JPH06165932A - Oil-in-water type emulsion - Google Patents

Abstract

PURPOSE:To provide an oil-in-water type emulsion superior in stability with the lapse of time, safety water resistance, and spreadability, and being mild without being sticky in the sensory aspect without using a surfactant. CONSTITUTION:Respectively 48-98.99wt.% of a water phase component for the total emulsion quantity, 1-50wt.% of an oil phase component, and 0.01-2.0wt.% of an emulsifier selected from higher alcohol, higher fatty acid and phospholipid are used, and Na-polyacrylate is compounded in the water phase component at least at >=0.03wt.% for the total emulsion quantity and <=0.3wt.% of the oil-in-water type emulsion is produced.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an oil-in-water emulsion, and more particularly to an oil-in-water emulsion which can be produced without using a surfactant.

[0002]

2. Description of the Related Art Some cosmetics and drugs, such as emulsions, creams and ointments, have an oil-in-water emulsion containing water phase components and oil phase components as main components. Conventionally,
When producing these oil-in-water emulsions, a surfactant such as sorbitan fatty acid ester / polyethylene glycol fatty acid ester or polyoxyethylene castor oil is usually used as an emulsifier.

However, the conventionally used surfactants have strong irritation to the skin, and many consumers are anxious. In addition, oil-in-water emulsions using these surfactants are not preferable because they are unstable over time or have a sticky feeling during use, and are not sensory preferable, and further have poor water resistance. Therefore, the amount of the surfactant used has been reduced as much as possible, and an emulsion without the surfactant has been developed.

For example, clay minerals (Japanese Patent Laid-Open Nos. 56-150007 and 57-1681) are used instead of the surfactant.
No. 2, JP-B No. 64-3529, and JP-A No. 58-1245.
35), silicone oil (JP-A-61-66527).
), Sucrose fatty acid ester and polyhydric alcohol (JP-A-55-84532), glycyrrhizin (JP-A-57-57).
No. 62214) is disclosed as an emulsifier or an emulsification aid.

[0005]

However, although the above-mentioned emulsions which do not use a surfactant have some effects, it is very difficult to obtain a stable emulsion, and there is a feeling or safety. Many of them do not fully solve the problems of surfactants, such as the above problems.

The present invention has been made from such a point of view, is excellent in stability over time, safety and water resistance without using a surfactant as an emulsifier, is not sticky in terms of sensory aspects, and has an elongation. An object is to provide a light and mild oil-in-water emulsion.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that an aqueous phase component containing a specific amount of sodium polyacrylate, an oil phase component, and an emulsification aid. It has been found that an oil-in-water emulsion having improved stability over time, safety, water resistance, and sensory performance can be obtained by blending in a ratio within a certain range, and the present invention has been completed.

That is, the present invention comprises 48 to 98.99% by weight of an aqueous phase component based on the total amount of the emulsion, and 1 to
An oil-in-water emulsion comprising 50% by weight of an oil phase component and 0.01 to 2.0% by weight of an emulsification aid, wherein the aqueous phase component contains at least sodium polyacrylate in an amount of 0. The oil-in-water emulsion is characterized in that it is contained in an amount of not less than 0.3% by weight and not more than 0.3% by weight, and the emulsification aid is selected from higher alcohols, higher fatty acids and phospholipids.

The present invention will be described in detail below. The oil-in-water emulsion of the present invention contains at least an aqueous phase component, an oil phase component, and an emulsification aid. Hereinafter, these components and the oil-in-water emulsion will be described in detail. <1> Aqueous Phase Component The aqueous phase component to be blended in the oil-in-water emulsion of the present invention contains water as a main component, and at least 0.03% by weight or more and 0.3% by weight or less based on the total amount of the emulsion. It may contain sodium polyacrylate in an amount, and may further contain a polyhydric alcohol such as glycerin, 1,3-butylene glycol and propylene glycol, and a thickener such as carboxyvinyl polymer.

The amount of sodium polyacrylate is 0.0
If it is less than 3% by weight, the hardness of the oil-in-water emulsion is low and it may separate when left for a long time, and if it is 0.3% by weight or more, it may not be preferable from the viewpoint of safety. In addition, these water phase components are blended in the range of 48 to 98.99% by weight with respect to the total amount of the oil-in-water emulsion. <2> Oil Phase Component The oil phase component to be blended in the oil-in-water emulsion of the present invention includes vegetable oils such as olive oil, corn oil and jojoba oil, animal oils such as synthetic whale wax, lanolin, beeswax and squalane.
Liquid oils such as liquid paraffin, petrolatum, and mineral oils such as silicone oils are listed as all the oils specified in the cosmetic standards, and these are the main components.

The content of these oil phase components is in the range of 1 to 50% by weight with respect to the total amount of the oil-in-water emulsion, and they are blended in one kind or in a combination of two or more kinds. If the oil phase component is less than 1% by weight, it becomes difficult to recognize as an emulsion in appearance,
If it exceeds 50% by weight, emulsification becomes difficult and an oil-in-water emulsion may not be obtained. <3> Emulsification Aid The emulsification aid blended in the oil-in-water emulsion of the present invention includes higher alcohols such as cetanol and stearyl alcohol, higher fatty acids such as myristic acid, stearic acid and palmitic acid, and phospholipids such as lecithin. Etc.

These emulsification aids are blended in the range of 0.01 to 2.0% by weight with respect to the total amount of the oil-in-water emulsion, and are blended in one kind or in a combination of two or more kinds. If the emulsification aid is less than 0.01% by weight, it is difficult to form an emulsion, and if it exceeds 2.0% by weight, the structure formation of the outer phase proceeds after being left for a long time, and a remarkable increase in hardness is observed. It may be impossible to remove the cream by hand. <4> Oil-in-Water Emulsion of the Present Invention As the components of the oil-in-water emulsion of the present invention, other than the above-mentioned components, one or two components used in ordinary general cosmetics may be used. It is possible to mix in combination of two or more kinds. Examples of such components include fragrances, dyes, preservatives, antioxidants, anti-inflammatory agents, ultraviolet absorbers, ultraviolet reflectors and pH adjusters.
Further, if necessary, various medicinal components such as hyaluronic acid, allantoin, vitamins, placenta extract and the like can be added.

The oil-in-water emulsion of the present invention is a normal oil-in-water emulsion in which the oil phase component heated and dissolved in advance and the emulsification aid are gradually added to the heated water phase component to disperse and emulsify with a stirrer. It is manufactured by the same method as.

[0014]

EXAMPLES Examples of the present invention will be described below.

[0015]

Examples 1 to 6 Cream As an oil-in-water emulsion of the present invention, examples in cream cosmetics will be described. <Production Method> The creams of Examples 1 to 6 and the oil-in-water emulsions of Comparative Examples 2 to 6 in which the blending amounts of the respective main components deviated from the formulation of the emulsion of the present invention were produced. Also, the cream of Comparative Example 1 was produced as a conventional cream containing a surfactant.

Using each of the components shown in Table 1, the oil phase component and the emulsification aid, which had been heated and dissolved in advance, were gradually added to the heated aqueous phase component and dispersed and emulsified with a stirrer to produce a cream. .

[0017]

[Table 1] In addition, (-) in Table 1 indicates that the test was not performed. <Evaluation> The oil-in-water creams of the above Examples and Comparative Examples were evaluated by the following methods for actual use test regarding safety and usability, water resistance, stability test, emulsified state, and appearance. (1) Safety The creams of Examples 1 and 2 and Comparative Examples 1 and 2 were used in the mornings and evenings for 50 weeks for 50 female panelists aged 24 to 58 instead of the creams normally used. The subject's awareness and the skin condition before and after use were objectively evaluated.

The evaluation was carried out by comprehensively judging items such as tingling and tingling, redness, squirting rash, and dryness. The number of people was shown as a result when these symptoms were expressed as positive. (2) Usability In the same manner as described above, 50 female panelists were asked to use the creams of Example 1 and Comparative Example 1 for 2 weeks each in the morning and evening instead of the cream that they usually use, and sensory evaluation I went.

The evaluation was made by comprehensively judging items such as spread, oiliness, and stickiness according to the following criteria, and 50
The average value of the names was expressed as the result. Good: 10 points Neither can be said: 5 points Poor: 0 points (3) Water resistance For 20 female panelists, 0.1 g of each Example and Comparative Example sample was uniformly applied to the forearm, and then showered. After being applied to the coated part for 5 minutes and lightly wiped off with a towel, it was sensory evaluated visually with the following criteria.

Remaining on the skin: ○ Runoff: × (4) Stability 10 samples each of the oil-in-water creams of all Examples and Comparative Examples were placed in a thermostatic chamber at 20 ° C, 40 ° C and 50 ° C. After standing for 3 months, hardness and separation were visually observed and evaluated according to the following criteria.

Good: ○ Separation or hardness increase: × (5) Emulsified state With respect to the oil-in-water creams of all Examples and Comparative Examples, the quality of the emulsified state immediately after preparation was evaluated using the naked eye and a microscope.

Good: ○ Cannot be emulsified: × The results of the above evaluations are shown in the lower column of Table 1. In addition, as a result of the safety test, the cream of Comparative Example 2 caused papules to occur 5 times.
It was seen in 8 out of 0 people. On the other hand, in the cream of the example,
The incidence of papules was 1 in 50.

From the above results, the oil-in-water cream of the present invention has excellent emulsified state, good appearance, safety, light elongation, no stickiness, and other excellent sensory aspects, and also has water resistance and stability over time. It turns out that it is also excellent.

[0024]

Example 7 Emulsion Next, an example of emulsion as an oil-in-water emulsion of the present invention will be described.

The aqueous phase component shown in Table 2A is heated, and the component B which has been heated and dissolved in advance is gradually added thereto, and dispersed and emulsified by a stirrer.

[0026]

[Table 2]

[0027]

The oil-in-water emulsion according to the present invention comprises
It has excellent stability over time, water resistance, and sensory properties, and because it does not use a surfactant, it is also highly safe, and is expected to be applied to cosmetics and pharmaceuticals.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinya Okabe 27 Takashimadai, Kanagawa-ku, Yokohama, Kanagawa 1 Polar Chemical Industry Co., Ltd. Yokohama Laboratory

Claims (1)

[Claims] 1. A total of 48 to 9 with respect to the total amount of emulsion.
An oil-in-water emulsion comprising 8.99% by weight of an aqueous phase component, 1 to 50% by weight of an oil phase component, and 0.01 to 2.0% by weight of an emulsification aid, wherein the aqueous phase component is At least sodium polyacrylate is contained in an amount of 0.03% by weight or more and not more than 0.3% by weight with respect to the total amount of the emulsion, and the emulsification aid is a higher alcohol, a higher fatty acid,
An oil-in-water emulsion characterized by being selected from phospholipids.