Leave-on formulation

Abstract

To provide a leave-on preparation excellent in bactericidal and / or virucidal properties and their persistent effects.SOLUTION: The leave-on preparation comprises (A) one or more polyols selected from the group consisting of 1, 2-hexanediol, 2-ethyl-1, 3-hexanediol and 3 - (2-ethylhexyloxy) - 1, 2-propanediol and (B) lactic acid or its salt.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a leave-on preparation that protects the skin from bacteria or viruses. [Background technology]

[0002] Recent studies have shown that contact infection is a common route of bacterial or viral infection in people's daily lives. Contact infection occurs primarily when hands come into contact with infected people, doorknobs, handles, tableware, toys, other household items, interior decorations, and other objects.

[0003] There is a need for a method to prevent bacterial or viral infections caused by contact in such everyday life. As a method for preventing contact infection of bacteria or viruses via hands, a method of applying an alcohol-based disinfectant to hands to sterilize and disinfect them is known. However, alcohols such as ethanol used as sterilizing or disinfecting components are highly volatile, and the effect is not sufficiently sustained in terms of imparting a bactericidal and / or virucidal effect to hands.

[0004] Therefore, methods for providing hands with a defense function against bacteria or viruses have been studied. These methods continuously provide a bacterial or viral infection prevention effect, making it possible to prevent contact infection even in environments where there is no hand-washing facility, such as when out and about. This is particularly preferable because it can prevent infection even when repeatedly coming into contact with an object that has bacteria or viruses attached.

[0005] For example, Patent Document 1 discloses a method for inhibiting bacteria and viruses present on the skin surface of a mammal, which comprises contacting the skin for at least about 0.5 hours with a compound or composition capable of reducing the skin pH to less than about 4. It also discloses that the compound or composition capable of reducing the skin pH further contains an antimicrobial agent selected from the group consisting of phenolic antibacterial agents, quaternary ammonium antimicrobial agents, anilides, bisguanidines, and mixtures thereof.

[0006] Additionally, compositions for sterilizing the skin that contain a bactericide or antibacterial agent are known (for example, Patent Document 2). Patent Document 2 discloses that a long-lasting antiseptic cream for disinfection contains a cationic antiseptic, a lower alcohol, an oily base, a higher aliphatic alcohol, a lipophilic and hydrophilic nonionic surfactant, a water-soluble polyhydric alcohol, and purified water, and has a long-lasting disinfecting effect on the skin, hands, and traumatic wounds, as well as an effect of preventing rough hands. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-284412 [Patent Document 2] Special Publication No. 2008-523064 Summary of the Invention [Problem to be solved by the invention]

[0008] Cationic disinfectants such as benzalkonium chloride are commonly used in disinfectants for skin, such as for hands and fingers. However, the inventors' studies have revealed that, compared with inorganic materials such as stainless steel and glass, it is difficult to achieve a bactericidal effect on the surface of human skin using conventional disinfectants, such as cationic disinfectants. Furthermore, the amount of disinfectant and antibacterial agent to be incorporated into a skin composition may be substantially limited from the standpoint of safety to the human body, etc. Therefore, the bactericidal and / or virucidal activity and sustained effect of the disinfectant or antibacterial agent on the skin are insufficient, and further improvement is desired. Furthermore, in Patent Document 2, a bactericidal disinfectant is applied to undisinfected hands after hand washing, and the reduction rate of the number of bacteria after disinfection relative to the number of bacteria before disinfection is evaluated. However, no study was conducted on whether a protective function against bacteria or viruses can be imparted to hands in advance, and whether a bactericidal and / or virucidal effect can be sustained when bacteria or viruses subsequently adhere to the hands, and in this respect there is room for improvement.

[0009] The present invention relates to a leave-on preparation that protects the skin from bacteria or viruses, and has excellent bactericidal and / or virucidal activity and a long-lasting effect. [Means for solving the problem]

[0010] The present inventors have found that the above-mentioned problems can be solved by applying a polyol that satisfies certain requirements or a composition containing the same to the skin in such a manner that the amount of the polyol applied falls within a certain range. That is, the present invention provides a method for applying a polyol (A) satisfying the ratio (number of OH groups / number of carbon atoms) of less than 1 or a composition containing the polyol (A) to 1 cm of skin in an amount of 1 cm. 2 The present invention relates to a method for protecting the skin from bacteria or viruses, which comprises a step of applying a composition to the skin so that the amount of the composition is 0.0005 mg or more and 1.0 mg or less per unit area. Furthermore, a leave-on formulation according to another embodiment of the present invention contains one or more polyols (A) selected from the group consisting of 1,2-hexanediol, 2-ethyl-1,3-hexanediol, and 3-(2-ethylhexyloxy)-1,2-propanediol, and lactic acid or a salt thereof (B). [Effects of the Invention]

[0011] According to the present invention, a leave-on preparation that protects the skin from bacteria or viruses and has excellent bactericidal and / or virucidal properties and a long-lasting effect can be provided. DETAILED DESCRIPTION OF THE INVENTION

[0012] [Methods for protecting the skin from bacteria or viruses] The method of the present invention for protecting the skin from bacteria or viruses (hereinafter also referred to as "the method of the present invention") comprises applying a polyol (A) satisfying the ratio (number of OH groups / number of C atoms) of less than 1 or a composition containing the polyol (A) to an area of ​​1 cm of the skin. 2 The method includes a step of applying the compound to the skin so that the amount of the compound reaches 0.0005 mg or more and 1.0 mg or less per unit area. The method of the present invention has the above-mentioned features, and therefore has excellent bactericidal and / or virucidal properties on the skin surface and a sustained effect thereof.

[0013] The reason why the method of the present invention exhibits the above-mentioned effects is not clear, but is thought to be as follows. As described above, the inventors' investigations have revealed that it is difficult to obtain a bactericidal effect from conventional disinfectants on the surface of human skin. This is thought to be because the skin is negatively charged, and when a cationic disinfectant such as benzalkonium chloride is applied, the charge is offset, reducing the bactericidal and / or virucidal properties of the disinfectant. Therefore, the present inventors focused on polyols as a component that can effectively exert bactericidal and / or virucidal properties even on the skin surface. The polyol component (A) is a polyol that satisfies the relationship (number of OH groups / number of C atoms) < 1, and has a hydrophilic hydroxyl group and a hydrophobic portion containing a C atom. The hydrophilic portion of component (A) has a high affinity for water molecules and forms an interaction with them, while the hydrophobic portion distorts or destroys the three-dimensional hydrogen bond network of water. This has the same effect as ethanol, etc. This destruction of the three-dimensional hydrogen bond network of water transforms the aqueous environment surrounding bacteria and viruses. This change is thought to have the effect of denaturing, for example, hydrophilic membrane proteins. Furthermore, component (A) is less volatile than lower monoalcohols such as ethanol, and can remain near the skin surface at high concentrations for a long time after application to the skin, which is thought to result in excellent sustained bactericidal and / or virucidal effects.

[0014] In this specification, "protecting the skin from bacteria or viruses" encompasses concepts such as (1) a bactericidal and / or virucidal effect exerted against bacteria and viruses adhering to the skin surface after applying polyol (A) or a composition containing it to the skin surface, (2) a bactericidal and / or virucidal effect exerted against bacteria and viruses adhering to the skin by applying polyol (A) or a composition containing it, (3) an effect of preparing the skin so that bacteria and viruses are not transmitted through it, (4) an effect of protecting the skin from bacteria and viruses and keeping it hygienic, (5) an effect of preventing the spread of bacteria and viruses through the skin and contact infection, and (6) an effect of enhancing the skin's ability to defend against infections from bacteria and viruses.

[0015] Furthermore, unlike techniques for sterilizing and / or killing viruses with ethanol or the like, the method of the present invention allows component (A) to remain on the skin surface and can impart continuous bactericidal and / or virucidal properties to the skin surface, making it a particularly useful technique for leave-on preparations that leave component (A) on the skin surface. That is, in the method of the present invention, after component (A) or a composition containing it is applied to the skin by application or the like, it is preferable that component (A) is left on the skin surface without being removed by washing with water or the like.

[0016] The bacteria or viruses that are the target of the method of the present invention to exhibit bactericidal and / or virucidal properties are not particularly limited as long as they are inactivated or killed by contact with component (A), and it is considered that, for example, microorganisms listed in the Ministry of Health, Labor and Welfare's guidelines for infectious disease control in nurseries can be applied. Specific examples of bacteria include gram-positive bacteria such as Bacillus anthracis, Mycobacterium tuberculosis, hemolytic streptococcus, Staphylococcus aureus, and Streptococcus pneumoniae, as well as gram-negative bacteria such as Francisella tularensis, Yersinia pestis, Brucella, Bacillus mallei, Vibrio cholerae, Salmonella enterica, Shigella, enterohemorrhagic Escherichia coli, and Bordetella pertussis. Examples of viruses include enveloped viruses such as arenaviruses, Ebola viruses, smallpox viruses, nairoviruses, Marburg viruses, coronaviruses, monkeypox viruses, betacoronaviruses, influenza viruses, respiratory syncytial viruses, herpes viruses, mumps viruses, varicella-zoster viruses, rubella viruses, and measles viruses, as well as non-enveloped viruses such as enteroviruses, adenoviruses, coxsackieviruses, noroviruses, and rotaviruses. In this example, the bactericidal activity is evaluated using Serratia marcescens as an example, but the bacteria or viruses targeted by the method of the present invention are not limited to this.

[0017] <Component (A): Polyol> The method of the present invention comprises the step of applying to the skin a polyol (A) or a composition containing the polyol (A) that satisfies the ratio (number of OH groups / number of C atoms) of less than 1. Component (A) itself acts as a bactericidal and / or virucidal component.

[0018] From the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect, the (number of OH groups / number of C atoms) of component (A) is less than 1, and is preferably 0.95 or less, more preferably 0.80 or less, even more preferably 0.70 or less, still more preferably 0.60 or less, still more preferably 0.50 or less, still more preferably 0.40 or less, still more preferably 0.35 or less, and is also preferably 0.15 or more, more preferably 0.18 or more, still more preferably 0.20 or more, and still more preferably 0.23 or more.

[0019] From the viewpoint of improving bactericidal and / or virucidal properties and their sustained effects, component (A) is used in IR measurements, with the vertical axis representing absorbance and the horizontal axis representing wave number (cm -1 ) the wave number of the peak top due to OH stretching vibration is preferably 3300 cm -1 More than 3318cm, preferably -1 and is usually 3452 cm -1 This is because it is believed that the higher the peak top wavenumber is on the side of higher wavenumbers, the more likely it is that the effect of distorting or destroying the three-dimensional hydrogen bond network of water can be obtained. The IR measurement of component (A) can be specifically carried out by the method described in the examples.

[0020] From the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect, component (A) preferably has a logPow value of −2.5 or more, more preferably −1.0 or more, even more preferably 0 or more, and still more preferably 0.5 or more. This is because it is believed that the higher the logPow value, the higher the hydrophobicity of component (A), making it easier to obtain the effect of distorting or destroying the three-dimensional hydrogen bond network of water. where: Pow: The concentration ratio of component (A) in the two solvent phases of 1-octanol and water when component (A) is added to the two solvent phases and reaches equilibrium. logPow = log10 (concentration of component (A) in 1-octanol phase / concentration of component (A) in aqueous phase) is. The logPow value of component (A) can be calculated using the algorithm "XLOGP3" described in Renxiao Wang et al., J. Chem. Inf. Model. 2007, Vol. 47, pp. 2140.

[0021] The number of carbon atoms in component (A) is preferably 3 or more, more preferably 4 or more, from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect, and is preferably 24 or less, more preferably 20 or less, even more preferably 16 or less, still more preferably 12 or less, still more preferably 11 or less, and still more preferably 8 or less, from the viewpoint of improving bactericidal and / or virucidal properties by distorting or destroying the three-dimensional hydrogen bond network of water. Furthermore, the number of OH groups in component (A) is preferably 2 or more and 5 or less, more preferably 2 or more and 4 or less, and even more preferably 2 or more and 3 or less, from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect.

[0022] Specific examples of component (A) include linear polyols and polyols having a cyclic structure, and either of these can be used. Component (A) is preferably a linear polyol from the viewpoint of improving bactericidal and / or virucidal properties by distorting or destroying the three-dimensional hydrogen bond network of water, and is more preferably a linear polyol having 3 or more carbon atoms, and even more preferably a linear diol or triol having 3 or more carbon atoms, from the viewpoint of improving bactericidal and / or virucidal properties by having a hydrophobic portion and from the viewpoint of sustained bactericidal and / or virucidal properties. In the linear polyol, the bonding position of the OH group is not particularly limited.

[0023] Examples of the chain polyol used as component (A) include propylene glycol (1,2-propanediol), 1,3-propanediol, dipropylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,3-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 2,5-hexanediol, 1,6-hexanediol, and 1,6-hexanediol. linear diols such as xanediol, 1,2-heptanediol, 1,7-heptanediol, 1,2-octanediol, 1,8-octanediol, 1,2-nonanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1,2-dodecanediol, 1,12-dodecanediol, 1,2-tetradecanediol, 1,2-hexadecanediol, and 1,16-hexadecanediol; linear triols such as 1,2,3-butanetriol, 1,2,4-butanetriol, 1,2,5-pentanetriol, 1,2,6-hexanetriol, 1,2,7-heptanetriol, 1,2,8-octanetriol, 1,2,9-nonanetriol, and 1,2,10-decanetriol; Branched diols or triols such as 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,3-butanediol, 2-methylpentane-2,4-diol, 2-ethyl-1,3-hexanediol, tripropylene glycol, 2-butyl-2-ethyl-1,3-propanediol, 3-(2-ethylhexyloxy)-1,2-propanediol, (lauryl / myristyl) glycol hydroxypropyl ether, 3,7,11,15-tetramethylhexadecane-1,2,3-triol; and Polymers such as polyethylene glycol, polyglycerin, and PPG-10 butanediol; and the like, and one or more of these can be used.

[0024] Among the above, from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect, component (A) is preferably propylene glycol, dipropylene glycol, 1,3-butylene glycol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,2-octanediol, 1,8-octanediol, 1,2-nonanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1,2-dodecanediol, 1,12-dodecanediol, 1,2,6-hexanetriol, 1,2,10-decanetriol, 2-methylpentane-2,4-diol, 2-ethyl-1,3-hexanediol, 3-(2-ethylhexyloxy)-1,2-propanediol, The alkyl acrylate copolymer is preferably one or more selected from the group consisting of dipropylene glycol, 1,3-butylene glycol, 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol, 1,2-nonanediol, 1,2-dodecanediol, 1,2,10-decanetriol, 2-ethyl-1,3-hexanediol, and 3-(2-ethylhexyloxy)-1,2-propanediol, and more preferably one or more selected from the group consisting of dipropylene glycol, 1,2-hexanediol, 1,2-octanediol, 2-ethyl-1,3-hexanediol, and 3-(2-ethylhexyloxy)-1,2-propanediol.

[0025] <Composition containing component (A)> In the method of the present invention, component (A) may be applied to the skin alone. However, from the viewpoint of ease of application to the skin, it is preferable to prepare a composition containing component (A) and apply the composition to the skin. When a composition containing component (A) is used in the method of the present invention, the content of component (A) in the composition is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.2% by mass or more, and still more preferably 0.5% by mass or more, from the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect. Also, from the viewpoint of improving the feel of the composition when used, the content is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, still more preferably 10% by mass or less, still more preferably 5.0% by mass or less, still more preferably 4.0% by mass or less, and still more preferably 3.0% by mass or less.

[0026] (water) The composition preferably further contains water from the viewpoint of dissolving component (A) and facilitating application to a target object such as the skin surface. The content of water in the composition is preferably 25% by mass or more, more preferably 50% by mass or more, even more preferably 70% by mass or more, and is preferably 99.9% by mass or less.

[0027] From the viewpoint of obtaining the effects of the present invention, the total content of component (A) and water in the composition is preferably 25% by mass or more, more preferably 50% by mass or more, even more preferably 70% by mass or more, still more preferably 90% by mass or more, still more preferably 95% by mass or more, and may be 100% by mass.

[0028] In addition to component (A), the composition may contain a polyol (hereinafter also referred to as "component (A')") such as glycerin, which satisfies the (number of OH groups / number of carbon atoms) ratio of ≥ 1, provided that the effects of the present invention are not impaired. When the composition contains component (A'), from the viewpoint of moisturizing properties, its content in the composition is preferably 0.025% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, even more preferably 0.15% by mass or more, even more preferably 0.25% by mass or more, even more preferably 0.35% by mass or more, and even more preferably 0.5% by mass or more. Furthermore, from the viewpoint of improving the feel of the composition when used, it is preferably 10% by mass or less, more preferably 7.0% by mass or less, even more preferably 5.0% by mass or less, even more preferably 2.5% by mass or less, even more preferably 2.0% by mass or less, and even more preferably 1.5% by mass or less. Furthermore, the proportion of component (A) in all polyols contained in the composition (content of component (A) / total polyol content × 100) is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more, but 100% by mass or less.

[0029] (Component (B): organic acid or its salt) The composition may further contain an organic acid or a salt thereof as component (B) in order to improve the bactericidal and / or virucidal properties and their sustained effect. Examples of the organic acid include lactic acid, pyruvic acid, urocanic acid, acetic acid, glycolic acid, malic acid, tartaric acid, citric acid, succinic acid, fumaric acid, and adipic acid, and one or more of these can be used. From the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect, and from the viewpoint of low skin irritation, the organic acid is preferably one or more selected from the group consisting of lactic acid, pyruvic acid, and urocanic acid. Examples of salts of lactic acid, pyruvic acid, and urocanic acid include alkali metal salts of lactic acid or pyruvic acid, such as potassium salts and sodium salts; alkaline earth metal salts, such as calcium salts and magnesium salts; amine salts; ammonium salts, etc. Among these, from the viewpoints of improving bactericidal and / or virucidal properties and easy availability, one or more selected from the group consisting of alkali metal salts and alkaline earth metal salts of lactic acid, pyruvic acid, and urocanic acid are preferred, one or more selected from the group consisting of potassium salts, sodium salts, and calcium salts are more preferred, and one or more selected from the group consisting of potassium lactate, sodium lactate, and calcium lactate are even more preferred. From the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect, component (B) is more preferably lactic acid or a salt thereof, more preferably one or more selected from the group consisting of lactic acid, potassium lactate, sodium lactate, and calcium lactate, and even more preferably lactic acid.

[0030] When the composition contains component (B), the content of component (B) in the composition is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, from the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect. Also, from the viewpoint of suppressing skin irritation and economical efficiency, the content is preferably 10.0% by mass or less, more preferably 5.0% by mass or less, even more preferably 3.0% by mass or less, and even more preferably 2.0% by mass or less. In this specification, when component (B) contains a salt, the "content of component (B)" means the amount converted into the acid.

[0031] Furthermore, when the composition contains component (B), the mass ratio (B / A) of component (B) to component (A) contained in the composition is preferably 0.05 or more, more preferably 0.1 or more, even more preferably 0.5 or more, and still more preferably 1.0 or more, from the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect. Furthermore, from the viewpoint of suppressing skin irritation, it is preferably 30 or less, more preferably 20 or less, even more preferably 25 or less, and still more preferably 10 or less.

[0032] (Component (C): Surfactant) The composition may further contain, as component (C), one or more surfactants selected from the group consisting of nonionic surfactants and anionic surfactants, in order to improve the bactericidal and / or virucidal properties and their sustained effect.

[0033] Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkenyl ethers, sucrose fatty acid esters, polyoxyethylene fatty acid esters, polyglyceryl alkyl ethers, fatty acid polyglyceryl, sorbitan fatty acid esters, alkyl glucosides, polyoxyethylene alkylamines, polyoxyethylene sorbitan fatty acid esters, and polyoxyethylene sorbit fatty acid esters, and one or more of these can be used.

[0034] Of the above, the alkyl group in the polyoxyethylene alkyl ether, polyglyceryl alkyl ether, alkyl glucoside, and polyoxyethylene alkylamine, the alkenyl group in the polyoxyethylene alkenyl ether, and the fatty acid in the sucrose fatty acid ester, polyoxyethylene fatty acid ester, fatty acid polyglyceryl, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, and polyoxyethylene sorbit fatty acid ester preferably has from 8 to 22 carbon atoms, more preferably from 10 to 22 carbon atoms, and even more preferably from 10 to 18 carbon atoms, from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect.

[0035] Furthermore, the average number of moles of oxyethylene groups added in polyoxyethylene alkyl ethers, polyoxyethylene alkenyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, polyoxyethylene sorbitan fatty acid esters, and polyoxyethylene sorbit fatty acid esters (hereinafter referred to as "average number of moles of EO added") is, from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effects, preferably 2 or more, more preferably 3 or more, and is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less. The average number of moles of EO added is a number average value.

[0036] Examples of anionic surfactants include alkylbenzenesulfonates, alkyl or alkenyl ether sulfates, alkyl or alkenyl sulfates, alkyl sulfonates, saturated or unsaturated fatty acid salts, alkyl or alkenyl ether carboxylates, α-sulfofatty acid salts, N-acylamino acids, mono- or diester phosphates, and sulfosuccinates, and one or more of these can be used. Examples of counter ions of the anionic groups in the anionic surfactants include alkali metal ions such as sodium ions and potassium ions; alkaline earth metal ions such as calcium ions and magnesium ions; ammonium ions; and alkanolammoniums having 1 to 3 alkanol groups with 2 or 3 carbon atoms (e.g., monoethanolammonium, diethanolammonium, triethanolammonium, triisopropanolammonium, etc.). Among the above, one or more selected from the group consisting of alkyl sulfates, alkyl ether sulfates, and alkyl ether carboxylates are preferred. Examples of the alkyl ether sulfates include polyoxyethylene alkyl ether sulfates such as sodium laureth sulfate, and examples of the alkyl ether carboxylates include polyoxyethylene alkyl ether acetates such as sodium laureth acetate.

[0037] One or more types of component (C) can be used. Among the above, from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect, nonionic surfactants are preferred as component (C), and one or more selected from the group consisting of polyoxyethylene alkyl ethers, polyoxyethylene alkenyl ethers, sucrose fatty acid esters, polyoxyethylene fatty acid esters, polyglyceryl alkyl ethers, fatty acid polyglyceryls, alkyl glucosides, and polyoxyethylene alkylamines are preferred, one or more selected from the group consisting of polyoxyethylene alkyl ethers, polyoxyethylene alkenyl ethers, and polyoxyethylene fatty acid esters are more preferred, and polyoxyethylene alkyl ethers are even more preferred.

[0038] When the composition contains component (C), the content of component (C) in the composition is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more from the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect, and is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, and even more preferably 1.0% by mass or less from the viewpoint of suppressing skin irritation and economic efficiency.

[0039] (fungicide) The composition uses component (A) as a bactericidal and / or virucidal component, but may further contain a bactericide from the viewpoint of improving bactericidal and / or virucidal properties and their sustained effect. From the viewpoint of application to the skin, the disinfectant is preferably one or more selected from the group consisting of cationic disinfectants, iodine-based disinfectants, phenol-based disinfectants, dipotassium glycyrrhizinate, stearyl glycyrrhetinate, salicylic acid, and biguanide-based disinfectants. Examples of cationic disinfectants include quaternary ammonium salt compounds such as cetylpyridinium chloride, benzethonium chloride, and benzalkonium chloride. Examples of iodine-based disinfectants include povidone iodine, polyvinyl alcohol iodine, and cyclodextrin iodine. Examples of phenolic disinfectants include isopropylmethylphenol, triclosan, and phenoxyethanol. Examples of biguanide disinfectants include chlorhexidine gluconate. From the viewpoint of further improving the bactericidal and / or virucidal properties and their sustained effect, the bactericide is more preferably one or more selected from the group consisting of cationic bactericides, iodine-based bactericides, phenol-based bactericides, and biguanide-based bactericides, even more preferably one or more selected from the group consisting of benzalkonium chloride, benzethonium chloride, povidone-iodine, and chlorhexidine gluconate, and even more preferably benzalkonium chloride.

[0040] When the composition contains a bactericide, the content of the bactericide in the composition is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and even more preferably 0.03% by mass or more from the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect. Also, from the viewpoint of suppressing skin irritation and economic efficiency, the content is preferably 10% by mass or less, more preferably 5.0% by mass or less, even more preferably 3.0% by mass or less, still more preferably 1.0% by mass or less, still more preferably 0.5% by mass or less, still more preferably 0.2% by mass or less, and even more preferably 0.1% by mass or less.

[0041] (Other ingredients) In addition to the above, the composition may contain other ingredients, if necessary, such as a thickener, a pH adjuster (hydrochloric acid, sodium hydroxide, etc.), an ultraviolet absorber, an antioxidant, a preservative, an antiperspirant, a fragrance, a moisturizer, a texture adjuster, an anti-inflammatory agent, etc.

[0042] Because the composition uses component (A) as a bactericidal and / or virucidal component, it exhibits bactericidal and / or virucidal properties without blending a monoalcohol having 4 or fewer carbon atoms, such as ethanol or isopropanol. Furthermore, from the viewpoint of suppressing skin irritation, the content of the monoalcohol having 4 or fewer carbon atoms in the composition is preferably 15% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, still more preferably 3% by mass or less, even more preferably 1% by mass or less, still more preferably 0.07% by mass or less, even more preferably 0.05% by mass or less, still more preferably 0.03% by mass or less, still more preferably less than 0.01% by mass, and most preferably substantially 0% by mass.

[0043] The composition preferably contains a small amount of oily components, from the viewpoint of not inhibiting contact between component (A) and bacteria or viruses and achieving bactericidal and / or virucidal properties and their sustained effects. In this specification, oily components refer to oily agents with a solubility of less than 0.01 g in 100 g of water at 20°C, such as silicone oils, ester oils, ether oils, hydrocarbon oils, fatty acids with 12 or more carbon atoms, and higher alcohols with 12 or more carbon atoms. From the viewpoint of obtaining bactericidal and / or virucidal properties and their sustained effect, the content of the oily component in the composition is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably less than 2% by mass, still more preferably 1% by mass or less, even more preferably 0.5% by mass or less, even more preferably 0.2% by mass or less, still more preferably 0.1% by mass or less, still more preferably 0.05% by mass or less, and may even be 0% by mass.

[0044] (pH) The composition has a pH at 25°C of preferably 3.5 or higher, more preferably 3.7 or higher, and even more preferably 4.0 or higher, from the viewpoint of suppressing skin irritation. Also, from the viewpoint of suppressing skin irritation, the pH is preferably less than 10, more preferably 8.0 or lower, and even more preferably 7.5 or lower. On the other hand, when the composition contains an organic acid or a salt thereof (B), the pH is preferably 5.0 or lower, and even more preferably 4.5 or lower, from the viewpoint of improving bactericidal and / or virucidal activity and its sustained effect. The pH is measured at 25° C., and can be measured by the method described in the Examples.

[0045] The form of the composition is not particularly limited, and may be, for example, a solid, liquid, gel, or cream. From the viewpoint of ease of application to the skin, the composition is preferably in the form of a gel or cream. The composition may be in the form of an emulsion composition, and the emulsion composition may be either an oil-in-water emulsion composition or a water-in-oil emulsion composition.

[0046] When the composition is a leave-on preparation, its dosage form may be, for example, a stick preparation comprising a solid composition; a roll-on preparation or a spray preparation filled with a liquid composition; a preparation in which a liquid, gel, or cream composition is filled in a bottle, tube, dispenser-type container, or the like; a sheet product impregnated with the composition; and the like.

[0047] <Step of applying component (A) or composition> The method of the present invention comprises applying component (A) or the composition containing the same to an area of ​​1 cm of skin. 2 The method includes a step of applying the compound to the skin so that the amount of the compound reaches 0.0005 mg or more and 1.0 mg or less per unit area. In order to impart high bactericidal and / or virucidal activity and its persistence, the amount of component (A) applied in this step is set to 1 cm of skin. 2The amount is preferably 0.001 mg or more, more preferably 0.002 mg or more, even more preferably 0.005 mg or more, still more preferably 0.01 mg or more, and even more preferably 0.02 mg or more, per unit weight, and from the viewpoint of suppressing skin irritation and economic efficiency, the amount is preferably 0.5 mg or less, more preferably 0.3 mg or less, and even more preferably 0.2 mg or less.

[0048] The method for applying the composition containing component (A) to the skin can be selected depending on the formulation of the composition, the area to be applied, etc. For example, the composition can be applied by painting or spraying it onto the skin. The body part to which the composition is applied is not particularly limited, and it can be applied to any body part, such as the fingers, upper arms, lower legs, neck, trunk, etc. From the viewpoint of blocking the route of infection and transmission of bacteria and viruses through human-to-human and object-to-human contact, it is preferable to apply it to the hands and fingers, which are frequently in contact with public objects and one's own nose and mouth in daily life. In the method of the present invention, after applying component (A) or the composition to the skin, it is preferable to leave component (A) on the skin surface without rinsing with water, etc. This is because by leaving component (A), a bactericidal and / or virucidal component, on the skin surface, bactericidal and / or virucidal properties can be imparted to the skin surface.

[0049] Component (A) or the composition may be applied to unwashed skin after previously washing the skin with water, soap, body soap, hand soap, etc. After washing, naturally occurring components such as lactic acid are washed away from the skin, and the skin's defense against external bacteria and viruses is weakened. Therefore, it is more preferable to carry out the method of the present invention by applying component (A) or the composition to washed skin. [Example]

[0050] The present invention will be described below with reference to examples, but the present invention is not limited to the scope of the examples. In the examples, various measurements and evaluations were carried out by the following methods.

[0051] (pH) The pH of the composition was measured at 25°C using a pH meter (electrode: 6367-10D (manufactured by Horiba Ltd.)).

[0052] (IR measurement) The polyols listed in Table 1 were used as measurement samples, and IR measurements were carried out by the ATR method using an infrared spectrophotometer (PerkinElmer "Spectrum 400, Universal ATR unit"), with a diamond / ZnSe crystal and a resolution of 4 cm. -1 , 16 times accumulation, 4000~650cm -1 The measurements were carried out in a range of 22°C room temperature and 35% RH. The vertical axis of the chart represents absorbance, and the horizontal axis represents wavenumber (cm -1 ) as 3250~3452cm -1 The wavenumber of the peak top in the range of OH stretching vibration (cm -1 ) are shown in Table 1. (logPow value) The logPow values ​​of polyols listed in Table 1 are literature values ​​if they have a footnote in Table 1. If they do not have a footnote in Table 1, they are values ​​quoted from the chemical substance database "PubChem" and calculated using the aforementioned algorithm "XLOGP3."

[0053] (Preparation of bacterial solution) For the evaluation of bactericidal activity, a Serratia bacterial solution prepared by the following method was used. The NBRC12648 strain was used as the Serratia marcescens. This bacterium was cultured in LB liquid medium, and the cells were collected by centrifugation. The OD 600 was adjusted to be 10. (Bactericidal evaluation) [a. Bactericidal activity (log reduction) immediately after application of the composition] The inner forearm of each subject was washed with "Biore u Rg" (manufactured by Kao Corporation). After waiting for 5 to 10 minutes, the compositions shown in Tables 2 and 3 were applied to the skin surface of the inner forearm (7.5 cm -1In Comparative Examples 2 and 3, the coating was applied to the stainless steel surface and the glass surface, respectively, and spread evenly to the application amounts shown in each table. After leaving the composition to stand for 5 minutes and drying, a fixed amount (7.5 μL / 7.5 cm ) of the Serratia marcescens solution prepared by the above method was applied to the skin surface after application of the composition. -1 After leaving the sample in this state for a predetermined time (the "contact time with bacteria" shown in the table), the applied bacterial solution was collected using two swabs. Next, the number of viable bacteria was measured by the following method using an incubation reader "HiTS" (manufactured by Synix Co., Ltd.), and the reduction in the number of bacteria (number of viable bacteria / initial number of viable bacteria) was confirmed. Liquid culture was performed at 37°C in an incubation reader "HiTS," and the absorbance (turbidity) at a wavelength of 600 nm was measured over time to create a growth curve of the number of viable bacteria in the bacterial solution. At the same time, a bacterial solution with a known number of viable bacteria was serially diluted, and similarly cultured and a growth curve was created, creating a calibration curve of the time to reach a certain turbidity and the number of viable bacteria. From the relationship between the time to reach a certain turbidity for each sample and the calibration curve, the number of viable bacteria in the collected bacterial solution was estimated, and the reduction in the number of bacteria was confirmed. The degree of reduction in the number of bacteria (logarithmic reduction value) was calculated by taking the -log value of the reduction in the number of bacteria, and is shown as "Evaluation result a" in Tables 2 to 5. The larger this value, the higher the bactericidal activity.

[0054] [b. Evaluation of the persistence of the composition: bactericidal activity after time (log reduction)] The same procedure as in a. above was carried out, except that the standing time (5 minutes) after application of the composition shown in Table 2 to the object to be treated was changed to the "standing time for evaluating sustainability" shown in each table. The degree of reduction in the number of bacteria (logarithmic reduction value) was calculated as the -log value of the reduction in the number of bacteria, and this is shown as "Evaluation result b" in Table 2. The larger this value, the higher the bactericidal activity.

[0055] [c. Bactericidal activity (log reduction) immediately after application of a composition (pure water or ethanol) without any added ingredients] Using pure water or ethanol instead of the compositions shown in Tables 2 to 5, the bactericidal activity was evaluated in the same manner as in a. above (evaluation result c).

[0056] [d. Evaluation of persistence of the composition (pure water) without added ingredients: bactericidal activity (log reduction value) after time has passed] Pure water was used instead of the composition shown in Table 2, and the bactericidal activity was evaluated in the same manner as in c. above (evaluation result d).

[0057] Furthermore, the difference (ac) between evaluation results a and c, and the difference (bd) between evaluation results b and d were calculated and are shown in Tables 2 to 5. The larger the value of (ac), the greater the bactericidal effect immediately after application of the composition (initial stage), and the larger the value of (bd), the greater the bactericidal effect even after some time has passed since application of the composition.

[0058] Examples 1 to 15 and Comparative Examples 1 to 4 (Preparation and Evaluation of Compositions) The components were blended in the amounts shown in Tables 2 to 5, mixed at room temperature, and then the pH was adjusted to the value shown in each table using a 1 mol / L aqueous hydrochloric acid solution and / or a 1 mol / L aqueous sodium hydroxide solution as a pH adjuster to prepare the compositions. The blending amounts shown in Tables 2 to 5 are the amount of active ingredient (% by mass) of each component. The resulting compositions were evaluated for bactericidal activity by the above-mentioned method. The results are shown in Tables 2 to 5. Details of component (A) used in Tables 2 to 5, and component (A'), a polyol other than component (A), are shown in Table 1.

[0059] [Table 1]

[0060] [Table 2]

[0061] [Table 3]

[0062] [Table 4]

[0063] [Table 5]

[0064] *1: Dipropylene glycol "Dipropylene glycol (mixture of isomers)" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. *2: 3-(2-ethylhexyloxy)-1,2-propanediol, manufactured by Tokyo Chemical Industry Co., Ltd. *3: Glycerol "Glycerin" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. *4: Benzalkonium chloride "Benzalkonium chloride (50% aqueous solution)" manufactured by Tokyo Chemical Industry Co., Ltd. *5: 2-Ethyl-1,3-hexanediol "2-Ethyl-1,3-hexanediol (mixture of isomers)" manufactured by Tokyo Chemical Industry Co., Ltd. *6: 1,2-Hexanediol, manufactured by Tokyo Chemical Industry Co., Ltd. *7: Lactic acid Fujifilm Wako Pure Chemical Industries, Ltd. "Lactic acid (active: 90%)" *8: 1,2-octanediol manufactured by Tokyo Chemical Industry Co., Ltd. *9: 1,2-Nonanediol manufactured by Tokyo Chemical Industry Co., Ltd. *10: 1,2-Dodecanediol, manufactured by Tokyo Chemical Industry Co., Ltd. *11: Ethanol Fujifilm Wako Pure Chemical Industries, Ltd. "Ethanol (99.5)"

[0065] Tables 2 to 5 show that the method of this example is excellent in bactericidal properties and its sustained effect. Furthermore, a comparison of Comparative Example 1 with Comparative Examples 2 and 3 in Table 2 shows that when the composition is applied to skin, it is difficult for the disinfectant to achieve bactericidal properties compared to stainless steel or glass. Furthermore, a comparison of Example 1 and Comparative Example 1 in Table 2 shows that Example 1 has better bactericidal properties and longer-lasting effects than Comparative Example 1, in which a composition containing a known bactericide was applied to the skin. Also, a comparison of Example 1 and Comparative Example 4 in Table 2 shows that even when a polyol that does not satisfy the specified requirements is used, the bactericidal properties are lower than those of the method of this example. [Industrial Applicability]

[0066] According to the present invention, a leave-on preparation that protects the skin from bacteria or viruses and has excellent bactericidal and / or virucidal properties and a long-lasting effect can be provided.

Claims

1. A leave-on preparation comprising (A) one or more polyols selected from the group consisting of 1,2-hexanediol, 2-ethyl-1,3-hexanediol, and 3-(2-ethylhexyloxy)-1,2-propanediol, and (B) lactic acid or a salt thereof.

2. The leave-on formulation according to claim 1, wherein the component (A) is a chain polyol having 3 or more carbon atoms.

3. The leave-on formulation according to claim 1 or 2, wherein the content of component (A) in the composition is 0.05% by mass or more and 30% by mass or less.

4. The leave-on formulation according to any one of claims 1 to 3, wherein the mass ratio (B / A) of component (B) to component (A) contained in the composition is 0.05 or more and 30 or less.

5. The leave-on formulation according to any one of claims 1 to 4, wherein the pH of the composition at 25°C is 3.5 or higher but less than 10.

6. The leave-on formulation according to any one of claims 1 to 5, wherein the content of the monoalcohol having 4 or less carbon atoms in the composition is 15% by mass or less.

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