JPH091704A - Noise insulating structure - Google Patents

Abstract

PURPOSE: To provide excellent damping characteristics and to make it possible to control the damping characteristics by using a specified nonwoven fabric made of a polypropylene fiber for one layer constituting a buffer material layer, and positioning this layer between a sheet-shaped noise insulating layer and the lowest layer as the buffer material layer. CONSTITUTION: This noise insulating structure has at least two layers 4A and 4C, wherein the fiber composition of buffer material layers comprising a synthetic fiber is different, and is constituted between a sheet-shaped noise insulating layer and a steel plate 6. The layer 4A constituting the buffer material layer is made of a nonwoven fabric made of polypropylene, which is a super-minute film whose fiber diameter is in the range of 0.1-10×m. Its average apparent density is in the range of 0.02-0.06g/cm<2> , and the thickness is in the range of 5-25mm. Furthermore, the layer 4A is positioned between the sheet-shaped noise insulating layer and the lowest layer 4C, which is the buffer material layer. The control of damping characteristics is performed by changing the fiber diameter, the density and the thickness of the super minute fiber constituting the layer 4A, and it is simple to change the thickness. Furthermore, the layer 4C is constituted of the nonwoven fabric of a polyester fiber having the fiber diameter of 1-50 denier and the average apparent density of 0.01-0.06g/cm<3> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulation structure, and more particularly to a sound insulation structure which is lightweight and has excellent damping characteristics and sound insulation performance.

[0002]

2. Description of the Related Art In recent years, good sound insulation performance and light weight have been demanded for automobile interior materials, particularly floor carpets and dash insulators. Generally, in a floor carpet, as shown in FIG. 1, a carpet skin 1, a latex 2, a backing material 3 (these are collectively referred to as a sheet-like sound insulation layer), a cushioning material layer 4, a mel sheet 5, and a floor panel 6 are laminated in this order. It has a structured structure.

In conventional floor carpets, a felt or urethane foam is used as a cushioning material layer (Japanese Patent Laid-Open No. 31762/1993).
No. 41) is often used. However, these materials have some drawbacks such as sound insulation, light weight, durability and appearance.

Therefore, a cushioning material using a synthetic fiber such as polyester has been proposed (Japanese Patent Laid-Open No. 62-22).
3357, JP-A-4-272263, JP-A-4-185754).

[0005]

A cushioning material made of a thermal bond type synthetic fiber non-woven fabric using a heat-sealing fiber (binder fiber) can be hardened by changing the compounding amount of the binder fiber, the fiber diameter and the apparent density. It is possible to control the height (spring constant). That is, the resonance point can be tuned, and good sound insulation performance can be obtained by shifting the frequency of a large noise input and the resonance point of the sound insulation structure.

However, when a large frequency of noise input is spread over a wide range, it is not sufficient to tune the resonance point alone, and it is necessary to increase the damping of the sound insulation structure. However, under the present circumstances, it is difficult to realize high damping with a cushioning material using a conventional synthetic fiber, urethane foam and felt, and it is difficult to control it.

Therefore, an object of the present invention is to use a cushioning material made of synthetic fiber, which has excellent damping characteristics and which can be suitably used for a floor carpet for vehicles or a dash insulator capable of controlling the damping characteristics. To provide.

[0008]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a buffer material layer made of synthetic fibers has a multi-layer structure, and at least one layer forming the buffer material layer is ultrafine. It was found that a sound insulating structure having excellent damping properties, controllable damping properties, and excellent moldability can be obtained by using a nonwoven fabric made of fibers, and the present invention has been accomplished.

The above object of the present invention is to provide a double-wall type sound insulation structure in which a cushioning material layer made of synthetic fibers has at least two layers having different fiber blends, and is sandwiched between a sheet-like sound insulation layer and a steel plate. In, at least one layer (hereinafter referred to as A layer) constituting the cushioning material layer has an average apparent density of 0.02 to 0.0 made of ultrafine fibers having a fiber diameter of 0.1 to 10 μm.
A polypropylene fiber non-woven fabric having a thickness of 6 g / cm ³ and a thickness of 5 to 25 mm, wherein the layer A is located between the sheet-like sound insulation layer and the bottom layer which is a cushioning material layer. It was achieved by the sound insulation structure.

Hereinafter, the present invention will be described in more detail. The most characteristic feature of the present invention is that, in a cushioning material made of synthetic fibers having at least two layers having different fiber blends, at least one layer constituting the cushioning material layer is a nonwoven fabric made of ultrafine fibers. In this case, the ultrafine fibers can be produced by appropriately selecting them from known methods, but it is particularly preferable to produce them by the melt blow method.

The resonance point of the conventional cushioning material using synthetic fiber, urethane foam and felt is in the road noise region (20).
It exists in the vicinity of 0 to 500 Hz), and it is expected to improve damping to improve the sound insulation performance in this region, but it is difficult to realize high damping with these cushioning materials, and its control is also difficult. The current situation is that it is difficult.

On the other hand, the ultrafine fibers are very excellent in damping characteristics, and are expected to have better sound insulation performance near the resonance point as compared with conventional synthetic fibers, urethane foams and felts.

However, when ultrafine fibers are used alone, they still have problems such as lack of cushioning property and difficulty in molding. In the present invention, the above problem is solved by laminating a polyester fiber non-woven fabric excellent in cushioning property and moldability and a microfiber non-woven fabric excellent in damping property to form a cushioning material having a multilayer structure.

An outline of the constitution of the present invention is shown in FIGS.
The configurations shown in FIGS. 2 and 3 are examples, and the present invention is not limited thereto.

In the present invention, the non-woven fabric constituting the layer A is made of ultrafine fibers, and polypropylene is preferable as the material of the fibers because of its cost and ease of manufacture. Further, the non-woven fabric constituting the B layer and the C layer is preferably made of polyester fiber, judging from cost, moldability, durability, stability of performance after processing and the like.

In the present invention, the layer A is preferably composed of a non-woven fabric composed of ultrafine fibers having a fiber diameter of 0.1 to 10 μm obtained by the melt blown manufacturing method.
When the fiber diameter is less than 0.1 μm, it is difficult to obtain fibers having that diameter and it is difficult to obtain rigidity as a cushioning material. When the fiber diameter exceeds 10 μm, high damping due to the ultrafine fibers cannot be expected.

The average apparent density of the layer A is 0.02 to 0.0.
It is preferably in the range of 6 g / cm ³ . When the average apparent density is less than 0.02 g / cm ³ , the cushioning property is extremely deteriorated, and even if the layers B and C are hardened, they will sink when loaded. On the other hand, if it exceeds 0.06 g / cm ³ , the sound insulation performance, the riding comfort and the like are deteriorated, and the followability during molding is deteriorated. Average apparent density is 0.03-0.05g / cm
The range of ³ is more preferable.

The thickness of layer A is preferably in the range of 5 to 25 mm. If the thickness is less than 5 mm, the effect of the ultrafine fiber non-woven fabric is small and the damping cannot be improved. Conversely, if the thickness exceeds 25 mm, the cushioning property of the cushioning material layer as a whole deteriorates. Further, as described above, it is difficult to form an ultrafine fiber non-woven fabric, and in the present invention, B
Formability of the cushioning material layer is ensured by the other layers such as the layer and the C layer. Therefore, if the A layer is too thick, the formability of the entire cushioning material layer is lowered. The thickness of layer A is more preferably in the range of 10 to 20 mm.

In the present invention, the control of the damping characteristics is performed by changing the fiber diameter, density and thickness of the above ultrafine fibers, but the control by the thickness is particularly simple.

In the present invention, the A layer is the lowermost layer (C layer) which is a sheet-like sound insulation layer and a cushioning material layer as shown in FIG.
Or between the uppermost layer (B layer) and the lowermost layer (C layer), which are cushioning material layers, as shown in FIG. 3, for example. The formability of the cushioning material layer is ensured by the sheet-shaped sound insulation layer and the C layer in the former case, and by the sheet-shaped sound insulation layer and the B layer and the C layer in the latter case.

On the other hand, it is difficult to bond the polyester fiber or the thermoplastic resin used for the sheet-like sound insulation layer and the polypropylene ultrafine fiber to each other. Due to the bonding between the layers, as shown in FIG. Bottom layer (C layer) [see FIG. 4 (A)] that is a sound insulation layer and a cushioning material layer, or the topmost layer (B layer) and bottom layer (C layer) that is a cushioning material layer [FIG. 4]
It is preferable that there is a portion where [see (B)] is joined.

In the present invention, the non-woven fabrics constituting the B layer and the C layer are made of polyester fibers having a fiber diameter in the range of 1 to 50 denier and have an average apparent density of 0.01.
It is preferably in the range of 0.06 g / cm ³ . If the fiber diameter is less than 1 denier, it may be difficult to obtain appropriate cushioning properties, durability may be reduced, spinning speed may be significantly reduced, and card passing properties may be poor and the quality of the nonwoven fabric may be deteriorated. On the other hand, if it exceeds 50 denier, the non-woven fabric becomes too hard, so that not only adequate cushioning properties cannot be obtained, but also sound and vibration performance such as sound absorbing performance deteriorates. If the average apparent density is less than 0.01 g / cm ³ , the cushioning property and durability are significantly reduced, and conversely, if it exceeds 0.06 g / cm ³ , the nonwoven fabric becomes too hard and appropriate cushioning properties cannot be obtained. Not only that, it is against the demand for weight reduction.

In the present invention, the non-woven fabric constituting the B layer and the C layer is composed of at least two kinds of polyester fibers,
The fiber 1 is in the range of 60 to 95% by weight of polyethylene terephthalate fiber, and the fiber 2 has a melting point of the sheath portion which is 1 to that of the fiber 1.
The polyester fiber having a core-sheath structure which is a copolymerized polyester having a low temperature of 00 ° C. or higher is preferably in the range of 5 to 40% by weight.

By using polyethylene terephthalate fiber as the fiber 1, it is possible to secure a difference in melting point from the binder fiber and widen the melting point range of the binder fiber that can be selected. Further, in order to obtain good moldability, cushioning properties and durability, it is more preferable to use side-by-side type conjugate type fibers.

The fiber 2 functions as a binder fiber.
The melting point of the sheath portion of the fiber 2 is lower than that of the fiber 100 by 100 ° C. or more, because if the difference in melting point is less than 100 ° C., it will overlap with the melting point of the ultrafine fibers made of polypropylene constituting the A layer. This is because the temperature conditions during molding become stricter. In some cases, the ultrafine fibers may melt and the expected performance may not be obtained.

The melting point difference is not particularly limited because it is not too large and causes no problem. However, if the difference is 150 ° C. or more, the melting point of the fiber 2 is too low and handling becomes difficult. The material of the core of the fiber 2 is not particularly limited, but polyethylene terephthalate fiber is particularly preferably used in order to make it easily function as the binder fiber.

60 to 95% by weight of fiber 1 and 5 to 5 of fiber 2
The reason for setting it to 40% by weight is as follows. Fiber 1 is 60
If the amount of the fiber 2 is less than 40% by weight, and the amount of the fiber 2 exceeds 40% by weight, the amount of the binder fiber is too large, resulting in deterioration of durability and deterioration of cushioning property. On the contrary, when the fiber 1 exceeds 95% by weight, the fiber 2
Is less than 5% by weight, the amount of the binder fiber is too small and the moldability is lowered, and the bonding between the respective layers of the cushioning material layer is weakened.

When the sound insulation structure of the present invention is laid on a floor panel of a vehicle and used as a floor carpet,
The fiber diameter of the fiber 1 is in the range of 10 to 40 denier, the fiber diameter of the fiber 2 is in the range of 1 to 15 denier, and the average apparent density of the nonwoven fabric is in the range of 0.02 to 0.04 g / cm ^3. More preferable.

When the fiber diameter of the fiber 1 is less than 10 denier, the durability and lightness required for the floor carpet cannot be achieved at the same time, and when it exceeds 40 denier, the spring constant of the entire cushioning material layer increases. The sound insulation performance deteriorates, and the number of fibers contained per unit volume decreases, so that the durability also decreases.

When the fiber diameter of the fiber 2 is less than 1 denier, the spinning speed may be significantly reduced, and the card passing property may be poor, and the quality of the nonwoven fabric may be deteriorated. On the other hand, when it exceeds 15 denier, the number of fibers contained per unit volume decreases, so that the bonding points decrease and the durability and moldability decrease.

If the average apparent density of the non-woven fabrics constituting the layers B and C is less than 0.02 g / cm ³ , sufficient durability, cushioning property and moldability as a carpet cannot be obtained, and conversely 0.04 g / cm ³ If it exceeds ³ cm ³ , the cushioning material layer becomes too hard, and it is difficult to obtain the appropriate cushioning properties required for a carpet, which is also against the weight reduction.

When non-woven fabric is used for the cushioning material layer, pressing and trimming of unnecessary portions are required. At this time, a high-density portion is generated near the end portion of the cushioning material layer and the trimming portion, but the above-mentioned regulation regarding the density is not naturally applied to this portion.

[0033]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto.

Examples 1 to 9 assume the case where the sound insulation structure of the present invention is used for a floor insulator,
The structure is based on FIG. 2 or FIG.

Example 1 As the carpet surface 1, a carpet having a pile surface density of 580 g / m ² which is generally used for automobiles, such as a needle punched carpet or a tufted carpet, was used. 2 is latex. The backing material 3 has an areal density of 600 g /
A m ² PE sheet was used. The carpet 1, the latex 2, and the backing material 3 were obtained in the pre-bonded state and used. 4 is a cushioning material layer, and the mel sheet 5 is a sheet made of asphalt having a thickness of 2.5 mm (area density of 4.0 Kg / m ² ), and a thickness of 0.8 mm (area density of 6.3 Kg / m ² ). The floor panel 6 is heat-sealed.

The cushioning material layer 4 has a three-layer structure as shown in FIG. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.04, which are obtained by the melt-blowing method.
An ultrafine fiber non-woven fabric made of polypropylene with g / cm ³ was used. For the layers B and C, a polyester non-woven fabric having a thickness of 10 mm and an average apparent density of 0.03 g / cm ³ was used. As the fiber composition of polyester non-woven fabric, 80% of 6 denier x 51 mm hollow conjugate type,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 20%.

The laminated body in which the respective layers A, B and C were stacked was heated in an oven until the internal temperature reached 140 ° C., and then formed into a thickness of 30 mm by a pressing machine. The backing material 3 and the cushioning material layer 4 are bonded to each other with a backing material 13
The mixture was preliminarily melted at 0 ° C., and the molded cushioning material was placed thereon, pressed, cooled, and adhered. FIG. 4B shows a cross section of the end of the sound insulation structure after molding.

Generally, a bead shape is applied to a floor panel for automobiles to obtain rigidity, and there are irregularities for passing a heater duct, a wire harness, etc. It remained flat. It goes without saying that this embodiment can be processed along the shape of the floor panel by giving the shape of the press machine a shape.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. All of the performances were equal or higher. It was confirmed. Table 2 shows the results.

Example 2 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 15 mm, and an average apparent density of 0.04, which are obtained by the melt-blowing method.
An ultrafine fiber non-woven fabric made of polypropylene with g / cm ³ was used. A non-woven fabric made of polyester having an average apparent density of 0.03 g / cm ^{3 having} a thickness of 5 mm was used for the B layer and a thickness of 10 mm was used for the C layer. As the fiber composition of the polyester nonwoven fabric, the hollow conjugate type of 6 denier × 51 mm was 80%, and the core / sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the comparative example. All of the performances were equal or higher. It was confirmed. Table 2 shows the results.

Example 3 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The buffer material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 20 mm, and an average apparent density of 0.04 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a polyester non-woven fabric having a thickness of 5 mm and an average apparent density of 0.03 g / cm ³ was used. As the fiber composition of polyester non-woven fabric, 80% of 6 denier x 51 mm hollow conjugate type,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a packing material.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. In all the performances, equivalent or higher performance was obtained. It was confirmed. Table 2 shows the results.

Example 4 Carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6 were the same as in Example 1.

The buffer material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.05 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a polyester non-woven fabric having an average apparent density of 0.03 g / cm ^{3 having} a thickness of 10 mm was used. As the fiber composition of polyester non-woven fabric, 80% of 6 denier x 51 mm hollow conjugate type,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the comparative example. In all the properties, the same or higher performance was obtained. It was confirmed. Table 2 shows the results.

Example 5 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.03 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a polyester non-woven fabric having an average apparent density of 0.03 g / cm ^{3 having} a thickness of 10 mm was used. As the fiber composition of polyester non-woven fabric, 80% of 6 denier x 51 mm hollow conjugate type,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. In all the performances, equivalent or higher performance was obtained. It was confirmed. Table 2 shows the results.

Example 6 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The buffer material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.04 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a non-woven fabric made of polyester having a thickness of 10 mm and an average apparent density of 0.02 g / cm ³ was used. As the fiber composition of the polyester non-woven fabric, the hollow conjugate type of 13 denier x 51 mm is 90
%, 2 denier × 51 mm core-sheath type binder fiber (sheath part melting point 110 ° C.) was set to 10%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. In all the properties, the same or higher performance was obtained. It was confirmed. Table 2 shows the results.

Example 7 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a two-layer structure as in FIG. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.04 g / obtained by the melt-blowing method.
A non-woven fabric made of polypropylene and having an ultrafine fiber size of ³ cm ³ was used. C layer has an average apparent density of 0.03 g with a thickness of 20 mm
A non-woven fabric of polyester / cm ³ was used. 6 denier x 51 m as the fiber mixture of polyester non-woven fabric
80% of hollow conjugate type of m, 2 denier ×
51 mm core-sheath type binder fiber (sheath melting point 11
(0 ° C.) was set to 20%. Molded in the same manner as in Example 1 (thickness 3
0 mm) and adhered to the backing material. A cross section of the end portion of the sound insulation structure after molding is shown in FIG.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. In all of the performances, equivalent or higher performance was obtained. It was confirmed. Table 2 shows the results.

Example 8 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 had a two-layer structure as in Example 7. The layer A has an average fiber diameter of 3 μm, a thickness of 25 mm, and an average apparent density of 0.04 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. The C layer has an average apparent density of 0.04 g with a thickness of 5 mm.
A non-woven fabric of polyester / cm ³ was used. 6 denier x 51 m as the fiber mixture of polyester non-woven fabric
80% of hollow conjugate type of m, 2 denier ×
51 mm core-sheath type binder fiber (sheath melting point 11
(0 ° C.) was set to 20%. Molded in the same manner as in Example 1 (thickness 3
0 mm) and adhered to the backing material.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. All of the performances were equal or higher. It was confirmed. Table 2 shows the results.

Example 9 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a two-layer structure as in the seventh embodiment.
did. The average fiber obtained by the melt blown manufacturing method in the A layer
Fiber diameter 3 μm, thickness 5 mm, average apparent density 0.04 g /
cm ^ThreeUsing polypropylene ultrafine fiber non-woven fabric
Was. The C layer has a thickness of 25 mm and an average apparent density of 0.03 g.
/ Cm^ThreeThe polyester non-woven fabric of was used. Pollies
6 denier x 51 m as the fiber composition of the tel non-woven fabric
80% of hollow conjugate type of m, 2 denier ×
51 mm core-sheath type binder fiber (sheath melting point 11
(0 ° C.) was set to 20%. Molded in the same manner as in Example 1 (thickness 3
0 mm) and adhered to the backing material.

The sound transmission loss, cushioning property, durability and moldability of the sample obtained by the above method were evaluated and compared with the comparative example. It was confirmed. Table 2 shows the results.

Comparative Examples 1 to 11 assume floor insulators. Comparative Example 1 In Comparative Example 1, urethane foam was used as the cushioning material layer. Urethane foam was prepared by the following method. Liquid A consisting of 100 parts of propylene oxide 1,2,6-hexanetriol as a polyol, 2 parts of water, 1 part of a surfactant and 0.5 part of carbon black as a polyol in an injection foaming mold having a clearance of 30 mm. The solution B consisting of 100 parts of tolylene diisocyanate and 0.5 part of silicone oil was injected into the polyol at a low pressure of 1.25 times equivalent amount of isocyanate to foam. The obtained urethane foam sheet has a thickness of 30 mm and an apparent density of 0.06 g / cm ^3.
Met. For the adhesion between the buffer material layer 4 and the backing material 3, a spray type adhesive material was applied and adhered.

The carpet skin 1, latex 2, mel sheet 5, and floor panel 6 used were the same as in Example 1. The backing material 3 has an EV with an areal density of 1.5 kg / m ² .
A sheet made of A was used. The sound transmission loss, cushioning property and durability of the sample obtained by the above method were evaluated and compared with the examples.

Comparative Example 2 In Comparative Example 2, a felt (trade name: Feltop manufactured by Towa Textile Co., thickness: 30 mm, apparent density: 0.06 g / cm ³ ) was used as a buffer layer. The backing material and the cushioning material layer were adhered by preliminarily making the backing material in a molten state at 130 ° C., placing the cushioning material layer on the backing material, and then pressing and cooling to bond them.

The carpet skin 1, latex 2, mel sheet 5, and floor panel 6 used were the same as in Example 1. The backing material 3 has an EV with an areal density of 1.5 kg / m ² .
A sheet made of A was used.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property and durability,
It compared with the Example.

Comparative Example 3 Carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6 were the same as in Example 1.

For the cushioning layer 4, a non-woven fabric made of polyester having a thickness of 30 mm and an average apparent density of 0.03 g / cm ³ was used. As the fiber composition of the polyester non-woven fabric, a hollow conjugate type of 6 denier x 51 mm is 80
%, 2 denier × 51 mm core-sheath type binder fiber (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with Examples and Comparative Examples 1 and 2. For Comparative Examples 1 and 2, the same or higher performance was obtained for all performances, but it was confirmed that the sound insulation performance was inferior to the Examples. Table 2 shows the results.

Comparative Example 4 Carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6 were the same as in Example 1.

For the cushioning material layer 4, a polyester non-woven fabric having a thickness of 30 mm and an average apparent density of 0.02 g / cm ³ was used. As the fiber composition of polyester non-woven fabric, 13
90 denier x 51 mm hollow conjugate type
%, 2 denier × 51 mm core-sheath type binder fiber (sheath part melting point 110 ° C.) was set to 10%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with Examples and Comparative Examples 1 and 2. For Comparative Examples 1 and 2, the same or higher performance was obtained for all performances, but it was confirmed that the sound insulation performance was inferior to the Examples. Table 2 shows the results.

Comparative Example 5 Carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6 were the same as those used in Example 1.

For the cushioning material layer 4, a polyester ultrafine fiber non-woven fabric having an average fiber diameter of 3 μm, a thickness of 30 mm and an average apparent density of 0.04 g / cm ³ obtained by a melt-blowing method was used.

Adhesion with a backing material was performed in the same manner as in Example 1, but the peel strength was lower than in Example and there was a practical problem. Further, although the sound insulation performance was very excellent, the cushioning property, the durability and the moldability were inferior to those of the examples. Table 2 shows the results.

Comparative Example 6 Carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6 were the same as in Example 1.

The cushioning material layer 4 had a two-layer structure as in Example 7. The layer A has an average fiber diameter of 3 μm, a thickness of 35 mm, and an average apparent density of 0.04 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. The C layer has an average apparent density of 0.04 g with a thickness of 5 mm.
A non-woven fabric of polyester / cm ³ was used. 6 denier x 51 m as the fiber mixture of polyester non-woven fabric
80% of hollow conjugate type of m, 2 denier ×
51 mm core-sheath type binder fiber (sheath melting point 11
(0 ° C.) was set to 20%. Molded in the same manner as in Example 1 (thickness 4
0 mm) and adhered to the backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the examples. Sound insulation performance is excellent,
The cushioning property, the durability and the moldability were inferior, and the cushioning property and the moldability were at a level that was not practical. Table 2 shows the results.

Comparative Example 7 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a three-layer structure as in the first embodiment.
did. The average fiber obtained by the melt blown manufacturing method in the A layer
Fiber diameter 3 μm, thickness 2 mm, average apparent density 0.05 g /
cm ^ThreeUsing polypropylene ultrafine fiber non-woven fabric
Was. 15 mm thick average apparent density for B and C layers
0.03g / cm^ThreeMade of polyester non-woven fabric
Was. As a fiber blend of polyester non-woven fabric, 6 denier
80% of hollow conjugate type of 50 mm x 51 mm,
2 denier x 51 mm core-sheath type binder fiber
(Sheath part melting point 110 ° C.) was set to 20%. Same as Example 1
Molded to a thickness of 32 mm and adhered to the backing material.
Was.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability and compared with the examples. Although it was confirmed that the sound insulation performance was improved as compared with Comparative Examples 1 to 3, the effect of the ultrafine fibers was smaller than that of the Examples. Table 2 shows the results.

Comparative Example 8 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 had a three-layer structure as in Example 1. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.01 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a polyester non-woven fabric having an average apparent density of 0.03 g / cm ^{3 having} a thickness of 10 mm was used. As the fiber composition of polyester non-woven fabric, 80% of 6 denier x 51 mm hollow conjugate type,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the examples. The sound insulation performance and the moldability were at the same level as those of the examples, but the cushioning property and the durability were remarkably lowered. Table 2 shows the results.

Comparative Example 9 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.08 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a polyester non-woven fabric having an average apparent density of 0.03 g / cm ^{3 having} a thickness of 10 mm was used. As the fiber composition of polyester non-woven fabric, 80% of 6 denier x 51 mm hollow conjugate type,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the examples. A decrease in performance other than durability was observed as compared with the examples. Table 2 shows the results.

Comparative Example 10 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The cushioning material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.04 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a non-woven fabric made of polyester having a thickness of 10 mm and an average apparent density of 0.005 g / cm ³ was used. As the fiber composition of the polyester non-woven fabric, the hollow conjugate type of 13 denier x 51 mm is 80
%, 2 denier × 51 mm core-sheath type binder fiber (sheath part melting point 110 ° C.) was set to 20%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the examples. A reduction in cushioning property and durability was observed as compared with the examples. Table 2 shows the results.

Comparative Example 11 As the carpet skin 1, latex 2, backing material 3, mel sheet 5, and floor panel 6, the same materials as in Example 1 were used.

The buffer material layer 4 has a three-layer structure as in the first embodiment. The layer A has an average fiber diameter of 3 μm, a thickness of 10 mm, and an average apparent density of 0.04 g obtained by the melt-blowing method.
/ I was used cm ³ of polypropylene microfiber nonwoven fabric. For the layers B and C, a polyester non-woven fabric having a thickness of 10 mm and an average apparent density of 0.08 g / cm ³ was used. As the fiber composition of the polyester non-woven fabric, 90% of hollow conjugate type of 6 denier x 51 mm,
A core-sheath type binder fiber of 2 denier × 51 mm (sheath part melting point 110 ° C.) was set to 10%. It was molded (thickness: 30 mm) in the same manner as in Example 1 and adhered to a backing material.

The samples obtained by the above method were evaluated for sound transmission loss, cushioning property, durability and moldability, and compared with the examples. The sound insulation performance and the cushioning property were lower than those of the examples. Table 2 shows the results.

[0096]

[Table 1]

[0097]

[Table 2]

[0098]

Since the sound insulation structure of the present invention has the above-mentioned structure, it has the following effects. (1) Since damping can be improved as compared with the case where a conventional synthetic fiber, urethane foam or felt is used as a cushioning material, the sound insulation performance can be improved especially in the road noise region. (2) It is possible to easily control the damping characteristic, which was difficult when the conventional synthetic fiber, urethane foam or felt was used as the cushioning material. (3) Despite using a non-woven fabric made of ultrafine fibers,
Good cushioning properties, durability and formability are obtained.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of an automobile floor carpet.

FIG. 2 is a diagram showing a configuration example (in the case of two layers) of the present invention.

FIG. 3 is a diagram showing a configuration example (in the case of three layers) of the present invention.

FIG. 4 is a diagram showing a state of a molding end portion of the present invention.

[Explanation of symbols]

 1 Carpet skin 2 Latex 3 Backing material 4 Buffer material layer (A layer, B layer, C layer) 5 Mel sheet 6 Floor panel

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G10K 11/178 G10K 11/16 H

Claims (7)

[Claims] 1. A double-wall type sound-insulating structure in which a shock-absorbing layer made of synthetic fibers has at least two layers having different fiber blends, and is sandwiched between a sheet-like sound-insulating layer and a steel plate. Of at least one layer (hereinafter referred to as A layer) constituting the composition has an average apparent density of ultrafine fibers having a fiber diameter of 0.1 to 10 μm in the range of 0.02 to 0.06 g / cm ³ and a thickness of 5 to 25 mm. The sound insulating structure is characterized in that the layer A is located between the sheet-like sound insulating layer and the bottom layer which is the cushioning material layer. 2. A top layer (hereinafter B) in which layer A is a cushioning material layer.
The sound insulation structure according to claim 1, wherein the sound insulation structure is located between a layer) and a lowermost layer (hereinafter C layer). 3. At the molded end of the sound insulation structure, a sheet-like sound insulation layer and a bottom layer (C layer) which is a cushioning material layer and / or a top layer (B layer) and a bottom layer (C layer) which are cushioning material layers. 3. The sound insulation structure according to claim 1, wherein there is a portion adjacent to and joined to each other. 4. The non-woven fabric having an average apparent density of 0.01 to 0.06 g / cm ^{3 in which} the B and C layers are made of polyester fibers having a fiber diameter in the range of 1 to 50 denier. The sound insulation structure according to claim 3, which is characterized in that. 5. The non-woven fabric constituting the B layer and the C layer is composed of at least two kinds of polyester fibers, the fiber 1 is in the range of 60 to 95% by weight of polyethylene terephthalate fiber, and the fiber 2 has a melting point of the sheath portion of the fiber 1. The sound insulation structure according to claim 4, wherein the polyester fiber having a core-sheath structure which is a copolyester having a temperature lower than 100 ° C. is in the range of 5 to 40% by weight. 6. The sound insulation structure according to claim 4, wherein among the at least two types of polyester fibers of the non-woven fabric forming the B layer and the C layer, the fiber 1 is a side-by-side conjugate type. 7. The sheet-like sound insulation layer is composed of at least a carpet skin and a backing material made of a thermoplastic resin laminated on the back surface of the carpet skin, and is laid on a floor panel of a vehicle. The sound insulation structure according to claim 4.