WO1983000511A1 - Electrode for use in cationic electrodeposition coating and coating method using the same - Google Patents

Abstract

An electrode for use in cationic electrodeposition coating comprising a sintered metal oxide having electroconductivity such as ferrite or magnetite, and a method for cationic electrodeposition coating using said electrode as an anode.

Description

 Fine

Title of invention

 Cathode-type electrode for electrodeposition coating and electrode ': coating method

Technical field

 The present invention relates to an electrode made of a metal oxide sintered body for use in cation-type electrodeposition coating and an electrodeposition coating method using the electrode.

Background technique ^

 In recent years, the importance of improving the protection of automobiles from the point of view of paint has been emphasized. In order to prevent casting, materials and chemical conversion treatments. Type of paint, coating method, resin structure, etc. Are being studied from many angles. Among them, electrodeposition coating is the most effective and economical method for protecting the inner surface of the bag structure of complicated structures and difficult-to-coat spray paint, such as automobile bodies. This method is widely used at present.

In the conventional electrodeposition coating method, the varnished electrodeposition method is used because the paint used is inexpensive, the sintering degree of the coating is relatively low, and the equipment cost is relatively low. The main use was paint. However, in the anion-a electrodeposition coating method, there is no elution of an electrode (candle) made of iron or the like soaked in paint or immersed in paint. However, the elution at the time of electrodeposition coating in order to make 袪 ¾ j 陽 箜 箜However, since the surface of the artificial skin is reduced and the thickness of the coating formed on the surface of the substrate is thin, the environmental fluctuates. As a result, conventional Anion electrodeposition coatings have not been able to provide sufficient protection. For this reason, recently, cationic electrodeposition coating has been widely adopted.

In order to perform cation-type electrodeposition coating, it is necessary to use water-insoluble street fats, such as bisphenol-type epoxy and ^ -gloss glycidyl groups. a Mi comma other water-insoluble volume Li a Mi emissions Street R becomes by ring opening by adding a second a Mi emissions - the NH _2, Remind as the following reaction formula (I), vinegar ¾中 和 Neutralize organic drums and the like as ¾ (water-solubilizing agent) AH to make aqueous resin R-NH ₃ ÷.

 R-XH + AH → H- Hg + + A- (I)

 The above-mentioned aqueous resin and, if necessary, are used as a negative electrode (hereinafter referred to as a cathode) in a cation-type electrodeposition paint solution containing a crosslinking agent and a pigment. * Separate and separate from this: C Soak X in the molten raft, for example, a positive electrode (hereinafter referred to as “stainless”, carne, etc.), with these (铵 painting). Yang 'and-

As a result of this O energization, the coating component that has been positively electric-powered 中 fc 中 中 中 容 中 容 容 容 容 容 容 容 容 容 容 容 容 容 筏.袠 袠 · 行 行 行 行 行 行 行 Form insoluble coating si O ₀

 2 H. 0 ÷ 2 e-→ H. + 2 0Η ~

 (ID

Ori "-\ H _S ⁺ → R-: \ H. ₂ + H., O

Well, i #;!: Well, as shown in Equation 1; For example, in the case of stainless steel, along with the elution of metal ions, the occurrence of a bitumin can be seen as shown by the formula] y.

M → ^{n +} + ne-(I)

40H-1 → 0 ₂ † + 2H ₂ 0 + 4 e- When the anode is made of carbon, the elution reaction represented by Formula M does not occur because it is not metal, but the reaction of Formula IV As a result, carbon itself is converted into a carbon. Therefore, the sun is blinking over time. In addition to cutting damage, especially in the case of metal, these metals are mixed into the eluted metal ion solution and coagulate and deposit on the paint, and these metal ions are deposited on the substrate. On is also agglomerated, and the resulting coating film has a poor protective property, and the coated surface is rough.] In the case of bonbon, the fine powder of carbon is dropped off by oxidation, etc., and this powder mixes during melting, and the electrodeposition coating can be read in this condition. However, there was a problem that the surface of the painted material was soaked that the appearance of the painted surface and the protective property deteriorated.

 It is difficult to dissolve. 碭 Use high-grade stainless steel such as SUS310 as the material. Use of a noble metal such as platinum is conceivable, but the stainless steel: i Thus, there is a problem that some elution cannot be avoided and that noble metals are too high in practical use. Furthermore, carbon and black also have the problem of poor processability.

Ming disclosure

The present invention has been made to solve the above-mentioned conventional problems, and has low elution and no elution. The purpose of this material is to use the metal beating that it has, and the anode material is made of a metal beating that has poor formability and workability. The purpose is to show the concrete structure of the system.

 In addition, according to the present invention, the cation-type electrodeposition coating method includes providing a coating material in a coating solution and an opposing counterpart between the coating material and the counter electrode. A method of forming a cation electrodeposition coating on the surface of an object by applying a direct current voltage. ' It is a recommendation to use it.

The present invention: Te-electrode, that is, a metal oxide used as an electrode ^: is a conductive material, and is known as a magnetite to eliminate F eO—Fe ₂ 0 magnetic iron oxide represented by _3, and at full E La wells and睜barrel · NFE ₂ 0 ₃ is ¾ ¾ metal ¾ of the I table. Here,: νί represents a divalent metal ion, such as:, ίη, Xi, Cu,, Co, and Zn.

The metal bowed in the present invention: i: It is necessary to have conductivity for the purpose of use. In the case of the magnetite: the resistivity is low and it does not matter-but the ferrite is used; Some have various rates depending on the situation. Funilite: One-way ferromagnetism, various transformers such as TV, radio, audio equipment, communication equipment, permanent stone, f≡ «child,? Sakai: It is used in the electronics industry as a device, etc., but its ^ il S is as large as 100 Ω · cm to 100: Viil 'cm. Therefore, if the resistance 军 of the ferrite is also large, the current is low. Below, fever, etc., may be severed; The ferrite used as the electrode material of the kishi needs to have a low resistivity. Ferrite is used to obtain low resistivity mainly because of the conduction of electrons due to hopping of electrons between Fe ^{2 +} and Fe ^{3 +} . is, ^ formed in full E La wells: F e ₂ 0 ₃ there is no Do et al. if Re, such excess only. The cations of the present invention (metal drums used as the coating-type coating material 1) have a volume specific electric resistance value of 20 TC according to AST-Μ · D257-011. , Oite to load voltage 2 0 V, is rather than the preferred 1 0 ⁵ Ω · α? ζ below 1 0 ³

Ω · ^ or less, more preferably 0.3 £ 2 * or less. Specifically, a recommended composition of iron oxide and a metal oxide other than iron oxide (such as ΐΟ, ηΟ, CoO, gO, CuO, Ζηϋ, CdO, etc.) Chi Tsuzumika iron (Fe ₂ 0 ₃₎ and the total amount of:? to pair Te '5-4 0 molar, preferred to rather than the 2 0-4 0 molar ^, good] preferred to rather is of 4 0 molar It is a metal oxide sintered body having a spinel crystal structure made of a metal oxide.鉄 In the case of iron oxide, the composition ratio is preferably Fe03 0 to 5 α-Fe ₂ 0 ₃ 5 3 to 7. More preferably, FeO S 5 to 45—Fe ₂ O ₃ ό 5 to 55% ぁ i, and more preferably a tool ^ 4 4. C 'FeO— 53.5% Fe ₂ O _{3 - 1. 0 9¾ S i 0 2} - 0.9 ^ a 1 2 0 3 - C.5 C a 0 - 0.1 ^ MgO by | that Ki de 3 of that and this Ru opened a sintered body 'is. 0. Te _{S ί 0 2 4~ ό, C} a 0, MgO your good beauty A 1 ₂ 0 ₃ each ";! ¾ ¾ ¾ Katama鼋If F e 0 of, F e ₂ 0 ₃ of '! ~ 1 may be included. The magnetic iron oxide, of as a power ¾ of the full E La wells ^ property, vinegar Te down Les vinegar has been used as a conventional Hihitsugi (S US SO ^4, the same 31 0, 31 7) Ya Carbon, for example, Graphite! ) Good, especially ferrite, with little elution and good.

 Metal-made electrodes are already known, and their production methods are also known to the public (for example, Japanese Patent Publication No. 52-SCM51 and Japanese Patent Publication No. S51-55394). Therefore, the electromagnet of the present invention can be manufactured from the above-mentioned magnetic iron hydroxide or ferrite according to a known method.

When showing an example of the manufacturing method, Eba ^{_{£ 1 6 2 0 3 9 5~0}} 2 molar

,: I, C ο, Aig, Cu, ηη or Cd) and at least one of 5 to 40 moles is combined, for example, when fully combined in ball mill After heating, the mixture is heated in air at 8α0-1000 for 1-S hours, cooled, and ground to obtain a fine powder. The powder obtained by pressing the powder or the water obtained by adding the powdered water ⁷ ;! mETHOD ask the example extrusion City molded to free volume 5 volume or less of an inert gas shaping ^ Wotsu rather] ?, this adult ¾ a o · ₂ gas having a desired shape ^ by One in the and this if, New ₂ gas or picture you in the cut园気of C0 ₂ gas - Te 1 3 00-1 4 30 5 to 5 ^ between the pressurized ripe and in匸^ tighten not binding, 0 ₂ gas content Ο small non-r § a gas even if 'X ₂ get in gas Introduction COo in gas more than people in the to power ¾ and in Tsu good and this for cooling purposes. OMPI One IPO The electrode obtained in this manner has a relatively high strength and exhibits a resistivity in the above range.

As a starting material in the above-mentioned F e ₂ 0 ₃ your good beauty but (λί is the same and) was used, Fe ₂ 0 to ₃ of the die translated into Fe ₂ 0 ₃ 9 5~ 6 0 mode Fe in the amount Do not Let 's that Do Le, FeO your good beauty; P e ₂ 0 ₃ 1 kind or is of but it may also be a mixture of 2 ¾ or more. Also acid like MO! Instead of the product, a compound that can be converted to an oxide by ripening, for example, a carbonate, a oxalate, or the like can be used.

Although the case of Ma Gune Thailand gate electrode Ru obtained in the same manner as described above, pure F e ₃ 0 ₄ and if fees if ^ example, port re bi - Le A Le co - Bas Le Lee emissions da one and Professor leading frame as a, molded, that Ki out and this may be one good and the child to solid ¾ sintered in C0 ₂ atmosphere at 1200 to 1300.

The electrode of the present invention can be used in the form of a plate, a prism, or a round bar of the above-mentioned metal oxide bonded unit. However, if the surface area is increased, Metallization that may occur when current is applied ¾7 'A single body of the surrounding body ^ Avoids non-uniform current distribution from the electrode due to its own volume-specific electrical resistance In order to prevent damage due to mechanical shock, etc., the metal oxide is formed into a closed body, and the body is made into a boasted body. Solder or conductive substance (eg, epoxy resin containing sS or graphite: Trade name Dotait Kuraka ^)) Aluminum core, iron core, stainless steel It is good to adopt a metal part village such as a slab core or a collar, especially a stainless steel IS material.

 In the above configuration, when stainless steel is used as the core material, the temperature rise at the time of a large current and the unevenness of the current distribution are eliminated, and the burnout is lost by 5 times. Even so, the elution of metal ions is small due to the characteristics of the stainless chain.

 In electrodeposition coating, when the object to be coated is large, such as a car body, and its structure is complicated, but it must be ensured that the coating can reach the inside of the box 十分 sufficiently. In addition, the electrodeposition sand itself must be large and the electrodes used must be large, and it is sufficient to install the electrode only on the side of the electrodeposition tank. If the strength and film thickness cannot be obtained, electrodes must also be provided on the bottom of the electrodeposition tank.

 In order to solve the above problem, it is difficult to make a large cylindrical body by sintering in order to enlarge the electrode, so a cylindrical body with one end closed and a cylindrical body with both ends open It is preferable that the core material is inserted into the cylindrical body using the rod metal part as a core material, and the core material is bonded and fixed via a conductive material. The joints between the cylindrical parts are straddled to form a hardened resin that is proud of the two, and the hardened resin is filled with the solid body in the space between them. It is good to make it better.

In addition, as the electrode to be provided at the bottom of the electrodeposition sheath, a 覆 5 cover lead is joined to the ferrite electrode, and the junction is joined with ^. A cylindrical hard resin body that covers a part of the cylindrical body of the sintered body on the outer periphery of the electrode and a part of the lead wire is fitted to the electrode, and the hard resin body of the lead 檨 portion is fitted. Then, a hardening resin is filled and hardened, and if necessary, an annular or cap-shaped hard resin body is screwed to both ends of the hard resin body. With this configuration, the electrodeposition liquid does not damage the lead and the electrode core material even in the electrodeposition tank, and can be easily installed at any position in the tank. You.

 As described above, the present invention can increase the surface area of the electrode obtained by using a metal oxide ¾J sintered body as a cylindrical body. In addition, since a core material such as stainless steel is inserted into the cylindrical body, it has the advantage that it is strong even if it is strong. In the case of an electrode consisting of a metal hesitate or a simple substance, when a large current is applied, a temperature rise occurs in the electrode part, and the resistance of the coating liquid is sintered. In some cases, current distribution from the electrodes became non-uniform due to electric resistance. However, in the present invention, such a disadvantage does not occur because a metal member is inserted. Further, according to the joint structure of the present invention, there are advantages that a large electrode can be freely formed.

Still further, according to the electrode having the lead structure of the present invention, the electrode having the lead wire to be abutted, and the outside that comes into contact with the liquid is made of a metal oxide bond ^ Electrodeposited because the connection between and has been made. ! The number can be easily set in the * position as appropriate (note that it is possible to mark ft. Even with large parts like, it is possible to obtain good paintability and the desired film thickness.

BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a cross-sectional view showing an example of an apparatus for performing a cation-type electrodeposition coating method.

 Fig. 2 shows an example of another apparatus for carrying out the cation-type electrodeposition coating method.

 Fig. 5 is a vertical new view of another apparatus for carrying out the cation-type electrodeposition coating method.

 FIG. 4 is a vertical new view showing an example of the electrode of the present invention using a metal part ^ as a core material,

 Fig. 5 is a horizontal new view of the electrode of Fig. 4,

 FIGS. 5 and 6 are cross-sectional views showing an example of the electrode of the present invention consisting only of a metal-assisted metal complex.

 FIG. 8 is a new front view showing an example of the electrode of the present invention of S in which metal oxide sintered ^ is read;

 FIG. 9 is a sectional view of a main part of the electrode of FIG. 8,

FIG. 10 is a front view showing ¹ of the electrodes to which the lead wires are connected,

 Fig. 11 is a new view of the main parts of the power supply shown in Fig. 10;

 FIGS. m 12 and 15 are new views showing the usage of the electrode shown in FIG. 10.

The best form to carry out the invention

 Hereinafter, the present invention will be described based on Examples and Comparative Examples. In each case, the body solid electrical resistance; straight, A S Τλί D 2 5 7- 6 1

O PI Thus, it can be obtained by setting at 20 and 20 V. Example 1,

(A) Preparation of anode plate

Using magnetic iron oxide and ferrites A to D with different ^ product specific electrical resistance values, an anode plate with a length of 100, a width of 50 丽 and a thickness of 4 was manufactured by a sintering method. . Each obtained sintered body volume resistivity of (positive ¾ plate) shown in the ^first one ² tables.

 Table 11

 Ginari

Component Fe ₂ 0 _3: \ i 0

Mol ^ ¹ mol mol ferrite A • 5 δ ^¾ G 17

II B 53 57 1 0

II C 55 45 0

11 D ό 0 40 0

〇 process is more than 1 ¾ of F e ₂ 0 ₃ and N i 0, MnO were mixed at a ratio of the first _ Table 1, for example ball - were thoroughly mixed in a non-mil, 8 00 ~ in the air 100: Heat for 1 to 3 hours, cool, and pulverize to obtain a powder. This butterfly powder in the slip ¾ obtained by the addition of water ^ out Shi in Tsu by the and the child to be formed desired shape ^ of molding ^ the work, this Arukatachi: 0 ₂ content of 2 ^ amount of gas the following:. ^ gas cut S to have in the gas' formation temperature 1 5 00~ 1 4 3 ~ 5 ^ ¾ IJZ to at 0 0 TC tighten to癍结, then 0 ₂ gas content of not less \ ₂ Slowly cool in gas to obtain an electrical resistance of SK. ① Preparation of paint

 Ethoxy-polyamino fingers with a resin base number of 80 are treated with acetic acid.]? Neutralize with a neutralization equivalent of 0.5, and ethylene glycol monoethylen To a varnish dissolved in deionized water containing teraacetate, 3 parts of carbon black, 100 parts of solids of the varnish, and 3 parts of carbon black The lacquers were combined and dispersed in mill for 20 hours to produce a cation-type electrodeposition paint. Obtained paint ': The deionized water was further added to produce a solid content of 12%.

② Painting method

As shown in Fig. 1, a container with a length of 40 Q, 11 C and a depth of 150 is placed inside a plate tank 1 with a vinyl chloride resin resin lining 2. In the middle, the paint solvent 5 prepared as above is bathed. Next, the baking book (结 丫 S) ⁴ prepared in the above (a) is attached so that the part from above to the lower side of 1D ™ comes out on the surface of the bath C]. , ¾ ¾ 理 ¾ ¾ 1 (150 X 50 X 0.8 T! H SPC cold rolled sheet with Bond Light # 150 from Japan Power Rising Co., Ltd. Nii)

Immerse 5 in the bath. The two counter electrodes 4, 4 are arranged so as to be symmetrical with respect to the paint J5, and the paint is uniformly applied to the paint 5; These counter electrodes ⁴ and 4 are connected by a lead, and the coating 5 is connected to the lead.

Ο Η_ It is electrically connected to the power source 7 via the contact 8.

 If power is supplied under the following conditions in this state,

 ¾ 4.4 is positively charged and positive] ?, Coating material 5 is negative] ?, and the power-type paint is deposited on the surface of the coating material 5.

 til.

 <Electrodeposition conditions>

 • Bath temperature 30 TC

 • Distance between fences "1 5 D

 • Anode area 5 cm

 • Cathode area / c

 • DC voltage and 1 ό 0 V

 '' 3 minutes when energized

After the electrodeposition coating, 2 0匸of the tap water with can spray ^{for one} minute at pressures 0. ⁵ / c and water ^, then ¹ 8 0 _X:? ³ was and cured with 0 minutes baked in. Various materials: Teyo]? Using the manufactured anode plate, the electrodeposition coating was performed in the same manner, and the initial current value and the thickness of each electrodeposition were measured. The results are shown in Table 1-2.

Comparison li 1

 Carbon (black), Tokai Carbon, trade name “G52J:” and stainless steel SUS316 are used as counter electrode materials. Electrodeposition was performed in the same manner as in Example 1 (mouth) .Electrodeposition using the respective anode purifier ^-"Initial electrode ^ and film thickness were measured. The results are shown in Tables 1-2.

OMPI

WIPO, ^ y Table 12

r

Jp

30 V

 Early period

 Value 11 1.9 1.c 1.9 (A) 2Ό 1.8 1.8 21 10 19 20 20 20 20

(β)

00 V

 Early period

2.2 1.3 2.0 2.1 22 2.2 2.2 Volume specific electricity 1Χ10- ¹

2X10 ⁵ 1X10 ³ 90 0.3

Resistance directly.cm)

Example 2

(A) Preparation of anode plate

 In the same manner as in Example 1n, ^ plates of magnetic iron oxide and ferrite D were prepared. Corrosion resistance test method

 A 5: 1 solution of vinegar diluted with deionized water and a 5% solution of milk in deionized water were mixed at a ratio of 1: 1, and the same ^ II linen as in Example 1 (mouth) was mixed. And put each anode plate manufactured in step f) above so that the portion from the top to the bottom of the 10 dishes from the top of the dish rises above the liquid level of the bath, and then the SPC ^ The ^ fe plate was used as a cathode under the following conditions, and the corrosion resistance was determined by the weight and weight of each lever. Table 2-1 shows the amount of elution from each positive plate.

OMPI Electrolysis conditions>

 'Liquid temperature: 30 3

 '' Distance between poles: 1 5 0

 • Anode and cathode area

 : 7 Dcm

 • DC current: 5 A dm2 and 0.01 A / dm2 alternate every hour.

 • Period: 100-; I00 hours

 Comparative Example 2

 Using the carbon and stainless steel SUS310 used in Comparative Example 1 as the fying surface, a food-eating test was conducted in the same manner as in Example 2 (mouth). The elution amount of each plate is shown in Table 2-1. Table 2-1 Amount of cathode material dissolved (years) Competitiveness Iron oxide 50 ferrite D 0.5 stainless steel SUS S10 1 G, 000 Carbon (graphite) 1,000 Same test as above Nickel ferrite

(Fe ₂ 0 ₃ - isiO) each conductive when the molar of NiO was 5-4 5 molar change in electrode ^ elution amount and ¾ anti value loss: "and constant. The results are shown in Table 2-2. -1 ό

 The electrode was manufactured in the same manner as in Example 1.

2 — ^

NiO * C mole,

Resistance value Cn-cm Ferrite D 4 C 0.5 0.δ

 Ni ferrite I δ 0 1.0.0 0.07

 a E 2 0 2.0 0.03

 I 1 0 4.5 0. 0 2 a IV 5 7. 0 0. 0 1

It V 2 1 2.0 0. 0 0 5

If I 4 3 0.5 0.50

 Ferrite C A 5 0.1 Lower 9 0.0

The above table shows that NiO 5 to 40 mol is better. Implementation ^ i 5

In an actual electrodeposition line, as shown in Fig. 2, a lining 2 made of vinyl chloride or the like is applied to the inner surface of a plate tank 1. The coating solution s is bathed in the container. This coating had almost the same composition as that described in Example 1 (°). The anodes ¾ 4, 4 ′ and the coating 5 are immersed in the coating liquid S, and the anode plates 4, 4 ′ are 籙 6 at the lead 電 6 and the direct current: 17 O positive ^ In addition, the workpiece 5 is connected to the (force source) side via a contact 8. In the present embodiment, the solar cell is used in combination with the one having the same structure as that shown in FIG. 1 and the one having the S-film structure. That is, a diaphragm box 9 is formed around g of ¾ ¾ ¾ 4 ′. An ion exchange resin film ¹⁰ is provided on the surface between the positive ⁴ ′ of the diaphragm box ⁹ and the object 5 to be coated, and the inside of the box 9 is provided. The membrane water is filled with 12. By forming the anode into a diaphragm electrode structure as described above, even if the material elutes slightly from the anode, the eluted material is not mixed into the coating liquid and the quality of the coating film is improved. Is improved.

 FIG. 3 shows the arrangement of the anode in the longitudinal direction of the electrodeposition tank, 4 indicates the positive electrode having the bare electrode structure, and ^ indicates the anode having the diaphragm structure.

The electrodeposition coating method was performed under the same operation and conditions as described in Jeongseon example 1 (mouth). Also, in an anode plate forming material used in this real旌例, vinegar Te down Les scan? (SUS 5 ¹ 0), mosquitoes over Bonn (grayed La incompatibility g) your good beauty off E La Lee O using D

 Electrodeposition coating was performed on each anode forming material for about one year, and the weight of each anode plate was determined. Table 5 shows the results. As evident, the weight was the least when ferrite was used. The electrocoating property was not a problem in the case of ferrite, but in the case of stainless steel, an increase in Fe ion was observed in the paint. Was terrible. In the case of the carbon, a part of the carbon powder was dropped off, and the penetration of the abduct in the coating liquid was confirmed, and the appearance of the coating film was missing.

Ο Ρί Positive electrode material thickness

 Ferrite 0.1 or less

 Carbon 1.0

 Stainless steel (SUS510) 5.0

As is clear from the above description, the electrodeposition coating method of the Jing Jing example uses a metal oxide sintered body with excellent conductivity for the plate, and thus the There is almost no elution at the time, and there is no possibility that impurity ions are mixed in the solution. At the time of electrodeposition; Since it is not oxidized by oxygen generated in the immediate vicinity, there is no possibility of deterioration of the electrode due to aging and partial desorption. Therefore, an impure fine particle is not mixed into the coating solution, and an excellent skin coating film having no coating defects can be obtained. At the same time, since there is no deterioration of the electrode, the ft durability of the electrode is improved, replacement work is eliminated, and there is a great advantage in terms of cost and labor 0

 ^ Describes the specific structure of the electrode of the present invention ^. Jeongjeong 4

FIGS. ^{4 and} 5 show the ¾ ^ of this kiyoshi, 11 a is a rod-shaped stainless steel ::, and has a terminal 12 on the upper side, and a shaft has ! It is covered with a face-shaped hollow wiping metal oxide / compound 4a which is closed via conductive materials such as &, solder, and conductive adhesive. According to this electrode -1? -Since the metal oxide sintered body 4a is electrically connected to the stainless steel 11a via the conductive material 13 on the entire inner wall surface, the temperature rise and current during a large current non-uniformity of the distribution of such ku Do Ri, or even any chance sintered body 4 a is to etc. corruption exposed nest Te down Les scan steel ^{1 1} a, it Ri by the characteristics of the scan Te down Les scan ho No metal ions are eluted.

 As a metal oxide sintered body having this configuration, an electrode using ferrite (hereinafter referred to as a ferrite electrode) is used in a force-thione electrodeposition coating method. To do this, for example, as shown in FIG. 1 or FIG. 2, it may be performed in the same manner as in Examples 1 to S.

In the above-mentioned electrodeposition coating method, a DC top voltage of 25! (Trade name, manufactured by Nippon Paint Co., Ltd.) was used as the paint. ] 280 Y is applied, the length of each electrode is about 1800 mm, and the object to be coated 5 is a tin plate automobile body of about 5 QW ² for about 15 months per month. After about one year of electrodeposition coating with the 9000 unit, both the ferrite electrode used naked and the ferrite electrode in the diaphragm box 9 were removed. eyes down Ri is rather very small in, and 2 8 is one der degree about 2 ^7. to 5 dew ing in diameter, it was possible to sufficiently ^ Nyo use was or. In addition, the current from the electrode also flowed uniformly over the entire ferrite surface, was extremely good, and the electrode itself generated little heat, so there was no particular problem.

For reference, the same electrodeposition coating as in Example 4 above was performed using the ^ electrode, and the following results were obtained. Was o

1) full E La wells collector fitted with a terminal ¹ 2 and through the conductive material ^{1 4} to the upper end of the cylindrical metal oxide sintered body ⁴ 1 consisting Ri by full E La wells that shown in ό Figure ^ a used to generate heat electrodeposition coating line of Tsutato this filter, in the sintered body ⁴ 1 and趕子1 second connecting portion. and Ri Do different current distribution at the terminal side and the previous遌側of the sintered body 4 1 The current was small at the tip. About one year later, the decrease in outer diameter was slightly greater on the terminal side, and the diameter was about 2ό in 28 suspensions.

2) full E La wells electrodes attached preparative terminal ¹ 2 di tio Lee emission sheet 1 5 on a plate-shaped full E La Lee Bok by Ri made the upper end of the metal oxide sintered body ⁴ 2 shown in FIG. 7 When electrodeposition coating was performed, heat was also generated at the connection between the sintered body 42 and the element 12, and the current distribution was different on the tip side from the element ^ of the sintered body 42. There was little current in the part. About one year later, the decrease in wall thickness was slightly greater on the terminal side, and the thickness 5 was about 4 plates.

3) As a positive electrode, the same electrodeposition coating was performed by mixing stainless steel ^ S US510 with the ferrite electricity of the present invention shown in FIG. ⁴ above. The current flowed uniformly, and the electrode itself generated little heat. However, after about one year, the outer diameter was reduced by 1όι ^, which was extremely large at 5 dew in diameter. Some were cut off.

 ) When the same electrodeposition coating was performed using SUS 516 as the anode for all electrodes, the same as in Example 5) above

C 'i The coating has a large amount of iron ions in the paint, causing some of the paint to coagulate, and the appearance of the resulting coating film to be rough, such as unevenness, and has an anti-mirror property. Was getting worse.

 5) Using the positive effect, iron SS 41 was mixed with the ferrite cell of the present invention shown in Fig. 4 above, and the same electrodeposition coating was performed. Elution loss occurred within a few days.

6) As the sun, when the forehead and aluminum were mixed with the ferrite cell of the present invention shown in Fig. ⁴ above; g, the same electrodeposition coating was performed. The aluminum orange lost elution in a few days

 As described above, according to the ferrite ¾S shown in FIGS. 4 to 5, the conductive material and the metal are provided around the periphery of the stainless steel ^. Since the oxide sintered body is sequentially covered, even when a large current is applied, the temperature does not rise and the current distribution is uniform.

 In addition, since stainless steel is used as the metal member, even if the metal sinter is sintered and cracked due to an external impact, etc., Due to the nature of stainless steel, ^ is less eluted, and ^ ions and aluminum ions are eluted and mixed in paint as in the case of copper and aluminum. Incorporation rarely causes roughening of the coating film or deterioration of the mirror protection. ,

Real 53 5

This ^ represents the ^^ of a denki which is a combination of a cylinder made of a metal drum and a sintered body. f OMPI ― FIG. 8 shows the whole of the electrode of this example, and FIG. 9 shows the main part thereof.

 1 1 is a rod-shaped metal member such as copper, iron, stainless steel, etc. Through a conductive material 13 such as &, solder, conductive adhesive, etc., a metal oxide sintered body with a closed U-shaped hollow cylindrical body i with one end closed ^ 4 a and both ends The metal oxide sintered body 4b as an open hollow cylindrical body is fitted and covered. Further, connecting portions 1 ό made of a grease covering structure are provided at opposing portions of the upper and lower connectors 4 a, 4 b.

First, a cylindrical hard resin body 17 made of a fluororesin (for example, trade name Teflon), a polychlorinated valve, nylon, or the like is connected to each of the above connecting portions ^{1 、} by the above-described firing method. body 4 a, 4 b facing in the Let 's that straddle the outer periphery of the portion of is莰合, Te off this tree Aburatai ¹ 7 step portion 1 7 a provided on the inner surface sides of, 1 7 a b down, skin, insert the rubber of which ◦ Li in g ¹ 8, simultaneously with the Se' the outer periphery of the gold Chen ¾ of ¾ sintering ^ ⁴ a, 4 b, Mesune provided on both the ί green di Parts 17b and 17b also have a hollow cap made of Teflon, polyvinyl chloride, etc., and have male screws "I9a, 19a" around their circumference. When the body was established

¹ , ^{1 and 9} are shown. Ri by the this hard 'fat ^ 1 9, 1 9 ϋ wear of,. 0 Li in g 1 8 ... is pressed Ri by the beyond, the exterior of the hard銜脂侔¹ 7 and each ^^ body 4 a, 4 Make close contact with b without gap. Next, after fabricating the structure ^: in this way, a two-dimensional curing type, such as a two-component curing type A curable liquid resin such as epoxy resin, polyester resin, polyvinyl chloride, polyvinyl chloride, etc. is combined with the above-mentioned metal oxide sintered bodies 4 a and 4 b and the hard resin body 1. , 1, and are hardened at room temperature or by heating.尙, opposing end faces of the sintered body ⁴ a, 4 b, the outer periphery of the metal member ^{1 1,} hard resinous body 1 7 hard檨脂body 1 in the gap portion between 9, 1 9 liquid before嫘Chakusuru Pour resin 20. In addition, this resin 20 does not dissolve in the coating liquid. Any resin may be used.

With this resin-coated structure, all the gaps in the connection section ¹り are filled, the coating liquid does not enter the inside, and the resin itself does not dissolve in the coating liquid. . Connection

A sufficient strength can be obtained because the strength of 1 mm is compensated by the adhesive strength of the curable resin 20 and the repulsive strength of the hard resin bodies 17, 1, 1 for bending and the like.

 An electrode using ferrite or magnetite as the metal oxide sintered body having the above structure was used as an anode in a click-type electrodeposition coating under the same conditions as in Example 4. After continuous use for about two years, when the electricity was examined, no abnormalities were found in the joints, and the resulting electrodeposition film was always normal and preferred.

 It should be noted that the electrode bonding structure of the present invention can be applied not only to the knives-type electrodeposition electrode, but also to other objects.

Example ό

In this example, the joint structure between the electrode and the lead is shown. FIG. 10 shows a side view of the electrode, and FIG. 11 shows a new view of the main part.

 Reference numeral 4 denotes an electrode body, which is made of a rod-shaped metal member 11 such as copper, iron, stainless steel, etc., and a conductive material 15 such as lead, solder, conductive adhesive, and a hollow body around the rod-shaped metal member 11. A metal oxide sintered body 4 a is coated, and a coated lead wire 、, for example, ό 100 V cross-linked polystyrene green vinyl resin is provided thereon via a connecting portion 5. A cable, a bullet ^; 緣, a vinyl storage cable, etc. are connected.

If the connection part 21 is described in more detail, a male screw part 11a is provided on the upper surface of the metal member 11, and this part is provided with nuts 25 and 25. The lead wire connection crimp 24 is fixed. Then, the crimping portion 24 a of the crimp terminal 24 is crimped by a conductor 2, from which the coating layer 25 of the lead 22 is removed, for example, by crimping a copper twisted wire. As a result, the electrode body ⁴ and the coated lead wire 22 are connected.

The outer periphery of this state is a tube made of Teflon, polychlorinated vinyl, etc., between the electrode 4 and nuclear lead, 22]. Jo hard fat it 2 7 is inserted, in its conductive Daidaitai ⁴ 11, stepped portions 2 7 a hand off b down the inner I¾, anti, and揷入the rubber of any ϋ Li in g 2 ^8, metal Tsuzumika烧^ body ⁴ a outer circumference and at the same time makes contact ¾ to of, ¾ Ke was to circle Tan緣^ to screw 2 ⁷ b, the same ingredients-shake Russia down, Ri'm etc. Po Li垤化bi two Lumpur Zi screws in a hollow cap shape 2 9 a the provided hard core: Aburatai ^{2 9} are allowed to嫘看a. Ri by the screwing of this hard resin body 2 ^9, 0 Li down click ^{'2 8} ... is pressed Ri by the tip of Waso, the exterior of the hard銜脂body 2 7 and the metal oxide sintered body 4 a Make sure there are no gaps. On the other hand, on the side of the coated lead wire 22, the female screw part 27 b provided in the inner green similarly has the same tef. A hard resin body 30 provided with a hollow screw 3Qa is attached to the outer horse in the form of a hollow cap made of a metal, a polychlorinated valve, or the like.

 After fabricating the structure in this way, a liquid curable resin S 1, for example, a two-part curable epoxy resin, polyester resin, polyvinyl chloride sol The hardening liquid resin such as the above metal oxide sintered ^ 4a and hard S "

2 ^9, 2 sky隱部your good beauty coating layer of the coated lead wire 2 2 of 7

25, conductor 2ό, terminal E 24, nut 23, pour into the gap between the male screw 11 a of the metal member ¹¹ and the hard material SO, 27, at room temperature Or it has been cured by heating. The resin 31 may be a liquid or a zole, and may be any orange oil which is not eluted in the coating solution.

 By this lubrication process, all the spaces between the connection parts 21 are buried, the internal parts do not come into direct contact with the liquid, and good electrical insulation and liquid tight packaging are achieved. Obtainable . Even if the coating lead (22); is immersed in the liquid, the only part of the current flowing to the coating liquid is the metal oxide ^ binder 40.

The above-mentioned electrode is applied to the thion-type electronic painting method ■ "-^ For use, for example, as shown in FIG. 12 or FIG. 15, it is used in a state of being immersed in a Xio tank.

As in the case of Example ⁴ , using a power tube u- ³⁰ (trade name, manufactured by Nippon Paint Co., Ltd.) as a paint, applying a DC voltage of 250 to 500 V, For example, even if the object to be coated 5 is an automobile body, the inner surface of the inner surface that is a box-shaped wipe, such as a member on the floor, is used even if the painted object 5 is an automobile body. The results were good. Also, if the this filtrate and was compared with the case where it was name rather using the electrode to Sosoko portion Remind as in the ^first 2 figures, the same conditions are also DOO in, full α Ryobume down bar The thickness of the film obtained on the inner surface was better than that of using an electrode, and it was preferable. Further, in order to check the durability of the electrodes, electrodeposition coating was performed continuously for about one year under the same conditions as in Example 4, and when each electrode was observed, it was confirmed that the metal compound compound 4a portion was observed. However, there was no problem, and there was no abnormality in the coated lead wire 22 immersed in the liquid and the S: S processed part of the connection 21. There was no. In addition, there was no elution in the coating solution and no foreign matter was mixed, and the obtained coating film was always of high quality and preferred.

 Although the above embodiment has been described with reference to the electrode of the power chain ¾ 、 painting S, the present embodiment is not limited to this, and it can be used as the electrode of 5 & 侔 看 看 看 そ の そ のAnd Q

Claims

The scope of the claims

 (1) Cathode type electrode for electrodeposition coating made of sintered metal oxide having conductivity.

 (2) The electrode according to claim 1, wherein the metal oxide sintered body is magnetite or ferrite.

 (3) The claim 1 wherein the metal oxide sintered body is a cylindrical body with one flange closed, wherein a metal member is inserted as a core into the cylindrical body, and is fixed with a conductive material. The electrode as described.

(4) The electrode according to claim 3, wherein the metal member is a stainless steel rod.

 (5) Metal-strengthened ^ Combination cylinder: A cylinder ^ divided into at least two values, and these cylinders are inserted into one metal member and fixed. 4. The electrode according to claim 3, wherein a cylindrical hard resin body is fitted over the two cylindrical bodies so as to be fitted over the joining portion, and is integrated with a hardening resin.

 (6) A covering lead is connected to the top of the electrode, the reading portion is covered with a tubular hard resin 、, and the KJ is solidified into a KJ with a hardening resin filled in the ¾. The electrode o 'described in paragraph 3 of

(7) A method for electroless electrodeposition coating, wherein the electrode according to claims 1 to 4 is used as an anode.