JP7697595B2 - Pigment composition and method for producing the same - Google Patents

Description

The present invention relates to a pigment composition suitable for use in cosmetics, and a method for producing the same.

Pigments are blended for the purpose of coloring in makeup cosmetics such as mascara, eyeliner, eyeshadow, lipstick, etc., and hair cosmetics such as hair dyes, etc. In order to obtain cosmetics with high color development and gloss without color unevenness, it is required that the pigments are uniformly dispersed in the cosmetics.
However, when the affinity between the pigment, which is the coloring component, and other cosmetic components (e.g., solvent components, base components, efficacy/effect components, moisturizing components, etc.) is low, a good dispersion state is not achieved even when shearing (shear force) is applied for a long period of time, and it is difficult to obtain satisfactory color development, gloss, etc. Therefore, there is a problem that surface-treated pigments, in which the pigment surface is coated with a compound, are sometimes used in cosmetics.

JP 2014-101279 A International Publication No. 2007/007521

For example, Patent Document 1 discloses that a surface-treated powder obtained by surface-treating a pigment powder with a cationic organic compound has excellent dispersibility in water, and its use in cosmetics provides excellent feel and adhesion when applied to the skin. An example of the cationic organic compound is vinylpyrrolidone-N,N-dialkylaminoethyl methacrylic acid copolymer dialkyl sulfate.
Furthermore, Patent Document 2 discloses that a surface-treated powder obtained by coating the surface of a powder such as an organic pigment with a water-soluble polyoxyalkylene glycol derivative (hydrophilization treatment agent) has excellent dispersibility and long-term dispersion stability, and is suitable for use in cosmetics.

However, the methods described in the above Patent Documents 1 and 2 still have room for improvement in terms of affinity with aqueous solvents.
An object of the present invention is to provide a pigment composition that has excellent dispersibility (affinity) when mixed with an aqueous solvent and can be used in cosmetics, and a method for producing the same.

As a result of intensive research into solving the above problems, the inventors have discovered that by combining a pigment with a sulfosuccinic acid compound, it is possible to provide a pigment composition that solves the above problems, and a method for producing the same, and have thus completed the present invention, which is described below.

That is, the present invention includes the following aspects.
[1] A pigment composition comprising a pigment (A) and a sulfosuccinic acid compound (B).
[2] The pigment composition according to [1] above, wherein the sulfosuccinic acid compound (B) is a sulfosuccinic acid dialkyl ester represented by the following formula (B-1) or a salt thereof:

（式（Ｂ－１）中、Ｒ^１及びＲ^２は、それぞれ独立に炭素原子数６以上２２以下のアルキル基又はシクロアルキル基を示し、Ｘは無機又は有機の陽イオンを示す。）
[３]前記スルホコハク酸化合物（Ｂ）が、前記顔料（Ａ）の表面の少なくとも一部を被覆してなる、前記[１]又は[２]の顔料組成物。
[４]さらに反応性ゲル化剤を含有する、前記[１]～[３]のいずれかの顔料組成物。
[５]前記[１]～[４]のいずれかの顔料組成物を含有する化粧料。
[６]メークアップ用化粧料、頭髪用化粧料、日焼け・日焼け止め化粧料からなる群から選ばれる化粧料である前記[５]に記載の化粧料。
[７]顔料（Ａ）、スルホコハク酸化合物（Ｂ）及び水系溶媒を混合し、得られた水系混合液を攪拌して分散する工程、及び、攪拌した前記水系混合液を湿式分散機を用いて解砕する工程を有する、顔料組成物の製造方法。

(In formula (B-1), ^R1 and ^R2 each independently represent an alkyl group or a cycloalkyl group having 6 to 22 carbon atoms, and X represents an inorganic or organic cation.)
[3] The pigment composition according to [1] or [2] above, in which the sulfosuccinic acid compound (B) covers at least a part of the surface of the pigment (A).
[4] The pigment composition according to any one of [1] to [3] above, further comprising a reactive gelling agent.
[5] A cosmetic comprising the pigment composition according to any one of [1] to [4] above.
[6] The cosmetic preparation according to [5] above, which is a cosmetic preparation selected from the group consisting of makeup cosmetics, hair cosmetics, and suntan and sunscreen cosmetics.
[7] A method for producing a pigment composition, comprising the steps of mixing a pigment (A), a sulfosuccinic acid compound (B) and an aqueous solvent, stirring the resulting aqueous mixture to disperse the pigment, and disintegrating the stirred aqueous mixture using a wet disperser.

The present invention provides a pigment composition having high affinity for aqueous solvents and excellent dispersibility, and a method for producing a pigment composition that provides a pigment composition having excellent affinity and dispersibility in aqueous solvents.

The present invention will be described in detail below. Note that the explanation of the components described below is merely an example for explaining the present invention, and the present invention is not limited to these contents.

<Pigment Composition>
The pigment composition of the present invention contains a pigment (A) and a sulfosuccinic acid compound (B).
[Pigment (A)]
The pigment (A) (hereinafter, sometimes referred to as "component (A)") is not particularly limited, and for example, organic pigments, inorganic pigments, and dyes used in general inks, paints, recording agents, and the like can be used.

Examples of organic pigments include azo-based, phthalocyanine-based, anthraquinone-based, perylene-based, perinone-based, quinacridone-based, thioindigo-based, dioxazine-based, isoindolinone-based, quinophthalone-based, azomethine azo-based, dicyanopyrrolopyrrole-based, and isoindoline-based pigments.
Examples of inorganic pigments include carbon black, titanium oxide, zinc oxide, tin oxide, iron oxide (yellow ( _FeOOH ), black ( _Fe3O4 ), red _{( Fe2O3} )), zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, red iron oxide, mica, aluminum, bismuth oxychloride, kaolin, talc, manganese, ultramarine, and Prussian blue.
When the pigment composition of the present invention is used for cosmetic applications, it is preferable to use a pigment whose safety when applied to the skin, etc., has been confirmed.

When the pigment composition of the present invention is used for cosmetic applications, it is preferable to use an organic pigment that can be dispersed in a solvent with an average particle size of 50 nm to 500 μm.

[Sulfosuccinic acid compound (B)]
In the present invention, the sulfosuccinic acid compound (B) (hereinafter, sometimes referred to as “component (B)”) refers to a sulfosuccinic acid represented by the following formula (B-0) or a derivative of sulfosuccinic acid represented by the following formula (B-0).
Specific examples of the sulfosuccinic acid derivatives include, in the following formula (B-0), (1) a compound in which one or both H atoms of two hydroxyl groups bonded to a carbon atom are substituted with an organic group or a cation, (2) a compound in which the H atom of a hydroxyl group bonded to a sulfur atom is substituted with an inorganic cation or an organic cation, and (3) a compound having both of the substitutions (1) and (2).

Among these, the sulfosuccinic acid dialkyl ester or its salt represented by the following formula (B-1) is preferred as component (B).

式（Ｂ－１）中、Ｒ^１及びＲ^２は、それぞれ独立に炭素原子数６以上２２以下のアルキル基又はシクロアルキル基である。
Ｒ^１及びＲ^２の炭素原子数６～２２のアルキル基は、直鎖状であっても分岐鎖状であってもよい。
なかでもＲ^１及びＲ^２としては、炭素原子数６～１８のアルキル基又はシクロアルキル基が好ましく、炭素原子数６～１５のアルキル基又はシクロアルキル基がより好ましく、炭素原子数６～１２の直鎖状アルキル基又は分岐鎖状アルキル基がさらに好ましく、炭素原子数６～１０の分岐鎖状アルキル基が特に好ましい。
Ｒ^１、Ｒ^２はそれぞれ同一であっても異なっていてもよいが、同一であることが好ましい。
式（Ｂ－１）中、Ｘは無機の陽イオン又は有機の陽イオンであって、無機陽イオンが好ましい。無機の陽イオンとしては、ナトリウムイオン、カリウムイオン、リチウムイオン等が挙げられ、なかでもナトリウムイオンが好ましい。

In formula (B-1), R ¹ and R ² each independently represent an alkyl group or a cycloalkyl group having 6 to 22 carbon atoms.
The alkyl group having 6 to 22 carbon atoms represented by R ¹ and R ² may be linear or branched.
Among these, ^R1 and ^R2 are preferably an alkyl group or cycloalkyl group having 6 to 18 carbon atoms, more preferably an alkyl group or cycloalkyl group having 6 to 15 carbon atoms, still more preferably a linear alkyl group or branched alkyl group having 6 to 12 carbon atoms, and particularly preferably a branched alkyl group having 6 to 10 carbon atoms.
R ¹ and R ² may be the same or different, but are preferably the same.
In formula (B-1), X is an inorganic cation or an organic cation, preferably an inorganic cation, such as a sodium ion, a potassium ion, or a lithium ion, and more preferably a sodium ion.

By containing the pigment composition of the present invention, the components (A) and (B) come into contact in the composition, and as a result, the surface of the component (A) becomes hydrophilic. From the viewpoint of making the component (A) more hydrophilic, it is preferable that at least a part of the surface of the component (A) is covered with the component (B). In particular, it is preferable that 30% or more (more preferably 50% or more, and even more preferably 80% or more) of the surface area of the component (A) is covered with the component (B). It is also preferable that the surface of the component (A) is entirely covered with the component (B).
As described above, by making the component (A) hydrophilic, the dispersibility and affinity of the pigment composition of the present invention when mixed with an aqueous solvent can be improved, and precipitation and aggregation of the component (A) in the aqueous solvent can be suppressed.

In the pigment composition of the present invention, the content of component (B) is preferably 1 to 100% by mass relative to component (A), more preferably 5 to 50% by mass, and even more preferably 10 to 30% by mass. By making it 10% by mass or more, it is possible to impart sufficient hydrophilicity to component (A), and by making it 30% by mass or less, it is possible to prevent inhibition of coloring or color development by component (A).

In the pigment composition of the present invention, the content of the component (A) in 100% by mass of the pigment composition is preferably 50 to 99% by mass, more preferably 60 to 95% by mass, and even more preferably 70 to 90% by mass.
In the pigment composition of the present invention, the content of the component (B) in 100% by mass of the pigment composition is preferably 1 to 35% by mass, more preferably 3 to 30% by mass, and even more preferably 5 to 25% by mass.

[Other ingredients]
The pigment composition of the present invention may be a composition consisting of only the components (A) and (B), or may be a composition consisting of the components (A) and (B) and trace amounts of other components (solids). In such cases, the pigment composition of the present invention can be a surface-treated pigment in which the component (A) is coated with the component (B) (and trace amounts of other components).
The pigment composition of the present invention may be a liquid composition containing the components (A) and (B) and other solvent components. Preferred solvent components include the aqueous solvents described in the section entitled "Cosmetics" below.

Other components that may be added include a moisturizer (humectant), a preservative, a viscosity adjuster, a pH adjuster, a chelating agent, a plasticizer, an antioxidant, an ultraviolet absorber, and a fragrance. It is also preferable to use a reactive gelling agent that promotes the adhesion of component (B) to component (A).
Examples of moisturizing agents include amino acids such as glutamine, histidine, and arginine; and polyhydric alcohols having two or more hydroxyl groups such as propylene glycol, 1,3-butylene glycol, and glycerin.
Examples of preservatives include alcohols such as 1,2-hexanediol, 1,2-pentanediol, and 1,3-butylene glycol; sodium benzoate; salicylic acid; potassium sorbate; and phenoxyethanol.
The reactive gelling agent is preferably one that reacts with divalent metal ions such as calcium and magnesium in the presence of water to form a gel with a network structure, specifically, carrageenan, pectin, alginic acid or a salt thereof is preferred.Specific examples of alginates include calcium alginate, sodium alginate, potassium alginate, sodium alginate, propylene glycol alginate, siloxanetriol alginate, methylsilanol carboxymethyl theophylline alginate, etc.Of these, calcium alginate and sodium alginate are preferred.
As the metal ion source (ion cross-linking agent) of the divalent metal ion, calcium chloride (CaCl ₂ ), magnesium chloride (MgCl ₂ ), and the like are preferred.
In the pigment composition of the present invention, the content of the reactive gelling agent in 100% by mass of the pigment composition is preferably from 1 to 25% by mass, more preferably from 5 to 20% by mass, and even more preferably from 10 to 15% by mass.

The pigment composition of the present invention can be used in various applications requiring coloration by component (A). The presence of component (B) improves the affinity of component (A) to the aqueous solvent, which prevents precipitation or aggregation of component (A) in the aqueous solvent and allows component (A) to be well dispersed in the aqueous solvent. The "aqueous solvent" intended in the present invention is the same as that described in <Cosmetics> below.
The pigment composition of the present invention can use ingredients that can be used in cosmetics, and is therefore preferably used in cosmetics. As cosmetics, cosmetics using pigments such as makeup cosmetics, hair cosmetics, and suntan/sunscreen cosmetics are preferred. As makeup cosmetics, mascara, eyeliner, eyebrows, eyeshadow, lipstick, nail polish, foundation, cheek color, etc. can be mentioned, and as hair cosmetics, hair color, hair manicure, gray hair dye, hair bleach, shampoo, rinse, conditioner, hair treatment, hair liquid, hair mousse, pomade, hair growth agent, etc. can be mentioned.

<Cosmetics>
The cosmetic of the present invention contains the above-mentioned pigment composition and can be suitably used as a cosmetic. The cosmetic can contain moisturizing components, oily components (emollient components), efficacy/benefit components (whitening components, rough skin improving components, bioactive components, UV protection components, astringent components, stratum corneum/keratin softening components), surfactants (emulsifying components/cleansing components), stabilizing components, preservative/bactericidal components, coloring components other than component (A), solvent components, base components, etc., which are generally used in cosmetics, within the scope that does not impair the effects of the present invention.
Specific examples of compounds that can be incorporated into cosmetics include hydrocarbons, oils and fats such as animal and vegetable oils and mineral oils, waxes, esters, fatty acids, alcohols such as higher alcohols, lower alcohols and polyhydric alcohols, polymeric compounds such as hyaluronic acid, collagen, chitosan, ceramide, cellulose, xanthan gum, polyethylene glycol and various silicone compounds, components derived from animals, plants, algae, microorganisms and the like, amino acids, inorganic minerals, various surfactants, ultraviolet absorbers, skin whitening agents, anti-inflammatory agents, blood circulation promoters, anti-aging agents, moisturizing agents, vitamins, thickeners, gelling agents, antioxidants, preservatives, antibacterial agents, chelating agents, pH adjusters, powders, fragrances, colorants, etc., which can be appropriately combined depending on the desired formulation and function.

As described above, since the pigment composition of the present invention has good dispersibility in aqueous solvents, the cosmetic of the present invention may contain an aqueous solvent. The aqueous solvent may be water, a water-soluble solvent, or a mixed solvent consisting of water and a water-soluble solvent.

Specific examples of water include natural water, purified water, distilled water, ion-exchanged water, pure water, and ultrapure water (eg, Milli-Q water).
Among these, from the viewpoint of having few impurities, purified water, distilled water, ion-exchanged water, pure water, or ultrapure water is preferable as water.

Examples of the water-soluble solvent include ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, and methyl isobutyl ketone; alcohols such as methanol, ethanol, 2-propanol, 2-methyl-1-propanol, 1-butanol, and 2-methoxyethanol; ethers such as tetrahydrofuran, 1,4-dioxane, and 1,2-dimethoxyethane; and amides such as dimethylformamide and N-methylpyrrolidone. In particular, it is preferable to use a compound selected from the group consisting of ketones having 3 to 6 carbon atoms and alcohols having 1 to 5 carbon atoms.
Other water-soluble organic solvents that can be dissolved in water can also be used. For example, glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycol, and polypropylene glycol; diols such as butanediol, pentanediol, hexanediol, and diols of the same family; glycol esters such as propylene glycol laurate; glycol ethers such as cellosolves including diethylene glycol monoethyl, diethylene glycol monobutyl, and diethylene glycol monohexyl ethers, propylene glycol ether, dipropylene glycol ether, and triethylene glycol ether; alcohols such as methanol, ethanol, isopropyl alcohol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, butyl alcohol, pentyl alcohol, and alcohols of the same family; or sulfolane; lactones such as γ-butyrolactone; lactams such as N-(2-hydroxyethyl)pyrrolidone; glycerin and its derivatives, polyoxyethylene benzyl alcohol ether, and various other solvents known as water-soluble organic solvents can be mentioned. These water-soluble organic solvents can be used alone or in combination of two or more.
Among these, polyhydric alcohols such as glycols and diols, which have a high boiling point, low volatility and high surface tension, are preferred, and glycols such as diethylene glycol and triethylene glycol are particularly preferred.

The formulation of the cosmetic is not particularly limited and may be any of liquid, emulsion, gel, cream, solid, paste, powder, etc. In the case of a liquid, it may be any of emulsion systems such as water-based, oil-in-water emulsion, water-in-oil emulsion, etc.

<Method of producing pigment composition>
The pigment composition of the present invention comprises
A step of mixing the pigment (A), the sulfosuccinic acid compound (B) and an aqueous solvent, and stirring and dispersing the resulting aqueous mixture (hereinafter, sometimes referred to as "step 1"); and
The method includes a step of disintegrating the stirred aqueous mixture using a wet disperser (hereinafter, sometimes referred to as "step 2").

[Step 1]
In step 1, the pigment (A), the sulfosuccinic acid compound (B), and the aqueous solvent are mixed, and the resulting aqueous mixture is stirred to disperse each component in the aqueous mixture. The pigment (A), the sulfosuccinic acid compound (B), and the aqueous solvent in step 1 are the same as the above-mentioned component (A), component (B), and aqueous solvent, respectively.
In the present invention, the term "stirring" refers to mixing substances to mix multiple types of substances. Specifically, it refers to a process of mixing multiple types of substances and the aqueous solvent by stirring component (A), component (B), an aqueous solvent, and other optional components in a stirrer.
The stirrer is not particularly limited as long as it can achieve the effects of the present invention and can be appropriately selected depending on the purpose, and examples thereof include simple stirrers such as a homodisper, emulsifier, line mixer, three-one motor, magnetic stirrer, etc., and media dispersers such as a sand mill, bead mill, pebble mill, ball mill, pearl mill, basket mill, attritor, dyno mill, bore mill, visco mill, motor mill, SC mill, dry mill, paint conditioner, etc. In addition, it is also possible to use media-less dispersers that do not use media, such as ultrasonic dispersers (ultrasonic homogenizers), high-pressure homogenizers, nanomizers, ultimizers, etc., roll mills such as three-rolls, Henschel mixers, pressure kneaders, intensive mixers, Banbury mixers, planetary mixers, etc.

The conditions in step 1 are not particularly limited and can be appropriately selected depending on the purpose as long as the effects of the present invention are achieved. For example, the stirring time is preferably 0.5 to 48 hours. The temperature during stirring is preferably 10 to 80°C.

[Step 2]
In step 2, the aqueous mixture stirred in step 1 is disintegrated using a wet disperser.
In the present invention, "disintegration" refers to a process of reducing the particle size by applying mechanical energy such as impact force or shear force to aggregates such as aggregated particles to break the bonds between the components that make up the aggregates. For example, when components in an aqueous mixture (e.g., component (A), an aggregate of components (A) and (B), or component (A) coated with component (B)) are aggregated, disintegration refers to breaking down these aggregated components (aggregated particles) to a size close to the primary particle size, that is, converting them into primary particles.
By crushing, the particle size of the component (A) can be mainly reduced, and the smaller particles of the component (A) can be dispersed in the aqueous solvent.

The disintegrator is not particularly limited as long as it can achieve the effects of the present invention, and can be appropriately selected depending on the purpose. For example, it can be a type that utilizes shear force due to mechanical stirring, or a type that utilizes a force generated by a pressure change, a flow path change, or a collision of a flux of the treated liquid supplied at high speed.
More specifically, examples of the disintegrator include Starburst, Microfluidizer, Nanomizer, and the like.

The conditions in step 2 are not particularly limited and can be appropriately selected depending on the purpose as long as the effects of the present invention are achieved. For example, the crushing time is preferably 1 to 24 hours.
The temperature during the disintegration is preferably 1 to 80°C.
The pressure during disintegration is preferably 100 to 250 MPa, and more preferably 225 to 250 MPa.
The number of passes during crushing is preferably 1 to 100, and more preferably 25 to 75.
The volume average diameter of the particles containing components (A) and (B) after crushing is preferably 100 to 2500 nm, more preferably 100 to 1000 nm, and even more preferably 120 to 180 nm.
The volume average diameter can be measured using "MT3300II" (manufactured by Microtrac Bell).

In steps 1 and 2, various conditions such as the type and size (volume) of the equipment, the type and amount of the stirred and crushed sample (component (A), component (B), and other components), and the flow rate of the stirred and crushed sample are set appropriately.

By going through steps 1 and 2, at least a portion of the surface of component (A) (preferably 30% or more of the surface area, more preferably 50% or more, and even more preferably 80% or more) is covered with component (B).
After step 2, other components may be added and mixed so that the other components are contained in the component (A) coated with the component (B). As the other components, the above-mentioned reactive gelling agent is preferable.
In producing the pigment composition of the present invention, the amount of the reactive gelling agent used is preferably 1 to 45 parts by mass, more preferably 5 to 35 parts by mass, and even more preferably 10 to 25 parts by mass, per 100 parts by mass of the component (A).
The amount of the ionic crosslinking agent used is preferably 10 to 70 parts by mass, more preferably 20 to 60 parts by mass, and even more preferably 30 to 50 parts by mass, based on 100 parts by mass of the reactive gelling agent.
It is more preferable that the volume average diameter of particles containing components (A) and (B) and a constitutional unit derived from the gelling agent (structure derived from alginic acid) when treated with a reactive gelling agent is 15 to 25 μm.
The volume average diameter can be measured using "MT3300II" (manufactured by Microtrac Bell).
Furthermore, a drying step may be provided as an optional step after step 2, in which most of the aqueous solvent is distilled off to obtain a solid or wet cake pigment composition. Drying can be performed by heating using a known method or using a commercially available dryer.
Furthermore, a pulverization step may be carried out after the drying step. By pulverization, the solid or wet cake can be converted into powder, and made into a form that is easy to use in cosmetics.

The present invention will be described in further detail below with reference to examples, but the present invention is not limited to these examples.

Example 1
(Production of Surface-Treated Powder (1))
Two 1-L plastic bottles were charged with 33.0 g of a 50% by mass solution of di-2-ethylhexyl sodium sulfosuccinate (manufactured by Tokyo Chemical Industry Co., Ltd.) in isopropyl alcohol, 38.5 g of isopropyl alcohol, 451.0 g of ion-exchanged water, and 110.0 g of "C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical Corporation), and 10.0 g of φ3.0 mm glass beads were added and stirred with a paint conditioner at 30° C. for 1 hour.
After stirring, the slurry from which the glass beads had been separated was combined, and the concentration was adjusted with ion-exchanged water so that the non-volatile content was 15.0% by mass. The mixture was then dispersed in a Starburst (manufactured by Sugino Machine Co., Ltd.) at a temperature of 30° C. and a pressure of 245 MPa for 50 passes, and the slurry remaining in the passage was pushed out with 300.0 g of ion-exchanged water to obtain 1646.8 g of a slurry with a non-volatile content of 14.1% by mass and a volume average diameter of 132 nm. The volume average diameter was measured with a “Nanotrack WAVE II” (manufactured by Microtrack Bell Co., Ltd.).
The obtained slurry was heated to 100°C, and the solvent and part of the water contained therein were distilled off (844.6 g). The obtained wet cake was dried in a box dryer (90°C) and then pulverized in a juicer to obtain surface-treated powder (1).

Example 2
(Production of Surface-Treated Powder (2))
Two 1-L plastic bottles were charged with 36.0 g of a 50% by mass solution of di-2-ethylhexyl sodium sulfosuccinate (manufactured by Tokyo Chemical Industry Co., Ltd.) in isopropyl alcohol, 27.0 g of isopropyl alcohol, 386.0 g of ion-exchanged water, and 90.0 g of "C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical Co.), and 10.0 g of φ3.0 mm glass beads were added and stirred with a paint conditioner at 30° C. for 1 hour.
After stirring, the slurry from which the glass beads had been separated was combined, and the concentration was adjusted with ion-exchanged water so that the non-volatile content was 15.0% by mass, and then the mixture was dispersed in a Starburst (manufactured by Sugino Machine Co., Ltd.) for 50 passes at a pressure of 245 MPa under a temperature condition of 30° C. to obtain a slurry with a non-volatile content of 14.1% by mass and a volume average diameter of 140 nm. Ion-exchanged water was added to the slurry to adjust the non-volatile content to 10% by mass, and the mixture was heated to 100° C. to distill off a portion of the solvent and water contained therein (390.0 g), to obtain a slurry with a non-volatile content of 11.4% by mass and a volume average diameter of 154 nm.
Under stirring conditions, 330.5 g of a 5% by weight aqueous solution of sodium alginate (Kimica Algin ULV-L3, manufactured by Kimica) was added to the obtained slurry, and 999.4 g of ion-exchanged water was added so that the non-volatile content became 7.0% by weight. 1899.3 g of a 0.35% by weight aqueous solution _of CaCl2 was added dropwise to the slurry over about 2 hours to obtain a slurry with a volume average diameter of 20.6 μm. The volume average diameter was measured using "MT3300II" (manufactured by Microtrack Bell).
The slurry was filtered with hard filter paper No. 4A (manufactured by Advantec Co., Ltd.) and washed with ion-exchanged water until the specific conductivity became 63 μS/m to obtain a wet cake, which was then dried (90° C.) in a box dryer and pulverized with a juicer to obtain a surface-treated powder (2).

<Examples 3 to 4, Comparative Example 1>
(Preparation of Liquid Cosmetics)
Using the surface-treated powders (1) and (2) obtained in Examples 1 and 2 above, or untreated carbon black ("C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical Corporation)), the pigment powder, glycerin, and ion-exchanged water were charged in the formulation shown in Table 1 so that the pigment content was 3.0% by mass, and the mixture was stirred (2000 rpm) for 30 minutes in a Dispermat (CV3-PLUS manufactured by Eiko Seiki Co., Ltd.), to prepare the liquid cosmetic preparations of each example.

(Affinity Evaluation)
To evaluate the affinity with aqueous solvents, the absorbance at 550 nm was measured using the liquid cosmetic immediately after preparation and after being left to stand for 24 hours, and the absorbance change rate was calculated from the numerical value obtained by dividing the absorbance after being left to stand for 24 hours by the absorbance immediately after preparation.
Specifically, the supernatant of each liquid cosmetic was collected, ion-exchanged water was added so that the pigment content was 0.002% by mass, and the absorbance at 550 nm was measured using a double-beam spectrophotometer "U-2910" (manufactured by Hitachi High-Tech Science Corporation). The results are shown in Table 2.

From the above results, it was confirmed that the cosmetics of Examples 3 and 4, which used the pigment composition of the present invention, had high affinity with aqueous solvents, while the cosmetic of Comparative Example 1, which did not contain component (B), had poor affinity with aqueous solvents.

Example 5
Surface-treated powder (3) was obtained in the same manner as in Example 1, except that "C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical Co.) was replaced with "C47-5002 SUNPURO TITANIUM OXIDE" (titanium oxide manufactured by Sun Chemical Co.). The volume average particle size of the slurry obtained after crushing was 890.9 nm.

Example 6
Surface-treated powder (4) was obtained in the same manner as in Example 1, except that "C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical) was replaced with "C33-7011 SUNPURO BLACK IRON OX" (iron tetroxide manufactured by Sun Chemical). The volume average particle size of the slurry obtained after crushing was 2366.4 nm.

Example 7
Surface-treated powder (5) was obtained in the same manner as in Example 1, except that "C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical) was replaced with "C33-9001 SUNPURO FE OX" (iron oxyhydroxide manufactured by Sun Chemical). The volume average particle size of the slurry obtained after crushing was 828.5 nm.

Example 8
Surface-treated powder (6) was obtained in the same manner as in Example 1, except that "C47-2222 SunCROMA D&C Black 2" (carbon black manufactured by Sun Chemical Corporation) was replaced with "C33-8001 SUNPURO RED IRON" (iron trioxide manufactured by Sun Chemical Corporation). The volume average particle size of the slurry obtained after crushing was 1333.8 nm.

<Examples 9 to 12 and Comparative Examples 2 to 5>
(Preparation of Liquid Cosmetics)
Using the surface-treated powders (3) to (6) obtained in Examples 5 to 8 above, or the untreated pigment used to prepare them, the pigment powder, glycerin, and ion-exchanged water were charged in the formulations shown in Table 3 so that the pigment content was 3.0% by mass, and the mixture was stirred (2000 rpm) for 30 minutes in a Dispermat (CV3-PLUS, manufactured by Eiko Seiki Co., Ltd.), to prepare the liquid cosmetic preparations of each example.

(Affinity Evaluation)
To evaluate the affinity with aqueous solvents, the absorbance at 550 nm was measured using the liquid cosmetic immediately after preparation and after being left to stand for 24 hours, and the absorbance change rate was calculated from the numerical value obtained by dividing the absorbance after being left to stand for 24 hours by the absorbance immediately after preparation.
Specifically, the supernatant of each liquid cosmetic was collected, ion-exchanged water was added so that the pigment content was 0.002% by mass, and the absorbance at 550 nm was measured using a double-beam spectrophotometer "U-2910" (manufactured by Hitachi High-Tech Science Corporation). The results are shown in Table 4.

From the above results, it was confirmed that the cosmetics of Examples 9 to 12, which used the pigment composition of the present invention, had a higher absorbance change rate than the corresponding untreated pigments of Comparative Examples 2 to 5 that did not contain component (B), and therefore had a high affinity with aqueous solvents.

Claims (6)

A cosmetic pigment composition comprising a pigment (A) and a sulfosuccinic acid compound (B),
The pigment (A) contains an inorganic pigment selected from the group consisting of iron oxide (red (Fe ₂ O ₃ )) and red iron oxide,
The sulfosuccinic acid compound (B) contains sodium di-2-ethylhexyl sulfosuccinate,
the content of the sulfosuccinic acid compound (B) in the pigment composition is 5 to 35% by mass ,
A cosmetic pigment composition , wherein the content of the sulfosuccinic acid compound (B) is 10 to 30% by mass relative to the pigment (A) . The cosmetic pigment composition according to claim 1, wherein the sulfosuccinic acid compound (B) covers at least a portion of the surface of the pigment (A). The cosmetic pigment composition according to claim 1, further comprising a reactive gelling agent. A cosmetic comprising the cosmetic pigment composition according to any one of claims 1 to 3. The cosmetic according to claim 4, which is selected from the group consisting of makeup cosmetics, hair cosmetics, and suntan and sunscreen cosmetics. A step of mixing the pigment (A), the sulfosuccinic acid compound (B) and an aqueous solvent, and stirring the resulting aqueous mixture to disperse the pigment; and
A method for producing a cosmetic pigment composition, comprising a step of disintegrating the stirred aqueous mixture using a wet disperser,
The pigment (A) contains an inorganic pigment selected from the group consisting of iron oxide (red (Fe ₂ O ₃ )) and red iron oxide,
The sulfosuccinic acid compound (B) contains sodium di-2-ethylhexyl sulfosuccinate,
the content of the sulfosuccinic acid compound (B) in the pigment composition is 5 to 35% by mass ,
The content of the sulfosuccinic acid compound (B) is 10 to 30 mass % relative to the pigment (A) .