Cosmetic sponge

Abstract

To provide a cosmetic sponge exhibiting superior retention of a cooling sensation.SOLUTION: A cosmetic sponge is composed of a urethane resin composition prepared through mixing of a polyol composition containing a polyol and a sugar alcohol with a polyisocyanate.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a cosmetic sponge.

Background Art

[0002] To apply base makeup cosmetics such as foundation to the skin, a sponge formed in a flat shape or the like having a certain thickness is used. When applying cosmetics using this sponge, in areas with a large surface area such as the cheeks and forehead, it can be applied as it is using a large part of the sponge surface. However, in fine areas such as around the eyes and the bridge of the nose, the sponge is bent and wound around the finger for application work. Therefore, high flexibility and elasticity are required for cosmetic sponges. In addition, as the cosmetic sponge is continuously used, cosmetics and sebum adhere to the surface, and the ability to pick up cosmetics and the adhesion to the skin decrease. Therefore, it is necessary to wash and dry it regularly, and durability that can withstand repeated use is also required.

[0003] In addition, since a cosmetic sponge comes into direct contact with the skin, it is also necessary for it to be soft and have an excellent texture. Furthermore, if it can impart a refreshing feeling or the like when applied, it can be an even more excellent product in terms of usability.

[0004] Regarding the technology that gives a cooling sensation when in contact with the skin, research has been carried out on textile products. For example, in Patent Document 1, a contact-cooling fabric that can impart a cooling sensation when touching the skin is disclosed by spraying or dipping a contact-cooling agent such as sugar alcohol on a fabric formed of water-absorbing fibers.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] However, when this technology is applied to a cosmetic sponge, there is a problem that the contact cooling agent runs off during repeated washing with water or the like, and the contact cooling effect does not last.

Summary of the Invention

Problems to be Solved by the Invention

[0007] An object of the present invention is to provide a cosmetic sponge that can give a cooling feeling during application while maintaining elasticity, flexibility, etc. suitable for a cosmetic sponge, and that is also excellent in the persistence of its effect.

Means for Solving the Problems

[0008] As a result of intensive studies to solve the above problems, the present inventors have found that by forming a polyurethane foam using a urethane resin composition obtained by mixing a polyol composition containing a polyol and a sugar alcohol with a polyisocyanate, a cosmetic sponge can be obtained that can impart a cooling feeling over a long period without impairing flexibility and touch, and have thus completed the present invention.

[0009] The means for solving the above problems include the following aspects. <1> A cosmetic sponge formed from a urethane resin composition obtained by mixing a polyol composition containing a polyol and a sugar alcohol with a polyisocyanate. <2> The cosmetic sponge according to <1>, wherein the sugar alcohol is one or more selected from the group consisting of sorbitol, mannitol, xylitol, and erythritol. <3> The cosmetic sponge according to <1> or <2>, wherein the polyol composition contains 0.1 to 10 parts by mass of the sugar alcohol per 100 parts by mass of the polyol. <4> The cosmetic sponge according to any one of <1> to <3>, wherein the polyol composition further contains a foaming agent. <5> The cosmetic sponge according to any one of <1> to <4>, wherein the polyol composition further contains a catalyst.

Effects of the Invention

[0010] The cosmetic sponge of the present invention gives a refreshing feeling during use and has excellent persistence.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the content of the present invention will be described in detail. The description of the present invention described below may be based on a preferred embodiment of the present invention, but the present invention is not limited to such an embodiment. In this specification, "~" indicating a numerical range is used to mean including the numerical values described before and after it as the lower limit value and the upper limit value.

[0012] <Polyisocyanate> The urethane resin composition used in the present invention contains a polyisocyanate. In this specification, "polyisocyanate" means a compound having two or more isocyanate groups in one molecule. Examples of polyisocyanates include aromatic polyisocyanates, alicyclic polyisocyanates, aliphatic polyisocyanates, and the like. The above polyisocyanates may be used alone or in combination of two or more.

[0013] Examples of aromatic polyisocyanates include phenylenediisocyanate, 2,4- or 2,6-toluenediisocyanate, diphenylmethane diisocyanate (hereinafter also referred to as "MDI"), dimethyldiphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, polymethylene polyphenyl polyisocyanate (hereinafter also referred to as "polymeric MDI"), and the like. Among them, from the viewpoints of the cooling effect, flexibility, touch, etc., it is preferable to use 2,4- or 2,6-toluenediisocyanate, MDI, or polymeric MDI, and polymeric MDI is more preferable.

[0014] Examples of the alicyclic polyisocyanate include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, dimethyldicyclohexylmethane diisocyanate, and the like. Among them, from the viewpoints of the cooling sensation imparting effect, flexibility, and touch, it is preferable to use cyclohexylene diisocyanate or isophorone diisocyanate.

[0015] Examples of the aliphatic polyisocyanate include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, and the like. Among them, from the viewpoints of the cooling sensation imparting effect, flexibility, and touch, it is preferable to use hexamethylene diisocyanate.

[0016] The isocyanate groups of the polyisocyanate relative to 1 equivalent of the active hydroxyl groups in the polyol composition described below are preferably 0.7 to 5 equivalents, more preferably 0.8 to 1.5 equivalents, and even more preferably 0.95 to 1.2 equivalents. When the blowing agent described below contains water, the isocyanate groups of the polyisocyanate are preferably 0.7 to 5 equivalents, more preferably 0.8 to 1.5 equivalents, relative to 1 equivalent of the active hydrogen groups of water.

[0017] [Polyol Composition] <Sugar Alcohol> The polyol composition used in the present invention contains a sugar alcohol. In the present specification, "sugar alcohol" is a sugar produced by reducing the carbonyl group of a sugar having a carbonyl group to a hydroxyl group.

[0018] Examples of the sugar alcohol include sorbitol, mannitol, xylitol, erythritol, and the like. Among them, from the viewpoints of the cooling sensation imparting effect, flexibility, and touch, xylitol is preferable. The above sugar alcohols may be used alone or in combination of two or more.

[0019] The content of the sugar alcohol in the polyol composition is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, and still more preferably 1 to 3 parts by mass, from the viewpoints of the cooling sensation imparting effect, flexibility, and touch, etc., based on 100 parts by mass of the polyol described later.

[0020] <Polyol> The polyol composition used in the present invention contains a polyol. The polyol is not particularly limited, and examples thereof include polycarbonate polyol, polyether polyol, polyester polyol, etc. Among them, from the viewpoints of the cooling sensation imparting effect, flexibility, and touch, etc., polycarbonate polyol is preferred. The above polyol may be used alone or in combination of two or more.

[0021] (Polycarbonate polyol) Examples of the polycarbonate polyol include polycarbonate diol having two hydroxyl groups in one molecule of polycarbonate polyol, polycarbonate triol having three hydroxyl groups in one molecule, polycarbonate tetraol having four hydroxyl groups in one molecule, etc. The above polycarbonate polyol may be used alone or in combination of two or more.

[0022] The polycarbonate polyol can be synthesized, for example, by subjecting a carbonic acid ester and a diol to a transesterification reaction under a catalyst.

[0023] The carbonic acid ester is not particularly limited, and examples thereof include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, etc. The above carbonic acid ester may be used alone or in combination of two or more.

[0024] Examples of the diol include aliphatic diol and alicyclic diol. Although the aliphatic diols and alicyclic diols are not particularly limited, linear or branched aliphatic diols or alicyclic diols having 3 to 13 carbon atoms are preferred, linear or branched aliphatic diols having 4 to 11 carbon atoms are more preferred, and branched aliphatic diols having 4 to 11 carbon atoms are even more preferred. By having branches, it is possible to suppress the viscosity of the resulting polycarbonate polyol from becoming too high.

[0025] Specific examples of the above aliphatic diols and alicyclic diols include 3-methyl-1,5-pentanediol (hereinafter also referred to as "MPD"), 1,6-hexanediol (hereinafter also referred to as "HD"), 2-methyl-1,8-octanediol (hereinafter also referred to as "MOD"), 1,9-nonanediol (hereinafter also referred to as "ND"), 1,4-butanediol, cyclohexanedimethanol, and the like. The above aliphatic diols and alicyclic diols may be used alone or in combination of two or more. Among them, from the viewpoint of obtaining a liquid polycarbonate polyol, the combined use of ND and MOD, and the combined use of HD and MPD are preferred.

[0026] When ND and MOD are used in combination, the weight ratio of ND to MOD (ND:MOD) is preferably 80:20 to 5:95, and more preferably 65:35 to 10:90. By being within the above range, a liquid polycarbonate polyol can be obtained.

[0027] When HD and MPD are used in combination, the weight ratio of HD to MPD (HD:MPD) is preferably 80:20 to 5:95, and more preferably 65:35 to 10:90. By being within the above range, a liquid polycarbonate polyol can be obtained.

[0028] In addition, polycarbonate polyol can be used to synthesize polycarbonate triol and polycarbonate tetrol by using triol and / or tetrol instead of the above diol or together with the diol.

[0029] The polycarbonate polyol preferably has a number average molecular weight in the range of 1,000 to 3,000. By being within this range, the flexibility of the formed polyurethane foam is improved. Also, a liquid polyol can be obtained. The number of hydroxyl groups of the polycarbonate polyol is preferably 2 or more on average per molecule, more preferably 2 to 4, and even more preferably 2 to 3.

[0030] Among them, it is preferable to use a polycarbonate diol and a polycarbonate triol in combination. By using them in combination, the heat resistance of the formed polyurethane foam can be improved.

[0031] When a polycarbonate diol and a polycarbonate triol are used in combination, the weight ratio of the polycarbonate diol to the polycarbonate triol is preferably 40:60 to 95:5, and more preferably 60:40 to 90:10. Such polycarbonate polyols are sold, for example, by Kuraray Co., Ltd. as Kuraray Polyol Polycarbonate Polyol.

[0032] (Polyether polyol) In the present invention, as the polyol, a polyether polyol can be used in combination with the polycarbonate polyol. By using the polycarbonate polyol and the polyether polyol in combination, it is possible to suppress the polyol viscosity from becoming too high. Also, the flexibility of the formed polyurethane foam is improved.

[0033] As the polyether polyol, those obtained by ring-opening polymerization of an alkylene oxide with an initiator having two or more hydroxyl groups can be used.

[0034] Examples of the initiator include diols such as bisphenol A, ethylene glycol, propylene glycol, butylene glycol, 1,6 - hexanediol, triols such as glycerin, trimethylolpropane, and amines such as ethylenediamine, butylenediamine, etc. The above initiator may be used alone or in combination of two or more.

[0035] Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, etc. The above alkylene oxide may be used alone or in combination of two or more.

[0036] Specific examples of the above polyether polyol include diglycerin, dipentaerythritol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polytetramethylene glycol, etc. Among them, from the viewpoint of the flexibility of the formed polyurethane foam, polyethylene glycol and polypropylene glycol are preferred. The number average molecular weight of the polyether polyol is preferably 500 - 5000.

[0037] The number of hydroxyl groups of the polyether polyol is on average 2 or more per molecule, preferably 2 or more and 4 or less, more preferably 2 or more and 3 or less.

[0038] The content of the polyether polyol is not particularly limited, but among 100 parts by mass of the polyol, 95 parts by mass or less is preferred, 80 parts by mass or less is more preferred, and 60 parts by mass or less is even more preferred. The lower limit value of the polyether polyol is not particularly limited, but 30 parts by mass or more is preferred.

[0039] <Blowing agent> The polyol composition used in the present invention preferably contains a blowing agent. Examples of the blowing agent include water, organic physical blowing agents, inorganic physical blowing agents, etc.

[0040] Examples of organic physical foaming agents include low-boiling hydrocarbons such as propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane; chlorinated aliphatic hydrocarbon compounds such as dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride; fluorine compounds such as CHF3, CH2F2, CH3F; hydrochlorofluorocarbon compounds such as trichloromonofluoromethane, trichlorotrifluoroethane, dichloromonofluoroethane (e.g., HCFC141B (1,1-dichloro-1-fluoroethane), HCFC22 (chlorodifluoromethane), HCFC142B (1-chloro-1,1-difluoroethane)); hydrofluorocarbons such as HFC-245FA (1,1,1,3,3-pentafluoropropane), HFC-365MFC (1,1,1,3,3-pentafluorobutane); hydrofluoroolefins such as HFO-1233ZD (E-1-chloro-3,3,3-trifluoropropene); ether compounds such as diisopropyl ether, etc. Examples of inorganic physical foaming agents include nitrogen gas, oxygen gas, argon gas, carbon dioxide gas, etc. Among them, from the viewpoint of obtaining a closed-cell foam, it is preferable to use water, hydrocarbons, or halogenated methane, and it is more preferable to use water. The above foaming agents may be used alone or in combination of two or more.

[0041] The content of the foaming agent is not particularly limited. For example, when water is used as the foaming agent, 0.5 to 10 parts by mass, preferably 1 to 5 parts by mass, is preferable with respect to 100 parts by mass of the polyol. When hydrocarbons or halogenated methane is used as the foaming agent, 5 to 75 parts by mass is preferable with respect to 100 parts by mass of the polyol.

[0042] <Catalyst> The polyol composition used in the present invention preferably contains a catalyst. By containing the catalyst, the reaction between the polyol and the polyisocyanate is promoted. Examples of the catalyst include organometallic catalysts, tertiary amine compounds, etc.

[0043] Examples of the organometallic catalyst include stannous diacetate, stannous dioctoate, stannous dioleate, stannous dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dioctyltin dilaurate, lead octoate, lead naphthenate, nickel naphthenate, cobalt naphthenate, and the like.

[0044] Examples of the tertiary amine compounds include N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylpropylenediamine, N,N,N',N",N"-pentamethyl-(3-aminopropyl)ethylenediamine, N,N,N',N",N"-pentamethyldipropylenetriamine, N,N,N',N'-tetramethylguanidine, 1,8-diazabicyclo[5.4.0]undecene-7, triethylenediamine, N,N,N',N'-tetramethylhexamethylenediamine, N-methyl-N'-(2-dimethylaminoethyl)piperazine, N,N'-dimethylpiperazine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, bis(2-dimethylaminoethyl)ether, and the like.

[0045] The content of the catalyst is not particularly limited. For example, when an organometallic catalyst is used as the catalyst, 0.001 to 0.5 parts by mass is preferable with respect to 100 parts by mass of the polyol. When a tertiary amine compound is used as the catalyst, 0.1 to 3 parts by mass is preferable with respect to 100 parts by mass of the polyol.

[0046] <Blowing agent> The polyol composition of the present invention preferably contains a blowing agent. By containing the blowing agent, the deviation in the size of the voids of the formed polyurethane foam can be suppressed. Examples of the foam stabilizer include known substances generally used in the production of polyurethane foams. For example, polydimethylsiloxane-polyalkylene oxide block polymers and vinylsilane-polyalkylene polyol polymers can be mentioned. The above foam stabilizer may be used alone or in combination of two or more.

[0047] <Other components> The polyol composition used in the present invention may further contain additives other than those described above. For example, antioxidants, chain extenders, surfactants, flame retardants, fillers, mold release agents, antioxidants, colorants, weathering agents, antibacterial agents, etc. can be mentioned.

[0048] The polyol composition obtained by mixing additives such as the above polyol, sugar alcohol, and foaming agent is preferably liquid at 30°C to 45°C, more preferably liquid at 25°C to 50°C, and still more preferably liquid at 20°C to 60°C. Since it is liquid at the foam formation temperature in this way, it is suitable for the foaming method. As for the viscosity of the polyol composition, when mixing with a stirrer having stirring blades described later at the molding temperature, it is preferably 10,000 mPa·s or less, and more preferably 7,000 mPa·s. When mixing using a high-pressure mixer described later, it can be used even if it is 10,000 mPa·s or more, preferably 20,000 mPa·s or less, and more preferably 15,000 mPa·s or less.

[0049] <Urethane resin composition> The urethane resin composition can be prepared by mixing a polyol composition prepared by previously kneading additives such as a polyol, a sugar alcohol, a foaming agent, and a catalyst with a polyisocyanate.

[0050] <Method for producing polyurethane foam> A polyurethane foam can be obtained by foaming and curing the above urethane resin composition. For example, a polyurethane foam can be produced by mixing and reacting a polyol composition containing additives such as a polyol, a sugar alcohol, a foaming agent, and a catalyst with a polyisocyanate, and simultaneously generating a gas to cause foaming. The mixing of the polyol composition and the polyisocyanate is preferably carried out at 20 to 60 °C, more preferably at 25 to 50 °C, and still more preferably at 30 to 45 °C.

[0051] The mixing of the polyol composition and the polyisocyanate is preferably carried out in as short a time as possible. For example, it is preferably within 30 seconds, more preferably within 10 seconds, and still more preferably within 5 seconds from the mixing of the two liquids of the polyol composition and the polyisocyanate to pouring. As a preferred method, a method of continuously supplying and mixing the two liquids of the polyol composition and the polyisocyanate into a mixing chamber and then discharging them can be exemplified.

[0052] Such a mixing method is not particularly limited, and examples include a method of mixing with a stirrer having stirring blades and a method of mixing with a high-pressure mixer.

[0053] When mixing with a stirrer having stirring blades, the rotation speed of the stirring blades is not particularly limited, but the lower limit is preferably 2,000 rpm or more, more preferably 3,000 rpm or more, and still more preferably 5,000 rpm or more.

[0054] High-pressure mixing is a method in which two liquids are supplied at high pressure by a high-pressure mixer and collided and mixed at high speed in a mixing chamber. By mixing in this way, high-viscosity liquids can be mixed. Also, they can be mixed more uniformly in a short time, and more uniform and fine bubbles can be obtained.

[0055] The polyurethane foam formed as described above can be formed, for example, by thermoforming. Thermoforming is a method of compressing and forming the polyurethane foam in a heated mold, and it is possible to densify the foam and form a curved surface. The forming temperature is preferably 220 °C or lower, more preferably 200 °C or lower. The lower limit is not limited, but is, for example, 170 °C or higher. By thermoforming, for example, a cosmetic sponge having a disc shape can be obtained.

Example

[0056] Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.

[0057] Example 1 <Manufacture of Cosmetic Sponge> The following two liquids were prepared. Liquid A: Polyisocyanate Mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate 40 parts by mass Viscosity at 40 °C: 100 mPa·s Liquid B: Polyol composition (Polyol) Polycarbonate diol with a monomer of 3-methyl-1,5-pentanediol and 1,6-hexanediol 40 parts by mass of polycarbonate diol with an average molecular weight of 2000 (※1) Polycarbonate triol with a monomer of 3-methyl-1,5-pentanediol and 1,6-hexanediol 10 parts by mass of polycarbonate triol with an average molecular weight of 3000 (※2) 50 parts by mass of polyether triol with an average molecular weight of 3000 (※3) ※1 Polycarbonate polyol C-2050R manufactured by Kuraray ※2 Polycarbonate polyol CF-1000 manufactured by Kuraray ※3 MN-3050BM manufactured by Mitsui Takeda Chemicals (Sugar alcohol) 2 parts by mass of xylitol (Foaming agent) 1 part by mass of water 1 part by mass of silicone foam stabilizer (Catalyst) 0.1 part by mass of amine catalyst 0.1 part by mass of tin laurate The polyol, sugar alcohol, foaming agent, foam stabilizer, and catalyst were mixed to obtain Liquid B. Liquid B was liquid at 40°C and had a viscosity of 9000 mPa·s.

[0058] Liquid A and Liquid B were each set at 40°C and introduced into a continuous mixer equipped with a rotary stirring blade rotating at 5000 rpm so that the flow rate ratio of Liquid A:Liquid B was 4:10, and they were mixed and stirred. The mixing time was 5 seconds. After mixing, it was poured into a mold and foamed to form a polyurethane foam, and a cosmetic sponge was obtained. The content of xylitol was calculated as 1.4% of the charge.

[0059] Comparative Example 1 A cosmetic sponge was obtained in the same manner as in Example 1 except that xylitol was not contained in Liquid B. Separately, an aqueous solution in which 5% of xylitol was dissolved was prepared, and the obtained cosmetic sponge was immersed to extrude the internal air. Then, the cosmetic sponge was pulled up and wrung so that the weight became 1.5 to 2 times the weight before immersion. The wrung sponge was dried in a dryer set at 60°C for 1 hour. The weights before and after the impregnation treatment were measured, and the amount of xylitol adhered was also calculated.

[0060] <Cooling sensation persistence evaluation> For the cosmetic sponges of Example 1 and Comparative Example 1, the remaining amount of xylitol after washing and the cooling sensation persistence evaluation by sensory evaluation were performed by the following method. The results are shown in Tables 1 and 2.

[0061] (Test method: Remaining amount of xylitol) (1) Washing: 0.5 g of a neutral detergent (coconut fruit detergent) was mixed with 500 ml of water, and the sponge was immersed, and the sponge was evenly pressed and washed 10 times. Then it was wrung 3 times. (2) Rinsing: Immerse the sponge in 500 ml of water and press and wash it 10 times. Then wring it 3 times. Perform this twice. (3) Drying: Dry the wrung sponge in a dryer set at 60 °C for 1 hour. (4) Measure the weight before and after the test.

[0062] (Test method: Sensory evaluation) Regarding the sponges before and after washing, sensory evaluations were conducted by 10 professional panels for cosmetics evaluation. Each sponge was impregnated with twice its own weight of water, and the inner forearm was slid across it to score how "cool it felt" according to the following evaluation criteria, and the average score was obtained. (Evaluation criteria) [Score]: [Evaluation] 5 points: Feels very cool 4 points: Feels slightly cool 3 points: Neither can be said 2 points: Doesn't feel very cool 1 point: Doesn't feel cool at all

[0063]

Table 1

[0064]

Table 2

[0065] From these results, it was shown that the cosmetic sponge of Example 1 had excellent cold feeling persistence compared to Comparative Example 1. Also, the cosmetic sponge of Example 1 was good in terms of flexibility, elasticity, texture, etc.

Industrial applicability

[0066] The present invention is useful as a cosmetic sponge having excellent cold feeling persistence.

Claims

1. A cosmetic sponge formed from a urethane resin composition obtained by mixing a polyol composition containing a polyol and a sugar alcohol with a polyisocyanate.

2. The cosmetic sponge according to claim 1, wherein the sugar alcohol is one or more selected from the group consisting of sorbitol, mannitol, xylitol, and erythritol.

3. The cosmetic sponge according to claim 1 or 2, wherein the polyol composition contains 0.1 to 10 parts by mass of the sugar alcohol per 100 parts by mass of the polyol.

4. The cosmetic sponge according to claim 1 or 2, wherein the polyol composition further contains a foaming agent.

5. The cosmetic sponge according to claim 1 or 2, wherein the polyol composition further contains a catalyst.

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