WO2021100676A1

WO2021100676A1 - External preparation for skin

Info

Publication number: WO2021100676A1
Application number: PCT/JP2020/042695
Authority: WO
Inventors: 典子手島; 真由美武谷
Original assignee: 花王株式会社
Priority date: 2019-11-20
Filing date: 2020-11-17
Publication date: 2021-05-27
Also published as: JP2021080251A; CN114727920A; KR20220080162A; TW202128123A

Abstract

This external preparation for skin is obtained by combining the following components (a) through (c): (a) a plate-like metal oxide having a thickness of 100 to 120 nm, (b) a plate- like metal oxide having a thickness of 125 to 145 nm, and (c) a plate-like metal oxide having a thickness of 180 to 200 nm. In terms of a total of 100 mass% of the amounts added of components (a) through (c) , the content of component (a) is 5 to 70 mass%, the content of component (b) is 15 to 75 mass%, and the content of component (c) is 5 to 70 mass%.

Description

Topical skin agent

The present invention relates to an external preparation for skin.

From the viewpoint of skin protection against sunlight, UV protection cosmetics such as sunscreen cosmetics are known. On the other hand, in recent years, due to heightened health consciousness, there is a demand for external preparations for skin having a protective function against infrared rays.
Regarding external preparations for skin having an infrared protective function, for example, Patent Document 1 (International Publication No. 2009/017104) states that infrared rays prevent infrared rays from reaching deeper into the dermis and subcutaneous tissues than the tissues of the skin, and those by infrared rays. As a technique relating to an inhibitor for preventing tissue damage, an inhibitor for near-infrared damage to living tissue containing an infrared transmission shielding agent composed of titanium oxide powder and zinc oxide powder has been disclosed. Further, Patent Document 2 (Japanese Unexamined Patent Publication No. 2017-95361) discloses a near-infrared protective cosmetic composition composed of titanium oxide powder and zinc oxide powder, which has both excellent near-infrared protection effect and high transparency. Has been done.

The present invention relates to the following [1] and [2].
[1] The following components (a) to (c):
(A) Plate-like metal oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped metal oxides with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped metal oxides with a thickness of 180 nm or more and 200 nm or less.
The compounding amount of the component (a) is 5% by mass or more and 70% by mass or less, and the compounding amount of the component (b) is 100% by mass with respect to the total compounding amount of the components (a) to (c) of 100% by mass. An external preparation for skin having an amount of 15% by mass or more and 75% by mass or less and a blending amount of the component (c) of 5% by mass or more and 70% by mass or less.
[2] A method for protecting the skin from infrared rays by applying the external preparation for skin according to the above [1] to the skin.

It is a three-phase diagram which showed mass% of component (a), component (b) and component (c) in 100 mass% of the total compounding amount of component (a)-(c) in the external preparation for skin.

Detailed description of the invention

[Skin external preparation]
The external preparation for skin of the present invention contains the following components (a) to (c):
(A) Plate-like metal oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped metal oxides with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped metal oxides with a thickness of 180 nm or more and 200 nm or less.
The compounding amount of the component (a) is 5% by mass or more and 70% by mass or less, and the compounding amount of the component (b) is 100% by mass with respect to the total compounding amount of the components (a) to (c) of 100% by mass. It is 15% by mass or more and 75% by mass or less, and the blending amount of the component (c) is 5% by mass or more and 70% by mass or less.
Since the external preparation for skin of the present invention has the above structure, it has an excellent infrared ray protection effect and can obtain a natural color that blends with the skin color when applied to the skin.

For skin protection, an external preparation for skin with further improved infrared protection function is desired rather than the disclosed techniques of

Patent Documents

1 and 2. Further, among the external preparations for skin, as a skin cosmetic, if it exhibits redness or bluish color, it becomes an unnatural color when applied to the skin, so that it is also required to have a color that matches the color of the skin.
The present invention relates to an external preparation for skin that has an excellent infrared protection effect, is less likely to have redness or bluish color when applied to the skin, and can obtain a natural color that blends in with the skin color.

The present inventors have found that a skin external preparation containing a combination of plate-like metal oxides having a predetermined thickness range and different thicknesses in a predetermined ratio can solve the above-mentioned problems.

The external preparation for skin of the present invention has an excellent infrared protective effect, and when applied to the skin, redness and blueness are less likely to be recognized, and a natural color that blends in with the skin color can be obtained. For example, skin makeup. It is useful as a fee.

In the present invention, the thickness of the plate-shaped metal oxide means the length of the shortest shaft of the plate-shaped metal oxide particles.
In the present invention, infrared rays mean electromagnetic waves having a wavelength of 780 nm to 1 mm. Of these, the external preparation for skin of the present invention is particularly excellent in the near-infrared ray protection effect having a wavelength of 780 nm to 2500 nm. As a result, it is possible to suppress an increase in skin temperature due to sunlight irradiation and obtain a high feeling of heat insulation.
In this specification, the infrared protection rate with a wavelength of 1500 nm is used as an index as the infrared protection effect.

The dosage form of the external preparation for skin of the present invention is not particularly limited, but it is preferably liquid, gel-like, or cream-like from the viewpoint of ease of application to the skin. The external preparation for skin may be in the form of an emulsified composition, and the emulsified composition may be either an oil-in-water emulsified composition or a water-in-oil emulsified composition.
Further, the external skin preparation of the present invention is preferably a skin cosmetic such as a sunscreen cosmetic (skin water, cream, milky lotion, beauty essence, etc.), suntan, makeup base cosmetic, and the like.

<Components (a) to (c): Plate-like metal oxide>
The external preparation for skin of the present invention contains the following components (a) to (c):
(A) Plate-like metal oxide with a thickness of 100 nm or more and 120 nm or less,
(B) A plate-shaped metal oxide having a thickness of 125 nm or more and 145 nm or less, and (c) a plate-shaped metal oxide having a thickness of 180 nm or more and 200 nm or less are blended.
By blending the above-mentioned predetermined plate-shaped metal oxides as the components (a) to (c) in a predetermined ratio, the external preparation for skin of the present invention has an excellent infrared protection effect, a high heat-shielding feeling can be obtained, and the skin becomes white. It is difficult to use, and when applied to the skin, it also has the effect of obtaining a natural color that blends in with the skin color. The reason for this is not clear, but it can be considered as follows.

It is known that, among skin external preparations containing inorganic particles such as titanium oxide, the one having a large particle size has a higher infrared protection effect. However, there is a limit to the improvement of the infrared protection effect simply by using inorganic particles having a large particle size. Further, for example, when spherical inorganic particles having a particle size larger than the wavelength of visible light are blended in an external preparation for skin, when applied to the skin, the particles become white due to light scattering of visible light on the surface of the particles. It had the drawback of being easy.
On the other hand, the present inventors selectively increase the reflectance of light in the infrared region by the interference effect of light by using a plate-shaped metal oxide having a predetermined thickness as an infrared protective agent in an external preparation for skin. However, it has been found that the reflectance of light in the visible region can be reduced, which makes it possible to achieve both an infrared protection effect and an effect of preventing whitening when applied to the skin.
On the other hand, an external preparation for skin containing a plate-like metal oxide as an infrared protective agent may have an unnatural color that does not blend with the skin, such as redness and blueness being observed when applied to the skin. It was found that there is. In response to such a problem, the present inventors have achieved a high infrared protection effect by blending the components (a) to (c), which are plate-shaped metal oxides having different thicknesses, in the predetermined ratios. We have found that it is compatible with the natural color when applied to the skin. Regarding the hue, the components (a) to (c) exhibit red, blue, and green interference colors, respectively, due to the wavelength of the reflected light. However, by setting the blending amount of each component within a predetermined range, the skin It is probable that a natural shade that blends in with the skin color could be obtained when applied to.

The thickness of the components (a) to (c) from the viewpoint of obtaining an excellent infrared protection effect by the above-mentioned action mechanism, and from the viewpoint of obtaining a natural color without becoming white when the external preparation for skin is applied to the skin. Is preferably in the following range, respectively.
The thickness of the component (a) is 100 nm or more, preferably 105 nm or more, 120 nm or less, preferably 115 nm or less. The component (a) having a thickness in the above range exhibits a reddish interference color due to the wavelength of the reflected light.
The thickness of the component (b) is 125 nm or more, preferably 130 nm or more, and 145 nm or less, preferably 140 nm or less. The component (b) having a thickness in the above range exhibits a bluish interference color due to the wavelength of the reflected light.
The thickness of the component (c) is 180 nm or more, preferably 185 nm or more, and 200 nm or less, preferably 195 nm or less. The component (c) having a thickness in the above range exhibits a greenish interference color due to the wavelength of the reflected light.
The thicknesses of the components (a) to (c) can all be determined from the observation image by the scanning electron microscope (SEM). Specifically, the plate-shaped metal oxides of the components (a) to (c) are observed by SEM under the condition of an observation magnification of 10,000 times, and the thickness of 50 particles in the observation image is measured. Therefore, it is obtained by calculating the average value of the thickness per number. Specifically, the thicknesses of the components (a) to (c) can be measured by the method described in Examples.

From the viewpoint of reducing glare when the external preparation for skin is applied to the skin, the average particle size of the components (a) to (c) is preferably 20 μm or less, more preferably 15 μm or less, still more preferably 12 μm or less, and further. It is preferably 10 μm or less. On the other hand, the average particle size of the components (a) to (c) is determined from the viewpoint of obtaining an excellent infrared protection effect and from the viewpoint of obtaining a natural color tone without becoming white when an external preparation for skin is applied to the skin. It is preferably 1 μm or more, more preferably 2 μm or more, still more preferably 3 μm or more, still more preferably 5 μm or more. The specific range of the average particle size of the components (a) to (c) is preferably 1 μm or more and 20 μm or less, more preferably 2 μm or more and 15 μm or less, still more preferably 2 μm or more and 12 μm or less, still more preferably 3 μm or more and 10 μm or less. Even more preferably, it is 5 μm or more and 10 μm or less.
The average particle size of the components (a) to (c) is a median diameter (D50) measured at a particle size reference volume using a laser diffraction / scattering type particle size distribution measuring device. It can be measured by the method described.

Further, from the viewpoint of obtaining an excellent infrared protection effect and obtaining a natural color when the external preparation for skin is applied to the skin, the aspect ratios of the components (a) to (c) are preferably 10 or more. It is preferably 20 or more, more preferably 30 or more, and even more preferably 35 or more. Further, from the viewpoint of obtaining an excellent infrared protection effect and from the viewpoint of preventing whitening and reducing glare when the external preparation for skin is applied to the skin, it is preferably 200 or less, more preferably 150 or less, still more preferably. It is 100 or less, more preferably 90 or less. The specific range of the aspect ratios of the components (a) to (c) is preferably 10 or more and 200 or less, more preferably 10 or more and 150 or less, still more preferably 10 or more and 100 or less, still more preferably 20 or more and 100 or less, and more. It is more preferably 30 or more and 100 or less, and even more preferably 35 or more and 90 or less.
The aspect ratios of the components (a) to (c) can be calculated from (average particle size / thickness).

The degree of glare when the external preparation for skin is applied to the skin is evaluated by measuring the gloss value at an angle of 60 ° using a gloss value measuring device for the coating film obtained by applying the external preparation for skin. Can be done.

As the metal oxides constituting the components (a) to (c), a material having a high refractive index can obtain a higher optical interference effect. From this point of view, preferable metal oxides constituting the components (a) to (c) include titanium oxide, zinc oxide, zirconium oxide, iron oxide, aluminum oxide, cerium oxide and the like. Among these, one or more selected from the group consisting of titanium oxide and zinc oxide is preferable, and titanium oxide is more preferable. That is, the components (a) to (c) are preferably one or more selected from the group consisting of plate-shaped titanium oxide and plate-shaped zinc oxide, and more preferably plate-shaped titanium oxide.
The crystal structure of titanium oxide may be rutile type, anatase type, or amorphous, but the rutile type is preferable from the viewpoint of obtaining an excellent infrared protection effect and a feeling of heat shielding.

The plate-shaped metal oxides of the components (a) to (c) may not be surface-treated, and may be treated with a hydrophobic treatment by a known method, if necessary, in order to enhance the dispersibility in the external preparation for skin. It may be the one which has been subjected to the surface treatment of. The plate-shaped metal oxides of the components (a) to (c) are distinguished from those in which the surface of particles other than the metal oxide is surface-treated with the metal oxide.

Examples of the surface treatment agent used for the surface treatment of the plate-shaped metal oxides according to the components (a) to (c) include silicone; alkylalkoxysilane; fluorine-containing compounds such as perfluoroalkyl phosphate and perfluoroalcohol; N. -Amino acids such as acylglutamic acid; other examples include lecithin; metal soap; fatty acids such as stearic acid; alkyl phosphates and the like. Among these, one or more selected from the group consisting of silicone and alkylalkoxysilane is preferable from the viewpoint of enhancing the dispersibility of the components (a) to (c) in the external preparation.
Silicone as a surface treatment agent is not particularly limited, and for example, methylpolysiloxane, dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, methylcyclopolysiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, etc. Dodecamethylcyclohexasiloxane, octamethyltrisiloxane, tetradecamethylhexasiloxane, dimethylsiloxane / methyl (polyoxyethylene) siloxane / methyl (polyoxypropylene) siloxane copolymer, dimethylsiloxane / methyl (polyoxyethylene) siloxane Various types such as polymers, dimethylsiloxane / methyl (polyoxypropylene) siloxane copolymers, dimethylsiloxane / methylcetyloxysiloxane copolymers, dimethylsiloxane / methylstealoxysiloxane copolymers, (alkyl acrylate / dimethicone) copolymers, etc. Siloxane oil can be mentioned.
As the alkylalkoxysilane as the surface treatment agent, those having a branched or linear alkyl group having 6 to 20 carbon atoms are preferable, and examples thereof include octyltriethoxysilane and octyltrimethoxysilane.
From the viewpoint of improving the infrared protection effect, the surface treatment agent is selected from the group consisting of methylpolysiloxane, dimethylpolysiloxane, methylhydrogenpolysiloxane, (alkyl acrylate / dimethicone) copolymer, and octylriethoxysilane1. More than a seed is preferred.

In the external preparation for skin of the present invention, the blending amount of the component (a) is 5% by mass or more and 70% by mass or less with respect to 100% by mass of the total blending amount of the components (a) to (c), and the blending amount of the component (b). Is 15% by mass or more and 75% by mass or less, and the blending amount of the component (c) is 5% by mass or more and 70% by mass or less. When the blending amount of each component with respect to the total blending amount of the components (a) to (c) is within the above range, an excellent infrared ray protection effect and a natural color when the external preparation for skin is applied to the skin can be obtained. It is compatible. Above all, regarding the infrared protection effect, when the blending amount of the component (a) is 70% by mass or less with respect to the total blending amount of the components (a) to (c) of 100% by mass, an excellent infrared protection effect can be obtained. Found.

The skin external preparation of the present invention has a total blending amount of 100% by mass of the components (a) to (c) from the viewpoint of achieving both an excellent infrared protection effect and a natural color when the skin external preparation is applied to the skin. It is preferable that the blending ratio of the component (a), the component (b) and the component (c) with respect to the above condition 1 satisfies the following condition 1, and more preferably the following condition 2 is satisfied.
Condition 1: In a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total blending amount of the components (a) to (c), the blending ratio of each component is , It is within the range of the composition region surrounded by the 6 composition points shown below.
(A, b, c) = (70,15,15), (28,26,46), (5,40,55), (5,67,28), (20,68,12), (57 , 33, 10)
Condition 2: In a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total blending amount of the components (a) to (c), the blending ratio of each component is , It is within the range of the composition region surrounded by the 6 composition points shown below.
(A, b, c) = (50,28,22), (25,45,30), (25,32,43), (15,43,42), (23,55,22), (42) , 43, 15)

The

above conditions

1 and 2 will be described with reference to the drawings.
FIG. 1 is a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) in the total blending amount of the components (a) to (c) in the external preparation for skin of 100% by mass. .. In the three-phase diagram of FIG. 1, in the region 1 surrounded by the thick solid line, the blending amount of the component (a) is 5% by mass or more and 70% by mass or less with respect to the total blending amount of 100% by mass of the components (a) to (c). , The composition region in which the blending amount of the component (b) is 15% by mass or more and 75% by mass or less and the blending amount of the component (c) is 5% by mass or more and 70% by mass or less is shown.
The region 2 surrounded by the broken line in the three-phase diagram of FIG. 1 is a composition region satisfying the above condition 1. In FIG. 1, (a, b, c) = (70,15,15), (28,26,46), (5,40,55), (5,67,28), (20,68,12). ) And (57, 33, 10) are indicated by "○".
The region 3 surrounded by the alternate long and short dash line in the three-phase diagram of FIG. 1 is a composition region that satisfies the above condition 2. In FIG. 1, (a, b, c) = (50,28,22), (25,45,30), (25,32,43), (15,43,42), (23,55,22). ) And (42, 43, 15) are indicated by “Δ”.

The total amount of the components (a) to (c) in the external preparation for skin of the present invention is preferably 1% by mass or more, more preferably 1.5% by mass or more, still more preferably, from the viewpoint of obtaining an excellent infrared protection effect. Is 2% by mass or more. Further, from the viewpoint of obtaining a natural color that does not easily turn white when the external preparation for skin is applied to the skin and from the viewpoint of economy, it is preferably 35% by mass or less, more preferably 25% by mass or less, still more preferably 20. It is mass% or less, more preferably 15 mass% or less, still more preferably 10 mass% or less. The specific range of the total blending amount of the components (a) to (c) in the external preparation for skin of the present invention is preferably 1% by mass or more and 35% by mass or less, more preferably 1% by mass or more and 25% by mass or less, still more preferably. Is 1% by mass or more and 20% by mass or less, more preferably 1% by mass or more and 15% by mass or less, further preferably 1.5% by mass or more and 10% by mass or less, still more preferably 2% by mass or more and 10% by mass or less. Is.

The external preparation for skin of the present invention does not exclude the addition of plate-shaped metal oxides other than the components (a) to (c), but the amount thereof is small from the viewpoint of obtaining the effects of the present invention. Is preferable. Specifically, the ratio of the components (a) to (c) in the total amount of the plate-shaped metal oxide blended in the external preparation for skin is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably. Is 90% by mass or more, more preferably 95% by mass or more, and 100% by mass or less.

Commercially available plate-shaped metal oxides can also be used as the components (a) to (c). For example, as commercially available plate-shaped titanium oxide, CQV's "Featheleve PT-9001K", "Featheleve PT-7001K", "Featheleve PT-7401K", "Featheleve PT-7801K", "Featheleve PT-7901K" and the like can be mentioned. .. It is more preferable to use these plate-shaped titanium oxides that have undergone the surface treatment as the components (a) to (c).
Further, in order to adjust the aspect ratio or the average particle size of the plate-shaped metal oxide within the above range, commercially available plate-shaped metal oxide or a surface-treated product thereof is pulverized by a pulverizer, and the components (a) to ( It may be used as c). The pulverization treatment method is not particularly limited, and a known method can be used. When the surface-treated plate-shaped metal oxide is used, the pulverization treatment may be performed at any stage before the surface treatment and after the surface treatment.

<Ingredient (d): Tactile improver>
The external preparation for skin of the present invention further contains a feel-improving agent as a component (d) from the viewpoint of suppressing stickiness when applied to the skin and obtaining a smooth and good feel when an oil agent or the like described later is blended. It is preferable to do so.
The feel improving agent may be any of organic particles, inorganic particles other than the above-mentioned components (a) to (c), and a mixture thereof, and those usually blended in cosmetics can be used. From the viewpoint of obtaining a good feel when applied to the skin, the shape of the particles is preferably spherical. Further, those having irregularities on the particle surface or those having a porous surface may be used.

Examples of the organic particles used as the component (d) include acrylic resin, silicone resin, polystyrene resin, polyamide resin, polyester resin, polyolefin resin, polystyrene resin, polyurethane resin, vinyl resin, urea resin, phenol resin, and fluororesin. Examples thereof include resin particles composed of resins such as melamine resin, epoxy resin, polycarbonate resin, acrylic-silicone copolymer resin, acrylic-styrene copolymer resin, and cellulose. These resin particles may be crosslinked resin particles or non-crosslinked resin particles.
Metal oxide particles are preferable as the inorganic particles other than the components (a) to (c), and examples of the metal oxide include titanium oxide, zinc oxide, zirconium oxide, iron oxide, aluminum oxide, and cerium oxide. Be done. Among these, one or more selected from the group consisting of titanium oxide and zinc oxide is preferable, and titanium oxide is more preferable.

Among the above, the component (d) is preferably a spherical inorganic particle, more preferably a spherical metal oxide particle, and further preferably one selected from the group consisting of spherical titanium oxide particles and spherical zinc oxide particles. These are the above, and even more preferably, spherical titanium oxide particles.

The average particle size of the particles used as the component (d) is preferably 0.1 μm or more, more preferably 0.2 μm or more, still more preferably 0.2 μm or more, from the viewpoint of suppressing stickiness when applied to the skin and obtaining a good feel. Is 0.5 μm or more. Further, from the viewpoint of suppressing stickiness when applied to the skin to obtain a good feel, and from the viewpoint of preventing whitening when the external preparation for skin is applied to the skin, it is preferably 10 μm or less, more preferably 5 μm or less, and further. It is preferably 2 μm or less. The specific range of the average particle size of the particles used as the component (d) is preferably 0.1 μm or more and 10 μm or less, more preferably 0.2 μm or more and 5 μm or less, and further preferably 0.5 μm or more and 2 μm or less. The average particle size can be measured by the same method as described above.

When the component (d) is used in the external preparation for skin of the present invention, its content is preferably 1% by mass or more in the external preparation for skin from the viewpoint of suppressing stickiness when applied to the skin and obtaining a good feel. , More preferably 1.5% by mass or more, still more preferably 2% by mass or more. Further, from the viewpoint of suppressing stickiness when applied to the skin to obtain a good feel, and from the viewpoint of preventing whitening when the external preparation for skin is applied to the skin, it is preferably 20% by mass or less, more preferably 15% by mass. % Or less, more preferably 10% by mass or less. The specific range of the content of the component (d) in the external preparation for skin of the present invention is preferably 1% by mass or more and 20% by mass or less, more preferably 1% by mass or more and 15% by mass or less, and further preferably 1% by mass or more. It is 10% by mass or less, more preferably 1.5% by mass or more and 10% by mass or less, and even more preferably 2% by mass or more and 10% by mass or less.

In the external preparation for skin of the present invention, the mass ratio [{(a) + (b) + (c)} / (d)] of the total amount of the components (a) to (c) and the component (d) is determined. From the viewpoint of obtaining an excellent infrared protection effect and from the viewpoint of obtaining a natural color tone that does not easily turn white when an external preparation for skin is applied to the skin, it is preferably 0.1 or more, more preferably 0.2 or more, and further. It is preferably 0.5 or more. Further, from the viewpoint of suppressing stickiness when applied to the skin and obtaining a good feel, it is preferably 5 or less, more preferably 3 or less, still more preferably 2 or less, still more preferably 1.5 or less. The specific range of the mass ratio [{(a) + (b) + (c)} / (d)] is preferably 0.1 or more and 5 or less, more preferably 0.2 or more and 3 or less, and further preferably 0. It is .5 or more and 2 or less, more preferably 0.5 or more and 1.5 or less.

<Component (e): UV absorber>
The external preparation for skin of the present invention preferably further contains an ultraviolet absorber as a component (e) from the viewpoint of imparting an ultraviolet protection effect in addition to the infrared protection effect.
As the component (e), an organic ultraviolet absorber is preferable, and an oil-soluble organic ultraviolet absorber or a water-soluble organic ultraviolet absorber can be used. The component (e) is preferably an oil-soluble organic UV absorber from the viewpoints of UV protection effect, natural appearance when applied to the skin, good cosmetic adhesion after application, and suppression of stickiness. .. The term "oil-soluble" means that it is water-insoluble, and specifically means that the solubility in water is 1 w / w% or less.
From the viewpoint of obtaining the effect of the present invention, the component (e) is distinguished from an inorganic ultraviolet absorber such as an ultraviolet absorber in which the surface of an inorganic filler is coated with an ultraviolet absorbing material.

As the oil-soluble organic UV absorber, an oil-soluble one among salicylic acid-based UV absorbers, cinnamic acid-based UV absorbers, benzoylmethane-based UV absorbers, and other organic UV absorbers can be used.
For example, salicylic acid-based UV absorbers such as homomentyl salicylate and octyl salicylate;
2-Ethylhexyl paramethoxycinnamate (for example, "Ubinal MC80" manufactured by BASF), glyceryl diparamethoxycinnamate mono-2-ethylhexanate, methyl 2,5-diisopropylsilicate, methylbis trimethoxycinnamate (Trimethylsiloxy) Cinnamic acid-based ultraviolet absorbers such as silylisopentyl and isopropyl-diisopropylsilicate ester mixture of paramethoxycinnamate;
Benzoylmethane-based UV absorbers such as 4-isopropyldibenzoylmethane and 4-tert-butyl-4'-methoxydibenzoylmethane (for example, "Parasol 1789" manufactured by DSM Nutrition Japan);
Octocrylene (for example, "Parasol 340" manufactured by DSM Nutrition Japan), 2-ethylhexyl dimethoxybenzylidene dioxoimidazolidine propionate (for example, "Soft Shade DH" manufactured by Ajinomoto Co., Ltd.), 1- (3,4-dimethoxyphenyl) ) -4,4-Dimethyl-1,3-pentandione, synoxate, methyl-O-aminobenzoate, 3- (4-methylbenzylidene) phenyl, octylriazone, hexyl diethylaminohydroxybenzoyl benzoate (2- (4- (4-4-methylbenzylidene)) Diethylamino-2-hydroxybenzoyl) benzoic acid hexyl ester, eg, BASF "Ubinal Aplus"), bisethylhexyloxyphenol methoxyphenyltriazine (2,4-bis {[4- (2-ethylhexyloxy) -2-hydroxy) ] Phenyl} -6- (4-methoxyphenyl) -1,3,5-triazine, eg, BASF "Tinosorb S"), methylenebisbenzotriazolyltetramethylbutylphenol (eg, BASF "Tinosorb M") , 2,4,6-Tris [4- (2-ethylhexyloxycarbonyl) anilino] -1,3,5-triazine (hereinafter, also referred to as "ethylhexyltriazone". For example, "Ubinal T150" manufactured by BASF). ; Etc. can be mentioned.

As a water-soluble organic UV absorber, salicylic acid-based UV absorber, silicic acid-based UV absorber, benzoylmethane-based UV absorber, and other organic UV absorbers have a solubility in water of 1 w / w%. Those exceeding the above can be used, and examples thereof include salicylic acid triethanolamine salt, p-methoxyhydrosilicate diethanolamine salt and the like.

Among the above, from the viewpoint of ultraviolet protection effect, the component (e) includes 2-ethylhexyl paramethoxysilicate, 4-tert-butyl-4'-methoxydibenzoylmethane, octocrylene, and dimethoxybenzylidene dioxoimidazolidine propionic acid. 2-Ethylhexyl, diethylaminohydroxybenzoyl hexyl benzoate, bisethylhexyloxyphenol methoxyphenyltriazine, methylenebisbenzotriazolyltetramethylbutylphenol, and 2,4,6-tris [4- (2-ethylhexyloxycarbonyl) anilino ] -1,3,5-Triazine is preferably one or more selected from the group consisting of 2-ethylhexyl paramethoxysilicate, hexyl diethylaminohydroxybenzoylbenzoate, bisethylhexyloxyphenol methoxyphenyltriazine, and 2,4. More preferably, one or more selected from the group consisting of 6-tris [4- (2-ethylhexyloxycarbonyl) anilino] -1,3,5-triazine. More preferably, it is one or more selected from the group consisting of 2-ethylhexyl paramethoxycinnamate, hexyl diethylaminohydroxybenzoylbenzoate, and bisethylhexyloxyphenol methoxyphenyl triazine.

When the component (e) is used in the external preparation for skin of the present invention, the content thereof is preferably 0.2% by mass or more, more preferably 1% by mass in the external preparation for skin from the viewpoint of imparting an excellent ultraviolet protection effect. % Or more, more preferably 3% by mass or more, still more preferably 5% by mass or more. Further, from the viewpoint of obtaining an excellent infrared protection effect and from the viewpoint of obtaining a natural color tone that is less likely to turn white when an external preparation for skin is applied to the skin, it is preferably 30% by mass or less, more preferably 25% by mass or less. , More preferably 20% by mass or less, and even more preferably 15% by mass or less. The specific range of the content of the component (e) in the external preparation for skin is preferably 0.2% by mass or more and 30% by mass or less, more preferably 1% by mass or more and 25% by mass or less, and further preferably 3% by mass or more. It is 20% by mass or less, more preferably 5% by mass or more and 15% by mass or less.

In the external preparation for skin of the present invention, the mass ratio [{(a) + (b) + (c)} / (e)] of the total amount of the components (a) to (c) and the component (e) is determined. From the viewpoint of obtaining an excellent infrared protection effect and from the viewpoint of obtaining a natural color tone that does not easily turn white when an external preparation for skin is applied to the skin, it is preferably 0.1 or more, more preferably 0.2 or more, and further. It is preferably 0.3 or more. Further, from the viewpoint of imparting an excellent UV protection effect, it is preferably 5 or less, more preferably 3 or less, still more preferably 1 or less, still more preferably 0.5 or less. The specific range of the mass ratio [{(a) + (b) + (c)} / (e)] is preferably 0.1 or more and 5 or less, more preferably 0.1 or more and 3 or less, and further preferably 0. .2 or more and 1 or less, more preferably 0.3 or more and 1 or less, still more preferably 0.3 or more and 0.5 or less.

<Component (f): Oil agent>
The external preparation for skin of the present invention has a viewpoint of improving the applicability to the skin by dispersing the components (a) to (c) and dispersing or dissolving other compounding components, as well as the oil-in-water type or water in oil. From the viewpoint of preparing a type of external preparation for skin, it is preferable to further contain an oil agent as the component (f). As the oil agent, either a non-volatile oil (f1) or a volatile oil (f2) other than the component (e) can be used, and these can also be used in combination. When an oil-soluble ultraviolet absorber is used as the above-mentioned component (e) in the external preparation for skin of the present invention, the oil agent (f) preferably contains at least a non-volatile oil (f1) from the viewpoint of dissolving the oil-soluble ultraviolet absorber.

(Non-volatile oil (f1))
The external preparation for skin of the present invention preferably contains a non-volatile oil (f1) as the oil (f). The non-volatile oil means an oil having an evaporation amount of less than 20% at 25 ° C. for 6 hours, which is measured by the following method (1).
Method (1): A filter paper having a diameter of 90 mm is placed in a glass petri dish having a diameter of 120 mm, 1 g of a sample is placed on the filter paper, and the sample is stored in a room (25 ° C.) at 65% RH. Then, the residue of the sample after 6 hours is measured, and the amount of evaporation is calculated.

The component (f1) is preferably liquid at 25 ° C. under 1 atm. More specifically, the component (f1) has a viscosity at 25 ° C. of preferably 500 mPa · s or less, more preferably 300 mPa · s or less, still more preferably 100 mPa · s or less, and even more preferably. It is 50 mPa · s or less, preferably 5 mPa · s or more.
The viscosity was determined by using a B-type viscometer "TVB-10" (manufactured by Toki Sangyo Co., Ltd.). It can be measured under the conditions of 1, 25 ° C., 60 rpm and 1 minute.

Specific examples of the component (f1) include non-volatile oils other than the component (e) that are liquid at 25 ° C., ester oils, silicone oils, hydrocarbon oils, higher fatty acids, and higher alcohols.

Examples of the non-volatile liquid ester oil include isononyl isononanoate, isotridecyl isononanoate, isopropyl myristate, isocetyl myristate, octyldodecyl myristate, isopropyl palmitate, ethylhexyl palmitate, 2-hexyldecyl palmitate, and tri2. -Glyceryl ethylhexanoate, di2-ethylhexyl sebacate, diisopropyl sebacate, tri (caprylic acid / capric acid) glyceryl, diisostearyl malate, diethylene glycol dicaprate, neopentyl glycol dicaprate, neo di2-ethylhexanoate One or more selected from the group consisting of pentylglycol and alkyl benzoate such as alkyl benzoate (C12 to C15) can be mentioned.

Among the above, from the viewpoint of obtaining a natural color when applied to the skin and suppressing stickiness, a monoester of a fatty acid having 12 or more and 18 or less carbon atoms and a branched alcohol having 2 or more and 22 or less carbon atoms, and 6 carbon atoms. Triester of branched fatty acid of 18 or more and 18 or less and glycerin, diester of dicarboxylic acid of 2 or more and 18 or less carbon and branched alcohol of 2 or more and 18 or less carbon number, fatty acid of 6 or more and 18 or less carbon number and 2 or more and 10 carbon atoms Diesters with the following branched dialcohols, alkyl benzoates (C12 to C15) (for example, Finsolve TN; manufactured by Innospec Active Chemicals LLC) and the like are preferable, and specifically, isopropyl myristate, isosetyl myristate, octyldodecyl myristate, etc. Isopropyl palmitate, ethylhexyl palmitate, 2-hexyldecyl palmitate, glyceryl tri2-ethylhexanoate, diisopropyl sebacate, di2-ethylhexyl sebacate, diisostearyl malate, neopentyl glycol di2-ethylhexanate, One or more selected from the group consisting of neopentyl glycol dicaprate and alkyl benzoate (C12 to C15) is more preferable, and one or more selected from the group consisting of isopropyl palmitate and alkyl benzoate (C12 to C15) is more preferable. More preferred.

As the non-volatile liquid silicone oil, methylpolysiloxane is preferable from the viewpoint of suppressing stickiness when applied to the skin, and methylpolysiloxane having a viscosity at 25 ° C. of 20 mPa · s or less is more preferable.

Examples of non-volatile liquid hydrocarbon oils include liquid paraffin, light liquid isoparaffin such as hydrogenated polyisobutene, heavy liquid isoparaffin, liquid zokerite, squalane, pristane, squalene, and isohexadecane. Among these, one or more selected from the group consisting of light liquid isoparaffin and isohexadecane is preferable from the viewpoint of suppressing stickiness when applied to the skin, and more preferably light liquid isoparaffin.

Examples of the non-volatile liquid higher fatty acid include fatty acids having 12 or more and 22 or less carbon atoms, and specific examples thereof include oleic acid, isostearic acid, linoleic acid, and linoleic acid.
Examples of the non-volatile liquid higher alcohol include alcohols having 12 to 28 carbon atoms, and specific examples thereof include oleyl alcohol, 2-decyltetradecinol, dodecanol, isostearyl alcohol, and octyldodecanol. Can be mentioned.

The component (f1) is one or more selected from the group consisting of ester oils, silicone oils and hydrocarbon oils, preferably from the viewpoint of suppressing stickiness when applied to the skin, among non-volatile oils that are liquid at 25 ° C. It is more preferably one or more selected from the group consisting of ester oils and hydrocarbon oils, and even more preferably selected from the group consisting of alkyl benzoate (C12-15), isopropyl palmitate, and light liquid isoparaffin. It is one or more kinds.

When the external preparation for skin of the present invention contains the component (f1), the content thereof disperses the components (a) to (c) and disperses or dissolves other compounding components to improve the applicability to the skin. From the viewpoint of improving and preparing an oil-in-water type or water-in-oil type skin external preparation, it is preferably 1% by mass or more, more preferably 4% by mass or more, and further preferably 8% by mass or more. Further, from the viewpoint of obtaining an excellent infrared protection effect and suppressing stickiness when applied to the skin, it is preferably 99% by mass or less, more preferably 90% by mass or less, still more preferably 80% by mass or less, still more preferably. Is 50% by mass or less, more preferably 30% by mass or less. The specific range of the content of the component (f1) in the external preparation for skin is preferably 1% by mass or more and 99% by mass or less, more preferably 4% by mass or more and 90% by mass or less, and further preferably 8% by mass or more and 80% by mass. % Or less, more preferably 8% by mass or more and 50% by mass or less, still more preferably 8% by mass or more and 30% by mass or less.

When the external preparation for skin of the present invention contains the component (f1), the mass ratio of the total amount of the components (a) to (c) to the component (f1) [{(a) + (b) + (c) } / (F1)] is preferably 0.01 or more, from the viewpoint of obtaining an excellent ultraviolet protection effect, and from the viewpoint of obtaining a natural color tone without becoming white when an external preparation for skin is applied to the skin. It is preferably 0.05 or more, more preferably 0.1 or more, and prepares an oil-in-water type or a water-in-oil type skin external preparation from the viewpoint of dissolving an oil-soluble ultraviolet absorber, improving coatability, and preparing. From this point of view, it is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1 or less, still more preferably 0.5 or less. The specific range of the mass ratio [{(a) + (b) + (c)} / (f1)] is preferably 0.01 or more and 10 or less, more preferably 0.01 or more and 5 or less, and further preferably 0. It is 0.05 or more and 3 or less, more preferably 0.1 or more and 1 or less, and even more preferably 0.3 or more and 0.5 or less.

When the external preparation for skin of the present invention contains the component (e) and the component (f1), the mass ratio [(e) / (f1)] is preferably 0.01 from the viewpoint of obtaining an excellent ultraviolet protection effect. The above is more preferably 0.02 or more, further preferably 0.05 or more, still more preferably 0.1 or more, and when an oil-soluble ultraviolet absorber is used as the component (e), its dissolution. From the viewpoint of sex, it is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less. The specific range of the mass ratio [(e) / (f1)] is preferably 0.01 or more and 10 or less, more preferably 0.02 or more and 5 or less, still more preferably 0.05 or more and 3 or less, still more preferably. It is 0.1 or more and 3 or less.

(Volatile oil (f2))
In the present specification, the volatile oil is an oil agent other than the above-mentioned ultraviolet absorber (e), and the amount of evaporation at 25 ° C. for 6 hours measured by the following method (1) is 20% or more. Say something.
Method (1): A filter paper having a diameter of 90 mm is placed in a glass petri dish having a diameter of 120 mm, 1 g of a sample is placed on the filter paper, and the sample is stored in a room (25 ° C.) at 65% RH. Then, the residue of the sample after 6 hours is measured, and the amount of evaporation is calculated.

The component (f2) is preferably a volatile silicone oil, and more preferably a linear organopolysiloxane or a cyclic organopolysiloxane that is liquid and volatile at 25 ° C.
Specific examples of the linear organopolysiloxane include octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, 1,1,1,3,5,5,5-heptamethyl-3-[(trimethylsilyl) oxy. ] -Trisiloxane can be mentioned.
Examples of the cyclic organopolysiloxane include 4- to 6-membered cyclic siloxanes having an alkyl group having 1 or more and 5 or less carbon atoms as a substituent, and specific examples thereof include octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane. Can be mentioned.

Among the above, as the component (f2), cyclic organopolysiloxane is preferable, and decamethylcyclopentasiloxane is more preferable, from the viewpoint of suppressing stickiness when applied to the skin.

Commercially available volatile silicone oils that can be used as component (f2) include "KF-96A-1cs" (octamethyltrisiloxane) and "KF-96L-1.5cs" manufactured by Shin-Etsu Chemical Industry Co., Ltd. (Decamethyltetrasiloxane), "KF-96L-2cs" (Dodecamethylpentasiloxane), "KF-995" (Decamethylcyclopentasiloxane), "TMF-1.5" (1,1,1,3) 5,5,5-Heptamethyl-3-[(trimethylsilyl) oxy] -trisiloxane), "DOWNSIL SH200C Fluid 1cs" (octamethyltrisiloxane), "DOWNSIL SH200C Fluid 1.5cs" manufactured by Dow Toray Co., Ltd. (Decamethyltetrasiloxane), "DOWNSIL SH200C Fluid 2cs" (Dodecamethylpentasiloxane), "DOWNSIL SH245 Fluid" (Decamethylcyclopentasiloxane), "TSF405" (Decamethylcyclopenta) manufactured by Momentive Performance Materials. Siloxane).

When the external preparation for skin of the present invention contains the component (f2), the content thereof can be appropriately selected depending on the dosage form of the external preparation for skin, but is preferably 1% by mass or more, more preferably 5% by mass or more. , More preferably, it can be 10% by mass or more. Further, from the viewpoint of suppressing stickiness when applied to the skin, it can be preferably 85% by mass or less, more preferably 80% by mass or less, and further preferably 75% by mass or less. The specific range of the content of the component (f2) in the external preparation for skin is preferably 1% by mass or more and 85% by mass or less, more preferably 5% by mass or more and 80% by mass or less, and further preferably 10% by mass or more and 75% by mass. % Or less.

(Aqueous medium)
The external preparation for skin of the present invention is necessary from the viewpoint of dispersing or dissolving the components (a) to (c) and other compounding components, and from the viewpoint of preparing an oil-in-water type or a water-in-oil type skin external preparation. Depending on the situation, an aqueous medium can be further contained. The aqueous medium is not particularly limited as long as it can disperse or dissolve the components (a) to (c) and other compounding components, and is, for example, water; ethanol, isopropyl alcohol, butyl alcohol and the like having 4 carbon atoms. The following monohydric alcohols; low molecular weight diols having 6 or less carbon atoms such as 1,3-butylene glycol, glycerin, ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol, and triol can be mentioned. Among these, one or more selected from the group consisting of water and a monohydric alcohol having 4 or less carbon atoms is preferable, and one or more selected from the group consisting of water and ethanol is more preferable.

When the aqueous medium in the external preparation for skin is contained, the content thereof can be appropriately selected depending on the dosage form of the external preparation for skin, but is preferably 5% by mass or more, more preferably 8% by mass or more, still more preferably. It can be 10% by mass or more. Further, it can be preferably 99% by mass or less, more preferably 90% by mass or less, still more preferably 70% by mass or less, still more preferably 50% by mass or less.

<Other ingredients>
In addition to the above components, the external preparation for skin of the present invention contains other components as required, such as surfactants, ultraviolet scattering agents, antiperspirants, fragrances, moisturizers, thickeners, bactericides, and pH adjusters. , Antioxidants, preservatives and the like can also be contained.

(Manufacturing method of external preparation for skin)
The method for producing the external preparation for skin of the present invention is not particularly limited, and a known method can be appropriately used depending on the dosage form of the external preparation for skin. For example, a method of blending the components (a) to (c) and all other components and uniformly mixing them with a homogenizer, a disper, or the like can be mentioned. When blending an aqueous medium, it is also possible to use a method in which all the components other than the aqueous medium are blended, uniformly mixed with a disper or the like, then the aqueous medium is blended and further stirred and mixed with a homogenizer or the like.

[Infrared protection method for skin]
The present invention also provides a method for protecting against infrared rays of the skin by applying the external preparation for skin of the present invention to the skin. The protective method of the present invention is not particularly limited as long as it has a step of applying the external preparation for skin of the present invention to the skin.

In the protection method of the present invention, the infrared protection rate at a wavelength of 1500 nm is preferably 10% or more, more preferably 12% or more, still more preferably 15% or more. When the infrared protection rate at a wavelength of 1500 nm is in the above range, the actual feeling of heat insulation of the skin is good. The infrared protection rate (%) is a value represented by 100-X (%) when the infrared transmittance measured by a spectrophotometer is X (%), and specifically, the method described in Examples. Can be measured by.
By applying the external preparation for skin of the present invention to the skin, infrared rays can be effectively protected.

With respect to the above embodiments, the present invention further discloses the following embodiments.
<1>
The following components (a) to (c):
(A) Plate-like metal oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped metal oxides with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped metal oxides with a thickness of 180 nm or more and 200 nm or less.
It is made by blending
The blending amount of the component (a) is 5% by mass or more and 70% by mass or less, and the blending amount of the component (b) is 15% by mass or more and 75% by mass with respect to the total blending amount of the components (a) to (c) of 100% by mass. % Or less, and the blending amount of the component (c) is 5% by mass or more and 70% by mass or less, which is an external preparation for skin.
<2>
The skin external preparation of <1>, wherein the plate-shaped metal oxide is preferably one or more selected from the group consisting of plate-shaped titanium oxide and plate-shaped zinc oxide, and more preferably plate-shaped titanium oxide.
<3>
The plate-like metal oxide is preferably one or more selected from the group consisting of silicone and alkylalkoxysilane, more preferably methylpolysiloxane, dimethylpolysiloxane, methylhydrogenpolysiloxane, (alkyl acrylate / dimethicone) copolymer. The external preparation for skin of <1> or <2>, which is surface-treated with one or more selected from the group consisting of octyltriethoxysilane and.
<4>
The thickness of the component (a) is preferably 105 nm or more and 115 nm or less, the thickness of the component (b) is preferably 130 nm or more and 140 nm or less, and the thickness of the component (c) is preferably 185 nm. The external preparation for skin according to any one of <1> to <3>, which is 195 nm or less.
<5>
The average particle size of the components (a) to (c) is preferably 1 μm or more and 20 μm or less, more preferably 2 μm or more and 15 μm or less, still more preferably 2 μm or more and 12 μm or less, still more preferably 3 μm or more and 10 μm or less, still more preferably. An external preparation for skin according to any one of <1> to <4>, which is 5 μm or more and 10 μm or less.
<6>
The aspect ratios of the components (a) to (c) are preferably 10 or more and 200 or less, more preferably 10 or more and 150 or less, still more preferably 10 or more and 100 or less, still more preferably 20 or more and 100 or less, still more preferably 30. The external preparation for skin according to any one of <1> to <5>, which is 100 or more, more preferably 35 or more and 90 or less.
<7>
The compounding ratio of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total compounding amount of the components (a) to (c) satisfies the following condition 1, and preferably the following condition 2 is further satisfied. The external preparation for skin according to any one of <1> to <6>.
Condition 1: In a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total blending amount of the components (a) to (c), the blending ratio of each component is , It is within the range of the composition region surrounded by the 6 composition points shown below.
(A, b, c) = (70,15,15), (28,26,46), (5,40,55), (5,67,28), (20,68,12), (57 , 33, 10)
Condition 2: In a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total blending amount of the components (a) to (c), the blending ratio of each component is , It is within the range of the composition region surrounded by the 6 composition points shown below.
(A, b, c) = (50,28,22), (25,45,30), (25,32,43), (15,43,42), (23,55,22), (42) , 43, 15)
<8>
The total amount of the components (a) to (c) in the external preparation for skin is preferably 1% by mass or more and 35% by mass or less, more preferably 1% by mass or more and 25% by mass or less, and further preferably 1% by mass or more and 20% by mass. % Or less, more preferably 1% by mass or more and 15% by mass or less, still more preferably 1.5% by mass or more and 10% by mass or less, still more preferably 2% by mass or more and 10% by mass or less, <1> to An external preparation for skin according to any one of <7>.

<9>
The external preparation for skin according to any one of <1> to <8>, which further contains a feel-improving agent as the component (d).
<10>
The component (d) is preferably spherical inorganic particles, more preferably spherical metal oxide particles, and further preferably one or more selected from the group consisting of spherical titanium oxide particles and spherical zinc oxide particles. More preferably, the external preparation for skin of <9>, which is spherical titanium oxide particles.
<11>
The average particle size of the particles used as the component (d) is preferably 0.1 μm or more and 10 μm or less, more preferably 0.2 μm or more and 5 μm or less, and further preferably 0.5 μm or more and 2 μm or less, <9> or <. 10> External skin preparation.
<12>
The content of the component (d) is preferably 1% by mass or more and 20% by mass or less, more preferably 1% by mass or more and 15% by mass or less, still more preferably 1% by mass or more and 10% by mass or less, still more preferably 1. The external preparation for skin according to any one of <9> to <11>, which is 5% by mass or more and 10% by mass or less, more preferably 2% by mass or more and 10% by mass or less.
<13>
The mass ratio of the total amount of the components (a) to (c) to the component (d) [{(a) + (b) + (c)} / (d)] is preferably 0.1 or more and 5 or less. , More preferably 0.2 or more and 3 or less, still more preferably 0.5 or more and 2 or less, still more preferably 0.5 or more and 1.5 or less, for external use of any one of <9> to <12>. Agent.
<14>
The external preparation for skin according to any one of <1> to <13>, which further contains an ultraviolet absorber as a component (e).
<15>
Ingredient (e) is preferably an oil-soluble organic ultraviolet absorber, more preferably 2-ethylhexyl paramethoxysilicate, 4-tert-butyl-4'-methoxydibenzoylmethane, octocrylene, dimethoxybenzylene dioxoimidazo. 2-Ethylhexyl lysinepropionate, hexyl diethylaminohydroxybenzoylbenzoate, bisethylhexyloxyphenol methoxyphenyltriazine, methylenebisbenzotriazolyltetramethylbutylphenol, and 2,4,6-tris [4- (2-ethylhexyloxy) One or more selected from the group consisting of carbonyl) anilino] -1,3,5-triazine, preferably 2-ethylhexyl paramethoxysilicate, hexyl diethylaminohydroxybenzoylbenzoate, bisethylhexyloxyphenol methoxyphenyltriazine, and 2 , 4,6-Tris [4- (2-ethylhexyloxycarbonyl) anilino] -1,3,5-triazine, one or more selected from the group, more preferably 2-ethylhexyl paramethoxysilicate. The skin external preparation of <14>, which is one or more selected from the group consisting of hexyl diethylaminohydroxybenzoylbenzoate, and bisethylhexyloxyphenol methoxyphenyltriazine.
<16>
The content of the component (e) is preferably 0.2% by mass or more and 30% by mass or less, more preferably 1% by mass or more and 25% by mass or less, still more preferably 3% by mass or more and 20% by mass or less, still more preferably. <14> or <15> external preparation for skin, which is 5% by mass or more and 15% by mass or less.
<17>
The mass ratio of the total amount of the components (a) to (c) to the component (e) [{(a) + (b) + (c)} / (e)] is preferably 0.1 or more and 5 or less. , More preferably 0.1 or more and 3 or less, still more preferably 0.2 or more and 1 or less, still more preferably 0.3 or more and 1 or less, still more preferably 0.3 or more and 0.5 or less, <14>. An external preparation for skin according to any one of ~ <16>.
<18>
The external preparation for skin according to any one of <1> to <17>, which further contains an oil agent as a component (f) and preferably contains a non-volatile oil (f1).
<19>
The component (f1) is selected from one or more selected from the group consisting of ester oils, silicone oils, hydrocarbon oils, higher fatty acids, and higher alcohols, and more preferably selected from the group consisting of ester oils, silicone oils, and hydrocarbon oils. One or more, more preferably one or more selected from the group consisting of ester oils and hydrocarbon oils, even more preferably selected from the group consisting of alkyl benzoate (C12-15), isopropyl palmitate, and light liquid isoparaffin. <18> external skin preparation, which is one or more.
<20>
The content of the component (f1) is preferably 1% by mass or more and 99% by mass or less, more preferably 4% by mass or more and 90% by mass or less, still more preferably 8% by mass or more and 80% by mass or less, still more preferably 8% by mass. % Or more and 50% by mass or less, more preferably 8% by mass or more and 30% by mass or less, <18> or <19> for external use on the skin.
<21>
The mass ratio of the total amount of the components (a) to (c) to the component (f1) [{(a) + (b) + (c)} / (f1)] is preferably 0.01 or more and 10 or less. , More preferably 0.01 or more and 5 or less, still more preferably 0.05 or more and 3 or less, still more preferably 0.1 or more and 1 or less, still more preferably 0.3 or more and 0.5 or less, <18>. An external preparation for skin according to any one of ~ <20>.
<22>
The mass ratio [(e) / (f1)] is preferably 0.01 or more and 10 or less, more preferably 0.02 or more and 5 or less, still more preferably 0.05 or more and 3 or less, still more preferably 0.1 or more. An external preparation for skin according to any one of <18> to <21>, which is 3 or less.
<23>
Volatile oil (f2) as the component (f), preferably volatile silicone oil, more preferably linear organopolysiloxane and cyclic organopolysiloxane, which are liquid and volatile at 25 ° C., more preferably cyclic. <18> to <containing an organopolysiloxane, more preferably a 4- to 6-membered cyclic siloxane having an alkyl group having 1 or more and 5 or less carbon atoms as a substituent, and even more preferably a decamethylcyclopentasiloxane. 22> Any one of the external preparations for skin.
<24>
The content of the component (f2) is preferably 1% by mass or more and 85% by mass or less, more preferably 5% by mass or more and 80% by mass or less, and further preferably 10% by mass or more and 75% by mass or less, <23>. External preparation for skin.

<25>
An external preparation for skin, the following components (a) to (c):
(A) Plate-shaped titanium oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped titanium oxide with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped titanium oxide with a thickness of 180 nm or more and 200 nm or less.
It is made by blending
The average particle size of the components (a) to (c) is 3 μm or more and 10 μm or less.
The blending amount of the component (a) is 5% by mass or more and 70% by mass or less, and the blending amount of the component (b) is 15% by mass or more and 75% by mass with respect to the total blending amount of the components (a) to (c) of 100% by mass. % Or less, and the blending amount of the component (c) is 5% by mass or more and 70% by mass or less.
An external preparation for skin, wherein the total amount of the components (a) to (c) in the external preparation for skin is 2% by mass or more and 10% by mass or less.
<26>
An external preparation for skin, the following components (a) to (c):
(A) Plate-shaped titanium oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped titanium oxide with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped titanium oxide with a thickness of 180 nm or more and 200 nm or less.
It is made by blending
The average particle size of the components (a) to (c) is 3 μm or more and 10 μm or less.
The compounding ratio of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total compounding amount of the components (a) to (c) satisfies the following condition 1.
An external preparation for skin, wherein the total amount of the components (a) to (c) in the external preparation for skin is 2% by mass or more and 10% by mass or less.
Condition 1: In a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total blending amount of the components (a) to (c), the blending ratio of each component is , It is within the range of the composition region surrounded by the 6 composition points shown below.
(A, b, c) = (70,15,15), (28,26,46), (5,40,55), (5,67,28), (20,68,12), (57 , 33, 10)
<27>
An external preparation for skin, the following components (a) to (c):
(A) Plate-shaped titanium oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped titanium oxide with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped titanium oxide with a thickness of 180 nm or more and 200 nm or less.
It is made by blending
The average particle size of the components (a) to (c) is 3 μm or more and 10 μm or less.
The compounding ratio of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total compounding amount of the components (a) to (c) satisfies the following condition 2.
An external preparation for skin, wherein the total amount of the components (a) to (c) in the external preparation for skin is 2% by mass or more and 10% by mass or less.
Condition 2: In a three-phase diagram showing the mass% of the component (a), the component (b) and the component (c) with respect to 100% by mass of the total blending amount of the components (a) to (c), the blending ratio of each component is , It is within the range of the composition region surrounded by the 6 composition points shown below.
(A, b, c) = (50,28,22), (25,45,30), (25,32,43), (15,43,42), (23,55,22), (42) , 43, 15)
<28>
Further, as the component (d), one or more kinds of feel improvers selected from the group consisting of spherical titanium oxide particles and spherical zinc oxide particles are contained in an amount of 2% by mass or more and 10% by mass or less.
It contains 5% by mass or more and 15% by mass or less of an oil-soluble organic ultraviolet absorber as the component (e).
Any one of <25> to <27> containing 8% by mass or more and 50% by mass or less of one or more non-volatile oils (f1) selected from the group consisting of ester oils and hydrocarbon oils as the component (f). Skin external preparation.
<29>
The external preparation for skin according to any one of <1> to <28>, wherein the dosage form is liquid, gel-like, or cream-like.
<30>
An external preparation for the skin according to any one of <1> to <29>, which is a skin cosmetic, preferably a sunscreen cosmetic, a suntan, or a makeup base cosmetic.
<31>
A method for protecting the skin from infrared rays by applying the external preparation for skin according to any one of <1> to <30> to the skin.
<32>
The method of <31>, wherein the infrared protection rate at a wavelength of 1500 nm is preferably 10% or more, more preferably 12% or more, still more preferably 15% or more.

Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to the scope of the Examples. In this example, various measurements and evaluations were carried out by the following methods.

(Measurement of thickness)
The thickness of the plate-shaped titanium oxide used as the components (a) to (c) is accelerated by accelerating the components (a) to (c) using a scanning electron microscope (“VE-9800” manufactured by KEYENCE CORPORATION). It was obtained by observing under the conditions of voltage: 10 keV and observation magnification: 10,000 times, measuring the thickness of 50 particles in the observed image, and calculating the average value per number.

(Measurement of average particle size and aspect ratio)
The average particle size of the plate-shaped titanium oxide used as the components (a) to (c) and the spherical titanium oxide used as the component (d) is determined by a laser diffraction / scattering type particle size distribution measuring device (Horiba Seisakusho Co., Ltd.). Using LA920 ”), the average particle size was defined as the value of the median diameter (D50) measured with an aqueous dispersion having a relative refractive index of 2.0 and a particle size reference volume.
The aspect ratio of the plate-shaped titanium oxide used as the components (a) to (c) was calculated by (average particle size / thickness).

[Evaluation (1): Infrared protection rate, color tone when applied to the skin, and comprehensive evaluation]
(Infrared protection rate)
28.5 mg of the external preparation for skin of each example was applied to a 5 cm × 5 cm polymethyl methacrylate resin (PMMA) substrate (“HD6” manufactured by HelioScreen) and dried for 15 minutes to prepare a sample for measurement. Similarly, glycerin was applied to the PMMA substrate and dried for 15 minutes, which was used as a control sample. For each of the measurement sample and the control sample, the transmittance at a wavelength of 1500 nm was measured in the integrating sphere mode with a spectrophotometer (“UV-3600” manufactured by Shimadzu Corporation). The value obtained by dividing the transmittance of the measurement sample by the transmittance of the control sample was defined as the transmittance X (%), and 100-X (%) was defined as the infrared protection rate. The larger this value is, the higher the infrared protection effect is.

(Tint when applied to the skin)
^{Regarding the color tone immediately after applying 2 mg / cm 2 of the} external preparation for skin of each example to 2 places on the forearms of 4 subjects, 1 point was given for a very bad case and 5 points for a very good case, and 0 according to the following evaluation criteria. It was evaluated on a scale of 10 in 5 point increments. Evaluation was performed by two specialized panelists, and the average score (rounded to the first decimal place) was used as the evaluation score.
<Evaluation criteria>
1: Very bad 2: Bad 3: Neither 4: Good 5: Very good

(Comprehensive evaluation)
In the evaluation results shown in Table 1, those with an evaluation score of 3.6 or more when applied to the skin are ranked A, those with a score of 3.0 or more and 3.5 or less are ranked B, and those with an evaluation score of 2.5 or more 2 Those having a value of 9.9 or less were given a C rank, and those having a value of 2.4 or less were given a D rank. Furthermore, Table 1 shows the results of one rank up for those with an infrared protection rate of 15% or more and one rank for those with an infrared protection rate of less than 15% as a comprehensive evaluation. The overall evaluation was a 6-grade evaluation of A +, A, B, C, D and D-.

[Evaluation (2): Color and transparency]
When the external preparation for skin of each example is applied to the skin, the color is biased toward red, blue, or green, and there is no sense of transparency and the appearance is whitish, which is natural. Whether or not the hue was realized was evaluated by the following method.
^{The color and transparency when 2 mg / cm 2 of an} external preparation for skin was applied to each of the four parts of the forearm having different skin colors were visually observed and evaluated on a scale of 10 in 0.5 point increments according to the following evaluation criteria. Evaluation was performed by two specialized panelists, and the average score (rounded to the first decimal place) was used as the evaluation score.
For the four items of redness, blueness, greenness, and transparency, pass if there are no items with an evaluation score of less than 2.0 and there are two or more items with an evaluation score of 3.0 or more, and the others are not accepted. It was passed.
<Evaluation criteria>
(Reddish)
5: Less redness 4: Slightly less redness 3: Neither 2: Slightly reddish 1: Strong redness (blue)
5: Less bluish 4: Slightly less bluish 3: Neither 2: Slightly bluish 1: Strong bluish (greenish)
5: Less green 4: Slightly less green 3: Neither 2: Slightly green 1: Strong green (transparency)
5: There is a sense of transparency 4: There is a sense of transparency 3: Neither 2: There is a sense of transparency 1: There is no sense of transparency

Production Example 1 (Production of plate-shaped titanium oxide 1)
Untreated plate-shaped titanium oxide (CQV "Featheleve PT-7401K", thickness 112 nm, aspect ratio 126, average particle size 14.1 μm) is pulverized with a built-in impact classifier (ACM manufactured by Hosokawa Micron Co., Ltd.) After the pulverization treatment using -10 ”), a coating treatment was carried out with a (alkyl acrylate / dimethicone) copolymer to obtain a plate-shaped titanium oxide 1 having a thickness of 112 nm, an aspect ratio of 80 and an average particle size of 9.0 μm.

Production Example 2 (Production of plate-shaped titanium oxide 2)
As the untreated plate-shaped titanium oxide, "Featheleve PT-7801K" (thickness 134 nm, aspect ratio 95, average particle size 12.8 μm) manufactured by CQV was used instead of "Feathereve PT-7401K" manufactured by CQV. Except for this, the same treatment as in Production Example 1 was carried out to obtain plate-shaped titanium oxide 2 having a thickness of 134 nm, an aspect ratio of 64, and an average particle size of 8.6 μm.

Production Example 3 (Production of plate-shaped titanium oxide 3)
As the untreated plate-shaped titanium oxide, "Featheleve PT-7901K" (thickness 191 nm, aspect ratio 58, average particle size 11.1 μm) manufactured by CQV was used instead of "Featheleve PT-7401K" manufactured by CQV. Except for this, the same treatment as in Production Example 1 was carried out to obtain plate-shaped titanium oxide 3 having a thickness of 191 nm, an aspect ratio of 44, and an average particle size of 8.5 μm.

Examples 1 to 12 and Comparative Examples 1 to 8 (manufacturing and evaluation of external preparations for skin)
The ingredients shown in Table 1 were blended and mixed uniformly using a homogenizer to prepare a skin external preparation having the composition shown in Table 1. The obtained external preparation for skin was evaluated by the above method. The results are shown in Table 1. The blending amount shown in Table 1 is the amount of the active ingredient (mass%) of each component.

The ingredients in Table 1 are as follows.
* 1: Plate-shaped titanium oxide 1 obtained in Production Example 1
* 2: Plate-shaped titanium oxide 2 obtained in Production Example 2
* 3: Plate-shaped titanium oxide 3 obtained in Production Example 3
* 4: "ST-750EC" manufactured by Titan Kogyo Co., Ltd., spherical titanium oxide, average particle size 1000 nm, aspect ratio 1.0
* 5: BASF's "Ubinal MC80", 2-ethylhexyl paramethoxycinnamate * 6: Kao Corporation's "Exepearl IPP", isopropyl palmitate * 7: Momentive Performance Materials'"TSF405", Decamethylcyclopentasiloxane

From Table 1, the external preparations for skin of Examples 1 to 12 can have both an infrared ray protective effect and a natural color when applied to the skin. Among them, Examples 1, 3, 4, 6, 8 and 9 in which the blending ratios of the components (a) to (c) satisfy the above condition 1 are more preferable because the overall evaluation is A or more, and the implementation satisfying the above condition 2. Examples 4 and 6 have a comprehensive evaluation of A +, which is more preferable.
On the other hand, the external preparations for skin of Comparative Examples 1 to 8 did not have a sufficient effect in at least one of the infrared protective effect and the natural color when applied to the skin.

The notation of A +, A, B, C, D and D- shown in the three-phase diagram of FIG. 1 indicates the components (a) to (c) corresponding to the external preparations for skin of Examples 1 to 12 and Comparative Examples 1 to 8. ), The comprehensive evaluation is shown.

1 The blending amount of the component (a) is 5% by mass or more and 70% by mass or less, and the blending amount of the component (b) is 15% by mass or more and 75% by mass or less with respect to the total blending amount of 100% by mass of the components (a) to (c). Composition region 2 in which the blending amount of the component (c) is 5% by mass or more and 70% by mass or less Composition region satisfying condition 1 Composition region satisfying condition 2

Claims

The following components (a) to (c):
(A) Plate-like metal oxide with a thickness of 100 nm or more and 120 nm or less,
(B) Plate-shaped metal oxides with a thickness of 125 nm or more and 145 nm or less, and (c) Plate-shaped metal oxides with a thickness of 180 nm or more and 200 nm or less.
It is made by blending
The blending amount of the component (a) is 5% by mass or more and 70% by mass or less, and the blending amount of the component (b) is 15% by mass or more and 75% by mass with respect to the total blending amount of the components (a) to (c) of 100% by mass. % Or less, and the blending amount of the component (c) is 5% by mass or more and 70% by mass or less, which is an external preparation for skin.
The skin external preparation according to claim 1, wherein the plate-shaped metal oxide is plate-shaped titanium oxide.
The skin external preparation according to claim 1 or 2, wherein the average particle diameters of the components (a) to (c) are 1 μm or more and 20 μm or less.
The skin external preparation according to any one of claims 1 to 3, wherein the total amount of the components (a) to (c) in the skin external preparation is 1% by mass or more and 35% by mass or less.
The skin external preparation according to any one of claims 1 to 4, further containing a feel-improving agent as the component (d).
The external preparation for skin according to any one of claims 1 to 5, further containing an ultraviolet absorber as a component (e).
The skin external preparation according to any one of claims 1 to 6, further containing an oil agent as the component (f).
The external preparation for skin according to any one of claims 1 to 7, which is a skin cosmetic.
A method for protecting the skin from infrared rays by applying the external preparation for skin according to any one of claims 1 to 8 to the skin.