JPH0230855B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vibration damping method for metal plates, etc.
Applied to building materials, steel plates for ships, and steel plates for automobile bodies,
The purpose is to provide a vibration damping method that can form a multilayer structure by heating in a coating line and obtain an excellent damping effect.

BACKGROUND ART Conventionally, thermally bonded bituminous damping materials have been mainly used to prevent vibrations and noise from structural members such as vehicles, machines, and building materials. However, this bituminous damping material has the disadvantage that its damping effect is significantly reduced at high temperatures, usually above 50°C. In order to improve this difficulty, the following measures have been developed. One method is to provide a metal restraining layer on the top of the damping material, and the second method is to increase the heat resistance of the damping material itself by blending a thermosetting resin or thermoplastic resin. The third method is disclosed in Japanese Patent Application No. 54-160300 (Japanese Unexamined Patent Publication No. 56-84950), which includes a lower layer having a plurality of convex portions of an arbitrary shape on one or both sides of a sheet, and an upper layer containing a binder. This is a method in which they are stacked in contact with each other.

The first method has extremely poor workability; for example, when gluing the damping material along the contours of the material to be damped, it must be manually pressed by hand each time, and the material to be controlled must be pressed manually. It is difficult to follow the shape of the vibration material, often creating voids, and it is difficult to sufficiently measure the improvement in the vibration damping effect. The second method has the disadvantage that the damping effect at room temperature decreases, and the third method has insufficient compatibility during heat fusion, especially when there are undulations in the damping material. When this is done, the fitting is particularly insufficient, the adhesion area is reduced after baking, the damping effect is lowered, and voids remain here and there, making it easy for cracks to form in these areas.

The present inventor has continued to conduct research with a view to resolving each of the drawbacks of the conventional methods described above, and in this research, a thermosetting resin layer was provided on one side of a conventional bituminous sheet vibration damping material. When this is laminated on a material to be damped, that is, a metal plate, and heated to fuse the bituminous layer onto the metal plate, which is the material to be damped, and to thermoset the thermosetting resin, it is necessary to achieve the intended purpose. found that it can be achieved. In particular, according to the research of the present inventor, when a bituminous sheet-like material and a thermosetting resin layer are used in combination as described above, unlike conventional normal bituminous sheet-like damping materials, In particular, when using a bituminous sheet material that does not contain any rubbery components, the damping effect based on the cooperative action with the thermosetting resin layer, especially the thermosetting resin layer with a specific viscosity, is extremely effective. It was found that The present invention has been completed based on these new discoveries, namely, the present invention forms a sheet material layer mainly made of bituminous material and a thermosetting resin layer on a metal plate in this order. The present invention relates to a method for damping vibrations of a metal plate, etc., characterized in that the metal plate is fused to the metal plate by heating, and the thermosetting resin layer is cured. contains substantially no rubber, and the thermosetting resin has a melt viscosity of 6.0×10 ² to 1.0× at 70°C.
The present invention relates to a vibration damping method characterized in that the above-mentioned processing is performed using a 10 ⁵ .

According to the present invention, an excellent vibration damping effect can be obtained not only in a low temperature range but also in a high temperature range, unlike conventional methods, and since the thermosetting resin layer has not yet been cured, complex shapes can be controlled. The vibration material can easily follow the material to be damped, such as the body of an automobile, and has excellent closeness.It also has excellent workability as it only needs to be placed at a predetermined position on the material to be damped. It is possible to completely eliminate all the conventional difficulties. In addition, in the method of the present invention, the thermosetting resin, especially the epoxy resin layer, which is more expensive than the bituminous layer, can be made considerably thinner than the bituminous layer, so the overall thickness of the damping material itself can be reduced. Therefore, the work becomes easier, the followability is further improved, and there is also the advantage that the cost is reduced.

The sheet-like material mainly made of bituminous material used in the present invention is formed into a sheet-like material with asphalt as the main component and appropriately blended with inorganic and organic fillers. Examples of fillers include calcium carbonate, mica, talc, asbestos, perlite, shirasu balloons, etc., and organic fillers include synthetic resins or fibers such as polyethylene, polyamide, and polyester, petroleum resins, synthetic rubber, natural rubber, and wood powder. , rice husk, hemp,
A specific example is hair. The amounts used are approximately 10 to 30 parts by weight of the inorganic filler and 10 to 20 parts by weight of the organic filler to 40 to 50 parts by weight of the asphalt.

In particular, in the present invention, it is preferable that the bituminous sheet does not contain any rubber component at all, and in particular, the bituminous sheet that does not contain a rubber component is used as a thermosetting resin, especially when the viscosity at 70°C is low.
6.0×10 ² to 1×10 ⁵ poise, especially when used in combination with an epoxy resin having the same viscosity, it exhibits an extremely excellent vibration damping effect. The thickness of this bituminous sheet is usually 0.2 to 10 mm, preferably 0.5 to 10 mm.
It is about 6 mm, and its viscosity is 3.0×10 ³ ~ at 100℃.
It is about 1.0×10 ⁵ poise.

As the thermosetting resin used in the present invention, it is possible to use ordinary thermosetting resins such as acrylic resin, urethane resin, and phenolic resin, but in the present invention, epoxy resin is preferably used. A sheet-like product is preferably used. Examples of such epoxy resins include various types such as ordinary bisphenol type, ether ester type, novolak epoxy type, ester type, cycloaliphatic type, and nitrogen-containing glycidyl ether type. Depending on the physical properties, one type can be used alone or two or more types can be used in combination.

In addition, as a curing agent, it is stable at room temperature and 80 to 200℃.
Those exhibiting activity in the temperature range are preferred, such as dicyandiamide, 4,4'-diaminodiphenylsulfone, imidazole derivatives such as 2-n-heptadecyl imidazole, isophthalic acid dihydrazide, N,N-dialkyl urea derivatives, N. ，
N-dialkylthiourea derivatives and the like are used. The amount of these hardening agents used is not particularly limited, but it is particularly preferable that in the baking process of the coating line of the damped material, the damping material first becomes thermally softened and follows the shape of the damped material, After that, it hardens and is fixed along the shape and is set appropriately according to the baking conditions so that it is completely hardened. Usually, 1 to 20 parts by weight of epoxy resin is
The percentage by weight is fine.

In addition to the above-mentioned epoxy resin and curing agent, various additives may be used as necessary to provide the composition with cohesive strength to the extent that it can be formed into a sheet.
Such additives include, for example, polyvinyl butyral, polyamide, polyamide derivatives,
Thermoplastic resins such as polyester, polystyrene, polyketone, high molecular weight epoxy resins derived from bisphenol A and epichlorohydrin, butadiene-acrylonitrile copolymers or derivatives thereof can be blended. The amount used is 5 to 100 parts by weight of epoxy resin.
It is best to use about parts by weight.

In addition to the above ingredients, in order to prevent sagging, control viscosity, and reduce costs, we use metal powders such as talc, clay, silica, alumina, barium sulfate, iron, lead, zinc, and aluminum, glass beads, perlite, glass balloons, and glass shorts. Fillers such as fibers may be blended, or pigments and dyes such as titanium oxide, carbon black, phthalocyanine blue, Mapico Yellow, and Watchene Red, various anti-aging agents, stabilizers, etc. may be blended.

The blending amount of these components may be about 5 to 500 parts by weight per 100 parts by weight of the epoxy resin.

To prepare a thermosetting resin layer consisting of such components, for example, an epoxy resin is added with a curing agent,
Add the above-mentioned optional ingredients as necessary, and prepare at room temperature or to the extent that hardening does not occur (as long as it is a small amount)
The resin composition obtained in this way may be mixed at a temperature using a mixing stirring pot, various kneaders, two or three mixing rolls, etc.
It can be formed into a sheet by any means such as press molding, various coatings, calendar rolls, extrusion molding, etc.

These thermosetting resin layers preferably have a viscosity of about 6.0×10 ² to 1×10 ⁵ poise at 70° C., and epoxy resins having the same viscosity are particularly preferred. The thickness of this thermosetting resin layer is about 0.02 to 5 mm, preferably about 0.05 to 3 mm.

In the present invention, the above-mentioned bituminous sheet layer and thermosetting resin layer are laminated in this order on a metal plate serving as a damping material, and then heated.
At this time, it is desirable from the viewpoint of workability to place a bituminous sheet on which a thermosetting resin layer has been formed on one side of the bituminous sheet on a metal plate serving as a vibration damping material, and then heat it. Heating has the effect of fusing the bituminous sheet onto the metal plate serving as the damping material and curing the thermosetting resin layer. Especially cars,
For things that are painted, such as building materials and steel plates for ships,
The heating during baking in the painting line can be used.

Although there are various types of metal plates as the material to be damped in the present invention, steel is preferable, and steel plates for automobile bodies are particularly preferable. The method of the present invention will be explained in more detail below using the steel plate for automobile bodies as an example.

In the vibration damping method according to the present invention, for example, after first assembling a car body, it is placed at a required location on a car body steel plate in a painting line before electrodeposition coating or the next intermediate coating. Although it can be applied to all places where a damping effect is required, when using the damping material according to the present invention, it can be applied to darts panels, propeller shafts,
Excellent effects can be obtained when used in tunnels, etc., which get hot during driving, or when used in complex shapes. Next, in a paint baking oven, the damping material is first softened by heat and conforms to the shape of the vehicle body. Thereafter, the thermosetting resin layer is cured, and is sufficiently adhered and fixed according to the shape.
Heating conditions vary depending on the baking furnace conditions or the time when the damping material is placed on the car body, but it is usually 100 to 200℃.
Fully cure in the paint line for between 20 and 120 minutes,
Close contact takes place. During construction, moisture and oil contained in the sheet, or air interposed between the steel plate and the sheet, due to the immersion process in electrodeposition liquid, etc., generate gas during heat fusion and cause blistering on the sheet surface. However, in the present invention, preferably By providing the through holes in the vibration damping material, the above concerns can be prevented and a highly reliable vibration damping method can be provided. The through holes to be provided should be approximately 3.0~
Preferably, the diameter is 1 to 10 mm at 5.0 cm intervals.

In the present invention, a thermosetting resin layer is mainly provided on a bituminous sheet, but an outer layer base material such as a resin sheet is further added to the outside of the thermosetting resin layer. You can. By adding this outer layer base material, it is possible to prevent the thermosetting resin from becoming sticky in an uncured state, and it becomes possible to store the sheet-shaped vibration damping materials in a stacked manner. It also prevents contamination for construction workers, has excellent workability, and is useful for protecting the surface of the cured film even after curing. The outer base material sheet may be a normal resin film such as polyester,
Vinyl chloride, nylon, polyethylene, polypropylene, etc. can be used, but adhesive polyolefin has the advantages of not impairing the conformability of the vibration damping material, having little shrinkage when heated, and adhering well to epoxy resins etc. after curing. EVA (ethylene-vinyl acetate copolymer) is particularly desirable. The thickness of the film in this case is usually preferably about 0.01 to 0.8 mm.

The present invention will be specifically described below with reference to examples. In the following examples, all percentages indicating the compositions of the epoxy resin layer and the bituminous layer are percentages by weight.

Example 1 A 1.5 mm thick bituminous sheet and a 0.3 mm thick epoxy resin layer were laminated on a 0.08 mm thick steel plate and heated at 70°C.
Heating was performed for 20 minutes to fuse the bituminous sheet to the steel plate and to cure the epoxy resin layer. The damping effect of this product was measured based on JASOM329.
The results are shown in FIG. However, the dotted line in Figure 1 is
This is the same as in Example 1, and the solid line shows the same steel plate damped using only a bituminous sheet. However, the compositions of the bituminous sheet and epoxy resin layer used are as follows.

<Epoxy resin layer> Epoxy resin…38.5% Barium sulfate and calcium carbonate…50% Iron powder…8% Hardening agent and hardening accelerator…3.5% <Bituminous layer> Straight asphalt…50% Talc and calcium carbonate…30% Nylon Fiber...5% Petroleum resin...10% Asbestos...5% As is clear from Figure 1, the method of the present invention exhibits a nearly constant vibration damping effect over a wide range of temperatures from 20°C to 60°C. It can be seen that in the case of only the quality sheet, the damping effect decreases rapidly as the temperature rises.

Example 2 In Example 1 above, the thickness of the bituminous sheet was
3.0 mm, and all other treatments were carried out in the same manner as in Example 1. The results are shown in FIG. It can be clearly seen from FIG. 2 that the same thing as in Example 1 is true.

Comparative Example 1 In the formulation of the bituminous layer in Example 1 above, the amount of talc and calcium carbonate was changed to 25%, and 5% of rubber was newly added, and the other conditions were the same as in Example 1. Processed. The results of the damping effect in this case are shown in FIG. 3A.

Comparative Example 2 In Example 1 above, an epoxy resin having a melt viscosity of 6×10 poise was used, and all other treatments were carried out in the same manner as in Example 1. The measurement results of the damping effect in this case are shown in FIG. 3B.

Comparative Example 3 In Example 1 above, an epoxy resin having a melt viscosity of 6×10 ⁶ poise was used, and the other conditions were the same as in Example 1. The results are shown in FIG. 3C.

[Brief explanation of drawings]

1 to 3 are graphs showing the relationship between temperature and damping effect.

Claims (1)

[Scope of Claims] 1. A sheet material layer mainly made of bituminous material and a thermosetting resin layer are formed in this order on a metal plate, and the thermosetting resin layer is heated and fused to the metal plate. In a vibration damping method in which the resin layer is hardened, the sheet material mainly made of bituminous material contains substantially no rubber, and the thermosetting resin is melted at 70°C. A method for damping vibrations of a metal plate, etc., characterized in that the viscosity is 6.0×10 ² to 1×10 ⁵ poise. 2. A sheet-like multilayer vibration damping material in which a thermosetting resin layer is preliminarily formed on one side of a sheet-like material mainly made of bituminous material is placed on a metal plate on both sides of the sheet-like material made of bituminous material. A vibration damping method according to claim 1. 3. The vibration damping method according to claim 1, wherein the thermosetting resin is an epoxy resin. 4. The vibration damping method according to claims 1 to 3, wherein the sheet material mainly made of bituminous material has a melt viscosity at 100° C. of 3.0×10 ³ to 1×10 ⁵ poise. 5. The vibration damping method according to claims 1 to 4, characterized in that an outer layer is further provided on the thermosetting resin layer. 6. Claim 1, characterized in that the bituminous layer, the thermosetting resin layer, and the outer layer provided as necessary are provided with holes penetrating almost the entire surface thereof.
The vibration damping method described in items 5 to 5. 7. The vibration damping method according to claims 1 to 6, wherein the metal plate is a steel plate for automobiles, building materials, and ships, and the heating is performed in a coating line for these.