JP2010215684A - Method for manufacturing thermoplastic elastomer composition, thermoplastic elastomer composition, foam, and laminated sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a thermoplastic elastomer composition which is capable of maintaining a high melt tension necessary for an expansion molding even after dynamic heat treatment and is capable of manufacturing a foam with a high expansion ratio. <P>SOLUTION: The method for manufacturing the thermoplastic elastomer composition comprises dynamic heat treating a mixture of (A) an ethylene-&alpha;-olefin-based copolymer rubber and (B) a first olefin-based thermoplastic resin having a melt tension at 210&deg;C and a taking-off speed of 2.0 m/min of 3.0 cN or more in the presence of (C) a crosslinker to thereby obtain a precursor, and adding to the obtained precursor a second olefinic thermoplastic resin (D) having a melt tension at 210&deg;C and a taking-off speed of 2.0 m/min of 3.0 cN or more. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a thermoplastic elastomer composition and a production method thereof, a foam and a production method thereof, a laminated sheet, a production method and an adhesion method thereof, and an image display device, and more specifically, foam molding even after dynamic heat treatment. A thermoplastic elastomer composition capable of producing a foam having a high expansion ratio while maintaining a necessary high melt tension and melt spreadability, allowing cross-linking to proceed uniformly and a foam having a high expansion ratio, and a foam thereof The present invention relates to a production method, a laminated sheet having excellent cushioning properties, a production method and an adhesion method thereof, and an image display device which is less likely to be broken or distorted.

  Foam molded products for interior and exterior parts such as internal insulators such as electronic equipment and information equipment, cushioning materials, dustproof materials, sound insulation materials, heat insulation materials, food packaging materials, clothing materials, building materials, automobiles and home appliances, etc. Is used. Such a foam-molded product is required to have characteristics such as cushioning properties and heat insulation properties from the viewpoint of ensuring its sealing property when assembled as a part.

  Olefin-based resin foams such as polyethylene and polypropylene are known as materials for foam molded articles, but these foams have a problem that they are not sufficient in terms of cushioning properties. As an attempt to solve such a problem, increasing the expansion ratio or softening the material itself by blending a rubber component or the like with an olefin resin has been performed. However, ordinary olefin resin foams have low tension at high temperatures, that is, low melt tension, and even when trying to obtain a high expansion ratio, the cell walls are broken during foaming, causing gas loss or cell coalescence. It happened. Therefore, it was difficult to obtain a soft foam with a high expansion ratio.

  As a solution to the above problem, 210 ° C. is obtained by dynamically heat-treating a mixture containing rubber and at least one of a thermoplastic resin and a thermoplastic resin composition in the presence of a crosslinking agent. Obtained by foaming a thermoplastic elastomer composition having a melt tension at a speed of 2.0 m / min of 5.0 cN or more and a compression set of 80% or less measured at 70 ° C. for 22 hours in accordance with JIS K6262. A foam is disclosed (see, for example, Patent Document 1). However, when the foam disclosed in Patent Document 1 is dynamically heat-treated, the thermoplastic resin is decomposed and deteriorated. As a result, the melt tension of the thermoplastic elastomer composition is lowered, and the expansion ratio is reduced. There was still room for improvement to make it higher.

  In order to solve this problem, an α-olefin-based crystalline thermoplastic resin and an α-olefin-based amorphous heat having a melt tension of less than 3.0 cN at 210 ° C. and a take-off speed of 2.0 m / min are used. A thermoplastic elastomer composition obtained by dynamically heat-treating a mixture containing at least one of a plastic resin in the presence of a crosslinking agent, an olefin resin, and an average particle size of 0.1 μm or more and less than 2.0 μm An olefin resin foam obtained by foaming an olefin resin composition containing at least a nucleating agent with carbon dioxide in a supercritical state is disclosed (for example, see Patent Document 2).

International Publication No. 2007/066584 Pamphlet JP 2007-291337 A

  However, the olefin resin foam disclosed in Patent Document 2 sometimes has to add a large amount of olefin resin having a high melt tension in order to increase the expansion ratio. Further, the conventional thermoplastic elastomer composition has a problem that the take-up speed when the resin is cut when the take-up speed of the molten resin is increased, that is, the melt ductility is low. When the melt spreadability is low, the expansion ratio is high, and it may be difficult to obtain a soft foam.

  The present invention has been made in view of such problems of the prior art, and the object is to maintain high melt tension and melt ductility necessary for foam molding even after dynamic heat treatment. The object of the present invention is to provide a thermoplastic elastomer composition capable of producing a foam having a high expansion ratio and a method for producing the same.

  Another object of the present invention is to provide a foam having a high expansion ratio and a method for producing the same.

  Furthermore, the place made into the subject of this invention is providing the laminated sheet excellent in cushioning properties, its manufacturing method, and its adhesion | attachment method.

  Another object of the present invention is to provide an image display device that is less likely to be broken or distorted.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that an olefinic thermoplastic resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-up speed of 2.0 m / min is dynamically heat-treated before and after the heat treatment. It has been found that the above-mentioned problems can be achieved by adding the processes over and over, and the present invention has been completed.

  That is, according to the present invention, the following thermoplastic elastomer composition and production method thereof, foam and production method thereof, laminated sheet, production method and adhesion method thereof, and image display device are provided.

  [1] (A) ethylene / α-olefin copolymer rubber and (B) a first olefin thermoplastic resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-off speed of 2.0 m / min. The mixture is dynamically heat-treated in the presence of a crosslinking agent (C) to obtain a precursor, and the obtained precursor has (D) a melt tension at 210 ° C. and a take-up speed of 2.0 m / min of 3. A method for producing a thermoplastic elastomer composition, comprising adding a second olefin-based thermoplastic resin that is 0 cN or more.

  [2] A thermoplastic elastomer composition produced by the method for producing a thermoplastic elastomer composition according to [1].

  [3] The thermoplastic elastomer composition according to [2], wherein the compression set measured under conditions of 70 ° C. and 22 hours is 60% or less in accordance with JIS K6262.

  [4] A foam obtained by foaming the thermoplastic elastomer composition according to [2] or [3].

  [5] A method for producing a foam in which the thermoplastic elastomer composition according to [2] or [3] is foamed with a supercritical fluid.

  [6] A step of blending 0.01 to 20 parts by mass of a chemical foaming agent with respect to 100 parts by mass of the thermoplastic elastomer composition according to [2] or [3] to obtain a chemical foaming agent mixed raw material; And foaming the obtained chemical foaming agent mixed raw material.

  [7] The method for producing a foam according to [5] or [6], further including a step of irradiating an electron beam.

  [8] A sheet-like base material made of the foam according to [4], and an adhesive layer having an adhesive surface made of an adhesive and disposed on at least one surface of the base material. Laminated sheet.

  [9] The laminated sheet according to [8], wherein the pressure-sensitive adhesive is at least one selected from the group consisting of an olefin polymer, a styrene polymer, an acrylic polymer, and a polyester polymer.

  [10] The laminated sheet according to [8] or [9], further including a release sheet disposed on the adhesive surface.

  [11] A step of obtaining a sheet-like base material comprising a foam obtained by foaming the thermoplastic elastomer composition by extruding the thermoplastic elastomer composition according to the above [2] or [3]; And a step of disposing an adhesive layer made of an adhesive and having an adhesive surface on at least one surface of the substrate.

  [12] A sheet-like base material comprising a foam obtained by extruding the thermoplastic elastomer composition according to the above [2] or [3] and an adhesive and foaming the thermoplastic elastomer composition. And forming a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive and having a pressure-sensitive adhesive surface on at least one surface of the base material.

  [13] A method for adhering a laminated sheet, comprising affixing an adhesive surface of an adhesive layer provided in the laminated sheet according to any one of [8] to [10] to a surface of an adherend.

  [14] An image display panel having a viewing surface, a transparent front plate protecting the image display panel disposed on the viewing surface at a predetermined interval, and between the image display panel and the transparent front plate An image display device comprising: the laminated sheet according to any one of [8] to [10], and a case that houses the image display panel, the transparent front plate, and the laminated sheet.

  According to the method for producing a thermoplastic elastomer composition of the present invention, it is possible to produce a foam having a high expansion ratio while maintaining high melt tension and melt ductility necessary for foam molding even after dynamic heat treatment. There exists an effect that a thermoplastic elastomer composition can be manufactured.

  In addition, the thermoplastic elastomer composition of the present invention has an effect that it can maintain a high melt tension and melt spreadability necessary for foam molding even after dynamically heat-treating and can produce a foam having a high expansion ratio. It is what you play.

  Furthermore, the foam of the present invention has an effect that the expansion ratio is high.

  Moreover, according to the manufacturing method of the foam of this invention, there exists an effect that a foam with a high expansion ratio can be manufactured.

  Furthermore, the laminated sheet of the present invention has an effect of being excellent in cushioning properties.

  Moreover, according to the manufacturing method of the lamination sheet of this invention, there exists an effect that the lamination sheet excellent in cushioning properties can be manufactured.

  Furthermore, according to the method for bonding laminated sheets of the present invention, there is an effect that a laminated sheet having excellent cushioning properties can be bonded.

  In addition, the image display device of the present invention has an effect that it is difficult to cause destruction or distortion.

It is a correlation diagram of the value of the expansion ratio of the foam with respect to the melt tension of the olefin type thermoplastic resin used at the 1st process. It is a correlation diagram of the value of the expansion ratio of the foam with respect to the melt tension of the olefin type thermoplastic resin used at the 2nd process.

  Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments, and based on ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. It should be understood that modifications, improvements, and the like appropriately added to the embodiments described above fall within the scope of the present invention.

I. Method for Producing Thermoplastic Elastomer Composition The method for producing the thermoplastic elastomer composition of the present invention comprises ethylene / α-olefin copolymer rubber (hereinafter also referred to as “component (A)”), 210 ° C., take-off speed. A mixture containing a first olefinic thermoplastic resin (hereinafter also referred to as “component (B)”) having a melt tension of 2.0 cN or more at 2.0 m / min is used as a crosslinking agent (hereinafter referred to as “component (C)”. Is also heat-treated in the presence of (hereinafter also referred to as “first step”), and the resulting precursor is melt tensioned at 210 ° C. and take-up speed of 2.0 m / min. Is a method including adding a second olefinic thermoplastic resin (hereinafter also referred to as “component (D)”) having a viscosity of 3.0 cN or more (hereinafter also referred to as “second step”).

1 First Step The first step includes an ethylene / α-olefin copolymer rubber and a first olefin thermoplastic resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-off speed of 2.0 m / min. In this step, the mixture is dynamically heat-treated in the presence of a crosslinking agent to obtain a precursor.

(1) Mixture The mixture includes an ethylene / α-olefin copolymer rubber and a first olefin thermoplastic resin. The mass ratio of the component (A) and the component (B) contained in the mixture is preferably (A) component / (B) component = 95/5 to 20/80, and 90/10 to 20/80. Is more preferable, and 90/10 to 30/70 is particularly preferable. When the component (A) is less than 20% by mass and the component (B) is more than 80% by mass, the rubber elasticity of the foam may decrease. On the other hand, when the component (A) is more than 95% by mass and the component (B) is less than 5% by mass, the precursor phase structure is a good sea-island structure that is characteristic of dynamic crosslinking (the component (B) , (A) component is less likely to be islands), and fluidity and moldability may be reduced.

(I) Ethylene / α-olefin copolymer rubber The ethylene / α-olefin copolymer rubber is composed of a structural unit derived from ethylene (hereinafter, also referred to as “ethylene unit”) and a structural unit derived from an α-olefin ( Hereinafter, it is not particularly limited as long as it is a copolymer rubber containing “α-olefin unit”. Accordingly, the ethylene / α-olefin copolymer rubber is composed of a constituent unit derived from another monomer (hereinafter referred to as “other monomer” in addition to the binary copolymer rubber containing an ethylene unit and an α-olefin unit. It may be a terpolymer rubber containing a “body unit”). The ethylene / α-olefin copolymer rubber may be used alone or in combination of two or more.

(Ethylene unit)
The content ratio of the ethylene unit is preferably 35 to 90 mol%, more preferably 40 to 90 mol%, and particularly preferably 45 to 85 mol% with respect to the ethylene / α-olefin copolymer rubber. preferable. When the content ratio of the ethylene unit is less than 35 mol%, the mechanical strength may be insufficient. On the other hand, if it exceeds 90 mol%, flexibility may be insufficient.

(Α-olefin unit)
Specific examples of the α-olefin include propylene, 1-butene, 2-butene, isobutene, 1-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 1 -Hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-undecene and the like. Among these, propylene, 1-butene, and 1-octene are preferable. In addition, these alpha olefins may be used individually by 1 type, and may be used in combination of 2 or more type.

  The content ratio of the α-olefin unit is preferably 5 to 65 mol%, more preferably 10 to 45 mol%, and more preferably 15 to 40 mol% with respect to the ethylene / α-olefin copolymer rubber. Is particularly preferred. When the content ratio of the α-olefin unit is less than 5 mol%, it is difficult to exhibit desired rubber elasticity. On the other hand, if it exceeds 65 mol%, the durability may decrease.

(Other monomer units)
Examples of other monomers include non-conjugated diene monomers. Specific examples of the non-conjugated diene monomer include linear acyclic diene compounds such as 1,4-hexadiene, 1,5-hexadiene, and 1,6-hexadiene; 5-methyl-1,4-hexadiene 3,7-dimethyl-1,6-octadiene, 5,7-dimethyl-1,6-octadiene, 3,7-dimethyl-1,7-octadiene, 7-methyl-1,6-octadiene, dihydromyrcene Branched acyclic diene compounds such as tetrahydroindene, methyltetrahydroindene, dicyclopentadiene, bicyclo [2.2.1] -hepta-2,5-diene, 5-methylene-2-norbornene, 5-ethylidene- 2-norbornene, 5-propenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5-cyclohexylidene-2-norbol Emissions, alicyclic diene compounds such as 5-vinyl-2-norbornene. Among these, 1,4-hexadiene, dicyclopentadiene, and 5-ethylidene-2-norbornene are preferable. In addition, a nonconjugated diene monomer may be used individually by 1 type, and may be used in combination of 2 or more type.

  When the ethylene / α-olefin copolymer rubber has other monomer units, the content ratio of the other monomer units is 15 mol% or less with respect to the ethylene / α-olefin copolymer rubber. Is preferable, and it is still more preferable that it is 1-12 mol%. When the content ratio of other monomer units is more than 15 mol%, durability may be lowered.

  The ethylene / α-olefin copolymer rubber is halogenated in which some of the hydrogen atoms in the molecule of the ethylene / α-olefin copolymer rubber have been replaced with halogen atoms such as chlorine and bromine atoms. A copolymer rubber is preferred.

  The ethylene / α-olefin copolymer rubber is also preferably a graft copolymer rubber obtained by polymerizing an unsaturated monomer with the ethylene / α-olefin copolymer rubber described so far. Specific examples of unsaturated monomers include vinyl chloride; vinyl acetate; (meth) acrylic acid; (meth) acrylic acid methyl, (meth) acrylic acid glycidyl, and (meth) acrylic acid derivatives such as (meth) acrylamide. Maleic acid; maleic acid derivatives such as maleic anhydride, maleimide and dimethyl maleate; and conjugated diene compounds such as butadiene, isoprene and chloroprene.

  Further, the ethylene / α-olefin copolymer rubber is preferably an oil-extended rubber obtained by adding a mineral oil softener to the ethylene / α-olefin copolymer rubber described so far. Such oil-extended rubber is easy to handle. Therefore, it is preferable to use the oil-extended rubber as the ethylene / α-olefin copolymer rubber because the production of the thermoplastic elastomer composition becomes easy. The ratio of the ethylene / α-olefin copolymer rubber and the mineral oil softener contained in the oil-extended rubber is 20 to 80% by mass when the total oil-extended rubber is 100% by mass. It is preferably 25 to 75% by mass, more preferably 30 to 70% by mass.

  The ethylene / α-olefin copolymer rubber can be prepared, for example, by polymerizing ethylene and α-olefin, and if necessary, other monomers in the presence of a catalyst and a solvent. The polymerization method is not particularly limited, and may be a conventionally known method. Specific examples include cationic polymerization, anionic polymerization, and radical polymerization. Among these, anionic polymerization is preferable. In addition, the catalyst is not particularly limited, and may normally be used for a polymerization reaction.

  The crystallinity of the ethylene / α-olefin copolymer rubber by X-ray diffraction measurement is preferably 20% or less, and more preferably 15% or less. When the crystallinity of the ethylene / α-olefin copolymer rubber is more than 20%, flexibility may be lowered.

  The intrinsic viscosity of the ethylene / α-olefin copolymer rubber (measured in decalin solvent at 135 ° C.) is preferably 1.0 to 9.0 dl / g, and preferably 2.0 to 9.0 dl / g. Is more preferable, and it is especially preferable that it is 3.0-8.0 dl / g. When the intrinsic viscosity is less than 1.0 dl / g, for example, when an oil-extended rubber is used as the ethylene / α-olefin copolymer rubber, the mineral oil softener bleeds out from the precursor, and the rubber elasticity is reduced. May decrease. On the other hand, if the intrinsic viscosity is more than 9.0 dl / g, the moldability may not be good.

(Ii) First olefin-based thermoplastic resin The first olefin-based thermoplastic resin is a resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-off speed of 2.0 m / min. The melt tension of the first olefin-based thermoplastic resin at 210 ° C. and a take-off speed of 2.0 m / min is 3.0 cN or more, preferably 5.0 cN or more, and more preferably 8.0 cN or more. preferable. If the melt tension is less than 3.0 cN, the melt tension of the thermoplastic elastomer composition at 210 ° C. and a take-off speed of 2.0 m / min may be less than 5.0 cN. Therefore, when foaming is performed, the foaming ratio is low, and it is difficult to form independent bubbles, and the shape of the formed bubbles may be uneven.

  The first olefin-based thermoplastic resin is a resin that affects foamability. Therefore, it is desirable that the thermoplastic elastomer composition is an olefin-based crystalline resin in order to obtain a predetermined melt tension.

(Olefin crystalline resin)
The olefin-based crystalline resin has a structural unit derived from an α-olefin as a main component. Since the first olefinic thermoplastic resin is such an olefinic crystalline resin, since the crystals, that is, the olefinic crystalline resin has a reinforcing effect, the mechanical strength of the resulting thermoplastic elastomer composition Has the advantage of improving. Here, in the olefin-based crystalline resin, “having a structural unit derived from an α-olefin as a main component” means a configuration derived from an α-olefin when the total amount of the olefin-based crystalline resin is 100% by mass. It means that the unit contains 80% by mass or more. In addition, it is preferable that the content rate of the structural unit derived from an alpha olefin is 90 mass% or more. When the content of the structural unit derived from the α-olefin is less than 80% by mass, the content of crystals, that is, the content of the structural unit having crystallinity of the olefin-based crystalline resin is decreased. There exists a possibility that the mechanical strength of a plastic elastomer composition may fall.

  The olefin-based crystalline resin may be a homopolymer of α-olefin, a copolymer of two or more α-olefins, or a copolymer with a monomer that is not an α-olefin. May be. Moreover, the mixture of 2 or more types of these different polymers and / or a copolymer may be sufficient.

  When the olefin-based crystalline resin is a copolymer, this copolymer may be a random copolymer or a block copolymer. However, in the case of a random copolymer, the total content of the structural units excluding the structural unit derived from α-olefin among the structural units in the random copolymer is 100% of the total amount of the random copolymer. It is preferable that it is 15 mass% or less with respect to mass%, and it is still more preferable that it is 10 mass% or less. If the total content of the structural units excluding the structural unit derived from α-olefin is more than 15% by mass, crystallization is hindered, so that sufficient crystallinity may not be obtained. In the case of a block copolymer, the total content of the structural units excluding the structural unit derived from α-olefin among the structural units in the block copolymer is 100% of the total amount of the block copolymer. It is preferable that it is 40 mass% or less with respect to mass%, and it is still more preferable that it is 20 mass% or less. When the total content of the structural units excluding the structural unit derived from α-olefin exceeds 40% by mass, the content of crystals, that is, the content of structural units having crystallinity of the olefin-based crystalline resin is decreased. Therefore, the mechanical strength of the resulting thermoplastic elastomer composition may be reduced.

The olefin-based crystalline resin is not particularly limited as long as it has crystallinity, but as the crystallinity of the olefin-based crystalline resin, the crystallinity by X-ray diffraction measurement is preferably 50% or more, It is more preferably 53% or more, and particularly preferably 55% or more. Here, the crystallinity is a value closely related to the density. That is, for example, in the case of polypropylene, the density of α-type crystals (monoclinic crystals) is 0.936 g / cm ³ , the density of smectic crystals (pseudo hexagonal crystals) is 0.886 g / cm ³ , and amorphous (atactic) ) The density of the component is 0.850 g / cm ³ . Also, in the case of poly-1-butene, the density of the isotactic crystal 0.91 g / cm ^3, the density of the amorphous (atactic) component is 0.87 g / cm ^3. From such a relationship between crystallinity and density, an olefinic crystalline resin having a crystallinity of 50% or more is an olefinic crystalline resin having a density of 0.89 g / cm ³ or more. The olefin-based crystalline resin preferably has a density of 0.90 to 0.94 g / cm ³ . When the crystallinity of the olefin-based crystalline resin is less than 50%, that is, when the density is less than 0.89 g / cm ³ , heat resistance, strength, and the like may be reduced.

The olefin-based crystalline resin preferably has a maximum peak temperature by differential scanning calorimetry, that is, a melting point (hereinafter also simply referred to as “T _m ”) of 100 ° C. or higher, and more preferably 120 ° C. or higher. preferable. If _Tm is less than 100 ° C, sufficient melt tension and strength may not be exhibited.

  The olefin-based crystalline resin is a resin obtained by polymerizing a monomer in the presence of an existing catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst. When a metallocene catalyst is used as the catalyst, the content of the low molecular weight component and the low crystalline component can be lowered, which is preferable from the viewpoint of improving the melt tension and strength.

  The olefin-based crystalline resin preferably has a melt flow rate (hereinafter also simply referred to as “MFR”) at a temperature of 230 ° C. and a load of 49 N of 0.1 to 100 g / 10 minutes, preferably 0.5 to 80 g / 10. More preferably, it is minutes. If the MFR is less than 0.1 g / 10 min, the kneading processability and extrusion processability of the thermoplastic elastomer composition may be insufficient. On the other hand, if it exceeds 100 g / 10 min, the strength of the molded product obtained from the thermoplastic elastomer composition may be lowered.

In view of the above, as an olefin-based crystalline resin, specifically, the degree of crystallinity is 50% or more, the density is 0.89 g / cm ³ or more, and the content rate of structural units derived from ethylene is 20 Or a copolymer of polypropylene, propylene and ethylene, having a _Tm of 100 ° C. or more, an MFR of 0.1 to 100 g / 10 min, and a melting point of 140 to 170 ° C. It is particularly preferable to use a copolymer of propylene, ethylene and 1-butene.

  In preparing the mixture, the component (A) and the component (B) may be used as they are, or those prepared as compositions containing the same or different additives may be used. The shape of the component (A) may be any of a bale shape, a crumb shape, a pellet shape, and a powder shape (including a crushed product of a bale rubber or a crumb rubber). Moreover, you may use combining several (A) component from which a shape differs.

(2) Precursor A precursor is obtained by dynamically heat-treating a mixture in the presence of a crosslinking agent. As used herein, “dynamic heat treatment” refers to both applying a shearing force and heating. And the precursor obtained by such dynamic bridge | crosslinking normally comprises what is called a sea-island structure in which (B) component is made into a sea phase, and (A) component is disperse | distributed as an island phase in this sea phase. To do. In addition, it is preferable to use at least one of a crosslinking assistant and a crosslinking accelerator together with the crosslinking agent because the crosslinking reaction can be performed gently and uniform crosslinking can be performed.

  As an apparatus for “dynamically heat-treating” the mixture, a melt-kneading apparatus or the like can be suitably used. The treatment by the melt kneader may be either a continuous type or a batch type. Specific examples of the melt kneading apparatus include an open type mixing roll, a non-open type Banbury mixer, a single screw extruder, a twin screw extruder, a continuous kneader, and a pressure kneader. Among these, continuous melt kneading apparatuses such as a single screw extruder, a twin screw extruder, and a continuous kneader are preferable from the viewpoints of economy, processing efficiency, and the like. Further, two or more continuous melt-kneading apparatuses having the same type or different types may be used in combination.

  The L / D ratio (ratio between the screw effective length L and the outer diameter D) of the twin screw extruder is preferably 30 or more, and more preferably 36 to 60. In addition, as the twin screw extruder, for example, an arbitrary twin screw extruder such as one in which two screws mesh or not mesh can be used, but the rotation direction of the two screws is the same direction. Are more preferable. As such a twin screw extruder, for example, a trade name “PCM” (manufactured by Ikegai Co., Ltd.), a trade name “KTX” (manufactured by Kobe Steel), a trade name “TEX” (manufactured by Nippon Steel Works), a product There is a name “TEM” (manufactured by Toshiba Machine Co., Ltd.), a product name “ZSK” (manufactured by Warner), and the like.

  The L / D ratio (ratio between the screw effective length L and the outer diameter D) of the continuous kneader is preferably 5 or more, and more preferably 10 or more. Examples of such a continuous kneader include a trade name “Mixtron KTX / LCM / NCM” (manufactured by Kobe Steel) and a trade name “CIM / CMP” (manufactured by Nippon Steel).

  The treatment temperature for the dynamic heat treatment is preferably 120 to 350 ° C, and more preferably 150 to 290 ° C. The treatment time is preferably 20 seconds to 320 minutes, more preferably 30 seconds to 25 minutes. Further, the shearing force to be applied is preferably 10 to 20000 / sec, more preferably 100 to 10,000 / sec in terms of shear rate.

(Iii) Crosslinking agent The type of crosslinking agent is not particularly limited, but at least ethylene / α-olefin copolymer is obtained by dynamic crosslinking at a temperature equal to or higher than the melting point of the first olefin thermoplastic resin. It is a compound that can crosslink rubber.

  Examples of the crosslinking agent include organic peroxides, phenol resins, sulfur, sulfur compounds, p-quinones, p-quinone dioxime derivatives, bismaleimide compounds, epoxy compounds, silane compounds, amino resins, polyols, polyamines, and triazines. There are compounds and metal soaps. Among these, organic peroxides and phenol resins are preferable. In addition, these crosslinking agents may be used individually by 1 type, and may be used in combination of 2 or more type.

  The amount of the crosslinking agent used is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and 1 to 10 parts by mass with respect to 100 parts by mass of the mixture. Is particularly preferred.

(Organic peroxide)
Specifically, as the organic peroxide, 1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, 2, 5-dimethyl-2,5-bis (t-butylperoxy) hexene-3, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, 2,2′-bis (t-butyl) Peroxy) -p-isopropylbenzene, dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxide, p-menthane peroxide, 1,1-bis (t-butylperoxy) -3,3 , 5-trimethylcyclohexane, dilauroyl peroxide, diacetyl peroxide, t-butyl peroxybenzoate, 2,4-dichlorobenzoyl peroxide, p-chlorobe Examples thereof include nzoyl peroxide, benzoyl peroxide, di (t-butylperoxy) perbenzoate, n-butyl-4,4-bis (t-butylperoxy) valerate, t-butylperoxyisopropyl carbonate, and the like. Among these, 1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne, 3,2,5-dimethyl-2,5 -Di (t-butylperoxy) hexane, α, α-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, and di-t-butyl peroxide are preferred. In addition, these organic peroxides may be used individually by 1 type, and may be used in combination of 2 or more type.

  When using an organic peroxide as a crosslinking agent, the amount of the organic peroxide used is preferably 0.05 to 10 parts by weight, and 0.1 to 5 parts by weight with respect to 100 parts by weight of the mixture. More preferably it is. If the amount used exceeds 10 parts by mass, the degree of crosslinking becomes excessively high, the molding processability may be lowered, and the mechanical properties of the precursor may be lowered. On the other hand, if it is less than 0.05 parts by mass, the degree of crosslinking may be insufficient, and the rubber elasticity and mechanical strength of the precursor may decrease.

  When an organic peroxide is used as the crosslinking agent, sulfur, sulfur compounds (powdered sulfur, colloidal sulfur, precipitated sulfur, insoluble sulfur, surface-treated sulfur, dipentamethylene thiuram tetrasulfide, etc.), oxime compounds (p -Quinone oxime, p, p'-dibenzoylquinone oxime, etc.), polyfunctional monomers (ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di) (Meth) acrylate, polyethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, diallyl phthalate, tetraallyloxyethane, triallyl cyanurate, N, N′-m-phenylenebismaleimide, N, N - toluylene bismaleimide, maleic anhydride, divinylbenzene, be used together with di (meth) zinc acrylate and the like) or the like. Among these, p, p'-dibenzoylquinone oxime, N, N'-m-phenylene bismaleimide, and divinylbenzene are preferable. These crosslinking aids may be used alone or in combination of two or more. N, N'-m-phenylenebismaleimide also has a property as a crosslinking agent, and can be used alone as a crosslinking agent.

  When an organic peroxide is used as the crosslinking agent, the amount of the crosslinking aid used is preferably 10 parts by mass or less, more preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the mixture. preferable. If the amount used exceeds 10 parts by mass, the degree of crosslinking becomes excessively high, the molding processability may be lowered, and the mechanical properties of the precursor may be lowered.

(Phenolic resin)
Specific examples of the phenol resin include a p-substituted phenol compound represented by the general formula (1), an o-substituted phenol / aldehyde condensate, an m-substituted phenol / aldehyde condensate, and a brominated alkylphenol / aldehyde condensate. Etc. Among these, p-substituted phenol compounds are preferable. These phenol resins may be used alone or in combination of two or more.

In general formula (1), A represents a hydroxyl group, a halogenated alkyl group, or a halogen atom, R ¹ independently represents a saturated hydrocarbon group having 1 to 15 carbon atoms, and s represents 0 to An integer of 10 is shown.

  The p-substituted phenol compound can be prepared, for example, by a condensation reaction between a p-substituted phenol and an aldehyde (preferably formaldehyde) in the presence of an alkali catalyst.

  A commercially available product may be used as the p-substituted phenol compound. Commercially available phenolic resins include, for example, trade name “Tactrol 201” (alkylphenol formaldehyde resin, manufactured by Taoka Chemical Co., Ltd.), trade name “Tactrol 250-I” (brominated alkylphenol formaldehyde resin having a bromination rate of 4%, Taoka Chemical Industry Co., Ltd.), trade name “Tactrol 250-III” (brominated alkylphenol formaldehyde resin, manufactured by Taoka Chemical Industry Co., Ltd.), trade name “PR-4507” (manufactured by Gunei Chemical Industry Co., Ltd.), trade name “ST137X” ( Rohm & Haas), trade name “Sumilite Resin PR-22193” (manufactured by Sumitomo Durez), trade name “Tamanor 531” (made by Arakawa Chemical Industries), trade name “SP1059”, trade name “SP1045”, Product name “SP1055”, product name “SP1056” (above, Schenectady Etsu Chemical Co., Ltd.), there is a trade name of "CRM-0803" (manufactured by Showa Union Gosei Co.). Among these, “Tack roll 201” is preferable.

  When using a phenol resin as a crosslinking agent, it is preferable that the usage-amount of a phenol resin is 0.2-10 mass parts with respect to 100 mass parts of mixtures, and it is still more preferable that it is 0.5-5 mass parts. . If the amount used exceeds 10 parts by mass, the molding processability of the precursor may deteriorate. On the other hand, when it is less than 0.2 parts by mass, the degree of crosslinking is insufficient, and the rubber elasticity and mechanical strength of the precursor may be lowered.

  When a phenol resin is used as the crosslinking agent, it is preferable to use a crosslinking accelerator in combination for the purpose of adjusting the crosslinking rate. Examples of such crosslinking accelerators include metal halides (eg, stannous chloride, ferric chloride, etc.), organic halides (eg, chlorinated polypropylene, butyl bromide rubber, chloroprene rubber, etc.). . In addition to the crosslinking accelerator, it is more preferable to use a metal oxide such as zinc oxide or a dispersant such as stearic acid in combination.

  Moreover, a precursor can contain various additives as needed. Examples of additives that can be contained include softeners, nucleating agents, lubricants, anti-aging agents, heat stabilizers, light stabilizers such as HALS, weathering agents, metal deactivators, ultraviolet absorbers, and light stabilizers. , Stabilizers such as copper damage inhibitors, antibacterial agents, fungicides, dispersants, flame retardants, tackifiers, colorants such as titanium oxide, carbon black and organic pigments, metal powders such as ferrite, glass fibers , Inorganic fibers such as metal fibers, organic fibers such as carbon fibers and aramid fibers, composite fibers, inorganic whiskers such as potassium titanate whiskers, glass beads, glass balloons, glass flakes, mica, calcium carbonate, talc, silica, silicic acid Fillers such as calcium, hydrotalcite, kaolin, diatomaceous earth, graphite, pumice, evo powder, cotton flock, cork powder, barium sulfate, wood powder, etc. There is a thing like. Among these, it is preferable to contain a softener and a nucleating agent.

(Softener)
The softener improves processability and flexibility. Specific examples of the softener include petroleum oils such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt and petroleum jelly; coal tars such as coal tar and coal tar pitch; castor oil, linseed oil and rapeseed oil Fatty oils such as soybean oil and palm oil; waxes such as tall oil, beeswax, carnauba wax and lanolin; fatty acids such as ricinoleic acid, palmitic acid, stearic acid, barium stearate and calcium stearate; or metal salts thereof; petroleum resins , Synthetic polymer compounds such as coumarone indene resin and atactic polypropylene; ester compounds such as dioctyl phthalate, dioctyl adipate and dioctyl sebacate; microcrystalline wax, sub (factis), liquid polybutadiene, modified liquid polybutadiene, liquid thiocol Liquid polyisoprene, liquid polybutene, liquid ethylene · alpha-olefin copolymer and the like. Among these, paraffinic, naphthenic, aromatic mineral oils, liquid polyisoprene, liquid polybutene, and liquid ethylene / α-olefin copolymers are preferred, paraffinic mineral oil, liquid polyisoprene, liquid polybutene, liquid An ethylene / α-olefin copolymer is more preferred.

  The amount of the softener used is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and particularly preferably 120 parts by mass or less with respect to 100 parts by mass of the mixture. When the amount used exceeds 200 parts by mass, a dispersion failure may occur during the dynamic heat treatment.

(Nucleating agent)
The nucleating agent is used to easily adjust the cell diameter and obtain a foam having appropriate flexibility. Specifically, powders of inorganic compounds such as calcium carbonate, talc, mica, silica, titania and the like can be mentioned. It may be a surface-treated nucleating agent.

  The amount of the nucleating agent used is preferably 20 parts by mass or less, more preferably 0.01 to 15 parts by mass, and 0.1 to 10 parts by mass with respect to 100 parts by mass of the mixture. Is particularly preferred. The nucleating agent can be added to the molding machine as a master batch using, for example, polypropylene resin.

2 Second Step The second step is a step of adding a second olefinic thermoplastic resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-off speed of 2.0 m / min to the precursor. It is possible to produce a thermoplastic elastomer composition. The method for producing the thermoplastic elastomer composition is not particularly limited. For example, after mixing the precursor and the second olefinic thermoplastic resin with a Henschel mixer, a 40 mm single screw extruder is used, There is a method of extruding at 70 rpm.

(Iv) Second olefin-based thermoplastic resin Specific examples of the second olefin-based thermoplastic resin include those similar to the first olefin-based thermoplastic resin described in “(1) Mixture”. It is done. The second olefin-based thermoplastic resin may be the same as or different from the first olefin-based thermoplastic resin.

  The mass ratio of the precursor and the component (D) contained in the thermoplastic elastomer composition is preferably precursor / (D) component = 70/30 to 30/70, and 65/35 to 35/65. It is more preferable that the ratio is 60/40 to 40/60. When the precursor is less than 30% by mass and the component (D) is more than 70% by mass, the cushioning property of the foam may be inferior. On the other hand, if the precursor is more than 70% by mass and the component (D) is less than 30% by mass, the expansion ratio may be low.

II Thermoplastic Elastomer Composition The thermoplastic elastomer composition of the present invention is produced by “I Production Method of Thermoplastic Elastomer Composition”, that is, ethylene / α-olefin copolymer rubber and 210 ° C. A mixture containing the first olefinic thermoplastic resin having a melt tension of 3.0 cN or more at a speed of 2.0 m / min is dynamically heat-treated in the presence of a crosslinking agent (hereinafter also referred to as “dynamic crosslinking”). A precursor obtained by adding a second olefinic thermoplastic resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-off speed of 2.0 m / min to the obtained precursor. is there. Moreover, it is preferable that the compression set measured on condition of 70 degreeC and 22 hours based on JISK6262 is a thing of 60% or less. If the compression set is more than 60%, the foam may not have good rubber elasticity and cushioning properties when foamed.

  Further, the melt tension of the thermoplastic elastomer composition of the present invention at 210 ° C. and a take-off speed of 2.0 m / min is usually 5.0 cN or more, preferably 7.0 cN or more, preferably 8.0 cN or more. More preferably. When the melt tension is less than 5.0 cN, when foaming is performed, the expansion ratio is low, independent bubbles are hardly formed, and the shape of the formed bubbles may be uneven.

  Furthermore, the melt ductility at 210 ° C. of the thermoplastic elastomer composition of the present invention is usually 30 m / min or more, preferably 35 m / min or more, and more preferably 40 m / min or more. When the melt ductility is less than 30 m / min, when foaming is performed, the expansion ratio is low, independent bubbles are hardly formed, and the shape of the formed bubbles may be uneven.

  The melt flow rate (hereinafter also referred to as “MFR”) of the thermoplastic elastomer composition of the present invention is usually 0.1 to 100 g / 10 min under the conditions of 230 ° C. and a load of 98 N, and is 1.0 It is preferably ˜70 g / 10 min, more preferably 2.0 to 50 g / 10 min. If the MFR of the thermoplastic elastomer composition is less than 0.1 g / 10 min, the processability by various foam production methods may be insufficient. On the other hand, if it exceeds 100 g / 10 min, the foaming ratio is low when foamed, and it is difficult to form independent bubbles, and the shape of the formed bubbles is difficult to be uniform. Therefore, by using a thermoplastic elastomer composition having an MFR within a predetermined numerical range, it is possible to produce a foam having a high foaming ratio, a high closed cell property, and a uniform foamed cell shape.

  Furthermore, the hardness (duro D) of the thermoplastic elastomer composition of the present invention is usually 90 or less, preferably 80 or less, more preferably 70 or less. When the thermoplastic elastomer composition has a hardness (duro D) of more than 90, the resulting laminated sheet may have poor flexibility when foamed. Therefore, a laminated sheet having excellent cushioning properties can be produced by using a thermoplastic elastomer composition having a hardness (duro D) of a predetermined numerical value or less.

III Foam Next, the foam of the present invention will be described. The foam is obtained by foaming the thermoplastic elastomer composition of the present invention. Accordingly, the expansion ratio and closed cell property are high, the shape of the expanded cell is uniform, and the rubber elasticity, cushioning property, and surface appearance are excellent.

  The foam is obtained by foaming the thermoplastic elastomer composition of the present invention using a supercritical fluid or a chemical foaming agent. However, a foam foamed using a supercritical fluid is preferable because it has no odor and is excellent in recyclability and cushioning properties, compared with a foam foamed using a chemical foaming agent.

  The average cell diameter of the bubbles formed inside the foam is preferably 1 to 200 μm, more preferably 3 to 150 μm. If it is out of this range, the cushioning property may be lowered. In addition, an average cell diameter can be calculated | required with the enlarged micrograph of the cross section of a foam.

  The foam has a high expansion ratio and closed cell property, has a uniform cell shape, and is excellent in rubber elasticity, cushioning properties, and surface appearance. For example, an automobile interior such as an instrument panel or a glove box It can be suitably used as parts, automobile exterior parts such as weather strips, weak electrical parts, anti-vibration materials for electrical appliances, other industrial parts, building materials, sports equipment, and the like.

IV Foam Production Method Examples of the foam production method include, for example, a method of foaming the thermoplastic elastomer composition of the present invention with a supercritical fluid (hereinafter also referred to as “first production method”), A process of obtaining a chemical foaming agent mixed raw material by blending 0.01 to 20 parts by mass of a chemical foaming agent with respect to 100 parts by mass of the thermoplastic elastomer composition (hereinafter also referred to as “process (1)”), and And a step of foaming the chemical foaming agent mixed raw material (hereinafter also referred to as “step (2)”) (hereinafter also referred to as “second manufacturing method”).

1 1st manufacturing method First, the 1st manufacturing method is demonstrated concretely. The first production method is a method in which the thermoplastic elastomer composition of the present invention is melted to obtain a melt, a supercritical fluid is injected into the obtained melt, and then foamed.

  As the supercritical fluid, it is preferable to use carbon dioxide or nitrogen in a supercritical state. For example, in the case of carbon dioxide, a supercritical state can be obtained by setting the temperature to 31 ° C. or higher and the pressure to 7.3 MPa or higher. Carbon dioxide is in a supercritical state at a relatively low temperature and pressure, and has a high impregnation rate into the melt and can be injected at a high concentration, making it suitable for foam molding and forming fine bubbles. Can do.

  The first production method is not particularly limited as long as it is a method in which a supercritical fluid is injected into the obtained melt and then foamed, and may be performed by either a batch method or a continuous method. . Specific examples include extrusion molding, injection molding, and press molding.

  When the supercritical fluid is injected into the molten thermoplastic elastomer composition and uniformly mixed, the apparent viscosity is lowered, and thus the fluidity is improved. Further, when the thermoplastic elastomer composition is foamed using a supercritical fluid, the foaming ratio can be increased. Furthermore, it is easy to adjust the average cell diameter of the obtained foam.

2 Second Manufacturing Method Next, the second manufacturing method will be described. In the second production method, 0.01 to 20 parts by mass of a chemical foaming agent is blended with 100 parts by mass of the thermoplastic elastomer composition of the present invention to obtain a chemical foaming agent mixed raw material, and the obtained chemical foaming agent It is a manufacturing method including foaming a mixed raw material.

(1) Step (1)
Step (1) is a step of obtaining a chemical foaming agent mixed raw material by blending 0.01 to 20 parts by mass of the chemical foaming agent with respect to 100 parts by mass of the thermoplastic elastomer composition of the present invention. The chemical foaming agent is not particularly limited as long as it is used for foam molding of a resin material. For example, there are a pyrolytic foaming agent, a volatile foaming agent, a hollow particle foaming agent, and the like, which can be appropriately selected and used. Specifically, the trade name “Vini Hall AC # 3” (manufactured by Eiwa Kasei Kogyo Co., Ltd.), the trade name “Polyslen EE205” (manufactured by Eiwa Kasei Kogyo Co., Ltd.), and the trade name “EXPANCEL-092 (DU) -120” (Expans) Cell) and the like. In addition, these chemical foaming agents may be used individually by 1 type, and may be used in combination of 2 or more type.

  The compounding quantity of a chemical foaming agent is 0.01-20 mass parts with respect to 100 mass parts of thermoplastic elastomer compositions, Preferably it is 0.1-20 mass parts, Most preferably, it is 0.1-15. Part by mass. If the blending amount of the chemical foaming agent is less than 0.01 parts by mass, it is difficult to obtain a foam having a sufficient expansion ratio because it is too small. On the other hand, if it exceeds 20 parts by mass, the surface appearance is inferior, which is not preferable.

(2) Step (2)
Step (2) is a step of foaming the obtained chemical foaming agent mixed raw material. Although the foaming method is not particularly limited, methods such as extrusion foaming and injection foaming can be suitably used.

  Moreover, it is preferable that the manufacturing method of the foam of this invention is a method which further has the process of irradiating an electron beam. By irradiating the electron beam, the constituent components derived from the non-conjugated diene and α-olefin in the foam cause radical polymerization to form a three-dimensional crosslinked structure, and the elastic recovery property is further increased. Moreover, since crosslinking is performed by electron beam irradiation, there is no contamination with a crosslinking agent. The electron beam is permeable to the foam, and the degree of transmission depends on the thickness of the foam and the kinetic energy of the electron beam. Therefore, when the thickness of the foam and the energy of the electron beam are adjusted, the degree of crosslinking in the thickness direction of the foam becomes uniform.

  The electron beam acceleration voltage is preferably 100 to 2,000 kV, more preferably 200 to 1,000 kV. When the electron beam acceleration voltage is less than 100 kV, the proportion of electrons captured and absorbed in the surface layer portion is relatively increased, the number of electron beams transmitted through the foam is decreased, and a difference in the degree of cross-linking between the surface layer portion and the inside occurs. There is a case. On the other hand, if it exceeds 2,000 kV, the mechanical strength may decrease due to molecular cutting.

  The irradiation amount of the electron beam is preferably 10 to 1,000 kGy (Gy: gray, J / kg), more preferably 100 to 800 kGy. If it is less than 10 kGy, the degree of crosslinking may be insufficient. On the other hand, if it exceeds 1,000 kGy, the mechanical strength may decrease due to molecular cutting.

  The crosslinking effect by electron beam irradiation can be expressed by the product of the electron beam acceleration voltage and the dose. The product of the electron beam acceleration voltage (kV) and the irradiation dose (kGy) is preferably 1,000 to 2,000,000 (kV · kGy), more preferably 10,000 to 500,000 (kV · kGy). ). If it is less than 1,000 (kV · kGy), the proportion of electrons captured and absorbed by the surface layer portion is relatively increased, the number of electron beams that pass through the foam is decreased, and the degree of cross-linking between the surface layer portion and the inside is different. May occur. On the other hand, if it exceeds 2,000,000 (kV · kGy), the mechanical strength may decrease due to molecular cutting.

  The effect of improving rubber elasticity can be obtained only by electron beam crosslinking, but a crosslinking aid may be further added in the second step in order to further improve the effect of improving rubber elasticity. The amount of the crosslinking aid used is preferably 0.01 to 10 parts by mass and preferably 0.1 to 5 parts by mass with respect to 100 parts by mass in total of the precursor and the second thermoplastic resin. Further preferred. If the amount used exceeds 10 parts by mass, the effect of improving rubber elasticity is saturated, which is economically undesirable. On the other hand, when the amount used is 0.01 parts by mass or less, there may be a case where a further effect of improving rubber elasticity is not observed.

  Specific examples of the crosslinking aid include those similar to the crosslinking aid described in “2 Precursor”, and these may be used alone or in combination of two or more.

  When irradiating an electron beam, when the foam has a three-dimensional shape such as a tube shape, it is preferable to irradiate while rotating. By irradiating in this way, the entire surface of the foam can be irradiated uniformly with an electron beam and can be uniformly crosslinked. Moreover, it is preferable to irradiate both front and back surfaces in a three-dimensional shape such as a sheet shape or a film shape. Irradiation can be performed in a reciprocating manner, and the front and back surfaces can be alternately irradiated. Thereby, it can fully irradiate evenly on the surface of both sides.

  Moreover, irradiation may be performed continuously or in a batch manner. By subjecting the foam to electron beam irradiation in this way, compression set can be further reduced.

  The foam of the present invention thus produced has a high expansion ratio and closed cell property, a uniform cell shape, excellent rubber elasticity and cushioning properties, and very low compression set.

V laminated sheet The laminated sheet of this invention is equipped with the sheet-like base material which consists of a foam of this invention, and the adhesion layer which consists of an adhesive and which has an adhesive surface arrange | positioned on the at least 1 surface. Is. Moreover, it is preferable to provide the release sheet arrange | positioned on an adhesive surface as needed. Since the laminated sheet of the present invention includes a sheet-like substrate made of the foam of the present invention, the laminated sheet is excellent in cushioning properties.

(Adhesive layer)
As the pressure-sensitive adhesive used for the pressure-sensitive adhesive layer, a polymer having adhesiveness and capable of film forming can be used. Examples of such a polymer include olefin polymers, styrene polymers, acrylic polymers, polyester polymers, silicone polymers, urethane polymers, and the like. Among these, at least one selected from the group consisting of an olefin polymer, a styrene polymer, an acrylic polymer, and a polyester polymer is preferable.

  The thickness of the pressure-sensitive adhesive layer is appropriately selected according to the characteristics and application of the laminated sheet. From the viewpoint of molding processability and strength, for example, when used as a film, the thickness is preferably 1 to 500 μm, More preferably, it is 300 μm. Moreover, when using as a sheet | seat, it is preferable that it is 0.1-5 mm, and it is still more preferable that it is 0.5-3 mm. Moreover, the ratio of the thickness of the base material and the adhesive layer is appropriately selected according to the characteristics and application of the laminated sheet. For example, the base material / adhesive layer is in the range of 1 / 0.01 to 1/10. It is preferable that it is within a range of 1 / 0.01 to 1/5.

(Release sheet)
As the release sheet, for example, a sheet of polyester resin, silicone resin, polytetrafluoroethylene resin, or the like can be used.

  For disposing the release sheet, the adhesiveness of the pressure-sensitive adhesive layer may be used, and an appropriate adhesive or the like may be used as necessary.

  Moreover, the laminated sheet of this invention is manufactured using the foam of this invention which has favorable rubber elasticity and cushioning property, and shows the outstanding cushioning property. When the laminated sheet of the present invention is disposed between the viewing surface of the image display panel and the transparent front plate in a portable image display device or the like, the effect of preventing cracking of the image display panel due to external impact is obtained. It is possible to design the image display panel so as not to cause image distortion and case distortion. In addition, since the laminated sheet of the present invention has an adhesive surface, it does not require a separate adhesive when attached to a portable image display device or the like, making the attachment work simple and contributing to cost reduction. Furthermore, the laminated sheet of the present invention can prevent the intrusion and generation of dust from inside and outside the apparatus.

  The laminated sheet of the present invention can be particularly suitably used as an impact absorbing sheet for portable image display devices and the like, but its application is not particularly limited and can be used for a wide range of applications. For example, it is also useful as a dustproof material used when various members or parts are attached at predetermined positions. Examples of a member that can be attached using the laminated sheet of the present invention include an image display member provided in an image display device such as an electroluminescence display and a plasma display, and a camera and a lens attached to a mobile communication device. Can be mentioned. The laminated sheet of the present invention can also be used as a sealing material for preventing a toner cartridge used in an image forming apparatus such as a copying machine or a printer from leaking. The shape of the laminated sheet of the present invention is not particularly limited, and processing such as cutting and punching may be appropriately performed according to the purpose of use.

VI. Method for Producing Laminate Sheet One method for producing a laminate sheet of the present invention is a sheet-like substrate comprising a foam obtained by extruding the thermoplastic elastomer composition of the present invention and foaming the thermoplastic elastomer composition. And a step of disposing an adhesive layer made of an adhesive and having an adhesive surface on at least one surface of the substrate (hereinafter also referred to as “one manufacturing method”).

  As one manufacturing method, more specifically, after extruding a foam, a method of applying and drying a pressure-sensitive adhesive solution, and a method of extruding a foam and then heat-bonding the pressure-sensitive adhesive. .

  Another method for producing the laminated sheet of the present invention is a sheet-like substrate comprising a foam obtained by co-extrusion of the thermoplastic elastomer composition of the present invention and an adhesive and foaming the thermoplastic elastomer composition. The method includes forming a material and disposing an adhesive layer made of an adhesive and having an adhesive surface on at least one surface of the substrate (hereinafter also referred to as “other manufacturing method”).

  Among these production methods, other production methods are preferable from the viewpoint of productivity, using a coextrusion type extrusion molding machine, and simultaneously forming a sheet-like substrate made of a foam using a supercritical fluid, A method of disposing an adhesive layer is particularly preferable.

VII Laminate Sheet Adhesion Method The laminate sheet adhesion method of the present invention includes peeling the release sheet as necessary from the laminate sheet of the present invention, and attaching the adhesive surface of the adhesive layer to the surface of the adherend. Is the method. Further, by this bonding method, for example, the image display device of the present invention can be disposed between the image display panel and the transparent front plate.

VIII Image Display Device An image display device according to the present invention includes an image display panel having a viewing surface, a transparent front plate that protects the image display panel disposed on the viewing surface at a predetermined interval, and an image display panel. And a case for housing the image display panel, the transparent front plate, and the laminated sheet.

  As described above, the image display device of the present invention is a laminated sheet using the foam of the present invention that exhibits excellent adhesiveness and sealing properties even when different materials are used, and has good rubber elasticity and cushioning properties. Is obtained. For this reason, the image display device of the present invention has a transparent front plate bonded to the viewing surface of the image display panel while maintaining good sealing properties and rubber elasticity, and is extremely high quality.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified. Moreover, the measuring method of various physical-property values and the evaluation method of various characteristics are shown below.

  [Evaluation of various properties]: Using a pellet-shaped thermoplastic elastomer composition, melt flow rate (MFR) and melt tension were measured. Moreover, a test piece having a size of 120 mm × 120 mm × 2 mm was obtained by injection molding of the thermoplastic elastomer composition using an injection molding machine (trade name “N-100”, manufactured by Nippon Steel Works). Using the obtained test piece, hardness (duro A), hardness (duro D), tensile stress, tensile breaking strength, tensile breaking elongation, and compression set were measured.

  [Hardness (Duro A)]: Measured according to JIS K6253 and used as an index of flexibility.

  [Hardness (Duro D)]: Measured according to JIS K6253 and used as an index of flexibility.

  [Tensile stress (MPa)]: Measured as 100% modulus and 300% modulus according to JIS K6251.

  [Tensile breaking strength (MPa)]: Measured according to JIS C3305.

  [Tensile breaking elongation (%)]: Measured according to JIS K6251.

  [Melt flow rate (MFR) (g / 10 min)]: Measured under conditions of 230 ° C. and a load of 98 N in accordance with JIS K7210, and used as an index of fluidity.

[Melt tension (cN)]: A melt tension tester type II (manufactured by Toyo Seiki Seisakusho) was used, and the melt tension was measured under the following conditions.
Measurement temperature: 210 ° C
Orifice diameter: 2mmφ
Extrusion speed: 10.0mm / min
Take-off speed: 2.0 m / min

  [Melting stretchability (m / min)]: In the measurement of melt tension, when the take-up speed of the melted resin was increased, the take-up speed when the resin was cut was measured as melt stretchability.

  [Compression set (%)]: Measured under conditions of 70 ° C. and 22 hours in accordance with JIS K6262, and used as an index of rubber elasticity.

[Foaming ratio]: The specific gravity before foaming and the specific gravity after foaming of the thermoplastic elastomer composition were measured and calculated according to the following formula (2).
Foaming ratio = specific gravity before foaming / specific gravity after foaming (2)

  [Foam surface]: The surface appearance was visually observed, and the case where there was no waving or foam cell breakage on the surface was evaluated as “smooth”, and the case where there was waving or foam cell breakage was evaluated as “rough”. .

  [Foamed cell state]: Taking a magnified photograph (× 100) of the foam using a magnifying glass, the case where closed cells are formed is evaluated as “uniform”, and the case where open cells are formed is determined as “not good”. It was evaluated as “uniform”.

[Compression permanent set of foam (%)]: In a 23 ° C., 50% RH atmosphere, a sheet-like foam test piece was compressed to 25% of the thickness of the test piece using two compression plates. After holding for 22 hours, the test piece was released from the compressed state, the thickness of the test piece immediately after was measured, and the compression set was calculated according to the following formula (3).
Compression set = [thickness of test piece after release−initial thickness of test piece] / [thickness of test piece at 25% compression−initial thickness of test piece] × 100 (3)

[Shrinkage rate (%)]: The thickness of the sheet-like foam specimen after being held in a 100 ° C. atmosphere for 24 hours was measured, and the shrinkage rate was calculated according to the following formula (4).
Shrinkage rate = [initial thickness of test piece−thickness of test piece after 24 hours] / initial thickness of test piece × 100 (4)

  [Raw Material of Thermoplastic Elastomer Composition]: The thermoplastic elastomers of Examples and Comparative Examples were prepared using the raw materials shown below.

Component (A) Ethylene / propylene / 5-ethylidene-2-norbornene terpolymer (hereinafter also referred to as “EPDM”):
Ethylene content = 66%, propylene content = 29.5%, 5-ethylidene-2-norbornene content = 4.5%, intrinsic viscosity in decalin solvent at 135 ° C. = 4.7 dl / g.
Oil exhibition rubber:
EPDM polymer solution with paraffinic mineral oil (trade name “Diana Process Oil PW-90”, manufactured by Idemitsu Kosan Co., Ltd., pour point = −15 ° C., kinematic viscosity (40 ° C.) = 9.554 × 10 ⁻⁵ m ² / s) Oil-extended rubber was prepared by adding 100 parts (based on 100 parts of EPDM solids) and then removing the solvent.

(B) component and / or (D) component thermoplastic resin (1):
Crystalline polypropylene, trade name “Newstoren SH9000” (manufactured by Nippon Polypro), density = 0.90 g / cm ³ , MFR (temperature 230 ° C., load 21.2 N) = 0.3 g / 10 min, melt tension (temperature 210 C, take-off speed 2.0 m / min) = 20.0 cN.
Thermoplastic resin (2):
Crystalline polypropylene, trade name “B241” (manufactured by Prime Polymer Co., Ltd.), density = 0.90 g / cm ³ , MFR (temperature 230 ° C., load 21.2 N) = 0.5 g / 10 min, melt tension (temperature 210 ° C., (Take-off speed 2.0 m / min) = 5.6 cN.

Component (C) Crosslinking agent:
5-dimethyl-2,5-di (t-butylperoxy) hexane, trade name “Perhexa 25B-40” (manufactured by NOF Corporation).
Crosslinking aid (1):
Divinylbenzene (manufactured by Nippon Steel Chemical Co., Ltd.), purity: 81%.
Crosslinking aid (2):
Trimethylolpropane trimethacrylate, trade name “Light Ester TMP” (manufactured by Kyoeisha Chemical Co., Ltd.).

Additives Anti-aging agent:
Pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, trade name “Irganox 1010” (manufactured by Ciba Specialty Chemicals).

Other components Thermoplastic resin (3):
Crystalline polypropylene, trade name “NOVATEC FA3EB” (manufactured by Nippon Polypro), density = 0.90 g / cm ³ , MFR (temperature 230 ° C., load 21.2 N) = 10.5 g / 10 min, melt tension (temperature 210 ° C. , Take-up speed 2.0 m / min) = 1.3 cN.

1. Thermoplastic elastomer composition (Example 1)
(First step)
42 parts of oil-extended rubber as component (A), 8 parts of thermoplastic resin (1) as component (B), 0.6 part of crosslinking agent as component (C), 0.5 part of crosslinking aid (1), and 0.1 part of the anti-aging agent was put into a Henschel mixer and mixed for 30 seconds. Then, twin screw extruder (same direction complete meshing type screw, ratio (L) / (D) = 33.5 of length (L) of screw flight part and screw diameter (D), trade name “PCM45”, Extruded while performing heat treatment dynamically at a processing time of 220 ° C., residence time 1 minute 30 seconds, 400 rpm, and shear rate 400 / sec to obtain a pellet-like precursor.

(Second step)
After adding 51 parts of the obtained pellet-shaped precursor and 50 parts of the thermoplastic resin (1) as component (D) and mixing with a Henschel mixer, a 40 mm single screw extruder (length of screw flight part (L) and Using a ratio (L) / (D) = 28 with the screw diameter (D), trade name “FS40II”, manufactured by Ikegai Co., Ltd.), extrusion at 220 ° C. and 70 rpm to produce a pellet-shaped thermoplastic elastomer composition (1 ) Was manufactured. The manufactured thermoplastic elastomer composition (1) has a hardness (duro A) of 100, a hardness (duro D) of 56, a value of 100% modulus of 12.3 MPa, and a value of 300% modulus of 13 .4 MPa, tensile break strength is 22.0 MPa, tensile break elongation is 780%, MFR is 16.3 g / 10 min, melt tension is 13.0 cN, and melt ductility is 45 m / min. The compression set was 74%.

(Example 2)
Except that the thermoplastic resin (2) was used instead of the thermoplastic resin (1) as the component (B) in the first step in Example 1, the same operation as in Example 1 was performed, and pellet-like thermoplasticity An elastomer composition (2) was produced. Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (2).

Example 3
Except that the thermoplastic resin (2) was used instead of the thermoplastic resin (1) as the component (D) in the second step in Example 1, the same operation as in Example 1 was performed, and the pellet-like thermoplasticity An elastomer composition (3) was produced. Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (3).

Example 4
(First step)
42 parts of oil-extended rubber as component (A), 8 parts of thermoplastic resin (2) as component (B), 0.6 part of crosslinking agent as component (C), 0.5 part of crosslinking aid (1), and aging 0.1 part of the inhibitor was put into a Henschel mixer and mixed for 30 seconds. Then, twin screw extruder (same direction complete meshing type screw, ratio (L) / (D) = 33.5 of length (L) of screw flight part and screw diameter (D), trade name “PCM45”, Extruded while performing heat treatment dynamically at a processing time of 220 ° C., residence time 1 minute 30 seconds, 400 rpm, and shear rate 400 / sec to obtain a pellet-like precursor.

(Second step)
After adding 51 parts of the obtained pellet-shaped precursor and 45 parts of the thermoplastic resin (1) as the component (D) and mixing with a Henschel mixer, a 40 mm single screw extruder (length (L) of the screw flight part) Using a ratio (L) / (D) = 28 with a screw diameter (D), trade name “FS40II”, manufactured by Ikegai Co., Ltd.), extrusion at 220 ° C. and 70 rpm to produce a pellet-shaped thermoplastic elastomer composition (4 ) Was manufactured. Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (4).

(Example 5)
In the second step of Example 1, in addition to adding 51 parts of pellet precursor (1) and 50 parts of thermoplastic resin (1) as component (D), and further adding 1 part of crosslinking aid (2) Performed the same operation as Example 1, and manufactured the pellet-shaped thermoplastic elastomer composition (5). Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (5).

(Comparative Example 1)
The same operation as in Example 1 was performed except that the thermoplastic resin (3) was used as the other component instead of the thermoplastic resin (1) used as the component (B) in the first step in Example 1. It carried out and manufactured the pellet-shaped thermoplastic elastomer composition (6). Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (6).

(Comparative Example 2)
The same operation as in Example 1 was performed except that the thermoplastic resin (3) was used as the other component instead of the thermoplastic resin (1) used as the component (D) in the second step in Example 1. This was carried out to produce a pellet-shaped thermoplastic elastomer composition (7). Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (7).

(Comparative Example 3)
42 parts of oil-extended rubber as component (A), 58 parts of thermoplastic resin as component (B), 0.6 part of crosslinking agent as component (C), 0.5 part of crosslinking aid (1), and aging 0.1 part of the inhibitor was put into a Henschel mixer and mixed for 30 seconds. Then, twin screw extruder (same direction complete meshing type screw, ratio (L) / (D) = 33.5 of length (L) of screw flight part and screw diameter (D), trade name “PCM45”, Extruded while performing heat treatment dynamically at a processing time of 220 ° C., residence time 1 minute 30 seconds, 400 rpm, shear rate 400 / sec, using a pelletized thermoplastic elastomer composition (8) Manufactured. Table 2 shows the measurement results of various physical properties of the produced thermoplastic elastomer composition (8).

  As shown in Table 2, all of the thermoplastic elastomer compositions (1) to (5) have a melt tension of 8.0 cN or more and a melt ductility of 30 m / min or more, and a high melt tension and melt ductility. It turns out that it shows. In contrast, the thermoplastic elastomer composition (7) had a low melt tension. Further, the thermoplastic elastomer compositions (6) and (8) had a melt tension of 8 cN or more, but a melt ductility of less than 30 m / min.

2. Foam First production method [Method A]: 20 kg of a thermoplastic elastomer composition is introduced from a hopper of a tandem extrusion foam molding apparatus with a supercritical fluid supply device operating under the following conditions, and extruded and foamed. A foam was produced.
First molding machine: 20 kg of hopper input, 70 rpm, heater temperature (cylinder temperature) 240 ° C., cylinder pressure 15 MPa
Supercritical fluid: carbon dioxide, supercritical fluid supply (supercritical fluid concentration): 3%
Second molding machine: rotation speed 10 rpm, heater temperature (in-cylinder temperature), most upstream side 180 ° C., most downstream side 152 ° C., cylinder internal pressure 8 MPa
Die: Die temperature 152 ° C, pressure difference 8MPa

Second production method [Method A]: To 100 parts of the thermoplastic elastomer composition, 1 part of a wetting agent and 5 parts of a chemical foaming agent were added and stirred to obtain a master batch. The obtained master batch was converted into a single-screw extruder having a diameter of 40 mm (manufactured by Tanabe Plastics Co., Ltd., L / D = 28, 20 mm wide, 1.5 mm high die T-die, foaming temperature 220 ° C., rotation speed 20 rpm, full A foam was produced by placing in a flight screw) and extrusion foaming.

  [Method B]: To 100 parts of the thermoplastic elastomer composition, 1 part of a wetting agent and 5 parts of a chemical foaming agent were added and stirred to obtain a master batch. The obtained master batch is put into an injection molding machine (model “IS-90B”, manufactured by Toshiba Machine Co., Ltd., flat plate mold = length 100 mm, width 100 mm, height 3.5 to 6.5 mm, foaming temperature 220 ° C.). The foam was made by injection molding and foaming.

  [Method C]: With respect to 100 parts of the thermoplastic elastomer composition, 5 parts of a chemical foaming agent is added using an electric heating roll (manufactured by Kansai Roll Co., Ltd.) set at 160 ° C., and then molded into a sheet shape. A sheet made of a thermoplastic elastomer composition containing an agent was obtained. The obtained sheet was put into a 10 cm × 10 cm mold having a thickness of 0.5 cm, and the foam was manufactured by heating and pressing with a 220 ° C. electrothermal press molding machine for 10 minutes.

(Example 6)
Using the thermoplastic elastomer composition (1), foaming (1) was produced by foaming according to the first production method [Method A]. The foam (1) produced had a foaming ratio of “16 times”, a foam surface of “smooth”, and a foamed cell state of “uniform”.

(Examples 7-15, Comparative Examples 4-9)
While using the thermoplastic elastomer composition shown in Table 3, foams (2) to (16) were produced by foaming in accordance with the foaming method shown in Table 3. Table 3 shows the evaluation results of the foaming ratio, foam surface, and foam cell state of each foam produced. FIG. 1 shows a correlation diagram of the foaming ratio of the foam with respect to the melt tension value of the olefinic thermoplastic resin used in the first step, and FIG. 2 shows the correlation between the olefinic thermoplastic resin used in the second step. The correlation figure of the value of the expansion ratio of a foam with respect to the value of melt tension is shown. In addition, it shows below about the types (1)-(3) of the chemical foaming agent shown in Table 3.

Chemical foaming agent (1): Thermal decomposition type foaming agent, trade name “Vinifer AC # 3” (manufactured by Eiwa Chemical Industry Co., Ltd., thermal decomposition temperature: 208 ° C.)
Chemical foaming agent (2): Thermal decomposition type foaming agent, trade name “Polyslen EE206” (manufactured by Eiwa Chemical Industry Co., Ltd., thermal decomposition temperature: 200 ° C.)
Chemical foaming agent (3): Hollow particle type foaming agent, trade name “EXPANCEL-092 (DU) -120” (manufactured by EXPANCEL, maximum thermal expansion temperature: 180 ° C.)

  As shown in Table 3, the foams (1) to (5) obtained by the first production method have a high foaming ratio, a uniform foam cell state and a smooth foam surface, and a surface appearance. It was excellent. On the other hand, the foam (12) produced using the thermoplastic lastomer composition having low melt tension or melt spreadability has a low expansion ratio and is inferior in surface appearance.

  Moreover, as FIG.1 and FIG.2 shows, when the melt tension of the olefin type thermoplastic resin used for a 1st process and a 2nd process is 3.0 cN or more, a foam with a higher foaming ratio can be manufactured. . Moreover, when manufacturing the foam of an equivalent foaming magnification from foam (4) and (11), the addition amount of (D) component used for a 2nd process by using a (B) component for a 1st process. Therefore, the hardness of the thermoplastic elastomer composition can be lowered, and as a result, a foam having a good cushioning property can be produced. Furthermore, from the value of the foaming ratio of the foams (1) and (13), by adding a thermoplastic resin having a melt tension of 3.0 cN or more twice before and after the dynamic heat treatment, foaming with a higher foaming ratio is performed. It can be seen that the body can be manufactured.

  Furthermore, as can be seen from Table 3, the foams (6) to (10) obtained by the second production method have a higher expansion ratio than the foams (14) to (16), and the first step It can be seen that the higher the melt tension of the olefinic thermoplastic resin used in the second step, the more the foam can be produced.

(Example 16)
Using an electron beam irradiation apparatus (trade name “ESP300-60” (manufactured by Nissin High Voltage)) on both sides of the foam (1), the foam is irradiated with an electron beam under the conditions of an acceleration voltage of 300 kV and an irradiation dose of 500 kGy. Body (17) was obtained. Table 4 shows the compression set and shrinkage of the obtained foam (17).

(Example 17)
Except having used the foam (5) instead of the foam (1) in Example 16, operation similar to Example 16 was performed and the foam (18) was obtained. Table 4 shows the compression set and shrinkage rate of the obtained foam (18).

  As can be seen from Table 4, the foams (17) and (18) had smaller compression set and shrinkage than the foams (1) and (5) before being irradiated with the electron beam. Furthermore, the foam (18) to which the crosslinking aid was added in the second step had a smaller compression set and shrinkage than the foam (17) to which no crosslinking aid was added.

  By disposing the adhesive layer and the release sheet on at least one surface of the foam of the present invention, a laminated sheet having excellent cushioning properties can be produced. Moreover, since this laminated sheet can adhere the transparent front plate to the viewing surface of the image display panel while maintaining good sealing and rubber elasticity, it is typified by a TV, a personal computer, a mobile phone, etc. An extremely high quality image display device can be provided.

  The thermoplastic elastomer composition of the present invention is to produce a foam having a high expansion ratio, a high closed cell property and a uniform foam cell shape, and excellent rubber elasticity, cushioning properties, sealing properties, and surface appearance. It is something that can be done. Further, the foam of the present invention produced by foaming this thermoplastic elastomer composition is excellent in rubber elasticity, cushioning properties, sealing properties, and surface appearance. Furthermore, the laminated sheet of the present invention in which an adhesive layer and a release sheet are disposed on at least one surface of this foam has excellent cushioning properties. In addition, if the laminated sheet of the present invention is used, a transparent front plate can be adhered to the viewing side of the image display panel while maintaining good sealing properties and rubber elasticity. An extremely high-quality image display device represented by this type can be provided. In addition, it can be suitably used as automotive interior parts such as instrument panels and glove boxes, automotive exterior parts such as weather strips, weak electrical parts, anti-vibration materials for electrical appliances, other industrial parts, building materials, sports equipment, etc. .

Claims (14)

(A) an ethylene / α-olefin copolymer rubber, and (B) a mixture containing a first olefin thermoplastic resin having a melt tension of 3.0 cN or more at 210 ° C. and a take-off speed of 2.0 m / min,
(C) A precursor is obtained by dynamically heat-treating in the presence of a crosslinking agent, and the obtained precursor is
(D) A method for producing a thermoplastic elastomer composition comprising adding a second olefin-based thermoplastic resin having a melt tension of 3.0 cN or higher at 210 ° C. and a take-off speed of 2.0 m / min.   A thermoplastic elastomer composition produced by the method for producing a thermoplastic elastomer composition according to claim 1.   The thermoplastic elastomer composition according to claim 2, wherein the compression set is 60% or less measured under conditions of 70 ° C and 22 hours in accordance with JIS K6262.   A foam obtained by foaming the thermoplastic elastomer composition according to claim 2.   The manufacturing method of the foam which foams the thermoplastic-elastomer composition of Claim 2 or 3 with a supercritical fluid. A step of blending 0.01 to 20 parts by mass of a chemical foaming agent with respect to 100 parts by mass of the thermoplastic elastomer composition according to claim 2 or 3 to obtain a chemical foaming agent mixed raw material;
And foaming the obtained chemical foaming agent mixed raw material.   The method for producing a foam according to claim 5 or 6, further comprising a step of irradiating with an electron beam. A sheet-like base material comprising the foam according to claim 4;
A laminated sheet comprising: an adhesive layer made of an adhesive and having an adhesive surface, disposed on at least one surface of the substrate.   The laminated sheet according to claim 8, wherein the pressure-sensitive adhesive is at least one selected from the group consisting of an olefin polymer, a styrene polymer, an acrylic polymer, and a polyester polymer.   The laminated sheet according to claim 8 or 9, further comprising a release sheet disposed on the adhesive surface. Extruding the thermoplastic elastomer composition according to claim 2 or 3 to obtain a sheet-like base material comprising a foam obtained by foaming the thermoplastic elastomer composition;
Disposing an adhesive layer made of an adhesive and having an adhesive surface on at least one surface of the base material. Extruding the thermoplastic elastomer composition according to claim 2 or 3, and an adhesive,
While molding a sheet-like substrate made of a foam obtained by foaming the thermoplastic elastomer composition,
The manufacturing method of a lamination sheet including arrange | positioning the adhesion layer which consists of the said adhesives and has an adhesion surface on the at least 1 surface of the said base material.   The adhesion method of a lamination sheet including sticking the adhesive surface of the adhesion layer with which the lamination sheet as described in any one of Claims 8-10 is equipped to the surface of a to-be-adhered body. An image display panel having a viewing surface;
A transparent front plate that protects the image display panel disposed at a predetermined interval on the viewing surface;
The laminated sheet according to any one of claims 8 to 10, which is disposed between the image display panel and the transparent front plate,
An image display device comprising: the image display panel, the transparent front plate, and a case for storing the laminated sheet.

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