooling sensate composition was visually evaluated according to the following criteria. The state stability was evaluated as follows: ◯ indicates that the entire cooling sensate composition was whitish blue or opaque, no separation was observed, and micellization was observed; × indicates that the cooling sensate composition was separated. The results of the blending amount of stabilizer in each cooling sensate composition are shown in Table 7.

[0049] [Table 7]

[0050] As is clear from Table 7, it was confirmed that when a stabilizer is not added, the cooling sensation agent composition separates and cannot be made into a micelle. Also, if the amount of L-menthol added is small, the amount of stabilizer added can be increased to compensate for this, thereby obtaining a cooling sensation agent composition of the present invention in which L-menthol is made into a micelle. This shows that a good cooling sensation agent composition of the present invention can be prepared by adding a stabilizer appropriately.

[0051] 3. Verification of L-menthol precipitation at low temperatures L-menthol precipitates as needle-like crystals at low temperatures, which is problematic in that good stability of appearance cannot be maintained. Furthermore, when it precipitates as crystals, the L-menthol concentration in the cooling sensation agent composition decreases, which causes a problem of reduced refreshing sensation. Therefore, the precipitation of needle-like crystals at low temperatures was examined. Note that the cooling sensation agent compositions used in this examination were the same as those used in the above examination.

[0052] Each cooling sensation composition thus prepared was left to stand for 2 weeks at 5 to 10°C, and the presence or absence of precipitation of needle-like crystals was judged visually and by optical microscope according to the following criteria. The evaluation criteria for the presence or absence of precipitation were as follows: ◯: no difference from the initial product and no precipitation of needle-like crystals was observed; △: a trace of crystal precipitation was observed; and ×: needle-like crystals were precipitated and the cooling sensation composition was separated or solidified. The results of the appearance of each cooling sensation composition at low temperatures are shown in Table 8.

[0053] [Table 8]

[0054] As shown in Table 8, it was confirmed that needle-like crystals of L-menthol precipitate at low temperatures even when an excessive amount of stabilizer is blended. This shows that it is possible to obtain a cooling sensation agent composition of the present invention in which L-menthol does not precipitate even at low temperatures by blending an appropriate amount of stabilizer.

Claims

1. In the aqueous solution, A nonionic surfactant; a cooling sensation component that is micellized by the nonionic surfactant and dispersed in the aqueous solution; a stabilizer for stabilizing the micellar state of the cooling sensation component; A cooling sensation composition comprising: the non-ionic surfactant is a mixture of a lipophilic surfactant and a hydrophilic surfactant, the cooling sensation component is L-menthol, isopulegol, camphor, cineol, menthone, menthyl lactate, or menthyl succinate; 1. A cooling sensation agent composition for spray application to skin or clothing that comes into contact with the skin, characterized in that the content of the cooling sensation ingredient is 1.00 to 3.00 mass%, the content of the nonionic surfactant is 0.10 to 10.00 mass%, and the content of the stabilizer is 2.00 to 5.00 mass%, relative to the total amount of the cooling sensation agent composition (however, when the content of the cooling sensation ingredient is 1.00 mass% or more and less than 2.00 mass%, the content of the stabilizer is excluding the range of 2.00 mass% or more and less than 3.00 mass%, when the content of the cooling sensation ingredient is 2.00 mass% or more and less than 3.00 mass%, the content of the stabilizer is excluding the range of more than 4.00 mass% and 5.00 mass% or less, and when the content of the cooling sensation ingredient is 3.00 mass%, the content of the stabilizer is excluding the range of more than 3.00 mass% and 5.00 mass% or less).

2. The cooling sensation composition for spray application to skin or clothing that comes into contact with the skin according to claim 1, characterized in that the cooling sensation component micellized by the nonionic surfactant has a particle diameter of 5 to 200 nm.

3. 3. A cooling sensation agent composition for spray application to the skin or clothing that comes into contact with the skin, as described in claim 1 or 2, characterized in that the stabilizer is an oil, a fatty acid, an ester, a higher alcohol, a hydrocarbon, or a silicone oil.

4. The cooling sensation agent composition for spray application to the skin or clothing that comes into contact with the skin according to any one of claims 1 to 3, characterized in that the cooling sensation agent composition does not contain ethanol.

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