WO2018059998A1

WO2018059998A1 - Emulsion composition for hair cosmetics

Info

Publication number: WO2018059998A1
Application number: PCT/EP2017/073564
Authority: WO
Inventors: Airi SENGOKU; Kenji Igarashi
Original assignee: Wacker Chemie Ag
Priority date: 2016-09-30
Filing date: 2017-09-19
Publication date: 2018-04-05
Also published as: JP2018052900A; JP6765922B2

Abstract

An emulsion composition for hair cosmetics, which enables efficient treatment to hair, adds body and a smooth touch to hair, and can be stably used is provided. The emulsion composition comprises (A) 20 to 80 parts by mass of organopolysiloxane having an average composition represented by the general formula (1) : R¹ _aSiO_(4-a)/2 (1) [wherein R¹s may be the same as or different from each other in a molecule, and are each a group selected from the group consisting of a saturated or unsaturated monovalent hydrocarbon group of 1 to 25 carbon atoms optionally having a substituent, an aromatic group of 6 to 30 carbon atoms optionally having a substituent, a hydroxy1 group, an alkoxy group of 1 to 6 carbon atoms, and a hydrogen atom, and a is 1.5 to 2.5], (B) 0.3 to 10 parts by mass of silica particles each having on its surface a hydrophobized portion and a silanol group, and (C) water. In this composition, the silica particles of the component (B) is disposed at the interface between an oil phase of an oil droplet of the organopolysiloxane of the component (A) and an aqueous phase of the water of the component (C).

Description

DESCRIPTION

EMULSION COMPOSITION FOR HAIR COSMETICS TECHNICAL FIELD

[0001]

The present invention relates to an emulsion composition for hair cosmetics which adds body to hair and has the

excellent properties of providing a smooth touch.

BACKGROUND ART

[0002]

Inorganic particles such as silica particles are recently used as a material for providing proper elasticity to hair and adding body to hair in applications for hair cosmetics, particularly in fields of conditioners and styling.

[0003]

The technology for providing body to hair by the cohesion of inorganic particles has been known as disclosed in Patent Literature 1. However, in this case, the inorganic particles such as silica exist in lumps on hair fiber. Accordingly, the excessively strong adhesion of particles causes the degree of adhesion among hairs to exceed a desired degree. Thus, there has been a problem in which the touch of the treated hair becomes in an unfavorable state in which added body to hair becomes too much, thereby causing dryness and brittleness which leads to the sense of extreme hardness. There has been another problem in which the friction of hair is significantly- increased, promoting the damage of hair.

[0004]

For solving the above-described problem, there has been developed a method of mixing an oil and inorganic particles to be used in a composition for hair cosmetics as disclosed in Patent Literatures 2 and 3. However, the mixing of an oil phase and inorganic particles causes the inorganic particles to remain in the oil phase or to be coated with an oil

component. Accordingly, the cohesion among the particles markedly decreases. Thus, the effect of adding body to hair decreases. For compensating for the decrease of the effect of adding body to hair, it was required to separately add a clay mineral or the like which gives high thixotropy to the

composition. In this case, there was a problem in which only a touch different from the originally desired touch of added body to hair is obtained.

[0005]

For solving this problem, Patent Literature 4 proposes, as a composition for hair cosmetics, a composition which is one composition while separately including an oil phase and inorganic particles. However, in this method, inorganic particles are added afterward into an oil-in-water emulsion which has been separately prepared with an organic surfactant. Therefore, the inorganic particles are dispersed by the free surfactant in the oil-in-water emulsion. Accordingly, the cohesion among the particles is weak in the composition for hair cosmetics and even after the use thereof. As a result, there has been a problem in which the effect of providing the touch of added body to hair is low.

[0006]

Moreover, examples of a known organic surfactant include alkyl polyether having an alkyl group of 12 to 15 carbon atoms, and polyoxyethylene alkyl sulfates. According to PRTR

(Pollutant Release and Transfer Register) , these surfactants are designated as chemicals which could adversely affect the environment, and the emissions and the like thereof are

regulated. Thus, there has also been a problem that the

selection thereof is becoming limited.

[0007]

Also, Patent Literature 5 discloses a method of

emulsifying a silicone component with silica particles instead of a known surfactant thereby to obtain silicone particles.

However, specific requirements and processes required for applying the emulsion to hair cosmetics have not been

disclosed.

CITATION LIST PATENT LITERATURE

[0008] i

Patent Literature 1: WO0130310 (Al)

Patent Literature 2: WO2005070374 (Al)

Patent Literature 3: O2006018065 (Al)

Patent Literature 4: O2006081910 (Al)

Patent Literature 5: O2007113095 (Al)

SUMMARY OF INVENTION TECHNICAL PROBLEM

[0009]

Therefore, any of the known technologies has not

disclosed a specific method for providing a smooth touch while adding body to hair in uses for hair cosmetics.

[0010]

In view of the above-described circumstances, the present invention provides an emulsion composition for hair cosmetics, which enables efficient treatment to hair, that is, uniform treatment to hair even with a small amount, adds body to hair while providing a smooth touch, and can be stably used.

SOLUTION TO PROBLEM

[0011]

The present inventors have intensively conducted studies, and found that a polyorganosiloxane emulsion in which the surfaces of emulsion particles are coated with silica

particles has excellent characteristics in the development of uses, thereby eliminating limitations to its uses.

Also, the present inventors have found the condition for adding body to hair while providing a favorable touch due to organopolysiloxane in uses for hair cosmetics, based on the shape and property characteristics of the polyorganosiloxane emulsio .

[0012]

The present invention has been achieved on the basis of the above-described knowledge.

That is, the emulsion composition for hair cosmetics according to the present invention comprises:

(A) 20 to 80 parts by mass of organopolysiloxane having an average composition represented by the general formula (1) :

wherein I^s may be the same as or different from each other in a molecule, and are each a group selected from the group consisting of a saturated or unsaturated monovalent hydrocarbon group of 1 to 25 carbon atoms optionally having a substituent, an aromatic group of 6 to 30 carbon atoms

optionally having a substituent, a hydroxyl group, an alkoxy group of 1 to 6 carbon atoms, and a hydrogen atom, and a is 1,5 to 2,5;

(B) 0.3 to 10 parts by mass of silica particles each having on a surface thereof a hydrophobized portion and a silanol group and

(C) water.

In the composition, the silica particles of the component (B) is disposed at an interface between an oil phase of an oil droplet of the organopolysiloxane of the component (A) and an aqueous phase of the water of the component (C) .

[0013]

The organopolysiloxane of the component (A) may

preferably contain dimethylpolysiloxane having a viscosity at

25°C of 10, 000 mPa-s or more.

[0014]

The organopolysiloxane of the component (A) may

preferably contain amino-modified dimethylpolysiloxane in some cases .

ADVANTAGEOUS EFFECTS OF INVENTION

[0015]

The emulsion composition for hair cosmetics according to the present invention is an emulsion composition which

comprises organopolysiloxane as a base component. In the emulsion composition for hair cosmetics, the silica particles are disposed at the interface between an oil phase as the organopolysiloxane and an aqueous phase, without recourse to generally used nonionic, anionic, cationic, or amphoteric, organic surfactants .

The silica particles of the component (B) have

appropriate compatibility with both an oil phase and an aqueous phase. Therefore, the silica particles can be disposed at an oil phase/aqueous phase interface and provide an oil-in- water emulsion with an aqueous phase as a continuous phase. Differently from emulsions obtained with generally used organic surfactants, the particle size of the obtained emulsion is unlikely to be affected by the polarity of an oil phase to be dispersed. Thus, the particle size can be stably controlled in a wide range of oily components, thereby

reducing the variations of the particle size.

This enables the emulsion to be stably used in a series of processes, such as preparation and preservation of the emulsion, preparation and preservation of cosmetics containing the emulsion, and treatment of hair.

[0016]

Since the emulsion composition for hair cosmetics according to the present invention becomes in such a favorable state when used for the uses of hair cosmetics, an appropriate amount of the emulsion particles can be uniformly attached on hair, compared to a case in which only inorganic particles are used, a case in which inorganic particles are dispersed in water and oil, or a case in which the used emulsion is in an unfavorable state.

Furthermore, the surface of the particles is not coated with an excessive oil content. This causes the cohesion among the particles to increase. As a result, there is added appropriate elasticity, that is, body, to the whole hair. At the same time, since hair can be effectively coated with a silicone component, a smooth touch can be provided.

[0017]

Also, since an oil phase is not significantly thickened compared to a case in which silica particles are thoroughly mixed with an oil phase, there can also be used an oil phase component with high viscosity, which is preferred in uses for hair cosmetics.

DESCRIPTION OF EMBODIMENTS

[0018]

Hereinafter, the emulsion composition for hair cosmetics according to the present invention will be described in detail.

[0019]

(Component (A) )

Component (A) is organopolysiloxane having an average composition represented by the general formula (1) :

R^SiO^ -a) ^ ⁽D

[in the formula (1) , R^-s may be the same as or different from each other in a molecule, and are each a group selected from the group consisting of a saturated or unsaturated

monovalent hydrocarbon group of 1 to 25 carbon atoms

optionally having a substituent, an aromatic group of 6 to 30 carbon atoms optionally having a substituent, a hydroxy1 group, an alkoxy group of 1 to 6 carbon atoms, and a hydrogen atom, and a is 1.5 to 2.5]. ¹ bound to a silicon atom in the component (A) is

preferably a monovalent hydrocarbon group of 1 to 13 carbon atoms optionally having a substituent.

[0020]

Example of the above -described organic group may

specifically include: an alkyl group, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, a pentyl group, a neopentyl group, a hexyl group, a 2-ethylhexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and a dodecyl group; a cycloalkyl group, such as a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group; an aryl group, such as a phenyl group, a tolyl group, a xylyl group, a

biphenyl group, and a naphthyl group; an aralkyl group, such as a benzyl group, a phenylethyl group, a phenylpropyl group, and a methylbenzyl group; a nitrogen-containing hydrocarbon group represented by -CH₂-CH₂-CH₂-NH₂ , -CH₂-CH₂-CH₂-NH (CH₃) , - CH₂-CH₂-CH₂-N(CH₃) ₂, -CH₂-CH₂-NH-CH₂-CH₂-NH₂, -CH₂-CH₂-CH₂-NH (CH₃) , -CH₂-CH₂-CH₂-NH-CH₂-CH₂ -NH₂ , -CH₂-CH₂-CH₂-NH-CH₂-CH₂-N ( CH₃ ) ₂ , -CH₂- CH₂-CH₂-NH-CH₂-CH₂-NH (CH₂CH₃) , -CH₂-CH₂-CH₂-NH-CH₂-CH₂-N (CH₂CH₃) ₂ , and -CH₂-CH₂-CH₂-NH-CH₂-CH₂-NH (cyclo-CgHn) ; and a substituted hydrocarbon group in which a portion or an entirety of

hydrogen atoms in a hydrocarbon group is substituted with a halogen atom, a cyano group, and the like, such as a

chloromethyl group, a 2-bromoethyl group, a 3,3,3- trifluoropropyl group, a 3 -chloropropyl group, a chlorophenyl group, a dibromophenyl group, a tetrachlorophenyl group, a difluorophenyl group, a β-cyanoethyl group, a γ-cyanopropyl group, and a β-cyanopropyl group. Particularly preferable organic groups are a methyl group, a -CH₂-CH₂-CH₂-NH-CH₂-CH₂-NH₂ group , and a phenyl grou .

[0021]

The component (A) may be linear or branched. The viscosity at 25°C of the component (A) is preferably 5 to 2,000,000 mPa-s, more preferably 50 to 100,000 mPa^s, and particularly preferably 100 to 50,000 mPa-s . When the

viscosity is less than 5 mPa^s, and when it is more than

2,000,000 mPa-s, emulsification is difficult, thereby

inhibiting a stable aqueous dispersion liquid from being obtained. Furthermore, the content of the component (A) is preferably 19.95 to 79.95 parts by mass. When the content is less than 19.95 parts by mass, sufficient emulsification accuracy is not obtained, and the yield decreases. When the content is more than 79.95 parts by mass, the viscosity of the aqueous emulsion increases, thereby causing handling

properties to be reduced. The content of the component (A) is more preferably 30 to 70 parts by mass.

[0022]

The organopolysiloxane of the component (A) is not particularly limited, as long as the above-described conditions are satisfied. The chemical structure, molecular weight, and characteristics thereof are not limited. Also, the organopolysiloxane of the component (A) may be a mixture of two or more polymers .

However, the component (A) preferably contains

dimethylpolysiloxane having a viscosity at 25°C of 10,000 mPa-s or more. This is because the absence of such

dimethylpolysiloxane causes deterioration of the adherence when rinsing hair in hair-care uses. In addition, even when not rinsing hair, a touch or the like is unlikely to be maintained. This is particularly significant when a component that promotes adsorption of the whole component (A) to hair, such as modified polysiloxane , is not contained, and only the dimethylpolysiloxane is contained. When the

dimethylpolysiloxane having a viscosity at 25°C of 10,000 mPa-s or more is contained, the viscosity of the whole component (A) needs to fall within the above-described range.

[0023]

Also, it is sometimes preferable that the

organopolysiloxane of the component (A) contain amino-modified dimethylpolysiloxane. Since amino-modified

dimethylpolysiloxane has good adherence to hair, it can be used for the purpose of improving adherence when the use thereof is acceptable. The use of the amino-modified

dimethylpolysiloxane is particularly effective when the viscosity of the whole component (A) is low. This is because an amino group is cationized by protonation, and adheres to hair .

[0024]

The chemical structure, molecular weight, and physical properties of such amino-modified organopolysiloxane are not particularly limited, as long as the average structure as a whole of the component (A) satisfies the above-described general formula (1) , and the physical properties such as the viscosity thereof also satisfy the above-described conditions. Also, the molecular structure of the amino-modified

organopolysiloxane may be not only linear but also branched. However, a branched structure is preferable.

An example of R¹ in the general formula (1) includes a hydrocarbon group having two or more amino groups, which is represented by the following general formula (2) :

-R²- [ (NR³) -R⁴] _tNR⁵R⁵ (2)

wherein, R² and R⁴ represent a divalent hydrocarbon residue of 1 to 18 carbon atoms, R³ , R⁵, and R^s represent a hydrogen atom or an alkyl group of 1 to 10 carbon atoms, and t represents 0 or a positive number of 6 or less. Such a hydrocarbon group is contained as part of all R¹s .

[0025]

Examples of the divalent hydrocarbon residue of 1 to 18 carbon atoms as R² and R⁴ include a methylene group, an ethylene group, an n-propylene group, an iso-propylene group, an n-butylene group, an iso-butylene group, a t-butylene group, an n-pentylene group, an iso-pentylene group, a hexylene group such as an n-hexylene group, a heptylene group such as an n- heptylene group, an octylene group such as an n-octylene group and an iso-octylene group such as a 2,2,4 - trimethylpentylene group, a nonylene group such as an n-nonylene group, a

decylene group, a dodecylene group such as an n-dodecylene group, and an octadecylene group. An example of the alkyl group as R³ , R⁵ , and R^e includes an alkyl group of 10 or less carbon atoms .

[0026]

Examples of preferable R¹ in the amino-modified

organopolysiloxane may include - CH₂ - CH2 - CH₂ -NH₂ , - CH₂ - CH₂ - CH₂ - NH(CH₃), -CH₂-CH₂-CH₂-N(CH₃) ₂ , -CH₂-CH₂-NH-CH₂-CH₂-NH₂ , -CH₂-CH₂- CH₂-NH(CH₃) , -CH₂-CH₂-CH₂-NH-CH₂-CH₂-N(CH₃) ₂, -CH₂-CH₂-CH₂-NH-CH₂- CH₂-NH(CH₂CH₃) , -CH₂-CH₂-CH₂-NH-CH₂-CH₂-N(CH₂CH₃) ₂, and -CH₂-CH₂- CH₂-NH-CH₂-CH₂-NH (cyclo-C₆Hn) . R¹ which is suitable for

cosmetics is preferably - CH₂ - CH₂ - CH2 - H2 and CH₂-CH₂-CH₂-NH-CH₂- CH₂-NH₂, and particularly preferably CH₂-CH₂-CH₂-NH-CH₂-CH₂-NH₂.

[0027]

The ratio between the average number of ^^'s with an amino group and the average number of R^xs without an amino group is 15 to 600. This serves as a rough standard for the ratio between a siloxane unit with an amino group and a siloxane unit without an amino group. As an indication of the total amount of amino groups in the amino-modified

organopolysiloxane, there is also used an amine number

represented by the volume (mL) of 1 N hydrochloric acid required for neutralizing 1 g of the amino-modified

organopolysiloxane. This amine number varies depending on the number and the molecular weight of the amino groups in one molecule of the amino-modified polyorganosiloxane . The amine number of the amino-modified organopolysiloxane in the present invention needs to be 0.1 to 3.0, and preferably 0.15 to 2.0. When the amine number is 0.1 or less, the ability to adsorb to the surface of hair decreases . When the amine number is 3.0 or more, the number of amino groups as a hydrophilic group excessively increases, thereby inhibiting adsorption to hair.

[0028]

The viscosity at 25°C of such amino-modified

organopolysiloxane is 100 to 10,000 mPa-s, and preferably 200 to 2,000 mPa-s. When the viscosity is less than 100 mPa-s, the effect of conditioning hair cannot be sufficiently obtained. When it is more than 10,000 mPa^s, smoothness and manageability cannot be added to hair up to the tips thereof. It is noted that when the amino-modified organopolysiloxane is also contained as the component (A) , the viscosity of the amino- modified organopolysiloxane needs to be selected such that the viscosity range of the whole component (A) follows the condition ,

[0029]

Such amino-modified organopolysiloxane is commonly known as an amino-modified silicone oil, and can be manufactured by a method known to those skilled in the art. A representative method for synthesizing the amino-modified silicone oil is as follow .

That is, introduction of an amino alkyl group to a

silicon atom is usually performed in the stage of silane. Thus, amino alkyl silane is firstly produced. The amino alkyl silane is hydrolyzed into an amino grou -containing siloxane oligomer or an amino group-containing disiloxane. Furthermore, a re- equilibration reaction of an Si-0 bond is performed with a linear oligomer or a cyclic oligomer of dimethyl siloxane in the presence of an alkali catalyst, thereby to obtain an

amino-modified silicone oil. When hexamethyl disiloxane is used in the re-equilibration reaction, there can be obtained an amino-modified silicone oil having trimethylsilyl at

terminals. Adjusting the ratios of oligomers or disiloxane used in the manufacture can provide an amino-modified silicone oil having a specific kinematic viscosity and a specific amine number. One amino-modified silicone oil can be used alone, or two or more amino-modified silicone oils can be used as a mixture, as long as the kinematic viscosity and the amine number fall within the respective ranges of the present invention .

[0030]

(Component (B) )

The silica particles of the component (B) according to the present invention have on its surface a hydrophobized portion and a silanol group, and can be disposed at the interface between an oil phase of an oil droplet of the organopolysiloxane of the component (A) and an aqueous phase in the aqueous phase of an emulsion. On the surface of such silica particles, there exist a silanol group as a hydrophilic group and a hydrophobized silanol group at a predetermined ratio. Accordingly, the balance between hydrophilicity and hydrophobicity of the particles is controlled. Thus, the particles are disposed at the interface between the oil phase constituted by the organopolysiloxane of the component (A) and the aqueous phase, and exert an emulsification effect like those possessed by known organic surfactants.

[0031]

The silica particles of the component (B) are particles of silicon dioxide manufactured by a synthesis method, and do not include mineral -based silica particles such as

diatomaceous earth and crystal quartz. Examples of the silicon dioxide manufactured by a synthesis method may include fine particles obtained by a dry process, such as fumed silica, pyrogenic silica, and fused silica, and precipitated silica or colloidal silica obtained by a wet process. These are well known to those skilled in the art. Among these, pyrogenic silica, precipitated silica or colloidal silica is preferably used. The silica particles of the component (B) according to the present invention may be hydrophilic silica on which a silanol group remains, or hydrophobic silica obtained by silylating a silanol group on the surface. Hydrophobic silica can be manufactured by a known method in which hydrophilic silica is treated with halogenated organic silicon such as methyltrichlorosilane , alkoxysilanes such as

dimethyldialkoxysilane , silazane, and low-molecular weight methylpolysiloxane .

[0032]

When silica having on its surface a hydrophobized portion and a silanol group is used as the silica particles of the component (B) , the surface tension of the silica particles is set within the range which allows for surface activity.

Accordingly, the silica particles can be stably disposed at the interface between the oil phase of an oil droplet and the aqueous phase even in the absence of generally used

surfactants .

The ratio of silanol remained after silylation relative to a silanol group before the silylation is preferably 50 to 95%. When the ratio of the remained silanol is less than 50% or more than 95%, the effect which the surfactants have at the interface between an oil phase and an aqueous phase cannot be exerted. The ratio of silylation or remained silanol can be determined by measuring a carbon content by elemental analysis or the amount of a remained reactive silanol group on the surface of silica. The silica particles used for preparation may contain particles of which the entire surface is silylated or particles of which the entire surface is not silylated.

However, such silica particles can be used when the silylation ratio as a whole falls within the above-described range, and a necessary emulsification effect can be exerted.

[0033]

The carbon content of the silica particles having a hydrophobized portion and a silanol group, which is suitably used as the component (B) , is not particularly limited, as long as the object of functioning as a surfactant is

accomplished. However, the carbon content is preferably 0.1 to 10%. When the carbon content is less than 0.1% or more than 10%, a stable emulsion cannot be obtained.

[0034]

The content of the component (B) in 100 parts by mass of the emulsion is preferably 0.3 to 10 parts by mass. When the content is less than 0.3 parts by mass, the stability of an aqueous dispersion liquid deteriorates. When it is more than 10 parts by mass, the coat of emulsion particles becomes excessive, thereby causing occurrence of unfavorable phenomena such as coarseness in uses for cosmetics. The content of the component (B) in 100 parts by mass of the emulsion is more preferably 1 to 7 parts by mass.

[0035]

When hair is treated with the emulsion composition for hair cosmetics according to the present invention, which has the above-described configuration, the hair can be efficiently treated, that is, uniformly treated even with a small amount of the composition. At the same time, the increased cohesion among the silica particles causes body to be added to hair.

Also, there is no dryness or the like caused by a hair

treatment agent, and smoothness is provided while the state of having strong bounce to some extent can be maintained.

Furthermore, the emulsion itself stably exists for an extended period. In addition, the stability when formulated in cosmetics and the stability of the state of treated hair are secured.

[0036]

The production method of the emulsion composition for hair cosmetics according to the present invention is not

particularly limited, as long as it does not depart from the scope of the above-described method, and may be a known method. For example, the emulsion composition can be prepared by

mixing and emulsifying the above-described components using a common mixer suitable for the preparation of an emulsion, such as a homogenizer, a colloid mill, a homomixer, and a highspeed stator rotor stirrer. For more advantageously control the shape and properties of the particles in a more industrial and stable manner, there is recommended a method of dispersing 20 to 80 parts by mass of the organopolysiloxane of the component (A) and 0.3 to 10 parts by mass of the silica particles of the component (B) in the water of the component (C) to obtain an oil-in-water type emulsion composition for hair cosmetics .

[0037]

The emulsion composition for hair cosmetics according to the present invention can contain, within the range that does not impair the object of the invention, polyoxyalkylene alkyl ethers such as polyoxyethylene tridecyl ether, polyoxyethylene hexadecyl ether, and polyoxyethylene octadecyl ether, nonionic surfactants such as polyoxyethylene hydrogenated castor oil and polyoxyethylene sorbitan acid ester, ionic surfactants, which are less irritating to the skin, such as sodium lauroyl glutamate and sodium dilauramidoglutamide lysine.

The amount of the surfactant in 100 parts by mass of the emulsion is preferably 0.1 parts by mass or less, and more preferably 0.06 parts by mass or less. When the amount of the surfactant is more than 1 part by mass, the environment is adversely affected. Moreover, the cohesion of the silica particles decreases. Thus, body becomes unlikely to be added to hair thereafter.

[0038]

The emulsion composition for hair cosmetics according to the present invention may preferably, but not particularly limited to, contain ion exchanged water. The pH of the ion exchanged water is preferably pH 2 to 12, and more preferably pH 4 to 10.

[0039]

The emulsion composition for hair cosmetics according to the present invention may contain, within the range that does not impair the object of the present invention, hydrophilic components such as ethanol, 1-propanol, 2-propanol, 1,2- propylene glycol, 1 , 2 -butanediol , 1 , 3 -butanediol , 1,5- pentanediol, 1 , 2 -hexanediol , dipropylene glycol, glycerin, trimethylol propane, and pentaerythritol .

[0040]

The emulsion composition for hair cosmetics according to the present invention may contain, as a preservative,

salicylic acid, sodium benzoate, sodium dehydroacetate ,

potassium sorbate, phenoxy ethanol, methyl parahydroxybenzoate, and butyl parahydroxybenzoate, within the range that does not impair the object of the present invention.

[0041]

The particle size of the organopolysiloxane emulsion composition according to the present invention is, but not particularly limited to, preferably 100 μιτι or less. When the particle size is more than 100 μιη, the particles are

excessively large, thereby inhibiting a uniform touch from being provided to hair.

[Examples]

[0042]

Next, the present invention will be described by way of examples. It is noted that the present invention is not

limited by these examples. The evaluation methods for the oil- in-water type silicone emulsions according to the present invention in examples, and silica/silicone oil compositions in comparative examples, and the evaluation methods for shampoo, conditioner, and treatment compositions in examples and

comparative examples were as described below.

[0043]

Thirty grams of a prepared oil- in-water type silicone emulsion, silica/silicone oil composition, shampoo composition, conditioner composition, or treatment composition was poured into a 50-ml screw vial, and stored at room temperature or 40°C for one month. Thereafter, presence or absence of creaming and sedimentation was observed.

Evaluation criteria:

A: no creaming and no sedimentation observed

B: some degree of creaming and sedimentation observed

C: creaming and sedimentation observed

[0044]

Fifty milliliters of deionized water was poured into a 200-mL polypropylene cup. Then, 5.0 g of each of prepared oil- in-water type silicone emulsions 1 to 4 was further mixed in the cup to obtain a uniform aqueous solution. Thereafter, a hair bundle having a length of 25 cm and a weight of 2.0 g was immersed in the aqueous solution for one minute, subsequently rinsed under running water for 30 seconds, and dried for a day. After that, smoothness and body of touched hair were evaluated by three panelists.

The evaluation was performed by three panelists with a paired comparison method.

Evaluation criteria:

For each sample, one point was given when a touch is excellent, 0 point when poor, and 0.5 points when fair. The evaluation points of three panelists were summed.

[0045]

Evaluation of shampoo and conditioner compositions: A hair bundle having a length of 25 cm and a weight of 2.0 g was rubbed with 1 gram of a prepared composition for one minute, and rinsed under running water at 40°C for one minute. This process was repeated three times. Then, the hair bundle was dried at 25°C for a day. After that, smoothness and body of the hair were evaluated by three panelists.

Evaluation for treatment composition:

One gram of a prepared composition was thoroughly blended into a hair bundle having a length of 25 cm and a weight of 2.0 g for one minute while rubbing the hair bundle from the roots to the tips . The resultant hair bundle was dried for a day. After that, smoothness and body of touched hair were evaluated by three panelists.

The evaluation was performed by three panelists with a paired comparison method. The evaluation for a hair bundle treated with a shampoo composition was performed with a pair of hair bundles having been treated with the shampoo

composition. The evaluation for a hair bundle treated with a conditioner composition or a treatment composition was also performed with a pair of hair bundles having been treated with the conditioner composition or the treatment composition, respectively.

Evaluation criteria:

[0046] <Example 1>

An oil-in-water type silicone emulsion 1 was prepared as described below. As silica particles, there was used dry silica which is an aggregate having a BET surface area of

2,002 m²/g, a carbon content of 10%, and a particle size

distribution of approximately 100 to 1,000 nm. Hereinafter, this is referred to as "silica particles 1." Firstly, 5 parts by mass of the silica particles 1 was stirred at 4,000 rpm and dispersed in 45 parts by mass of water using Ultra-Turrax T50 Basic Shaft Generator G45M manufactured by IKA, thereby to prepare an aqueous dispersion liquid of silica particles. Next, in another container, 25 parts by mass of dimethylpolysiloxane with both terminals blocked by a trimethylsilyl group having a viscosity of 10 mPa^s (25°C) , and 25 parts by mass of

dimethylpolysiloxane having a viscosity of 300,000 mPa^s (25°C) were mixed. Thus, a mixed oil having a viscosity of 20,000 mPa-s (25°C) was prepared. Next, the prepared mixed oil was added to the above-described aqueous dispersion liquid of silica particles while stirring at 4,000 rpm. Thus, an oil-in- water type silicone emulsion 1 was obtained. The formulation is shown in Table 1. The storage stability and the effect of providing a touch to hair with an aqueous solution were

evaluated for the oil-in-water type silicone emulsion 1. The results are shown in Table 2.

Next, according to the formulations in Tables 3 to 5 , basic formulations of a shampoo, a conditioner, and a treatment (out-bath) were prepared. Then, the water- in-oil type silicone emulsion 1 was used to prepare a shampoo

composition, a conditioner composition, and a treatment composition as shown in Table 6. The storage stability and the effect of providing a touch to hair (smoothness and body) were evaluated. The results are shown in Table 7.

[0047]

An oil-in-water type silicone emulsion 2 was obtained by a method similar to that in Example 1, except that 50 parts by mass of dimethylpolysiloxane having a viscosity of 1,000 mPa-s (25°C) was used instead of the mixed oil of 25 parts by mass of dimethylpolysiloxane having a viscosity of 10 mPa-s (25°C) and 25 parts by mass of dimethylpolysiloxane having a viscosity of

300,000 mPa'S (25°C) . The formulation is shown in Table 1.

The storage stability and the effect of providing a touch to hair with an aqueous solution were evaluated for the oil- in-water type silicone emulsion 2. The results are shown in Table 2.

[0048]

An oil-in-water type silicone emulsion 3 was obtained by a method similar to that in Example 1, except that a mixed oil of 25 parts by mass of amino-modified silicone having a viscosity of 1,000 mPa-s (25°C) and 25 parts by mass of

dimethylpolysiloxane having a viscosity of 10 mPa-s (25°C) was used instead of the mixed oil of 25 parts by mass of

dimethylpolysiloxane having a viscosity of 10 mPa^s (25°C) and 25 parts by mass of dimethylpolysiloxane having a viscosity of

300,000 mPa'S (25°C) . The formulation is indicated in Table 1.

The storage stability and the effect of providing a touch to hair with an aqueous solution were evaluated for the oil- in-water type silicone emulsion 3. The results are shown in Table 2.

[0049]

An oil-in-water type silicone emulsion 4 was prepared as described below. Firstly, 25 parts by mass of

dimethylpolysiloxane with both terminals blocked by a

trimethylsilyl group having a viscosity of 10 mPa^s (25°C) , and 25 parts by mass of dimethylpolysiloxane having a viscosity of 300,000 mPa'S (25°C) were mixed. Thus, a mixed oil having a viscosity of 20,000 mPa-s (25°C) was prepared. Furthermore, the mixed oil was stirred at 4,000 rpm with 3 parts by mass of polyoxyethylene isotridecyl ether (EO 10 mol) and 42 parts by mass of water using Ultra-Turrax T50 Basic Shaft Generator G45M manufactured by IKA for dispersion. Thus an oil-in-water type silicone emulsion was obtained. Furthermore, 5 parts by mass of the silica particles 1 was added while stirring at 4,000 rpm. Thus, an oil-in-water type silicone emulsion 4 was prepared. The formulation is shown in Table 1.

The storage stability and the effect of providing a touch to hair in an aqueous solution were evaluated for the oil-in- water type silicone emulsion 4. The results are shown in Table 2.

Next, according to the formulations in Tables 3 to 5, basic formulations of a shampoo, a conditioner, and a

treatment (out-bath) were prepared. Then, the water-in-oil type silicone emulsion 4 was used to prepare a shampoo

[0050]

A silica/silicone oil composition 1 was prepared as described below. Firstly, 45 parts by mass of

dimethylpolysiloxane with both terminals blocked by a

trimethylsilyl group having a viscosity of 10 mPa^s (25°C) , and 45 parts by mass of dimethylpolysiloxane having a viscosity of 300,000 mPa-s (25°C) were mixed. Thus, a mixed oil having a viscosity of 20,000 mPa-s (25°C) was prepared. Furthermore, 10 parts by mass of the silica particles 1 was added while stirring at 4,000 rpm. Thus, a silica/silicone oil composition 1 was prepared. The formulation is shown in Table 1.

The storage stability was evaluated for the

silica/silicone oil composition 1. A test was disabled in the evaluation of the effect of providing a touch to hair in an aqueous solution. The results are shown in Table 2.

Next, according to the formulations in Tables 3 to 5 , basic formulations of a shampoo, a conditioner, and a

treatment (out-bath) were prepared. The water- in-oil type silica/silicone oil composition 1 was used to prepare a shampoo composition, a conditioner composition, and a

treatment composition as indicated in Table 6. The storage stability and the effect of providing a touch to hair

(smoothness and body) were evaluated. The results are shown in Table 7.

[Table 1]

Formulations of oil-in-water type silicone emulsion composition, and silica/oil mixture

Components

[parts by

massl

[Table 2]

Evaluation results of storage stability and effect of providing touch to hair with Aqueous Solution

[Table 3]

[Table 6]

Formulations of sham oo, conditioner, and treatment com ositions

[Table 7]

Evaluation results of stora e stabilit and touch rovided to hair for sham oo conditioner, and treatment com ositions

[Industrial Applicability]

[0051]

The emulsion composition for hair cosmetics according to the present invention enables efficient treatment to hair,

that is, uniform treatment even with a small amount, and

furthermore, can add body and a smooth touch to hair.

Therefore, the emulsion composition for hair cosmetics

according to the present invention exhibits the possibility of expanding the uses for hair cosmetics which provide beautiful appearances and favorable touches .

Also, the use of organic surfactants can be eliminated o: reduced. Therefore, the emulsion composition for hair

cosmetics according to the present invention can resolve the associated environmental problem, achieve stable manufacture, and exist in the form of a stable emulsion. Therefore, there is a possibility that the emulsion composition for hair cosmetics according to the present invention may be

advantageously used in various industries.

Claims

1. An emulsion composition for hair cosmetics comprising:

(A) 20 to 80 parts by mass of organopolysiloxane having an average composition represented by a general formula (1) :

R¹ _aSiO₍₄__a)/2 (1)

wherein R¹s may be the same as or different from each other in a molecule, and are each a group selected from the group consisting of a saturated or unsaturated monovalent hydrocarbon group of 1 to 25 carbon atoms optionally having a substituent, an aromatic group of 6 to 30 carbon atoms optionally having a substituent, a hydroxy1 group, an alkoxy group of 1 to 6 carbon atoms, and a hydrogen atom, and a is 1.5 to 2.5;

(B) 0.3 to 10 parts by mass of silica particles each having on a surface thereof a hydrophobized portion and a silanol group; and

(C) water, wherein

the silica particles of the component (B) is disposed at an interface between an oil phase of an oil droplet of the organopolysiloxane of the component (A) and an aqueous phase of the water of the component (C) .

2. The emulsion composition for hair cosmetics according to claim 1, wherein the organopolysiloxane of the component (A) contains dimethylpolysiloxane having a viscosity at 25°C of 10,000 mPa-s or more.

3. The emulsion composition for hair cosmetics according to claim 1, wherein the organopolysiloxane of the component (A) contains amino-modified dimethylpolysiloxane.

4. A shampoo composition comprising the emulsion composition for hair cosmetics according to any one of claims 1 to 3.

5. A conditioner composition comprising the emulsion composition for hair cosmetics according to any one of claims 1 to 3.

6. A treatment composition comprising the emulsion

composition for hair cosmetics according to any one of claims 1 to 3.