JP6589724B2 - Method for producing composite - Google Patents

Description

The present invention relates to a method for producing a composite having a hydrotalcite structure.

Hydrotalcite is a kind of layered clay mineral, and it is used for a wide variety of applications such as cosmetics and additives for resins, taking advantage of its anion exchange ability. However, since hydrotalcite does not have UV-blocking ability (also called UV-blocking), inorganic pigments such as titanium oxide and zinc oxide, and organic UV absorbers are used in applications that require this performance. It is necessary to mix hydrotalcite and, for example, zinc oxide particles and uniformly disperse them.

When adding inorganic pigments such as zinc oxide and titanium oxide for cosmetics, etc., in order to efficiently block ultraviolet rays or to provide transparency, a method of dispersing inorganic pigments to a few tens of nanometers is used. It has been. However, normally, nanoparticles of inorganic pigments refined to a few tens of nanometers or less are strongly aggregated, making it difficult to uniformly disperse with hydrotalcite powder. As an example of a method for suppressing aggregation of inorganic pigment nanoparticles, for example, Patent Document 1 employs a technique of coating the surface of zinc oxide nanoparticles with silicon oxide or the like.

JP 2004-292282 A

However, according to the method of Patent Document 1, the steps of coating the zinc oxide particles and the steps of dispersing the coated zinc oxide particles are complicated, and it is still difficult to suppress the aggregation of the particles. Although there is a method of adding a dispersant, there are few types of dispersants that can disperse both nano-sized hydrotalcite particles and zinc oxide particles, and even if a suitable dispersant is found, the dispersant is a resin. And other components such as cosmetics may invalidate the particles, and the particles may remain agglomerated. Therefore, with the conventional technology, it has been difficult to uniformly disperse several tens of nanometers of inorganic pigment particles in the hydrotalcite powder.

By the way, in cosmetics applications, the shape of the particles is desired to be plate-like rather than granular. This is because the slipperiness is better than the granular particles, and the coverage and orientation are also excellent. Among conventional hydrotalcite-type particles, plate-shaped particles are already known as Mg-Al-based and Mg-Zn-Al-based hydrotalcite-type particles. However, in order to produce this, in many cases, a special apparatus such as a pressure vessel is required because it undergoes a reaction with hydrothermal heat.

In addition to Mg-Al and Mg-Zn-Al hydrotalcite particles, Zn-Al hydrotalcite particles are known, but conventional Zn-Al hydrotalcite particles are known. The particles are granular particles having an aspect ratio of 1 to 2, and there have been no reports of tabular particles. This is because Zn-Al-based hydrotalcite-type particles have a lower ability to retain anions between layers than Mg-Al-based hydrotalcite-type particles, and therefore Mg-Al-based or Mg-Zn-Al When the Zn-Al hydrotalcite-type particles are produced by diverting the synthetic method of hydrotalcite-based particles as they are, a part of the raw material water-soluble zinc compound (for example, zinc sulfate) is produced during the precursor formation. It is thought that it becomes zinc hydroxide and finally becomes zinc oxide, and the layered structure of hydrotalcite cannot be maintained. As a method for producing Zn-Al-based hydrotalcite-type particles, there is also a method of growing particles by hydrothermal reaction after removing zinc hydroxide by filtering the precursor slurry. However, plate-like particles cannot be obtained.

In view of the present situation, the present invention is capable of exhibiting ultraviolet shielding properties together with the anion exchange ability derived from the hydrotalcite structure, and also has good slipping properties, and is useful as a cosmetic or resin additive. It aims at providing the manufacturing method given easily and simply.

The present inventor succeeded in easily and simply producing a composite having zinc oxide particles on the surface of hydrotalcite-type particles while diligently examining hydrotalcite-type particles. This composite can exhibit both the anion exchange ability derived from the hydrotalcite structure and the ultraviolet shielding property derived from the zinc oxide particles, and is excellent in infrared shielding property and transparency, and can also exhibit slipperiness. . As a method for producing such a composite, the present inventor has found a production method in which after obtaining a predetermined precursor, the precursor is held in a predetermined high temperature and high humidity atmosphere. Not only is the process of mixing talcite particles and zinc oxide particles unnecessary, but it also eliminates the need for special equipment and equipment such as pressure vessels required for hydrothermal synthesis, etc. This is an industrially extremely useful technique. As a means for imparting ultraviolet shielding properties to the object, a method of surface treatment with an ultraviolet shielding material is also conceivable, but the manufacturing method of the present invention can exhibit ultraviolet shielding properties even if surface treatment is not essential. This is also advantageous in this respect. Thus, the inventors have conceived that the above problems can be solved, and have completed the present invention.

That is, the present invention is a method for producing a composite having zinc oxide particles on the surface of hydrotalcite-type particles, the step of obtaining a precursor using a raw material containing at least a zinc compound and an aluminum compound (I), And a step (II) of holding the precursor in an atmosphere having a temperature of 100 to 150 ° C. and a relative humidity of 75 to 100% RH.

The hydrotalcite-type particles preferably have an average plate surface diameter of 150 to 800 nm and an aspect ratio (average plate surface diameter of major axis / average thickness) of 4.0 to 20.0. Thereby, it becomes what was excellent in the feeling of application | coating to the skin at the time of including in cosmetics, and slipperiness.

The average particle diameter of the zinc oxide particles is preferably 1 to 100 nm. Thereby, when used for a resin composition or cosmetics, higher transparency can be exhibited.

The production method preferably further includes a step (III) of surface treatment with a compound having a silicon atom and / or an aliphatic group. As a result, in the resulting composite, it is possible to suppress excessive elution of zinc ions, reduce irritation to the skin, and exhibit an appropriate astringent action, as well as compatibility and dispersion between the composite and the resin or solvent. In addition to improving water repellency, it is useful not only for cosmetics but also for various applications such as additives to resins.

The production method of the present invention is a pressure vessel that can exhibit an ultraviolet-shielding property as well as anion exchange ability derived from a hydrotalcite structure, and has good slipperiness, and is useful as a cosmetic or resin additive. This is an industrially extremely useful technique because it can be easily and simply applied by simply holding the precursor at a high temperature and high humidity without introducing special equipment such as the above. In addition to the above performance, this composite is also excellent in odor adsorbing properties such as ammonia and acetic acid, so it is useful for cosmetics to which odor adsorbing properties are added, adsorbents, acid neutralizing agents and the like. .

2 is an X-ray diffraction pattern of the powder obtained in Example 1. FIG. In FIG. 1, the peak positions derived from the hydrotalcite-type particles and ZnO (zinc oxide particles) are marked. 3 is an X-ray diffraction pattern of the powder obtained in Example 2. FIG. 3 is an X-ray diffraction pattern of the powder obtained in Comparative Example 1. 3 is an X-ray diffraction pattern of the powder obtained in Comparative Example 2. 4 is an X-ray diffraction pattern of the powder obtained in Comparative Example 3. It is a scanning electron micrograph (SEM photograph) of the powder obtained in Example 1 (magnification: 50000 times). It is a scanning electron micrograph (SEM photograph) of the powder obtained in Example 2 (magnification: 50000 times). It is a scanning electron micrograph (SEM photograph) of the powder obtained in Comparative Example 1 (magnification: 50000 times). It is a scanning electron micrograph (SEM photograph) of the powder obtained in Comparative Example 2 (magnification: 50000 times). It is a scanning electron micrograph (SEM photograph) of the powder obtained in Comparative Example 3 (magnification: 50000 times). 2 is an absorbance spectrum of powders obtained in Examples 1 and 2 and Comparative Example 1.

Hereinafter, although the preferable form of this invention is demonstrated concretely, this invention is not limited only to the following description, In the range which does not change the summary of this invention, it can change suitably and can apply.

〔Production method〕
First, the manufacturing method of the composite which is the 1st aspect of this invention is demonstrated.
The production method of the present invention comprises a step (I) of obtaining a precursor using a raw material containing at least a zinc compound and an aluminum compound, and the precursor at a temperature of 100 to 150 ° C. and a relative humidity of 75 to 100% RH. And holding in an atmosphere (II). By adopting this production method, it has zinc oxide particles on the surface of hydrotalcite-type particles easily and simply without introducing special equipment and equipment such as pressure vessels required for hydrothermal synthesis. A complex can be obtained. By passing through steps (I) and (II), the hydrotalcite-type particles in the resulting composite have a plate shape. In addition, it can be judged from an electron micrograph such as a scanning electron micrograph (also referred to as SEM) that the composite has such a structure.
Hereinafter, each step will be further described.

<Process (I)>
Step (I) is a step of obtaining a precursor using a raw material containing a zinc compound and an aluminum compound. By applying this to the step (II), crystal growth to the plate-like particles proceeds in the step (II), and at the same time, zinc oxide particles are precipitated from the precursor or the hydrotalcite type particles. Thus, a composite having zinc oxide particles on plate-like hydrotalcite-type particles can be obtained easily and simply. The precursor obtained in step (I) may contain hydrotalcite type particles.

The raw material may further contain a compound containing a Group 2 element of the periodic table. It does not specifically limit as the said compound, For example, the compound containing magnesium, calcium, barium etc. is mentioned. Especially, when using a composite_body | complex as cosmetics, the compound containing magnesium and / or calcium is preferable. More preferably, it is a compound containing magnesium (also referred to as a magnesium compound). Note that it is also preferable not to use a compound containing a Group 2 element of the periodic table from the viewpoint of reducing irritation to the skin and increasing the aspect ratio.

From the viewpoint of facilitating production, the raw material is preferably a water-soluble salt or a salt soluble in water containing an acid. Specifically, the zinc compound is preferably at least one selected from the group consisting of zinc hydroxide, zinc oxide, basic zinc carbonate and zinc sulfate, and the compound containing a Group 2 element of the periodic table is It is at least one selected from the group consisting of hydroxides (magnesium hydroxide, etc.), oxides (magnesium oxide, etc.) and basic carbonates (basic magnesium carbonate, etc.) of group 2 elements of the periodic table. Preferably, the aluminum compound is at least one selected from the group consisting of aluminum hydroxide, aluminum oxide and aluminum sulfate. By using these raw materials, hydrotalcite-type particles can be obtained more easily and simply. For example, a solution in which an aluminum compound is dissolved in a solvent, a solution in which a zinc compound is dissolved in a solvent, and the like may be prepared and then mixed, or each compound may be dissolved in a solvent. At this time, each compound does not necessarily need to be completely dissolved, and part of the compound may remain undissolved.

The amount of the raw material used is such that when a compound containing a Group 2 element in the periodic table is used, the total amount of the compound containing the zinc compound and the Group 2 element in the periodic table is 1 mol per 1 mol of the aluminum equivalent of the aluminum compound. It is preferably set to 1.0 to 3.5 mol in terms of metal, more preferably 1.5 to 2.5 mol. When a compound containing a Group 2 element in the periodic table is not used, it is preferable that the zinc equivalent of the zinc compound is set to 1.0 to 3.5 mol with respect to 1 mol of the aluminum equivalent of the aluminum compound. More preferably, it is 1.5-2.5 mol.

Here, in the step (II), 1 to 30% by mass of the zinc compound contained in the precursor can be zinc oxide. Accordingly, the amount of the zinc compound used is excessive in comparison with the target metal composition ratio of hydrotalcite in the plate-like hydrotalcite-type particles having zinc oxide particles on the surface obtained after the step (II). It is preferable to do. For example, plate-like hydrotalcite-type particles having the following composition in step (II):
(Zn) _0.67 (Al) _0.33 (OH) ₂ (CO ₃ ²⁻ ) _0.165 · mH ₂ O
When it is going to obtain, it is suitable that the usage-amount of a zinc compound shall be 2.02-2.6 mol with respect to 1 mol of aluminum of an aluminum compound.

The raw material may be pulverized in advance by a known dry or wet pulverization method such as a hammer mill, a jet mill, a bead mill, or a fritche mill, and then subjected to step (I).

In the step (I), the raw materials are preferably mixed in the presence of a solvent.
It does not specifically limit as a solvent, Water, an organic solvent, and these mixtures are mentioned, 1 type (s) or 2 or more types can be used. Examples of the organic solvent include alcohol, acetone, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, dioxane, and the like. Examples of the alcohol include monovalent water-soluble alcohols such as methanol, ethanol, and propanol; 2 such as ethylene glycol and glycerin. Water-soluble alcohol having a valency or higher; The solvent is preferably water, and more preferably ion-exchanged water.

In the step (I), the raw material is preferably neutralized with an alkali component. That is, in the step (I), it is preferable to neutralize after mixing the raw materials. In that case, it is preferable to mix a raw material and an alkali component so that pH of the liquid mixture of a raw material and an alkali component may be 7 or more. More preferably, mixing is performed so that the pH of the mixed solution of the raw material and the alkali component is 7.5 or more. At this time, for example, the alkali component may be dissolved in water and then added to the raw material and mixed, or the alkali component may be mixed as a powder.

Although it does not specifically limit as said alkali component, For example, an alkali metal salt etc. are mentioned, 1 type (s) or 2 or more types can be used. The alkali metal salt is, for example, a salt of an alkali metal such as lithium, sodium, or potassium, and examples of the salt include hydroxide, carbonate, bicarbonate, silicate, aluminate, and organic amine salt. . Of these, sodium hydroxide, sodium carbonate, sodium hydrogen carbonate and the like are preferable.

Here, when carbonate is not used as a raw material, or when the product does not satisfy the following formula (1) even when carbonate is used, carbon dioxide gas may be used separately. Carbon dioxide gas may be used in any operation as long as it is in step (I) or (II).

In the step (I), after mixing the raw materials and / or neutralizing, it is preferable to maintain a predetermined temperature as necessary and stir for a predetermined time. The holding temperature and stirring time are not limited, but for example, the holding temperature is preferably 20 to 80 ° C. and the stirring time is 5 to 300 minutes from the viewpoint of aligning the size and shape of the particles.

In the step (I), when a solvent is used, it is preferable to dry the obtained slurry (raw material mixture). This drying may be performed so that the solvent is removed from the slurry, and the drying means is not particularly limited. For example, vacuum drying, heat drying and the like can be mentioned. The slurry may be dried as it is, or may be filtered and washed with water and then dried. In the case of drying after filtering and washing with water, it is also preferable to dry by spray drying after adding a solvent to form a slurry.

It is preferable to perform pulverization after the drying. That is, it is preferable that the said process (I) includes the neutralization process which neutralizes a raw material in presence of a solvent, the drying process of the slurry obtained by this neutralization, and the grinding | pulverization process of what was dried. There are no particular limitations on the pulverization method and pulverization conditions, and for example, a ball mill, a reiki machine, a force mill, a hammer mill, a jet mill or the like can be used.

<Process (II)>
Step (II) is a step of holding the precursor obtained in the above step (I) in an atmosphere at a temperature of 100 to 150 ° C. and a relative humidity of 75 to 100% RH (also referred to as a wet atmosphere step). In the above production method, unlike the conventional method of hydrothermal or normal pressure reaction, it has the above-described structure by a simple means by passing through a process of simply holding the precursor in a high temperature and high humidity atmosphere. A composite can be obtained and a special device such as a pressure vessel can be dispensed with. That is, the manufacturing equipment can be simplified.

In the step (II), the precursor is held at a temperature of 100 to 150 ° C. When the temperature is 100 ° C. or higher, plate formation is promoted and zinc oxide particles are deposited on the surface. Preferably it is 105 degreeC or more, More preferably, it is 110 degreeC or more, More preferably, it is 115 degreeC or more. Moreover, it is preferable to set it as 145 degrees C or less from a viewpoint of manufacturing cost or equipment specification. More preferably, it is 140 degrees C or less.
In the present specification, the holding temperature in the step (II) means the highest temperature reached in the step.
In addition, since the fluctuation | variation of temperature may bring about a change in the crystal growth of a plate-like particle | grain, it is preferable that the difference of the upper limit and the minimum of temperature during holding shall be 10 degrees C or less.

The step (II) is also performed in an atmosphere having a relative humidity of 75 to 100% RH. From the viewpoint of promoting plate formation, the relative humidity is preferably 80% RH or more. Moreover, it is preferable to set it as 95% RH or less from a viewpoint of manufacturing cost or equipment specification, More preferably, it is 90% RH or less.
In the present specification, the relative humidity in the step (II) means the maximum reached humidity in the step.
In addition, since the fluctuation | variation of relative humidity may bring about a change in the crystal growth of a plate-like particle | grain, it is preferable that the difference of the upper limit and the minimum of the humidity during holding | maintenance shall be 10% or less.

The holding time under the above-mentioned conditions may be a time sufficient for the precursor to grow into a plate-like particle. For example, it is preferably 1 to 300 hours. When the holding time is within this range, crystallization proceeds more sufficiently and the productivity is excellent. More preferably, it is 3-200 hours, More preferably, it is 6-180 hours.

<Other processes>
In the above production method, in addition to the steps (I) to (II) described above, one or more pulverization, classification, washing, hydrothermal, aging, firing, substitution of interlayer ions, surface coating, etc., as necessary These steps may be included. Other steps are not particularly limited. For example, it is preferable to pulverize and classify coarse particles as long as the plate-like structure and the composite are not destroyed. The method and conditions for pulverization / classification are not particularly limited, and can be carried out using, for example, a ball mill, a lye mill, a force mill, a hammer mill, a jet mill, an air classifier, a vibrating sieve, or the like.

Among the other processes, it is preferable to include a surface coating process. That is, it is preferable to include a step of surface-treating part or all of the surface of the composite with one or more surface coating agents. With conventional particles, functions (eg, odor adsorbability, oil absorption, etc.) derived from the surface of the substrate decrease when surface treatment is performed, but the composite of the present invention has sufficient slip even if the surface treatment amount is small. In order to demonstrate its properties, it has an advantage over conventional particles in that the functional deterioration such as odor adsorbability and oil absorption is small.

As the surface coating agent, both inorganic compounds and organic compounds can be suitably used. Although it does not specifically limit as an inorganic compound, For example, oxides, hydroxides, sulfates, carbonates, etc., such as silicon, calcium, barium, strontium, aluminum, zirconium, cerium, zinc, etc. are mentioned. Although it does not specifically limit as an organic compound, For example, silicone oil, fatty acid and its metal salt, hydrogen dimethicone, alkylsilane, alkoxysilane, silane coupling agent, titanium coupling agent, aluminum coupling agent, amino acid, nylon, carbomer and The metal salt, polyacrylic acid, trimethylpropanol, triethylamine, higher alcohol, etc. are mentioned.

Among the surface coating agents, compounds containing silicon atoms and / or aliphatic groups are preferred. That is, the production method preferably includes a step (III) of surface treatment with a compound having a silicon atom and / or an aliphatic group, and a part or all of the surface of the complex is composed of silicon atoms and It is preferable to coat with a compound having an aliphatic group. In addition to suppressing excessive elution of zinc ions and reducing irritation to the skin to express an appropriate astringent action, compatibility and dispersibility with resins and solvents are improved, and water repellency is also achieved. In order to improve, it becomes useful not only for cosmetics but also for various uses such as additives to resins. Particularly preferred as the compound is silica, hydrogen dimethicone, alkylsilane, higher fatty acid or a salt thereof, and stearic acid is preferred as the higher fatty acid.

The method for coating the surface of the hydrotalcite-type particles with the surface coating agent is not particularly limited. For example, when silica is used, a method of neutralizing a slurry containing hydrotalcite-type particles by adding sodium silicate and an acid can be used. Although the amount of surface coating is not particularly limited, for example, the proportion of the surface coating agent is preferably 0.001 to 30% by mass with respect to 100% by mass of the total amount of hydrotalcite-type particles. More preferably, it is 0.1-25 mass%.

<Composite>
By the production method of the present invention described above, a composite having zinc oxide particles on the surface of hydrotalcite-type particles (preferably plate-like hydrotalcite-type particles) is obtained. This complex will be further described below.

The plate-like hydrotalcite-type particles preferably contain at least a zinc element and an aluminum element. Among them, the following formula (1):
{(R) _z (Zn) _y } (Al) _x (OH) ₂ (A ⁿ⁻ ) _{x / n} · mH ₂ O (1)
(In the formula, R represents a Group 2 element of the periodic table. A ⁿ⁻ represents an n-valent interlayer anion. X is a number of 0.20 or more and 0.40 or less, and y is 0. .20 and 0.80 or less, z is a number of 0 or more and 0.40 or less and satisfies x + y + z = 1 and y ≧ z, where n is 1 or more and 4 It is the following integers, and m is more preferably 0 or more. Thereby, slipperiness is improved more and it becomes more useful by various uses, such as cosmetics.

In the above formula (1), the n-valent interlayer anion is not particularly limited, but hydroxide ion (OH ⁻ ), carbonate ion (CO ₃ ²⁻ ), and sulfate ion ( At least one selected from the group consisting of SO ₄ ²⁻ ) is preferred. Of these, carbonate ions are preferred.

R represents a Group 2 element in the periodic table. For example, magnesium (Mg), calcium (Ca), barium (Ba), etc. are mentioned. Especially, when using a hydrotalcite type particle | grain as cosmetics, a magnesium element or a calcium element is preferable. Most preferred is magnesium element.

x, y, and z are numbers satisfying 0.20 ≦ x ≦ 0.40, 0.20 <y ≦ 0.80, 0 ≦ z ≦ 0.40, x + y + z = 1, and y ≧ z.
When x, y and z are within the above ranges, the crystal structure is stable. From the viewpoint of further improving the stability, it is preferable to adjust x or the like so that [(z + y) / x] is 1.5 / 1 to 3/1. More preferably, it is adjusted to be 2/1.
From this viewpoint, x is preferably 0.25 or more, more preferably 0.30 or more, and preferably 0.35 or less, and particularly preferably x = 1/3 (= about 0.33).
y is preferably 0.25 or more, more preferably 0.30 or more, and preferably 0.75 or less, more preferably 0.70 or less.
z is preferably 0.39 or less, and more preferably 0.38 or less. Among these, z = 0 is preferable from the viewpoint of reducing basicity.

n is a number satisfying 1 ≦ n ≦ 4 and may be appropriately adjusted depending on the valence of the interlayer anion. Preferably it is an integer of 1 to 3, more preferably 2.

m is a number of 0 or more. This m can be theoretically obtained by analyzing the crystal structure, but in reality, it is difficult to accurately measure the presence of the adhering water. Theoretically, it is preferably 0 or more and less than 5, for example.

Most preferably, the plate-like hydrotalcite type particles are represented by the following formula (2):
(Zn) _0.67 (Al) _0.33 (OH) ₂ (CO ₃ ²⁻ ) _0.165 · mH ₂ O (2)
It is a particle | grain represented by these. With this structure, the crystal structure is extremely stable, and the effects of the present invention can be more fully exhibited. This structure can be confirmed from JCPDS card 00-048-1023.

The average particle diameter of the zinc oxide particles is preferably 1 to 100 nm. Thereby, when used for a resin composition or cosmetics, higher transparency can be exhibited. The lower limit of the average particle diameter is preferably 5 nm or more, more preferably 10 nm or more. The upper limit is preferably 100 nm or less, and more preferably 80 nm or less.
In the present specification, the average particle diameter of the zinc oxide particles can be determined according to the method described in Examples described later.

[Use]
Next, the use of the composite obtained by the production method of the present invention will be described.
The composite can exhibit an ultraviolet ray shielding property as well as an anion exchange ability derived from the hydrotalcite structure, has a good slip property, and is excellent in the feeling of application to the skin when it is included in cosmetics. In addition, it has excellent odor adsorption performance such as ammonia and acetic acid and phosphorus compound adsorption performance. Therefore, it can be used for various uses such as cosmetics, pharmaceuticals, quasi drugs, adsorbents, catalysts, resin additives, acid neutralizers and the like. Among them, a cosmetic material that is particularly useful as a cosmetic raw material and includes the above composite is one aspect of the present invention. The composite may be combined with another inorganic material or organic material to form a composite material. For example, the composite may be mixed or embedded in an organic material such as resin or plastic at an arbitrary ratio to form a resin composition, or the composite may be used as an odor adsorbent or the like as a film or sheet. It is also suitable to mix in a resin composition that gives a molded product. Thus, the resin composition containing the composite and the resin component is also one aspect of the present invention. Below, the said cosmetics and resin composition are further demonstrated.

<Cosmetics>
The cosmetics contain the above composites, so that they have good slippage and excellent touch feeling on the skin when they are included in cosmetics, and also have excellent ultraviolet shielding properties, infrared shielding properties, and soft focus effects. A sebum adsorption effect can also be expected. Therefore, it is particularly suitable for the needs of the current market. The cosmetic is not particularly limited, and examples thereof include foundations, makeup bases, sunscreens, eye shadows, blushers, mascaras, lipsticks, antiperspirants, oil removing paper, scrub agents and the like. Among these, a foundation is particularly suitable.

In addition to the composite of the present invention, the cosmetic may contain one or more other components as necessary. Although other components are not specifically limited, For example, the organic solvent and a dispersing agent other than the arbitrary aqueous component and oil-based component normally used in the cosmetics field | area are mentioned. Specifically, oil; surfactant; moisturizer; higher alcohol; sequestering agent; various polymers (natural, semi-synthetic, synthetic or inorganic, water-soluble or oil-soluble polymers); UV screening agent; other Various extractants; Inorganic and organic pigments; Various powders such as inorganic and organic clay minerals; Inorganic and organic pigments treated with metal soap or silicone; Colorants such as organic dyes; Preservatives; Antioxidants A pigment, a thickener, a pH adjuster, a fragrance, a cooling agent, an astringent, a bactericidal agent, a skin activator, and the like. The content of these components is not particularly limited as long as the effects of the present invention are not impaired.

The oil content is not particularly limited. For example, avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, persic oil, wheat germ oil, Southern oil, castor oil , Linseed oil, safflower oil, cottonseed oil, eno oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, cinnagari oil, Japanese kiri oil, jojoba oil, germ oil, triglycerin, glyceryl trioctanoate, tri Cured oils such as glyceryl isopalmitate, cocoa butter, coconut oil, horse fat, palm oil, beef tallow, sheep tallow, palm kernel oil, pork tallow, beef bone fat, owl kernel oil, hydrogenated beef tallow, hydrogenated palm oil, hydrogenated castor oil , Beef leg fat, mole, beeswax, candelilla wax, cotton wax, carnauba wax, bayberry wax, ibotarou, whale wax, montan wax, nukarou, la Phosphorus, kapok wax, lanolin acetate, liquid lanolin, sugar cane wax, lanolin fatty acid isopropyl, hexyl laurate, reduced lanolin, jojoballow, hard lanolin, shellac wax, POE lanolin alcohol ether, POE lanolin alcohol acetate, POE cholesterol ether, lanolin fatty acid polyethylene glycol POE hydrogenated lanolin alcohol ether, liquid paraffin, ozokerite, pristane, paraffin, ceresin, squalene, petrolatum, microcrystalline wax and the like.

Examples of the surfactant include lipophilic nonionic surfactants, hydrophilic nonionic surfactants, and other surfactants. The lipophilic nonionic surfactant is not particularly limited. For example, sorbitan monooleate, sorbitan monoisostearate, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan sesquioleate, sorbitan trioleate Sorbitan fatty acid esters such as diglycerol sorbitan tetra-2-ethylhexylate, diglycerol sorbitan tetra-2-ethylhexylate, mono-cotton oil fatty acid glycerin, glyceryl monoerucate, glyceryl sesquioleate, glyceryl monostearate, α, α ' -Glycerol polyglycerin fatty acids such as glyceryl oleate, glyceryl monooleate, glyceryl monostearate, and propylene glycol such as propylene glycol monostearate Examples include recall fatty acid esters, hardened castor oil derivatives, and glycerin alkyl ethers.

The hydrophilic nonionic surfactant is not particularly limited, and examples thereof include POE sorbitan fatty acid esters such as POE sorbitan monooleate, POE sorbitan monostearate, POE sorbitan tetraoleate, POE sorbite monolaurate, and POE sorbite mono. POE sorbite fatty acid esters such as oleate, POE sorbite pentaoleate, POE sorbite monostearate, POE glycerin fatty acid esters such as POE glycerin monostearate, POE glycerin monoisostearate, POE glycerin triisostearate, POE POE fatty acid esters such as monooleate, POE distearate, POE monodiolate, ethylene glycol stearate, POE lauryl ether, POE POE alkyl ethers such as yl ether, POE stearyl ether, POE behenyl ether, POE 2 -octyldodecyl ether, POE cholestanol ether, POE alkyl phenyl ethers such as POE octyl phenyl ether, POE nonyl phenyl ether, POE dinonyl phenyl ether Pluronic type such as brulonic, POE / POP cetyl ether, POE / POP2-decyltetradecyl ether, POE / POP monobutyl ether, POE / POP hydrogenated lanolin, POE / POP alkyl ethers such as POE / POP glycerin ether, Tetronic PEO / TetraPOP ethylenediamine condensates, POE castor oil, POE hydrogenated castor oil, POE hydrogenated castor oil monoisos POE castor oil triisostearate, POE cured castor oil monopyroglutamic acid monoisostearic acid diester, POE castor oil cured castor oil derivatives such as POE cured castor oil maleic acid, POE beeswax lanolin derivatives such as POE sorbite beeswax, Alkanolamides such as coconut oil fatty acid diethanolamide, lauric acid monoethanolamide, fatty acid isopropanolamide, POE propylene glycol fatty acid ester, POE alkylamine, POE fatty acid amide, sucrose fatty acid ester, POE nonylphenyl formaldehyde condensate, alkylethoxydimethylamine Examples thereof include oxide and trioleyl phosphate.

Examples of other surfactants include anionic surfactants such as metal soaps, higher alkyl sulfates, POE lauryl sulfate triethanolamine, alkyl ether sulfates, alkyltrimethylammonium salts, alkylpyridinium salts, and alkyl quaternary salts. Examples thereof include cationic surfactants such as ammonium salts, alkyldimethylbenzylammonium salts, POE alkylamines, alkylamine salts, and polyamine fatty acid derivatives, amphoteric surfactants such as imidazoline-based amphoteric surfactants, and betaine-based surfactants.

The moisturizing agent is not particularly limited. For example, xylitol, sorbitol, maltitol, chondroitin sulfate, hyaluronic acid, mucoitin sulfate, caronic acid, atelocollagen, cholesteryl-12-hydroxystearate, sodium lactate, bile salt, dl-pyrrolidone Examples thereof include carboxylate, short-chain soluble collagen, diglycerin (EO) PO adduct, Izayoi rose extract, yarrow extract, and merirot extract.

The higher alcohol is not particularly limited. For example, linear alcohols such as lauryl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, cetostearyl alcohol, monostearyl glycerin ether (batyl alcohol), 2-decyltetra Examples thereof include branched chain alcohols such as decinol, lanolin alcohol, cholesterol, phytosterol, hexyldodecanol, isostearyl alcohol, and octyldodecanol.

The sequestering agent is not particularly limited. For example, 1-hydroxyethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid tetrasodium salt, sodium citrate, sodium polyphosphate, metaphosphoric acid Examples thereof include sodium, gluconic acid, phosphoric acid, citric acid, ascorbic acid, succinic acid, edetic acid and the like.

The natural water-soluble polymer is not particularly limited. For example, gum arabic, gum tragacanth, galactan, guar gum, carob gum, caraya gum, carrageenan, pectin, agar, quince seed (malmello), alge colloid (gypsum extract), starch (rice, Corn, potato, wheat), plant polymers such as glycyrrhizic acid, microbial polymers such as xanthan gum, dextran, succinoglucan and pullulan, and animal polymers such as collagen, casein, albumin and gelatin. .

The semi-synthetic water-soluble polymer is not particularly limited. For example, starch-based polymers such as carboxymethyl starch and methylhydroxypropyl starch, methylcellulose, nitrocellulose, ethylcellulose, methylhydroxypropylcellulose, hydroxyethylcellulose, sodium cellulose sulfate, Examples thereof include cellulose polymers such as hydroxypropylcellulose, sodium carboxymethylcellulose (CMC), crystalline cellulose and cellulose powder, and alginic acid polymers such as sodium alginate and propylene glycol alginate.

The synthetic water-soluble polymer is not particularly limited, and examples thereof include vinyl polymers such as polyvinyl alcohol, polyvinyl methyl ether, and polyvinyl pyrrolidone, polyoxyethylene polymers such as polyethylene glycol 20000, 40000, and 60000, and polyoxyethylene. Examples include polyoxypropylene copolymer copolymer polymers, acrylic polymers such as sodium polyacrylate, polyethyl acrylate, and polyacrylamide, polyethyleneimine, and cationic polymers.

The inorganic water-soluble polymer is not particularly limited, and examples thereof include bentonite, silicate A1Mg (beegum), laponite, hectorite, and silicic anhydride.

The ultraviolet screening agent is not particularly limited. For example, paraaminobenzoic acid (hereinafter abbreviated as PABA), PABA monoglycerin ester, N, N-dipropoxy PABA ethyl ester, N, N-diethoxy PABA ethyl ester, N, N- Benzoic acid UV screening agents such as dimethyl PABA ethyl ester and N, N-dimethyl PABA butyl ester; Anthranilic acid UV screening agents such as homomenthyl-N-acetylanthranylate; Amyl salicylate, Menthyl salicylate, Homomentil salicylate, Octyl Salicylic acid UV screening agents such as salicylate, phenyl salicylate, benzyl salicylate, p-isopropanol phenyl salicylate; octyl cinnamate, ethyl-4-isopropyl cinnamate, methyl-2,5 Diisopropylcinnamate, ethyl-2,4-diisopropylcinnamate, methyl-2,4-diisopropylcinnamate, propyl-p-methoxycinnamate, isopropyl-p-methoxycinnamate, isoamyl-p-methoxycinnamate, 2- Ethoxyethyl-p-methoxycinnamate, cyclohexyl-p-methoxycinnamate, ethyl-α-cyano-β-phenylcinnamate, 2-ethylhexyl-α-cyano-β-phenylcinnamate, glyceryl mono-2-ethylhexa Cinnamic acid-based ultraviolet screening agents such as noyl-diparamethoxycinnamate; 2,4-dihydroxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone , 2, 2 ′, 4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4′-methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonate, Benzophenone-based ultraviolet shielding agents such as 4-phenylbenzophenone, 2-ethylhexyl-4′-phenyl-benzophenone-2-carboxylate, 2-hydroxy-4-n-octoxybenzophenone, 4-hydroxy-3-carboxybenzophenone; 3 -(4'-methylbenzylidene) -d, l-camphor, 3-benzylidene-d, l-camphor, urocanic acid, urocanic acid ethyl ester, 2-phenyl-5-methylbenzoxazole, 2,2'-hydroxy -5-methylphenylbenzo Riazole, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, dibenzalazine, dianisoylmethane, 4-methoxy-4 ′ -T-butyldibenzoylmethane, 5- (3,3-dimethyl-2-norbornylidene) -3-pentan-2-one and the like.

Other drug components are not particularly limited and include, for example, vitamin A oil, retinol, retinol palmitate, inosit, pyridoxine hydrochloride, benzyl nicotinate, nicotinamide, nicotinic acid DL-α-tocopherol, magnesium ascorbate phosphate, 2 Vitamins such as -O-α-D-glucopyranosyl-L-ascorbic acid, vitamin D2 (ergocaciferol), dl-α-tocopherol, dl-α-tocopherol acetate, pantothenic acid, biotin; estradiol, ethinylestradiol, etc. Hormones; amino acids such as arginine, aspartic acid, cystine, cysteine, methionine, serine, leucine and tryptophan; anti-inflammatory agents such as allantoin and azulene; whitening agents such as arbutin; astringents such as tannic acid; L Menthol, cooling agents of camphor; and, sulfur, lysozyme chloride, pyridoxine chloride.

There are no particular limitations on the various extracts, for example, Dokudami extract, Oat extract, Merirot extract, Odorikosou extract, Licorice extract, Peonies extract, Soap extract, Loofah extract, Kina extract, Yukinoshita extract, Clara extract, Kouhone extract, Fennel Extract, Primrose Extract, Rose Extract, Giant Extract, Lemon Extract, Shikon Extract, Aloe Extract, Shobu Root Extract, Eucalyptus Extract, Horsetail Extract, Sage Extract, Thyme Extract, Tea Extract, Seaweed Extract, Cucumber Extract, Clove Extract, Raspberry Extract, Melissa Extract , Carrot extract, horse chestnut extract, peach extract, peach leaf extract, mulberry extract, cornflower extract, hamamelis extract, placenta extract, thymus extract, silk extract, licorice Kiss, and the like.

Various powders include, for example, bengara, yellow iron oxide, black iron oxide, mica titanium, iron oxide coated mica titanium, titanium oxide coated glass flakes and other bright colored pigments, mica, talc, kaolin, sericite, titanium dioxide. Inorganic powders such as silica and organic powders such as polyethylene powder, nylon powder, cross-linked polystyrene, cellulose powder, and silicone powder. Preferably, a part or all of the powder component is hydrophobized by a known method with substances such as silicones, fluorine compounds, metal soaps, oil agents, acyl glutamates in order to improve sensory characteristics and cosmetic durability. Is.

<Resin composition>
The resin composition includes the composite and a resin component. The compounding quantity of the composite in a resin composition can be suitably selected according to the desired use and the characteristic of the resin component to be used. For example, when using an epoxy resin, an acrylic resin or the like as the resin component, it is preferable to blend 1 to 200 parts by mass of the above composite with respect to 100 parts by mass of the resin component, using a polyethylene resin or a soft vinyl chloride resin. When doing, it is preferable to mix | blend 1-300 mass parts of the said composites with respect to 100 mass parts of resin components. A resin composition can be prepared by using a blender / kneader such as a conical blender, a V blender, a ribbon blender, a Henschel mixer, a Banbury mixer, or a two-roller.

Moreover, a hydrotalcite-containing resin composition (molded article) can be formed from the resin composition. The shape of the molded body is not particularly limited, and examples include other shapes such as a string shape, a plate shape, a rod shape, and a pellet shape in addition to a sheet shape and a film shape.
When obtaining a sheet-like hydrotalcite-containing resin composition, for example, the composite is 1 to 200 parts by mass, the calcium-zinc stabilizer is 3 to 5 parts by mass, and the plastic is 100 parts by mass of the polyvinyl chloride resin. It is preferable to mix 30-100 parts by mass of dioctyl phthalate which is an agent, and knead at 100-180 ° C. with a two-roll, whereby a flexible sheet-like hydrotalcite-containing resin composition is suitable. Can get to.

When obtaining a film-like hydrotalcite-containing resin composition, for example, 1 to 50 parts by mass of the above composite is blended with 100 parts by mass of polyethylene terephthalate resin, and 250 to 300 by a biaxial extruder or an inflation processing machine. It is preferable to knead and mold at ° C.

When obtaining a hydrotalcite-containing resin composition having other shapes, for example, 1 to 100 parts by mass of the above composite is blended with 100 parts by mass of polypropylene resin, and kneaded at 170 to 200 ° C. with a biaxial extruder. By molding, a hydrotalcite-containing resin composition having a string shape, a plate shape, a rod shape, a pellet shape, or the like can be obtained. In addition, for example, a three-dimensional hydrotalcite-containing resin composition can be obtained by processing and molding a pellet-shaped hydrotalcite-containing resin composition at 170 to 200 ° C. using an injection molding machine.

In order to describe the present invention in detail, examples will be given below, but the present invention is not limited to these examples. Unless otherwise specified, “%” means “% by weight (mass%)”.

Example 1
-(1) Neutralization-
72.5 g of zinc sulfate heptahydrate, 81.2 mL of a 354 g / L aqueous solution of aluminum sulfate (28.7 g as Al ₂ (SO ₄ ) ₃ ), 34.1 mL of a 297 g / L aqueous solution of magnesium sulfate (as MgSO ₄₎ 10.1 g) was mixed to obtain a metal salt mixed aqueous solution to which ion exchange water was added so that the total amount became 350 mL. Separately, 46.7 mL of a 720 g / L sodium hydroxide aqueous solution and 26.7 g of sodium carbonate were mixed to obtain an alkali mixed aqueous solution to which ion-exchanged water was added so that the total amount became 350 mL. In a 1 L round bottom flask, 50 mL of ion exchange water was added, and these aqueous solutions were added under stirring. The pH of the slurry at this time was 9. Then, the slurry was obtained by stirring for 10 minutes at 50 degreeC.

-(2) Drying and grinding-
The slurry obtained by the above “(1) neutralization” was filtered and washed with water until the electric conductivity of the washing liquid became 100 μS / cm or less. The obtained cake was mixed with water, and dried with a spray drying apparatus (atomizer method, manufactured by Okawara Kako Co., Ltd., BDP-22 type) under the conditions of a disk rotation speed of 16000 rpm and an outlet drying temperature of 105 ° C. A site precursor powder was obtained.

-(3) Wet atmosphere process-
1 g of the powder obtained by the above “(2) Drying / Crushing” is put into a glass petri dish having an inner diameter of 27 mm and a height of 15 mm, and an unsaturated type high acceleration life test apparatus (manufactured by Hirayama Seisakusho, HASTEST PC-242HSR2 The temperature was adjusted from room temperature to 120 ° C. and a relative humidity of 85% RH over 80 minutes, maintained at 120 ° C. and a relative humidity of 85% RH for 118 hours, and then the heater was turned off and cooled to room temperature. In addition, this process was performed in air | atmosphere. In this way, a powder (1) was obtained.
From the fact that the peak derived from zinc oxide was confirmed in the powder X-ray diffraction pattern and from the SEM image, it was judged that the particles of zinc oxide were present on the hydrotalcite particles (FIGS. 1-1 and 2-). 1).

Example 2
In Example 1, except that the raw materials in “(1) Neutralization” and the retention time in “(3) Wet atmosphere process” were changed as shown in Table 1, powders ( 2) was obtained.
From the fact that the peak derived from zinc oxide was confirmed in the powder X-ray diffraction pattern and from the SEM image, it was determined that the particles of hydrotalcite had zinc oxide particles (FIGS. 1-2 and 2- 2).

Comparative Example 1
In Example 1, the raw materials in “(1) Neutralization” were changed as shown in Table 1, and 1 g of the powder obtained by “(2) Drying / Crushing” had an inner diameter of 27 mm and a height of 15 mm. In a constant temperature and humidity chamber (Espec Corp., LH-113), adjust from room temperature to 85 ° C, relative humidity 85% RH over 15 minutes, 85 ° C, relative humidity 85% RH For 166 hours, and then the heater was turned off and cooled to room temperature. In addition, this process was performed in air | atmosphere. Thus, powder (c1) was obtained.
From the powder X-ray diffraction pattern and SEM image, zinc oxide particles could not be confirmed in this powder (see FIGS. 1-3 and 2-3).

Comparative Example 2
1 g of the powder obtained by “(2) Drying and pulverization” in Example 1 was placed in a glass petri dish having an inner diameter of 27 mm and a height of 15 mm, and placed in a thermo-hygrostat (Espec Corp., LH-113). The temperature was adjusted from room temperature to 85 ° C. and a relative humidity of 85% RH over 15 minutes, held at 85 ° C. and a relative humidity of 85% RH for 118 hours, and then the heater was turned off and cooled to room temperature. In addition, this process was performed in air | atmosphere. In this way, powder (c2) was obtained.
From the powder X-ray diffraction pattern and SEM image, zinc oxide particles could not be confirmed in this powder (see FIGS. 1-4 and 2-4).

Comparative Example 3
1 g of the powder obtained by “(2) Drying and pulverization” in Example 2 was put in a glass petri dish having an inner diameter of 27 mm and a height of 15 mm, and placed in a thermo-hygrostat (manufactured by Espec, LH-113). The temperature was adjusted from room temperature to 85 ° C. and a relative humidity of 85% RH over 15 minutes, held at 85 ° C. and a relative humidity of 85% RH for 22 hours, and then the heater was turned off and cooled to room temperature. In addition, this process was performed in air | atmosphere. In this way, powder (c3) was obtained.
From the powder X-ray diffraction pattern and SEM image, zinc oxide particles could not be confirmed in this powder (see FIGS. 1-5 and 2-5).

The physical properties of the powders obtained in each Example and Comparative Example, and the precursor (product in the case of not performing Step (II)) used in Step (II) were evaluated according to the following methods. .

1. X-ray diffraction A powder X-ray diffraction pattern (also simply referred to as an X-ray diffraction pattern) was measured under the following conditions. For example, X-ray diffraction patterns of the powders obtained in Examples 1 and 2 and Comparative Examples 1 to 3 are shown in FIGS. In these figures, the peaks marked with ■ are peaks derived from Zn _0.67 Al _0.33 (OH) ₂ (CO ₃ ) _0.165 · xH ₂ O (plate-like hydrotalcite-type particles). The peaks marked with ◯ are those derived from ZnO (zinc oxide particles).

-Analysis conditions-
Machine used: Rigaku Corporation, RINT-UltimaIII
Radiation source: CuKα
Voltage: 50kV
Current: 300mA
Sample rotation speed: 60 rpm
Divergence slit: 1.00mm
Divergence length restriction slit: 10 mm
Scattering slit: Open light receiving slit: Open scanning mode: FT
Counting time: 2.0 seconds Step width: 0.0200 °
Operation axis: 2θ / θ
Scanning range: 1.6000 to 70.000 °
Accumulation count: 1 times The following materials were used to identify hydrotalcite-type particles.
Zn _0.67 Al _0.33 (OH) ₂ (CO ₃ ) _0.165 · xH ₂ O: JCPDS card 00-048-1023
_{Mg 4 Al 2 (OH) 12} CO 3 · 3H 2 O: JCPDS Card 00-051-1525
The following materials were used to identify the zinc oxide particles.
JCPDS card 01-089-0510

2. SEM image The shape of the particles was observed with a field emission scanning electron microscope (JSM-7000F, manufactured by JEOL Ltd.). The electron micrograph of each powder is shown to FIGS. 2-1 to 2-5 (SEM photograph).

3. About 10 to 100 particles finer than the plate-like particles occupying a large number of each powder with an average particle diameter of zinc oxide particles by a field emission type transmission electron microscope (JEM-2100F, manufactured by JEOL Ltd.) An electron micrograph was taken. The average value of the major axis of 10 zinc oxide particles present on the surface of the particles on a straight line randomly drawn on this electron micrograph was taken as the average particle size of the zinc oxide particles of each powder. When it was difficult to measure the major axis, the measurement was performed using a photograph taken at an appropriately increased magnification. This operation was repeated 10 times by changing the powder photographed for each Example and Comparative Example, and the average value of the obtained particle diameters of the zinc oxide particles was calculated. The results are shown in Table 2-1.

4. Median diameter (D ₅₀ )
The particle size distribution was measured with a laser diffraction / scattering particle size analyzer (manufactured by HORIBA, model number: LA-950-V2).
First, 60 mL of a 0.025 wt% sodium hexametaphosphate aqueous solution was added to 0.1 g of a sample (sample powder), and 2 ultrasonic waves with a frequency of 20 kHz and an output of 90 W were applied using an ultrasonic homogenizer (US-600, manufactured by Nippon Seiki Seisakusho). A sample suspension was prepared by irradiation for 1 minute. Thereafter, an aqueous 0.025 wt% sodium hexametaphosphate solution is circulated through the sample circulator, and the suspension is added dropwise so that the transmittance is 80 to 95%. Measurement was performed after ultrasonic dispersion for 2 seconds. The results are shown in Table 2-1.

5. Using an electric field emission scanning electron microscope (manufactured by JEOL Ltd., JSM-7000F), an electron micrograph was taken for each powder with an average plate surface diameter, average thickness, and aspect ratio so that about 50-10,000 particles could be seen. did. The average value of the plate surface diameters of 20 particles on a straight line randomly drawn on this electron micrograph was taken as the average plate surface diameter of each powder. The average thickness (average value of the thickness of 20 particles) was calculated by the same method, and the aspect ratio was determined by (major axis of average plate surface diameter / average thickness). When it was difficult to measure the plate surface diameter and thickness, the measurement was carried out using a photograph taken at an appropriately increased magnification. This operation was repeated 10 times by changing the powder to be photographed for each example and comparative example, and the average value of the obtained aspect ratios was calculated. The results are shown in Table 2-1.

6. Elemental analysis The Mg, Zn and Al contents in each powder can be measured by the following method using inductively coupled plasma (ICP) emission spectroscopy.
Specifically, a spectroscope (manufactured by SII, ICP SPS3100) is used as follows, and measurement is performed by an internal standard method using scandium (Sc) as an internal standard element.
First, about 0.2 g of a sample is precisely weighed in a beaker, about 5 mL of hydrochloric acid is added and dissolved, filled into a 100 mL volumetric flask, and made up with ion-exchanged water. This was diluted 20 times for Mg content measurement, 50 times for Zn content measurement, 10 times for Al content measurement, and diluted with Sc standard solution so that the Sc concentration would be 10 ppm. The Mg, Zn and Al contents are calculated by measuring under the following measurement conditions and calculating the obtained raw data under the following calculation conditions. The results are shown in Table 2-2.

-Measurement conditions-
Using a spectroscope (ICP SPS3100, manufactured by SII), calibration curves were prepared at wavelengths of 279.55 nm (Mg), 213.86 nm (Zn), 396.15 nm (Al), and 361.49 nm (Sc), respectively. After that, the sample is measured.
As the concentration of the calibration curve sample,
Mg (ppm) = 50, 40, 30, 20, 10,
Zn (ppm) = 20, 16, 12, 8, 4,
Al (ppm) = 50, 40, 30, 20, 10
5 points are used.
In all the calibration curve samples, the Sc standard solution was added so that the Sc concentration was 10 ppm. The calculation conditions are as follows.
Each content (%) = raw data × 100 / sample weight (g) × dilution ratio / 10000

7, slipperiness (MIU, MMD)
Evaluation of slipperiness of each sample was performed by the following method.
Double-sided tape was affixed to the slide glass, about half a spoonful of powder (sample) was placed on the adhesive surface, the powder was spread with a cosmetic sponge, and a friction piece was set thereon. The slide glass was moved, and the average friction coefficient MIU and the variation value MMD of the average friction coefficient were measured from the load applied to the friction element. The measurement was performed with a friction tester (KES-SE, manufactured by Kato Tech). The results are shown in Table 2-2.
In addition, it can be said that the lower the MIU and MMD values, the smoother the sliding feeling is.

8. Evaluation as cosmetics (sensory evaluation)
(1) First, 20.00% by weight of powders obtained in Examples and Comparative Examples, mica (product name: Y-2300X, manufactured by Yamaguchi Mica) 24.83% by weight, sericite (product name: FSE, Sanshin) Mining Co., Ltd.) 29.79% by weight, spherical silicone (Product name: KSP-105, Shin-Etsu Chemical Co., Ltd.) 6.44% by weight, titanium oxide (Product name: R-3LD, Sakai Chemical Industry Co., Ltd.) 7 36% by weight, iron oxide (yellow) (product name: yellow iron oxide, manufactured by Pinoa) 1.10% by weight, iron oxide (red) (product name: Bengala, manufactured by Pinoa) 0.37% by weight, stearin Magnesium acid (product name: JPM-100, manufactured by Sakai Chemical Industry Co., Ltd.) 0.92% by weight and dimethyl silicone oil (product name: KF96, manufactured by Shin-Etsu Chemical Co., Ltd.) 9.20% by weight using a coffee mill For 1 minute and 30 seconds.
The obtained powdery mixture was weighed 0.8 g in a 20 mmφ diameter mold and held for 30 seconds at a pressure of 200 kgf / cm ² using a press machine to prepare a hydrotalcite-containing foundation. .

(2) Mica (product name: Y-2300X, manufactured by Yamaguchi Mica) 31.03 wt%, sericite (product name: FSE, manufactured by Sanshin Mining Co.) 37.24 wt%, spherical silicone (product name: KSP) -105, manufactured by Shin-Etsu Chemical Co., Ltd.) 8.05% by weight, titanium oxide (product name: R-3LD, manufactured by Sakai Chemical Industry Co., Ltd.) 9.20% by weight, iron oxide (yellow) (product name: yellow iron oxide, 1.38% by weight (product of Pinoa), iron oxide (red) (product name: Bengala, product of Pinoa) 0.46% by weight, magnesium stearate (product name: JPM-100, manufactured by Sakai Chemical Industry Co., Ltd.) 15% by weight and 11.49% by weight of dimethyl silicone oil (product name: KF96, manufactured by Shin-Etsu Chemical Co., Ltd.) were stirred and mixed using a coffee mill for 1 minute 30 seconds.
0.8 g of the obtained powdery mixture is measured in a 20 mmφ diameter mold and is held for 30 seconds at a pressure of 200 kgf / cm ² using a press machine to produce a hydrotalcite-free foundation. did.

(3) The foundation obtained in (1) and (2) above was applied to 10 panelists, and the skin touch when it was included in cosmetics was selected according to the criteria shown below. did. The test was conducted blind. The evaluation results are shown in Table 2-2.
(Evaluation criteria for coating feel)
A: The use feeling of the hydrotalcite-containing foundation (1) above is better than the use of the hydrotalcite-free foundation (2) above.
○: Both have the same coating feel.
X: The use feeling of the hydrotalcite-free foundation of the above (2) has a better coating feel than the use of the hydrotalcite-containing foundation of the above (1).

9. Evaluation of soft focus property The soft focus property of each sample was evaluated by the following method.
Weigh 0.3g of the sample and 2.7g of methylpolysiloxane (Momentive Performance Materials, Element14 * PDMS, 1000-JC), mix well, and then use a Hoover-type muller at a rotation speed of 100 rpm. The paste was prepared by rotating 100 times. The paste thus prepared was uniformly formed on a glass plate using a 3MIL applicator. The thus-obtained coating film was measured for haze value and total light transmittance with a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., NDH4000 type), and the transparency was evaluated. Table 3 shows the results.

10. Ultraviolet shielding property About each sample obtained by the said Example and comparative example, ultraviolet shielding property was measured as follows.
The sample powder is packed in a spectrophotometer (JASCO Corporation V-570 type spectrophotometer and ILN-472 type integrating sphere) measurement cell, and the reflectance in the wavelength region of 300 nm to 2400 nm using the spectrophotometer. Was measured.
The obtained diffuse reflection spectrum was converted into absorbance by the Kubelka-Munk method (FIG. 3). In FIG. 3, Comparative Example 1 is not illustrated because the absorbance is too low at 0.01 (substantially overlaps with the horizontal axis of KM = 0).

The powders obtained in Examples 1 and 2 were confirmed to have an ultraviolet shielding ability, a low MIU, and excellent slipperiness.

The composites produced by the production method of the present invention such as Examples 1 and 2 have zinc oxide particles on the surface of plate-like hydrotalcite-type particles, but these zinc oxide particles are not coated (uncoated particles) ). Here, since both the hydrotalcite-type particles and the zinc oxide particles are hydrophilic inorganic compounds, it is considered that they adhere well when mixed. However, since zinc oxide particles having a coating layer have the effect of suppressing the aggregation of particles, when supported on the hydrotalcite surface by a physical method such as mixing, the hydrotalcite has a coating layer. Zinc oxide particles easily fall off from the site surface. On the other hand, in the production method of the present invention, the zinc oxide particles are uniformly deposited on the surface of the hydrotalcite type particles simultaneously with the crystal growth of the hydrotalcite type particles, and therefore, between the plate-like hydrotalcite type particles and the zinc oxide particles. It is considered that there is no extra layer and the zinc oxide particles are firmly fixed. Therefore, when dispersed in cosmetics or resins, it is expected that hydrotalcite particles and zinc oxide particles will be difficult to separate.

Claims (4)

A method for producing a composite having zinc oxide particles on the surface of hydrotalcite-type particles,
Step (I) of obtaining a precursor using a raw material containing at least a zinc compound and an aluminum compound;
And a step (II) of holding the precursor in an atmosphere having a temperature of 100 to 150 ° C. and a relative humidity of 75 to 100% RH. 2. The hydrotalcite-type particles have an average plate surface diameter of 150 to 800 nm and an aspect ratio (average plate surface diameter / average thickness) of 4.0 to 20.0. A method for producing the composite according to 1. The average particle diameter of the said zinc oxide particle is 1-100 nm, The manufacturing method of the composite_body | complex of Claim 1 or 2 characterized by the above-mentioned. The said manufacturing method further includes the process (III) of surface-treating with the compound which has a silicon atom and / or an aliphatic group, The manufacturing method of the composite_body | complex in any one of Claims 1-3 characterized by the above-mentioned.