JP2005338223A - Waterproof sound absorbing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waterproof sound absorbing material that never decreases in sound absorptivity even if a porous substance layer gets wet with water, and can effectively absorb noise in a wide band of not only a frequency range below 150 Hz, but also a high frequency range exceeding 150 Hz and improve the degree of freedom of a product type. <P>SOLUTION: The waterproof sound absorbing material has a foamed substance layer 1 which is arranged on a sound source side and the porus substance layer 2 laminated on a rigid-wall 3 side of the foamed substance layer 1. The porous substance layer 2 is formed of a water-repellent porous substance, concretely, glass wool with water-repellency (floating wool formed by sticking cloth made waterproof on one surface of glass wool made water-repellent), etc. The foamed substance layer 1 is formed of a foamed body consisting of respective components of 1st diol of 500 to 5,000 in molecular weight, 2nd diol of ≤500 in molecular weight, an inorganic filler, water as a foaming agent, and isocyanate as raw material components. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water- and sound-absorbing material, and more particularly to a water- and sound-absorbing material that can effectively absorb wide-band noise not only in a low frequency region of 150 Hz or less but also in a high frequency region exceeding 150 Hz and improve the degree of freedom of the product form. About.

  Conventionally, as this type of water- and sound-absorbing material, (a) one using a porous body layer made of glass wool, rock wool or the like, (b) one provided with an air layer on the sound source side, (c) An air layer is provided on the sound source side, and (d) a structure in which at least two or more layers of high-density and low-density fiber assemblies with different air permeability of 5 to 100 times are laminated (for example, Patent Document 1).

  However, in the water-resistant sound-absorbing material of (a) and (b), in order to exert a required sound-absorbing effect against noise with a frequency band exceeding 500 Hz or noise of 500 Hz or less, The wall thickness has to be increased, and as a result, the overall weight of the water-resistant sound-absorbing material is increased. In addition, the water-resistant sound absorbing material (c) has a problem that an air layer exists on the sound source side of the water-resistant sound absorbing material, so that the weight of the water-resistant sound absorbing material becomes heavy and a large space must be taken. On the other hand, the water-resistant sound-absorbing material (d) uses a viscous resistance of air, and by laminating fiber assemblies having different densities on a porous sound-absorbing structure that absorbs sound by converting sound wave energy into heat energy. The high-density part is an additional mass, and the low-density part plays the role of a spring, so that a so-called dynamic vibration absorber is constructed to improve the sound absorption coefficient particularly in the low frequency band. However, there is a problem that a sufficient sound absorption effect cannot be obtained particularly in a so-called low frequency band of 100 Hz or less. In addition, sound and vibration in the low frequency band generate not only air-borne sound but also shakiness of buildings and windows, so it is necessary to take measures against solid-borne sound and vibration prevention at the same time. Then, the countermeasure was difficult.

  For this reason, the present applicant first uses a viscous resistance of air, converts sound wave energy into heat energy, absorbs sound, and further absorbs a sound-absorbing sound-absorbing structure in which fiber assemblies having different densities are laminated. A material has been developed and applied (Japanese Patent Laid-Open No. 2003-316364).

  The water-absorbing sound-absorbing material includes a foam layer disposed on the sound source side and a porous body layer laminated on the rigid wall side of the foam layer. Here, the foam layer is formed of a foam containing a first diol having a molecular weight of 500 to 5000, a second diol having a molecular weight of 500 or less, an inorganic filler, water as a foaming agent, and isocyanate. Moreover, the porous body layer is formed of general-purpose glass wool.

  According to the water-absorbing sound-absorbing material having such a configuration, it is possible to configure a so-called dynamic vibration absorber in which the high-density portion plays the role of additional mass and the low-density portion plays the role of a spring, thereby improving the sound absorption coefficient particularly in the low frequency band. it can.

  However, the water-resistant and sound-absorbing material having such a configuration has the following drawbacks.

  First, since the glass wool constituting the porous body layer is exposed, there is a problem that when such glass wool gets wet with water, the sound absorption characteristics, particularly the sound absorption characteristics in the low frequency region are deteriorated.

  Secondly, the glass wool constituting the porous body layer has a drawback that the sound absorption effect is weakened in a high frequency region of 150 Hz or higher, or in a low frequency region of 150 Hz or lower.

  Thirdly, since the foam layer and the porous body layer are integrally molded and a surface film is formed on the sound source side of the foam layer during the integral molding, there is a difficulty that the degree of freedom of the product cannot be improved. there were. In other words, since the surface film is formed at the same time when the foam layer and the porous body layer are integrally formed, in order to exhibit the required sound absorption characteristics, the sound source side of the foam layer and the rigidity of the porous body layer are required. There was the difficulty that the wall side had to be changed.

JP-A-8-152890 JP 2003-316364 A

  In the present invention, even if the glass wool constituting the porous body layer is wetted with water, there is no risk that the sound absorption characteristics in the low frequency region will deteriorate, and not only in the low frequency region of 150 Hz or less but also in the high frequency region exceeding 150 Hz. An object of the present invention is to provide a water- and sound-absorbing material capable of effectively absorbing noise and improving the degree of freedom of product form.

  The water-resistant sound-absorbing material according to the first aspect of the present invention includes a foam layer disposed on the sound source side, and a porous body layer laminated on the rigid wall side of the foam layer. It consists of a water repellent porous body.

  The water-resistant sound absorbing material according to the second aspect of the present invention includes a foam layer disposed on the sound source side, a first porous body layer laminated on the sound source side of the foam layer, and a rigid wall of the foam layer A second porous body layer laminated on the side, and the first and second porous body layers are made of a water-repellent porous body.

  The water-resistant sound-absorbing material according to the third aspect of the present invention includes a foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and a sound source of the foam layer. The second porous body layer is made of a water-repellent porous body. The second porous body layer is formed on the side surface and has a coating surface on which a large number of holes are provided on the sound source side.

  The water-resistant sound absorbing material according to the fourth aspect of the present invention includes a foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and a sound source of the foam layer. The second porous body layer is formed of a water-repellent porous body. The second porous body layer is formed on the side surface and has a coating surface that is roughened on the sound source side by friction processing.

  The water-resistant sound-absorbing material according to the fifth aspect of the present invention includes a foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and a sound source of the foam layer The second porous body layer is made of a water-repellent porous body.

  The water-resistant sound absorbing material according to the sixth aspect of the present invention includes a foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and a sound source of the foam layer. The second porous body layer is made of a water repellent porous body.

  The water-resistant sound absorbing material according to the seventh aspect of the present invention includes a foam layer disposed on the sound source side, a first porous body layer laminated on the sound source side of the foam layer, and a rigid wall of the foam layer A second porous body layer laminated on the side, and a damping material layer disposed on the rigid wall side of the second porous body layer, wherein the first and second porous body layers are made of a repellent material. It consists of an aqueous porous body.

  The water-absorbing sound-absorbing material according to the eighth aspect of the present invention includes a foam layer disposed on the sound source side, a first porous body layer laminated on the sound source side of the foam layer, and a rigid wall of the foam layer The second porous body layer laminated on the side, the damping material layer arranged on the rigid wall side of the second porous body layer, and the second porous body layer and the damping material layer. The first and second porous body layers are made of a water-repellent porous body.

  According to a ninth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to eighth aspects, at least one of the first porous body layer and the second porous body layer is The material is made of water-repellent glass wool, rock wool, coarse wool felt, vegetable fiber felt, animal fiber felt, synthetic fiber felt or a mixture thereof.

  According to a tenth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to ninth aspects, the foam layer is a first diol having a molecular weight of 500 to 5000, a first diol having a molecular weight of 500 or less. 2 diols, inorganic fillers, water as a foaming agent, and isocyanate components are used as raw material components.

An eleventh aspect of the present invention is the water-absorbing sound-absorbing material according to any one of the first to tenth aspects, wherein the density of the foam is 50 to 500 kg / m ³ .

  According to a twelfth aspect of the present invention, in the water-resistant sound absorbing material according to any one of the first to eleventh aspects, the hydroxyl group content contained in the first diol and the hydroxyl group content contained in the second diol The ratio is 1: 0.3 to 2.5.

  According to a thirteenth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to twelfth aspects, the content of the inorganic filler is 10 to 200 with respect to 100 parts by weight of the first diol. Parts by weight.

  According to a fourteenth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to thirteenth aspects, the content of water as a foaming agent is 2 with respect to 100 parts by weight of the first diol. -5 parts by weight.

  According to a fifteenth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to fourteenth aspects, the sum of the hydroxyl contents of the first and second diols and water as the blowing agent The isocyanate index (NCO / OH), which is the ratio of the isocyanate content to the isocyanate content, is in the range of 0.5 to 1.0.

  According to a sixteenth aspect of the present invention, in the water-resistant sound absorbing material according to any one of the first to fifteenth aspects, the isocyanate index is in the range of 0.6 to 0.9.

  According to a seventeenth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to sixteenth aspects, the first diol is a polyester polyol, a polyether polyol, a polybutadiene polyol, a polyisoprene polyol, It is made of any diol selected from polyolefin polyol, polyacrylate polyol and polycarbonate polyol.

  According to an eighteenth aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the first to seventeenth aspects, the second diol is ethylene glycol, propylene glycol, butanediol, hexanediol, or octanediol. And diol selected from aliphatic type such as decanediol or aromatic type such as N, N-bis (2-hydroxypropyl) aniline.

  A nineteenth aspect of the present invention is the water-resistant sound absorbing material according to any one of the first to eighteenth aspects, wherein the inorganic filler is carbon black, silica, calcium carbonate, mica, talc, magnesium oxide, It is made of any inorganic filler selected from aluminum oxide, magnesium hydroxide, and aluminum hydroxide.

  According to a twentieth aspect of the present invention, in the water-resistant sound absorbing material according to any one of the first to nineteenth aspects, the isocyanate is 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4 , 4′diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude tolylene diisocyanate, crude diphenylmethane diisocyanate, p-phenylene diisocyanate, p-xylene diisocyanate, tetramethylene-1,4-diisocyanate. Is.

  According to a twenty-first aspect of the present invention, in the water-absorbing sound-absorbing material according to any one of the ninth to twentieth aspects, the constraining material layer is composed of a member having a large Young's modulus.

  According to a twenty-second aspect of the present invention, in the water- and sound-absorbing material according to any one of the ninth to twenty-first aspects, the constraining material layer is made of a metal material.

  According to a twenty-third aspect of the present invention, in the water-resistant sound absorbing material according to any one of the ninth to twenty-second aspects, the thickness of the constraining material layer is 0.1 to 2 mm. .

  According to the water-absorbing and sound-absorbing material of the first aspect to the twenty-third aspect of the present invention, the following effects are obtained.

  First, since the porous body layer is made of water-repellent glass wool, even if the porous body layer is wetted with water, there is no possibility that the sound absorption characteristics in the low frequency region will deteriorate.

  Secondly, by providing a porous body layer on both sides of the foam layer, the sound absorption characteristics in a high frequency region of 150 Hz or higher can be improved, and as a result, a water- and sound-absorbing material that can be used in a wide frequency range can be provided. .

  Third, by providing a hole or the like with a needle-like member in the surface film of the water-resistant sound-absorbing material, the air permeability of the foam layer can be improved, and consequently the sound absorption characteristics in the low frequency region can be improved.

  Fourthly, the degree of freedom of the product form can be improved by adhering / contacting a coating layer formed separately to the sound source side of the foam layer.

Embodiments to which the water-resistant sound absorbing material of the present invention is applied will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 is a cross-sectional view showing a first embodiment of a water- and sound-absorbing material in the present invention.

  In the same figure, the water-resistant sound absorbing material of the present invention includes a foam layer 1 disposed on the sound source side and a porous body layer 2 laminated on the rigid wall 3 side of the foam layer 1.

  The porous body layer 2 is formed of a water-repellent porous body, specifically, glass wool having water repellency. As the glass wool having such water repellency, floating wool manufactured by Nippon Sheet Glass Amenity Co., Ltd., which is formed by bonding a water-resistant cloth to one side of a water-resistant glass wool, can be used.

  The water-repellent porous body as the porous body layer 2 is made of water-repellent rock wool, coarse wool felt, vegetable fiber felt, animal fiber felt, synthetic fiber felt or a mixture thereof. May be formed.

The porous body layer 2 may be formed with a loss coefficient η of 0.05 or more, an air permeability of 0.1 dm ³ / s or more, and a thickness of 1 to 50 mm, preferably 10 to 25 mm. As described later, the porous body layer 2 having such a configuration has excellent sound absorption characteristics over a wide range from a low frequency region to a high frequency region, and is also effective in reducing solid propagation sound and vibration. Demonstrate vibration damping. Furthermore, the porous body layer 2 is formed of a material having a thermal conductivity of 0.1 to 0.5 W / mK, or a base material made of urethane foam or a urethane foam base material blended with a thermal conductivity imparting material. Also good. Here, as the thermal conductivity imparting material, one selected from those composed of ceramics or metal materials, silicon carbide powder, alumina powder, aluminum powder, graphite, copper powder, stainless steel powder or 2 A mixture of at least seeds or graphite (the amount of graphite added is 10 to 150 parts by weight with respect to 100 parts by weight of the polyol forming the urethane foam) is used.

  The porous body layer 2 having such a structure is attached to a sound source such as an engine and has sound absorption performance effective for reducing air-borne sound, solid-borne sound and vibration generated from the engine. Even if the temperature in the room or the soundproof box rises due to the above operation, the temperature rise of the porous body can be suppressed, the deterioration is not promoted, and the life is prolonged.

  Next, as the foam layer 1, a foam having open cell foaming is used. This is because when the sound wave enters the foam layer 1, the air in the gap portion vibrates, the sound wave energy is converted into heat energy by the viscous resistance of the air, and the sound absorption is performed. This is because the foam layer 1 itself vibrates and the sound wave energy is converted into heat energy by the viscous resistance at this time, and sound absorption is performed. In addition, the porous body layer 2 is laminated on one side of the foam layer 1 because the foam layer 1 part acts as an additional mass, that is, a weight, and the porous body layer part is a spring, that is, an air spring. This is because it acts as a role and performs sound absorption by membrane vibration.

  Such a foam layer 1 is formed of the following foam.

  First, the foam is composed of a first diol having a molecular weight of 500 to 5000, a second diol having a molecular weight of 500 or less, an inorganic filler, water as a foaming agent, and an isocyanate component. By making the first diol, which is the main polymer, a diol having a molecular weight of 500 to 5000, and preferably a molecular weight of 1000 to 2000, it is possible to obtain a foam with added vibration damping properties. Here, when the main polymer is composed of a diol having a molecular weight of less than 500, a hard foam is obtained and vibration damping properties cannot be obtained. On the other hand, when the molecular weight is composed of a diol having a molecular weight exceeding 5000, the initial viscosity is increased and the required foaming is achieved. The body cannot be obtained. When a polyol other than triol or the diol used in the present invention is used as the main polymer, it is difficult to obtain vibration damping properties.

Second, the density of the foam is preferably in the range of 50 to 500 kg / m ³ . Density becomes too Good ventilation is less than 50 kg / m ^3, the low-frequency range sound absorbing efficiency is deteriorated, 500 kg / m ³ becomes too poor ventilation as opposed to more than the sound is reflected difficulty absorbing Because it becomes.

  Thirdly, as the first diol constituting the foam, polyester polyol, polyether polyol, polybutadiene polyol, polyisoprene polyol, polyolefin polyol, polyacrylic ester polyol, polycarbonate polyol and the like are suitable.

  Fourth, the second diol constituting the foam is used as a chain extender of the foam layer 1 of the present invention and plays a role of reinforcement. Here, the reason why the molecular weight is 500 or less is that if the molecular weight exceeds 500, the reinforcing effect cannot be obtained. Further, when this component is a polyol other than triol or diol used in the present invention, the reinforcing effect becomes too great and the vibration damping property is impaired.

  Fifth, the second diol constituting the foam may be an aliphatic group such as ethylene glycol, propylene glycol, butanediol, hexanediol, octanediol, decanediol, or N, N-bis (2-hydroxypropyl). Aromatic diols such as aniline are preferred.

  Here, the ratio of the hydroxyl group content contained in the first diol used in the foam and the hydroxyl group content contained in the second diol is preferably 1: 0.3 to 2.5. This is because if the ratio of the hydroxyl group content of the second diol is less than 0.3, the reinforcing effect becomes insufficient, and even if the ratio of the hydroxyl group content exceeds 2.5, no difference in effect is observed.

  Sixth, the inorganic filler constituting the foam is used for the purpose of reinforcing the foam layer and adding damping properties. This inorganic filler is preferably blended in an amount of 10 to 200 parts by weight per 100 parts by weight of the first diol having a molecular weight of 500 to 5000. If the amount is less than 10 parts by weight, the effect of adding sufficient reinforcement and vibration damping is small, and if it exceeds 200 parts by weight, the viscosity of the composition before molding becomes high and molding becomes difficult.

  Seventh, as the inorganic filler constituting the foam, carbon black, silica, calcium carbonate, mica, talc, magnesium oxide, aluminum oxide, magnesium hydroxide, aluminum hydroxide and the like are suitable.

  Eighth, water constituting the foam is used as a foaming agent. Although the addition amount of a foaming agent should just be the quantity from which a foam is obtained, 2-5 weight part is suitable with respect to 100 weight part of 1st diols with a molecular weight of 500-5000. This is because if the amount is less than 2 parts by weight, sufficient foaming is not performed, and if the amount exceeds 5 parts by weight, no significant difference in effect is observed.

  Ninthly, as the isocyanate constituting the foam, basically those used for the production of urethane foam can be used, and in particular, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude tolylene diisocyanate, crude diphenylmethane diisocyanate, p-phenylene diisocyanate, p-xylene diisocyanate, tetramethylene-1,4-diisocyanate and the like are suitable. Can be used as a mixture.

  Tenth, in order to impart moderate rigidity and vibration damping to the foam, the ratio of the total hydroxyl group content of the first diol, the second diol, and water as the blowing agent to the isocyanate content of the isocyanate It is desirable that the isocyanate index (NCO / OH) is in the range of 0.5 to 1.0, preferably 0.6 to 0.9. This is because if the isocyanate index is less than 0.5, the degree of cross-linking decreases and rigidity decreases, and if it exceeds 1.0, moderate rigidity is obtained, but vibration damping performance decreases.

  11thly, you may add suitably the catalyst used for manufacture of a normal urethane foam layer, a foaming agent, a flame retardant, a plasticizer, a coloring agent, etc. to said foam according to the objective.

  According to such a water-absorbing and sound-absorbing material of the first embodiment, the water-repellent glass wool constituting the porous body layer 2 has a significantly lower water absorption rate than ordinary glass wool. Even if it gets wet with water, the sound absorption characteristic in the low frequency region does not deteriorate, and the original sound absorption function can be maintained.

According to such a water-absorbing and sound-absorbing material of the first embodiment, the water-repellent glass wool constituting the porous body layer 2 has a significantly lower water absorption rate than ordinary glass wool. Even if it gets wet with water, the sound absorption characteristic in the low frequency region does not deteriorate, and the original sound absorption function can be maintained.
[Second Embodiment]
FIG. 2 is a cross-sectional view showing a first embodiment of the water- and sound-absorbing material in the present invention. In the figure, parts common to those in FIG. 1 are denoted by the same reference numerals and detailed description thereof is omitted.

  2, the water-resistant sound-absorbing material of the present invention includes a foam layer 1 disposed on the sound source side, a first porous body layer 2 a laminated on the sound source side of the foam layer 1, and the foam layer 1. And a second porous body layer 2b laminated on the rigid wall 3 side. Here, the first and second porous body layers 2a and 2b are laminated on both surfaces of the foam layer 1 in the same manner as described above, because the foam layer 1 portion acts as an additional mass, that is, a role of a weight. This is because the first and second porous body layers 2a and 2b act as a spring, that is, an air spring, and perform sound absorption by membrane vibration.

  The first and second porous body layers 2a and 2b have the same configuration, and are formed in the same manner as the porous body layer 2 described above.

FIG. 3 shows the sound absorption characteristics of the water-resistant sound-absorbing material in the second embodiment. Here, in the figure, the thick line L1 is the sound absorption characteristic of the conventional sound absorbing material in which the thickness of the porous body layer is 100 mm, and the thin line L2 is the thickness of the first porous body layer 2a of 25 mm, the second The sound absorption characteristics of the water-resistant sound absorbing material of the present invention in which the thickness of the porous body layer 2b is 75 mm, the dotted line L3 is the sound absorption characteristics of a conventional sound absorbing material in which the porous body layer is made of glass wool and the thickness is 100 mm. Show. From the figure, it can be seen that the water-absorbing and sound-absorbing material of the present invention exhibits excellent sound absorption characteristics not only in a low frequency region of 150 Hz or less but also in a high frequency region of 150 Hz or more. Therefore, if the water- and sound-absorbing material in the first embodiment is used, it is possible to provide a water- and sound-absorbing material that can cope with a wide frequency range.
[Third Embodiment]
FIG. 4 is a cross-sectional view showing a third embodiment of the water-resistant and sound-absorbing material in the present invention. In the figure, parts common to those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

  4, the water-resistant sound absorbing material of the present invention includes a foam layer 1 disposed on the sound source side, a second porous body layer 2b laminated on the rigid wall 3 side of the foam layer 1, and a foam layer. 1 and a coating surface 5 formed on the side surface of the sound source.

  Here, a large number of holes (not shown) are provided on the sound source side of the coating surface 5 in a direction perpendicular to the coating surface 5 by a needle-like member.

  By forming such holes in the coating surface 5, the air permeability of the coating surface 5 is improved, and as a result, the peak frequency of the sound absorption coefficient can be moved to the low frequency side.

FIG. 5 shows the sound absorption characteristics of the water-resistant sound-absorbing material in the third embodiment. Here, in the figure, the thin line L4 is a sound absorption characteristic of a conventional sound absorbing material having no holes on the coating surface 5, and the dotted line L5 is a hole on the sound source side of the coating surface 5 with 50 holes per cm ² by a needle-like member. The sound absorption characteristic of the formed first water-resistant sound absorbing material of the present invention, the thick line L6 is the second water-resistant sound absorbing material of the present invention in which 200 holes per 1 cm ² are formed on the sound source side of the coating surface 5 by a needle-like member. This shows the sound absorption characteristics. From the figure, it can be seen that the peak frequency of the sound absorption rate in the first and second water-resistant sound absorbing materials of the present invention moves to the low frequency side. Therefore, if the water-absorbing and sound-absorbing material in the second embodiment is used, it is possible to provide a water- and sound-absorbing material that can cope with a low frequency region of 150 Hz or less. In addition, it replaces with formation of the hole by such a needle-like member, and there exists an effect similar to the above-mentioned water-proof sound-absorbing material, even if it subjects the coating surface 5 to friction processing by the grinder and roughens the said surface.
[Fourth Embodiment]
FIG. 6 is a cross-sectional view showing a fourth embodiment of the water-resistant and sound-absorbing material in the present invention. In the figure, parts common to those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 6, the water-resistant sound-absorbing material 1 includes a foam layer 1 arranged on the sound source side, a second porous body layer 2 b laminated on the rigid wall side of the foam layer 1, and a sound source of the foam layer 1. And a coating layer 6 bonded to the side.

  Here, the coating layer 6 is formed separately from the integral molding of the foam layer 1 and the second porous body layer 2b. This is to improve the degree of freedom of the product form.

FIG. 7 shows the sound absorption characteristics of the water-resistant sound absorbing material in the fourth embodiment. Here, the thick line L7 in the figure represents the sound absorption of the conventional first sound absorbing material in which the porous body layer 4 made of glass wool has a thickness of 50 mm and the coating layer is integrally formed on the sound source side of the foam layer 1. Characteristics, one-dot chain line L8 is a sound absorption characteristic of a conventional second sound-absorbing material in which the thickness of the porous body layer 4 made of glass wool is 100 mm and a coating layer is integrally formed on the sound source side of the foam layer 1, a thin line L9 is a sound absorption characteristic of the first water-resistant sound absorbing material of the present invention, in which the porous layer 4 made of glass wool has a thickness of 50 mm, and a separate coating layer 6 is adhered to the sound source side of the foam layer 1; A dotted line L10 indicates the sound absorption characteristics of the second water-resistant sound absorbing material of the present invention in which the porous body layer 4 made of glass wool has a thickness of 50 mm and a separate coating layer 6 is adhered to the sound source side of the foam layer 1 Is shown. From the figure, it can be seen that the first and second water-resistant sound-absorbing materials of the present invention exhibit the same sound-absorbing characteristics as the conventional first and second sound-absorbing materials. Therefore, if the water-resistant sound absorbing material in the fourth embodiment is used, a separate coating layer 6 is bonded to the sound source side or the rigid wall side of the foam layer 1 according to the required sound absorption characteristics and construction method. This can be dealt with by contact (contact), and as a result, the degree of freedom of the product form can be improved. In addition, the coating layer 6 is not limited to what was adhere | attached on the foam layer 1, You may make the coating layer 6 contact | abut (contact) the foam layer 1. FIG.
[Fifth Embodiment]
FIG. 8 is a sectional view showing a fifth embodiment of the water- and sound-absorbing material in the present invention. In the figure, parts common to those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 8, the water-resistant sound absorbing material of the present invention includes a foam layer 1 disposed on the sound source side, a first porous body layer 2 a laminated on the sound source side of the foam layer 1, and the foam layer 1. A second porous body layer 2b stacked on the rigid wall 4 side and a vibration damping material layer 7 disposed on the rigid wall side of the second porous body layer 2b are provided.

  The damping material layer 7 in the present invention is not particularly limited as long as the object can be achieved. For example, the damping material layer 7 is a foam made of a viscoelastic body having open cells inside, and the viscoelastic foam is a sound source. The one in which the foam density distribution is adjusted so that the foam density increases or decreases as it approaches the side is used. Here, as the viscoelastic foam, a plurality of viscoelastic foams, each having a different foam density, are laminated so that the foam density is larger or smaller as the sound source side is approached, In addition, as the foaming density of the viscoelastic foam, it is a high density or low density on the sound source side, and thirdly, a laminate of a damping sheet made of a viscoelastic body on the sound source side of the viscoelastic foam, Fourthly, a laminate of a closed cell foam made of a viscoelastic body on the sound source side of the viscoelastic foam, fifth, a laminate of a metal thin film layer on the sound source side of the viscoelastic foam, sixth, A laminate of a damping sheet made of a viscoelastic material on the rigid wall side of the viscoelastic foam is used.

When the damping material layer 7 having such a configuration is arranged, the effect of further reducing vibration and solid-propagating sound is increased.
[Sixth Embodiment]
FIG. 9 is a cross-sectional view showing a sixth embodiment of the water-resistant and sound-absorbing material in the present invention. In the figure, parts common to those in FIGS. 1, 2 and 8 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 9, the water-absorbent sound-absorbing material of the present invention includes a foam layer 1 disposed on the sound source side, a first porous body layer 2 a laminated on the sound source side of the foam layer 1, and the foam layer 1. The second porous body layer 2b laminated on the rigid wall 3 side, the damping material layer 7 disposed on the rigid wall 4 side of the second porous body layer 2b, and the second porous body layer 2b And a restraining material layer 8 disposed between the damping material layers 7.

  The constraining material layer 8 in the present invention is composed of the following.

  First, it is preferable to use a material having a Young's modulus larger than that of the damping material layer 7 as the restraining material layer 8.

  Secondly, a material made effective of the sound absorption effect of the foam layer 1 and suitable for the purpose as the constraining material layer 8 is a metal material, specifically, a punching metal made of aluminum or stainless steel. Or a nonwoven fabric made of aluminum fibers is suitable.

  Third, the thickness of the constraining material layer is preferably 0.1 to 2 mm. This is because if the thickness is less than 0.1 mm, the intended effect cannot be obtained, and even if the thickness exceeds 2 mm, no difference is seen in the effect. Note that the foam layer 2 on the sound source side also has the coating surface 6 in the present embodiment.

  If the water-resistant sound absorbing material having such a configuration is used, the vibration damping effect can be further improved.

  In the first to sixth embodiments described above, the foam layer 1 is described as a single foam layer having a uniform foam density. First, a foam having open cells inside, in which a thin film layer is integrally formed with the foam on the surface on the sound source side, and second, a thin film layer having a thickness of 1 mm or less, for example, One that is integrally molded with the foam on both the side and the rigid wall side, third, the foam density of the open-cell foam is different in the thickness direction, and fourth, the plurality of different foams The open cell foam is laminated so that the foam density is inclined, fifth, the foam density of the open cell foam is high on the sound source side, sixth, You may use what consists of a viscoelastic body as an open-cell foam.

  Further, instead of the above-described vibration damping material layer, the following configuration, for example, a viscoelastic body coated fiber is applied to the surface of each fiber to form a viscoelastic body coated fiber, and each viscoelastic body coated fiber is assembled. A fibrous aggregate having a sound-absorbing effect may be used. Here, the fibrous aggregate is one in which the fiber density distribution is adjusted so that the fiber density increases or decreases with increasing distance from the brother 1 toward the sound source side, and secondly, a plurality of fibers each having a different fiber density. The fibrous aggregate is laminated so that the fiber density is increased or decreased as it approaches the sound source side. Third, the fiber density of the fibrous assembly is high or low on the sound source side. Fourthly, a vibration damping sheet made of viscoelastic material is laminated on the sound source side of the fibrous assembly, and fifth, closed cell foam made of viscoelastic material on the sound source side of the fibrous assembly. A laminated body, sixth a laminated metal thin film layer on the sound source side of the fibrous aggregate, and seventh a laminated damping sheet made of a viscoelastic body on the rigid wall side of the fibrous aggregate. Things may be used.

Sectional drawing which shows 1st Embodiment of the water-proof sound-absorbing material in this invention. Sectional drawing which shows 2nd Embodiment of the water-proof sound-absorbing material in this invention. Explanatory drawing which shows the sound absorption characteristic of the water-resistant sound-absorbing material which concerns on the 2nd Embodiment of this invention. Sectional drawing which shows 3rd Embodiment of the water-proof sound-absorbing material in this invention. Explanatory drawing which shows the sound absorption characteristic of the water-resistant sound-absorbing material which concerns on the 3rd Embodiment of this invention. Sectional drawing which shows 4th Embodiment of the water-proof sound-absorbing material in this invention. Explanatory drawing which shows the sound absorption characteristic of the water-resistant sound-absorbing material which concerns on the 4th Embodiment of this invention. Sectional drawing which shows 5th Embodiment of the water-proof sound-absorbing material in this invention. Sectional drawing which shows 6th Embodiment of the water-proof sound-absorbing material in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Water-resistant sound-absorbing material 1 ... Foam layer 2 ... Porous body layer 2a ... 1st porous body layer 2b ... 2nd porous body layer 3 ... Rigid wall 5 ... Coating surface 6 ... Coating layer 7 ... Damping material layer 8 ... Restraint material layer

Claims (23)

A foam layer disposed on the sound source side, and a porous body layer laminated on the rigid wall side of the foam layer;
The water-sound-absorbing material, wherein the porous body layer is made of a water-repellent porous body. A foam layer disposed on the sound source side, a first porous body layer laminated on the sound source side of the foam layer, and a second porous body layer laminated on the rigid wall side of the foam layer And
The water and sound-absorbing material, wherein the first and second porous body layers are made of a water-repellent porous body. A foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and formed on the sound source side surface of the foam layer, A coating surface provided with holes,
The water-absorbing sound-absorbing material, wherein the second porous body layer is made of a water-repellent porous body. Formed on the sound source side of the foam layer, the second porous body layer laminated on the rigid wall side of the foam layer, and the sound source side surface of the foam layer, and the own sound source side is friction processed And a coating surface roughened by
The water-absorbing sound-absorbing material, wherein the second porous body layer is made of a water-repellent porous body. A foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and a coating layer bonded to the sound source side of the foam layer,
The water-absorbing sound-absorbing material, wherein the second porous body layer is made of a water-repellent porous body. A foam layer disposed on the sound source side, a second porous body layer laminated on the rigid wall side of the foam layer, and a coating layer in contact with the sound source side of the foam layer,
The water-absorbing sound-absorbing material, wherein the second porous body layer is made of a water-repellent porous body. A foam layer disposed on the sound source side, a first porous body layer laminated on the sound source side of the foam layer, and a second porous body layer laminated on the rigid wall side of the foam layer And a damping material layer disposed on the rigid wall side of the second porous body layer,
The water and sound-absorbing material, wherein the first and second porous body layers are made of a water-repellent porous body. A foam layer disposed on the sound source side, a first porous body layer laminated on the sound source side of the foam layer, and a second porous body layer laminated on the rigid wall side of the foam layer And a damping material layer disposed on the rigid wall side of the second porous body layer, and a constraining material layer disposed between the second porous body layer and the damping material layer,
The water and sound-absorbing material, wherein the first and second porous body layers are made of a water-repellent porous body.   At least one of the first porous body layer and the second porous body layer is made of water-repellent glass wool, rock wool, coarse wool felt, vegetable fiber felt, animal fiber felt, or synthetic fiber. The water-absorbent sound-absorbing material according to any one of claims 1 to 8, wherein the water-absorbent sound-absorbing material comprises any one of felts or a mixture thereof.   The foam layer is composed of a first diol having a molecular weight of 500 to 5000, a second diol having a molecular weight of 500 or less, an inorganic filler, water as a foaming agent, and isocyanate components as raw material components. The water-absorbing sound-absorbing material according to any one of claims 1 to 9. 11. The water-absorbing sound-absorbing material according to claim 1, wherein the foam has a density of 50 to 500 kg / m ³ .   12. The ratio of the hydroxyl group content contained in the first diol and the hydroxyl group content contained in the second diol is 1: 0.3 to 2.5. The water-resistant sound-absorbing material according to claim 1.   The water-sound-absorbing material according to any one of claims 1 to 12, wherein the content of the inorganic filler is 10 to 200 parts by weight with respect to 100 parts by weight of the first diol.   The water-resistant sound-absorbing material according to any one of claims 1 to 13, wherein a content of water as the foaming agent is 2 to 5 parts by weight with respect to 100 parts by weight of the first diol.   The isocyanate index (NCO / OH), which is the ratio of the total hydroxyl content of the first and second diols and water as a blowing agent to the isocyanate content of the isocyanate, is in the range of 0.5 to 1.0. The water-absorbing and sound-absorbing material according to any one of claims 1 to 14, wherein   16. The water-absorbing and sound-absorbing material according to claim 1, wherein the isocyanate index is in a range of 0.6 to 0.9.   The first diol is any one selected from a polyester polyol, a polyether polyol, a polybutadiene polyol, a polyisoprene polyol, a polyolefin polyol, a polyacrylate polyol, and a polycarbonate polyol. The water-resistant sound-absorbing material according to any one of claims 1 to 16.   The second diol is selected from aliphatic systems such as ethylene glycol, propylene glycol, butanediol, hexanediol, octanediol and decanediol, or aromatic systems such as N, N-bis (2-hydroxypropyl) aniline. The water- and sound-absorbing material according to any one of claims 1 to 17, wherein the diol is any one of selected diols.   The inorganic filler is any inorganic filler selected from carbon black, silica, calcium carbonate, mica, talc, magnesium oxide, aluminum oxide, magnesium hydroxide, and aluminum hydroxide. The water-resistant sound-absorbing material according to any one of claims 1 to 18.   The isocyanate is 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4 ′ diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude tolylene diisocyanate, crude diphenylmethane diisocyanate, p-phenylene diisocyanate, p-xylene diisocyanate. 20. The water-absorbent sound-absorbing material according to claim 1, wherein the water-absorbent material is any one of isocyanates selected from tetramethylene-1,4-diisocyanate.   21. The water-absorbing and sound-absorbing material according to claim 9, wherein the constraining material layer is composed of a member having a large Young's modulus.   The water-resistant and sound-absorbing material according to any one of claims 9 to 21, wherein the constraining material layer is made of a metal material. The water-resistant sound-absorbing material according to any one of claims 9 to 22, wherein the constraining material layer has a thickness of 0.1 to 2 mm.

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