JPH06316018A - Damping metallic plate and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide damping metallic plates which ensure excellent weldability without degrading damping property and adhesive property and a method for manufacturing the plates. CONSTITUTION:Damping metallic plates contain particle-like conductive filler. A porous resin layer having a porosity of 0.1-2.5% is adhered between the metallic plates. This damping metallic plate can be obtained in such a manner that a foaming resin containing particle-like conductive filler is interposed between the metallic plates, heated, and welded. Thereafter, gas is generated in the foaming resin so as to obtain the porous resin layer having the porosity of 0.1-2.5%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration-damping metal plate and a method for manufacturing the same, and more specifically, it is formed by sandwiching a foaming resin containing a particulate conductive filler between a pair of metal plates, followed by thermocompression bonding. By controlling the foaming reaction in the foamable resin to form a porous resin layer having a predetermined porosity, thus, it is excellent without lowering the adhesiveness between the metal plate and the resin layer and the vibration damping performance. The present invention relates to a vibration-damping metal plate that ensures weldability and a method for manufacturing such a vibration-damping metal plate.

[0002]

2. Description of the Related Art In recent years, a vibration-damping metal plate obtained by laminating and bonding a resin layer having elasticity between a pair of metal plates has attracted attention in various industrial fields such as automobiles and general vehicles from the viewpoint of noise suppression. Therefore, various improvements have been conventionally proposed. For example, JP-A-62-170338 introduces a non-adhesive portion where the adhesive is not partially applied when applying the adhesive to the adhesive surface between the metal plate and the elastic resin layer. Then, a vibration-damping metal plate has been proposed in which a bonding surface having a non-bonding portion is formed to improve vibration damping properties and specific rigidity.

Further, various weldable vibration-damping metal plates have been proposed in which a resin layer sandwiched between metal plates is mixed with a particulate conductive filler. However, in such a vibration-damping metal plate, even if the resin exhibits excellent vibration-damping performance when the conductive filler is not mixed, the vibration-damping performance can be improved by adding the conductive filler. Is known to decrease significantly. Moreover, in order to improve the weldability of the vibration-damping metal plate, the more the amount of the conductive filler compounded into the resin layer is increased, and the adhesion between the conductive filler and the metal plate is increased. The higher the value, the lower the damping performance. Generally, in order to improve the weldability of the damping metal plate, it is necessary to sufficiently adhere the metal plate and the conductive filler, but in this way, the metal plate and the conductive filler should be sufficiently adhered. If they are brought into close contact with each other, the metal plates are fixed to each other, so that the so-called shear deformation of the resin layer is hindered, and even if the resin originally has excellent vibration damping performance, as described above, The vibration-damping performance is significantly reduced by adhering the conductive filler between the metal plates while sufficiently adhering it to the metal plates.

[0004]

DISCLOSURE OF THE INVENTION The present invention is based on a technical point of view which is completely different from the conventional vibration-damping metal plate, and ensures excellent weldability without lowering the vibration-damping property and the adhesive property. It is an object of the present invention to provide a vibration-damping metal plate and a method for manufacturing such a vibration-damping metal plate.

[0005]

A vibration-damping metal plate according to the present invention contains a particulate conductive filler and has a porosity of 0.1 to 2.5.
% Of the porous resin layer is bonded between the metal plates. Further, such a vibration-damping metal plate according to the present invention is, according to the present invention, sandwiching a foamable resin containing a particulate conductive filler between metal plates to flatten the conductive filler while maintaining the foamability. After heat-pressing the resin between the metal plates, a gas is generated in the foamable resin, and the porosity is 0.1 to 1.
It can be obtained by being characterized by having a porous resin layer of 2.5%.

In particular, according to the present invention, when the foamable resin is applied between the metal plates as described above, the application thickness is in the range of 1.2 to 2 times the particle diameter of the conductive filler. It is preferable that That is, according to the present invention, a foaming resin containing a particulate conductive filler is thermocompression-bonded between a pair of metal plates, in which case the conductive filler is flattened in the pressure-bonding direction and then foamed. A small amount of gas foaming the conductive resin, and by setting the porosity to a predetermined range, by providing a fine gap between the fine particles of the conductive filler adhered to the metal plate and the metal plate. Thus, it is possible to obtain a vibration-damping metal plate having excellent weldability without lowering the vibration-damping property and the adhesive property.

In the present invention, nickel fine powder having a particle diameter in the range of 50 to 200 μm is preferably used as the particulate conductive filler. In particular, according to the present invention, the conductive filler is flattened and held between the metal plates together with the resin layer, and then the expandable resin is foamed by a slight amount of gas foaming to have a porosity within a predetermined range. As for the resin to be applied to the metal plate, in order to provide a fine gap between the metal plate and the fine particles of the conductive filler that are in close contact with the metal plate, the total coating thickness of the conductive filler is Particle size 1.2-
It is preferably twice, preferably 1.3 to 1.7 times, and usually about 1.5 times. Furthermore, according to the present invention, such a conductive filler is usually contained in a later-described expandable resin (before foaming) in a volume ratio of 0.5 to 6% by volume, preferably 0.8 to 5% by volume. It is included in the range of%.

In the present invention, the foaming resin is not particularly limited as long as it is a resin which can be foamed after sandwiching the foaming resin between a pair of metal plates and thermocompression bonding. For example, polyester resins containing blocked polyisocyanate and resins containing various foaming agents can be mentioned. The polyester resin containing this blocked polyisocyanate, when applied to the adhesive surface of the metal plate, adsorbs moisture in the air,
After that, the pair of metal plates are overlapped with each other, heat-pressed, and by the temperature rise during curing of the resin, the blocked polyisocyanate is thermally dissociated to generate a free isocyanate group, which reacts with the water content. By reacting, carbon dioxide gas is generated, and this carbon dioxide gas leads to the foaming phenomenon of the resin.

The foamable resin containing the conductive filler as described above depends on the particle diameter of the conductive filler contained therein,
Usually, 5 to 100 μm, preferably 10 to 6 on a metal plate.
The coating is performed so that the total coating thickness is in the range of 0 μm. According to the present invention, for example, when the polyester resin containing the blocked polyisocyanate as described above is used, it is possible to adjust the time until the metal plates are superposed after the resin is applied to the metal plates. Then, the amount of water adsorbed by the resin can be controlled, which makes it possible to control the foaming of the resin after the pair of metal plates are thermocompression bonded.

According to the present invention, when the foamable resin is foamed into a porous resin, the porosity thereof needs to be in the range of 0.1 to 2.5%. By controlling the porosity within this range, it is possible to secure weldability while suppressing deterioration of the damping performance and adhesiveness of the obtained damping metal plate. Generally, when a resin layer is heat-pressed between metal plates to form a damping metal plate, the thinner the coating thickness of the resin layer is,
That is, the higher the flatness of the conductive filler, the better the weldability of the vibration damping metal plate obtained. On the other hand, generally, the thinner the coating thickness of the resin layer is, the more the flattened conductive filler fixes the opposing metal plates, so that the vibration damping performance deteriorates.

According to the present invention, since the metal plate is released from the fixing by the above-mentioned conductive filler by foaming the resin layer, excellent weldability by the conductive filler is maintained. At the same time, it is possible to provide vibration damping performance that is almost the same as that of a conventional vibration-damping metal plate in which a resin layer containing no conductive filler is interposed between the metal plates.

[0012]

The present invention will be described below with reference to examples.
The present invention is not limited to these examples. Aluminum-killed steel sheet with a thickness of 0.4 mm was used as a skin steel sheet, and one of the steel sheets was coated with nickel fine powder with a volume ratio of 3.0% and a particle size of about 70 μm on one side of the bonded surface. A polyester resin containing a blocked polyisocyanate is contained in a bar coater in addition to 45
to a thickness of 5 μm (after drying), and a polyester resin containing a blocked polyisocyanate was applied to the adhesive surface on one side of the other steel plate to a thickness of 5 μm (after drying) with a bar coater (that is, coating to a steel plate). The thickness is 50 μm).

After heating the pair of steel plates at 160 ° C. for 2 minutes to dry them, they are left for a predetermined time (3 to 20 seconds), after which the pair of steel plates are superposed, roll-pressed and vibration-damped. It was a steel plate. For each damping steel plate thus obtained, the adhesiveness (T peel strength, JIS K
According to 6854. ), Vibration damping (loss coefficient, resonance method (by half-width method)) and weldability (electrical resistance value (μΩ) during welding) were measured. The results are shown in FIGS. 1 and 2.

FIG. 1 shows the relationship between the time until the resin is applied to the steel sheet and dried, and then the layers are laminated, and the porosity of the resin layers. Porosity can be controlled. FIG. 2 shows the relationship between the porosity of the resin layer and the T-peel strength, loss coefficient, and electric resistance value at the time of welding. According to the present invention, the porosity of the resin layer is 0.1 to 2.5. By setting the ratio to be in the range of%, it is possible to improve the vibration damping performance while ensuring the adhesiveness and the weldability. However, when the porosity of the resin layer is too large,
It is likely that the gap between the filler and the steel plate is opened too much, making it difficult to energize, so that the electrical resistance value becomes high.

FIG. 3 shows that the conductive filler is 1.0 to 1.0% by volume.
The relationship between the coating thickness of the resin contained in the range of 4.5% before foaming and the electric resistance value of the obtained damping metal plate is shown. The thinner the coating thickness of the resin is, that is, the conductive filler is The higher the flatness, the better the weldability of the vibration-damping metal plate obtained. Similarly, FIG. 4 shows that the conductive filler is 1.0 to 1.0% by volume.
The relationship between the coating thickness of the resin contained in the range of 4.5% before foaming and the loss coefficient of the obtained vibration-damping metal plate is shown. The addition of filler reduces the vibration-damping performance of the metal plate obtained. As the coating thickness of the resin is increased and the thickness of the resin is increased, the degree of flattening of the filler is reduced and the metal plate is fixed, so that the vibration damping performance of the obtained metal plate is deteriorated.

However, according to the present invention, the resin layer is foamed so as to have a predetermined porosity, whereby the fixing of the metal plate by the above-mentioned conductive filler is released, and thus the conductive filler is obtained. While maintaining excellent weldability due to
Compared with the conventional damping metal plate, the damping performance has been improved significantly,
Also, excellent adhesiveness can be ensured.

[0017]

As described above, according to the present invention, it is possible to obtain a vibration-damping metal plate having improved weldability while ensuring adhesiveness and vibration-damping performance. In particular, according to the present invention, since the resin layer has a foamed structure by gas foaming and has excellent vibration damping performance in the room temperature region, it is possible to obtain a room-temperature damping metal plate having weldability.

[Brief description of drawings]

FIG. 1 is a diagram showing a time period until a pair of steel plates are coated with a polyester resin containing a blocked polyisocyanate, dried, and then stacked, and a pair of steel plates thus treated are stacked and heat-pressed. 6 is a graph showing the relationship with the porosity of the porous resin in the vibration damping steel plate obtained in this way.

2 is based on FIG. 1 above, the porosity of the porous resin and the damping performance (loss coefficient), manufacturability (T peel strength) and weldability (electrical resistance value) of the obtained damping steel sheet. It is a graph which shows the relationship with.

[Fig. 3] shows the relationship between the coating thickness of a resin containing a conductive filler in the range of 1.0 to 4.5% by volume before foaming and the electric resistance value of the obtained damping metal plate. It is a graph shown.

FIG. 4 shows the relationship between the coating thickness of the resin containing the conductive filler in the range of 1.0 to 4.5% by volume before foaming and the loss coefficient of the obtained damping metal plate. It is a graph.

Front Page Continuation (72) Inventor Takashi Saito 1 Kanazawa-machi, Kakogawa-shi, Hyogo Kadogawa Works Kakogawa Works

Claims (4)

[Claims] 1. A porosity of 0, containing a conductive filler in the form of fine particles.
A vibration-damping metal plate comprising a porous resin layer of 1 to 2.5% bonded between the metal plates. 2. A method for producing a vibration-damping metal plate, comprising a porous resin layer adhered between metal plates, wherein a foaming resin containing a particulate conductive filler is sandwiched between the metal plates, and the conductive filling is performed. While flattening the material, the foamable resin is heat-pressed between the metal plates, and then gas is generated in the foamable resin to form a porous resin layer having a porosity of 0.1 to 2.5%. A method of manufacturing a characteristic vibration-damping metal plate. 3. When the foamable resin is applied between the metal plates, the thickness of the applied resin is set in the range of 1.2 to 2 times the particle diameter of the conductive filler. Manufacturing method of vibration-damped metal plate. 4. The method for producing a vibration damping metal plate according to claim 2, wherein the conductive filler is nickel fine powder.