JPH07278841A - Colored inorganic small body and color coating method of inorganic small body - Google Patents

Abstract

PURPOSE:To provide a method to easily color-coat an inorg. small body. CONSTITUTION:An acetylacetonate chelate complex of a specified metal, reducing agent, and inorg. small body are added to an org. solvent and heated under stirring and specified conditions. The specified conditions are determined so that all of the complex is not completely reduced to metal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored inorganic fine particle which is effectively used as a paint, an ink material and the like, and a method for coloring the inorganic fine particle.

[0002]

2. Description of the Related Art For example, it is known to use metal-coated inorganic fine particles as a paint. And, as its manufacturing method, generally, an electroless plating method,
The metallizing method is adopted. However, in the electroless plating method, the work is complicated because pretreatment is required. Further, in the metallizing method, the size of the device is large. Therefore, mass production was impossible by either method.

[0003]

DISCLOSURE OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION As a method for solving the above-mentioned drawbacks of the conventional manufacturing method, we have proposed the following method (Japanese Patent Application Nos. 4-196299 and 5-31).
4207). In this method, an acetylacetonato chelate complex of a predetermined metal, a reducing agent, and inorganic fine particles are added to an organic solvent, and the mixture is heated under reflux with stirring. According to this method, the metal-coated inorganic fine particles can be obtained very easily. However, the color of the coated inorganic fine particles is limited to the color of the metal obtained by reducing the acetylacetonato chelate complex of the above-mentioned predetermined metal, that is, black. Therefore, in consideration of the demands of consumers, we studied to obtain a chromatic coating layer, that is, a colored inorganic fine body.

[0004]

OBJECTS OF THE INVENTION It is an object of the present invention to provide a colored inorganic microparticle, and to provide a method by which the inorganic microparticle can be color-coated very easily.

[0005]

In the colored inorganic fine particles of the present invention, the inorganic fine particles are an acetylacetonato chelate complex of a predetermined metal, a simple substance of the metal, a hydrate of the metal, and the complex. Is coated with a mixture consisting of an intermediate product produced before reduction.

In addition, the method for coloring and coating the inorganic fine particles of the present invention comprises adding an acetylacetonato chelate complex of a predetermined metal, a reducing agent, and the inorganic fine particles to an organic solvent under predetermined conditions and heating while stirring. How to do
The above-mentioned predetermined condition is characterized in that all of the above complexes are not completely reduced to metal.

The above-mentioned predetermined conditions are as follows (1), (2)
Can be adopted. (1) The amount of the reducing agent was made smaller than the reaction equivalent to the above complex, (2) the heating temperature was made lower than the reflux temperature.

The following are listed as the inorganic fine particles. (1) Inorganic fine powder, 0.01-100 μm
(2) Inorganic fibers or whiskers with a diameter of 0.1 to 100 μm and a length of 1 to 1000 μm, which are ceramics, cermets, metallic diamonds, or clay minerals of (3) Inorganic flakes, which are diamond or clay minerals, having a diameter of 0.1 to 100 μm and a thickness of 0.1.
It is a ceramic, cermet, metallic diamond, or clay mineral of 100 μm. The ceramics are titanium oxide, chromium oxide, aluminum oxide, silicon oxide, etc., and the cermet is silicon carbide, silicon nitride, titanium nitride, aluminum nitride, tungsten carbide, chromium carbide, etc., and clay minerals. Is
Examples include mica and iron oxide.

The predetermined metal includes nickel, iron, cobalt, copper, zinc, chromium, molybdenum, titanium, vanadium, manganese, tungsten, silver, platinum, gold, palladium, beryllium, magnesium, aluminum, indium, gallium, germanium. , Uranium, cadmium, calcium, strontium, barium, scandium, cerium, neodymium, samarium and the like.

As the reducing agent, hydrides or hydrazines are preferably used. The hydrides include sodium borohydride, lithium hydride, potassium hydride, lithium aluminum hydride, potassium borohydride, and the like, and the hydrazines include hydrazinium sulfate, hydrazine, hydrazinium monochloride, and hydrazinium dichloride. Etc.

[0011]

When an acetylacetonato chelate complex of a given metal is reduced in an organic solvent, ultrafine particles of the metal are obtained. However, in the present invention, the above complex is not completely reduced to the metal. Therefore, in addition to the ultrafine particles of the metal, the unreacted complex, the hydrate of the metal, and the intermediate product generated until the complex is reduced are generated. These are bound to the surface of the inorganic microparticles during the production stage, and the surface of the microparticles is covered with a mixture of these. The mixture is a charged metal, hydrate,
Since it contains an intermediate product, it develops a color caused by them.

The above-mentioned mixture covering the surface of the fine particles has a very good lipophilicity because it also contains an organic compound which is one of intermediate products. Therefore, the inorganic fine particles covered with the above mixture have very excellent dispersibility in the coating material.

[0013]

EXAMPLES Examples of the present invention will be described below. The present invention is not limited to these examples. (Example 1) Tris (acetylacetonato) aluminum (hereinafter referred to as "aluminum complex") 1.0 × 10 ^-2 mol was dissolved in 150 ml of diphenyl ether, and 0.4 mol of sodium borohydride was added thereto, In this bath, calcium carbonate whiskers having a diameter of 2 μm, a length of 5 to 15 μm, and an amount of 5.0 m ^{2 in} terms of surface area were placed, and heated and refluxed at 240 ° C. for 3 hours while stirring. The whiskers obtained were filtered, washed and dried.
The obtained whiskers were colored yellow.

FIG. 1 is an SEM photograph showing the obtained whiskers, and FIG. 2 is an X-ray diffraction diagram of the obtained whiskers. Further, FIG. 3 is an X-ray diffraction diagram of uncoated calcium carbonate whiskers shown for comparison. As can be seen in FIG. 1, the surface of the whiskers is covered with precipitates of irregular size and protrusions. As can be seen by comparing FIG. 2 with FIG. 3, the whiskers obtained in this example have substantially the same pattern as that of the uncoated whiskers. Therefore, the deposits shown in FIG. The complex and aluminum that should be obtained by reducing the aluminum complex are scarcely contained. In FIG. 2, broad peaks are observed near 2θ of 5 to 10 and 30 to 40. This peak suggests the presence of amorphous compounds such as organic compounds and metal hydrates. Therefore, the precipitate shown in FIG.
It is considered to be a mixture consisting of a small amount of an aluminum complex and aluminum, an aluminum hydrate, and an intermediate product (the above-mentioned organic compound or the like) produced until the aluminum complex is reduced.

As described above, in this example, since the aluminum complex was not completely reduced to aluminum, the precipitate was composed of the mixture,
Therefore, the whiskers covered with the above-mentioned precipitates are yellow. That is, in this example, the whisker coating treatment was performed while suppressing the reduction reaction of the aluminum complex, so that whiskers colored in yellow were obtained.

(Examples 2 to 5) In Example 1, various kinds of complexes shown in Table 1 were used in place of the aluminum complex, and other processes were performed in the same manner. Also, in Table 1,
The tinted color of the whiskers is also shown.

[0017]

[Table 1]

4 to 7 are SEM photographs showing the whiskers obtained in Examples 2 to 5, respectively. Similar to FIG. 1, the surface of the whiskers is covered with precipitates having irregular sizes and protrusions. This precipitate is also a mixture of a small amount of the complex and a simple substance of the metal contained in the complex, a hydrate of the metal, and an intermediate product produced until the complex is reduced, as in the case of Example 1. Is considered to be.

As described above, also in Examples 2 to 5, whisker coating treatment was carried out while suppressing the reduction reaction of the complex, and whiskers colored in various chromatic colors were obtained.

(Comparative Examples 1 to 4) In Example 1, the following various complexes were used instead of the aluminum complex, and the other processes were performed in the same manner. Comparative Example 1 ... Tris (acetylacetonato) cobalt (I
II) -Comparative Example 2 ... Bis (acetylacetonato) copper (II) -Comparative Example 3 ... Bis (acetylacetonato) cobalt (II)
・ Dihydrate ・ Comparative Example 4 ... Tris (acetylacetonato) iron (III)

In each of Comparative Examples 1 to 4, the obtained whiskers were colored black. FIG. 8 is an SEM photograph showing the whiskers obtained in Comparative Example 1, and FIG. 9 is an X-ray diffraction diagram of the whiskers. As can be seen from FIG. 8, the surface of the whiskers is covered with precipitates of irregular size and protrusions. On the other hand, in FIG. 9, a cobalt peak, that is, a metal peak is recognized. Therefore, the precipitate shown in FIG. 8 is considered to be a metal.

FIG. 10 is an SEM photograph showing the whiskers obtained in Comparative Example 2, and FIG. 11 is an X-ray diffraction diagram of the whiskers. As can be seen from FIG. 10, the whisker surface is
Covered with precipitates of uneven size and protrusions. On the other hand, in FIG. 11, a copper peak, that is, a metal peak is recognized. Therefore, the precipitate shown in FIG. 10 is considered to be a metal.

FIG. 12 is an SEM photograph showing the whiskers obtained in Comparative Example 3, and FIG. 13 is an SEM photograph showing the whiskers obtained in Comparative Example 4. As can be seen from both figures, the surface of the whiskers is covered with precipitates of irregular sizes and protrusions. This precipitate is considered to be a metal.

Comparative Examples 1 to 4 show the following. That is, even under the same conditions as in Example 1, the complexes used in Comparative Examples 1 to 4 are conditions in which all of the complexes are completely reduced. Therefore, the conditions for reducing the complex need to be set appropriately according to the type of the complex.

Example 6 A predetermined amount of tris (acetylacetonato) cobalt (III) (hereinafter referred to as cobalt complex) or bis (acetylacetonato) copper (II) (hereinafter referred to as copper complex) was added to 150 ml of anisole. Called))
A predetermined amount of hydrazine monohydrate was added to this, and aluminum flake having a diameter of 17.2 μm, a length of 2 μm and a surface area equivalent of 5.0 m ² was added to the bath,
The mixture was heated under reflux at 115 ° C. for 30 minutes while stirring. The flakes obtained were filtered, washed and dried. The amounts of the cobalt complex or the copper complex and hydrazine monohydrate were the combinations shown in Table 2. In addition, Table 2 shows the colored color of the obtained flakes corresponding to each combination.

[0026]

[Table 2]

When X-ray diffraction was performed on the black colored flakes, a peak indicating cobalt or copper, that is, a metal peak was observed in each case. However, for flakes colored other than black,
Many broad peaks due to the amorphous compound were observed, and almost no metal peaks were observed.

FIG. 14 is an SEM photograph showing bluish purple flakes in the case of the cobalt complex of 15 mmol and hydrazine monohydrate of 150 mmol. 14
In, it is observed that crystals of the organic compound of cobalt are deposited on the flakes. This precipitate is considered to be the causative agent of blue-violet.

As can be seen from Table 2, for example, when the amount of hydrazine monohydrate was changed with respect to 5 mmol of the cobalt complex, chromatic color was obtained at 30 mmol and 150 mmol, but black at 300 mmol. became. 30 mmol and 150 mmol are theoretically larger than the reaction equivalent to the cobalt complex, but experimentally they are smaller than the reaction equivalent in consideration of reaction loss and efficiency. On the contrary, it becomes large at 300 mmol. Therefore,
Making the amount of hydrazine monohydrate smaller than the reaction equivalent to the cobalt complex, that is, making the amount of the reducing agent smaller than the reaction equivalent to the complex, satisfies the condition that all of the complex is not completely reduced to the metal. It will be.

(Examples 7 to 13) 150 ml of anisole
The following various kinds of complexes (1.0 × 10 ⁻² mol) were dissolved, and anhydrous hydrazine (0.3 mol) was added thereto, and in this bath, the diameter was 2 μm, the length was 5 to 15 μm, and the surface area conversion was 5. Add silicon carbide whiskers in an amount of 0 m ² ,
The mixture was heated under reflux at 115 ° C. for 30 minutes while stirring. The whiskers obtained were filtered, washed and dried. Tables 3 and 4 show the colored colors of the various complexes and the resulting whiskers, and Table 3 shows for Examples 7-13.

[0031]

[Table 3]

As for the above reaction conditions, in Examples 7 to 13, all of the complexes were not completely reduced to metals. Therefore, in Examples 7 to 13, the whiskers are colored chromatically.

[0033]

[Other Example] In Example 6, it is adopted that the amount of the reducing agent is less than the reaction equivalent to the complex as a condition that all of the complex is not completely reduced to a metal. A heating temperature lower than the reflux temperature may be adopted. If the heating temperature is lower than the reflux temperature, the reactivity of the reducing agent with respect to the complex is naturally suppressed.

In the above embodiment, the inorganic whiskers and the inorganic flakes are used, but instead of these, 0.0
Inorganic fine powder with a size of 1-100 μm, diameter 0.1
An inorganic fiber having a length of -100 μm and a length of 1-1000 μm may be used. The inorganic whiskers have a diameter of 0.
The present invention is not limited to the above examples as long as it is 1 to 100 μm and the length is 1 to 1000 μm. The inorganic flakes are not limited to the above examples as long as they have a diameter of 0.1 to 100 μm and a thickness of 0.1 to 100 μm. Further, as the kind of the inorganic fine powder, the inorganic fiber, the inorganic whisker, or the inorganic flake, ceramics, cermet, metal diamond, clay mineral, etc. other than those used in the above examples may be used.

The metal coated in the present invention is
Not limited to the above embodiment, nickel, iron, molybdenum, titanium, vanadium, tungsten, silver, platinum,
Gold, palladium, beryllium, magnesium, indium, gallium, germanium, uranium, cadmium, calcium, strontium, barium, scandium,
It can be arbitrarily selected from cerium, neodymium, or samarium and used. Of course, for each metal, conditions are appropriately set such that all of the acetylacetonato chelate complex of each metal is not completely reduced to the metal.

Further, the reducing agent used in the present invention is not limited to those in the above-mentioned examples as long as it is a hydride or hydrazine.

[0037]

As described above, the colored inorganic fine particles of the present invention have the following effects. (1) According to the colored inorganic fine particles according to claim 1, since the mixture coating the inorganic fine particles contains a charged metal, a metal hydrate, and an intermediate product, they are caused by them. The chromatic color that was created is expressed. Therefore, it is possible to sufficiently meet the demands of consumers regarding color.

Further, since the above mixture contains an organic compound which is one of the intermediate products, the colored inorganic fine particles have a good lipophilicity, and therefore, they should be used by being dispersed well as a pigment in a paint. You can

(2) The colored inorganic fine particles according to claims 2 to 4 have various shapes such as fine powder, fibers, whiskers, and flakes, and thus can be used for various purposes.

(3) According to the colored inorganic fine particles of the fifth aspect, various chromatic colors are exhibited by hydrates and intermediate products related to various metals.

According to the method for coloring and coating the inorganic fine particles of the present invention, the following effects can be obtained.

(4) According to the method of claim 6, the inorganic fine particles can be colored and coated.

Moreover, since it is sufficient to add the metal acetylacetonato chelate complex, the reducing agent, and the inorganic fine particles to the organic solvent under predetermined conditions and heat with stirring, it can be carried out extremely easily.

(5) According to the methods described in claims 7 and 8, it is possible to easily set conditions under which all the complexes are not completely reduced to the metal.

(6) According to the methods described in claims 9 to 11, it is possible to color-coat the inorganic fine powder, the inorganic fibers, the inorganic whiskers, or the inorganic flakes.

(7) According to the method of claim 12, it is possible to color-coat the inorganic fine particles in various chromatic colors corresponding to each metal.

(8) According to the method of the thirteenth aspect, it is possible to satisfactorily color and coat the inorganic fine particles.

[Brief description of drawings]

FIG. 1 is a photograph replacing a drawing showing a particle structure,
3 is an SEM photograph showing the whiskers obtained in Example 1.

2 is an X-ray diffraction diagram of whiskers obtained in Example 1. FIG.

FIG. 3 is an X-ray diffraction diagram of uncoated calcium carbonate whiskers for comparison with FIG. 2.

FIG. 4 is a photograph replacing a drawing showing a particle structure,
5 is an SEM photograph showing whiskers obtained in Example 2.

FIG. 5 is a photograph replacing a drawing showing a particle structure,
5 is an SEM photograph showing whiskers obtained in Example 3.

FIG. 6 is a photograph replacing a drawing showing a particle structure,
5 is an SEM photograph showing whiskers obtained in Example 4.

FIG. 7 is a photograph replacing a drawing showing a particle structure,
9 is an SEM photograph showing whiskers obtained in Example 5.

FIG. 8 is a photograph replacing a drawing showing a particle structure,
5 is an SEM photograph showing whiskers obtained in Comparative Example 1.

9 is an X-ray diffraction diagram of whiskers obtained in Comparative Example 1. FIG.

10 is a photograph replacing a drawing showing a particle structure, and an SEM showing the whiskers obtained in Comparative Example 2. FIG.
It is a photograph.

FIG. 11: X of whiskers obtained in Comparative Example 2
It is a line diffraction diagram.

FIG. 12 is a photograph instead of a drawing showing a particle structure, and an SEM showing the whiskers obtained in Comparative Example 3.
It is a photograph.

FIG. 13 is a photograph instead of a drawing showing a particle structure, and an SEM showing the whiskers obtained in Comparative Example 4.
It is a photograph.

FIG. 14 is a SEM image showing the flakes obtained in one example of Example 6, which is a photograph instead of a drawing showing a particle structure.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C09C 3/06 PBS // C23C 18/31 A

Claims (13)

[Claims] 1. An inorganic microparticle comprises an acetylacetonato chelate complex of a predetermined metal, a simple substance of the metal, a hydrate of the metal, and an intermediate product produced by the reduction of the complex. A colored inorganic microparticle characterized by being coated with a mixture. 2. The inorganic fine body is an inorganic fine powder,
The colored inorganic fine particles according to claim 1, which are ceramics, cermets, metallic diamonds, or clay minerals having a size of 0.01 to 100 µm. 3. The inorganic fine particles are inorganic fibers or inorganic whiskers, and are ceramics, cermets, metallic diamonds, or clay minerals having a diameter of 0.1 to 100 μm and a length of 1 to 1000 μm. Colored inorganic fine particles. 4. The inorganic fine particles are inorganic flakes having a diameter of 0.1 to 100 μm and a thickness of 0.1 to 100.
The colored inorganic fine particles according to claim 1, which are ceramics, cermet, metallic diamond, or clay mineral having a size of μm. 5. The predetermined metal is nickel, iron, cobalt, copper, zinc, chromium, molybdenum, titanium, vanadium, manganese, tungsten, silver, platinum, gold, palladium, beryllium, magnesium, aluminum, indium, gallium, Germanium, uranium, cadmium,
The colored inorganic fine particle according to claim 1, which is calcium, strontium, barium, scandium, cerium, neodymium, or samarium. 6. A method of adding an acetylacetonato chelate complex of a predetermined metal, a reducing agent, and an inorganic fine particle to an organic solvent under predetermined conditions and heating the mixture with stirring, wherein the predetermined conditions are: A method for coloring and coating inorganic fine particles, characterized in that all of the above complexes are not completely reduced to metal. 7. The method for coloring and coating inorganic fine particles according to claim 6, wherein the amount of the reducing agent is set to be less than the reaction equivalent to the complex as the predetermined condition. 8. The method for coloring and coating inorganic fine particles according to claim 6, wherein the heating temperature is lower than the reflux temperature as a predetermined condition. 9. The inorganic fine body is an inorganic fine powder,
The method for coloring and coating inorganic fine particles according to claim 6, which is ceramics, cermet, metal diamond, or clay mineral having a size of 0.01 to 100 µm. 10. The inorganic fine particles are inorganic fibers or inorganic whiskers, and are ceramics, cermets, metallic diamonds, or clay minerals having a diameter of 0.1 to 100 μm and a length of 1 to 1000 μm. Method for coloring and coating inorganic fine particles of the above. 11. The inorganic fine particles are inorganic flakes, having a diameter of 0.1 to 100 μm and a thickness of 0.1 to 100.
The method for coloring and coating inorganic fine particles according to claim 6, which is ceramics, cermet, metallic diamond, or clay mineral having a thickness of μm. 12. The predetermined metal is nickel, iron, cobalt, copper, zinc, chromium, molybdenum, titanium, vanadium, manganese, tungsten, silver, platinum, gold, palladium, beryllium, magnesium, aluminum, indium, gallium, Germanium, uranium, cadmium,
The method for coloring and coating inorganic fine particles according to claim 6, which is calcium, strontium, barium, scandium, cerium, neodymium, or samarium. 13. The method for coloring and coating inorganic fine particles according to claim 6, wherein the reducing agent is a hydride or a hydrazine.