JP3233307B2 - Sound insulation sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulating sheet having an improved sound damping effect by improving vibration damping properties and reducing radiated sound.

[0002]

2. Description of the Related Art Heretofore, there have been sheet-shaped damping materials obtained by kneading a filler and various additives into rubber, resin, asphalt and the like. Such a vibration damping material is directly or indirectly attached to a vibration generation source, and is used for soundproofing by controlling the vibration. For example, dash panels separating the engine room and the cabin of automobiles, steel plate parts such as floors and trunk rooms, buildings such as music classrooms and floors of apartment houses, air conditioners, compressors, vacuum cleaners and other household appliances that generate noise. As a soundproofing measure, a vibration damping material is used directly, or a material obtained by processing a fiber raw material into a bulky material is formed, or a sound absorbing material such as a molded product of a foam material and a vibration damping sheet are used integrally. .

At present, there is a long-awaited demand for the development of a soundproofing material having a better soundproofing effect due to a demand for further reduction of noise and quietness of a vehicle interior / outside, a building / construction, a home electric appliance and the like. According to the method of increasing the basis weight of the sound absorbing material and forming it bulky in order to achieve such an object, generally, the soundproofing effect is improved, but the soundproofing material is increased in proportion to the improvement of the soundproofing effect. The weight itself increases significantly, which is not preferable from the viewpoint of energy saving, design, economy, and workability.

[0004]

Accordingly, the present invention is to improve the soundproofing effect without increasing the basis weight of the soundproofing material at all or to reduce the weight of the soundproofing sheet itself when the same soundproofing effect is required. The purpose is to reduce it.

[0005]

Means for Solving the Problems In order to solve such problems, the present inventors have made intensive studies and as a result, by forming a sound insulating sheet having a specified elastic modulus at 20 ° C., an excellent sound insulating effect can be realized. That is, the gist of the present invention resides in the following.

[0006] A binder component containing 90% by weight or more of a rubber component, a filler component, additives and the like are kneaded and rolled,
The elastic modulus at 20 ° C. is 5 × 10 ⁷ Pa (Pascal = N /
m ² ) A sound insulating sheet characterized by the following.

Kneading a binder component containing 90% by weight or more of a thermoplastic resin component, a filler component, additives and the like;
A sound insulating sheet which is rolled and has an elastic modulus at 20 ° C. of 5 × 10 ⁷ Pa or less.

A binder component, a filler component and additives containing 90% by weight or more of a rubber component and a thermoplastic resin component are kneaded and rolled, and have an elastic modulus at 20 ° C. of 5 × 10 5
A sound insulating sheet characterized by being ⁷ Pa or less.

The rubber component used in the present invention is a rubber such as a synthetic rubber, a natural rubber, a recycled rubber, etc., specifically, butyl rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, ethylene propylene rubber, chloroprene rubber, acrylic rubber. , Acrylonitrile butadiene rubber or the like can be exemplified alone or in combination. As the thermoplastic resin component, polyester, polypropylene, EVA, SIS,
The use of SBS, EPDM, etc. can be illustrated,
It is essential that the elastic modulus at 5 ° C. is 5 × 10 ⁷ Pa or less. Further, it is essential that the rubber component or the thermoplastic resin component contains 90% by weight or more of the binder component. If the content is less than 90% by weight, the desired soundproof effect cannot be exhibited.

In the present invention, a rubber component and a thermoplastic resin component may be used at the same time. In this case, the elasticity of the sound insulating sheet using the rubber and the thermoplastic resin as a binder component is 5 × 10 ⁷ Pa or less. It is essential that the total amount includes 90% by weight or more of the binder component. By satisfying such conditions, it is possible to find excellent soundproofing performance of the soundproof sheet.

As the other binder component, asphalt may be used, and straight asphalt, blown asphalt, rubber-modified asphalt, or asphalt obtained by mixing these may be used.

The filler used in the present invention is a filler such as calcium carbonate, barium sulfate, talc, clay, etc., a flaky filler such as mica, a crushed waste paper, a defibrated fiber, a fibrous filler such as glass wool. And hollow fillers such as plastic balloons, glass balloons, silica balloons, shirasu balloons and carbon hollow spheres.

Further, if necessary, additives may be added to the total amount of 1%.
0% by weight or less can be added. As an additive, a moisture absorbent such as quicklime or silica gel, an antistatic agent, a pigment dispersant, an antioxidant, and the like may be blended.

In order to produce the sound insulating sheet according to the present invention, the above-mentioned various compounds are dispersed and kneaded by a conventionally known mixing and dispersing machine such as a dissolver, a Banbury mixer, a planetary mixer, an open kneader, and a vacuum kneader. And a rolling machine such as a calender roll to form a sound insulating sheet having a desired thickness. The obtained sheet is trimmed according to the surface shape of a desired portion. If necessary, an adhesive such as a pressure-sensitive adhesive may be applied to the back surface of the sound-insulating sheet and a release paper may be adhered to the sound-insulating sheet.

[0015] The thus obtained sound insulating sheet 2
The elastic modulus at 0 ° C. must be 5 × 10 ⁷ Pa or less. With respect to the sound insulating sheet according to the present invention, the sound insulating property is such that the elastic modulus of the material contributes and the elastic modulus is lower,
Sound emitted from the sound insulating sheet by absorbing vibration is reduced. This is because the effect is remarkably exhibited when the elastic modulus is 5 × 10 ⁷ Pa or less. Therefore, if the elastic modulus exceeds 5 × 10 ⁷ Pa, satisfactory sound insulation cannot be obtained.

[0016]

EXAMPLES In order to facilitate understanding of the present invention, examples will be described below. Needless to say, the present invention is not limited to the following examples.

[0017]

Example 1 5 parts by weight of mica and 60 parts by weight of calcium carbonate were kneaded with a binder component consisting of 25 parts by weight of butyl rubber and 2 parts by weight of oil, and extruded to a thickness of 3 mm to form a sound insulating sheet 1. The elastic modulus of the sound insulating sheet is 2 ×
Was 10 ⁷ Pa.

[0018]

Example 2 25 parts by weight of polypropylene resin, oil 2
5 parts by weight of mica and 60 parts by weight of calcium carbonate were kneaded with a binder component consisting of parts by weight, and extruded to a thickness of 3 mm to form a sound insulating sheet 2. The elastic modulus of the sound insulating sheet was 3 × 10 ⁷ Pa.

[0019]

Example 3 EPDM 10 parts by weight, isoprene rubber 12
5 parts by weight of mica and 65 parts by weight of calcium carbonate were kneaded with a binder component consisting of 2 parts by weight of asphalt and 2 parts by weight of oil, and extruded to a thickness of 3 mm to form a sound insulating sheet 3. The elastic modulus of the sound insulating sheet is 4 × 10
⁷ Pa.

[0020]

Comparative Example 1 A binder component consisting of 10 parts by weight of EVA, 5 parts by weight of natural rubber, 10 parts by weight of asphalt, and 2 parts by weight of oil was kneaded with 5 parts by weight of mica and 70 parts by weight of calcium carbonate, and extruded to a thickness of 3 mm. , Sound insulation sheet 4
And The elastic modulus of the sound insulating sheet was 1 × 10 ⁸ Pa.

[0021]

Comparative Example 2 5 parts by weight of mica and 75 parts by weight of calcium carbonate were kneaded with a binder component consisting of 5 parts by weight of a polypropylene resin, 5 parts by weight of SBR, 15 parts by weight of asphalt, and 2 parts by weight of oil, and extruded to a thickness of 3 mm. And a sound insulating sheet 5. The elastic modulus of the sound insulating sheet is 5 × 10
⁸ Pa.

[0022]

[Test method] The soundproofing effect at each frequency of 100 to 5000 Hz was measured. The test method was as follows: a steel sheet having a thickness of 0.8 mm was vibrated by hitting about 200 metal balls (8 mmφ average), and the noise level (TL ₀ ) at that time was measured. The sound insulating sheets 1 to 5 as comparative examples were integrated, and the noise level (TL ₁ ) was measured. Table 1 below shows the value of TL ₀ −TL ₁ for each frequency.
It was shown to.

[0023]

[Results] Table 1 shows the test results. The unit in the table is dB. The higher the number, the higher the soundproofing effect.

[Table 1]

[0024]

It has been found that the sound insulating sheet according to the present invention satisfies the required sound insulating effect in all frequency ranges.

Continuation of the front page (56) References JP-A-3-175022 (JP, A) JP-A-4-89863 (JP, A) US Patent 5000483 (US, A) (58) Fields investigated (Int. ⁷ , DB name) C08L 21/00 C08K 3/00 G10K 11/162

Claims (3)

(57) [Claims] 1. A binder component containing 90% by weight or more of a rubber component, a filler component, additives and the like are kneaded and rolled, and have an elastic modulus at 20 ° C. of 5 × 10 ⁷ Pa (Pascal =
N / m ² ) or less. 2. A binder component, a filler component and additives containing 90% by weight or more of a thermoplastic resin component are kneaded and rolled to have an elastic modulus at 20 ° C. of 5 × 10 ⁷ Pa or less. Sound insulation sheet. 3. A binder component containing 90% by weight or more of a rubber component and a thermoplastic resin component, a filler component, additives and the like are kneaded and rolled, and have an elastic modulus at 20 ° C. of 5 × 1.
A sound insulating sheet characterized by being not more than 0 ⁷ Pa.