JPS60161467A - Electrically conductive electrodeposition coating material - Google Patents

Abstract

PURPOSE:The titled electrodeposition coating material, containing a nitride, carbide or boride of a ceramic having a specified specific resistance or below, having a very low variation in film thickness, and improved safety, nonpollution and economic efficiency, and suitable to highly electrically conductive films. CONSTITUTION:An electrodeposition coating material obtained by incorporating 100pts.wt. solid of a binder resin, e.g. a cationic or anionic resin, in an electrically conductive electrodeposition coating material, with preferably 50-400pts.wt. one or more of a nitride, e.g. TiN, carbide, e.g. NbC, and boride, e.g. WB, of a ceramic having <=10<-1>OMEGA.cm specific resistance and preferably <=5mu particle diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conductive electrodeposition coating material for obtaining a highly conductive coating film.

In recent years, with the advancement and development of cutting-edge technology, the input/output for printed circuits related to printed circuit boards, for capacitors, for adhesives, for electromagnetic shielding of electronic equipment, for antistatic purposes, and for 72 terminals of computer peripheral terminal equipment. For displays, digital clocks, cameras, electronic desktop calculators, automobiles, etc.
There is a growing tendency for conductive paints to be adopted in a wide range of industrial fields, such as displays for various instrument panels on Vλ boards for ships and aircraft.

Such conductive paints include conductive pigments such as car pump hooks, metal powders such as aluminum, silver, copper, zinc, and nickel, zinc oxide, and tin oxide. It consists of a conductive fiber selected from gold R oxides such as indium oxide, a binder resin, a solvent, a colorant, two additives, etc. 1. Usually applied by brushing, spraying or dipping. It is painted using a painting method such as , sink soaping, etc.

However, when the conductive paint used for the above-mentioned applications is applied using the above-mentioned coating method, the precision of the product
In other words, there are many problems such as variations in paint film properties due to variations in paint film thickness, safety issues such as fires and poisoning caused by solvents, and economics and low pollution issues such as solvent emissions into the atmosphere. It turns out that there is.

In view of these circumstances, the present inventors have conducted extensive research and found that &1
When electrodeposition coating is used as a coating method, the variation in film thickness is extremely small compared to spray coating, dipping coating, etc., and since water is used as a solvent, problems such as safety, pollution, and economic efficiency can be resolved. There was found.

The present inventors, based on the weak results, have developed the above-mentioned car pump hook and metal powder, which have been conventionally used as conductive fillers in conventional electromagnetic materials.

Continuing research by adding metal oxides and the like as conductive fillers solved the above problems, but it was found that the following new problems arose.

That is, when a carbon-based filler is used as a conductive filler, its large oil absorption causes problems under the p-type paper of the coating film.
It is not possible to add the amount necessary to obtain a highly conductive coating film on the order of days.

Furthermore, when metal powder is used as the conductive filler, the hardness is low, so pulverization becomes expensive, and stable high conductivity cannot be obtained.

In addition, due to the specific weight, W, sedimentation in the deposited paint is fast, etc. Stability % Workability, T! This causes problems in IN performance and economy.

Furthermore, when a metal oxide is used as the conductive filler, the highly conductive coating film targeted by the present invention cannot be obtained.

The present inventors continued their research to solve the above-mentioned problems and found that when one or more of Cefmix's nitrides, carbides, and borides were used as conductive fillers, such problems could be solved. I found out that it can be resolved.

That is, when such Cefmix is used as a conductive filler, its oil absorption amount is 1710% of that of a car pump hook.
Since the amount is small, it is possible to incorporate large amounts into paints,
Not only is it possible to obtain a highly conductive coating film, but also a dense, strong, and cheap coating film with good flow properties can be obtained.
It has high conductivity (paint film surface resistance of about 5 to 20 Ω/day) and high corrosion resistance, which was impossible with painting technology! The present invention was completed based on the discovery that M can be obtained during paint stability, sedimentation, etc. because it has a lower specific gravity, stability, and high hardness compared to metal powder. .

1 That is, the present invention provides a conductive electrodeposition coating material containing one or more of Cefmix nitrides, carbides, and borides having a specific resistance of 100α or less.

The present invention will be explained in detail below.

The conductive electrodeposition paint of the present invention contains, in addition to the above-mentioned CEFMIX as a conductive filler, a known binder resin commonly used in FIC paints, water, a small amount of an organic solvent, and if necessary colorants such as pigments and dyes. It contains agents, additives, other conductive fillers, etc., and is subjected to mts by uniformly mixing and dispersing them in a sigma mill, sand mill, burr mill, etc. in accordance with the conventional method of raw material manufacturing.

Cefmix nitride used in the present invention.

Compounds and borides are usually manufactured by hot pressing, pressureless sintering, reaction sintering, OVD, etc., and their specific resistance must be less than 10 Ω. If the resistance exceeds 100α, the highly conductive W1 film targeted by the present invention cannot be obtained, so it is not preferable.

Examples of nitrides in Cefmix include 1, for example, Tie.
, VN, NbN, ZrN, Tan, etc., and carbides include, for example, TiO, ffo, NbO,
Examples of the borides include ZrO, Tag, and 5iOWO@, and examples of borides include TiB2, ZrBz, and WB.

In the present invention, 1N or 2 of the Cefmix
The binder resin solid content in the conductive electrodeposition paint is N or more.
It is used in a ratio of 50 to 400 parts per 0 mN. The blending ratio of the Cefmix is the resin solid content of 1
If the amount is less than 50 parts to 00 parts, the coating film surface resistance value will be 104 Ω/mouth or more, and the highly conductive coating film targeted by the present invention cannot be obtained. This is undesirable because it becomes impossible to obtain a coating film without pinholes.

In addition, the particle size of the Cefmix used in the present invention is preferably 5μ or less, and if the particle size exceeds 5/1, sedimentation in the electrodeposition paint will be severe, resulting in poor stability and regional differences in film conductivity. Causes puffiness.

Undesirable.

As the binder resin used in the conductive electrodeposition paint of the present invention, tenionic or cationic binder resins used in ordinary electric wII paints can be used as they are.

When using an anionic binder resin.

It becomes an anionic type W coating, and when a cationic binder resin is used, it becomes a cationic electrodeposition coating.

Such anionic binder resin is a polycarboxylic acid resin with a backbone of drying oil, polyester, polybutadiene, epoxy ester, polyacrylic ester, etc., and is usually an organic amine.

Alternatively, it is neutralized and water-solubilized (water-dispersed) with a base such as Sumo wrestler Ikari, and is negatively charged.

Therefore, when applying electricity to the object to be coated, by applying one current to the anode, the surface of the anode (object to be coated) IC1I! An i film is formed. Cationic binder resins are mainly polyamino resins with skeletons such as epoxy resins and acrylic resins.1 They are usually neutralized and water-solubilized (water-dispersed) with an organic acid such as acetic acid.
and is positively charged.

Therefore, when coating with W, the object to be coated is the cathode, and a coating film is formed on the surface of the cathode (the object to be coated) by one current application.

As the electrodeposition coating conditions of the present invention, commonly known conditions can be applied to either anionic or cationic electrodeposition coating.

The present invention will be explained below with reference to Examples.

Example 1 ■Epoxy V-based cationic binder resin 27MIk part (1131 in the Shinto Toyo Co., Ltd. trade name: non-volatile content 75%) ■Titanium nitride (specific resistance 22-130μΩα, 80# particle size 1.3μ) ■Minetsurutarpen (carbonized) Hydrogenated solvent) 6〃■Diacetone γ Luco A/(Ketone・10〃Alcoholic solvent) ■Deionized water 544 # First, ■~■ were dispersed in a Par/I/Mill for 2 hours to a particle size of 5μ or less. 0 Next, gradually add ■ while stirring, and conductivity of the present invention with a non-volatile content of 15% and a pH of 5! There was a dispute on the floor. Electrodeposition bonding was performed using the obtained electrodeposition paint, using a zinc phosphate treated plate as the object to be coated as a cathode, under conditions of a material temperature of 28±1°C, a voltage of 120V, and a current application time of 5 minutes. .

The performance of the resulting coating film was as shown in Table 1.

Example 2 ■Polybutadiene-based anionic binder resin 26 parts by weight (Shinto Toyo Co., Ltd. trade name 5-90: non-volatile content 78%)■
Expanded titanium (specific resistance 77~173μΩ) particle size 1.1μ
) 80 〃 ■ Butyl cellosolve 3 # ■ Ethyl cellosolve PP 10 # ■ Deionized water 21〃 ■ Deionized water 527〃 tf ■ ~ ■ were dispersed in a pearl mill for 2 hours to a diameter of 5 μ or less 9 Then, with stirring ■ was gradually added dropwise until the non-volatile content was 15
%, a conductive electrodeposition paint of the present invention having a pH of 7.5 was obtained.

Electrodeposition coating was carried out in the same manner as in Example 1 using the obtained electrodeposition paint.

Example 3 Instead of titanium nitride, specific resistance 2 to 5 μΩ 1° particle size 1.5
A coating material having conductivity 1 of the present invention was obtained in the same manner as in Example 1 except that μ titanium boride was used.

Electrodeposition painting was performed.

The performance of the resulting coating film was as shown in Table 1.

Comparative Example 1 Electrodeposition coating was carried out in the same manner as in Example 1, except that 3.5 parts by weight of a conductive car pump hook was used instead of 80 parts by weight of titanium nitride.

The performance of the resulting coating film was as shown in Table 1.

Comparative Example 2 An electrodeposition paint was prepared in the same manner as in Example 2 except that 80 parts by weight of nickel powder was used instead of 80 parts by weight of titanium carbide. Electrodeposition coating was carried out in the same manner as in Example 2.

The performance of the resulting coating film was as shown in Table 1.

Comparative Example 3 An electrodeposition paint M was prepared in the same manner as in Example 5, except that 80 parts by weight of zinc oxide was used instead of 80 parts by weight of titanium boride, and an electrodeposition coating test was carried out in the same manner as in Example 5. Ta.

The performance of the resulting coating film was as shown in Table 1.

Claims (1)

[Claims] Cefmix nitrides and expanded products with a specific resistance of 100 or less,
A conductive electrodeposition paint characterized by containing one or more borides.