Interior material for vehicle and seat back panel

Abstract

This vehicular interior finishing material has a layered structure including n layers (where n is a natural number equal to or greater than 2), and at least includes a substrate that is a first layer and a skin layer that is an nth layer. The vehicular interior finishing material is configured such that formula (1) is satisfied, where dn (mm) is the thickness of each of the n layers, En (GPa) is the Young's modulus, and ρ (g / cm3) is the density of the entire vehicular interior finishing material. In addition, this seat back panel is formed using the vehicular interior finishing material.

Description

Technical Field

[0001] The present application relates to an interior material for vehicles and a seat back panel using the same.

Background Art

[0002] Conventionally, as a seat back panel of a vehicle, for example, one formed by injection molding of PP (polypropylene) is known. Further, for example, Patent Document 1 describes a press-formed body that can be used as a seat back of a vehicle. The press-formed body of Patent Document 1 is obtained by fixing a skin to a non-woven fabric via an adhesive layer, and Patent Document 1 describes using natural leather, synthetic leather, fabric, or the like as the skin.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to create a high-class cabin space, the interior material for vehicles used as materials such as seat back panels needs to have high rigidity to ensure a visually high-class feeling, and also, even when a tapping sound is generated from the interior material for vehicles, it is desired to generate a tapping sound with a low pitch and good taste. However, generally, when the rigidity of the material is increased, the tapping sound emitted from the material becomes a high-pitched sound lacking in high-class feeling. Therefore, development of an interior material for vehicles that can achieve both high-class feeling in terms of both rigidity and tapping sound is desired. In this regard, the press-formed body described in Patent Document 1 is intended to ensure ease of sewing and strength, and does not consider anything about the tapping sound from the press-formed body.

[0005] This application aims to solve the above problems and provides an interior material for vehicles improved to satisfy the high-class feeling of both appearance and sound, and a seat back panel formed using the same.

Means for Solving the Problems

[0006] To solve the above problems, in one aspect of this application, the interior material for vehicles has a laminated structure of n layers (n is a natural number of 2 or more), and includes at least a base material as the first layer and a skin layer as the nth layer. When the thickness of each of the n layers is dn (mm) and the Young's modulus is En ( M Pa), and the density of the entire interior material for vehicles is ρ (g / cm3), it is configured to satisfy the following formula (1).

[0007]

Number

[0008] Also, the seat back panel of another aspect of this application is formed using any aspect of the interior material for vehicles of this application.

Effects of the Invention

[0009] According to the interior material for vehicles according to this application, while having a high-class appearance by ensuring the necessary rigidity, it can also produce a tasteful sound even when a sound is generated. Further, by using the seat back panel formed using this interior material for vehicles for the seat in the vehicle, the space inside the vehicle can be made to have a high-class feeling.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments of the vehicle interior material according to the present application will be described with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is simplified or omitted.

[0012] Embodiment 1. FIG. 1 is a diagram showing an example of a seat disposed in a vehicle. The vehicle interior material 10 according to the present embodiment is used, for example, as a material for the seat back panel 2 of the vehicle seat 1 as shown in FIG. 1. The seat back panel 2 is particularly in a prominent place in front of a person sitting in the rear seat, occupies a large area in the vehicle interior, and is likely to be hit by a person's hands and feet, and is likely to generate an impact sound. Therefore, by applying the vehicle interior material 10 according to the present embodiment to the seat back panel 2, the appearance of the vehicle interior space can be effectively made to have a high-class feeling, and the generation of an impact sound without elegance can be effectively suppressed.

[0013] However, the vehicle interior material 10 can be suitably used for other parts installed in the vehicle, particularly, parts that a person's hand touches or parts that are easily noticeable to a person's eyes. Specifically, in addition to the seat back panel, the vehicle interior material 10 can be used, for example, as a material that constitutes all or part of a dashboard, an instrument panel, a door trim, a pillar trim, and a rear parcel shelf.

[0014] Figure 2 is a diagram schematically showing a cross-sectional configuration of the vehicle interior material according to the present embodiment. As shown in Figure 2, the vehicle interior material 10 has a laminated structure in which a base material 11 and a skin layer 12 are bonded together.

[0015] As the base material 11, a relatively light material whose composition is adjusted to ensure necessary rigidity is used, and the base material 11 ensures sufficient strength of the vehicle interior parts. Further, the base material 11 is formed using a material that is lighter (has a lower density) than at least the skin layer 12. Specifically, as the material of the base material 11, for example, felt such as fiber, compressed felt or knitted felt, or foamed resin such as urethane foam and a hollow structure of resin (for example, honeycomb structure) are used. Further, the base material 11 may have a structure in which these felts and resins are laminated.

[0016] The skin layer 12 is made of, for example, synthetic leather containing PVC (polyvinyl chloride). Here, the synthetic leather containing PVC includes synthetic leather made only of PVC and synthetic leather having PVC as a main component. Examples of the synthetic leather having PVC as a main component include those in which a resin such as nylon or polyurethane is applied to the surface of PVC. Further, the skin layer 12 may be made of, for example, synthetic leather containing other materials such as PP (polypropylene), fibers such as non-woven fabric and woven fabric, and natural leather. By using these materials, the appearance of the vehicle interior material 10 can be given a high-class feeling.

[0017] Figure 3 is a diagram for explaining an outline of the relationship satisfied by the base material 11 and the skin layer 12 of the vehicle interior material 10 according to Embodiment 1. In Figure 3, the horizontal axis represents the value of α shown in Equation (2). In Equation (2), d1 (mm) is the thickness of the base material 11, d2 (mm) is the thickness of the skin layer 12, E1 ( M Pa) is the Young's modulus of the base material 11 at room temperature (5°C to 35°C), and E2 ( M Pa) is the Young's modulus of the skin layer 12 at room temperature (5°C to 35°C), respectively.

[0018]

Equation

[0019] On the one hand, the vertical axis represents the value of β shown in the following formula (3). In formula (3), ρ (g / cm 3 ) represents the average density of the entire vehicle interior material 10.

[0020]

Number

[0021] The vehicle interior material of the present embodiment is configured to belong to the region C sandwiched between the solid line A and the solid line B. Specifically, α in the above formula (2) is a value correlated with the rigidity of the material. That is, the smaller the value of α, the lower the rigidity. If the value of α becomes excessively small, it becomes difficult to maintain the shape, and the interior material lacks a high-class feeling. In the present embodiment, from the viewpoint of ensuring the rigidity necessary for producing a high-class appearance, as will be described later, the minimum value of α, that is, the range of the solid line B in FIG. 3 is specified, and α of the vehicle interior material 10 is made to be in a range larger than the solid line B.

[0022] Also, generally, as the rigidity increases, the hitting sound from the material becomes a high pitch, and as the mass increases, the hitting sound becomes a low pitch. From this perspective, the inventor of the present application believes that the ratio of mass to rigidity has a certain correlation with the height of the hitting sound from the material, that is, the frequency. As a result of research, it has been found that the ratio β / α can be a parameter indicating the height of the hitting sound.

[0023] Specifically, when the value of the ratio β / α is small, the hitting sound emitted from the material is a sound lacking in high-class frequency. Therefore, in the present embodiment, the value of the ratio β / α within the allowable range as the hitting sound, that is, the slope of the solid line A in FIG. 3 is specified, and the value of the ratio β / α of the vehicle interior material 10 is made to be larger than the slope of the solid line A.

[0024] Figure 4 shows the results of experimentally verifying the α and β values, shape retention force, and sound volume of multiple specific samples of vehicle interior materials. In Figure 4, in the "Sound" column in the rightmost row, the sound pressure level 1 m directly above is shown when the material is vibrated with 10 (N).

[0025] Sample A in Figure 4 is a conventional interior material injection-molded from PP. As shown in Figure 4, the α value of the conventional vehicle interior material is 3104. In the case of Sample A made of PP, the α value was also sufficiently large, and the shape retention force was sufficient. However, β is 2700, and the ratio β / α is relatively small at about 0.87, and it was confirmed that a high-pitched knocking sound occurs.

[0026] For Sample B, α is 94.7 and β is 1522. Sample B has a smaller α value compared to Sample A made of PP, but it was determined to be within an acceptable range from the perspective of shape retention force. On the other hand, the ratio β / α is about 16.07, and the knocking sound was determined to be a low-pitched and high-quality sound.

[0027] Figure 5 shows the sound pressure level for each frequency component of the knocking sound generated when the above Sample A and Sample B are vibrated with a certain intensity. From Figure 5, it can be seen that for Sample A made of conventional PP, Sample B has a sufficiently low sound pressure level on the high-frequency side. From this, it was also confirmed that Sample B is a good vehicle interior material that emits a low-pitched knocking sound.

[0028] For Sample C, α is 2990 and β is 3133. The α value is as large as being close to that of Sample A made of PP, and it is sufficient as a shape retention force. On the other hand, the ratio β / α is about 1.05, and the knocking sound was determined to be within an acceptable range of lower pitch than that of PP.

[0029] Both Sample D and Sample E are examples of upholstered seat back panels. The ratios β / α of Sample D and Sample E are sufficiently small at about 33.61 and about 2.40, and the actual knocking sound is also low-pitched. However, α is small at 9.7 and 87 respectively, and it was determined that the shape retention force is below the acceptable range.

[0030] The experiment using the samples as described above was repeated, and from the viewpoint of rigidity, the range of α of the vehicle interior material 10 of the present embodiment was specified to be greater than 94. Further, from the viewpoint of the knocking sound, the range of the ratio β / α of the vehicle interior material 10 of the present embodiment was specified to be greater than 1, that is, α was specified to be smaller than β. That is, the vehicle interior material 10 of the present embodiment is configured to satisfy the relationship of the following ( 4 ) formula.

[0031] [Number]

[0032] Note that in the above formulas (2) and (4), the Young's modulus at room temperature of 5°C to 35°C is used for the definition. This means that within the range of room temperature of 5°C to 35°C, no matter which temperature's Young's modulus is used for calculation, the relationship of the above formula (4) is satisfied. However, within the range of room temperature, as long as the vehicle interior material 10 satisfies the relationship of formula (4), even in an environment outside the room temperature range, for example, in a high-temperature environment such as the maximum temperature of 80°C in the thermal cycle test, a certain degree of high-class feeling of both rigidity and knocking sound can be satisfied. Further, when the base material 11 or the skin layer 12 is a hollow structure or the like, the Young's modulus may be anisotropic. In that case, the Young's modulus in any of the different directions is used.

[0033] As described above, the vehicle interior material 10 of the present embodiment has a good appearance and emits a knocking sound that does not impair the high-class feeling by satisfying the relationship specified by the above thicknesses d1, d2, Young's moduli E1, E2, and density ρ of the base material 11 and the skin layer 12. Therefore, by using the vehicle interior material 10 for the interior parts of the vehicle, the interior of the vehicle can be given a high-class feeling in appearance, and even when a knocking sound is generated, it can be made into a low-pitched and tasteful sound, and a high-class vehicle interior can be produced as a whole.

[0034] Embodiment 2. FIG. 6 is a diagram schematically showing a cross-sectional configuration of the vehicle interior material according to Embodiment 2. In Embodiment 1, the case where the vehicle interior material 10 is composed of two layers, i.e., a base material 11 and a skin layer 12, has been described. On the other hand, as shown in FIG. 6, the vehicle interior material 20 according to Embodiment 2 has n - 2 intermediate layers between the base material 11 and the skin layer 12. That is, the vehicle interior material 20 is an overall laminated structure of n layers. Here, n is a natural number of 3 or more. For the sake of convenience, the base material 11 is taken as the first layer, and the intermediate layers are sequentially designated as the second layer, the third layer,... the (n - 1)th layer from the side of the base material 11, and the skin layer 12 is described as the nth layer.

[0035] The intermediate layer 13 is disposed for the purpose of adhering the base material 11 and the skin layer 12 and reinforcing the vehicle interior material 10. As the intermediate layer 13, for example, a resin sheet, a non-woven fabric, a fiber, PP, etc. are used. There is no limitation on the number of laminated intermediate layers 13.

[0036] The vehicle interior material 20 is configured to satisfy the following formula (5) in the same manner as the above formula (4). However, in formula (5), the thickness of each layer from the base material 11 as the first layer to the skin layer 12 as the nth layer is represented by dn (mm), the Young's modulus at normal temperature (5 to 35 ° C) is represented by En ( M pa), and the average of the overall density is represented by ρ (g / cm3).

[0037]

Equation

[0038] Even when the vehicle interior material 20 has a laminated structure of three or more layers, by configuring it to satisfy the relationship of the above formula (5), it is possible to achieve both a high-class appearance and a tasteful impact sound of the vehicle interior material 20. Therefore, by using the vehicle interior material 20 for the interior parts of the vehicle, the interior of the vehicle can be given a high-class appearance, and even when an impact sound occurs, it can be made into a low-pitched and tasteful sound, thereby producing a high-class vehicle interior as a whole.

[0039] In the above formula (5), the Young's modulus at room temperature of 5°C to 35°C is also used. As long as it is within the range of room temperature of 5°C to 35°C, the relationship of the above formula (4) is satisfied regardless of the temperature at which the Young's modulus is used for calculation. Further, if a hollow structure or the like is used in any layer and the Young's modulus has anisotropy, the Young's modulus in any of the different directions is used.

[0040] In addition, when referring to the number of each element, quantity, amount, range, etc. in the above embodiments, unless otherwise specified or clearly specified by the principle, the present invention is not limited to the mentioned number. Further, the structure and the like described in this embodiment are not necessarily essential to the present invention, unless otherwise specified or clearly specified by the principle.

Explanation of Reference Numerals

[0041] 1 Sheet 2 Sheet Back Panel 10, 20 Interior Trim Material for Vehicle 11 Base Material 12 Skin Layer 13 Intermediate Layer

Claims

1. An interior trim material for a vehicle having an n-layer (n is a natural number of 2 or more) laminated structure, comprising at least a base material as the first layer and a skin layer as the nth layer, When the thickness of each of the n layers is dn (mm) and the Young's modulus is En (MPa), and the density of the entire vehicle interior material is ρ (g / cm ３ ), and configured to satisfy the following formula (1): 【Number 1】 The interior trim material for a vehicle is characterized by this.

2. The interior trim material for a vehicle according to claim 1, wherein the base material is made of fiber, felt, foamed resin, or a hollow structure of resin.

3. The interior trim material for a vehicle according to claim 1 or 2, wherein the skin layer is made of synthetic leather, non-woven fabric, woven fabric, or natural leather.

4. When n is a natural number of 3 or more and the interior trim material for a vehicle includes an intermediate layer of n - 2 layers disposed between the skin layer and the base material, the interior trim material for a vehicle according to any one of claims 1 to 3, wherein the intermediate layer includes a layer made of any one of a resin sheet, fiber, non-woven fabric, and polypropylene.

5. A seat back panel formed using the interior trim material for a vehicle according to any one of claims 1 to 4.

Images