JP7449692B2 - Oil-based external composition - Google Patents

Description

The present invention relates to an oil-based external composition. More specifically, the present invention relates to an oil-based external composition that has improved dispersion stability, properties, and feel when used.

Oil-based external compositions are one type of external compositions, and contain an oily base material as a main component. Oil-based external compositions have high coating film adhesion, and the effects of the ingredients in them are long lasting.

In general, in external compositions, the transdermal absorption (distribution to the stratum corneum) of a drug is determined by the "compatibility between the base and the skin" (the ease with which the base blends into the skin) and the "compatibility between the base and the skin". It is known that the affinity between the drug and the drug (the ease with which the drug dissolves in the base) has a significant effect (Non-Patent Document 1), and the formulation of external compositions should be formulated with these balances in mind. is designed. For example, when formulating a fat-soluble drug, using an oil-based base improves transdermal absorption based on the base's affinity with the skin, and using a water-soluble base improves transdermal absorption based on the base's affinity with the skin. It is said to improve transdermal absorption based on the affinity between the drug and the drug.

Regarding oil-based external compositions, various formulations are being considered, taking into account not only the transdermal absorption of the above-mentioned drug, but also the stability of the drug in the formulation. For example, as an oil-based external preparation such as a lip balm that has high stability in the active ingredient formulation and has an excellent feeling of use, a) at least one water-soluble or fat-soluble active ingredient, b) fatty acid dextrin, hydroxystearic acid, etc. An oil-based external preparation (Patent Document 1) has been proposed, which is characterized by containing at least one member selected from the group consisting of: and c) an oil-based base.

Supervised by Michiteru Otani, “Coloring medicine knowledge vol.1”, [online], Maruho Co., Ltd., [searched on December 10, 2020], Internet <URL: https://www.maruho.co.jp /medical/pharmacist/infostore/vol01/05.html〉

Japanese Patent Application Publication No. 2003-128521

Tocopherol and its derivatives (hereinafter collectively referred to as tocopherols) are incorporated into oil-based external compositions containing an aqueous solvent as fat-soluble active ingredients, but they have the property of stably maintaining the dispersion system. (Dispersion stability) has not been studied. Even in the oil-based external preparation of Patent Document 1, the dispersion stability when tocopherols are actually blended has not been studied.

The present inventor faced the problem that when tocopherols were blended into an oil-based external composition containing an aqueous solvent, separation of the oil phase occurred and dispersion stability decreased. Therefore, when we tried increasing the amount of solid oily base, we found that the dispersion stability tended to be improved, but this time, the feeling of use was impaired due to excessive stickiness and oil film feeling. On the other hand, when a small amount of dextrin fatty acid ester, which is an oil-based gelling agent, is added, the effect of improving dispersion stability is only slight, and the viscosity of the oil-based topical composition is drastically reduced, causing problems with its properties. Ta. As described above, oil-based external compositions containing tocopherols and an aqueous solvent have a problem in that improved dispersion stability, properties, and feeling of use are not compatible with each other.

Therefore, an object of the present invention is to provide an oil-based external composition containing tocopherols and an aqueous solvent that has improved dispersion stability and has excellent properties and usability.

As a result of extensive studies, the present inventor has determined that in an oil-based external composition containing tocopherols and an aqueous solvent, beeswax, which is a solid oil, is used as the oil base, and a predetermined amount of dextrin fatty acid ester is blended with the beeswax. It has been found that by doing so, the dispersion stability is significantly improved, and the properties and usability are not impaired. The present invention was completed through further studies based on this knowledge.

That is, the present invention provides the following aspects of the invention.
Item 1. (A) tocopherol and/or a derivative thereof, (B) an oily base, (C) a dextrin fatty acid ester, and (D) an aqueous solvent, the (B) component contains (B1) solid oil, and the An oil-based external composition in which component (B1) contains (b1) beeswax, and the content of component (C) is 0.15 to 0.37 parts by weight per 1 part by weight of component (b1).
Item 2. Item 2. The oil-based external composition according to item 1, wherein the content of the component (C) is 0.5 to 1.8% by weight.
Item 3. Item 3. The oil-based external composition according to item 1 or 2, wherein the content of the component (C) is 2.5 to 9 parts by weight per 1 part by weight of the component (A).
Item 4. Item 4. The oil-based external composition according to any one of Items 1 to 3, wherein the component (B) contains (B2) a semi-solid oil and/or (B3) a liquid oil.
Item 5. Item 4. The oil-based external composition according to Item 4, when containing the component (B3), the content of the component (C) is 0.019 to 0.077 parts by weight per 1 part by weight of the component (B3). .
Item 6. Item 5. The oil-based external composition according to item 4 or 5, when the component (B3) is contained, the component (B3) is 28 to 33 parts by weight based on 100 parts by weight of the component (B).
Section 7. Item 7. The oil-based external composition according to any one of Items 1 to 6, wherein the content of the component (D) is 2 to 25% by weight.
Section 8. (A) contains tocopherol and/or its derivative, (B) an oily base, and (D) an aqueous solvent, the (B) component contains (B1) solid oil, and the (B1) component contains (b1). ) An oil-based external composition containing beeswax, in which (C) dextrin fatty acid ester is blended in an amount of 0.15 to 0.37 parts by weight per 1 part by weight of component (b1). Method for improving dispersion stability.

According to the present invention, although it is an oil-based external composition containing tocopherols and an aqueous solvent, it is possible to formulate a pharmaceutical composition with improved dispersion stability and excellent properties and usability.

1. Oil-based external composition The oil-based external composition of the present invention comprises (A) tocopherol and/or its derivative (hereinafter also referred to as "(A) component"), (B) an oil-based base (hereinafter referred to as "(B) component"). ), (C) dextrin fatty acid ester (hereinafter also referred to as "component (C)"), and (D) an aqueous solvent (hereinafter also referred to as "component (D)"), The (B) component contains (B1) solid oil (hereinafter also referred to as "(B1) component"), and the (B1) component contains (b1) beeswax (hereinafter also referred to as "(b1) component"). The content of the component (C) is 0.15 to 0.37 parts by weight per 1 part by weight of the component (b1). The oil-based external composition of the present invention will be described in detail below.

(A) Tocopherol and/or its derivative The oil-based external composition of the present invention contains tocopherol and/or its derivative (hereinafter also referred to as tocopherols) as component (A). When tocopherols are blended into an oil-based external composition containing an aqueous solvent, they destabilize the dispersibility of the oil-based external composition, but the oil-based external composition of the present invention can improve dispersion stability. .

Tocopherol is a well-known ingredient also known as vitamin E. The tocopherol used in the present invention may be either d-form or dl-form, and may have any of α, β, γ, and δ structures. Specifically, the tocopherol used in the present invention includes d-α-tocopherol, d-β-tocopherol, d-γ-tocopherol, d-δ-tocopherol, l-α-tocopherol, l-β-tocopherol, Examples include l-γ-tocopherol, l-δ-tocopherol, and mixtures thereof such as dl-α-tocopherol, dl-β-tocopherol, dl-γ-tocopherol, and dl-δ-tocopherol.

A tocopherol derivative is a component that has the same skeleton as tocopherol and is obtained by adding a substituent to tocopherol.

Like tocopherol, the tocopherol derivative used in the present invention may be either the d-form or the dl-form, and may have any of the α, β, γ, and δ structures.

The type of tocopherol derivative is not particularly limited as long as it is pharmaceutically acceptable, but examples include esters of tocopherol and organic acids. Specific examples of the ester of tocopherol and an organic acid include tocopherol acetate, tocopherol nicotinate, tocopherol succinate, tocopherol linolenic acid ester, and the like. These tocopherol derivatives may be used alone or in combination of two or more.

In the oil-based external composition of the present invention, as component (A), one type may be selected from tocopherol and tocopherol derivatives, or two or more types may be used in combination.

Among these components (A), tocopherol derivatives are preferred, and tocopherol acetate is more preferred.

In the oil-based external composition of the present invention, the content of component (A) is not particularly limited, but is, for example, 0.01 to 5% by weight, preferably 0.08 to 3% by weight, more preferably 0.1% by weight. -1% by weight, more preferably 0.1-0.3% by weight.

(B) Oily base The oily external composition of the present invention contains an oily base as the (B) component.

The oily bases include (B1) solid oil (hereinafter also referred to as "(B1) component"), (B2) semi-solid oil (hereinafter also referred to as "(B2) component"), and (B3). ) liquid oil (hereinafter also referred to as "component (B3)"). The oil-based external composition of the present invention includes component (B1) as component (B). In the oil-based external composition of the present invention, the (B) component may be either the (B2) component or the (B3) component together with the (B1) component, or the (B2) component and the (B3) component. Both components may be used. In the oil-based external composition of the present invention, it is preferable that the component (B) contains both the component (B2) and the component (B3) together with the component (B1).

The solid oil of component (B1) is an oil that maintains a solid form at 25°C. In the present invention, component (B1) includes (b1) beeswax. Component (b1) includes purified beeswax (for example, plain beeswax listed in the Japanese Pharmacopoeia) and unrefined beeswax (for example, beeswax listed in the Japanese Pharmacopoeia). These beeswax may be used alone or in combination of two or more. In the present invention, the component (b1) is preferably purified beeswax (white beeswax).

In the present invention, component (B1) can contain solid oil other than component (b1) (b2) (hereinafter also referred to as "component (b2)"). The component (b2) may be any solid oil normally used in cosmetics, external medicines, etc. other than the component (b1), such as petroleum waxes such as microcrystalline wax; carnauba wax, candelilla wax. , vegetable waxes such as rice wax and wood wax; animal waxes such as spermaceti wax; synthetic waxes such as silicone wax and polyethylene wax; fatty acids, higher alcohols, and derivatives thereof. Among these solid oils, petroleum waxes are preferred, and microcrystalline waxes are more preferred. These solid oils may be used alone or in combination of two or more.

The semi-solid oil of component (B2) is an oil that maintains a semi-solid (viscous and freely deformable) form at 25°C. Semi-solid oils used in the present invention may be those normally used in cosmetics, external medicines, etc., such as petrolatum, pasty hydrocarbons such as gelled hydrocarbons; lanolin, dimer acid esters, dimer acid esters, etc. Examples include diol derivatives, cholesterol fatty acid esters, phytosterol fatty acid esters, polyglycerin fatty acid esters, pentaerythritol fatty acid esters, and the like. These semi-solid oils may be used alone or in combination of two or more. Among these semi-solid oils, pasty hydrocarbons are preferred, and petrolatum and gelled hydrocarbons are more preferred.

The liquid oil of component (B3) is an oil that maintains a liquid form at 25°C. The liquid oil used in the present invention may be one that is normally used in cosmetics, external medicines, etc., such as vegetable oils such as avocado oil, camellia oil, macadamia nut oil, olive oil, and jojoba oil; oleic acid, isostearin, etc. Fatty acids such as acids; cetyl ethylhexanoate, ethylhexyl palmitate, octyldodecyl myristate, neopentyl glycol diethylhexanoate, glyceryl tri-2-ethylhexanoate, octyldodecyl oleate, isopropyl myristate, glyceryl triisostearate, Jibara Ester oils such as glyceryl methoxycinnamic acid-monoethylhexanoate; silicone oils such as dimethylpolysiloxane, methylhydrodienepolysiloxane, methylphenylpolysiloxane, and octamethylcyclotetrasiloxane; liquid hydrocarbons such as liquid paraffin, squalene, squalane, etc. Examples include oil. These liquid oils may be used alone or in combination of two or more. Among these liquid oils, liquid hydrocarbon oils are preferred, and liquid paraffin is more preferred.

Since the present invention is an oil-based external composition, component (B) is included as a main component. That is, in the oil-based external composition of the present invention, component (B) is contained in an amount of more than 50% by weight. Furthermore, from the viewpoint of further enhancing the effects of the present invention, the blending amount of component (B) is preferably 70% by weight or more, more preferably 73% by weight or more, still more preferably 76% by weight or more, and even more preferably 79% by weight. % or more, particularly preferably 79.4% by weight or more. The upper limit of the content range of component (E) is not particularly limited, but for example, 90% by weight or less, preferably 85% by weight or less, more preferably 83% by weight or less, still more preferably 80% by weight or less, even more preferably 79.6% by weight or less.

The blending amount of component (B1) in the oil-based external composition of the present invention is, for example, 5 to 25% by weight, preferably 10 to 23% by weight, more preferably 16 to 19% by weight, and even more preferably 18 to 19% by weight. can be mentioned.

Further, the content of component (b1) in the oil-based external composition of the present invention is not particularly limited as long as the content ratio with component (C) is within a predetermined range, but for example, 2 to 10% by weight, preferably 4 to 8% by weight, more preferably 4.3 to 8.5% by weight, still more preferably 4.5 to 6% by weight.

The ratio of the content of component (b1) per 100 parts by weight of component (B1) is determined based on the above content of each component, but is preferably 5 to 40 parts by weight, preferably 8 to 38 parts by weight, or more. It is preferably 15 to 34 parts by weight, more preferably 20 to 32 parts by weight, even more preferably 25 to 32 parts by weight, and particularly preferably 28 to 32 parts by weight.

Further, the ratio of the content of component (B1) per 100 parts by weight of component (B) is determined based on the above content of each component, but is preferably 15 to 30 parts by weight, more preferably 20 to 25 parts by weight. parts, more preferably 23.4 to 24.5 parts by weight, even more preferably 23.5 to 24.2 parts by weight, particularly preferably 23.9 to 24.2 parts by weight.

When component (B2) is included as component (B), the amount of component (B2) in the oil-based external composition of the present invention is, for example, 25 to 50% by weight, preferably 30 to 45% by weight, more preferably 35% by weight. -42% by weight, more preferably 37-39% by weight.

Further, when component (B2) is included as component (B), the ratio of the content of component (B2) per 100 parts by weight of component (B) is determined based on the above content of each component; 55 parts by weight, preferably 38 to 53 parts by weight, more preferably 45 to 50 parts by weight, even more preferably 47 to 49 parts by weight, even more preferably 47.7 to 48.5 parts by weight, particularly preferably 47.7 to 49 parts by weight. 48 parts by weight or 47.9 to 48.3 parts by weight.

When component (B3) is included as component (B), the amount of component (B3) in the oil-based external composition of the present invention is, for example, 15 to 30% by weight, preferably 20 to 26% by weight, more preferably 22% by weight. -24% by weight, more preferably 22.6-23% by weight or 22.2-22.8% by weight.

Further, when component (B3) is included as component (B), the ratio of the content of component (B3) per 100 parts by weight of component (B) is determined based on the above content of each component, but preferably, Examples include 28 to 33 parts by weight, more preferably 28.2 to 31 parts by weight, still more preferably 28.2 to 29 parts by weight, even more preferably 28.7 to 29 parts by weight.

In addition, when the (B) component includes the (B1) component and the (B3) component, the ratio of the (B1) component to the (B3) component is determined by the above content of each component, but preferably (B1) The content of component (B3) per 1 part by weight of component is 1 to 2 parts by weight, more preferably 1.1 to 1.6 parts by weight, even more preferably 1.1 to 1.3 parts by weight, even more preferably 1 part by weight. .19 to 1.23 parts by weight, particularly preferably 1.21 to 1.23 parts by weight or 1.19 to 1.23 parts by weight.

(C) Dextrin fatty acid ester The oil-based external composition of the present invention contains a dextrin fatty acid ester as the component (C). An oil-based external composition containing tocopherols and an aqueous solvent has unstable dispersibility, but the oil-based external composition of the present invention has improved dispersion stability by containing component (C).

Dextrin fatty acid ester is a component known as an oily gelling agent. The dextrin fatty acid ester preferably includes esters of dextrin and higher fatty acids having 8 to 22 carbon atoms, and specifically, dextrin octanoate, dextrin laurate, dextrin palmitate, dextrin myristate, dextrin stearate, Examples include behenic acid dextrin, coconut oil fatty acid dextrin, (palmitic acid/octanoic acid) dextrin, and the like. These dextrin fatty acid esters may be used alone or in combination of two or more. Examples of commercial products of these dextrin fatty acid esters include "Leopard KL", "Leopard KE", "Leopard TT", and "Leopard TL" (all manufactured by Chiba Flour Sewing Co., Ltd.). Among these dextrin fatty acid esters, palmitic acid dextrin is preferred from the viewpoint of further enhancing the effects of the present invention.

In the oil-based external composition of the present invention, the content of component (C) is 0.15 to 0.37 parts by weight per 1 part by weight of component (b1). From the viewpoint of further enhancing the effects of the present invention, the content of component (C) per 1 part by weight of component (b1) is preferably 0.21 to 0.36 parts by weight, more preferably 0.21 to 0. 3 parts by weight or 0.26 to 0.36 parts by weight, more preferably 0.27 to 0.29 parts by weight.

The content of component (C) in the oil-based external composition of the present invention is not limited as long as the ratio with component (b1) is within the above range, and may be determined as appropriate depending on the dispersion stability improving effect to be imparted. It can be set, for example, from 0.5 to 1.7% by weight. From the viewpoint of further enhancing the effects of the present invention, the content of component (b1) is preferably 0.7 to 1.6% by weight, more preferably 1 to 1.7% by weight, even more preferably 1 to 1% by weight. .4 or 1.2 to 1.7% by weight, more preferably 1.2 to 1.4% by weight.

The ratio of component (A) to component (C) is determined based on the above-mentioned content of each component, but from the viewpoint of further enhancing the effects of the present invention, the ratio of component (A) to 1 part by weight of component (A) is determined based on the above content of each component. The content of component C) is 2.5 to 9 parts by weight, preferably 3.5 to 8.5 parts by weight, more preferably 5 to 8.5 parts by weight, even more preferably 5 to 7 parts by weight, or 6. 2 to 8.5 parts by weight, more preferably 6.3 to 6.7 parts by weight.

Furthermore, the ratio of component (B3) to component (C) is determined based on the above-mentioned content of each component, but from the viewpoint of further enhancing the effects of the present invention, the ratio of component (B3) to 1 part by weight of component (B3) is The content of component C) is 0.019 to 0.077 parts by weight, preferably 0.03 to 0.077 parts by weight, more preferably 0.043 to 0.077 parts by weight, even more preferably 0.043 to 0.077 parts by weight. Examples include 0.064 parts by weight or 0.056 to 0.077 parts by weight, more preferably 0.058 to 0.062 parts by weight.

(D) Aqueous solvent The oil-based external composition of the present invention contains an aqueous solvent as component (D). Although oil-based external compositions containing tocopherols and an aqueous solvent have unstable dispersibility, the oil-based external composition of the present invention can improve dispersion stability.

Examples of the aqueous solvent include water, lower alcohols (eg, ethanol, isopropanol, etc.), polyhydric alcohols (glycerin, propylene glycol, dipropylene glycol, 1,3-butylene glycol, etc.), and the like. These aqueous solvents may be used alone or in combination.

Among these aqueous solvents, water and polyhydric alcohols are preferred, and water and glycerin are more preferred.

The content of component (D) in the oil-based external composition of the present invention is, for example, 2 to 25. From the viewpoint of further enhancing the effects of the present invention, the content of component (D) is preferably 2 to 20% by weight, more preferably 2 to 19% by weight, and still more preferably 2 to 18% by weight.

Moreover, since the oil-based external composition of the present invention is excellent in the effect of improving dispersion stability, even if the content of component (D) is relatively large, the effect of improving dispersion stability can be effectively obtained. From this point of view, preferred examples of component (D) in the oil-based external composition of the present invention include preferably 5 to 20% by weight, more preferably 10 to 20% by weight, and even more preferably 15 to 20% by weight. , more preferably 16 to 20% by weight.

When containing water as component (D), the water content in the oil-based external composition of the present invention is, for example, 2 to 10% by weight, preferably 3 to 8% by weight, more preferably 4 to 6% by weight. It will be done.

The ratio of component (D) to component (B) is determined based on the above content of each component, but preferably the content of component (D) is 20 to 25 parts by weight per 100 parts by weight of component (B). Weight %, more preferably 22.5 to 24 weight %, still more preferably 22.8 to 23.5 weight %, still more preferably 22.8 to 23.2 weight %.

Other Components The oil-based external composition of the present invention may contain medicinal components other than the above-mentioned components, as necessary, within a range that does not impede the effects of the present invention. Such medicinal ingredients include, for example, anti-inflammatory agents, anti-aging agents, astringents, antioxidants, humectants, blood circulation promoters, antibacterial agents, bactericidal agents, desiccants, cooling agents, warming agents, and vitamins. Examples include amino acids, wound healing promoters, irritation relievers, analgesics, cell activators, enzyme components, crude drug components, and the like.

In addition, the oil-based external composition of the present invention may contain surfactants, thickeners, buffers, chelating agents, antioxidants, stabilizing agents, etc. other than the above-mentioned components, as necessary, within a range that does not impede the effects of the present invention. The composition may contain additives such as a softening agent, a preservative, a fragrance, a cooling agent, a coloring agent, a dispersing agent, a fluidizing agent, a humectant, and a wetting agent. Among these components, surfactants are preferred.

By including a surfactant in the oil-based external composition of the present invention, a more stable water-in-oil emulsion composition can be constructed. Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants, and preferably nonionic surfactants. Examples of nonionic surfactants include lipophilic nonionic surfactants and hydrophilic nonionic surfactants. As the nonionic surfactant, either a lipophilic nonionic surfactant or a hydrophilic nonionic surfactant, or both may be used, but preferably a hydrophilic nonionic surfactant is used. Use a surfactant.

Examples of hydrophilic nonionic surfactants include polyoxyethylene (hereinafter abbreviated as POE), POE sorbitan monolaurate (polysorbate 20), POE sorbitan monostearate (polysorbate 60), and POE sorbitan monooleate (polysorbate 80). ); POE sorbitan fatty acid esters such as POE sorbitol monooleate; POE glycerin fatty acid esters such as POE glycerin monoisostearate; POE alkyl ethers such as POE stearyl ether and POE cholestanol ether; POE nonylphenyl POE alkylphenyl ethers such as ethers, pluronic types such as Pluronic; POE/polyoxypropylene (hereinafter abbreviated as POP), POE/POP alkyl ethers such as cetyl ether, tetra-POE/tetra-POP ethylenediamine condensates such as Tetronic; POE castor oil, POE hydrogenated castor oil derivatives such as POE hydrogenated castor oil; POE beeswax and lanolin derivatives; alkanolamide; POE propylene glycol fatty acid ester; POE alkylamine; POE fatty acid amide, sucrose fatty acid ester; POE nonylphenyl formaldehyde Condensates; examples include alkyl ethoxydimethylamine oxide and trioleyl phosphoric acid. These hydrophilic nonionic surfactants may be used alone or in combination of two or more. Among these hydrophilic nonionic surfactants, POE sorbitan fatty acid ester is preferred, and POE sorbitan monooleate is more preferred.

When the oil-based external composition of the present invention contains a hydrophilic nonionic surfactant, the content of the hydrophilic nonionic surfactant is, for example, 0.3 to 4 parts by weight, preferably 0.5 to 4 parts by weight. 2.5 parts by weight, more preferably 0.8 to 1.5% by weight.

Formulation Form The formulation form of the oil-based external composition of the present invention is not particularly limited, and examples include liquid, semi-solid (gel, paste, cream, ointment) and solid forms. Since the present invention is excellent in the effect of improving dispersion stability, the effect of improving dispersion stability can be effectively obtained even in a semi-solid state containing a relatively large amount of aqueous solvent. From this point of view, a suitable formulation form of the oil-based external composition of the present invention includes a semi-solid form.

Specific examples of the oil-based external composition of the present invention include water-in-oil dispersions and water-in-oil emulsions, preferably water-in-oil emulsions. More specific dosage forms of the oil-based external composition of the present invention include those applied to the lips, skin, and hair, such as lip compositions such as lipstick, lip balm, and lip gloss; eye shadow, and eye liner. , cheek color, foundation, concealer, hair gel, hair wax, etc. Moreover, the oil-based external composition of the present invention may be any of general skin cosmetics, medicinal cosmetics, quasi-drugs, and pharmaceuticals, and preferably includes pharmaceuticals.

Method for producing an oil-based external composition The oil-based external composition of the present invention is prepared by using the above-mentioned components (A) to (D) and other components blended as necessary. It is prepared by mixing desired amounts of medicinal ingredients, additives, etc. in the usual order.

2. Method for Improving Dispersion Stability of Oil-Based Topical Compositions As mentioned above, in oil-based topical compositions containing tocopherols and an aqueous solvent, dispersion stability can be significantly improved by combining dextrin fatty acid ester in a predetermined ratio to beeswax. You can improve. Therefore, the present invention further comprises (A) tocopherol and/or a derivative thereof, (B) an oily base, and (D) an aqueous solvent, the component (B) containing (B1) a solid oil, In an oil-based external composition in which the component (B1) contains (b1) beeswax, the amount of (C) dextrin fatty acid ester is 0.15 to 0.37 parts by weight per 1 part by weight of the component (b1). Provided is a method for improving the dispersion stability of an oil-based external composition.

In the method for improving dispersion stability of an oil-based external composition of the present invention, improving dispersion stability refers to suppressing oil phase separation to construct a more stable dispersion system.

In the method for improving the dispersion stability of an oil-based external composition, the types and amounts of the components used, the form of the oil-based external composition, etc. are as shown in the column of "1. Oil-based external composition" above.

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto.

Test Examples Oil-based external compositions (ointment-like water-in-oil emulsion compositions) shown in Tables 1 to 4 were prepared. Specifically, an oil base and a surfactant, or an oil base, a surfactant, and tocopherol acetate were dissolved and mixed at 80°C in a 200 mL beaker, and the mixture was poured into a 100 mL beaker while thoroughly stirring with a stirrer. Add and emulsify the aqueous solvent dissolved and mixed at 80°C, and stir (3000 rpm, 30 seconds) at 80°C with a Disper (Robomix/Primix Co., Ltd.), then emulsifier (ET- 3A/Nikko Chemicals Co., Ltd.) by cooling to room temperature while stirring (150 rpm), an oil-based external composition was obtained in a glass bottle (25° C.). This oil-based external composition was obtained in a form containing air bubbles due to the stirring operation during preparation.

The properties, feeling of use, and dispersion stability of each of the obtained oil-based external compositions were evaluated based on the following criteria. The results are shown in Tables 1 to 4.

(Properties)
The oil-based external composition was filled into a lip balm tube container, and a trained panelist applied the oil-based external composition directly to the lips from the container, and evaluated the properties based on the following criteria.
◎: Easy to squeeze out an appropriate amount from the container, and there is no dripping at all.
○: It is easy to squeeze out the application from the container, and it is difficult to drip.
△: Easy to squeeze out the application from the container, but easy to drip.
×: Difficult to squeeze out the application from the container and easy to drip.

(Feeling of use)
The oil-based external composition was applied to the lips by a trained panelist, and the feeling of use was evaluated based on the following criteria.
○: Less stickiness and oil film feeling after application.
△: Slightly less sticky and oily feeling after application.
×: There is a lot of stickiness and oily feeling after application.

(Dispersion stability)
Dispersion stability was evaluated by storing the oil-based external composition (25° C.) in the form of bubbles still encapsulated at 50° C. for one month, and then classifying the appearance based on the following criteria.
◎: Almost no change was observed, and an excellent dispersion state was maintained.
○: A good dispersion state is maintained with only a slight seepage of the oil phase into the enclosed bubbles.
Δ: A large amount of oil phase seeps into the enclosed bubbles, and the dispersion state is slightly deteriorated.
×: A slight oil phase layer was formed on the top, and the dispersion state was poor.
XX: Many oil phase layers were formed on the top, and the dispersion state was extremely poor.

As shown in the comparison between Comparative Example 1 and Comparative Example 2, when tocopherol acetate is blended into an oil-based external composition containing an aqueous solvent, the dispersion stability deteriorates. As shown in Comparative Examples 3 and 4, this problem similarly occurs regardless of whether water or glycerin is used as the aqueous solvent. As shown in Comparative Examples 5 and 6, even if the ratio of semi-solid oil in the oily base is increased, the dispersion stability not only does not improve, but also the properties and feeling of use deteriorate. As shown in Comparative Example 7, when the ratio of solid oil in the oil base was increased, the properties were maintained well, and as shown in Comparative Example 8, when the ratio of solid oil was further increased, the properties were maintained well. Dispersion stability improves as the temperature decreases, but on the other hand, the usability deteriorates. Moreover, as shown in Comparative Examples 9 and 10, when the ratio of liquid oil in the oily base is increased, the feeling of use is maintained favorably, but the properties and dispersion stability are further deteriorated.

As shown in Comparative Example 11, when a small amount of palmitic acid dextrin, which is an oil-based gelling agent, was blended with beeswax, the dispersion stability tended to improve slightly, but the properties deteriorated. Further, as shown in Comparative Example 12, when a relatively large amount of palmitic acid dextrin was blended with white beeswax, the dispersion stability improved, but the properties also deteriorated in this case. On the other hand, as shown in Examples 1 to 4, by blending palmitic acid dextrin with beeswax at a predetermined ratio, the dispersion stability was significantly improved, and the properties and feeling of use were also good. Ta. Similar trends were observed in Examples 5 to 6, which were compared to Comparative Examples 13 to 15. Furthermore, as shown in Example 7, similar effects were observed when other medicinal ingredients were further added.

Formulation Example An oil-based external composition having the formulation shown in Table 5 was prepared. All of the oil-based external compositions exhibited excellent properties, and were also excellent in feel and dispersion stability.

Claims (8)

(A) tocopherol and/or an ester of tocopherol and an organic acid , (B) an oily base, (C) a dextrin fatty acid ester, and (D) an aqueous solvent, wherein the (B) component is (B1) a solid oil. The (B1) component contains (b1) beeswax, and the content of the (C) component is 0.15 to 0.37 parts by weight per 1 part by weight of the (b1) component. Oil-based external composition. The oil-based external composition according to claim 1, wherein the content of the component (C) is 0.5 to 1.8% by weight. The oil-based external composition according to claim 1 or 2, wherein the content of the component (C) is 2.5 to 9 parts by weight per 1 part by weight of the component (A). The oil-based external composition according to any one of claims 1 to 3, wherein the component (B) comprises (B2) a semi-solid oil and/or (B3) a liquid oil. When the composition (B3) is contained, the content of the component (C) is 0.019 to 0.077 parts by weight per 1 part by weight of the component (B3), according to claim 4. thing. The oil-based external composition according to claim 4, wherein when the component (B3) is contained, the component (B3) is 28 to 33 parts by weight based on 100 parts by weight of the component (B). The oil-based external composition according to any one of claims 1 to 6, wherein the content of the component (D) is 2 to 25% by weight. (A) contains tocopherol and/or an ester of tocopherol and an organic acid , (B) an oily base, and (D) an aqueous solvent, the (B) component contains (B1) solid oil, and the (B1) ) In an oil-based external composition containing component (b1) beeswax, (C) dextrin fatty acid ester is blended in an amount of 0.15 to 0.37 parts by weight per 1 part by weight of component (b1). A method for improving the dispersion stability of an oil-based external composition.