Hydroxyapatite having soft-focus effect

Abstract

To provide hydroxyapatite having a superior soft-focus effect.SOLUTION: A spherical hydroxyapatite having a superior soft-focus effect satisfies one or more of the following conditions: the Ca / P (molar ratio) is 1.4-1.8; the half width at d=2.814 Å in X-ray diffraction is 0.5° or less; the BET specific surface area is 60 m2 / g or less; the particle diameter (median diameter: d50) is 10 μm or less; the pH of a 10 wt.% suspension is 6 to 12; the total transmittance is 80% or more and the haze value is 35% or more; the oil absorption is 250 mL / 100 g or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to the soft focus effect of spherical hydroxyapatite.

Background Art

[0002] The soft focus effect (light scattering effect) that makes wrinkles, pores, etc. less noticeable has attracted attention, and silica, talc, titanium oxide, mica, etc. have been used. Patent Document 1 and Patent Document 2 disclose the soft focus effect of silica. However, silica has a high oil absorption capacity and absorbs oil components when blended into cosmetics. Therefore, when in a liquid state, it gels over time and it is difficult to maintain fluidity. Furthermore, its harmful effects on health (irritation, carcinogenicity, etc.) have been pointed out (Non-Patent Document 1). It has been confirmed that some talc contains asbestos (Non-Patent Document 2), and titanium oxide used in foundations, etc. has been found to cause the promotion of squalene oxidation (Non-Patent Document 3). Therefore, attention has been focused on hydroxyapatite with excellent biocompatibility. Hydroxyapatite [Ca 10 (PO4)6(OH)2 or Ca 10-Z (HPO4) Z (PO4) 6-Z (OH) 2-Z ·nH2O)] (hereinafter HAP) is a major constituent of human bone and teeth. When implanted in the living body, it has good affinity with the living body and extremely good chemical bonding properties with natural bone. Therefore, it is used as a material for artificial bone, artificial teeth, etc. It is also used as a column packing material for chromatography by taking advantage of its good affinity with proteins.

[0003] Patent Document 3 reports the production method of plate-like crystal hydroxyapatite as a cosmetic pigment, which has appropriate hiding power, good adhesion and ductility, and a natural finish. However, if the addition amount is increased to obtain the effect alone, concerns such as white floating may arise.

[0004] Patent Document 4 discloses a method for producing a hydroxyapatite pigment having a plate-like crystal shape and a formulation of a foundation, but data such as the feeling of use is insufficient and the actual effect is unclear.

Prior Art Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] Against such a background, an object of the present invention is to provide hydroxyapatite that is blended into cosmetics and the like, has high safety, and is excellent in a soft focus effect without white floating.

Means for Solving the Problems

[0007] As a result of intensive research efforts, the inventors of the present invention, in order to solve the above problems, have a Ca / P (molar ratio) = 1.4 to 1.8, an X-ray diffraction analysis result with a half-value width of d = 2.814 Å of 0.5° or less, and a BET specific surface area of 60 m 2Provided is spherical hydroxyapatite having an excellent soft focus effect satisfying any one of the following conditions: particle size (median diameter: d50) of 10 μm or less, pH of a 10 wt% suspension of 6 to 12, total transmittance of 80% or more and haze value of 35% or more, and oil absorption of 250 mL / 100 g or less.

Advantages of the Invention

[0008] The hydroxyapatite of the present invention has high safety and biocompatibility and exhibits a soft focus effect without white turbidity. When incorporated into cosmetics, it has little effect on fluidity, and can be incorporated into makeup cosmetics including hair cosmetics such as pharmaceuticals, quasi-drugs, and cosmetics (lipstick, eyeshadow, foundation, nail enamel, mascara, hair treatment, hair liquid, setting lotion, etc.) and formulated. For example, addition to dosage forms such as oily solid, oily liquid, solid, cream, paste, emulsion, lotion, powder, powder solid, etc. is conceivable.

Modes for Carrying Out the Invention

[0009] As an embodiment, the hydroxyapatite of the present invention is spherical (referred to as spherical HAP), preferably having a Ca / P molar ratio of 1.4 to 1.8, more preferably 1.5 to 1.8, still more preferably 1.6 to 1.8. The X-ray diffraction analysis result preferably has a half-value width of d = 2.814 Å of 0.5° or less, more preferably 0.4° or less, still more preferably 0.3° or less, and the BET specific surface area is 60 m 2 / g or less, more preferably 50 m 2 / g or less, still more preferably 48 m 2Hereinafter, the particle size (median diameter: d50) is preferably 10 μm or less, more preferably 8 μm or less, still more preferably 6 μm or less. The pH of the liquid in which spherical HAP is suspended at 10 wt% is preferably 6 to 12, more preferably 6 to 9, still more preferably 6 to 8. The total transmittance is preferably 80% or more, more preferably 85% or more, still more preferably 88% or more. The haze value is preferably 35% or more, more preferably 45% or more, still more preferably 65% or more. The oil absorption amount is preferably 250 mL / 100 g or less, more preferably 200 mL / 100 g or less, still more preferably 150 mL / 100 g or less.

[0010] Incidentally, the spherical HAP of the present invention can be produced by a normal production method (wet method / spray drying) (see the following examples), but commercially available products can also be used (for example, "Hydroxyapatite (HAP-SP)": manufactured by Taihei Chemical Industry Co., Ltd.).

Examples

[0011] Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, and it is of course possible to appropriately modify and implement it within the range that conforms to the gist of the foregoing and following descriptions, and all of them are included in the technical scope of the present invention.

[0012] 〔Method〕 〈Method for measuring pH〉 A sample was weighed and a 10 wt% suspension was prepared with purified water, and the pH was measured.

[0013] 〈Method for measuring BET specific surface area〉 The measurement was performed by the BET multipoint method. The pretreatment was performed with BELPREP VAC II (manufactured by Microtrac·BEL). The measurement of the BET specific surface area was performed with BELSORP-mini II (manufactured by Microtrac·BEL), and the results of the BET specific surface area were analyzed with BEL Master TM software.

[0014] 〈Method for measuring particle size (median diameter: d50)〉 The measurement was performed using MT3300EX II (manufactured by Microtrac Bell) (with ultrasonic treatment).

[0015] 〈Method for measuring Ca / P molar ratio〉 The measurement was carried out using an ICP emission spectrometer (PS3520VDD II, manufactured by Hitachi High-Tech), and the Ca / P molar ratio was calculated by the calibration curve method.

[0016] 〈Method for measuring full width at half maximum〉 The measurement was performed by crystal structure analysis using a powder X-ray diffractometer MiniFlex600-C (manufactured by Rigaku) to obtain the full width at half maximum. The measurement conditions were: X-ray generator: 40 kV, 15 mA, scan speed: 2.00° / min, step width: 0.02°, scan axis: 2θ / θ, scan range: 3 - 80°.

[0017] 〈Method for measuring oil absorption〉 The measurement was carried out with reference to the refined linseed oil method of JIS standard (JIS K5101-13-1). 1 g of the sample was weighed and transferred onto a glass plate. Linseed oil (reagent grade 1, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was put into a 25 mL burette, and several drops were added onto the sample and then thoroughly kneaded with a palette knife. After forming a lump, the dropping amount was adjusted appropriately until the paste had a smooth hardness, which was taken as the end point. Oil absorption (mL / 100 g) = (dropping amount of linseed oil (mL) / sample amount (g)) × 100

[0018] 〈Method for measuring haze value〉 1.9 g of silicone oil (KP-545, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.1 g of the sample were added to a deep tube, and stirred at a rotation speed of 40 rpm using a mini rotator (MINI ROTATOR ACR-100, manufactured by AS ONE Corporation) to prepare a 5 wt% paste. This 5 wt% paste was dropped onto a slide glass (drainage 1.0 mm, manufactured by Mutoh Chemical Co., Ltd.), and coated using a bar coater (non-wire bar coater φ10×250 mm (#10 gauge), manufactured by OSD System Products Co., Ltd.) so that the film thickness was 25 μm. This was left standing at room temperature for 4 hours to dry, and used as a slide glass for measurement. The haze value was measured using an ultraviolet-visible-near-infrared spectrophotometer (V-780, manufactured by JASCO Corporation, light source: deuterium lamp and halogen lamp) equipped with an integrating sphere unit. According to the attached haze value calculation program, the total light transmittance (hereinafter Tt) and diffuse transmittance (hereinafter Td) in the wavelength range of 380 to 780 nm (visible region) were measured, and the haze value was calculated. The calculation formula is as follows. · Install the sample thin film and the standard white board for measurement TIFF2025109970000001.tif9128 · Install the sample thin film for measurement (the standard white board is not installed) TIFF2025109970000002.tif9138 · Measure without installing the sample thin film and the standard white board TIFF2025109970000003.tif10138 Td(%) = sample scattering rate - apparatus scattering rate × (Tt / 100) S(λ): light source TIFF2025109970000004.tif955 Haze value = (Tt / Td) × 100

[0019] A high Tt indicates that a natural skin color with a transparent feeling that does not show white floating can be reproduced without overly concealing the substrate. In addition, a high haze value indicates that it has an excellent soft focus effect.

Example

[0020] (Wet method / spray drying: manufacturing method of spherical HAP) Calcium hydroxide (reagent grade, manufactured by FUJIFILM Wako Pure Chemical Corporation) 73.7 g and purified water were added to a stainless-steel beaker to prepare a 5 wt% suspension. This suspension was heated to 50 °C or higher, and 585.3 g of a 10 wt% phosphoric acid solution (diluted from reagent grade, manufactured by FUJIFILM Wako Pure Chemical Corporation) was added dropwise. After the addition was completed, the mixture was left standing for 1 hour to synthesize HAP. The reaction solution was spray-dried at 200 °C and then sieved to obtain spherical hydroxyapatite (hereinafter referred to as spherical HAP). The obtained spherical HAP was confirmed to be hydroxyapatite (JCPDS: 9-432) by X-ray diffraction measurement. In addition, the pH, BET specific surface area, particle size (median diameter: d50), Ca / P molar ratio, full width at half maximum (FWHM), and oil absorption of the obtained spherical HAP are shown in Table 1, and Tt, Td, and haze value are shown in Table 2.

[0021] 〔Comparative Example 1〕(Hydrolysis method: manufacturing method of JP-A-2003-126687) 102.8 g of calcium hydrogen phosphate dihydrate (manufactured by Taihei Chemical Industry Co., Ltd.) and 29.9 g of calcium carbonate (reagent grade, manufactured by FUJIFILM Wako Pure Chemical Corporation) and purified water were added to a stainless-steel beaker to prepare a 10 wt% suspension. This suspension was heated and stirred at 90 °C and held for 4 hours to synthesize HAP. After the reaction solution was subjected to solid-liquid separation, it was dried at 150 °C and sieved to obtain plate-like HAP (plate-like HAP-1). The obtained plate-like HAP-1 was confirmed to be hydroxyapatite (JCPDS: 9-432) by X-ray diffraction measurement. In addition, the pH, BET specific surface area, particle size (median diameter: d50), Ca / P molar ratio, full width at half maximum (FWHM), and oil absorption of the obtained plate-like HAP-1 are shown in Table 1, and Tt, Td, and haze value are shown in Table 2.

[0022] 〔Comparative Example 2〕(Hydrolysis method: manufacturing method of JP-A-2003-126687) 102.8 g of calcium hydrogen phosphate dihydrate (manufactured by Taihei Chemical Industry Co., Ltd.) and 39.9 g of calcium carbonate (reagent special grade of Fujifilm Wako Pure Chemical Corporation) were added to a stainless steel beaker, and purified water was added to make a 10 wt% suspension. This suspension was heated and stirred at 90 °C and held for 4 hours to synthesize HAP. After the reaction solution was subjected to solid-liquid separation, it was dried at 150 °C and sieved to obtain plate-like HAP (plate-like HAP-2). The obtained plate-like HAP-2 was confirmed to be hydroxyapatite (JCPDS: 9-432) by X-ray diffraction measurement. In addition, the pH, BET specific surface area, particle size (median diameter: d50), Ca / P molar ratio, full width at half maximum (FWHM), oil absorption amount of the obtained plate-like HAP-2 are shown in Table 1, and Tt, Td, and haze value are shown in Table 2.

[0023] 〔Comparative Example 3〕(Wet method: manufacturing method of Patent No. 5654740) 73.7 g of calcium hydroxide (reagent special grade of Fujifilm Wako Pure Chemical Corporation) was added to a stainless steel beaker, and purified water was added to make a 10 wt% suspension. This suspension was heated to 50 °C or higher, and 195.1 g of 30 wt% phosphoric acid solution (diluted reagent special grade of Fujifilm Wako Pure Chemical Corporation) was dropped. After the dropping was completed, it was left for 1 hour to synthesize HAP. After the reaction solution was subjected to solid-liquid separation, it was dried at 150 °C and pulverized and sieved to obtain hydroxyapatite powder (powder HAP). The obtained powder HAP was confirmed to be hydroxyapatite (JCPDS: 9-432) by X-ray diffraction measurement. In addition, the pH, BET specific surface area, particle size (median diameter: d50), Ca / P molar ratio, full width at half maximum (FWHM), oil absorption amount of the obtained powder HAP are shown in Table 1, and Tt, Td, and haze value are shown in Table 2.

[0024] 〔Comparative Example 4〕(Hydrolysis method: manufacturing method of JP-A-2003-126687) 102.8 g of calcium hydrogen phosphate dihydrate (manufactured by Taihei Chemical Industry Co., Ltd.) and purified water were added to a stainless-steel beaker to prepare a 10 wt% aqueous suspension. A 50% aqueous solution of sodium hydroxide (reagent grade, manufactured by Fujifilm Wako Pure Chemical Corporation) was added dropwise to this suspension to adjust the pH to 7, and then the mixture was heated and stirred at 40 °C and held for 4 hours to synthesize HAP. After solid-liquid separation of this reaction solution, it was dried at 150 °C and subjected to sieving to obtain plate-like HAP (plate-like HAP-3). The obtained plate-like HAP-3 was confirmed to be hydroxyapatite (JCPDS: 9-432) by X-ray diffraction measurement. In addition, the pH, BET specific surface area, particle size (median diameter: d50), Ca / P molar ratio, full width at half maximum (FWHM), and oil absorption of the obtained plate-like HAP-3 are shown in Table 1, and Tt, Td, and haze value are shown in Table 2.

[0025] For Comparative Examples 5 to 10, the following commercially available products were used, and their pH, BET specific surface area, particle size (median diameter: d50), Ca / P molar ratio, full width at half maximum (FWHM), and oil absorption are shown in Table 1, and Tt, Td, and haze value are shown in Table 2. Comparative Example 5: Titanium oxide (fine particle titanium oxide MT-500B, manufactured by Teika Co., Ltd.) TIFF2025109970000005.tif13152 Comparative Example 7: Talc (talc JA-46R, manufactured by Asada Flour Milling Co., Ltd.) Comparative Example 8: Silica (Sunsphere H-121, manufactured by AGC SI Tech Co., Ltd.) Comparative Example 9: Sericite (sericite FSE, manufactured by Sanshin Kogyo Co., Ltd.) Comparative Example 10: Mica (mica M-302, manufactured by Miyoshi Kasei Co., Ltd.)

[0026]

Table 1

[0027]

Table 2

[0028] From the above results, the hydroxyapatite of the present invention has a high total transmittance of 89.30% and, in addition, a high haze value of 67.03%, so it has an excellent soft focus effect. When formulated in makeup cosmetics (including hair cosmetics) such as foundations and used on the skin, a natural finish with transparency can be expected without overly concealing the skin and without white streaks.

Industrial Applicability

[0029] The hydroxyapatite of the present invention can be formulated in makeup cosmetics (lipsticks, eyeshadows, foundations, nail enamels, mascaras, hair treatments, hair liquids, setting lotions, etc.) including hair cosmetics for pharmaceuticals, quasi-drugs, cosmetics, etc., and can be provided in dosage forms such as oily solid, oily liquid, solid, cream, paste, emulsion, lotion, powder, powder solid, etc. with a high soft focus effect.

Claims

1. Spherical hydroxyapatite having a Ca / P molar ratio of 1.4 to 1.8 and having a soft focus effect.

2. Spherical hydroxyapatite having a soft focus effect, wherein the half-value width of the X-ray diffraction analysis result with d = 2.814 Å described in Claim 1 is 0.5° or less.

3. Spherical hydroxyapatite having a soft focus effect with a BET specific surface area of 60 m ２ / g or less as described in any one of claims 1 to 2.

4. Spherical hydroxyapatite having a soft focus effect, wherein the particle size (median diameter: d50) described in any one of Claims 1 to 3 is 10 μm or less.

5. Spherical hydroxyapatite having a soft focus effect, wherein the pH of a 10 wt% suspension of the hydroxyapatite described in any one of Claims 1 to 4 is 6 to 12.

6. Spherical hydroxyapatite having a soft focus effect, wherein the total transmittance described in any one of Claims 1 to 5 is 80% or more and the haze value is 35% or more.

7. Spherical hydroxyapatite having a soft focus effect, wherein the oil absorption amount described in any one of Claims 1 to 6 is 250 mL / 100 g or less.

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