JP2003253144A - Oil-in-water type emulsified composition and method for manufacturing emulsified composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil-in-water type emulsified composition exhibiting excellent stability with time without using a surfactant. <P>SOLUTION: The oil-in-water type emulsified composition comprises at least one oily component selected from the group consisting of fatty acids and higher alcohols and at least one polymer soluble in the oily component. The method for manufacturing the emulsified composition comprises forming a gel from at least one oily component selected from the group consisting of fatty acids and higher alcohols, at least one polymer soluble in the oily component and a polyhydric alcohol having a hydricity of three or higher or an aqueous solution of the polyhydric alcohol and subsequently converting the gel into an oil-in- water-type emulsified composition. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an oil-in-water emulsion composition and a method for producing the same.

[0002]

2. Description of the Related Art Conventional oil-in-water emulsion compositions have been produced by emulsification using surfactants and water-soluble polymers such as hydroxyethyl cellulose, sodium carboxymethyl cellulose, pullulan and pectin. In recent years, Fragrance Journal, 26, 8, 79 (1
998), polyelectrolyte complex (anionic polymer and cationic polymer), Fragrance Journal, 26, 8,
42 (1998) and the like, a production method using an acrylic acid / alkyl methacrylate copolymer is described.

However, such a conventional oil-in-water emulsion composition has the following problems. When a surfactant is used, there is a bad influence on the feeling of use such as stickiness due to the surfactant, and there is also a problem in safety because the surfactant may be percutaneously absorbed. When an oil-in-water emulsion composition emulsified with a surfactant is applied to a cosmetic composition, the surfactant remains on the skin and is easily re-emulsified by sweat or moisture, resulting in different makeup. There was also the problem of becoming.

Although various studies have been made on the emulsification with a water-soluble polymer, conventional emulsification has not been sufficient in terms of emulsion stability and usability.

In the case of emulsification using an acrylic acid / alkyl methacrylate copolymer, the emulsified particles are large and it is difficult to maintain stability over time. Further, since it is stabilized with a polymer gel, it has a unique feeling of use and is not widely applied.

Various emulsification systems using other polymers have been studied, but the ones using a polymer electrolyte complex are still insufficient in terms of emulsion stability.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide an oil-in-water emulsion composition which does not use a surfactant and has good stability over time, and a method for producing the same.

[0008]

The present invention has been made by paying attention to such conventional problems. That is,
The present invention is an oil-in-water type characterized by containing one or more oils selected from the group consisting of fatty acids and higher alcohols, and one or more polymers soluble in the oils, and containing no surfactant. Emulsion composition, the oil-soluble polymer is a polyvinylpyrrolidone homopolymer, or the oil-in-water emulsion composition is a copolymer containing vinylpyrrolidone, further, containing a polyhydric alcohol of trihydric or more Oil-in-water emulsion composition, further, the oil-in-water emulsion composition containing a water-soluble polymer insoluble in the oil, and an oil containing one or more selected from the group consisting of fatty acids and higher alcohols, the oil A water-soluble polymer and a polyhydric alcohol having a valence of 3 or more or an aqueous solution of a polyhydric alcohol having a valence of 3 or more are used to form a gel, and then an oil-in-water emulsion composition is prepared. Process for the preparation of an emulsion composition, wherein the.

The oil-in-water emulsion composition of the present invention is characterized in that it contains no surfactant and has good stability over time.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The oil-in-water emulsion composition of the present invention comprises
It contains one or more oils selected from the group consisting of fatty acids and higher alcohols, and one or more polymers soluble in the oils.

The oil-in-water emulsion composition has an outer water phase and an inner oil phase, the oil component forms an inner oil phase, and the polymer soluble in the oil component acts as an emulsifier.

It is preferable that the fatty acid has 6 or more carbon atoms and is liquid at room temperature (25 ° C.). When the carbon number is less than 6, lipophilicity is insufficient. When the lipophilicity of the fatty acid forming the oil phase is insufficient, the polymer soluble in the oil becomes difficult to orient in the oil phase, and the action as an emulsifier decreases, so the stability of the emulsion composition Tends to decrease. Further, when it is not liquid at room temperature, the compatibility tends to be poor when an oil component other than the above-mentioned oil component, particularly a silicone oil, is blended as a component forming the oil phase. However, the compatibility can be improved by using it together with a liquid oil such as a liquid fatty acid, a liquid higher alcohol and a liquid ester oil. As the fatty acid, linear fatty acids such as caproic acid, caprylic acid and stearyl acid; branched fatty acids such as isopalmitic acid and isostearic acid; unsaturated fatty acids such as oleic acid, myristoleic acid and palmitoleic acid can be used. .

Higher alcohols have 6 or more carbon atoms and are at room temperature (2
A liquid at 5 ° C.) is preferable. When the carbon number is less than 6, lipophilicity is insufficient. When the lipophilicity of the higher alcohol forming the oil phase is insufficient, the polymer soluble in the oil becomes difficult to be oriented in the oil phase, and the action as an emulsifier decreases, so that the stability of the emulsion composition is improved. Sex tends to decrease. Further, when it is not liquid at room temperature, the compatibility tends to be poor when an oil component other than the above-mentioned oil component, particularly a silicone oil, is blended as a component forming the oil phase. However, the compatibility can be improved by using it together with a liquid oil such as a liquid fatty acid, a liquid higher alcohol and a liquid ester oil. As a higher alcohol,
Linear higher alcohols such as octanol and decanol;
Branched higher alcohols such as isostearyl alcohol and octyldodecanol; unsaturated higher alcohols such as oleyl alcohol can be used.

The oil content is preferably 0.1% by weight or more, more preferably 1% by weight or more. 0.1
If it is less than wt%, a good emulsion composition cannot be obtained. There is no particular upper limit to the blending amount of the oil component, and it can be blended in consideration of usability and the like.

Examples of the polymer soluble in oil include polyvinylpyrrolidone, vinylpyrrolidone / vinyl acetate copolymer, polyvinylcaprolactam, vinylpyrrolidone / vinylcaprolactam copolymer, and poly-N-vinylacetamide. And vinylpyrrolidone / vinyl acetate copolymer are particularly preferred.

As the molecular weight of the oil-soluble polymer, those having a weight average molecular weight of 1,000 to 15,000,000, especially 5,000 to 500,000 are used. As the polymer soluble in oil, commercially available products can be used. If the molecular weight is too low, it may be percutaneously absorbed, so the benefits of using a surfactant may be lost.If the molecular weight is too high, sliminess and stickiness may occur, resulting in poor usability. . The vinylpyrrolidone / vinyl acetate copolymer may contain 10 to 90 mol% of vinyl acetate. Regarding the vinylpyrrolidone / vinylcaprolactam copolymer, since both polyvinylpyrrolidone and polyvinylcaprolactam can be used alone as a polymer soluble in the oil, the composition is not particularly limited, but, for example, in the copolymer, , 1 caprolactam vinyl
˜99 mol%.

The vinylpyrrolidone / vinyl acetate copolymer and vinylpyrrolidone / vinylcaprolactam copolymer used as the oil-soluble polymer are used as a random copolymer or a block copolymer.

The oil-soluble polymer is preferably 0.1 to 10% by weight, more preferably 0.2 to 2% by weight.
Be compounded. If it is less than 0.1% by weight, the effect as an emulsifier is insufficient, and if it exceeds 10% by weight, the viscosity of the system becomes too high and the usability is deteriorated, and sliminess due to a polymer is felt, which is not preferable. The oil-soluble polymer may be added to either the inner oil phase, the outer water phase, or both, but the emulsified state is better when added to the inner oil phase.

The oil-in-water emulsion composition of the present invention contains no surfactant.

The oil-in-water emulsion composition of the present invention may further contain a trihydric or higher polyhydric alcohol. It is possible to obtain a good emulsion even when not blending a trihydric or higher alcohol, but after forming a gel with oil and a trihydric or higher polyhydric alcohol, by dispersing in a water phase, a better emulsification A composition can be obtained. Therefore, by adding a polyhydric alcohol having a valence of 3 or more, the emulsified state and stability over time are further improved.

Examples of trihydric or higher polyhydric alcohols include glycerin and sorbitol. As the trihydric or higher polyhydric alcohol, a high molecular weight substance such as polyglycerin may be used, and the upper limit of the valency is not particularly limited. Alcohols less than trivalent cannot form a gel with oil. The trihydric or higher polyhydric alcohol is preferably 1 to 20% by weight,
More preferably, 3 to 15% by weight is blended. If it is less than 1% by weight, a gel cannot be formed, and if it exceeds 20% by weight, a sticky feeling is obtained. The trihydric or higher polyhydric alcohol may be added as it is or as an aqueous solution. The concentration of the polyhydric alcohol in the aqueous solution is not particularly limited because it depends on the type of polyhydric alcohol,
It is preferable that the concentration is as high as possible.

The oil-in-water emulsion composition of the present invention further comprises
A water-soluble polymer insoluble in the oil may be included.

As the water-soluble polymer insoluble in the oil,
Examples thereof include carboxyvinyl polymer, sodium acrylate, xanthan gum, sodium alginate, sodium carboxymethyl cellulose and hydroxyethyl cellulose. The addition of the water-soluble polymer insoluble in the oil facilitates emulsification, and the thickening of the outer water phase can improve the stability over time and adjust the feeling of use. The oil-insoluble water-soluble polymer is preferably 0.05 to 10% by weight, more preferably 0.1.
-1% by weight is blended. If it exceeds 10% by weight,
Also, stickiness and the like may occur, resulting in poor feeling in use.

The oil-in-water emulsion composition of the present invention may contain an oil component other than the above-mentioned oil component as a component forming the oil phase. As the oil component other than the oil component, any of solid, paste, and liquid forms at room temperature can be blended, and hydrocarbon-based polar oil, non-polar oil, silicone-based oil and the like can be used. For example, glycerin trioctanoate, liquid paraffin, dimethyl silicone, etc. can be used.

The oil-in-water emulsion composition of the present invention contains at least one oil component selected from the group consisting of fatty acids and higher alcohols, a polymer soluble in the oil component, a trihydric or higher polyhydric alcohol, and In addition to water-soluble polymers that are insoluble in oil, moisturizers, germicides, preservatives, antioxidants, pH adjusters,
It may contain an ultraviolet absorber, a powder such as titanium oxide or barium oxide, a coloring agent such as iron oxide, or the like.

The oil-in-water emulsion composition of the present invention is prepared by heating the oil phase and the water phase if necessary and homogenizing them, and then mixing and stirring them using a disper, a homomixer and the like. . For example, it is prepared by dissolving an oil-soluble polymer in oil and then adding it to water. When an oil-soluble polymer such as polyvinylpyrrolidone is dissolved in the oil, heating is usually required, but a solvent that dissolves the oil-soluble polymer such as polyvinylpyrrolidone, for example, ethanol is used. Therefore, the operation can be simplified.

When the oil-in-water emulsion composition of the present invention contains a trihydric or higher polyhydric alcohol, for example, a trihydric or higher polyhydric alcohol and an oil-soluble polymer are dissolved in the oil to form a gel. After forming, the emulsion composition can be prepared by adding water.

The oil-in-water emulsion composition of the present invention is effectively used as an oil-in-water emulsion composition containing no surfactant and having good stability over time. The oil-in-water emulsion composition of the present invention can be applied to, for example, emulsions, moisturizing creams, foundations, sunscreen creams, emulsified cosmetics such as hair creams, and emulsified pharmaceuticals such as cream preparations.

[0029]

EXAMPLES Examples 1 to 7 and Comparative Examples 1 to 2 In Table 1, isostearic acid, oleic acid, stearic acid and octyldodecanol are oil components in phase A,
PVP is a polymer soluble in oil, glycerin is a polyhydric alcohol, and ethanol is a solvent that dissolves PVP. In phase B, glycerin trioctanoate, liquid paraffin and dimethyl silicone correspond to the other components forming the oil phase. In phase C, glycerin corresponds to polyhydric alcohol, carboxymethyl cellulose and xanthan gum correspond to oil-insoluble water-soluble polymer. In the D phase, carboxyvinyl polymer corresponds to a water-soluble polymer insoluble in oil, and triethanolamine corresponds to a neutralizing agent (pH adjusting agent).

Phase A having the blending composition (weight ratio) shown in Table 1 was heated and stirred as necessary to make it uniform, and phase B previously dissolved was added and emulsified by disper stirring. After that, the phase C was added and homogenized to carry out the emulsification, and if necessary, the phase D was further added to obtain a final emulsion composition.

The stability of the prepared emulsion composition was evaluated by the following evaluation methods and evaluation criteria.

<Stability Evaluation Method> The prepared emulsified composition was filled in a sample bottle, allowed to stand at 50 ° C. for 1 month, and then visually observed.

<Stability Evaluation Criteria> A: No separation is observed. ◯: Almost no separation is observed. Δ: Slight separation is observed. X: Clear separation is recognized.

The results are shown in Table 1.

[0035]

[Table 1]

[0036]

INDUSTRIAL APPLICABILITY According to the present invention, an oil-in-water emulsion composition having good stability over time can be provided by incorporating a polymer soluble in oil, without using a surfactant. .

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08J 3/03 CER C08K 5/05 3/075 CER 5/09 C08K 5/05 C08L 39/06 5/09 C08J 3/03 CER C08L 39/06 F term (reference) 4C083 AC022 AC072 AC102 AC111 AC122 AC242 AC252 AC262 AC351 AC352 AC422 AC542 AD071 AD072 AD152 AD272 AD352 CC05 DD31 EE01 FF05 4F070 AA38 AA71 AB11 AB12 AC36 AC40 CB12 CG02 CA11 CA12 CA12 CA11 CA12 CA12 CA11 AA01 AB03X AB05X AB12X AB16X AB17X AB28X AB35X BB08 CA03 DA02 FA01 4J002 AB032 AB052 BG012 BJ001 EC056 EC066 EF016 EF056 FD206 HA04 HA06

Claims (5)

[Claims] 1. An oil-in-water containing one or more oils selected from the group consisting of fatty acids and higher alcohols, and one or more polymers soluble in the oils and containing no surfactant. Emulsion composition. 2. The oil-in-water emulsion composition according to claim 1, wherein the polymer soluble in oil is a polyvinylpyrrolidone homopolymer or a copolymer containing vinylpyrrolidone. 3. The oil-in-water emulsion composition according to claim 1, which further comprises a polyhydric alcohol having a valence of 3 or more. 4. The oil-in-water emulsion composition according to claim 1, further comprising a water-soluble polymer insoluble in the oil. 5. A gel containing an oil containing at least one selected from the group consisting of fatty acids and higher alcohols, a polymer soluble in the oil, and a polyhydric alcohol having a valence of 3 or more or an aqueous solution of a polyhydric alcohol having a valence of 3 or more. And then forming an oil-in-water type emulsion composition.