JPH06262724A - Preparation of composite metal sheet with excellent adhesive properties - Google Patents

Abstract

PURPOSE:To provide a method for manufacturing a composite metal sheet with excellent adhesive properties wherein importance is attached to processability. CONSTITUTION:In a composite metal sheet wherein a laminated body is prepd. by bonding two metal sheets M1 and M2 to a viscoelastic adhesive resin and in a method for manufacturing the composite metal sheet wherein a resin is placed between two sheets of the metal sheets M1 and M2 and they are press- bonded, a resin layer is respectively formed on both faces of facing faces of the metal sheets to be bonded and the ratio of thicknesses of the resin layers t1 and t2 is in the range of 0.05<=t1/t2<=0.2. the thickness (t1) of the resin layer formed on one face side of the facing metal sheets to be bonded is pref. t1>=1.0mum. It is possible thereby to prevent micro boiling phenomenon on the bonding surface from generating and to improve stably adhesive strength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite metal plate having a viscoelastic adhesive resin interposed between two metal plates and having excellent adhesiveness. More specifically, the present invention is used for soundproofing. The present invention relates to a method for producing a vibration-damping steel plate or a composite metal plate that requires vibration-damping properties and workability such as a lightweight laminated steel plate.

[0002]

2. Description of the Related Art In recent years, reduction of noise generated by vibrations in various machines and transportation facilities, and weight reduction of heavy machinery such as automobiles have become an important issue as an energy saving measure. Has come to use a metal plate having a vibration damping property, that is, a composite vibration-damping metal plate.

For example, an automobile oil pan, a dash panel, a hopper chute, a general-purpose engine cover,
A composite damping metal plate is used in the vibration reduction part of a metalworking machine.

For automobiles, trains, and other heavy objects, weight reduction is considered as an energy saving measure.
Lightweight laminated metal sheets have shown promise.

[0005]

[Problems to be Solved by the Invention] Such a composite metal plate is
It has a laminated structure and is composed of two or more metal plates and an adhesive resin layer which is inserted between the metal plates and entirely joins the metals. The adhesive strength of the two metal plates is workable. Will become an important issue. Therefore, various improved techniques have been proposed.

For example, Japanese Patent Application Laid-Open No. 1-73381 discloses that the thickness ratio of the resin thick layers formed on the opposite surfaces of the two metal plates to be adhered is equal to or close to that. Therefore, there is a drawback that a phenomenon called "armpit" occurs in the resin during thermocompression bonding and the adhesive strength becomes unstable. Also, in terms of manufacturing process, the cost is increased due to resin drying conditions and the like.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a method of manufacturing a composite metal plate excellent in adhesiveness with emphasis on workability and the like. To provide.

[0008]

As a means for solving the above problems, the present invention provides a composite metal plate in which two metal plates are laminated with a viscoelastic adhesive resin to form a laminate. In the method for producing a composite metal plate by interposing the resin between a plurality of metal plates and thermocompression bonding, the resin layers are formed on both surfaces of the adhered metal plate surfaces facing each other. The gist is a method for producing a composite metal sheet having excellent adhesiveness, characterized in that the ratio of the thicknesses t ₁ and t ₂ is in the range of 0.05 ≦ t ₁ / t ₂ ≦ 0.2.

[0009]

[Action]

The present invention will be described in more detail below.

According to the present invention, a viscoelastic adhesive resin layer is formed on the adhesive surfaces of two metal plates facing each other during thermocompression bonding. However, a metal plate having the resin layer thinly formed on one surface, and the metal plate The composite metal plate having excellent adhesion is obtained by thermocompression bonding with a metal plate having a thick viscoelastic adhesive resin layer formed on the opposing surface thereof.

At this time, the ratio of the thicknesses t ₁ and t ₂ of the viscoelastic adhesive resin formed on the two metal plates is 0.05 ≦ t ₁ / t ₂ ≦ 0.2.
By controlling the temperature within the range, the heating temperature during crimping increases the wettability effect between resin surfaces, which is indispensable for bonding conditions, and there is no cracking, and crimping is performed in a better condition, and a composite with excellent adhesiveness. A metal plate is obtained.

Explaining with reference to the drawings, prior to thermocompression bonding, as shown in FIG. 1, one of the two adherent metal plate surfaces M ₁ and M ₂ facing each other is adhered metal plate surface M. _A viscoelastic adhesive resin having a thickness t ₁ is formed on ₁ , and the other adhered metal plate surface M ₂
Then, a viscoelastic adhesive resin is formed to a thickness t ₂ (t ₁ <t ₂ ). Then, as shown in FIG. 2, these metal plates are thermocompression bonded.

At that time, the thickness (t ₁ ) of the resin layer formed on one surface side of the adhered metal plate surfaces facing each other is t ₁ ≧ 1.
It is preferably 0 μm. When there is no formation of the resin layer on one side of the adhered metal plate surfaces facing each other, that is, in thermocompression bonding of the viscoelastic adhesive resin layer forming surface and the metal plate surface,
Since the surface wettability required for adhesiveness is poor, the adhesive strength is weak and unstable. Similarly, even if the thickness is t ₁ <1.0 μm, the adhesive strength tends to be weak. In order to obtain the thickness (t ₁ ≧ 1.0 μm) of the resin layer, it should be noted that the control of the resin thickness becomes unstable in a normal resin coater and the effect of improving the adhesiveness cannot be obtained.

The resin thickness of the adhesive surface of the two metal plates is
If the resin is formed with an equal thickness or a resin thickness close to it, the resin will be dried from the surface side of the coating film during drying after resin coating.
(Curing). In the case of the present invention (different thickness coating material), the dry (curing) area is deep in the thick film material as shown in FIG.
The thin film material is shallow. That is, as shown in FIG.
The difference thickness coating material reduces the entire cured area when the two sheets are bonded. Therefore, it is possible to prevent a decrease in the wettability effect between resin surfaces during thermocompression bonding.

On the other hand, in the case of coating a thick film having a uniform thickness or a thickness close to it, the dry (curing) area of the surface becomes large, so that the wettability effect between resin surfaces during thermocompression bonding decreases. For this reason, the adhesive strength of the composite metal plate is lowered, and especially the resin ductility (the magnitude of the shear displacement) is reduced, resulting in poor workability. Further, when the thick film-coated ones are heated and pressure-bonded to each other as described above, a microscopic void phenomenon called “armpit” occurs in the resin, and the adhesive strength often becomes unstable.

It should be noted that other conditions in the production of the composite metal plate, such as the material and thickness of the metal plate, the material and characteristics of the viscoelastic adhesive resin, the pressure and temperature during heat bonding, are particularly limited. Not done.

Next, examples of the present invention will be described.

[0019]

[Example 1]

Two 0.4 mm thick steel plates and a polyester-based viscoelastic adhesive resin were used to heat and press-bond with a hot press to produce a composite metal plate. In order to remove dirt and oil on the surface of the steel sheet, the steel sheet was degreased with trichlene and washed with alkali degreasing. The polyester resin was prepared by adjusting the resin viscosity and the like with a necessary solvent and controlling the thickness of the resin layer formed on the steel plate surface by a bar coater coating method to a predetermined thickness.
Regarding the resin thickness, the total thickness of t ₁ and t _{2 on} the adhered steel plate surfaces facing each other was set to 50 μm.

As comparative materials, an example in which no resin was formed on the adhesive surface of one side of the steel sheet, an example in which the resin sheets on the opposite steel sheets to be adhered had an equal thickness, and an example in which the thickness was close to that were produced.

Table 1 shows the resin layer forming thickness conditions and the results of the adhesive strength by the T peel test.

As is clear from Table 1, the invention example No. 2
Excellent adhesive strength was obtained in all of Nos. 6 to 6. on the other hand,
The adhesive strength of the comparative example No. 1 in which the resin layer is formed on only one side of the adhesive surface of the two metal plates is extremely low. Conversely,
In Comparative Examples Nos. 7 to 8 in which the resin is formed on the adhesive surfaces of two metal plates to have the same thickness or a thickness close thereto, a microscopic cracking phenomenon occurs on the adhesive surfaces, and the adhesive strength by the T peel test is shown. Is low.

[0024]

[Table 1]

[0025]

Example 2

Next, the resin coating thickness, the state of surface drying (curing) at the time of drying after coating and its influence were examined. In the measurement of the surface-hardened region (depth) at the time of drying after coating the resin, the cross section of the resin film thickness was observed with an electron microscope. The relationship between the resin coating film thickness and the surface hardening depth after drying was as shown in Table 2.

[0027]

[Table 2]

That is, a uniform thickness coating (25 μm) metal plate × 2
In the case of one sheet (comparative example), the resin surface hardening depth is 10 μm each
Since these two surfaces are pressure-bonded, the total hardened area is 20 μm. On the other hand, in the case of the difference thickness coating metal plate × 2 sheets (Example of the present invention), the curing depth on one side (45 μm) is 12
However, the curing depth on the opposite side (5 μm) is 2 μm, and the total cured area is 14 μm.

A shear tensile test was conducted to confirm that the effect of the difference in the hardened region appears as a difference in resin ductility (displacement amount) in the shear tensile test. 35 mm (width) x 200 mm from that manufactured as a composite steel plate in the shear tensile test
A test piece cut into (length) was used. The measurement is based on JIS
According to K6850.

The test results are shown in FIG.
As shown in the displacement (ductility) diagram, it can be seen that the differential thickness coating material having a small surface-hardened region (Example of the present invention) has considerably excellent adhesiveness. The resin thickness of the upper metal plate is 10
~ 200μm, the resin thickness of the lower metal plate is 1 ~ 10μm
Is preferred.

[0031]

As described in detail above, according to the present invention,
In terms of the manufacturing process, it is possible to manufacture a composite metal sheet having stable adhesive strength and no micro-defects and excellent adhesiveness, and it has an advantage that it can be used in all industrial fields.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a resin-formed state of opposing metal plate surfaces to be bonded before thermocompression bonding in the present invention.

FIG. 2 is a schematic cross-sectional view showing a composite metal plate after thermocompression bonding in the present invention.

FIG. 3 is a diagram for explaining a surface drying (curing) area during drying of a resin film after resin coating, which is the case of differential thickness coating (the present invention).

FIG. 4 is a diagram for explaining a surface drying (curing) area when a resin film is dried after resin coating, in the case of uniform thickness coating (conventional method).

FIG. 5 is a load-displacement (ductility) diagram when applying shear deformation by a shear tension test.

Front page continuation (72) Inventor Takashi Saito 1 Kanazawa-cho, Kakogawa-shi, Hyogo Kobe Steel Works Kakogawa Works

Claims (2)

[Claims] 1. A composite metal plate in which two metal plates are laminated with a viscoelastic adhesive resin to form a laminated body, and the resin is interposed between the two metal plates and thermocompression bonded. In the method for producing a resin, the resin layers are respectively formed on both surfaces of the adhered metal plate facing each other, and the ratio of the thicknesses t ₁ and t ₂ of the respective resin layers is 0.05 ≦ t ₁ / t. _A method for producing a composite metal sheet having excellent adhesiveness, characterized in that the range is ₂ ≦ 0.2. 2. The method according to claim 1, wherein the thickness (t ₁ ) of the resin layer formed on one surface side of the adhered metal plate surfaces facing each other is t ₁ ≧ 1.0 μm.