TW201716330A - Method for manufacturing flake-shaped hydrotalcite-type particle - Google Patents

Abstract

Provided is a manufacturing method with which it is possible to easily and conveniently provide flake-shaped hydrotalcite-type particles having superior glide, without the introduction of special devices or equipment. This method for manufacturing flake-shaped hydrotalcite-type particles includes: a step (I) in which a precursor is obtained using an aluminum compound and at least one compound selected from the group consisting of zinc compounds and compounds containing an element from group 2 of the periodic table as raw materials; and a step (II) in which the precursor is kept in an atmosphere with a temperature of 75-150 DEG C and a relative humidity of 75-100%. The half-width of peaks originating from a (003) plane of the precursor is 0.4 or greater.

Description

Method for producing platy hydrotalcite-type particles

The present invention relates to a method for producing a plate-like hydrotalcite-type particle.

A hydrotalcite-based layered clay mineral is widely used in various applications such as catalysts, pharmaceuticals, and additives for resins. In the use of cosmetic materials, it is expected to provide functions such as adsorption of excess sebum, or prevention of makeup removal and oil release, and the use of particulate hydrotalcite (referred to as hydrotalcite-type particles).

Most of the conventional hydrotalcite-type particles are Mg-Al-based hydrotalcite-type particles containing magnesium and aluminum as constituent elements (for example, see Patent Document 1). However, in addition to magnesium and aluminum, Mg-Zn-Al-based hydrotalcite-type particles containing zinc as a constituent element (for example, refer to Patent Document 2) or Zn-Al-based hydrotalcites containing zinc and aluminum as constituent elements are being developed. The type of particles (for example, refer to Patent Documents 3 to 6).

Patent Document 1: Japanese Patent Laid-Open Publication No. 2000-247633

Patent Document 2: Japanese Patent Laid-Open Publication No. 2004-299931

Patent Document 3: Japanese Patent Laid-Open Publication No. 2002-226826

Patent Document 4: Japanese Patent Laid-Open No. Hei 11-209258

Patent Document 5: Japanese Patent Laid-Open No. Hei 11-240886

Patent Document 6: Japanese Patent Laid-Open No. Hei 11-255973

Further, in the use of the cosmetic material, the shape of the particles is more preferably a plate shape than the granular shape. The reason for this is that the slidability is good compared with the granular particles, and the coating property or the alignment property is also excellent. Among the conventional hydrotalcite-type particles, those of the Mg-Al type or the Mg-Zn-Al type hydrotalcite type particles are known to have a plate shape. However, in order to manufacture a plate shape, in many cases, it is subjected to a reaction under hydrothermal conditions, and thus a special device such as a pressure vessel is required.

Further, the conventional Zn-Al-based hydrotalcite-type particles are granular particles having an aspect ratio of 1 to 2, and there have been no reports of plate-like particles. The main reason for this is that since the Zn-Al-based hydrotalcite-type particles have a lower ability to maintain anions between the layers than the Mg-Al-based hydrotalcite-type particles, the conventional Mg-Al system or Mg-Zn is directly used. - Method for synthesizing Al-based hydrotalcite-type particles, in which Zn-Al-based hydrotalcite-type particles are produced, a part of a water-soluble zinc compound (for example, zinc sulfate) of a raw material becomes zinc hydroxide in the formation of a precursor, and eventually becomes zinc oxide and cannot be formed. Maintain the layered structure of hydrotalcite. In addition, as a method of producing Zn-Al-based hydrotalcite-type particles, there is a method in which particles are removed by a hydrothermal reaction after removing the zinc hydroxide by filtering the precursor slurry (Patent Document 6 and the like). However, this method also fails to obtain plate-like particles.

In view of the above circumstances, an object of the present invention is to provide a method for producing a plate-like hydrotalcite-type particle which can easily and easily impart slidability without introducing a special device or equipment.

The present inventors made an effort to develop a method for producing platy hydrotalcite-type particles. During the study, it was found that after obtaining a specific precursor, only the precursor was maintained in a specific high temperature and high humidity environment, and unlike the reaction under hydrothermal conditions as in the conventional method, by simple means, A plate-shaped hydrotalcite-type particle excellent in slidability can be obtained. Such a manufacturing method is an industrially extremely useful method because it can eliminate special equipment and equipment such as a pressure vessel which is necessary for hydrothermal synthesis or the like, that is, the manufacturing equipment can be simplified. It is thus conceived that the above problems can be solved, thereby completing the present invention.

That is, the present invention is a method for producing a plate-like hydrotalcite-type particle, which is a method for producing a plate-shaped hydrotalcite-type particle, the method comprising the following steps (I) and (II): step (I): use selection At least one of a group consisting of a free zinc compound and a compound containing a Group 2 element of the periodic table and an aluminum compound as a raw material to obtain a precursor; and step (II): at a temperature of 75 to 150 ° C and a relative humidity of 75 to 100% The precursor is maintained in the RH environment, and the precursor has a half-height width of 0.4 or more from the peak of the (003) plane.

The precursor is preferably in the form of a powder before the step (II). Thereby, the crystal growth toward the plate-like particles can be further promoted.

The zinc compound is preferably at least one selected from the group consisting of zinc hydroxide, zinc oxide, basic zinc carbonate, and zinc sulfate. The aluminum compound is preferably at least one selected from the group consisting of aluminum hydroxide, aluminum oxide, and aluminum sulfate. By using these raw materials, plate-shaped hydrotalcite-type particles can be obtained more easily and simply.

The above production method is preferably a method of producing a plate-like hydrotalcite type particle represented by the following formula (1), (R) _1-x (Al) _x (OH) ₂ (A ^n- ) _{x / n} ‧ mH ₂ O (1)

Wherein R represents at least one element selected from the group consisting of a zinc element and a Group 2 element of the periodic table; A ^n- represents an interlayer anion of n valence; x and n respectively satisfy 0.2 ≦ x ≦ 0.4, 1 The number of conditions of ≦n≦4; m is a number of 0 or more). Such a plate-like hydrotalcite-type particle is excellent in slidability, and is useful for various uses such as cosmetics.

In the production method of the present invention, it is possible to easily and easily impart plate-like hydrotalcite-type particles excellent in slidability without introducing a special device or equipment such as a pressure vessel. Therefore, since the manufacturing equipment can be simplified, it is extremely useful in the industry. Further, the plate-like hydrotalcite-type particles obtained by the production method of the present invention are excellent in slidability, and can be preferably used in the use of a cosmetic material, and the adsorption performance of ammonia gas or a phosphorus compound is also excellent, so that the adsorption is added. It is also useful for applications such as cosmetic or adsorbent, acid neutralizing agents, and the like.

Fig. 1 is an X-ray diffraction pattern of the plate-like hydrotalcite-type particles obtained in Example 11.

Fig. 2-1 is an electron micrograph (magnification: 50,000 times) of the plate-shaped hydrotalcite-type particles obtained in Example 11 in such a manner that the thickness can be judged.

Fig. 2-2 is an electron micrograph (magnification: 20,000 times) of the plate-shaped hydrotalcite-type particles obtained in Example 11 in such a manner that the thickness can be judged.

Fig. 2-3 is an electron micrograph (magnification: 50,000 times) obtained by photographing the plate-like hydrotalcite-type particles obtained in Example 11 in such a manner as to judge the surface diameter of the plate.

Fig. 2-4 is an electron micrograph (magnification: 20,000 times) of the plate-shaped hydrotalcite-type particles obtained in Example 11 in such a manner that the surface diameter of the plate can be judged.

Fig. 3-1 is a graph comparing the temporal changes of the phosphate ion concentration in the case where the hydrotalcite-type particles obtained in Example 11 and Reference Example 1 are respectively adsorbed with potassium hydrogen phosphate (phosphate ion concentration) Initial value: 50 ppm).

Fig. 3-2 is a graph comparing the temporal changes of the phosphate ion concentration in the case where the hydrotalcite-type particles obtained in Example 11 and Reference Example 1 are respectively adsorbed with potassium hydrogen phosphate (phosphate ion concentration) Initial value: 25 ppm).

3-3 is a graph comparing the temporal changes of the phosphate ion concentration in the case where the hydrotalcite-type particles obtained in Example 11 and Reference Example 1 are respectively adsorbed with potassium hydrogen phosphate (phosphate ion concentration) Initial value: 5 ppm).

Fig. 4 is a graph showing the temporal change of the ammonia concentration in the case where the hydrotalcite-type particles obtained in Example 11, the comparative example 12, and the reference example 1 were adsorbed with ammonia gas, respectively.

Fig. 5-1 is a graph showing the results of differential heat measurement of the hydrotalcite-type particles obtained in Example 11 and Reference Example 1.

Fig. 5-2 is a graph showing the results of thermogravimetric measurement of the hydrotalcite-type particles obtained in Example 11 and Reference Example 1.

In the following, the preferred embodiments of the present invention are specifically described, but the present invention is not limited to the following description, and can be appropriately modified and applied without departing from the spirit and scope of the invention.

[Production method]

The production method of the present invention comprises the following steps (I) and (II): Step (I): using at least one selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table, and an aluminum compound as a raw material And obtaining the precursor; step (II): maintaining the precursor in an environment of a temperature of 75 to 150 ° C and a relative humidity of 75 to 100% RH. Further, other operations such as pulverization, classification, washing, hydrothermal, aging, calcination, replacement of interlayer ions, surface coating, and the like may be contained as needed, and other operations are not particularly limited.

Hereinafter, each step will be further described.

<Step (I)>

Step (I) is a step of obtaining a precursor having a half-height width of the peak of the (003) plane of 0.4 or more. In the step (I), the crystallization of the hydrotalcite is inhibited to produce a precursor in a low crystalline state, and the precursor is supplied to the step (II). Therefore, in the step (II), the crystal growth of the plate-like particles is promoted. The plate-like hydrotalcite-type particles of the present invention can be obtained easily and simply. Further, the precursor obtained in the step (I) sometimes contains hydrotalcite-type particles.

In the above step (I), at least one selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table, and an aluminum compound are used as the raw materials. The compound containing a Group 2 element of the periodic table is not particularly limited, and examples thereof include compounds containing magnesium, calcium, barium, and the like. Among them, in the case where hydrotalcite-type particles are used as the acid neutralizing agent, a compound containing magnesium (also referred to as a magnesium compound) is preferred.

From the viewpoint of facilitating the production, the above raw material is preferably a salt which is water-soluble or a salt which is soluble in water containing an acid. Specifically, the zinc compound is preferably selected from the group consisting of hydrogen peroxide At least one of the group consisting of zinc, zinc oxide, basic zinc carbonate, and zinc sulfate, and the compound containing the element of Group 2 of the periodic table is preferably a hydroxide selected from the group 2 element of the periodic table (magnesium hydroxide, etc.) At least one of a group consisting of an oxide (magnesium oxide, etc.) and an alkali carbonate (alkaline magnesium carbonate, etc.), and the aluminum compound is preferably selected from the group consisting of aluminum hydroxide, aluminum oxide, and aluminum sulfate. At least one of them. By using these raw materials, plate-shaped hydrotalcite-type particles can be easily and easily obtained. For example, a solution obtained by dissolving an aluminum compound in a solvent described later and a solution obtained by dissolving at least one selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table in a solvent described later may be separately prepared, and then Further, at least one selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table and an aluminum compound may be dissolved in a solvent to be described later. In this case, each compound does not need to be completely dissolved, and a part of the compound does not dissolve and remains, and it is in a state of a slurry. The solution or slurry prepared by mixing is maintained at a specific temperature as needed, and stirred for a specific period of time, whereby a precursor can be obtained. The temperature and the stirring time are not limited. From the viewpoint of matching the size and shape of the particles, it is preferred to set the holding temperature to 20 ° C to 80 ° C and the stirring time to 5 to 300 minutes.

The raw material may be previously pulverized by a known dry or wet pulverization method such as a hammer mill, a jet mill, a bead mill, or a pulverizer (Fritsch Mill), and then supplied to the step (I).

The amount of the raw material to be used is preferably adjusted so that the obtained plate-like hydrotalcite-type particles satisfy the formula (1) described later. For example, it is preferable that the total amount of at least one compound selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table is converted to the amount of aluminum in an amount of 1 mol per mol of the aluminum compound. It counts 1.5 to 4 moles. Thereby, the crystal structure of the obtained plate-like hydrotalcite-type particles is stable. Even more stable From the viewpoint of characterization, it is more preferable to adjust the total amount of at least one compound selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table in a range of 1.5 to 3 moles in terms of a metal element. Further preferably 2 moles.

As the above raw material, it is particularly preferable to use at least a zinc compound and an aluminum compound. In this way, since the alkalinity generated by the Group 2 element of the periodic table such as magnesium is lowered, the plate-like hydrotalcite-type particles which are less irritating to the skin can be provided. It is especially preferred to not use a compound containing a Group 2 element of the periodic table.

In the above step (I), it is preferred to neutralize the above raw materials using an alkaline component. By performing this neutralization, a precursor can be preferably obtained. The neutralization is preferably carried out by mixing the raw material and the alkaline component so that the pH of the mixed solution of the raw material and the alkaline component is 7 or more. In this case, it may be carried out in the presence of a solvent to be described later. More preferably, the neutralization reaction is carried out so that the pH of the mixed solution of the raw material and the alkaline component is 7.5 or more. In this case, the alkaline component may be dissolved in water and added to a solution or slurry containing at least one of the above-described aluminum compound and a group selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table, and mixed. The alkaline component can also be directly mixed in the form of a powder.

The basic component is not particularly limited, and examples thereof include an alkali metal salt and the like, and one type or two or more types may be used. The alkali metal salt is, for example, a salt of an alkali metal such as lithium, sodium or potassium. Examples of the salt include a hydroxide, a carbonate, a hydrogencarbonate, a decanoate, an aluminate, and an organic amine salt. Among them, sodium hydroxide, sodium carbonate, sodium hydrogencarbonate or the like is preferred.

The solvent is not particularly limited, and examples thereof include water, an organic solvent, and a mixture thereof, and one type or two or more types may be used. Examples of the organic solvent include alcohol, acetone, dimethyl hydrazine, dimethylformamide, tetrahydrofuran, and Examples of the alcohol include a monohydric water-soluble alcohol such as methanol, ethanol or propanol; and a water-soluble alcohol of two or more types such as ethylene glycol and glycerin. As the solvent, water is preferred, and ion-exchanged water is more preferred.

Here, when the carbonate is not used as a raw material, or when the produced particles do not satisfy the following formula (1) even if a carbonate is used, carbon dioxide may be additionally used. Carbon dioxide can be used in any operation as long as it is in step (I).

a solution or slurry containing at least one of the above-mentioned aluminum compound and a group selected from the group consisting of a zinc compound and a compound containing a Group 2 element of the periodic table, or the above-mentioned aluminum compound and selected from the zinc compound and the second table of the periodic table The solution or slurry of at least one of the group consisting of the compound elements of the group element is neutralized, and the resultant can be kept at a specific temperature and stirred for a specific period of time. The temperature and the stirring time are not limited. From the viewpoint of matching the size and shape of the particles, it is preferred to set the holding temperature to 20 ° C to 80 ° C and the stirring time to 5 to 300 minutes.

Further, in the above step (I), in the case where a solvent is used in the above neutralization, the obtained slurry is preferably dried. The drying may be carried out by removing the solvent from the slurry, and the drying means is not particularly limited. For example, vacuum drying, heat drying, etc. are mentioned. Further, the slurry may be directly dried, or may be filtered, washed with water, and then dried. In the case where it is filtered and washed with water and then dried, it is preferred to temporarily prepare the slurry and then dry it by spray drying.

It is preferred to carry out pulverization after the above drying. That is, the above step (I) preferably comprises: neutralizing the raw material in the presence of a solvent, drying the slurry obtained by the neutralization, and pulverizing the dried product. The pulverization method and the pulverization conditions are not particularly limited, and for example, it can be carried out using a ball mill, a Raikai mixer, a Force Mill, a hammer mill, a jet mill or the like.

The precursor obtained in the above step (I) may be in the form of a wet cake (for example, a solid content of 15% by mass or more after drying at 105 ° C for 18 hours), or may be in the form of a powder. It is preferably in the form of a powder. When the powdery precursor is supplied to the step (II), the crystal growth to the plate-like particles can be further promoted in the step (II), and excessive aggregation of the primary particles can be suppressed, which is preferable.

In the case where the precursor obtained in the above step (I) is in the form of powder (powder), it is preferred that the amount of the solid content measured by the above method is 85% by weight or more, more preferably 95% by weight or more. .

The above-mentioned precursor is derived from the half-height width of the peak of the (003) plane to be 0.4 or more. If it is a precursor of a high crystalline state which does not have a full width at half maximum, even if it is supplied to the step (II), the plate shape is not sufficiently formed, so that a plate-like hydrotalcite type particle excellent in slidability cannot be obtained. . The half-height width of the peak derived from the (003) plane of the precursor is preferably 0.5 or more, more preferably 0.6 or more, still more preferably 0.7 or more. Further, the upper limit is preferably 3 or less. More preferably, it is 2 or less, More preferably, it is 1.2 or less.

Further, it is preferable that the precursor has a half-height width of 0.4 or more from the peak of the (006) plane. It is more preferably 0.5 or more, further preferably 0.6 or more, and particularly preferably 0.7 or more. Further, the upper limit is preferably 3 or less. More preferably, it is 2 or less, More preferably, it is 1 or less.

In the present specification, the full width at half maximum can be obtained by an X-ray diffraction method. Specifically, it is obtained by the method described in the examples described later.

The above precursor is further preferably a specific surface area of more than 20 m ² /g and 300 m ² /g or less. By supplying such a precursor to the step (II), the strength or slidability of the obtained plate-like hydrotalcite-type particles and the feeling of application to the skin when it is contained in the cosmetic are better. More preferably, it is 25 m ² /g or more, and further preferably 30 m ² /g or more. The upper limit of the specific surface area is more preferably 250 m ² /g or less.

<Step (II)>

The step (II) is a step of maintaining the precursor obtained in the above step (I) in an environment of a temperature of 75 to 150 ° C and a relative humidity of 75 to 100% RH (also referred to as a "wet environment step"). In the manufacturing method of the present invention, unlike the reaction step under the hydrothermal or atmospheric pressure as in the conventional method, the plate-like water can be obtained by a simple means by merely maintaining the precursor in a high-temperature and high-humidity environment. Talc type particles, therefore, special equipment such as a pressure vessel can be eliminated. That is, the manufacturing equipment can be simplified.

The above step (II) is to maintain the precursor at a temperature of 75 to 150 ° C. From the viewpoint of promoting slab formation, the temperature is preferably 76 ° C or higher, more preferably 78 ° C or higher, and still more preferably 80 ° C or higher. Further, from the viewpoint of manufacturing cost or equipment specifications, it is preferably 95 ° C or lower.

In the present specification, the holding temperature of the step (II) means that the highest temperature in the step is reached.

Further, since the change in temperature may change the crystal growth of the plate-like particles, it is preferable to set the difference between the upper limit and the lower limit of the temperature during the holding process to 10 ° C or lower.

Further, the above step (II) is carried out in an environment having a relative humidity of 75 to 100% RH. From the viewpoint of promoting slab formation, the relative humidity is preferably 76% RH or more, more preferably 77% RH or more, further preferably 78% RH or more, and particularly preferably 79% RH or more, and most preferably 80%. More than %RH. Further, from the viewpoint of the production cost or the equipment specification, it is preferably 95% RH or less, more preferably 90% RH or less.

In the present specification, the relative humidity of the step (II) means the highest limit humidity in the step.

Further, since the change in the relative humidity may change the crystal growth of the plate-like particles, it is preferable to set the difference between the upper limit and the lower limit of the humidity during the holding process to 10% or less.

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

[Plate-like hydrotalcite-type particles]

The production method of the present invention is preferably a method of producing a plate-like hydrotalcite type particle represented by the following formula (1), (R) _1-x (Al) _x (OH) ₂ (A ^n- ) _{x / n} ‧ mH ₂ O (1)

Wherein R represents at least one element selected from the group consisting of a zinc element and a Group 2 element of the periodic table; A ^n- represents an interlayer anion of n valence; x and n respectively satisfy 0.2 ≦ x ≦ 0.4, 1 The number of conditions of ≦n≦4; m is a number of 0 or more). Such a plate-like hydrotalcite-type particle is excellent in slidability and can be used for various uses such as cosmetics.

In the above formula (1), the n-valent interlayer anion is not particularly limited, and from the viewpoint of reduction in reactivity and environmental load, it is preferably selected from hydroxide ions (OH ^- ) and carbonate ions (CO). At least one of the group consisting of ₃ ^2- ) and sulfate ion (SO ₄ ^2- ). Among them, carbonate ions are preferred.

R represents the Group 2 element of the periodic table. For example, magnesium (Mg), calcium (Ca), barium (Ba), etc. are mentioned. Among them, in the case where hydrotalcite-type particles are used as the acid neutralizing agent, magnesium is preferred.

x is a number satisfying 0.2 ≦ x ≦ 0.4, and if it is in this range, the crystal structure is stable. From the viewpoint of further improving the stability, it is preferable to adjust x by [(1-x)/x] being 1.5/1 to 3/1. It is better to adjust by 2/1. That view In terms of point, x is preferably 0.25 or more, more preferably 0.3 or more, and further preferably 0.35 or less. Especially good is 1/3 (= about 0.33).

R represents at least one element selected from the group consisting of a zinc element and a Group 2 element of the periodic table. In the case where a plurality of elements selected from the group consisting of a zinc element and a group 2 element of the periodic table are selected as R, a zinc element and a magnesium element are preferable. In this case, the molar ratio [Zn(mol)/Mg(mol)] of the zinc element to the magnesium element is preferably 0.1 or more. More preferably, it is 0.45 or more, further preferably 0.5 or more, and particularly preferably 0.7 or more. The upper limit is preferably 100.

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

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

In the present invention, it is particularly preferred that in the above formula (1), x and n are each a condition satisfying an integer of 0.30≦x≦0.35 and 1≦n≦3, respectively, and A ^n- is a carbonate ion (CO ₃ ^{2 ). -} ). In this way, the crystal shape is more stable, and therefore, a plate-like hydrotalcite type which can provide a stable and excellent slidability or a good touch feeling to the skin when it is contained in a cosmetic material, and further reduce the irritation to the skin can be obtained. particle.

The plate-like hydrotalcite-type particles are preferably plate-like particles represented by the following formula (2), (Zn) _0.67 (Al) _0.33 (OH) ₂ (CO ₃ ^2- ) _0.165 ‧ mH ₂ O

The crystal structure of this structure is extremely stable, and it is a plate-like hydrotalcite type particle which is excellent in slidability and the touch feeling on the skin when it is contained in a cosmetic, and the irritation to the skin is sufficiently reduced. The The structure can be confirmed according to JCPDS card 00-048-1023.

The average plate surface diameter of the above plate-shaped hydrotalcite-type particles is preferably from 150 to 800 nm. When the average sheet surface diameter is within this range, the fluidity of the powder containing the particles is stabilized, so that it is easy to handle during measurement or packaging, and the touch or slidability to the skin is also contained in the cosmetic. Excellent. It is more preferably 180 nm or more, further preferably 190 nm or more, particularly preferably 300 nm or more, more preferably 500 nm or less, still more preferably 470 nm or less.

The aspect ratio (average plate diameter/average thickness) of the plate-like hydrotalcite-type particles is preferably 4.0 to 20.0. When the aspect ratio is within this range, the fluidity of the powder containing particles is stable, so that it is easy to handle at the time of measurement or packaging, and it is excellent in the touch or slidability to the skin when it is contained in a cosmetic. By. More preferably, it is 4.5 to 15.0, and further preferably 5.0 to 10.0. Among them, the average value (i.e., the average value of the aspect ratio) at the time of operation for obtaining the aspect ratio based on the average plate surface diameter and the average thickness is preferably 4.0 to 20.0. More preferably, it is 4.5 to 15.0, and further preferably 5.0 to 10.0.

In the present specification, the average plate diameter and the average thickness are values calculated based on a scanning electron microscope photograph. Specifically, it can be obtained by the method described in the examples below.

Here, the plate-like hydrotalcite-type particles obtained by the production method of the present invention have a plate-like characteristic, and preferably have the above-described characteristics of a fixed aspect ratio, and also have a particle shape and an aspect ratio. Features with less deviation. In order to enhance or maintain the touch or slidability to the skin when it is contained in the cosmetic, it is preferred that the ratio of the aspect ratio measured when the width ratio is measured is less than 4.0 or exceeds 20.0 three times. the following. Further, it is preferable that the coefficient of variation of the standard deviation calculated when measuring the average plate surface diameter and the average thickness is 0.5 or less. More preferably 0.4 or less.

The plate-like hydrotalcite-type particles preferably have a pH (also referred to as "pigment pH") of 6.0 to 8.5 by a pigment test method of JIS K5101-17-1 (2004). When the pH of the pigment is within this range, the irritation to the skin is sufficiently lowered, so that it is particularly useful for use in direct contact with the skin such as a cosmetic. The pH of the pigment is preferably from 7.0 to 8.4, more preferably from 7.2 to 8.2.

In the present specification, the pigment pH is a measured value obtained by a pigment test method of JIS K5101-17-1 (2004). Specifically, it can be obtained by the method described in the examples below.

The above plate-shaped hydrotalcite-type particles preferably have a specific surface area of 0.1 to 50 m ² /g. When the specific surface area is in this range, it is more excellent in strength, slidability, and a feeling of application to the skin when it is contained in a cosmetic. More preferably, it is 5 to 40 m ² /g, and further preferably 10 to 20 m ² /g.

In the present specification, the specific surface area (also referred to as SSA) means a BET specific surface area.

The BET specific surface area refers to a specific surface area obtained by the BET method which is one of the methods for measuring the specific surface area. The specific surface area refers to the surface area per unit mass of an object.

The BET method is a gas adsorption method in which gas particles such as nitrogen are adsorbed to solid particles and the specific surface area is measured in accordance with the amount adsorbed. Specifically, the specific surface area is determined by determining the single molecule adsorption amount VM by the BET equation based on the relationship between the pressure P and the adsorption amount V. The detailed measurement method of the specific surface area in the present specification will be described in the examples to be described later.

The plate-like hydrotalcite-type particles preferably have a ratio of D ₉₀ to D ₁₀ (D ₉₀ /D ₁₀ ) which is an index of the steepness of the volume-based particle size distribution of 2 to 150. When D ₉₀ /D _{10 is} in this range, the particle diameter variation is small, and the fluidity of the powder containing particles is stable. Therefore, it is easy to handle at the time of measurement or packaging, and it is excellent in the touch feeling or slidability to the skin when it is contained in a cosmetics. When the value of D ₉₀ /D ₁₀ is increased, there is a tendency that the touch feeling on the skin is increased when it is contained in the cosmetic. Therefore, the value of D ₉₀ /D ₁₀ is more preferably 10 or more, still more preferably 30 or more. Further, ₉₀ / D ₁₀ D greater, means that the particle size distribution is broad, the smaller the value, the steeper the mean particle size distribution.

In the present specification, D ₁₀ means a 10% cumulative particle diameter on a volume basis, and D ₉₀ means a 90% cumulative particle diameter on a volume basis. D ₁₀ and D ₉₀ are values obtained by measuring the particle size distribution, respectively. Specifically, it can be obtained by the method described in the examples below.

The plate-like hydrotalcite-type particles preferably have a secondary particle median diameter (D ₅₀ ) of from 1 to 200 μm. When the median diameter (D ₅₀ ) is in this range, the fluidity of the powder containing particles is stable, so that it is easy to handle during measurement or packaging, and it is a touch feeling to the skin when it is contained in a cosmetic or Slidability is also excellent.

In the present specification, the median diameter (D ₅₀ ) means 50% cumulative particle diameter on a volume basis, which means that when the powder is divided into two parts from a certain particle size, the larger side and the smaller one are smaller. The side becomes the same diameter. Specifically, it can be obtained by the method described in the examples below.

Further, the plate-shaped hydrotalcite-type particles may be partially or entirely coated with a surface coating agent as long as it does not impair the range of good touch applied to the skin when it is contained in the cosmetic. As the surface coating agent, any of an inorganic compound and an organic compound can be preferably used. The inorganic compound is not particularly limited, and examples thereof include oxides, hydroxides, sulfates, and carbonates of barium, calcium, strontium, barium, aluminum, zirconium, cerium, and zinc. The organic compound is not particularly limited, and examples thereof include polyasoxy oil, fatty acid and metal salt thereof, alkyl decane, alkoxy decane, decane coupling agent, titanium coupling agent, aluminum coupling agent, amino acid, and nylon. Carbomer and its metal salts, polyacrylic acid, trimethylpropanol, triethylamine, higher alcohols, and the like.

Among the above surface coating agents, a compound containing a ruthenium atom (also referred to as a ruthenium compound) is preferred. That is, the plate-like hydrotalcite-type particles are preferably partially or wholly coated with a ruthenium compound, and the production method of the present invention preferably further comprises, in addition to the steps (I) and (II), a surface coated with a ruthenium compound. Part or all of step (III). Thereby, it is possible to suppress excessive dissolution of zinc ions and to reduce irritation to the skin, thereby exhibiting a moderate astringent effect, and further improving compatibility with a resin or a solvent, and also improving water repellency, so that not only cosmetics Further, it is a more useful plate-shaped hydrotalcite-type particle in various applications such as an additive in a resin. As the cerium compound, more preferred is cerium oxide.

The method of coating the surface of the plate-like hydrotalcite-type particles with the above surface coating agent is not particularly limited. For example, when cerium oxide is used, a method of adding sodium citrate and an acid to neutralize a slurry containing plate-like hydrotalcite-type particles may be mentioned. The amount of the surface coating is not particularly limited. For example, it is preferably 100% by mass based on the total amount of the plate-like hydrotalcite-type particles, and the proportion of the surface coating agent such as cerium oxide is 0.001 to 30% by mass. More preferably 5 to 25% by mass.

The plate-like hydrotalcite-type particles preferably have an oil absorption of 20 to 300 mL/100 g. When the oil absorption amount is within this range, the degreasing effect of the skin can be appropriately obtained, so that the skin is not irritated and it is more practical as a raw material for cosmetics. More preferably 25~200mL/100g.

In the present specification, the oil absorption amount can be determined by the method described in the examples below.

The plate-like hydrotalcite-type particles preferably have a pore volume of from 0.01 to 1.0 cm ³ /g by the BJH method. When the pore volume is 0.01 cm ³ /g or more, the porosity of the particles themselves is improved, so that the oil absorption property of the pores inside the particles is sufficient, and since the particles themselves are moderately weighted, they are in contact with the particle powder. The refreshing sensation, uniform ductility, and smoothness of the sense of smoothness are further enhanced. On the other hand, when it is 1.0 cm ³ /g or less, the porosity of the particles itself is moderate, and the particle strength is sufficient, and the particle disintegration is sufficiently suppressed when the cosmetic containing the hydrotalcite particles is applied to the skin. The sustainability of the smoothness of the results is further improved. More preferably, it is 0.02 to 0.5 cm ³ /g.

In the present specification, the pore volume can be obtained by a BJH (Barrett-Joyner-Halenda) method. Specifically, it can be obtained by the method described in the examples below.

The plate-like hydrotalcite-type particles are also excellent in adsorption performance of ammonia gas or a phosphorus compound. Therefore, it can also be preferably used for such adsorbent applications. In particular, the plate-like hydrotalcite-type particles obtained by the present invention are excellent in the adsorption performance of the phosphorus compound contained in the treatment water discharged from the garbage disposal site or the primary treatment water discharged from the purification tank such as the sewage treatment plant. Adsorbents are extremely useful.

[use]

The plate-like hydrotalcite-type particles obtained by the production method of the present invention are excellent in slidability, and are excellent in adsorption performance of ammonia gas or a phosphorus compound. Therefore, it can be used for various uses such as cosmetics, pharmaceuticals, quasi-drugs, adsorbents, catalysts, additives for resins, acid neutralizers, and the like. Among them, it is particularly useful as a raw material for cosmetics, and a cosmetic containing the above-described plate-shaped hydrotalcite-type particles is one of the inventions.

Since the cosmetic material contains the plate-like hydrotalcite-type particles obtained by the production method of the present invention, it is excellent in sliding feeling when it is slidably contained in the cosmetic material, and can also be expected to have a soft focus effect or a sebum adsorption effect. . Therefore, it is especially suitable for the recent market demand. The cosmetic is not particularly limited, and examples thereof include a powder cake, a makeup foundation, a sunscreen, an eye shadow, a blush, a mascara, a lipstick, an antiperspirant, and a degreased paper. Among them, it is especially suitable for powder cakes.

Moreover, the above-mentioned cosmetic material may also be used in addition to the platy hydrotalcite type particles of the present invention. In addition to one or more other components. The other components are not particularly limited. For example, in addition to the organic solvent or the dispersing agent, any aqueous component or oil component which is generally used in the field of cosmetics can be mentioned. Specific examples thereof include: oil; surfactant; humectant; higher alcohol; metal ion blocker; various polymers (natural, semi-synthetic, synthetic or inorganic water-soluble or oil-soluble polymer); Other pharmaceutical ingredients; various extracts; inorganic and organic pigments; various powders such as inorganic and organic clay minerals; inorganic and organic pigments treated by metal soap or polyfluorene; colorants such as organic dyes; preservatives; Oxidizing agent; pigment; tackifier; pH adjuster; perfume; cold feel agent; astringent; fungicide; skin activator. The content of the components is not particularly limited as long as it does not impair the effects of the present invention.

[Examples]

In order to explain the present invention in detail, the following examples are given, but the invention is not limited to the embodiments. Unless otherwise stated, "%" means "% by weight (% by mass)".

Example 1

(1) Neutralization

96.6 g of zinc sulfate heptahydrate and 81.2 mL of an aqueous solution of 354 g/L of aluminum sulfate (28.7 g in terms of Al ₂ (SO ₄ ) ₃ ) were mixed, and ion-exchanged water was added in a total amount of 350 mL to obtain a metal. Salt mixed aqueous solution. Further, 46.7 mL of a 720 g/L sodium hydroxide aqueous solution and 26.7 g of sodium carbonate were mixed, and ion-exchanged water was added in such a manner that the total amount was 350 mL to obtain an alkaline mixed aqueous solution. 50 mL of ion-exchanged water was placed in a 1 L round bottom flask, and the aqueous solutions were added with stirring. The pH of the slurry at this time was 9. Then, it was stirred at 50 ° C for 30 minutes, thereby obtaining a slurry.

(2) Drying and smashing

The slurry obtained by the above "(1) Neutralization" was filtered and washed with water until the conductivity of the washing liquid became 100 μS/cm or less. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL CORPORATION, FM-1) for 20 seconds, whereby a powder of a hydrotalcite precursor was obtained.

(5) Wet environment steps

1 g of the powder obtained by the above "(2) Drying and pulverization" was placed in a glass petri dish having an inner diameter of 27 mm and a height of 15 mm, and placed in a constant temperature and humidity device (PR-1KT, manufactured by ESPEC). It was adjusted from room temperature to 85 ° C, relative humidity 85% RH over 15 minutes, and maintained at 85 ° C, relative humidity 85% RH for 3 hours, then the heater was turned off and cooled to room temperature. Again, this step is carried out in the atmosphere. A powder (1) containing hydrotalcite-type particles was thus obtained.

Example 2~6

In the first embodiment, the powder containing the hydrotalcite-type particles was obtained in the same manner as in Example 1 except that the holding time in the "(5) Wet environment step" was changed as shown in Table 1. 2)~(6).

Example 7~11

In Example 1, the reaction time in "(1) Neutralization" (that is, the stirring time at 50 ° C) was set to 10 minutes, and the holding time in "(5) Wet Environment Step" is as shown in Table 1. Powders (7) to (11) containing hydrotalcite-type particles were obtained in the same manner as in Example 1 except that the change was carried out in the same manner as in the above.

Example 12

Filtration of the hydrotalcite precursor slurry obtained in "(1) Neutralization" of Example 10, The water was washed until the conductivity of the washing liquid became 100 μS/cm or less. When the obtained filter cake 3.3 g (solid content component 30%) was supplied to "(5) Wet environment step", it was set as Table 1. A powder (12) containing hydrotalcite-type particles was thus obtained.

Example 13~18

In the first embodiment, the Zn raw material used in "(1) Neutralization" was changed to the Zn raw material and the Mg raw material shown in Table 1, and the holding time in the "(5) Wet environment step" is shown in Table 1. Powders (13) to (18) containing hydrotalcite-type particles were obtained in the same manner as in Example 1 except that the change was carried out as described above.

Example 19, 20

(3) ripening

The slurry obtained by "(1) Neutralization" was placed in a 1 L round bottom flask in a manner of 42 g in terms of the solid content in the slurry, and the total amount was 600 mL. Ion-exchanged water was added, followed by stirring at 50 ° C for 22 hours. The slurry was filtered and washed with water until the conductivity of the washing liquid became 100 μS/cm or less. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL CORPORATION, FM-1) for 20 seconds, whereby a powder of a hydrotalcite precursor was obtained. 1 g of the obtained powder was supplied to "(5) Wet environment step" of Example 1 (wherein the holding time was changed as described in Table 1). Powders (19) and (20) containing hydrotalcite-type particles were obtained in this manner.

Example 21

(1) Neutralization

136.2 mL (40.5 g of MgSO ₄ ) of 297 g/L of magnesium sulfate heptahydrate was mixed with 81.2 mL (28.7 g of Al ₂ (SO ₄ ) ₃ ) of 354 g/L of aluminum sulfate aqueous solution, and Ion-exchanged water was added in such a manner that the total amount became 350 mL, and a mixed aqueous solution of a metal salt was obtained. Further, 46.7 mL of a 720 g/L sodium hydroxide aqueous solution and 26.7 g of sodium carbonate were mixed, and ion-exchanged water was added in such a manner that the total amount was 350 mL to obtain an alkaline mixed aqueous solution. 50 mL of ion-exchanged water was placed in a 1 L round bottom flask, and the aqueous solutions were added with stirring. The pH of the slurry at this time was 9. Then, the mixture was stirred at 50 ° C for 30 minutes, whereby a slurry of the hydrotalcite precursor was obtained.

(5) Wet environment steps

The slurry of the hydrotalcite precursor obtained in the above "(1) Neutralization" was filtered and washed with water until the conductivity of the washing liquid became 100 μS/cm or less. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL CORPORATION, FM-1) for 20 seconds, whereby a powder of a hydrotalcite precursor was obtained. 1 g of the obtained powder was placed in a glass petri dish having an inner diameter of 27 mm and a height of 15 mm, and placed in an unsaturated type highly accelerated life test apparatus (manufactured by Hirayama Seisakusho Co., Ltd., HASTEST PC-242HSR2) for 80 minutes from the room. The temperature was adjusted to 120 ° C, relative humidity 85% RH, and maintained at 120 ° C, relative humidity 85% RH for 168 hours, then the heater was turned off and cooled to room temperature. Again, this step is carried out in the atmosphere. A powder (21) containing hydrotalcite-type particles was thus obtained.

Comparative example 1

In the first embodiment, a powder (c1) containing hydrotalcite-type particles was obtained in the same manner as in Example 1 except that the "(5) wet environment step" was not carried out.

Comparative example 2~5

In the first embodiment, the temperature, the relative humidity, and the holding time in the "(5) Wet environment step" were changed as shown in Table 2, and otherwise obtained in the same manner as in Example 1. A powder (c2) to (c5) containing hydrotalcite-type particles is obtained.

Comparative Example 6

(4) Water heat

The slurry obtained by "(1) Neutralization of Example 1 was weighed into a 100 mL pressure vessel in a manner of 5.3 g in terms of solid content in the slurry, and the total amount was 75 mL. Ion-exchanged water was added in a manner, and then kept at 180 ° C for 2 hours. The slurry was filtered and washed with water until the conductivity of the washing liquid became 100 μS/cm or less, whereby a cake was obtained. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL Co., FM-1) for 20 seconds, thereby obtaining a powder (c6), but Most of them were zinc oxide, and thus the evaluation described later was not performed.

Comparative Example 7

(1) Neutralization

96.6 g of zinc sulfate heptahydrate and 81.2 mL of an aqueous solution of 354 g/L of aluminum sulfate (28.7 g in terms of Al ₂ (SO ₄ ) ₃ ) were mixed, and ion-exchanged water was added in such a manner that the total amount became 350 mL to obtain a metal salt. Mix the aqueous solution. Further, 46.7 mL of a 720 g/L sodium hydroxide aqueous solution and 26.7 g of sodium carbonate were mixed, and ion-exchanged water was added in such a manner that the total amount was 350 mL to obtain an alkaline mixed aqueous solution. 50 mL of ion-exchanged water was placed in a 1 L round bottom flask, and the aqueous solutions were added with stirring. The pH of the slurry at this time was 9. Then, it was stirred at 50 ° C for 10 minutes, whereby a slurry was obtained.

(3) ripening

The slurry obtained by "(1) Neutralization" was weighed into a 1 L round bottom flask in such a manner that the solid content in the slurry was 42 g, and the total amount was 600 mL. The ion-exchanged water was introduced, and then stirred at 50 ° C for 22 hours. The slurry was filtered and washed with water until the conductivity of the washing liquid became 100 μS/cm or less. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL CORPORATION, FM-1) for 20 seconds, thereby obtaining a powder containing hydrotalcite-type particles. (c7).

Comparative Example 8

In the same manner as in Example 7, a powder (c8) containing hydrotalcite-type particles was obtained in the same manner as in Example 7 except that the "(5) wet environment step" was not carried out.

Comparative Example 9

In the same manner as in Comparative Example 7, the filter cake of the hydrotalcite precursor was obtained in the same manner as in Comparative Example 7, except that the aging temperature (50 ° C) in "(3) aging was changed to 85 ° C. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL CORPORATION, FM-1) for 20 seconds, whereby a hydrotalcite powder was obtained. A powder (c9) containing hydrotalcite-type particles was thus obtained.

Comparative Examples 10, 11

1 g of the hydrotalcite powder obtained in "(3) aging" of Comparative Example 9 was supplied to "(5) Wet environment step" of Example 1 (wherein the holding time was changed as shown in Table 2) . Powders (c10) and (c11) containing hydrotalcite-type particles were obtained in this manner.

Comparative Example 12

In the same manner as in Comparative Example 7, the filter cake of the hydrotalcite precursor was obtained in the same manner as in Comparative Example 7, except that the aging temperature (50 ° C) in "(3) aging was changed to 100 ° C. The obtained cake was dried at a temperature of 105 ° C for 18 hours, and 5 g of the dried powder was pulverized by a strong pulverizer (manufactured by OSAKA CHEMICAL Co., FM-1) for 20 seconds, thereby obtaining a water-slip Powder of stone particles (c12).

Comparative Example 13

In the same manner as in Example 13, except that the "(5) wet environment step" was carried out, a powder (c13) containing hydrotalcite-type particles was obtained.

Comparative Example 14

In the same manner as in Example 13, except that the relative humidity in the (5) wet environment step was changed as described in Table 2, a powder containing hydrotalcite-type particles was obtained (c14). ).

Comparative Example 15

In the same manner as in Example 16, except that the "(5) wet environment step" was carried out, a powder (c15) containing hydrotalcite-type particles was obtained.

Comparative Example 16

In the same manner as in Example 16, except that the relative humidity in the (5) wet environment step was changed as described in Table 2, a powder containing hydrotalcite-type particles was obtained (c16). ).

Comparative Example 17

In the same manner as in Example 21, a powder (c17) containing hydrotalcite-type particles was obtained in the same manner as in Example 21 except that the "(5) wet environment step" was not carried out.

Reference example 1

For reference, it will be used as a commercially available hydrotalcite compound (STABIACE‧HT-1-NC: (Mg) _0.67 (Al) _0.33 (OH) ₂ (CO ₃ ^2- ) _0.17 ‧0.5H ₂ O, 堺Chemical Industry The product manufactured by the company was designated as the powder of Reference Example 1 (the hydrotalcite-type particles obtained in Reference Example 1).

The hydrotalcite-type particles (powder) obtained in each of the examples and the comparative examples, and the precursors in the "(5) wet environment step" (when the "(5) wet environment step" is not performed) The product was measured and evaluated separately according to the following methods.

1. Measurement of full width at half maximum

For each of the obtained powders, a powder X-ray diffraction pattern (also simply referred to as an X-ray diffraction pattern) was measured under the following conditions. For example, the X-ray diffraction pattern of the powder obtained in Example 11 is shown in Fig. 1. Then, the half widths of (003) and (006) were measured based on the diffraction pattern obtained by the measurement of the X-ray diffraction of each of the obtained powders. The results are shown in Tables 3 and 4.

- Analysis conditions -

Using the machine: RMIT-UltimaIII

Radioactive source: CuKα

Voltage: 50kV

Current: 300mA

Sample rotation speed: 60 rpm

Divergence slit: 1.00mm

Longitudinal divergence limiting slit: 10mm

Scattering slit: open

Light receiving slit: open

Scan mode: FT

Counting time: 2.0 seconds

Step width: 0.02.00 °

Operating axis: 2θ / θ

Scan range: 1.6000~70.0000°

Cumulative number: 1 time

The following information is used for the identification of 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

Furthermore, in the X-ray diffraction using the CuKα line as a radiation source, the maximum peak of the hydrotalcite is derived from the peak of the (003) plane at 2θ=11.6°, and the peak derived from the (006) plane is located at 2θ=23.4. ° nearby.

2. Measurement of specific surface area (SSA)

The measurement of the specific surface area (SSA) was carried out under the following conditions. The results are shown in Tables 3 and 4.

Machine used: manufactured by Mountech, Macsorb Model HM-1220

Environment: nitrogen (N ₂ )

Degassing condition of external degassing device: 105 ° C - 15 min

Degassing condition of the body of the specific surface area measuring device: 105 ° C - 5 min

3. Median particle size (D ₅₀ ) and steepness of particle size distribution (D ₉₀ /D ₁₀ )

The particle size distribution measurement was carried out by a laser diffraction-scattering particle size analyzer (manufactured by Horiba, model: LA-950-V2).

First, 60 mL of 0.025 wt% sodium hexametaphosphate aqueous solution was added to 0.1 g of the sample (sample powder), and the intensity was set to V-LEVEL3 for 2 minutes using an ultrasonic homogenizer (US-600, manufactured by Nippon Seiki Co., Ltd.). Dispersion treatment, thereby preparing a suspension of the sample. Then, a 0.025 wt% aqueous solution of sodium hexametaphosphate is circulated in the sample circulator to have a transmittance of 80 to 95%. The above suspension was added dropwise, and ultrasonic dispersion was carried out for 60 seconds at a circulation speed of 5 and a stirring speed of 1, and then measurement was carried out. The results are shown in Tables 3 and 4.

4, elemental analysis

The Mg, Zn, and Al contents in the hydrotalcite can be measured by inductively coupled plasma (ICP) emission spectrometry and measured as follows.

Specifically, as described below, a spectroscope (manufactured by SII Corporation, ICP SPS3100) was used and measurement was carried out by a standard method using 钪 (Sc) as an internal standard element.

First, about 0.2 g of the sample was accurately weighed and placed in a beaker, about 5 mL of hydrochloric acid was added to dissolve it, and it was filled in a 100 mL volumetric flask, and the volume was adjusted by ion-exchanged water. It was diluted 20 times in the Mg content measurement, 50 times in the Zn content measurement, 10 times in the Al content measurement, and the Sc standard solution was added in such a manner that the Sc concentration became 10 ppm, and the obtained solution was used as a test. The liquid was measured according to the following measurement conditions, and the obtained raw materials were calculated by the following calculation conditions, thereby calculating the contents of Mg, Zn, and Al. The results are shown in Tables 3 and 4.

-Measurement conditions -

A calibration curve was prepared using a spectroscope (manufactured by SII Corporation, ICP SPS3100) at wavelengths of 279.55 nm (Mg), 213.86 nn (Zn), 396.15 nm (Al), and 361.49 nm (Sc), and then the sample was measured.

As the concentration of the sample for the calibration curve, use

Mg (ppm) = 50, 40, 30, 20, 10;

Zn (ppm) = 20, 16, 12, 8, 4;

Al (ppm) = 50, 40, 30, 20, 10

5 points each.

Further, any sample for the calibration curve was added with a Sc standard solution so that the concentration of Sc became 10 ppm. The calculation conditions are as follows.

Each content (%) = original data × 100 / sample weight (g) × dilution ratio / 10000

Further, the content of Mg, Zn, and Al (% by weight) obtained as described above was used, and the following formula was calculated: x = (Al content / 26.982) ÷ {(Mg content / 24.305) + (Zn content / 65.38) + (Al content / 26.982)}, and the value corresponding to x in the above formula (1) is obtained. The results are shown in Tables 3 and 4.

5, pore volume

The measurement was performed using an automatic specific surface area/fine pore distribution measuring device (product name "BEL SORP-mini II", manufactured by NIPPON BEL Co., Ltd.). 0.1 g of the sample was filled in the measuring unit, and measurement was performed after degassing treatment at 200 °C.

For the analysis method for calculating the average pore diameter, the total pore volume, and the pore distribution, the BJH method was used.

The average pore diameter means a value obtained by dividing the total pore volume by 4 times the surface area. It assumes that all the pores in the sample are cylindrical, and sets the cylindrical pores to a volume V. At this time, the volume of the cylindrical pores is represented by the following formula (i).

V=πD ² L/4 (i)

In the formula, D is a pore diameter, and L is a length of a cylindrical pore.

Then, the side area A of the cylindrical pores is represented by the following formula (ii).

A=πDL (ii)

According to the above formulas (i) and (ii), the following formula (iii) can be obtained.

D=4V/A (iii)

D calculated by the above formula (iii) is defined as an average pore diameter.

The total pore volume is the cumulative value of the entire range of pores obtained based on the pore distribution results obtained by the BJH method. The results are shown in Tables 3 and 4.

6. Average plate diameter, average thickness and aspect ratio

Electron micrographs were taken for each powder by a field emission type scanning electron microscope (JSM-7000F, manufactured by JEOL Ltd.) to reflect about 50 to 10,000 particles. The average value of the plate surface diameters of the 20 particles on the straight line randomly drawn on the electron microscope photograph was defined as the average plate surface diameter of each of the powders. The average thickness (the average of the thicknesses of 20 particles) was calculated by the same method, and the aspect ratio was determined by (average plate diameter/average thickness). When it is difficult to measure the surface diameter and thickness of the board, it is measured by using an appropriate magnification. The powders photographed in the examples and the comparative examples were replaced one by one, and the operation was repeated 10 times to calculate the average value of the obtained aspect ratios. The results are shown in Tables 3 and 4. Further, for each of the powders obtained in the examples, when calculating the average plate surface diameter and the average thickness, the standard deviation of the average plate surface diameter and the average thickness (the square of the difference between the average value and the average value) was calculated. The square root) and its coefficient of variation (the value obtained by dividing the standard deviation by the average). The results are shown in Table 3.

7, pigment pH

The pigment pH of each powder was measured by the following method according to the pigment test method of "JIS K5101-17-1:2004".

In a glass container with a stopper, 5 g of a sample was placed in 50 g of distilled water, and when the stopper was taken out, the mixture was heated for about 5 minutes to be boiled, and then further boiled for 5 minutes. After boiling, after the plug is placed and cooled to normal temperature, the plug is pulled out, distilled water equivalent to the reduced amount is added, and the plug is again plugged. After shaking for 1 minute, it was allowed to stand for 5 minutes. The plug was removed and the pH was measured using a pH meter. The results are shown in Tables 3 and 4.

8, oil absorption

The oil absorption was measured using isopropyl myristate using the following method in accordance with JIS K5101-13-1 (2004).

About 0.5 g of the sample was accurately weighed and placed on the coated paper, and the sample was placed on the frosted glass portion 10 cm in the center of the glass plate. Isopropyl myristate (referred to as "IPM") was added to the microtiter tube, 0.2 mL of the sample was added dropwise, and the mixture was stirred by a doctor blade. Then, IPM was added every 1 to 2 drops, and the whole was stirred by a doctor blade every time the dropping was performed. Set to the end when the whole is started as a hard putty block.

The oil absorption amount is calculated by the following formula. The results are shown in Tables 3 (and 4).

Oil absorption (ml/100g) = {V (mL) ÷ sample weight (g)} × 100

9, slidability (MIU, MMD)

The slidability evaluation of each sample was carried out by the following method.

The double-sided tape was attached to a glass slide, and a powder (sample) of about half a spoon was placed on the adhesive surface, and the powder was spread by a cosmetic sponge, and a friction element was placed thereon. The slide was moved, and the average friction coefficient MIU and the variation value MMD of the average friction coefficient were measured in accordance with the load applied to the friction member. The measurement was performed by a friction sensor (manufactured by Kato Tech, KES-SE).

As a comparison object, slab-shaped barium sulfate ‧ H (manufactured by Sigma Chemical Industry Co., Ltd.) and STABIACE ‧ -1--1-NC (manufactured by Sigma Chemical Industry Co., Ltd.) as a commercially available hydrotalcite-based compound (Reference Example 1) were used.

The average friction coefficient MIU of the platy barium sulfate ‧H is 0.64, the variation coefficient of the average friction coefficient MMD is 0.0103, the average friction coefficient MIU of STABIACE‧HT-1-NC is 0.897, and the variation value of the average friction coefficient MMD is 0.047.

Furthermore, the smaller the average coefficient of friction coefficient MIU coefficient is, the smaller the index of the powder is, the smaller the value of the coefficient of friction coefficient is, the smaller the value of the MMD coefficient is, the more slippery and the indicator of no roughness. The results are shown in Tables 3 (and 4).

10. Evaluation as a cosmetic (functional evaluation)

(1) First, using a coffee grinder, the hydrotalcite obtained in the examples and the comparative examples was 20.00% by weight, mica (product name: Y-2300X; manufactured by YAMAGUCHI MICA Co., Ltd.) 24.83% by weight, sericite (product name: FSE; manufactured by Sanshin Mining Co., Ltd.) 29.79% by weight, globular polyfluorene (product name: KSP-105; manufactured by Shin-Etsu Chemical Co., Ltd.) 6.44% by weight, titanium oxide (product name: R-3LD; manufactured by Nippon Chemical Industry Co., Ltd.) 7.36% by weight, iron oxide (yellow) (product name: iron oxide yellow; manufactured by PINOA) 1.10% by weight, iron oxide (red) (product name: iron dan; manufactured by PINOA) 0.37 wt%, metal soap (product name) :JPM-100; manufactured by Sigma Chemical Industry Co., Ltd.) 0.92% by weight and oil (product name: KF96; manufactured by Shin-Etsu Chemical Co., Ltd.) 9.20% by weight and stirred for 1 minute and 30 seconds.

Take the obtained powdery mixture 0.8g to a diameter of 20mm The mold was held at a pressure of 200 kgf/cm ² for 30 seconds using a press machine to prepare a powder cake containing hydrotalcite.

(2) In comparison, using a coffee grinder, 31.03 wt% of mica (product name: Y-2300X; manufactured by YAMAGUCHI MICA Co., Ltd.), sericite (product name: FSE; manufactured by Sanshin Mining Co., Ltd.), 37.24 wt%, Spherical polyfluorene (product name: KSP-105; manufactured by Shin-Etsu Chemical Co., Ltd.) 8.05 wt%, titanium oxide (product name: R-3LD; 堺Chemistry Manufactured by the company, 9.20% by weight, iron oxide (yellow) (product name: iron oxide yellow; manufactured by PINOA), 1.38 wt%, iron oxide (red) (product name: iron dan; manufactured by PINOA) 0.46 wt%, metal Soap (product name: JPM-100; manufactured by Daiei Chemical Industry Co., Ltd.) 1.15 wt% and oil (product name: KF96; manufactured by Shin-Etsu Chemical Co., Ltd.) 11.49 wt% was stirred and mixed for 1 minute and 30 seconds.

Take the obtained powdery mixture 0.8g to a diameter of 20mm The mold was prepared by using a press and holding at a pressure of 200 kgf/cm ² for 30 seconds to prepare a powder cake containing no hydrotalcite.

(3) Applying the powder cake obtained in the above (1) and (2) to the 10-person inspector, and applying the feeling to the skin when it is contained in the cosmetic, the inspector selects the following criteria. Evaluation. Furthermore, the test was conducted by blind inspection. The evaluation results are shown in Tables 3 and 4.

(Evaluation criteria for smearing touch)

◎: The powder containing the hydrotalcite of the above (1) was used in comparison with the powder cake containing no hydrotalcite of the above (2), and the touch feeling was good.

○: Both are the same smeared touch.

X: The powder cake containing the hydrotalcite of the above (2) was used, and the touch cake containing the hydrotalcite of the above (1) was used, and the touch feeling was good.

11, SEM image

The shape of the particles was observed using a field emission type scanning electron microscope (manufactured by JEOL Ltd., JSM-7000F). An electron micrograph of the powder obtained in Example 11 is shown in Figs. 2-1 to 2-4.

12. Adsorption rate of phosphorus compounds in aqueous solution

Add 1 g of the sample to 100 g of the solution having the phosphate ion concentration adjusted to 50, 25, and 5 ppm, respectively, using potassium hydrogen phosphate, and stir for a specific period of time, and then filter the phosphate ion concentration of the filtered solution using an ion chromatograph. (Measured by Dionex, model: ICS-2000). The phosphate ion concentration measured with respect to the case of using the powder obtained in Example 11 over time is shown in Figs. 3-1, 3-2 and 3-3. For comparison, in the drawings, the time-dependent phosphate ion concentration in the case of using the powder of Reference Example 1 is described together.

The adsorption rate of the phosphorus compound in the control group after a lapse of one hour was calculated according to the following formula.

Phosphorus compound adsorption rate (%) = 100 × (phosphate ion concentration of the control group after a hour - phosphate ion concentration of the sample (sample) after a hour) / (control group after a hour) Phosphate ion concentration)

Further, the phosphate ion concentration of the control group after a lapse of a hour was stirred with a potassium phosphate, and 100 g of a solution having a phosphate ion concentration of 50, 25, and 5 ppm was stirred for a specific period of time without adding an evaluation sample. The phosphate ion concentration of the filtered solution after a hour. After 1 hour and 2 hours passed, the phosphate ion concentration of the control group after 4 hours passed was 50 ppm, 25 ppm, and 5 ppm, respectively, and was the same value as the initial value.

13, ammonia adsorption rate

1.0 g of each sample powder was placed in a 5 L sampling bag (manufactured by GL Science Co., Ltd.), and a 5 L sampling bag to which a sample was not added as a control group was also prepared. 3 L of nitrogen containing 100 ppm of ammonia was injected into the sampling bag, and immediately sealed, and allowed to stand at 20 ° C and a humidity of 65% for 1 hour. After standing, 100 mL of the gas in the sampling bag was sucked by a suction device, and the concentration of ammonia was measured using a probe tube (No. 3La) manufactured by GASTEC. Will be obtained using Example 11 The change with time in the ammonia concentration in the case of the powder is shown in Fig. 4. For comparison, the temporal change of the ammonia concentration in the case of using the powder obtained in Comparative Example 12 and Reference Example 1 is collectively shown in FIG.

The ammonia gas adsorption rate with respect to the control group was calculated according to the following formula.

Ammonia gas adsorption rate (%) = 100 × (ammonia concentration in the control group - ammonia concentration in the evaluation sample) / (ammonium concentration in the control group)

Further, the ammonia concentration of the control group was measured by adding only a sample bag containing nitrogen gas of 3 ppm of ammonia to 100 L of the test sample without leaving the evaluation sample, and the ammonia concentration was measured after standing for 1 hour. The ammonia concentration of the control group was 100 ppm.

14. Differential heat-heat weight measurement

For the hydrotalcites of Example 11 and Reference Example 1, differential thermal-thermal weight measurement (TG/DTA) was performed. Specifically, differential heat-thermal weight measurement (TG/DTA) was performed according to the following conditions. The measurement results are shown in Figures 5-1 and 5-2.

-Measurement conditions -

Measuring machine: manufactured by Hitachi High-Tech Scientific Co., Ltd., differential heat-thermal weight measuring device (Model: TG/DTA6300)

Heating rate: 10 ° C / min

Measuring temperature range: 30~500°C

Measurement environment: atmosphere 200mL/min

Reference: Al ₂ O ₃

Sample weight: 10.0mg

Sample container: Al

According to the above embodiment, the following cases were confirmed.

Each of Examples 1 to 21 is an example in which slab-shaped hydrotalcite-type particles were produced by the production method of the present invention, and the slidability (MIU, MMD) was remarkably high with respect to the commercially available hydrotalcite powder of Reference Example 1. In particular, the powders obtained in Examples 3, 5, 6, and 11 exhibited substantially the same or higher slidability as the platy barium sulfate ‧H (manufactured by Daimlersei Kogyo Co., Ltd., MIU=0.64, MMD=0.0103). In this case, for example, according to the electron micrograph (Figs. 2-1 to 2-4) of the powder obtained in Example 11, it is presumed that the reason is that the obtained powder is in the form of a thin plate and has no surface. Tiny rough smooth particles. On the other hand, Comparative Examples 1, 6 to 9, 12, 13, 15, and 17 are examples of the manufacturing method of the present invention without the step (II), and the comparative examples 2 to 5, 14, and 16 are the steps (II). Where the temperature or humidity is out of the range, Comparative Examples 9 to 12 are for the high crystalline state (i.e., the half-height width of the peak derived from the (003) plane is less than 0.4) before the step (II). For example, the powders obtained in Examples 1 to 21 were excellent in the touch feeling on the skin when they were contained in the powders obtained in Comparative Examples 1 to 17 (see Tables 3 and 4).

Further, according to Figs. 3-1 to 3-3 and Fig. 4, it is understood that the plate-like hydrotalcite-type particles obtained by the production method of the present invention are excellent in adsorption ability of ammonia gas and phosphorus compound. For example, in the case of using the powder obtained in Example 11, since the ammonia concentration did not change after 1 hour and 22 hours (see Fig. 4), it was found that the adsorption equilibrium was reached in 1 hour. On the other hand, the powder obtained in Comparative Example 12 was a Zn-Al type granular hydrotalcite, and the specific surface area (SSA) thereof was substantially the same as that of the powder obtained in Example 11, but was obtained by using Comparative Example 12. In the case of using the powder obtained in Example 11, the ammonia gas adsorption ability was remarkably higher (see Fig. 4). Therefore, it is understood that the plate-like hydrotalcite-type particles (Zn-Al type) synthesized in a wet environment have a particularly high ammonia gas adsorption ability. Further, regarding the powder obtained in Example 11, before and after the adsorption of ammonia gas The color change of the powder was not observed by visual observation. Further, the powder obtained by adsorbing the ammonia gas in the powder obtained in Example 11 for 22 hours was filtered, washed with water, dried, and subjected to the same ammonia gas adsorption test again, and the same adsorption characteristics as in the initial stage were obtained. It can be seen that it can be reused after adsorption.

Therefore, it is understood that the production method of the present invention can easily and easily impart plate-shaped hydrotalcite-type particles which are particularly excellent in slidability and which are excellent in the adsorption ability of ammonia gas and phosphorus compound.

Claims (5)

A method for producing plate-shaped hydrotalcite-type particles, which is a method for producing plate-shaped hydrotalcite-type particles, characterized in that the manufacturing method comprises the following steps (I) and (II): step (I): use selection At least one of a group consisting of a free zinc compound and a compound containing a Group 2 element of the periodic table and an aluminum compound as a raw material to obtain a precursor; and step (II): at a temperature of 75 to 150 ° C and a relative humidity of 75 to 100% The precursor is maintained in an environment of RH; the precursor is derived from the half-height of the peak of the (003) plane and is 0.4 or more. The method for producing a plate-like hydrotalcite-type particle according to the first aspect of the invention, wherein the precursor is supplied in a powder form before the step (II). The method for producing a plate-like hydrotalcite-type particle according to claim 1 or 2, wherein the zinc compound is at least one selected from the group consisting of zinc hydroxide, zinc oxide, basic zinc carbonate, and zinc sulfate. . The method for producing a plate-like hydrotalcite-type particle according to any one of claims 1 to 3, wherein the aluminum compound is at least one selected from the group consisting of aluminum hydroxide, aluminum oxide, and aluminum sulfate. The method for producing a plate-like hydrotalcite-type particle according to any one of claims 1 to 4, wherein the production method produces a plate-like hydrotalcite-type particle represented by the following formula (1), (R) _{1 -x} (Al) _x (OH) ₂ (A ^n- ) _{x / n} ‧ mH ₂ O (1) (wherein R represents at least one selected from the group consisting of a zinc element and a group 2 element of the periodic table The element; A ^n- represents an interlayer anion of n valence; x and n are each a condition satisfying the conditions of 0.2 ≦ x ≦ 0.4, 1 ≦ n ≦ 4; m is a number of 0 or more).