JP2968118B2 - Scale-like composite pigment having durability gloss and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flaky composite pigment having a durable gloss and a method for producing the same. More specifically, the present invention relates to a flaky composite pigment having a durable gloss, having a composite coating layer composed of a zirconium compound / chromium-containing composite material, having excellent water resistance and weather resistance, and a method for producing the same. Things.

[0002]

2. Description of the Related Art Among the quality requirements for exterior coating films for automobiles and the like, it is particularly important that the appearance quality does not deteriorate even when exposed to various outdoor weather conditions for a long period of time.
It has been known that a chalking phenomenon called chalking occurs in a coating film in which titanium dioxide is dispersed and contained in a resin as a pigment. As means for suppressing such properties possessed by titanium dioxide, at least one selected from chromium compounds, silicon compounds, phosphorus compounds, zirconium compounds, etc. is doped into titanium dioxide for pigments or the surface thereof is Methods of coating and stabilizing have been proposed.

[0003] Paints in which aluminum flake pigments are dispersed and contained in a resin are used for exterior coating for automobiles, and coatings containing such pigments are also applied when exposed to various weather conditions. It is known that the film appearance deteriorates. An outdoor exposure test is known as a method for evaluating the durability against such weather conditions, but other accelerated evaluation methods such as an accelerated weather resistance test, a wet test, and a high-temperature water immersion test are also known. This makes it possible to evaluate the deterioration of the gloss and color tone of the coating film surface.

Conventionally, metal oxides such as titanium oxide and iron oxide, or titanium oxide and iron oxide have been applied to the surface of flaky pigment powders such as mica flakes and mica-like iron oxide (hereinafter referred to as mica flakes and the like). It is known to apply a coating to prepare a pigment having pearl luster and to use such a luster pigment as a colorant for paints, inks, plastics and the like. However, when a paint using a glossy pigment obtained by coating the surface of such a mica flake with a metal oxide such as titanium dioxide is applied to the exterior coating of an automobile or the like, the coating film is made of aluminum flake pigment. In a water resistance test such as a high-temperature water immersion test, gloss deterioration of the coating film occurs, which is completely unsuitable for practical use, similarly to a coating film composed of a paint dispersed and contained in a resin.

[0005] As a cause of deterioration of the gloss and color tone of the coating film surface, water molecules penetrate the coating film and reach the pigment surface to form fine blisters. It is considered that fine pores are formed therein, and the pores remarkably scatter light, thereby deteriorating the gloss and color tone of the coating film surface. As a method for preventing the deterioration of the appearance of a coating film containing a mica flake or the like coated with such a metal oxide as a pigment, a surface treatment method applied to titanium dioxide for a pigment is usually applied. Can be easily analogized. However, pearlescent pigments composed of metal oxide-coated mica flakes and the like have properties much more complicated than mere titanium dioxide for pigments. Even if applied to pearlescent pigments composed of flakes of mica flakes, the effect of improving water resistance is not available or is insufficient.

On the other hand, as a method for imparting water resistance to titanium dioxide-coated mica flakes, JP-A-47-34527 discloses a pigment obtained by treating the surface of a pigment base with methacrylate chromium chloride and a method for producing the same. Have been. JP-A-54-96534 discloses that a chromium (III) hydroxide coating layer is formed by adding a basic substance such as sodium hydroxide to a chromium (III) compound aqueous solution and utilizing a neutralization precipitation reaction. A method for doing so is disclosed. Also,
JP-A-58-69258 and JP-A-58-6925
No. 9 discloses a method for producing a pearlescent pigment by forming a protective layer with chromium oxide and / or chromium phosphate and calcining the obtained pigment, and a pearlescent pigment obtained thereby. . These methods have some effects, but are not sufficient, to improve the water resistance of pearlescent pigments composed of titanium dioxide-coated mica flakes.

On the other hand, JP-A-58-174449 discloses that
A basic chromium or aluminum compound,
A method for producing a hydrophobic pearlescent pigment using a carboxylic acid containing more than 4 carbon atoms per carboxyl group in the molecule is disclosed. Also, JP-A-59-7
No. 8265 discloses a pearlescent pigment having methacrylate chromium chloride deposited thereon. These methods use special raw materials such as methacrylate and chromium compounds, which are not only economically disadvantageous, but also
It is difficult to say that the obtained durability improving effect is sufficient. Further, Japanese Patent Application Laid-Open Nos.
No. 2067 discloses a method for producing a pearlescent pigment by hydrolyzing a zirconium compound in the presence of hypophosphite and attaching hydrous zirconium oxide to the surface of a pigment substrate. However, these methods require a very complicated process and strict process control, so that a disadvantage in manufacturing cannot be denied.

Generally, since the surface of a metal material is covered with an oxide, if the metal material is directly coated without being subjected to a surface treatment, a blistered film called blister is generated due to the influence of moisture, temperature and the like. It is known to have the problem that Amorphous alloys are disclosed in, for example,
In the case of a coating film formed from a paint obtained by dispersing and containing flake-form powder in a resin according to the method described in Japanese Patent No. 87209, similar swelling occurs at the interface between the pigment and the resin. As a result, the appearance of the coating film is significantly impaired, and this is a serious obstacle in practical use.

A pearlescent pigment obtained by using flaky powder such as mica flakes as a pigment base material and coating it with a metal oxide is coated with titanium dioxide. A colored mica titanium pigment or flaky flake obtained as a lower titanium oxide by the method described in JP-A-3-79673 or the like is used as a pigment substrate, and electroless plating or vapor deposition plating from an aqueous solution ( (Including sputtering, PVD, CVD, etc.) or the like to form a metal coating, or, for example, JP-A-1-108267 and JP-A-1-1044673.
Pigment obtained by adhering a metal or alloy to a part of the surface of a pigment substrate made of flaky powder,
When dispersed in the resin, the same phenomenon as described above occurs at the interface between the resin and the pigment, and there is a problem that the coating film and the long-term appearance quality are deteriorated. It is hindering.

[0010]

DISCLOSURE OF THE INVENTION The present invention has sufficient durability even under long-term exposure to various harsh natural environments such as exterior coating of automobile bodies, that is, long-term durability in color tone and gloss. An object of the present invention is to provide a flaky composite pigment having gloss and a method for producing the same.

[0011]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a composite coating layer made of a zirconium-chromium-containing composite material is formed on the surface of the flaky inorganic pigment particles. It has been found that by forming such a pigment, a flaky composite pigment having a durable gloss having excellent moisture resistance, gloss retention and dispersibility can be obtained, and the present invention has been completed.

The scaly composite pigment having a durable luster according to the present invention covers the surface of a substrate (A) composed of scaly inorganic pigment particles and the surface of a substrate (A) composed of the scaly inorganic pigment particles. And a composite coating layer (B) comprising a zirconium / chromium-containing composite material, wherein the substrate (A) comprising the flaky inorganic pigment particles comprises: (1) a core body comprising the inorganic flaky particles; Powder coated with a surface layer made of at least one selected from metals, alloys and metal oxides; and (2) at least one metal or alloy coating on the surface of a core made of inorganic flaky powder. And a powder coated with a surface layer formed by laminating at least one metal oxide film layer in an arbitrary order; and (3) (i) a core body composed of inorganic flaky powder, And (ii)
The surface of the core made of inorganic flaky powder is at least one type selected from a composite core coated with a metal oxide film layer, and at least one type selected from metals and alloys. A powder in which a plurality of coating layers are formed in an island-like manner; and in each of the powders (1), (2) and (3), the inorganic flaky powder The core body composed of particles comprises at least one selected from the group consisting of (a) mica flakes, (b) aluminum flakes, (c) amorphous alloy flakes, and (d) mica-like iron oxide (MIO) powder. A flaky composite pigment having a durable gloss.

Further, the method for producing a scale-like composite pigment having a durable luster according to the present invention is characterized in that the base (A) comprising the inorganic scale-like inorganic pigment powder is prepared by mixing at least one zirconium ion supplying compound with at least one zirconium ion supplying compound. Suspended in an acidic treatment aqueous solution containing one kind of chromium trivalent ion supplying compound and having a pH value of 1.0 to 5.0.
A composite coating layer made of a zirconium-chromium-containing composite material is formed on the surface of the pigment particles by heat treatment at a temperature of ~ 90 ° C, and the flaky pigment powder obtained by the heat treatment is collected. And then washed with water and dried.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the scaly composite pigment of the present invention, the weight ratio (A) / (B) of the pigment base (A) to the composite coating layer (B) is 1000 / 0.2 to 1000. / 2
0, preferably 1000/1 to 1000/1
More preferably, it is 0. In addition, composite coating layer (B)
Preferably covers the entire surface of the pigment substrate, but may cover a part of this surface,
In this case, it is preferable that 10% or more of the surface area of the pigment substrate (A) is covered.

In the present invention, the scaly inorganic pigment particles used as the base (A) of the scaly composite pigment include the following powder materials: (1) The surface of a core composed of inorganic scaly particles is formed of a metal, an alloy or a metal. Powder coated with at least one surface layer selected from oxides, (2) at least one metal or alloy film layer, and at least one layer of a core body made of inorganic flaky powder. Powder coated with a surface layer formed by laminating the metal oxide film layers in any order; (3) (i) a core composed of inorganic flaky powder;
i) at least one surface selected from a composite core in which the surface of a core composed of inorganic flaky particles is coated with a metal oxide coating layer, and at least one surface selected from a metal and an alloy; Powder in which a plurality of coating layers are formed in an island shape. In each of the powders (1), (2) and (3), the core made of the inorganic flaky powder is (a) mica flake, (b) aluminum flake, (c) amorphous alloy flake And (d) mica-like iron oxide (MIO) powder. Each of these powder materials (1), (2), and (3) has a flaky shape, a thickness of 0.2 to 5 μm, and a diameter (major axis and minor axis) of 5 μm. It is preferably about 500 μm.

The amorphous alloy flake (c) used in the present invention is, for example, 10% Ni, 10% Cr, 2% M
o, 12% P, 8% C, amorphous alloy of residual Fe, or 5%
It is preferable to be selected from flakes composed of an amorphous alloy of Ni, 15% Cr, 2% Mo, 11% P, 10% C, and the remaining Fe.

In the powder materials (1), (2) and (5) used as the substrate in the present invention, the inorganic flaky powder used as the core is composed of the core material (a), (B), (c), and (d).

Further, in the powder materials (1) to (3), the metal or alloy used for forming the surface layer, the coating layer or the island coating layer is, for example, silver, gold, copper, palladium, or the like.
It can be selected from cobalt, aluminum, nickel-phosphorus alloy, nickel-boron alloy, nickel-cobalt-phosphorus alloy, nickel-tungsten-phosphorus alloy, silver-gold alloy, cobalt-phosphorus alloy and the like.

Further, in the powder materials (1), (2) and (3), the metal oxide used for forming the surface layer or the coating layer is, for example, titanium dioxide, iron oxide, aluminum hydroxide, It can be selected from silicon dioxide, zirconium dioxide, tin dioxide and the like.

In the powder materials (1) to (3), the weight ratio of the core or the composite core to the surface layer or the island-like coating layer is preferably 99/1 to 30/70. In the powder material (2), a titanium dioxide film layer is preferably formed as a metal oxide film layer on the core, and a silver film layer is formed as a metal film layer on the outermost surface of the surface layer. It is preferably formed, and the weight ratio of the metal or alloy coating layer to the metal oxide coating layer is 5/95 to 5
It is preferably 0/50.

In the above powder material (3), the weight ratio of the core made of inorganic flaky powder in the composite core (ii) to the metal oxide film layer is 95/5 to 40/60. It is preferable that the island-shaped coating layer covers 0.05 to 95% of the surface of the core (i) or the composite core (ii). 01-5 μm
It is preferable that the particles have an average particle size of and are distributed in islands apart from each other.

In the present invention, the composite coating layer (B) made of a zirconium / chromium-containing composite material comprises a scaly inorganic material powder forming a substrate, at least one kind of zirconium ion supplying compound and at least one kind of chromium. The suspension was suspended in an aqueous acid treatment solution containing a trivalent ion-supplying compound and adjusted to a pH of 1.0 to 5.0.
It is obtained by heat treatment at 0 to 90 ° C. The heat treatment temperature is from 20C to 90C.

Although there is no particular limitation on the zirconium ion supplying compound, it is generally preferable to select from the compounds selected from fluorinated zirconic acid, ammonium fluorinated zirconate, and alkali metal fluorinated zirconate.

The chromium trivalent ion supplying compound is not particularly limited, but trivalent chromium phosphate, trivalent fluoric acid salt, trivalent chromium nitrate, trivalent chromium sulfate, trivalent chromium sulfate, and the like.
It is preferably selected from chromium (IV) salts, trivalent chromium carbonate salts and trivalent chromium chromate salts.

The trivalent chromium chromate can be produced, for example, by partially reducing an aqueous solution of chromic anhydride using a suitable reducing agent. As the reducing agent used at this time, generally known reducing agents can be used, but preferably, monohydric alcohols such as methanol, ethanol and propanol, polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin, and glycolic acid , Tartaric acid, citric acid, lactic acid, oxycarboxylic acids such as ascorbic acid, aldehydes such as formaldehyde, phenol, pyrogallol, aromatic acids such as gallic acid, and tannins that decompose to form the reducing compound, It is possible to use one or more selected from glucose, saccharose, and polysaccharides such as dextrin and starch that are decomposed to produce them.

Further, the pH value of the acidic treatment aqueous solution is adjusted to 1.0 to 1.0.
In order to adjust to 5.0, at least one selected from inorganic acids and organic acids is used. Such inorganic acids and organic acids are not particularly limited, but are preferably inorganic acids such as phosphoric acid, sulfuric acid, nitric acid, hydrofluoric acid, and hydrochloric acid, carboxylic acids such as formic acid, acetic acid, oxalic acid, and benzoic acid, and tartaric acid. ,
Oxycarboxylic acids such as citric acid and lactic acid, and phenols such as carboxylate and tannic acid can be used. More preferably, one or more selected from phosphoric acid, sulfuric acid, nitric acid, hydrofluoric acid, and tannic acid can be used. .

In the method of the present invention, the weight ratio of zirconium ion to chromium trivalent ion (Zr
/ Cr) is preferably 1/20 to 10/1. If the Zr / Cr ratio is less than 1/20, the zirconium content in the obtained composite coating layer will be insufficient, and the necessary effect of improving durability cannot be obtained. If the Zr / Cr ratio exceeds 10/1, the above effects reach saturation, which is uneconomical.

In the method of the present invention, the pH of the aqueous acidic treatment solution
The value is adjusted between 1.0 and 5.0 as described above. this
When the pH value is less than 1.0, the film-forming reaction to the pigment is insufficient, and when the pH value is more than 5.0, an unnecessary precipitate is formed, which leads to waste of the drug, which is not economical.

The flaky inorganic pigment particles are suspended in the aqueous acidic solution adjusted in composition and pH as described above,
While stirring this, warm to a temperature of 20 to 90 ° C.
A composite film is formed on the surface of the pigment particles, the obtained composite pigment is collected, washed with water, and then dried at preferably 300 ° C. or less, so that it has excellent moisture resistance, gloss retention, and dispersibility. A flaky composite pigment having excellent durability gloss can be obtained. After suspending the scaly inorganic pigment particles for the substrate, the treatment temperature and treatment time with the required acidic treatment aqueous solution should be determined by industrial profitability, and accordingly the necessary treatment temperature and treatment time may be appropriately adjusted. Can be determined.

Although the composition of the coating layer of the zirconium-chromium composite material deposited on the surface of the pigment particles for the substrate by the above treatment according to the method of the present invention is not yet clear, according to XPS (X-ray photoelectron spectroscopic analysis), It is presumed that it is in a complex form of (IV) -chromium (III) oxide or hydroxide.

In the method of the present invention, there is no particular limitation on the drying temperature after filtration and collection of the composite pigment obtained by the above treatment and washing with water, but if it exceeds 300 ° C., the color tone of the obtained composite pigment may change. It is undesirable to bring.

The scaly composite pigment having a luster obtained in this way is suitable for being mixed with a thermosetting resin or a lacquer type resin or the like by a known method and used. Metal,
The coating layer applied to materials such as plastic, wood, concrete, glass, etc. shows satisfactory durability under outdoor conditions, especially water resistance enough to be used as a coloring agent for exterior paints for automobiles. And has excellent dispersibility, and can be used as a paint exhibiting excellent design properties without impairing the color tone and gloss of the pigment at all.

[0033]

The present invention will be described in detail with reference to the following examples, but the scope of the present invention is not limited by these examples.

Example 1 A particle size of 10 to 50 μm obtained by coating the surface of a mica flake with about 20% of titanium dioxide based on the weight of the mica flake.
90 g of m-metal oxide-coated mica flakes were suspended in 610 ml of water. Separately, it is an aqueous solution of chromium chromate, which is produced by a zirconium conversion of 0.62 g / liter of fluorinated zirconate and a tannic acid reduction method and contains about 20% of chromium trivalent ions with respect to total chromium. 90 ml of an aqueous solution containing an aqueous solution having a concentration of 10 g / liter was diluted to 290 ml with stirring, and phosphoric acid was added to adjust the pH to about 2.0 to prepare an acidic aqueous solution. This acidic treatment aqueous solution was added to the metal-coated mica flake suspension, and the mixture was heated to 60 ° C. with continued stirring, and this temperature was maintained for about 30 minutes. Next, the aqueous suspension was filtered,
The solid product was collected by filtration, washed with water, and dried at 120 ° C. for 3 hours.

Example 2 90 g of a metal oxide-coated mica flake having a particle size of 5 to 20 μm obtained by coating the surface of a mica flake with iron oxide at about 60% by weight of the mica flake was suspended in 400 ml of water. I let it. Separately, ammonium fluoride zirconate contains 2 g / l in terms of zirconium, and chromium trivalent ion contains 0.6 g / l in terms of chromium using chromium fluoride,
90 ml of an acidic aqueous solution adjusted to a pH of about 1.5 with phosphoric acid
Was diluted to 500 ml with stirring. This aqueous solution was added to the metal-coated mica flake suspension, and the mixture was heated to 90 ° C. while continuing to stir, and this temperature was maintained for about 10 minutes. Next, the aqueous suspension was filtered, and the solid product was collected by filtration, washed with water, and dried at 150 ° C. for 2 hours.

Example 3 Titanium dioxide having a particle size of 10 to 50 μm and obtained by coating the surface of mica flakes with about 40% by weight of the mica flakes of titanium dioxide and about 9% of low-order titanium oxide. 90 g of titanium-coated mica flakes were suspended in 610 ml of water.
Separately, 90 ml of an aqueous solution containing 1 g / l of ammonium fluoride zirconate in terms of zirconium and 10 g / l in terms of chromium using chromium trivalent ions using chromium sulfate is diluted to 290 ml with stirring, and this is diluted with phosphorus. An acidic aqueous solution adjusted to a pH of about 1.7 with an acid was prepared. This acidic aqueous solution was added to the above-mentioned metal-coated mica flake suspension, and the mixture was heated to 75 ° C. while stirring, and this temperature was maintained for about 20 minutes. Next, the aqueous suspension was filtered to collect a solid product, which was washed with water and dried at 110 ° C. for 4 hours.

Example 4 A mica flake was used as a core body, and aluminum was adhered to a part of its surface by a sputtering method.
90 g of metal-coated mica flakes having a particle size of 10 to 60 μm
Suspended in 10 ml. Separately, fluorinated zirconic acid is produced at 1.3 g / l in terms of zirconium, and is produced by a tannic acid reduction method.
90 ml of an aqueous solution containing 20 g / l of a chromium chromate aqueous solution containing about 20% of valence ions in terms of total chromium was prepared, diluted with stirring with 290 ml, and adjusted to pH 290 with phosphoric acid.
Was adjusted to about 1.8 to prepare an acidic aqueous solution. This acidic aqueous solution was added to the above-mentioned metal-coated mica flake suspension, and the mixture was heated to 60 ° C while stirring, and this temperature was maintained for about 30 minutes. Next, the aqueous suspension was filtered, and the solid product was collected by filtration, washed with water, and dried at 110 ° C. for 5 hours.

Example 5 The surface of mica flakes was coated with about 46% by weight of titanium dioxide, and a part of the surface was further coated with aluminum by sputtering to obtain a particle size of 5 to 20 μm. 90 g of mica flakes coated with two layers of metal oxide and metal were suspended in 610 ml of water. Separately, ammonium fluoride zirconate is converted to zirconium in an amount of 5 g /
Liter and chromium 3 obtained using chromium nitrate
90 ml of an aqueous solution containing 0.4 g / l of valent ions in terms of chromium was diluted to 290 ml with stirring to prepare an aqueous solution. This aqueous solution was added to the above metal-coated mica flake suspension, and tannic acid was further added to adjust the pH to about 3.0.
The acidic suspension was heated to 90 ° C. with stirring, and this temperature was maintained for about 10 minutes. Next, the aqueous suspension was filtered, and the solid product was collected by filtration, washed with water, and dried at 140 ° C. for 2 hours.

Example 6 Ni (10 atomic%), Cr (10 atomic%), Mo (2 atomic%), P (12 atomic%), C (8 atomic%), residual Fe and inevitable impurities And a powder having a thickness of 1 to 4 μm, an aspect ratio (ratio of major axis to thickness) of 10 to 100, and a ratio of minor axis to major axis of 1 to
5. 90 g of amorphous alloy flakes with minor and major dimensions of 10 to 400 μm were suspended in 610 ml of water.
Separately, fluorinated zirconate is converted to zirconium in an amount of 0.1.
An aqueous solution containing 62 g / liter and about 20% of chromium trivalent ion produced by the tannic acid reduction method and containing about 20% of the total chromium, and 90 ml of an aqueous solution containing 10 g / l in terms of total chromium was reduced to 290 ml with stirring. An acidic aqueous solution was prepared by diluting and adjusting the pH to about 2.0 with phosphoric acid. This acidic aqueous solution is added to the above-mentioned amorphous alloy powder suspension, and the mixture is heated to 60 ° C. while stirring is continued.
Hold for 0 minutes. Next, the aqueous suspension was filtered, and the solid product was collected by filtration, washed with water, and dried at 120 ° C. for 3 hours.

Example 7 The surface of a mica flake was coated with about 46% by weight of titanium dioxide by weight, and silver was deposited in an island shape on the surface by electroless plating. Particle size 5-20
90 g of a scaly powder of μm were suspended in 610 ml of water. Separately, fluorinated zirconate is produced at 0.62 g / liter in terms of zirconium and tannic acid reduction method, and trivalent chromium ions are added to the total chromium by about 20%.
% Chromate aqueous solution containing 1%
90 ml of an aqueous solution containing 0 g / l are
The solution was diluted to 90 ml, and the pH was adjusted to about 2.0 with phosphoric acid to prepare an acidic aqueous solution. This acidic aqueous solution was added to the above-mentioned amorphous alloy powder suspension and heated to 60 ° C. while continuing stirring, and this temperature was maintained for about 30 minutes. Next, the aqueous suspension was filtered, and the solid product was collected by filtration, washed with water, and dried at 120 ° C. for 3 hours.

Example 8 The surface of a mica flake was coated with about 45% by weight of titanium dioxide, and the surface was further coated with about 10% of titanium metal by sputtering to obtain a particle size of 10%. 90 g of ２０20 μm metal oxide / metal bilayer coated mica flakes were suspended in 610 ml of water. Separately,
0.62 g of fluorinated zirconate in terms of zirconium
Per liter, and an aqueous solution of chromium chromate which is produced by a tannic acid reduction method and contains about 20% of trivalent chromium ions with respect to total chromium.
Aqueous solution containing an aqueous solution having a concentration of 0 g / liter 9
0 ml was diluted to 290 ml with stirring, and phosphoric acid was added to adjust the pH to about 2.0 to prepare an acidic aqueous solution. This aqueous solution of acidic treatment was added to the suspension of mica flakes coated with the metal oxide / metal bilayer, and the mixture was heated to 60 ° C. with continuous stirring, and this temperature was maintained for about 30 minutes. Next, the aqueous suspension was filtered, and the solid product was collected by filtration, washed with water, and dried at 120 ° C. for 3 hours.

COMPARATIVE EXAMPLE 1 100 g of a metal oxide-coated mica flake having a particle size of 10 to 50 μm obtained by coating the surface of a mica flake with about 20% by weight of titanium dioxide was slurried with 1700 ml of distilled water. The pH was adjusted to 6.0 by dropwise addition of 2N sulfuric acid. Separately, 32 ml of a 5% chromic chloride (CrCl ₃ ) solution was diluted with 100 ml of distilled water. This solution was added at a constant rate to the slurry over a period of about 30 minutes. During the addition of chromic chloride, the pH was maintained at 6.0 by adding the required amount of 10% sodium hydroxide solution. After adding the entire amount of the chromic chloride solution, the slurry was filtered,
The filtrate obtained by washing with water was dried at 110 to 120 ° C for 1 hour.

Comparative Example 2 100 g of a metal oxide-coated mica flake having a particle size of 5 to 20 μm obtained by coating the surface of a mica flake with about 60% by weight of iron oxide was slurried with 1700 ml of distilled water. ,
The pH was adjusted to 6.0 by dropwise addition of 2N sulfuric acid. Separately, 32 ml of a 5% chromic chloride (CrCl ₃ ) solution was diluted with 100 ml of distilled water. This solution was added at a constant rate to the slurry over a period of about 30 minutes. During the addition of chromic chloride, the pH was maintained at 6.0 by adding the required amount of 10% sodium hydroxide solution. After the entire amount of the chromic chloride solution was added, the slurry was filtered and washed with water, and the obtained filtrate was dried at 110 to 120 ° C for 1 hour.

Comparative Example 3 The same amorphous alloy flake as the pigment used in Example 6 was washed with water and dried at 120 ° C. for 3 hours.

Comparative Example 4 A mica flake coated with the same metal oxide and metal bilayer as the pigment used in Example 5 was directly dried at 120 ° C. for 1 hour.

Comparative Example 5 A titanium dioxide / lower titanium oxide-coated mica flake having the same particle size of 10 to 50 μm as the pigment used in Example 3 was washed with water and
Dried at 20 ° C. for 3 hours.

The following tests were performed on the pigments obtained in Examples 1 to 8 and Comparative Examples 1 to 5. (1) Preparation of paint (A) Thermosetting acrylic melamine resin-based paint Thermosetting acrylic melamine resin (manufactured by Dainippon Ink, trademark: Acridic A-322, 160 parts by weight and Dainippon Ink, trademark: Super Becca Min L117-60, 3
15 parts by weight of each of the pigments of Examples 1 to 8 and Comparative Examples 1 to 5 were added to 85 parts by weight of the solid content (mixture with 4 parts by weight) to prepare 13 types of paints. (B) Thermosetting acrylic melamine resin clear paint, manufactured by Dainippon Ink, trademark: Acrydik A-310 (14
0 parts by weight) and Super Beckamine L117-60 (50 parts by weight) manufactured by Dainippon Ink, to prepare a thermosetting acrylic melamine resin-based clear paint. (C) Two-part curable acrylic urethane resin base paint Two-part curable acrylic urethane resin (manufactured by Dainippon Ink, trademark: Acrydik 54-480, 100 parts by weight, Mitsui Toatsu, trademark: Olester NP-1000) , 20 parts by weight) of the above pigment 1
13 parts of paints were prepared by adding 5 parts by weight. (D) Two-component curable acrylic urethane resin-based clear paint Dainippon Ink, trademark: Acrydik 54-480 (1
00 parts by weight) and Mitsui Toatsu, trademark: Olestar NP-
1000 (20 parts by weight) to prepare a two-part curable acrylic urethane resin clear coating.

(2) Preparation of performance test plate A cold-rolled steel plate (size = 70 × 150 mm) was subjected to an automotive coating pretreatment by a conventional method, and then was subjected to cation electrodeposition and intermediate coating sequentially to obtain 52 sheets. An intermediate coated plate was produced. Next, the acrylic melamine resin-based base paint (A), which was formed as described above, was further applied to 26 plates among them so as to have a dry film thickness of 15 μm. More wet
An acrylic melamine resin clear paint (B) is applied by an on-wet method so as to have a dry film thickness of 35 μm,
Heating and curing at 145 ° C. for 30 minutes produced two test plates each. Similarly, 13 kinds of acrylic urethane resin-based base paints (C) were applied so as to have a dry film thickness of 15 μm, respectively, and an acrylic urethane resin-based clear paint (D) was applied thereto by a wet-on-wet method. 3
The mixture was applied to a thickness of 5 μm, heated at 80 ° C. for 30 minutes, and cured to prepare two types of 13 types of test plates.

(3) Performance Test Conditions (A) High-Temperature Water Resistance Test Half of the lengthwise half of each of the 26 types of test plates (13 types of coating A / B, 13 types of coating C / D) prepared as described above were tested. After immersion in warm water at 80 ° C. for 24 hours, changes in the painted surface between the immersed portion and the unimmersed portion were visually determined. (B) Accelerated weathering test For each of the 26 types of test plates similar to the above, an accelerated weathering test was performed with a sunshine weatherometer at 1000 times.
After the test, the gloss retention (ΔG) before and after the test, the color difference (ΔG)
E) was measured. Table 1 shows the results of the high-temperature water resistance test and the accelerated weather resistance test.

[0050]

[Table 1]

As shown in Table 1, the glossy flaky pigments obtained in Examples 1 to 8 of the present invention showed remarkably good results in the high-temperature water resistance test and the accelerated weather resistance test. On the other hand, Comparative Examples 1 to 5 are remarkably inferior to the Examples in the high-temperature water resistance test and the accelerated weather resistance test, and it can easily be inferred that they cannot be used under severe conditions such as painting the outer surface of an automobile body. Furthermore, the comparative examples 1 to 5 also require complicated chemical liquid management in the manufacturing process, while the examples 1 to 8 according to the present invention have the advantage that a good product can be obtained by a simple method. it is obvious.

[0052]

Industrial Applicability The flaky composite pigment of the present invention has a durable luster having extremely excellent high-temperature water resistance and weather resistance, and is useful for paints for automobile body outer surfaces and other uses. . Further, according to the production method of the present invention, a flaky composite pigment having a durable gloss can be efficiently produced.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09C 1/64 C09C 1/64 (72) Inventor Hiroshi Ito 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) References JP-A-63-130673 (JP, A) JP-A-61-295234 (JP, A) JP-A-58-219266 (JP, A) JP-B-43-25644 (JP, B1) (58) Survey Field (Int.Cl. ⁶ , DB name) C09C 3/06 C09C 1/24 C09C 1/40 C09C 1/62 C09C 1/64

Claims (5)

(57) [Claims] 1. A substrate (A) composed of flaky inorganic pigment particles and a composite film covering the surface of the substrate (A) composed of the flaky inorganic pigment particles and comprising a zirconium / chromium-containing composite material A substrate (A) comprising a layer (B) and comprising the flaky inorganic pigment particles, wherein (1) a surface of a core comprising the inorganic flaky particles is at least selected from a metal, an alloy and a metal oxide; (2) The surface of a core body composed of inorganic flaky particles is formed of at least one metal or alloy film layer and at least one metal oxide film layer. A powder coated with a surface layer formed by laminating in any order; (3) (i) a core made of inorganic flaky powder; and (ii)
The surface of the core made of inorganic flaky powder is at least one type selected from a composite core coated with a metal oxide film layer, and at least one type selected from metals and alloys. A powder in which a plurality of coating layers are formed in an island-like manner; and in each of the powders (1), (2) and (3), the inorganic scaly powder The core body composed of particles comprises at least one selected from the group consisting of (a) mica flakes, (b) aluminum flakes, (c) amorphous alloy flakes, and (d) mica-like iron oxide (MIO) powder. A flaky composite pigment having a durable gloss. 2. A weight ratio (A) / (base) of the substrate (A) comprising the flake-like inorganic pigment particles and the composite coating layer (B).
(B) is 1000 / 0.2 to 1000/20,
The flaky composite pigment according to claim 1. 3. The substrate (A) comprising the flaky inorganic pigment particles according to claim 1, comprising at least one zirconium ion supplying compound and at least one trivalent chromium ion supplying compound, and Suspended in an aqueous acidic treatment solution having a pH value of 1.0 to 5.0, and suspending the suspension at 20 to 90.
C. to form a composite coating layer (B) made of a zirconium / chromium-containing composite material on the surface of the flaky inorganic pigment particles by heat treatment, and the flaky powder obtained by the heat treatment , Washing and drying, and drying the scaly composite pigment having a durable luster. 4. The method according to claim 1, wherein the acidic aqueous solution is treated with at least one selected from inorganic acids and organic acids.
4. The method according to claim 3, wherein the pH is adjusted to a pH value of ~ 5.0. 5. The method according to claim 3, wherein the drying is performed at a temperature of 300 ° C. or less.