CN106806158B

CN106806158B - Oil-in-water emulsion composition and preparation method thereof

Info

Publication number: CN106806158B
Application number: CN201610979753.0A
Authority: CN
Inventors: 孟蒙; 古川原智美; 高桥繁郎; 魏洁; 王颖
Original assignee: Shiseido Co Ltd
Current assignee: Shiseido Co Ltd
Priority date: 2016-11-08
Filing date: 2016-11-08
Publication date: 2020-04-14
Anticipated expiration: 2036-11-08
Also published as: CN106806158A

Abstract

The present invention relates to an oil-in-water emulsion composition and a method for producing the same, the composition comprising the following essential components: (A) a volatile silicone oil; (B) a polymer compound having an emulsifying ability; (C) a nonionic surfactant having an HLB value of 11 or more, wherein the content of the component (A) is 20% by mass or more, the content of the component (B) is 0.35% by mass or less, and the content of the component (C) is 2% by mass or less, and the composition can impart improved or enhanced smooth feeling and absorption feeling to the human body when used, and also has improved or enhanced and sustained refreshing feeling after use.

Description

Oil-in-water emulsion composition and preparation method thereof

Technical Field

The invention belongs to the field of daily-use chemical industry, particularly relates to the field of cosmetics, and particularly relates to an oil-in-water emulsion composition, and a preparation method and a product thereof.

Background

Oil-in-water compositions are a common source in the cosmetics industry for the preparation of products such as lotions, tonic water, essences and toilet water. Wherein the oil phase component exists in the water-based system uniformly and stably under the action of the surfactant. Such systems may be in a transparent, translucent or opaque state, depending on the size of the oil phase droplets dispersed in the dispersion system. In addition, means such as an applied shear force or ultrasonic waves may be used to assist in achieving a stable balance between the continuous phase and the oil phase in the dispersion system.

In the common oil-in-water emulsion and microemulsion, the required service performance, such as various body feeling or beautifying and skin care effects, is obtained by adding proper functional ingredients or active ingredients.

People with oily skin generally seek a refreshing feeling when using skin care products.

Emulsion skin care products on the market are mostly emulsion compositions of an oil-in-water system or a water-in-oil system. The water-in-oil emulsion composition is greasy and heavy when being applied on the skin, and does not meet the requirements of people with oily skin. Thus, products using oil-in-water systems are preferred for this skin population. In an emulsion composition of an oil-in-water system, the relative content of the oil phase as a dispersed phase is small in order to obtain a stable system, and generally more refreshing feeling can be given to people than a water-in-oil type skin care product. Generally, in the oil-in-water type emulsion skin care products, the refreshing feeling is achieved by adding a certain amount of ethanol, and the skin heat is taken away by the rapid evaporation of the ethanol after the skin is coated. However, such skin care products containing an alcohol component have become less popular with consumers in terms of odor and feeling of use in recent years.

At present, volatile silicone oils are also widely used as oil phase components in cosmetics. The silicone oil has good chemical stability, temperature resistance, hydrophobicity, lubricity and storage stability, has low surface tension, no irritation, low toxicity and no allergy, and can be compatible with common cosmetics. In particular, volatile silicone oils impart quick-drying, smooth, anti-fouling and good gloss properties to cosmetics. As a cosmetic carrier, it dissipates quickly to enable the other cosmetic components to form a uniformly distributed film. In addition, the greasy feeling of the volatile silicone oil to the human body can be further reduced compared with other oil substances.

On the other hand, consumers are pursuing a smooth feeling during application of skin care products, and in the conventional oil-in-water system, it is actually difficult to obtain a satisfactory smooth feeling during application because the amount of oil added is relatively small.

In document 1, although it is described that volatile silicone oil can be used in cosmetics, the amount of volatile silicone oil used is relatively small in various emulsion formulations disclosed therein. In particular, the recommended amount for volatile silicone oils in the emulsion is not more than 1%. Therefore, the effect of improving the smoothness, the refreshing feeling, and the like of the product is not considered to be sufficient.

In document 2, a single-phase microemulsion composition is disclosed which is an oil-in-water type external emulsion in which the amount of an oil component in the single-phase microemulsion may be 10 to 40%, however, the use of volatile silicone oil is not disclosed.

Document 3 discloses a skin care oil-in-water product which has good application uniformity, can exist stably, and has no sticky feeling, and which may contain 5 to 30% of a volatile silicone oil. However, the presence of a large amount of solid phase in the product results in a product which is actually in the form of a paste-like system, and the high solid content brings about a relatively high viscosity upon application, thereby partially inhibiting a refreshing feeling.

Document 4 discloses a transparent oil-in-water nanoemulsion in which an oil phase is stably dispersed in a nano-scale size by using an ionic surfactant and a nonionic surfactant in combination. Although the amount of the disclosed oily component exceeds 20%, it is not actually more than 7% of the disclosed volatile silicone oil.

Therefore, at present, in cosmetics, especially skin care type emulsion cosmetics, there is still a need for further improvement or improvement in achieving better refreshing feeling and smooth feeling.

Cited document 1: "use of silicone oil in cosmetics (below)", Huyan, Fine and specialty Chemicals, 1985-07-21

Cited document 2: WO2005/065630A1

Cited document 3: CN1448122A

Cited document 4: CN101502478A

Disclosure of Invention

Problems to be solved by the invention

In view of the above-mentioned drawbacks of the prior art, the present invention provides an oil-in-water emulsion composition which, when used, can give an improved or enhanced smooth (soft) feel and absorption feel to the human body, and which, after used, can give an improved or enhanced and sustained refreshing feel to the human body.

Further, another object of the present invention is to provide a method for producing a stable oil-in-water emulsion composition, and a cosmetic comprising the same, which includes a skin-care or hair-care cosmetic.

Means for solving the problems

The present invention solves the technical problem faced by the following means:

the present invention firstly provides an oil-in-water emulsion composition comprising the following essential components:

(A) a volatile silicone oil; (B) a polymer compound having an emulsifying ability;

(C) a nonionic surfactant having an HLB value of 11 or more,

the content of the component (A) is 20 mass% or more, the content of the component (B) is 0.35 mass% or less, and the content of the component (C) is 2 mass% or less.

In the above composition of the present invention, the component (B) is a high molecular compound having an emulsifying ability, which is one or a mixture of two or more selected from (meth) acrylic acids, C10-C30 alkyl ester polymers of (meth) acrylic acid, and copolymers thereof.

In the above composition of the present invention, the component (B) is a copolymer of a (meth) acrylic monomer and a C10-C30 alkyl (meth) acrylate monomer.

In the above composition of the present invention, the HLB value of the nonionic surfactant of the component (C) is 13 to 15.

In the above composition of the present invention, the volatile silicone oil of component (a) includes linear polydimethylsiloxane.

In the above composition of the present invention, the amount of the component (a) is less than 35% by mass, the amount of the component (B) is more than 0.04% by mass, and the amount of the component (C) is 0.2% by mass or more.

In the above composition of the present invention, the amount of the component (A) is 20 to 30% by mass, the amount of the component (B) is 0.05 to 0.2% by mass, and the amount of the component (C) is 0.2 to 1.5% by mass.

The present invention additionally provides a process for the preparation of a composition according to the above, comprising the steps of mixing components (a), (B) and (C) with an aqueous phase and of stabilizing the mixture obtained to obtain a stable emulsion system.

Furthermore, the present invention also provides a cosmetic product comprising the composition according to the invention above.

The cosmetic is a skin care cosmetic or a hair care cosmetic.

ADVANTAGEOUS EFFECTS OF INVENTION

The oil-in-water emulsion composition provided by the invention has the following excellent effects when used as a cosmetic product by a human body:

(1) when used by human body, the product can be applied on skin, and has improved lubrication and absorption;

(2) after use, has improved, sustained refreshing feeling, and no greasy feeling;

(3) the oil-in-water emulsion composition can exist stably in a wider range of environmental temperature for a longer time.

(4) The oil-in-water emulsion composition of the present invention is characterized by simple preparation as a cosmetic raw material or ingredient, i.e., excellent body feeling and good economical efficiency.

Detailed Description

The oil-in-water emulsion composition provided by the invention comprises three essential components, namely (A) volatile silicone oil, (B) a high molecular compound with emulsifying capacity and (C) a nonionic surfactant with the HLB value of more than 11.

The volatile silicone oil (a) is used in the oil-in-water emulsion composition of the present invention in a relatively high content, for example, in an amount of 20% by mass or more. Therefore, on the one hand, when a cosmetic preparation comprising the oil-in-water emulsion composition of the present invention is used by a human body, an improved feeling of lubrication can be obtained; on the other hand, the volatile silicone oil (A) can also completely or partially replace ethanol quick-drying components used in conventional cosmetics, thereby not only bringing continuous and improved refreshing feeling, but also avoiding uncomfortable feeling brought to human body or skin allergy caused by the odor of the ethanol components in the prior products.

Further, although the oil-in-water type emulsion composition provided in the present invention has a high content of (a) volatile silicone oil, the emulsion system can be maintained in a stable continuous phase and dispersed phase because of the combined use of (B) a high molecular compound having emulsifying ability and (C) a nonionic surfactant having an HLB value of 11 or more, which are present in a certain amount at the same time. Wherein (B) a high molecular compound having emulsifying ability, typically represented by a high molecular emulsifier or thickener of (meth) acrylic acid or (meth) acrylate, is capable of producing a good synergistic effect with (C) a nonionic surfactant having an HLB value of 11 or more to stabilize an oil phase in an emulsion system in the form of stable oil droplets.

Hereinafter, each component used in the present invention will be described in detail, and it should be noted that the following "percent" or "%" refers to mass percent or "% by mass" unless otherwise specified.

(A) volatile Silicone oil

The low surface tension and suitable viscosity of the silicone oil can make other components in the cosmetic easily spread on the skin to form a film, and the film does not have sticky feeling. The volatile silicone oil is a silicone oil of relatively low molecular weight, which is a volatile, low viscosity silicone oil that is highly compatible with many cosmetic ingredients and readily soluble in most cosmetic solvents, and is odorless, non-toxic, transparent, non-sticky, and non-irritating. As base oils or temporary carriers, they have good dispersibility and are easy to remove, leave no residual liquid after evaporation, and at the same time, reduce the surface tension and facilitate homogenization. Further, since they have a low heat of vaporization, they give no cold feeling when volatilized.

The volatile silicone oil generally used includes low molecular weight polydimethylsiloxane-type silicone oil having the following structural formula (1) and the like.

Typical volatile silicone oils of this type have hexamethyldisiloxane and the like represented by the following structure (2).

The molecular weight of the low molecular weight polydimethylsiloxane is not particularly limited, and the low molecular weight polydimethylsiloxane has the function of rapid evaporation at normal temperature. However, in the present invention, the low molecular weight polydimethylsiloxane-based silicone oil is preferably a low molecular weight polydimethylsiloxane-based silicone oil having a structure represented by the above formula (1), and n in the structure is 0 to 3, more preferably n is 2, from the viewpoint of the refreshing effect in human body feeling.

In addition, as the low-viscosity volatile silicone oil which can be selected for use in the present invention, in addition to the above-mentioned linear polydimethylsiloxane, there can be also included silicone oils having a cyclic methyl group, such as octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5). However, in some extreme cases, these low molecular weight cyclic siloxanes are not preferred as low viscosity volatile silicone oils in the present invention due to the impact on the potential burden that the environment may impose.

The amount of the volatile silicone oil (a) used in the present invention is required to be small, for example, usually less than 10% in the case of conventional cosmetics, for example, in the case of an oil-in-water type system, because a stable emulsion system is required, and a certain amount of an ethanol component is generally used as a main source of refreshing feeling. Meanwhile, although the use of a volatile silicone oil component of up to about 20% is also mentioned in the existing cosmetics such as cream-like cosmetics having a high solid content, the coating property is not desirable due to the high viscosity of the product itself. Therefore, this also suppresses the feeling of lubrication or refreshing feeling of the human body. In addition, due to the higher solids content of the paste, the effect of the increased oil phase content (relative to the aqueous phase) on the stability of the final product system is also significantly reduced.

In the present invention, the amount of the volatile silicone oil (a) is 20% or more based on the whole oil-in-water emulsion composition in order to improve or improve the feeling of body refreshing and to enhance the lubricating effect of the cosmetic product. Further, the amount of the (a) volatile silicone oil is preferably 20% or more and less than 35%, more preferably 20% to 30%, and most preferably 20% to 25%, from the viewpoint of obtaining a stable emulsified system. Namely, the relatively high content of the (A) volatile silicone oil in the invention can obtain a relatively stable emulsion system, and can be quickly coated on a human body along with the oil-in-water type emulsion, and the emulsion is retained on the surfaces of skin, hair and the like of the human body, so that the human body can continuously have a refreshing feeling while feeling relatively good smoothness through continuous evaporation.

In addition, as the volatile silicone oil (a) used in the present invention, one kind of the above-mentioned various substances having specific structures may be used alone, or several kinds may be used in combination.

It should be noted that the component (a) in the present invention may be a main component of the volatile component, and needless to say, a volatile alcohol or the like may be used in addition thereto without impairing the technical effects of the present invention, except that these components may not be a main functional component.

(B) Polymer Compound having emulsification ability

In the present invention, the polymer compound (B) having emulsifying ability is one or a mixture of two or more selected from (meth) acrylic acids, polymers of (meth) acrylic esters, or copolymers of both. (B) The polymer compound having an emulsifying ability plays a role in thickening and stabilizing the oil-in-water emulsion composition system of the present invention.

Generally, in an oil-in-water emulsion system, an emulsifier with a certain HLB value is used, when a mixed system containing oil and water is sheared by mechanical shearing force, dispersed oil droplets are formed, and at the same time, the emulsifier is quickly distributed on the surfaces of the oil droplets to form an oil-in-water emulsion system with certain stability. However, such oil-in-water emulsion systems are actually lacking in long-term stability. When the application is stopped by mechanical shear forces, the small molecules of the emulsifier will to some extent migrate freely and leave the surface of the oil droplets, exposing a part of the oil-water surface to which no emulsifier is adsorbed. Thus, when such oil droplets come into contact with other oil droplets, aggregation of the oil phase occurs to form a larger liquid, thereby destabilizing the emulsion system.

Therefore, in such a system, it is necessary to stabilize oil droplets using (B) a polymer compound having an emulsifying ability. In the present invention, one or a mixture of two or more of (meth) acrylic acid type, (meth) acrylate type polymer or (meth) acrylic acid- (meth) acrylate copolymer is used as an additional emulsifier or thickener ingredient for stabilizing oil droplets.

Typically, as the (B) high molecular compound having an emulsifying ability, the present invention may use a polymer (including a homopolymer or various copolymers) having a long chain alkyl (meth) acrylate as an emulsifier component. Of course, such a copolymer may be a copolymer or a crosslinked product of a long chain alkyl (meth) acrylate and a (meth) acrylic monomer. The polymer compound having such a structure can stabilize an oil-in-water system.

As the long chain alkyl ester, there may be mentioned alcohols derived from C10-C30 alkyl groups. The obtained macromolecular compound enables hydrophilic carboxyl in a molecular chain to face a water phase and an oleophilic chain segment to face an oil phase to form a stable protective layer for the oil phase, and effectively provides stability for an oil-in-water emulsion system.

The polymer compound having emulsifying ability (B) in the present invention is preferably Pemulen^TMTR-2 (sold by The Lubrizol Corporation,29400Lakeland Boulevard Wickliffe, Ohio, U.S. A).

The inventors of the present invention have surprisingly found that, in order to achieve excellent stabilization of oil droplets in an oil-in-water system having a high content of (a) volatile silicone oil, when (B) a high molecular compound having an emulsifying ability of the present invention is used in combination with a nonionic surfactant having an HLB value of 11 or more, an oil-in-water emulsion system having excellent stability can be obtained relatively easily. It should be noted that the stability described herein refers to the stability of the continuous phase-dispersed phase achieved over a longer standing time and a wider temperature range.

In the oil-in-water emulsion composition of the present invention, the amount of the high molecular compound (B) having an emulsifying ability may be more than 0 and 0.35% or less, preferably, more than 0.04%, and may be 0.05% to 0.2%, more preferably 0.08% to 0.15%, and most preferably 0.1% to 0.12%. The lower limit of the amount of the component (B) is not limited in principle, but if the amount is too small, for example, 0.04% or less, in some extreme cases, there is a fear that a stable emulsion system cannot be formed, and if the amount is too large, the viscosity of the emulsion system becomes too high, which affects the production efficiency at the time of production, for example, at the time of filling.

Nonionic surfactant having HLB value of 11 or more

The nonionic surfactant used in the present invention is not particularly limited as long as it has an HLB value of 11 or more. Micellar dissolution in aqueous solvents is preferred. Examples of the nonionic surfactant used in the present invention include polyoxyethylene fatty acid glycerides, polyoxyethylene-polymethylsiloxane copolymers, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene alkyl ethers, maltitol hydroxyalkylalkyl ethers, alkylated polysaccharides, alkyl glycosides, sucrose fatty acid esters, and the like.

When the HLB value of the nonionic surfactant of the present invention is controlled to 11 or more, as described above, a good synergistic effect can be produced with (B) the high molecular compound having an emulsifying ability, and thus a better stabilizing effect on an oil phase can be obtained. Particularly, in the case of the volatile silicone oil of the present invention, which is used in a relatively high amount, an excellent stabilizing effect can be obtained.

In the present invention, the nonionic surfactant is preferably a substance having an HLB value of 13 to 15, and most preferably a substance having an HLB value of 13, typically PEG-20 glyceryl isostearate.

In the oil-in-water emulsion composition of the present invention, (C) the nonionic surfactant having an HLB value of 11 or more may be used in an amount of more than 0 and 2% or less, preferably, 0.2% to 1.5%, or more preferably, 0.3% to 1.2%, and most preferably, 0.5% to 1%. There is no limit in principle to the lower limit of the amount of the (C) component. However, if the amount is too small, for example, less than 0.2%, in some extreme cases, a stable emulsion system may not be formed, and if the amount is too large, it is not preferable for safe production and use.

< water >)

It goes without saying that the continuous phase in the oil-in-water system of the present invention is an aqueous phase, and the water of the present invention may be distilled water, ion-exchanged water, or other various purified water. The amount of water used is sufficient to make the whole oil-in-water emulsion composition 100%.

< preparation method of oil-in-water emulsion composition >

The oil-in-water emulsion composition of the present invention can be produced by a method generally used for producing an emulsion. For example, the composition can be produced by preparing an oil phase component and an aqueous phase component separately, mixing the aqueous phase and the oil phase, and emulsifying the mixture with a disperser or homogenizer.

The method for forming the oil-in-water emulsion system of the present invention is not particularly limited, and a stable emulsion can be obtained by mixing the oil phase component and the water phase component by mechanical stirring or ultrasonic treatment, provided that the essential components of the present invention are present.

Similarly, the apparatus for preparing the oil-in-water emulsion composition of the present invention is not particularly limited as long as the above requirements can be satisfied.

The oil-in-water emulsion composition of the present invention may be in the form of an emulsion or a microemulsion, and may be in the form of a transparent, translucent or opaque emulsion.

From the viewpoint of production and use, the oil-in-water emulsion composition obtained by the present invention has a viscosity of 1500-. If the viscosity is too low, the effect of the product in use may be impaired, while if the viscosity is too high, the production may be impaired.

< other additives >

As an optional ingredient of the oil-in-water emulsion composition of the present invention, various other components or functional ingredients which are conventional in the art may be added without any limitation as long as the above-mentioned effects of the present invention are not impaired.

The oil phase used in the oil-in-water emulsion composition of the present invention may contain other types of oil components in addition to the volatile silicone oil (a) as the essential component, without affecting the technical effects of the present invention.

The oil component can be selected from those used in usual cosmetics within a range that does not impair stability. Preferred oil components include: hydrocarbon oil, liquid oil and fat, ester oil, and silicone oil other than the volatile silicone oil (a) of the present invention.

As the hydrocarbon oil, liquid paraffin, squalane, squalene, paraffin, isoparaffin, ceresin, vaseline, hydrogenated polydecene, and the like can be used.

Examples of the silicone oil other than the volatile silicone oil (a) of the present invention include: chain silicones such as methylphenyl polysiloxane and methylhydrogenpolysiloxane; silicone resin, silicone rubber, or the like, which is formed with a three-dimensional network structure.

As the liquid grease, there may be included: palm oil, palm kernel oil, linseed oil, camellia oil, macadamia nut oil, corn oil, mink oil, olive oil, avocado oil, camellia oil, castor oil, safflower oil, jojoba oil, sunflower oil, almond oil, rapeseed oil, sesame oil, soybean oil, peanut oil, diglycerol, tricaprylin, triglycerol, and the like.

As the ester oil, there may be included: cetyl octanoate, hexyl laurate, isopropyl myristate, octyl palmitate, isocetyl stearate, isopropyl isostearate, octyl isopalmitate, isodecyl oleate, cetyl ethylhexanoate, glyceryl tri-2-ethylhexanoate, pentaerythritol tetra-2-ethylhexanoate, 2-ethylhexyl succinate, diethyl sebacate, and the like.

It goes without saying that the amount of these other oils is not limited to the upper limit of the amount which does not affect the technical effects of the present invention.

The oil-in-water emulsion composition of the present invention may further contain other water-soluble thickening components, and examples of the water-soluble thickening agent include: plant polymers such as gum arabic, tragacanth gum, galactan, guar gum, carrageenan, pectin, quince seed (marmelo) extract, and brown algae powder, microorganism polymers such as xanthan gum, dextran, pullulan, and succinoglycan, and animal polymers such as collagen, casein, albumin, and gelatin; starches such as carboxymethyl starch and methyl hydroxy starch, celluloses such as methyl cellulose, nitrocellulose, ethyl cellulose, methyl hydroxypropyl cellulose, hydroxyethyl cellulose, cellulose sulfate, hydroxypropyl cellulose, carboxymethyl cellulose, crystalline cellulose and cellulose powder, vinyl polymers such as polyvinyl alcohol, polyvinyl methyl ether, polyvinyl pyrrolidone and carboxyvinyl polymer, acrylic polymers such as polyacrylamide and sodium dimethylacrylamide/acryloyldimethyltaurate) crosslinked polymers, and glycyrrhizic acid, alginic acid and salts thereof.

In addition, various components generally blended in the fields of cosmetics and quasi drugs may be appropriately blended as necessary, for example: other volatile components, powder component, humectant, metal ion chelating agent, pigment, pH regulator, skin nutritional agent, vitamins, antiseptic, antioxidant auxiliary agent, perfume, etc.

Various additives, which may also be enumerated: whitening additives, anti-aging additives, acne-removing additives, ultraviolet-proof additives, and applicable plant essences or plant extracts.

Further, inorganic functional additives such as silica, mica and the like may be added according to the need of cosmetic products, and the amount of the inorganic component is preferably 1% or less, more preferably 0.7% or less, based on the total mass of the oil-in-water emulsion composition of the present invention.

< cosmetics >

In particular, the present invention also provides a cosmetic composition comprising the oil-in-water emulsion composition. The type of cosmetic used in the present invention is not particularly limited, and skin-care cosmetics, hair-care cosmetics, and the like are mainly used. The product can be emulsion, essence, floral water, etc., or similar products thereof.

Examples

The invention will be further described in the following with specific preferred embodiments. In particular, the embodiments of the present invention are not limited thereto, and the following specific examples do not limit the technical aspects of the present invention.

Examples 1 to 4

An oil-in-water emulsion composition formed according to the following formulation, giving examples 1 to 3, the specific formulations being listed in tables [1] to [3], and example 4 being listed in table [6 ]:

TABLE [1]

TABLE [2]

Table [3]

Example 4

The emulsion composition of example 4 was obtained by mixing the components in the proportions shown in Table [6 ].

Note: in 4 examples:

the volatile silicone oil is polydimethylsiloxane, and the structural formula of the volatile silicone oil is as follows:

experimental example 1

An emulsion composition was obtained in the same manner as in example 4 except that the amount of polydimethylsiloxane in example 4 was adjusted to 15% by weight (while the amount of water was adjusted only adaptively).

< evaluation results >

Somatosensory evaluation

Experience of lubricity of the coated skin

The test specimen was applied to the back of the hand of 21 female panelists by hand, and the lubricating sensation after application was investigated by questionnaire and evaluated according to the following criteria.

◎ the answer is very lubricated.

○ the answer is comparative lubrication.

△ the answer is that the sensation of lubrication is not noticeable.

X: the answer was no feeling of lubrication.

Experience of a refreshing feel of the coated skin

The test sample was applied to the back of the hand of 21 female panelists by hand, and the refreshing feeling of the skin after application was investigated and evaluated according to the following criteria.

◎ the response is very fresh.

○ the answer is more refreshing.

△ the answer is a refreshing feel.

X: the response was no fresh feel.

TABLE [4] evaluation results of example 4

Numbering	Sense of lubricity	Refreshing feeling
			1	○	○
2	◎	◎
			3	○	◎
4	◎	◎
			5	◎	◎
6	◎	○
			7	◎	○
8	◎	○
			9	◎	△
10	○	○
			11	◎	◎
12	△	◎
			13	○	○
14	◎	○
			15	○	◎
16	◎	◎
			17	◎	◎
18	◎	◎
			19	○	◎
20	◎	○
			21	◎	○

TABLE [5] evaluation results of Experimental example 1

Numbering	Sense of lubricity	Refreshing feeling
			1	◎	◎
2	○	○
			3	◎	○
4	○	○
			5	○	○
6	○	△
			7	○	◎
8	○	◎
			9	○	△
10	◎	◎
			11	○	○
12	△	○
			13	◎	◎
14	○	◎
			15	◎	○
16	○	○
			17	○	○
18	○	○
			19	◎	○
20	○	◎
			21	○	◎

As can be seen from the human sensory comparative tests in tables [4] and [5] above, when the amount of volatile silicone oil, i.e., polydimethylsiloxane, is less than the amount defined in the present invention, the lubricity to the human body and the refreshing feeling are reduced.

Examples 4 and examples 4 based experimental examples 1 to 12, which were obtained by univariate variation of the different components, are shown and compared below, and based on this the effect of the type of components (a) to (C) and the content of each component in the present invention on the emulsion composition will be discussed. Wherein:

experimental examples 1 to 5 were obtained by adjusting the content of volatile silicone oil based on example 4;

experimental examples 6 to 9 were obtained by using the surfactants having different HLB values instead of example 4, wherein,

the HLB value of "PEG-20 hydrogenated castor oil" was 10.5,

"behenyl polyether-10" has an HLB value of 10,

the HLB value of "PEG-5 glyceryl stearate" was 9,

the HLB value of "PEG-12 dioleate" is 7;

experimental example 10 was obtained by adjusting the content of the surfactant based on example 4;

examples 11 to 12 were obtained by adjusting the content of the polymer compound having an emulsifying ability in addition to example 4.

Further, the indexes of example 4 and experimental examples 1 to 12 were tested, as shown in Table 6 below.

Conditions of rolling experiment: the emulsion was placed in a glass bottle, which was placed horizontally at 45 rpm and rolled for 4 hours.

Where "○" indicates that the appearance passed or the rolling test passed, and "x" indicates that the appearance was delaminated or that the system was unstable in the rolling test.

Watch [6]

According to the test results, the following results are obtained:

influence of (A) content of volatile Silicone oil

The content of the component a in experimental example 1 was 15% which is less than 20% defined in the present invention, and although the viscosity and stability of the resulting emulsion were in an acceptable state, the lubricity and refreshing feeling of the human body were lowered and the effect was not satisfactory when used by the human body as described above, and thus it was within the range excluded by the present invention.

When the content of the A component is 35% or more (Experimental examples 3-5), the oil-in-water system may be unstable due to the increase of the oil phase content, that is, there may be a delamination phenomenon which is noticeable from the appearance. However, it should be noted that, since the stability of the system is also related to the contents of the components (B) and (C), and various other components may be contained in the oil-in-water emulsion composition of the present invention, although the instability of the system occurs when the content of the component (a) is 35% or more in the above experimental examples 3 to 5, this does not mean that the case where the content of the component (a) is 35% or more in the present invention is not at all practicable, but only the embodiment where the content of the component (a) is 35% or more is not preferable in the present invention in order to ensure that an absolutely good effect is obtained.

< influence of nonionic surfactants having different HLB values >

In examples 6 to 9, the surfactant in example 4 was replaced with a surfactant having an HLB value of less than 11, and it can be seen that each of the examples after replacement failed to obtain satisfactory system stability.

< influence of amount of nonionic surfactant >

In experimental example 10, the amount of the nonionic surfactant of the present invention was adjusted to 0.2%, and in this case, the composition obtained was also able to obtain satisfactory stability and system viscosity, and therefore, although the present invention is not limited in principle to the lower limit of the (C) component (i.e., as long as it is present as an essential component), it is preferable to limit the amount of the (C) component to 0.2% or more.

Influence of the amount of Polymer Compound having emulsification ability >

The content of the (B) component was defined as 0.04% and 0.35% in experimental example 11 and experimental example 12, respectively.

From the data of experimental example 12, when the content of the (B) component is 0.35%, the system viscosity reaches 29400 mPas, and therefore, it is inferred that when the amount of the (B) component is further increased, the system viscosity will also increase, whereas if the system viscosity is too large (e.g., more than 30000 mPas in some cases), it is generally considered to be disadvantageous for industrial production.

From experimental example 11, when the amount of the (B) component is 0.04%, unfavorable conditions may occur in the rolling test. Of course, such experimental example 11 was obtained only in the case of the specific amounts of (A) and (C), and therefore, it is understood that such a result is not to say that the present invention cannot be carried out at all when the amount of (B) component is 0.04% or less, but that the amount of (B) component is limited to more than 0.04% as a preferable range of the present invention in consideration of various extreme possibilities.

Industrial applicability

The oil-in-water emulsion composition of the present invention can be produced in industrial production, and can also be used for the production of cosmetic products.

Claims

1. An oil-in-water emulsion composition comprising the following essential components:

(C) a nonionic surfactant having an HLB value of 11 or more,

the content of the component (A) is 20 mass% or more and less than 35 mass%, the content of the component (B) is 0.35 mass% or less and more than 0.04 mass%, the content of the component (C) is 2 mass% or less and 0.2 mass% or more,

the component (B) is a high molecular compound with emulsifying capacity, and is selected from one or a mixture of more than two of (methyl) acrylic acid, C10-C30 alkyl ester polymers of (methyl) acrylic acid or copolymers thereof.

2. The composition as claimed in claim 1, wherein the high molecular compound having emulsifying ability of component (B) is a copolymer of a (meth) acrylic monomer and a C10-C30 alkyl (meth) acrylate monomer.

3. The composition according to claim 1 or 2, wherein the component (C), the nonionic surfactant, has an HLB value of 13 to 15.

4. Composition according to claim 1 or 2, characterized in that the volatile silicone oil of component (a) comprises a linear polydimethylsiloxane.

5. The composition according to claim 1 or 2, wherein the (a) component is used in an amount of 20 to 30% by mass, the (B) component is used in an amount of 0.05 to 0.2% by mass, and the (C) component is used in an amount of 0.2 to 1.5% by mass.

6. A process for the preparation of a composition according to any one of claims 1 to 5, characterized in that it comprises a step of mixing the components (A) to (C) with an aqueous phase and a step of subjecting the mixture obtained to a stabilization treatment so as to obtain a stable emulsion system.

7. A cosmetic characterized in that it comprises a composition according to any one of claims 1 to 5.

8. The cosmetic according to claim 7, wherein the cosmetic is a skin-care cosmetic or a hair-care cosmetic.