JP2001303691A - Vibration-damping sound insulating material and floor structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide vibration-damping sound insulating materials capable of delivering excellent vibration-damping sound insulating performance, having favorable handleability and constructibility owing to lightness in weight, and a floor structure having the above performance and using the above materials. SOLUTION: The vibration-damping sound insulating materials are the one having specific gravities of 1.5 to 2.4d individual-material sonic velocities of 50 to 200 m/s, the one mainly composed of a butyl rubber, and the one wherein 80-400 pts.wt. inorganic filler is added for kneading to 100 pts.wt. rubber or synthetic resin. In the floor structure, the rear surface of a floor surface material and any one of the above materials are bonded together for lamination through the medium of an elastic adhesive, and Young's modulus of the cured elastic adhesive is 0.5 to 10 MPa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration-damping and sound-insulating material and a floor structure using the vibration-damping and sound-insulating material.

[0002]

2. Description of the Related Art In recent years, with the increase in the number of multi-family houses and the increase in the use of floor surface materials such as light wooden floors such as wooden floors, floors for lower floors in apartment buildings and general detached houses have been developed. There is a strong demand to prevent noise. In response to such demands, in order to prevent floor noise such as the impact noise of wooden lightweight floors, a vibration damping material (a vibration damping material) must be installed between the floor below the upper floor and the ceiling below. Include)
It is widely used to intervene.

[0003] The most commonly used as the vibration damping material is an asphalt vibration damping material obtained by kneading asphalt and an inorganic aggregate and having a specific gravity of 2.5 or more. Japanese Patent Publication No. Hei 4-65777 discloses a vibration damper characterized in that a converter blast slag, asphalt or rubber asphalt and an additive are kneaded and formed into a plate shape, and a fiber such as a nonwoven fabric is adhered to the surface thereof. A sound insulation sheet (vibration suppression sound insulation material) "is disclosed.

However, the above-mentioned asphalt-based vibration damping material has asphalt or rubber asphalt as a main component, and is kneaded with inorganic aggregate such as converter blast slag, so that the specific gravity is 2.5 or more. In a detached house or the like, there is a problem that the load on the second floor or the third floor, the burden on the operator when handling it at the site increases, and the workability (workability) deteriorates.

On the other hand, Japanese Unexamined Patent Publication No. 6-301386 discloses a vibration damping and sound insulating material having a relatively low specific gravity, which states that "a binder component containing 90% by weight or more of a rubber component, a filler, an additive, and the like are kneaded and rolled. A sound-insulating sheet (vibration-damping material) characterized in that the sheet-shaped sound-insulating sheet contains 10% by weight or more of a rubber component having a loss coefficient of 0.5 or more at 20 ° C.

[0006] However, the vibration damping and sound insulating material disclosed in the above disclosure is relatively light in weight and light in weight, but cannot provide sufficient vibration damping and sound insulating performance because the sound damping and sound insulating performance essentially depends on the surface density. There is a problem.

[0007]

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a vibration-damping and sound-insulating material which is light in weight, has good handleability and workability, and can exhibit excellent vibration-damping and sound-insulating performance. Another object of the present invention is to provide a floor structure having excellent vibration damping and sound insulating performance using the vibration damping and sound insulating material.

[0008]

The vibration damping and sound-insulating material according to the first aspect of the present invention (hereinafter referred to as "the present invention 1") has a specific gravity of 1.5 to 2.4 and a material individual sound velocity of 1.5 to 2.4. 50-20
0 m / sec.

A vibration-damping and sound-insulating material according to the second aspect of the present invention (hereinafter referred to as "the present invention 2") is characterized in that the main component is butyl rubber in the vibration-damping and sound-insulating material according to the first present invention. .

The vibration damping and insulating material according to the third aspect of the present invention (hereinafter referred to as “the present invention 3”) is the same as the vibration damping and sound insulating material according to the first aspect of the present invention, based on 100 parts by weight of rubber or synthetic resin. It is characterized in that 80 to 400 parts by weight of an inorganic filler is added and kneaded.

Further, the floor structure according to the invention of claim 4 (hereinafter referred to as “the present invention 4”) is provided with the back surface of the floor surface material and the floor structure according to any one of the present invention 1 to the present invention 3 described above. A floor structure in which a vibration-insulating material is bonded and laminated via an elastic adhesive, wherein a cured product of the elastic adhesive has a Young's modulus of 0.1.
The pressure is 5 to 10 MPa.

The vibration-damping and sound-insulating material of the present invention 1 has a specific gravity of 1.
It needs to be 5 to 2.4. Here, the specific gravity means a density measured according to JIS Z 8807.

If the specific gravity of the vibration-damping and sound-insulating material is less than 1.5, the weight of the vibration-damping and sound-insulating material becomes too light to stop the vibration of the floor surface material and the floor structure. The density becomes low, and the vibration damping and sound insulating performance becomes insufficient. Conversely, when the above specific gravity of the vibration damping and sound insulating material exceeds 2.4, the weight of the vibration damping and sound insulating material becomes too heavy, and the handling and construction properties are impaired, and the burden on the operator increases.

Further, the vibration damping and sound insulating material according to the first aspect of the present invention needs to have a sound velocity of 50 to 200 m / sec. Here, the sound velocity of the individual material means the sound velocity of the individual material obtained by the following equation (1). C = (E / ρ) ^1/2 Equation (1) where C represents the sound velocity of the material (m / sec), E represents the Young's modulus (Pa), and ρ represents the density (kg / m ³ )}.

[0015] The Young's modulus referred to herein is JIS K
It means the tensile modulus measured according to 7113 (Plastic tensile test method).

The sound velocity of the material of the vibration-damping and sound-insulating material is 50 m /
If it is less than seconds, the surface of the floor surface material will be uneven when nailing is performed at the time of floor construction, or the floor structure will be deformed such as dents when furniture or the like is placed for a long time. Conversely, if the material sound velocity of the vibration-damping and sound-insulating material exceeds 200 m / sec, vibration is likely to be transmitted over time, and the vibration-damping and sound-insulating performance is reduced.

The material sound velocity of the vibration damping and sound insulating material is 50 to 200.
As is apparent from the above equation (1), when the material individual sound velocity of the vibration damping and sound insulating material is less than 50 m / sec, the Young's modulus What is necessary is just to raise (E) or lower the density (ρ). In order to increase the Young's modulus (E) of the vibration-damping and sound-insulating material, the Young's modulus of rubber or synthetic resin itself used as a main component of the vibration-damping and sound-insulating material may be increased, or the amount of the inorganic filler added may be increased. . On the other hand, when the sound velocity of the material of the vibration damping and sound insulating material is 200
If it exceeds m / sec, the Young's modulus (E) of the vibration damping and sound insulating material may be reduced or the density (ρ) may be increased. In order to lower the Young's modulus (E) of the vibration-damping and sound-insulating material, the Young's modulus of rubber or synthetic resin itself used as a main component of the vibration-damping and sound-insulating material may be reduced, or the amount of the inorganic filler added may be reduced. .

The individual sound speed of the vibration damping and sound insulating material is 50 to 200.
In order to fall within the range of m / sec, the Young's modulus of the rubber or synthetic resin itself used as the main component is 1 to 50M.
Although it is preferably Pa, the material individual sound velocity of the vibration damping and sound insulating material also varies depending on the kind and amount of the inorganic filler to be added or the affinity or kneading property of the inorganic filler with rubber or synthetic resin. However, the present invention is not limited to the above range of Young's modulus.

Next, the vibration-damping and sound-insulating material of the second aspect of the present invention requires that the main component of the vibration-damping and sound-insulating material of the first aspect of the present invention be butyl rubber. Here, the main component means a rubber or a synthetic resin constituting the vibration damping and sound insulating material.

In the vibration-damping and sound-insulating material of the present invention 2, the butyl rubber may be used alone as a main component of the vibration-damping and sound-insulating material, or may be used in combination with a rubber or a synthetic resin other than butyl rubber described later. It may be used as a main component of the vibration damping and sound insulating material.

[0021] The content of butyl rubber in the main component of the vibration-damping and sound-insulating material of the second invention is not particularly limited, but is preferably 60% by weight or more. When the content of butyl rubber in the main component is less than 60% by weight, the loss coefficient of the vibration damping and sound insulating material becomes too low, and the elastic modulus becomes too high. In some cases, the adhesion performance of the vibration damping and sound insulating material to the back surface of the floor surface material may be low, and the vibration damping and sound insulating material may have insufficient vibration damping and sound insulating performance.

Next, the vibration-damping and sound-insulating material of the present invention 3 is the same as the vibration-damping and sound-insulating material of the present invention 1 described above, except that the rubber or synthetic resin 1 is used.
It is necessary that 80 to 400 parts by weight of the inorganic filler is added and kneaded with respect to 00 parts by weight.

The rubber which may be used as a main component of the vibration damping and sound insulating material of the present invention 3 includes, for example, natural rubber (N
R), styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene copolymer rubber (NBR), chloroprene rubber (CR), butyl rubber (IIR), polybutadiene rubber (BR), polyisoprene rubber (I
R), ethylene-propylene copolymer rubber (EPR), ethylene-propylene-diene terpolymer rubber (EPD)
M) and the like; special rubbers such as silicone rubber, fluorine rubber, acrylic rubber, ethylene-acryl copolymer rubber, hydrin rubber and propylene oxide rubber; and reclaimed rubbers of the above-mentioned general rubbers and special rubbers. These rubbers may be used alone or in combination of two or more.

Examples of the synthetic resin which may be used as a main component of the vibration damping and sound insulating material of the present invention 3 include vinyl chloride resins such as vinyl chloride resin, vinyl chloride-vinyl acetate copolymer resin, and vinylidene chloride resin. Resin; Polyolefin resin such as polyethylene resin and polypropylene resin; halogenated polyolefin resin such as chlorosulfonated polyethylene resin, chlorinated polyethylene resin, chlorinated polypropylene resin; acrylic resin; polyester resin;
Polyamide-based resins and the like are listed. These synthetic resins may be used alone or in combination of two or more.

The above rubber or synthetic resin may be used alone or in combination.

Examples of the inorganic filler that may be added to the vibration damping material of the present invention 3 include iron sand, iron powder, iron oxide, calcium carbonate, zircon sand, chromite sand, iron slag powder, silica sand, and lead powder. , Tin oxide, zinc oxide, barium sulfate, iron sulfide, mica, aluminum hydroxide, talc,
Clay and the like can be mentioned. Among them, calcium carbonate and barium sulfate, which are advantageous in terms of affinity with the rubber or the synthetic resin, kneadability, uniform dispersibility, productivity, cost, and the like, are preferably used. These inorganic fillers may be used alone or in combination of two or more.

The shape of the above-mentioned inorganic filler is not particularly limited, and may be, for example, any of powder, fiber, flake, and the like.

The inorganic filler is not particularly limited, but preferably has an average particle diameter of 1 mm or less, more preferably 1 to 100 μm.
When the average particle diameter of the inorganic filler exceeds 1 mm, it becomes difficult to uniformly knead the rubber or the synthetic resin,
The damping and sound insulating performance of the damping material may be impaired.

In the vibration damping and sound-insulating material according to the third aspect of the present invention, it is necessary that 80 to 400 parts by weight of the inorganic filler is added to and kneaded with 100 parts by weight of the rubber or synthetic resin used as a main component. It is.

If the amount of the inorganic filler is less than 80 parts by weight per 100 parts by weight of the rubber or the synthetic resin, the specific gravity of the vibration damping and sound insulating material becomes less than 1.5 or the sound velocity of the material becomes 5%.
When it is less than 0 m / sec, the vibration damping and sound insulating performance of the vibration damping and sound insulating material becomes insufficient. Conversely, when the amount of the inorganic filler added to 100 parts by weight of the rubber or the synthetic resin exceeds 400 parts by weight, the specific gravity of the vibration damping and sound insulating material exceeds 2.4, and the handleability and workability deteriorates, And the sound speed of the individual material exceeds 200 m / sec, and the vibration damping and sound insulating performance of the vibration damping and sound insulating material becomes insufficient.

The vibration damping and sound insulating material of the present invention (the present invention 1 to the present invention 3
In addition to rubber or synthetic resin and inorganic filler, other than rubber or synthetic resin and inorganic filler, a softener, a plasticizer, or a thickener for adjusting viscosity may be used as long as the object of the present invention is not hindered. Various additives such as gelling agents, lubricants, fluidity-imparting agents, surfactants, coupling agents, pigments, antioxidants (antiaging agents), heat stabilizers, light stabilizers, antistatic agents, flame retardants, etc. 1
Seeds or two or more kinds may be added and kneaded.

The vibration damping and sound insulating material of the present invention is not particularly limited, but preferably has a sheet shape.

As a method for producing the sheet-shaped vibration-damping and sound-insulating material, for example, a predetermined amount of rubber or synthetic resin as a main component, a predetermined amount of inorganic filler, and various additives to be added as necessary are used. For example, a method of supplying a rubber or a synthetic resin composition consisting of a predetermined amount of two or more kinds to an extruder, uniformly melt-kneading, and extruding while shaping into a sheet, or a usual stirring kneader. After the above-mentioned rubber or synthetic resin composition is uniformly melt-kneaded, for example, a hot press method of shaping the sheet into a sheet shape by a hot press and the like can be mentioned.

The sheet-shaped vibration damping material thus obtained is
Although not particularly limited, the thickness is 2 to 12 m
m is preferable. If the thickness of the sheet-shaped vibration-damping material is less than 2 mm, the thickness may be insufficient and the vibration-damping and sound-insulating material may be inadequate. May become heavy, handling and construction properties may be impaired, and the burden on workers may increase.

On one or both surfaces of the sheet-shaped vibration damping material, for example, paper, woven fabric, etc. may be used, if necessary, in order to improve the handleability and workability as long as the object of the present invention is not hindered. Various surface materials such as cloth, nonwoven fabric, synthetic resin film or sheet, glass cloth, and metal foil may be laminated.

Next, the floor structure of the fourth aspect of the present invention is a floor structure in which the back surface of the floor surface material and the above-described vibration damping and sound insulating material of the present invention are bonded and laminated via an elastic adhesive. The cured product of the elastic adhesive needs to have a Young's modulus of 0.5 to 10 MPa.

The floor surface material used in the floor structure of the present invention 4 includes, for example, various floor surface materials generally used such as woody or non-woody flooring materials, tiles, floorboards, decorative boards and the like. Is mentioned. These floor coverings are
They may be used alone or in combination of two or more.

The elastic adhesive used for bonding the back surface of the floor surface material and the vibration damping and sound insulating material of the present invention has a cured product (including a dried product) having a Young's modulus of 0.5, which will be described later. Any adhesive may be used as long as it can be in the range of 10 MPa to 10 MPa. For example, a rubber-based adhesive containing natural rubber or synthetic rubber as a main component; styrene-butadiene block copolymer or styrene-isoprene block Thermoplastic elastomer adhesives containing copolymers and hydrogenated products thereof as main components; acrylic resins, urethane resins, silicone resins, modified silicone resins,
Synthetic resin adhesives containing epoxy resin, polysulfide resin or the like as a main component are exemplified. These elastic adhesives may be used alone or in combination of two or more.

The form of the elastic adhesive is not particularly limited, and may be a solvent-type adhesive, an emulsion-type adhesive, a hot-melt-type adhesive, a one-part moisture-curable adhesive, or a two-part adhesive. And any of a reactive adhesive, a photopolymerizable adhesive, a film-like or sheet-like adhesive, and the like.

Among the above various elastic adhesives, one-part urethane-based moisture-curable adhesives are excellent in terms of adhesion, cohesion, elasticity, handleability, workability, and safety of the cured product. A one-part, modified silicone-based moisture-curable adhesive is particularly preferably used.

In the present invention 4, it is necessary that the cured product of the elastic adhesive has a Young's modulus of 0.5 to 10 MPa. In addition, the Young's modulus mentioned here is JIS K7
113 (Tensile test method for plastics).

The cured product of the elastic adhesive has a Young's modulus of 0.
When the pressure is less than 5 MPa, the vibration of the floor surface material cannot be sufficiently suppressed, so that the vibration damping and sound insulating performance of the floor structure becomes insufficient, and conversely, the Young's modulus of the cured product of the elastic adhesive becomes 1
If it exceeds 0 MPa, the impact to the floor surface material cannot be sufficiently buffered, and the floor structure has insufficient vibration damping and sound insulating performance.

As a method of constructing a floor surface material on a floor base material using the vibration damping and sound insulating material of the present invention, for example, first, one surface of the vibration damping and sound insulating material is laminated on the floor base material and then laminated. After applying the above-mentioned elastic adhesive to one or both of the other surface of the vibration-damping and sound-insulating material and the back surface of the floor surface material, and performing drying and heating if necessary, on the other surface of the vibration-damping and sound-insulating material, A method in which the back surfaces of the floor structures are overlapped and both are adhered and laminated,
By adopting such a construction method, it is possible to obtain a floor structure exhibiting excellent vibration damping and sound insulating performance.

Examples of the floor substrate include various floor substrates commonly used, such as plywood, particle board, OSB board, and MFD board. These flooring materials may be used alone or in combination of two or more.

As a method of laminating the vibration damping and sound insulating material on the floor base material, for example, a method of bonding and fixing both using the elastic adhesive or a normal adhesive other than the elastic adhesive,
A method of fixing both using a nail such as a tucker, or
A method of using an adhesive and a nail in combination to fix the two together, and the like, may be used, and any lamination method may be adopted.

[0046]

The specific gravity of the vibration damping and sound insulating material of the present invention is 1.5 to 2.4.
, Light weight, good handleability and workability, and light burden on the operator. Further, since the vibration damping and sound insulating material of the present invention has a sound velocity of the individual material in the range of 50 to 200 m / sec, the propagation speed of the vibration is slow, and the material is excellent despite its light weight (low specific gravity). It can exhibit vibration damping and sound insulation performance.

In the vibration damping and sound-insulating material of the present invention, butyl rubber is used as a main component, or a specific amount of an inorganic filler is added to and kneaded with a specific amount of a rubber or a synthetic resin as a main component. Thereby, the vibration damping and sound insulating performance becomes more excellent.

In the floor structure of the present invention, the back surface of the floor surface material and the above-mentioned vibration damping and sound insulating material of the present invention are bonded and laminated via an elastic adhesive whose Young's modulus of the cured product is in a specific range. Excellent vibration and sound insulation performance.

[0049]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means “parts by weight”.

(Example 1)

(1) Production of vibration-damping and sound-insulating material A rubber composition comprising 85 parts of butyl rubber, 15 parts of polyethylene resin and 300 parts of calcium carbonate was extruded into a sheet to produce a sheet-shaped vibration-damping and sound-insulating material having a thickness of 4 mm. did. The specific gravity and the material sound velocity of the obtained sheet-shaped vibration damping material were measured and calculated by the above-described method. The results were as shown in Table 1.

(2) Construction of Floor Structure The sheet-like vibration damping material obtained above is placed on a particle board as a floor base material, and denatured silicone is formed on the sheet-like vibration damping material as an elastic adhesive. A wooden flooring material (thickness: 12 mm) as a floor surface material applied to the back surface of a wooden adhesive (trade name “Esdine # 75”, manufactured by Sekisui Chemical Co., Ltd.) was superposed and adhered to construct a floor structure. . The Young's modulus of the cured product of the elastic adhesive (modified silicone adhesive) “ESDINE # 75” used above was measured by the above method. The results were as shown in Table 1.

(3) Evaluation The workability of the sheet-shaped vibration-damping material obtained above and the vibration-damping and sound-insulating performance of the floor structure obtained above were evaluated using a wooden frame two-story building (the first floor and the second floor). Approximately 13 m ² ) In the evaluation building, the evaluation was performed by the following method. The results were as shown in Table 1.

Workability: The sheet-shaped vibration-damping material is carried from the first floor to the second floor, and laid on the floor base material of the entire room on the second floor.
The time required to complete the installation (time to install the sheet-shaped vibration-damping material) was measured. When the sheet-shaped vibration damping material is laid, the sheet-shaped vibration damping material should be installed in accordance with the room.
After cutting to a 10 mm square with a cutter, it was laid on a floor base material. In addition, no bonding or fixing was performed between the floor base material and the sheet-shaped vibration damping material. The shorter the sheet-like vibration damping material laying time, the better the workability.

Vibration control and sound insulation performance: The impact sound of the floor structure was measured in accordance with JIS A-1418, and the frequency was 125H.
z, noise level at 250 Hz and 500 Hz (d
B) was determined. The smaller the noise level (dB) is, the better the vibration suppression and sound insulation performance is.

Example 2 In the production of the vibration damping and sound insulating material,
A sheet-like vibration damping material and a floor structure were obtained in the same manner as in Example 1 except that a rubber composition comprising 100 parts of butyl rubber and 200 parts of calcium carbonate was used.

Example 3 In the production of a vibration damping and sound insulating material,
A sheet-shaped vibration damping material and a floor structure were obtained in the same manner as in Example 1 except that a rubber composition comprising 90 parts of butyl rubber, 10 parts of polyethylene resin and 200 parts of barium sulfate was used.

(Comparative Example 1) In the production of the vibration damping and sound insulating material,
A sheet-shaped vibration damping material and a floor structure were obtained in the same manner as in Example 1 except that an asphalt composition comprising 80 parts of straight asphalt and 300 parts of iron oxide was used.

(Comparative Example 2) In the production of the vibration damping sound insulating material,
A sheet-shaped vibration-damping material and a floor structure were obtained in the same manner as in Example 1 except that a rubber composition comprising 100 parts of butyl rubber and 50 parts of calcium carbonate was used.

(Comparative Example 3) In the production of a vibration damping sound insulating material,
100 parts of polybutadiene rubber and 300 calcium carbonate
A sheet-shaped vibration-damping material and a floor structure were obtained in the same manner as in Example 1 except for using the rubber composition composed of a rubber part.

Examples 2 and 3, and Comparative Examples 1 to
The specific gravity and sound velocity of the material of the sheet-shaped vibration damping material obtained in Comparative Example 3 were measured in the same manner as in Example 1.
The results were as shown in Table 1.

Further, the workability of the sheet-shaped vibration-damping and sound-insulating materials obtained in Examples 2 and 3, and Comparative Examples 1 to 3 was evaluated in the same manner as in Example 1. Furthermore, the vibration-damping and sound-insulating performances of the floor structures obtained in Examples 2 and 3, and Comparative Examples 1 to 3 were evaluated in the same manner as in Example 1. The results were as shown in Table 1.

[0063]

[Table 1]

As is clear from Table 1, the damping time of each of the vibration damping and sound insulating materials of Examples 1 to 3 according to the present invention was short. This indicates that the workability was good. Further, the floor structures of Examples 1 to 3 according to the present invention constructed using the vibration damping and sound insulating materials had low noise levels at frequencies of 125 to 500 Hz.
This indicates that excellent vibration damping and sound insulating performance has been achieved.

On the other hand, the vibration damping and sound insulating material of Comparative Example 1, which was mainly composed of straight asphalt, had a specific gravity of more than 2.4, and the sound velocity of the individual material exceeded 200 m / sec, had a laying time of It was long. This indicates that the workability was poor. In addition, the floor structure of Comparative Example 1 constructed using this vibration damping and sound insulating material was slightly inferior in vibration damping and sound insulating performance.

Comparative Example 2 in which the specific gravity was less than 1.5
The floor structure of Comparative Example 2 constructed using the vibration damping sound insulating material of Comparative Example 3 and the floor structure of Comparative Example 3 constructed using the vibration damping sound insulating material of Comparative Example 3 in which the material individual sound speed exceeded 200 m / sec was In each case, the workability was good, but the vibration damping and sound insulating performance was poor.

[0067]

As described above, the vibration-damping and sound-insulating material of the present invention is lightweight, has good handleability and workability, reduces the burden on workers, and exhibits excellent vibration-damping and sound-insulating performance. Therefore, it is suitably used as a vibration-damping and sound-insulating material for floor noise prevention in apartment houses and detached houses.

Further, the floor structure of the present invention constructed using the above-described vibration damping and sound insulating material exhibits excellent vibration damping and sound insulating performance, and is therefore suitable as a floor structure for a multi-family house or a detached house. is there.

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Claims (4)

[Claims] 1. A vibration damping and sound insulating material having a specific gravity of 1.5 to 2.4 and a material sound velocity of 50 to 200 m / sec. 2. The vibration-damping and sound-insulating material according to claim 1, wherein the main component is butyl rubber. 3. The vibration damping and sound insulating material according to claim 1, wherein 80 to 400 parts by weight of an inorganic filler is added to and kneaded with 100 parts by weight of rubber or synthetic resin. 4. A floor structure comprising a back surface of a floor surface material and the vibration-damping and sound-insulating material according to any one of claims 1 to 3 bonded and laminated via an elastic adhesive, A floor structure, wherein the cured product of the elastic adhesive has a Young's modulus of 0.5 to 10 MPa.