JP2022094517A - Emulsified composition for external use - Google Patents

Abstract

To provide an emulsified composition for external use that comprises urea and a salicylic acid-based anti-inflammatory agent and that can suppress phase separation and decomposition of urea due to storage.SOLUTION: An emulsified composition for external use comprises urea and a salicylic acid-based anti-inflammatory agent, as well as a sorbitan fatty acid ester and/or glycerin fatty acid ester. This emulsified composition for external use can suppress phase separation and decomposition of urea due to storage and exhibit high storage stability.SELECTED DRAWING: None

Description

The present invention relates to an external emulsified composition containing urea and a salicylic acid-based anti-inflammatory agent, which can suppress phase separation and urea decomposition by storage.

Urea has a water retention action by forming a hydrogen bond with water in the keratin and an action of removing or softening unnecessary keratin due to protein denaturation, and is used in an external composition. On the other hand, since urea is easily hydrolyzed in the external composition, it is necessary to stabilize the urea in the external composition containing urea. Therefore, various studies have been made on the formulation of an external composition capable of stabilizing urea. For example, Patent Document 1 discloses that urea can be stabilized by blending a neutral amino acid such as glycine in an external composition containing urea. Further, Patent Document 2 discloses that the external composition can be provided with excellent pharmaceutical stability by containing 10 to 25% by weight of urea and retinol or a derivative thereof.

On the other hand, salicylic acid, salicylic acid derivatives, and salicylic acid-based anti-inflammatory agents such as salts thereof are used in external compositions for anti-inflammatory and analgesic applications.

Further, the emulsified preparation is widely used in the field of external composition because it can contain an aqueous component and an oily component, can be used for various preparation formulations, and has an excellent usability when applied to the skin.

In recent years, consumer demand for improving the functionality of external compositions has increased, and in order to meet such consumer needs, it is desired to develop an external emulsified composition containing urea and a salicylic acid-based anti-inflammatory agent. ing.

Japanese Unexamined Patent Publication No. 7-97326 Japanese Unexamined Patent Publication No. 2008-31159

The present inventor has conducted various studies to develop an external emulsified composition containing urea and a salicylic acid-based anti-inflammatory agent, and found that the external emulsified composition containing urea and a salicylic acid-based anti-inflammatory agent is preserved. It was found that there was a problem in terms of storage stability due to phase separation and decomposition of urea.

Therefore, it is an object of the present invention to provide an external emulsified composition containing urea and a salicylic acid-based anti-inflammatory agent and capable of suppressing phase separation and decomposition of urea by storage.

As a result of diligent studies to solve the above problems, the present inventor has found that an external emulsified composition containing a sorbitan fatty acid ester and / or a glycerin fatty acid ester in addition to urea and a salicylic acid-based anti-inflammatory agent is phase-separated by storage. And it was found that the decomposition of urea can be suppressed and excellent storage stability can be provided. Furthermore, the present inventor has also found that the external emulsified composition has good elongation when applied around the nail and has an excellent softening effect on the keratin around the nail. The present invention has been completed by further studies based on such findings.

That is, the present invention provides the inventions of the following aspects.
Item 1. An external emulsified composition comprising (A) urea, (B) a salicylic acid-based anti-inflammatory agent, and (C) a sorbitan fatty acid ester and / or a glycerin fatty acid ester.
Item 2. Item 2. The external emulsified composition according to Item 1, which does not contain glycine.
Item 3. Item 2. The external emulsification composition according to Item 1 or 2, further comprising (D) at least one glycyrrhizic acid selected from the group consisting of glycyrrhizic acid, glycyrrhetinic acid, derivatives thereof, and salts thereof.
Item 4. Item 2. The external emulsified composition according to any one of Items 1 to 3, further comprising (E) a saturated fatty acid having 14 or more carbon atoms and / or a salt thereof.
Item 5. Item 6. The external emulsified composition according to any one of Items 1 to 4, which is used for softening the keratin around the nail.

According to the external emulsification composition of the present invention, although it contains urea and a salicylic acid-based anti-inflammatory agent, phase separation and decomposition of urea due to storage can be suppressed, and excellent storage stability can be provided. Further, the external emulsified composition of the present invention has good elongation when applied around the nail, has an excellent softening effect on the keratin around the nail, and can be suitably used for softening the keratin around the nail.

It is a photograph of the appearance of the external emulsified composition after storage.

1. 1. External emulsification composition

The external emulsified composition of the present invention is characterized by containing (A) urea, (B) a salicylic acid-based anti-inflammatory agent, and (C) a sorbitan fatty acid ester and / or a glycerin fatty acid ester. Hereinafter, the external emulsified composition of the present invention will be described in detail.

[(A) Urea]
The external emulsified composition of the present invention contains urea (sometimes referred to as component (A)). Urea is a known component known to have a water retention action in the keratin, an unnecessary keratin removal or softening action, and the like.

The content of the component (A) in the external emulsified composition of the present invention may be appropriately set according to the medicinal effect to be imparted, the intended use of the external emulsified composition, etc., and is, for example, 1 to 30% by weight, preferably 1 to 30% by weight. 5 to 25% by weight, more preferably 10 to 20% by weight.
[(B) Salicylic acid anti-inflammatory agent]
The external emulsified composition of the present invention contains a salicylic acid-based anti-inflammatory agent (sometimes referred to as a component (B)).

Specific examples of the salicylic acid-based anti-inflammatory agent include salicylic acid, salicylic acid derivatives, and salts thereof. Examples of the derivative of salicylic acid include acetylsalicylic acid (aspirin), salicylic acid (ethenzamid), sulfosalicylic acid, methyl salicylic acid, ethyl salicylic acid, glycol salicylate, ethylene glycol salicylate, dipropylene glycol salicylate, titanium salicylate, 2-ethylhexyl salicylate, and salicylic acid. Examples thereof include homomentyl and phenyl salicylate. Examples of salts of salicylic acid and its derivatives include alkali metal salts such as sodium and potassium; and alkaline earth metal salts such as magnesium. These salicylic acid-based anti-inflammatory agents may be used alone or in combination of two or more.

Among these salicylic acid-based anti-inflammatory agents, salicylic acid, salts of salicylic acid, ethyl salicylate, methyl salicylate, and more preferably salicylic acid can be mentioned.

The content of the component (B) in the external emulsified composition of the present invention may be appropriately set according to the medicinal effect to be imparted, the intended use of the external emulsified composition, etc., but for example, the total amount of the component (B) is 0. 0.01 to 1% by weight, preferably 0.05 to 0.5% by weight, and more preferably 0.1 to 0.5% by weight.

In the external emulsified composition of the present invention, the ratio of the component (A) to the component (B) is not particularly limited, but for example, the total amount of the component (B) is 0. Examples thereof include 01 to 300 parts by weight, preferably 0.05 to 100 parts by weight, and more preferably 0.1 to 50 parts by weight.

[(C) Sorbitan fatty acid ester and / or glycerin fatty acid ester]
The external emulsified composition of the present invention contains a sorbitan fatty acid ester and / or a glycerin fatty acid ester (sometimes referred to as a component (C)). In the prior art, when the component (A) and the component (B) coexist in the external emulsified composition, phase separation and decomposition of the component (A) occur due to storage, but the external emulsified composition of the present invention further causes sorbitan fatty acid. By containing an ester and / or a glycerin fatty acid ester, it is possible to suppress phase separation and decomposition of the component (A) due to storage. Further, in the external emulsification composition of the present invention, by containing the components (A) to (C), the elongation when applied around the nail is improved, and the keratin softening effect around the nail is excellent. be able to.

The sorbitan fatty acid ester is an ester of sorbitan and a fatty acid, and is a known nonionic surfactant. The number of fatty acids bound per molecule of the sorbitan fatty acid ester is not particularly limited, but is, for example, 1 to 4, preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. Can be mentioned. The carbon number of the fatty acid constituting the sorbitan fatty acid ester is not particularly limited, and examples thereof include 10 to 22, preferably 14 to 22, and more preferably 16 to 20. Specific examples of the sorbitan fatty acid ester include sorbitan monooleate, sorbitan monostearate, sorbitan sesquioleate, sorbitan sesquistearate, sorbitan coconut oil fatty acid, sorbitan monopalmitate, sorbitan tristearate, and sorbitan trioleate. Can be mentioned. Among these sorbitan fatty acid esters, sorbitan monostearate, sorbitan sesquistearate, sorbitan tristearate, and more preferably monostearate are preferable from the viewpoint of more effectively suppressing phase separation and urea decomposition during storage. Sorbitan acid can be mentioned.

The glycerin fatty acid ester is an ester of glycerin and a fatty acid, and is a known nonionic surfactant. Examples of the carbon number of the fatty acid constituting the glycerin fatty acid ester include 10 to 22, preferably 14 to 22, and more preferably 16 to 20. The number of fatty acids bound to one molecule of the glycerin fatty acid is not particularly limited, and examples thereof include 1 to 3, preferably 1 or 2, and more preferably 1. Specific examples of the glycerin fatty acid ester include glyceryl monomyristate, glyceryl monostearate, glyceryl monoisostearate, glyceryl monooleate, glyceryl dimyristate, glyceryl distearate, glyceryl diisostearate, and glyceryl dioleate. .. Among these glycerin fatty acid esters, glyceryl monostearate, glyceryl monomyristate, and glyceryl monoisostearate are preferable from the viewpoint of more effectively suppressing phase separation and urea decomposition during storage.

The content of the component (C) in the external emulsified composition of the present invention is, for example, 0.01 to 20% by weight, preferably 0.05 to 10% by weight, more preferably 0. 1 to 5% by weight is mentioned.

In the external emulsified composition of the present invention, the ratio of the component (A) to the component (C) is not particularly limited, but for example, the total amount of the component (C) is 0. Examples thereof include 01 to 300 parts by weight, preferably 0.05 to 100 parts by weight, and more preferably 0.1 to 50 parts by weight.

[glycine]
The external emulsified composition of the present invention may contain glycine, but preferably does not contain glycine. Conventionally, it is known that glycine has an action of stabilizing urea, but in the case of the external emulsified composition of the present invention, when glycine is not contained, phase separation by storage and decomposition of urea are more effective. It becomes possible to suppress it.

Moreover, one aspect of the external emulsification composition of the present invention is that it does not contain a neutral amino acid (an amino acid whose side chain does not contain an amino group or a carboxyl group).

[(D) Glycyrrhizic acid]
The external emulsified composition of the present invention is designated as at least one glycyrrhizic acid ((D) component) selected from the group consisting of glycyrrhizic acid, glycyrrhetinic acid, derivatives thereof, and salts thereof in addition to the above-mentioned components. May be included). By further containing the component (D) in the external composition of the present invention, the effect of suppressing phase separation and urea decomposition by storage is further improved, and the effect of stretching and softening the keratin around the nail when applied around the nail is obtained. It can be further improved.

Glycyrrhizic acid and glycyrrhetinic acid are known drugs known to have anti-inflammatory action, antiallergic action and the like.

The derivative of glycyrrhizic acid is not particularly limited as long as it is pharmaceutically acceptable, and examples thereof include methyl glycyrrhizinate and stearyl glycyrrhizinate. These derivatives of glycyrrhizic acid may be used alone or in combination of two or more.

The derivative of glycyrrhetinic acid is not particularly limited as long as it is pharmaceutically acceptable, and examples thereof include pyridoxine glycyrrhetinate, stearyl glycyrrhetinate, glyceryl glycyrrhetinate, and monoglucuronide glycyrrhetinate. These derivatives of glycyrrhetinic acid may be used alone or in combination of two or more.

The salt of glycyrrhizinic acid, glycyrrhetinic acid and / or a derivative thereof is not particularly limited as long as it is pharmaceutically acceptable, and examples thereof include alkali metal salts such as sodium salt and potassium salt; ammonium salts and the like. These salts may be used alone or in combination of two or more.

In the external emulsification composition of the present invention, as the component (D), one of glycyrrhizic acid, glycyrrhetinic acid, derivatives thereof, and salts thereof may be selected and used alone, or two or more thereof. May be used in combination.

Among the components (D), glycyrrhizinic acid and its above are preferable from the viewpoint of further improving the phase separation by storage and the effect of suppressing the decomposition of urea, and the effect of stretching around the nail and the effect of softening the keratin around the nail. Examples thereof include a salt, more preferably a salt of glycyrrhizinic acid, and even more preferably monoammonium glycyrrhizinate.

When the external emulsified composition of the present invention contains the component (D), the content thereof is not particularly limited, but for example, the total amount of the component (D) is 0.05 to 5% by weight, preferably 0.1. It is about 1% by weight, more preferably 0.3 to 0.5% by weight.

When the component (D) is contained in the external composition of the present invention, the ratio of the component (D) to the component (A) is not particularly limited, but for example, the component (D) is contained in 1 part by weight of the component (A). The total amount is 0.01 to 300 parts by weight, preferably 0.05 to 100 parts by weight, and more preferably 0.1 to 50 parts by weight.

[(E) Saturated fatty acids with 14 or more carbon atoms and / or salts thereof]
The external emulsified composition of the present invention may contain a saturated fatty acid having 14 or more carbon atoms and / or a salt thereof (sometimes referred to as a component (E)), if necessary. When the external emulsified composition of the present invention further contains the component (E), the phase separation due to storage can be remarkably suppressed, and the elongation when applied around the nail can be further improved.

Saturated fatty acids and / or salts thereof may have 14 or more carbon atoms, but from the viewpoint of more effectively suppressing phase separation due to storage and further improving elongation when applied around the nails. , Preferably 14 to 30 carbon atoms, more preferably 14 to 24 carbon atoms, still more preferably 14 to 22 carbon atoms, and particularly preferably 18 carbon atoms. Saturated fatty acids, more specifically, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoseric acid, cellotic acid, montanic acid, melicic acid; preferably myristic acid, palmitic acid, stearic acid, arachidic acid. , Bechenic acid, lignoseric acid: more preferably myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid; more preferably stealic acid.

Examples of the salt of saturated fatty acid having 14 or more carbon atoms include alkali metal salts such as sodium salt and potassium salt.

In the external composition of the present invention, as the component (E), one may be selected and used from among saturated fatty acids having 14 or more carbon atoms and salts thereof, or two or more thereof may be used in combination. good.

When the component (E) is contained in the external emulsified composition of the present invention, the content thereof is not particularly limited, but for example, the total amount of the component (E) is 0.01 to 10% by weight, preferably 0.1. 6% by weight, more preferably 1 to 6% by weight.

When the external emulsifying composition of the present invention contains the component (E), the ratio of the component (A) to the component (E) is not particularly limited, but for example, per 100 parts by weight of the total amount of the component (A), ( E) The total amount of the components is 0.1 to 1200 parts by weight, preferably 0.1 to 100 parts by weight, and more preferably 0.1 to 50 parts by weight.

[Multivalent alcohol]
The external emulsified composition of the present invention may contain a polyhydric alcohol, if necessary.

The polyhydric alcohol is not particularly limited as long as it is pharmaceutically acceptable, and examples thereof include 1,3-butylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, and glycerin. Among these polyhydric alcohols, glycerin is preferable. These polyhydric alcohols may be used alone or in combination of two or more.

When the external emulsified composition of the present invention contains a polyhydric alcohol, the content thereof is not particularly limited, but for example, the total amount of the polyhydric alcohol is 0.1 to 30% by weight, preferably 0.5 to 20%. By weight%, more preferably 1 to 10% by weight.

[Surfactants other than component (C)]
The external composition for skin of the present invention may contain a surfactant other than the above-mentioned component (C), if necessary.

Examples of the surfactant other than the component (C) include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants and the like other than the component (C). These surfactants may be used alone or in combination of two or more. Among these surfactants, a nonionic surfactant is preferable.

The nonionic surfactant (other than the component (C)) used in the present invention is not particularly limited as long as it is pharmaceutically acceptable, but for example, polyoxyethylene sorbitan fatty acid ester and polyoxyethylene alkyl. Examples thereof include ether and polyoxyethylene cured castor oil. Among these nonionic surfactants, preferably, polyoxyethylene sorbitan fatty acid ester and polyoxyethylene alkyl ether can be mentioned.

The average number of moles of ethylene oxide (EO) constituting the polyoxyethylene sorbitan fatty acid ester is not particularly limited, and examples thereof include 5 to 40 mol, preferably 10 to 30 mol, and more preferably 15 to 25 mol. Be done. The carbon number of the fatty acid constituting the polyoxyethylene sorbitan fatty acid ester is not particularly limited, and examples thereof include 10 to 22, preferably 14 to 22, and more preferably 16 to 20. Specific examples of the polyoxyethylene sorbitan fatty acid ester include polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, and polyoxyethylene sorbitan monostearate. Among these polyoxyethylene sorbitan fatty acid esters, monostearate polyoxyethylene sorbitan (polysorbate 60) having an average addition mole number of ethylene oxide (EO) of 20 can be mentioned.

The average number of moles of ethylene oxide (EO) constituting the polyoxyethylene alkyl ether is not particularly limited, and examples thereof include 5 to 40 mol, preferably 10 to 30 mol, and more preferably 15 to 25 mol. .. The number of carbon atoms of the alkyl group constituting the polyoxyethylene alkyl ether is not particularly limited, and examples thereof include 10 to 24 carbon atoms, preferably 14 to 24 carbon atoms, and more preferably 16 to 24 carbon atoms. Specific examples of the polyoxyethylene alkyl ether include polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, and polyoxyethylene araquil ether. Among these polyoxyethylene alkyl ethers, polyoxyethylene alkyl ethers are preferable.

When the external emulsified composition of the present invention contains a surfactant (other than the component (C)), the content thereof may be appropriately set according to the pharmaceutical form, usability, etc., but for example, the surfactant. The total amount of (other than the component (C)) is 0.5 to 20% by weight, preferably 1 to 15% by weight, and more preferably 1.5 to 10% by weight.

[Other ingredients]
In addition to the above-mentioned components, the external emulsified composition of the present invention may contain other commonly used additives, if necessary. Examples of such additives include oily bases other than the component (E), water, monohydric lower alcohols, pH regulators, buffers, solubilizers, preservatives, preservatives, antioxidants, and stabilizers. , Fragrances, coloring agents and the like. When these additives are contained in the external emulsification composition of the present invention, the content thereof may be appropriately set according to the type of the additive to be used and the like.

The external emulsified composition of the present invention may contain a pharmacological component in addition to the above-mentioned components. Examples of such pharmacological components include steroids, antihistamines, local anesthetics, anti-inflammatory agents (other than component (B)), moisturizers (other than component (A)), bactericides, antibacterial agents, antipruritic agents, and skin. Protective agents, blood circulation promoting ingredients, vitamins, mucopolysaccharides and the like can be mentioned. These pharmacological components may be used alone or in combination of two or more. When these pharmacological components are contained in the external composition of the present invention, the concentration thereof may be appropriately set according to the type of the pharmacological component used, the expected effect, and the like.

[Emulsification type / pharmaceutical form]
The emulsification type of the external emulsification composition of the present invention may be either an oil-in-water type or a water-in-oil type, and an oil-in-water type is preferable.

The pharmaceutical form of the external emulsified composition of the present invention is not particularly limited, and examples thereof include external pharmaceuticals such as creams, emulsions, lotions, liniments, and aerosols. Among these, a cream agent is preferably mentioned.

[Use]
The use of the external emulsified composition of the present invention is not particularly limited, but the external emulsified composition of the present invention has a keratin softening or removing action and a moisturizing action based on the component (A), and an anti-inflammatory action based on the component (B). Since it can exert its action, it is suitably used for applications such as softening or removing keratin, moisturizing, and anti-inflammatory. In particular, the external emulsifying composition of the present invention has good elongation when applied around the nail and has an excellent effect of softening the keratin around the nail, and is therefore suitably used for softening the keratin around the nail. ..

[Production method]
The external emulsified composition of the present invention can be produced according to a known method for formulating an emulsified preparation, depending on the emulsified type. For example, in the method for producing an external emulsified composition of the present invention, the components to be contained are divided into a water-soluble component and an oil-based component, and an aqueous phase containing the water-soluble component and an oil phase containing the oil-based component are prepared. There is a method of emulsifying according to a known method.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Test Example 1
An external emulsified composition (creamy oil-in-water emulsified preparation) having the compositions shown in Tables 1 to 3 was prepared. Specifically, first, surfactants (sorbitan monostearate, sorbitan sesquistearate, sorbitan tristearate, glyceryl monoisostearate, glyceryl monomyristate, glyceryl monostearate, polyoxyethylene hydrogenated castor oil 10, polysorbate). 60), fatty acid (stearic acid, myristic acid, palmitic acid, behenic acid, oleic acid, linoleic acid), hydrocarbon oil (white vaseline, liquid paraffin), cetostearyl alcohol, and polyoxyethylene / stearyl alcohol mixture in a predetermined amount. A composition for an oil phase was prepared by mixing and heating and dissolving at 80 ° C. Separately, a composition for an aqueous phase was prepared by mixing a predetermined amount of urea, salicylic acid, glycine, monoammonium glycyrrhizinate, triethanolamine and water. Next, the aqueous phase composition heated to 80 ° C. is gradually added to the oil phase composition heated to 80 ° C., mixed and emulsified, and the external emulsified composition (creamy oil-in-water mold) is performed. Emulsified preparation) was obtained. The external emulsified compositions immediately after production were all in an emulsified form in which phase separation did not occur.

For each of the obtained external emulsified compositions, the stability of the emulsified state, the stability of urea, and the elongation and keratin softening effect when applied around the nail were evaluated by the following methods.

<Stability in emulsified state>
16 g of each external emulsified composition immediately after preparation was filled in a 20 ml glass bottle and stored for 1 month under a light-shielded condition of 50 ° C. The appearance of each external emulsified composition after storage for 1 month was visually observed, and 15 points were "a state in which phase separation was not observed and the same emulsified state as immediately after preparation was maintained", and "phase separation was observed". The degree of stability of the emulsified state was scored between 1 and 15 points, with 1 point being "a state in which the emulsified state could not be stably maintained and was not uniform even when shaken." For reference, FIG. 1 shows the appearance of each external emulsified composition evaluated as 1 point and 15 points.

<Urea stability>
16 g of each external emulsified composition immediately after preparation was filled in a 20 ml glass bottle and stored for 2 months under a light-shielded condition of 50 ° C. The urea concentration in each external emulsified composition before and after storage for 2 months is quantified by HPLC, and the urea concentration before storage is set to 100%, and the residual rate (%) of urea after storage for 2 months is set to the first decimal place. The rounded value was calculated. The value of the residual rate (%) of urea after storage for 2 months was classified according to the following criteria.
・ Judgment criteria ◎: Urea residual rate is 98-100%
◯: Urea residual rate is 95 to 97%
Δ: Urea residual rate is 92 to 94%
×: Urea residual rate is 91% or less

<Elongation and keratin softening effect when applied around nails>
Ten subjects who were aware of the hardening of the stratum corneum around the nails were allowed to apply 0.1 g of each external emulsified composition around the nails once a day for one week, and around the nails at the time of the first application. The elongation and the softening effect of the keratin around the nail after 1 week of use were evaluated. The evaluation of elongation when applied around the nails is "good elongation", "somewhat good elongation", "neither", "somewhat poor elongation", and "poor elongation". The total number of subjects who evaluated "good elongation" or "relatively good elongation" was calculated as a score of elongation when applied around the nail. Regarding the softening effect of the keratin around the nail, there are five stages of "satisfied", "slightly satisfied", "neither", "slightly dissatisfied" and "dissatisfied" in terms of the softening effect of the keratin around the nail. The total number of subjects evaluated as "satisfied" or "slightly satisfied" was calculated as the score of the softening effect of the keratin around the nail.

The results are shown in Tables 1 to 3. In the external emulsification composition containing urea alone, phase separation did not occur due to storage and decomposition of urea was suppressed, but the elongation and softening effect of keratin when applied around the nails were insufficient. (Reference example 1). On the other hand, in the external emulsified composition containing urea and salicylic acid, phase separation due to storage occurs remarkably, decomposition of urea is also observed, and the elongation and softening effect of keratin when applied around the nail are insufficient. (Comparative Examples 1 and 2).

On the other hand, in the external emulsified composition containing sorbitan fatty acid ester and / or glycerin fatty acid ester together with urea and salicylic acid, phase separation and decomposition of urea due to storage can be sufficiently suppressed, and when applied around the nails. The elongation and softening effect of keratin were sufficiently improved (Examples 1 to 15). Furthermore, when glycine was not contained, the decomposition of urea due to storage could be remarkably suppressed (Examples 7 to 15). In addition, when monoammonium glycyrrhizinate was contained, the phase separation by storage and the effect of suppressing the decomposition of urea, and the effect of stretching and softening the keratin when applied around the nail were significantly improved (Examples 9 to 9). 15). Further, when the saturated fatty acid having 14 or more carbon atoms was further contained, the phase separation due to storage could be remarkably suppressed, and the elongation when applied around the nail was further improved (Example 11). ~ 15). Further, an external emulsified composition in which salicylic acid in each of the external emulsified compositions of Comparative Examples 1 and 2 was changed to ethyl salicylate or methyl salicylate was prepared, and the emulsified state, urea stability, and nail circumference were prepared by the same method as in Test Example 1. When the elongation and keratin softening effect when applied to were evaluated, the same degree of phase separation and urea decomposition as in Comparative Examples 1 and 2 corresponding to this occurred, and the elongation and keratin when applied around the nails The softening effect score was similar. On the other hand, each external emulsified composition in which salicylic acid in each external composition of Examples 1 to 15 was changed to ethyl salicylate or methyl salicylate was prepared, and the emulsified state, urea stability, and urea stability were prepared by the same method as in Test Example 1. When the elongation and the keratin softening effect when applied around the nail were evaluated, phase separation and the decomposition of urea could be suppressed to the same extent as in Examples 1 to 15 corresponding to this, and when applied around the nail. The scores of elongation and softening effect of keratin were similar.

Formulation Example An external emulsification composition (creamy oil-in-water emulsified preparation) having the composition shown in Table 4 was prepared. The emulsified state, the stability of urea, the elongation when applied around the nail, and the keratin softening effect were evaluated by the same method as in Test Example 1. The external emulsified compositions of Formulation Examples 1 to 7 were able to sufficiently suppress phase separation and urea decomposition during storage, and were also excellent in elongation and keratin softening effect when applied around the nail.

Claims (5)

An external emulsified composition comprising (A) urea, (B) a salicylic acid-based anti-inflammatory agent, and (C) a sorbitan fatty acid ester and / or a glycerin fatty acid ester. The external emulsified composition according to claim 1, which does not contain glycine. The external emulsification composition according to claim 1 or 2, further comprising (D) at least one glycyrrhizic acid selected from the group consisting of glycyrrhizic acid, glycyrrhetinic acid, derivatives thereof, and salts thereof. (E) The external emulsified composition according to any one of claims 1 to 3, further containing (E) a saturated fatty acid having 14 or more carbon atoms and / or a salt thereof. The external emulsified composition according to any one of claims 1 to 4, which is used for softening the keratin around the nail.

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