JP6661972B2 - Solid composition containing fine inorganic powder with hydrophobic organic surface treatment - Google Patents

Description

The present invention provides a solid composition comprising a fine particle inorganic powder treated with a hydrophobic organic surface, a polyhydric alcohol, and at least one or more nonionic surfactants, and having a water content of 5% by mass or less. About.

2. Description of the Related Art In recent years, sun care products have attracted attention due to an increase in awareness of ultraviolet rays. These use organic UV filters and inorganic UV filters, but there is a strong demand for inorganic UV filters in terms of safety, etc., and fine particles of inorganic powder such as titanium oxide, zinc oxide and cerium oxide are tanned. Suncut cosmetics formulated as an inhibitor have attracted attention.

Generally, as the suncut cosmetics as described above, W / O-based cosmetics in which an inorganic powder is blended in an oily medium are used. However, in recent years, O / W-based sun-cut cosmetics in which inorganic powder is blended with water have attracted attention due to the poor feel of the W / O-based cosmetics and the difficulty of cleansing. Was.

Many of current O / W cosmetics use a water-soluble polymer in an aqueous phase, and the stability as a cosmetic is maintained due to its structural viscosity. The above-mentioned water-soluble polymers include those having a carboxylic acid type and those having a sulfonic acid type, both of which have an anionic group in the structure of the polymer.

On the other hand, fine particle inorganic powders are subjected to surface treatment with inorganic compounds such as silica and alumina for the purpose of suppressing the surface activity of the particles, suppressing the elution of polyvalent metals and metal ions, and improving the hydrophilicity. I have. However, an inorganic powder whose outermost layer is an inorganic compound is not preferred because it produces a tingling sensation when blended into a cosmetic and has a poor feel. For example, in the case of fine particle titanium oxide, the surface activity of the fine particle titanium oxide is blocked by surface treatment with silica, and the hydrophilicity is improved by using the hydration ability of the silanol group of silica. When blended, the skin feels tingling between the preparation and the skin due to the strong cohesiveness of the silanol group, and the feel is poor. Further, it has poor water resistance to sweat and water. Further, when such a silica-treated titanium oxide is incorporated in a large amount into the O / W cosmetic containing the water-soluble polymer, the viscosity of the cosmetic increases or gels over time due to the effect of silanol groups. There was also the problem of getting up.

As a result, the fine inorganic powder can sufficiently exhibit the performance of the inorganic powder without agglomeration, and can be stably incorporated into O / W cosmetics containing a water-soluble polymer without causing a decrease in viscosity or gelation due to aggregation. There has been a demand for a cosmetic material that has both the ability to be used, the excellent feeling without a tingling sensation, and the excellent water resistance to sweat and water.

For example, Patent Document 1 discloses a dispersion in which an inorganic powder having a water-repellent organic surface treatment is dispersed in water, and a cosmetic using the dispersion, for the purpose of improving feel and improving dispersibility of the inorganic powder. The fee is stated. In general, since inorganic particles are strongly agglomerated primary particles, a dispersion obtained by dispersing the inorganic powder in the dispersion medium as described above is used as a material for cosmetics. Dispersions have high transport costs and have problems in stability such as settling during storage. Furthermore, the presence of the dispersion medium has a disadvantage that it is difficult to adjust the blending of the raw materials when producing the cosmetic.

WO2013 / 018827

The present invention has been made in view of the above problems, and has excellent stability and usability even when blended into an O / W cosmetic containing excellent water dispersibility and containing a water-soluble polymer. It is intended to provide a cosmetic material that can be used. Further, the present invention provides a material having excellent storage stability.

The present inventor has conducted intensive studies and found that a predetermined amount of a mixed liquid of a specific nonionic surfactant and a polyhydric alcohol is blended with a hydrophobic organic surface-treated fine inorganic powder without blending water. As a result, they have found that they have good storage stability and have excellent stability and feeling of use when incorporated into cosmetics.

That is, the present invention includes a hydrophobic inorganic surface-treated fine particle inorganic powder , a polyhydric alcohol that is 1,3-butylene glycol, and a nonionic surfactant that is an organopolysiloxane having a polyoxyalkylene group. A composition having a water content of 5% by mass or less, wherein the composition contains at least 40% by mass of the fine particle inorganic powder, and the nonionic surfactant has a concentration of 20% by mass in 1,3-butylene glycol. When mixed at 35 ° C., the mixture is transparently dissolved and / or slightly turbid at 35 ° C., and the mixture of the polyhydric alcohol and the nonionic surfactant is liquid at 25 ° C., and the amount of the mixture (ml) is Blended in the composition in an amount that is 0.5 to 3 times the multiplier (ml) of the powder oil absorption (ml / g) and the powder blending amount (g) measured in the mixed solution;
The fine particle inorganic powder is a solid composition in which a part or the entire surface is coated with at least one selected from the group consisting of silica, aluminum hydroxide, alumina and zirconia.

The fine inorganic powder is preferably at least one selected from the group consisting of titanium oxide, zinc oxide and cerium oxide .

The polyhydric alcohol is preferably one or more polyhydric alcohols selected from the group consisting of propylene glycol, butylene glycol, pentanediol, dipropylene glycol, hexanediol and heptanediol. The nonionic surfactant is preferably insoluble or cloudy at 35 ° C. when mixed with water at 20% by mass. The nonionic activator is preferably an organopolysiloxane-based nonionic activator.

The present invention is characterized in that at least one kind of nonionic surfactant, hydrophobic organic surface-treated fine particle inorganic powder, and fine particle inorganic powder containing polyhydric alcohol are blended in a blending amount of 40% by mass or more. It is a solid composition. This composition, unlike liquid dispersions, does not cause settling on storage. Further, when this composition is blended with an O / W cosmetic using an anionic water-soluble polymer, the cosmetic has excellent quality without causing problems such as a decrease in viscosity and gelation, and a feeling of tingling and the like. It is possible to obtain a cosmetic which is excellent in usability such as water repellency and the like. Further, it is easily dispersed in water without using a special dispersing machine such as a bead mill, and is easily incorporated into cosmetics and paints.

As the primary particle size of the fine particle inorganic powder used in the present invention, it is generally preferable that the average particle size having an ultraviolet absorbing / scattering effect is 5 to 200 nm. The lower limit is more preferably 10 nm, and the upper limit is preferably 100 nm. The particle diameter in the present specification is a value measured by a method of measuring the particle diameter of 200 particles randomly selected with an electron microscope and calculating the average of the primary particle diameter.

The fine particle inorganic powder is not particularly limited, and includes, for example, titanium oxide, zinc oxide, and cerium oxide, and may be used in combination of two or more, or may be a composite.

As the shape of the fine particle inorganic powder, any shape such as a sphere, a rod, a needle, a spindle, a plate, a hexagonal plate, and a needle aggregate can be used. In the case of rod-like, needle-like, or spindle-like particles, the above average particle diameter is defined by the length on the short axis side, and in the case of plate-like, the average diameter of the largest inscribed circle of the surface is defined.

Further, it is preferable that these fine-particle inorganic powders are coated with another inorganic compound and subjected to a hydrophobic organic surface treatment on a composite powder in which the surface activity of titanium oxide, zinc oxide and cerium oxide is blocked. . The surface-treated inorganic compound includes one or more of silica, aluminum hydroxide, alumina, and zirconia. The coating amount is preferably from 1 to 25% by mass, more preferably from 2 to 20% by mass, based on the total amount of the inorganic powder after the treatment. In the case of using a material that dissociates in water to generate polyvalent metal ions, such as aluminum hydroxide, aluminum ions are eluted into the aqueous system when blended into a cosmetic containing a water-soluble polymer, and anionic water Since the conductive polymer causes a decrease in viscosity, the amount used is limited and is preferably 10% by mass or less. Further, from such a viewpoint, silica or the like which does not cause ion elution is preferable.

Examples of the hydrophobic organic surface treating agent for the fine inorganic powder include methyl hydrogen siloxane polysiloxane, a copolymer of methyl hydrogen polysiloxane and dimethyl polysiloxane, and reactive trialkoxysilyl such as trimethoxysilyl group and triethoxysilyl group. Examples include group-containing dimethylpolysiloxane, alkyl group-modified polysiloxane containing the same reactive group, dimethylpolysiloxane, alkylsilane, alkyl titanate, and metal soap. At least one compound can be treated by a known method. By being treated with these hydrophobic organic surface treatment agents, the hydrophilic groups of the coated inorganic material are blocked, and when blended in a cosmetic containing a water-soluble polymer, a gel of the inorganic powder and the water-soluble polymer is formed. The formation is inhibited, and the feeling of blemishes during use can be eliminated, and the water resistance can be improved.

In the hydrophobic organic treatment of the inorganic powder, the organic powder is preferably subjected to an organic treatment of 2 to 15% by mass based on the total amount of the inorganic powder after the treatment. The hydrophobicity is insufficient, and at 15% by mass or more, the hydrophobicity reaches a peak. More preferably, an organic treatment of 4 to 12% by mass is performed.

The solid composition contains the inorganic powder in an amount of 40% by mass or more based on the total amount of the composition. It is preferable to use the compounding amount in that the amount necessary for the effect can be compounded in a small amount as the cosmetic material. The amount of the inorganic powder in the composition is more preferably 60% by mass or more. The upper limit of the amount is not particularly limited, but is preferably 95% by mass or less, more preferably 90% by mass or less.

The solid composition of the present invention contains a polyhydric alcohol. The polyhydric alcohol is preferably one or more selected from propylene glycol, butylene glycol, pentanediol, dipropylene glycol, hexanediol, and heptanediol, particularly, butylene glycol, pentanediol, and dipropylene glycol. , Hexanediol is preferred. This polyhydric alcohol is preferably contained in the solid composition at 2 to 30% by mass. The lower limit is more preferably 5% by mass, and the upper limit is more preferably 25% by mass. It is considered that the incorporation of such a polyhydric alcohol allows the nonionic surfactant to be more uniformly oriented on the powder surface and stabilizes the formulation system when the cosmetic is incorporated.

The solid composition of the present invention contains a nonionic surfactant. The nonionic surfactant may be used alone or in combination of two or more. When mixed with 1,3-butylene glycol at a concentration of 20% by mass, the above nonionic surfactant is a nonionic surfactant which is transparently dissolved or slightly turbid at 35 ° C. In the case of a paste to a solid, the mixture is heated to be uniform and then set at 35 ° C.). When two or more types of nonionic surfactants are used in combination, when the above-described test is performed on the nonionic surfactants mixed at a mixing ratio to be blended in the solid composition, the composition is transparent. It needs to be dissolved or turbid.

In the present specification, “transparent dissolution” means that the haze value at an optical path length of 10 mm at 35 ° C. of the obtained mixed solution is less than 10, and “finely turbid” means that the obtained mixed solution has a haze value of less than 35. It means that the haze value at an optical path length of 10 mm at 10 ° C. is 10 or more and the total light transmittance is 30% or more.

By using such a nonionic surfactant, an effect that a layer made of the nonionic surfactant can be efficiently formed on the particle surface is obtained. The amount of the nonionic surfactant is preferably 1 to 30% by mass based on the total amount of the solid composition. The lower limit is more preferably 2% by mass, and still more preferably 3% by mass. The upper limit is 25% by mass.
Is more preferable, and even more preferably 20% by mass.

Further, the above nonionic surfactant is a nonionic surfactant which is insoluble or cloudy at 35 ° C. when mixed with water at a concentration of 20% by mass (the nonionic surfactant is a paste-solid at room temperature). In this case, it is more preferable that the temperature is uniformed by heating and then 35 ° C.). By using such a nonionic surfactant, the dispersibility in water at the time of preparation of the cosmetic is increased, and the feel and stability of the obtained cosmetic can be further improved. When two or more nonionic surfactants are used in combination, the nonionic surfactants mixed at a mixing ratio to be mixed in the solid composition are insoluble when the above-described test is performed. Or it needs to be clouded.

In addition, in this specification, "insoluble" means a state in which undissolved residue is produced even when mixed, or a phase is separated after 1 hour even if it appears turbid. "White turbidity" means that the obtained mixture has a haze value of 10 or more at an optical path length of 10 mm at 35 ° C. and a total light transmittance of less than 30%.

The HLB of such a surfactant is desirably 6 or more and 12 or less. When a solid composition using only a nonionic surfactant having an HLB of more than 12 is mixed into an O / W cosmetic, the solubility of the nonionic surfactant in water is too high, so that the composition becomes powder. Of O / W type cosmetics tends to increase, and water resistance tends to deteriorate. When the HLB of the nonionic surfactant is less than 6, a solid composition having poor dispersibility in water is produced. Note that, in this specification, HLB is defined as W.W. C. It is determined by the following equation defined by Griffin. _NHLB = (E + P) / 5 ( _NHLB : HLB value, E: mass% of polyoxyethylene part based on the whole dispersant molecule, P: mass% of polyhydric alcohol part based on the whole dispersant molecule)

Examples of the nonionic surfactant include polyoxyalkylene alkyl ether, polyoxyalkylene fatty acid ester, polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene castor oil, polyoxyalkylene hardened castor oil, polyoxyalkylene sorbitol tetrafatty acid ester Glycerin fatty acid ester, sorbitan fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, organopolysiloxane having a polyoxyalkylene group, organopolysiloxane having a polyglycerin group, and organopolysiloxane having a sugar chain.

Among them, it is preferable to use a polyoxyalkylene fatty acid ester, a polyoxyalkylene sorbitan fatty acid ester, or an organopolysiloxane having a polyoxyalkylene group as the nonionic surfactant.

Further, the above-mentioned organopolysiloxane-based nonionic surfactants are most preferable, and when an organopolysiloxane-based nonionic surfactant is used, the stability of the composition and the use when used in cosmetics are considered. Particularly excellent effects can be obtained in terms of feeling and the like.

The total amount of the mixed liquid of the polyhydric alcohol and the nonionic surfactant is determined by calculating the oil absorption (ml / g) of the powder measured with the mixed liquid of the polyhydric alcohol and the nonionic surfactant to be mixed and the powder. The compound is preferably incorporated into the solid composition in an amount that is 0.5 to 3 times the multiplier (ml) of the compounding amount (g), and more preferably 1 to 2 times. If the amount is less than this amount, it is difficult to incorporate the compound into the aqueous phase of the cosmetic, and if the amount is more than this amount, the oil emerges from the solid composition and the solid composition becomes non-uniform. appear. The oil absorption is a value measured by a method described in Examples described later.

The solid composition of the present invention is not limited in its production method, but a polyhydric alcohol, a nonionic surfactant and a hydrophobic organic surface-treated inorganic powder are treated with a blade type mixer, a cone mixer, It can be obtained by mixing using a kneader, a twin-screw kneader, a roll machine, a granulator or the like. The polyhydric alcohol and the nonionic surfactant may be mixed in advance, and the inorganic powder may be added to and mixed with the obtained mixed solution, or the polyhydric alcohol, the nonionic surfactant and the inorganic powder may be mixed. The bodies may be added simultaneously and mixed. The solid composition obtained by mixing may be formed into granules, noodles, or the like, if necessary.

In the solid composition of the present invention, if necessary within the range that does not impair the performance of the composition, alkyl paraoxybenzoate, benzoic acid, sodium benzoate, sorbic acid, potassium sorbate, phenoxyethanol, salicylic acid, phenolic acid, A bactericidal antiseptic such as sorbic acid, parachloromethcresol, hexachlorophen, benzalkonium chloride, chlorhexidine, photosensitizer, and phenoxyethanol, and an antibacterial agent can be added.

The solid composition of the present invention is a solid composition having a water content of 5% by mass or less. The water content is a value measured by a method described in Examples described later. The upper limit is preferably 5% by mass or less, more preferably 2% by mass or less. If the water content is more than 5% by mass, the stability during storage deteriorates, which is not preferable.

The solid composition of the fine inorganic powder subjected to the hydrophobic organic surface treatment thus obtained is useful as a component for preparing a cosmetic having an ultraviolet blocking effect. In this case, only the solid composition of the present invention may be used as an ultraviolet ray blocking component, but an oil-based dispersion of fine inorganic powder or an organic ultraviolet absorbent may be used in combination.

Further, the solid composition of the fine inorganic powder having been subjected to the hydrophobic organic surface treatment thus obtained may be used for a water-based paint or the like. Since the solid composition of the present invention can be easily dispersed in water using only a stirrer, there is an advantage that an expensive disperser such as a bead mill is not required.

Furthermore, the solid composition of the present invention can be particularly suitably used in the formulation of cosmetics used in combination with an anionic water-soluble polymer. That is, the use of the solid composition of the present invention has an advantage that the viscosity does not decrease or gelation does not occur even when used in combination with an anionic water-soluble polymer. Examples of such an anionic water-soluble polymer include a carboxyvinyl polymer.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to only these Examples. Unless otherwise specified, “%” described below means “% by mass”.

In Tables 1 and 2, the mixed liquid amount, oil absorption amount, powder compounding amount, particle size distribution D10, D50, D90, water content and storage stability are values obtained as follows.

The amount of the mixture refers to the weight and volume of the mixture of the polyhydric alcohol and the nonionic surfactant at 25 ° C.

The oil absorption is a value obtained by a method according to JIS K5101 using a mixed solution of a polyhydric alcohol and a nonionic surfactant mixed at the same ratio as when blended as a measurement oil.

The powder blending amount is the total weight of the powder used in the treatment.

The particle size distributions D10, D50, and D90 are obtained by adding 50 g of water to 50 g of the composition obtained in each of Examples and Comparative Examples, and measuring the particle size distribution when repulping with a stirrer. , And represent the integrated diameters of 10 wt%, 50 wt%, and 90 wt%, respectively. The measurement liquid used was one obtained by diluting the repulping liquid with water to such an extent that it could be measured by a particle size distribution analyzer.

The moisture content is obtained by heating 0.2 g of the solid compositions obtained in Examples and Comparative Examples using a moisture vaporizer at 150 ° C. for 10 minutes, and automatically measuring the moisture content (AQL-6A manufactured by Hiranuma Sangyo Co., Ltd.). )).

The storage stability is an evaluation of whether the compositions obtained in Examples and Comparative Examples were left at room temperature for one week to separate oil and powder or liquid components. If there is no change, it is regarded as good.

(Example 1) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5% by mass of silica and 6% by mass of silicone based on the total amount of surface-treated zinc oxide) and polyether A mixture of 750 g of a modified silicone (KF-6013: Shin-Etsu Chemical Co., Ltd.) (250 g) and 1,3-butylene glycol (500 g) was charged into a blade-type mixer, and mixed at 1000 rpm for 30 minutes. The resulting composition was a clay-like solid. The hardness of the composition was measured with a Yamanaka-type soil hardness meter, and was 1.6 kg / cm ² . The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition had a high dispersibility of the inorganic powder and was excellent in storage stability. When 2.0 g of polyether-modified silicone (KF-6013), which is the above-mentioned nonionic surfactant used at 35 ° C., is mixed with 8.0 g of 1,3-butylene glycol, the mixture becomes slightly turbid and 8.0 g of water is mixed. When it was mixed, it became cloudy.

(Example 2) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5 mass% silica, 4 mass% silicone based on the total amount of surface-treated zinc oxide) and polyether-modified silicone (KF-6013: manufactured by Shin-Etsu Chemical Co., Ltd.) 750 g of a mixed solution of 250 g of 1,3-butylene glycol and 500 g was charged into a blade-type mixer and mixed at 300 rpm for 10 minutes. The resulting composition was a flake-like solid. The oil absorption of the powder in the mixed liquid used was 0.18 ml / g, and (oil absorption) × (powder blending amount) was 540 ml. The obtained solid composition had a high dispersibility of the inorganic powder and was excellent in storage stability.

(Example 3) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5 mass% of silica and 6 mass% of silicone based on the total amount of surface-treated zinc oxide) and polyether A mixed solution (420 g) of modified silicone (KF-6013: Shin-Etsu Chemical Co., Ltd.) (140 g) and 1,3-butylene glycol (280 g) was charged into a blade-type mixer and mixed at 1000 rpm for 30 minutes. The resulting composition was a powder-like solid. The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition had a high dispersibility of the inorganic powder and was excellent in storage stability.

(Example 4) 2 kg of titanium oxide surface-treated with silica and silicone (particle size: 15 nm, surface treatment amount: 20% by mass of silica and 8% by mass of silicone based on the total amount of surface-treated titanium oxide) and polyether 1 kg of a mixed solution of 480 g of modified silicone (KF-6013: manufactured by Shin-Etsu Chemical Co., Ltd.) and 520 g of 1,3-butylene glycol was charged into a blade-type mixer and mixed at 300 rpm for 20 minutes. The resulting composition was a flake-like solid. The oil absorption of the powder in the mixed liquid used was 0.32 ml / g, and (oil absorption) × (powder blending amount) was 640 ml. The obtained solid composition had a high dispersibility of the inorganic powder and was excellent in storage stability.

(Example 5) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5% by mass of silica and 6% by mass of silicone based on the total amount of surface-treated zinc oxide) and polyether 1200 g of a mixed solution of 400 g of modified silicone (KF-6013: manufactured by Shin-Etsu Chemical Co., Ltd.) and 800 g of 1,3-butylene glycol was charged into a blade-type mixer and mixed at 1000 rpm for 30 minutes. The resulting composition was a clay-like solid. The hardness of the composition was measured with a Yamanaka-type soil hardness meter, and was found to be 1.0 kg / cm ² . The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition had a high dispersibility of the inorganic powder and was excellent in storage stability.

(Example 6) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5% by mass of silica and 4% by mass of silicone based on the total amount of surface-treated zinc oxide) and polyether A mixed solution of 750 g of a modified silicone (KF-6011: Shin-Etsu Chemical Co., Ltd.) (250 g) and 1,3-butylene glycol (500 g) was charged into a blade-type mixer and mixed at 1000 rpm for 30 minutes. The resulting composition was a clay-like solid. The oil absorption of the powder in the mixed solution used was 0.18 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition had a high dispersibility of the inorganic powder and was excellent in storage stability. When 2.0 g of polyether-modified silicone (KF-6011), which is the nonionic surfactant used at 35 ° C., is mixed with 8.0 g of 1,3-butylene glycol, the mixture becomes slightly turbid and 8.0 g of water. Was transparent when mixed with

(Comparative Example 1) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5% by mass of silica and 6% by mass of silicone based on the total surface-treated zinc oxide) and polyether A mixed solution (210 g) of modified silicone (KF-6013: Shin-Etsu Chemical Co., Ltd.) (80 g) and 1,3-butylene glycol (130 g) was charged into a blade-type mixer and mixed at 1000 rpm for 30 minutes. The resulting composition was a powder-like solid. The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition was a composition having poor dispersibility in water.

(Comparative Example 2) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5% by mass of silica and 6% by mass of silicone based on total surface-treated zinc oxide) and polyether A mixture of 2,700 g of a modified silicone (KF-6013: Shin-Etsu Chemical Co., Ltd.) (900 g) and 1,3-butylene glycol (1800 g) was charged into a blade-type mixer, and mixed at 1000 rpm for 30 minutes. The composition obtained was in the form of a paste. The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition was a composition in which inorganic powder and oil were separated and storage stability was poor.

(Comparative Example 3) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5% by mass of silica and 6% by mass of silicone based on the entire surface-treated zinc oxide) and polyether A mixed solution of 750 g of a modified silicone (KF-6017: Shin-Etsu Chemical Co., Ltd.) (250 g) and 1,3-butylene glycol (500 g) was charged into a blade-type mixer and mixed at 300 rpm for 30 minutes. The resulting composition was a flake-like solid. The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. The obtained solid composition did not disperse in water. When 2.0 g of polyether-modified silicone (KF-6017), which is the nonionic surfactant used at 35 ° C., is mixed with 8.0 g of 1,3-butylene glycol, it becomes cloudy and 8.0 g of water. Did not dissolve when mixed.

(Comparative Example 4) 3 kg of zinc oxide surface-treated with silica and silicone (particle diameter: 35 nm, surface treatment amount: 5 mass% silica and 6 mass% silicone based on the total surface-treated zinc oxide) and polyether 1875 g of a mixed solution of 625 g of modified silicone (KF-6013: manufactured by Shin-Etsu Chemical Co., Ltd.) and 1250 g of 1,3-butylene glycol was charged into a blade-type mixer and mixed at 300 rpm for 30 minutes. The resulting composition was a clay-like solid. The oil absorption of the powder in the used liquid mixture was 0.16 ml / g, and (oil absorption) × (powder blending amount) was 480 ml. At this time, the mixed liquid amount was 1858 ml, and the ratio obtained by dividing the mixed liquid amount by (oil absorption amount) × (powder compounding amount) was 3.87. When 5 g of water was added to 95 g of the obtained clay-like solid composition and kneaded, the mixture became a liquid having a viscosity of 5000 mPa · s, and after one week, a supernatant in which the liquid component and the powder were separated was generated, and storage stability was observed. Was a bad composition. The water content of the composition to which this water was added was 5.98%.

When A ÷ B (mixed liquid amount ÷ (oil absorption amount) × (powder amount)) in Tables 1 and 2 is in the range of 0.5 to 3, it is finely dispersed in water, has a high degree of dispersion, and is stable in storage. Also excellent in nature. On the other hand, Comparative Example 1, which was out of the range, was a composition having poor dispersibility in water. Further, in Comparative Example 2, which was also out of the range, no solid composition was obtained, and the oil and powder were separated and non-uniform, resulting in poor storage stability. In Comparative Example 3, in which a non-ionic surfactant that becomes cloudy was used in 1,3-butylene glycol, water dispersion was not possible, and the particle size distribution could not be measured. Further, in Comparative Example 4 in which the water content was 5% by mass or more, the oil and the powder were separated and became non-uniform, resulting in poor storage stability. The results of this study were for a simple water-only system, but similar trends were observed for cosmetics and paints.

[Comparison of Nonionic Surfactant Type and Water Dispersibility] Example 1 (using KF-6013 as a nonionic surfactant) and Example 6 (KF-6011 as a nonionic surfactant) ) Was compared in water dispersibility. 20 g of water was added to 80 g of the solid composition obtained in Example 1 and Example 6, and mixed with a stirrer. When the state of the obtained mixture was confirmed, the mixture of Example 1 and water had a viscosity of 8220 mPa · s, whereas the mixture of Example 6 and water had poor fluidity in a clay-like state. The viscosity could not be measured. The above viscosity is a value measured by a B-type viscometer (manufactured by Tokyo Keiki). Therefore, it was found that Example 1 had better dispersibility in water than Example 6. That is, when mixed with water at a concentration of 20% by mass, a nonionic surfactant which is insoluble or cloudy at 35 ° C. (when the nonionic surfactant is a paste or solid at room temperature, it is heated to be uniform. After that, the temperature was confirmed at 35 ° C.), and it was found that the solid composition containing the nonionic surfactant was more excellent in dispersibility in water.

[Examples 7 to 12 and Comparative Examples 5 to 8] Using the obtained solid compositions of Examples 1 to 6 and Comparative Examples 1 to 4, Examples 7 to 12 and Comparative Example 5 having the following compositions were used. -8 sunscreen O / W creams were prepared with the formulations shown in Table 3 and evaluated for quality. The amounts of the solid composition and water are adjusted as shown in Tables 4 and 5 in order to adjust the amount of the inorganic powder in the cosmetic to 16%.

(Production method) A: Components 1-4 are mixed and heated. B: Components 5 to 11 are uniformly mixed and heated. C: A was added to B, emulsified, and cooled to obtain respective sunscreen O / W creams (Examples 7 to 12, Comparative Examples 5 to 8).

The evaluation was performed as follows.
1. Stability of Sunscreen O / W Cream The sunscreen O / W cream adjusted in stability was allowed to stand at 50 ° C. for one month, and then it was confirmed whether or not thickening was observed.
[Evaluation criteria]
A: Not thickened.
：: Slightly thickened.
Δ: Thickened.
X: The gel is remarkably thickened to form a gel.
2. A use test was conducted by 20 expert evaluation panels to evaluate the spreadability during application, the lack of squeaky feeling on the back skin, and the sunscreen effect on a five-point scale based on the following criteria. did.
[Evaluation criteria]
5 points: Very good 4 points: Good 3 points: Normal 2 points: Somewhat bad 1 point: Bad [Judgment]
◎: average point 4.5 or more ○: average point 3.5 or more and less than 4.5 Δ: average point 2.5 or more and less than 3.5 x: average point less than 2.5 Overall rating ：: Both stability and usability are particularly excellent.
：: Both stability and usability are excellent.
Δ: Viscosity increases or inferior in use feeling.
×: Poor stability and poor feeling in use.

The sunscreen O / W creams containing the solid compositions obtained in Examples 1 to 6 were stable without change over time, and were also excellent in usability. On the other hand, the sunscreen O / W creams containing the solid compositions obtained in Comparative Examples 1 to 4 were not sufficient in terms of stability and feeling of use.

The solid composition of the present invention can be suitably used in the fields of cosmetics and paints.

Claims (3)

It contains a fine particle inorganic powder treated with a hydrophobic organic surface , a polyhydric alcohol which is 1,3-butylene glycol, and a nonionic surfactant which is an organopolysiloxane having a polyoxyalkylene group, and has a water content of Is 5% by mass or less, the composition contains 40% by mass or more of the fine particle inorganic powder, and the nonionic surfactant is mixed with 1,3-butylene glycol at a concentration of 20% by mass. It is transparently dissolved and / or slightly turbid at 35 ° C., and the mixture of the polyhydric alcohol and the nonionic surfactant is liquid at 25 ° C., and the amount (ml) of the mixture is measured in the mixture. Blended in the composition in an amount that is 0.5 to 3 times the multiplier (ml) of the oil absorption of the powder (ml / g) and the powder blending amount (g);
A solid composition in which the fine particle inorganic powder is partially or entirely coated with at least one selected from the group consisting of silica, aluminum hydroxide, alumina, and zirconia. The solid composition according to claim 1, wherein the fine particle inorganic powder is at least one selected from the group consisting of titanium oxide, zinc oxide, and cerium oxide. The solid composition according to claim 1, wherein the nonionic surfactant is insoluble or cloudy at 35 ° C. when mixed with water at 20% by mass.