Vehicle interior material and method for producing vehicle interior material

Abstract

The object is to provide a vehicle interior material and a method for manufacturing a vehicle interior material that can effectively remove unpleasant odors and VOCs. The vehicle interior material of the present invention is characterized in that it comprises an interior base material and a fibrous activated carbon sheet laminated on the surface of the interior base material via a hot melt film, the hot melt film is provided with at least one of a through hole and a crack, and the interior base material and the fibrous activated carbon sheet are integrated by welding the hot melt film.

Description

Technical Field

[0001] The present invention relates to a vehicle interior material and a method for producing the vehicle interior material. Background Art

[0002] Conventionally, measures have been required to control unpleasant odors such as exhaust odor, fuel odor, tobacco odor, body odor, and the odor of rotting food waste, including material odors generated from interior resin parts such as seat cushions, etc. In addition, measures have also been required to control VOCs (volatile organic compounds) generated from painted parts such as instrument panels and door trims.

[0003] As a countermeasure against unpleasant odors and VOCs, methods of using adsorbents such as activated carbon sheets in vehicle interior materials are known. In the conventional method of using activated carbon sheets in vehicle interior materials, after the substrate of the vehicle interior material is formed, the activated carbon sheet is attached to the substrate by sewing or attaching with a transparent tape, and post-forming processing is required. In addition, conventional activated carbon sheets are specifications in which powdered activated carbon is impregnated in non-woven fabrics, etc., and have no conformability, so it is difficult to be integrally formed with the substrate.

[0004] In order to deal with these problems, such as the deodorizing interior material for passenger vehicles described in Patent Document 1, a vehicle interior material is known, which uses a flexible fibrous activated carbon sheet as an activated carbon sheet, stacks the activated carbon sheets on the surface of the substrate with an adhesive layer to obtain a laminate, and the laminate is formed in one piece. This vehicle interior material can be manufactured by using the inherent forming molds and existing equipment used in the forming process of various vehicle interior materials such as floor mats (carpets, face guards) and roof linings, so there is no need for additional equipment investment, and there is no need for subsequent processing after forming such as sewing and attaching. Therefore, countermeasures against unpleasant odors and VOCs can be achieved at a low cost.

[0005] Prior art documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2002-126511 Summary of the invention

[0007] In conventional vehicle interior materials in which an activated carbon sheet is laminated on a substrate surface with an adhesive and formed integrally, the adhesive surface of the activated carbon sheet is covered with the adhesive, thereby reducing air permeability. As a result, there is a fear that the activated carbon sheet cannot effectively absorb unpleasant odors and VOCs.

[0008] The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle interior material and a method for producing a vehicle interior material that can effectively remove unpleasant odors and VOCs.

[0009] In order to solve the above-mentioned problems, the vehicle interior material of the present invention is characterized in that it has an interior base material and a fibrous activated carbon sheet laminated on the surface of the above-mentioned interior base material via a hot-melt film, the above-mentioned hot-melt film is provided with at least one of a through hole and a crack, and the above-mentioned interior base material and the above-mentioned fibrous activated carbon sheet are integrated by welding the above-mentioned hot-melt film.

[0010] In addition, the manufacturing method of the vehicle interior material of the present invention is a method for manufacturing the vehicle interior material obtained by integrating the interior substrate and the fibrous activated carbon sheet, which is characterized by comprising a lamination step and an integration step, wherein the lamination step is to obtain a laminated body by laminating the fibrous activated carbon sheet on the surface of the interior substrate via a hot melt film, and the hot melt film is provided with at least one of a through hole and a crack, and the integration step is to press the laminated body into shape, and integrate the interior substrate and the fibrous activated carbon sheet of the laminated body by welding the hot melt film.

[0011] According to the present invention, unpleasant odors and VOCs can be effectively removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] 1( a ) is a schematic cross-sectional view showing a vehicle interior material according to a first embodiment, and FIG. 1( b ) is a schematic plan view showing a hot-melt film welded to an outer surface of an interior base material in the vehicle interior material according to the first embodiment.

[0013] Figure 2(a) to Figure 2(f) It is a schematic cross-sectional view showing the process of manufacturing the vehicle interior material according to the first embodiment.

[0014] Figure 3(a) is a schematic plan view of the fibrous activated carbon sheet and hot-melt film of the stack obtained in the lamination step of the manufacturing method of the vehicle interior material of the first embodiment, looking down from the hot-melt film side, and Figure 3(b) is a schematic cross-sectional view of the stack along the AA line of Figure 3(a).

[0015] Figure 4(a) is a schematic plan view of the fibrous activated carbon sheet and hot melt film of the stacked body obtained in the lamination step of the manufacturing method of the vehicle interior material of the modified example of the first embodiment, looking down from the hot melt film side, and Figure 4(b) is a schematic cross-sectional view of the stacked body along the AA line of Figure 4(a).

[0016] Figure 5(a) to Figure 5(d) This is a photograph showing another example of the vehicle interior material according to the embodiment.

[0017] Figure 6(a) and 6(b) This is a photograph showing another example of the hot-melt film according to the embodiment.

[0018] Figure 7(a) to Figure 7(c) This is a photograph showing the through-holes of another example of the hot-melt film according to the embodiment.

[0019] Fig. 8(a) is a photograph of the appearance of the fibrous activated carbon sheet side of the package tray manufactured in the example. Fig. 8(b) is a graph showing the average values ​​of the evaluation results of the odor intensity and discomfort (unpleasantness) and the odor intensity of the unique odor of the package tray of the example (with activated carbon) and the comparison object (without activated carbon) of the internal substrate.

[0020] Fig. 9(a) is a graph showing the average values ​​of the evaluation results of the odor intensity of the unique odor of the reference example activated carbon integrated floor covering and the comparison object conventional floor covering. Fig. 9(b) is a graph showing the amount of aldehydes per test piece in the air bag measured for the reference example activated carbon integrated floor covering and the comparison object conventional floor covering, and Fig. 9(c) is a graph showing the amount of other hydrocarbons per test piece in the air bag measured for the reference example activated carbon integrated floor covering and the comparison object conventional floor covering.

[0021] Description of Reference Numerals

[0022] 2 interior base material

[0023] 2s Outer surface

[0024] 2sa upper surface of surface convex part

[0025] 2sb Side of the convex part of the surface

[0026] 4 Hot melt film

[0027] 4h Through hole

[0028] 4n Gap

[0029] 4d Rift

[0030] 6 Fibrous activated carbon sheets

[0031] 10 Vehicle interior materials

[0032] 10p stack DETAILED DESCRIPTION

[0033] Hereinafter, embodiments of the vehicle interior material and the method for producing the vehicle interior material of the present invention will be described.

[0034] First, the overview of the vehicle interior material and the method for producing the vehicle interior material according to the embodiments will be described by taking the vehicle interior material and the method for producing the vehicle interior material according to the first embodiment as an example.

[0035] (Vehicle interior material according to first embodiment)

[0036] 1( a ) is a schematic cross-sectional view showing a vehicle interior material according to a first embodiment, and FIG. 1( b ) is a schematic plan view showing a hot-melt film welded to an outer surface of an interior base material in the vehicle interior material according to the first embodiment.

[0037] As shown in Fig. 1(a) and Fig. 1(b), the vehicle interior material 10 of the first embodiment is a floor covering, which comprises: an interior substrate 2 and a fibrous activated carbon sheet 6 laminated on the outer surface 2s of the interior substrate 2 via a hot melt film 4. The outer surface 2s of the interior substrate 2 has a concave portion and a convex portion. As the hot melt film 4, a notch 4n is provided at the outer edge 4e, and a through hole 4h is provided on the inner side. The hot melt film 4 is welded to the upper surface 2sa and the side surface 2sb of the convex portion of the outer surface 2s of the interior substrate 2. The hot melt film 4 is welded to the inner surface 6r of the fibrous activated carbon sheet 6. The interior substrate 2 and the fibrous activated carbon sheet 6 are integrated by welding the hot melt film 4.

[0038] In the vehicle interior material 10 of the first embodiment, the hot melt film 4 that fuses the interior base material 2 and the fibrous activated carbon sheet 6 is provided with a notch 4n and a through hole 4h. Therefore, the air permeability between the interior base material 2 and the fibrous activated carbon sheet 6 can be ensured by the notch 4n and the through hole 4h of the hot melt film 4. As a result, in addition to the unpleasant odor and VOC generated in the interior base material 2, the unpleasant odor and VOC, etc. that reach the hot melt film 4 from the outside through the interior base material 2 can be effectively absorbed by the fibrous activated carbon sheet 6. Therefore, the unpleasant odor and VOC, etc. can be effectively removed.

[0039] (Method for Manufacturing Vehicle Interior Material According to First Embodiment)

[0040] Figure 2(a) to Figure 2(f) 3(a) is a schematic plan view of the fibrous activated carbon sheet and the hot melt film of the laminate obtained in the lamination process of the method for manufacturing the vehicle interior material of the first embodiment, viewed from the hot melt film side, and FIG. 3(b) is a schematic cross-sectional view of the laminate along the AA line of FIG. 3(a).

[0041] In the method for manufacturing the vehicle interior material of the first embodiment, first, as shown in FIG. 2(a), the interior base material 2 is prepared by unwinding from a roll R (preparation step). Then, a predetermined fibrous activated carbon sheet 6 to be integrated with the interior base material 2 and a hot melt film 4 for integrating the two are prepared. Next, as shown in FIG. 2(b), the fibrous activated carbon sheet 6 is laminated on the outer surface 2s of the interior base material 2 via the hot melt film 4 to obtain a laminated body 10p (lamination step).

[0042] As shown in Fig. 3 (a) and Fig. 3 (b), the hot melt film 4 is a multilayer structure film in which an inner welding layer 4a, a heat-resistant layer 4b and an outer welding layer 4c are sequentially stacked. In the laminate 10p, the inner surface 4ar of the inner welding layer 4a (the inner surface 4r of the hot melt film 4) contacts the outer surface 2s of the inner substrate 2, and the outer surface 4cs of the outer welding layer 4c (the outer surface 4s of the hot melt film 4) contacts the inner surface 6r of the fibrous activated carbon sheet 6. As shown in Fig. 3 (a), when the fibrous activated carbon sheet 6 and the hot melt film 4 of the laminate 10p are viewed from the hot melt film side, the outer edge 6e of the fibrous activated carbon sheet 6 is rectangular, and the outer edge 4e of the hot melt film 4 overlaps with the outer edge 6e of the fibrous activated carbon sheet 6 except for the notch 4n. As the hot melt film 4, a plurality of partially circular notches 4n are arranged on the outer edge 4e, and a plurality of circular through holes 4h are arranged on the inner side in the longitudinal and transverse directions.

[0043] Next, as shown in Figures 2(c) and 3(b), after the laminate 10p is placed in a heating furnace, the laminate 10p is heated in the heating furnace to a temperature at which the inner welding layer 4a and the outer welding layer of the hot melt film 4 melt and exhibit adhesive strength, but does not reach a temperature at which the heat-resistant layer 4b of the hot melt film 4 melts and exhibits adhesive strength (heating process).

[0044] Next, as shown in FIG. 2( d ), the heated laminate 10 p is arranged between the upper mold and the lower mold of the forming mold, and is pressed and formed by the forming mold (forming process). Thus, the inner base material 2 of the laminate 10 p is formed into the shape of the mold surface, and the outer surface 2s and the inner surface 2r of the inner base material 2 are formed into a shape having a concave portion and a convex portion. At the same time, the fibrous activated carbon sheet 6 and the hot melt film 4 are compressed between the upper mold of the forming mold and the inner base material 2, so that they are deformed into the shape of the convex portion along the outer surface 2s of the inner base material 2. Then, the inner fusion layer 4 a (shown in FIG. 3( b )) and the outer fusion layer 4 c (shown in FIG. 3( b )) of the hot melt film 4 are respectively fused to the convex portion of the outer surface 2s of the inner base material 2 and the inner surface 6r of the fibrous activated carbon sheet 6. Furthermore, at this time, the inner fusion layer 4 a and the outer fusion layer 4 c are also fused to the heat-resistant layer 4 b (shown in FIG. 3( b )) located between them. In this way, the internal base material 2 and the fibrous activated carbon sheet 6 of the laminate 10p are integrated by welding the hot-melt film 4 (integration step).

[0045] Next, as shown in FIG2(e), the integrated laminate 10p is arranged between the upper die and the lower die of the punching die, and is cut by the punching die so that the outer edge when viewed from the stacking direction becomes the desired shape (cutting process). Thus, as shown in FIG2(f), the vehicle interior material 10 is manufactured. Furthermore, the vehicle interior material 10 shown in FIG2(f) is the same as the vehicle interior material 10 shown in FIG1, but as required, as shown in FIG2(f), a sound absorbing material 20 is arranged on the outer surface side of the vehicle interior material 10 and then installed on the vehicle.

[0046] In the method for manufacturing the vehicle interior material of the first embodiment, the hot melt film 4 between the interior base material 2 and the fibrous activated carbon sheet 6 of the laminate 10p is provided with a notch 4n and a through hole 4h. Therefore, when the heated laminate 10p is press-formed and the fibrous activated carbon sheet 6 and the hot melt film 4 are compressed between the upper mold of the forming mold and the interior base material 2 and deformed into the shape of the convex portion along the outer surface 2s of the interior base material 2, the followability of the hot melt film 4 can be improved, and the formation of wrinkles and uneven welding of the hot melt film 4 can be suppressed. In addition, the vehicle interior material 10 that can effectively remove unpleasant odors and VOCs can be manufactured.

[0047] (Variation Example)

[0048] Figure 4(a) is a schematic plan view of the fibrous activated carbon sheet and hot melt film of the stacked body obtained in the lamination step of the manufacturing method of the vehicle interior material of the first embodiment variant, looking down from the hot melt film side, and Figure 4(b) is a schematic cross-sectional view of the stacked body along the AA line of Figure 4(a).

[0049] like Figure 4(a) and 4(b) As shown, in the laminated body 10p obtained in the lamination process of the modified example, the hot melt film 4 is a single-layer structure film composed of a single fusion layer. In the laminated body 10p, the inner surface 4r of the hot melt film 4 contacts the outer surface 2s of the interior substrate 2, and the outer surface 4s of the hot melt film 4 contacts the inner surface 6r of the fibrous activated carbon sheet 6. As shown in Figure 4 (a), when the fibrous activated carbon sheet 6 and the hot melt film 4 are viewed from the side of the hot melt film, the outer edge 6e of the fibrous activated carbon sheet 6 is rectangular, and the outer edge 4e of the hot melt film 4 overlaps with the outer edge 6e of the fibrous activated carbon sheet 6 except for the notch 4n. As the hot melt film 4, a notch 4n is provided at the corner 4g, and a cross-shaped crack 4d is provided on the inside. The laminated body 10p shown in Figure 4 is the same as the laminated body 10p shown in Figure 3 except for the hot melt film 4.

[0050] In the modified example of the first embodiment, a laminated body 10p shown in FIG. 4 is obtained, and a vehicle interior material is manufactured in the same manner as in the first embodiment except that heating and press molding are performed. Therefore, since the hot melt film 4 is provided with the notch 4n and the crack 4d, when the heated laminated body 10p is press-molded, the followability of the hot melt film 4 can be improved in the same manner as in the first embodiment, and the formation of wrinkles and uneven welding of the hot melt film 4 can be suppressed. In addition, a vehicle interior material can be manufactured in which the air permeability between the interior base material 2 and the fibrous activated carbon sheet 6 can be ensured by the notch 4n and the crack 4d of the hot melt film 4.

[0051] (Effect)

[0052] Therefore, according to the vehicle interior material of the embodiment, it is possible to effectively remove unpleasant odors and VOCs as in the first embodiment. In addition, according to the method for manufacturing the vehicle interior material of the embodiment, it is possible to manufacture the vehicle interior material that can effectively remove unpleasant odors and VOCs as in the first embodiment and its modified examples. In addition, by setting the conditions such as the shape, size, and configuration position of the through holes or cracks of the hot melt film to appropriate conditions, when the fibrous activated carbon sheet and the fibrous activated carbon sheet are deformed into the shape of the surface concave and convex parts of the interior substrate by press-forming the heated laminated body in the integration process, the followability of the hot melt film can be improved, and the formation of wrinkles and uneven welding of the hot melt film can be suppressed.

[0053] In addition, according to the embodiment, the interior substrate and the fibrous carbon sheet can be integrated by press forming in the mass production process of the existing vehicle interior material, so there is no need to change the existing mass production process in order to mass produce the vehicle interior material with activated carbon sheets, and no new expenses for additional equipment investment are generated. Therefore, mass production can be carried out with minimal additional costs. In addition, according to the embodiment, the fibrous carbon sheet can be integrated with any shape of the surface of the interior substrate, including concave parts and convex parts, so that the installation area of ​​the fibrous carbon sheet required to fully remove unpleasant odors and VOCs can be ensured. Moreover, according to the embodiment, the area of ​​the fibrous carbon sheet can be changed when the fibrous carbon sheet is stacked on the surface of the interior substrate, so that the constraints of the installation position and forming parts of the vehicle interior material can be alleviated.

[0054] Hereinafter, each configuration of the vehicle interior material and the method for producing the vehicle interior material according to the embodiment will be described in detail.

[0055] 1. Vehicle interior materials

[0056] The vehicle interior material comprises an interior base material and a fibrous activated carbon sheet laminated on the surface of the interior base material via a hot-melt film, the hot-melt film being provided with at least one of through holes and cracks, and the interior base material and the fibrous activated carbon sheet being integrated by welding the hot-melt film.

[0057] (1) Hot melt film

[0058] The hot melt film is not particularly limited as long as it has at least one of through holes and cracks, and may have only one of through holes and cracks as shown in FIG. 2( b ), or may have both. The through holes and cracks of the hot melt film correspond to the through holes and cracks after the hot melt film between the internal base material and the fibrous activated carbon sheet is welded in the lamination step of the manufacturing method of the embodiment, so the description is omitted here.

[0059] The hot melt film is not particularly limited as long as it is fused to the internal base material and the fibrous activated carbon sheet. For example, as shown in FIG. 4 described later, the hot melt film is fused to the internal base material and the fibrous activated carbon sheet by heating. It may be a single-layer structure, or a single fusion layer is fused to the internal base material and the fibrous activated carbon sheet by heating. In addition, as shown in FIG. 3, the hot melt film is fused to the internal base material and the fibrous activated carbon sheet by heating. It may also be a multi-layer structure composed of fusion layers at least at both ends in the stacking direction, and the fusion layers at both ends in the stacking direction are fused to the internal base material and the fibrous activated carbon sheet by heating.

[0060] As a multi-layer hot-melt film, such as the hot-melt film in the vehicle interior material of the first embodiment, it is preferable to arrange a heat-resistant layer between the welding layers at both ends of the stacking direction, because this can effectively improve the tracking property and suppress the formation of wrinkles and uneven welding during manufacturing.

[0061] The components of the welding layer are not particularly limited as long as they are components that can be melted by heating to exhibit adhesive strength, and examples thereof include ethylene vinyl acetate (EVA) resins, polyamide resins, polyester resins, polyolefin resins, polyurethane resins, etc. The components of the heat-resistant layer are not particularly limited as long as they are components that do not melt at a temperature at which the welding layer can be melted, and examples thereof include polyamide resins such as nylon, polyolefin resins, ethylene vinyl alcohol copolymers, polyester resins, etc.

[0062] The thickness of the hot melt film is not particularly limited. For example, in the case of a single-layer structure in which the hot melt film is composed of a fusion layer, it is preferably within a range of 30 μm to 100 μm. This is because the film thickness is above the lower limit of the range, the film itself can obtain sufficient strength, and the film thickness is below the upper limit of the range, sufficient followability can be obtained. In addition, when the hot melt film is provided with a heat-resistant layer between the fusion layers at both ends of the stacking direction, it is preferred that the thickness of the fusion layer is within a range of 10 μm to 50 μm, and the thickness of the heat-resistant layer is within a range of 10 μm to 50 μm. This is because the film itself can obtain sufficient strength when the thickness of the fusion layer is above the lower limit of the range, and sufficient followability can be obtained when the thickness of the fusion layer is below the upper limit of the range. This is because the film itself can obtain sufficient strength and can fully maintain its shape when the thickness of the heat-resistant layer is above the lower limit of the range, and sufficient followability can be obtained when the thickness of the heat-resistant layer is below the upper limit of the range.

[0063] (2) Fibrous activated carbon sheets

[0064] There is no particular limitation on the fibrous activated carbon sheet as long as it contains fibrous activated carbon (activated carbon fiber) as the main component and is formed into a sheet. For example, a certain amount of thermoplastic synthetic fiber is mixed into the fibrous activated carbon by a dry or wet method and formed into a sheet, or a plurality of such sheets are stacked and heat-treated to form an integrated whole.

[0065] The raw material of the fibrous activated carbon is not particularly limited, and examples thereof include asphalt, phenol, cellulose, acrylic, etc. Thermoplastic synthetic fibers are not particularly limited, and for example, binder fibers composed of polyester, polyamide, polyolefin, etc. can be used, and polyester binder fibers sold under the trademark MELTY from UNITIKA Co., Ltd. are particularly preferred.

[0066] The thickness of the fibrous activated carbon sheet is not particularly limited, but is preferably within a range of 600 μm to 1600 μm, because a thickness above the lower limit of the range can provide sufficient strength, and a thickness below the upper limit of the range can provide sufficient flexibility and followability.

[0067] (3) Interior base material

[0068] The interior base material is not particularly limited, and base materials generally used for vehicle interior materials can be used. For example, a base material obtained by mixing a thermoplastic resin with a fibrous material and molding the resultant material into a plate shape can be mentioned.

[0069] As fibrous materials, there can be mentioned cotton, hemp, kenaf fiber, bamboo fiber, wool, silk, glass fiber, carbon fiber, metal fiber, etc., and mixed fibers thereof, etc. As thermoplastic resins, there can be mentioned polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), nylon (PA), polystyrene, acrylonitrile-styrene copolymer, acrylate-styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, etc.

[0070] The thickness of the interior base material is not particularly limited, but is preferably in the range of 100 μm to 8000 μm, for example. This is because a thickness above the lower limit of the range can provide sufficient strength, and a thickness below the upper limit of the range can sufficiently reduce costs.

[0071] (4) Vehicle interior materials

[0072] Figure 5(a) to Figure 5(d) 5(a) shows another example of a vehicle interior material. As shown in FIG. 5(a), a vehicle interior material may be a floor covering, which includes: a covering sheet (interior base material), and a fibrous activated carbon sheet laminated on the inner surface of the covering sheet via a hot melt film on the front sheet facing area. Figure 5(b) to Figure 5(d) As shown, it may be a roof lining, a door trim, an instrument panel muffler, etc., which comprises: an interior base material, and a fibrous activated carbon sheet laminated on the surface of the interior base material via a hot-melt film.

[0073] As a vehicle interior material, there is no particular limitation as long as it includes an interior base material and a fibrous carbon sheet laminated on the surface of the interior base material via a hot melt film. The fibrous carbon sheet may be laminated directly on the surface of the interior base material via a hot melt film, or may further include other functional layers having predetermined functions provided on the surface of the interior base material, and the fibrous carbon sheet may be laminated on the surface of the other functional layers via a hot melt film. In addition, the vehicle interior material is usually manufactured by the manufacturing method of the embodiment.

[0074] 2. Method for manufacturing vehicle interior material

[0075] A method for manufacturing a vehicle interior material is a method for manufacturing a vehicle interior material obtained by integrating an interior substrate and a fibrous activated carbon sheet, comprising a lamination step and an integration step. The lamination step is to obtain a laminated body by laminating a fibrous activated carbon sheet on the surface of an interior substrate via a hot melt film, and the hot melt film is provided with at least one of a through hole and a crack. The integration step is to press the laminated body into shape, and integrate the interior substrate and the fibrous activated carbon sheet of the laminated body by welding the hot melt film.

[0076] (1) Lamination process

[0077] The hot melt film between the internal substrate and the fibrous activated carbon sheet in the lamination process is not particularly limited as long as it has at least one of a through hole and a crack. It may be provided with only one of the through hole and the crack as shown in FIG3(a), or it may be provided with both of them as shown in FIG4(a). In addition, a "through hole" refers to a hole or a notch that passes through the hot melt film in the lamination direction. In addition, a "crack" refers to a cut that passes through the hot melt film in the lamination direction and is linear when viewed from the lamination direction.

[0078] Fig. 6 (a) and Fig. 6 (b) are photographs showing another example of the hot melt film of the embodiment. Figure 3(a) and 6(a) As shown in FIG. 6( b ), the through holes may be provided by punching, or as shown in FIG. 6( b ), the through holes may be provided by honeycomb processing. Figure 7(a) to Figure 7(c) This is a photograph of another example of through holes in a hot melt film according to an embodiment. The arrangement of the through holes in the hot melt film is not particularly limited, and examples thereof include a parallel type of circular holes as shown in FIG. 1(b), FIG. 7(a) and FIG. 7(b), a staggered type of circular holes as shown in FIG. 6(a) and FIG. 7(c), and a honeycomb structure as shown in FIG. 6(b). As the shape of the through holes in the hot melt film, for example, circular holes are preferred. This is in view of the ease of processing and equipment limitations during production. As the size of the through holes in the hot melt film when viewed from above, for example, it is preferably within the range of 1 mm or more and 10 mm or less in terms of equivalent circle diameter. Because sufficient air permeability can be obtained by having a size above the lower limit of the range, and by having a size below the upper limit of the range, the situation in which the shape cannot be maintained during punching can be fully suppressed. As the area ratio of the through holes in the hot melt film when viewed from above, for example, it is preferably within the range of 3% or more and 20% or less. When the area ratio of the through holes is above the lower limit of the range, sufficient air permeability can be obtained, and when the area ratio of the through holes is below the upper limit of the range, the situation where the shape cannot be maintained during punching can be sufficiently suppressed.

[0079] The hot melt film is not particularly limited as long as it is a film that melts by heating in the integration process to exhibit adhesion to the internal substrate and the fibrous activated carbon sheet. It can be, for example, a single-layer structure film composed of a fusion layer that melts by heating in the integration process to exhibit adhesion as shown in Figure 4, or it can be, for example, a multi-layer structure film composed of fusion layers that melt by heating in the integration process to exhibit adhesion at least at both ends in the stacking direction as shown in Figure 3.

[0080] As a multi-layered hot-melt film, for example, a heat-resistant layer that does not melt due to heating in the integration process is preferably arranged between the welding layers at both ends of the stacking direction, such as the hot-melt film used in the manufacturing method of the first embodiment. Because in the integration process, when the hot-melt film is welded by pressing the laminated body, only the welding layer can be melted without melting the heat-resistant layer, so the through holes and cracks of the hot-melt film can be kept in the original state, and as a result, the effects of improving the tracking performance and suppressing the formation of wrinkles and uneven welding can be effectively obtained. As such a hot-melt film, for example, a perforated three-layer hot-melt film manufactured by Aichi Plastic Industry Co., Ltd. can be cited.

[0081] The composition of the welding layer is the same as that of the welding layer described in the above-mentioned item “1. Vehicle interior material (1) Hot-melt film”, and thus the description thereof is omitted here. The composition of the heat-resistant layer is the same as that of the heat-resistant layer described in the above-mentioned item “1. Vehicle interior material (1) Hot-melt film”, and thus the description thereof is omitted here.

[0082] The thickness of the hot melt film is not particularly limited. For example, in the case where the hot melt film is a single-layer structure composed of a fusion layer, it is preferably in the range of 30 μm to 100 μm. Because the film thickness is below the lower limit of the range, the film itself can obtain sufficient strength, and the film thickness is below the upper limit of the range, sufficient followability can be obtained. In addition, when the hot melt film is provided with a heat-resistant layer between the fusion layers at both ends of the stacking direction, it is preferred that the thickness of the fusion layer is in the range of 10 μm to 50 μm, and the thickness of the heat-resistant layer is in the range of 10 μm to 50 μm. Because the thickness of the fusion layer is above the lower limit of the range, the film itself can obtain sufficient strength, and the thickness of the fusion layer is below the upper limit of the range, sufficient followability can be obtained. Because the thickness of the heat-resistant layer is above the lower limit of the range, the film itself can obtain sufficient strength and can fully maintain the shape, and the thickness of the heat-resistant layer is below the upper limit of the range, sufficient followability can be obtained.

[0083] The fibrous activated carbon sheet used in the stacking step is the same as the fibrous activated carbon sheet described in the above section “1. Vehicle interior material (2) Fibrous activated carbon sheet”, and therefore the description thereof is omitted here.

[0084] The interior base material used in the lamination step is the same as the interior base material described in the above-mentioned item "1. Vehicle interior material (3) Interior base material", and therefore the description thereof is omitted here.

[0085] (2) Integrated process

[0086] As an integration process, there is no particular limitation as long as it is a process of integrating the inner base material of the stacked body and the fibrous activated carbon sheet by fusing the hot melt film through the stacked body by press molding. For example, as in the first embodiment, there may be a heating process of heating the stacked body and a forming process of press molding the heated stacked body. In addition, as an integration process, it may be a process of press molding the stacked body by a heated forming mold. In such an integration process, the hot melt film can be heated and melted by heating the stacked body with the forming mold during press molding, and then welded to the inner base material and the fibrous activated carbon sheet.

[0087] The heating temperature of the hot melt film is not particularly limited as long as it is a temperature at which the welding layer melts and exhibits adhesive force, and is set according to the composition of the welding layer, etc. For example, it is preferably in the range of 110°C or more and 160°C or less. In addition, when the hot melt film is provided with a heat-resistant layer between the welding layers at both ends of the stacking direction, the heating temperature of the hot melt film is preferably in the range of a temperature above the temperature at which the welding layer melts and exhibits adhesive force, and below the temperature at which the heat-resistant layer melts, for example, it is preferably in the range of 110°C or more and 200°C or less.

[0088] (3) Method for manufacturing vehicle interior material

[0089] The manufacturing method of vehicle interior materials is not particularly limited as long as it includes a stacking step and an integration step. In the stacking step, a stacked body can be obtained by directly stacking fibrous activated carbon sheets on the surface of the interior substrate via a hot melt layer, and the stacked body can be press-formed in the integration step. Alternatively, a stacked body can be obtained by stacking fibrous activated carbon sheets on the surface of other functional layers having predetermined functions provided on the surface of the interior substrate via a hot melt layer in the stacking step, and the stacked body can be press-formed in the integration step.

[0090] Example

[0091] Hereinafter, the vehicle interior material and the method for producing the vehicle interior material of the present invention will be described in more detail with reference to Examples and Reference Examples.

[0092] [Example]

[0093] A storage tray was produced as the vehicle interior material of the present invention.

[0094] First, the interior substrate, the fibrous activated carbon sheet, and the following members as the hot-melt film are prepared (preparation step).

[0095] (Interior base material)

[0096] Product: Interior base material for storage trays manufactured by TAKEHIRO Co., Ltd.

[0097] Composition: Base material composed of polyamide and polyethylene

[0098] Thickness: 5000μm

[0099] (Fiber-like activated carbon sheets)

[0100] Product name: UNITIKA Corporation fiber activated carbon sheet FMS-AC112T6

[0101] Thickness: 1080μm

[0102] (Hot melt film)

[0103] Product name: Perforated three-layer hot-melt film manufactured by Aichi Plastic Industry Co., Ltd.

[0104] Shape and size of outer edge: Same as the shape and size of fibrous activated carbon sheet except for the notch

[0105] Thickness: 50μm (heat-resistant layer thickness: 12μm, welding layer thickness: 19μm)

[0106] The shape and arrangement of through holes when viewed from above: round holes arranged in parallel

[0107] Equivalent circle diameter of through hole when viewed from above: 2.5mm

[0108] Area ratio of through holes when viewed from above: 9%

[0109] Next, the fibrous activated carbon sheet is laminated on one side of the interior substrate via a hot-melt film to obtain a laminate (lamination step). At this time, the outer edge of the hot-melt film overlaps the outer edge of the fibrous activated carbon sheet except for the notch portion.

[0110] Next, the stacked body was placed in a heating furnace and then heated in the heating furnace (heating step). At this time, the stacked body was heated by maintaining the surface temperature of the fibrous activated carbon sheets of the stacked body at 120° C. for 20 seconds.

[0111] Next, the heated stack is arranged between the upper mold and the lower mold of the forming mold, and is pressed and formed by the forming mold (forming process). As a result, the internal substrate of the stack is formed into the shape of the mold surface, and the single-side surface of the internal substrate is formed into a shape with concave and convex parts. At the same time, the fibrous activated carbon sheet and the hot melt film are compressed between the upper mold of the forming mold and the internal substrate, and deformed into the shape of the concave and convex parts along the single-side surface of the internal substrate. Then, the fusion layers at both ends of the stacking direction of the hot melt film are respectively fused to the concave and convex parts of the single-side surface of the internal substrate and the surface of the fibrous activated carbon sheet. In this way, the internal substrate and the fibrous activated carbon sheet of the stack are integrated by the fusion of the hot melt film (integration process).

[0112] Next, the integrated stack is placed between the upper and lower dies of a punching die and cut by the punching die so that the outer edge when viewed from the stacking direction becomes a desired shape (cutting step). Thus, a storage tray (vehicle interior material) is manufactured.

[0113] [Appearance observation]

[0114] FIG8(a) is a photograph of the appearance of the fibrous activated carbon sheet side of the tray manufactured in the embodiment. As shown in FIG8(a), in the tray manufactured in the embodiment, wrinkles and uneven welding of the fibrous activated carbon sheet cannot be confirmed from the appearance. It is believed that the formation of wrinkles and uneven welding of the hot melt film can be suppressed. Furthermore, in FIG8(a), the inner base material is visible behind the tray.

[0115] [Sensory test of deodorizing performance]

[0116] The deodorizing performance of the tray manufactured in the embodiment was evaluated by sensory tests. Specifically, the odor intensity and the discomfort of the odor of the tray manufactured in the embodiment were evaluated by multiple testers according to the following criteria. In addition, the odor intensity of the unique odor of the tray (solvent odor, amine odor, bitterness, sourness, irritation and fishy smell) was also evaluated by multiple testers according to the following criteria. In addition, as a comparison object, the interior substrate used in the embodiment was also evaluated in the same way. Then, for the odor intensity and discomfort of the tray of the embodiment (with activated carbon) and the interior substrate of the comparison object (without activated carbon), as well as the odor intensity of the unique odor, the average value of the evaluation results of all testers was obtained.

[0117] (Odor intensity)

[0118] 4.0: Strong odor

[0119] 3.0: Smell that can be easily detected

[0120] 2.0: Faint smell

[0121] 1.0: A vague smell

[0122] 0.0: Odorless

[0123] (Discomfort)

[0124] 0.0: No discomfort

[0125] -1.0: Slightly uncomfortable

[0126] -2.0: Discomfort

[0127] -3.0: Very uncomfortable

[0128] (Smell intensity of unique odor)

[0129] 4.0: Strong odor

[0130] 3.0: Smell that can be easily detected

[0131] 2.0: Faint smell

[0132] 1.0: A vague smell

[0133] 0.0: Odorless

[0134] Fig. 8(b) is a graph showing the average values ​​of the evaluation results of the odor intensity, discomfort, and odor intensity of the unique odor of the storage tray of the embodiment (with activated carbon) and the interior substrate of the comparative object (without activated carbon). As shown in Fig. 8(b), the average values ​​of the evaluation results of the odor intensity, discomfort, and odor intensity of the unique odor of the embodiment (with activated carbon) are lower than those of the comparative object (without activated carbon).

[0135] [Reference example]

[0136] As a reference example of a vehicle interior material, a floor covering (hereinafter sometimes referred to as an activated carbon integrated floor covering) was prepared, which included an interior base material and a fibrous carbon sheet laminated on the surface of the interior base material via a hot-melt film, and the interior base material and the fibrous carbon sheet were integrated by welding the hot-melt film. Then, a sensory test of deodorization performance and a sensory test of VOC removal performance were conducted on the activated carbon integrated floor covering of the reference example.

[0137] [Sensory test of deodorizing performance]

[0138] The deodorizing performance of the activated carbon integrated floor covering of the reference example was evaluated by a sensory test. Specifically, the odor intensity of the unique odor (solvent odor, amine odor, and acid odor) of the activated carbon integrated floor covering of the reference example was evaluated by multiple testers according to the following standards. In addition, as a comparison object, a conventional floor covering composed of the internal base material used in the activated carbon integrated floor covering of the reference example and without an activated carbon sheet was also evaluated in the same manner. Then, the average value of the evaluation results of all testers was calculated for the odor intensity of the unique odor of the activated carbon integrated floor covering of the reference example and the conventional floor covering of the comparison object.

[0139] (Smell intensity of unique odor)

[0140] 4.0: Strong odor

[0141] 3.0: Smell that can be easily detected

[0142] 2.0: Faint smell

[0143] 1.0: A vague smell

[0144] 0.0: Odorless

[0145] Fig. 9(a) is a graph showing the average values ​​of the evaluation results of the odor intensity of the unique odor of the activated carbon integrated floor covering of the reference example and the conventional floor covering of the comparison object. As shown in Fig. 9(a), the average values ​​of the evaluation results of the odor intensity of the unique odor of the activated carbon integrated floor covering of the reference example are all much lower than those of the conventional floor covering of the comparison object.

[0146] [Sensory test of VOC removal performance]

[0147] The VOC removal performance of the activated carbon integrated floor covering of the reference example was evaluated. Specifically, a plurality of test pieces prepared by cutting the activated carbon integrated floor covering in the stacking direction were placed in an air bag with a volume of 300 liters together with 250 liters of pure air, and heated at 65°C for 2 hours. Then, according to the JASO-M902 method, aldehydes were collected in a DNPH filter cartridge, and other hydrocarbons were collected in a Tenax tube, and then the VOC amount [μg / piece] of each test piece in the air bag was measured using a high-speed liquid chromatograph and a gas chromatograph-mass spectrometer. In addition, as a comparison object, the VOC removal performance of a conventional floor covering composed of the internal substrate used in the reference example and without an activated carbon sheet was also evaluated in the same manner.

[0148] Fig. 9(b) is a graph showing the amount of aldehydes per test piece in the air bag measured for the reference example integrated activated carbon floor covering and the comparative example conventional floor covering. Fig. 9(c) is a graph showing the amount of other hydrocarbons per test piece in the air bag measured for the reference example integrated activated carbon floor covering and the comparative example conventional floor covering.

[0149] As shown in FIG9(b), the VOC amount of aldehydes in each test piece in the airbag measured for the reference example activated carbon integrated floor covering is much lower than that of the conventional floor covering of the comparison object. In addition, as shown in FIG9(c), the VOC amount of other hydrocarbons in each test piece in the airbag measured for the reference example activated carbon integrated floor covering is also much lower than that of the conventional floor covering of the comparison object.

[0150] Although the embodiments of the vehicle interior material and the method for manufacturing the vehicle interior material of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made within the scope described in the claims.

Claims

1. A vehicle interior material, characterized in that: The invention comprises an internal base material and a fibrous activated carbon sheet laminated on the surface of the internal base material via a hot-melt film. The hot melt film is a multilayer structure film in which an inner welding layer, a heat-resistant layer and an outer welding layer are sequentially stacked. The hot melt film is provided with through holes and cracks. The interior base material and the fibrous activated carbon sheet are integrated by welding the hot-melt film. The cracks arranged on the inner side of the hot melt film are cross-shaped, and the through holes are arranged in any one of a circular hole parallel type, a circular hole staggered type, and a honeycomb structure type. The through hole has an equivalent circle diameter in a range of 1 mm or more and 10 mm or less when viewed from above. The area ratio of the through holes of the hot melt film when viewed from above is within a range of 3% to 20%. The thickness of the inner welding layer and the outer welding layer are respectively within a range of 10 μm to 50 μm, and the thickness of the heat-resistant layer is within a range of 10 μm to 50 μm.

2. A method for manufacturing a vehicle interior material according to claim 1, characterized in that: The manufacturing method is a method for manufacturing a vehicle interior material obtained by integrating an interior substrate and a fibrous activated carbon sheet, and comprises a lamination step and an integration step. The lamination step is to obtain a laminated body by laminating the fibrous activated carbon sheet on the surface of the interior substrate via a hot-melt film, wherein the hot-melt film is provided with through holes and cracks. The integration step press-forms the stacked body and integrates the interior base material and the fibrous activated carbon sheet of the stacked body by welding the hot-melt film.

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