JP2020011888A - Burned composition and method for producing the same, and electrodeposition-coating material - Google Patents

Abstract

To provide an electrodeposition-coating technique capable of performing a baking process at relatively low temperature.SOLUTION: This invention relates to a burned product comprising a zinc compound and a bismuth compound, wherein: a relation of weight percent Wz of zinc oxide and a weight percent Wb of bismuth oxide and/or bismuth hydroxide is Wz≥Wb; and the burned product is used as an anti-rust agent and/or a hardening catalyst. A fatty acid bismuth, especially bismuth trioctylate or a mixture of the bismuth trioctylate and ethylene diamine, is added to the burned product, thereby lowering a baking or hardening temperature to about 130°C effectively.SELECTED DRAWING: None

Description

  The present invention relates to a technique relating to a novel baked composition useful for coating, and can further reduce the curing temperature while avoiding the use of an organotin compound, and is excellent in rust prevention. Related to the technology that can be provided.

  In general, electrodeposition coating, in which coating is performed electrochemically, has excellent corrosion resistance and throwing power, and is widely used for coating automobile bodies and parts. The coating process usually covers two to three steps (for example, three steps of undercoating-intermediate coating-overcoating). In the first-stage undercoating process, the adhesiveness or adhesion between the paint and the surface to be coated is improved, and effective rust prevention is provided. Then, an aesthetically pleasing painted surface is obtained by the intermediate coating and the top coating in the next stage. See Non-Patent Document 1 for the general background of electrodeposition coating.

  The coating composition used for the electrodeposition coating usually contains a coloring pigment, a rust inhibitor and other additives in addition to the resin. Focusing on rust preventives, the most excellent rust preventives are lead compounds such as lead chromate, lead silicate and lead acetate. However, these lead compounds are harmful and their use is problematic. The inventors have previously proposed a specific fired composition as a material replacing the lead compound. That is, it is a technique disclosed in Patent Document 1, in which a specific fired composition obtained by firing a zinc compound and a tin compound is blended in an electrodeposition paint to not only have excellent anticorrosion properties but also to stabilize an electrodeposition bath. The technology is also good.

Japanese Patent No. 4204049

Automotive electrodeposition coating technology, iron and steel, 66 (1980) No. 7, pp. 185-195

  In the electrodeposition coating, the coating is strengthened by performing a baking process after the electrodeposition coating. The baking temperature is, for example, 150 ° C. or higher. Since this high temperature may cause thermal distortion or the like in the product to be coated, it is desired to reduce the temperature if possible. The temperature reduction is preferable from the viewpoint of saving energy used, environmentally and economically. However, the baking composition proposed above cannot obtain sufficient curing by baking at a temperature lower than 150 ° C., and cannot obtain good coating smoothness.

  Further, a curing catalyst is used in the coating composition in order to accelerate the curing of the coating film. As the curing catalyst, an organic tin compound such as dioctyltin oxide (DOTO) has been used. However, organotin compounds are strictly regulated from the viewpoint of environmental protection. Therefore, a direction in which such a problematic curing catalyst is not used as much as possible is desired.

  Therefore, an object of the present invention is to provide a technique of utilizing firing, which can reduce the firing temperature from 150 ° C.

  Another object of the present invention is to provide a coating technique utilizing sintering, which can obtain a sufficient curing catalyst ability without using a curing catalyst which is a problem in terms of environmental conservation. Further objects of the present invention will become clear from the description hereinafter.

The inventors have found a new firing composition that is useful for enhancing rust prevention and curability while assuming that firing technology is utilized.
The first fired composition is a fired product of a zinc compound and a bismuth compound, and the weight% Wz of zinc oxide and the weight% Wb of bismuth oxide or / and bismuth hydroxide have a relationship of Wz ≧ Wb, Moreover, it is a rust inhibitor and / or a curing catalyst.

  The second fired composition is a fired product of a zinc compound, a bismuth compound, and a silicon compound, and the weight% Wz of zinc oxide, the weight% Wb of bismuth oxide or / and bismuth hydroxide, and the weight of silicon oxide % Ws and Wz ≧ Wb, Ws (where Wz ≧ Wb, Ws means Wz ≧ Wb and Wz ≧ Ws), and be a rust inhibitor and / or a curing catalyst. It is characterized by. The second fired composition further includes silicon oxide with respect to the first fired composition. Accordingly, due to the bulkiness or volume increase of silicon oxide, there are some difficulties in producing a large amount of the fired composition as compared with the production of the first fired composition in terms of equipment and handling. Stated differently, the first fired composition is advantageous in manufacturing.

  Further, the third fired composition is a fired product of a zinc compound, a titanium compound and a silicon compound, and the weight% Wz of zinc oxide, the weight% Wt of titanium oxide and the weight% Ws of silicon oxide are Wz ≧ Wt. , Ws (here, Wz ≧ Wt, Ws means Wz ≧ Wt and Wz ≧ Ws), and is a rust inhibitor or / and a curing catalyst. The titanium oxide in the third fired composition and the bismuth oxide in the first and second fired compositions are common in that they are transition metal oxides having d electrons that govern physical properties, and are fired. It is considered that they exhibit similar physical properties.

Here, specific examples of the zinc compound, the bismuth compound, the silicon compound, and the titanium compound are as follows.
Zinc compound:
Zinc oxide, zinc hydroxide, zinc carbonate, zinc phosphate, zinc chloride, zinc nitrate, zinc acetate and the like.
Bismuth compounds:
Bismuth oxide, bismuth hydroxide, basic bismuth carbonate, bismuth phosphate, bismuth chloride, bismuth oxychloride bismuth nitrate, bismuth stannate, bismuth vanadate, bismuth zirconate, bismuth titanate, bismuth acetate, bismuth octylate, oxalic acid Bismuth, bismuth citrate, bismuth hypogallate, basic bismuth salicylate, bismuth tri (dimethyldithiocarbamate), aluminum bismuth triabietate, bismuth trinedecanoate, bismuth tris (2-ethylhexanoate), tris Bismuth methanesulfonate, magnesium bismuth aluminosilicate, bismuth tetraoxovanadate, bismuth tris [2,2-dialkylalkanoate (C10)], bismuth tris (methanesulfonic acid), bismuth tritartrate, dilactic acid Bismuth, and the like.
Silicon compound:
Examples include silicon dioxide, silicon tetrachloride, tetramethoxysilane, and trimethylsilyl chloride.
Titanium compound:
Examples include titanium oxide, titanium hydroxide, titanium tetrachloride, titanium tetraacetate, and tetraisopropoxy titanium.

  Each of the first to third firing compositions of the present invention can be manufactured by mixing a powder mixture of each material with a solvent such as ethanol, and firing the mixture at 300 ° C to 1000 ° C in an electric furnace.

  Each of such fired compositions can be usefully used as a material for the composition of an electrodeposition paint, specifically, a cationic electrodeposition paint (corrosion inhibitor or rust inhibitor). Further, it can be provided as an electrodeposition paint containing the same. When these fired compositions are used as a composition for electrodeposition coating, there is no particular restriction on handling, and the firing can be performed in the same manner as in a usual pigment dispersion method. For example, a dispersion paste can be prepared by previously dispersing each of the firing compositions in a resin for dispersion, and can be blended. Examples of the pigment dispersing resin include epoxy quaternary ammonium salt type resins and acrylic quaternary ammonium salt type resins which are usually used for cationic electrodeposition coatings.

  As the base resin, those having a number average molecular weight of 100 to 10,000, preferably 1,000 to 3,000 derived from a bisphenol-type epoxy resin can be used, and the base equivalent of the base resin is 40 to 150 (milliequivalent / 100 g); Preferably, it is 60 to 100 (meq / 100 g).

  As the crosslinking agent, a blocked polyisocyanate compound is used. The blocked isocyanate crosslinking agent can be obtained by an addition reaction between a blocking agent for isocyanate and a polyfunctional isocyanate. Desirably, the isocyanate blocking agent regenerates a free isocyanate group by dissociating the block when heated to 100 to 200 ° C. For example, caprolactam, phenol, ethanol, 2-ethylhexyl alcohol, butyl cellosolve, methyl ethyl ketoxime and the like. In addition, as the polyfunctional isocyanate compound, a fatty acid, an alicyclic or aromatic polyisocyanate is used. Examples thereof include tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and isocyanates thereof.

<Basic concept of curing catalyst ability>
Each of the first to third fired compositions of the present invention not only functions as a rust inhibitor, but also functions as a curing catalyst. However, it is effective to additionally add a known curing catalyst in order to further enhance the rust prevention property and the curability. By adding a fatty acid bismuth, particularly a bismuth trioctylate, the curing temperature can be more effectively lowered, for example, to about 130 ° C., and at the same time, the rust prevention can be further enhanced.
<Preferred examples of curing catalyst to be added>
As a curing catalyst to be added, fatty acid bismuth (preferably, C _4-15 fatty acid bismuth), particularly bismuth trioctylate can be used alone. However, by using a mixture of bismuth trioctylate and ethylenediamine, trioctyl can be used. The use amount of bismuth acid can be reduced. Specifically, it has the following form.
(1) A mixture of tris (2-ethylhexanoate) bismuth and N, N, N ', N'-tetrakis (2-hydroxyethyl) ethylenediamine.
(2) A mixture of tris (2-ethylhexanoate) bismuth and N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine.
(3) A mixture of trinedecanoate bismuth and N, N, N ', N'-tetrakis (2-hydroxyethyl) ethylenediamine.
(4) a mixture of trineodecanoate bismuth and N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine.

  Neutralization and water-solubilization of the electrodeposition coating composition of the present invention are performed by dispersing a base resin and a blocked isocyanate crosslinking agent in an aqueous medium using an organic acid such as formic acid, acetic acid, propionic acid, lactic acid, and sulfamic acid as a neutralizing agent. It is done by doing.

  In the electrodeposition coating composition of the present invention, as a coating additive, for example, a pigment such as titanium white, carbon black, talc, clay, or silica can be dispersed in a pigment dispersing resin and added as a pigment paste. If necessary, other rust-preventive pigments, for example, aluminum phosphate, aluminum phosphomolybdate, barium metaborate, etc., and a coating additive such as a surface conditioner or an organic solvent can be blended.

  The electrodeposition coating composition of the present invention is applied to the surface of a substrate by cationic electrodeposition coating. The cationic electrodeposition coating composition is prepared by adjusting the solid content concentration to 15 to 25% by weight with deionized water and the pH of the electrodeposition coating composition adjusted to the range of 5.5 to 7.0. The reaction is carried out at a temperature of 20 to 30 ° C and a voltage of 100 to 400V.

The film thickness of the coating film formed using the electrodeposition coating composition of the present invention is, for example, 10 to 50 μm, and the baking temperature of the coating film is, for example, 130 ° C. to 150 ° C. In the technique of utilizing the fired product proposed earlier, when baked at 150 ° C. or 130 ° C., a pear-shaped projection appeared on the painted surface, and the smoothness was lost. However, by utilizing the present invention, good coating smoothness can be obtained even at a low baking temperature of 130 ° C.
Hereinafter, the present invention will be described more specifically with reference to Production Examples and Examples.
[Production Example 1]

In a 500 ml beaker, 76 g of zinc oxide, 4 g of bismuth hydroxide and 20 g of silicon oxide are weighed and dispersed by adding a mixed solvent of 176 ml of ethanol, 20 ml of isopropyl alcohol and 4 ml of methyl ethyl ketone. Mix for 24 hours using a ball mill. Thereafter, the mixture is transferred to an eggplant flask and the solvent is removed under reduced pressure using a rotary evaporator to obtain a powder mixture of zinc oxide, bismuth hydroxide, and silicon oxide. The obtained powder mixture was heated from 20 ° C. to 10 ° C./min in a high-speed heating electric furnace (box furnace KBF848N2 / manufactured by Koyo Lindberg K.K.) and calcined at 800 ° C. for 1 hour to obtain a white calcined product. The composition of the obtained white fired product was zinc oxide / bismuth oxide / silicon oxide = 73.7 / 6.9 / 19.4% by weight (theoretical value: zinc oxide / bismuth oxide / silicon oxide = 73/7/20% by weight). 90 g of butyl acetate is added to 10 g of the white fired product, and the mixture is dispersed with a paint shaker for 5 hours to obtain 100 g of a 10% solid solution of Production Example 1.
[Production Example 2]

By adding and mixing 100 g of the 10% solid solution of Production Example 1 described above to 34 g of the 10% solution described in E2 below, 134 g of the calcined product of Production Example 1 and a 10% solution of bismuth trioctylate at a weight ratio of 7.5 / 2.5 were obtained. obtain. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 2.
[Production Example 3]

By mixing 34 g of the bismuth trioctylate 10% solid solution described in E2 with 34 g of the calcined product 10% solid solution of Production Example 1, 68 g of a 5/5 weight ratio of a 10% solution is obtained. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 3.
[Production Example 4]

In the same manner, by mixing 6.8 g of a 10% solid solution of the calcined product of Production Example 1 with 20 g of a 10% solid solution of bismuth trioctylate, a 10% solution having a 2.5 / 7.5 weight ratio is obtained. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 4.
[Production Example 5]

In a 500 ml beaker, 60 g of zinc oxide, 20 g of titanium oxide and 20 g of silicon oxide are weighed, and a mixed solvent of 176 ml of ethanol, 20 ml of isopropyl alcohol and 4 ml of methyl ethyl ketone is added and dispersed. Mix for 24 hours using a ball mill. Thereafter, the mixture is transferred to an eggplant flask and the solvent is removed under reduced pressure using a rotary evaporator to obtain a powder mixture of zinc oxide, bismuth hydroxide, and silicon oxide. The obtained powder mixture was heated from 20 ° C. to 10 ° C./min in a high-speed heating electric furnace (box furnace KBF848N2 / manufactured by Koyo Lindberg K.K.) and calcined at 800 ° C. for 1 hour to obtain a white calcined product. The composition of the white fired product was zinc oxide / titanium oxide / silicon oxide = 59.6 / 20.1 / 20.3% by weight (theoretical value: zinc oxide / titanium oxide / silicon oxide = 60/20/20% by weight). 90 g of butyl acetate is added to 10 g of the obtained white fired product, and the mixture is dispersed with a paint shaker for 5 hours to obtain 100 g of a 10% solid solution of Production Example 5.
[Production Example 6]

By mixing 100 g of a 10% solid solution of the fired product of Production Example 5 with 34 g of a 10% solid solution of bismuth trioctylate described in E2, 134 g of a 10% solution of the fired product of Production Example 1 and a bismuth trioctylate 7.5 / 2.5 weight ratio is obtained. . Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 6.
[Production Example 7]

34 g of a 10% solid solution of bismuth trioctylate is mixed with 34 g of a 10% solid solution of the calcined product of Production Example 5 to obtain 68 g of a 5/5 weight ratio of a 10% solution. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 7.
[Production Example 8]

By mixing 6.8 g of a 10% solid solution of the calcined product of Preparation Example 5 with 20 g of a 10% solid solution of bismuth trioctylate, 26.8 g of a 10% solution having a 2.5 / 7.5 weight ratio is obtained. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 8.
[Production Example 9]

In a 500 ml beaker, weigh 60 g of zinc oxide and 60 g of bismuth hydroxide, add and disperse a mixed solvent of 176 ml of ethanol, 20 ml of isopropyl alcohol and 4 ml of methyl ethyl ketone. Mix for 24 hours using a ball mill. Thereafter, the mixture is transferred to an eggplant flask and the solvent is removed under reduced pressure using a rotary evaporator to obtain a powder mixture of zinc oxide and bismuth hydroxide. The obtained powder mixture was heated from 20 ° C. to 10 ° C./min in a high-speed electric furnace (box furnace KBF848N2 / manufactured by Koyo Lindberg Co., Ltd.) and calcined at 800 ° C. for 1 hour to obtain a slightly yellow calcined product. . The composition of the slightly yellow fired product was zinc oxide / bismuth oxide = 51.8 / 48.2% by weight (theoretical value; zinc oxide / bismuth oxide = 52.7 / 47.3% by weight). 90 g of butyl acetate is added to 10 g of the obtained slightly yellow fired product, and the mixture is dispersed with a paint shaker for 5 hours to obtain 100 g of a 10% solid solution of Production Example 9.
(Production Example 10)

By mixing 100 g of a 10% solid solution of the baked product of Production Example 9 with 34 g of a 10% solid solution of bismuth trioctylate described in E2, 134 g of a 10% solution of the baked product of Production Example 9 and a bismuth trioctylate 7.5 / 2.5 weight ratio is obtained. . Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 10.
(Production Example 11)

34 g of a 10% solid solution of bismuth trioctylate and 34 g of a 10% solid solution of the calcined product of Production Example 9 are mixed to obtain 68 g of a 5/5 weight ratio of a 10% solution. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 11.
(Production Example 12)

By mixing 6.8 g of a 10% solid solution of the calcined product of Production Example 9 with 20 g of a 10% solid solution of bismuth trioctylate, 26.8 g of a 10% solution having a 2.5 / 7.5 weight ratio is obtained. Subsequently, the solution is concentrated under reduced pressure and dried to obtain the composition of Production Example 12.
[E1 (Preparation of DOTO 5% solution)]

285 g of butyl acetate is added to 15 g of dioctyltin oxide (DOTO), and the mixture is dispersed with a paint shaker for 5 hours to obtain 300 g of a 5% solution.
[E2 (Preparation of bismuth trioctylate 10% solution)]

270 g of butyl acetate is added to 30 g of bismuth trioctylate (BiCAT, manufactured by 8210 Shepherd) and dispersed with a paint shaker for 5 hours to obtain 300 g of a 10% solution.
[Curability test-1 (gel fraction)]

30 g of polyol [Acridic A801 (manufactured by DIC)] and 13.3 g of blocked isocyanate [Duranate TPA-B80X (manufactured by DIC)] 0.05 g of silicon-containing surface conditioner LHP-95 (manufactured by Kusunoki Chemical Co., Ltd.), BYK- 333 (manufactured by Kusunoki Chemical Co., Ltd.) was added, and 1.34 g of a 10% butyl acetate solution of the calcined product described in Production Example 1 was added to prepare a catalyst. The prepared liquid was applied to a polypropylene plate using a bar coater, and then the coated plate was dried for 30 minutes at a temperature of 130 ° C. The coated film applied on the polypropylene plate was peeled off and immersed in acetone at 20 ° C. for 24 hours. The results are shown in Table 1 (Tables 1-1 and 1-2) as Examples 1 to 12 and Comparative Examples 1 and 2.

A large value of the residual ratio indicates that the activity is higher, and those having a residual ratio of 65 or more are effective, and a residual ratio of 75 to 90 is preferable. Increasing the blending amount of bismuth trioctylate tends to increase the residual ratio (and corrosion resistance). When considering the experimental results, the amount of bismuth trioctylate can be considered to be 0.5 or more, preferably about 1 to 5 with respect to the fired product 1. As will be described later, when a mixture of bismuth trioctylate and ethylenediamine is used as an additional curing catalyst instead of bismuth trioctylate alone, the amount of bismuth trioctylate used can be reduced.

(Example of production of clear emulsion)

Epon 1004 (epoxy resin manufactured by Yuka Shell Co., Ltd.): 475 g is dissolved in 253 g of butyl cellosolve, 31 g of diethylamine is added dropwise at 90-100 ° C., and the epoxy resin having an amine value of 47 is maintained at 120 ° C. for 3 hours. The amine adduct was obtained. Next, 250 g of a polyamide resin having an amine value of 100 was dissolved in 107 g of methyl isobutyl ketone, and the mixture was dehydrated by refluxing at 140 to 150 ° C. to ketiminate the terminal amino group of the polyamide resin. After keeping at 150 ° C for 4 hours and confirming that no water was distilled off, the solution was cooled to 50 ° C, and then added to the epoxy-amine adduct. To obtain an epoxy-amino-polyamide-added resin varnish. To 9.4 g of a butyl cellosolve block of xylylene diisocyanate, 34 g of the above epoxy-amino-polyamide-added resin varnish and 4 g of 15% acetic acid were mixed, and 50 g of deionized water was added dropwise to obtain a cationic electrodeposition clear emulsion having a solid content of 33%. Was.
(Production of pigment dispersion resin)

Epotote YD-128 (epoxy equivalent 187, epoxy resin manufactured by Toto Kasei Co., Ltd.) 275 g, Eport YD-011 (epoxy equivalent 475, epoxy resin manufactured by Toto Kasei Co., trade name) 349 g, 342 g of propylene glycol monomethyl ether The mixture was charged, heated to 100 ° C., stirred for 1 hour, and cooled to 80 ° C. Next, 95 g of diethylaminopropylamine and 77 g of diethanolamine were charged, kept at 100 ° C. for 2 hours, and cooled to 70 ° C. The solid content of the obtained dispersion resin was 70%. This resin was neutralized with acetic acid so as to have a pH of 6.5 at the time of dispersing the pigment, followed by dispersion treatment.
(Adjustment of pigment paste)

  The pigment was dispersed in the composition shown in Table 1, pulverized and adjusted by a sand mill to obtain a pigment paste.

To 61 g of the cationic electrodeposition clear emulsion having a solid content of 33%, 12 g of the pigment paste of Examples 1 to 13 of Formulations 1 to 13 and Comparative Examples 1 to 2 of Formulations 14 to 15 shown in Table 2 was added with stirring, and deionized water was added. After dilution with 27 g, a cationic electrodeposition paint was obtained.
(Coating test)

A 0.8 × 150 × 70 mm cold-rolled dull steel plate treated with zinc phosphate was immersed in the electrodeposition paints obtained in Examples 1 to 13 and Comparative Examples 1 to 3 to perform electrodeposition coating. Electrodeposition was performed at a voltage of 280 V and a film thickness of about 20 μm, washed with water and baked. Baking was performed at 130 ° C. for 20 minutes in a gear oven. Table 2 (Table 2-1 and Table 2-2) shows the performance test results of the obtained baked coating film.
(Bath stability test)

The electrodeposited coatings obtained in Examples 1 to 13 and Comparative Examples 1 and 2 were filtered at 400C mesh after being aged at 30 ° C. for one month, and the amount remaining in the wire mesh was measured and evaluated according to the following criteria.
◎: less than 5mg △: 6-10mg
△: 11-80mg
×: 81 mg or more [Curability test 2]

The appearance of the coated surface when the coated surface of the electrodeposition coating film baked at 130 ° C. was reciprocated 20 times with gauze impregnated with methyl ethyl ketone was visually observed. The evaluation criteria are as follows.
〇: No scratch on the painted surface △: Scratched on the painted surface ×: The painted surface dissolves and the substrate is visible [Corrosion resistance test]

Cross-cut scratches were made with a knife until the base material was reached, and a salt spray test was performed for 1000 hours in accordance with JIS-Z-2731, and evaluation was made based on the rust and blister width of the knife-cut portion. The evaluation criteria are as follows.
◎: Rust and blister width is less than 1 mm from the knife-cut part〇: Rust and blister width are 1.1 to 2 mm from the knife-cut part
△: Rust and blister width 2.1 to 3 mm from knife cut
×: Rust and blister width 3.1 mm or more from knife-cut part [coating film smoothness test]

The appearance of the coating film was visually evaluated.
〇: good △: somewhat bad ×: bad

As described above, according to the embodiment of the present invention, even when the baking temperature or the curing temperature is lowered to about 130 ° C., a result excellent in coating film smoothness and excellent in rust prevention is obtained. I was able to.

Next, a case where a mixture of bismuth trioctylate and ethylenediamine is used as an additional curing catalyst will be described. MIK-1 and MIK-2 were made as additional mixtures (curing agents).
<Preparation of curing agent MIK-1>
50 g of BiCAT8210 [manufactured by Shepherd (bismuth trioctylate 28 wt% Bi)] was added to a 500 ml eggplant flask under a nitrogen gas atmosphere. Next, after stirring at an external temperature of 40 ° C. for 30 minutes, 90 g of N, N, N ′, N′-tetrakis (2-hydroxyethyl) ethylenediamine was gradually added. An exotherm was observed in the reaction system, and the color changed from yellow to orange. By reacting at an external temperature of 50 ° C. for 1 hour, 140 g of the title mixture was obtained. The bismuth concentration was a quantitative yield of 10 wt%.

<Preparation of curing agent MIK-2>
72 g of BiCAT8210 [manufactured by Shepherd (bismuth trioctylate 28 wt% Bi)] was added to a 500 ml eggplant flask under a nitrogen gas atmosphere. Next, after stirring at an external temperature of 40 ° C. for 30 minutes, 60 g of N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine was gradually added. An exotherm was observed in the reaction system, and the color changed from yellow to orange. After the generation of heat was stopped, 68 g of diethylene glycol monoethyl ether was added, and the mixture was reacted at an external temperature of 50 ° C. for 1 hour to obtain 200 g of the title mixture. The bismuth concentration was 10.2 wt% with a quantitative yield.
The compositions of Production Examples 14 and 15 were obtained using these curing agents MIK-1 and MIK-2.
(Production Example 14)

250 g of the 10% solid solution of Preparation Example 1 described above was added to 8.3 g of the mixture of MIK-1 and mixed, whereby 258.3 g of a 10% solution of the calcined product of Preparation Example 1 and MIK-1 at a weight ratio of 7.5 / 2.5 was added. Get. Subsequently, the solution was concentrated under reduced pressure and dried to obtain the composition of Production Example 14.

(Production Example 15)

By adding and mixing 510 g of the 10% solid solution of Preparation Example 1 described above to 17 g of the mixture of MIK-2, 527 g of a 10% solution of the calcined product of Preparation Example 1 and MIK-2 at a weight ratio of 7.5 / 2.5 was obtained. . Subsequently, the solution was concentrated under reduced pressure and dried to obtain the composition of Production Example 14.

  Table 3 shows the experimental results in the form to which each mixture of MIK-1 and MIK-2 was added. From the results, it can be seen that when each mixture of MIK-1 and MIK-2 was added, the amount of bismuth trioctylate used was significantly reduced in terms of the amount of bismuth as compared with the case of using bismuth trioctylate alone. This is considered to be due to the fact that MIK-1 and MIK-2 have improved stability and compatibility with hydrophilic solvents containing water, and inhibit the hydrolysis of bismuth trioctylate. By suppressing the hydrolysis, safety can be improved by avoiding release of octylic acid, and the amount of bismuth trioctylate used is reduced, which is advantageous in cost. Here, when examining the amount of bismuth in the gel fraction (residual ratio) of MIK-1 and MIK-2 as experimental results, the blending amount of bismuth trioctylate is preferably 0.05 or more, based on the calcined product 1. Is about 0.1 to 1. In this regard, it can be seen that when each mixture of MIK-1 and MIK-2 is added, the amount of bismuth trioctylate used is clearly reduced as compared with the case of using bismuth trioctylate alone.

  Therefore, by using the compositions of Production Examples 14 and 15 containing the respective mixtures of MIK-1 and MIK-2, under the same conditions as described above, including those using the composition of Production Example 2, The corrosion resistance and coating smoothness were examined. Table 4 shows the results. In each case, the corrosion resistance and the coating film smoothness were good, and the curability at a temperature of 130 ° C. was also confirmed.

Claims (18)

  It is a calcined product of a zinc compound and a bismuth compound, and the weight% Wz of zinc oxide and the weight% Wb of bismuth oxide or / and bismuth hydroxide have a relationship of Wz ≧ Wb, and furthermore, a rust inhibitor or / and / or A calcined composition, which is a curing catalyst.   It is a calcined product of a zinc compound, a bismuth compound and a silicon compound, and the weight% Wz of zinc oxide, the weight% Wb of bismuth oxide or / and bismuth hydroxide, and the weight% Ws of silicon oxide are Wz ≧ Wb, Ws ( Here, Wz ≧ Wb, Ws means Wz ≧ Wb and Wz ≧ Ws), and is a rust inhibitor and / or a curing catalyst.   It is a fired product of a zinc compound, a titanium compound and a silicon compound, and the weight% Wz of zinc oxide, the weight% Wt of titanium oxide and the weight% Ws of silicon oxide are Wz ≧ Wt, Ws (where Wz ≧ Wt, Ws means Wz ≧ Wt and Wz ≧ Ws), and is a rust inhibitor and / or a curing catalyst.  A composition having curing catalytic activity, characterized in that a fatty acid bismuth compound is additionally mixed with the fired product according to any one of claims 1 to 3. The composition of claim 4, wherein the fatty acid bismuth compound is bismuth trioctylate.  A composition having a catalytic activity for curing, characterized in that a mixture of bismuth trioctylate and ethylenediamine is added to the calcined product according to any one of claims 1 to 3.  The method for producing a fired product according to claim 1, wherein the firing is performed in a range of 300C to 1000C.  The method for producing a fired product according to claim 2, wherein the firing is performed in a range of 300C to 1000C.  The method for producing a fired product according to claim 3, wherein the firing is performed at a temperature in the range of 300C to 1000C.   In an electrodeposition paint containing a rust inhibitor or / and a curing catalyst in the paint composition, the rust inhibitor or / and the curing catalyst is a calcined product of a zinc compound and a bismuth compound, and the weight% An electrodeposition coating material characterized in that the weight% Wb of bismuth oxide and / or bismuth hydroxide has a relationship of Wz ≧ Wb.   The electrodeposition paint according to claim 10, wherein a fatty acid bismuth is added to the fired product.   The electrodeposition paint according to claim 10, wherein a mixture of bismuth trioctylate and ethylenediamine is additionally mixed with the fired product.   In an electrodeposition coating composition containing a rust inhibitor or / and a curing catalyst in the coating composition, the rust inhibitor or / and the curing catalyst is a calcined product of a zinc compound, a bismuth compound and a silicon compound, and the weight% of zinc oxide Wz, the weight% Wb of bismuth oxide or / and bismuth hydroxide, and the weight% Ws of silicon oxide are Wz ≧ Wb, Ws (where Wz ≧ Wb, Ws means Wz ≧ Wb and Wz ≧ Ws An electrodeposition paint characterized by having the following relationship:   14. The electrodeposition paint according to claim 13, wherein a fatty acid bismuth is additionally added to the fired product.   14. The electrodeposition paint according to claim 13, wherein a mixture of bismuth trioctylate and ethylenediamine is added to the fired product.   An electrodeposition paint containing a rust inhibitor or / and a curing catalyst in the coating composition, wherein the rust inhibitor or / and the curing catalyst is a calcined product of a zinc compound, a titanium compound, and a silicon compound, Weight% Wz, Weight% Wt of Titanium Oxide and Weight% Ws of Silicon Oxide Wz ≧ Wt, Ws (Wz ≧ Wt, Ws means Wz ≧ Wt and Wz ≧ Ws) An electrodeposition paint characterized by having:   17. The electrodeposition paint according to claim 16, wherein a fatty acid bismuth is additionally added to the fired product. 14. The electrodeposition paint according to claim 13, wherein a mixture of bismuth trioctylate and ethylenediamine is added to the fired product.