JPH0776054A - High performance sound insulation material - Google Patents

Abstract

PURPOSE:To provide a high-performance sound insulation material consisting of an acoustic layer and a sound shielding layer. CONSTITUTION:A mixed fiber material 85 consisting of cotton, hemp, polyester fiber 15 and acrylic fiber is mixed with phenol fiber 15 at a ratio of 85wt.% and 15wt.% respectively, then this mixture is processed into a fleece and this fleece is heated to be semicured. Next, this cured product is cut to an appropriate size and is processed into a raw material for an acoustic layer. In addition, the same mixed fiber material is mixed with phenol resin at a ratio of 65wt.% and 35wt.% respectively and the mixture is processed into a fleece. Further, this fleece is heated to be semicured and is cut to an appropriate size to obtain the raw material for the acoustic layer. These raw materials are thermally pressed into a double-tier acoustic layer molded product. Butyl rubber, blown asphalt, calcium carbonate and talc are kneaded and extruded into a molded product with a thickness of 3mm as a sound shielding layer. This sound shielding layer is vacuum-molded. A molded product is deposited on the vacuum- molded product of the sound shielding layer through an adhesive, and is molded under pressure into a high-performance sound insulation material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulating material comprising a sound absorbing layer and a sound insulating layer. More specifically, for example, the sound insulating material is attached to a dash panel that separates a vehicle interior from an engine room,
The present invention relates to a high performance sound insulation material capable of improving the soundproof effect.

[0002]

2. Description of the Related Art Conventionally, for example, as a soundproofing measure, a steel sheet part such as a dash panel, a floor, a trunk room, etc. separating an automobile engine room from a vehicle interior has a sound absorbing material integrated with a vibration damping sheet or a vibration damping sheet. A vibration sheet is applied by itself and is used for soundproofing.

However, under the present circumstances, there is a demand for further improvement in sound insulation, especially when noise caused by the engine of an automobile enters the passenger compartment.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to make it possible to take more sufficient noise countermeasures in all frequency regions.

[0005]

In order to solve such a problem, the inventors of the present invention have as a result of earnest studies, and as a result, among the entire structure of the sound insulating material provided for soundproofing, noise caused by the engine is The present invention has been found that noise in a low frequency region cannot be effectively effectively prevented because the vibration energy passes through a portion and becomes a vibration to affect the sound insulation layer, and the vibration energy reaches the vehicle interior due to the deformation of the sound insulation layer. Therefore, the gist of the present invention lies below.

In a sound insulation material in which a sound absorption layer and a sound insulation layer are integrated, the sound absorption layer is composed of two layers, and the binder component of the sound absorption layer which is in contact with the sound insulation layer among the two sound absorption layers is the binder of the other sound absorption layer. A high-performance sound insulation material characterized by containing less than the components.

The sound-insulating layer in the present invention means rubber such as synthetic rubber, natural rubber and recycled rubber, and binder components such as bituminous material and synthetic resin, calcium carbonate, barium sulfate, talc,
Clay, mica, crushed waste paper, defibrated fiber, glass wool,
Compounding fillers such as plastic balloons, glass balloons, silica balloons, shirasu balloons, hollow carbon spheres,
After the mixture is kneaded by a conventionally known mixing and dispersing machine such as a dissolver, a Banbury mixer, a planetary mixer, an open kneader, a vacuum kneader, etc., a sound insulating sheet having a desired thickness is formed by a rolling machine such as a calendar roll.

The sound absorbing layer in the present invention is made of glass wool, hemp, wool, polyester fiber, nylon fiber, rayon, acrylic fiber, polypropylene fiber, polyethylene fiber, carbon fiber, kinol, or other organic or inorganic type. Natural or synthetic fibers can be used, and recycled fibers obtained by disintegrating clothing, so-called rags, are also preferably used economically. Conventionally known manufacturing methods can be used for these.
That is, a method may be used in which a fibrous raw material is mixed with a thermosetting resin such as a phenol resin or a thermoplastic resin such as polyester or polypropylene to form a fleece, and the fleece is heated to form a semi-cured bulky fabric.

The sound absorbing layer consisting of two layers, which is a feature of the present invention, can be used without restricting the fiber raw material itself of each sound absorbing layer. That is, the same fiber raw material may be used, and of course different fiber raw materials may be used.

In the present invention, it is essential that the mixing amount of the thermosetting resin and the thermoplastic resin to be mixed in forming the fleece from these fiber raw materials be different between the two sound absorbing layers. That is, it is necessary to reduce the binder component of the sound absorbing layer of the sound absorbing layer which is in contact with the sound insulating layer to be smaller than the binder components of the other sound absorbing layers so that the sound absorbing layer has sufficient air fluidity.

In this case, the amount of the binder component mixed in the sound absorbing layer of the sound absorbing layer which is in contact with the sound insulating layer is 1 to 20% by weight, and the amount of the binder component mixed in the other sound absorbing layer is 5 to 40% by weight. Preferably, the air flow resistance of each sound absorbing layer is 0 to 10 dyne · sec / cm ³ and 10 to 5000 dyne · sec / cm ³ after pressure molding.
It is preferable that

That is, when the amount of the binder component mixed in the sound absorbing layer of the sound absorbing layer which is in contact with the sound insulating layer is less than 1% by weight, the sound absorbing layer may be separated from the sound insulating layer. There is a possibility that the desired sound insulation effect may not be realized due to the poor fluidity of air in the material. Further, when the amount of the binder component mixed in the other sound absorbing layer is less than 5% by weight, the sound absorbing layer becomes too soft, and when it exceeds 40% by weight, the sound absorbing layer becomes too hard and the desired sound insulating effect may not be expected. There is. Furthermore,
If the air flow resistance of each sound absorbing layer exceeds 10 dyne · sec / cm ³ after pressure molding in the case of the sound absorbing layer in contact with the sound insulation layer, the fluidity of air may be poor and the expected effect may not be obtained. In the case of other sound absorbing layers, if it is less than 10 dyne · sec / cm ³ , it becomes too soft and if it exceeds 5000 dyne · sec / cm ³ , it becomes too hard and the desired sound insulation effect may not be expected. .

Further, in the present invention, a foam layer of open cells capable of air flow may be provided between the sound absorbing layer and the sound insulating layer. As a method of providing the foam layer, foaming is performed on one surface of the sound absorbing layer or the sound insulating layer. A method of applying, spraying, impregnating, or sticking the agent, foaming in an oven, and then integrating is preferable.

[0014]

EXAMPLES In order to understand the present invention, examples will be described below. Needless to say, the present invention is not limited to the examples below.

[0015]

Example 1 Fleece was prepared by mixing 15% by weight of phenol resin with 85% by weight of mixed fiber raw material consisting of 30% by weight of cotton, 20% by weight of hemp, 30% by weight of polyester fiber and 20% by weight of acrylic fiber. After that, it was heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric 1. The same mixed fiber raw material (65% by weight) was mixed with 35% by weight of a phenol resin to form a fleece, which was then heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer material 2. . The original fabrics 1 and 2 are laminated on a lower mold heated to 200 ° C., the upper mold is lowered, and heat and pressure molding is performed at 100 kg / cm ^{2 for} 1 minute to mold a sound absorbing layer composed of two layers. I created a thing. Kneaded 40 parts by weight of butyl rubber, 5 parts by weight of blown asphalt, 50 parts by weight of calcium carbonate and 5 parts by weight of talc, and 3 mm
It was extruded to a thick thickness to form a sound insulation layer. The sound insulation layer is 100
After preheating at ℃ for 1 minute, it was placed on a lower mold cooled to 5 ℃ and vacuum formed. The molded product of the sound absorbing layer was placed on the vacuum molded product of the sound insulation layer via an adhesive, the upper mold was lowered, and pressure molding was performed at 100 kg / cm ^{2 for} 30 seconds.
A high performance sound insulation material was obtained.

[0016]

Example 2 Fleece was prepared by mixing 10% by weight of phenol resin with 90% by weight of mixed fiber raw material consisting of 30% by weight of cotton, 20% by weight of hemp, 30% by weight of polyester fiber and 20% by weight of acrylic fiber. After that, it was heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric 1. The same mixed fiber raw material of 75% by weight was mixed with 25% by weight of a phenol resin to form a fleece, which was then heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric 2. . The original fabrics 1 and 2 are laminated on a lower mold heated to 200 ° C., the upper mold is lowered, and heat and pressure molding is performed at 100 kg / cm ^{2 for} 1 minute to mold a sound absorbing layer composed of two layers. I created a thing. Kneaded 40 parts by weight of butyl rubber, 5 parts by weight of blown asphalt, 50 parts by weight of calcium carbonate and 5 parts by weight of talc, and 3 mm
It was extruded to a thick thickness to form a sound insulation layer. The sound insulation layer is 100
After preheating at ℃ for 1 minute, it was placed on a lower mold cooled to 5 ℃ and vacuum formed. The molded product of the sound absorbing layer was placed on the vacuum molded product of the sound insulation layer via an adhesive, the upper mold was lowered, and pressure molding was performed at 100 kg / cm ^{2 for} 30 seconds.
A high performance sound insulation material was obtained.

[0017]

Example 3 Fleece was prepared by mixing 5% by weight of phenol resin with 95% by weight of a mixed fiber raw material consisting of 30% by weight of cotton, 20% by weight of hemp, 30% by weight of polyester fiber and 20% by weight of acrylic fiber. After that, it was heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric 1. The same mixed fiber raw material (85% by weight) was mixed with 15% by weight of a phenol resin to form a fleece, which was then heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric (2). . The original fabrics 1 and 2 are laminated on a lower mold heated to 200 ° C., the upper mold is lowered, and heat and pressure molding is performed at 100 kg / cm ^{2 for} 1 minute to mold a sound absorbing layer composed of two layers. I created a thing. Kneaded 40 parts by weight of butyl rubber, 5 parts by weight of blown asphalt, 50 parts by weight of calcium carbonate and 5 parts by weight of talc, and 3 mm
It was extruded to a thick thickness to form a sound insulation layer. The sound insulation layer is 100
After preheating at ℃ for 1 minute, it was placed on a lower mold cooled to 5 ℃ and vacuum formed. The molded product of the sound absorbing layer was placed on the vacuum molded product of the sound insulation layer via an adhesive, the upper mold was lowered, and pressure molding was performed at 100 kg / cm ^{2 for} 30 seconds.
A high performance sound insulation material was obtained.

[0018]

Comparative Example 1 Fleece was prepared by mixing 20% by weight of phenol resin with 80% by weight of a mixed fiber raw material consisting of 30% by weight of cotton, 20% by weight of hemp, 30% by weight of polyester fiber and 20% by weight of acrylic fiber. After that, it was heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric 1. The original fabric 1 is placed on a lower mold heated to 200 ° C. and the upper mold is lowered to 100 kg / cm ²
Was heated and pressed for 1 minute to prepare a raw material. 40 parts by weight of butyl rubber, 5 parts by weight of blown asphalt, 50 parts by weight of calcium carbonate and 5 parts by weight of talc were kneaded and extruded to a thickness of 3 mm to form a sound insulating layer. The sound insulation layer was preheated at 100 ° C. for 1 minute, placed on a lower mold cooled to 5 ° C., and vacuum formed. The above molded product was placed on the vacuum molded product of the sound insulation layer via an adhesive, the upper mold was lowered, and pressure molding was performed at 100 kg / cm ^{2 for} 30 seconds to obtain a high-performance sound insulation material.

[0019]

Comparative Example 2 30% by weight of a phenolic resin is mixed with 70% by weight of a mixed fiber raw material consisting of 30% by weight of cotton, 20% by weight of hemp, 30% by weight of polyester fiber and 20% by weight of acrylic fiber, and a fleece is mixed. After that, it was heated to a semi-cure state and cut into an appropriate size to produce a sound absorbing layer original fabric 1. The original fabric 1 is placed on a lower mold heated to 200 ° C. and the upper mold is lowered to 100 kg / cm ²
Was heated and pressed for 1 minute to prepare a raw material. 40 parts by weight of butyl rubber, 5 parts by weight of blown asphalt, 50 parts by weight of calcium carbonate and 5 parts by weight of talc were kneaded and extruded to a thickness of 3 mm to form a sound insulating layer. The sound insulation layer was preheated at 100 ° C. for 1 minute, placed on a lower mold cooled to 5 ° C., and vacuum formed. The above molded product was placed on the vacuum molded product of the sound insulation layer via an adhesive, the upper mold was lowered, and pressure molding was performed at 100 kg / cm ^{2 for} 30 seconds to obtain a high-performance sound insulation material.

[0020]

[Test method] The soundproofing effect at each frequency of 100 to 5000 Hz was measured. The test method was to vibrate a steel plate with a thickness of 0.8 mm by hitting about 200 metal balls (8 mmφ average), measure the noise level (TL ₀ ) at that time, and perform the same on the steel plate. The noise levels (TL ₁ ) of the soundproofing materials 1 to 6 for vehicle interiors according to the examples and comparative examples were measured. The value of TL ₀ -TL ₁ for each frequency are shown in Table 1 below.

[0021]

[Test Results] The test results are shown in Table 1. The unit in the table is dB
Is. The larger the number, the better the soundproofing effect.

[Table 1]

[0022]

EFFECTS OF THE INVENTION It has been revealed that the high performance sound insulation material of the present invention satisfies the required soundproofing effect in all frequency regions.

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Claims (1)

[Claims] 1. A sound-insulating material in which a sound-absorbing layer and a sound-insulating layer are integrated, wherein the sound-absorbing layer is composed of two layers, and the binder component of the sound-absorbing layer which is in contact with the sound-insulating layer among the two sound-absorbing layers is another sound-absorbing layer. High-performance sound insulation material characterized by containing less than the binder component of.