JP5198103B2 - Sound insulation for vehicles - Google Patents

Description

  The present invention relates to a soundproofing material used as a soundproofing material for a vehicle such as an automobile and a weak electric device.

Conventionally, as this type of soundproofing material, a first sound absorbing layer made of urethane foam or the like and a second sound absorbing layer also made of urethane foam or the like are laminated, and a thermoplastic resin film or the like is formed at the interface of these sound absorbing layers. For example, Patent Document 1 discloses a soundproof material having a sound insulation layer interposed therebetween.
When the soundproofing material having such a configuration is used as a soundproofing material for a vehicle, for example, the first sound absorbing layer can absorb the noise outside the vehicle compartment, and the sound insulating layer can block the noise outside the vehicle interior. In addition, the second sound absorbing layer absorbs the noise in the passenger compartment, thereby realizing a quiet passenger compartment.
However, since it has a three-layer structure, it has a disadvantage that the manufacturing method is complicated.

Japanese Patent No. 3718112

  Therefore, an object of the present invention is to realize a soundproofing material having a soundproofing property equivalent to the conventional one with a simple structure.

In order to solve the above-mentioned problems, the present inventors have made extensive studies, and as a result, the sound absorbing layer is composed of a foamed resin sound absorbing layer such as polyurethane foam, and a fiber sound absorbing layer such as felt. The present inventors have found that the above-mentioned problem can be solved by forming a sound insulation layer in which a foamed resin and fibers are combined.
The soundproofing material of the present invention has been made on the basis of such knowledge, and as described in claim 1, the foamed resin-based sound absorbing layer and the fiber-based sound absorbing layer are laminated, and the foamed resin-based sound absorbing material is formed at the interface between these sound absorbing layers. The foamed resin is a polyurethane composed of a polyol compound and an isocyanate compound, with a sound insulation layer having a thickness of 0.8 to 10 mm obtained by combining a resin of the layer and fibers of the fiber-based sound absorption layer, and the polyol compound Is a polyether polyol or polyester polyol.
The soundproofing material according to claim 2 is the soundproofing material according to claim 1, wherein the foamed resin has a foaming speed RT of 15 to 25 seconds.
The soundproof material according to claim 3 is the soundproof material according to claim 1 or 2, wherein the fiber-based sound absorbing layer is felt.
According to a fourth aspect of the present invention, there is provided the soundproofing material according to the third aspect, wherein the felt is a compression press molded felt.
According to a fifth aspect of the present invention, there is provided the soundproofing material according to any one of the first to fourth aspects, wherein the soundproofing material is a soundproofing material for vehicle interior.
In addition, according to the method for producing a soundproof material of the present invention, a foamed resin-based sound absorbing layer and a fiber-based sound absorbing layer are laminated as described in claim 6, and the resin of the foamed resin-based sound absorbing layer is bonded to the interface of these sound absorbing layers. A method for producing a soundproofing material having a sound insulation layer in which fibers of a fiber type sound absorbing layer are combined, in which a fiber type sound absorbing layer is laid in a casting mold, and a foamed resin material is injected on the upper surface side thereof A sound insulation layer having a thickness of 0.8 to 10 mm at the interface between the foamed resin sound absorbing layer and the fiber sound absorbing layer is obtained by impregnating the foamed resin raw material into the fibers of the fiber sound absorbing layer and combining them by foaming. The foamed resin is a polyurethane composed of a polyol compound and an isocyanate compound, and the polyol compound is a polyether polyol or a polyester polyol.

  ADVANTAGE OF THE INVENTION According to this invention, the soundproof material excellent in sound-absorbing property and sound-insulating property is obtained with a simple structure and manufacturing method. In particular, when used as a soundproof material for vehicle interiors, the sound absorption layer made of foamed resin such as polyurethane absorbs noise outside the vehicle compartment, and the sound insulation layer is a composite of foamed resin such as polyurethane and fibers such as felt. The outdoor noise can be insulated, and the noise in the vehicle interior can be absorbed by a sound absorbing layer made of a fiber such as felt to realize a quiet vehicle interior.

  FIG. 1 is a schematic view of the soundproofing material of the present invention. In the figure, reference numeral 10 denotes a soundproofing material. A sound absorbing layer 2 made of a fiber such as felt is laminated on a sound absorbing layer 1 made of a foamed resin such as foamed polyurethane, and the sound absorbing layer 1 has an interface between these sound absorbing layers 1 and 2. A sound insulating layer 3 is formed by combining a foamed resin such as polyurethane and a fiber such as felt of the sound absorbing layer. Specifically, the sound insulating layer 3 is formed by curing a foamed resin in a state where a foamed resin such as urethane resin is impregnated in a fiber such as felt.

As the foamed resin forming the sound absorbing layer 1, foamed polyurethane, foamed polyethylene, foamed polypropylene, or the like can be used.
In particular, the use of polyurethane is preferable from the viewpoint of moldability, and as a polyol compound as a raw material of polyurethane, polyether polyols such as polypropylene glycol, polytetramethylene glycol, and derivatives thereof, condensed polyester polyols, lactone polyester polyols, Examples thereof include polyester polyols such as polycarbonate polyol. In addition, as isocyanate compounds used as raw materials for polyurethane, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (polymeric MDI), tolidine diisocyanate (TODI), naphthalene diisocyanate (NDI), hexamethylene And polyisocyanates such as diisocyanate (HMDI), isophorone diisocyanate (IPDI), and xylylene diisocyanate (XDI). In addition, water is mentioned as a foaming agent. In foaming, trialkylamine such as triethylamine, tetraalkyldiamine such as N, N, N ′, N′-tetramethyl1,3-butanediamine, dibutyltin dilaurate, dibutyltin di (2-ethylhexo). It is preferable to use a catalyst such as an organic tin compound.
In addition, from the viewpoint of forming the sound insulation layer 3, it is preferable to use a foamed resin having a high foaming speed. For example, taking polyurethane as an example, it is preferable to use a urethane resin having an RT (rise time) of about 15 to 25 seconds.

The felt for forming the sound absorbing layer 2 is not particularly limited, but a low-melting polyester, fine cotton polyester, polyester, wool, acrylic, cotton, or other fibers are used alone or in combination to form a felt with a binder fiber as an anti-hair material. Reversible felt felt can be used.
From the viewpoint of forming the sound insulation layer, it is preferable to use felt formed by compression press molding.
Density of compressed felt arbitrariness preferred range of 150~500kg / ^{m 3.}

  The sound insulation layer 3 is preferably formed to a thickness of about 0.05 to 10 mm. This is because if the thickness is less than 0.05 mm, the sound insulation effect is not sufficient, and if it exceeds 10 mm, the weight becomes excessive.

  In order to form the sound insulation layer 3, for example, a compression felt is laid in a casting mold, and a foamed urethane raw material is injected and foamed on the upper surface side thereof, so that the felt is formed at the interface between the urethane foam and the felt. It can be easily formed by impregnating a foamed urethane raw material in the fiber and combining them.

Next, examples of the present invention will be described with reference to comparative examples.
( Reference Example 1 )
Low-melting polyester 25% by weight, polyester 32% by weight, wool 32% by weight, other 15 mm thick repellent felt (1000 g / m ² ) made of acrylic and cotton 11% by weight is adjusted to 40-50 ° C. After setting in the casting mold, polyether polyol as the polyol compound, diphenylmethane diisocyanate (MDI) as the isocyanate compound, and a two-component foamed polyurethane having a reaction rate of RT (sec) of 20 seconds is poured into the casting mold, about 150 It was allowed to stand for 2 seconds to foam urethane and obtain a soundproofing material. As a result, the foamed polyurethane foamed to 10 mm, and a gentle mountain-shaped sound insulation layer of 0.01 to 10 mm was formed in the 15 mm felt.

(Example 2)
Low-melting polyester 25% by weight, polyester 32% by weight, wool 32% by weight, acrylic and cotton 11% by weight of 15mm thick repellent felt (1000g / m ² ) heated in a hot air oven at 195 ° C for 60 seconds Then, this felt was placed in a mold and cold pressed (10 to 15 ° C.) for 60 seconds with a 200 t press machine to obtain a compressed felt having a thickness of 3 mm in the mold. After setting this compression felt into a casting mold whose temperature is adjusted to 40 to 50 ° C., the polyol compound is made of polyether polyol and the isocyanate compound is diphenylmethane diisocyanate (MDI), and the reaction rate is RT (sec) 20 seconds. Two-component foamed polyurethane was poured into a casting mold and allowed to stand for about 150 seconds to foam urethane and obtain a soundproofing material. As a result, the foamed polyurethane foamed to 22 mm, and 0.8 mm of the 3 mm compression felt was formed in the sound insulation layer.

(Example 3)
A soundproof material was obtained in the same manner as in Example 2 except that the diphenylmethane diisocyanate (MDI) was replaced with tolylene diisocyanate (TDI). As a result, the foamed polyurethane foamed to 22 mm, and 0.8 mm of the 3 mm compression felt was formed in the sound insulation layer.

(Comparative Example 1)
When foaming polyurethane, a soundproofing material was obtained in the same manner as in Example 2, except that a polyolefin resin film having a thickness of 50 μm was interposed between the compression felt and the polyurethane.

Next, the sound absorption performance and sound insulation performance of each of the soundproof materials of Reference Example 1, Examples 2 to 3 and Comparative Example 1 were confirmed. The results are shown in FIGS.
The sound absorption performance was measured and evaluated as follows. That is, it evaluated by the measurement of the reverberation room method sound absorption rate based on JIS A1409. However, the volume of the reverberation chamber is 9 m ³ and the sample area is 1 m ² .
The sound insulation performance was measured and evaluated as follows. That is, the sound was emitted vertically toward the surface of the polyurethane layer, and the sound leaked from the surface of the compression felt layer was measured and obtained. However, the measurement result of only the 0.8 mm steel plate was used as a reference, and the evaluation was made based on the difference when the soundproof material was placed on the steel plate.
The measurement results are shown in FIGS.

As is clear from FIGS. 3 and 4, it was confirmed that the soundproofing materials of Examples 2 and 3 can obtain substantially the same sound absorption performance and sound insulation performance as the soundproofing material of Comparative Example 1. That is, it has been confirmed that the soundproofing material of the present invention can provide a soundproofing material having excellent sound absorption performance and sound insulation performance with a simple structure and a simple manufacturing method.
In addition, in the case of the non-compressed felt of Reference Example 1 , since the urethane was cast at one location, the impregnation layer was thickened by increasing the penetration at the casting point, and at a location away from the casting point. Since the impregnation layer becomes thin because of less penetration and the soundproof performance varies depending on the location, it was confirmed that it is desirable to use a compression press molded felt to obtain the soundproof performance as designed.

Schematic diagram of the soundproofing material of the present invention It is a characteristic diagram which shows the sound insulation characteristic of the soundproof material of this invention reference example 1, and the soundproof material of the comparative example 1, (a) shows a sound absorption performance, (b) shows a sound insulation performance. It is a characteristic diagram which shows the soundproofing characteristic of the soundproofing material of Example 2 of this invention, and the soundproofing material of the comparative example 1, (a) shows a sound absorption performance, (b) shows a sound insulation performance. It is a characteristic diagram which shows the soundproofing characteristic of the soundproofing material of Example 3 of this invention, and the soundproofing material of the comparative example 1, (a) shows sound absorption performance, (b) shows sound insulation performance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Foamed resin type sound absorbing layer 2 Fiber type sound absorbing layer 3 Sound insulating layer 10 Sound insulating material

Claims (6)

A sound insulation layer having a thickness of 0.8 to 10 mm in which a foamed resin-based sound absorbing layer and a fiber-based sound absorbing layer are laminated, and the resin of the foamed resin-based sound absorbing layer and the fibers of the fiber-based sound absorbing layer are combined at the interface of these sound absorbing layers. A soundproofing material, wherein the foamed resin is a polyurethane composed of a polyol compound and an isocyanate compound, and the polyol compound is a polyether polyol or a polyester polyol.   The soundproofing material according to claim 1, wherein the foamed resin has a foaming speed RT of 15 to 25 seconds.   The soundproof material according to claim 1 or 2, wherein the fiber-based sound absorbing layer is felt.   The soundproofing material according to claim 3, wherein the felt is a compression press-molded felt.   The soundproof material according to any one of claims 1 to 4, wherein the soundproof material is a soundproof material for vehicle interior. A soundproofing material in which a foamed resin sound absorbing layer and a fiber sound absorbing layer are laminated, and a sound insulating layer in which the resin of the foamed resin sound absorbing layer and the fiber of the fiber sound absorbing layer are combined at the interface of these sound absorbing layers. The fiber-based sound absorbing layer is impregnated into the fiber of the fiber-based sound absorbing layer by laying a fiber-based sound absorbing layer in the casting mold, and injecting the foamed resin material on the upper surface side to cause foaming. These are combined to form a sound insulating layer having a thickness of 0.8 to 10 mm at the interface between the foamed resin sound absorbing layer and the fiber sound absorbing layer, and the foamed resin is a polyurethane composed of a polyol compound and an isocyanate compound. And the polyol compound is a polyether polyol or a polyester polyol.

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