JPH06191960A - Sound absorbing and insulating composite material and its production - Google Patents

Abstract

PURPOSE:To provide a sound absorbing and insulating composite material, capable of effectively shutting off noise in a low-frequency band and having excellent sound absorbing and insulating effects even if the thickness is reduced. CONSTITUTION:A sheet having openings is impregnated with a composite material composition containing a porous inorganic substance, metallic particles and a binder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound-absorbing and sound-insulating composite material capable of efficiently absorbing various noises, particularly noises in a low frequency range, for example, noises of 500 Hz or less, and intercepting the noise, and its manufacture. It is about the method.

[0002]

2. Description of the Related Art Various sound absorbing and sound insulating materials have been commercialized so far. Among them, those using inorganic porous materials include sintered metal type, foam glass type, ceramic type, cement type and the like, and those using organic materials include rubber sponge, plastic foam, natural polymer porous type. Examples include a body and a fiber aggregate. These are used individually and as a composite having a thickness of several 10 mm, but there is a problem that noise in a low frequency range of 500 Hz or less cannot be effectively blocked. Further, since the thickness is as thick as several tens of millimeters, a thinner sound absorbing and insulating material is desired. However, if the conventional sound absorbing and insulating material is simply thinned, the noise insulating property in the middle and high frequency range is lowered and the There is a problem that the noise barrier property in the frequency range is further reduced.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sound absorbing and sound insulating composite material capable of effectively blocking low frequency noise. Another object of the present invention is to provide a sound absorbing and sound insulating composite material which has excellent sound absorbing and sound insulating effects even when the thickness is reduced. A further object of the present invention is to provide an efficient manufacturing method of such a sound absorbing and sound insulating composite material.

[0004]

The present invention has been made based on the finding that the above problems can be efficiently solved by using a porous inorganic material and metal particles as essential components and adhering them to each other with a binder. It was. That is, the present invention provides a sound-absorbing and sound-insulating composite material, wherein a composite material composition containing a porous inorganic material, metal particles and a binder is impregnated in a sheet having openings. The present invention also provides a sound absorbing and sound insulating composite material characterized by containing porous inorganic material, metal particles, fibers and a binder.

The porous inorganic material used in the present invention includes:
Shirasu foam, foam glass, ceramics, perlite,
Particle size of vermiculite, shirasu, natural zeolite (zeolite), carbon (including activated carbon), etc. is 1μ-5mm, preferably 5μ
˜500 μ of particulate matter (including powdery matter).
In the present invention, one kind or a mixture of two or more kinds thereof can be used.

Particularly when one of these is used, it is preferable to use one having pores having a pore radius of 2Å to 15Å, particularly preferably 3Å to 10Å. Examples of such a porous inorganic material include natural zeolite. Natural zeolite has a particle size range of 5
Although there is a range of 0 mm to 61 μ or less, the most desirable particle size is 60 μ to 250 μ, has pores of 3Å to 10Å, and has a component SiO _{2 of} 70 wt% (hereinafter abbreviated as%),
Examples include Al ₂ O ₃ 10 to 15%, Fe ₂ O ₃ 1 to 2%, MnO 0.05% or more, and CaO 2%. Natural zeolite is easily available, for example, under the trade name Izcalite: Izumo Chemical Co., Ltd.

When a mixture of two or more kinds is used,
Is a large number of pores having the above-mentioned pore radius of 2Å to 15Å.
Use the porous inorganic material in combination with the other porous inorganic material described above
Is good. Here, other porous inorganic materials include shirasu
Foam is preferred and particle size is 5μ-500μ, desirably
20μ-60μ, bulk specific gravity 0.13g / cm³~ 0.50g
/cm³, Preferably 0.3 g / cm³~ 0.5 g / cm³,component
 SiO₂ 70-80%, Al ₂O₃10-14%, Fe₂O₃1 to
3%, Na₂0.2-5%, K₂O 1-5%, loss 2-5%
It is better to use one in the range of.

Examples of the metal particles used in the present invention include iron powder, copper powder, aluminum powder, stainless powder, and other metal powder having a particle size of 5 to 500 μm, with aluminum powder being preferred. This is because it is lighter and cheaper than other metals. Examples of the aluminum powder include a pulverized product of aluminum having an arbitrary purity, and a powder composed of particles having a spherical shape or a shape close to this, and it is preferable to use a pulverized product of 99% or more pure aluminum. The particle size is, for example, 850μ to 45μ, but 200μ to
The best sound absorption and sound insulation effect can be obtained by using 10 μm.

In the present invention, various organic and / or inorganic binders can be used as the binder for molding the above raw materials. Examples of organic binders include polyvinyl acetate and polyvinyl alcohol. Examples of the inorganic binder include alkali metal silicate salts. Of these, inorganic binders, which are non-flammable or semi-inflammable materials, are preferable, and sodium silicate is particularly preferable. This is because water can be added when the viscosity of the slurry is adjusted in the step of adding the sodium silicate after stirring and mixing the inorganic materials, and then again mixing and stirring to make the slurry. Also, since sodium silicate, which is solidified at a certain temperature or higher in the subsequent drying step, acts as a binder and becomes a spherical carmel shape, which further forms pores and improves the effect as a sound absorbing material. Is.

In the present invention, the ratio of the porous inorganic material having pores having a pore radius of 2Å to 15Å and the metal particles and the binder, or the porous inorganic material having pores having a pore radius of 2Å to 15Å and other porous materials. The ratio of the hydrophilic inorganic material to the metal particles and the binder can be arbitrarily set, but the pore radius is 2Å to 1
The ratio of porous inorganic material having 5Å pores to metal particles is 3
It is preferable that the ratio is / 1 to 1/3 (weight ratio). Further, the ratio of the porous inorganic material having pores with a pore radius of 2Å to 15Å to other porous inorganic materials and metal particles is 3/1/1 to 1/3.
It is preferably / 3 (weight ratio). Also, a mixture of these particles and a binder (for example, a solvent such as water is added in an amount of 20 to 8).
It is preferable that the ratio of (containing 0%) is 4/1 to 1/3 (weight ratio).

In the first aspect of the invention, a slurry obtained by adding a liquid binder to a mixture obtained by mixing and agitating with the above-mentioned granular raw material and mixing and agitating again is used to prepare a sheet having pores, for example, a fibrous sheet ( Apply to glass paper, non-woven fabric, metal fiber cloth). This is performed, for example, by applying or spraying the slurry to a sheet using an impregnating machine such as a roll coater, a knife coater, a knife roll type coater, a reverse knife type coater, a knife blanket type coater, or a spray nozzle machine. be able to. Then, it is dried by a conventional method to obtain a sheet-like sound absorbing and sound insulating composite material (about 0.4 mm thick). At this time, the impregnation amount can be arbitrary, but 50 to 700 g / m ² (dry basis),
It is preferably 100 to 500 g / m ² .

In the present invention, one sheet thus produced can be used as a sound absorbing and sound insulating composite material, but it is preferable to use a plurality of laminated sheets. For example, a laminated sheet can be manufactured by stacking a plurality of sheets impregnated with the slurry and then drying them. Further, a liquid binder is applied to one dried sheet produced by the above method, the dried sheet is superposed on the dried binder, and this operation is repeated until a desired number of sheets are obtained, and then the laminated sheet is dried. It can be manufactured. At this time, if a metal sheet (100 μ to 1000 μ) such as an aluminum sheet is provided as the outermost layer, the sound insulation effect can be more effectively achieved. Dry 14
It may be carried out at 0 to 220 ° C., preferably 150 to 180 ° C.

More specifically, in the case of a two-layer sheet, one layer of fiber sheet impregnated with slurry and one layer of aluminum sheet are laminated with a liquid binder. In the case of a three-layer sheet, two layers of the fiber sheet impregnated with the slurry and one layer of the aluminum sheet are lined (after laminating a liquid binder between the two layers of the fiber sheet, one layer of the aluminum sheet is further laminated with the liquid binder). Add). In the case of a four-layer sheet, three layers of fibers are laminated as described above, and then one layer of aluminum is laminated. In this way, 2-10
Lamination of layers can be performed. This is because, if the four-layer structure is the basic form and four or more layers are laminated, the sound absorbing and sound insulating effects are further improved unless the above-mentioned basic form is changed.

By manufacturing in this way, a 4-layer laminated product having a thickness of about 2 mm and an areal density of ^{2 to 3} kg / m ² can be obtained. In the second invention, it is necessary to use fibers in addition to the above-mentioned raw material porous inorganic material, metal particles and binder. Here, as the fibers, not only fibers that are separated for each fiber but also a crushed product of a sheet produced by knitting the fibers, for example, chips can be used. At this time, an organic binder, for example, a vinyl acetate resin-based emulsion binder (addition amount of vinyl acetate: 10 to 50%, water content: 90 to 50%) is added in an amount of 20 to 60%, preferably 50% of the total amount of the binder. It is better to improve the adhesion to. When fibers are used, it is possible to effectively prevent separation of the inorganic material and the metal particles.

Here, the ratio of the porous inorganic material having pores having a pore radius of 2Å to 15Å, metal particles and fibers is 3/1 /.
It is preferably 1 to 1/3/2 (weight ratio). Further, the ratio of the porous inorganic material having pores with a pore radius of 2Å to 15Å to other porous inorganic materials, metal particles and fibers is 3/1/1.
It is preferable to set it to / 1-1 / 3/3/2 (weight ratio).
Further, the ratio of the particle mixture and the binder (for example, containing 20 to 80% of a solvent such as water) is 4/1 to 1 /.
It is preferably 3 (weight ratio).

As the fiber, it is preferable to use a chopped strand of glass fiber having a diameter of several μ (glass fiber cut into short pieces). Stir this blended raw material with a mixer to make a viscoelastic liquid (viscosity 200 cp to 700 cp),
This viscoelastic liquid is sprayed on the adherend with an air spray or an airless sprayer that uses compressed air. In this case, the spray thickness is preferably 1 mm to 10 mm. Furthermore, when a large amount of the same shape is to be produced, a mold release agent is applied to the surface of the mold, and the viscoelastic liquid is sprayed or brushed, cured appropriately, then removed and dried to obtain the same shape. You can make a lot of things.

[0017]

According to the present invention, a thin sheet-like sound absorbing and sound insulating composite material (for example, 0.5 to 10 mm thick) having a sound absorption coefficient in the low frequency range significantly superior to that of other materials is provided. Further, even if the noise source has a complicated shape, it can be sprayed on the outer circumference without any gap, so that the noise can be absorbed or shielded very effectively. Next, the present invention will be described with reference to examples.

[0018]

【Example】

Example 1 Shirasu Balloon (trade name Winlite: Idiji Kasei Co., Ltd., particle size range 20 μ-60 μ) 25 to 20%, porous zeolite particles (trade name Izcalite: Izumo Chemical Co., Ltd., particle size 60 μ-250 μ) 10 to 15%, aluminum powder (purity 99%, 10 μ to 200 μ) 15 to 2
0% and sodium silicate No. 3 50-45% are mixed and stirred (propeller blade 50-100 rpm, stirring for 5 minutes) to 10
A slurry-like mixed solution having a viscosity of 0 cp to 1000 cp was obtained.

This mixed solution was mixed with a glass fiber non-woven fabric (thickness 5
-10 μm, basis weight 36 g / m ² , width 1000 mm), and then coat with a hot air dryer at 150 ° C. for 5
After drying (water evaporation) for 10 minutes, the sheet-shaped (1
Layer) A sound absorbing and sound insulating composite material was obtained (thickness 0.5 mm, weight 300 g / m ² ). Sodium silicate No. 3 was applied between the sheet-like sound absorbing and sound insulating composite material (glass fiber nonwoven fabric) thus obtained and an aluminum sheet (100 μ to 150 μ, true specific gravity 2.6 g / cm ³ , width 1000 mm), A three-layer structure consisting of glass fiber non-woven fabric / glass fiber non-woven fabric / aluminum sheet is laminated and then 1 with a hot air dryer.
The sheet-like sound absorbing and sound insulating composite material of the present invention was manufactured by drying (water evaporation) at 50 ° C. for 5 to 10 minutes (thickness 2.0 mm,
Weight 2000 g / m ² ).

In the same manner, a sheet-like sound-absorbing and sound-insulating composite material having a four-layer structure composed of glass fiber non-woven fabric / glass fiber non-woven fabric / glass fiber non-woven fabric / aluminum sheet was manufactured (thickness 2.0 mm, weight 1900 g / m ² ). . The sound absorption coefficient of the sheet-shaped sound-absorbing and sound-insulating composite material of the present invention is determined by JIS A
It was measured by a normal incidence sound absorption coefficient by the 1405 tube method. At this time, in the case of a sheet having a three-layer structure or a four-layer structure, the measurement was performed by installing the aluminum layer so that the aluminum layer is the outermost side with respect to the noise source. The results are shown in Table-1. still,
The numerical values in the table are sound absorption rates (%).

[0021]

[Table 1] Table 1 1-layer product 3-layer product 4-layer product 100 * 117 * 0 * 50 * 100 * Center frequency (Hz) mm mm mm mm mm 125 Hz 18% 48 58 67 67 49 200 Hz 25 40 35 35 52 52 250 Hz 32 43 29 29 40 87 315 Hz 61 53 53 25 65 97 500 Hz 58 60 60 21 96 72 1000 Hz 17 19 56 35 35 28 In the table, * indicates the position where the sound absorption coefficient was measured, and it indicates the direction from the sound absorption and sound insulation composite sheet to the outside (from the noise source). Distance (in the direction of going away).

As is clear from the results shown in Table 1, according to the present invention, it is possible to obtain a lightweight and thin sound absorbing and sound insulating composite material having excellent sound absorbing and sound insulating properties. Particularly, the sound absorption coefficient in the low frequency range was good.

Example 2 Shirasu balloon (trade name Winlite: Idiji Kasei Co., Ltd.) 20 to 10%, porous zeolite (trade name Izcalite: Izumo Chemical Co., Ltd.) 10%, aluminum powder (purity 99%, 10 μm) ~ 200μ) 15-20%, vinyl acetate resin emulsion (10% vinyl acetate containing adhesive) 20-25%, sodium silicate No. 3 30-25% and glass fiber chop strands (10μ × 2mm) 5-1
0% mixed and stirred (propeller blade, 50μ-100r.p.
After stirring for 10 minutes, a slurry-like mixed liquid having a viscosity of 200 cp to 500 cp was obtained.

This was sprayed onto a sound source generator with an air spray gun so as to have a thickness of 2 mm to 5 mm, and the applied material was dried at 150 ° C. to 200 ° C. for 15 to 20 minutes, resulting in excellent sound absorption and sound insulation effects. was gotten.

Claims (4)

[Claims] 1. A sound-absorbing and sound-insulating composite material, characterized in that a sheet having pores is impregnated with a composite material composition containing a porous inorganic material, metal particles and a binder. 2. A method for producing a sound-absorbing and sound-insulating composite material according to claim 1, wherein a sheet having pores is impregnated with a solution containing a porous inorganic material, metal particles and a binder and then dried. . 3. A sound absorbing and sound insulating composite material comprising a porous inorganic material, metal particles, fibers and a binder. 4. A method for producing a sound absorbing and sound insulating composite material, which comprises applying a liquid material containing a porous inorganic material, metal particles, fibers and a binder around a noise source.