JPH10236205A - Floor insulator for automobile, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a floor insulator for automobile of double wall type suitable for a floor insulator carpet for automobile, and its manufacturing method. SOLUTION: In a sound insulating structure of double wall type, a buffer material layer to constitute the sound insulating structure comprises at least two layers (hard layer and soft layer) of different density, the soft layer is installed so as to be located on a vehicle body panel side, the buffer material layer is made of the fiber aggregate in the range of 2-20 denier in mean fiber diameter and 20-100mm in mean fiber length, mainly consisting of the synthetic fiber, and the surface density of the whole buffer material layer is in the range of 400-2000g/m<2> .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-wall type automobile floor insulator suitable for an automobile floor insulator carpet and a method of manufacturing the same.

[0002]

2. Description of the Related Art A floor insulator carpet for an automobile generally has a carpet skin layer 1, as shown in FIG.
The backing layer 2, the cushioning material layer 3, and the mel sheet layer 4 are configured to be sequentially laminated on the floor panel 5. The floor insulator carpet for an automobile is a sound insulation structure having a double wall structure in which a cushioning material layer (soft layer) 3 is inserted between a carpet skin layer 1 and a melsheet layer 4 or a floor panel 5.

[0003] Conventional floor carpets often use felt as a cushioning material layer. However, since the felt has poor adhesion to the floor panel (mel sheet) due to poor shapeability, the sound insulation performance is generally inferior. In addition, irregularities due to the laid wire harness or the like may not be absorbed, and irregularities may occur on the carpet skin, which may cause inconvenient appearance. Furthermore, the defibrated fibers lack natural quality and thus lack stability in quality. In addition, there is a disadvantage that the weakness between the fibers causes an economic sag.

In order to improve such a defect, a cushioning material using a urethane foam has been proposed as a cushioning material in place of felt (Japanese Patent Laid-Open No. 3-176241).
By shaping this urethane foam and using it as a cushioning material, the adhesion between the cushioning material and the floor panel is improved, and not only the sound insulation performance is improved, but also the carpet skin becomes even and flat, so the appearance is excellent. In addition, it has the effect of preventing aging and instability of quality.

However, when a urethane foam is used as a cushioning material, the material cost is high, and in addition to a carpet molding step, a liquid polyol and isocyanate injection step, a foaming step, and an adhesive step are required. Therefore, there is a drawback that the process requires time and a large-scale facility including an exhaust facility is required, resulting in poor productivity. In addition, since the urethane foam has a higher spring constant and a higher resonance point than felt having the same thickness, FIG.
As shown in (2), the vibration isolating region above the resonance point is narrowed, and the overall value of the transmission loss is inferior.

In order to solve the above problems (1)
Proposals have been made to improve the material of the buffer material layer and (2) to increase the number of the buffer material layers. Regarding (1), it has been proposed to use a nonwoven fabric capable of being shaped by mixing a heat-adhesive fiber with a synthetic fiber such as polyester for the cushioning material layer (JP-A-62-223357, JP-A-Hei. 4-272263
No.). On the other hand, as for (2), a structure in which a buffer material layer has a multilayer structure (provided with a different hardness layer) has been proposed in order to improve sound absorption performance such as improvement of sound absorption performance and resonance point tuning. JP-A-61-70085,
JP-A-3-233).

[0007]

In order to obtain a buffer material layer using both (1) and (2), that is, a multi-layered synthetic fibrous buffer material layer, (a) pressing a soft layer and a hard layer A method of obtaining a buffer material layer having a different hardness layer by obtaining them separately by molding and laminating them using an adhesive or the like, and (b) a method of obtaining a buffer material layer having a different density layer by simultaneous simultaneous press molding. There are two possibilities.

However, in the method (a), the number of steps is increased and the cost is increased. On the other hand, when the method (b) is used for the fiber compound found in the conventional proposal, the soft layer becomes more compressed and harder than the hard layer, and the hardness of each layer becomes closer. A cushioned material layer cannot be obtained.

Accordingly, an object of the present invention is to provide a double-walled sound insulation structure in which a cushioning material layer having at least two different hardness layers (hard layer-soft layer) constituting the sound insulation structure is simultaneously pressed integrally. An object of the present invention is to provide a floor insulator for a vehicle, which is obtained by molding, and a method for manufacturing the same.

[0010]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
In a double-wall type sound insulation structure, the cushioning material layer constituting the sound insulation structure is composed of at least two different density layers (hard layer-soft layer), and the soft layer is located on the vehicle body panel side. And the buffer layer is composed of synthetic fibers as a main component and has an average fiber diameter of 2 to 20 deniers and an average fiber length of 20.
A floor aggregate for an automobile, wherein the fiber aggregate is in the range of 100 to 100 mm, and the areal density of the entire cushioning material layer is in the range of 400 to 2000 g / m ² , and at least two density layers are provided. The present invention has been attained by a method of manufacturing a floor insulator for an automobile, wherein the cushioning material layer is simultaneously obtained by integral press molding.

Hereinafter, the present invention will be described in more detail. Important points in the present invention are that (1) the buffer layer constituting the sound insulating structure has at least two different density layers (hard layer-soft layer), and the buffer layer (soft layer) is vibrated. Is located on the partition wall side, such as a floor panel where noise and noise enter,
(2) A buffer material layer having at least two different density layers can be obtained by simultaneous and integral pressure molding. (3) In the fiber aggregate constituting the buffer material layer, the thickest fiber layer has an average fiber diameter of 2 The fiber having a softening point of at least 20 ° C. lower than that of the above-mentioned fiber and having an average fiber diameter of 1.5 to 10 denier (fiber B) has a fiber content of 5 to 20% by weight. 40% by weight, at least one of the other fiber layers has a fiber density of 2 to 13 denier (fiber A) of 80 to 95% by weight, and a fiber having a softening point lower than that of the fiber by at least 20 ° C. This is achieved by the fact that 1.5 to 10 denier fiber (fiber B) is composed of 5 to 20% by weight.

First, the different density layers (1) will be described. Generally, when a buffer material having a uniform hardness is used, the resonance point f ₀ in the sound transmission loss is one. In order to effectively use the vibration isolation and sound insulation areas (√2f ₀ or more), it is desired to shift the resonance point f ₀ to the lower frequency side.

To shift the resonance point to the lower frequency side, it is possible to cope with this by increasing the mass between the carpet skin and the backing layer and reducing the spring of the cushioning material layer. However, an increase in mass not only causes an increase in cost but also contradicts a demand for a lighter vehicle. On the other hand, if the cushioning material layer is made to have a low spring, the sink of the carpet will increase, and sufficient cushioning properties cannot be obtained.

Such a problem can be solved by adopting the configuration of the present invention. The performance of the floor insulator can be estimated by measuring the sound absorption coefficient and the vibration transmissibility of the fiber material layer. In order to improve the performance, it is necessary to increase these two performances.

First, regarding the effect of the sound absorption coefficient, in order to improve the sound insulation performance, the higher the sound absorption coefficient of the fiber material layer, the better. The sound absorption coefficient is determined due to various factors such as the surface density and the average diameter of the fiber material layer, and increasing the surface density or reducing the average diameter of the fibers mixed in the fiber assembly is
This is a very effective means for improving the sound absorption coefficient. However, increasing the density adds weight and increases the cost of the material.

Next, regarding the effect of the vibration transmissibility, the smaller the vibration transmissibility of the fiber assembly, the greater the effect on the sound insulation performance. Here, the vibration transmissibility greatly depends on the dynamic spring constant of the object, and it is necessary to reduce the dynamic spring constant in order to improve the sound insulation performance. Therefore, in order to improve the sound insulation performance of the floor insulator, it is ideal that the fiber assembly layer has a high sound absorption coefficient and a low spring constant. However, both performances are generally contradictory and it is difficult to improve both. Was.

Therefore, the present inventors succeeded in improving both contradictory performances by forming the sound absorbing material layer into a laminated structure of at least two layers and distributing the above performance to each layer. Specifically, the thickest layer in the fiber assembly layer is a layer for securing a sound absorption coefficient, and the other layers are layers for reducing a spring constant.

Next, the method (2) for producing the automobile floor insulator of the present invention will be described. BACKGROUND ART A floor insulator carpet for an automobile is required to have a formability adapted to complicated irregularities due to a bead shape of a floor panel, a laid wire harness, a heater duct, and the like. Therefore, when a nonwoven fabric made of synthetic fiber is used for the cushioning material layer, it is necessary to mix a thermoadhesive fiber or an adhesive in order to enable shaping.

In order to obtain a buffer material layer having at least two layers of different hardness (hard layer-soft layer), (a) the soft layer and the hard layer are separately formed by pressing, and this is formed using an adhesive or the like. Two methods are conceivable: a laminating method, and (b) a method of obtaining a different hardness layer (hard layer-soft layer) by simultaneous integral press molding. Both the method (a) and the method (b) are the steps in the case where thermoplastic thermoadhesive fibers are mixed into the nonwoven fabric. First, the nonwoven fabric is put into a mold and heated to fuse the thermoadhesive fibers. This is cooled and molded while being pressed.

In the method (a), the number of steps is increased and the cost is increased. Therefore, it is desirable to use the method (b).
In the method (b), a nonwoven fabric corresponding to a soft layer and a nonwoven fabric corresponding to a hard layer are laminated, then put into a mold, heated, pressed, and cooled. The nonwoven fabric corresponding to the soft layer is often softer than the nonwoven fabric corresponding to the hard layer, and is more easily compressed during pressing. Since the layer to be a soft layer is molded in a compressed state, the densities of both layers approach, and a buffer layer having a different density layer cannot be obtained.

However, according to the present invention, a buffer layer having layers having different effective density ratios can be obtained by using the method (b) which is advantageous in terms of manufacturing cost. In the present invention, the formability of the cushioning material layer is ensured by the hard layer, and the formability of the soft layer is set low by suppressing the amount of the heat-adhesive fibers or adhesive mixed therein. For this reason, the soft layer compressed at the time of pressing returns to the original shape by springback after molding, and maintains a desired hardness. Simultaneous integrated pressure molding in the present invention refers to the method (b), that is, a method in which a cushioning material layer having different density layers can be obtained without separately forming a soft layer and a hard layer.

The type of fiber constituting the cushioning material layer is a fiber aggregate mainly composed of synthetic fibers having an average fiber diameter of 2 to 20 denier and an average fiber length of 20 to 100 mm. It is necessary that the areal density is in the range of 400 to 2000 g / m ² .

The sound absorbing performance and the spring constant greatly depend on the fiber diameter, and the performance changes. In most cases, the finer the fineness, the better the sound absorbing performance and the like. However, fine fibers are expensive, the production efficiency for converting the fibers into a nonwoven fabric is reduced, and a reaction force when a desired load is applied to the carpet cannot be obtained. Therefore, it is not desirable to use a fine fiber of 2 denier or less, since the economic merit is reduced, the processability to a nonwoven fabric is reduced, and the desired performance cannot be obtained. Conversely, if it exceeds 20 denier, the sound absorbing performance is greatly reduced, and the purpose of improving the sound insulating performance cannot be achieved.

The synthetic fiber used in the present invention is not particularly limited as long as substantially the same sound insulation performance can be obtained by producing fibers having the same fiber diameter and forming a non-woven fabric. Can be selected and used.
Specific examples thereof include at least one selected from the group consisting of polyester, nylon, polyacrylonitrile, polyacetate, polyethylene, polypropylene, linear polyester and polyamide, and are particularly suitable for distribution and mechanical strength. It is preferable to use polyester which has high cost performance.

The fibers constituting the fiber assembly must be in the range of an average fiber length of 20 to 100 mm. Although the sound absorption performance and the like are not greatly dependent on the fiber length, the fiber length must be within the above range in order to facilitate the production of the fiber aggregate and to improve the mechanical strength of the fiber aggregate.
In particular, in order to improve the performance, an average fiber length of 40 to
It is good to set it in the range of 80 mm, but there is no particular limitation.
If the average fiber length is less than 20 mm, it is too short to produce a nonwoven fabric, and it becomes difficult to entangle the fibers to produce a nonwoven fabric. Conversely, when the average fiber length exceeds 100 mm, it is difficult to uniformly disperse the fibers in the fiber aggregate, and there is a high possibility that only certain types of fibers are biased in the fiber aggregate. It is not suitable for materials that require constant performance in quality.

The surface density of the entire cushioning material layer is 400 to 200.
It must be in the range of 0 g / m ² . This is a surface density range of the fiber assembly layer necessary for securing the sound insulation performance. If the surface density is less than 400 g / m ² , the goal of improving the sound insulation performance cannot be achieved. On the other hand, it is necessary to be 2000 g / m ² or less in view of the necessity of material cost, component weight and spring constant. A fiber aggregate layer exceeding 2000 g / m ² is not preferable because the weight of parts increases. The spring constant is
Increasing the surface density of the fiber assembly layer increases the vibration transmissibility, and therefore, it is not appropriate to increase the fiber aggregate layer so that it exceeds 2000 g / m ² .

In the cushioning material layer having at least two different-density layers constituting the automobile floor insulator carpet of the present invention, the hard layer contains a high-melting polyester fiber A and a low-melting polyester fiber B; When heated below the melting point of the polyester fiber and below the melting point of the high-melting polyester fiber, the non-woven fabric can be shaped into a floor panel by bonding the low-melting polyester fiber and bonding between the fibers. Is preferred. Needle punching may be performed to improve the integrity of the nonwoven fabric.

The polyester fiber A is preferably a polyethylene terephthalate, and the polyester fiber B is a polyester having a core (sheath) having a melting point of 110 to 200 ° C. with respect to the center (core) polyethylene terephthalate. It is preferable that the fibers are bonded to each other when heated at a temperature higher than the melting point of the polyester in the sheath portion and lower than the melting point of polyethylene terephthalate. If the melting point of the polyester in the sheath portion of the polyester fiber B is lower than 110 ° C., the polyester is melted by heat from a floor panel or the like, and the bonding between the fibers is impaired. Conversely, 200
When the temperature exceeds ℃, it is too close to the melting point of polyethylene terephthalate, and the heating conditions during molding become severe.

In the present invention, the soft layer is preferably a nonwoven fabric containing 80 to 95% by weight of the polyester fiber A having a melting point higher by at least 20 ° C. than the polyester fiber B. In addition, the nonwoven fabric may be subjected to a needle punching treatment to improve cohesion. The reason why the melting point is set to be at least 20 ° C. higher than that of the polyester fiber B is that if the melting point is lower than 20 ° C., the heating conditions during molding are severe, the polyester fiber may be melted, and the moldability of the soft layer is increased. It is difficult to obtain the desired performance of the invention. The reason why the nonwoven fabric contains 80 to 95% by weight of the polyester fiber A is that if a component having a low melting point other than the polyester fiber A exceeds 20% by weight, the moldability of the soft layer becomes high, If the amount is less than 5% by weight, the desired cohesiveness cannot be obtained, and it is difficult to obtain the desired performance of the present invention.

The polyester fiber A is preferably a crimped fiber. The crimped fiber has a larger springback after molding, and is better cohesive as a nonwoven fabric. The polyester fiber A is preferably polyethylene terephthalate. This is because the use of a polyester having a low melting point obtained by polymerizing isophthalic acid or the like results in an increase in cost, and the necessity of using a polyester having a low melting point is low in order to obtain the intended performance of the present invention.

Next, the spring constant will be described. In the present invention, the fiber aggregate constituting the cushioning material layer is configured such that the spring constant of at least one of the constituting fiber layers is set to be lower than the spring constant of the other fiber layers, whereby the spring of the entire cushioning material layer is formed. The feature is that the constant is reduced. The sound insulation performance is affected by the spring constant of the fiber assembly, and the smaller the spring constant, the higher the sound insulation performance. The present invention
By making the spring constant of at least one layer of the laminated fiber assembly lower than that of the other fiber layers, a reduction in the spring constant of the entire fiber assembly is achieved.

As a concrete means for lowering the spring constant, means for lowering the density (g / m ³ ) of the layer whose spring is to be reduced is more effective than the other layers. It is also effective to reduce the average diameter of the fibers blended in the layer whose spring is to be reduced to be smaller than that of the other layers. It is most effective to perform the above two at the same time, but there is no particular limitation.

Further, the fiber composition of each layer constituting the fiber assembly will be described. In the present invention, among the fiber aggregate layers constituting the cushioning material layer, the thickest fiber layer is such that the fiber (fiber A) having an average fiber diameter of 2 to 20 denier (Fiber A) is at least 60 to 95% by weight, and at least 20 ° C. is a fiber having a low softening point, the fiber having an average fiber diameter of 1.5 to 10 denier (fiber B) is composed of 5 to 40% by weight, and at least one of the other fiber layers is 2 to 40% by weight. 13 denier fiber (fiber A) is 80 to 95% by weight, and at least 20 ° C. is a fiber having a lower softening point at least 20 ° C., and 1.5 to 10 denier fiber (fiber B) is 5 to 20% by weight. The feature is that it is composed of

The thickest layer has an average fiber diameter of the fiber A of 2 to 2
Consisting of 0 denier fiber, 60-
It is blended at a rate of 95% by weight. This is to improve the sound absorbing performance and obtain a reaction force as a fiber assembly. If the average fiber diameter is less than 2 denier, the fiber diameter is small and the rigidity of the fiber itself is low, so that the fibrous body becomes slack, making it difficult to obtain a desired reaction force. Conversely, if it exceeds 20 denier, it will be difficult to obtain good sound absorbing and insulating properties. On the other hand, if the content of the fiber A is less than 60% by weight, the amount of the fused fiber increases, and it becomes difficult to obtain a spring constant suitable for the sound insulating material. On the other hand, if it exceeds 95% by weight, it is no longer possible to obtain shape retention during molding due to the fused fibers.

Further, the fiber A is desirably a hollow fiber having an opening at the center of a cross section perpendicular to the length direction. Since the rigidity of the fiber can be effectively increased by making it hollow, the shape retention can be improved with a small amount of blending. In addition, since the surface area is increased by the hollow, the sound absorbing performance is also improved. Therefore, it is particularly effective to mix the fiber A hollow fiber, but there is no limitation.

Fiber B is a fiber having a denier of 1.5 to 10 denier and having a softening point lower than that of fiber A by at least 20 ° C.
Binder fiber) and 5 to 4 in the fiber assembly.
It is blended at a ratio of 0% by weight. This means that a certain amount of fibers capable of imparting moldability is required in the fiber aggregate. The sound-insulating material is a major factor for improving the performance of the sound-insulating material to a portion where sound insulation is required, and it is necessary that the fiber aggregate can be formed into a shape that follows a complicated surface shape. The use of the above-mentioned short fibers improves the followability, but it is necessary to add a binder fiber in order to maintain the shape. At the time of heat molding, the binder fiber softens and adheres in a state where the fiber A is constrained in the shape of the mold,
A fine surface shape can be maintained.

At this time, the binder fiber needs to have a denier of 1.5 or more. Binder fibers with a fineness of less than this are not common and increase costs,
In addition to sagging of the binder fiber itself during heat molding, the fiber is completely softened and can be shaped, so the fiber assembly hardens, the spring constant increases significantly, and the sound insulation performance decreases. I do.

The binder fiber must have a denier of 10 denier or less. This is because the use of thick fibers relatively reduces the number of fibers, so that the number of bonding points with other fibers decreases and the shape cannot be maintained.

The reason why the softening point differs by at least 20 ° C. is the difference in the softening point of the fiber itself, which is the minimum necessary for producing a product by heating and press forming while maintaining the shape as a fiber aggregate. . If the difference between the softening points is smaller than this, the entire fibrous body is softened and completely melted into a plate shape.

At least one of the layers other than the above-mentioned thickest layer constituting the fiber aggregate has 80 to 95% by weight of 2 to 13 denier fiber (fiber A), and is at least 20 ° C. 1.5 to 1 fibers having a low softening point
It is characterized in that 0 denier fiber (fiber B) is composed of 5 to 20% by weight.

This layer is laminated for the purpose of reducing the spring constant. This layer is characterized in that the average fiber diameter of the fibers formed is smaller than that of the layer for providing the main sound absorbing performance. Therefore, the spring constant of this layer is reduced.

For the purpose of reducing the spring constant, it is preferable that the content of the fiber B as the binder fiber is as small as possible. When the content of the fiber C exceeds 20% by weight, the bonding between the fibers becomes strong, and the spring constant increases, which is not preferable. However, when the content is less than 5% by weight, the fibers cannot be bonded to each other, so that it is difficult to form a layer, and at the time of forming the fiber aggregate, only the layer is separated from the base layer, and the moldability is reduced. Decrease.

According to the requirement of the fiber B, the mixing of the fiber A is 80
~ 95% by weight. Basically, the smaller the average diameter of the constituent fibers is, the lower the spring constant is. Therefore, it is effective to reduce the spring constant by using the fiber A having a small diameter for the fibers other than the fiber B.

Next, the thickness ratio and the areal density ratio of each layer will be described. Among the fiber layers constituting the cushioning material layer, the thickest fiber layer is characterized by having a thickness ratio of 80 to 97% and an areal density ratio of 80 to 97% with respect to the whole. It is advantageous in terms of moldability that the fiber layer for reducing the spring constant is as thin as possible. This is because cutting and punching of the fiber aggregate becomes difficult when the fine fiber content is large. Therefore, the thickness of the fibrous layer for providing the thickest sound absorbing performance is preferably 80 to 97% in terms of the thickness ratio to the whole. When the thickness ratio is less than 80%, the moldability of the fiber aggregate is extremely reduced. On the other hand, if it exceeds 97%, the effect of reducing the spring constant becomes small, which is not suitable.

The area density ratio is preferably in the range of 80 to 97%. When the areal density ratio is less than 80%, the areal density of the low spring layer increases, and it becomes difficult to reduce the spring constant as compared with the sound absorbing layer. On the other hand, if it exceeds 97%, the rigidity of the low spring layer is extremely reduced, and the layer itself is crushed and formed into a plate shape, which makes it difficult to reduce the spring constant.

In the cushioning material layer having at least two density layers constituting the car floor insulator carpet of the present invention, the thickness of the cushioning material layer (soft layer) disposed on the floor panel side is 0.5 to 10 mm. It is preferably within the range. When the thickness of the cushioning material layer (soft layer) is less than 0.5 mm, the function of the soft layer may be lost due to compression due to the weight of the carpet skin or the hard layer. Meanwhile, 1
If the thickness exceeds 0 mm, the resilience decreases, the sinking under the feet increases, and it becomes difficult to satisfy the function as a carpet. In addition, the ability to follow the hard layer deteriorates, and the fitting of the cushioning material layer to the floor panel becomes difficult. The sex worsens.

The cushioning material layer having at least two density layers constituting the car floor insulator carpet of the present invention can be obtained by simultaneous integral pressure molding. More specifically, a nonwoven fabric corresponding to a hardened layer and a nonwoven fabric corresponding to a soft layer are laminated, and the obtained laminate is made of polyester fiber B.
After heating at a temperature not lower than the melting point of the polyester fiber A and not higher than the melting point of the polyester fiber A, the laminated body is put into a mold, press-formed and simultaneously pressed integrally, and then cooled to the melting point of the polyester fiber B or lower. A buffer layer having at least two density layers is obtained. At this time, it goes without saying that the carpet skin layer 1 and the backing layer 2 can also be laminated on the cushioning material layer and molded at the same time.

[0048]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Embodiment 1 FIG. 3 is a sectional view showing a floor insulator carpet of the present invention. First, the structure will be described. A carpet skin layer 1, a backing layer 2 mainly composed of a thermoplastic resin disposed on the back surface of the carpet skin layer, and a hard layer 3-a and a soft layer 3-b of a cushioning material layer Are sequentially arranged, and the soft layer 3-b of the cushioning material layer is arranged on the floor panel side where vibration and noise enter.

As the carpet skin layer 1, a polyethylene sheet having an areal density of 600 g / m ^{2 and} a backing material 2 having a pile area density of 400 g / m ² are used for a carpet having a pile areal density of 400 g / m ² which are usually used for automobiles such as needle punch carpets and tuft carpets. Was obtained in advance and used.

The hard layer 3-a of the cushioning material layer has an area density of 80
0 g / m ² (15 mm thick) polyester nonwoven fabric,
The soft layer 3-b has a surface density of 200 g / m ² (5 mm thick).
Was prepared. As the fiber composition of the polyester non-woven fabric, the hard layer 3-a is a solid conjugate type of 2 denier × 51 mm: 60 parts, a hollow conjugate type of 6 denier × 51 mm: 20
Part, 2 denier × 51 mm core-sheath type binder fiber (110 ° C. melting type): 20 parts, and the soft layer 3-b is 2 denier × 51 mm solid conjugate type: 6
0 parts, 6 denier × 51 mm hollow conjugate type: 20 parts, 2 denier × 51 mm core-sheath type binder fiber (110 ° C. melting type): 20 parts.

Each of the nonwoven fabrics was laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P.

The melt sheet has a thickness of 2.5 mm (area density of 4.25 mm).
0kg / m ² ), the floor panel is 0.8m thick
m (area density: 6.3 kg / m ² ) were prepared and superimposed in the order shown in FIG. The bonding between the backing material 2 and the cushioning material 3 is performed by melting a polyethylene sheet used for the backing material at 130 ° C. in advance, placing the hard layer side of the cushioning material layer thereon, and then cooling and bonding. did. There is no particular problem even if a spunbond base fabric or a heat-sealed nonwoven fabric is used as the bonding method here.

Generally, floor panels for automobiles have a bead shape for obtaining rigidity or have irregularities for passing a heater duct, a wire harness, and the like. To measure
For convenience, it was left as a flat plate. It goes without saying that the polyester nonwoven fabric used in the present example can be processed along the shape of the floor panel by applying a shape to the mold of the press machine.

The samples obtained by the above-described method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Example 2 The hard layer 3-a of the cushioning material layer had an area density of 970 g / m
² (19.5 mm thick) polyester nonwoven fabric, and a soft layer 3-b were prepared with an areal density of 30 g / m ² (0.5 mm thick) polyester nonwoven fabric. As the fiber composition of the polyester non-woven fabric, a hard layer 3-a, a soft layer 3-b
Both were exactly the same as in Example 1. Molding was performed in exactly the same manner as in Example 1. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were completely the same as in Example 1. Were laminated in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Example 3 The hard layer 3-a of the cushioning material layer had an area density of 370 g / m
² (10 mm thick) polyester nonwoven fabric, soft layer 3
For -b, a polyester nonwoven fabric having an areal density of 30 g / m ² (1 mm thickness) was prepared. As the fiber composition of the polyester nonwoven fabric, the hard layer 3-a and the soft layer 3-b were exactly the same as in Example 1. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were formed in exactly the same manner as in Example 1, and the same method as in Example 1 was used. Were laminated in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Example 4 Example 4 shows a case where the melting point of the binder fiber was changed. The hard layer 3-a of the cushioning material layer has an areal density of 800 g.
/ M ² (15 mm thick) non-woven fabric made of polyester, and a soft layer 3-b, a non-woven fabric made of polyester having an areal density of 100 g / m ² (5 mm thick) was prepared. As the fiber composition of the polyester non-woven fabric, the hard layer 3-a was formed of 2 denier × 5
1 mm solid conjugate type: 60 parts, 6 denier x 51 mm hollow conjugate type: 20 parts, 2 parts
Denier x 51 mm core-sheath type binder fiber (20
(0 ° C. melting type): 20 parts, and the soft layer 3-b is 2 denier × 51 mm solid conjugate type: 60 parts,
6 denier x 51 mm hollow conjugate type: 2
0 parts, 2 denier × 51 mm core-sheath type binder fiber (110 ° C. melting type): 20 parts.

Each of the nonwoven fabrics was laminated, and the laminate was heated in an oven until the temperature reached 215 ° C., and formed so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above-described method were evaluated for sound transmission loss, vibration transmission under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Example 5 The hard layer 3-a of the cushioning material layer had an areal density of 1600 g / m ^2.
(80 mm thick) polyester non-woven fabric, soft layer 3-
For b, a polyester nonwoven fabric having an areal density of 400 g / m ² (10 mm thickness) was prepared. As the fiber composition of the polyester non-woven fabric, the hard layer 3-a was 2 denier × 51 m.
m solid conjugate type: 60 parts, 6 denier ×
51 mm hollow conjugate type: 20 parts, 2 denier × 51 mm core-sheath type binder fiber (110 ° C.
(Melting type): 20 parts, and the soft layer 3-b is 2 denier × 51 mm solid conjugate type: 95 parts, 2 denier × 51 mm core-sheath type binder fiber (11
(0 ° C. melting type): 5 parts.

Each of the nonwoven fabrics was laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the hard layer 3-a became 50 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 16 to 20. Turned out to be obtained. Table 2 shows the results.

Example 6 The hard layer 3-a of the cushioning material layer had an area density of 800 g / m
² (15 mm thick) polyester non-woven fabric, soft layer 3
For -b, a polyester nonwoven fabric having an area density of 200 g / m ² (5 mm thickness) was prepared. As the fiber composition of the polyester non-woven fabric, the hard layer 3-a was 2 denier × 51 m.
m hollow conjugate type: 60 parts, 2 denier ×
51 mm core-sheath type binder fiber (110 ° C. melting type): 40 parts, 13-denier × 5 soft layer 3-b
1 mm hollow conjugate type: 95 parts, 10 denier × 51 mm core-sheath type binder fiber (110
° C melting type): 5 parts.

The molding was performed in exactly the same manner as in Example 5, and a T / P having a thickness of 20 mm for the entire cushioning material layer was obtained. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmission under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Example 7 The hard layer 3-a of the cushioning material layer had an areal density of 800 g / m 2.
² (15 mm thick) polyester non-woven fabric, soft layer 3
For -b, a polyester nonwoven fabric having an area density of 200 g / m ² (5 mm thickness) was prepared. As the fiber composition of the non-woven fabric made of polyester, the hard layer 3-a was made of 20 denier × 51.
mm hollow conjugate type: 95 parts, 1.5 denier × 51 mm core-sheath type binder fiber (110 ° C.
(Melting type): 5 parts, and the soft layer 3-b is 2 denier ×
51mm solid conjugate type: 80 parts, 1.5
Denier x 51 mm core-sheath type binder fiber (1
(10 ° C. melting type): 20 parts.

Each of the nonwoven fabrics was laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. All the performances were equal to or higher than those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Example 8 The hard layer 3-a of the cushioning material layer had an areal density of 800 g / m 2.
² (15 mm thick) polyester non-woven fabric, soft layer 3-
For b, a polyester nonwoven fabric having an area density of 200 g / m ² (5 mm thickness) was prepared. As the fiber composition of the polyester non-woven fabric, the hard layer 3-a was 2 denier × 100 mm.
Solid conjugate type: 20 parts, 6 denier x 5
1 mm hollow conjugate type: 60 parts, 2 denier × 51 mm core-sheath type binder fiber (110 ° C. melting type): 20 parts, and soft layer 3-b is 2 denier ×
51 mm solid conjugate type: 60 parts, 6 denier x 51 mm hollow conjugate type: 20 parts,
2 denier x 51 mm core-sheath type binder fiber (1
(10 ° C. melting type): 20 parts.

Each of the nonwoven fabrics was laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4 having the same thickness. It turned out that the performance of was obtained. Table 2 shows the results.

Example 9 The hard layer 3-a of the cushioning material layer had an areal density of 700 g / m
² (15 mm thick) polyester non-woven fabric, soft layer 3-
For b, a polyester nonwoven fabric having an areal density of 100 g / m ² (5 mm thickness) was prepared. As the fiber composition of the nonwoven fabric made of polyester, the hard layer 3-a was 6 denier × 51 mm.
Hollow conjugate type: 60 parts, 2 denier × 5
1 mm solid conjugate type: 20 parts, 2 denier × 51 mm core-sheath type binder fiber (170 ° C. melting type): 20 parts, and the soft layer 3-b is 2 denier ×
51 mm solid conjugate type: 95 parts, 2 denier × 51 mm core-sheath type binder fiber (170 ° C.
(Melting type): 5 parts.

The respective nonwoven fabrics were laminated, and the laminate was heated in an oven until the temperature reached 195 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P. The carpet skin layer 1, the backing layer 2, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4 having the same thickness. It turned out that the performance of was obtained. Table 2 shows the results. Examples 10 and 11
Shows an embodiment in which three different hardness layers are provided in the cushioning material layer.

Example 10 The hardest layer 3-a of the cushioning material layer had a basis weight of 500 g / m
² (thickness: 7 mm) A nonwoven fabric made of polyester is applied to the softest layer 3-b with a basis weight of 150 g / m ² (thickness: 3 m
m) A nonwoven fabric made of polyester is applied to the buffer material layer 3-c having an intermediate hardness to a basis weight of 700 g / m ² (thickness: 10 m).
m) A polyester nonwoven fabric was prepared. As the fiber composition of the nonwoven fabric made of polyester, the hardest layer 3-a has a hollow conjugate type of 13 denier × 51 mm: 60 parts, a heat-fused fiber of 2 denier × 51 mm core / sheath type (110 ° C. melting type). ): 40 parts. Soft layer 3
-B is 2 denier x 51 mm solid conjugate type: 95 parts, 2 denier x 51 mm core-sheath type heat-fused fiber (110 ° C melting type): 5 parts, 3-c having intermediate hardness Solid conjugate type of 2 denier × 51 mm: 60 parts, hollow conjugate type of 6 denier × 51 mm: 20 parts, heat-fused fiber of 2 denier × 51 mm core / sheath type (110 ° C. melting type): 20 parts did.

Each nonwoven fabric was heated in an oven until the temperature of the nonwoven fabric reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. Carpet skin layer 1, backing layer 2, hard cushioning material layer 3-
a, the cushioning material layer 3-c having an intermediate hardness, the soft cushioning material layer 3-b, the mel sheet layer 4, and the floor panel 5 are the same as those of the first embodiment.
4 were laminated in the order shown in FIG. 4 in the same manner as in Example 1.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Embodiment 11 Embodiment 11 is different from embodiment 10 in that only the order of the buffer layers of 3-a and 3-c is reversed, and 3-c, 3-a, 3-c
An example in the case of overlapping in the order of b is shown. Carpet skin layer 1, backing layer 2, buffer material layer 3 having intermediate hardness
-C, a hard buffer layer 3-a, a soft buffer layer 3-b,
The melt sheet layer 4 and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. All the performances were equal to or higher than those of Comparative Examples 1 to 4. Turned out to be obtained. Table 2 shows the results.

Comparative Example 1 Comparative Example 1 shows the case where urethane foam was used for the cushioning material layer.
You. Urethane foam was prepared by the following method. 20m
m in the injection foaming mold with clearance
Propylene oxide 1,2,6-hexane trio
100 parts, water: 2 parts, surfactant: 1 part, carb
Black: 0.5 parts of solution A and tolylene diisocyanate
Anato: 100 parts, Silicon oil: 0.5 parts or more
Solution B is 1.25 times isocyanate to polyol
The equivalent amount was obtained by injecting a low pressure and foaming. The obtained foamed urethane
The ton sheet has a thickness of 20 mm and an area density of 1200 g /
m ^TwoMet. For bonding between cushioning material layer 3 and backing layer 2
Applied and adhered a spray type adhesive. Carpe
Skin layer 1, backing layer 2, cushioning material layer 3, Merci
Layer 4 and floor panel 5 are exactly the same as in Example 1.
6 and in the order shown in FIG.
Layered.

Comparative Example 2 Comparative Example 2 had exactly the same structure as Comparative Example 1 except that the backing layer used was an ethylene-vinyl acetate copolymer sheet containing calcium carbonate having an areal density of 1500 g / m ² as a filler. And

Comparative Example 3 In Comparative Example 3, the cushioning material layer was made of felt (trade name: Feltop, manufactured by Howa Textile Industry Co., Ltd., thickness: 20 mm, area density: 12).
00g / m ² ). The bonding between the backing material 2 and the cushioning material was performed by previously melting a polyethylene sheet used for the backing material at 130 ° C., placing a cushioning material layer thereon, and then cooling and bonding. The carpet skin layer 1, the backing layer 2, the cushioning material layer 3, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG. .

Comparative Example 4 Comparative Example 4 had exactly the same structure as Comparative Example 3 except that an ethylene-vinyl acetate copolymer sheet containing calcium carbonate having an areal density of 1500 g / m ² as a filler was used for the backing layer. And

Comparative Example 5 As the cushioning material layer 3, a polyester nonwoven fabric having an areal density of 1000 g / m ² was prepared. As for the fiber composition of the polyester non-woven fabric, the hard layer was made of a hollow conjugate type of 6 denier × 51 mm: 50 parts, a heat-fused fiber of a 2 denier × 51 mm core-sheath type (110 ° C. melting type): 50 parts. The nonwoven fabric is heated in an oven until the temperature of the nonwoven fabric reaches 175 ° C., and then the buffer material layer 3 is pressed for 20 m by a press machine.
m.

The carpet skin layer 1, the backing layer 2, the cushioning material layer 3, the mel sheet layer 4, and the floor panel 5 are the same as those of the first embodiment.
6 were laminated in the order shown in FIG. 6 in the same manner as in Example 1. For the sample obtained by the above method, the sound transmission loss, vibration transmission under foot, the results of evaluation of cushioning properties were compared with Comparative Examples 1 to 4,
Since the sample was hard and the resonance frequency was high, it was found that the performance was inferior in sound transmission loss (especially middle frequency of 400 Hz or more).

Comparative Example 6 A nonwoven fabric made of polyester having an areal density of 1000 g / m ² was prepared for the buffer layer 3. The fiber composition of the polyester nonwoven fabric was 2 denier × 51 mm solid conjugate type: 80 parts, 2 denier × 51 mm core-sheath type heat-fused fiber (110 ° C. melting type): 20 parts.
The nonwoven fabric was heated in an oven until the temperature of the nonwoven fabric reached 175 ° C., and then the buffer material layer 3 was formed into a thickness of 20 mm by a press machine.

The carpet skin layer 1, the backing layer 2, the cushioning material layer 3, the mel sheet layer 4, and the floor panel 5 are the same as those of the first embodiment.
6 were laminated in the order shown in FIG. 6 in the same manner as in Example 1. For the sample obtained by the above method, the sound transmission loss, vibration transmission under foot, the results of evaluation of cushioning properties were compared with Comparative Examples 1 to 4,
It was found that the softness of the sample caused the sinking under the foot to be large and sufficient cushioning properties could not be obtained. Comparative Examples 7 and 8 show the case where the buffer layer has two different hardness layers and the hard buffer layer is disposed on the floor panel side.

Comparative Example 7 The soft layer 3-b of the buffer material layer had an area density of 500 g / m
² (15 mm thick) polyester non-woven fabric, hard layer 3
For -a, a polyester nonwoven fabric having an areal density of 500 g / m ² (5 mm thickness) was prepared. As the fiber composition of the non-woven fabric made of polyester, the hard layer 3-a was made of 2 denier × 51.
mm solid conjugate type: 60 parts, 6 denier × 51 mm hollow conjugate type: 20 parts, 2 denier × 51 mm core-sheath type binder binder fiber (11
(0 ° C. melting type): 20 parts, and the soft layer 3-b is 2 denier × 51 mm solid conjugate type: 60 parts,
6 denier x 51 mm hollow conjugate type: 2
0 parts, 2 denier × 51 mm core-sheath type binder fiber (110 ° C. melting type): 20 parts.

The respective nonwoven fabrics were laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P. The carpet skin layer 1, the packing layer 2, the cushioning material layer 3, the mel sheet layer 4, and the floor panel 5 were exactly the same as in Example 1, and were laminated in the same manner as in Example 1 in the order shown in FIG. .

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmissibility under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4, but the first resonance point was higher. It turned out that the performance was inferior in transmission loss (especially middle frequency of 400 Hz or more).

Comparative Example 8 The soft layer 3-b of the buffer material layer had an area density of 500 g / m 2.
² (5mm thick) polyester non-woven fabric, hard layer 3-
For a, a polyester nonwoven fabric having an areal density of 500 g / m ² (15 mm thickness) was prepared. As the fiber composition of the polyester non-woven fabric, the hard layer 3-a was 13 denier × 5.
1 mm hollow conjugate type: 80 parts, 2 denier × 51 mm core-sheath type binder fiber (110 ° C. melting type): 20 parts, and the soft layer 3-b is 2 denier ×
51 mm solid conjugate type: 60 parts, 6 denier x 51 mm hollow conjugate type: 20 parts,
2 denier x 51 mm core-sheath type binder fiber (1
(10 ° C. melting type): 20 parts.

The respective nonwoven fabrics were laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P, and the carpet skin layer 1, the packing layer 2, the cushioning material layer 3, the melsheet layer 4, and the floor panel 5 were exactly the same as in Example 1. And laminated in the order shown in FIG. 8 in exactly the same manner as in Example 1.

The samples obtained by the above method were evaluated for sound transmission loss, transmissibility of vibration under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4, but the first resonance point was higher. It turned out that the performance was inferior in transmission loss (especially middle frequency of 400 Hz or more).

Comparative Example 9 The soft layer 3-b of the buffer material layer had an area density of 150 g / m
² (3mm thick) polyester non-woven fabric, hard layer 3-
The a, a polyester nonwoven fabric areal density 500g / m ² (7mm thick), the buffer material layer 3-c having an intermediate hardness, weight per unit area 700 g / m ² (thickness: 10 mm) made of polyester non-woven fabric Got ready. As the fiber composition of the polyester nonwoven fabric, the hardest layer 3-a has a hollow conjugate type of 13 denier × 51 mm: 60 parts, 2 parts.
Denier × 51mm core-sheath type heat-fused fiber (110 ° C
(Melting type): 40 parts. The soft layer 3-b is a solid conjugate type of 2 denier × 51 mm: 95 parts,
2 denier x 51 mm core-sheath type heat-fused fiber (110
° C melting type): 5 parts, buffer material layer 3 having intermediate hardness
-C: 2 denier x 51 mm solid conjugate type: 60 parts, 6 denier x 51 mm solid conjugate type: 20 parts, 2 denier x 51 mm core-sheath type heat-fused fiber (110 ° C melting type) : 20 parts.

Each of the nonwoven fabrics was laminated, and the laminate was heated in an oven until the temperature reached 175 ° C., and then formed by a press machine so that the thickness of the entire cushioning material layer became 20 mm. One corner of the cushioning material layer thus obtained was cut out to prepare a T / P, and the carpet skin layer 1, backing layer 2, cushioning material layer 3, mel sheet layer 4, and floor panel 5 were exactly the same as in Example 1. And stacked in the order shown in FIG. 9 in exactly the same manner as in Example 1.

The samples obtained by the above method were evaluated for sound transmission loss, vibration transmission factor under foot, and cushioning property. The results were compared with those of Comparative Examples 1 to 4. However, since the sample was soft, the sink under foot was large. It turned out that sufficient cushioning property was not obtained.

Comparative Example 10 In Comparative Example 10, the cushioning material layer was made of felt (trade name: Feltop, manufactured by Howa Textile Industry Co., Ltd., thickness: 10 mm, area density: 6).
00g / m ² ). The bonding between the backing material 2 and the cushioning material was performed by previously melting a polyethylene sheet used for the backing material at 130 ° C., placing a cushioning material layer thereon, and then cooling and bonding.

[0101]

[Table 1]

[0102]

[Table 2]

Test method Sound transmission loss Evaluation was made according to JIS A1416 “Method of measuring sound transmission loss in laboratory”. 2. Underfoot vibration transmissibility A 5kgf φ150 iron disk loader (underfoot load, equivalent to underfoot area) is placed on the sample and forcedly vibrated with a constant vibrating force of 5N, and the vibration transmission gain at 30Hz is measured and compared. did. 3. Cushioning property evaluation Using a hardness tester described in JIS K6382-1978, 5 kg using an iron disk loader of φ150
Measure the sinking amount of the buffer material when a load is applied to f,
The cushioning property was evaluated.

[0104]

【The invention's effect】

1. When the sound transmission loss of the present embodiment and the comparative example are compared with each other with the same thickness, a low frequency of 400 Hz or less,
It excels in performance with an overall value of a medium frequency of 000 Hz and a high frequency of 1000 Hz or more. 2. When the sound transmission loss of this example and the comparative example using the urethane foam were compared with each other for the same thickness, even if the surface density of the backing material was reduced from 1500 g / m ² to 600 g / m ² , the low frequency of 400 Hz or less was obtained. , 400-1000 Hz, medium frequency, high frequency of 1000 Hz or more, and overall value are superior in performance and weight reduction. 3. When the sound transmission loss of this example and the comparative example using felt are compared with each other for the same thickness, the transmission rate and the cushioning property under the foot are superior in performance. 4. A buffer material layer having at least two or more different hardness layers having the above-mentioned effects can provide the same number of steps as a single buffer material layer.

[Brief description of the drawings]

FIG. 1 is a sectional view of a car floor insulator carpet.

FIG. 2 is a sound transmission loss characteristic diagram of a felt specification and a urethane specification.

FIG. 3 is a sectional view of the floor insulator carpet of Examples 1 to 9;

FIG. 4 is a sectional view of a floor insulator carpet according to a tenth embodiment.

FIG. 5 is a sectional view of a floor insulator carpet according to an eleventh embodiment.

FIG. 6 is a sectional view of a floor insulator carpet of Comparative Examples 1 to 6.

FIG. 7 is a cross-sectional view of a floor insulator carpet of Comparative Example 7.

FIG. 8 is a cross-sectional view of a floor insulator carpet of Comparative Example 8.

FIG. 9 is a cross-sectional view of a floor insulator carpet of Comparative Example 9.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carpet skin layer 2 Backing layer 3 Buffer material layer 3-a Hard buffer material layer 3-b Soft buffer material layer 3-c Buffer material layer having intermediate hardness 4 Mel sheet layer 5 Floor panel

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI E04B 1/82 E04B 1/82 H 1/86 1/86 L G10K 11/16 G10K 11/16 D 11/162 A (72) Inventor Ito Nissan Motor Co., Ltd. (72) Yoshikazu Nemoto, Nissan Motor Co., Ltd. (72) Inventor Yoshikazu Nemoto, Nissan Motor Co., Ltd.

Claims (13)

[Claims] 1. A double-walled sound insulation structure, wherein a cushioning material layer constituting the sound insulation structure is composed of at least two different density layers (hard layer-soft layer), and the soft layer is a vehicle body panel. Side, the buffer material layer has an average fiber diameter of 2 to 20 deniers mainly composed of synthetic fibers,
It is a fiber aggregate having an average fiber length in the range of 20 to 100 mm, and the surface density of the entire buffer material layer is 400 to 200.
An automotive floor insulator characterized by being in the range of 0 g / m ² . 2. A synthetic fiber comprising polyester, nylon, polyacrylonitrile, polyacetate, polyethylene,
2. The floor insulator for an automobile according to claim 1, wherein the floor insulator is at least one selected from the group consisting of polypropylene, linear polyester and polyamide. 3. The automotive floor insulator according to claim 1, wherein the synthetic fiber is polyester. 4. The automobile floor insulator according to claim 1, wherein the cushioning material layer is a non-woven fabric made of polyester fibers. 5. A carpet skin layer, a backing layer mainly composed of a thermoplastic resin disposed on the back surface of the carpet skin layer, and a buffer material layer having at least two density layers disposed on the back surface of the backing layer. The floor insulator for a vehicle according to claim 1, wherein are arranged sequentially. 6. The automobile according to claim 1, wherein a soft layer of the cushioning material layer (hard layer-soft layer) having at least two density layers is disposed on the floor panel side. For floor insulator. 7. The spring constant of the entire cushioning material layer is set by setting the spring constant of at least one fiber layer constituting the fiber aggregate constituting the cushioning material layer lower than the spring constant of the other fiber layers. 2. The method according to claim 1, wherein
7. The floor insulator for an automobile according to claim 6. 8. Among the fiber aggregate layers constituting the cushioning material layer, the thickest fiber layer has 60 to 95% by weight of fibers (fiber A) having an average fiber diameter of 2 to 20 denier, which is at least 20% by weight. C is a fiber having a low softening point, a fiber having an average fiber diameter of 1.5 to 10 denier (fiber B) is composed of 5 to 40% by weight, and at least one of the other fiber layers is 2 to 13% by weight. 80 to 95% by weight of denier fiber (fiber A) and 5 to 1.5 denier fiber (fiber B) having a softening point lower than that of said fiber by at least 20 ° C.
The floor insulator for a vehicle according to any one of claims 1 to 7, wherein the weight ratio is set to 20 to 20% by weight. 9. The fiber A is polyethylene terephthalate, and the fiber B is a fiber having a core-sheath structure made of polyester having a melting point of 110 to 200 ° C. in a peripheral portion (sheath portion) of polyethylene terephthalate in a central portion (core portion). 9. The floor insulator for an automobile according to claim 8, wherein: 10. A fiber layer constituting the cushioning material layer, wherein the thickest fiber layer has a thickness ratio of 80 to 97% and an area density ratio of 80 to 97% with respect to the whole. The automobile floor insulator according to claim 1. 11. The automobile floor insulator according to claim 1, wherein the thickness of the cushioning material layer (soft layer) disposed on the floor panel side is in the range of 0.5 to 10 mm. 12. A method for manufacturing a floor insulator for an automobile, wherein a cushioning material layer having at least two density layers is simultaneously obtained by integral press molding. 13. A heating method in which a buffer material layer having at least two density layers is heated at a temperature higher than the melting point of the polyester fiber B and lower than the melting point of the polyester fiber A.
13. The method for manufacturing a floor insulator for an automobile according to claim 12, wherein the method is obtained by simultaneously performing integral pressure molding.