Vehicle interior material and seat back panel

Abstract

One example of the interior material for a vehicle in the present application is a layered structure body including at least a base material and a skin layer. When the average of the surface roughness of the base material in the horizontal direction is set as RSm (mm), the Young's modulus of the base material at 80°C is set as E1_80, the thickness of the base material is set as d1 (mm), the Young's modulus of the skin layer at 80°C is set as E2_80 (Gpa), and the thickness is set as d2 (mm), it is configured to satisfy the following relationships of Expression (1) and Expression (2).[Number 1][Number 2]

Description

TECHNICAL FIELD

[0001] The present application relates to a vehicle interior material and a seat back panel using the same. BACKGROUND

[0002] A molded product that can be used as a seat back of a vehicle is described in Patent Literature 1. The molded product of Patent Literature 1 is a product in which a skin is fixed to a nonwoven fabric by an adhesive layer, and it is described in Patent Literature 1 that natural leather, synthetic leather, or fabric is used as the skin.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2020-121551 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] In a material used as a vehicle interior material such as a seat back panel, it is desirable to balance the strength as an interior material and the high-class feeling of the appearance. However, the molded product described in Patent Literature 1 aims at easiness of sewing and securing of strength, and does not aim at improving the high-class feeling of the appearance, and there is room for improvement in this regard.

[0008] An object of the present application is to solve the above-described problem, and to provide a vehicle interior material improved in a manner in which good appearance and sufficient strength can be balanced, and a seat back panel formed using the same.

[0009] MEANS FOR SOLVING THE PROBLEM

[0010] One example of the vehicle interior material in the present application is a laminated structure body including at least a base material and a skin layer. When the average of the surface roughness of the base material in the horizontal direction is set as RSm (mm), the Young's modulus of the base material at 80°C is set as E1_80, the thickness of the base material is set as d1 (mm), the Young's modulus of the skin layer at 80°C is set as E2_80 (Gpa), and the thickness is set as d2 (mm), it is configured to satisfy the following relationships of Expression (1) and Expression (2).

[0011] [Num 1]

[0012]

[0013] [Num 2]

[0014]

[0015] The seat back panel according to another aspect of the present application is formed using the vehicle interior material according to any one aspect of the present application.

[0016] Inventive Effects

[0017] According to one example of the interior material for a vehicle of the present application, the thickness of the skin layer is adjusted according to the surface roughness of the base material within a range in which sufficient strength can be ensured by the base material. Thus, the interior material for a vehicle can have a good appearance while ensuring sufficient strength. In addition, by using a seat back panel formed using the interior material for a vehicle for a seat of a vehicle, the space inside the vehicle can have a high-class feel. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a view schematically showing a seat arranged in a vehicle.

[0019] Figure 2 is a view schematically showing a cross-sectional configuration of the interior material for a vehicle of Embodiment 1 of the present application.

[0020] Figure 3 is a view schematically showing a relationship between the average (mm) of the surface roughness of the base material of the interior material for a vehicle of Embodiment 1 of the present application in the horizontal direction and the thickness (mm) of the skin layer.

[0021] Figure 4 is a view showing a relationship between the height of the concave-convex of the interior material for a vehicle of Embodiment 1 of the present application and the ratio of the average of the surface roughness of the base material in the horizontal direction to the thickness of the skin layer.

[0022] Figure 5 is a view showing a calculation method of the average RSm of the surface roughness of the base material in the horizontal direction.

[0023] Figure 6 shows a specific sample example of the interior material for a vehicle of Embodiment 1 of the present application.

[0024] Figure 7 is a view schematically showing a cross-sectional configuration of the interior material for a vehicle of Embodiment 3 of the present application. DETAILED DESCRIPTION

[0025] Embodiments of the interior material for a vehicle of the present application will be described below with reference to the drawings. Note that in each drawing, the same or equivalent parts are denoted by the same reference signs, and the description thereof will be simplified or omitted.

[0026] Embodiment 1.

[0027] Figure 1 is a view showing an example of a seat arranged in a vehicle. The interior material for a vehicle 10 of the present embodiment is, for example, as shown in Figure 1The material shown is used as a seat back plate 2 of a seat 1 for a vehicle. The seat back plate 2 is located in a conspicuous position in front of a person seated on a rear seat, and occupies a large area in a vehicle cabin. Therefore, by applying the vehicle interior material 10 of the present embodiment to the seat back plate 2, the appearance of the vehicle cabin space can be effectively given a high-class feel.

[0028] However, the vehicle interior material 10 can also be appropriately used for other components provided in a vehicle, particularly, a portion touched by a person's hand or a portion easily seen by a person's eye. Specifically, the vehicle interior material 10 can be used as a material constituting, for example, an entire or a part of an instrument panel, a meter panel, a door trim, a center pillar trim, and a rear parcel shelf, in addition to being used as a material constituting a seat back plate.

[0029] Figure 2 is a view schematically showing a cross-sectional configuration of the vehicle interior material of the present embodiment. As shown in Figure 2 The vehicle interior material 10 is a laminated structure in which a base material 11 and a skin layer 12 are bonded.

[0030] The base material 11 is made of a comparatively light material adjusted in a ratio in a manner that necessary rigidity can be ensured, and the base material 11 is used to ensure sufficient strength of the interior component for a vehicle. In addition, the base material 11 is formed of a material that is at least lighter (smaller in density) than the skin layer 12. Specifically, as the material of the base material 11, for example, felt such as fiber, compressed felt, and stitch-bonded felt, or a foamed resin such as foamed polyurethane, and a hollow structure of a resin such as a honeycomb structure are used. In addition, the base material 11 can be configured in a laminate of felt and a resin or the like.

[0031] The skin layer 12 is, for example, made of synthetic leather containing PVC (polyvinyl chloride). Here, the synthetic leather containing PVC includes synthetic leather made of only PVC, and synthetic leather in which PVC is a main component. The synthetic leather in which PVC is a main component includes, for example, synthetic leather in which a resin such as nylon or polyurethane is coated on the surface of PVC. In addition, the skin layer 12 can be made of, for example, synthetic leather containing other materials such as PP (polypropylene), fibers such as nonwoven fabric and fabric, and natural leather. By using these materials, the appearance of the vehicle interior material 10 can be given a high-class feel.

[0032] Figure 3 is a view schematically showing a relationship between the average RSm (mm) of the surface roughness of the base material 11 of the vehicle interior material 10 in the horizontal direction and the thickness d2 (mm) of the skin layer 12. Figure 3In the figure, the vertical axis represents the average surface roughness RSm of the substrate 11 in the horizontal direction, and the horizontal axis represents d2×E2_80, which is obtained by multiplying the thickness d2 of the skin layer 12 by the Young's modulus E2_80 of the material constituting the skin layer 12 at 80°C. It should be noted that in the following embodiments, the average surface roughness of the substrate 11 in the horizontal direction will also be simply referred to as the "roughness average". In the vehicle interior material 10 of this embodiment, the relationship between the roughness average RSm and the thickness d2 of the skin layer 12 is adjusted so that it is included in the... Figure 3 The solid lines A and B are sandwiched in the middle area.

[0033] Figure 3 The solid line A represents the relationship between the average roughness RSm, set considering the allowable weight, and the thickness d2 of the skin layer 12. If the thickness d2 of the skin layer 12 is too thick relative to the substrate 11, although a smooth appearance can be ensured, the overall thickness increases, leading to an increase in the weight of the component formed from the vehicle interior material 10. In Embodiment 1, the solid line A, serving as the lower limit, is determined considering the thickness and weight of existing PP, and the vehicle interior material 10 is made into an interior material that is at least lighter than that of PP.

[0034] Figure 3 The solid line B represents the relationship between the average roughness RSm, set to the target of roughness of the appearance of the vehicle interior material 10, and the thickness d2 of the skin layer 12, in Embodiment 1. Both the surface roughness of the substrate 11 and the thickness of the skin layer 12 affect the size of the unevenness appearing on the appearance of the vehicle interior material 10. To ensure a smooth surface for the vehicle interior material 10, the larger the average roughness RSm, the greater the thickness d2 of the skin layer 12 needs to be. Figure 3 On the side where the average roughness RSm is larger than that of solid line B, the roughness of substrate 11 cannot be fully concealed by skin layer 12. As a result, the interior material 10 for vehicles exhibits obvious unevenness and lacks a premium feel. Therefore, in this embodiment, the interior material 10 for vehicles is designed with an average roughness RSm that is proportionally smaller than that of solid line B.

[0035] Figure 4 This is a graph showing the relationship between the average height Rz of the surface unevenness of the vehicle interior material 10 and the following ratio, which is the ratio of the average roughness RSm of the substrate 11 to the thickness d2×80°C and Young's modulus E2_80 of the skin layer. Figure 4As shown, in Embodiment 1, a target is set such that the height average Rz (mm) of the concave-convex of the surface of the vehicle interior material 10 is less than 0.04 (mm). Also, in correspondence with this target, the upper limit value of the ratio of the roughness average to the thickness of the skin layer 12 (a2 = RSm / (d2 x E2_80)) is set to 135.

[0036] Specifically, the vehicle interior material 10 of the present embodiment is configured such that the roughness average RSm (mm) and the thickness d2 (mm) of the skin layer 12 satisfy the following equation (3).

[0037] [Equation 3]

[0038]

[0039] Note that the Young's modulus E2_80 of the skin material of the skin layer 12 at 80°C is in correspondence with the maximum temperature 80°C of the thermal cycle test, because by defining the thickness d2 in the state in which the skin is the softest, sufficient surface smoothness can be ensured even in the most severe high-temperature environment. Also, in the case where the skin layer 12 is a hollow structure or the like, the Young's modulus can sometimes be anisotropic. In this case, the Young's modulus in any one of the different directions is used.

[0040] Also, the roughness average RSm used in each equation is a value calculated based on the definition prescribed in "JIS B 0601 (ISO 4287)". Figure 5 is a graph showing the calculation method of the roughness average RSm of the base material 11. As shown in Figure 5 the roughness average RSm is calculated from the following equation (4).

[0041] [Equation 4]

[0042]

[0043] The roughness average RSm is a value indicating the average of the lengths Xsi of the profile curve elements in the reference length. The peak and valley constituting the profile elements here have a prescribed minimum height and minimum length, and a height or depth of 10% or less of the maximum height, or a length of 1% or less of the length of the calculation zone, is regarded as noise and considered to be part of a peak that continues forward and backward.

[0044] Further, as a seat back plate of a conventional vehicle, for example, one formed by injection molding of PP (polypropylene) is known. However, a component formed of PP is hard to the touch and the surface has a rough feel. Therefore, PP is used as a vehicle interior material, and when the exposed portion of PP in the vehicle interior increases, the luxury of the vehicle cabin space decreases. Further, in the case of a relatively large component such as a seat back formed of PP, a certain degree of plate thickness is required, and thus the component becomes heavy, but since the strength of the component and the retention of the shape need to be ensured, the plate thickness of the PP cannot simply be reduced for the purpose of weight reduction. Generally, in order to balance the weight reduction and the strength of a component composed of PP, a countermeasure of providing a plurality of ribs or the like on the inner side of the component is taken, but there is a limit to weight reduction.

[0045] On the other hand, in the vehicle interior material 10 of the present embodiment, the base material 11 is composed of a lightweight material capable of ensuring strength, and the surface of the base material 11 is covered with the skin layer 12 having a sufficient thickness corresponding to the roughness average RSm of the base material 11, while suppressing the overall weight within an allowable range. Thus, the vehicle interior material 10 is lightweight, has a good appearance, and can ensure sufficient strength.

[0046] Figure 6 A specific sample example of the vehicle interior material 10 of the present embodiment is shown. Hereinafter, the following Figure 6 A specific example of the present embodiment is shown. Note that, Figure 6 In Table 1, the top row of the table shows the values of the interior material composed of a single layer of PP as a comparative example.

[0047] Example 1.

[0048] Sample 1 is a vehicle interior material 10 using a felt having a roughness average RSm = 0.62 (mm) as the base material 11 and PP having a thickness d2 = 2.5 (mm) as the skin layer 12. The Young's modulus E2_80 of the skin layer 12 is 1520 (MPa). The a1 = RSm / (E2_80 x d2) of Sample 1 is 0.163, and Sample 1 is a vehicle interior material 10 satisfying the formula (3).

[0049] Example 2.

[0050] Sample 2 is a vehicle interior material 10 using a felt having a roughness average RSm = 0.905 (mm) as the base material 11 and PVC having a thickness d2 = 1.22 (mm) as the skin layer 12. The Young's modulus E2_80 of the skin layer 12 is 6.3 (MPa). The a1 = RSm / (E2_80 x d2) of Sample 2 is 124.2, and Sample 2 is a vehicle interior material 10 satisfying the relationship of the formula (3).

[0051] Example 3.

[0052] Sample 3 is a vehicle interior material 10 using felt having a roughness average RSm = 0.62 (mm) as the base material 11, using fiber having a thickness d2 = 0.42 (mm) as the skin layer 12. The Young's modulus E2_80 of the skin layer 12 is 107.5 (MPa). The a1 = RSm / (E2_80 x d2) of Sample 3 is 13.73, and Sample 3 is a vehicle interior material 10 satisfying the relationship of the formula (3).

[0053] Example 4.

[0054] Sample 5 is a vehicle interior material 10 using foamed polyurethane having a roughness average RSm = 1.15 (mm) as the base material 11, using PVC having a thickness d2 = 1.22 (mm) as the skin layer 12. The Young's modulus E2_80 of the skin layer 12 is 6.3 (MPa). The a1 = RSm / (E2_80 x d2) of Sample 5 is 121.2, and Sample 5 is a vehicle interior material 10 satisfying the relationship of the formula (3).

[0055] Note that Sample 4 is a vehicle interior material 10 using felt having a roughness average RSm = 1.22 (mm) as the base material 11, using PVC having a thickness d2 = 1.11 (mm) as the skin layer 12. The Young's modulus E2_80 of the skin layer 12 is 7.6 (MPa). The a1 = RSm / (E2_80 x d2) of Sample 4 is 160, and Sample 4 does not satisfy the relationship of the formula (3), and is not a vehicle interior material 10 of the present embodiment.

[0056] Embodiment 2.

[0057] The vehicle interior material 10 of Embodiment 2 is also a laminated structure in which the base material 11 having a thickness d1 and the skin layer 12 having a thickness d2 are laminated, like the vehicle interior material 10 of Embodiment 1. In Embodiment 1, the relationship between the thickness d2 of the skin layer 12 and the roughness average RSm of the base material 11 is defined, and in contrast, in the vehicle interior material 10 of Embodiment 2, the relationship between the total thickness (d1 and d2) and the roughness average RSm of the base material 11 is defined.

[0058] Specifically, in the vehicle interior material 10 of Embodiment 2, the relationship between the roughness average RSm of the base material 11 and the thickness (d1 and d2) of each layer is defined according to the following formula (5).

[0059] [Num 5]

[0060]

[0061] The base material 11 and the skin layer 12 of the vehicle interior material 10 are essential constituent elements, and therefore the thicknesses d1 and d2 are values of at least greater than 0. In addition, E1_80 and E2_80 are the Young's moduli of the base material 11 and the skin layer 12 at 80°C, respectively. As described also in Embodiment 1, in the case where the base material 11 or the skin layer 12 is a hollow structure or the like, the Young's modulus can sometimes be anisotropic. In this case, the Young's modulus in any one of the different directions is used.

[0062] Note that the vehicle interior material 10 of Embodiment 2 is the same as Embodiment 1 except that the base material 11 and the skin layer 12 satisfy the above-described relationship of formula (5), and therefore the description of the constituent materials and the uses of each layer and the like described in Embodiment 1 can be directly applied to the vehicle interior material 10 of Embodiment 2. In the case where the relationship of the base material 11 and the skin layer 12 is defined in accordance with formula (5), a vehicle interior material 10 having a good appearance and a light weight can also be obtained as in the case of Embodiment 1.

[0063] Embodiment 3.

[0064] Figure 7 is a view schematically showing the constitution of the vehicle interior material 30 of Embodiment 3. As shown in the view, the vehicle interior material 30 has an intermediate layer 13 between the base material 11 and the skin layer 12. The intermediate layer 13 is provided for the adhesion of the base material 11 and the skin layer 12 and the reinforcement of the vehicle interior material 30. As the intermediate layer 13, a nonwoven fabric, a fiber, PP, or the like is used. Figure 7

[0065] When the thickness of the skin layer 12 is d2, the thicknesses of the n layers (n is a natural number of 1 or more) of the intermediate layer 13 are respectively dMn (mm), the Young's modulus of the skin layer 12 at 80°C is E2_80, and the Young's modulus of the n layers of the intermediate layer 13 at 80°C is EMn_80 (Gpa), the vehicle interior material 30 of Embodiment 3 is constituted so that the average roughness RSm of the base material 11 and the thicknesses dMn of the intermediate layer 13 and the thickness d2 of the skin layer 12 satisfy the following formula (6).

[0066] [Formula 6]

[0067]

[0068] Note that, as in the case of the base material 11 and the skin layer 12, in the case where the intermediate layer 13 is a hollow structure or the like and the Young's modulus thereof is anisotropic, the Young's modulus in any one of the different directions is used as EMi_80.

[0069] ​When the vehicle interior material 30 is configured to have the intermediate layer 13, by being configured as described above in the formula (6) that takes into account the thickness d3 of the intermediate layer 13 and the thickness d2 of the skin layer 12, it is possible to obtain a vehicle interior material 30 that is good in appearance, light in weight, and high in strength, as in Embodiments 1 and 2.

[0070] Note that the vehicle interior material 30 can also be configured so that the thickness d3 of the intermediate layer 13, the roughness average RSm of the base material 11, and the thickness d2 of the skin layer 12 satisfy the relationship of the formula (3). By being configured so as to satisfy the relationship of the formula (3), it is possible to make the vehicle interior material 30 a material that is good in appearance and light in weight, and high in strength, as in the case of Embodiment 1.

[0071] Alternatively, the vehicle interior material 30 can be adjusted so that the thicknesses of all of the n intermediate layers 13, the thickness d2 of the skin layer 12, and the thickness d1 of the base material 11 satisfy the relationship of the following formula (7) with respect to each thickness and the roughness average RSm.

[0072] [Num 7]

[0073]

[0074] Other Embodiments

[0075] Here, in the case where the vehicle interior material 10 is configured of the two layers of the base material 11 and the skin layer 12, the thickness of the base material 11 is set to d1, the thickness of the skin layer 12 is set to d2, and a1, a2 are values indicated by the following formulas (8) and (9) corresponding to the above formulas (3) and (5).

[0076] [Num 8]

[0077]

[0078] [Num 9]

[0079]

[0080] In Embodiment 1, the case where a1 satisfies the relationship of the formula (3) (0.15 < a < 135) was described, and in Embodiment 2, the case where a2 satisfies the relationship of the formula (5) (0.15 < a2 < 135) was described. However, it is sufficient for the vehicle interior material 10 to be adjusted so as to satisfy the relationship of at least 0.15 < a1 and a2 < 135 with respect to the relationship of the base material 11 and the skin layer 12.

[0081] Further, the vehicle interior material 10 is more preferably adjusted in such a manner that the relationship of 0.15 < α2 and α1 < 135 is satisfied. Since α1 > α2, by making 0.15 < α2 and α1 < 135, the relationship of 0.15 < α2 < α1 < 135 is established. Thus, the vehicle interior material 10 having a more excellent appearance satisfying both the relationship of formula (3) of Embodiment 1 and formula (5) of Embodiment 2 can be obtained.

[0082] Further, in the case where the vehicle interior material 30 is composed of three or more layers of the substrate 11, the skin layer 12, and the n layers of the intermediate layer 13, the thickness of the substrate 11 is set to d1, the thickness of the skin layer 12 is set to d2, and the thickness of the intermediate layer 13 is set to dMn, and α1 is defined in accordance with the above formula (8) corresponding to the above formula (3), and α3 and α4 are made to be the values shown in the following formulae (10) and (11) corresponding to the formulae (6) and (7) explained in Embodiment 3, respectively.

[0083] [Numeral 10]

[0084]

[0085] [Numeral 11]

[0086]

[0087] In formula (6) of Embodiment 3, the case where the substrate roughness average RSm is adjusted in such a manner that the relationship of 0.15 < α3 < 135 is satisfied, and the thicknesses of the skin layer 12 and the intermediate layer 13 are explained. However, the vehicle interior material 30 can be adjusted in such a manner that at least the relationship of 0.15 < α1 and α4 < 135 is satisfied.

[0088] Further, the vehicle interior material 30 can be adjusted in such a manner that the relationship of 0.15 < α1 and α3 < 135 is satisfied, or in such a manner that the relationship of 0.15 < α3 and α4 < 135 is satisfied.

[0089] More preferably, the layers 11 to 13 can be adjusted in such a manner that the relationship of 0.15 < α4 and α1 < 135 is satisfied. Since α1 > α3 > α4, by making 0.15 < α4 and α1 < 135, the relationship of 0.15 < α4 < α3 < α1 < 135 is established, and the vehicle interior material 30 satisfying both formula (6) and formula (7) of Embodiment (3) and having a more excellent appearance can be obtained.

[0090] Note that in the above-described embodiments, in the case where a numerical value is mentioned with respect to the number, quantity, amount, range, or the like of each element, the present application is not limited to the mentioned numerical value except for the case where it is particularly indicated or clearly determined as the numerical value in principle. In addition, with respect to the structure and the like described in the present embodiment, it is not necessarily required in the present application except for the case where it is particularly indicated or clearly determined as such in principle.

[0091] Symbol explanation

[0092] 1 seat

[0093] 2 seat back plate

[0094] 10, 30 interior material for vehicle

[0095] 11 base material

[0096] 12 skin layer

[0097] 13 intermediate layer

Claims

1. A vehicle interior material, comprising at least a substrate and a skin layer, characterized in that, Let the average surface roughness of the substrate in the horizontal direction be RSm, the Young's modulus of the substrate at 80°C be E1_80, and the thickness of the substrate be d1. When the Young's modulus of the skin layer at 80°C is set to E2_80 and the thickness of the skin layer is set to d2, The configuration is such that it satisfies the following relationships (1) and (2), where RSm, d1, and d2 are in mm, and E1_80 and E2_80 are in GPa.

2. The vehicle interior material as described in claim 1, characterized in that, The interior materials used in the vehicle are configured to further satisfy the relationship of the following equation (3).

3. A vehicle interior material, which is a laminated structure comprising at least a substrate and a surface layer, characterized in that, Let the average surface roughness of the substrate in the horizontal direction be RSm. When the Young's modulus of the skin layer at 80°C is set to E2_80 and the thickness of the skin layer is set to d2, The structure is configured to satisfy the following relationship (4), where RSm and d2 are in mm, and E2_80 is in GPa.

4. The vehicle interior material as described in any one of claims 1 to 3, characterized in that, The substrate is formed from fibers, felt, and foamed resin.

5. The vehicle interior material as described in any one of claims 1 to 3, characterized in that, The substrate is formed from a hollow resin structure.

6. The vehicle interior material as described in any one of claims 1 to 3, characterized in that, The outer layer is formed of synthetic leather, non-woven fabric, textile or natural leather.

7. The vehicle interior material as described in any one of claims 1 to 3, characterized in that, A single-layer or multi-layer intermediate layer is further provided between the skin layer and the substrate.

8. The vehicle interior material as described in claim 7, wherein, The intermediate layer comprises a layer formed from any one of nonwoven fabric, resin sheet, fiber, and polypropylene.

9. The vehicle interior material as described in claim 7, characterized in that, When the intermediate layer has n layers When the Young's modulus of the intermediate layer at 80°C is set to EMn_80 and the thickness is set to dMn, the structure satisfies the following relationship (5), where the unit of EMn_80 is GPa and the unit of dMn is mm.

10. The vehicle interior material as described in claim 7, characterized in that, When the intermediate layer has n layers When the Young's modulus of the substrate at 80°C is set as E1_80, the thickness of the substrate is set as d1, the Young's modulus of the intermediate layer at 80°C is set as EMn_80, and the thickness is set as dMn, the structure satisfies the following relationship (6), where the units of E1_80 and EMn_80 are GPa, and the units of d1 and dMn are mm.

11. A seat back panel formed using any one of the vehicle interior materials claimed in claims 1 to 10.

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