JPS6140149A - Method of bonding metallic plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for adhering metal members, especially steel plate members, of vehicle bodies such as automobiles, airplanes, and ships, home appliances, and various other devices.
More specifically, the present invention relates to an adhesive sealing method which is extremely suitable for adhering metal members, particularly steel plate members, particularly hemmed parts.

Conventionally, metal structures are made by welding and joining metal plates formed into a predetermined shape for each member to create a structure with a predetermined shape.
After that, most things are usually painted.

These metal structures are usually bonded and sealed using liquid compositions made of various rubbers and resin compositions before joining processes such as welding or painting processes, and especially for parts with complex shapes, such as hem. This is an indispensable process when processing parts, etc.

For example, taking an automobile body as a typical example, the automobile body is made by welding and joining press-formed steel plates for each member to create a so-called white body, which is then subjected to degreasing treatment and chemical conversion treatment, and then electrodeposition painting. It is manufactured through a series of lines including a surface coating process consisting of an intermediate coat and a top coat. Then, an adhesive composition made of the above-mentioned liquid composition is applied to hem-processed parts of hoods, doors, etc. to perform adhesion and sealing.

However, these compositions are originally insulators, and adhesives and
When used for sealing, no electrodeposition film is formed,
For this reason, it is difficult to form a coating film at the interface between the resin adhesive or sealing layer and the metal plate, resulting in undesirable problems such as rust formation. In order to prevent this, a method using a composition containing conductive powder such as metal powder has been developed, but the heat resistance and durability are reduced, and an oil film etc. adheres to the adhesive and sealing parts. In some cases, there were problems such as poor adhesion, poor workability, and seal leakage.

In addition, the following difficulties arise when using these compositions. In other words, if these compositions are processed after being applied, such as hemming, the thickness of the coating film will not be constant, resulting in uneven adhesion or uneven sealing properties, which may cause rust. In addition, due to the pressure applied during processing, excess composition may ooze out, making it necessary to boil the product manually, resulting in significantly poor workability. Particularly in the case of compositions using thermosetting resins, this wiping operation is essential in order to stabilize shrinkage during thermosetting.

The present inventor has been conducting extensive research in order to resolve the difficulties that arise when using the above-mentioned conventional compositions, and in this research, instead of the conventional means of applying the composition, adhesive We came up with a completely new idea of adopting a new method of pasting sheets, and as a result of further research based on this idea, we found that the main ingredient is epoxy resin, preferably a certain epoxy resin, and a conductive filler and hardened epoxy resin. The present inventors have discovered that the above-mentioned conventional difficulties can be overcome by using an adhesive sheet prepared by blending the adhesive sheet with the adhesive agent, and have now completed the present invention. That is, in the present invention, an adhesive sheet containing an epoxy resin, a conductive filler, and a hardening agent is attached to a metal plate in advance, and after being processed as necessary,
This relates to a method for adhering metal plates, which is characterized by applying electrodeposition coating and then curing the adhesive sheet when heating and baking the coating film.In particular, as an epoxy resin, (a) By using a liquid or semi-solid epoxy resin having chains, or (b) a mixture of a liquid or semi-solid epoxy resin with a high molecular weight thermoplastic resin derived from bisphenol A and epichlorohydrin, an oil film can be formed. It can also provide excellent adhesion and sealing properties to metal members to which it has adhered.

According to the present invention, since the method of pasting an adhesive sheet is adopted, it is possible to apply a certain amount of adhesive uniformly, and the film thickness of the adhesive does not change during processing. There is very little chance that the adhesive composition will protrude when pressure is applied, and workability can be significantly improved. Furthermore, by simultaneously curing the adhesive sheet during the painting baking process, it is possible to form an adhesive sealing layer with excellent mechanical strength, heat resistance, and durability, and the adhesive strength is also uniform and stable. In addition, when the epoxy resin (a) or (b) is used as the epoxy resin, it has excellent initial adhesion even to oil film metal plates, and based on this, the conventional drawbacks can be avoided. In addition, the formed adhesive sealing layer has good spot weldability and electrodeposition coating properties, so it does not cause rust at the interface with the metal plate and has an excellent appearance.

The present invention will be described below with reference to the drawings, taking up the case of forming a hemmed portion of a steel plate as a representative example of the method of the present invention.

Figures 1 and 2 show an example in which the method of the present invention is applied to the hem processing portion of an automobile body. The hem is processed to form a hem processed part as shown in FIG.

In this invention, first, an adhesive sheet (3) is attached to a steel plate forming the hemmed portion shown in FIG. The application site may be either the inner plate (1) in Fig. 1a or the outer plate (2) in Fig. 1, and is appropriately selected depending on the application location. Also, the width of the pasting is set in advance to be the same width as the overlapping part of the inner plate and the outer plate of the hem processing part to be formed, or to the extent that it slightly protrudes. At this time, these steel plates are coated with anti-corrosion oil, but if the epoxy resin of (a) or (b) is used as the epoxy resin, it can be directly attached to these oil film steel plates. After that, the hem is assembled and molded according to the method.

As the epoxy resin constituting the adhesive sheet used in the present invention, a normal epoxy resin can be used, but preferably (a) a liquid or semi-solid epoxy resin having a long alkyl chain, or (b) a liquid or semi-solid epoxy resin that can be used at room temperature. A liquid or semi-solid epoxy resin blended with a high molecular weight thermoplastic resin derived from bisphenol A and epichlorohydrin is used, and these epoxy resins have hydrophobic groups as constituent molecules, so they have a high resistance to oil and fat bones. has good compatibility and contributes to improving initial adhesion with oil-film steel sheets. Also, since it contains a relatively long chain component, the resin has a high cohesive force and excellent sheet forming ability.

The long alkyl main chain has about 5 to 50 carbon atoms, preferably about 8 to 30 carbon atoms. Such resins include epoxy resins such as polyethylene glycol, polypropylene glycol, α・ω-glycol, a block copolymer of ethylene oxide and propylene oxide, and the like, which are produced by reacting epichlorohydrin with the carbonyl group of polyacrolein or polyvinyl ketone. - Epoxy resin derived from reaction of ylide; dimer acid,
Trimer acids, unsaturated higher fatty acids or the like.

Examples include epoxy resins derived from esters.

Among the above epoxy resins, epoxy resins derived from long chain dimer acids having 10 to 20 carbon atoms are preferably used, and examples include epoxy resins derived from linoleic acid dimer and epichlorohydrin. When these resins are used, particularly good results can be obtained in terms of adhesion to oil surfaces, and adhesive sheets with excellent water resistance, chemical resistance, etc. can be obtained.

Note that it is possible to use an ordinary epoxy resin together with the above-mentioned epoxy resin having a long alkyl main chain in a proportion of 50% by weight or less of the total.

The high molecular weight thermoplastic resin derived from bisphenol A and epichlorohydrin used in the present invention is one having an average molecular weight of at least 10,000 or more including repeating units represented by the following structural formula. A typical commercially available thermoplastic resin is a phenoxy resin manufactured by Union Carbide Co., Ltd. (having a repeating unit of 82 to 1 repeating unit per molecule).
23, softening point 212, average molecular weight 25,000-3
5,000). These high molecular weight thermoplastic resins derived from bisphenol A and epichlorohydrin are used in combination with liquid or semi-solid epoxy resins.

In this case, the thermoplastic resin is usually used in an amount of 5 to 70% by weight, preferably 10 to 40% by weight, and is rarely used alone. The liquid or semi-solid epoxy resin used in combination is not particularly limited, but those having the above-mentioned long-chain alkyl chain are not usually used.

The liquid or semi-solid state of the epoxy resin used in the present invention usually exhibits properties at room temperature. The curing agent is preferably one that is stable at room temperature and exhibits activity at high temperatures, particularly nitrogen-containing compounds that decompose at high temperatures to produce at least one active hydrogen-containing amine, such as monourea,
It is preferable to use volurea, hydrazide, thiourea, etc. Specifically, 3-(P-chlorophenyl)=
Examples include 1,1-dimethylurea, 2,4-bis(NN-dimethylcarbamide)toluene, and dicyandiamide.

Of course, it is also possible to use other curing agents such as acid anhydrides, imidazoles, imidacillins, etc.
Specific examples of these include anhydride 4, maleic anhydride, dodecylsuccinic anhydride, hexahydrophthalic anhydride,
Methylnadic anhydride, pyromelliftic anhydride, hensifhenonetetracarboxylic anhydride, dichlorosuccinic anhydride,
Chlorenedisocyanic anhydride, 2-methylimidazole, 2
-ethyl-4-methylimidazole, 2-phenylimidal, 2-undecylimidazole, 2-heptadecyl imidazole, 2-ethylimidazole, 2-isopropylimidazole, 2,4-dimenal imidazole,
2-phenyl-4-methylimidazole, 2-methylimidacillin, 2-ethyl-4-methylimidacillin, 2
-7 enylimidazoline, 2-undecylimidacilline, 2-heptadecyl imidacilline, 2-ethylimidacilline, 2-isopropylimidapurine, 2,4-dimethylimidacilline, 2-phenyl-4- Examples include methylimidacillin.

The type and amount of these curing agents are such that the adhesive sheet is almost cured when the electrodeposited coating is heated and baked (even if it is not completely cured at this point, it can be heated and baked in the intermediate coating and top coating processes in the subsequent process). can be set as appropriate depending on the conditions of heating and baking. The general blending amount is 1 part of 0.5 to 130 iri, preferably 5 to 50 MM per 100 parts by weight of epoxy resin.
It is about 100%.

In this invention, it is important to mix a conductive filler, and such fillers include metal powders such as silver, palladium, copper, aluminum, iron, and 2.7 Kel, carbon black, graphite, etc. Examples include inorganic substances other than metal powders.

The amount used varies depending on the type, shape, particle size, etc. of the conductive filler, but it is usually 10 to 10 parts by weight per 100 parts by weight of the epoxy resin.
It is used in a proportion of about 700 parts by weight, preferably about 20 to 200 parts by weight. Further, the shape, particle diameter, etc. may be appropriately selected and determined from a wide range, and examples thereof include granular, acicular, and scaly shapes. If it is granular, the particle size is approximately 0.
．． 1 to 400μ, preferably about 0.5 to 200μ, in the case of a needle, the diameter (shorter one) is about 0.1 to 500μ, preferably about 0.5 to 300μ, and an aspect ratio of 5 to 200
, preferably about 10 to 150. In the case of scales, the thickness is about 0.1 to 500 μm, preferably 0.1 to 30 μm.
0 μ and aspect ratio of 5 to 200, preferably 10 to 1
It is about 50.

In addition to the above-mentioned components, various compounding agents can be added to the conductive resin composition for adhesion and sealing according to the present invention, if necessary. For example, phenyl-β-naphthylamine, diphenyl-P
- Stabilizers and anti-aging agents such as phenylene diamine, di-tert-butyl-4-methylphenol, paraphenylphenol, calcium stearate, and dilaurylthiodipropionate are added to diesters, ester gums, etc. for the purpose of improving adhesion. Fillers such as clay, talc, calcium carbonate, silica, barium carbonate, and asbestos can be added to the alkyd resin and coumaron resin for the purpose of preventing the composition from sagging and reducing costs. Other coloring agents may also be added. The blending amount of these is 5 to 30 parts per 100N of epoxy resin.
The amount may be approximately 0 parts by weight.

To obtain the conductive adhesive resin sheet used in this invention, first add a curing agent and a conductive filler to the epoxy resin, and add various other additives as necessary to the epoxy resin at room temperature or at a temperature at which hardening does not occur. A conductive resin composition is prepared by mixing using a mixing stirrer, various kneaders, two or three mixing rolls, etc. at a temperature of (may occur slightly). Next, this composition may be formed into a sheet in an uncured or semi-cured state using a coater such as a roll coater or a knife coater, various press molding, or an extrusion molding machine. A substrate can be inserted to improve the reinforcing effect. Suitable examples of such a base material include porous materials such as cheesecloth, coarse sheets made of various materials, nets, woven fabrics and nonwoven fabrics made of various materials.

In particular, in the present invention, the following effects can be obtained by using a heat-shrinkable base material alone or in combination with a non-shrinkable base material. Figures 3 and 4 show an adhesive sheet using a heat-shrinkable base material alone as a base material, and Figures 5 and 6
The figures each show an example of hemming using an adhesive sheet using a combination of a heat-shrinkable base material and a non-heat-shrinkable base material. When hot air is blown from the direction of the arrow as shown in Figure 3, the pressure of the wind causes the adhesive sheet (3) to curve as shown in Figure 4, and at the same time, the heat of the hot air causes the heat-shrinkable base material (5) to heat up. Since shrinkage occurs, pasting of the adhesive sheet H31 as a post-work becomes easier. In Figures 5 and 6, the third
Similar to Figures 4 to 4, the adhesive sheet (3) is bent toward the inner plate (1) by wind pressure and hot air, but at this time, the non-shrinkable base material (6
) becomes a restraining layer and bends further toward the inner plate (1), further improving workability. Furthermore, as shown in Fig. 7, when hemming is performed using a normal base material (i.e., non-heat shrinkable base material) as an adhesive sheet, the outer panel (2), the adhesive sheet (3), and the inner panel (1) are used. However, in the case of an adhesive sheet using a heat-shrinkable base material as the base material, as shown in Figure 8, the thickness of the adhesive sheet increases due to heating.
During hem processing, resin is injected into the void (7) and the outer plate (2)
This is extremely advantageous.

In this invention, the adhesive sheet is used as an inner plate (1) and an outer plate (2).
) to form a hem-processed part, and then degreasing, chemical conversion treatment, and electrodeposition coating are performed according to conventional methods. and an electrodeposition coating film formed on the surface of the adhesive sheet (3).

As the electrodeposition paint, conventionally known ones can be used as they are, and for example, epoxy resins, acrylic resins, etc. are used.

Next, the electrodeposited coating film (4) is heated and baked to improve the adhesion of the film (4) to the steel plate surface, while the resin layer of the adhesive sheet C3) is almost cured to develop adhesive and sealing properties. . Also, due to the conductivity of the resin, the electrodeposition coating property is good even on the interface X and the narrowed part Y between the adhesive and the steel plate, which originally have poor coverage of electrodeposition coating, and an excellent antirust effect can be obtained. Furthermore, it is completely cured by heating and baking after the intermediate coating and top coating in the post-process, forming a cured adhesive/sealing layer with excellent heat resistance, mechanical strength, and durability. The rust prevention effect of Y is further enhanced.

After forming the electrodeposited coating film (4) in this way, the inner and outer panels fi+, (2) intermediate coating and top coating are applied according to the conventional method, and then passed through a predetermined cavity A to improve the rust prevention effect. An excellent automobile body can be obtained.

Metal plates to which the method of the present invention can be applied include plates made of various metals or alloys thereof; typical examples include iron or its alloys, such as steel, aluminum or its alloys, copper or its alloys, etc. In particular, various steel plates can be exemplified as preferred. Typical examples of steel sheets include hot-rolled steel sheets, cold-rolled steel sheets, galvanized steel sheets, zinc alloy-plated steel sheets, and pre-coated steel sheets.

A typical example of bonding these metal plates is bonding metal plates during hemming, but the method of the present invention is not limited to this hemming process, and can be used for a wide variety of adhesives, seals, etc. Applies to. For example, examples thereof are shown in FIGS. 9 and 10.

Examples of this invention will be described below. In addition, in the following, parts shall mean parts by weight.

Example 1 Epikote #871 (manufactured by Yuka Shell Co., Ltd., dimer acid-modified epoxy resin) 80 parts, Epi:l-) #1001 (manufactured by Yuka Shell Co., Ltd., bisphenol A type solid epoxy resin) 2
0 parts were melt-mixed in a melting pot to obtain a viscous composition. To 100 parts of this composition were added 5 parts of dicyandiamide (manufactured by Nippon Carbide Co., Ltd., epoxy resin curing agent), 5 parts of CUREZOL 2MZ-AZ INE (manufactured by Shikoku Kasei Co., Ltd., epoxy resin curing agent), 100 parts of graphite powder, and 3 parts of asbestos powder. A resin composition is obtained by blending and kneading with a regular mixing roll, and this is mixed with glass floss (
A conductive adhesive sheet in an uncured state having a thickness of 0.3 mm* was obtained by forming it into a sheet using a direct pressure press on a film separator using ECM60M' (manufactured by Unitika UMG).

Next, in assembling a vehicle body made of cold-rolled steel plates with a plate thickness of 0.6 to 0.81, the above adhesive sheet is pasted on the end face of the inner plate fil in advance as shown in Fig. 1a, and then hemming is performed, and the inner plate is (1) and the outer plate (2) were integrated via an adhesive sheet (3), and spot welding was performed to form a hemmed portion. This car body was subjected to degreasing treatment, chemical conversion treatment, and electrodeposition coating treatment, and then baked in a baking oven at 180° C. for 20 minutes.

Note that an epoxy resin type paint was used as the electrodeposition paint.

The adhesive sheet caused a hardening reaction by heating and baking as described above, resulting in uniform and strong adhesion and sealing. Furthermore, the adhesive-exposed surface was completely covered with an electrodeposition coating, further improving sealing properties. After that, 1 coat each in the intermediate coating and top coating process.
Baking was performed at 40° C. for 30 minutes, and the adhesive was almost completely cured by this baking.

Vehicle bodies manufactured in this way are less susceptible to rust.
, the corrosion resistance was extremely good.

Cooling 2 85 parts of Epikote #828 (manufactured by Yuka Shell Co., Ltd., bisphenol A type liquid epoxy resin) and 15 parts of phenoxy resin (manufactured by Union Carbide Co., Ltd., mentioned above) were heated to 180°C in a mixer equipped with a heating heater. The mixture was heated to uniformly melt and mix to obtain a viscous composition. To 100 parts of this composition, 1.5 parts of dicyandiamide (Example 1f!: same), 3-(P
-Chlorophenyl)-1.1 dimethyl urea (manufactured by Maruji Biochemical Co., Ltd., epoxy resin curing agent) 3 parts, graphite powder 40 parts, and zinc powder 40 parts were blended and kneaded using a normal mixing roll to obtain a resin composition. I got it. Next, the above composition was coated onto a vinylon cheesecloth #100 (manufactured by Kuraray Co., Ltd.) substrate using a roll coater to create an adhesive sheet with a thickness of 0.4 μ.

Next, as in Example 1, in assembling a vehicle body made of cold-rolled steel plates with a thickness of 0.6 to 0.8 u+, the above-mentioned adhesive sheet was attached to the end surface of the outer panel (2) as shown in Figure 1. After that, hem processing is performed and the inner plate [1] and outer plate (2) are glued together)
+3) and spot welded to form a hem processing part. This car body was subjected to the same treatment and electrodeposition coating as in Example 1, and then baked. The adhesive sheet underwent a curing reaction during the heating and baking process, resulting in a uniform and strong adhesive seal. A coating film was also formed on the adhesive surface.

Afterwards, a post-paint was applied and the adhesive was almost completely cured.

Vehicle bodies manufactured in this way are less susceptible to rust.
, the corrosion resistance was extremely good.

Example 3 Epikote #871 (manufactured by Yuka Shell Co., Ltd., dimer acid-modified epoxy resin) 80 parts, Epi:I-)"#1001 (
A viscous mixture was obtained by melting and mixing 20 parts of bisphenol A type solid epoxy resin (manufactured by Tib Shell Co., Ltd.) in a melting pot. To 100 parts of this composition, 5 parts of dicyandiamide, 5 parts of Curazole 2MZ-AZINE (same as in Example 1)
100 parts of graphite powder, and 3 parts of asbestos powder were blended and kneaded with a normal mixing roll to obtain a resin composition, which was then mixed into a heat-shrinkable base material (manufactured by Toyobo Co., Ltd., 1., T, T-P) Formed into a sheet shape with direct pressure press on a t-mediated film separator to a thickness of 0.3
An uncured conductive adhesive sheet consisting of ms was obtained.

Next, in assembling a car body made of cold-rolled steel plates with a plate thickness of 0.6 to 0.8 fi, as shown in Fig. 3, the adhesive sheet (3) is pasted in advance on the end face of the inner plate (11). Blowing hot air at 150℃ for 1 minute, the wind pressure causes
Further, due to the shrinkage of the heat-shrinkable base material (5), it becomes as shown in FIG. The shrinkage rate in the width direction at this time was 20%. Afterwards, hemming was performed, and the inner plate (11) and outer plate (2) were integrated via an adhesive sheet (3), and spot welding was performed to form a hemmed part.This car body was degreased, chemically treated, and electrically A coating treatment was performed, and then the coating was heated and baked in a baking oven at 180° C. for 20 minutes.The electrodeposition coating used was an epoxy resin-based coating.

The above heat baking process caused a hardening reaction in the adhesive sheet, resulting in uniform and strong adhesion and sealing.

Furthermore, the exposed surface of the adhesive was completely covered with an electrodeposition coating, further improving sealing properties. Also, the void part (7) in Figure 7
was also completely sealed. Thereafter, in the intermediate coating and top coating steps, heating baking was performed at 140° C. for 30 minutes, and the adhesive was almost completely cured by this heating baking.

Vehicle bodies manufactured in this way are less susceptible to rust.
, the corrosion resistance was extremely good.

Example 4 80 parts of epoxy Epicor #871, Epicor #828 (manufactured by Yuka Shell Co., Ltd., bisphenol A type liquid epoxy resin)
20 parts were melt-mixed in a melting pot to obtain a viscous composition.

To 100 parts of this composition, 1.5 parts of dicyandiamide, 3-
3 parts of (P-chlorophenyl)-1,1 dimethyl urea (manufactured by Maruji Biochemical Co., Ltd., epoxy resin curing agent) and 75 parts of graphite powder were blended and kneaded using a normal mixing roll to form a conductive resin composition. I got it.

80 parts of the epoxy Epicoat 1828 of No. 2 and 20 parts of the phenoxy resin were heated to 180° C. using a mixer equipped with a heating heater and uniformly melted and mixed to obtain a viscous composition. This composition 1
00 parts, 1.5 parts of dicyandiamide, 3 parts of 3-(P-chlorophenyl)-1.1 dimethyl urea, and 75 parts of graphite powder were mixed with a normal mixing roll to obtain a conductive resin composition. Ta.

Next, the first epoxy resin is formed into a sheet using a direct pressure press onto a film separator with a heat-shrinkable base material (manufactured by Toyobo Co., Ltd., 1.T, T-P) interposed therebetween to a thickness of 0. 25m
A conductive adhesive sheet was obtained.

In addition, a second epoxy resin was molded in the same manner as above through vinylon cheesecloth #100 (manufactured by Kuraray Co., Ltd.), which is a base material that hardly causes heat shrinkage, and a conductive adhesive with a thickness of 0.25 m was formed. Got a sheet.

After that, both conductive adhesive sheets were pasted together to form an integral laminate.

Next, in assembling a car body made of cold-rolled steel plates with a plate thickness of 0.6 to 0.8, the above adhesive sheet is pasted in advance on the end face of the inner plate (1) as shown in FIG. Similarly, hot air is blown at about 150° C. for 1 minute, and the air pressure also has the effect of shrinking the heat-shrinkable base material (5). At this time, the 6th
As shown in the figure, the adhesive sheet (3) is oriented so that it always wraps around the inner plate flll side, so the base material that hardly undergoes heat shrinkage becomes the constraining layer, and the second epoxy resin is the same as the first epoxy resin. Since it has more flexibility than other adhesive sheets, it becomes an adhesive sheet that warps in one direction.

Thereafter, hemming was performed, and the inner plate (1) and outer plate (2) were integrated via an adhesive sheet (3), and spot welding was performed to form a hemmed portion.

This car body was subjected to degreasing treatment, chemical conversion treatment, and electrodeposition coating treatment, and then baked in a baking oven at 180° C. for 20 minutes.

Note that an epoxy resin-based electrodeposition paint was used as the electrodeposition paint.

The adhesive sheet caused a hardening reaction during the heating and baking process, resulting in uniform and strong adhesion and sealing. Furthermore, the exposed surface of the adhesive was completely covered with an electrodeposition coating, further improving sealing properties. Furthermore, the cavity (7) shown in FIG. 7 was completely sealed, as shown in FIG. 8.

After that, the temperature is increased to 140℃ for the intermediate coating and top coating process.
1. Heat baking is performed for 30 minutes. The adhesive was almost completely cured by this heating and baking.

The car body manufactured in this manner was resistant to rust and had extremely good corrosion resistance.

[Brief explanation of the drawing]

1 to 10 show examples to which the method of the present invention is applied. In addition, the numbers in the drawings indicate the following, respectively. (1), Inner plate < 2), Outer plate (3), Adhesive sheet (4), Electrodeposition coating (5), Heat in adhesive sheet Shrinkable base material (6),
,,Non-shrinkable base material in adhesive sheet (7),,,,Void area (and above) I11Z Photo 2■ Procedure? …Author (method) December 24, 1982

Claims (1)

[Claims] 1. An adhesive sheet containing an epoxy resin, a conductive filler, and a hardening agent is pasted on a metal plate in advance, processed as necessary, and then electrodeposited, and then this coating is applied. A method for bonding metal plates, which comprises curing the adhesive sheet when baking the film. 2. The epoxy resin is a liquid or semi-solid epoxy resin having a long alkyl main chain, or a liquid or semi-solid epoxy resin is blended with a high molecular weight thermoplastic resin derived from bisphenol A and epichlorohydrin. The adhesive method according to claim 1, which is an adhesive sheet having excellent oil surface adhesion. 3. The bonding method according to claim 1 or 2, wherein the conductive filler is made of metal powder and/or an inorganic material such as carbon black or graphite. 4. The bonding method according to any one of claims 1 to 3, wherein the adhesive sheet is formed by impregnating and integrating a woven fabric or a nonwoven fabric. 5. The adhesion method according to any one of claims 1 to 4, wherein the adhesive sheet is formed by impregnating a heat-shrinkable base material alone or a heat-shrinkable base material and a non-shrinkable base material. 6. The bonding method according to any one of claims 1 to 5, wherein the metal plate is a steel plate, an aluminum or its alloy plate, or a copper or its alloy plate. 7. The bonding method according to any one of claims 1 to 6, wherein the processing is to form a hem processed portion. 8. The bonding method according to any one of claims 1 to 6, wherein the metal plate is a steel plate of an automobile body or the like, and the processing is processing to form a hem processing part.