JPH0753648B2 - Oil-in-water emulsion cosmetic - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a stable oil-in-water emulsified cosmetic composition having excellent emulsification properties with a highly safe ionic surfactant, and having a moist feeling until the next morning. The present invention relates to an oil-in-water type emulsified cosmetic having a long-lasting skin effect.

[Prior Art] Conventionally, attempts have been made to use an ionic surfactant as an oil thickening / gelling agent and an emulsifier. For example, an ionic surfactant, a polyhydric alcohol, and an oil phase component are mixed. ,
An oil-in-water emulsion obtained by obtaining a stable polyhydric alcohol oil-in-water non-aqueous emulsion and then adding water thereto is known (JP-A-57-7235). Further, an emulsified composition containing an ionic surfactant, a water-soluble polyhydric alcohol having two or more hydroxyl groups in the molecule, and an oil phase component is mixed with water containing a higher alcohol having 10 to 30 carbon atoms. An oil-in-water emulsion composition obtained by the above method is also known (JP-A-59-69).
No. 38).

[Problems to be Solved by the Invention] However, when applied to cosmetics and the like, it is demanded to have high stability to the human body, and among ionic surfactants, safety is high among general consumers. There were many people who felt anxious, and many of them were not expected to have an effect on the skin after use.

[Means for Solving the Problems] In view of the above points, the present inventors have conducted intensive studies on safety and stabilization methods for oil-in-water emulsion cosmetics using an ionic surfactant, and as a result, It has been found that a combination of N-long-chain acylmethyl taurine salt as a surfactant and a water-soluble polyhydric alcohol prepared so that the solubility parameter is 12.5 to 18 is particularly effective,
The present invention has been completed. Further, in this combination, it was found that the combined use of N-long-chain acylmethyl taurine salt and lecithin as the ionic surfactant further improves the stability. The oil-in-water emulsified cosmetic composition of the present invention was also excellent in the skin effect of maintaining a moist feeling until the next morning due to the action of the N-long-chain acylmethyl taurine salt.

That is, the present invention relates to an N-long-chain acylmethyl taurine salt and one or two selected from water-soluble polyhydric alcohols.
A combination of two or more kinds or a combination of these and water, wherein the solubility parameter is adjusted to 12.5 to 18, and an emulsion composition containing an oil phase component, water is further added. In the oil-in-water emulsified cosmetic and the oil-in-water emulsified cosmetic described above, a phospholipid and / or a salt thereof is used in combination with an N-long-chain acylmethyl taurine salt in obtaining an emulsified composition. It is an oil-in-water emulsion cosmetic that does.

In particular, the N-long-chain acylmethyl taurine salt has been applied as a cleaning agent, but has not been found to be an application as an emulsifying agent by utilizing its characteristics. This time, they have found that the effect of the emulsifier is significantly enhanced by applying it to an oil-in-water emulsion cosmetic.

The structure of the present invention will be described below.

The N-long chain acylmethyl taurine salt used in the present invention is
A condensate of fatty acid and N-methyltaurine salt, which is an amide sulfonate type anionic surfactant and has a structure similar to that of taurocholic acid, which is an in vivo surfactant present in human and animal bile. It has high quality.

Regarding the method for producing N-long-chain acylmethyl taurine salt, dehydrochlorination reaction of fatty acid chloride and N-methyl taurine salt in the presence of alkali dehydration reaction of fatty acid and N-methyl taurine salt fatty acid isopropenyl ester and N -Deacetone reaction with methyl taurine salt, etc.

The fatty acid has 12 to 26 carbon atoms, and lauric acid, myristic acid, palmitic acid, and stearic acid are particularly preferable.

Examples of the salt-forming base include triethanolamine, sodium hydroxide, potassium hydroxide, arginine, lysine, histidine, ornithine, oxylysine, and the like. Of these, the basic amino acids can be used regardless of whether they are D-form, L-form or DL-form.
The base may be used alone or in combination of two or more.

The solubility parameter is, for example, Polymer hand book (EHImmergut, Interscience Publ
is used to measure the compatibility (affinity) of thermodynamic properties of a solvent, and the two solvents have almost the same value. Are said to mix with each other. The dissolution parameters can be calculated from the heat of vaporization, from van der Waals gas constants, from critical pressure, and from surface tension. I used the one.

δ = (ΔE / V) ^1/2 ……… (1) ΔE = ΔH-RT ……… (2) ΔH = 23.7Tb-0.02Tb ² −2950 ……… (3) δ: Dissolution parameter ΔE: Evaporation Energy V: Molecular volume ΔH: Heat of vaporization Tb: Boiling point (° K) Correction: For alcohol Add 1.4 to the calculated value.

Table 1 shows the solubility parameters of the water-soluble polyhydric alcohol and water measured by the above method. What can be used in the present invention is one or a combination of two or more kinds selected from water-soluble polyhydric alcohols or a combination of these and water, which is prepared so that the solubility parameter is 12.5 to 18. . Hereinafter, it will be referred to as the water-soluble polyhydric alcohols of the present invention.

The solubility parameter of the mixture is calculated by the following equation (2
For a mixture of seeds).

x _1, x _2: respective molar fraction V _1, V _2: each molecular volume [delta] _1, [delta] _2: wherein each solubility parameter, mole fraction is determined by the following equation.

_{x 2 = 1-x 1 W} 1, W 2: each formulation weight M _1, M _2: For each molecular weight reference also showed a molecular weight and molecular volume in Table 1.

Water-soluble polyhydric alcohols usable in the present invention include, for example, glycols such as propylene glycol, 1,3-butylene glycol, dipropylene glycol, ethylene glycol, and polyethylene glycol, and glycerol such as glycerin, diglycerin, and polyglycerin. , A saccharide such as sorbitol, maltitol, sucrose, starch, reduced starch, lactitol, etc., one or more kinds selected from pentaerythritol, or a combination of these with water and a solubility parameter of 12.5 to It was prepared to be 18.

Next, as the oil phase component, usually used in the field of cosmetics,
Those that are safe for the human body can be used. For example, olive oil. Vegetable oils such as castor oil, waxes such as beeswax, lanolin, candelilla wax, and wax.
Examples include hydrocarbons such as liquid paraffin, squalane, petrolatum, and paraffin wax, higher alcohols such as cetanol, stearyl alcohol, and behenyl alcohol, other ester oils, and silicone oils.

The phospholipid used in the present invention is a phospholipid extracted from plants such as soybean, corn, peanut, rapeseed, and wheat, animals such as egg yolk and cow, and microorganisms such as Escherichia coli, and phosphatidic acid, phosphatidylglycerin, and phosphatidylinositol. -Phosphatidylethanolamine-phosphatidylmonomethylethanolamine-phosphatidyldimethylethanolamine-phosphatidylcholine (lecithin) -phosphatidylserine-bisphosphatidic acid-diphosphatidylglycerin (cardiolipin) and other glycerophospholipids, and sphingophospholipids such as sphingomyelin. Further, those obtained by hydrogenating these can also be mentioned. Particularly, hydrogenated phospholipids are preferable because they have very high stability.
These may be used alone or in combination of two or more.

When using phospholipids as salts, substances that form salts include inorganic bases such as lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, and ammonium hydroxide, and arginine, lysine, histidine, ornithine, and the like. Examples thereof include basic amino acids, basic oligopeptides having basic amino acids as residues, and basic amines such as monoethanolamine / diethanolamine / triethanolamine. The phospholipid salt may be used alone or in combination of two or more.

In the emulsified composition of the present invention, the blending amount of the N-long chain acylmethyl taurine salt and the water-soluble polyhydric alcohol of the present invention prepared so that the solubility parameter is 12.5 to 18, The weight ratio is in the range of 1: 1 to 1:30. The blending amount of the oil phase component is in the range of not more than 300 times by weight of the total amount of the N-long-chain acylmethyl taurine salt and the water-soluble polyhydric alcohol of the present invention prepared so that the solubility parameter is 12.5-18. Is. Within the above range, a uniform emulsion composition can be obtained, and then water can be added to obtain a stable oil-in-water emulsion cosmetic.

Further, another oil-in-water emulsion cosmetic of the present invention is characterized by using a phospholipid and / or a salt thereof in combination with an N-long-chain acylmethyl taurine salt in obtaining the above-mentioned emulsion composition. is there. The mixing ratio of the N-long chain acylmethyl taurine salt and the phospholipid and / or its salt is 1: 9 to 9: 1 by weight. Solubility parameter 12.5-18
The amount of the water-soluble polyhydric alcohols of the present invention prepared so as to be in the range of 1 to 20 times by weight the total amount of the N-long-chain acylmethyl taurine salt and the phospholipid and / or its salt. Is. In this case, the blending amount of the oil phase component is the N-long chain acylmethyl taurine salt, the phospholipid and / or its salt, and the water-soluble polyvalent salt of the present invention prepared so that the solubility parameter is 12.5-18. 300 in total with alcohol
It is within the range of weight times or less. Within the above range, a uniform emulsion composition can be obtained, and then water can be added to obtain a stable oil-in-water emulsion cosmetic. The combined use of phospholipids and / or salts thereof results in a mixed surfactant system.
By lowering the HLB value, a better emulsifying property is brought about, and further, the solubility of the N-long chain acylmethyl taurine salt is increased to prevent precipitation and the like, so that the stability is further improved.

When obtaining an emulsified composition, N-long-chain acylmethyl taurine salt, the water-soluble polyhydric alcohol of the present invention,
Depending on the case, a method of adding a phospholipid and / or a salt thereof to prepare a uniform gel and then adding an oil phase component to obtain an emulsion composition may be adopted. Alternatively, these components may be added all at once. A method of mixing to obtain a uniform emulsion composition may be adopted.

In addition to the above-mentioned essential components, the oil-in-water emulsion cosmetic of the present invention further contains drugs, powders, general surfactants, pigments, fragrances, alcohols, moisturizers, preservatives, etc. which are generally used in cosmetics.
A beauty agent, an antioxidant, an ultraviolet absorber, a water-soluble polymer, etc. can be appropriately mixed.

EXAMPLES Next, the present invention will be further described with reference to examples. These do not limit the invention in any way.

Examples [1] to [2], Comparative Examples [1] to [3] As shown in Table 2 and Table 3, N-long chain acylmethyl taurine salt, water-soluble polyhydric alcohols, and oil phase components were added at 70 ° C. After the treatment with a homomixer to obtain an emulsified composition, an aqueous phase component heated to 70 ° C. was added to obtain an oil-in-water cream.

Example [3], Comparative Examples [4] to [5] As shown in Table 4, N-long-chain acylmethyl taurine salt, phospholipids and water-soluble polyhydric alcohols were treated with a homomixer at 70 ° C. to form gels. After the preparation, an oil phase component heated to 70 ° C. was added to obtain an emulsion composition, and an aqueous phase component heated to 70 ° C. was added to obtain an oil-in-water cream.

[Effects of the Invention] In order to confirm the stability of the oil-in-water emulsion cosmetic of the present invention, Comparative Examples [1] to [3] will be described for Examples [1] to [3].
Along with [5], the state after 1 month at 40 ° C was observed. The results are shown in Tables 2-4. The creams of Examples [1] to [3] were uniform emulsions and showed good stability without any change from the time of production. On the other hand, the creams of Comparative Examples [3] and [5] are separated,
In addition, the creams of Comparative Examples [1], [2], and [4] are N
-Precipitation of a solid, which is considered to be a long-chain acylmethyl taurine salt, was observed, and the stability was poor.

In order to confirm the effect of the oil-in-water emulsified cosmetic composition of the present invention that the moist feeling lasts until the next morning, in order to confirm the effect, the cream of Example [1] was compared with the cream of Comparative Example [6] (below. (Shown), the sensory test was performed.

Comparative Example [6] (Formulation) (wt%) 1. Sodium stearate 0.5 2. Glycerin 10.0 3. Liquid paraffin 20.0 4. Cetanol 5.0 5. Perfume 0.2 6.1,3-butylene glycol 10.0 7. Preservative proper amount 8. Purification Water remaining amount (manufacturing method) According to the manufacturing method of Example [1].

(Sensory test) After washing the face with a panel of 10 women, 0.05 g each of the sample cream was applied to the left and right cheeks before going to bed, and the following evaluation items were evaluated in the constant temperature room at 25 ° C the following morning. It was

(Evaluation items) 1. Good feeling on the skin 2. Softness on the skin 3. Smoothness on the skin 4. Moisture on the skin 5. Luster on the skin (Evaluation criteria) Two types of samples were compared by a five-step paired comparison method .

The results are shown in Table 5 by the number of people.

As is clear from the results in Table 5, the cream of Example [1] is superior to the cream of Comparative Example [6] in the skin effect on the next morning in terms of good skin feel and smoothness of skin. Was there. In addition, it tended to be excellent in terms of skin softness and skin smoothness.

As described above, the oil-in-water emulsion cosmetic of the present invention is
It is an oil-in-water type emulsion cosmetic that is highly stable and has a long-lasting moisturizing feeling until the next morning with excellent skin effects.

Claims (2)

[Claims] 1. A combination of N-long-chain acylmethyl taurine salt and one or more kinds selected from water-soluble polyhydric alcohols or a combination of these and water so that the solubility parameter is from 12.5 to 18. An oil-in-water type emulsion cosmetic, wherein water is further added to the emulsified composition containing the component prepared in 1. and the oil phase component. 2. A N-long-chain acylmethyl taurine salt, a phospholipid and / or a salt thereof, and a combination of one or more kinds selected from water-soluble polyhydric alcohols, or a combination thereof with water. Solubility parameter is 12.5
An oil-in-water type emulsion cosmetic, characterized in that water is further added to the emulsion composition containing the components prepared so as to have an amount of ~ 18 and an oil phase component.