Laminate for automobile interior and instrument panel

Abstract

To provide a laminate for automobile interior which exhibits enhanced adhesion between an adhesive layer and a thermoplastic elastomer layer, and superior releasability during molding.SOLUTION: A laminate for automobile interior comprises a thermoplastic elastomer layer composed of a thermoplastic elastomer composition and an adhesive layer, the thermoplastic elastomer composition containing the following components (A) to (C): Component (A): a propylene-based polymer. Component (B): an ethylene-α-olefin copolymer. Component (C): a silicone oil.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a laminate for automobile interiors and an instrument panel. [Background technology]

[0002] Generally, automotive interior parts such as instrument panels (dashboards) are composed of laminates, which are made up of a skin layer forming the outermost layer, an adhesive layer, and a thermoplastic elastomer layer as a base material. The adhesive layer is made of polyurethane, polyethylene, or polypropylene, or a foamed version of these. Here, the thermoplastic elastomer layer and the adhesive layer are laminated by subjecting the surface of the thermoplastic elastomer layer to an oxidation treatment.

[0003] The thermoplastic elastomer layer described in Patent Document 1 is used for automobile interiors, and therefore contains a lubricant as an additive to improve fogging resistance so that organic components do not diffuse into the air, and also to improve moldability and releasability from the viewpoint of production efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-28789 Summary of the Invention [Problem to be solved by the invention]

[0005] The present inventors have found through investigation that when an adhesive layer and a conventional thermoplastic elastomer layer are laminated together, there is a problem in that the two layers peel off from each other.

[0006] Therefore, an object of the present invention is to provide a laminate for automobile interiors that has improved adhesion between the adhesive layer and the thermoplastic elastomer layer and also has excellent releasability during molding. [Means for solving the problem]

[0007] In view of these circumstances, the present inventors have conducted extensive research and have surprisingly found that in a laminate for automotive interior use comprising a thermoplastic elastomer layer made of a thermoplastic elastomer composition and an adhesive layer, when the thermoplastic elastomer composition contains a specific component, the adhesion between the adhesive layer and the thermoplastic elastomer layer is improved, resulting in excellent releasability during molding, and have thus completed the present invention.

[0008] That is, the present invention provides the following.

[0009] Aspect 1 of the present invention is The present invention relates to a laminate for automobile interiors, which comprises a thermoplastic elastomer layer made of a thermoplastic elastomer composition and an adhesive layer, wherein the thermoplastic elastomer composition contains the following components (A) to (C): Component (A): Propylene polymer Component (B): Ethylene-α-olefin copolymer Component (C): Silicone oil

[0010] A second aspect of the present invention is the laminate for automobile interior use of the first aspect, The present invention relates to an automotive interior laminate, wherein the adhesive layer comprises at least one of polyurethane, polyethylene, and polypropylene.

[0011] A third aspect of the present invention relates to the laminate for automobile interior use according to the first or second aspect, The present invention relates to an automotive interior laminate, wherein the adhesive layer comprises polyurethane.

[0012] A fourth aspect of the present invention relates to the laminate for automobile interior use according to any one of the first to third aspects, The present invention relates to a laminate for an automotive interior, wherein the adhesive layer comprises a polyurethane foam.

[0013] A fifth aspect of the present invention relates to the laminate for automobile interior use according to any one of the first to fourth aspects, The present invention relates to a laminate for automobile interiors, wherein the component (A) comprises at least one selected from the group consisting of propylene homopolymers and propylene-based block copolymers.

[0014] A sixth aspect of the present invention relates to the laminate for automobile interior use according to any one of the first to fifth aspects, The present invention relates to a laminate for automobile interiors, wherein the component (A) comprises a propylene-based block copolymer.

[0015] A seventh aspect of the present invention relates to the laminate for automobile interior use according to the sixth aspect, The present invention relates to a laminate for automobile interiors, wherein the propylene-based block copolymer comprises a block (a1) having a propylene unit content of 90 to 100% by mass and a block (a2) having a propylene unit content of 30 to 70% by mass and an ethylene unit content of 30 to 70% by mass.

[0016] Aspect 8 of the present invention relates to the laminate for automobile interior use according to any one of aspects 1 to 7, wherein The present invention relates to a laminate for automobile interiors, wherein the α-olefin of component (B) has 3 to 8 carbon atoms.

[0017] A ninth aspect of the present invention is the laminate for automobile interior use according to any one of the first to eighth aspects, wherein The present invention relates to a laminate for automobile interiors, wherein the component (B) comprises at least one selected from the group consisting of ethylene-α-olefin random copolymers and ethylene-α-olefin block copolymers.

[0018] A tenth aspect of the present invention relates to the laminate for automobile interior use according to any one of the first to ninth aspects, The viscosity of the silicone oil of the component (C) (measurement condition: 25°C) is 1 to 10,000 mm 2 The present invention relates to a laminate for automobile interiors, which is / s.

[0019] An eleventh aspect of the present invention relates to the laminate for automobile interior use according to any one of the first to tenth aspects, The present invention relates to a laminate for automobile interiors, wherein the content of the component (C) in the thermoplastic elastomer composition is 0.1 to 0.5 parts by mass per 100 parts by mass of the total amount of the components (A) and (B).

[0020] A twelfth aspect of the present invention is the laminate for automobile interior use according to any one of the first to eleventh aspects, wherein The present invention relates to a laminate for automobile interiors, wherein the melt flow rate of the thermoplastic elastomer composition is 2 to 15 g / 10 min.

[0021] A thirteenth aspect of the present invention relates to the laminate for automobile interior use according to any one of the first to twelfth aspects, The present invention relates to a laminate for an automobile interior, including an outermost layer.

[0022] A fourteenth aspect of the present invention is the laminate for automobile interior use of the thirteenth aspect, The present invention relates to a laminate for automobile interiors, which is composed of the outermost layer, the adhesive layer, and the thermoplastic elastomer layer in this order.

[0023] A fifteenth aspect of the present invention is The present invention relates to an instrument panel comprising the laminate for automobile interior use according to any one of the first to fourteenth embodiments.

[0024] A sixteenth aspect of the present invention provides the instrument panel of the fifteenth aspect, The present invention relates to an instrument panel, wherein the thermoplastic elastomer layer is an airbag housing cover layer. [Effects of the Invention]

[0025] According to the present invention, it is possible to provide a laminate for automobile interior use that has improved adhesion between the adhesive layer and the thermoplastic elastomer layer and also has excellent releasability during molding. DETAILED DESCRIPTION OF THE INVENTION

[0026] The following describes in detail the embodiments of the present invention, but the following embodiments are merely examples of the present invention and the present invention is not limited thereto. The present invention can be carried out in any modified form without departing from the gist of the present invention. In this specification, when "~" is used to express a numerical value or a physical property value, the values ​​before and after the "~" are included.

[0027] <Laminate for automotive interiors> The laminate for automobile interior use according to this embodiment includes a thermoplastic elastomer layer made of a thermoplastic elastomer composition and an adhesive layer, and the thermoplastic elastomer composition contains the following components (A) to (C): Component (A): Propylene polymer Component (B): Ethylene-α-olefin copolymer Component (C): Silicone oil

[0028] [Thermoplastic elastomer layer] The thermoplastic elastomer layer contained in the laminate for automobile interior use according to this embodiment is made of a thermoplastic elastomer composition. The components (A) to (C) contained in the thermoplastic elastomer composition are described in detail below.

[0029] (Component (A)) The thermoplastic elastomer composition according to this embodiment contains a propylene polymer as component (A), which contributes to rigidity, heat resistance, and impact resistance.

[0030] From the viewpoints of rigidity, heat resistance, and impact resistance, component (A) preferably contains at least one selected from the group consisting of propylene homopolymers and propylene-based block copolymers, and more preferably contains a propylene-based block copolymer.

[0031] From the viewpoints of rigidity, heat resistance, and impact resistance, the propylene-based block copolymer preferably contains a block (a1) having a propylene unit content of 90 to 100% by mass and a block (a2) having an ethylene unit content of 30 to 70% by mass, and more preferably contains a block (a1) having a propylene unit content of 90 to 100% by mass and a block (a2) having a propylene unit content of 30 to 70% by mass and an ethylene unit content of 30 to 70% by mass.

[0032] From the viewpoints of rigidity, heat resistance, and impact resistance, when the total of block (a1) and block (a2) is taken as 100% by mass, the content of block (a1) is preferably more than 80% by mass but not more than 100% by mass, more preferably 82 to 95% by mass, and even more preferably 83 to 93% by mass.

[0033] In one embodiment, the propylene unit content of the block (a1) is preferably 90 to 100% by mass, more preferably 93 to 100% by mass, and even more preferably 95 to 100% by mass, based on the total mass of the block (a1). When the propylene unit content of the block (a1) is equal to or greater than the lower limit, the heat resistance and rigidity tend to be good. The propylene unit content of the block (a1) can be determined by infrared spectroscopy. The same applies to the ethylene unit content of the block (a2) described below.

[0034] The block (a1) may be a homopolymer of propylene. When the block (a1) is a homopolymer of propylene, the propylene unit content of the block (a1) is 100% by mass.

[0035] Block (a1) may be a propylene-ethylene copolymer, a propylene-α-olefin copolymer, a propylene-ethylene-α-olefin copolymer, or a propylene-ethylene-α-olefin copolymer containing, in addition to propylene units, ethylene units, α-olefin units other than propylene, monomer units other than ethylene and α-olefins, etc. The content of ethylene units, α-olefin units other than propylene, monomer units other than ethylene and α-olefins, etc. is preferably 0 to 10% by mass, more preferably 0 to 7% by mass, and even more preferably 0 to 5% by mass, based on the total mass of block (a1).

[0036] In component (A), block (a1) contributes to rigidity and heat resistance.

[0037] When block (a1) in component (A) is a propylene-α-olefin copolymer or a propylene-ethylene-α-olefin copolymer, the α-olefin units other than propylene may be, for example, α-olefins having 4 to 20 carbon atoms. Examples of α-olefins having 4 to 20 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-ethyl-1-hexene, and 2,2,4-trimethyl-1-pentene. The α-olefin other than propylene is preferably an α-olefin having 4 to 10 carbon atoms, more preferably 1-butene, 1-hexene, or 1-octene.

[0038] Specific examples of block (a1) include propylene homopolymer, propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, and propylene-ethylene-1-octene copolymer.

[0039] In one embodiment, block (a2) may be an ethylene-propylene copolymer having an ethylene unit content of 30 to 70% by mass, or may be an ethylene-propylene-α-olefin copolymer containing, in addition to propylene units and ethylene units, 10% by mass or less of α-olefin units other than propylene, other monomer units, and the like.

[0040] In component (A), block (a2) contributes to impact resistance and dispersibility with component (B).

[0041] When the block (a2) is an ethylene-propylene-α-olefin copolymer, the α-olefins in the α-olefin units thereof may be those exemplified as the α-olefins in the block (a1), and the same applies to the preferred α-olefins. However, in order to obtain suitable physical properties for block (a2), block (a2) preferably contains 5% by mass or more of propylene units relative to the entire block (a2), and particularly preferably block (a2) contains 30 to 70% by mass of ethylene units and 30 to 70% by mass of propylene units.

[0042] Component (A) may be a propylene-based block copolymer obtained by mixing a propylene-based polymer corresponding to block (a1) with an ethylene-propylene copolymer corresponding to block (a2), or a propylene-based block copolymer obtained by polymerizing a propylene-based polymer corresponding to block (a1) with a propylene-ethylene copolymer corresponding to block (a2). From the viewpoints of low-temperature impact resistance and high-temperature strength, component (A) is more preferably a propylene-based block copolymer obtained by polymerizing a propylene homopolymer corresponding to block (a1) in a first step and subsequently polymerizing a propylene-ethylene copolymer corresponding to block (a2) in a second step.

[0043] From the viewpoint of the appearance of the obtained molded article, the melt flow rate (MFR) of component (A) is preferably 5 g / 10 min or more, more preferably 8 g / 10 min or more, and even more preferably 10 g / 10 min or more. Furthermore, the melt flow rate of component (A) is usually 150 g / 10 min or less, and from the viewpoint of tensile strength, it is preferably 130 g / 10 min or less, more preferably 100 g / 10 min or less. The melt flow rate of component (A) is measured in accordance with ISO 1133 at a measurement temperature of 230°C and a measurement load of 21.18 N.

[0044] The propylene polymer of component (A) can be produced by a known polymerization method using a known olefin polymerization catalyst. For example, a multi-stage polymerization method using a Ziegler-Natta catalyst can be used. The multi-stage polymerization method can be a slurry polymerization method, a solution polymerization method, a bulk polymerization method, a gas phase polymerization method, or the like, or a combination of two or more of these methods.

[0045] Furthermore, a commercially available product can also be used as component (A) of the thermoplastic elastomer composition according to this embodiment. The propylene polymer in component (A) can be procured from the manufacturers listed below and can be appropriately selected. Available commercially available products include Prim Polypro® from Prime Polymer Co., Ltd., Sumitomo Noblen® from Sumitomo Chemical Co., Ltd., polypropylene block copolymer from SunAllomer Co., Ltd., Novatec® PP from Japan Polypropylene Corporation, Moplen® from LyondellBasell, ExxonMobil PP from ExxonMobil, Formolene® from Formosa Plastics, Borealis PP from Borealis, Seetec PP from LG Chemical, ASI POLYPROPYLENE from A. Schulman, INEOS PP from INEOS Olefins & Polymers, Braskem PP from Braskem, Samsung Total from SAMSUNG TOTAL PETROCHEMICALS, Sabic® PP from Sabic, TOTAL PETROCHEMICALS Polypropylene from TOTAL PETROCHEMICALS, and YUPLENE® from SK Corporation.

[0046] The thermoplastic elastomer composition according to this embodiment may contain only one type of component (A), or may contain two or more types that differ in monomer unit composition, physical properties, and the like.

[0047] In the thermoplastic elastomer composition according to this embodiment, the content of component (A) is preferably 40 to 60% by mass, more preferably 43 to 57% by mass, and even more preferably 45 to 55% by mass. A content of component (A) of 40% by mass or more is preferred in order to maintain the rigidity and heat resistance of the base material, and a content of 60% by mass or less is preferred in terms of impact resistance.

[0048] The content of component (A) is preferably 40 to 60 parts by mass, more preferably 43 to 57 parts by mass, and even more preferably 45 to 55 parts by mass, relative to 100 parts by mass of the total amount of components (A) and (B). A content of component (A) of 40 parts by mass or more relative to 100 parts by mass of the total amount of components (A) and (B) is preferred in order to maintain rigidity and heat resistance as a base material, and a content of 60 parts by mass or less is preferred in terms of impact resistance.

[0049] (Component B) The thermoplastic elastomer composition according to this embodiment contains an ethylene-α-olefin copolymer as component (B), which contributes to improving low-temperature impact resistance.

[0050] In this specification, when propylene is contained as the α-olefin of an ethylene-α-olefin copolymer, the content (mass%) of ethylene monomer units and propylene monomer units contained in the copolymer is compared to determine whether the copolymer belongs to component (A) or component (B). That is, when the ethylene monomer units in an ethylene-α-olefin copolymer are more than the propylene monomer units, the copolymer belongs to component (B). On the other hand, when the propylene monomer units in an ethylene-α-olefin copolymer are more than the ethylene monomer units, the copolymer belongs to component (A). In this specification, when the propylene monomer units and ethylene monomer units in an ethylene-α-olefin copolymer are equal in amount, the copolymer belongs to component (B).

[0051] When component (B) is an olefin-based block copolymer containing a polymer block of ethylene and a block of an ethylene-α-olefin copolymer, the polymer block of ethylene is primarily ethylene, but may contain other monomer units in addition to ethylene. Here, "primarily" refers to a ratio of 50% by mass or more, particularly 55 to 80% by mass, of the total. Examples of other monomer units include 1-propylene, 1-butene, 2-methylpropylene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene. Preferred are α-olefins having 3 to 8 carbon atoms and a carbon-carbon double bond at the terminal carbon atom, such as 1-propylene, 1-butene, 1-hexene, and 1-octene. When component (B) contains other monomer units in addition to ethylene, only one of the other monomers may be copolymerized with ethylene, or two or more of the other monomers may be copolymerized with ethylene.

[0052] Examples of the ethylene-α-olefin copolymer of component (B) include those having, in addition to ethylene units, α-olefins such as 1-propylene, 1-butene, 2-methylpropylene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene as structural units. The α-olefin preferably has 3 to 8 carbon atoms, and more preferably α-olefins having 3 to 8 carbon atoms and a carbon-carbon double bond at a terminal carbon atom, such as 1-propylene, 1-butene, 1-hexene, and 1-octene. Specific examples include block copolymers containing a polymer block consisting of ethylene and an ethylene-α-olefin copolymer block, such as an ethylene-1-butene copolymer, an ethylene-1-hexene copolymer, an ethylene-1-octene copolymer, an ethylene-propylene-1-butene copolymer, an ethylene-propylene-1-hexene copolymer, or an ethylene-propylene-1-octene copolymer. Among these, component (B) is most preferably an olefin-based block copolymer containing a polymer block made of ethylene and a block of an ethylene-1-octene copolymer.

[0053] The α-olefin in the ethylene-α-olefin copolymer of component (B) may be one type copolymerized with ethylene, or two or more types copolymerized with ethylene.

[0054] In addition to ethylene units and α-olefin units, the ethylene-α-olefin copolymer of component (B) may contain other monomer units, such as monomer units based on non-conjugated dienes (non-conjugated diene units). Examples of such non-conjugated dienes include linear non-conjugated dienes such as 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene; and cyclic non-conjugated dienes such as cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, and 6-chloromethyl-5-isopropenyl-2-norbornene. Preferable are 5-ethylidene-2-norbornene and dicyclopentadiene.

[0055] Specific examples of component (B) used in the thermoplastic elastomer composition of the present invention include ethylene-α-olefin copolymers such as ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-propylene-1-butene copolymer, ethylene-propylene-1-hexene copolymer, and ethylene-propylene-1-octene copolymer.

[0056] Component (B) may be an ethylene-α-olefin random copolymer, which is a random copolymer of ethylene and an α-olefin, or an ethylene-α-olefin block copolymer containing a polymer block of ethylene and a block of an ethylene-α-olefin copolymer. In one embodiment, component (B) can include at least one selected from the group consisting of ethylene-α-olefin random copolymers and ethylene-α-olefin block copolymers.

[0057] The melt flow rate of component (B) (measurement temperature 190°C, measurement load 21.18N) is not limited, but is usually 10 g / 10 min or less. From the viewpoint of strength, it is preferably 8.0 g / 10 min or less, more preferably 5.0 g / 10 min or less, and even more preferably 3.0 g / 10 min or less. The melt flow rate of component (B) (measurement temperature 190°C, measurement load 21.18N) is usually 0.01 g / 10 min or more. From the viewpoint of flowability, it is preferably 0.05 g / 10 min or more, and even more preferably 0.10 g / 10 min or more. The melt flow rate of component (B) is measured in accordance with ISO 1133 under conditions of a measurement temperature of 190°C and a measurement load of 21.18 N.

[0058] From the viewpoint of low-temperature impact resistance, the density of component (B) is preferably 0.880 g / cm 3 or less, more preferably 0.870 g / cm 3 On the other hand, the lower limit is not particularly limited, but is usually 0.850 g / cm 3 That's all.

[0059] Component (B) can be synthesized according to the methods disclosed in JP-A Nos. 2007-529617, 2008-537563, and 2008-543978. For example, component (B), an olefin-based block copolymer containing a polymer block of ethylene and a block of an ethylene-α-olefin copolymer, can be produced by preparing a composition containing a mixture or reaction product obtained by combining a first olefin polymerization catalyst with a second olefin polymerization catalyst capable of preparing a polymer having different chemical or physical properties from the polymer prepared by the first olefin polymerization catalyst under equivalent polymerization conditions, and a chain shuttling agent, and then contacting the composition with ethylene and an α-olefin under addition polymerization conditions.

[0060] The polymerization of component (B) is preferably carried out by a continuous solution polymerization method. In this method, catalyst components, a chain shuttling agent, monomers, and optionally a solvent, an auxiliary, a scavenger, and a polymerization aid are continuously fed into a reaction zone, and a polymer product is continuously removed therefrom. The block length can be varied by controlling the ratio and type of the catalyst, the ratio and type of the chain shuttling agent, the polymerization temperature, etc.

[0061] Other conditions for the synthesis of the olefin block copolymer of component (B) are disclosed in JP-A Nos. 2007-529617, 2008-537563, and 2008-543978.

[0062] As component (B), commercially available products can be used, such as Engage (registered trademark), Engage (registered trademark)-XLT series, and INFUSE (registered trademark) series manufactured by Dow Chemical Company, and Solumer (registered trademark) manufactured by SK Corporation.

[0063] The thermoplastic elastomer composition according to this embodiment may contain only one type of component (B), or may contain two or more types that differ in monomer unit composition, physical properties, and the like.

[0064] In the thermoplastic elastomer composition according to this embodiment, the content of component (B) is preferably 20 to 60% by mass, more preferably 30 to 60% by mass, and even more preferably 30 to 50% by mass. A content of component (B) of 20% by mass or more is preferred from the viewpoint of impact resistance, and a content of 60% by mass or less is preferred in order to maintain the rigidity of the base material.

[0065] The content of component (B) is preferably 40 to 60 parts by mass, more preferably 43 to 57 parts by mass, and even more preferably 45 to 55 parts by mass, relative to 100 parts by mass of the total amount of components (A) and (B). When the content of component (B) is 40 parts by mass or more relative to 100 parts by mass of the total amount of components (A) and (B), it is preferred from the viewpoint of impact resistance, and when it is 60 parts by mass or less, it is preferred from the viewpoint of maintaining rigidity as a substrate.

[0066] (Component (C)) The thermoplastic elastomer composition according to this embodiment contains silicone oil as component (C), which functions as a lubricant that prevents the stickiness inherent to thermoplastic elastomers and contributes to improving mold releasability during molding.

[0067] In conventional laminates for automotive interiors, the cause of delamination between the thermoplastic elastomer layer and the adhesive layer is thought to be the blooming of lubricants, particularly lubricants centered on fatty acid amides, onto the surface of the thermoplastic elastomer layer. When fatty acid amides bloom, they bloom in a manner that covers the surface of the thermoplastic elastomer layer, forming a film-like structure. The bloomed lubricant film then prevents oxidation of the surface of the thermoplastic elastomer layer, resulting in poor adhesion between the adhesive layer and the thermoplastic elastomer layer, leading to delamination.

[0068] In contrast, the thermoplastic elastomer composition of this embodiment contains silicone oil as component (C), which functions as a lubricant. Even if the silicone oil bleeds to the surface, it tends to aggregate with other silicone oils. As a result, the entire surface of the thermoplastic elastomer layer is not covered by the bled silicone oil, which makes it easier for oxidation to proceed to the surface of the thermoplastic elastomer layer. This is thought to result in improved adhesion compared to when a fatty acid amide is used as a lubricant.

[0069] There are no particular restrictions on the type of substituent bonded to the siloxane main chain in the molecular structure of component (C), but among these, dimethyl silicone oil, methylphenyl silicone oil, or alkyl-modified silicone oil is preferably used. The viscosity of the silicone oil (measurement condition: 25°C) which is the component (C) is preferably 1 to 10,000 mm 2 / s, more preferably 10 to 1000 mm 2 / s. The viscosity of silicone oil is 1mm 2 / s or more is preferable because it prevents the silicone oil from migrating to the surface of the molded product during molding, preventing it from feeling sticky to the touch. 2 / s or less is preferable because the silicone oil is kept adequately transferred to the surface of the molded product, and mold releasability is maintained.

[0070] Commercially available products can be used as component (C) of the thermoplastic elastomer composition according to this embodiment. The silicone oil in component (C) can be procured from the manufacturers listed below and can be selected appropriately. Commercially available products include KF96-10cs, KF96-100cs, and KF96-1000cs from Shin-Etsu Chemical Co., Ltd., the SH200 series from Dow-Toray Industries, Inc., and the AK series from Wacker Asahi Kasei Silicones.

[0071] The thermoplastic elastomer composition according to this embodiment may contain only one type of component (C), or may contain two or more types with different compositions, physical properties, and the like.

[0072] In the thermoplastic elastomer composition according to this embodiment, the content of component (C) is preferably 0.1 to 5 mass%, more preferably 0.1 to 1 mass%, and even more preferably 0.2 to 0.5 mass parts. A content of component (C) of 0.1 mass% or more is preferred because it provides sufficient improvement in mold releasability, while a content of 5 mass% or less maintains adequate mechanical strength of the resulting composition and is also preferred from an economical standpoint. Furthermore, when using this silicone oil, it may be kneaded into the thermoplastic resin beforehand to improve the silicone oil's dispersibility and workability.

[0073] The content of component (C) is preferably 0.1 to 5 parts by mass, more preferably 0.1 to 1 part by mass, even more preferably 0.1 to 0.5 parts by mass, and particularly preferably 0.2 to 0.5 parts by mass, relative to 100 parts by mass of the total of components (A) and (B). When the content of component (C) is 0.1 part by mass or more, the improvement in mold releasability is sufficient, which is preferable, and when it is 5 parts by mass or less, the mechanical strength of the resulting composition is maintained at an appropriate level, which is also preferable from an economical standpoint.

[0074] (Other ingredients) Furthermore, in addition to the components described above, the thermoplastic elastomer composition according to this embodiment may contain optional components such as the following additives and polymers other than components (A) to (C) (hereinafter referred to as "other polymers") according to various purposes, within the scope of not significantly impairing the effects of the present invention.

[0075] Examples of optional components include various additives such as colorants, antioxidants, heat stabilizers, light stabilizers, UV absorbers, neutralizing agents, lubricants, antifogging agents, antiblocking agents, slip agents, flame retardants, dispersants, antistatic agents, conductivity imparting agents, metal deactivators, molecular weight modifiers, antibacterial agents, and fluorescent brighteners. For example, the antioxidant is used in an amount of 0.01 to 0.5 parts by mass per 100 parts by mass of the total amount of components (A) to (C). It is preferable that the thermoplastic elastomer composition according to this embodiment does not contain a fatty acid amide as a lubricant.

[0076] Examples of other polymers that may be contained in the thermoplastic elastomer composition according to this embodiment include styrene-based thermoplastic elastomers, polyesters, polyamides, styrene polymers, acrylic polymers, polycarbonates, polyvinyl chloride, and various other elastomers. The other polymers listed above may be contained alone or in combination of two or more. When a styrene-based thermoplastic elastomer is used, it is preferable to further use a hydrocarbon-based rubber softener.

[0077] (Characteristics of Thermoplastic Elastomer Composition) The melt flow rate of the thermoplastic elastomer composition according to this embodiment is preferably 2 g / 10 min or more, more preferably 3.5 g / 10 min or more, and even more preferably 5 g / 10 min or more, from the viewpoint of fluidity, i.e., ease of filling into a mold. To prevent deterioration of appearance due to the formation of flash, the melt flow rate is preferably 15 g / 10 min or less, more preferably 13.5 g / 10 min or less, and even more preferably 12 g / 10 min or less. The melt flow rate of the thermoplastic elastomer composition is measured in accordance with ISO 1133 at a measurement temperature of 230°C and a measurement load of 21.18 N. In one embodiment, the melt flow rate of the thermoplastic elastomer composition may be 2 to 15 g / 10 min.

[0078] [Adhesive layer] The laminate for automobile interior use according to this embodiment includes an adhesive layer. The adhesive layer preferably contains at least one of polyurethane, polyethylene, and polypropylene, more preferably polyurethane. The adhesive layer may contain polyurethane foam, polyethylene foam, or polypropylene foam, each of which is foamed from these materials, more preferably polyurethane foam.

[0079] [Other layers] The laminate for automobile interior use according to this embodiment may include other layers in addition to the thermoplastic elastomer layer and adhesive layer described above.

[0080] Examples of other layers include an outermost layer and a primer layer. The laminate for automobile interior use according to this embodiment may include, for example, an outermost layer, and may be configured in this order: the outermost layer, an adhesive layer, and a thermoplastic elastomer layer.

[0081] <Method of producing thermoplastic elastomer composition> The thermoplastic elastomer composition according to the present embodiment can be produced by kneading components (A) to (C) and other components in a conventional manner using a conventional extruder, Banbury mixer, roll, Brabender Plastograph, Kneader Brabender, or the like. Among these production methods, it is preferable to use an extruder, particularly a twin-screw extruder. When producing the thermoplastic elastomer composition according to the present embodiment by kneading using an extruder or the like, it can be produced by melt-kneading in a state heated to typically 160 to 240°C, preferably 180 to 220°C.

[0082] The produced thermoplastic elastomer composition can be made into a molded article using a conventional injection molding method or, as necessary, various molding methods such as gas injection molding, injection compression molding, and short shot foam molding, and the base material portion of the laminate for automotive interior according to this embodiment can be produced. In one embodiment, it is particularly preferable to produce the molded article by injection molding, and the molding conditions for injection molding are as follows. In one embodiment, the molding temperature when injection molding the thermoplastic elastomer composition is generally 150 to 300°C, and preferably 160 to 280°C. The injection pressure is generally 5 to 100 MPa, and preferably 10 to 80 MPa. The mold temperature is generally 0 to 80°C, and preferably 20 to 60°C.

[0083] The obtained thermoplastic elastomer molded article can be used as a laminate for automobile interiors by laminating an adhesive layer on the surface of a substrate. When laminating the adhesive layer on the surface of the substrate, the surface of the thermoplastic elastomer molded article may be subjected to an oxidation treatment such as burner treatment, plasma treatment, or corona treatment. The lamination can be performed, for example, by thermocompression bonding. After the oxidation treatment, various primers may be applied to the oxidation-treated side of the thermoplastic elastomer, if necessary.

[0084] <Instrument panel> The instrument panel according to this embodiment is made of the above-described laminate for automobile interior use. The preferred embodiments of the laminate for automotive interior use and the thermoplastic elastomer layer and adhesive layer contained therein are as described above. Furthermore, the preferred embodiments of the thermoplastic elastomer composition constituting the thermoplastic elastomer layer are also as described above. Additionally, the thermoplastic elastomer layer may be used as an airbag housing cover layer. An outermost layer, which will serve as the surface of the instrument panel, can be laminated on the adhesive layer laminated on the thermoplastic elastomer layer. Materials that can be used for this outermost layer include polypropylene, a mixture of polypropylene and talc, polyvinyl chloride, polyurethane, and soft thermoplastic elastomers with an A hardness (ISO 7619) of 30 to 90. [Example]

[0085] The present invention will be described in more detail with reference to examples and comparative examples. It should be noted that the present invention is not limited to the following examples, provided that the gist of the invention is not exceeded. The values ​​of various manufacturing conditions and evaluation results in the following examples represent preferred upper or lower limit values ​​in the embodiments of the present invention, and preferred ranges may be defined by combining the above-mentioned upper or lower limit values ​​with the values ​​of the following examples or values ​​between the examples.

[0086] The components used in the examples and comparative examples are as follows.

[0087] [Component (A): Propylene-based polymer] A-1 Novatec® PP BC3B, a propylene-based block copolymer (obtained by polymerizing propylene homopolymer in the first step and then polymerizing ethylene-propylene copolymer in the second step), manufactured by Japan Polypropylene Corporation MFR (ISO 1133): 9 g / 10 min (measurement conditions: 230°C, load 21.18 N) Propylene unit content: 92.5% by mass Ethylene unit content: 7.5% by mass Block (a1): Block (a2) = 85.5:14.5 (mass ratio)

[0088] [Component (B): Ethylene-α-olefin copolymer] B-1 Ethylene-1-octene copolymer rubber Dow Chemical Company Engage® 8150 MFR (ISO 1133): 0.5 g / 10 min (measurement conditions: 190°C, load 21.18 N)

[0089] [Component (C): Silicone oil] C-1 Shin-Etsu Chemical Co., Ltd. KF96-100cs Viscosity 100mm 2 / s (measurement conditions: 25°C) C-2 Shin-Etsu Chemical Co., Ltd. KF96-10cs Viscosity 10mm 2 / s (measurement conditions: 25°C) C-3 Shin-Etsu Chemical Co., Ltd. KF96-1000cs Viscosity 1000mm 2 / s (measurement conditions: 25°C)

[0090] [Component (X): Oleic acid amide] X-1 OPTISLIP VRX-BE-HU manufactured by Equus Japan Co., Ltd.

[0091] [Antioxidants] Irganox 1010 BASF Japan Ltd. Irganox 1010

[0092] [Light stabilizer] XT855FF BASF Japan XT855FF 770DF BASF Japan Ltd. Tinuvin 770

[0093] [Example 1] A mixed raw material was obtained by blending each component for 1 minute in a Henschel mixer according to the composition shown in Table 1. The mixed raw material was fed into a co-rotating twin-screw extruder ("TEX30α" manufactured by Kobe Steel, Ltd., L / D=45, number of cylinder blocks: 13) at a rate of 20 kg / h, and melt-kneaded by heating within the range of 160 to 210°C to produce pellets of the thermoplastic elastomer composition of Example 1.

[0094] [Examples 2 to 6, Comparative Examples 1 to 4] Pellets of the thermoplastic elastomer compositions of Examples 2 to 6 and Comparative Examples 1 to 4 were produced in the same manner as in Example 1, except that the blending compositions were changed to those shown in Table 1.

[0095] [Evaluation method] The thermoplastic elastomer compositions of Examples 1 to 6 and Comparative Examples 1 to 4 were evaluated as follows. The results are shown in Table 1.

[0096] (Mold releasability) The resulting thermoplastic elastomer composition was molded into 120mm square test pieces (3mm thick) using an in-line screw-type injection molding machine (Toshiba Machine Co., Ltd., "IS130") at an injection pressure of 50MPa, a cylinder temperature of 220°C, and a mold temperature of 40°C. After molding, the test pieces were manually removed from the mold and their releasability was checked. The evaluation was based on a 5-point scale, with a rating of "1" indicating that the test piece remained on the fixed side when the mold opened (very poor release from the mold) and a rating of "5" indicating that the test piece moved together with the movable side and then fell off due to the ejector pin (too good releasability). From the viewpoint of production efficiency, a release property of 3 to 4 is appropriate.

[0097] (Liquidity) The obtained thermoplastic elastomer composition was measured at a temperature in accordance with ISO 1133. The melt flow rate measured under conditions of 230°C and a measuring load of 21.18 N was evaluated as fluidity. From the viewpoint of the flowability of the thermoplastic elastomer composition and the appearance of the resulting molded article, the flowability is preferably 2 to 15 g / 10 min.

[0098] (wettability) Using the same method as for the evaluation of releasability, 120mm square test pieces were molded. Samples were prepared immediately after molding, 1 day after molding, 5 days after molding, and 10 days after molding. One surface of each sample was subjected to oxidation treatment using a corona surface treatment device (manufactured by Suga Test Instruments Co., Ltd.). The oxidized surface was then evaluated for wettability using a mixture for wetting tension testing (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) in accordance with JIS K6768. The larger the value, the more successfully the surface was kept wet even with a reagent with a high surface tension. In other words, the larger the wettability value, the more progressed the oxidation treatment of the surface. From the viewpoint of stability as an interior material, the larger the wettability value, the more preferable.

[0099] (Adhesive strength) Using the same method as for the wettability evaluation, the surface of each 120mm square specimen was subjected to an oxidation treatment immediately after molding, one day after molding, and 10 days after molding. A mixture of 100 parts by weight of Leatheroid LU-4304 (Dainichiseika Chemicals Co., Ltd.), a urethane resin adhesive, and 5 parts by weight of Leatheroid LU-3017(c) (Dainichiseika Chemicals Co., Ltd.) was prepared and applied to one side of each obtained sample using a bar coater to a thickness of approximately 10 μm. The sample was then dried in an oven at 80°C for 6 hours and then left to stand at room temperature for 24 hours. A laminate was then created by thermally laminating polyurethane tape (12 mm wide) onto the adhesive-coated surface. The adhesive strength between the polyurethane tape and the thermoplastic elastomer layer of the obtained test piece was measured using an Autograph AG2000 (Shimadzu Corporation) in accordance with ISO 8510-2: 1990 by a 180-degree peel test method (test speed 50 mm / min, peel distance approximately 50 mm, maximum test force measured).The adhesive strength was used to evaluate the adhesion between the sheet made of the thermoplastic elastomer composition and the adhesive. From the viewpoint of the stability of the interior member, the higher the adhesive strength value, the more preferable.

[0100] [Table 1]

[0101] As shown in Table 1, the laminates obtained from the thermoplastic elastomer compositions of Examples 1 to 6 had no problems with releasability during molding. Furthermore, the wettability evaluation showed a result of 31 or more even after 5 days of curing following molding and corona treatment. The adhesive strength was also extremely high immediately after molding, reaching 20 N or more after 1 day and 10 N or more after 10 days. These results demonstrate that laminates comprising a thermoplastic elastomer layer and an adhesive layer exhibiting excellent releasability and high adhesive strength were obtained in Examples 1 to 6.

[0102] In contrast, the thermoplastic elastomer composition of Comparative Example 1 did not contain either component (C) or component (X), i.e., did not contain any lubricant. Therefore, although the wettability and adhesive strength of the resulting laminate were high, the releasability during molding was extremely poor. On the other hand, the thermoplastic elastomer compositions of Comparative Examples 2 to 4 contained component (X) as a lubricant, and although the resulting laminates had sufficient releasability during molding, the wettability evaluation showed low values ​​immediately after molding. In other words, it was found that the laminates obtained from the thermoplastic elastomer compositions of Comparative Examples 2 to 4 did not undergo sufficient oxidation treatment on the surface of the thermoplastic elastomer layer, and as a result, the adhesive strength of the test pieces decreased significantly after one day. [Industrial Applicability]

[0103] The laminate according to the embodiment of the present invention has improved adhesion between the adhesive layer and the thermoplastic elastomer layer and excellent releasability during molding, and therefore can be suitably used as a laminate for automobile interiors and an instrument panel made from the same.

Claims

1. A laminate for automotive interiors, comprising a thermoplastic elastomer layer made of a thermoplastic elastomer composition and an adhesive layer, wherein the thermoplastic elastomer composition contains the following components (A) to (C): Component (A): Propylene-based polymer Component (B): Ethylene / α-olefin copolymer Component (C): Silicone oil

2. 10. The automotive interior laminate of claim 1, wherein the adhesive layer comprises at least one of polyurethane, polyethylene, and polypropylene.

3. 10. The automotive interior laminate of claim 1, wherein the adhesive layer comprises a polyurethane.

4. 10. The automotive interior laminate of claim 1, wherein the adhesive layer comprises a polyurethane foam.

5. 2. The laminate for automotive interiors according to claim 1, wherein the component (A) comprises at least one selected from the group consisting of propylene homopolymers and propylene-based block copolymers.

6. 2. The laminate for automotive interiors according to claim 1, wherein component (A) comprises a propylene-based block copolymer.

7. 7. The laminate for automotive interior according to claim 6, wherein the propylene-based block copolymer comprises a block (a1) having a propylene unit content of 90 to 100% by mass and a block (a2) having a propylene unit content of 30 to 70% by mass and an ethylene unit content of 30 to 70% by mass.

8. 2. The laminate for automobile interiors according to claim 1, wherein the α-olefin of component (B) has 3 to 8 carbon atoms.

9. 2. The laminate for automotive interiors according to claim 1, wherein the component (B) comprises at least one selected from the group consisting of ethylene / α-olefin random copolymers and ethylene / α-olefin block copolymers.

10. The viscosity of the silicone oil of the component (C) (measurement condition: 25°C) is 1 to 10,000 mm ２ 2. The laminate for automotive interior use according to claim 1, wherein the viscosity is 100 MPa or less.

11. 2. The laminate for automotive interior according to claim 1, wherein the content of the component (C) in the thermoplastic elastomer composition is 0.1 to 0.5 parts by mass per 100 parts by mass of the total amount of the component (A) and the component (B).

12. 2. The laminate for automobile interiors according to claim 1, wherein the thermoplastic elastomer composition has a melt flow rate of 2 to 15 g / 10 min.

13. The laminate for an automotive interior according to claim 1, comprising an outermost layer.

14. The laminate for an automobile interior according to claim 13, which is composed in this order of the outermost layer, the adhesive layer, and the thermoplastic elastomer layer.

15. An instrument panel comprising the laminate for automobile interior use according to any one of claims 1 to 14.

16. 16. The instrument panel of claim 15, wherein the thermoplastic elastomer layer is an airbag housing cover layer.

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