JP7358815B2 - Liquid dispersion and its uses - Google Patents

Description

The present invention relates to liquid dispersions and their uses. More specifically, the present invention relates to a liquid dispersion containing a hydrophobized inorganic powder, a cosmetic raw material and a cosmetic using the same.

Inorganic powders are used in various applications as colorants, fillers, etc. For example, pigment grade titanium oxide, iron oxide, etc. are suitably used as coloring pigments in cosmetics and paints. It is known that these inorganic powders are used in the form of a dispersion in a dispersion medium in order to promote beautiful color development (for example, see Patent Document 1). In addition, since the surface of inorganic powder is hydrophilic, in order to exhibit water resistance against moisture such as sweat and rain, technology has been developed in which inorganic powder is surface-treated and then made into a dispersion (for example, patented (See references 2 to 4). However, none of these had sufficient stability when made into liquid dispersions.
On the other hand, a liquid dispersion in which a polyhydric alcohol and a nonionic surfactant are added to a hydrophobized inorganic powder has been developed as a stable liquid dispersion with excellent dispersion stability (Patent Document (see 5).

JP2012-097259A International Publication No. 2013/018827 pamphlet International Publication No. 2015/125622 pamphlet JP2016-74660A International Publication No. 2017/203846 pamphlet

The liquid dispersion described in Patent Document 5 can maintain a stable dispersion state for a long period of time, and can be suitably applied to both O/W type cosmetics and W/O type cosmetics. However, there was room for innovation in developing a liquid dispersion with even better dispersion stability that would not cause liquid floating or supernatant formation even when stored for a longer period of time.

The present invention has been made in view of the above-mentioned current situation, and it is an object of the present invention to provide a liquid dispersion that is particularly excellent in dispersion stability and does not cause floating or supernatant formation even when stored for a long period of time.

The present inventor investigated a liquid dispersion with particularly excellent dispersion stability that does not cause floating or supernatant formation even when stored for a long period of time, and developed a liquid dispersion that is treated with a polyhydric alcohol, a nonionic surfactant, and a hydrophobic treatment. In a liquid dispersion containing inorganic powder (referred to as hydrophobized inorganic powder), a polyalkylene glycol having a total carbon number of 4 to 30 is used as the polyhydric alcohol, and the hydrophobized inorganic powder is mixed in a predetermined proportion. By including the liquid dispersion, the viscosity immediately after preparation becomes appropriate and the dispersion state can be maintained stably for a long time, and the dispersion stability is maintained without floating or supernatant formation even when stored for a long period of time. The present inventors have discovered that this makes a particularly excellent liquid dispersion, and have completed the present invention.

That is, the present invention provides a liquid dispersion containing a polyalkylene glycol (A) having a total carbon number of 4 to 30, a nonionic surfactant (B), and a hydrophobized inorganic powder (C), This is a liquid dispersion characterized by containing 40% by weight or more of the hydrophobized inorganic powder (C) based on 100% by mass of the total amount of the dispersion.

The polyalkylene glycol is preferably hydrophilic.

The polyalkylene glycol is preferably at least one selected from polyethylene glycol and polypropylene glycol.

The mass ratio (A/B) of the polyalkylene glycol (A) having a total carbon number of 4 to 30 and the nonionic surfactant (B) is preferably 70 to 95/30 to 5.

The average particle diameter of the hydrophobized inorganic powder (C) is preferably 150 to 700 nm.

The hydrophobized inorganic powder (C) is an inorganic powder surface-treated with at least one member selected from the group consisting of silicone, alkylsilane, fatty acid (salt), amino acid (salt), and alkylphosphoric acid (salt). Preferably, it is a body.

The nonionic surfactant (B) is preferably a polyether-modified silicone.

The liquid dispersion preferably has a viscosity of 2,000 to 500,000 mPa·s at 25°C.

The present invention is also a cosmetic raw material characterized by comprising the liquid dispersion of the present invention.
The present invention is also a cosmetic product characterized by containing the liquid dispersion of the present invention.

The liquid dispersion of the present invention is a liquid dispersion with particularly excellent dispersion stability that does not cause floating or supernatant formation even when stored for a long period of time, so it can contribute to reducing the cost required for dispersion treatment. can. In addition, this liquid dispersion is particularly useful as a raw material for cosmetics, as it has good color development, feel, and handleability, and can provide highly water-repellent cosmetics that are resistant to sweat and water. It can be suitably applied to both cosmetics and W/O type cosmetics.

Preferred embodiments of the present invention will be specifically described below, but the present invention is not limited to the following description, and can be applied with appropriate modifications within the scope of the gist of the present invention.

The liquid dispersion of the present invention contains a polyalkylene glycol (A) having a total carbon number of 4 to 30, a nonionic surfactant (B), and a hydrophobized inorganic powder (C), and the total amount of the liquid dispersion is It is characterized by containing 40% by weight or more of the hydrophobized inorganic powder (C) based on 100% by weight.
The liquid dispersion of the present invention has an appropriate viscosity immediately after preparation, even when using hydrophobized inorganic powder with an average particle size of 150 nm or more, so it can be stably dispersed for a long time. condition can be maintained, and caking and phase separation over time can be sufficiently suppressed. Furthermore, by using polyalkylene glycol (A) having a total carbon number of 4 to 30, it becomes particularly excellent in dispersion stability without floating or forming a supernatant even when stored for a long period of time. Further, by using such polyalkylene glycol (A) having a total carbon number of 4 to 30, the effect of further reducing odor can also be obtained.
Each component contained in the liquid dispersion of the present invention will be explained below, and then the uses of the liquid dispersion of the present invention will be explained.

-Polyalkylene glycol (A) having a total carbon number of 4 to 30-
The polyalkylene glycol (A) having a total carbon number of 4 to 30 (hereinafter also simply referred to as "polyalkylene glycol") preferably has a total carbon number of 6 to 26. More preferably, the total number of carbon atoms is 8 to 20.
Here, the total carbon number is the value obtained by multiplying the carbon number of alkylene glycol, which is a structural unit of polyalkylene glycol, by the average repeating number of the structural unit.

The polyalkylene glycol is preferably hydrophilic in order to produce a liquid dispersion. Here, hydrophilicity means high solubility in water, and means that 0.5 g or more is dissolved in 1 ml of water.

Examples of the alkylene glycol serving as the structural unit of the polyalkylene glycol include alkylene glycols having 2 to 4 carbon atoms such as ethylene glycol, propylene glycol, and butylene glycol. Preferably, ethylene glycol or propylene glycol is used. That is, the polyalkylene glycol is preferably at least one selected from polyethylene glycol and polypropylene glycol.
In the above polyalkylene glycol, the average repeating number of the alkylene glycol serving as a structural unit is in the range of 2 to 15, and may be selected as appropriate depending on the number of carbon atoms in the alkylene glycol used, but it is preferably 3 to 13. preferable. More preferably, it is 4-10.

The content of the polyalkylene glycol (A) is preferably 10% by mass or more based on 100% by mass of the total amount of the liquid dispersion. This further improves the dispersion stability of the liquid dispersion. The content is more preferably 15% by mass or more, and still more preferably 20% by mass or more. Although the upper limit is not particularly limited, it is preferably 50% by mass or less in order to enhance the effects of other components. The content is more preferably 45% by mass or less, and still more preferably 40% by mass or less.

-Nonionic surfactant (B)-
The nonionic surfactant (B) is not particularly limited as long as it is a compound commonly used as a nonionic surfactant, and examples include polyether or its derivatives, polyether alkyl ether, and polyether. Oxyalkylene alkenyl phenyl ether, polyether fatty acid ester, sorbitan fatty acid ester, polyether sorbitan fatty acid ester, glycerin fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, polyether castor oil, polyether hydrogenated castor oil, polyether modified silicone , polyglycerin-modified silicone, and the like. Among these, it is preferable to use polyether fatty acid ester, polyether sorbitan fatty acid ester, and/or polyether-modified silicone. More preferably, at least polyether-modified silicone is used, which further improves the stability of the liquid dispersion and the feeling of use when used in cosmetics. Polyether-modified silicones are also suitable because of their high safety and thermal stability.

The nonionic surfactant (B) is also a compound that dissolves transparently or becomes slightly cloudy at 35°C when mixed with 1,3-butylene glycol at a concentration of 20% by mass (the nonionic surfactant dissolves slightly at room temperature). If it is in the form of a paste or solid, it is preferable to heat it to make it homogeneous and then check it at 35°C. This allows a layer of nonionic surfactant to be efficiently formed on the surface of the hydrophobized inorganic powder (C), thereby further improving the dispersion stability of the liquid dispersion.
When using a combination of two or more types of nonionic surfactants, when the above-mentioned test is performed on the nonionic surfactants mixed at the mixing ratio to be incorporated into the liquid dispersion, clear dissolution is observed. Alternatively, it is preferable that the liquid be slightly cloudy.

The nonionic surfactant (B) is a compound that becomes insoluble or cloudy at 35°C when mixed with water at a concentration of 20% by mass (if the nonionic surfactant is in the form of a paste to a solid at room temperature) It is also preferable to heat the mixture to make it uniform and then check the temperature at 35°C. As a result, when blended into cosmetics as a cosmetic raw material, the resulting cosmetics have better water resistance without impairing their dispersibility in water.
In addition, when using two or more types of nonionic surfactants in combination, when the above-mentioned test is conducted on the nonionic surfactants mixed at the mixing ratio to be incorporated into the liquid dispersion, no insoluble or It is preferable that it be cloudy.

In this specification, "transparent dissolution" means that the obtained mixed solution has a haze value of less than 10 at an optical path length of 10 mm at 35°C, and "slightly cloudy" means that the obtained mixed solution has a haze value of less than 10. It means a state in which the haze value at an optical path length of 10 mm at °C is 10 or more and the total light transmittance is 30% or more. In addition, "insoluble" refers to a state in which undissolved residue remains even after mixing, or a state in which phases appear cloudy at first glance but phase separates after an hour. "Cloudy" , means that the obtained mixed liquid 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 (hydrophilic-lipophilic balance) of the nonionic surfactant (B) is preferably 6 to 12, for example. If the HLB is within this range, the dispersibility of the hydrophobized inorganic powder (C) will be further enhanced, and even when this liquid dispersion is blended into O/W type cosmetics (oil-in-water type cosmetics), for example. The adsorption of the hydrophobized inorganic powder (C) to the skin is improved, and the water resistance is also improved.
In addition, when using two or more types of nonionic surfactants (B), it is preferable that the HLB of the mixture is within the above range. By doing so, when the dispersion of the present invention is blended in water, the surfactant does not dissolve in water but strongly adheres to the powder, making it possible to obtain good dispersibility. If the HLB is too high, a phenomenon of dissolution in water occurs, resulting in the appearance of hydrophobic parts of the powder, which may cause problems such as agglomeration after blending. Furthermore, if the HLB is too high, agglomeration is likely to occur when the polyalkylene glycol (A) is dispersed or, even if a dispersion is obtained, when blended with water.

In this specification, HLB is W. C. It is determined by the following equation defined by Griffin.
N _HLB = (E+P)/5
( _NHLB represents the HLB value. E represents the ratio (mass%) of the polyether moiety that the nonionic surfactant (B) has to the entire molecule of the nonionic surfactant (B). P represents the ratio (mass%) of the polyhydric alcohol moiety that the nonionic surfactant (B) has to the entire molecule of the nonionic surfactant (B).)

The content of the nonionic surfactant (B) is such that the mass ratio (A/B) of the polyalkylene glycol (A) having a total carbon number of 4 to 30 and the nonionic surfactant (B) is 70 to 70. It is preferable to set it to 95/30 to 5. This improves the dispersion of the hydrophobized inorganic powder (C). Furthermore, the liquid dispersion of the present invention can maintain good dispersion stability even when the amount of nonionic surfactant (B) is reduced. This makes it possible to improve the stability when using a liquid dispersion. From this point of view, the mass ratio (A/B) is more preferably from 72 to 95/28 to 5, even more preferably from 73 to 95/27 to 5.

-Hydrophobized inorganic powder (C)-
The hydrophobized inorganic powder (C) preferably has an average particle diameter of 150 to 700 nm. Normally, inorganic powders having a particle size that is considered to be pigment grade tend to settle, and therefore, according to conventional technical knowledge, it is considered that the dispersion stability is not good when made into a liquid dispersion. However, contrary to this common general knowledge, the liquid dispersion of the present invention has extremely good dispersion stability even when it contains the hydrophobized inorganic powder (C) having such a particle size. Particularly useful in applications such as From the viewpoint of achieving more beautiful color development, the wavelength is more preferably 180 nm or more, and even more preferably 200 nm or more.

In this specification, the average particle diameter of an inorganic powder is defined as the particle diameter of 200 particles randomly selected using a scanning electron micrograph (SEM photograph) and the average primary particle diameter calculated. means the value measured by the method. The diameter of the minimum circumscribed circle is used to calculate the diameter of each primary particle.

The shape of the hydrophobized inorganic powder (C) is not particularly limited, and includes, for example, spherical (including approximately spherical), rod-like, needle-like, spindle-like, plate-like, hexagonal plate-like, acicular aggregate, amorphous shape. etc.
The shape can be observed using a scanning electron microscope or the like.

The inorganic powder (also referred to as raw material inorganic powder) constituting the hydrophobized inorganic powder (C) is not particularly limited, and includes, for example, titanium oxide, iron oxide, zinc oxide, cerium oxide, barium sulfate, calcium carbonate, silica, Examples include aluminum hydroxide, alumina, boron nitride, talc, mica, and kaolin. Among these, titanium oxide, iron oxide, zinc oxide, cerium oxide, and composites thereof are preferred, which makes them more useful for cosmetic applications. More preferably, titanium oxide and/or iron oxide are used. Further, titanium oxide and iron oxide may be mixed and used in arbitrary amounts for the purpose of color toning and the like.

The raw material inorganic powder may also be a composite powder whose surface is coated with another inorganic material. In this case, by subjecting the composite powder to hydrophobization treatment, it will be used as hydrophobization-treated inorganic powder (C). Other inorganic materials are not particularly limited, and include, for example, zinc oxide, titanium oxide, cerium oxide, iron oxide, barium oxide, hydrous silicic acid, silica, aluminum hydroxide, alumina, zirconia, and the like. The amount of coating with these inorganic materials is preferably 0 to 25% by mass, for example, based on 100% by mass of the total amount of inorganic powder after hydrophobization treatment. More preferably, it is 2 to 20% by mass.

The hydrophobized inorganic powder (C) is obtained by hydrophobizing the raw material inorganic powder (which may be the composite powder described above). Hydrophobic treatment means treating the surface of the raw inorganic powder with a hydrophobic organic surface treatment agent. Hydrophobization treatment seals off the hydrophilic parts on the surface of the raw material inorganic powder to be treated, which improves water resistance and water repellency. Gel formation between the treated inorganic powder (C) and the water-soluble polymer is suppressed, and the squeaky feeling during use is also sufficiently reduced, making it more useful for cosmetic applications.

Here, the hydrophobized inorganic powder (C) (that is, the hydrophobized inorganic powder) preferably has a high degree of hydrophobization. Thereby, the stability of the liquid dispersion can be further increased. The degree of hydrophobization can be measured by the contact angle of water droplets when a hydrophobized inorganic powder is pressed into a flat plate with a uniform surface and 1 μL of water is dropped on the surface. The contact angle is preferably 45 degrees or more, more preferably 60 degrees or more, still more preferably 90 degrees or more.

The hydrophobic organic surface treatment agent is not particularly limited as long as it is an organic surface treatment agent commonly used for hydrophobizing the particle surface, but examples include silicone, alkylsilane, fatty acid (salt), amino acid (salt), and alkyl phosphorus. Preferably, it is at least one selected from the group consisting of acids (salts). Thereby, the effect of the above-mentioned hydrophobization treatment is further exhibited, and the release of the surface treatment agent from the inorganic powder is sufficiently suppressed, so that the dispersion stability is further improved.

The above salt is not particularly limited, and for example, metal salts, ammonium salts, and organic amine salts are preferred. Examples of metal atoms constituting the metal salt include monovalent metals such as sodium, lithium, potassium, rubidium, and cesium; divalent metals such as zinc, magnesium, calcium, strontium, and barium; trivalent metals such as aluminum; and iron. , other metals such as titanium, etc. Examples of the organic amine group constituting the organic amine salt include alkanolamine groups such as monoethanolamine group, diethanolamine group, and triethanolamine group; alkylamine groups such as monoethylamine group, diethylamine group, and triethylamine group; ethylenediamine group; Examples include polyamine groups such as triethylenediamine groups; and the like. Among the above salts, ammonium salts, sodium salts, and potassium salts are preferred, and sodium salts are more preferred.

Among the above hydrophobic organic surface treating agents, silicone is preferred. Examples of silicones include methylhydrogenpolysiloxane, dimethylpolysiloxane, copolymers of methylhydrogenpolysiloxane and dimethylpolysiloxane, and organopolysiloxanes containing reactive trialkoxysilyl groups such as trimethoxysilyl and triethoxysilyl groups. suitable.

In the hydrophobization treatment of inorganic powder, the hydrophobization treatment is performed at a rate of 0.1 to 10% by mass based on 100% by mass of the total amount of inorganic powder after treatment (hydrophobized inorganic powder (C)). It is preferable that the When the content is 0.1% by mass or more, water repellency and water resistance are further improved. Note that even if the amount exceeds 10% by mass, the effect of the hydrophobization treatment reaches a plateau. More preferably 0.2 to 9% by weight, still more preferably 0.5 to 8% by weight.

The content of the hydrophobized inorganic powder (C) is 40% by mass or more based on 100% by mass of the total amount of the liquid dispersion. By setting such a high concentration, when the liquid dispersion is used as a variety of raw materials, a necessary effect can be exerted even with a small amount of the liquid dispersion. The content of the hydrophobized inorganic powder (C) is preferably 50% by mass or more, more preferably 55% by mass or more, and still more preferably 60% by mass or more. Among them, when titanium oxide is used as an inorganic powder, the content is more preferably 60% by mass or more, particularly preferably 65% by mass or more, and most preferably 70% by mass or more. The upper limit is not particularly limited, but in consideration of the content of other components, it is preferably 95% by mass or less, more preferably 90% by mass or less.

In the liquid dispersion of the present invention, the total content of the essential components polyalkylene glycol (A) having a total carbon number of 4 to 30, the nonionic surfactant (B), and the hydrophobized inorganic powder (C) is preferably 80% by mass or more based on 100% by mass of the total amount of the liquid dispersion. The content is more preferably 85% by mass or more, still more preferably 90% by mass or more, particularly preferably 95% by mass or more, and most preferably 97% by mass or more. In addition, other components may be included as needed, and each component can be used alone or in combination of two or more.

-Other ingredients-
The liquid dispersion of the present invention preferably further contains lecithin and/or hydrogenated lecithin (D). By containing lecithin and/or hydrogenated lecithin (D), the adhesion of the hydrophobized inorganic powder (C) to the skin is improved, and makeup durability is improved. Note that lecithin and/or hydrogenated lecithin may be collectively referred to as "(hydrogenated) lecithin."

The content of lecithin and/or hydrogenated lecithin (D) (if two types are used, the total amount) is 0.01 to 10 parts by mass per 100 parts by mass of the total amount of hydrophobized inorganic powder (C). The proportions are favorable. If it is less than 0.01 parts by mass, no significant improvement in adhesion can be expected, and if it exceeds 10 parts by mass, problems such as stickiness may occur. More preferably 0.1 to 8 parts by weight, still more preferably 0.5 to 5 parts by weight, particularly preferably 0.5 to 3 parts by weight.

The liquid dispersion of the present invention may optionally contain the above-mentioned polyalkylene glycol having a total carbon number of 4 to 30 (A), a nonionic surfactant (B), a hydrophobized inorganic powder (C), In addition, other components other than lecithin and/or hydrogenated lecithin (D) may also be included. Other ingredients include, but are not particularly limited to, paraoxybenzoic acid alkyl ester, benzoic acid, sodium benzoate, sorbic acid, potassium sorbate, phenoxyethanol, salicylic acid, carbolic acid, sorbic acid, parachlormetacresol, hexachlorophene, chloride. Examples include antibacterial preservatives and antibacterial agents such as benzalkonium, chlorhexidine chloride, photosensitizers, and phenoxyethanol.

The content of other components is preferably 20% by mass or less, for example, based on 100% by mass of the total amount of the liquid dispersion. The content is more preferably 15% by mass or less, still more preferably 10% by mass or less, particularly preferably 5% by mass or less.

The manufacturing method for obtaining the liquid dispersion of the present invention is not particularly limited, and may be produced by mixing the above-mentioned components. The mixing method is not limited either, and any conventional method that can achieve uniform dispersion may be used. For example, a dispersing machine or device such as a bead mill, a jet mill, or a high-pressure homogenizer may be used, but the liquid dispersion of the present invention can be easily produced using a simple stirrer without using these expensive dispersing machines or devices. This also has the advantage of eliminating the need for an expensive dispersion machine such as a bead mill.

The liquid dispersion of the present invention preferably has a viscosity of 2,000 to 500,000 mPa·s at 25°C. When the viscosity is within this range, the hydrophobized inorganic powder (C) becomes more difficult to move (that is, less likely to settle), so that the dispersion stability is further improved. In particular, this effect becomes remarkable when the average particle diameter of the hydrophobized inorganic powder (C) is 150 nm or more, and viscosity increase over time is more fully suppressed, resulting in improved dispersion stability. The upper limit of the viscosity is more preferably 300,000 mPa·s or less, still more preferably 100,000 mPa·s or less, particularly preferably 50,000 mPa·s or less. The lower limit of the viscosity is more preferably 3000 mPa·s or more, still more preferably 5000 mPa·s or more, particularly preferably 7000 mPa·s or more, and most preferably 8000 mPa·s or more.

The "viscosity at 25°C" mentioned above refers to polyalkylene glycols having a total carbon number of 4 to 30 (A), nonionic surfactants (B), and hydrophobized inorganic powders (C). The viscosity is the viscosity of a liquid dispersion when no component is included. This liquid dispersion is prepared, left to stand at 40°C for one day, cooled to 25°C, and measured with a B-type viscometer (LVDV1M, manufactured by Hideko Seiki Co., Ltd.). (Measurement temperature: 25°C).

[Application]
The liquid dispersion of the present invention can maintain a stable dispersion state for a long period of time, so it is easy to store and transport as a dispersion, and it is easy to carry out dispersion treatment when dispersing the liquid dispersion in a dispersion medium. It can be simplified or omitted. Therefore, it is useful as a variety of raw materials, and is particularly useful as a raw material for cosmetics, a raw material for paints, and a raw material for ink. Among these, the liquid dispersion of the present invention is extremely useful as a raw material for cosmetics because it has good color development, good feel, and ease of handling, and can provide cosmetics that are resistant to sweat and water and have high water repellency. As described above, the cosmetic raw material comprising the liquid dispersion of the present invention is one of the aspects of the present invention. Furthermore, cosmetics, coating compositions, or ink compositions containing the liquid dispersion of the present invention are also included in the invention by the present inventor. Among these, cosmetics will be further explained below.

[Cosmetics]
The cosmetic of the present invention contains the liquid dispersion of the present invention described above. The method for producing such cosmetics is not particularly limited, and may be any method for producing ordinary cosmetics.

The above-mentioned cosmetics are not particularly limited, and include, for example, skin care products, hair products, makeup products, UV protection products, and the like. The shape of the cosmetic is not particularly limited, and examples include liquid, emulsion, cream, solid, paste, gel, multilayer, mousse, and spray.

The above cosmetic may also be any of oil-based cosmetics, water-based cosmetics, O/W type cosmetics (oil-in-water type cosmetics), and W/O type cosmetics (water-in-oil type cosmetics). That is, the liquid dispersion of the present invention can be suitably applied to any of these. Among these, it can be particularly preferably applied to both O/W type cosmetics and W/O type cosmetics. As an O/W type cosmetic, a cosmetic that is used in combination with an anionic water-soluble polymer is preferable, but in this case, by using the liquid dispersion of the present invention, a cosmetic that is used in combination with an anionic water-soluble polymer In W/O type cosmetics, water evaporation improves the adhesion of pigments to the skin after the cosmetics are applied to the skin. , and the longevity of makeup can be improved.

The above-mentioned cosmetic may contain one or more arbitrary aqueous components and oil-based components that are commonly used in the cosmetics field, as necessary. Aqueous components and oil-based components are not particularly limited, but include, for example, oils, surfactants, humectants, higher alcohols, sequestering agents, natural or synthetic polymers, water-soluble or oil-soluble polymers, ultraviolet shielding agents, and various Extracts, pharmaceutical ingredients, colorants (dyes, pigments, etc.), preservatives, antioxidants, pigments, thickeners, pH adjusters, fragrances, cooling agents, antiperspirants, bactericides, skin activators, various Examples include powder.

Examples are given below to explain the present invention in detail, but the present invention is not limited only to these examples. Unless otherwise specified, "%" means "% by mass (% by weight)" and "parts" means "parts by mass (parts by weight)".

Various physical properties in Examples were measured as follows.
1. Viscosity was measured using a B-type viscometer (LVDV1M, manufactured by Hideko Seiki Co., Ltd.) (measurement temperature: 25°C).
2. After diluting the liquid dispersion containing white inorganic powder with particle size distribution with water, the median diameter D ₅₀ on a volume basis was measured using "LA-950" manufactured by Horiba, Ltd.

Example 1
22 g of polyethylene glycol with an average molecular weight of 200 (“PEG #200” manufactured by NOF Corporation, average repeating number of ethylene glycol 4), nonionic surfactant (“KF-6013” manufactured by Shin-Etsu Chemical Co., Ltd., polyether-modified silicone) 3 g and 75 g of silicone-treated titanium oxide (“MKR-1S” manufactured by Sakai Chemical Industries, average particle size: 200 nm) were mixed in a 100 ml ointment bottle and mixed with a medicine spoon. Thereafter, the mixture was kneaded for 10 minutes at 1500 rpm using a mixer ("Awatori Rentaro" manufactured by Thinky), and then mixed for 1 minute at 2100 rpm for defoaming.
Regarding the obtained liquid dispersion 1, the particle size was measured, the viscosity and odor changed over time, and the state of the supernatant after storage for one month was confirmed. Odor was confirmed by smelling the liquid dispersion, and the state of the supernatant was visually confirmed. The results are shown in Table 1.

Example 2
Liquid dispersion was carried out in the same manner as in Example 1, except that polyethylene glycol with an average molecular weight of 400 (“PEG #400” manufactured by NOF Corporation, average repeating number of ethylene glycol was 8) was used instead of polyethylene glycol with an average molecular weight of 200. Body 2 was prepared. The obtained liquid dispersion 2 was subjected to various evaluations in the same manner as in Example 1. The results are shown in Table 1.

Examples 3 and 4
Example except that the amount of nonionic surfactant (“KF-6013” manufactured by Shin-Etsu Chemical Co., Ltd., polyether-modified silicone) was changed to 1.5 g (Example 3) and 6 g (Example 4). Liquid dispersions 3 and 4 were prepared in the same manner as in Example 2. The obtained liquid dispersions 3 and 4 were subjected to various evaluations in the same manner as in Example 1. The results are shown in Table 1.

Example 5
Instead of 22 g of polyethylene glycol with an average molecular weight of 200, 22.5 g of polypropylene glycol ("Uniol D250" manufactured by NOF Corporation, average repeating number of propylene glycol 4) was used, and 22.5 g of polypropylene glycol (manufactured by Shin-Etsu Chemical Co., Ltd. " Liquid dispersion 5 was prepared in the same manner as in Example 1, except that the amount of "KF-6013" (polyether modified silicone) used was changed to 2.5 g. The obtained liquid dispersion 5 was subjected to various evaluations in the same manner as in Example 1. The results are shown in Table 1.

Comparative example 1
Comparative liquid dispersion 1 was prepared in the same manner as in Example 1 except that 1,3-butylene glycol (manufactured by Daicel Corporation) was used instead of polyethylene glycol having an average molecular weight of 200. Regarding the obtained comparative liquid dispersion 1, various evaluations were performed in the same manner as in Example 1. The results are shown in Table 1.

Comparative example 2
Except that 18 g of glycerin was used instead of 22 g of polyethylene glycol with an average molecular weight of 200, and the amount of nonionic surfactant ("KF-6013" manufactured by Shin-Etsu Chemical Co., Ltd., polyether-modified silicone) was changed to 7 g. Comparative liquid dispersion 2 was prepared in the same manner as in Example 1. Regarding the obtained comparative liquid dispersion 2, various evaluations were performed in the same manner as in Example 1. The results are shown in Table 1.

Comparative example 3
Instead of 22 g of polyethylene glycol with an average molecular weight of 200, 47 g of polyethylene glycol with an average molecular weight of 1000 ("PEG #1000" manufactured by NOF Corporation, average repeating number of ethylene glycol 20) was used, and silicone-treated titanium oxide (manufactured by Sakai Chemical Industry Co., Ltd.) was used. Comparative liquid dispersion 3 was prepared in the same manner as in Example 1, except that the amount of "MKR-1S" (average particle size: 200 nm) used was changed to 50 g. Regarding the obtained comparative liquid dispersion 3, various evaluations were performed in the same manner as in Example 1. The results are shown in Table 1. Note that because Comparative Liquid Dispersion 3 gelled after one month, the viscosity, supernatant, and odor after one month were not evaluated.

As shown in Table 1, in Examples 1 to 5 using polyalkylene glycols with a total carbon number in the range of 4 to 30, the dispersibility was good and the supernatant remained even after one month. In contrast, in Comparative Examples 1 and 2 using 1,3-butylene glycol and glycerin, liquid dispersions with good dispersibility were obtained, but the formation of supernatant was observed after one month. It was done. Further, in Comparative Example 3 using polyalkylene glycol having a total carbon number of 40, gelation occurred after one month. Furthermore, in Examples 1 to 5, no odor was generated even after one month.
From these results, by using polyalkylene glycol with a total carbon number of 4 to 30 as the polyhydric alcohol, a liquid dispersion with particularly excellent dispersion stability that does not cause liquid floating or supernatant formation even when stored for a long period of time can be created. It has been confirmed that it can be obtained.

Claims (8)

A liquid dispersion comprising a polyalkylene glycol (A) having a total carbon number of 4 to 30, a nonionic surfactant (B) and a hydrophobized inorganic powder (C),
The polyalkylene glycol (A) having a total carbon number of 4 to 30 is at least one selected from polyethylene glycol and polypropylene glycol,
The mass ratio (A/B) of the polyalkylene glycol (A) having a total carbon number of 4 to 30 and the nonionic surfactant (B) is 70 to 95/30 to 5,
A liquid dispersion comprising 40% by weight or more of the hydrophobized inorganic powder (C) based on 100% by weight of the total amount of the liquid dispersion. The liquid dispersion according to claim 1, wherein the polyalkylene glycol is hydrophilic. The liquid dispersion according to claim 1 or 2, wherein the hydrophobized inorganic powder (C) has an average particle diameter of 150 to 700 nm. The hydrophobized inorganic powder (C) is an inorganic powder surface-treated with at least one member selected from the group consisting of silicone, alkylsilane, fatty acid (salt), amino acid (salt), and alkylphosphoric acid (salt). The liquid dispersion according to any one of claims 1 to 3 , which is a liquid dispersion. The liquid dispersion according to any one of claims 1 to 4 , wherein the nonionic surfactant (B) is a polyether-modified silicone. The liquid dispersion according to any one of claims 1 to 5, having a viscosity of 2,000 to 500,000 mPa·s at 25°C. A cosmetic raw material comprising the liquid dispersion according to any one of claims 1 to 6 . A cosmetic comprising the liquid dispersion according to any one of claims 1 to 6 .