JP2861806B2 - Metal oxide fine particle dispersed flake glass and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flake-like glass in which metal oxide fine particles are dispersed, in particular, for example, an ultraviolet shielding agent having high ultraviolet shielding ability and high transparency to visible light, and a smooth surface suitable for cosmetics. TECHNICAL FIELD The present invention relates to a metal oxide fine particle-dispersed flake glass having high properties, a cosmetic using the same, and a method for producing a metal oxide fine particle-dispersed flake glass having a smooth surface using a solution containing an organic metal compound as a starting material.

[0002]

2. Description of the Prior Art Flake glass is currently used for plastic fillers, corrosion resistant linings or paints. Such flaked glass is mainly composed of soda-lime silicate glass, and has a thickness of about 4 microns. The molten glass is expanded like a balloon, quenched,
It is manufactured by grinding. However, if various substances are mixed into the glass flakes to give new performances (for example, high heat resistance, ultraviolet shielding properties, electromagnetic shielding properties, etc.), 1) the added substances due to high temperature melting state It is practically difficult to efficiently produce high-quality products because there are limitations on the type and amount of the compound, and 2) steps such as heat treatment are required for crystallization, phase separation, and the like. Was.

As another production method, a solution containing an organometallic compound capable of hydrolysis and polycondensation and in which fine particles are dispersed is applied on a substrate, preferably a substrate having a smooth surface, and dried. There is known a method for producing a glass flake having fine particles dispersed therein, which is separated from a substrate by sintering.
(JP-A-63-126818, JP-A-1-14382)
The metal oxide fine particle dispersed flake glass produced using titanium oxide or the like as the fine particles is added and blended in paints, plastic films, plastic molded products, cosmetic base materials, and the like. It is used as a wetting inhibitor, surface modifier, and ultraviolet shielding agent.

[0004]

The glass flakes dispersed in fine particles such as titanium oxide, zinc oxide and cerium oxide produced according to this method do not agglomerate with time and have good spreadability, but they are good for metal oxides. When the fine particles easily form an aggregate from the beginning, and particularly when the thickness of the flake glass required is small, the diameter of the aggregate increases and the aggregate tends to protrude from the surface of the flake glass inevitably. And the following various problems occur. (1) The smoothness, glossiness, and slipperiness of the surface of the flaky glass, which are inherent characteristics, are lost, which is not preferable in applications that value decorativeness and the like. (2) In the case where titanium oxide having an ultraviolet shielding effect is used as the metal oxide fine particles, the titanium oxide exposed from the surface of the flake glass degrades a surrounding resin material or skin (in the case of cosmetics) due to its photocatalytic action. There is a risk of being hurt. (3) When metal oxide fine particles are used for shielding or absorbing light such as visible light, ultraviolet light, infrared light, etc., they are not uniformly dispersed and distributed. It is not economical to use oxide fine particles. (4) In some cases, the flake glass is required to have transparency and transparency, but the transparency and transparency are likely to be lost due to generation of aggregates of metal oxide fine particles.

SUMMARY OF THE INVENTION In view of the above prior art, the present invention has been difficult to produce in the past. Metal oxide fine particles are uniformly dispersed and distributed, and have high surface smoothness, high transparency, and high ultraviolet shielding ability. It is an object of the present invention to provide a flake-like glass in which fine particles of an object are dispersed, and a method capable of easily and efficiently producing the glass.

[0006]

Means for Solving the Problems In order to solve this problem,
The present inventors have produced simpler and more efficient high-quality fine particle-dispersed glass flakes by using metal oxide fine particles having a hydroxyl group on the surface as metal oxide fine particles to be added to a solution containing an organometallic compound and water. I found what I could do.

That is, according to the present invention, there is provided a flake glass in which metal oxide fine particles are dispersed, wherein the metal oxide fine particles are derived from colloidal particles having a hydroxyl group and have a particle diameter of 1 to 300 nm .
And the content thereof is substantially 1 in the form of single particles without agglomeration of the titanium oxide fine particles in the glass .
60% by weight, and the wavelength is 400 to
The transmittance for 800 nm visible light is
Te is 80% or more, the surface is smooth metal oxide particulate dispersion glass flakes. The present invention relates to (1), respectively hydrous metal oxides, metal oxides having a hydroxyl group in the metal hydroxide or surface, of the colloidal particles (as oxide) 0.3 to 20 wt% (2) Hydrolysis and 5 to 50% by weight of an organometallic compound capable of polycondensation (3) 10 to 50% by weight of an alcohol (4) 0.001 to 5% by weight of an acid catalyst (5) Water The remainder except that the organometallic compound (2) and an alcohol (3)
A solution consisting of a total of 90% by weight or less, having a smooth surface
Apply on the substrate, dry this to peel off the coating film,
A metal oxide fine particle dispersion frame characterized by sintering.
This is a method for producing a glass-like glass.

The colloid used in the present invention may have a hydroxyl group on the particle surface, and preferably has a hydroxyl group in the composition of the colloid. Specifically, a hydrated metal oxide (MxOy (OH) z, for example, TiO (OH) ₂ ), a metal hydroxide (Mx (OH) y, for example, Ti (OH) ₄ ), or a particle having a hydroxyl group on its surface. Metal oxide particles are used as a single component or two or more components. However, here
M is various metal atoms, O is oxygen atom, H is hydrogen atom, x, y, z
Indicates a natural number. M, Ti, Sn, Si, Fe, Zr, Al, Z
n, Ce and the like are preferably used. Such a colloid is excellent in monodispersibility in a liquid having a high water content, and is uniformly dispersed in a solution containing the organometallic compound and water.
Hydrous metal oxide (MxOy (OH) z, for example TiO (OH) ₂ )
And metal hydroxides (Mx (OH) y, such as Ti (OH) ₄ )
Is generally commercially available, and metal oxide particles having a hydroxyl group on the surface of the particles are formed of a metal compound such as nitric acid
An aqueous iron solution is added to boiling water, heated, and then cured at about 30 ° C. for several hours to obtain colloidal particles of α-Fe 2 O 3 (hematite) having a hydroxyl group on the surface.

The dispersoid composition of the colloid and the fine particle composition at the time of forming the flake glass after sintering are not necessarily the same. In many cases, depending on the sintering temperature, the hydrated metal oxide An object or a metal hydroxide changes into a metal oxide.

[0010] The particle size of the colloid is preferably from 1 nm to 1000 nm, more preferably from 1 nm to 500 nm. If the particle size is smaller than 1 nm, the particle size at the time of forming the flake glass may not be large, which is not preferable. On the other hand, if the particle size is larger than 1000 nm, it is difficult to stably disperse the solution in a solution containing an organic metal compound and water, which is not preferable. When a colloid having a particle diameter larger than 500 nm is used, the surface of the flakes may become large and irregular at the time when the flake-like glass is formed, or the transparency may be impaired. Since these are sometimes not good, the use of colloids larger than 500 nm is less preferred. Especially when the fine particles are titanium oxide fine particles, the diameter is 1 nm
Above, it is 300 nm or less. If it is smaller than 1 nm, the light scattering effect of the fine particles is reduced, and the ultraviolet shielding effect is reduced, which is not preferable. On the other hand, if it is larger than 300 nm, transparency to visible light is impaired, which is also not preferable.

The colloid solvent is not particularly limited as long as the colloid particles are substantially stably dispersed.
A simple substance or a mixture of water, methanol, ethanol, propanol and the like are preferable, and water is more preferable. These water and lower alcohol are good because they can be easily mixed with a solution containing the organometallic compound and water, and can be easily removed by heat treatment at the time of flake formation and after flake formation.
Among them, water is most preferable in the flake glass production environment.

The content of the above colloidal particles is 0.1% by weight or more and 80% by weight or less when the flake glass is obtained. If it is less than 0.1% by weight, the effect of adding fine particles is not substantially exhibited, and if it is more than 80% by weight, the glass phase becomes discontinuous and the flake glass becomes brittle, which is not preferable. Practically preferably 1 wt% or more, 60
It is good that it is below weight%. In particular, the content of the titanium oxide fine particles is preferably 1% by weight or more and 60% by weight or less. If the content is less than 1% by weight, the effect of blocking ultraviolet rays is not sufficient, which is not preferable. If the content is more than 60% by weight, the glass phase becomes discontinuous, the flake-like glass tends to be brittle, and the transparency of visible light decreases, which is not preferable.

When the above-mentioned colloid is added to a solution containing the above-mentioned organometallic compound capable of hydrolysis and polycondensation and water, a dispersing aid may be added. Dispersion aids are not particularly limited, and commonly used additives, for example, electrolytes such as sodium phosphate, sodium hexametaphosphate, potassium pyrophosphate, aluminum chloride, iron chloride, various surfactants, various organic polymers, and silane A coupling agent, a titanium coupling agent or the like is used, and the amount of the coupling agent is usually 0.05 to 5 with respect to the solution containing the organometallic compound and water.
% By weight.

By using the colloid as a source of fine particles having a hydroxyl group on at least the surface, the colloid is uniformly dispersed in a solution containing the organometallic compound and water. Those having very high fine particle dispersibility and excellent properties can be easily produced.

The organic metal compound used in the present invention may be basically any compound as long as it undergoes hydrolysis and dehydration condensation, but a metal alkoxide having an alkoxyl group is preferred. Specifically, methoxide such as Si, Ti, Al, and Zr, ethoxide, propoxide, butoxide, and the like are used alone or as a mixture. Usually, an organic compound of a metal different from the kind of metal of the metal oxide of the fine particles is used.

The solvent of the solution containing the organometallic compound is
Any substance can be basically used as long as the organic metal compound is substantially dissolved, but alcohols such as methanol, ethanol, propanol, and butanol are most preferable, and the organic metal compound is contained at a concentration of 1 to 30% by weight.

Water is required for the hydrolysis of the organometallic compound. This may be acidic, neutral or basic, but it is preferable to use water acidified with hydrochloric acid, nitric acid, sulfuric acid or the like in order to promote hydrolysis. The amount of the acid added is not particularly limited, but may be 0.
001 ~ 2 is good. If the amount of the added acid is less than 0.001 in molar ratio, the promotion of the hydrolysis of the organometallic compound is not sufficient, and if the amount is more than 2, the effect of promoting the hydrolysis is no longer improved and the acid is excessive. Is not preferred.

The added water is also necessary for stabilizing the dispersion of the colloid. The added amount of water is preferably 10% by weight or more and 80% by weight or less of the solution. However, the water content here is the sum of the amount of water contained in the colloid and the newly added water. If the amount of water added is less than 10% by weight of the solution, the colloid tends to be unable to stably exist, which is not preferable. On the other hand, if the amount of water added is more than 80% by weight of the solution, the concentration in terms of solids in the solution is too low, and the yield of flakes is low.

In addition, an organic thickener or the like may be added to change the properties of the solution. However, if this addition amount is large, carbonization may occur in the final stage of heating, so the addition amount should be kept at 10% by weight or less.

The substrate used in the present invention is made of a material such as metal, glass or plastic and has a smooth surface. On such a substrate, the above colloid, acid catalyst, water,
A colloid of an organometallic compound and a liquid containing a solvent of the organometallic compound, preferably a solution having the following composition: (1) a hydrated metal oxide, a metal hydroxide, or a metal oxide having a hydroxyl group on its surface, respectively Particles (in terms of oxide) 0.3 to 20% by weight (2) Organometallic compound capable of hydrolysis and polycondensation 5 to 50% by weight (3) Alcohol 10 to 50% by weight (4) Acid catalyst 0.001 5% by weight (5) Apply the rest of water to form a thin film of 0.06 to 50 microns. When this film dries, it shrinks to a fraction of the film thickness, from 0.01 to 5
Although the film has a thickness of μm, since the substrate does not shrink, the film is cracked and formed into a flake shape. In order to easily cause separation between the substrate and the film, it is preferable to use a material such as stainless steel as a substrate to be coated in a state where interaction such as strong bonding between the substrate and the film is small.

As a technique for forming a film on the substrate surface, a known technique may be used. For example, the above-mentioned colloid, water,
A method of immersing the substrate in a liquid containing an organometallic compound and then lifting the substrate, a method of dropping the liquid on the substrate and rotating the substrate at a high speed, and a method of spraying the liquid on the substrate are used.

The thickness of the glass flakes produced in the present invention varies depending on the solution or film forming conditions, but is generally between 5 microns and 0.05 microns. If the thickness is more than 5 microns, the difference in drying speed between the free surface after film formation and the vicinity of the substrate becomes too large, and peeling between the films in a direction parallel to the substrate occurs. Conversely, if the thickness is less than 0.05 micron, the adhesion between the substrate and the film becomes too large, and the film does not peel off from the substrate.

With respect to sintering, the method is not particularly limited. The sintering temperature and time are preferably at least as high as possible to ensure the transition of the matrix from gel to glass, and it is preferable to heat the flake gel after exfoliation.
Heat at ~ 1200 ° C for 10 minutes to 5 hours. Depending on the purpose of use, sintering after drying may not be required.
This sintering increases the mechanical strength of the flaked glass, but further reduces its thickness and dimensions by about 3 to 10%.

The metal oxide fine particle-dispersed highly transparent flake glass using titanium oxide having a hydroxyl group on the surface as the metal oxide fine particles has a wavelength of 400 to 400 when dispersed in a medium having a refractive index in the range of 1.3 to 1.6. The transmittance for 800 nm visible light is 80% or more over the entire region. However, the transmittance here is in accordance with the method of JISK0115, and the transmittance of the medium alone is
It is a value measured by a spectrophotometer as 100%.

In the cosmetic of the present invention using the flaky glass dispersed with metal oxide (particularly titanium oxide) fine particles having a smooth surface, in addition to the above-mentioned flaky glass dispersed with titanium oxide fine particles, the flaky glass may be used as required. It does not matter what kind of pigment is used. For example, titanium oxide, zinc oxide, zirconium oxide, yellow iron oxide, black iron oxide, red iron oxide, ultramarine, navy blue, chromium oxide, inorganic pigments such as chromium hydroxide, titanium mica, pearlescent pigments such as bismuth oxychloride, tar Dyes, natural dyes, silica beads, nylon,
Examples include powders of plastic beads such as acrylic, talc, kaolin, mica, sericite, other mica, magnesium carbonate, calcium carbonate, aluminum silicate, magnesium silicate, clays and the like.

The amount of the flaky glass in which the titanium oxide fine particles are dispersed varies depending on the type of the intended cosmetic, but is used in the range of 1 to 80% by weight based on the solid components such as pigments. It is preferably in the range of ~ 50% by weight.
If the content is less than this, the ultraviolet shielding effect is not remarkably exhibited, and conversely, even if more flake glass is added than the upper limit, the ultraviolet shielding effect does not increase, other pigment components decrease, and the color tone is adjusted. Or it is difficult to increase the adhesion to the skin.

Further, in order to improve the dispersibility of the titanium oxide fine particle dispersed flake glass used in the present invention in cosmetics and to improve the feel, the flake glass is subjected to a surface treatment to be modified. You can do nothing at all. For example, in addition to methyl hydrogen polysiloxane, reactive alkyl polysiloxane, metal soap, hydrogenated lecithin, acyl amino acid, metal salt selected from aluminum, magnesium, calcium, titanium, zinc, zirconium, iron of acylated collagen, etc. When surface treatment is performed with a so-called hydrophobizing agent, the surface of the flaked glass changes from hydrophilic to hydrophobic, so that the familiarity with the oil agent added at the time of preparation of the cosmetic is improved, and the cosmetic has a good feel. .

[0028]

Examples are shown below. Example-1 Commercially available hydrous titanium oxide colloid TiO (OH) ₂ (trade name: titania sol CS-N, manufactured by Ishihara Sangyo Co., Ltd., content in terms of titanium dioxide: about 30% by weight, particle diameter: 30 to 60 nm, water dispersion) 6
00 ml, 9500 ml of 0.2 N nitric acid, 20 g of sodium hexametaphosphate as a dispersing aid, silicon tetramethoxide
5400 ml, 3380 ml of ethanol and 3380 ml of 2-propanol were mixed and cured at 35 ° C. for about 70 hours to obtain a coating solution. A 0.5 mm-thick stainless steel plate whose surface was polished and smoothed was immersed in this liquid, and pulled up at a speed of about 30 cm / min. (The thickness of the dip coating is about 10 μm.) This is dried at 100 ° C., the gel film is peeled off, and sintered at 1000 ° C. for 3 hours.
A sintered film of 00 μm was obtained. When this sintered film was examined by an x-ray diffraction method, only anatase type titanium dioxide was detected, and the matrix was in a silica glass state. As a result of chemical analysis, the content of titanium dioxide was about 9.5% by weight. When the flakes were observed with a transmission electron microscope, the diameter was 30 to
It was observed that titanium dioxide fine particles of 60 nm were located in an average dispersed state in the silica glass matrix.

The sintered flakes are pulverized by a jet mill,
The particles were classified to have an average particle size of about 10 μm. When the flakes were observed with a scanning electron microscope, the surface of the flakes was very smooth as shown in FIG.
It was about 0.6 μm (600 nm).

A coating obtained by mixing and dispersing about 10% by weight of the flakes in a vinyl resin (having a refractive index of about 1.5 after curing) is applied on a substrate and dried to form a film having a thickness of about 0.15 mm. When the transmittance was measured with a photometer, the wavelength
A flake glass that has a visible light transmittance of 400 to 800 nm of 95% or more over the entire area and an ultraviolet transmittance of 350 nm or less of 5% or less, and is transparent to visible light and effectively blocks ultraviolet light. It was confirmed that there was.

Example-2 The same hydrous titanium oxide colloid as used in Example 1
5520 ml of TiO (OH) ₂ (titania sol CS-N), 9900 ml of 2.3N nitric acid, 4300 ml of silicon tetramethoxide, 1100 ml of ethanol and 1100 ml of 2-propanol were mixed, and the mixture was mixed at 50 ° C.
For about 40 hours to obtain a coating solution. Using this coating solution, sintered flakes were obtained in the same manner as in Example 1. When this flake was examined by x-ray diffraction, only anatase-type titanium dioxide was detected. As a result of chemical analysis, the content of titanium dioxide in the sintered flake was about 55% by weight. Observation of the flakes with a transmission electron microscope showed that titanium dioxide fine particles having a size of 30 to 80 nm were monodispersed in a silica glass matrix. When the flakes were observed with a scanning electron microscope, the surface was very smooth, and the thickness of the flakes was about 0.8 μm (800 nm).

Example 3 2N hydrochloric acid was added dropwise to a 0.1 mol / l solution of titanium isobutoxide in anhydrous ethanol, and the mixture was aged and aged to obtain a titanium hydroxide sol. This was concentrated by ultrafiltration to obtain a titanium hydroxide colloid having a content of about 10% by weight in terms of titanium dioxide and a particle diameter of 30 to 80 nm. 2500 ml of this titanium hydroxide colloid, 0.
02 8000 ml of specified nitric acid, 5400 m of silicon tetramethoxide
l, 2350 ml of ethanol and 3850 ml of 2-propanol were mixed and cured at 40 ° C. for about 55 hours to obtain a coating solution.

Using this coating solution, sintered flakes were obtained in the same manner as in Example 1. When this flake was examined by an x-ray diffraction method, only anatase-type titanium dioxide was detected, and the matrix was in a glassy state. As a result of chemical analysis, the content of titanium dioxide was about 9.5% by weight.
Met. Observation of the flakes with a transmission electron microscope showed that titanium dioxide fine particles having a diameter of 30 to 80 nm were monodispersed in a silica glass matrix. When the flakes were observed with a scanning electron microscope, the surface was very smooth and the thickness was about 0.6 microns.
(600 nm).

Example 4 5000 ml of a 0.35 mol / l aqueous solution of iron nitrate was heated to boiling, and a 2N aqueous solution of potassium hydroxide was added dropwise.
The pH was set to 7. After returning to room temperature, the resulting red precipitate was separated, washed with water, and cured in an autoclave at 150 ° C. for 10 hours. After washing with water having a pH of 9 and ion-exchanged water and diluting with water containing nitric acid having a pH of 2, about 20% by weight
Hematite (α-Fe ₂ O ₃ ) colloid was obtained. When the colloid particle diameter was measured by the dynamic light scattering method, the average particle diameter was about 110 nm.

2000 ml of this hematite colloid, 2200 ml of silicon tetramethoxide, 1000 ethanol
and 2-propanol (1000 ml) at 40 ° C.
After curing for 0 hour, a coating solution was obtained. A 0.5 mm-thick stainless steel plate whose surface was polished and smoothed was immersed in this solution, and pulled up at a speed of 30 cm / min. This was dried at 150 ° C., the gel film on the plate surface was peeled off, and sintered at 950 ° C. for 1 hour. After sintering, when examined by X-ray diffraction, only a sharp peak of hematite was detected, and the matrix was in a glassy state. As a result of chemical analysis, the content of hematite was about 30% by weight. Observation of the flakes with a transmission electron microscope revealed that the flakes were about 80 to 140 nm.
Large hematite fine particles were observed to be monodispersed in the silica glass matrix. When the flakes were observed with a scanning electron microscope, the surface was very smooth and the thickness was about 0.6 μm. The sintered flakes are pulverized and classified with a jet mill to an average particle size of about 10 microns, and a transparent vinyl resin (having a refractive index of about 1.
5) A resin film having a thickness of about 0.15 mm dispersed in about 5% by weight and measured for transmittance with a spectrophotometer. As a result, the visible light transmittance at a wavelength of 700 to 800 nm is 85% or more over the entire wavelength range. It was confirmed that it was a reddish-brown flaky glass having a transmittance of 5% or less for ultraviolet rays having a wavelength of 350 nm or less, having high transparency to visible light, and effectively shielding ultraviolet rays.

Example-5 600 ml of a 1N aqueous ferric nitrate solution in about 3000 ml of boiling water
Was added, heated and boiled for about 20 minutes. Continue at 60 ° C
Cured for 5 hours at 30 ° C. for 30 hours and diluted 2-fold with water to obtain reddish brown colloid. Analysis of the colloid composition using techniques such as X-ray diffraction showed that α-Fe2O3 (Hematite)
And FeO (OH) (containing iron hydroxide) and Fe (OH) 3 (iron hydroxide).
When the particle diameter was measured by the dynamic light scattering method, the particle diameter was 50 to 120 nm.

8600 ml of this colloid, 4900 ml of silicon tetramethoxide, 3000 ml of ethanol and 3000 of 2-propanol
The mixture was mixed and cured at 35 ° C. for about 70 hours to obtain a coating solution. A 0.5 mm-thick stainless steel plate whose surface was polished and smoothed was immersed in this liquid, and pulled up at a speed of 30 cm / min.
This is dried at 150 ° C, and the gel film on the plate surface is peeled off.
Sintered at 0 ° C. for 5 hours. After sintering, when examined by X-ray diffraction, only a sharp peak of α-Fe2O3 (Hematite) was detected, and the matrix was in a glassy state.
As a result of chemical analysis, the content of hematite was about 6.3% by weight.
Met. Observation of the flakes with a transmission electron microscope showed that hematite fine particles having a size of about 40 to 120 nm were monodispersed in a silica glass matrix.
Observation of the flakes with a scanning electron microscope showed that the surface was very smooth and about 0.6 microns thick.

Example -6 An aqueous 15% ammonia solution was slowly added to an aqueous cerium chloride solution of 0.5% by weight in terms of cerium oxide until the pH reached 9, to obtain a precipitated gel of hydrous cerium oxide. The sedimented gel was separated by a centrifugal separator, dehydrated, and washed, and 500 g of the sedimented gel was added with 600 g of 35% hydrogen peroxide solution and 130 g of water, and then heated at 80 ° C
To obtain a transparent sol. This sol was diluted with water so as to be 0.2% by weight in terms of cerium oxide, and then heat-cured at 95 ° C. in an autoclave for 50 hours to obtain a mixed colloid of cerium oxide and hydrated cerium oxide. The colloid was concentrated by a vacuum evaporation method until the concentration in terms of cerium oxide became 10% by weight. The obtained colloid had a particle size of 10 to 30 nm.

2500 ml of this colloid, 8000 of 0.05 N nitric acid
ml, silicon tetramethoxide 5400ml, ethanol 3500
The mixture was mixed with 3500 ml of 2-propanol and cured at 40 ° C. for about 55 hours to obtain a coating solution.

Using this coating solution, sintered flakes were obtained in the same manner as in Example 1. When this flake was examined by X-ray diffraction, only cerium oxide was detected, and the matrix was in a glassy state. As a result of chemical analysis, the content of cerium oxide was about 9.5% by weight.
When the flakes were observed with a transmission electron microscope, 10 to 40
It was observed that cerium oxide fine particles having a size of nm were monodispersed in a silica glass matrix. When the flakes were observed with a scanning electron microscope, the surface was very smooth and the thickness was about 0.4 μm.

When the above sol was heated and cured at 95 ° C. for 500 hours instead of heating at 95 ° C. for 50 hours, a colloid of cerium oxide alone was obtained. Then, when the same treatment as above was performed, cerium oxide fine particles of 10 to 40 nm in size were obtained.
Monodispersion was observed in the silica glass matrix. When the flakes were observed with a scanning electron microscope, the surface was very smooth and the thickness was about 0.4 μm.

Comparative Example-1 Commercially available fine particle titanium oxide (trade name: MT-500B, Teica
(Primary particle size: 20 to 50 nm, rutile type) was dispersed in water to a concentration of 10% by weight using a commercially available paint shaker. 2500 ml of this suspension, 8000 of 0.24 N nitric acid
ml, silicon tetramethoxide 5400ml, ethanol 3380
The mixture was mixed with 3380 ml of 2-propanol and cured at 35 ° C. for about 70 hours to obtain a coating solution. The concentration of titanium dioxide in this coating solution is almost the same as the concentration of titanium dioxide in the coating solution of Example-1.

Using this coating solution, sintered flakes were obtained in the same manner as in Example 1. As a result of chemical analysis, the content of titanium dioxide was about 4.8% by weight. This is considered to be because the titanium dioxide fine particles settled in the coating solution. When the flakes were observed with a transmission electron microscope,
As shown in FIG. 3, the number of fine particles monodispersed in the silica glass matrix was small, and it was observed that 10,000 to tens of thousands of fine particles aggregated to form an aggregate having a diameter of about several microns. . When the flakes were observed with a scanning electron microscope, irregularities of titanium dioxide aggregates were observed on the surface, and the smoothness was poor. The sintered flake thickness is about 0.6
Micron. This unevenness of the surface is a natural consequence of the fact that the diameter (several microns) of the aggregate of the titanium dioxide fine particles exceeds the thickness of the flakes of the silica glass matrix (about 0.6 μm).

The sintered flakes are pulverized by a jet mill,
Classify to an average particle size of about 10 microns, disperse about 10% by weight in a transparent vinyl resin (refractive index after curing is about 1.5), and use a spectrophotometer as a resin film about 0.15 mm thick. When the transmittance was measured, the visible light transmittance at a wavelength of 400 to 800 nm was 40 to 50%, and the ultraviolet transmittance at a wavelength of 350 nm or less was 2% or less. That is, it was confirmed that the flake glass had high ultraviolet shielding performance, but had considerably reduced transparency to visible light. It is considered that such low visible light transparency is due to scattering and absorption of visible light by titanium dioxide aggregates protruding inside and on the surface of the sintered flake. Comparative Example-2 Commercially available fine iron oxide particles (trade name: Nanotite, Showa Denko
(Primary particle size: 40-60 nm, Hematite) was dispersed in water to a concentration of 3.2% by weight using a commercially available paint shaker. 4300 ml of this suspension, 4300 m of 0.3 N nitric acid
l, silicon tetramethoxide 4900ml, ethanol 3000
The mixture was mixed with 3,000 ml of 2-propanol and cured at 35 ° C. for about 70 hours to obtain a coating solution. The concentration of iron oxide in this coating solution was almost the same as the concentration in terms of iron oxide in the coating solution of Example-3.

Using this coating solution, sintered flakes were obtained in the same manner as in Example 3. As a result of chemical analysis, the content of hematite was about 2.1% by weight. This is considered to be because iron oxide fine particles settled in the coating solution. Observation of the flakes with a transmission electron microscope revealed that there were few fine particles monodispersed in the silica glass matrix,
It was observed that aggregates of about several microns were formed. When the flakes were observed with a scanning electron microscope, irregularities of the iron oxide fine particle aggregates were observed on the surface, and the smoothness was poor. The thickness was about 0.6 microns.

Example-6 and Comparative Example-3 A powder foundation was prepared with the following composition. Component-1 Amount (% by weight) of the present invention produced in Example-1 Flake glass 5.0 Talc 74.7 Mica 9.1 Titanium oxide (primary particle size 200 to 250 nm) 3.8 Fine particle titanium oxide (primary particle size 30 to 50 nm) 1.9 Magnesium stearate 2.9 Petals 0.5 Yellow iron oxide 0.8 Black iron oxide 0.1 Silk powder 0.5

Component-2 Compounding amount (% by weight) ----------------------------------------------------------- Squalane 0.5 Sorbitan sesquioleate 0.1 Ingredient-3 Compounding amount (% by weight)------------------------------Fragrance 0.1

Using a Henschel mixer, add Component-1 to 5
Stirred for minutes. In addition, the components that are uniformly melted at 70 ° C
While dropwise adding 2, stirring and mixing were performed. In addition, component-3
Was added, and the mixture was stirred and mixed for 1 minute, and pulverized with an atomizer to obtain a product-1 (Example-6). Product-2 (Comparative Example-3) was obtained in the same manner as described above, except that the flake glass of the present invention in Component-1 was not added.

0.22 g of each of Product-1 and Product-2 was collected and applied uniformly and adjacently to the skin at the center of the back of the five subjects, 4 cm x 5 cm, and from 11 am in Izu in August. After being exposed to direct sunlight for 30 minutes to 3 hours between 2 pm, the degree of sunburn was observed.

Table 1 shows the results. Five
The average value of the degree of sunburn of a human subject was determined according to the following classification: 1; hardly sunburned; 2; sunburn was found; 3; sunburned slightly red; 4; After a lapse of 30 minutes from the peeling of the powder, almost no difference was visually observed, but after 1 hour, a remarkable difference was observed, and the powder containing the flaky glass dispersed with titanium oxide fine particles of the present invention ( The sunburn of the skin to which Product-1 and Example-6) were applied was compared to the case where the powder (Product-2 and Comparative Example-3) which did not contain the flaky glass was applied.
It had been greatly reduced.

[0051]

Table 1 Table 1 ================================= Powder of the present invention (product-1) ) Comparative powder (product-2) (Example-6) (Comparative example-3) --------------------------------------------------------------------------- −−−−−− 30 minutes later 11 1 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 hour later 13 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− After 2 hours 15 −−−−−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−− 3 hours later 25 ======================= ============

The above two products were given to 20 female panelists 10 times.
Table 2 shows the results of the average points of the sensory tests evaluated using a 5-point scale with the highest score being 5 points and the lowest score being 1 point.

[0053]

[Table 2] Table 2 =============================== Item Powder of the present invention (product-1) Comparative powder (product-2) (Example-6) (Comparative example-3) --------------------------------------------------------------------------- −−− Noby 4.8 1.6 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− With 4.63.8 − −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− Transparent 4.8 3.5 −−−−−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−− Gloss 4.4 2.8 −−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− Color sense 4.3 3.2 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− -Performance Sustainability 4.8 2.0 ============== ===================

As described above, it was confirmed that the cosmetic of the present invention had good spreadability (adhesiveness), good transparency and glossiness, excellent color development, and did not easily fade.

Example-7 Commercially available hydrous titanium oxide colloid (trade name: titania sol)
CS-N, manufactured by Ishihara Sangyo Co., Ltd., titanium dioxide equivalent content: about 30% by weight, particle size: 30-60 nm, water dispersion) 175 ml, 0.01N nitric acid 6430 ml, silicon tetramethoxide 5390 ml, ethanol 5000 ml, 2-propanol Mix 5000 ml, add 3 g of sodium hexametaphosphate while performing ultrasonic irradiation,
After curing at 35 ° C. for about 70 hours, a coating solution was obtained.

Using this coating solution, sintered flakes were obtained in the same manner as in Example 1. As a result of chemical analysis, the content of titanium dioxide was about 3% by weight. Observation of the flakes with a transmission electron microscope showed that titanium dioxide fine particles having a size of 10 to 50 nm were monodispersed in a silica glass matrix. Observation of the flakes with a scanning electron microscope revealed that the surface was very smooth and about 0.5 micron thick.

The sintered flakes are pulverized and classified by a jet mill to have an average particle diameter of about 10 μm, and dispersed in a vinyl resin (having a refractive index of about 1.5 after curing) of about 20% by weight.
When the transmittance of a thick film was measured with a spectrophotometer, the visible light transmittance at a wavelength of 400 to 800 nm was 95% or more over the entire region, and the ultraviolet transmittance at a wavelength of 330 nm or less was 5% or less. It was confirmed that the flake glass was transparent to visible light and effectively blocked ultraviolet rays.

Comparative Example-4 Commercially available fine particle titanium oxide (trade name: MT-500B, Teica
Using a commercially available paint shaker, a primary particle diameter of 20 to 50 nm (rutile type) is dispersed in a vinyl resin (refractive index after curing is about 1.5) by about 0.6% by weight, and about 0.3 mm When the transmittance of the thick film was measured by a spectrophotometer, the visible light transmittance at a wavelength of 400 to 800 nm was about 90%, and the ultraviolet transmittance at a wavelength of 330 nm or less was about 70%. In a film of the same thickness dispersed about 6% by weight in a vinyl resin,
The visible light transmittance at a wavelength of 400 to 800 nm was 45 to 55%, and the ultraviolet transmittance at a wavelength of 350 nm or less was 5% or less.

That is, it is difficult to uniformly disperse the fine particle titanium oxide, and if added in a small amount, the ultraviolet shielding is not sufficient. When added in a large amount, the ability to block ultraviolet rays is improved, but hiding properties due to particle aggregation appear, and the transparency to visible light is reduced.

[0060]

According to the present invention, a monodispersed state of fine particles can be easily obtained by using a solution containing a colloid having a hydroxyl group on the particle surface, water and an organometallic compound, and the surface has a high smoothness. Quality fine particle dispersed flake glass,
And a titanium oxide fine particle dispersed flake glass as an ultraviolet ray shielding agent is obtained as a ultraviolet ray shielding agent having a high ultraviolet ray shielding ability and a high transparency to visible light.
Since the flaky glass in which titanium oxide fine particles are dispersed has high transparency in visible light and does not change with time, a stable product having good coloring properties can be obtained. In addition, since the flaky glass in which titanium oxide fine particles are dispersed does not agglomerate with each other and exhibits good sliding properties, a product having good extensibility (spreadability) and excellent feeling in use can be obtained. In addition, it is possible to more easily and efficiently produce these flake-like glass particles.

[Brief description of the drawings]

FIG. 1 is an electron micrograph (high magnification) of a flake glass in which metal oxide fine particles are dispersed according to the present invention.

FIG. 2 is another electron micrograph of the flake glass in which the metal oxide fine particles are dispersed according to the present invention.

FIG. 3 is an electron micrograph of flake glass in which metal oxide fine particles are dispersed for comparison.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C03C 12/00 C03C 12/00 (56) References JP-A-6-116520 (JP, A) (58) Fields investigated (Int. .Cl. ⁶ , DB name) C03B 37/00-37/16 C03C 1/00-14/00

Claims (5)

(57) [Claims] 1. A flake glass in which metal oxide fine particles are dispersed, wherein the metal oxide fine particles are derived from colloid particles having a hydroxyl group and have a particle size of 1 to 300 nm.
Consisting of titanium oxide fine particles having a particle size of
The content of the titanium oxide fine particles is substantially 1 to 60% by weight in the form of single particles without agglomeration in the glass.
Visible dispersed and a wavelength of 400~800nm as
Light transmittance of 80% or more over the entire area
That, the surface is smooth metal oxide particulate dispersion glass flakes. 2. The transmittance of ultraviolet light having a wavelength of 350 nm or less is obtained.
5% der Ru claim 1, wherein the metal oxide particulate dispersion glass flakes. 3. The metal oxide according to claim 1 , wherein:
Cosmetics containing glass flakes dispersed in fine particles . 4. Colloidal particles (in terms of oxide) of (1) a hydrated metal oxide, a metal hydroxide, or a metal oxide having a hydroxyl group on its surface, respectively, in an amount of 0.3 to 20% by weight. Organic metal compound capable of polycondensation 5 to 50% by weight (3) Alcohol 10 to 50% by weight (4) Acid catalyst 0.001 to 5% by weight (5) Water balance However, the above-mentioned organic metal compound (2) and alcohol A total of 90% by weight or less of the solution of (3) is applied on a substrate having a smooth surface, and the applied solution is dried to peel off the applied film;
A method for producing flake glass in which metal oxide fine particles are dispersed, characterized by sintering. 5. The method according to claim 4, wherein the colloidal particles are hydrous titanium oxide (meta titanate).