JP3902174B2 - Method for producing oil-in-water emulsion composition - Google Patents

Description

  The present invention relates to an oil-in-water emulsion composition that contains an amphipathic lipid, has a good emulsification stability of the amphipathic lipid even with a low concentration of surfactant, and is excellent in usability, and a method for producing the same.

  It is widely known that moisture in the stratum corneum is important in order to give moisture, flexibility to skin, mucous membrane, hair and the like. On the other hand, it is also known that this stratum corneum serves as a biological barrier layer and functions to retain the water of the skin (stratum corneum) and suppress moisture evaporation.

  In recent years, it has been shown that intercellular lipids present in the skin stratum corneum are deeply involved in the retention of stratum corneum and the barrier function. Therefore, in order to enhance the moisturizing effect, cosmetics containing amphiphilic lipids such as ceramide, which is a main component of intercellular lipids present in the skin stratum corneum, and similar substances have been proposed. However, these amphiphilic lipids have low solubility in water and remain solid up to a considerably high temperature, so that a large amount of surfactant is required especially for stable incorporation into an oil-in-water emulsion composition. The On the other hand, in general, it is desirable to reduce the amount of surfactant (for example, nonionic surfactant) used in cosmetics as much as possible.

  On the other hand, normal human skin is covered with a weakly acidic sebum film, and normally the skin pH is naturally controlled against contact with an alkaline substance from the outside. For example, the skin epidermis becomes weakly alkaline by being washed with a fatty acid soap, while normal skin is naturally neutralized with free fatty acids from sebum. In other words, external preparations or cosmetics applied to the skin have a weak acidity that is as close as possible to the pH of normal human skin, and have a positive effect on the skin, and are particularly preferred by people with sensitive skin. . Therefore, it has been studied to stably mix an intercellular lipid component with a small amount of surfactant in a weakly acidic cosmetic.

  Patent Document 1 discloses a stable emulsified composition by emulsifying an oil medium obtained by dissolving an amphiphilic lipid such as ceramide in a liquid oil having a melting point of less than 30 ° C. with an aqueous medium using a polyglycerol fatty acid ester. A method of obtaining an object is disclosed. However, in order to obtain a stable emulsion by this method, a large amount of polyglycerol fatty acid ester equivalent to that of the amphiphilic lipid is required, and in order to obtain a weakly acidic emulsion, an acid such as an organic acid is required. Substances must be added to adjust the pH.

  Further, Patent Document 2 attempts to stabilize amphiphilic lipids by using a nonionic surfactant and an anionic surfactant in combination. However, even in this combination, the amount of the surfactant to be used is large, and in the acidic region where the pH is 6 or less, the anionic surfactant tends to hardly function as an emulsifier.

JP 2002-114631 A JP-A-4-193814

  The present invention is an oil-in-water emulsion composition that can stably emulsify an oil phase containing an amphiphilic lipid such as ceramide, which is generally difficult to mix in an aqueous medium, with a low concentration of a surfactant, and has an excellent usability. An object of the present invention is to provide a manufacturing method thereof.

  The inventor can stably emulsify the amphiphilic lipid with a low concentration of surfactant by using an amphiphilic lipid in combination with a specific cationic surfactant and a divalent or trivalent alcohol. It was found that an oil-in-water emulsified composition excellent in the above can be obtained.

That is, the present invention mixes (A) at least one quaternary ammonium salt type cationic surfactant represented by the following general formula (1) and (C) at least one divalent and trivalent alcohol. Then, (B) The manufacturing method of the oil-in-water-type emulsion composition which adds the oil phase containing an amphiphilic lipid and adds an aqueous medium after that is provided.

(In the formula, R ¹ and R ² are each independently a linear or branched saturated or unsaturated hydrocarbon group having 16 to 22 carbon atoms, and R ³ and R ⁴ are each independently one having 1 carbon atom. ˜3 alkyl groups, and X ⁻ is a salt-forming anion.)

  The oil-in-water emulsion composition of the present invention containing an amphipathic lipid such as ceramide forms a thickened structure having a thixotropy that has a high liquid crystal structure stability when allowed to stand and a good disintegration property when used for coating or the like. Therefore, it has excellent emulsification stability during storage and excellent usability. Furthermore, since the surfactant has a low concentration and is also weakly acidic, it is less irritating to the skin. Therefore, the oil-in-water emulsion composition of the present invention is useful as an externally applied drug or cosmetic, particularly a cosmetic, which is excellent in emulsion stability and feeling of use and has little irritation to the skin.

  The production method of the present invention is a suitable method for producing the above oil-in-water emulsion composition. The amphiphilic lipid is stably emulsified with a small amount of a surfactant, and has an increased thixotropy with excellent usability. A viscous structure can be formed. This production method is advantageous in terms of productivity because a weakly acidic emulsion composition can be obtained without particularly adjusting the pH.

  The oil-in-water emulsion composition of the present invention comprises (B) an oil phase containing amphiphilic lipids and (C) alcohols selected from divalent and trivalent alcohols (hereinafter referred to as alcohols (C)). The emulsified composition emulsified with (A) a quaternary ammonium salt type cationic surfactant represented by the above formula (1) (hereinafter referred to as a cationic surfactant (A)). It is.

  In the emulsified composition of the present invention, the cationic surfactant (A) and the amphiphilic lipid (B) are associated in an aqueous medium containing the alcohol (C) to form a liquid crystal (or α-gel structure). And a thickened structure is formed. The resulting thickened structure exhibits viscous behavior and can be in a stable state against coalescence of oil droplets and creaming. Such a combination can form a highly stable liquid crystal structure even when the concentration of the cationic surfactant (A) is low, so that the amount of the surfactant used can be reduced. Here, since the thickened structure has optical anisotropy, it can be confirmed with a polarizing microscope or the like.

  Further, since the emulsified composition of the present invention exhibits thixotropic properties, the above thickened structure maintains a stable liquid crystal structure in a stationary state, but the liquid crystal structure is easily broken at the time of application, and the application part is thin and uniform. As it stretches, it has a refreshing and fresh feeling.

  Furthermore, it is preferable that the emulsified composition of the present invention is weakly acidic in terms of irritation to the skin and feeling of use. Specifically, the pH is preferably 4 or more and less than 7.

  In the present invention, the combination of the above components (A), (B), (C) and (D) makes it possible to weakly emulsify even if the pH is not adjusted to acidic by adding a pH adjuster or the like. A composition can be obtained.

  The cationic surfactant (A) used in the present invention is a cationic surfactant having a quaternary ammonium salt structure having two long-chain hydrocarbon groups which may have a substituent in one molecule. is there. As the cationic surfactant (A), those represented by the following formula (1) are used particularly from the viewpoint of affinity for the skin.

(In the formula, R ¹ and R ² are each independently a linear or branched saturated or unsaturated hydrocarbon group having 16 to 22 carbon atoms, and R ³ and R ⁴ are each independently one having 1 carbon atom. ˜3 alkyl groups, and X ⁻ is a salt-forming anion.)

Examples of the hydrocarbon groups R ¹ and R ² in the formula (1) include an alkyl group or an alkenyl group. Examples of salt-forming anions include halogen ions, phosphate ions, acetate ions, lactate ions, monoalkyl sulfate ions, and the like.

  Specific examples of the cationic surfactant include dicetyldimethylammonium chloride, distearyldimethylammonium chloride, diaralkyldimethylammonium chloride, dibehenyldimethylammonium chloride, and the like. Of these, dicetyldimethylammonium chloride and distearyldimethylammonium chloride are also available as commercial products, and examples include Varisoft TA-432CG, Varisoft TA-100 (Goldschmidt), and Quartamin D-86P (Kao). .

  Of these cationic surfactants, dicetyldimethylammonium chloride, distearyldimethylammonium chloride, and the like are preferable because they have an affinity for the skin.

  The content of the cationic surfactant (A) is in the total composition of the oil-in-water emulsion composition from the viewpoint of forming a suitable liquid crystal structure with the amphiphilic lipid (B) and alcohols (C) described later. It is 0.1-1 mass%, Preferably it is 0.5-1 mass%.

  In the present invention, the amphiphilic lipid (B) is a substance that has both a hydrophilic part and a hydrophobic part in the molecule and is solid at 25 ° C. Examples of the amphiphilic lipid (B) include cholesterols such as cholesterol, cholesterol ester, and cholesterol sulfate; higher fatty acids such as stearic acid and palmitic acid; cetyl alcohol, stearyl alcohol, behenyl alcohol, batyl alcohol, and chimyl alcohol. Higher alcohols and related compounds thereof; glycerin fatty acid esters.

  Further, examples of amphiphilic lipids that are particularly excellent in skin barrier function and moisturizing function and have an excellent skin roughness improving effect include amide compounds represented by the following general formulas (2) to (4).

(Wherein R ¹¹ is a linear or branched, saturated or unsaturated hydrocarbon group having 8 to 50 carbon atoms which may be substituted with one or more hydroxyl groups, or R ¹³ —COO—R ^14. Wherein R ¹³ is a linear or branched saturated or unsaturated hydrocarbon group having 8 to 30 carbon atoms, and R ¹⁴ is a carbon number that may be substituted with one or more hydroxyl groups. 8 to 40 represents a linear or branched, saturated or unsaturated divalent hydrocarbon group, and R ¹² represents a linear or branched group having 8 to 50 carbon atoms which may be substituted with one or more hydroxyl groups. Represents a saturated or unsaturated hydrocarbon group in the chain.)

(In the formula, R ¹⁵ represents a C 7-25 linear or branched saturated or unsaturated hydrocarbon group which may be substituted with one or more hydroxyl groups, and R ¹⁶ represents one or more R ¹⁷ represents a hydrogen atom, 2-hydroxyethyl group, or 2, 3 or a straight chain or branched chain saturated or unsaturated hydrocarbon group or alkoxy group that may be substituted with a hydroxyl group. -Represents a dihydroxypropyl group, Y represents a hydrogen atom or a hydroxyl group.

(In the formula, each R ¹⁸ independently represents a linear or branched hydrocarbon group having 1 to 22 carbon atoms which may be substituted with a hydroxyl group and / or an alkoxy group, and each R ¹⁹ independently represents And a straight or branched divalent hydrocarbon group having 1 to 12 carbon atoms, and R ²⁰ represents a straight or branched divalent hydrocarbon group having 1 to 42 carbon atoms.)

In the general formula (2), R ¹¹ is preferably a linear or branched saturated or unsaturated hydrocarbon group having 8 to 30 carbon atoms which may be substituted with one or more hydroxyl groups, or R ^13. It is a group represented by —COO—R ¹⁴ —. Here, R ¹³ is linear or saturated or unsaturated hydrocarbon group branched, R ¹⁴ is 1 or more straight of carbon atoms which may be have 8-30 substituted with a hydroxyl group having 8 to 30 carbon atoms Chain or branched chain saturated or unsaturated divalent hydrocarbon groups are preferred. R ¹² is preferably a linear or branched saturated or unsaturated hydrocarbon group having 8 to 30 carbon atoms which may be substituted with one or more hydroxyl groups. In particular, R ¹¹ and R ¹³ are preferably a linear alkyl group having 8 to 30 carbon atoms, and R ¹⁴ is a linear alkylene group having 8 to 30 carbon atoms.

  The amide compound represented by the general formula (2) is preferably Robson KJ et al., J. Lipid Res., 35, 2060 (1994) or Wertz PW et al., J. Lipid Res., 24,759. (1983) et al. Are known type 1-7 ceramides. These can be produced by extraction and reaction modification from animals and plants, or total synthesis. Moreover, as a commercial item of the amide compound represented by Formula (2), Ceramide III, Ceramide IIIB, Ceramide IIIA, Ceramide IV, Phytoceramide I (above, Degussa), Ceramide II (Sederma), Ceramide TIC- And 001 (Takasago Inc.).

In the general formula (3), R ¹⁵ is preferably a linear or branched saturated or unsaturated hydrocarbon group having 14 to 22 carbon atoms which may be substituted with one or more hydroxyl groups, In particular, a linear alkyl group is preferable. Among these, a pentadecyl group and a trihydroxypentadecyl group are more preferable.

R ¹⁶ is preferably a linear alkyl group or alkoxy group having 8 to 24 carbon atoms. Among these, a nonyl group and a hexadecyloxy group are more preferable.

Regarding the combination of R ¹⁶ and R ¹⁷ , when R ¹⁷ is a hydrogen atom or a 2-hydroxyethyl group, R ¹⁶ is preferably a linear alkoxy group, and R ¹⁷ is a 2,3-dihydroxypropyl group. In some cases, R ¹⁶ is preferably a linear alkyl group.

Further, regarding the combination of Y and R ¹⁷ , when R ¹⁷ is a hydrogen atom or a 2-hydroxyethyl group, Y is preferably a hydroxyl group, and when R ¹⁷ is a 2,3-dihydroxypropyl group, Y is preferably a hydrogen atom.

  Specific examples of the amide compound represented by the general formula (3) include compounds represented by the following formulas (5), (6) and (7).

  Further, the amide compound of formula (3) is prepared by the method described in JP-A-62-228048, for example, acylating a reaction product obtained from glycidyl ether and ethanolamine, and then selectively hydrolyzing the ester group. It can manufacture by the method to do.

  Among these, the amide compound represented by the general formula (5) is preferable, and Sofcare Ceramide SL-E (N- (3-hexadecyloxy-2-hydroxypropyl) -N-2-hydroxyethylhexadecanamide, It is commercially available as Kao Corporation.

R ¹⁸ of the amide compound represented by the general formula (4) is a straight chain having 1 to 22 carbon atoms which may be substituted with 1 to 3 groups selected from a hydroxyl group and an alkoxy group having 1 to 6 carbon atoms. A chain or branched alkyl group is preferred, and may be substituted simultaneously with a hydroxyl group and an alkoxy group.

For example, an alkyl group having 1 to 18 carbon atoms, a mono- or di-hydroxyalkyl group having 1 to 18 carbon atoms, an alkyl group having 1 to 18 carbon atoms substituted by an alkoxy group having 1 to 6 carbon atoms, and a hydroxyl group and carbon The C1-C18 alkyl group which the C1-C6 alkoxy group substituted is preferable. In particular, an alkyl group having 1 to 18 carbon atoms, a mono- or dihydroxyalkyl group having 2 to 12 carbon atoms, an alkyl group having 2 to 12 carbon atoms substituted by an alkoxy group having 1 to 6 carbon atoms, a hydroxyl group and carbon A C2-C12 alkyl group substituted by a C1-C6 alkoxy group is more preferred. Of these, R ¹⁸ is more preferably a 2-hydroxyethyl group, a methyl group, a dodecyl group, or a 2-methoxyethyl group.

R ¹⁹ is preferably a linear or branched alkylene group having 1 to 12 carbon atoms, and more preferably a linear or branched alkylene group having 2 to 6 carbon atoms. Among these, an ethylene group and a trimethylene group are more preferable.

R ²⁰ is preferably a linear or branched divalent hydrocarbon group having 2 to 34 carbon atoms, and further represents a linear or branched alkylene group having 1 to 34 carbon atoms or 1 to 4 double bonds. The alkenylene group which has has is preferable, and the C2-C24 linear or branched alkylene group or the alkenylene group which has 1-4 double bonds is especially preferable. Among these, 7,12-dimethyloctadecamethylene group, 7,12-dimethyl-7,11-octadecadienylene group, octadecamethylene group, octamethylene group, decamethylene group, undecamethylene group, tridecamethylene group Is more preferable.

As the amide compound represented by the general formula (4), a compound in which R ¹⁸ , R ¹⁹ and R ²⁰ are each combined with groups in the above-described more preferable range is preferable.

  The amide compound of the general formula (4) is, for example, a corresponding dicarboxylic acid or a reactive derivative thereof (ester, acid halide, acid anhydride, etc.) as in the method described in International Publication No. 00/61097 pamphlet or the like. And the amine can be efficiently condensed.

  As the amphiphilic lipid used in the oil-in-water emulsion composition of the present invention, in particular, compounds represented by the following formulas (8) to (14) belonging to the amide compound represented by the general formula (4) Is particularly preferred.

  (B) The content of the amphiphilic lipid is preferably 0.1% by mass or more in the total composition of the oil-in-water emulsion composition in order to sufficiently exert the skin barrier function and moisture retention function. Considering the balance with storage stability, the total composition is preferably 0.1 to 20% by mass, and more preferably 0.1 to 10% by mass.

  The mass ratio (A: B) of the cationic surfactant (A) to the amphiphilic lipid (B) is 10: 1 to 1:20 from the viewpoint of expression of effects on the skin and formation of a suitable liquid crystal structure. It is preferable that it is 10: 1 to 1:10.

  In the present invention, the alcohol (C) selected from divalent and trivalent alcohols can dissolve and disperse the above-mentioned cationic activator when blended in an emulsified cosmetic. After mixing the cation activator (A) with the alcohol (C) and mixing with the oil component containing the amphiphilic lipid (B), a suitable liquid crystal structure is formed even at a low concentration of the cation activator. be able to.

  Examples of such alcohols (C) include ethylene glycol, polyethylene glycol (average molecular weight 200 to 400), propylene glycol, dipropylene glycol, 1,3-butanediol, glycerin, polyglycerin (degree of polymerization 2 to 5) and the like. Is mentioned. Of these, glycerin and ethylene glycol are particularly preferred.

  The content of the alcohols (C) has a good feeling in use, forms a suitable liquid crystal structure, and obtains a stable emulsion. It is preferable to set it to -40 mass%, especially 5-20 mass%.

  In the oil-in-water emulsion composition of the present invention, in addition to the amphiphilic lipid (B), liquid, semisolid or solid oily components, such as hydrocarbon oils, which are usually used in cosmetics , Ester oil, ether oil, silicone oil, fluorine oil, and the like.

  Examples of liquid oil include vegetable oil such as jojoba oil; animal oil such as liquid lanolin; hydrocarbon oil such as liquid paraffin and squalane; diisostearyl malate, octyldodecyl lactate, isotridecyl isononanoate, isopropyl isostearate, octyl myristate Ester oils such as dodecyl and neopentyl glycol dicaprate; glycerin derivatives; amino acid derivatives; silicone oils such as dimethylpolysiloxane, dimethylcyclopolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, higher alcohol-modified organopolysiloxane; Fluorine oils such as polyether and perfluoroalkyl ether silicone are exemplified.

  Examples of solid or semi-solid oily components include vegetable waxes such as jojoba wax; alkyl glyceryl ethers such as glycerin monostearyl ether and glycerin monocetyl ether; petrolatum, lanolin, ceresin, microcrystalline wax, carnauba wax, and candelilla wax. Waxes.

  The content of these oily components is usually 0.1 to 30% by mass, preferably 1 to 20% by mass in the entire composition.

  The emulsion composition intended for ultraviolet (UV) care cosmetics can appropriately contain a UV protective agent called a UV absorber or a UV scattering agent. As the UV absorber, compounds such as paramethoxycinnamic acid, benzophenone, urocanic acid, paraaminobenzoic acid, salicylic acid, benzoylmethane, triazine, anthranilic acid, and the like can be used. Powders such as titanium dioxide, zinc oxide, and iron oxide can be used.

  The content of such a UV protective agent is usually 1 to 40% by mass, preferably 1 to 20% by mass in the total composition.

  Since such UV care cosmetics have high water resistance and are not easily removed by sweat or water, the UV protection effect has good durability while being an oil-in-water emulsion composition.

  Content of the water (D) which forms the water phase continuous phase of the oil-in-water emulsion composition which concerns on this invention is 10-90 mass% normally in the whole composition, Preferably it is 40-90 mass%. As an aqueous phase component other than water, water-soluble components that can be used in normal cosmetics other than the alcohols such as ethyl alcohol, various water-soluble medicinal agents, antioxidants, preservatives, bactericides, salts, amino acids, Saccharides, chelating agents, thickeners, pigments, fragrances and the like can be blended within a qualitative and quantitative range that does not impair the purpose and effect of the present invention.

  In particular, the oil-in-water emulsion composition of the present invention was separately mixed with the first step of adding at least one cationic surfactant (A) to at least one alcohol (C). A second step of adding an oily dispersed phase containing the amphiphilic lipid (B) to the mixture obtained in the first step, and a third step of adding an aqueous medium to the mixture obtained in the second step. It is preferable to manufacture by.

  A mixture obtained by adding a cationic surfactant to an alcohol such as glycerin is mixed with an oil phase containing an amphiphilic lipid, and then added to an aqueous phase containing an aqueous component other than the alcohol for emulsification. As a result, a stable emulsified state is obtained without causing separation of the oil phase containing the amphiphilic lipid.

  That is, by preparing an emulsified composition by such a procedure, a cationic surfactant and an amphiphilic lipid form a liquid crystal structure in a polyhydric alcohol, and the resulting thickened structure is a combination of oil droplets. First, it can take a stable state against creaming. Here, when the amphiphilic lipid (B) is mixed with other components such as an oily component, the mixture may be heated as necessary to improve the solubility or dispersibility.

  The oil-in-water emulsion composition of the present invention exhibits an emulsion or cream appearance, and the viscosity at 25 ° C. is preferably about 1,000 to 100,000 mPa · s. The viscosity can be measured using a B-type viscometer.

  The oil-in-water emulsified composition of the present invention is useful as a drug for external use or a cosmetic, particularly a cosmetic, and depending on its use, any agent such as a lotion, gel, cream, UV care cosmetic, aerosol foam, etc. Can be a mold.

Hereinafter, the present invention will be described more specifically with reference to examples. The footnotes in the table are as follows.
* 1: Kao Corporation, Sofcare Ceramide SL-E
* 2: Goldschmit, Varisoft TA-100
* 3: Goldschmit, Varisoft BT-85
* 4: Kao Corporation, Exepearl DG-MI
* 5: Shin-Etsu Chemical Co., Ltd., Silicone KF-96A (10cs)

(Evaluation item)
(1) Presence / absence of formation of thickened structure After a small amount of the emulsified composition was placed on a slide glass and a cover glass was applied from above, optical anisotropy was confirmed with a polarizing microscope (Nikon ECLIPSE E600 POL).

(2) Appearance The state immediately after the preparation of the emulsified composition was judged to be good in the case of a uniform emulsified state, and separated when separation was observed. Thereafter, about 40 g of the emulsified composition was put into a 50 mL wide-mouth glass bottle, and the state of the emulsified product after being stored in a thermostatic bath at 50 ° C. and 5 ° C. for 1 month was visually observed according to the following criteria.

<Evaluation criteria>
○: No separation is observed △: Some separation is observed ×: Clear separation is observed (a problem level in product characteristics)

(3) Viscosity measurement About 40 g of the emulsified composition was placed in a 50 mL wide-mouth glass bottle, submerged in a water bath maintained at 25 ° C. so that the whole except for the lid of the bottle was immersed, and held in that state for 2 hours. Immediately after 2 hours, the glass bottle was pulled out of the water bath, and the viscosity was measured using a B-type viscometer (model B8R, manufactured by Tokyo Keiki Co., Ltd.) to determine the viscosity at 25 ° C.

(4) pH measurement The emulsified composition was put in a glass bottle with a lid, immersed in a water bath maintained at 25 ° C. for 2 hours, the glass bottle was lifted from the water bath, and then measured with a pH meter (pH METER F-22 manufactured by HORIBA).

(Example 1 and Comparative Example 1)
According to the composition of Table 1, an oil-in-water emulsion composition was produced by the following procedure and evaluated. The results are shown in Table 1.

<Manufacturing method>
Components (1) and (2) are uniformly dissolved and dispersed at 80 ° C. to obtain an oil phase. Separately, the cation activator of component (3) or (4) is added to the alcohol of component (5), dissolved uniformly at 80 ° C., and the above oil phase is added while maintaining the temperature. Furthermore, water of component (6) is added and emulsified using a homogenizer while maintaining at 80 ° C. to obtain an emulsion. Cool to room temperature (25 ° C.) while stirring.

(Example 2) Emulsion According to the composition of Table 2, an emulsion was prepared in the same procedure as in Example 1. That is, components (1) to (4) are uniformly dissolved and dispersed at 80 ° C. to obtain an oil phase. Further, the cation activator of component (5) is added to the alcohol of component (6), dissolved uniformly at 80 ° C., and the above oil phase is added while maintaining the temperature. Separately, an aqueous phase obtained by mixing components (7) to (8) at 80 ° C. is added to the obtained oil phase and emulsified using a homogenizer while maintaining at 80 ° C. to obtain an emulsion. Cool to room temperature (25 ° C.) while stirring.

  The obtained emulsion had a viscosity of 8000 mPa · s and a pH of 5.4. Moreover, the emulsion stability after 1-month storage at 5 degreeC and 50 degreeC was favorable.

(Example 3) Cream According to the composition of Table 3, a cream was prepared in the same procedure as in Example 2.
The cream thus obtained had a viscosity of 50000 mPa · s and a pH of 5.2. The emulsion stability after storage at 5 ° C. and 50 ° C. for 1 month was good.

(Example 4) UV emulsion A UV emulsion was prepared in the same procedure as in Example 1 according to the composition shown in Table 4. That is, components (1) to (5) are uniformly dissolved and dispersed at 80 ° C. to obtain an oil phase. Further, the cation activator of component (7) is added to the alcohol of component (8), dissolved uniformly at 80 ° C., and the above oil phase is added while maintaining the temperature. Separately, an aqueous phase obtained by mixing components (6) and (9) to (10) at 80 ° C. is added to the obtained oil phase and emulsified using a homogenizer while maintaining at 80 ° C. to obtain an emulsion. Cool to room temperature (25 ° C.) while stirring.

The obtained UV emulsion had a viscosity of 12000 mPa · s and a pH of 6.2. The emulsion stability after storage at 5 ° C. and 50 ° C. for 1 month was good.
As a result of the use test, the durability of the UV protection performance was also good.

(Example 5) UV cream According to the composition of Table 5, UV cream was prepared in the same procedure as in Example 1. That is, components (1) to (7) are uniformly dissolved and dispersed at 80 ° C. to obtain an oil phase. Further, the cationic activator of component (8) is added to the alcohols of component (9), dissolved uniformly at 80 ° C., and the above oil phase is added while maintaining the temperature. Separately, an aqueous phase obtained by mixing components (10) to (11) at 80 ° C. is added to the obtained oil phase and emulsified using a homogenizer while maintaining at 80 ° C. to obtain an emulsion. Cool to room temperature (25 ° C.) while stirring.

The cream thus obtained had a viscosity of 44000 mPa · s and a pH of 4.9. The emulsion stability after storage at 5 ° C. and 50 ° C. for 1 month was good.
As a result of the use test, the durability of the UV protection performance was also good.

(Examples 6 to 8) Emulsion or cream According to the composition of Table 6, an emulsion or cream was prepared in the same procedure as in Example 2. That is, components (1) to (5) are uniformly dissolved and dispersed at 80 ° C. to obtain an oil phase. Further, the cation activator of component (6) is added to the alcohol of component (7), dissolved uniformly at 80 ° C., and the above oil phase is added while maintaining the temperature. Separately, an aqueous phase obtained by mixing components (8) to (10) at 80 ° C. is added to the obtained oil phase and emulsified using a homogenizer while maintaining at 80 ° C. to obtain an emulsion. Cool to room temperature (25 ° C.) while stirring.

  The viscosity and pH of the obtained emulsion or cream are also shown in Table 6. In any case, the emulsified state was good, and the emulsion stability after storage for 1 month at 5 ° C and 50 ° C was also good.

Claims (3)

  (A) After mixing at least one quaternary ammonium salt type cationic surfactant represented by the following general formula (1) and (C) at least one divalent and trivalent alcohol, (B ) A method for producing an oil-in-water emulsion composition, wherein an oil phase containing an amphiphilic lipid is added, and then an aqueous medium is added.

(Wherein R ¹ And R ² Are each independently a straight chain or branched chain saturated or unsaturated hydrocarbon group having 16 to 22 carbon atoms, R ^Three And R ^Four Are each independently an alkyl group having 1 to 3 carbon atoms, and X ⁻ Is a salt-forming anion. )   The method for producing an oil-in-water emulsion composition according to claim 1, wherein the amphiphilic lipid (B) is an amide compound represented by the following general formulas (2) to (4).

(Wherein R ¹¹ Is a linear or branched, saturated or unsaturated hydrocarbon group having 8 to 50 carbon atoms which may be substituted with one or more hydroxyl groups, or R ¹³ ―COO-R ¹⁴ -A group represented by ¹³ Is a linear or branched saturated or unsaturated hydrocarbon group having 8 to 30 carbon atoms, R ¹⁴ Represents a linear or branched, saturated or unsaturated divalent hydrocarbon group having 8 to 40 carbon atoms which may be substituted with one or more hydroxyl groups. R ¹² Represents a linear or branched, saturated or unsaturated hydrocarbon group having 8 to 50 carbon atoms which may be substituted with one or more hydroxyl groups. )

(Wherein R ¹⁵ Represents a straight-chain or branched saturated or unsaturated hydrocarbon group having 7 to 25 carbon atoms which may be substituted with one or more hydroxyl groups, and R ¹⁶ Represents a linear or branched saturated or unsaturated hydrocarbon group or alkoxy group having 8 to 26 carbon atoms which may be substituted with one or more hydroxyl groups. R ¹⁷ Represents a hydrogen atom, 2-hydroxyethyl group or 2,3-dihydroxypropyl group. Y represents a hydrogen atom or a hydroxyl group. )

(Wherein R ¹⁸ Each independently represents a linear or branched hydrocarbon group having 1 to 22 carbon atoms which may be substituted with a hydroxyl group and / or an alkoxy group, and R ¹⁹ Each independently represents a linear or branched divalent hydrocarbon group having 1 to 12 carbon atoms; ²⁰ Represents a linear or branched divalent hydrocarbon group having 1 to 42 carbon atoms. )   The manufacturing method of the oil-in-water type emulsion composition of Claim 1 or 2 whose content of the said cationic surfactant (A) in the oil-in-water type emulsion composition obtained is 0.1-1 mass%.