JPH11206546A - Carpet basic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carpet basic material having high rigidity and to reduce a floor stepping amount die to a load of an occupant in getting on a car by forming a fiber collection body made of polyester fibers into a accumulated layer structure composed of a low density layer and a high density layer which contain specific fibers at predetermined ratios, respectively. SOLUTION: A carpet basic material 2 of a lower carpet 5 is formed by placing a low density layer 3 and a high density layer 4. Here, the high density layer 4 is a fiber collection body which is composed of short fibers made of polyester mainly and has a facial density of 0.1 to 1.0 kg/m<2> and is composed of 0 to 80 wt.% of fiber A having a diameter of 10 to 25 μm and a length of 30 to 100 mm and 20 to 100 wt.% of fiber B having a softening point lower than that of fiber A by at least 20 deg.C. The low density layer 3 is composed of short fibers made of polyester mainly and is composed of 70 to 90 wt.% of fiber C having a diameter of 10 to 40 μm and a length of 30 to 100 mm and 10 to 30 wt.% of fiber D having a softening point lower than that of fiber C by at least 20 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carpet base material that can be used for floor insulators for automobiles and the like.

[0002]

2. Description of the Related Art As shown in FIG. 1, a carpet base material 2 in an automobile floor insulator is located on the vehicle interior side of a floor panel 1 that partitions a vehicle interior from the outside, and supports a passenger's feet when riding. In addition, it has a function to prevent transmission of noise and vibration from outside the vehicle to the occupants. The carpet substrate 2 is composed of a single layer of a porous substrate such as a felt, a polyurethane foam, and a nonwoven fabric. The single-layer base material is provided with a sound absorbing performance to improve the quietness of the passenger compartment, and the mechanical strength is further reduced to reduce the sinking of the floor due to the load of the occupant during the ride (improve the repulsion force). It is configured as follows.

[0003]

In a conventional carpet base material, a floor insulator is constituted by providing a single-layer base material with a function of reducing vibration and noise and reducing sinking for supporting an occupant. However, in order to produce a fiber aggregate base material having these two functions, the ranges of the fiber diameter, the fiber length, and the fiber cross-sectional shape used are contradictory. For example, thin fibers are effective for improving sound vibration performance, but at this time, the sinking amount increases (repulsion force decreases).

The present invention has been made in view of such circumstances, and provides a carpet base material capable of manufacturing a rigid automobile floor insulator in a fiber assembly using polyester fibers. The purpose of the present invention is to reduce the amount of stepping on the floor due to the load of the occupant (improve the resilience).

[0005]

An object of the present invention is to provide a laminated body composed of at least two layers, of which one high-density layer is laminated on one surface of the entire laminated body, The density ratio is 1.5 to 20, the entire laminate has a surface density of 0.3 to 3.0 kg / m ² , and a fiber aggregate having a thickness of 10 to 60 mm. The high-density layer contains polyester as a main component. Area density of 0.1-1.
0 kg / m ² fiber aggregate, fiber diameter 10-25 μm,
A fiber having a circular cross-section or a modified cross-section fiber (fiber A) having a fiber length of 30 to 100 mm is 0 to 80% by weight, and has a softening point lower than that of the fiber A by at least 20 ° C. and has an affinity with the fiber A; Fiber diameter 10-20 μm, fiber length 30-1
The low-density layer has a surface density of 0.2 to 2.0 kg / m ^2.
A fiber aggregate composed of short fibers mainly composed of polyester, having a fiber diameter of 10 to 40 μm and a fiber length of 30 to 10
70 mm to 90% by weight of 0 mm fiber (fiber C)
Having a softening point lower than that of the fiber C by at least 20 ° C. and having a fiber diameter of 10 to 20 μm and a fiber length of 3
This is achieved by a carpet substrate characterized in that 0 to 100 mm of fiber (fiber D) is constituted by 10 to 30% by weight.

First, in order to reduce the amount of sinking, it is necessary to laminate at least two layers of the substrate of the present invention. By laminating at least two layers, a layer having a sound absorbing property for improving the quietness in the vehicle cabin and a layer having a high rigidity for reducing the sinking amount are added to the configuration.
Further, the multilayer structure further improves the sound absorbing performance or the rigidity of the laminate.

One high-density layer constituting the laminate of the carpet substrate of the present invention is laminated on one surface of the entire laminate. In order to reduce the amount of sinking in the floor, if a high-density layer is used as the intermediate layer of the laminate, the fiber assembly layer whose main role is sound absorption performance will support the occupant's feet, The problem cannot be solved. Therefore, it is necessary that the highest-density layer be laminated on one surface of the entire laminate, particularly on the outer surface side in the vehicle interior.

[0008] A preferred density ratio between the high density layer and the low density layer is
1.5 to 20. In order to support the occupant's feet as a carpet base material, the high-density layer in the upper layer of the laminate has the required density,
The rigidity and the like are secured, and the density of the low-density layer is controlled to a density necessary for reduction of the spring constant and sound absorption performance, so that the low-density layer is within the above range. If the density ratio is less than 1.5, it is not substantially different from the single-layer structure, and if the density ratio is more than 20, the weight of the whole laminate becomes excessively large, which is not preferable.

The thickness of the entire laminate is in the range of 10 to 60 mm. When the thickness is less than 10 mm at the density ratio in the above range, sufficient sound vibration performance cannot be obtained. In addition, from the viewpoint of improving the sound absorbing performance, the larger the thickness is, the better.

[0010] The surface density of the entire laminate is 0.3 to 3.0 kg.
/ M ² . When the carpet base material forms a laminate composed of at least two layers of a low-density layer serving as a sound-absorbing layer and a high-density layer providing rigidity, the low-density layer is used in order to satisfy required sound vibration performance. Some weight is required. In addition, the high-density layer that imparts rigidity to the carpet base material in reducing the sinking amount also needs a certain weight in order to ensure its mechanical strength. However, if it exceeds 3.0 kg / m ² , the component weight becomes excessive, which is not preferable. If it is less than 0.3 kg / m ² , the rigidity required by the high-density layer to reduce the sinking amount cannot be secured.

The high-density layer of the laminate layer constituting the carpet substrate of the present invention mainly has an effect of reducing sinking under the foot due to the load of the occupant.

The area density of the high-density layer is 0.1 to 1.0 kg /
The reason for setting the range of m ² is that if it is less than 0.1 kg / m ^2, it is difficult to obtain a satisfactory rigidity, whereas if it exceeds 1.0 kg / m ² , it is not preferable from the viewpoint of an increase in material cost and an increase in parts weight. .

As the fiber material of the high-density layer, polyester is suitable from the viewpoints of flowability and mechanical strength, and is also preferable because of its high cost performance. In addition, fibers such as nylon, polyacrylonitrile, polyacetate, polyethylene, and polypropylene can also be used. By manufacturing fibers having the same diameter and forming a nonwoven fabric, almost the same rigidity can be obtained, and there is no particular limitation.

Particularly, the fiber A is a short fiber mainly composed of polyester, usually polyethylene terephthalate, and is composed of a fiber having a diameter of 10 to 25 μm and a fiber of 30 to 100 mm in circular cross section or irregular cross section. It is blended in a ratio of 0 to 80% by weight.

As the fiber A, a fiber having a fiber diameter of less than 10 μm is not preferable because it is difficult to manufacture the fiber and it is difficult to stably supply the fiber, and the cost is increased. Moreover, it becomes difficult to mix with other fibers B, and it becomes difficult to obtain a uniform fiber aggregate. In addition, a thick fiber having a fiber diameter of more than 25 μm has a significantly reduced number of fiber bonding points, and is not suitable for obtaining sufficient rigidity. By blending the fine denier fiber as much as possible, the number of fibers in the fiber assembly is increased, the number of joining points is increased, a dense layer is formed, and the rigidity is improved.

The fiber A becomes a denser layer by using short fibers, and the rigidity is further improved by using a modified cross section. The preferred fiber length of the fiber A is 30 to
It is in the range of 100 mm. It is desirable to be within the above range from the viewpoint of the effect on the surface area in the fiber assembly and the improvement of the mechanical strength of the fiber assembly. A fiber having a fiber length of less than 30 mm is inferior in workability during the production of a nonwoven fabric, and if it exceeds 100 mm, it is difficult to uniformly disperse it in a fiber aggregate, and it is not a sufficient material for demanding stable high quality.

The preferred amount of the fiber A is from 0 to 80% by weight. If it is more than this, it is difficult to control the thickness of the high-density layer,
There is a possibility that a sufficient density cannot be secured.

The fiber B has a fiber diameter of 10 to 20 μm and a fiber length of 3
0-100 mm, a fiber having an affinity for the fiber A and having a softening point lower than that of the fiber A by at least 20 ° C. (hereinafter, referred to as “binder fiber”);
It is blended at a ratio of 0% by weight. This means that it is necessary to incorporate fibers capable of imparting moldability into the high-density layer. When the carpet substrate of the present invention is used for an automobile interior material, it is preferable that it can be molded so as to follow the surface shape of the body panel. Although the followability is improved by using the short fibers described above, the binder fibers play a role of maintaining and fixing the shape. At the time of heat molding, the binder fiber is softened and adhered in a state where the fiber A is constrained in the shape of the mold, so that a complicated surface shape can be maintained.

If the fiber diameter of the binder fiber is less than 10 μm, it becomes difficult to produce the binder fiber, which is not common and increases the cost. In addition, the binder fibers themselves are sagged at the time of heat molding, and are hardly mixed with the fibers A, so that it is difficult to obtain a uniform fiber aggregate. On the other hand, the binder fiber is 20μ
m or less. When a thicker fiber is used, the number of fibers is relatively reduced, so that the number of bonding points with other fibers is reduced, and it becomes difficult to maintain the shape.

The fiber length of the fiber B is in the range of 30 to 100 mm. It is preferable to be within the above range from the viewpoint of the effect on the surface area of the fiber assembly and the improvement of the mechanical strength of the fiber assembly. Fibers having a fiber length of less than 30 mm are inferior in workability in producing a nonwoven fabric, and fibers having a fiber length of more than 100 mm are difficult to disperse uniformly in a fiber aggregate, and are not a sufficient material for demanding stable high quality.

The fiber B is formed of a fiber material having an affinity for the fiber A. That is, when the fiber A is a polyester, a copolymerized polyester or a modified polyester may be used, but the softening point temperature of the fiber B is lower than that of the fiber A.
At least 20 ° C lower. The reason for this is the difference in the softening point of the fiber itself, which is the minimum necessary to produce 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 risk that the entire fiber assembly is softened increases.

The fiber B is preferably 2
It is preferable to mix at a ratio of 0 to 100% by weight. 2
If it is less than 0% by weight, molding becomes difficult.

Further, the high-density layer is preferably a fiber aggregate layer having a thickness ratio of 4 to 35% of the whole. In order to reduce the amount of sinking, the entire base material may be formed as a thin layer with high density to have high rigidity. However, the vibration transmission rate is high, that is, the spring constant is deteriorated. Therefore, in order to provide high rigidity without deteriorating the spring constant, it is preferable that the high-density layer has a thickness ratio of 4 to 35% in the laminate layer. It is difficult to reduce the thickness to less than 4% from the viewpoint of molding the high-density layer, and the thickness ratio is not preferable because the low-density layer becomes almost a single layer. On the other hand, if it exceeds 35%, the spring constant is undesirably deteriorated.

Further, the low-density layer constituting the laminated structure mainly has the effect of reducing the vibration transmission coefficient and improving the sound absorption coefficient.

The fiber aggregate of the low density layer has an area density of 0.2 to 0.2.
It is preferably in the range of 2.0 kg / m ² . If the areal density is less than 0.2 kg / m ² , satisfactory sound absorbing performance cannot be obtained. On the other hand, if it exceeds 2.0 kg / m ² , the material cost is increased and the weight of parts is increased, which is not preferable.

As a fiber material, polyester is suitable from the viewpoints of flowability and mechanical strength, and has high cost performance. Also, nylon, polyacrylonitrile,
Fibers such as polyacetate, polyethylene, and polypropylene can also be used, and by producing fibers of the same diameter and forming a nonwoven fabric, substantially the same sound absorbing performance and vibration transmissibility can be obtained, and there is no particular limitation.

In particular, the fiber C is a short fiber mainly composed of polyester, usually polyethylene terephthalate, and has a fiber diameter of 10 to 40 μm and a fiber length of 30 to 100 mm. It is blended in a ratio of weight%.

In order to improve the sound absorbing performance and reduce the vibration transmissibility, it is desirable to mix a large number of fine denier fibers. However, as a result, the shape retention of the low-density layer is reduced, and sag occurs, making it impossible to secure the thickness required to satisfy the required performance. Therefore, it is necessary to mix fibers that are equivalent or relatively thick compared to the fibers A to be mixed in the high-density layer. However, if it exceeds 40 μm, it is not suitable for obtaining good sound insulation performance.

As the fiber C, a fiber having a fiber diameter of less than 10 μm is not preferable because it is difficult to produce the fiber and it is difficult to stably supply the fiber and the cost increases. Moreover, it becomes difficult to mix with other fibers D, and it is difficult to obtain a uniform fiber aggregate. In addition, a thick fiber having a fiber diameter exceeding 40 μm has a remarkably reduced number of fiber bonding points, and is not suitable for obtaining appropriate rigidity and moldability.

The preferable fiber length of the fiber C is 30 to 100 m
m. It is desirable to be within the above range from the viewpoint of the influence on the surface area in the fiber aggregate related to the sound absorbing performance and the control of the spring constant. A fiber having a fiber length of less than 30 mm is inferior in workability during the production of a nonwoven fabric, and if it exceeds 100 mm, it is difficult to uniformly disperse it in a fiber aggregate, and it is not a sufficient material for demanding stable high quality.

The preferred amount of the fiber C is from 70 to 70 from the viewpoints of securing sound absorption performance, reducing the spring constant, and securing moldability.
Preferably it is 90% by weight. If it is less than 70% by weight, the proportion of the fiber D relatively increases, which undesirably leads to an increase in the spring constant. On the other hand, if the content exceeds 90% by weight, the proportion of the fiber D is too small, so that the moldability cannot be ensured. If it is larger than this, it is difficult to control the thickness of the high-density layer, and there is a possibility that a sufficient density cannot be secured.

The fiber D has a fiber diameter of 10 to 20 μm and a fiber length of 3
A fiber having an affinity for the fiber C and having a softening point lower than that of the fiber C by at least 20 ° C. (hereinafter referred to as “binder fiber”);
It is blended in a ratio of weight%. This means that it is necessary to incorporate fibers capable of imparting moldability into the low density layer.
When the carpet substrate of the present invention is used for an automobile interior material, it is preferable that it can be molded so as to follow the surface shape of the body panel. The binder fiber plays a role of maintaining and fixing its shape as in the case of the binder fiber (fiber B) described above.

If the fiber diameter of the fiber D is less than 10 μm, it becomes difficult to manufacture the fiber D, which is not common and increases the cost. In addition, the binder fibers themselves are sagged during the heat molding, and are hardly mixed with the fibers C, making it difficult to obtain a uniform fiber aggregate. On the other hand, the binder fiber preferably has a size of 20 μm or less. When a thicker fiber is used, the number of fibers is relatively reduced, so that the number of bonding points with other fibers is reduced, and it becomes difficult to maintain the shape.

The fiber length of the fiber D is in the range of 30 to 100 mm. It is preferable to be within the above range from the viewpoint of the effect on the surface area of the fiber assembly and the improvement of the mechanical strength of the fiber assembly. Fibers having a fiber length of less than 30 mm are inferior in workability in producing a nonwoven fabric, and fibers having a fiber length of more than 100 mm are difficult to disperse uniformly in a fiber aggregate, and are not a sufficient material for demanding stable high quality.

The fiber D is formed of a fiber material having an affinity for the fiber C. That is, when the fiber C is a polyester, a copolymerized polyester or a modified polyester may be used, but the softening point temperature of the fiber D is lower than that of the fiber C.
At least 20 ° C lower. If the difference between the softening points is smaller than this, the risk of the entire low-density layer being softened increases. Fiber D is 10 to 3 from the viewpoint of ensuring moldability and density.
It is preferable to mix at a ratio of 0% by weight. 10% by weight
If it is less than 10, molding becomes difficult.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The application of the carpet base material of the present invention to an automobile floor insulator will be described. It is important in terms of required performance to ensure sound insulation performance in a low frequency range for floor parts for automobiles. It is also important to control the amount of sinking in terms of merchantability, such as stepping comfort when riding. Therefore, in FIG. 1 attached hereto, by applying the carpet substrate 2 of the present invention to a floor insulator for an automobile, the sound insulation performance required for floor components is satisfied, and the sinking amount required for floor components is reduced. It becomes possible.

Therefore, it is possible to install the carpet base material 2 of the present invention on the entire floor of an automobile floor part or at a position where an occupant places his / her feet. By installing the carpet base material of the present invention on the entire floor, sound and vibration performance is improved,
There is no problem in terms of the required performance level, cost, manufacturing process, and the like, and there is no problem with the configuration in which the occupant is installed only at the position where the occupant places his or her feet. In addition, polyester is often used for the carpet skin 5 used for an automobile floor insulator. By combining with the carpet base material of the present invention, the entire floor insulator can be manufactured from polyester, and burrs generated in the process can be obtained. Etc. can be improved.

Next, control of the resonance frequency will be described. By installing the carpet base material of the present invention on an automobile floor panel and a partition wall, a double-walled sound insulation structure is formed by at least one high-density layer 4 and an external partition wall in a fiber assembly constituting the carpet base material. I do.

In order to improve the sound insulation performance, it is preferable to form an external partition and a double-wall sound insulation structure using the carpet substrate of the present invention. However, as a characteristic of the double-walled sound insulation structure, a resonance phenomenon occurs at a certain frequency on the sound insulation performance curve. Therefore, by shifting this resonance point to a lower frequency side, the entire sound insulation performance curve with respect to the frequency can be shifted to the lower frequency side to improve the performance.

The primary resonance frequency of the double-walled sound insulation structure having the porous material 3 inserted therein is generally approximated by the equation (1). f = 1 / 2π · [｛(m ₁ + m ₂ ) / m ₁ · m ₂ ｝ · E / d] ¹ / _2- (1) where m ₁ and m ₂ are external partition walls and high density layers Area density, E
Is the Young's modulus of the internal low density layer, d is the thickness of the low density layer, and Young's modulus is calculated from the elastic modulus and the like.

However, since the double-walled sound insulation structure according to the present invention does not form a complete double wall, the primary resonance frequency cannot be determined only by equation (1). Therefore, as a specific means to set the resonance point arbitrarily, it is effective to set the low frequency by manipulating the fiber composition of the low density layer, increase the thickness, increase the density, and reduce the dynamic spring constant. It is. By performing all of these operations simultaneously, a more precise resonance point setting operation becomes possible.

[0042]

Examples of the present invention will be described below. The following experiment was performed about the carpet base material obtained in the Example and the comparative example. (Hardness test) The rebound force of the samples obtained by the methods of the examples and the comparative examples was measured using the hardness test method of JIS K6401.

(Example 1) The high-density layer had an area density of 200 g /
cm ² , thickness 2mm, fineness 14μm, fiber length about 50m
m polyester fiber A is 50% by weight and fineness 14μ
m, a fiber length of about 50 mm, a polyester fiber B having a softening point of 130 ° C. lower than that of the fiber A, comprising 50% by weight, a low density layer having an area density of 875 g / cm ² , a thickness of 35 mm, and a fineness of 2
5 μm polyester fiber C having a fiber length of about 50 mm is 90
A carpet base material (1) was produced using a fiber assembly composed of 10% by weight and 10% by weight of a polyester fiber D having a fineness of 14 μm, a fiber length of about 50 mm, and a softening point 130 ° C. lower than that of the fiber C.

Example 2 The high-density layer had an area density of 100 g.
A carpet substrate (2) was produced in exactly the same manner as in Example 1 except that the ratio was / cm ² .

Example 3 The area density of the high-density layer was 1000
A carpet substrate (3) was produced in exactly the same manner as in Example 1 except that g / cm ² was used.

(Example 4) Polyester fiber A having a fineness of 10 μm and a fiber length of 50 mm was 50% by weight, and the softening point was 9 μm than that of fiber A with a fineness of 14 μm and a fiber length of about 50 mm.
Carpet base material (4) in exactly the same manner as in Example 1 except that polyester fiber B, which is 0 ° C lower, is composed of 50% by weight.
Was prepared.

(Example 5) Polyester fiber A having a fineness of 25 μm and a fiber length of 50 mm was 50% by weight, and the softening point was 90 μm than that of the fiber A at a fineness of 14 μm and a fiber length of 50 mm.
A carpet substrate (5) was produced in exactly the same manner as in Example 1 except that the polyester fiber B lower by 50 ° C. was constituted by 50% by weight.

Example 6 A polyester fiber A having a fineness of 14 μm and a fiber length of 30 mm was 50% by weight, and a softening point of 90% was higher than that of the fiber A at a fineness of 14 μm and a fiber length of 50 mm.
A carpet substrate (6) was produced in exactly the same manner as in Example 1, except that the polyester fiber B lower by 50 ° C. was constituted by 50% by weight.

(Example 7) The polyester fiber A having a fineness of 14 μm and a fiber length of 100 mm was 50% by weight.
Fineness 14μm, Fiber length 50mm, softening point 9 more than fiber A
Carpet base material (7) in exactly the same manner as in Example 1 except that polyester fiber B, which is 0 ° C lower, is composed of 50% by weight.
Was prepared.

Example 8 Polyester fiber B having a high-density layer having a fineness of 14 μm, a fiber length of 50 mm and a softening point of 175 ° C.
Was made in the same manner as in Example 1 except that the carpet substrate (8) was constituted by 100% by weight.

(Example 9) Polyester fiber A having a fineness of 14 μm and a fiber length of 50 mm was 80% by weight, and a softening point of 90% was higher than that of fiber A when the fineness was 14 μm and the fiber length was 50 mm.
A carpet substrate (9) was produced in exactly the same manner as in Example 1 except that the polyester fiber B lower by 20 ° C. was constituted by 20% by weight.

Example 10 The high-density layer had a fineness of 14 μm.
50% by weight of a polyester fiber A having a fiber length of 50 mm,
Fineness is 10μm, fiber length is 50mm and softening point is 9 more than fiber A
Except that the polyester fiber B lower by 0 ° C. is constituted by 50% by weight, the carpet base material (1
0) was prepared.

Example 11 The high-density layer had a fineness of 14 μm,
50% by weight of a polyester fiber A having a fiber length of 50 mm,
Fineness 20μm, fiber length 50mm, softening point 9 than fiber A
Except that the polyester fiber B lower by 0 ° C. is constituted by 50% by weight, the carpet base material (1
1) was produced.

Example 12 The high-density layer had a fineness of 14 μm.
50% by weight of a polyester fiber A having a fiber length of 50 mm,
Fineness is 20μm, fiber length is 30mm and softening point is 9 more than fiber A
Except that the polyester fiber B lower by 0 ° C. is constituted by 50% by weight, the carpet base material (1
2) was produced.

Example 13 The high-density layer had a fineness of 14 μm,
50% by weight of a polyester fiber A having a fiber length of 50 mm,
Except that the polyester fiber B having a fineness of 14 μm, a fiber length of 100 mm, and a softening point 90 ° C. lower than that of the fiber A is composed of 50% by weight, the carpet base material (1
3) was produced.

Example 14 The low-density layer had an area density of 200.
A sound-insulating structure (14) was produced in exactly the same manner as in Example 1 except that g / cm ² was used.

Example 15 The low-density layer had an area density of 200.
A sound insulation structure (15) was produced in exactly the same manner as in Example 1 except that the amount was set to 0 g / cm ² .

Example 16 The low-density layer had a fineness of 10 μm.
90% by weight of polyester fiber C having a fiber length of 50 mm,
Fineness 14μm, Fiber length 50mm, softening point 9 more than fiber C
Carpet base material (1) was prepared in exactly the same manner as in Example 1 except that polyester fiber D, which was 0 ° C lower, was constituted by 10% by weight.
6) was produced.

Example 17 The low-density layer had a fineness of 40 μm,
90% by weight of polyester fiber C having a fiber length of 50 mm,
Fineness 14μm, Fiber length 50mm, softening point 9 more than fiber C
Carpet base material (1) was prepared in exactly the same manner as in Example 1 except that polyester fiber D, which was 0 ° C lower, was constituted by 10% by weight.
7) was produced.

Example 18 The low-density layer had a fineness of 25 μm,
90% by weight of polyester fiber C having a fiber length of 30 mm,
Fineness 14μm, Fiber length 50mm, softening point 9 more than fiber C
Carpet base material (1) was prepared in exactly the same manner as in Example 1 except that polyester fiber D, which was 0 ° C lower, was constituted by 10% by weight.
8) was produced.

Example 19 The low-density layer had a fineness of 25 μm,
90% by weight of 100 mm polyester fiber C
A carpet substrate (19) was produced in exactly the same manner as in Example 1 except that 10% by weight of a polyester fiber D having a fineness of 14 μm, a fiber length of 50 mm, and a softening point lower than that of the fiber C by 90 ° C. was 10% by weight.

Example 20 The low density layer had a fineness of 25 μm,
70% by weight of polyester fiber C having a fiber length of 50 mm,
Fineness 14μm, Fiber length 50mm, softening point 9 more than fiber C
Carpet base material (2) was prepared in exactly the same manner as in Example 1 except that polyester fiber D, which was 0 ° C lower, was constituted by 30% by weight.
0) was prepared.

Example 21 The low-density layer had a fineness of 25 μm,
90% by weight of polyester fiber C having a fiber length of 50 mm,
Fineness 10μm, fiber length 50mm, softening point 9 than fiber C
Carpet base material (2) was prepared in exactly the same manner as in Example 1 except that polyester fiber D at 0 ° C. was constituted by 10% by weight.
1) was produced.

Example 22 The low-density layer had a fineness of 25 μm,
90% by weight of polyester fiber C having a fiber length of 50 mm,
Fineness 20μm, fiber length 50mm, softening point 9 than fiber C
Carpet base material (2) was prepared in exactly the same manner as in Example 1 except that polyester fiber D at 0 ° C. was constituted by 10% by weight.
2) was produced.

Example 23 The low density layer had a fineness of 25 μm,
90% by weight of polyester fiber C having a fiber length of 50 mm,
Fineness 14 µm, fiber length 30 mm, softening point 9 higher than fiber C
Carpet base material (2) was prepared in exactly the same manner as in Example 1 except that polyester fiber D at 0 ° C. was constituted by 10% by weight.
3) was produced.

(Example 24) The low-density layer had a fineness of 25 µm.
90% by weight of polyester fiber C having a fiber length of 50 mm,
Carpet base material (2) was prepared in exactly the same manner as in Example 1 except that polyester fiber D having a fineness of 14 μm, a fiber length of 100 mm, and a softening point 90 ° C. lower than that of fiber C was constituted by 10% by weight.
4) was produced.

(Example 25) The difference in softening point between polyester fiber A and polyester fiber B forming a high-density layer was 20 ° C.
A carpet substrate (25) was produced in exactly the same manner as in Example 1 except that

(Example 26) The difference in softening point between the polyester fiber C and the polyester fiber D forming the low density layer was 20 ° C.
A carpet substrate (26) was produced in exactly the same manner as in Example 1 except for the following.

(Comparative Example 1) The area density of the high-density layer was 2000
An attempt was made to produce a carpet substrate (27) in exactly the same manner as in Example 1 except that the amount was set to g / cm ² , but the thickness could not be controlled and the production was not possible.

(Comparative Example 2) A carpet substrate (28) was prepared in exactly the same manner as in Example 1 except that the thickness of the high-density layer was reduced to 1 mm or less. And could not be produced.

(Comparative Example 3) A polyester fiber A having a fineness of 5 μm and a fiber length of 50 mm was 50% by weight, and a softening point was 90 ° C. than that of the fiber A with a fineness of 14 μm and a fiber length of 50 mm.
An attempt was made to produce a carpet substrate (30) in exactly the same manner as in Example 1 except that the low polyester fiber B was constituted by 50% by weight, but the fiber A was too thin to form a nonwoven fabric and could not be produced. Was.

(Comparative Example 4) A carpet substrate (31) was prepared in exactly the same manner as in Example 1 except that the high-density layer was composed of only 100% by weight of polyester fiber A having a fineness of 14 µm and a fiber length of 50 mm. However, the thickness could not be made sufficiently thin, and thus it could not be produced.

(Comparative Example 5) A polyester fiber A having a fineness of 14 μm and a fiber length of 50 mm was 50% by weight, and the softening point was 90 ° C. than that of the fiber A when the fineness was 5 μm and the fiber length was 50 mm.
An attempt was made to produce the carpet substrate (32) in exactly the same manner as in Example 1 except that the low polyester fiber B was constituted by 50% by weight, but the fiber B was too thin to form a nonwoven fabric and could not be produced. .

(Comparative Example 6) The low-density layer had an area density of 100 g.
A carpet substrate (33) was produced in exactly the same manner as in Example 1 except that the ratio was / cm ² .

(Comparative Example 7) The low-density layer had a fineness of 5 μm and a fiber length of 50 mm, and 90% by weight of polyester fiber C. The fineness was 14 μm, the fiber length was 50 mm, and the softening point was 90 ° C.
An attempt was made to produce a carpet substrate (34) in exactly the same manner as in Example 1 except that the low polyester fiber D was constituted by 10% by weight, but the fiber C was too thin to be a nonwoven fabric and could not be produced. .

(Comparative Example 8) The polyester fiber C having a fineness of 25 μm and a fiber length of 50 mm was 50% by weight in the low-density layer, and the softening point of the fiber C was 14 μm and the fiber length was 50 mm.
Carpet base material (35) in exactly the same manner as in Example 1 except that polyester fiber D, which is 50 ° C lower, is composed of 50% by weight.
Was prepared.

(Comparative Example 9) A carpet substrate (36) was produced in exactly the same manner as in Example 1 except that the low-density layer was composed of only 100% by weight of polyester fiber C having a fineness of 25 µm and a fiber length of 50 mm. However, it did not show a molded body and could not be produced.

Comparative Example 10 The low-density layer had a fineness of 25 μm.
90% by weight of polyester fiber C having a fiber length of 50 mm,
With a fineness of 5 μm and a fiber length of 50 mm, the softening point is 90
Carpet base material (37) in exactly the same manner as in Example 1 except that polyester fiber D lower by 10 ° C. was constituted by 10% by weight.
However, the fiber D was too thin to form a non-woven fabric, and could not be produced.

(Comparative Example 11) A carpet substrate (38) was produced in exactly the same manner as in Example 1 except that the difference in melting point between the polyester fiber C and the polyester fiber D forming the low density layer was 10 ° C.

Tables 1 and 2 collectively show the results of the above Examples and Comparative Examples and the results of testing the repulsion of the products obtained by the Examples and Comparative Examples.

[0081]

[Table 1]

[0082]

[Table 2]

In the results shown in Tables 1 and 2, 25%
Those having a rebound force of less than 20 kgf at the time of compression were judged to have no effect. From these tables, it was confirmed that each of the carpet base materials manufactured in the examples can obtain a very high repulsive force. In addition, in the case of the comparative example manufactured according to the specification out of the regulation of the present invention, a satisfactory value could not be obtained with respect to the repulsion at the time of 25% compression.

[0084]

As described above, the carpet substrate of the present invention is obtained by laminating high-density layers having high rigidity,
It has an effect that the resilience is significantly improved as compared with a conventional carpet base material formed of a single layer. That is, the sound insulation structure using the carpet base material of the present invention is a laminate of at least two layers, compared with a conventional product of the same shape and the same weight manufactured by a single layer, and the repulsion force at the time of compression is improved, It is suitable as a cushion material.

[Brief description of the drawings]

FIG. 1 is a schematic view of a floor insulator mounted on a vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Floor panel 2 Carpet base material 3 Low density layer 4 High density layer 5 Floor carpet

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Satoshi Nagashima 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Inside Nissan Motor Co., Ltd. (72) Yoshikazu Nemoto 2 Takaracho, Kanagawa-ku, Yokohama City, Kanagawa Nissan Motor Co., Ltd. (72) Inventor Hiroshi Sugawara 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Nissan Motor Co., Ltd.

Claims (7)

[Claims] 1. A laminated body comprising at least two layers, of which one high-density layer is laminated on one surface of the whole laminated body and has a density ratio of 1.5 to 20 with respect to a low-density layer.
And the overall density of the laminate is 0.3 to 3.0 kg / m.
² , a fiber aggregate having a thickness of 10 to 60 mm, wherein the high-density layer is a fiber aggregate composed of short fibers mainly containing polyester having a surface density of 0.1 to 1.0 kg / m ² ,
A fiber having a fiber diameter of 10 to 25 μm and a fiber length of 30 to 100 mm (fiber A) is 0 to 80% by weight, and has a softening point lower than that of the fiber A by at least 20 ° C. and has an affinity with the fiber A; The fiber (fiber B) having a diameter of 10 to 20 μm and a fiber length of 30 to 100 mm is constituted by 20 to 100% by weight, and the low-density layer is mainly composed of a polyester having a surface density of 0.2 to 2.0 kg / m ^2. A fiber assembly composed of short fibers, the fiber having a fiber diameter of 10 to 40 μm and a fiber length of 30 to 100 mm (fiber C) is 70 to 90% by weight, and has a softening point lower than that of the fiber C by at least 20 ° C. Having an affinity for the fiber C, a fiber diameter of 10 to 20 μm, and a fiber length of 30 to 100.
A carpet base material comprising 10 to 30% by weight of fiber (fiber D) having a thickness of 10 mm. 2. The carpet substrate according to claim 1, wherein a thickness ratio of the high-density layer to the whole is 4 to 35%. 3. The carpet substrate according to claim 1, wherein the fibers A are fibers having a circular cross section. 4. The carpet substrate according to claim 1, wherein the fiber A is a fiber having a modified cross section. 5. The method according to claim 1, wherein the laminated body is applied to the entire surface of a floor insulator for a vehicle in a state where a carpet is installed above a high-density layer side of the laminate. ~ 4 any of the carpet substrate. 6. The method according to claim 1, wherein the step is applied only to the position below the occupant's feet of the automobile floor insulator in a state where a carpet is installed on an upper portion of the laminated body, which is located on an interior side of a floor panel of the automobile. ~ 4 any of the carpet substrate. 7. The double-walled sound insulating structure is formed by installing the laminate on a floor panel and a partition of an automobile, and by using at least one high-density layer in the laminate and an external partition. Item 7. The carpet substrate according to item 5 or 6.