Non-wash-off skin external preparation composition

Abstract

The present application relates to a non-wash type skin external preparation composition, which contains: (A) one or more acids selected from the group consisting of lactic acid, pyruvic acid, and urocanic acid, or a salt thereof; and (B) a non-ionic surfactant having a lipophilic group with a carbon number of 12 and an HLB of 8.0 or more and 17.0 or less, and the content of component (A) is 0.02% by mass or more and 20.0% by mass or less, the content of component (B) is 0.006% by mass or more and 5.0% by mass or less, and the pH of the non-wash type skin external preparation composition is 3.5 or more and 5.0 or less.

Description

TECHNICAL FIELD

[0001] The present application relates to a composition for a skin external preparation which is a leave-on type. BACKGROUND

[0002] According to recent investigations, it is known that the infection route of bacteria or viruses in daily life of human is mainly contact infection. The contact infection is mainly caused by the contact of fingers to an infected person, a doorknob, a handle, tableware, toys, other daily goods, interior goods, and the like.

[0003] The industry is seeking a method for preventing the contact infection of bacteria or viruses caused by the contact behavior in daily life.

[0004] As a method for preventing the contact infection of bacteria or viruses via fingers, a method of applying an alcohol-based disinfectant or the like to the fingers to perform sterilization and disinfection is known. However, alcohol such as ethanol used as a sterilization or disinfection component has high volatility, and from the viewpoint of imparting sterilization and virucidal effects to the fingers, the persistence of the effects is insufficient.

[0005] Therefore, the industry is studying a method of imparting a defense function against bacteria or viruses to the fingers in advance. According to this method, an infection prevention effect against bacteria or viruses can be continuously obtained, and thus the contact infection can be prevented even in an environment where there is no place to wash hands such as a destination of an outing. In particular, the infection can be prevented even when repeatedly contacting a contacted object to which bacteria or viruses are attached, and is preferable in this point.

[0006] It is also known that an organic acid or a salt thereof is used as a component for achieving sterilization or virucidal.

[0007] For example, in Patent Literature 1 (Japanese Patent Laid-Open No. 2008-523064), as a method for inhibiting bacteria and viruses present on the skin surface of a mammal, a method is disclosed which includes contacting a compound or composition that can reduce the pH of the skin to about less than 4 with the skin for at least about 0.5 hours. As the above-mentioned compound or composition that can reduce the pH of the skin, a composition containing an organic acid such as a monocarboxylic acid, a polycarboxylic acid, or the like is exemplified.

[0008] In Patent Literature 2 (U.S. Patent No. 6034133), a method is disclosed in which, after being specified as having a cold due to a rhinovirus or before being exposed to a rhinovirus, a virucidal composition (hand cream) containing citric acid, malic acid, and a C1-6 alcohol is applied to the hands of a patient to kill the rhinovirus, thereby preventing the spread of a cold due to the rhinovirus.

[0009] It is also known that surfactants have antibacterial effects (Non-Patent Literature 1: WASHIO, A., Current Status and Trends of Antibacterial Surfactants, YUSHIKWAI, Vol. 29, No. 8, p536-542, 1980). It is described in Non-Patent Literature 1 that, among surfactants, cationic surfactants such as quaternary ammonium salts or amphoteric surfactants exhibit strong antibacterial properties, while anionic surfactants exhibit weak antibacterial properties, and polyethylene glycol-type nonionic surfactants exhibit no or extremely weak antibacterial properties. SUMMARY

[0010] The present application provides the following [1] and [2].

[0011] [1] A leave-on-type skin external preparation composition, comprising: (A) one or more acids selected from the group consisting of lactic acid, pyruvic acid, and urocanic acid, or a salt thereof; and (B) a nonionic surfactant having a lipophilic group with a carbon number of 12 and an HLB of 8.0 or more and 17.0 or less; and the content of component (A) is 0.02 mass% or more and 20.0 mass% or less, the content of component (B) is 0.006 mass% or more and 5.0 mass% or less, and the pH of the leave-on-type skin external preparation composition is 3.5 or more and 5.0 or less.

[0012] [2] A method for protecting skin from bacteria or viruses, comprising the step of applying the leave-on-type skin external preparation composition described in [1] above to the skin. DETAILED DESCRIPTION

[0013] [Leave-on-type skin external preparation composition]

[0014] The leave-on-type skin external preparation composition of the present application (hereinafter also referred to as "the composition of the present application") contains:

[0015] (A) one or more acids selected from the group consisting of lactic acid, pyruvic acid, and urocanic acid, or a salt thereof; and

[0016] (B) a nonionic surfactant having a lipophilic group with a carbon number of 12 and an HLB of 8.0 or more and 17.0 or less; and

[0017] the content of component (A) is 0.02 mass% or more and 20.0 mass% or less, the content of component (B) is 0.006 mass% or more and 5.0 mass% or less, and the pH of the leave-on-type skin external preparation composition is 3.5 or more and 5.0 or less.

[0018] The composition of the present application, by having the above-mentioned constitution, becomes a skin external preparation composition that has high bactericidal or virucidal activity, has less skin irritation, and is highly safe for the human body.

[0019] In Example 2 of Patent Literature 1, compositions 2A to 2C containing citric acid and malic acid are disclosed, and only the composition 2A having a pH of 2.3 shows antiviral activity against rhinovirus. In addition, the antiviral composition 2D containing citric acid and malic acid disclosed in Example 3 has a pH of 3.1. However, from the viewpoint of skin irritation, it is not preferable to apply a composition having a low pH to the skin.

[0020] The hand cream described in Patent Literature 2 contains citric acid, malic acid and a C1-6 alcohol as essential components, and the virucidal activity of a hand cream having a composition other than this is not disclosed. In addition, since the hand cream contains an alcohol component, there is a concern that skin irritation will occur.

[0021] The nonionic surfactant such as a polyethylene glycol type nonionic surfactant described in Non-Patent Literature 1 is a component that is usually used as an emulsifier for foods, cosmetics and the like, and although skin irritation is small even when it is contained in a leave-on skin external preparation composition, the bactericidal and virucidal effects produced by it alone are weak.

[0022] In view of the above, the object of the present inventors is to provide a leave-on skin external preparation composition that uses an organic acid under mild conditions having a pH of 3.5 or higher, and uses a nonionic surfactant that has low concerns of skin irritation even when it is contained in a leave-on skin external preparation composition, and further shows a high bactericidal or virucidal activity even without using an alcohol component.

[0023] That is, the present application relates to a leave-on skin external preparation composition that has a high bactericidal or virucidal activity, has low skin irritation, and has high safety to the human body.

[0024] The present inventors have found that a composition containing a specific amount of one or more acids selected from lactic acid, pyruvic acid and urocanic acid or a salt thereof, and a nonionic surfactant having a lipophilic group having a carbon number of 12 and an HLB within a specific range, and having a pH of 3.5 or higher, which is relatively high, has low skin irritation and high safety to the human body even when it is used as a leave-on skin external preparation, and can improve the bactericidal or virucidal activity.

[0025] Here, the one or more acids selected from lactic acid, pyruvic acid and urocanic acid are organic acids that are originally present on human skin, and when used as a composition having a pH of 3.5 or higher, have low skin irritation and high safety to the human body, but have weak bactericidal or virucidal effects by themselves. In addition, the nonionic surfactant, as described above, has weak bactericidal or virucidal effects by itself.

[0026] However, the present inventors and others believe that a nonionic surfactant having a lipophilic group with a carbon atom number of 12 and an HLB within a specific range penetrates into the cell membrane of a pathogenic bacteria or virus and increases the fluidity of the cell membrane, and the aforementioned organic acid component becomes easily absorbed into the pathogenic bacteria or virus. Thus, by using the aforementioned organic acid component in combination with the nonionic surfactant, the organic acid component is efficiently absorbed into the pathogenic bacteria or virus, and even a composition having a pH of 3.5 or higher can improve the effect of inactivating or killing the pathogenic bacteria or virus.

[0027] According to the present application, it is possible to provide a leave-on skin external preparation composition which has high bactericidal or virucidal activity, has little skin irritation, and has high safety for the human body.

[0028] In the present specification, the "leave-on skin external preparation composition" refers to a skin external preparation composition which is used without being removed by washing with water or the like after being applied to the skin.

[0029] The composition of the present application can impart a bactericidal or virucidal effect to the skin surface by leaving the components (A) and (B) as bactericidal or virucidal components on the skin surface. From the viewpoint of obtaining this effect, the composition of the present application is used by being left on the skin surface without being removed by washing with water or the like after being applied to the skin by rubbing or the like.

[0030] From the viewpoint of preventing contact infection by pathogenic bacteria or viruses, the composition of the present application is more preferably a leave-on skin external preparation composition for the fingers.

[0031] In the present specification, the "bactericidal or virucidal activity" refers to the bactericidal or virucidal activity possessed by the composition itself. For example, the bactericidal activity against Escherichia coli and the virucidal activity against coronavirus can be specifically evaluated by the methods described in the examples. The activity against other pathogenic bacteria and viruses can be evaluated by referring to technical common sense.

[0032] In the present specification, "imparting a bactericidal or virucidal effect to the skin surface" includes the concept of imparting the following effects: (1) a bactericidal or virucidal effect exhibited against pathogenic bacteria or viruses adhering to the skin surface after the composition of the present application is applied to the skin surface; (2) a bactericidal or virucidal effect exhibited by applying the composition to pathogenic bacteria or viruses adhering to the skin; (3) an effect of adjusting the skin so that it cannot be used as a medium by pathogenic bacteria or viruses; (4) an effect of protecting the skin from pathogenic bacteria or viruses and maintaining hygiene; (5) an effect of preventing the spread and contact infection of pathogenic bacteria or viruses via the skin; and (6) an effect of improving the infection defense power of the skin against pathogenic bacteria or viruses, and the like.

[0033] In addition, in the present specification, if the pH of the composition at 25°C is 3.5 or higher, the skin irritation can be inhibited.

[0034] As the pathogenic bacteria or virus which becomes the object of the bactericidal or virucidal activity of the composition of the present application, any pathogenic bacteria or virus which is inactivated or killed by contact with an acid is considered to be acceptable, and there is no particular limitation, and for example, microorganisms described in the Guidelines for Infection Control in Child Care Facilities of the Ministry of Health, Labour and Welfare of Japan can be applied.

[0035] Specifically, as the pathogenic bacteria, for example, Bacillus anthracis, Mycobacterium tuberculosis, Streptococcus hemolyticus, Staphylococcus aureus, Streptococcus pneumoniae, and the like as gram-positive bacteria, or Francisella tularensis, Yersinia pestis, Brucella spp., Glanders, Vibrio cholerae, Salmonella bacteria, dyscentery bacillus, Enterohemorrhagic E. coli, Bordetella pertussis, and the like as gram-negative bacteria can be exemplified. In addition, as the virus, for example, arenaviruses, Ebola virus, Variola virus, Nairovirus, Marburg virus, coronavirus, monkeypox virus, betacoronavirus, influenza virus, RS (respiratory syncytial) virus, herpesvirus, mumps virus, varicella-zoster virus, rubella virus, measles virus, and the like as enveloped viruses, and Enterovirus, adenovirus, Coxsackievirus, Norovirus, Rotavirus, and the like as non-enveloped viruses can be exemplified.

[0036] In addition, in the present embodiment, the bactericidal and virucidal activities were evaluated using E. coli and coronavirus as examples, but the pathogenic bacteria or virus which becomes the object of the present application is not limited thereto.

[0037] The reason why the composition of the present application exerts the above effects is not clear, but is considered as follows.

[0038] The present inventors have found that lactic acid, pyruvic acid, and urocanic acid, which are components (A), are present on the skin of humans, particularly on the fingers, and function to kill bacteria, viruses, and the like. Therefore, it is believed that a skin external preparation composition containing components (A) can be produced as a composition having a high bactericidal or virucidal activity, low skin irritation, and high human safety.

[0039] With regard to the above-mentioned bactericidal or virucidal activity, it is known that the bactericidal or virucidal activity of a composition containing components (A) is higher as the pH of the composition is lower. For example, lactic acid as a component (A) can exist in an acid form (CH3CH(OH)COOH) and a dissociated form (CH3CH(OH)COO - ) in an aqueous solution, but the acid form, which has no charge, is easily absorbed into bacteria or viruses, and thus it is believed that the acid form exhibits a higher bactericidal or virucidal activity. The ratio of the acid form to the dissociated form of lactic acid depends on the pH, and if the pH exceeds 5, the proportion of the acid form decreases, and the proportion of lactic acid existing in the acid form with respect to the total amount of lactic acid is, for example, less than 5 mol%. The composition of the present application exhibits a higher bactericidal or virucidal activity by having a pH of 5.0 or lower.

[0040] On the other hand, in the case of using components (A), there is also a concern that a composition in a low-pH region causes skin irritation.

[0041] In view of this, the present inventors have conducted studies, and as a result, it has been found that by using a specific amount of components (A) and components (B) as a specific nonionic surfactant, respectively, it is possible to improve the bactericidal or virucidal activity even in a composition having a pH in a higher range of 3.5 or higher.

[0042] As described above, nonionic surfactants such as polyethylene glycol-type nonionic surfactants have weak bactericidal or virucidal effects even when they are included in a leave-on skin external preparation composition. However, components (B) of nonionic surfactants having a lipophilic group with a carbon atom number of 12 and an HLB in a specific range have an effect of penetrating into the cell membrane of bacteria or viruses and improving the fluidity of the cell membrane, and along with this, components (A) become easily absorbed into bacteria or viruses. Therefore, it is believed that by using components (A) and components (B) in combination, components (A) are efficiently absorbed into bacteria or viruses, and the effect of inactivating or killing bacteria or viruses is improved.

[0043] It is believed that by the above-mentioned mechanism of action, a skin external preparation composition having a pH of 3.5 or higher, low skin irritation, and high bactericidal or virucidal activity can be obtained.

[0044] <Components (A)>

[0045] The component (A) for the composition of the present application is one or more acids selected from the group consisting of lactic acid, pyruvic acid, and uric acid, or a salt thereof. The component (A) functions as a bactericidal or virucidal component.

[0046] As the salts of lactic acid, pyruvic acid, and uric acid, there can be mentioned alkali metal salts such as potassium salts, sodium salts, and the like; alkaline earth metal salts such as calcium salts, magnesium salts, and the like; amine salts; ammonium salts, and the like. Of these, from the viewpoint of improving the bactericidal or virucidal activity, and the viewpoint of 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 uric 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 further preferred.

[0047] From the viewpoint of improving the bactericidal or virucidal activity, as the component (A), lactic acid or a salt thereof is preferred, one or more selected from the group consisting of lactic acid, potassium lactate, sodium lactate, and calcium lactate is more preferred, and a composition containing lactic acid is further preferred.

[0048] In the case where the component (A) contains lactic acid, from the viewpoint of improving the bactericidal or virucidal activity, the content of lactic acid or a salt thereof in the total amount of the component (A) is preferably 80% by mass or more, more preferably 90% by mass or more, and most preferably 100% by mass.

[0049] From the viewpoint of improving the bactericidal or virucidal activity, the content of the component (A) in the composition of the present application is 0.02% by mass or more, preferably 0.05% by mass or more, more preferably 0.1% by mass or more, further preferably 0.3% by mass or more, further more preferably 0.5% by mass or more. From the viewpoint of suppressing skin irritation, on the other hand, it is 20.0% by mass or less, preferably 15.0% by mass or less, more preferably 10.0% by mass or less, further preferably 5.0% by mass or less, further more preferably 3.0% by mass or less, and further more preferably 2.0% by mass or less. Furthermore, the content of the component (A) in the composition of the present application is 0.02% by mass or more and 20.0% by mass or less, preferably 0.05% by mass or more and 15.0% by mass or less, more preferably 0.1% by mass or more and 10.0% by mass or less, further preferably 0.3% by mass or more and 5.0% by mass or less, further more preferably 0.3% by mass or more and 3.0% by mass or less, and further more preferably 0.5% by mass or more and 2.0% by mass or less.

[0050] In the present specification, in the case where the component (A) contains a salt, the "content of the component (A)" means the amount converted to an acid.

[0051] The content of component (A) in the acid form in the composition of the present application is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, from the viewpoint of improving the bactericidal or viricidal activity. In addition, it is preferably 15% by mass or less, more preferably 10% by mass or less, further preferably 7% by mass or less, further more preferably 1% by mass or less, from the viewpoint of suppressing skin irritation. Furthermore, the content of component (A) in the acid form in the composition of the present application is preferably 0.01% by mass or more and 15% by mass or less, more preferably 0.01% by mass or more and 10% by mass or less, further preferably 0.01% by mass or more and 7% by mass or less, further more preferably 0.1% by mass or more and 1% by mass or less.

[0052] The molar ratio [acid form / (acid form + dissociated form)] of component (A) in the acid form to the total of component (A) in the acid form and component (A) in the dissociated form in the composition of the present application is preferably 0.068 or more, more preferably 0.12 or more, from the viewpoint of improving the bactericidal or viricidal activity. In addition, it is preferably 0.7 or less, more preferably 0.5 or less, from the viewpoint of suppressing skin irritation. Furthermore, the above-mentioned molar ratio [acid form / (acid form + dissociated form)] in the composition is preferably 0.068 or more and 0.7 or less, more preferably 0.12 or more and 0.5 or less.

[0053] The above-mentioned molar ratio can be calculated by the method described in the Examples, for example.

[0054] In the present specification, "component (A) in the acid form in the composition" means the component of component (A) that exists in the composition as lactic acid, pyruvic acid and urocanic acid, and "component (A) in the dissociated form in the composition" means the component of component (A) that exists in the composition as lactic acid ion, pyruvic acid ion and urocanic acid ion.

[0055] <Component (B)>

[0056] Component (B) used in the composition of the present application is a nonionic surfactant having a lipophilic group with a carbon number of 12 and an HLB (Hydrophilic-Lypophilic Balance) of 8.0 or more and 17.0 or less. It is considered that the composition of the present application, by containing component (A) and component (B), by the synergistic effect thereof, component (A) as a bactericidal or viricidal component is efficiently absorbed into a bacterium or a virus, and a high bactericidal or viricidal activity can be obtained.

[0057] As the lipophilic group having 12 carbon atoms in component (B), a monohydric alcohol residue having 12 carbon atoms or a fatty acid residue having 12 carbon atoms can be exemplified. From the viewpoint of improving the bactericidal or virucidal activity and the viewpoint of easy availability, the lipophilic group having 12 carbon atoms is preferably a group having a straight-chain aliphatic group, and the straight-chain aliphatic group is more preferably a straight-chain saturated aliphatic group.

[0058] More specifically, as the lipophilic group having 12 carbon atoms in component (B), from the viewpoint of improving the bactericidal or virucidal activity and the viewpoint of easy availability, it is preferable to be selected from one or more of the groups represented by R 11 -O-, R 12 -COO-, and R 12 -CONH-, and more preferably to be selected from one or more of the groups represented by R 11 -O-, and R 12 -COO-, and further preferably to be R 11 -O-. Here, R 11 is an aliphatic group having 12 carbon atoms, and R 12 is an aliphatic group having 11 carbon atoms.

[0059] From the viewpoint of improving the bactericidal or virucidal activity, the aliphatic group in R 11 and R 12 is preferably a straight-chain aliphatic group, and more preferably a straight-chain saturated aliphatic group.

[0060] Component (B) can have only one lipophilic group having 12 carbon atoms, or can have two or more thereof. From the viewpoint of improving the bactericidal or virucidal activity, component (B) is preferably a nonionic surfactant having only one lipophilic group having 12 carbon atoms as a main component. Here, the "main component" means that it is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more, and can be 100% by mass.

[0061] As a specific example of component (B), polyoxyethylene lauryl ether, sucrose laurate, polyoxyethylene laurate, polyglycerol lauryl ether, polyglyceryl laurate, lauryl glucoside, polyoxyethylene lauryl amine, polyoxyethylene sorbitan laurate, polyoxyethylene sorbitol laurate, and the like can be exemplified, and one or two or more of these can be used. Among them, from the viewpoint of improving the bactericidal or virucidal activity, component (B) is preferably one or more selected from polyoxyethylene lauryl ether, sucrose laurate, polyoxyethylene laurate, polyglycerol lauryl ether, polyglyceryl laurate, lauryl glucoside, and polyoxyethylene lauryl amine.

[0062] In the above, from the viewpoint of improving the solubility and stability of the composition, the average addition mole number of oxyethylene groups (hereinafter referred to as "EO average addition mole number") in polyoxyethylene lauryl ether, polyoxyethylene lauryl ester, polyoxyethylene lauryl amine, polyoxyethylene sorbitan lauryl ester, and polyoxyethylene sorbitol lauryl ester is preferably 2 or more, more preferably 3 or more, from the viewpoint of improving the bactericidal or virucidal activity and obtaining a desired HLB value, and is preferably 20 or less, more preferably 15 or less, further preferably 10 or less. Also, the EO average addition mole number is preferably 2 or more and 20 or less, more preferably 3 or more and 20 or less, further preferably 3 or more and 15 or less, further more preferably 3 or more and 10 or less. In addition, the EO average addition mole number is a number average value.

[0063] In the above, as the lauryl ester in sucrose lauryl ester, polyoxyethylene lauryl ester, polyoxyethylene sorbitan lauryl ester, and polyoxyethylene sorbitol lauryl ester, in addition to a monoester, a diester, a triester, and the like can be exemplified, and a mixture of a monoester and a polyester can also be used. From the viewpoint of improving the bactericidal or virucidal activity and obtaining a desired HLB value, the above lauryl ester is preferably a monoester as a main component. Here, the "main component" means that it is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, in the total amount of the above lauryl ester.

[0064] As component (B), one or two or more nonionic surfactants can be used. In the above, from the viewpoint of improving the bactericidal or virucidal activity, component (B) is more preferably one or more selected from polyoxyethylene lauryl ether, sucrose lauryl ester, and polyoxyethylene lauryl ester, further preferably one or more selected from polyoxyethylene lauryl ether and sucrose lauryl ester, further more preferably polyoxyethylene lauryl ether. It is preferable that the EO average addition mole number in polyoxyethylene lauryl ether and polyoxyethylene lauryl ester be within the above range (preferably 2 or more and 20 or less, more preferably 3 or more and 15 or less, further preferably 3 or more and 10 or less), and that sucrose lauryl ester and polyoxyethylene lauryl ester have a monoester as a main component.

[0065] (HLB)

[0066] From the viewpoint of improving the solubility and stability of the composition, the HLB of component (B) of the composition used in the present application is 8.0 or more. In addition, from the viewpoint of improving the bactericidal or virucidal activity, the HLB is 17.0 or less, preferably 16.5 or less, more preferably 16.0 or less, further preferably 15.5 or less, further more preferably 14.0 or less, further more preferably 13.5 or less.

[0067] HLB is a value indicating the ratio of the molecular weight of the hydrophilic group portion to the total molecular weight of the surfactant, and is calculated by the Griffin formula.

[0068] In addition, the component (B) of the present application refers to a nonionic surfactant having a lipophilic group with a carbon number of 12 and an HLB within the above range, and the content of the component (B) contained in the composition refers to the total amount of the nonionic surfactant having a lipophilic group with a carbon number of 12 and satisfying the above HLB range.

[0069] From the viewpoint of improving the bactericidal or virucidal activity, the content of the component (B) in the composition of the present application is 0.006% by mass or more, preferably 0.01% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, further more preferably 0.2% by mass or more. From the viewpoint of suppressing skin irritation and improving the use feeling, it is 5.0% by mass or less, preferably 3.0% by mass or less, further preferably 2.5% by mass or less, further more preferably 2.0% by mass or less, further more preferably 1.5% by mass or less. Furthermore, the content of the component (B) in the composition of the present application is 0.006% by mass or more and 5.0% by mass or less, preferably 0.01% by mass or more and 5.0% by mass or less, more preferably 0.05% by mass or more and 5.0% by mass or less, further preferably 0.1% by mass or more and 5.0% by mass or less, further more preferably 0.1% by mass or more and 3.0% by mass or less, further more preferably 0.2% by mass or more and 2.5% by mass or less, further more preferably 0.2% by mass or more and 2.0% by mass or less, further more preferably 0.2% by mass or more and 1.5% by mass or less.

[0070] The total content of the component (A) and the component (B) in the composition of the present application is preferably 0.026% by mass or more, more preferably 0.15% by mass or more, further preferably 0.2% by mass or more, further more preferably 0.35% by mass or more, further more preferably 0.4% by mass or more, and more further preferably 1.0% by mass or more, from the viewpoint of improving the bactericidal or virucidal activity. In addition, it is preferably 15.0% by mass or less, more preferably 10.0% by mass or less, further preferably 5.0% by mass or less, and further more preferably 3.0% by mass or less, from the viewpoint of suppressing skin irritation. Furthermore, the total content of the component (A) and the component (B) in the composition of the present application is preferably 0.026% by mass or more and 15.0% by mass or less, more preferably 0.15% by mass or more and 15.0% by mass or less, further preferably 0.2% by mass or more and 15.0% by mass or less, further more preferably 0.2% by mass or more and 10.0% by mass or less, further more preferably 0.35% by mass or more and 5.0% by mass or less, more further preferably 0.4% by mass or more and 5.0% by mass or less, and more further more preferably 1.0% by mass or more and 3.0% by mass or less.

[0071] The composition of the present application can also contain a surfactant other than the component (B). As the surfactant other than the component (B), anionic surfactants, cationic surfactants (except for quaternary ammonium salts), amphoteric surfactants (except for alkyl diaminomethyl glycine hydrochlorides and alkyl polyaminomethyl glycine), and nonionic surfactants other than the component (B) can be exemplified. As the anionic surfactants, alkyl phosphate salts, polyoxyethylene alkyl ether sulfate salts, and the like can be exemplified, and as the amphoteric surfactants, lauroamphoacetate, lauryl betaine, and the like can be exemplified.

[0072] Among them, the ratio of the component (B) in the surfactants in the composition of the present application is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more, and can also be 100% by mass, from the viewpoint of the bactericidal or virucidal activity.

[0073] The total content of the surfactants containing the component (B) in the composition of the present application is preferably 5.0% by mass or less, and more preferably 3.0% by mass or less, from the viewpoint of suppressing skin irritation.

[0074] In addition, the total content of the anionic surfactants and the cationic surfactants in the composition of the present application is preferably 1.0% by mass or less, more preferably 0.5% by mass or less, and further preferably 0.1% by mass or less, from the viewpoint of suppressing skin irritation.

[0075] Further, from the viewpoint of suppressing skin irritation, the content of the above-mentioned amphoteric surfactant is preferably 3.0% by mass or less, more preferably 1.0% by mass or less, and further preferably 0.5% by mass or less.

[0076] Further, in the composition of the present application, the content of the nonionic surfactant containing component (B) is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, and further preferably 1.5% by mass or less. Also, from the viewpoint of bactericidal or virucidal activity, the ratio of component (B) in the nonionic surfactant is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more, and can also be 100% by mass.

[0077] From the viewpoint of improving bactericidal or virucidal activity, the mass ratio of component (B) to component (A) (component (B) / component (A)) in the composition of the present application is preferably 0.005 or more, more preferably 0.1 or more, further preferably 0.1 or more, further more preferably 0.2 or more, and on the other hand, is preferably 20 or less, more preferably 10 or less, further preferably 5 or less, and further more preferably 2 or less. Also, the above-mentioned mass ratio (component (B) / component (A)) in the composition of the present application is preferably 0.005 or more and 20 or less, more preferably 0.1 or more and 20 or less, further preferably 0.1 or more and 20 or less, further more preferably 0.2 or more and 10 or less, further more preferably 0.2 or more and 5 or less, and further more preferably 0.2 or more and 2 or less.

[0078] From the viewpoint of dissolving component (A) and component (B), and the viewpoint of easy application to the skin surface, the composition of the present application preferably further contains water. The content of water in the composition of the present application is preferably 10% by mass or more, more preferably 30% by mass or more, further preferably 50% by mass or more, and further more preferably 70% by mass or more, and on the other hand, is preferably 99.8% by mass or less, and more preferably 99% by mass or less. Also, the content of water in the composition of the present application is preferably 10% by mass or more and 99.8% by mass or less, more preferably 30% by mass or more and 99.8% by mass or less, further preferably 50% by mass or more and 99.8% by mass or less, and more preferably 70% by mass or more and 99% by mass or less.

[0079] From the viewpoint of obtaining the effects of the present application, the total content of the component (A), the component (B), and water in the composition of the present application is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, further more preferably 90% by mass or more, further more preferably 95% by mass or more, and can also be 100% by mass.

[0080] The composition of the present application can also contain other components as needed in addition to the above components, such as an acid or a salt thereof other than the component (A) (malic acid or adipic acid), a tackifier (polysaccharide or polymer, etc.), a pH adjuster (citric acid or sodium hydroxide, etc.), an ultraviolet absorber (titanium oxide or zinc oxide, etc.), an antioxidant (ascorbic acid or vitamin E, etc.), a preservative (methyl paraben or benzoic acid, etc.), an antiperspirant (zinc p-hydroxybenzenesulfonate or aluminum chloride hydrate, etc.), a fragrance (eucalyptus or geraniol, etc.), a moisturizer (polyhydric alcohol or natural oil, etc.), a touch adjuster (silicone or higher oil, etc.), an anti-inflammatory agent (glycyrrhizic acid, etc.), and the like.

[0081] In the case where the composition of the present application contains the above polyhydric alcohol, the content of the polyhydric alcohol in the composition is preferably 20% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, and further more preferably 3% by mass or less, from the viewpoint of improving the use feeling of the composition.

[0082] From the viewpoint that the composition of the present application is a composition in which the component (A) is used as a bactericidal or virucidal component, the bactericidal or virucidal activity is exhibited even if ethanol is not formulated. From the above viewpoint and the viewpoint of suppressing skin irritation, the content of ethanol in the composition is preferably 70% by mass or less, more preferably 50% by mass or less, further more preferably 30% by mass or less, further more preferably 10% by mass or less, further more preferably 3% by mass or less, further more preferably 1% by mass or less, further more preferably 0.07% by mass or less, further more preferably 0.05% by mass or less, further more preferably 0.03% by mass or less, further more preferably less than 0.01% by mass, and most preferably substantially 0% by mass.

[0083] From the viewpoint of suppressing skin irritation and improving the use feeling, the ratio of the total content of the polyhydric alcohol and ethanol in the composition of the present application to the content of water [(polyhydric alcohol + ethanol) / water] is preferably 2 or less, more preferably 1 or less, further preferably 0.5 or less, and further more preferably 0.1 or less, in terms of mass ratio.

[0084] From the viewpoint that the composition of the present application is a composition in which component (A) is used as a bactericidal or virucidal component, even if the following bactericides, such as benzalkonium chloride, benzethonium chloride and other quaternary ammonium salts; alkyl-diaminoethylglycine hydrochloride, alkylpolyaminoethylglycine and other amphoteric surfactants; chlorhexidine gluconate and other biguanides; sodium hypochlorite; glutaraldehyde, o-phthalaldehyde, formalin and other aldehydes; povidone-iodine; iodine tincture; phenol; cresol and soap solution; peroxoacetic acid; hydrogen peroxide; and the like, are not formulated, the composition exhibits bactericidal or virucidal activity. From the above viewpoint and the viewpoint of suppressing skin irritation, the content of the bactericide in the composition is preferably 15% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less, further preferably 3% by mass or less, further more preferably 1% by mass or less, further still more preferably 0.08% by mass or less, yet further preferably 0.07% by mass or less, further still more preferably 0.05% by mass or less, yet further more preferably 0.03% by mass or less, yet further more preferably less than 0.01% by mass, and most preferably substantially 0% by mass. On the other hand, in the case where the above bactericide is formulated, from the viewpoint of improving the bactericidal or virucidal activity, the content of the bactericide in the composition is preferably 0.01% by mass or more, further preferably 0.05% by mass or more.

[0085] In addition, from the viewpoint of suppressing skin irritation, the mass ratio of the above bactericide to component (A) (bactericide / component (A)) is preferably 0.1 or less, more preferably 0.05 or less, further preferably 0.03 or less, further more preferably 0.01 or less, and most preferably substantially 0. On the other hand, in the case where the above bactericide is formulated, from the viewpoint of improving the bactericidal or virucidal activity, the mass ratio of the above bactericide to component (A) (bactericide / component (A)) is preferably 0.01 or more, more preferably 0.05 or more.

[0086] In addition, in the present specification, an agent that is the above bactericide and also functions as a surfactant is defined as a bactericide.

[0087] From the viewpoint of using the composition of the present application as a composition in which component (A) is used as a bactericidal or virucidal component, even if an organic acid or a salt thereof other than component (A) is not formulated, a bactericidal or virucidal activity can be exhibited. From the above viewpoint and the viewpoint of suppressing skin irritation, the content of the acid or the salt other than component (A) in the composition is preferably 15% by mass or less, more preferably 10% by mass or less, further more preferably 5% by mass or less, further more preferably 3% by mass or less, further more preferably 1% by mass or less, further more preferably 0.5% by mass or less, more further preferably less than 0.5% by mass, further more preferably less than 0.1% by mass, most preferably substantially 0% by mass.

[0088] From the viewpoint of suppressing skin irritation, the content of succinic acid or a salt thereof among the organic acids or salts other than component (A) in the composition of the present application is preferably less than 1% by mass, further more preferably 0.7% by mass or less, further more preferably less than 0.5% by mass, most preferably substantially 0% by mass.

[0089] <PH>

[0090] From the viewpoint of suppressing skin irritation, the pH of the composition of the present application is 3.5 or more, preferably 3.7 or more. In addition, from the viewpoint of improving the bactericidal or virucidal activity, it is 5.0 or less, preferably 4.5 or less. The pH of the composition of the present application is specifically in the range of 3.5 or more and 5.0 or less, preferably 3.7 or more and 4.5 or less.

[0091] The above pH is a value at 25°C, and specifically, can be measured by the method described in the Examples.

[0092] The form of the composition of the present application is not particularly limited, and for example, can be a solid, a liquid, a gel, or a cream. From the viewpoint of easy application to the skin, a gel or a cream is preferred. The composition can be in the form of an emulsified composition, and as the emulsified composition, either an oil-in-water type emulsified composition or a water-in-oil type emulsified composition can be used.

[0093] The composition of the present application is a leave-on skin external preparation composition, and the dosage form of the preparation is not particularly limited. As the dosage form of the composition of the present application, for example, a stick-shaped preparation having a solid composition; a roll-on preparation or a spray preparation filled with a liquid composition; a preparation in which a liquid, a gel, or a cream composition is filled in a bottle, a tube, a dispenser-type container, or the like; a sheet product in which the composition is impregnated; and the like can be exemplified.

[0094] From the viewpoint of preventing contact infection by bacteria or viruses, the composition of the present application is preferably a skin external preparation composition for fingers. As a product form thereof, a finger sanitizer, a hand cream cosmetic, and the like can be exemplified.

[0095] [Defense method]

[0096] The present application also provides a method for protecting skin from bacteria or viruses, which comprises a step of applying the leave-on skin external preparation composition of the present application to the skin.

[0097] According to the method of the present application, it is possible to protect the skin from bacteria or viruses in a method with high skin irritation-inhibiting property and high human safety. The bacteria or viruses against which the method of the present application is directed are the same as described above.

[0098] The method of applying the above composition to the skin can be appropriately selected depending on the dosage form of the composition, the site of application, and the like, and, for example, the composition can be applied by spreading it on the skin surface or spraying it on the skin surface, or the like.

[0099] In the method of the present application, it is preferable that the above composition is applied to the skin and then the composition is left on the skin surface without washing it off with water or the like. The reason for this is that, by using the composition as a leave-on preparation and leaving the component (A) as a bactericidal or virucidal component on the skin surface, it is possible to impart a bactericidal or virucidal effect to the skin surface.

[0100] In this step, the amount of the above composition to be applied is not particularly limited as long as it is an amount that imparts a bactericidal or virucidal effect to the skin surface.

[0101] From the viewpoint of imparting a higher bactericidal or virucidal effect, in this step, the amount of the component (A) in the acid form on the skin surface to which the above composition is applied is preferably 1.5 μg or more, more preferably 1.7 μg or more, and even more preferably 2 μg or more per 1 cm2. 2 The skin preferably becomes an amount of 1.5 μg or more, more preferably 1.7 μg or more, and even more preferably 2 μg or more. In addition, from the viewpoint of inhibiting skin irritation, it is preferable that the skin becomes an amount of 200 μg or less, more preferably 100 μg or less, and even more preferably 50 μg or less. Furthermore, the amount of the component (A) in the acid form on the skin surface to which the above composition is applied is preferably 1.5 μg or more, more preferably 1.7 μg or more, and even more preferably 2 μg or more per 1 cm2. 2 The skin becomes an amount of 1.5 μg or more and 200 μg or less, more preferably 1.7 μg or more and 100 μg or less, and even more preferably 2 μg or more and 50 μg or less.

[0102] In addition, the "amount of component (A) in the acid form on the skin surface to which the composition is applied" means the total amount of component (A) in the acid form derived from the composition and component (A) in the acid form originally present on the skin surface at the point of time when the composition is applied.

[0103] The above composition can be applied to the skin after the skin is washed with water, soap, body soap, hand soap, etc. in advance, or can be applied to the skin without washing. The skin after washing is in a state where the component such as lactic acid originally present on the skin is washed away and the defense against bacteria or viruses present in the outside environment is reduced, and thus it is more preferable to apply the above composition to the skin after washing to carry out the method of the present application.

[0104] [Examples]

[0105] Hereinafter, the present application will be described by examples, but the present application is not limited by the scope of the examples. In the present examples, various measurements and evaluations were carried out by the following methods.

[0106] (pH value)

[0107] The pH value of the composition was measured at 25°C by using an electrode 6367-10D (manufactured by HORIBA, Ltd.).

[0108] (molar ratio of component (A) [acid form / (acid form + dissociated form)])

[0109] The above molar ratio of component (A) in the composition was calculated by the following formula. In addition, the acid form is denoted as "HA", and the dissociated form is denoted as "A - ".

[0110] pH = pKa + log(A - / HA)

[0111] log(A - / HA) = pH - pKa

[0112]

[0113] A - / HA = 10 (pH - pKa)

[0114]

[0115] A - = 10 (pH - pKa) x HA

[0116] According to the above, the molar ratio [acid form / (acid form + dissociated form)] is

[0117]

[0118] HA / (HA + A - ​​​) = HA / (HA + 10(pH - pKa) x HA)

[0119]

[0120] = 1 / (1 + 10(pH - pKa))

[0121] Here, in the case where lactic acid is used as the component (A) (pKa = 3.86),

[0122] Molar ratio [lactic acid / (lactic acid + lactic acid ion)] = 1 / (1 + 10 ＾ (x - 3.86))

[0123] (x represents the pH value of the composition or the pH value of the skin surface)

[0124] In addition, in the case where the component (A) contains a plurality of components, the calculation method defined in the present application is as follows. The pH value of the composition is measured according to the above method, and the pKa of each of the plurality of components is substituted into the above calculation formula, whereby the molar ratio [acid type / (acid type + dissociated type)] of each component is obtained. Then, the molar ratios [acid type / (acid type + dissociated type)] of each of the components are added, whereby the molar ratio [acid type / (acid type + dissociated type)] of the component (A) in the case where a plurality of components (A) is used can be obtained.

[0125] [Assessment 1: Evaluation of bactericidal property of the composition]

[0126] (Preparation of bacterial solution)

[0127] The bactericidal property evaluation uses a bacterial solution of Escherichia coli prepared by the following method.

[0128] As the Escherichia coli, NBRC3301 strain was used. The bacteria were cultured in LB liquid medium, and after recovering the bacterial bodies by centrifugation, they were adjusted to OD600 = 10 using pure water.

[0129] (Bactericidal activity of the composition)

[0130] 200 μL of the composition prepared in each of the examples and comparative examples was heated to 30°C using a heating block, and then 2 μL of the bacterial solution was mixed using a vortex mixer, and left to stand on the heating block at 30°C for 60 seconds. Thereafter, 15 μL of the mixture was transferred to 1500 μL of LP-PBS, and ice-bath cooling was performed, whereby the reaction was stopped (the effect of the composition prepared in each of the examples and comparative examples on the bacterial solution).

[0131] ​Then, the number of surviving bacteria was measured by the following method using a Bio Microplate Reader "HiTS" (manufactured by Scinics Corporation) to confirm the amount of reduction in the number of bacteria (number of surviving bacteria / initial number of living bacteria). The number of living bacteria in the bacterial solution was measured by measuring the absorbance (turbidity) at a wavelength of 600 nm over time in a Bio Microplate Reader "HiTS" at 37°C to produce a growth curve. At the same time, a bacterial solution having a known number of living bacteria was subjected to a graded dilution, and the same culture and growth curve production were performed to produce a calibration curve of the time to reach a fixed turbidity and the number of living bacteria. From the relationship between the time required for each sample to reach a fixed turbidity and the calibration curve, the number of surviving bacteria in the bacterial solution after the reaction was stopped was estimated, and the amount of reduction in the number of bacteria was confirmed.

[0132] Regarding the degree of reduction in the number of bacteria, the -log value of the above amount of reduction in the number of bacteria (log reduction value) was taken, and is shown in Table 1 (evaluation results a). The higher the value of the "log reduction value" for E. coli, the higher the bactericidal activity.

[0133] On the other hand, a composition in which component (A) was removed from each of the compositions of Examples 1 to 26 and Comparative Examples 1 to 7, 9 to 10 described in Tables 1 to 4 (i.e., component (A) was not added) was prepared, and the pH value was adjusted to the same value as that of the above-mentioned composition using an aqueous hydrochloric acid solution having a concentration of 1 mol / L, and the bactericidal activity was evaluated by the same method as above (evaluation results b).

[0134] Further, the difference (a-b) between the evaluation results a and b was calculated, and is shown in Tables 1 to 4. The larger the value of a-b, the higher the synergistic effect on the bactericidal activity brought about by the combination of component (A) and component (B), and it is suggested that the effect of promoting the absorption of component (A) into the bacterial body brought about by the use of component (B) is high.

[0135] [Evaluation 2: Evaluation of the virus-killing activity of the composition]

[0136] (Preparation of the virus solution)

[0137] After the HCT-8 cells (ATCC CCL-244) were infected with human coronavirus OC43 (ATCC VR-1558) and proliferated in a tissue culture flask, the cell culture supernatant was purified by centrifugal separation to prepare a virus solution having a virus titer of 10 7.9 TCID 50 / mL.

[0138] (Virus-killing activity of the composition)

[0139] To the test tube into which 45 μL of each composition was dispensed, 5 μL of the above virus solution was added, and immediately thereafter, mixed for 15 seconds using a vortex mixer. After standing at room temperature, the time point 3 minutes after the addition of the virus solution was set as reaction solution 1. To this, 950 μL of SCDLP solution (manufactured by Nippon Shinyaku Co., Ltd.) was added, and mixed for 10 seconds using a vortex mixer (reaction solution 2). The reaction was stopped by ice-bath cooling of the reaction solution 2. The ice-bath cooled reaction solution was diluted 10-fold in RPMI medium (manufactured by Sigma Aldrich) to which 2% of inactivated horse serum and 50 mg / L of gentamicin were added, and inoculated into the above HCT-8 cells. After incubation for 4 days at 33°C in a 5% CO2 incubator, the infected cells were confirmed by the following antibody staining method, and the virus infectivity value (TCID 50 / mL) was calculated.

[0140] With respect to the virucidal activity, the -log value (log reduction value) of the above virus infectivity value (TCID 50 / mL) with respect to the theoretical value 10 5.59 TCID 50 / mL (virus initial infectivity value 10 7.9 TCID 50 / mL at the time point of reaction solution 1, and 1 / 20 at the time point of reaction solution 2) after the reaction was taken, and is shown in Tables 1 to 4. The higher the value of the "log reduction value", the higher the virucidal activity.

[0141] (antibody staining method)

[0142] After inoculation of the virus, the cells after incubation for 4 days were fixed using methanol, and washed with phosphate buffered saline (PBS), and blocked with 0.5% bovine serum albumin (BSA) for 2 hours. After washing again with PBS, a primary antibody (Anti-Coronavirus Group Antigen Antibody, nucleoprotein of OC-43, clone 542-7D, manufactured by Merck) and a secondary antibody (HRP-conjugated goat anti mouse IgG+IgM (H+L), manufactured by Jackson immuno research) which specifically bind to the coronavirus were allowed to react for 2 hours, respectively. Then, the virus was stained using DEPDA coloring solution (40 mM citric acid buffer containing 2 mM 4-chloronaphthol, 2 mM N, N-diethyl-p-phenylenediamine sulfate, 0.01% hydrogen peroxide solution), and the presence or absence of infection of the cells with the virus was determined based on the presence or absence of blue coloration as an index.

[0143] Examples 1 to 26, Comparative Examples 1 to 10 (Preparation and evaluation of leave-on finger external preparation compositions)

[0144] With respect to Examples 1 to 26, Comparative Examples 1 to 7, 9 to 10, each component was mixed in the amounts shown in Tables 1 to 4 at room temperature, and then, using an aqueous sodium hydroxide solution having a concentration of 1 mol / L as a pH adjuster, the pH was adjusted to the values shown in the respective tables, to prepare leave-on finger external preparation compositions. The amounts shown in Tables 1 to 4 are effective component amounts (mass %) of each component.

[0145] Using the obtained compositions, various evaluations were performed by the above-described methods. In Comparative Example 8, only water (purified water) was used for the evaluation. The results are shown in Tables 1 to 4. The details of components *1 to *16 shown in Tables 1 to 4 are shown in Table 5.

[0146] In addition, in the compositions of Examples 1 to 26, Comparative Examples 1 to 7, 9 to 10, the molar ratio of lactic acid [acid type / (acid type + dissociated type)] and the content of the acid type of lactic acid in the composition were as shown in the tables.

[0147] [Table 1]

[0148] Table 1

[0149]

[0150] **: shows "-" where evaluation was not performed

[0151] [Table 2] Table 2

[0152]

[0153] [Table 3] Table 3

[0154]

[0155] [Table 4]

[0156] Table 4

[0157]

[0158] **: shows "-" where evaluation was not performed

[0159] [Table 5]

[0160] Table 5

[0161]

[0162] *2 to 9, 11 to 16: the numerical value in parentheses in the component name indicates the average addition molar number of EO.

[0163] *10: In sucrose laurate, the content of monoester is about 80 mass%, and the content of other polyesters is about 20 mass%.

[0164] As is apparent from Tables 1 to 4, the bactericidal activity of the composition of the present embodiment is higher than that of the composition of the comparative example (evaluation result a of evaluation 1). In addition, the composition of the present embodiment has a higher synergistic effect of the components (A) and (B) because the value of the difference (a-b) between the evaluation results a and b is larger than that of the composition of the comparative example.

[0165] Similarly, it is found that the composition of the present embodiment has a significantly improved virucidal activity compared to the comparative example 8 (evaluation 2).

[0166] As the composition of the present embodiment, the formulations shown in Table 6 can be prepared by conventional methods, respectively.

[0167] [Table 6]

[0168] Table 6

[0169]

[0170] The components described in Table 6 are as follows.

[0171] Lactic acid: Lactic acid (effective amount: 90%) manufactured by FUJIFILM and Meiji Seika Kaisha, Ltd.

[0172] Succinic acid: Succinic acid manufactured by FUJIFILM and Meiji Seika Kaisha, Ltd.

[0173] Polyoxyethylene (6) lauryl ether: Emulgen 108 manufactured by Kao Corporation, HLB 12.1, average addition mole number of EO 6

[0174] Polyoxyethylene (9) lauryl ether: Emulgen 109P manufactured by Kao Corporation, HLB 13.6, average addition mole number of EO 9

[0175] Sodium hydroxide: NaOH (sodium hydroxide aqueous solution) 48% manufactured by Kanto Chemical Co., Inc. was used by adjusting it to be a 1 mol / L aqueous solution of sodium hydroxide.

[0176] [Industrial applicability]

[0177] According to the present embodiment, a composition for skin external use of the leave-on type having high bactericidal or virucidal activity, low skin irritation, and high safety for the human body can be provided.

Claims

1. A no-rinse topical skin agent composition, wherein, contain: (A) Lactic acid; and (B) One or more nonionic surfactants selected from polyoxyethylene lauryl ether, polyoxyethylene (12) monolaurate, and sucrose laurate, with an average addition molar number of oxyethylene vinyl groups of 3 to 15. Furthermore, the content of component (A) is 0.02% by mass or more and 20.0% by mass or less, the content of component (B) is 0.006% by mass or more and 5.0% by mass or less, and the pH value of this no-rinse topical skin agent composition is 3.5 or more and 5.0 or less. The content of the bactericide is less than 0.01% by mass.

2. The no-rinse topical skin composition as described in claim 1, wherein, The component (B) is one or more polyoxyethylene lauryl ethers selected from those with an average addition molar number of oxyethylene of 3 to 12.

3. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The HLB value of the component (B) is above 8.0 and below 15.

5.

4. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The content of component (B) in the composition is less than 2.0% by mass.

5. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The composition contains a nonionic surfactant comprising component (B) at a content of 3.0% by mass or less.

6. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The proportion of component (B) in the nonionic surfactant of the composition is 70% by mass or more.

7. The no-rinse topical skin composition as described in claim 1 or 2, wherein, As the mass ratio of component (B) to component (A) in the composition, component (B) / component (A) is 0.005 or more and 20 or less.

8. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The composition further contains water.

9. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The ethanol content in the composition is less than 10% by mass.

10. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The bactericide content in the composition is 0 by mass.

11. The no-rinse topical skin composition as described in claim 1 or 2, wherein, As the mass ratio of the bactericide to the component (A), the bactericide / component (A) ratio is 0.1 or less.

12. The no-rinse topical skin composition as described in claim 1 or 2, wherein, The content of the acid or its salt other than component (A) in the composition is less than 15% by mass.

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