JPH0230854B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration damping/sound insulating material and a vibration damping/sound insulating method using the same, and an object thereof is to have excellent shape conformability to a metal plate which is a material to be damped. At the same time, we also aim to provide vibration damping and sound insulating materials with excellent diagnostic and sound insulating properties.

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 top of the damping material, and the second method is to increase the heat resistance of the damping material itself by adding 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.

In the first method, the workability is extremely poor. For example, when gluing the damping material along the undulations of the material to be damped, it must be manually pressed by hand each time. It has the disadvantage that it is difficult to follow the shape of the material, often creating voids, and it is difficult to sufficiently measure the improvement in 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 been conducting research in an attempt to resolve the difficulties of the above-mentioned conventional methods, and in this research, (a) a thermosetting material was We discovered a completely new fact that when a sheet-like material whose main component is resin and each of the constituent layers mentioned above has a specific specific gravity, not only a significantly superior vibration damping effect but also a large sound insulation effect can be obtained at the same time. In addition, (b) it was discovered that when the areal density of each of these constituent layers satisfies a specific relational expression, the damping effect is further improved, and based on these new facts, The present invention has now been completed. That is, the present invention comprises (A) a sheet-like material mainly composed of a bituminous material and having a specific gravity of 1.2 to 1.8, and (B) a resin layer containing a thermosetting resin as a main component and having a specific gravity of 1.2 to 4.5. A multi-layer vibration damping/sound insulating material characterized by the following, and a bituminous sheet side of the damping material placed so as to be in contact with a metal plate,
This invention relates to a vibration damping/sound insulating method characterized in that the vibration damping/sound insulating material is then fused to the metal plate by heating and the thermosetting resin is cured.

In the present invention, by adopting a two-layer structure in which a resin layer mainly composed of a thermosetting resin is formed on one side of a sheet-like material mainly made of bituminous material,
Unlike conventional methods, superior vibration damping effects can be obtained not only in low-temperature ranges but also in high-temperature ranges, and since the thermosetting resin layer has not yet been cured, it can be applied to damped materials with complex shapes, such as automobile bodies. It easily follows the vibration-damped material and has excellent adhesion, and it also has excellent workability because it only needs to be placed in the specified position on the vibration-damped material, completely eliminating all the problems of the conventional method. You can. 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 vibration damping/sound insulating material of the present invention not only employs the above-mentioned two-layer structure, but also limits the specific gravity of each constituent layer to a specific range as described above, thereby achieving an even more excellent vibration damping effect. At the same time, the sound insulation effect is also fully exhibited. In this case, even if a two-layer structure is adopted, if one of the constituent layers falls outside the specific gravity range mentioned above, especially if the specific gravity of the thermosetting resin falls outside of the specific gravity range, the vibration damping effect of the two-layer structure will deteriorate. The vibration damping effect can only be expected by adopting the structure, and the sound insulation effect is hardly achieved.

In addition, in the vibration damping/sound insulating material of the present invention, the areal density of each constituent layer is determined by the following formula: y≧1.70/1.63x+0.6 where x: areal density of the sheet made of bituminous material (Kg/
m ² ) y: By setting the areal density (Kg/m ² ) of the multi-layer vibration damping/sound insulating material to a satisfactory value, the vibration damping effect can be further improved. In other words, by setting such a specific areal density, it is possible to extremely effectively prevent the vibration damping/sound insulating material from blistering, and as a result, the followability and adhesion are improved, and vibration damping/sound insulating materials with complex shapes can be prevented. Not only is the adaptability improved, but as a result of the reduction in bulges, the contact area between the vibration damping/sound insulating material and the damped/sound insulating material increases, and the vibration damping effect is also significantly improved.

In the present invention, each of the constituent layers is defined by two physical properties, specific gravity and areal density, as described above, and the relationship between these can be summarized as follows. It will be done. That is, the areal density of the bituminous material is determined by the damping effect required for the part in which it is used, and the areal density of the epoxy resin layer is determined from the relational expression regarding the areal density. The relationship between the thickness and specific gravity of the sheet is determined by the areal density required for the epoxy resin sheet, but in the present invention, it is preferable to increase the specific gravity and decrease the thickness. The reasons for this can be listed as follows.

(i) The amount of expensive epoxy resin used can be reduced.

(ii) Increasing the specific gravity can be easily achieved by incorporating a large amount of inexpensive filler, and the cost of the epoxy resin composition can be kept low.

(iii) The total thickness of the vibration damping/sound insulating material can be reduced, making it easier to handle, providing excellent followability and adhesion, and improving workability.

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, perlina, and shirasu balloons. Examples of organic fillers include synthetic resins or fibers such as polyethylene, polyamide, and polyester, petroleum resins, synthetic rubber, natural rubber, and wood powder. , rice husk,
Specific examples include linen, wool, etc. 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.

Further, in the present invention, those containing no rubber component at all can also be preferably used. The damping effect can be further improved by using a thermosetting resin layer that does not contain any rubber components and by setting the viscosity of the thermosetting resin layer to 6.0×10 ² to 1.0×10 ⁵ poise (70° C.).

In the present invention, the specific gravity of any product, whether it contains a rubber component or not, is
It is necessary to set the value to 1.2 to 1.8, and if it is outside this range, it is difficult to expect excellent vibration damping and sound insulation effects.

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.

The curing agent is preferably one that exhibits activity in the temperature range of 80 to 200°C at room temperature, such as imidazole derivatives such as dicyandiamide, 4,4'-diaminodiphenylsulfone, 2-n-heptadecyl imidazole, isophthal Acid dihydrazide, N,N-dialkyl urea derivatives, N,N-dialkylthiourea derivatives, etc. 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, the adhesive should be set appropriately depending on the baking conditions so that it hardens and is fixed along the shape and is completely cured, and usually the ratio may be 1 to 20 parts by weight per 100 parts by weight of the epoxy resin.

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, polysulfone, 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 1.0 ^{to 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. Further, the specific gravity of these thermosetting resin layers is 1.2 to 4.5, preferably 1.8 to 4.3. By limiting the specific gravity, particularly excellent vibration damping and sound insulation effects can be obtained.

In the present invention, the workability of the bituminous sheet is improved by forming a thermosetting resin layer on one side of the bituminous sheet in advance, placing it on a metal plate that is the vibration damping material, and then heating it. Desirable from all aspects. Heating has the effect of fusing the bituminous sheet onto the metal plate serving as the damping material and curing the thermosetting resin layer. Particularly in the case of objects to be painted, such as steel plates for automobiles, building materials, and ships, heating during baking in the painting line can be utilized.

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 assembling an automobile body, it is placed at a desired location on a vehicle 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 in tunnels, etc., which get hot during driving or have 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 cured in the painting 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 nitriding liquid, etc., generate gas during heat welding 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 sheet may be made of ordinary 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 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 at this time is usually preferably about 0.01 to 1.8 mm.

EXAMPLES The present invention will be specifically explained 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 bituminous sheet with a thickness of 6.0 mm and an epoxy resin layer with a thickness of 0.5 mm were laminated on a steel plate with a thickness of 0.08 mm and heated at 160°C.
Heating was performed for 30 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
The solid line in the above example 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, and y and x in the above relational expression for areal density are y = 11.2 and x = 9.6, respectively, and this formula is satisfied. It is something.

Example 2 In Example 1 above, the epoxy resin layer and the bituminous layer each had the following compositions (and the areal density of the bituminous sheet was 11.0 Kg/m ² ), and the rest was treated in the same manner as in Example 1. .

<Epoxy resin layer> Epoxy resin 70% Calcium carbonate 20% Iron powder 7% Hardening agent and curing accelerator 3% Specific gravity 1.2 <Bituminous layer> Straight asphalt 50% Talc and calcium carbonate 29% Nylon fiber 3% Petroleum resin 8 % Rubber 5% Asbestos 5% Specific gravity 1.5 In this case, x is 11.0Kg/ ^m2 , and the relational expression for areal density is y=1.70/1.63×11.0+0.6=12.07, which satisfies this equation. . However, the result in this case is
Shown as Figure C.

<Epoxy resin layer> Epoxy resin…24% Barium sulfate and calcium carbonate…13% Iron powder…61% Hardening agent and curing accelerator…2% Specific gravity…3.2 <Bituminous layer> Straight asphalt…47% Talc and calcium carbonate …32% Nylon fiber…5% Petroleum resin…11% Asbestos…5% Specific gravity…1.6 As is clear from Figure 1, when using the method of the present invention, control is almost constant over a wide range from 20°C to 60°C. It exerted a vibration effect and had good sound insulation properties. However, it can be seen that in the case of only a bituminous sheet, the damping effect decreases rapidly as the temperature rises.

Comparative Example 1 In the above Example 1, the bituminous sheet was Example 1.
Leave the epoxy resin layer as is and distribute it as shown below.
The same process was performed by stacking 0.3 mm thick layers and heating them at 160°C for 30 minutes.

<Epoxy resin layer> Epoxy resin…67.5% Calcium carbonate…27% Curing agent and curing accelerator…5.5% Specific gravity…1.1 Relational expression y=9.93 x=9.6 (1.70/1.63×9.6+0.6=10.61) does not satisfy the relational expression.

During the heating process, many bulges occurred between the damping material and the steel plate, and even after cooling, the bulges were fixed by the hardening of the epoxy resin. The adhesion between the vibration damping material and the steel plate was insufficient, resulting in poor vibration damping effects and a tendency for cracks to occur.

Comparative Example 2 Only the specific gravity of the epoxy resin layer in Example 2 was set to 1.1, and the other treatments were the same as in Example 2. However, the formula for areal density in this case is: y is 11.24,
x is 10.2 and satisfies the formula.

The results are shown in FIG. 1A.

Comparative Example 3 The epoxy resin layer of Comparative Example 2 was treated in the same manner as in Comparative Example 2 except that the epoxy resin layer had the following blending ratio and its specific gravity was 4.7.

<Epoxy resin layer> Epoxy resin 20% Calcium carbonate 10% Iron powder 68% Hardening agent and hardening accelerator 3% Specific gravity 4.7 When calculating the formula for areal density in this case, x is 10.1
Then, y=1.043×10.1+0.6=11.13, which satisfied the formula.

The results are shown in FIG. 1B.

Comparative Example 4 Same as Example 2 above, but the areal density is
10.0, y was set to 11.03. In other words, the formula was not satisfied and was made slightly lower. This result is the first
Shown in Figure D.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between temperature and damping effect.

Claims (1)

[Scope of Claims] 1. (A) A resin layer mainly composed of a bituminous material and having a specific gravity of 1.2 to 1.8 on one side, (B) a resin layer containing a thermosetting resin as the main component and having a specific gravity of 1.2 to 4.5. This is a multi-layer vibration damping/sound insulating material, where the areal density of each constituent layer is y≧1.70/1.63x+0.6 x: areal density of bituminous sheet (Kg/m ² ) y: multi-layer vibration damping A vibration damping/sound insulating material that satisfies the following relational expression: areal density of the material (Kg/m ² ). 2. The vibration damping/sound insulating material according to claim 1, wherein the thermosetting resin is an epoxy resin. 3. The vibration damping device according to claim 1 or 2, 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. Sound insulation material. 4. The vibration damping/sound insulating material according to claims 1 and 2, further comprising an outer layer provided on the thermosetting resin layer. 5. Place the multi-layer vibration damping/sound insulating material so that the bituminous sheet side is in contact with the metal plate, then heat to fuse the above vibration damping/sound insulating material to the metal plate and apply thermosetting resin. A vibration damping and sound insulation method that hardens the
The above vibration damping/sound insulating material (A) is mainly made of bituminous material,
A multilayer vibration damping/sound insulating material consisting of (B) a resin layer with a specific gravity of 1.2 to 4.5 mainly composed of a thermosetting resin on one side of a sheet-like material with a specific gravity of 1.2 to 1.8; The areal density satisfies the following relational expression: y≧1.70/1.63x+0.6 x: areal density of bituminous sheet (Kg/m ² ) y: areal density of multilayer damping material (Kg/m ² ) A vibration damping and sound insulation method characterized by: 6. The vibration damping/sound insulating method according to claim 5, wherein the thermosetting resin is an epoxy resin. 7. The vibration damping/sound insulating method according to claim 5 or 6, characterized in that an outer layer is further provided on the thermosetting resin layer. 8. The vibration damping device according to claim 5 or 6, 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. Sound insulation method. 9. The vibration damping/sound insulating method according to claim 5 or 6, wherein the metal plate is a steel plate for automobiles, building materials, or ships, and the heating is performed in a coating line for these.