Door trim and method for manufacturing the same

Abstract

To provide a door trim in which a base material and a skin are firmly joined via a non-reactive hot melt adhesive layer while suppressing dependence on a material forming a joining surface, and a method for manufacturing the same.SOLUTION: A door trim 1 includes a base material 2 and a skin 3 bonded to a surface of the base material 2. A joint surface S of the base material 2 with the skin 3 has a region S1 formed of polyolefin and / or a region S2 formed of polyurethane. A joint surface T of the skin 3 to the base material 2 is formed by polyolefin, and the joint surface S and the joint surface T are bonded via a non-reactive hot melt adhesive layer, the non-reactive hot melt adhesive layer containing acid-modified polyolefin. A step of joining the joint surface S and the joint surface T by using a non-reactive hot melt adhesive containing the acid-modified polyolefin is provided.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a door trim and a method for manufacturing the same. More specifically, the present invention relates to a door trim including a base material and a skin joined to the surface of the base material, and a method for manufacturing the same.

Background Art

[0002] A door trim, which is an interior material for a vehicle, is mainly composed of a base material and a skin joined to the surface of the base material via an adhesive. This door trim is, for example, exposed to sunlight through a window. That is, the upper part of the trim is subjected to repeated heat ray irradiation, accompanying temperature rise, ultraviolet irradiation, etc. Therefore, high bonding property is required so that the base material and the skin are not peeled off in such an environment.

[0003] Conventionally, a solvent-based adhesive typified by a chloroprene-based adhesive has been used to meet the bonding requirements in such an environment. Although the solvent-based adhesive exhibits excellent bonding property, in recent years, due to the increasing requirements for environmental compatibility, a switch to a solvent-free adhesive is desired. From such a point, an alternative to a reactive hot-melt adhesive, which is an adhesive not using a solvent, is considered. The reactive hot-melt adhesive has an advantage that excellent bonding property and heat resistance can be simultaneously exhibited by polymerization or crosslinking of a base resin. However, the reactive hot-melt adhesive has a problem that it takes time for curing. That is, when used as an adhesive, it takes time for the reaction to proceed. However, if an attempt is made to shorten this reaction time, problems such as deterioration of workability during application of the reactive hot-melt adhesive and stability during storage occur. On the other hand, if an attempt is made to improve the application workability and storage stability, the curing property has to be deteriorated. That is, there is a problem that the problem of shortening the curing time and the problems of improving the application workability and storage stability are in conflict with each other, and it is difficult to achieve both of them. Regarding such problems, Patent Document 1 below is known.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-117606 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Patent Document 1 discloses an interior vehicle material comprising a polyolefin substrate coated with a hot-melt composition comprising (A) amorphous poly-αolefin, (B) crystalline propylene polymer, (C) tackifying resin, and (D) Fischer-Tropsch wax, wherein the content of (D) Fischer-Tropsch wax is 1 to 15 parts by weight per 100 parts by weight of the total weight of (A) to (D). This technology utilizes a hot-melt adhesive, which is a solvent-free adhesive. It is excellent in the purpose of providing a hot-melt adhesive that can be used for lamination of interior vehicle materials, has excellent adhesion and heat resistance, and does not easily transfer to the surface layer of the substrate even when the substrate is stacked and stored after pre-coating it with a surface material or the like. However, in the ever-evolving industrial field, there is a growing demand for better products, and even higher performance and greater flexibility are required.

[0006] This invention has been made in view of the above circumstances, and aims to provide a door trim in which a base material and a surface are firmly joined via a non-reactive hot-melt adhesive layer, while suppressing dependence on the material forming the joining surface, and a method for manufacturing the same. [Means for solving the problem]

[0007] In other words, the present invention includes the following: [1] A door trim comprising a base material and a surface material bonded to the surface of the base material, The bonding surface S of the substrate with the surface has a region S1 without polar groups and / or a region S2 with polar groups. The bonding surface T and the bonding surface S in the surface layer are bonded together via a non-reactive hot-melt adhesive layer. The door trim is characterized in that the non-reactive hot-melt adhesive layer contains an acid-modified polyolefin. [2] The joining surface S is the door trim according to [1] above, comprising the region S1 and the region S2. [3] The region S1 is the door trim according to [1] or [2] above, made of polyolefin. [4] The door trim according to any one of [1] to [3] above, wherein the region S2 is formed using polyurethane. [5] The door trim according to any one of [1] to [4] above, wherein the joint surface T is formed using polyolefin. [6] The door trim according to any one of [1] to [5] above, wherein the joining surface T is the surface of a fiber aggregate. [7] The door trim according to any one of [1] to [6] above, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene. [8] The door trim according to [7] above, wherein the maleic anhydride-modified polypropylene is more than 5% by mass and less than 20% by mass when the entire non-reactive hot melt adhesive layer is considered to be 100% by mass. [9] The door trim according to [7] or [4] above, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

[10] The door trim according to any one of [7] to [9] above, wherein the melt flow rate of the maleic anhydride-modified polypropylene at 180°C is 20 g / 10 min or more.

[11] The door trim according to [1] above, wherein the joining surface S is the region S2.

[12] The door trim according to

[11] above, wherein the region S2 is formed using polyurethane.

[13] The door trim according to

[11] or

[12] above, wherein the joint surface T is formed using polyolefin.

[14] The door trim according to any one of

[11] to

[13] above, wherein the joining surface T is the surface of a fiber aggregate.

[15] The door trim according to any one of

[11] to

[14] above, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

[16] The door trim according to

[15] , wherein the maleic anhydride-modified polypropylene is 5% by mass or more and 40% by mass or less when the entire non-reactive hot melt adhesive layer is considered to be 100% by mass.

[17] The door trim according to

[15] or

[16] above, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

[18] The door trim according to any one of

[15] to

[17] above, wherein the melt flow rate of the maleic anhydride-modified polypropylene at 180°C is 20 g / 10 min or more.

[19] The joining surface S consists of the region S1, The door trim according to [1] above, wherein the non-reactive hot-melt adhesive layer comprises the acid-modified polyolefin and the non-acid-modified polyolefin as a base resin.

[20] The region S1 is the door trim described in

[19] above, which is made of polyolefin.

[21] The door trim according to

[19] or

[20] above, wherein the joint surface T is formed using polyolefin.

[22] The door trim according to any one of

[19] to

[21] above, wherein the joining surface T is the surface of a fiber aggregate.

[23] The door trim according to any one of

[19] to

[22] above, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

[24] The door trim according to

[23] , wherein the maleic anhydride-modified polypropylene is less than 20% by mass when the entire non-reactive hot-melt adhesive layer is considered to be 100% by mass.

[25] The door trim according to

[23] or

[24] above, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

[26] The door trim according to any one of

[23] to

[25] above, wherein the melt flow rate of the maleic anhydride-modified polypropylene at 180°C is 20 g / 10 min or more.

[27] A method for manufacturing a door trim comprising a base material and a surface layer bonded to the surface of the base material, The bonding surface S of the substrate with the surface has a region S1 without polar groups and / or a region S2 having polar groups. A method for manufacturing a door trim, characterized by comprising a bonding step of bonding the bonding surface T and the bonding surface S of the surface with respect to the substrate using a non-reactive hot-melt adhesive containing an acid-modified polyolefin.

[28] The method for manufacturing a door trim according to

[17] above, wherein the joining surface S is comprised of the region S1 and the region S2.

[29] The method for manufacturing a door trim according to

[27] or

[28] above, wherein the region S1 is made of polyolefin.

[30] The method for manufacturing a door trim according to any one of

[27] to

[29] above, wherein the region S2 is formed using polyurethane.

[31] The door trim according to any one of

[27] to

[30] above, wherein the joint surface T is formed using polyolefin.

[32] The method for manufacturing a door trim according to any one of

[27] to

[31] above, wherein the joining surface T is the surface of a fiber aggregate.

[33] A method for manufacturing a door trim according to any one of the above

[27] to

[32] , wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

[34] The method for manufacturing a door trim according to

[33] , wherein the maleic anhydride-modified polypropylene is more than 5% by mass and less than 20% by mass when the entire non-reactive hot melt adhesive layer is considered to be 100% by mass.

[35] A method for manufacturing a door trim according to

[33] or

[34] above, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

[36] The method for manufacturing a door trim according to any one of the above

[33] to

[35] , wherein the melt flow rate of the maleic anhydride-modified polypropylene at 180 °C is 20 g / 10 min or more.

[37] The manufacturing method of the door trim according to

[27] above, wherein the joint surface S consists of the region S2.

[38] The manufacturing method of the door trim according to

[37] above, wherein the region S2 is formed using polyurethane.

[39] The manufacturing method of the door trim according to

[37] or

[38] above, wherein the joint surface T is formed using a polyolefin.

[40] The manufacturing method of the door trim according to any one of

[37] to

[39] above, wherein the joint surface T consists of the surface of a fiber aggregate.

[41] The manufacturing method of the door trim according to

[37] above, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

[42] The manufacturing method of the door trim according to

[41] above, wherein when the entire non-reactive hot melt adhesive layer is 100% by mass, the maleic anhydride-modified polypropylene is 5% to 40% by mass.

[43] The manufacturing method of the door trim according to

[41] or

[42] above, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

[44] The manufacturing method of the door trim according to any one of

[41] to

[43] above, wherein the melt flow rate of the maleic anhydride-modified polypropylene at 180 °C is 20 g / 10 min or more.

[45] The joint surface S consists of the region S1, The manufacturing method of the door trim according to

[27] above, wherein the non-reactive hot melt adhesive contains, as a base resin, the acid-modified polyolefin and a non-acid-modified polyolefin.

[46] The manufacturing method of the door trim according to

[45] above, wherein the region S1 is made of polyolefin.

[47] The manufacturing method of the door trim according to

[45] or

[46] above, wherein the joint surface T is formed using a polyolefin.

[48] The joint surface T is the method for manufacturing the door trim according to any one of the above

[45] to

[47] , which consists of the surface of the fiber aggregate.

[49] The method for manufacturing the door trim according to any one of the above

[45] to

[48] , wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

[50] The method for manufacturing the door trim according to

[45] above, wherein when the entire non-reactive hot-melt adhesive layer is taken as 100% by mass, the maleic anhydride-modified polypropylene is less than 20% by mass.

[51] The method for manufacturing the door trim according to

[49] or

[50] above, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

[52] The method for manufacturing the door trim according to any one of the above

[49] to

[51] , wherein the melt flow rate of the maleic anhydride-modified polypropylene at 180°C is 20 g / 10 minutes or more. [Effect of the Invention]

[0008] According to the door trim of the present invention, it is possible to provide a door trim in which a base material and a skin are firmly joined via a non-reactive hot-melt adhesive layer while suppressing dependence on the material forming the joint surface, and a method for manufacturing the same. According to the method for manufacturing the door trim of the present invention, it is possible to firmly join a base material and a skin via a non-reactive hot-melt adhesive layer while suppressing dependence on the material forming the joint surface. [Brief Description of the Drawings]

[0009] [Figure 1] It is an explanatory diagram for explaining an example of a door equipped with the door trim of the present invention. [Figure 2] It is an explanatory diagram for explaining the disassembled state of the door shown in FIG. 1. [Figure 3] It is an explanatory diagram for explaining the A-A cross section in FIG. 2. [Figure 4] It is an explanatory diagram for explaining the disassembled state of the upper board shown in FIG. 3. [Figure 5] It is an explanatory diagram for explaining the B-B cross section in FIG. 2. [Figure 6] Figure 5 is an explanatory diagram illustrating the disassembled state of the lower board. [Figure 7] This is an explanatory diagram illustrating another example of the AA section shown in Figure 2. [Figure 8] Figure 7 is an explanatory diagram illustrating the disassembled state of the upper board. [Figure 9] Figure 2 shows cross-section AA, which is an explanatory diagram illustrating another example. [Figure 10] Figure 9 is an explanatory diagram illustrating the disassembled state of the upper board. [Figure 11] This graph shows the correlation between peel strength and acid-modified polyolefin content. [Modes for carrying out the invention]

[0010] The present invention will now be described in detail. The matters described herein are illustrative and illustrative to illustrate embodiments of the present invention, and are intended to provide what is considered to be the most effective and straightforward explanation of the principles and conceptual features of the present invention. In this regard, it is not intended to describe structural details of the present invention beyond what is necessary for a fundamental understanding of the invention, but rather to make it clear to those skilled in the art, through the description and drawings, how some forms of the present invention are actually embodied.

[0011] [1] Door trim The door trim (1) of the present invention comprises a base material (2) and a surface layer (3) bonded to the surface of the base material (2). Furthermore, the bonding surface S between the substrate (2) and the skin (3) has a region S1 without polar groups and / or a region S2 with polar groups. Furthermore, the bonding surface T and bonding surface S of the epidermis (3) with the substrate (2) are bonded via a non-reactive hot-melt adhesive layer (4), and the non-reactive hot-melt adhesive layer (4) contains an acid-modified polyolefin.

[0012] The "door trim (1)" described above is a component that covers the door on the interior side of a vehicle door and is responsible for providing various functions such as designing the interior of the vehicle, storage, resting, and shock absorption. This door trim comprises a base material 2 and a surface 3 bonded to its surface, and the surface of the door trim is exposed to the interior side and is given a design. This surface to which the design is given is called the design surface, and in the door trim of the present invention, it is formed by the surface 3.

[0013] The above-mentioned "base material (2)" is a component that makes up the door trim 1 and usually forms the main part of the door trim. The base material 2 has a bonding surface S as a bonding surface with the surface 3. This bonding surface S has a region S1 that does not have polar groups and / or a region S2 that has polar groups. That is, the bonding surface S is <1> It consists of region S1 and region S2, <2> Consists only of region S2, <3> Three types of embodiments are given as examples, consisting only of region S1.

[0014] The "region S" described above refers to the surface of the substrate 2 that is bonded to the epidermis 3. That is, if the entire surface of the substrate 2 is bonded to the epidermis 3, the entire surface of the substrate 2 becomes region S. On the other hand, if only a portion of the surface of the substrate 2 is bonded to the epidermis 3, only a portion of the surface of the substrate 2 becomes region S. Typically, region S occupies 50% or more (it may even be 100%) of the entire surface of the substrate 2.

[0015] The above-mentioned "region S1" is a region that does not contain polar groups. That is, it is formed from a material that does not contain polar groups (hereinafter also simply referred to as "non-polar material"). The non-polar material may be an inorganic material, but it is preferably an organic material, and more preferably a resin. That is, region S1 is preferably formed from a resin that does not contain polar groups (hereinafter also simply referred to as "non-polar resin"). Furthermore, the portion of the base material 2 having region S1 (the portion of the base material 2 where the bonding surface S is region S1) may be made of a non-polar material throughout its entire thickness, or only the surface portion on the bonding surface S side in the thickness direction may be made of a non-polar material, while the other portion may be made of a material having polar groups (hereinafter also simply referred to as "polar material").

[0016] Examples of non-polar resins include polyolefins. These may be used individually or in combination of two or more types. Polar groups include carboxyl groups, acid anhydride groups (such as maleic anhydride, phthalic anhydride, and succinic anhydride), hydroxyl groups, isocyanate groups, amino groups, and halogen groups.

[0017] Among the non-polar resins mentioned above, polyolefins are preferred from the viewpoint of moldability, handling, cost, and versatility. Polyolefins include homopolymers and copolymers of olefins. In the case of olefin copolymers, polyolefin elastomers are included. Olefins are unsaturated hydrocarbons having one carbon-carbon double bond, and include, for example, ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, and 1-octene. These may be used individually or in combination of two or more. In other words, polyolefins include polyethylene, polypropylene, and the like. These polymers may be used individually or in combination of two or more.

[0018] Among the above, polyethylene includes ethylene homopolymers and copolymers of ethylene and other olefins (i.e., ethylene copolymers). The types of other olefins constituting the ethylene copolymer are not limited, and the various olefins mentioned above (except ethylene) can be used. The ethylene copolymer may be a random copolymer or a block copolymer. However, the ethylene copolymer is a polymer in which 50% or more of the total number of constituent units are derived from ethylene. Of the above, polypropylene includes propylene homopolymers and copolymers of propylene with other olefins (i.e., propylene copolymers). The type of other olefin constituting the propylene copolymer is not limited, and the various olefins mentioned above (except propylene) can be used. The propylene copolymer may be a random copolymer or a block copolymer. However, the propylene copolymer is a polymer in which 50% or more of the total number of constituent units are derived from propylene.

[0019] The above-mentioned "region S2" is a region containing polar groups. That is, it is formed from a material containing polar groups (hereinafter also simply referred to as "polar material"). The polar material may be an inorganic material, but it is preferably an organic material, and more preferably a resin. That is, region S2 is preferably formed from a resin containing polar groups (hereinafter also simply referred to as "polar resin"). Furthermore, the portion of the base material 2 having region S2 (the portion of the base material 2 where the bonding surface S is region S2) may be made of a polar material throughout its entire thickness, or only the surface portion on the bonding surface S side in the thickness direction may be made of a polar material, while the other portion is made of a non-polar base material.

[0020] Examples of polar resins include polyurethane, polyethylene terephthalate, polyamide, polycarbonate, acrylic resin, methacrylic resin, polyacrylate, and polymethacrylate. These can be used individually or in combination of two or more. Furthermore, polar groups include carboxyl groups, acid anhydride groups (such as maleic anhydride, phthalic anhydride, and succinic anhydride), hydroxyl groups, isocyanate groups, amino groups, and halogen groups. These may be used individually or in combination of two or more.

[0021] Among the polar resins mentioned above, polyurethane is preferred from the viewpoint of moldability, handling, cost, and versatility. Polyurethane is a polymer containing urethane bonds. Polyurethane may also contain one or more other types of bonds (such as urea bonds) in addition to urethane bonds. Polyurethane can be obtained using polyols and polyisocyanates. Polyols are compounds having two or more hydroxyl groups in their molecule, and include, for example, aliphatic polyols, polyester polyols, polyether polyols, olefin polyols, and acrylic polyols. These may be used individually or in combination of two or more.

[0022] Polyisocyanates are compounds (including monomers, polymers, prepolymers, etc.) having two or more isocyanate groups in their molecule, and include aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates. These may be used individually or in combination of two or more. Among the above, aromatic polyisocyanates include diphenylmethane diisocyanate (monomeric MDI, polymeric MDI, crude MDI), tolylene diisocyanate (TDI), and phenylene diisocyanate. These may be used individually or in combination of two or more. Aliphatic polyisocyanates include hexamethylene diisocyanate and trimethylhexamethylene diisocyanate. These may be used individually or in combination of two or more. Alicyclic polyisocyanates include dicyclohexylmethane diisocyanate, isophorone diisocyanate, and norbornene diisocyanate. These may be used individually or in combination of two or more types.

[0023] As mentioned above, the base material 2 is as follows: <1> ~ <3> Examples of this form are given. <1> The joint surface S consists of region S1 and region S2. <2> The bonding surface S consists only of region S2. <3> The bonding surface S consists only of region S1.

[0024] <1> Form The base material 2 is the above <1> One example of this form is a case in which the material has both a non-polar material portion (e.g., a polyolefin material portion) formed using a non-polar material (e.g., a polyolefin) and a polar material portion (e.g., a polyurethane material portion) formed using a polar material (e.g., a polyurethane) (see Figures 3-6). That is, for example, a base material 2 can be made in which a polar material portion is attached to a part of the surface of the non-polar material portion (the surface that becomes the bonding surface S). In this case, the exposed surface of the non-polar material portion becomes region S1, and the exposed surface of the polar material portion becomes region S2. More specifically, the polyolefin material portion includes <1-1> molded articles made of polyolefin (polyolefin molded articles), and <1-2> fibrous molded articles (excipients for fiber boards) made by using polyolefin as a binder resin and binding multiple plant fibers with the binder resin. On the other hand, examples of polyurethane material parts include (1) molded articles made of polyurethane (polyurethane molded articles) and (2) foamed layers made of polyurethane (urethane pads, etc.).

[0025] <2> Form The base material 2 is the above <2> Examples of such forms include <2-1> a ​​molded body made of a polar material (e.g., polyurethane) (polar material portion (polyurethane material portion)). Also, <2-2> a base material 2 in which a foamed layer made of a polar material (e.g., polyurethane) is bonded to the entire surface of a molded body made of a non-polar material (e.g., polyolefin) (non-polar material portion (polyolefin material portion)) (see Figures 7-8). In these cases, the exposed surface of the polar material portion becomes region S2. Specifically, for example, a base material 2 may be provided in which a layer 22 (e.g., a urethane pad layer 22(22c)) formed of a polar material is bonded to the entire surface of one side of a main body 21(21c) which is a molded body made of a non-polar material, or to one side of a fibrous molded body (an excipient of a fiber board) which is a main body 21(21c). In this base material 2, the entire surface of the bonding surface S becomes the surface of the layer 22(22c) formed of the polar material and corresponds to region S2. Specifically, as illustrated in Figures 7-8, similar to Figures 3-6, the exposed surface of the layer 22(22c) formed of the polar material corresponds to region S2.

[0026] <3> Form The base material 2 is the above <3> Examples of the form include <3-1> a ​​molded body made of a non-polar material (e.g., polyolefin) (non-polar material portion (e.g., polyolefin material portion)) (see Figures 9-10). Another example is <3-2> a base material 2 in which a foamed layer made of a non-polar material (non-polar material portion (e.g., polyolefin material portion)) is attached to the entire surface of a molded body made of a polar material (polar material portion). In these cases, the exposed surface of the non-polar material portion becomes region S1. That is, for example, a polyolefin molded article or a fibrous molded article (an excipient of a fiber board) is used as the base material 2(2d). In this base material 2(2d), since the polyolefin material is present across the entire surface of the bonding surface S, the bonding surface S corresponds to region S1. Specifically, this is illustrated in Figures 9-10.

[0027] Of the above, <1> To describe the form in more detail, in <1-1> above, there is a case in which the entire body is made of a polyolefin molded body and a urethane pad layer made of polyurethane is attached to a part of it, and the base material 2 is made of a polyolefin molded body. In this base material 2, the polyolefin molded body corresponds to the polyolefin material part, and the surface of the polyolefin molded body corresponds to region S1. On the other hand, the urethane pad layer corresponds to the polyurethane material part, and the surface of the urethane pad layer corresponds to region S2.

[0028] Specifically, this is illustrated in Figures 1 to 6. Door 50 refers to the right front door of the vehicle. A similar configuration can be used for the right rear, left front, left rear doors, etc. Door 50 can consist of a door panel 30 and a door trim 1. The door trim 1 is an interior material attached to the interior side of the door panel 30, forming the wall surface of the interior compartment and providing decorative and comfortable features to the interior. Each door panel 30 can be composed of a plate-shaped door outer panel 31 and a door inner panel 32. These panels are obtained by press-forming metal panels such as steel or aluminum. Various components such as window glass (not shown) and a lifting mechanism (not shown) for raising and lowering the window glass can be provided between the door inner panel 32 and the door outer panel 31.

[0029] The door trim 1 can consist of an upper board 11 and a lower board 12. These upper board 11 and lower board 12 are assembled together. Each of these upper board 11 and lower board 12 is made of polyolefin (for example, polypropylene). The upper board 11 may be provided with an inside handle portion 111. The lower board 12 may be provided with an armrest portion 121, a door pull handle portion 122, a speaker grille portion 123, a door pocket portion 124, etc. These are all functional parts; for example, the armrest portion 121 is a part that provides space for an occupant seated in the seat to rest their elbow, and is formed to bulge outwards towards the interior of the cabin.

[0030] Furthermore, a urethane pad layer 22(22a) can be provided on the surface of the armrest portion 121 to provide cushioning for the underside of the elbow when the occupant rests their elbow on it. In this configuration, the lower board 12 comprises a polyolefin body 21(21a) and a urethane pad layer 22(22a) disposed on the surface of the body 21(21a). Therefore, the exposed surface of the polyolefin molded body 21(21a) corresponds to region S1, and the exposed surface of the urethane pad layer 22(22a) corresponds to region S2.

[0031] Similarly, the upper board 11 may be provided with a urethane pad layer 22(22b) on its surface to provide cushioning on the side of the elbow when the occupant rests their elbow on the armrest portion 121. In this configuration, the upper board 11 comprises a polyolefin body 21(21b) and a urethane pad layer 22(22b) disposed on the surface of the body 21(21b). Therefore, the exposed surface of the polyolefin molded body 21(21b) corresponds to region S1, and the exposed surface of the urethane pad layer 22(22b) corresponds to region S2.

[0032] The above <1-2> is a component comprising a main body 21 which is a fibrous molded body (an excipient of a fiber board) made by binding multiple reinforcing fibers using polyolefin as a binder resin, and a pad layer (urethane pad layer) 22 made of polyurethane attached to a part of its surface. In this component, the exposed surface of the fibrous molded body 21 corresponds to region S1, and the exposed surface of the urethane pad layer 22 corresponds to region S2. In this case as well, the same shape and configuration as above can be used.

[0033] Here, there are no limitations on the types of reinforcing fibers mentioned above, and plant fibers, resin fibers (polyester fibers, polyamide fibers, etc.), inorganic fibers (glass fibers, carbon fibers, etc.) can be used. These may be used individually or in combination of two or more. Of the above, plant fibers are fibers extracted from plant bodies (trunks, stems, branches, leaves, roots, etc.) and include vein-type plant fibers, bast-type plant fibers, woody plant fibers, etc. The plant bodies from which the plant fibers are derived are not limited, and examples include kenaf, hemp, jute, ramie, flax, Manila hemp, sisal, ganpi, mitsumata, kozo, banana, pineapple, coconut palm, corn, sugarcane, bagasse, palm, papyrus, reed, esparto, sabaigrass, wheat, rice, bamboo, various coniferous trees (cedar and cypress, etc.), broad-leaved trees, and cotton. These may be used individually or in combination of two or more.

[0034] The ratio of the total amount of reinforcing fibers to the total amount of polyolefin contained in the fiberboard is not limited, but when the sum of the total amount of reinforcing fibers and the total amount of polyolefin is taken as 100% by mass, the ratio of the total amount of reinforcing fibers can be 10 to 90% by mass, preferably 25 to 75% by mass, and more preferably 35 to 65% by mass.

[0035] The "skin (3)" described above is a component that covers the surface of the base material 2. Of the surface of the skin 3, the bonding surface T, which is the surface that is bonded to the base material 2, may be a region without polar groups, a region with polar groups, or a region in which both are present. That is, it may consist only of regions formed from non-polar materials, or only of regions formed from polar materials, or a region in which both are present. As with the case of the base material 2, a non-polar resin (such as polyolefin) is preferred as the non-polar material, and a polar resin (such as polyurethane, polyethylene terephthalate, or polyamide) is preferred as the polar material. Specific examples of non-polar resins and polar resins are also as described above.

[0036] More specifically, as epidermis 3, <4> and <5> Examples of this form are given. <4> The bonding surface T is made of a non-polar material. <5> The bonding surface T is made up of the surface of the fiber aggregate.

[0037] <4> Form The epidermis 3 is as described above <4> One example of this configuration is one in which the bonding surface T is made of a non-polar material, such as polyolefin. The description of polyolefins in the description of base material 2 can be applied directly. Among these, polyolefin elastomers are preferred. More specifically, a surface layer 3, in which a design layer and a foam layer are laminated, is exemplified. Of these layers, the design layer can be formed from various materials, but for example, it can be made of polyolefin or polyvinyl chloride. On the other hand, the foam layer can also be formed from various materials, but for example, it can be made of polyolefin, which is a non-polar resin, and in particular, it can be a foam layer made of polyolefin elastomer. this <4> In this configuration, the surface of the foamed layer made of polyolefin elastomer is considered the bonding surface T. That is, the exposed surface of the foamed layer formed from a non-polar resin is considered the bonding surface T. Furthermore, the design layer is the layer exposed on the interior side and may have color or a pattern. If it has a pattern, it may be a smooth pattern or a textured pattern.

[0038] <5> Form The epidermis 3 is as described above <5> An example of this form is a surface layer 3 in which a design layer, a foam layer, and a fiber aggregate (fiber aggregate layer) are laminated in this order. Of these layers, the design layer is as described above. <4> It can be made similarly to the design layer in the form. Also, the foam layer can be formed from various materials, for example, the above <4> Similar to the form, it can be made of polyolefin, which is a non-polar resin, or it can be made of polyurethane, which is a polar resin (for example, a foamed layer of slab urethane). Furthermore, as the fiber aggregate (fiber aggregate layer), a nonwoven fabric layer, a woven fabric layer, a knitted fabric layer, etc., can be used. These may be used individually or in combination of two or more. The constituent materials of the fibers constituting the fiber aggregate are not limited and may be non-polar materials, polar materials, or even a mixture of these. Examples of fibers constituting the fiber aggregate include polyester fibers such as polyethylene terephthalate fibers, polyamide fibers such as nylon 6 fibers, and polyolefin fibers such as polypropylene fibers. These may be used individually or in combination of two or more. this <5> In this configuration, the surface of the fiber aggregate is considered the bonding surface T. However, since the gaps between the fibers in the fiber aggregate penetrate from front to back, the bonding surface T can provide an anchoring effect to the non-reactive hot-melt adhesive layer 4, regardless of its constituent materials. Furthermore, the design layer is the layer exposed on the interior side and may have color or a pattern. If it has a pattern, it may be a smooth pattern or a textured pattern.

[0039] The above-mentioned "non-reactive hot-melt adhesive layer (4)" (adhesive layer 4) is a layer interposed between the joining surface S and the joining surface T, and is used to join the joining surface S and the joining surface T. This layer is formed from a non-reactive hot-melt adhesive (hereinafter also simply referred to as "adhesive"). The adhesive layer 4 contains an acid-modified polyolefin. In the door trim 1 of the present invention, the inclusion of an acid-modified polyolefin in the adhesive layer 4 strengthens the bond between the joining surface S and the joining surface T. In particular, compared to the case where the adhesive layer 4 does not contain an acid-modified polyolefin, the bond between region S2 (region formed using polyurethane) and the joining surface T (joint surface of the surface 3, for example, when the fibers constituting the fiber aggregate are made of polar resin) can be strengthened.

[0040] The adhesive is a non-reactive hot-melt adhesive. Hot-melt adhesives can be obtained by comprising, for example, a base resin, a tackifier, and a plasticizer. Hot-melt adhesives can be reactive if at least one of these components (for example, the base resin) has reactive groups and can bond with each other (e.g., through curing or crosslinking). Such adhesives are called reactive hot-melt adhesives. When used as an adhesive, reactive hot-melt adhesives can form a strong adhesive layer due to the reaction of the reactive groups. In particular, they can form an adhesive layer with excellent adhesion and heat resistance. On the other hand, reactive hot-melt adhesives have a limited period during which they can be maintained in an unreacted state. Therefore, even if unused, adhesives that have exceeded a predetermined period such as storage period or pot life must be discarded, which leads to increased costs including management and disposal. In contrast, non-reactive hot-melt adhesives are adhesives that do not exhibit the reactivity described above. That is, they are hot-melt adhesives in which none of the components have reactive groups. Because non-reactive hot-melt adhesives do not exhibit the reactivity described above, there is a problem in that it is difficult to obtain sufficient heat resistance. In this regard, the adhesive layer 4 of the present invention contains an acid-modified polyolefin. As a result, even with an adhesive-based adhesive layer 4, excellent bonding strength can be obtained. In addition, excellent heat resistance can be obtained.

[0041] The "acid-modified polyolefin" described above is a polyolefin having an acid-modifying group. Examples of acid-modifying groups include carboxyl groups (-COOH) and acid anhydride groups (-CO-O-OC-). These may be used individually or in combination of two or more. Acid-modified groups can be introduced by methods such as (1) copolymerization using monomers having acid-modified groups, (2) grafting a compound (monomer, polymer, etc.) having acid-modified groups onto the polymer, or (3) oxidative decomposition of the polymer. These methods may be used individually or in combination of two or more, but (1) and / or (2) are preferred.

[0042] Examples of monomers that can be modified with an acid-modified group include monomers having a polymerizable unsaturated bond and an acid anhydride group, and monomers having a polymerizable unsaturated bond and a carboxyl group. Specifically, examples include acid anhydrides such as maleic anhydride, itaconic anhydride, succinic anhydride, glutaric anhydride, adipic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, and butenyl succinic anhydride, and carboxylic acids such as maleic acid, itaconic acid, fumaric acid, acrylic acid, and methacrylic acid. These may be used individually or in combination of two or more. Among these compounds, acid anhydrides are preferred, maleic anhydride and itaconic anhydride are more preferred, and maleic anhydride is particularly preferred.

[0043] On the other hand, the description of polyolefins described in the explanation of region S1 can be directly applied to the polyolefin constituting the backbone of the acid-modified polyolefin. Among these descriptions, polypropylene is preferred. As mentioned above, polypropylene includes propylene homopolymers and copolymers of propylene and other olefins (i.e., propylene copolymers, provided that propylene-derived units account for 50% or more of the total constituent units). The types of other olefins constituting the propylene copolymer are not limited, but olefins having 4 to 8 carbon atoms are preferred, and include 1-butene, 3-methyl-1-butene, 1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, etc. These may be used individually or in combination of two or more.

[0044] Specifically, as the acid-modified polyolefin, maleic anhydride-modified polyolefin and acid-modified polypropylene are preferred, and maleic anhydride-modified polypropylene is even more preferred.

[0045] Furthermore, while the properties of the acid-modified polyolefin are not limited, it is preferable that the acid value (mgKOH / g) of the acid-modified polyolefin be 5 or higher. By having an acid value of 5 or higher, the bonding strength and heat resistance of the resulting adhesive layer 4 can be improved. This acid value is even more preferably 7 or higher, and even more preferably 9 or higher. While there is no upper limit to this acid value, from the viewpoint of ease of handling, it is preferably 20 or less, more preferably 17 or less, and even more preferably 14 or less. These upper and lower limits can be arbitrarily combined. For example, it can be 5 to 20, further 7 to 17, and further 9 to 14. Note that this acid value (mgKOH / g) shall be the value measured in accordance with JIS K2501.

[0046] The MFR (180°C / 2.12N) of the acid-modified polyolefin is preferably 20 g / 10 min or higher. An MFR of 20 g / 10 min or higher improves the bonding strength and heat resistance of the resulting adhesive layer 4. This MFR is more preferably 30 g / 10 min or higher, and even more preferably 40 g / 10 min or higher. While there is no upper limit to this MFR, from the viewpoint of ease of handling, it is preferably 70 g / 10 min or lower, and more preferably 55 g / 10 min or lower. These upper and lower limits can be combined arbitrarily. For example, it can be 20-70 g / 10 min, further 30-55 g / 10 min, and further 40-55 g / 10 min. This MFR (180°C / 2.12N) should be measured according to ISO 1133.

[0047] The melting point of the acid-modified polyolefin is preferably 120°C or higher. A melting point of 120°C or higher improves the bonding strength and heat resistance of the resulting adhesive layer 4. A melting point of 135°C or higher is more preferable, and 145°C or higher is even more preferable. While there is no upper limit to this melting point, from the viewpoint of ease of handling, it is preferably 170°C or lower, and more preferably 160°C or lower. These upper and lower limits can be combined arbitrarily. For example, it can be 120-170°C, further 135-160°C, and further 145-160°C. This melting point should be measured in accordance with JIS K7121.

[0048] The amount of acid-modified polyolefin contained in the adhesive layer 4 is not limited, but it is preferably 5% by mass or more when the entire adhesive layer 4 is considered as 100% by mass. By having an acid-modified polyolefin content of 5% by mass or more, the bonding strength and heat resistance of the resulting adhesive layer 4 can be improved. On the other hand, although there is no upper limit to this content, it is preferably 30% by mass or less from the viewpoint of ease of handling, etc.

[0049] Furthermore, as mentioned above, the base material 2 is: <1> The bonding surface S is a substrate consisting of region S1 and region S2. <2> The bonding surface S is a substrate consisting only of region S2. <3> Examples of substrates in which the bonding surface S consists only of region S1 are shown. Of these, <1> From the viewpoint of bonding strength, the content of acid-modified polyolefin in the adhesive layer 4 used in this form is preferably more than 5% by mass, more preferably 7% by mass or more, even more preferably 9% by mass or more, and particularly preferably 12% by mass or more. On the other hand, there is no upper limit to this content, but from the viewpoint of bonding strength, it is preferably less than 20% by mass, more preferably 19% by mass or less, even more preferably 18% by mass or less, and particularly preferably 17% by mass or less. These upper and lower limits can be combined arbitrarily. For example, it can be more than 5% by mass and less than 20% by mass, 7% by mass or more and 19% by mass or less, 9% by mass or more and 18% by mass or less, and 12% by mass or more and 17% by mass or less.

[0050] Also, among the above, <2> From the viewpoint of bonding strength, the content of acid-modified polyolefin in the adhesive layer 4 used in this form is preferably 5% by mass or more, more preferably 7% by mass or more, even more preferably 9% by mass or more, and particularly preferably 12% by mass or more. On the other hand, there is no upper limit to this content, but from the viewpoint of bonding strength, it is preferably 40% by mass or less, more preferably 35% by mass or less, even more preferably 30% by mass or less, and particularly preferably 25% by mass or less. These upper and lower limits can be combined arbitrarily. For example, it can be 5% by mass or more and 40% by mass or less, 7% by mass or more and 35% by mass or less, 9% by mass or more and 30% by mass or less, and 12% by mass or more and 25% by mass or less.

[0051] Furthermore, of the above, <3> In the form used, the content of acid-modified polyolefin in the adhesive layer 4 is preferably less than 20% by mass, more preferably 19% by mass or less, even more preferably 18% by mass or less, and particularly preferably 17% by mass or less, from the viewpoint of bonding strength. On the other hand, the lower limit of this content is not limited, but it can exceed 0% by mass, be 1% by mass or more, be 2% by mass or more, and be 3% by mass or more. These upper and lower limits can be arbitrarily combined. For example, it can be greater than 0% by mass and less than 20% by mass, 1% by mass or more and 19% by mass or less, 2% by mass or more and 18% by mass or less, and 3% by mass or more and 17% by mass or less.

[0052] As mentioned above, the adhesive may include, for example, a base resin, a tackifier, and a plasticizer. The acid-modified polyolefin mentioned above is included as part of the base resin. The components of the base resin, tackifier, and plasticizer are not limited, but for example, a non-acid-modified polyolefin can be used as the base resin. A non-acid-modified polyolefin is a resin obtained by removing the acid-modified polyolefin from a polyolefin. The description of polyolefins in the explanation of area S1 can be applied directly to non-acid-modified polyolefins.

[0053] Among these, the non-acid-modified polyolefin is preferably a copolymerized polyolefin using two or more different α-olefin monomers. Furthermore, at least one of ethylene, propylene, 1-butene, and 1-octene is preferred as the monomer. More specifically, terpolymers using three monomers (ethylene, propylene, and 1-butene), binary copolymers using two monomers (ethylene and propylene), binary copolymers using two monomers (ethylene and 1-butene), and binary copolymers using two monomers (propylene and 1-butene) are preferred.

[0054] Furthermore, the non-acid-modified polyolefin preferably contains two or more non-acid-modified polyolefins with different melting points, and is particularly preferably a non-acid-modified polyolefin (A) and a non-acid-modified polyolefin (B) having a lower melting point than non-acid-modified polyolefin (A). In this case, the melting point of non-acid-modified polyolefin (A) is preferably 100°C or higher, and the melting point of non-acid-modified polyolefin (B) is preferably less than 100°C. The difference in melting points of the two resins is not limited, but is preferably 10°C or higher, more preferably 20°C or higher, and even more preferably 40°C or higher. On the other hand, the upper limit of this melting point difference is not limited, but from the viewpoint of bonding strength, it is preferably 90°C or lower, more preferably 80°C or lower, and even more preferably 70°C or lower. These upper and lower limits can be arbitrarily combined. For example, it can be 10°C or higher and 90% by mass or lower, 20°C or higher and 80% by mass or lower, and 40°C or higher and 70% by mass or lower. Furthermore, the melting point of non-acid-modified polyolefins shall be defined as the peak temperature of the melting peak obtained by differential scanning calorimetry.

[0055] Examples of tackifiers include petroleum resins, hydrogenated petroleum resins, rosin resins, rosin ester resins, hydrogenated rosin resins, terpene resins, terpene phenol resins, aromatically modified terpene resins, hydrogenated terpene resins, coumarone-indene resins, alkylphenol resins, and xylene resins. These may be used individually or in combination of two or more. Furthermore, examples of waxes include animal waxes, plant waxes, carnauba wax, candelilla wax, wood wax, beeswax, mineral wax, petroleum wax, paraffin wax, microcrystalline wax, petrolatum, higher fatty acid waxes, higher fatty acid ester waxes, and Fischer-Tropsch wax. These may be used individually or in combination of two or more.

[0056] As previously described, the base material 2 is: <1> ~ <3> Examples of the form are given. <1> The joint surface S consists of region S1 and region S2. <2> The bonding surface S consists only of region S2. <3> The bonding surface S consists only of region S1. As for the epidermis 3, <4> ~ <5> Examples of this form are given. <4> The bonding surface T is made of a non-polar material. <5> The bonding surface T is made up of the surface of the fiber aggregate. Therefore, when the joining surface S and the joining surface T are joined via the adhesive layer 4, door trim 1 is obtained for each combination of the above-mentioned joining surfaces S and T.

[0057] Base material <1> × Epidermis <4> Form Specifically, as door trim 1, base material 2 is <1> And the epidermis 3 is <4> One example is a door trim 1 in which a joint surface S, comprising a region S1 formed of polyolefin and a region S2 formed of polyurethane, is joined to a joint surface T formed of polyolefin via an adhesive layer 4. Conventionally, solvent-type adhesives such as chloroprene-based adhesives and reactive hot-melt adhesives have been used in such door trims 1, but these have the problems described above. In this regard, the door trim 1 of the present invention has an adhesive layer 4 made of a non-reactive hot-melt adhesive. Therefore, it does not cause the problem of solvent release and can simultaneously solve the problems of shortening curing time and improving application workability and storage stability. This is achieved by including an acid-modified polyolefin in the non-reactive hot-melt adhesive that makes up the adhesive layer 4. That is, by including an acid-modified polyolefin in the adhesive layer 4, excellent bonding between the joint surface S and the joint surface T as described above can be achieved.

[0058] Base material <1> × Epidermis <5> Form Furthermore, as door trim 1, base material 2 is <1> And the epidermis 3 is <5> One example is a door trim 1 in which a bonding surface S comprising a region S1 formed of polyolefin and a region S2 formed of polyurethane is bonded to a bonding surface T consisting of the surface of a fiber aggregate via an adhesive layer 4. In such a door trim 1, the base material 2 is <1> And the epidermis 3 is <4> Similar to the case described above, the adhesive layer 4, by containing acid-modified polyolefin, can achieve excellent bonding between the bonding surface S and the bonding surface T, and at the bonding surface T, a strong bond can be achieved by utilizing the anchoring effect on the surface of the fiber aggregate. In particular, this bond can be achieved regardless of the material of the fibers constituting the fiber aggregate. Furthermore, as mentioned above, even in the case of the surface layer 3 in which the design layer, the slab urethane layer, and the fiber aggregate layer are laminated in this order, the adhesive that penetrates into the fiber aggregate layer is superior in that it can also ensure bonding with the slab urethane layer.

[0059] Base material <2> × Epidermis <4> Form Furthermore, as door trim 1, base material 2 is <2> And the epidermis 3 is <4> One example is a door trim 1 in which a bonding surface S consisting of a region S2 formed of polyurethane and a bonding surface T formed of polyolefin are bonded via an adhesive layer 4. In such a door trim 1, the base material <1> × Epidermis <4> Similar to the above configuration, since the adhesive layer 4 is made of a non-reactive hot-melt adhesive containing acid-modified polyolefin, it does not cause solvent release problems, and simultaneously solves the problems of shortening curing time, improving application workability and storage stability, while also achieving excellent bonding between the joint surface S and the joint surface T.

[0060] Base material <2> × Epidermis <5> Form Furthermore, as door trim 1, base material 2 is <2> And the epidermis 3 is <5> One example is a door trim 1 in which a bonding surface S consisting of a region S2 formed of polyurethane and a bonding surface T consisting of the surface of a fiber aggregate are bonded via an adhesive layer 4. In such a door trim 1, the base material <1> × Epidermis <5> Similar to the configuration, the adhesive layer 4, by containing acid-modified polyolefin, achieves excellent bonding between the bonding surface S and the bonding surface T. Furthermore, at the bonding surface T, a strong bond can be achieved by utilizing the anchoring effect on the surface of the fiber aggregate. Moreover, this bond can be achieved regardless of the material of the fibers constituting the fiber aggregate. In addition, even in the case of a surface layer 3 in which the design layer, slab urethane layer, and fiber aggregate layer are laminated in this order, the adhesive that penetrates into the fiber aggregate layer is superior in that it can also ensure bonding with the slab urethane layer.

[0061] Base material <3> × Epidermis <4> Form Furthermore, as door trim 1, base material 2 is <3> And the epidermis 3 is <4> One example is a door trim 1 in which a bonding surface S consisting of a region S1 formed of polyolefin and a bonding surface T formed of polyolefin are bonded via an adhesive layer 4. In such a door trim 1, since the adhesive layer 4 is made of a non-reactive hot melt adhesive containing acid-modified polyolefin, there is no problem of solvent release, and the issues of shortening curing time, improving application workability and storage stability can be solved at the same time, and excellent bonding between the bonding surface S and the bonding surface T can be achieved. In addition, if the base material 2 is made of polyolefin, which is a non-polar material, and the surface layer 3 is made of polyolefin (thermoplastic polyolefin, etc.), then these base material 2 and surface layer 3 are bonded via the adhesive layer 4, and all layers can be formed of olefin-based materials. That is, the constituent materials can be unified, and the door trim 1 can be made of a single material. Since olefin-based materials have excellent recyclability, the monomaterialization of the door trim 1 can provide excellent recyclability.

[0062] Base material <3> × Epidermis <5> Form Furthermore, as door trim 1, base material 2 is <3> And the epidermis 3 is <5> One example is a door trim 1 in which a bonding surface S consisting of a region S1 formed of polyolefin and a bonding surface T consisting of the surface of a fiber aggregate are bonded via an adhesive layer 4. In such a door trim 1, a strong bond can be achieved by utilizing the anchoring effect on the surface of the fiber aggregate. Furthermore, if the material of the fibers constituting the fiber aggregate is polyolefin, all layers can be formed from olefin-based materials. That is, the constituent materials can be unified, and the door trim 1 can be made from a single material. Since olefin-based materials have excellent recyclability, the monomaterialization of the door trim 1 can provide excellent recyclability.

[0063] [2] Method for manufacturing door trim The present invention relates to a method for manufacturing a door trim, comprising a base material 2 and a surface layer 3 bonded to the surface of the base material 2. The bonding surface S between the substrate 2 and the surface 3 has a region S1 formed of polyolefin and / or a region S2 formed of polyurethane. The bonding surface T between the epidermis 3 and the substrate 2 is formed of polyolefin. The invention further features a bonding step in which bonding surfaces S and T are joined using a non-reactive hot-melt adhesive containing an acid-modified polyolefin.

[0064] In other words, the joining process can be described as the process of forming the adhesive layer 4 as explained in [1] above. Here, the door trim 1, base material 2, surface 3, joining surface S, region S1, region S2, joining surface T, and adhesive are as described above.

[0065] The adhesive is typically applied to either or both of the joining surfaces S and T, then the two joining surfaces are brought into contact, and pressure is applied as necessary to obtain the adhesive layer 4. The method of applying the adhesive is not limited, and conventionally known methods can be used as appropriate. The application method may be a contact application method or a non-contact application method. A contact application method is a method in which the application device and the object to be coated are in contact when applying the adhesive, while a non-contact application method is a method in which the application device and the object to be coated are not in contact when applying the adhesive. Examples of contact application methods include roll coater coating and slot coater coating. Examples of non-contact application methods include spiral coating, omega coating, control seam coating, slot spray coating, curtain spray coating, and dot coating. These may be used individually or in combination of two or more. [Examples]

[0066] The present invention will be specifically described below with reference to examples. We investigated the effect of adhesives with varying concentrations of acid-modified polyolefin on the bonding strength of polyolefin substrates and polyolefin surface coatings. Similarly, we investigated the effect of adhesives with varying concentrations of acid-modified polyolefin on the bonding strength of polyurethane substrates and polyolefin surface coatings.

[0067] [1] Bonding of the substrate and the surface The following (1) to (5) were used. (1) Base material A: Molded body made of polypropylene (2) Base material B: Molded body made of foamed polyurethane (3) Skin: Skin made of polyolefin elastomer (4) Non-reactive hot melt adhesive: Manufactured by Showa Denko Materials, product name "Hybon ZH601-1", non-reactive polyolefin hot melt adhesive (5) Acid-modified polyolefin: Maleic anhydride-modified polypropylene (manufactured by Mitsubishi Chemical, product name "Modic P908", acid value 12.8)

[0068] The above (4) and (5) were mixed using a twin-screw extruder at 200°C so that (5) accounted for 5 to 40% by mass of the total, to obtain an adhesive containing acid-modified polyolefin.

[0069] The adhesives, each containing different amounts of acid-modified polyolefin, were placed in a roll coater-type coating apparatus and applied to the bonding surface of the skin at 180°C to a coating thickness of 80 μm. Next, the skin, heated to 170°C, was placed on the bonding surface of base material A at room temperature (25°C) (at a temperature of 115°C), and then pressure was applied to bond base material A and the skin. In each bonded specimen (test piece) of the obtained substrate A and epidermis, the peel strength required to remove the epidermis from the substrate A was measured at a temperature of 100°C. The results are shown in Table 1 and Figure 11.

[0070] The adhesives with different acid-modified polyolefin content obtained above were each placed in a roll coater type coating apparatus and applied to the bonding surface of the skin at 180°C to a coating thickness of 80 μm. Next, the skin, heated to 170°C, was placed on the bonding surface of base material B, which was at room temperature (25°C) (the temperature at which point was 115°C), and then pressure was applied to bond base material B and the skin. In each bonded specimen (test piece) of the obtained substrate B and epidermis, the peel strength required to remove the epidermis from the substrate B was measured at a temperature of 80°C. The results are shown in Table 1 and Figure 11.

[0071] [Table 1]

[0072] Furthermore, the foregoing description is for illustrative purposes only and should not be interpreted as limiting the present invention. Although the present invention has been described with reference to typical embodiments, the language used in the description of the present invention should be understood as descriptive and illustrative, not restrictive. As detailed herein, modifications are possible within the scope or spirit of the present invention without departing in any way. While specific structures, materials, and embodiments have been referenced in the detailed description of the present invention, the present invention is not intended to be limited to the disclosures herein, but rather to encompass all functionally equivalent structures, methods, and uses within the scope of the appended claims. [Industrial applicability]

[0073] The door trim and its manufacturing method according to the present invention can be used in various technical fields. Specifically, it is suitably used as a door trim and its manufacturing method for various vehicles (automobiles and railway vehicles, aircraft, ships, etc.). [Explanation of symbols]

[0074] 1; Door trim, 2; Base material (main body), 3; epidermis; 4; Non-reactive hot melt adhesive layer, 30; Door panel, 31; Door outer panel, 32; Door inner panel, 50; Door 11; Upper board, 12; Lower board, 21; Main body, 22; Urethane pad layer, 111; Inside handle section, 121; Armrest section, 122; Door pull handle section, 123; Speaker grille section, 124; Door pocket area.

Claims

1. A door trim comprising a base material and a surface layer bonded to the surface of the base material, The bonding surface S with the surface of the substrate is a region S that does not have polar groups. １ , and / or regions S having polar groups ２ , has, The bonding surface T and the bonding surface S in the surface layer are joined via a non-reactive hot-melt adhesive layer. The non-reactive hot-melt adhesive layer comprises an acid-modified polyolefin. A door trim characterized in that the melt flow rate of the acid-modified polyolefin at 180°C is 20 g / 10 min or more.

2. The joining surface S is the region S １ and the area S ２ A door trim according to claim 1, comprising the following components.

3. The aforementioned region S １ The door trim according to claim 2, which is made of polyolefin.

4. The aforementioned region S ２ The door trim according to claim 2, which is formed using polyurethane.

5. The door trim according to claim 2, wherein the joining surface T is formed using polyolefin.

6. The door trim according to claim 2, wherein the joining surface T is the surface of a fiber aggregate.

7. The door trim according to claim 2, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

8. The door trim according to claim 7, wherein, when the entire non-reactive hot-melt adhesive layer is considered to be 100% by mass, the maleic anhydride-modified polypropylene is more than 5% by mass and less than 20% by mass.

9. The door trim according to claim 7, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

10. The joining surface S is the region S ２ A door trim according to claim 1, comprising the following components.

11. The door trim according to claim 10, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

12. The door trim according to claim 11, wherein, when the entire non-reactive hot-melt adhesive layer is considered to be 100% by mass, the maleic anhydride-modified polypropylene is 5% by mass or more and 40% by mass or less.

13. The door trim according to claim 11, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

14. The joining surface S is the region S １ It consists of, The door trim according to claim 1, wherein the non-reactive hot-melt adhesive layer comprises the acid-modified polyolefin and a non-acid-modified polyolefin as a base resin.

15. The door trim according to claim 14, wherein the acid-modified polyolefin is maleic anhydride-modified polypropylene.

16. The door trim according to claim 15, wherein the maleic anhydride-modified polypropylene is less than 20% by mass when the entire non-reactive hot-melt adhesive layer is considered to be 100% by mass.

17. The door trim according to claim 15, wherein the acid value of the maleic anhydride-modified polypropylene is 5 to 20.

18. A method for manufacturing a door trim comprising a base material and a surface layer bonded to the surface of the base material, The joint surface S between the skin of the base material has a region S without polar groups １ , and / or a region S with polar groups ２ , and has The bonding step includes joining the bonding surface T and bonding surface S of the surface with respect to the substrate using a non-reactive hot-melt adhesive containing an acid-modified polyolefin. A method for manufacturing a door trim, characterized in that the melt flow rate of the acid-modified polyolefin at 180°C is 20 g / 10 min or more.

19. The joining surface S is the region S １ and the area S ２ A method for manufacturing a door trim according to claim 18, comprising the above.

20. The joining surface S is the region S ２ A method for manufacturing a door trim according to claim 18, comprising the above.

21. The joining surface S is the region S １ A method for manufacturing a door trim according to claim 18, comprising the above.

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