JP2743298B2 - Method for producing bismuth vanadate composition for pigments - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bismuth vanadate composition for pigments and a method for producing the same, and more particularly, to the use of a conventional yellow pigment because of its high purity (intensity), coloring power and hiding power. Fields, for example,
An object of the present invention is to provide a yellow-based bismuth vanadate pigment composition useful in the fields of coloring of general resins and engineering plastic resins, paints, inks, ceramics, building materials, and the like.

[0002]

2. Description of the Related Art Yellow pigments widely used at present include inorganic pigments such as cadmium sulfide, lead chromate, titanium yellow and iron oxide yellow, and organic pigments such as azo pigments and quinacridone. There are high-grade pigments. However, cadmium sulfide and lead chromate are
Although excellent in terms of coloring density and hiding power, there is a problem with toxicity and its use is limited. This trend is expected to continue in the future. Although titanium yellow has high resistance and hiding properties, it is inferior in color purity and coloring power to the former two, and the field of use is similarly limited. In addition, iron oxide yellow,
Poor in purity, coloring power and heat resistance. Organic pigments such as azo pigments generally have higher purity and coloring power than inorganic pigments, but are inferior in hiding power and various resistances. In addition, the bleeding resistance is often poor.

[0003]

SUMMARY OF THE INVENTION The present invention has been made with the above-mentioned problems in mind. That is, among the yellow pigments, titanium yellow and iron oxide yellow do not have the same high purity and coloring power as organic pigments in terms of color tone. Although there is an acid-based pigment, its use is limited in terms of toxicity, and a pigment that substitutes it is desired in the market. Similarly, yellow pigments are demanded in fields requiring use under high resistance, which cannot be expected with organic pigments, and fields requiring stability against organic solvents.

Further, many studies have been made on bismuth vanadate alone, which is the parent of the pigment of the present invention. For example, Japanese Patent Application Laid-Open Nos. 52-156800 and 53-3
No. 6527, JP-A-55-78063, JP-A-63-162765, etc., and attempts have been made to improve the color tone and various resistances, but it is difficult to find a practical product. It is. Accordingly, an object of the present invention is to provide high purity (intensity), coloring power, hiding power, and fields used in conventional yellow pigments, for example, coloring of general resins and engineering plastic resins, paints, An object of the present invention is to provide a yellow-based bismuth vanadate pigment composition useful in fields such as inks, ceramics, and building materials.

[0005]

The above object is achieved by the present invention described below. That is, the present invention relates to zirconium,
In the production of pigment compositions consisting of smas and vanadium
To precipitate from the zirconium salt solution and the alkaline solution.
The system containing the precipitate and the bismuth salt solution
Simultaneous addition of an alkaline solution of indium causes precipitation.
A method for producing a yellow pigment for bismuth vanadate composition characterized by that.

[0006]

According to the present invention, as a result of intensive research to meet the above-mentioned demand, a salt solution of zirconium and an alkaline solution are prepared by a wet method.
Bismuth was added to the system containing the zirconium precipitate formed in
Simultaneously add the salt solution and the alkaline aqueous solution of vanadium.
By producing a precipitate by heating and aging, it has a clear color tone, large coloring power and high fastness that can not be produced with bismuth vanadate alone, and also cadmium pigment and lead chromate pigment It has been found that a pigment composition having the same properties as in Example 1 can be obtained. The zirconium-coexisting bismuth vanadate-based pigment composition according to the present invention has high purity in a color tone not found in a single product, coloring power, and hiding power.
It sufficiently satisfies the above-mentioned demand, and is useful for use under high resistance or under an organic solvent.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention is described in more detail with reference to preferred embodiments. The bismuth vanadate-based pigment composition of the present invention is a salt of zirconium in a wet method.
A precipitate is formed between the solution and the alkaline solution, and the precipitate is contained.
An aqueous solution of a bismuth salt and an aqueous solution of an alkali vanadium are simultaneously mixed with the precipitated water, and each element is precipitated in a desired ratio, followed by filtration, washing with water and drying.
The essence of the present invention is basically to have no suitability as a pigment, to bismuth vanadate, by mixing zirconium to a desired ratio in a wet process to constitute a desired pigment composition, At that time, by heating and aging, the characteristics can be made more reliable. By mixing zirconium according to the present invention, bismuth vanadate alone can provide more reliable pigment suitability that can withstand actual use, and specifically has higher purity and coloring power and various resistances. Can be given.

[0008] As a raw material of the constituent elements used in the present invention, salts of the respective elements can be used. When using a salt of bismuth and zirconium, with an alkaline precipitating agent, such as sodium hydroxide or soda ash, also the following sequence of elements of each component by a wet with alkaline solution of vanadium
Is incidentally precipitation, uniformly mixed can be obtained the desired product. As the vanadium as a raw material, an alkali salt of vanadic acid such as Na ₃ VO ₄ can be used, and V ₂ O
₅ can be dissolved in an alkali such as caustic soda and used as an aqueous alkali solution. In the above, the ratio of each element is zirconium: bismuth: vanadium in a molar ratio of 0.1 to 1.5: 1: 1, preferably 0.25 to 1.
A ratio of 0: 1: 1 is appropriate, and an effective effect can be exhibited if the proportion of zirconium to be mixed is 0.1 mol or more. On the other hand, if it exceeds 1.5 mol, the coloring density is lowered, and a color tone having a satisfactory color tone cannot be obtained.

The bismuth salt solution concentration is preferably about 0.5 mol / l to 1.0 mol / l.
If the concentration is lower than that, not only will the workability worsen,
Since bismuth salts are easily hydrolyzed, it is necessary to increase the acidity using commonly used inorganic acids such as nitric acid, sulfuric acid, and hydrochloric acid, and the ratio of this acid depends on the amount of water added to bismuth. At lower concentrations, more acid is needed. In some cases, it is more reasonable to use the zirconium salt by mixing it with a bismuth salt, but in such a case, there is no problem if the concentration of the mixed solution is within a range where each salt does not precipitate. In the case of vanadium, there is no particular problem unless the concentration of the alkaline solution is extremely low.
A range of 1 mol / l to 0.5 mol / l is suitable.

In the above-mentioned salt solution, first, a predetermined amount of a zirconium salt solution and a solution of caustic soda are simultaneously dropped into a previously prepared sediment water to form a zirconium precipitate. At this time, the pH at which zirconium precipitates
There is no particular problem as long as it is in the H region. However, considering the adverse effect of the formed basic salt, it is preferably carried out at around pH = 7.

Next, a bismuth salt solution and a vanadium alkali solution, which are blended in a ratio of bismuth: vanadium = 1: 1, are simultaneously dropped into the precipitation water. It is more effective to carry out the pH at around pH = 7 as in the case of zirconium. After forming a precipitate with stirring for 30 minutes to 1 hour in this manner, the mixture is heated and aged at 90 to 100 ° C. for 3 to 6 hours to complete the color tone and various properties. Can be completed. If the aging temperature at this time is too low, the crystallization of bismuth vanadate will be slow, which is wasted time and the desired properties will not be sufficiently exhibited. The order of dropping, it is important Succoth overlooked earlier zirconium as described above, in the method in which generating a stretch precipitate at high turbulence, uniformity of microscopic mixing can not be guaranteed and therefore Crystal growth during ripening slows down and requires heat treatment to achieve this,
Disorder in the atomic arrangement of the pigment composition in such a method in a microscopic manner is a major cause of deterioration of various resistances in a solvent or a resin.

Next, the co-precipitated precipitate is used to remove residual salts.
By sufficiently washing with water and filtering to an electric conductivity of about 300 μM, the water content becomes 40% by weight to 80% by weight.
% By weight and dried at a temperature of about 100 ° C. to 120 ° C. to obtain the bismuth vanadate-based pigment composition of the present invention. The zirconium-coexisting bismuth vanadate pigment composition thus obtained is excellent in color tone and various resistances compared to bismuth vanadate alone. In this state, there is no problem under normal use even in this state, but by performing the heat treatment continuously, zirconium is dissolved in the base of bismuth vanadate, and various resistances are further ensured. Heat treatment at 300-600 ° C
It is preferable to carry out the treatment for about a time, and if the temperature is lower than that, no improvement in characteristics is observed. If the temperature is higher than that, sintering tends to take place, and the color density and dispersibility decrease. The zirconium-dissolved bismuth vanadate-based pigment composition thus obtained was more excellent in color tone and various resistances than the unheated product.

[0013]

Next, the present invention will be described more specifically with reference to examples and comparative examples. In the following, "parts" and "%" are based on weight unless otherwise specified. Example 1 16.11 parts of zirconyl oxychloride hexahydrate and dissolved water 10
0 parts with each other to prepare a zirconium salt solution. Next, 4.5 parts of caustic soda and 100 parts of water are weighed as the precipitant to prepare an alkaline solution. These are simultaneously added to 800 parts of previously prepared precipitation water at pH = 7 in about 30 minutes to precipitate a zirconium precipitate.

The product is subsequently treated with bismuth nitrate pentahydrate 9
Bismuth nitrate acidic aqueous solution obtained by mixing 7.02 parts, 42 parts of concentrated nitric acid and 200 parts of water and 18.2 parts of vanadium pentoxide,
It is subjected to simultaneous addition with an alkaline solution of vanadium in which 42.5 parts of caustic soda and 280 parts of water are mixed. The precipitation reaction is carried out at pH = 7 over about 30 minutes. At this time, the color of the precipitate changes from nearly transparent white to slightly reddish yellow. This is subsequently aged with stirring at 90 ° C. for 3 hours to make the reaction more complete.
At this time, the precipitate gradually grows as monoclinic crystals,
The tone becomes clearer. The precipitate formed is thoroughly washed with water, filtered, and dried at a temperature in the range of 100 ° C to 120 ° C. The pigment of the present invention thus obtained was subjected to a coloration test, a weather resistance and a heat resistance test according to the methods described below.
And the result of Table 2 was obtained.

Example 2 32.22 parts of zirconyl oxychloride hexahydrate and dissolved water 10
0 parts with each other to prepare a zirconium salt solution. Next, 9.0 parts of caustic soda and 100 parts of water are weighed as the precipitant to prepare an alkaline solution. These are simultaneously added to 800 parts of previously prepared precipitation water at pH = 7 for about 20 minutes to precipitate a zirconium precipitate. The precipitate thus obtained was then subjected to pigment synthesis in the same manner as in Example 1, and the obtained pigment was obtained as shown in Tables 1 and 2 below.

EXAMPLE 3 64.44 parts of zirconyl oxychloride hexahydrate and 20 parts of dissolved water
0 parts with each other to prepare a zirconium salt solution. Next, 18.0 parts of caustic soda and 200
Weigh the parts and prepare an alkaline solution. These were placed in 800 parts of previously prepared precipitation water for about 20 minutes at pH = 7.
At the same time to precipitate a zirconium precipitate. The precipitate thus obtained was then subjected to pigment synthesis in the same manner as in Example 1, and the obtained pigment was obtained as shown in Tables 1 and 2 below.

Comparative Example 1 An acidic aqueous solution of bismuth nitrate obtained by mixing 97.02 parts of bismuth nitrate pentahydrate, 42 parts of concentrated nitric acid and 200 parts of water, 18.2 parts of vanadium pentoxide, 42.5 parts of caustic soda and water 2
Prepare an alkaline solution of vanadium mixed with 80 parts,
It is added simultaneously to 800 parts of previously prepared precipitation water. This precipitation reaction is carried out for about 30 minutes by adding at pH = 7. At this time, the color of the precipitate changes from nearly transparent white to slightly red. This is subsequently aged with stirring at 90 ° C. for 3 hours to make the reaction more complete.
At this time, the precipitate gradually grows as monoclinic crystals,
The tone becomes clearer. The precipitate formed is thoroughly washed with water, filtered, and dried at a temperature in the range of 100 ° C to 120 ° C. The pigments of Comparative Examples obtained in this manner were subjected to a coloration test and a weather resistance test according to the methods described below, and Tables 1 and 2 below were used.
Was obtained.

Coloring test The obtained pigment composition was dispersed in a melamine alkyd resin at 40 PHR using a paint shaker to prepare a paint, which was applied to a black band art paper using a 6 mil applicator to adjust the color tone. Observed. Further, the color purity was measured with a colorimeter, and the difference from the comparative example was examined. The tinting strength was determined by using commercially available titanium oxide at Pig / TiO ₂ = 1/9, and the color tone, purity, and coloring density were observed as in the case of the dark color. Weather resistance test The obtained pigment composition was dispersed in a melamine alkyd resin at 40 PHR with a paint shaker to prepare a coating, applied to an aluminum coated plate, and exposed to a super UV weathering accelerator for 80 hours. The ΔE ^* values before and after acceleration were measured by colorimetry, and the difference was observed.

[0019]

[Table 1]

[0020]

[Table 2]

Example 4 The dried pigment obtained in Example 1 is heat-treated at 500 ° C. for 1 hour in an ordinary electric furnace in air. The pigment obtained in this manner had a sharper color tone, and was subjected to a coloration test, a weather resistance and a heat resistance test according to the methods described below, and the results shown in Tables 3 to 5 below were obtained. Comparative Example 2 The dried pigment obtained in Example 1 was subjected to a coloring test, a weather resistance and a heat resistance test according to the methods described below, and the results as shown in Tables 3 to 5 below were obtained. Coloring test : The pigment composition obtained was melamine-coated with a paint shaker.
The composition was dispersed in an alkyd resin at 40 PHR to prepare a paint, which was applied to art paper with a black belt using a 6 mil applicator, and the color tone was observed. Further, the color purity was measured with a colorimeter, and the difference from the comparative example was examined.

Weather resistance test : The obtained pigment composition was dispersed in a melamine alkyd resin with a paint shaker at 40 PHR, a coating was prepared, applied to an aluminum coated plate, and exposed to a super UV weathering accelerator for 80 hours. Before and after promotion by colorimetry.
The E ^* values were measured and differences were observed. Heat resistance test : The obtained pigment composition was sufficiently mixed with pigment composition: zinc stearate = 4: 1, and added to a high-density polyethylene resin at 0.5 PHR.
After holding at 10 ° C., 240 ° C., and 280 ° C. for 10 minutes, injection molding was performed, and the degree of discoloration of the molded product was measured and evaluated by ΔE ^* value.

[0023]

[Table 3]

[Table 4]

[0024]

[Table 5]

[0025]

According to the present invention as described above, it has high purity (intensity), coloring power and hiding power, and is used in the fields used for conventional yellow pigments, for example, general resins and engineering plastic resins. A yellow-based bismuth vanadate pigment composition useful in the fields of coloring, paints, inks, ceramics, building materials, and the like can be provided.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Akira Nishio, Inventor 1-7-6 Nihombashi Bakurocho, Chuo-ku, Tokyo Inside Dainichi Seika Kogyo Co., Ltd. (72) Mineki Machitori 1-7 Nihonbashi Bakurocho, Chuo-ku, Tokyo No. 6 in Dainichi Seika Kogyo Co., Ltd. (56) References JP-A-3-227373 (JP, A) JP-A-4-321520 (JP, A)

Claims (4)

(57) [Claims] 1. Zirconium, bismuth and vagadium
In the production of a pigment composition comprising a zirconium salt
A precipitate is formed from the solution and the alkaline solution, and the precipitate is formed.
Bismuth salt solution and vanadium alkaline solution
A method for producing a yellow-based bismuth vanadate composition for a face, wherein a precipitate is formed by simultaneously adding a compound. 2. The process for producing a yellow bismuth vanadate composition for a pigment according to claim 1 , wherein the precipitate is aged while heating and stirring at 90 to 100 ° C. after the precipitation. 3. The process for producing a yellow bismuth vanadate composition for a pigment according to claim 2 , wherein the aging time after the precipitation is 3 to 6 hours. 4. The process for producing the pigment for yellow bismuth vanadate composition according to claim 1 which is heat-treated precipitate at a temperature of 300 to 600 ° C..