JPH09317047A - Sound insulation panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound insulation material having light weight, excellent sound absorbing and sound insulating functions and ensuring inexpensiveness by applying specific values to a pore area, the number of pores per area and the density of a porous layer, regarding the porous layer contained in a sound insulation material. SOLUTION: A sound insulation material containing a porous layer made of nonwoven fabric, cloth, a sponge, a synthetic resin layer or the combination thereof, is manufactured, and a porous layer is formed on the surface of the sound insulation material in the vicinity of the side exposed to an incident sound wave. Also, the porous layer is formed to have 200 or more pores per cm<2> , each having an area equal to or less than 2,000μm<2> and preferably, to have 500 or more pores per cm<2> , each having an area equal to or less than 1,000μm<2> . Furthermore, the density of the porous layer is taken at a value equal to or above 0.1g/cm<3> , and preferably at a value equal to or above 0.5g/cm<3> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The soundproof material of the present invention relates to a material for absorbing sound and insulating sound. Especially building materials, civil engineering materials, aviation
The present invention relates to materials for vehicles and ships, sound absorbing materials such as acoustic materials, and sound insulating materials.

[0002]

BACKGROUND OF THE INVENTION Generally, recycled felt is used as a soundproof material.
Polyurethane foam, polyethylene foam, etc. are used. These soundproofing materials can improve their soundproofing performance by increasing their areal weight, that is, their weight. However, increasing the basis weight will increase the cost, and the increase in weight will go against the trend of light, thin, short, and small demands of the times.

In recent years, it has been proposed to use a non-woven fabric as a soundproof material instead of a recycled felt. For example, JP-A-7-97754 discloses a polyester fiber having a fiber diameter of 4 denier or less and a spring constant of 80000 N / m.
The following non-woven fabrics have been proposed. The spring constant is correlated with the fiber diameter, and it is said that the use of a soundproof material having a small fiber diameter improves the soundproof performance. However, it is not the case that the microfiber knitted fabric having a very small fiber diameter has excellent soundproofing. There is almost no soundproofing with only microfiber knitted fabric. The soundproofing cannot be improved by simply reducing the fiber diameter.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a lightweight soundproof material which is excellent in sound absorption and sound insulation at low cost.

[0005]

As a result of various studies on the surface material of the soundproof material, the inventors have found that the structure of the surface material in the sound incident direction has a great influence on the sound absorbing property and the sound insulating property. Moreover, as a result of further research, the pore size of the surface material has a great influence on the sound absorption and sound insulation properties, and in particular, the number of holes with a surface area of 2000 μm ² or less has a large effect on the sound absorption and sound insulation properties. It became clear that

The present invention is a soundproof material having a porous layer having 200 holes / cm ² or more with an area of 2000 μm ² or less. If the number of holes is less than 200 / cm ² , the soundproofing effect is poor. It is preferably 1000 pieces / cm ² or more. Also,
More preferably small pores, ie the pore area is 1000 μm
^{It is 2} or less and the number is 200 / cm ² or more. More preferably, it is 500 pieces / cm ² or more.

The porous layer may be non-woven fabric, cloth, sponge, resin layer and combinations thereof. When the non-woven fabric or cloth is made of microfibers and has a high density, the interfiber gap can be reduced. These gaps correspond to the holes in the present invention. The holes in this case are actually communicating. Moreover, when the communicating parts are taken, the cross-sectional area is often not uniform. In the case of a communicating hole, if the cross-sectional area of the hole is partially less than or equal to the area defined above, it is calculated as one hole.

In the present invention, the pores on the surface of the porous layer are measured and used as the representative value of the pores of the porous layer. The area and the number of holes were obtained by analyzing the data input with a stereomicroscope with an image analyzer.
As the image analysis software, V10 manufactured by Toyobo Co., Ltd. was used. The area of the holes was 0 to 500, 501 to 1000, and the holes were collectively counted for each size of 500 μcm ² .

In the case of sponges, the holes are often independent. It is preferable that the holes are independent from each other in terms of soundproofing, as compared with the case where the holes are connected. Examples of sponge materials include polymers such as polyurethane, polyethylene, polystyrene, polyvinyl alcohol, polyvinyl acetate, polyvinyl chloride, etc.
There is a foam.

Further, even if the diameter of the holes of the non-woven fabric or the cloth itself is large, the holes can be made small by closing the holes with an appropriate resin or the like. Porous layers formed in this way can also be used. The type of resin mentioned here is not particularly limited. Natural materials such as starch, modified starch, hemicellulose,
There are cellulose and polysaccharides, and there are proteins (eg collagen, sericin, chitin) and the like.

Further, there are synthetic resins. For example, polymers of (meth) acrylic, vinyl acetate, vinyl chloride, ethylene, propylene, styrene, isoprene, chloroprene, butadiene, maleic acid, fumaric acid, (meth) acrylic acid and its esters and amides, and copolymers thereof, And nylon resin, polyester resin, polyurethane resin, epoxy resin, phenol resin and the like.

As a method for applying the above-mentioned resin to a non-woven fabric or a cloth, a spray method, an impregnation method, a coating method or the like can be applied. If the viscosity of the resin applied is large, it becomes difficult to open the holes. The lower the viscosity of the resin, the better. When the viscosity of the resin becomes low, the amount of adhesion decreases, and it may be necessary to apply the resin in several divided portions. Repeated coating is economically unfavorable, so it is necessary to select the viscosity appropriately. The resin may be a solution, emulsion or melt. Among them, an emulsion having a low viscosity is preferable for its concentration. In the same sense, the molecular weight of the above resin is preferably as small as possible without causing a problem in strength.

The easiness of opening the holes varies depending on the thickness of the fibers forming the non-woven fabric or the cloth. That is, the thinner the fibers constituting the resin, the easier the resin is attached. Therefore, the viscosity of the resin can be reduced and the holes can be easily opened, which is preferable. The same applies to wetting of the fibers. That is, it is preferable to select a fiber oil agent that is easily wetted. In the case of a fabric, the same consideration should be given to the knitting and weaving structures.

It is also possible to make small holes in the film or resin by a known mechanical or electrical method, and such a processing method may be adopted. However, it is not economically advantageous.

When the porous layer is made of the non-woven fabric itself and is not processed, the diameter of the pores is not reduced unless the fiber diameter of the fibers constituting the non-woven fabric is small, and improvement in sound absorbing performance cannot be expected. At least single fiber diameter is 1
It is 0 μm or less. It is preferably 5 μm or less, more preferably 3 μm or less. As a method for producing a non-woven fabric having a small fiber diameter, there is a melt blow method, and products such as polypropylene, polyethylene, polyester and polyurethane are already on the market. These are commercially available in the form of being laminated with spunbonded nonwoven fabric, for example, commonly known as SMS.

A nonwoven fabric using split fibers can also be used as a porous layer because a nonwoven fabric having a small fiber diameter can be produced. In this case, there are a method in which a nonwoven fabric is manufactured and then divided by chemical or heat treatment, and a method in which a nonwoven fabric is manufactured and divided at the same time by a spun lace.

A thermal bond non-woven fabric containing heat fusion fibers can also be used as the porous layer. The heat fusion causes the fiber gaps to be crushed, and the same effect as resin processing can be obtained. The heat fusion fiber content is preferably 50% by weight or more,
70% by weight or more is more preferable. More preferably 100
% By weight.

The heat-sealing fibers are already on the market, and side-by-side type and core-sheath type heat-bonding fibers are often used. These are fibers composed of polymers having different melting points, and the melting points differ depending on the type of polymer. 110, 13
There are also heat fusion fibers having low melting point components of 0, 150, 170 and 200 ° C.

As the type of polymer, polyolefin, copolymerized polyester, nylon and modified products thereof are often used as the low melting point polymer. As the high melting point polymer, polypropylene, polyethylene terephthalate, polybutylene terephthalate, nylon 6,
Nylon 66 is often used. The denier of the heat-sealing fiber is usually 2 denier, and a smaller fiber diameter is preferable because the fiber gap is smaller.

When fibers other than the heat-sealing fibers are made of a polymer similar to the sheath component of the heat-sealing fibers, the number of bonding points increases, so that the bonding effect increases. Typical synthetic fibers include, for example, polypropylene, polyethylene terephthalate, polybutylene terephthalate, nylon 6, nylon 66, etc., and recycled fibers such as viscose rayon,
Examples of natural fibers such as acetate include cotton, hemp, wool, silk, etc., which may be appropriately selected and used according to the application.

The method for producing the above-mentioned non-woven fabric is, for example, a card,
A manufacturing method using a cross ray, a draw, or a needle punch may be used. Alternatively, a random card or needle punching method may be used.

In the present invention, these non-woven fabrics can be used as a porous layer. The split fiber includes a sea-island type, a composite type including a star-shaped separating component and a component that is divided into small components, and a multi-layer type. For example, there is a composite fiber in which the polymer to be separated is nylon 6 and the polymer to be divided is polyethylene terephthalate.

In addition to non-woven fabrics, in recent years, multi-filament formation has progressed, and knitted fabrics made of multi-filaments having a small single fiber diameter are commercially available. Such knitted fabrics can also be used as the porous layer. As for ultrafine fibers, denier of single fiber is manufactured up to about 0.5 denier. In the case of polyester, the fiber diameter is about 6 μm. Since it is a multifilament, the knitting and weaving process is technically established. Also, split fibers can be used in the same manner as nonwoven fabric. Woven fabrics that are more dense than knits are preferred. The woven structure includes plain weave and twill weave, but a fine structure is preferable.

It is preferable that the above-mentioned porous layer is a dense layer because the pore diameter becomes smaller. Therefore, it is preferable that the density is high. That is, it is preferable to increase the density of the non-woven fabric by embossing or calendering. The knitted fabric also preferably has a dense structure, and it is preferable to increase the density by embossing or calendering. The density of the porous layer is 0.1g
/ Cm ³ or more, preferably 0.3 g / cm ³ or more, more preferably 0.5 g / cm ³ or more.

The basis weight of the porous layer is preferably 20 g / cm ² or more, more preferably 50 g / cm ² or more. If the basis weight of the porous layer is too small, the improvement of the soundproofing effect of the soundproofing material cannot be expected to be great.

The soundproof material of the present invention comprises the above porous layer and the porous layer described below. Polyurethane foam, polyethylene foam, non-woven fabric, etc. can be used for the porous layer. Also, a combination of these may be used. The cells of foamed polyurethane and polyethylene are preferably closed cells because they have better sound absorbing and sound insulating properties than open cells. Although it depends on the required level of performance of the soundproofing product and the soundproofing property of the porous layer itself, when the porous layer is a sponge alone, the sound absorbing property can be exhibited if the basis weight is 5 g / cm ² or more. Preferably 10 g / cm
² or more. When the non-woven fabric layer is used alone, 300 g /
m ² or more, preferably 500 g / m ² or more.

That is, since the effect of the present invention is improved in a manner proportional to the sound absorption coefficient of the porous layer, if the sound absorption coefficient of the porous layer alone is too small, the absolute value of the sound absorption coefficient does not increase. However, the effects of the present invention cannot be sufficiently exhibited. 2 kHz
The sound absorption coefficient is dramatically increased by stacking the porous layer having a sound absorption coefficient of 10% or more and the soundproof material of the present invention. Therefore, the sound absorption coefficient of 10% or more alone is preferable for the porous layer, further 25% or more, more preferably 40% or more.
It is preferable to use a porous layer having a sound absorption coefficient of not less than%. Further, it is preferable that the porous layer has low air permeability to improve the sound absorption coefficient.

The porous layer has a density of 0.001 to 0.1 g /
cm ³ is preferred. The soundproofing performance tends to decrease as the density increases. The density here means an apparent density. If the density is too high, the soundproofing property will not be improved for the basis weight and the cost will be increased. If the density is too low, the mechanical properties will be reduced and it will generally be difficult to use.

The feature of the present invention resides in that the soundproofing performance is remarkably improved by laminating the above porous layer and porous layer. Further, when using the soundproofing material of the present invention, it is necessary to use the porous layer facing the sound source. Therefore, back and front and 2
When there is a possibility that a sound source exists in the direction, it is advisable to stack the porous layers on both sides of the porous layer.

The porous layer and the porous layer may be laminated by using an adhesive. The effects of the present invention can be obtained by simply stacking. The adhesive may be a general emulsion type adhesive such as an acrylic adhesive, an EVA adhesive, a Poval adhesive, or a polyurethane adhesive. A hot melt type adhesive can also be used. There are polyester type and EVA type. Also, spray polyethylene powder,
It can also be bonded by heat treatment. Binder fibers may be used in the porous layer and the porous layer and bonded by heat treatment.

The porous layer and the porous layer may be held by separate supports and mechanically laminated. For example, when they are stored in a frame and laminated, or when they are laid on a floor, they are mechanically laminated, so that they function as the fiber product of the present invention without using an adhesive. be able to. Alternatively, they may be bonded by needle punching.

The soundproof material of the present invention can be used in combination with other soundproof materials. Further, a film may be laminated and used together with the porous layer. It is also possible to use by sandwiching the film between the porous layer and the porous layer. When the soundproof material is laminated in two or more layers, the effect of the porous layer can improve the soundproof effect of the subsequent porous layer.

Further, it is possible to add decoration such as coloring, embossing, patterning, and edge decoration depending on the use. Furthermore,
Performances such as deodorization, antibacterial deodorization, fragrance, mildew resistance and flame retardancy can be added by known methods.

[0034]

The soundproof material of the present invention is particularly excellent in sound absorption in the high frequency range. Among them, it is excellent in sound absorption in a high frequency region of 500 Hz or higher. In the present invention, sound absorption is compared as a representative value at 2 kHz. The sound absorption coefficient was measured with a sound absorption coefficient measuring device manufactured by Matsushita Intertechno Co., Ltd. at 2 kHz. The two-microphone method is used in principle, but JISA
This is based on the measurement of the normal incidence sound absorption coefficient similar to 1405.

The soundproofing material of the present invention can be applied to a textile product having a light weight, and since it can be well-designed and draped, the soundproofing material can be applied to curtains of homes and public buildings. Can be granted. Also, it can be used as a wallpaper or ceiling material in the same manner. Although flame retardancy is often required for these products, flame retardancy can be easily imparted by using a flame retardant material for the fiber material or performing flame retardant processing.

It can also be used as a part of a floor material and an inner material of a wall. Further, it can be used as a soundproofing interior material for automobiles, ships, and aircraft, and as a part thereof, as a sound absorbing material for audio equipment.

[0037]

【Example】

Example 1 A plain-dyed twill fabric having a basis weight of 50 g / cm ² and a density of 0.5 g / cm ³ made of 100% split fiber Berryma X manufactured by Kanebo Co., Ltd. (a porous layer 1, the number of holes of 2000 μm ² or less is 1,
520 holes, the number of holes of 1000 μm ² or less is 680 holes / c
m ² ), and a printed plain woven fabric having a density of 0.55 g / cm ³ (porous layer ² , the number of pores of 2000 μm ² or less is 1,760
Number, the number of 1000 .mu.m ² below holes 720 / cm ²⁾
A foamed polyethylene (porous layer) having a density of 0.04 g / cm ³ , a thickness of 5 mm, and a basis weight of 21 g / cm ² is sandwiched between and a reaction cross-linkable polyurethane adhesive is applied at an amount of 2 g / cm.
^A curtain, which is the soundproofing material of the present invention, was manufactured by adhering with ² .

The sound absorption coefficients of the porous layers 1 and 2 and the porous layer were 3%, 3% and 38%, respectively. The sound absorption coefficient was 81% when a sound source was placed on the twill fabric (porous layer 1) side of the soundproof material of the present invention in which these were laminated. Also. The sound absorption coefficient when the sound source was placed on the plain fabric side (porous layer 2) was 79%.

Example 2 A polypropylene meltblown nonwoven fabric having a basis weight of 25 g / cm ² and a single fiber diameter of 1 to 5 μm (porous layer, 2000 μm ²
The number of holes below is 2,230, and the number of holes below 1000 μm ² is 830 / cm ² ), and the density is 0.04 g / cm 2.
^3, a thickness of 9 mm, the foamed polyurethane having a basis weight of 36 g / cm ² (porous layer), the curtain is a sound-absorbing fiber products bonded invention in coating weight 2 g / cm ² by using a reactive crosslinkable polyurethane adhesive Manufactured. The sound absorption coefficients of the porous layer and the porous layer alone were 2% and 42%, respectively. The sound absorption coefficient measured by placing a sound source on the porous layer side of the soundproof material of the present invention in which these are laminated was 88%. The sound absorption coefficient measured by placing a sound source on the porous layer side was 42%.

Example 3 In the same manner as in Example 2, the porous layer was mixed with Polyester SD1.4d (Kanebo Co., Ltd.) 1.4d, 51 mm 80% by weight and the heat-sealing fiber Velcombi 2d, 51 mm 20% by weight, carded and laminated. And compression thermoformed with a thickness of 1 cm and a basis weight of 5
00g / cm ² , density 0.05g / cm ³ , sound absorption coefficient 33
%, Only the non-woven fabric was used to produce the soundproof material of the present invention. The sound absorption coefficient of the soundproof material of the present invention was 66%.

Example 4 In the same manner as in Example 2, only the sound absorption coefficient of the porous layer was changed by changing the density, the size of the cells and the basis weight of the foamed polyurethane to produce a soundproof material and measure the sound absorption coefficient. did. The results are shown in Table 1.

[0042]

[Table 1]

Example 5 A soundproof material was produced in the same manner as in Example 2 except that the single fiber diameter of the polypropylene meltblown nonwoven fabric (porous layer) was changed to change the distribution of pores. The sound absorption coefficient was measured and the results are shown in Table 2. The single fiber diameter is an average value measured by taking SEM photographs. The number of holes is the number of holes of 2000 μm ² or less / cm ² .

[0044]

[Table 2]

Example 6 An acrylic resin (acrylonitrile / methyl acrylate = 70: 30 weight ratio) was applied to the surface of the porous layer of Example 3 by spraying to form a porous layer of acrylic resin having a basis weight of 50 g / m ^2. did. In this porous layer, the number of pores of 2000 μm ² or less was 1,210, and the number of pores of 1000 μm ² or less was 530 / cm ² . The sound absorption coefficient of this soundproof material is 8
It was 3%.

Example 7 In the same manner as in Example 2, the commercially available basis weight of the porous layer was 50 g /
m ² , fiber diameter 20 to 30 μ, density 0.05 g / cm
³⁾ A polypropylene spun bond having a thickness of 0.06 mm was used, and two kinds of untreated and sound-proof materials impregnated with a phenol resin emulsion were manufactured in the same manner as in Example 6. The untreated porous layer had 110 pores of 2000 μm ² or less and 8 pores / cm ² of 1000 μm ² or less. The sound absorbing material of this reference example has a sound absorption coefficient of 4
2%. The resin-processed porous layer is 2000μ
The number of holes of m ² or less was 310 and the number of holes of 1000 μm ² or less was 212 / cm ² . The sound absorption coefficient of this soundproof material was 52%.

Example 8 In the same manner as in Example 7, the concentration of the phenol resin emulsion was changed to change the viscosity.
^The sound absorption coefficient was measured by changing the number 1 of the holes of ² or less and the number 2 of the holes of 1000 μm ² or less. Table 3 shows the results. Two
000Myuemu ² The following number of the number of 1000 .mu.m ² or less of the pores of the pores is correlated, and a viscosity of greater many number of 2000 .mu.m ² following holes, reduces the number of 1000 .mu.m ² following hole, 1000 .mu.m ² following The larger the number of holes, the better the sound absorption coefficient.

[0048]

[Table 3]

Claims (3)

[Claims] 1. 200 holes having an area of 2000 μm ² or less
A soundproof material containing a porous layer having a number of pieces / cm ² or more. 2. The soundproof material according to claim 1, wherein the basis weight of the porous layer is 20 g / m ² or more. 3. The soundproof material according to claim 1, wherein the porous layer is near the surface on the sound incident side.