JP2566086B2 - Method for manufacturing resin composite type vibration damping metal plate - Google Patents

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 vibration-damping metal plate having a three-layer structure comprising a resin layer having a vibration damping effect and two metal plates sandwiching the resin layer from both sides.

[0002]

2. Description of the Related Art In recent years, with the widespread use of industrial machines and household electric appliances, noise and vibration generated from various devices have come to be regarded as a problem from the viewpoint of health and hygiene or environmental protection.
In particular, the spread of transportation equipment such as automobiles is remarkable, and the noise generated by them is a serious social problem.

As one of the measures against this, there is the use of a vibration damping metal plate such as a vibration damping steel plate. A vibration-damping metal plate uses a vibration-damping alloy, a two-layer type (unconstrained type) in which a vibration-damping material is attached to one side of the metal plate, and a core resin is sandwiched between two metal plates. There are layer type (constraint type) and the like, and they are being adopted in a wide range of fields. Particularly, the composite restraint type vibration-damping metal plate (hereinafter, simply referred to as a vibration-damping metal plate) attenuates vibration by utilizing internal friction due to shear deformation of the viscoelastic material of the intermediate layer, and is the most In addition to being excellent in vibration damping performance, there is an advantage that secondary processing such as press working can be performed as it is and it can be handled in the same manner as ordinary steel plates.

It is generally known that the vibration-damping metal plate has better workability when the tensile shear bond strength between the resin layer and the metal plate is larger. This tensile shear adhesive strength has a correlation with Tg (glass transition temperature) of the resin for the intermediate layer,
The higher the Tg, the better. Further, the temperature range exhibiting the damping property is also influenced by the Tg of the intermediate layer resin, and the higher the Tg, the higher the temperature range.

Therefore, when vibration damping at a relatively high temperature is required as in an automobile engine oil pan, by selecting a resin having a high Tg as the intermediate layer resin,
It is possible to obtain a vibration-damping metal plate having both workability and vibration-damping property. On the other hand, if you want to exhibit vibration damping performance at room temperature, you will inevitably use a resin with a low Tg, but at the same time the tensile shear bond strength between the resin and the steel sheet will be low, and workability will be insufficient, so the design Despite the above considerations, there has been a demand for the development of an intermediate layer resin having the contradictory properties of low Tg and tensile shear bond strength at room temperature.

As one of the solutions, a method of blending a resin having a high Tg and a resin having a low Tg has been proposed. For example, in JP-A-63-202446, a polyester resin having a Tg of 47 ° C. and a polyester resin having a Tg of −15 ° C. are dissolved and blended in an organic solvent, and a melamine resin is added as a crosslinking agent. Vibration resistance and tensile strength at room temperature, such as polyester resin with Tg of -11 ° C blended with polyester resin of 10 ° C, polymer epoxy resin with Tg of 86 ° C blended with polyester resin with Tg of -15 ° C, etc. A method for producing a vibration-damping metal plate having both shear adhesive strength is described.

A polymer blended with such an organic solvent shows good results as an intermediate layer resin for a vibration-damping metal plate, but there is a risk of environmental pollution due to the organic solvent at the manufacturing stage. Furthermore, when polymer blending polyester resins with each other or blending polyester resin with another resin, the solution may become cloudy and incompatible depending on the mixing ratio, and such a polymer blend is initially mixed. Even if it looks like, phase separation easily occurs with time.

In addition, a method using a highly crystalline polyester resin or polyurethane resin can be considered. By using these, even if the Tg is low, since the film has tensile strength, it is possible to manufacture a vibration-damping metal plate for room temperature having a tensile shear adhesive strength between a resin and a steel plate. Does not dissolve, so a special coating device is required, and the high melt viscosity makes it difficult to coat uniformly with a thickness of 40 to 50 μm. When attempting to apply by heating and melting, a curing agent such as isocyanate and melamine resin reacts with the resin during heating and melting, and the melt viscosity further increases, and the coating operation becomes more difficult.

[0009]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and provides a resin composite type metal plate having both high vibration damping property at a relatively low temperature or room temperature and high tensile shear adhesive strength. It is intended to provide a manufacturing method.

[0010]

The present invention is a method for producing a resin composite type vibration-damping metal plate in which a vibration-damping resin layer is sandwiched between two metal plates. Alternatively, both sides are coated with a mixed resin liquid in which two or more kinds of resin dispersions having different glass transition temperatures are mixed, dried, and then two metal plates are bonded to each other via the resin coated surface. To do.

[0011]

[Operation] According to the present invention, 2 having different glass transition temperatures
As a dispersion in which fine particles of a resin are physically dispersed and contained in water, and a mixture of two or more kinds of resins is used, the resin particles are mixed in a dispersed state, so that the compatibility is low. The resins can be easily mixed with each other, and since the resins are attached immediately after drying the water, there is little risk of phase separation of the resins.

In the present invention, two kinds of resins having different glass transition temperatures are copolymerized as described in JP-B-39-12451, or two or more kinds of resins are not used as a simple mixture, but phase A vibration-damping metal plate showing vibration-damping properties over a wide temperature range can be obtained by mixing polyester resin dispersions with different Tg's with poor solubility or mixing polyester resin dispersions with poor compatibility with phenoxy resin dispersion and polyurethane resin dispersion. It can also be manufactured.

The dispersion of various resins is manufactured, for example, as follows. Phenoxy resin 100 g of phenoxy resin dissolved in a mixed solvent of 100 g of toluene and 100 g of methyl ethyl ketone, 3 g of polyoxyethylene alkyl ether was added and dispersed in 200 g of water stirred with a disper, and then toluene and methyl ethyl ketone under reduced pressure were added. Is removed to obtain a dispersion of phenoxy resin, and water is further added to adjust the nonvolatile content to 30%. Polyester resin 100 g of polyester resin dissolved in 200 g of ethyl cellosolve is dispersed in 200 g of water stirred with a disper, and then ethyl cellosolve is removed under reduced pressure to obtain a polyester dispersion, and further water is added. And adjust the nonvolatile content to 30%. Polyurethane resin 100g polyurethane resin dissolved in 200g acetone, 4g nonylphenoxy polyoxyethylene ethanol
Disperse in 200 g of water stirred with a disper, remove acetone under reduced pressure to make a polyurethane dispersion, and add water to obtain a non-volatile content of 30%.
Adjust to.

Further, in the present invention, two kinds of resins are not simply used as a mixture as a core material resin, but by cross-linking them, only the tensile shear adhesive strength is significantly increased without lowering the vibration damping property. It is also possible, and as a result, a composite vibration-damping metal plate having both vibration-damping properties at around room temperature and tensile shear bond strength can be obtained. As a cross-linking agent,
Appropriate polyfunctional compounds such as amino resin, aziridine, carbodiimide, and epoxy resin may be used.

The amount of the cross-linking agent used is preferably in the range of 3 to 30 parts by weight based on 100 parts by weight of the resin. Further, it is effective to use paratoluenesulfonic acid or phosphoric acid for the amino resin and imidazole, phosphoric acid ester or the like for the epoxy resin as a reaction accelerator for the crosslinking reaction, because the curing proceeds rapidly. In order to impart weldability to the damping metal plate to be produced, nickel particles, iron powder, conductive fillers such as carbon fibers are mixed in the mixed resin solution before coating, or the mixed resin solution after coating is mixed. The conductive filler is contained in the resin layer by means such as spraying these onto the resin layer.

When the resin is applied to the metal plate, if the viscosity is too low and the resin is repelled on the metal surface and uniform application is difficult, polyvinyl alcohol, hydroxyethyl cellulose, polyacrylic acid can be used as a thickener. It is advisable to add an aqueous solution such as to increase the viscosity. These are also effective in preventing sedimentation when the conductive filler such as nickel particles is added.

In addition to the above, the resin of the present invention may be added with additives such as a filler, a heat deterioration preventing agent and a hydrolysis preventing agent, if necessary. The manufacturing process of the vibration damping metal plate of the present invention manufactured using the above resin is as follows, for example. Metal plates used on the outside include cold-rolled steel plate, zinc-based plated steel plate, aluminum-based plated steel plate, stainless steel plate, aluminum plate, etc. Let

As the resin, the above-mentioned various dispersions are mixed in a required type, and an aqueous solution of hydroxyethyl cellulose is added as a thickener to this, and if necessary, a crosslinking agent and a reaction accelerator are added to obtain a mixed resin solution. The concentration of the mixed resin liquid is determined by the type of resin, the thickness of resin, and the like. The mixed resin solution is applied to the surface, one surface or both surfaces of the metal plate whose surface is clean. It is convenient to apply by a coating device such as a roll coater, but spraying or other methods may be used.

Then, this metal plate is transferred to a drying step, the resin layer is dried at 100 to 250 ° C. for about 1 to 30 minutes, and after drying, two metal plates are stacked with the resin layer inside and 120 to 250
By thermocompression bonding at ° C, a strongly bonded composite vibration-damping metal plate can be obtained.

[0020]

【Example】

Example 1 50 parts by weight of polyester resin dispersion (Tg −10 ° C., molecular weight about 20,000, nonvolatile content 30% by weight) and phenoxy resin dispersion (Tg 100 ° C., molecular weight about 40,000, nonvolatile content 30% by weight) 50 A coating solution was prepared by adding 20 parts by weight of a 30% by weight aqueous solution of polyvinyl alcohol as a thickener.

As a cross-linking agent, 10 parts by weight of a 50% methyl ethyl ketone solution of butyl etherified melamine resin was prepared.
In addition, the coating type chromate treatment liquid reduces the amount of chromium deposited.
Prepare two 0.8 mm thick cold-rolled steel sheets that have been chromated to 50 mg / m ² and dry the resin solution on the chromate-treated surface with a bar coater to a resin thickness of 20 μm for each of these cold-rolled steel sheets. As applied.

Next, the two steel plates were dried in a hot air oven at 150 ° C. for 5 minutes, the resin surfaces of the taken out steel plates were overlapped with each other, and they were laminated with a heat roll at a temperature of 200 ° C. and a linear pressure of 10 kgf / cm. A damping steel plate was obtained in which 40 μm core resin was sandwiched between 0.8 mm thick steel plates. Example 2 70 parts by weight of polyester resin dispersion (Tg −10 ° C., molecular weight about 20,000, nonvolatile content 30% by weight) and 30 parts by weight of polyester resin dispersion (Tg 6 ° C., molecular weight 17,000, nonvolatile content 30% by weight) A coating solution was prepared by adding 10 parts by weight of an aqueous ammonium solution of polyacrylic acid (20% by weight) as a thickener.

Butyl etherified melamine as a cross-linking agent
5 parts by weight were prepared. Hereinafter, a vibration-damping steel plate was manufactured in exactly the same manner as in Example 1. Example 3 Polyester resin dispersion (Tg 6 ° C, molecular weight
17000, non-volatile content 30% by weight) 50 parts by weight, polyurethane resin dispersion (Tg 5 ° C, molecular weight about 20,000, non-volatile content 30% by weight) 50 parts by weight, and a hydroxyethyl cellulose aqueous solution (20% by weight) as a thickener. In addition, the coating liquid was prepared.

Of butyl etherified melamine as a cross-linking agent
A 50% methyl ethyl ketone solution was prepared. Hereinafter, a vibration-damping steel plate was manufactured in exactly the same manner as in Example 1 except that the heat roll temperature was 180 ° C. Comparative Example 1 Polyester resin dispersion (Tg 6 ° C, molecular weight
17000, non-volatile content 30% by weight) 100 parts by weight and ammonium polyacrylic acid solution as a thickener (20% by weight) 10
A coating solution was prepared by adding parts by weight.

5 parts by weight of butyl etherified melamine was prepared as a crosslinking agent. Hereinafter, a vibration-damping steel plate was manufactured in exactly the same manner as in Example 1. Comparative Example 2 An attempt was made to dissolve a highly crystalline polyester resin in 50% toluene and 50% methyl ethyl ketone, but it did not dissolve.

Comparative Example 3 A polyester resin (Tg −15 ° C., molecular weight about 20,000) and a polyester resin (Tg 20 ° C., molecular weight about 20,000) were dissolved in 50% toluene and 50% methyl ethyl ketone, respectively, and the weight ratio was 1 A mixture of / 3, 1/1, and 3/1 was applied onto a steel plate with a bar coater, and the resin layer was observed. As a result, it was opaque and the compatibility was poor.

The damping steel sheets produced by the above-mentioned examples and comparative examples are each used for measuring the loss coefficient.
mm x 300 mm, 25 mm for measuring tensile shear bond strength
Cut out to a size of 200 mm. The loss coefficient is measured by the central excitation method of the mechanical impedance method, and the tensile shear adhesive strength is measured by notching the cut specimen so that the overlap joint becomes 12.5 mm and pulling speed 5
It was carried out under the condition of mm / min.

The measurement results are shown in Table 1.

[0029]

[Table 1]

As can be seen from Table 1, the addition of a cross-linking agent gives a higher adhesive strength, but the level is sufficient for practical use without the addition of a cross-linking agent, and the cross-linking resin was used only in the portion requiring heat resistance. You can use them properly depending on what you use.
There is no problem in terms of vibration damping because the loss coefficient is 0.1 or more.

[0031]

Industrial Applicability According to the present invention, it is possible to use a resin having a poor compatibility in combination as a core resin, and as a result, it has a tensile shearing adhesive strength at around room temperature and an excellent vibration damping property. It became possible to manufacture damping steel sheets. Further, according to the present invention, the conventional roll coater and heat roll can be used as they are, and furthermore, a vibration-damping steel sheet having sufficient adhesive strength can be produced without using a cross-linking agent. It also has the advantage of being able to set a wide range of conditions, and has the advantage of requiring almost no organic solvent as compared with conventional solvent-type damping steel plate resins.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B32B 31/06 7148-4F B32B 31/06 // F16F 15/02 8917-3J F16F 15/02 Q

Claims (5)

(57) [Claims] 1. A method of manufacturing a resin composite type vibration-damping metal plate, comprising a vibration-damping resin layer sandwiched between two metal plates.
The one or both of the metal plates is coated with a mixed resin solution in which two or more resin dispersions having different glass transition temperatures are mixed and dried, and then the two metal plates are bonded via the resin-coated surface. A method for producing a resin composite-type vibration-damping metal plate, which is characterized by laminating them together. 2. The method for producing a resin composite type damping metal plate according to claim 1, wherein the resin dispersion is any of a phenoxy resin dispersion, a polyester resin dispersion, and a polyurethane resin dispersion. 3. The method for producing a resin composite type vibration damping metal plate according to claim 1, wherein a cross-linking agent is further added to the mixed resin liquid. 4. The method for producing a resin composite type vibration-damping metal plate according to claim 1, wherein a thickener is further added to the mixed resin liquid. 5. The method for producing a resin composite-type vibration damping metal plate according to claim 1, wherein the resin layer after applying the mixed resin solution contains a conductive filler.