Topical composition

Abstract

To provide a formulation which stably contains zinc and a mugwort extract.SOLUTION: A topical composition comprises a mugwort extract, and contains a citric acid, sodium citrate, and zinc so as to fulfill appropriate conditions.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to an external composition and the like. The contents of all documents described in this specification are incorporated herein by reference.

Background Art

[0002] As shown in Patent Document 1, when zinc gluconate, which is a kind of water-soluble zinc salt, and mugwort extract are used in combination in a hair-growing composition, cloudiness occurs. However, it is known that this can be suppressed by blending a diester of cyclohexanedicarboxylic acid and polyoxyethylene monoalkyl ether. However, this method cannot suppress the precipitation that occurs when mugwort extract and a water-soluble zinc salt are used in combination, so a solution is desired.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There was a problem that precipitates occurred over time in a lotion containing mugwort extract and a water-soluble zinc salt. For this reason, it was necessary to find a method in which no precipitate occurs even when mugwort extract and a water-soluble zinc salt are used in combination.

Means for Solving the Problems

[0005] The present inventor earnestly studied to stably blend mugwort extract and a water-soluble zinc salt. As a result, it was found that the generation of precipitates can be suppressed by blending sodium citrate, citric acid, and a water-soluble zinc salt under specific conditions. If these conditions are not satisfied, there is a risk of precipitation.

Effects of the Invention

[0006] By providing a method that does not generate precipitates even over time, mugwort extract and a water-soluble zinc salt can be stably formulated into an external composition.

[0007] This disclosure includes, for example, the subject matter described in the following items. Item 1. An external composition containing mugwort extract and a water-soluble zinc salt, further containing citric acids that satisfy the following conditions. Zinc content 0.1% by mass or less Sodium citrate / citric acid (mass ratio) 10 - 189 Citric acid equivalent value 0.4 - 7.2 Citric acid equivalent value / zinc content 7.5 - 112 Item 2. The external composition according to Item 1, wherein the water-soluble zinc salt is zinc gluconate.

Mode for Carrying Out the Invention

[0008] Hereinafter, embodiments according to the present invention will be described.

[0009] The external composition included in this disclosure contains citric acid, sodium citrate, mugwort extract, and zinc gluconate. This external composition may be referred to as "the external composition of this disclosure".

[0010] The content of the water-soluble zinc salt in the external composition is not particularly limited, but it is preferable that zinc is contained in the external composition at 0.5 to 0.1% by mass. More preferably, the water-soluble zinc salt is contained at 0.8 to 0.1% by mass.

[0011] It is preferable that citric acid is contained in the external composition at 0.05 to 0.5% by mass. More preferably, citric acid is contained in the external composition at 0.1 to 0.4% by mass.

[0012] Sodium citrate is preferably contained in the external composition in an amount of 0.05 to 0.5% by mass. More preferably, sodium citrate is contained in the external composition in an amount of 0.1 to 0.4% by mass.

[0013] The amount of zinc in the present invention refers to the mass% of zinc element in the external composition. The amount of zinc was calculated assuming that the atomic weight of zinc is 65.39 g / mol and the molecular weight of zinc gluconate is 455.685 g / mol.

[0014] The amount of zinc in the present invention is preferably 0.1% by mass or less in the external composition. More preferably, the amount of zinc is 0.06% by mass or less in the external composition. Even more preferably, the amount of zinc is 0.03% by mass or less in the external composition.

[0015] The value of citric acid conversion in the present invention is calculated by the following formula. In the present invention, the molecular weights of citric acid and sodium citrate were calculated assuming 192.124 g / mol and 258.06 g / mol, respectively. ([Molecular weight of citric acid] / [Molecular weight of Na citrate])×[Content mass (%) of Na citrate]+[Content mass (%) of citric acid] Citrates other than sodium citrate, such as potassium citrate, are not preferred.

[0016] The value of citric acid conversion in the present invention is preferably in the range of 0.4 to 7.2. More preferably, the value of citric acid conversion in the present invention is in the range of 0.45 to 7.0. Even more preferably, the value of citric acid conversion in the present invention is in the range of 0.50 to 6.5.

[0017] The “Na citrate / citric acid” in the present invention is calculated by the following formula. [Content mass (%) of Na citrate] / [Content mass (%) of citric acid]

[0018] The value of "sodium citrate / citric acid" in the present invention is preferably in the range of 10 to 189. More preferably, the value of "sodium citrate / citric acid" in the present invention is in the range of 15 to 150.

[0019] Regarding the "citric acid equivalent value / zinc amount" in the present invention, it is calculated by the following formula. [Citric acid equivalent value calculated in <0015>] / [Zinc content mass (%)]

[0020] The value of "citric acid equivalent value / zinc amount" in the present invention is preferably in the range of 7.5 to 112.

[0021] Although not particularly limited, examples of the form of the skin external composition of the present invention include ointments, creams, gels, lotions, emulsions, beauty essences, lotions, face packs, etc., and can be used as cosmetics, quasi-drugs, or pharmaceuticals.

[0022] In the skin external composition of the present invention, within a range that does not impair the effects of the present invention, known optional components that can generally be formulated in skin external compositions may be further formulated alone or in combination of two or more.

[0023] In the skin care composition of the present invention, in addition to the above components, if necessary, components usually used in skin care compositions of cosmetics and quasi-drugs can be appropriately formulated within a range that does not impair the effects of the present invention. For example, surfactants, polymer compounds, oils and fats, alcohols, moisturizers, antioxidants, ultraviolet absorbers, preservatives, chelating agents, amino acids, sugars, vitamins, animal and plant extracts, coloring agents, inorganic powders and organic powders such as powder agents, pH adjusters such as organic acids and inorganic acids, etc. can be appropriately formulated according to the use. Specific examples of the components that can be formulated are listed below.

[0024] ​Although there are no particular limitations on the surfactant, examples thereof include anionic surfactants; cationic surfactants; amphoteric surfactants such as imidazoline-based amphoteric surfactants and betaine-based surfactants; nonionic surfactants such as sorbitan-based surfactants, glycerin fatty acid esters, polyglycerin fatty acid esters, propylene glycol fatty acid esters, alkyl glycosides, Tween-based surfactants, polyoxyethylene glycerin fatty acid esters, polyoxyethylene polyglycerin fatty acid esters, polyoxyethylene propylene glycol fatty acid esters, polyoxyethylene hydrogenated castor oil derivatives, sucrose fatty acid esters, polyoxyethylene alkyl ethers, Pluronic type surfactants, and alkanolamides.

[0025] Although there are no particular limitations on the high molecular compound, polyethylene glycol having an average molecular weight of about several hundreds to 20,000 ; cellulose-based polymers; alginic acid-based polymers; starch-based polymers; acrylic-based polymers; non-natural polymers such as vinyl-based polymers, and plant-based polymers such as carrageenan, pectin, agar, starch, gum arabic, guar gum, and algocolloid, animal-based polymers such as collagen and its derivatives, casein, and gelatin, and natural polymers such as microbial-based polymers such as xanthan gum and gellan gum are exemplified.

[0026] Although there are no particular limitations on the oils and fats, examples thereof include vegetable oils; animal oils; hydrocarbon oils such as liquid paraffin, squalane, and petrolatum; silicones such as linear polysiloxanes, cyclic polysiloxanes, methyltrimethicone, silicone resins, and modified polysiloxanes; higher fatty acids such as lauric acid, stearic acid, and oleic acid; waxes such as beeswax, lanolin, and its derivatives; monoalkyl fatty acid esters; polyhydric alcohol fatty acid esters; and hydrogenated oils.

[0027] Examples of the alcohols include lower alcohols such as ethyl alcohol and butyl alcohol; higher alcohols such as lauryl alcohol, stearyl alcohol, behenyl alcohol, and batyl alcohol; polyhydric alcohols such as ethylene glycol, propylene glycol, 1,3-butylene glycol, and glycerin; polyhydric alcohol polymers such as dipropylene glycol, diglycerin, and polyglycerin; sugar alcohols such as sorbitol, maltitol, mannitol, and erythritol; and other alcohols such as lanolin alcohol, cholesterol, and phytosterol.

[0028] Examples of the humectants include polyhydric alcohols such as low molecular weight polyethylene glycol, propylene glycol, 1,3-butylene glycol, and glycerin; chondroitin sulfate; hyaluronic acid; sodium lactate; pyrrolidone carboxylate; collagens; and plant extracts.

Examples

[0029] Test examples and formulation examples are given below to further specifically describe this embodiment, but the present invention is not limited thereto. External compositions of Examples 1 and 2 were prepared according to the compositions and contents (mass %) shown in Table 1 below.

[0030]

Table 1

[0031] (Stability evaluation test) For the external compositions of Examples 1 and 2 shown in Table 1, stability tests were carried out at -5°C, 25°C, and 40°C. Each composition was left at each temperature for 3 months, and those without precipitation were evaluated as ○, those with slight precipitation were evaluated as △, and those with precipitation or other crystals were evaluated as ×.

[0032] As shown in Table 1, for Examples 1 and 2, no precipitation was observed even after 3 months at each temperature, and the results of the stability tests were good.

Claims

1. An external composition containing mugwort extract and a water-soluble zinc salt, further containing citric acids that satisfy the following conditions. Zinc content: 0.1% by mass or less Sodium citrate / citric acid (mass ratio): 10 - 189 Citric acid equivalent value: 0.4 - 7.2 Citric acid equivalent value / zinc content: 7.5 - 112

2. The external composition according to Claim 1, wherein the water-soluble zinc salt is zinc gluconate.

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