JPH05200938A - Resin composite type damping metal plate - Google Patents

Abstract

PURPOSE:To obtain the title damping metal plate having high bonding strength at room temp. and highly holding damping capacity in the vicinity of room temp. by bonding and laminating a viscoelastic resin compsn. containing an inorg. powder component with a specific particle size to two metal plates in a specific thickness. CONSTITUTION:A resin composite type damping metal plate is obtained by bonding and laminating a viscoelastic resin compsn. containing at least one or more kind of an inorg. powder component within a condition range represented by formulae I-IV [wherein h is the thickness (mm) of a resin layer, d is the average particle size (mm) of the inorg. powder, n is the number of inorg. powder particles contained in a resin volume 100 h (mm<2>)] between two metal plates. The viscoelastic resin used in the resin composite type damping metal plate is amorphous from the aspect of the enhancement of damping capacity and contains at least one or more kind of the inorg. powder component. As the resin, for example, amorphous polyester, polyimide, an amorphous polyolefin resin, a blend of various resins or a copolymer are designated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to machines, buildings, vehicles,
The present invention relates to a resin composite type vibration damping metal plate having a laminated structure which is used as a structural member of home electric appliances or the like or a part thereof.

[0002]

2. Description of the Related Art In recent years, the problems of noise and vibration have become a social problem as pollution due to the development of transportation facilities and the approach of houses to factories, and noise is also improved in the workplace to improve the working environment. And tends to regulate vibration. Corresponding to such a tendency, the vibration damping performance, that is, the vibration energy of the member itself that generates noise is converted into thermal energy for the metal material that is the noise source or the vibration source, and the vibration velocity or vibration amplitude is attenuated. The function of reducing acoustic emission,
Furthermore, it is required to improve its function. Based on such a demand, as one of the damping materials exhibiting such performance, a composite damping material having a multilayer structure in which an intermediate layer having viscoelasticity is sandwiched between metal layers has been conventionally proposed. This composite type vibration damping material is used in automobile oil pans, engine covers, dash panels, hopper chute parts, home appliances, stoppers for transportation equipment, other vibration reducing members for metal working machines, and precision machinery that requires vibration prevention. It has been studied and adopted in the structural members, etc.

Generally, the damping performance of such a composite damping material depends on the performance of the viscoelastic intermediate layer constituting the intermediate layer. When this damping performance is represented by a loss coefficient, it is known that this damping performance exhibits a peak characteristic at a certain constant temperature, and that it is most effective to use it near this peak characteristic temperature.

Conventionally, as a viscoelastic composition constituting the viscoelastic intermediate layer of such a composite type vibration damping material, polyester alone (Japanese Patent Laid-Open No. 50-143880) or polyester with a plasticizer added ( JP-A-51-937
70), polyurethane foam alone (JP-A-51)
No. 91981), or a polyamide simple substance (JP-A-56-159160), an ethylene-vinyl acetate copolymer simple substance (JP-A-57-34949), polyvinyl butyral, or polyvinyl butyral and polyvinyl acetate. Compounded with a plasticizer and a tackifying substance (JP-B-55-27975), a copolymer of an isocyanate prepolymer and a vinyl monomer (JP-B-5).
2-26554), or Japanese Patent Publication No. 39-1245.
1, Japanese Patent Publication No. 45-34703, Japanese Patent Publication No. 62
The copolymer and the like disclosed in Japanese Patent Publication No. 74645 are known.

[0005]

By the way, the composite type vibration damping material has, first of all, a high loss coefficient, and the adhesion between the viscoelastic intermediate layer composed of the viscoelastic composition and the metal layer. Although high strength is required, the composite vibration-damping material produced by the conventional viscoelastic composition described above has a problem in any of its performances and is not sufficiently satisfactory. In particular, in order to exhibit high performance at around room temperature, it is necessary to set the glass transition temperature to below room temperature, and with conventionally known resins, when the glass transition temperature is lowered, the adhesive strength is significantly reduced, and therefore, high adhesion is achieved. There is a problem in that it cannot be used in applications requiring high properties.

[0006]

In view of such a situation, the present invention has a high adhesive strength at room temperature (for example, a shear adhesive strength of 80 kgf / cm ² or more) and maintains a high vibration damping performance near room temperature. (For example, the loss factor is 0.1 or more)
As a result of intensive studies on the viscoelastic resin composition for damping material, the present invention has been achieved.

That is, a resin composite type characterized in that a viscoelastic resin composition to which at least one kind of inorganic powder component is added is adhered and laminated between two metal plates in a condition range shown by the following formula. It is a damping metal plate.

[0008]

[Equation 2]

[0009]

The viscoelastic resin used for the resin composite type vibration damping metal plate of the present invention is amorphous from the viewpoint of improving the vibration damping performance, and is one containing at least one or more kinds of inorganic powder components.
As the resin, for example, amorphous polyester, amorphous polyamide, polyimide, polyurethane, polyurethane urea, polyurea, acrylic resin, epoxy resin, vinyl acetate resin, amorphous polyolefin resin, or a blend of various resins Examples thereof include copolymers and the like. In the present invention, a cross-linking agent such as a polyfunctional isocyanate or epoxy may be used in consideration of the flow characteristics at high temperature.

The inorganic powder component added to the viscoelastic resin may be surface-modified with various surface modifiers for the purpose of improving interfacial adhesion with the resin. Examples of the surface modifier include silane coupling agents, titanate coupling agents, fatty acids and amines.

The present invention is characterized in that a viscoelastic resin composition obtained by adding at least one or more kinds of inorganic powder components to the above viscoelastic resin is adhesively laminated between two metal plates. By using a composition in which at least one kind of inorganic powder component is added to a viscoelastic resin as an adhesive for the composite type vibration damping material, an adhesive strength higher than the adhesive strength of the resin alone at room temperature can be obtained and the vibration damping performance can be improved Can be secured in.

A wide variety of inorganic powders can be applied, but calcium carbonate, talc, silica, kaolin, carbon black, alumina, titanium oxide, zinc white, graphite, mica, etc., have desirable characteristics. Have. That is, it is an inorganic powder that has little influence on the glass transition point of the viscoelastic resin and does not adversely affect the vibration damping performance.

In the embodiment, a phosphate-treated steel sheet is used as the type of the steel sheet, but the type is not limited to this. Specifically, a phosphate-treated steel sheet, a chromate-treated steel sheet, a zinc-treated steel sheet, a stainless steel sheet, a surface-treated steel sheet such as an organic coated steel sheet, or a plain steel sheet having a degreased surface may be used. Furthermore, a metal plate other than a steel plate can be used. Further, the plate thickness is not particularly limited, but 3.2 m is required in order to fully exhibit its vibration damping characteristics.
m or less has desirable characteristics.

The relationship between the average particle size of the inorganic powder component and the number of powder particles, and the thickness of the resin layer {n (d / 2) ³ } / h is 0.4.
By setting it in the range of 8 to 5.25, it is possible to obtain an adhesive strength higher than that obtained in the case of the resin alone. If {n (d / 2) ³ } / h is less than 0.48, no improvement in adhesive strength is observed, which is not preferable. The inorganic powder particles may be dispersed in the resin and have a function of relaxing stress concentration and improving strength, but if the number in the unit volume is too small or the particles are too small, the effect is small. Therefore, it is considered that when {n (d / 2) ³ } / h becomes smaller, the improvement in adhesive strength cannot be recognized. If {n (d / 2) ³ } / h exceeds 5.25, the vibration damping performance in the low temperature range is deteriorated, which is not preferable. It is considered that this is because if the number of powder particles in a unit volume increases, the rigidity of the resin composition becomes too high and the deformation necessary for viscous damping is impeded.

If the average particle diameter of the inorganic powder component exceeds 30 μm, the effect on the adhesive strength becomes small, which is not preferable. It is considered that this is because as the particle size of the inorganic powder particles increases, the stress concentration on the particle surface increases, and fracture, peeling or flow occurs at the interface between the resin and the particles.

The average particle size of the inorganic powder component is 4 of the resin thickness.
When it exceeds 1/100, the effect on the adhesive strength is similarly reduced, which is not preferable. As the particle size approaches the thickness of the resin layer, the stress concentration at the interface between the powder particles and the resin when the resin layer undergoes shear deformation increases. Therefore, as in the case where the particle size is increased, as the ratio between the particle size of the inorganic powder particles and the resin thickness approaches 1, the stress concentration on the particle surface increases, and fracture or separation or flow at the resin-particle interface occurs. It is considered that this is more likely to occur and the adhesive strength is also reduced. Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples.

[0017]

EXAMPLE A base resin made of epoxy cross-linked polyester, and a viscoelastic resin prepared by adding an inorganic powder component to the basic resin is sandwiched between two phosphate-treated steel plates to form a composite vibration-damping metal plate of the present invention. Created. The shear adhesive strength is JIS
It was measured at 20 ± 2 ° C. according to K 6850. Also, T
The peel strength was measured at 20 ± 2 ° C according to JIS K 6854. Further, for the damping performance, the loss coefficient at 10 ° C. at a vibration frequency of 500 Hz was obtained by a method using mechanical impedance. The components and properties of Examples and Comparative Examples are shown in Tables 1 to 5.

Examples 1 to 8 are samples to which calcium carbonate was added. Examples 9 and 10 are samples to which talc was added. Example 11 is a sample to which calcium carbonate and talc are added. In Examples 1 to 11, a significant improvement in adhesive strength is recognized as compared with Comparative Examples 1 and 2 in which no inorganic powder is added.

Comparative Example 3 is an example in which {n (d / 2) ³ } / h is less than 0.48. The increase in adhesive strength is not so great. In Comparative Example 4, {n (d / 2) ³ } / h was 5.
25 or more examples. Although an improvement in adhesive strength is recognized, the damping performance at 10 ° C. is greatly reduced. Comparative Example 5
Is an example in which the resin thickness is 5 mm or more. A decrease in shear bond strength is observed. Comparative Example 6 is an example in which the average particle diameter of the inorganic powder component exceeds 1/4 of the resin thickness. Although the shear bond strength is improved, the increase is small.
Comparative Example 7 is an example in which the average particle size of the inorganic powder component exceeds 30 μm. Although the shear adhesive strength is higher than that of Comparative Example 2, the increase width is not so large. Comparative Example 8 is an example in which the resin thickness is 10 μm or less. This is inferior in both adhesive strength and damping performance.

[0020]

[Table 1]

[0021]

[Table 2]

[0022]

[Table 3]

[0023]

INDUSTRIAL APPLICABILITY As described above, the present invention uses a viscoelastic resin in which an inorganic powder component having a particle size in a specific range is added to an intermediate resin layer for exerting a vibration damping effect, and thus has excellent vibration damping property. Further, it is possible to obtain a resin composite type vibration damping metal plate having high adhesive strength.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Setsuo Sasaki 1-4-1 Tsujido Kandai, Fujisawa-shi, Kanagawa Kyodo Yushi Co., Ltd. (72) Inventor Shinichi Nagato 1-4-1 Tsujido Kandai, Fujisawa, Kanagawa Kyodo Yushi Co., Ltd In the company

Claims (1)

[Claims] 1. The following (1) to (4) between two metal plates.
A resin composite type damping metal plate, comprising a viscoelastic resin composition to which at least one or more kinds of inorganic powder components are added in an amount satisfying the formula, which is adhesively laminated. [Equation 1]