JPH08333820A - Sound absorbing material - Google Patents

Abstract

PURPOSE: To enhance sound absorbing properties in a wide frequency range by pasting a plurality of corrugated boxlike members where a film or a sheet is pasted with a folded film or sheet. CONSTITUTION: A corrugated board 8 where a film or a sheet is pasted with a corrugated or folded film or sheet, is pasted in the form of a valley with a binding material so that through holes may be faced upward, thereby forming a sound absorbing material. A sheet-like member having a large number of independent foams where a film or a sheet having a large number of projected parts is pasted with each other on one surface, are placed one upon another, thereby forming the other sound absorbing material. A sheet-like member where a band-like member made of rubber or the like is pasted with a spacing, is placed one upon another, for example, thereby forming the other sound absorbing material. A member which bundles a large number of straw member having a through hole or connects the straw member in the form of a flat surface, are placed one upon the other, thereby forming the other sound absorbing material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound absorbing material, and more particularly to a sound absorbing material having excellent characteristics in a wide frequency range.

In recent years, quiet environments have been demanded in various fields such as life and industry. For example, in the field of living, quiet houses have been used, and in the field of industry, the focus has been to prevent noise outside the factory. A good environment for people has come to be pursued. For this reason, various demands regarding the prevention of sound and vibration have become apparent, and as measures against this, a combination of means such as sound insulation, sound absorption, vibration control, and vibration control has been performed.

[0003]

2. Description of the Related Art Conventionally, as materials for sound absorbing materials, inorganic fibers, organic fibers, open-cell foams, aluminum foams, porous materials and the like have been used. Among them, glass wool and rock wool are mainly used from the viewpoint of cost and flame retardancy. However, glass wool and rock wool have a drawback in sound absorption characteristics that they are effective for high-frequency sounds, but are not effective for low-frequency sounds at normal use thickness. Also, for workers,
These short fibers cause problems such as itching due to skin irritation and adverse effects on the respiratory system, which makes it difficult to use in terms of occupational safety and health.

On the other hand, since a polymer material such as urethane having an open cell structure is a foam, the thickness of the film itself becomes thin and it is liable to be deteriorated by hydrolysis or oxidation, and cannot be used for a long time. It has drawbacks. In addition, aluminum foam has a problem of high cost. From the above viewpoint, it is desired to develop a sound absorbing material that has stable performance over a wide frequency range for a long period of time.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide at low cost a sound absorbing material which has no drawbacks in occupational safety and health, is effective in a wide frequency range, and can exhibit its performance over a long period of time.

The sound-absorbing material according to the present invention is a sound-absorbing material (A) formed by bonding a plurality of corrugated members formed by bonding at least one film or sheet and a corrugated or folded plate-shaped film or sheet to each other. Alternatively, a sound absorbing material formed by stacking or winding a sheet-like member having a large number of closed cells, which is obtained by sticking a sheet and a film or sheet having a large number of convex portions formed on one surface thereof.
(B), sound absorbing material (C), through-holes formed by stacking or winding sheet-like members in which strip-shaped members made of rubber or foam are attached at arbitrary intervals on one surface of the film or sheet Part of the sound absorbing material (D) and the straw-shaped member formed by stacking or winding the straw-shaped members having a plurality of straw-shaped members or connecting them in a flat shape, and bending the bellows portion Forming one or more sound absorbing materials selected from sound absorbing materials (E) formed by bundling or connecting a number of members with a long sound propagation path length by themselves, or by stacking or winding them. It is characterized by.

[0007]

The sound absorbing material according to the present invention has a large number of through holes or openings, and the through holes or openings are installed so as to face the sound source side, and the air flow when the air passes through the inside is received. A sound absorbing effect is brought about by attenuating sound waves by converting acoustic energy into heat energy by resistance.

In the present invention, a material having a through hole or opening is used, and a sound absorbing effect is enhanced by interposing a film, a sheet, an organic fiber, an open cell, or an air layer behind the through hole or opening. , Fill the through hole or opening with filler, or buckle it in the middle,
By reducing the diameter, the resistance to the flow of air passing through the interior is increased to enhance the sound absorbing effect.

Further, according to the present invention, it is possible to change the sound absorbing characteristic by connecting the sound absorbing material through the viscoelastic body, the open cell body, and the organic fiber, and the through hole or opening toward the sound source side. By making the cross-sectional shape of the part stepped, concave or convex, the sound absorption performance on the low frequency side is improved even with a thin thickness, and by extending the air transfer path, the air resistance is increased and the thickness of the sound absorbing material is increased. Since it can be made thin and an arbitrary resonance frequency can be set to some extent, it also has a feature that it can exhibit a sound absorbing effect over a wide frequency range.

Furthermore, since corrugated paper is used as one of the sound absorbing materials, it is also useful from the viewpoint of recycling resources.

[0011]

The structure of the present invention will be described more specifically below.

The material of the sound absorbing material in the present invention is a polymeric material such as polyethylene, polypropylene and vinyl chloride, a corrugated member made of paper, metal foil or the like, a sheet or a film having a closed cell on one or both sides. It is possible to use a member in which a large number of elongated straw-shaped members are connected, for example, a product in which straw-shaped members are connected in a blind shape.

Further, at least a part of the straw-shaped member is processed into a bellows shape or a spiral shape, and by bending this part arbitrarily, the path of the sound wave is extended and the flow resistance of the air is increased, thereby absorbing the sound. Can be increased.

Further, a sheet or film member having a large number of closed cells on one side or both sides has a cross section of 1
Since not a long and narrow through hole of a book but a large number of closed-cell portions and a film or sheet in close contact therewith are resistant to air flow, they can be preferably used in the present invention.

The material having the through hole or the opening may be laminated alternately with the fibrous material or the open-celled material, or may be wound around it.

The term "fibrous member" as used in the present invention means an organic material, not an inorganic material in view of occupational safety and health.

The material having the through hole or the opening portion suppresses the vibration of the sound absorbing material due to the flow of air by connecting at least a part of the material through the viscoelastic body, and even if it vibrates, the material is quickly attenuated. Occurs. This is because the material forming the through hole or the opening acts as a restraint material, and the viscoelastic body acts as a damping material, so that a restraining type damping effect is produced. As a result, the sound absorbing effect can be enhanced.

In addition, an air flow resistance material such as an organic fiber or an open cell is interposed in the through hole or the opening, or the air flow resistance is increased by partially buckling or reducing the diameter. Thus, it is possible to arbitrarily change the sound absorption characteristic.

Further, an organic fiber member, a sheet-shaped member, a film-shaped member, an open-cell body, a porous material, or the like is provided in at least one of before or after the through hole or the opening, or a plurality of sound absorbing materials are provided through an air layer. It is also possible to provide layers, and further to provide an organic fiber member, a sheet-shaped member, a film-shaped member, an open-cell body or a porous material in combination with an air layer.

The shape of the through hole or opening may be round, square or any other irregular shape, and is not particularly limited.
Further, as the shape of the side facing the sound source side, by making the axial cross section of the through hole or opening into a stepped shape, a concave shape, or a convex shape, it is possible to further enhance the sound absorption performance on the low frequency side.

The viscoelastic body used for producing and connecting the sound absorbing material according to the present invention is preferably room temperature crosslinkable. This is because the viscoelastic material having room temperature crosslinkability is suitable for producing a sound absorbing material because it is liquid before the crosslinking reaction, and that the reaction can be performed under certain conditions regardless of the season,
And because no solvent is used, no problems such as fire occur.

This viscoelastic body has a compressive stress of 1 Kgf /
When it is cm ² , it is desirable that the displacement amount is 5% or more and does not flow at 60 ° C or less. This is because if the displacement amount is 5% or less, the vibration prevention effect is small, and if the ambient temperature becomes high during the summer, it will flow and the sound absorbing material will not maintain its original shape and arrangement. Is.

Further, in the present invention, the viscoelastic body may be foamable or non-foamable depending on the purpose. That is, when the sound absorbing effect of high frequency sound is enhanced and the weight reduction is required, a foaming viscoelastic body is desirable, and when the sound absorbing effect of low frequency sound is enhanced and ease of molding is required. For this purpose, a non-foaming viscoelastic body is desirable.

Specifically, it is preferable to use regenerated butyl rubber, polyisobutylene, polybutadiene, etc., alone or in combination, and to which a curing agent, a plasticizer and the like are added.

[0025]

The present invention will be described in detail with reference to the following examples.

FIG. 1 shows a first embodiment in which the sound absorbing material according to the present invention is installed in a space between a floor plate 2 and a ceiling plate 3 of a building. The sound absorbing material 4 prevents the sound generated by the floor board 2 from propagating to the ceiling board 3. The sound absorbing material 4 is installed on the support plate 5, and the support plate 5 is supported between the floor plate 2 and the ceiling plate 3 by a support member (not shown). further,
A sheet-like member 6 having a sound insulating property is installed on the sound absorbing material 4.

FIG. 2 shows a sound absorbing material used in the embodiment shown in FIG. Adhesive (not shown) so that the corrugated paper 8 is stepped and the through holes 9 face upward.
Are bonded together, and both ends are made high and the center is made low to form a valley shape.

FIG. 3 shows a second embodiment of the sound absorbing material shown in FIGS. 1 and 2. A viscoelastic body (not shown) is used for the sound absorbing material shown in FIG.
It is connected through.

FIG. 4 shows a state in which the sound absorbing material shown in FIG. 3 is installed on the support plate 12 between the floor plate and the ceiling.
The corrugated board of the sound absorbing material 13 is attached by using an adhesive material (not shown), and each sound absorbing material is connected via a viscoelastic body (not shown).

FIG. 5 shows a third embodiment of the sound absorbing material shown in FIGS. 1 and 2. A metal mesh 15 is used as a support plate for the sound absorbing material, a non-woven fabric 16 is placed on the metal mesh 15, and the sound absorbing material 17 is arranged thereon. The sound absorbing material has a buckled central portion as shown in FIG. 5 (b). The buckling portion 18 increases the resistance of the air flowing inside the sound absorbing material.

FIG. 6 shows constituent members of the sound absorbing material in the fourth embodiment according to the present invention. Single-sided corrugated paper
A room temperature cross-linking type viscoelastic body 21 is filled in the concave portion of 20 and a film 22 is placed thereon. Further, a non-woven fabric 23 is placed on the film 22. In this sound absorbing material, the corrugated cardboard, the viscoelastic body 21 and the film 22 form a constrained vibration damping structure.

FIG. 7 shows a sound absorbing material obtained by laminating a plurality of members shown in FIG. The respective members are connected to each other through an adhesive material (not shown) and are formed in a rectangular parallelepiped shape.

FIG. 8 shows a fifth embodiment of the present invention using the members shown in FIGS. 6 and 7. The sound absorbing material shown in FIG. 7 has a structure in which the outer circumference is surrounded by an open cell type sponge sheet 26.

FIG. 9 shows a structural member according to a sixth embodiment of the sound absorbing material of the present invention. A large number of straw-like members 29 are arranged on the film 28, and they are connected by a room temperature crosslinkable viscoelastic body 30 to form a blind-like member.

FIG. 10 shows a sixth embodiment of the sound absorbing material according to the present invention. The cord-shaped member shown in FIG. 9 is spirally wound, and the felt 32 is wound around the outer periphery thereof. FIG. 10 (b) shows a sectional view thereof. In this embodiment, the convex side is arranged so as to face the floor plate of the upper floor.

FIG. 11 shows a sound absorbing material according to a seventh embodiment of the present invention. A large number of the sound absorbing materials shown in FIGS. 9 and 10 are arranged on the felt 37 laid on the support plate 36, and further the felt 38 is installed on the sound absorbing material. The side surfaces of each sound absorbing material 35 are supported by a support frame 39 formed in a lattice shape.

FIG. 12 shows a structural member according to an eighth embodiment of the sound absorbing material according to the present invention. The film 41 and the film 43 having the convex portion 42 are bonded together to form a closed cell 44
Is formed.

FIG. 13 is a sectional view of an eighth embodiment of the sound absorbing material according to the present invention. Nonwoven fabric on a sheet-like member having a large number of convex portions made of closed cells shown in FIG.
Install 46 and stack rubber sheet 47. This is spirally wound in the same manner as in Example 6 and Example 7, and the convex portion is installed so as to face the floorboard of the upper floor.

FIG. 14 shows a structural member according to a ninth embodiment of the sound absorbing material of the present invention. Straw member 50
The bellows part 51 is bent to form a U-shape. A large number of these are bundled to form a member.

FIG. 15 is a sectional view of a ninth embodiment of the sound absorbing material according to the present invention. The component formed by processing the straw-shaped member shown in FIG.
Secure with 53, 54, wrap a non-woven fabric 55 around it, string-like member
56 is tied around. In this embodiment, the straw-shaped member is installed with the through hole side facing the floor plate side of the upper floor.

FIG. 16 is a plan view of a tenth embodiment of the sound absorbing material according to the present invention. Plastic cardboard
58 is attached stepwise so that the outside is high and the center is low.

FIG. 17 is a sectional view showing a state in which the sound absorbing material shown in FIG. 16 is installed between a floor plate and a ceiling plate. Support plate 60
A large number of sound absorbing materials 61 are arranged on the upper side with the stepped side facing the floor board side of the upper floor, and the felt 62 is installed thereon.

FIG. 18 shows an eleventh embodiment of the sound absorbing material according to the present invention. Multiple corrugated cardboard materials of equal size
64 are attached to each other to form a rectangular parallelepiped, and a viscoelastic body 65 is surrounded on the outer peripheral portion at upper and lower two places.

FIG. 19 shows a state in which a large number of the sound absorbing materials shown in FIG. 18 are connected. The sound absorbing materials are connected while being vertically shifted alternately. In this embodiment, the connected sound absorbing material is installed like a support plate.

FIG. 20 is a plan view of the reverberation room in which the sound absorption coefficient of the sample according to each example of the present invention was measured. Each specimen is installed in the installation section 69 and measurement is performed.

FIG. 21 shows the installation site of the sample when the floor impact sound is measured for the sample according to each example of the present invention. A support member 73 is installed between a floor plate 71 on the upper floor and a ceiling plate 72 on the lower floor, and a sound absorbing material 74 is placed thereon. Floorboard
A floor impact sound is generated by the tapping machine 75 provided on the 71.

FIG. 22 shows an outline of a measuring device used for floor impact sound measurement. The sound received by the microphone 77 connected to the precision sound level meter 78 is analyzed by the frequency analyzer 79, and the analysis result is recorded by the recorder 80.

The specimens according to the examples of the present invention and the measurement results using the specimens will be described in detail below.

1. Preparation of Specimen Unit A: Corrugated cardboard paper having a thickness of 5 mm and a length of 300 mm was attached at a height of 25 mm with a butylcom adhesive to produce a sound absorbing material shown in FIG. After that, the sound absorbing material was connected using a butyl rubber sealer material having a thickness of 1 mm, and the unit A shown in FIG.
Was produced. At the time of measurement, the unit A was installed with the uneven surface facing the floorboard as shown in FIG.

Unit B: The sound absorbing material shown in FIG. 2 was compressed in the lengthwise direction, and after buckling the central part, the sound absorbing material was connected so that the unevenness of the upper part was in the same direction. This was placed on a non-woven fabric having a thickness of 8 mm laid on a wire mesh as shown in FIG. 5 to prepare a unit B.

Unit C: As shown in FIG. 6, a room temperature crosslinked viscoelastic body is formed in the recess of a single-sided cardboard paper having a thickness of 5 mm,
A 2 mm thick non-woven fabric with a single-sided film was stuck on top of it so that the film surface and the viscoelastic body adhered to each other, cut into a length of 300 mm, and then connected using a butyl rubber adhesive to obtain the sound absorbing material shown in FIG. It was made. A plurality of these were connected in the same manner as in each of the above-mentioned examples to prepare a unit C.

Unit D: As shown in FIG. 8, the same sound absorbing material as that of the unit C is surrounded by an open-cell sponge sheet having a thickness of 3 mm, which is connected with a butyl rubber adhesive to prepare a unit D. .

Unit E: Straw-shaped members made of polypropylene having a diameter of 3 mm are arranged on a polyester film having a thickness of 20 μm, and a room-temperature-reactive foam viscoelastic material is placed on the polyester film having a width of 4 cm.
To prepare the component shown in FIG.
After being cut into cm, it was wound in a spiral shape, and a felt having a thickness of 5 mm was further wound around it to produce a sound absorbing material. A plurality of the sound absorbing materials were arranged so that the convex surface faced up, and a unit E was produced.

Unit F: A unit similar to the unit E was laid over the entire surface with felt having a thickness of 5 mm to prepare a unit F shown in FIG.

Unit G: A flat film and a film having irregularities are attached to each other to produce a sheet-like member having a closed cell body shown in FIG. A non-woven fabric having a thickness of 4 mm is placed on the surface of the sheet having irregularities, and a non-vulcanized butyl rubber sheet having a thickness of 1 mm is further stacked thereon. Similar to Unit E, cut it to a length of 20 cm and then wind it in a spiral shape.
The sound absorbing material shown in 13 was produced. A plurality of these were arranged with the convex surface facing upward, and unit G was produced.

Unit H: A polypropylene straw-shaped member having a diameter of 5 mm and a length of 30 cm was processed into a bellows shape at a central portion of 6 cm, and the bellows portion was bent to form a U-shape to prepare a member shown in FIG. The bellows part and the opening part of this member are connected by a room temperature cross-linking type viscoelastic body, and then the surrounding thickness is 2 mm.
The non-woven fabric of was wrapped around to produce the sound absorbing material shown in FIG. A plurality of these were connected to produce a unit H.

Unit I: A sound absorbing material was prepared by laminating a polypropylene plastic corrugated board having a thickness of 5 mm and a length of 150 mm in a stepwise manner with a butyl rubber adhesive material at a height of 25 mm so that the central portion thereof became a concave surface. This was connected using a butyl rubber sheet having a thickness of 1 mm, and the butyl rubber sheet was also installed on the concave side. After that, it was placed on a felt having a thickness of 10 mm with the concave side facing upward, and a unit I shown in FIG. 17 was produced.

Unit J: thickness 5 mm x width 150 mm x length 10
A plurality of 0 mm cardboards were bonded together to form a rectangular parallelepiped, and a butyl rubber viscoelastic body having a thickness of 0.5 mm and a width of 30 mm was wound around the upper and lower portions of the outer periphery of the rectangular parallelepiped to produce a sound absorbing material G shown in FIG. This was alternately shifted in the direction of the through hole by a height of 50 mm and connected, to fabricate a unit J shown in FIG.

2. Test method Measurement of sound absorption coefficient in reverberation room method By using the method shown in JIS-A-1409, each test piece is placed in the reverberation room as shown in Fig. 20 and measured. went. Measurement of floor impact sound By the method shown in JIS-A-1418, a plaster board with a thickness of 12 mm was attached to the space between the floor board and the ceiling, and each test piece was placed on the plaster board and tested. 21 and 22 show the installation status of the specimen and the measuring device, respectively. The impact sound was given by a tapping machine. Presence or absence of itch occurrence The above test was carried out by three workers, and "no" indicates that all workers did not itch, and "yes" indicates that all workers itch.

The results of the above measurements are shown in the table. The comparative examples in this table refer to the case where glass wool 24K having a thickness of 50 mm was used as a sample of the sound absorbing material. Moreover, the value of the sound absorption coefficient of each unit is shown as an improvement amount with respect to the comparative example.

[0061]

[Table 1]

[0062]

The effects of the present invention will be described below based on the test results.

The unit A is an example in which the openings of the corrugated cardboard are arranged in the vertical direction and the sound absorbing materials having vertical concave sections are alternately connected so that the valleys of the adjacent sound absorbing materials are orthogonal to each other.
The sound absorption coefficient is about 0.7 on the low frequency side, and it is about 0.8 over the entire frequency range, which is a good sound absorption effect. In addition, the floor impact sound is 125 Hz compared to the glass wool which is a comparative example.
Above, a great improvement effect is obtained. Also, itching did not occur.

The unit B has the same thickness as that of the unit A, which is obtained by compressing the sound absorbing material in the lengthwise direction and buckling the central portion.
It was installed on a non-woven fabric of mm and supported by a wire mesh. This unit has a high sound absorbing effect at low frequencies, and the overall level is 0.8 or more. It can be seen that the effect of improving the floor impact sound is great and that it can be improved by one rank or more. Also, itching did not occur.

The unit C has a constrained type vibration damping structure composed of corrugated paper, a room temperature crosslinked viscoelastic material and a film, and is a laminate having organic fibers interposed. Regarding the sound absorption coefficient, almost 0.7 or more was obtained at any frequency, which also shows that the sound absorption effect is high in a wide frequency range. It can be seen that the floor impact sound can be improved by one rank or more except for 63Hz. Also, itching did not occur.

In the unit D, the sound absorbing material used in the unit C is surrounded by open-cell sponge. This unit also has a high sound absorbing effect in a wide frequency range, and the floor impact sound improving effect is also high at 63 Hz. Also, itching did not occur.

In the unit E, polypropylene pipe-shaped members arranged in the shape of a blind are connected using a room-temperature-reactive foam viscoelastic body, which is spirally wound so that the center part becomes a convex surface, and further the outer periphery is formed. The felt is surrounded by. 125
Although the sound absorbing effect is slightly lowered in the range of Hz to 250 Hz, both of them are 0.55 or more, which is a sufficient sound absorbing effect. At 315Hz and above, all frequencies are 0.8 and above, which is good. The floor impact sound is also improved by one rank or more at 250Hz or higher. Also, itching did not occur.

In the unit F, the same sound absorbing material as that in the unit E is laid with felt on the upper and lower sides. The effect of sound absorption coefficient is similar to that of the unit E, but the effect is higher. The effect of improving floor impact sound is more than one rank at 250Hz and above, and particularly excellent at 500Hz. Itching has not occurred.

The unit G is a sound absorbing material obtained by laminating a sheet having an independent foam, a non-woven fabric and felt, and spirally winding the same as in the units E and F,
This unit has communication holes formed in all directions.
In this unit, the sound absorption effect is slightly reduced at 125Hz to 250Hz, but the sound absorption effect is 0.4 or more, which is a sufficient sound absorption effect. At 315 Hz and above, the sound absorption coefficient is almost 0.8 or above. The floor impact sound is also improved by more than one rank at 250Hz or higher. Itching did not occur even in this unit.

The unit H is an example in which the opening of the communication hole is not in the direction opposite to the sound source side. The straw-like member is provided with a bellows portion, and the bellows portion is bent to form a U-shaped member. A non-woven fabric is enclosed in a high-speed type vibration control structure in which a large number of members are connected at the bellows part and the upper part by a room temperature reaction type viscoelastic body. It can be seen that this unit has a high sound absorption effect, with a sound absorption coefficient of 0.8 or more over the entire frequency range. The effect of improving the floor impact sound is also high, and it can be seen that it can be improved by one rank or more at frequencies other than 63 Hz. Itching did not occur even in this unit.

The unit I is made of a plastic corrugated cardboard member, and a rubber sheet is attached to the upper surface and the side surface of a sound-absorbing material which is formed so that the center is low and the four sides are gradually raised at intervals of 25 mm in the four sides. The rubber sheet surface is on top of the felt. Also in this unit, the sound absorption coefficient is good from low frequency to high frequency, and it is shown that the floor impact sound can be improved by one rank or more in the entire frequency range. Also, itching did not occur.

In the unit J, a plurality of corrugated cardboards having the same height are attached to each other, and the outer periphery thereof is surrounded by a butyl rubber viscoelastic body, which are alternately shifted by 50 mm in the direction of the communication hole to be connected to each other so that a space is provided at the bottom. It is a thing. This unit is
In particular, the sound absorption effect at the low frequency side was high, and a sound absorption coefficient of 0.8 or more was obtained in the entire frequency range. It was found that the effect of improving floor impact sound was also high and that it could be improved by one rank or more at any frequency. Also, itching did not occur.

In the comparative example, as the sound absorbing material, the thickness of 24 mm of 24K is used.
This is an example using glass wool. Below 200Hz, the sound absorption effect is low and below 0.5. Especially, it can be seen that the effect cannot be expected at 125 Hz. Further, since it is an inorganic fiber, itching is inevitable during work.

From the above, the sound absorbing material according to the present invention has a large sound absorbing effect over a wide frequency range.
It was confirmed that it can be used in place of the inorganic fiber-based sound absorbing material that is mainly used at present, has better sound absorbing performance, and that itching during work does not occur. It was also found that the cardboard paper treated as waste can be effectively used, and even if it is bent and buckled into a box shape, it can be sufficiently used.

Further, by forming the surface in a concavo-convex shape, an effective sound absorbing effect is exhibited particularly on the low frequency side.
It was also found that by extending the length of the air passage as shown in the unit G, a high sound absorbing effect can be obtained even if the thickness of the sound absorbing material is reduced.

Therefore, the present invention has been found to be effective in reducing noise in various fields and also as a potential effective use of waste. Therefore, the present invention makes a great contribution not only in improving the noise environment in each field, but also in terms of effective use of resources.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a state in which a sound absorbing material according to a first embodiment of the present invention is installed in a space between a floor and a ceiling of a building.

FIG. 2 is a perspective view of a sound absorbing material formed by pasting corrugated cardboard sheets according to a second embodiment of the present invention.

FIG. 3 is a perspective view showing a state in which the sound absorbing members shown in FIG. 2 are connected so that valley portions of adjacent sound absorbing members are alternately arranged.

FIG. 4 is a cross-sectional view showing a state where the sound absorbing material shown in FIG. 3 is installed on a support member.

FIG. 5 is a cross-sectional view showing that the sound absorbing material shown in FIG. 2 according to the third embodiment of the present invention is provided with a buckling portion at the center and is installed on a supporting member.

FIG. 6 is a cross-sectional view showing constituent members of a sound absorbing material according to fourth and fifth embodiments of the present invention.

FIG. 7 is a perspective view of a sound absorbing material according to a fourth embodiment of the present invention.

FIG. 8 is a perspective view of a sound absorbing material according to a fifth embodiment of the present invention.

FIG. 9 is a perspective view of constituent members of a sound absorbing material according to sixth and seventh embodiments of the present invention.

FIG. 10 is an external view and a cross-sectional view of a sound absorbing material according to a sixth embodiment of the present invention.

FIG. 11 is a view showing a state in which a plurality of sound absorbing materials according to a seventh embodiment of the present invention are installed.

FIG. 12 is a perspective view of constituent members of a sound absorbing material according to an eighth embodiment of the present invention.

FIG. 13 is a sectional view of a sound absorbing material according to an eighth embodiment of the present invention.

FIG. 14 is a perspective view of constituent members of a sound absorbing material according to a ninth embodiment of the present invention.

FIG. 15 is a sectional view of a sound absorbing material according to a ninth embodiment of the present invention.

FIG. 16 is a view of the sound absorbing material according to the tenth embodiment of the present invention as seen from above.

FIG. 17 is a cross-sectional view showing that the sound absorbing material according to the tenth embodiment of the present invention is installed on a support member.

FIG. 18 is a perspective view of a sound absorbing material according to an eleventh embodiment of the present invention.

FIG. 19 is a perspective view showing a state in which a plurality of sound absorbing materials according to an eleventh embodiment of the present invention are connected.

FIG. 20 is a diagram showing the installation site of the sound absorbing material in the reverberation room where the sound absorption coefficient of the sample according to each example of the present invention was measured.

FIG. 21 is a diagram showing the installation site of the sound absorbing material at the time of floor impact sound measurement of the sample according to each example of the present invention.

FIG. 22 is a schematic diagram of a floor impact sound measuring device.

[Explanation of symbols]

2, 71 Floor slab 3, 72 Ceiling board 4, 7, 13, 17, 24, 25, 31, 35, 45, 52, 57, 61, 63,
74 Sound absorbing material 5, 12, 37, 60, 73 Support plate 6 Sheet-like member 8, 64 Corrugated paper 9 Through hole 15 Wire mesh 16, 23, 46, 55 Non-woven fabric 18 Buckling part 20 Single-sided corrugated paper 21, 30, 53, 54 Room temperature cross-linking type viscoelastic body 22, 47 Rubber sheet 26 Open-cell type sponge sheet 28, 41, 43 Film member 29, 50 Straw member 65 Viscoelastic body 32, 37, 38, 62 Felt 33, 48 Space 39 Support Frame 42 Convex section 44 Closed cell body 51 Bellows section 56 String member 58 Plastic cardboard 68 Reverberation chamber 69 Specimen installation section 75 Tapping machine 77 Microphone 78 Precision sound level meter 79 Frequency analyzer 80 Recorder

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G10K 11/162 G10K 11/16 A 11/16 D

Claims (15)

[Claims] 1. A sound-absorbing material, which is formed by laminating a plurality of corrugated cardboard-shaped members obtained by laminating at least one film or sheet and a corrugated or folded plate-shaped film or sheet. 2. A sheet-like member having a large number of closed cells, which is obtained by laminating a film or a sheet and a film or a sheet having a large number of convex portions formed on one surface thereof, or is formed by rolling. Sound absorbing material. 3. One surface of the film or sheet,
A sound-absorbing material, which is formed by stacking or winding sheet-like members in which band-shaped members made of rubber or foam are attached at arbitrary intervals. 4. A sound-absorbing material, which is formed by stacking or winding a plurality of straw-shaped members having through holes, which are bundled or connected in a plane. 5. A sound absorbing feature, characterized in that a part of a straw-shaped member is processed into a bellows shape, and the bellows portion is bent to form a plurality of members having a long sound propagation path length, which are bound or connected together. Material. 6. The sound absorbing material according to any one of claims 1 to 5, wherein at least a part of the members is connected by a viscoelastic body. 7. The sound absorbing material according to claim 1, wherein at least a part of the through hole or the opening is filled with a filler, buckled or reduced in diameter to increase air flow resistance. Sound absorbing material characterized by that. 8. The sound absorbing material according to any one of claims 1 to 7, wherein a sheet-like member made of organic fibers or open cells is provided on one surface of the constituent member and then laminated. Characteristic sound absorbing material. 9. The sound absorbing material according to any one of claims 1 to 8, wherein at least a part of the outer periphery of the sound absorbing material is
A sound absorbing material, characterized in that an organic fiber, an open cell body or a viscoelastic body is provided in parallel with a through hole or an opening. 10. The sound absorbing material according to claim 1, wherein the organic fiber, the foam, the film, the sheet or the porous material is provided on at least one side in a direction perpendicular to the through hole or the opening. A sound absorbing material characterized by having a material. 11. The sound absorbing material according to any one of claims 1 to 10, wherein an air layer is provided on a back surface of the sound absorbing material. 12. The sound absorbing material according to claim 1, wherein a large number of members are provided in layers. 13. The sound absorbing material according to any one of claims 1 to 12, wherein the members are connected in a step shape, a concave shape, or a convex shape so that the through holes or openings are in the vertical direction, A sound-absorbing material characterized by arranging this surface toward the sound source side. 14. The sound absorbing material according to claim 6 or 9, wherein the viscoelastic body has room temperature crosslinkability, and the displacement is 5% or more when the compressive stress is 1 kg / cm ^2. 60 ° C
Sound absorbing material characterized by not flowing below. 15. The sound absorbing material (A) according to claim 1, 2.
One or more sound absorbing materials selected from the sound absorbing material (B), the sound absorbing material (C) according to claim 3, the sound absorbing material (D) according to claim 4, and the sound absorbing material (E) according to claim 5. A sound-absorbing material, which is formed by stacking or winding materials individually or in combination.