Boehmite composite powder, and cosmetic containing the same

Abstract

To provide novel boehmite composite powder having ultraviolet absorbability, and to provide cosmetics containing the boehmite composite powder.SOLUTION: Provided are: boehmite composite powder containing boehmite and an ultraviolet absorber attached to a surface of the boehmite; and cosmetics containing the boehmite composite powder.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a boehmite composite powder having ultraviolet absorption ability and a cosmetic containing the boehmite composite powder.

Background Art

[0002] When the skin is irradiated with ultraviolet rays, it induces sunburn, DNA cleavage, collagen denaturation, etc., which causes skin aging. Therefore, cosmetics containing ultraviolet ray protectants are used. As a kind of ultraviolet ray protectant, inorganic ultraviolet ray shielding agents are known. The inorganic ultraviolet ray shielding agent is a fine particle metal oxide having an average particle diameter of 0.1 μm or less, which is composed of titanium oxide, fine particle titanium oxide, zinc oxide, fine particle zinc oxide, etc. that can reflect ultraviolet rays, and has relatively high safety for shielding ultraviolet rays on the skin surface.

[0003] However, since the inorganic ultraviolet ray shielding agent has a high refractive index, its transparency is low. In addition, when it is blended in a large amount to enhance the ultraviolet ray prevention effect, there are drawbacks such as the skin looking whitish (whitening), poor slipperiness, and the occurrence of squeaking and roughness. Therefore, an ultraviolet ray protectant having excellent transparency and usability and further having a high ultraviolet ray prevention effect is desired. For example, Patent Document 1 proposes zinc oxide-containing spherical silica having good smoothness and fluidity and high transparency, and Patent Document 2 proposes titania nano fine particles having coatability, ultraviolet ray shielding property and transparency.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to provide a boehmite composite powder having a novel ultraviolet absorption ability and a cosmetic containing the boehmite composite powder.

Means for Solving the Problems

[0006] The main means for solving the problems of the present invention are as follows. 1. A boehmite composite powder characterized by having boehmite and an ultraviolet absorber attached to the surface of the boehmite. 2. The boehmite composite powder according to 1, wherein the boehmite is plate-shaped. 3. The ultraviolet absorber is one or more selected from the group consisting of para-aminobenzoic acid-based ultraviolet absorbers, cinnamic acid-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, dibenzoylmethane-based ultraviolet absorbers, triazine-based ultraviolet absorbers, benzoic acid-based ultraviolet absorbers, and salicylic acid-based ultraviolet absorbers. The boehmite composite powder according to 1 or 2. 4. A cosmetic containing the boehmite composite powder according to any one of 1 to 3.

Effects of the Invention

[0007] In the boehmite composite powder of the present invention, an ultraviolet absorber is attached to the surface thereof, and the ultraviolet absorber can absorb ultraviolet rays. In the boehmite composite powder of the present invention, various ultraviolet absorbers can be attached to the surface thereof, and the ultraviolet absorber to be attached can absorb ultraviolet rays in a desired wavelength band. Since the refractive index of the boehmite in the boehmite composite powder of the present invention is low, whitening is less likely to occur when blended in a cosmetic. In addition, the plate-shaped boehmite is smooth when applied, and a cosmetic having excellent usability can be obtained.

Modes for Carrying Out the Invention

[0008] The boehmite composite powder of the present invention has boehmite and an ultraviolet absorber attached to the surface of the boehmite. "Boehmite" Boehmite is aluminum oxyhydroxide represented by AlOOH, with the cosmetic display name "Aluminum Hydroxide Oxide" and INCI "Aluminum Hydroxide Oxide". The shape of the boehmite used in the present invention is not particularly limited. For example, when incorporated into cosmetics, it is preferably in a plate-like shape. The average particle size is preferably 0.5 to 10 μm, and the aspect ratio is preferably 2 to 150. More preferably, the average particle size is 1 to 8 μm and the aspect ratio is 5 to 100. Particularly preferably, the average particle size is 3 to 5 μm and the aspect ratio is 10 to 30. The average particle size means the median diameter (50% diameter) in the particle size distribution measured by the laser diffraction / scattering method. Also, the aspect ratio is calculated as particle diameter / thickness from SEM photographs. In this specification, the description of A to B (A and B are numerical values) means a numerical range including A and B, that is, A or more and B or less.

[0009] "Ultraviolet absorber" The ultraviolet absorber can be used without particular limitation. For example, · Para-aminobenzoic acid-based ultraviolet absorbers such as hexyl diethylaminohydroxybenzoyl benzoate · Cinnamic acid-based ultraviolet absorbers such as ethylhexyl methoxycinnamate, isooctyl dimethoxycinnamate glyceride, and diethanolamine salt of p-methoxyhydroxycinnamic acid · Benzophenone-based ultraviolet absorbers such as 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfuric acid, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,4-dihydroxybenzophenine, 2,2',4,4'-tetrahydroxybenzophenone, and 2-hydroxy-4-N-octyloxybenzophenone · Dibenzoylmethane-based ultraviolet absorbers such as 4-t-butyl-4'-methoxydibenzoylmethane, 4-isopropyldibenzoylmethane, and butyl methoxydibenzoylmethane · Triazine-based UV absorbers such as bis(ethylhexyl)oxyphenol methoxyphenyltriazine and ethylhexyltriazone · Benzoic acid-based UV absorbers such as para-aminobenzoic acid (hereinafter abbreviated as PABA), methyl methoxybenzoate, ethyl dihydroxypropyl PABA, ethylhexyl dimethyl PABA, and glyceryl PABA · Salicylic acid-based UV absorbers such as ethylhexyl salicylate, homomenthyl salicylate, and triethanolamine salicylate · Benzalmalonate-based UV absorbers such as dioctyl methoxybenzylidene malonate and polysilicone-15 One or more selected from the group consisting of the above can be used.

[0010] It is preferable to use a combination of a UV absorber that can absorb the UV-A region (wavelength 320 - 400 nm) and a UV absorber that can absorb the UV-B region (wavelength 280 - 320 nm), because a high UV protection effect can be exhibited in a wide UV region. In particular, it is preferable to combine ethylhexyl methoxycinnamate as a UV absorber in the UV-B region and hexyl diethylaminohydroxybenzoyl benzoate as a UV absorber in the UV-A region from the viewpoint of the UV protection effect. Further, when using ethylhexyl methoxycinnamate and hexyl diethylaminohydroxybenzoyl benzoate, if ethylhexyl methoxycinnamate is blended in an amount of 2 times or more with respect to hexyl diethylaminohydroxybenzoyl benzoate, hexyl diethylaminohydroxybenzoyl benzoate can be heated and dissolved in liquid ethylhexyl methoxycinnamate, and by simply mixing and stirring this dissolved product with boehmite, the boehmite composite powder of the present invention with two kinds of UV absorbers attached to the surface of boehmite can be obtained, which is preferable.

[0011] The weight ratio of boehmite to the ultraviolet absorber in the boehmite composite powder of the present invention (boehmite:ultraviolet absorber) is not particularly limited, and for example, it can be 50:50 to 99:1, preferably 60:40 to 98:2, more preferably 70:30 to 95:5, and even more preferably 80:20 to 90:10.

[0012] · Manufacturing method The manufacturing method of the boehmite composite powder of the present invention is not particularly limited, and for example, the following methods can be mentioned. In the case of wet treatment, the ultraviolet absorber is dissolved in an organic solvent such as ethanol to prepare a solution with a solid content concentration of about 10 (w / w)%. Boehmite is added to this solution to a concentration of about 30 (w / w)%, and after uniformly mixing, a vacuum dryer, a stirring type vacuum dryer (double cone type rotary dryer, reverse cone type stirring dryer), a spray dryer, etc. are used to remove and dry the organic solvent. As a method for removing the organic solvent, it is preferable to use vacuum drying from the viewpoints that many ultraviolet absorbers have a relatively low heat-resistant temperature and that organic solvent recovery is possible and the manufacturing cost can be suppressed. In the case of dry treatment, while stirring boehmite with a Henschel mixer, ball mill, double cone type mixer, reverse cone type mixer, V-type mixer, etc., an organic solvent in which the ultraviolet absorber is dissolved to a solid content concentration of about 50 (w / w)% is dropped or sprayed, and then the organic solvent is removed.

Examples

[0013] Hereinafter, the present invention will be described in detail based on examples, but the present invention is not limited thereto.

[0014] · Boehmite Manufactured by Dainippon Chemical Industry Co., Ltd., "Boehmite Powder (Plate Grade)" Average particle size 3 - 5 μm, aspect ratio (particle size / thickness) 10 - 30 · Ultraviolet absorber A Diethylamino hydroxybenzoyl benzoic acid hexyl · Ultraviolet absorber B Ethylhexyl methoxycinnamate · Talc Manufactured by Asada Flour Milling Co., Ltd., JA-46R Average particle diameter: 7 - 11 μm, aspect ratio (particle diameter / thickness): 50 · Synthetic phlogopite, manufactured by Miyoshi Kasei Co., Ltd., MiyoSYN Fine Average particle diameter: 8 - 12 μm, aspect ratio (particle diameter / thickness): 55 - 65 · Alumina, prepared by firing boehmite. Average particle diameter: 3 - 5 μm, aspect ratio (particle diameter / thickness): 10 - 30

[0015] Ultraviolet absorber A and ultraviolet absorber B were weighed to the amounts (g) shown in Table 1, 300 mL of ethanol was added and dissolved. Boehmite was added in the amount (g) shown in Table 1, and the mixture was stirred. Using a rotary evaporator, ethanol was removed by drying under reduced pressure, and then dried in a dryer at 35°C for 10 hours to obtain the composite powders of Examples 1 - 5. Composite powders of Comparative Examples 1 - 3 were obtained in the same manner except that talc, synthetic phlogopite, and alumina were used instead of boehmite.

[0016] The following evaluations were performed on the obtained composite powders. The results are shown in Table 1. (Measurement method and evaluation criteria for ultraviolet shielding effect) The composite powder was uniformly applied to a PMMA plate (manufactured by HelioScreen Laboratoire) at 1.3 mg / cm 2 using a cheek brush, and SPF and UVAPF were measured using an SPF analyzer (manufactured by Labsphere, model name: UV - 2000S). A higher value of SPF and UVAPF means a higher ultraviolet shielding effect.

[0017] Ultraviolet shielding effect (UVB) ◎: SPF 160 or more ○: SPF 100 or more and less than 160 △: SPF 40 or more and less than 100 ×: SPF less than 40 Ultraviolet shielding effect (UVAPF) ◎: UVA 50 or more ○: UVA 40 or more and less than 50 △: UVA is more than 30 and less than 40 ×: UVA is less than 30

[0018] (Evaluation Criteria for Dispersion State) The dispersion state was visually evaluated for the sample state. ◎: Without lumps and uniformly dispersed ○: With very few lumps and uniformly dispersed △: With lumps and not uniformly dispersed (Evaluation Criteria for Use Feeling (Slipperiness)) For the use feeling (slipperiness), 1 g of the sample was taken on the back of the hand and the feeling when slid with the index finger was evaluated by sensory evaluation. ◎: Without stickiness at all, with very good slipperiness and no resistance felt when sliding ○: With almost no stickiness felt, with good slipperiness and no resistance felt when sliding △: Feeling sticky, difficult to slide and resistance felt when sliding

[0019] (Evaluation Criteria for Finish (Uniformity)) For the finish (uniformity), 1 g of the sample was taken on the back of the hand, slid with the index finger, and the state was visually evaluated. ◎: Without unevenness and uniformly and beautifully finished ○: With slight unevenness but uniformly finished △: With unevenness and not uniformly finished

[0020]

Table 1

Claims

1. having boehmite and an ultraviolet absorber attached to the surface of the boehmite, wherein the ultraviolet absorber is at least one selected from the group consisting of para-aminobenzoic acid-based ultraviolet absorbers, cinnamic acid-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, dibenzoylmethane-based ultraviolet absorbers, triazine-based ultraviolet absorbers, benzoic acid-based ultraviolet absorbers, and salicylic acid-based ultraviolet absorbers, a boehmite composite powder.

2. The boehmite composite powder according to claim 1, wherein the boehmite is plate-shaped.

3. A cosmetic containing the boehmite composite powder according to claim 1 or 2.

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