Thermally decomposable sheet, thermally decomposable sheet with peeling liner, laminate, joined body, method for manufacturing joined body, and method for disassembling joined body

Abstract

To provide a thermally decomposable sheet which is excellent in adhesive force and thermal decomposition property, and a laminate using the thermally decomposable sheet, a joined body excellent in thermal decomposition property, a method for manufacturing a joined body, and a method for disassembling a joined body.SOLUTION: A thermally decomposable sheet includes a thermally decomposable layer, wherein the thermally decomposable layer has an elastic modulus E'25 at 25°C of 106 Pa or more and 1010 Pa or less, and elastic modulus E'110 at 110°C of 107 Pa or less, and the elastic modulus E'25 at 25°C is 100 times or more the elastic modulus E'110 at 110°C.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a thermally disintegrable sheet, a thermally disintegrable sheet with a release liner, a laminate, a bonded body, a method for producing a bonded body, and a method for disassembling a bonded body. [Background technology]

[0002] Adhesives are used to join members made of various materials such as resin, rubber, metal, glass, ceramics, and paper. In recent years, research has been conducted into easily dismantlable adhesives that have sufficient adhesive strength according to the intended use and the ability to reduce adhesive strength at any time to allow for easy peeling (dismantling). Demand for such easily dismantlable adhesives is increasing for applications such as the separate collection of bonding materials used to join components made of different materials, the repair and replacement of components, and improving productivity through temporary bonding in the manufacturing process.

[0003] As dismantling means, for example, methods using stimuli such as heating, voltage application, light irradiation, and immersion in chemical solutions are being considered. Dismantling means using heat include, for example, thermal decomposition of resins and additives contained in adhesives, and expansion of additives, and as expansion agents, resin microcapsules containing liquid low-boiling point hydrocarbons and inorganic expansion agents such as expanded graphite are used.

[0004] For example, Patent Document 1 describes a hot melt adhesive that uses a thermoplastic epoxy resin with a specific formulation and can be attached and fixed to an adherend at relatively low temperatures, and can be bonded by heating to 150°C or higher.It also has high shear adhesive strength and, because it is thermoplastic, can be made recyclable by reheating. Furthermore, Patent Document 2 describes an easily dismantled adhesive sheet having an adhesive layer containing an inorganic expanding agent and a resin, with the adhesive strength of the adhesive layer controlled within a specific range, which provides excellent adhesiveness and holding power, and also provides excellent adhesive strength for firmly adhering adherends, as well as dismantlability that allows the bonded body to be easily dismantled when desired. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-126942 [Patent Document 2] International Publication No. 2023 / 176800 Summary of the Invention [Problem to be solved by the invention]

[0006] However, since the hot melt adhesive described in Patent Document 1 has a high modulus of elasticity at 120°C, the dismantling properties of a bonded body using this hot melt adhesive are insufficient, resulting in poor workability. Furthermore, the easily dismantlable adhesive sheet described in Patent Document 2 is adhesive, which makes it difficult to adjust the attachment position when attaching the adherends, resulting in poor workability.

[0007] The present invention has been made in view of the above-mentioned circumstances, and aims to provide a thermally disintegrable sheet and a thermally disintegrable sheet with release liners that are excellent in adhesive strength and thermal disintegrability. It is also an object of the present invention to provide a laminate using the thermally disintegrable sheet, a bonded body that is excellent in thermal disintegrability, a method for manufacturing a bonded body, and a method for disassembling a bonded body. [Means for solving the problem]

[0008] The present inventors have conducted extensive research to solve the above problems, and as a result have found that a thermally disintegrable sheet having an elastic modulus controlled within a specific range at a specific temperature can provide a bonded article that exhibits excellent adhesive strength for firmly bonding adherends and thermal disintegrability that allows easy disassembly at a desired temperature, thereby completing the present invention.

[0009] The means for solving the above problems are as follows. [1] A thermally disintegrable sheet comprising a thermally disintegrable layer, The thermally disintegratable layer is Elastic modulus E' at 25°C 25 is 10 6 Pa or more 1010 Pa or less, Elastic modulus E' at 110℃ 110 is 10 7 Pa or less, The elastic modulus E' at 25°C 25 The elastic modulus E' at 110°C 110 A thermally disintegrable sheet that is 100 times or more stronger than the original. [2] The thermally disintegrable sheet according to [1], wherein the thermally disintegrable layer has a disintegration temperature of 80°C to 130°C. [3] The thermally disintegrable layer has a shear adhesive strength F 25 and shear adhesive strength F at 110°C 110 and satisfy the following formula (1): F 110 / F 25 <0.5 Equation (1) [4] The thermally disintegrable sheet according to [1], wherein the thermally disintegrable layer contains a resin. [5] The thermally disintegratable sheet according to [4], wherein the resin comprises at least one selected from polyamide resin, acrylic rubber, and epoxy resin. [6] The thermally disintegrable sheet according to [4], wherein the resin comprises an epoxy-modified resin. [7] A thermally disintegrable sheet with a release liner, in which at least one surface of the thermally disintegrable layer in the thermally disintegrable sheet according to any one of [1] to [6] is protected by a release liner. [8] A laminate in which the thermally disintegrable sheet according to any one of [1] to [6] is laminated on a resin material. [9] A bonded body obtained by bonding the thermally disintegrable sheet according to any one of [1] to [6] and a resin material.

[10] the resin material is a first member, The joined body according to [9], wherein the first member and the second member are joined using the thermally disintegrable sheet.

[11] The bonded body according to [9], wherein the resin material includes a thermosetting resin.

[12] A method for producing a bonded body using the thermally disintegrable sheet according to any one of [1] to [6].

[13] a lamination step of laminating the thermally disintegratable sheet and a resin material; a fusion step of fusing the thermally disintegratable layer and the resin material, A method for producing the bonded body according to

[12] .

[14] a lamination step of laminating the thermally disintegrable sheet and a substrate; an impregnation step of impregnating the substrate with a resin composition; a curing step of curing the resin composition to form a resin material; Equipped with A method for producing the bonded body according to

[12] .

[15] A method for dismantling a bonded structure including a thermally dismantlable layer, comprising: The thermally disintegrable layer has an elastic modulus E' at 25°C 25 is 10 6 Pa or more 10 10 Pa or less, Elastic modulus E' at 110℃ 110 is 10 7 Pa or less, The elastic modulus E' at 25°C 25 The elastic modulus E' at 110°C 110 is more than 100 times A method for disassembling a bonded body, comprising the step of heating at least a part of the bonded body to destroy the thermally disintegrable layer. [Effects of the Invention]

[0010] According to the present invention, it is possible to obtain a thermally disintegrable sheet and a thermally disintegrable sheet with a release liner that are excellent in adhesive strength and thermal disintegration. Furthermore, a bonded body bonded with the thermally disintegrable sheet of the present invention has excellent thermal disintegration properties, being easily disintegrated at a desired temperature. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic cross-sectional view showing a thermally disintegrable sheet according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view showing a thermally disintegrable sheet according to another embodiment of the present invention. [Figure 3] FIG. 3 is a schematic cross-sectional view showing a bonded body bonded by a thermally disintegrable sheet according to an embodiment of the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional view for explaining a bonded structure used in the evaluation of shear adhesive strength in the examples. [Figure 5] FIG. 5 is a schematic cross-sectional view for explaining a bonded structure used in the evaluation of shear adhesive strength in the examples. [Figure 6] FIG. 6 is a schematic cross-sectional view for explaining a bonded structure used in the evaluation of shear adhesive strength in the examples. [Figure 7] FIG. 7 is a schematic cross-sectional view for explaining a bonded structure used in the evaluation of shear adhesive strength in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention will be described in detail below with reference to the accompanying drawings, but the present invention is not limited to the following embodiments and can be modified as desired without departing from the spirit of the present invention. Furthermore, the symbol "to" indicating a numerical range is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0013] In this specification, "adhesion" means that two surfaces are temporarily joined together by external pressure (microscopic pressure) based on the cohesive force of the chemical structure of the composition, and can be peeled off if necessary.

[0014] "Adhesion" refers to the composition undergoing a chemical reaction (curing) to produce a hardened product that can firmly bond two surfaces together. In this specification, unless otherwise specified, the term "major component" refers to a component that is contained in an amount of more than 50% by mass. In this specification, percentages based on mass are synonymous with percentages based on weight.

[0015] [Thermal decomposition sheet] The thermally disintegrable layer in the thermally disintegrable sheet according to an embodiment of the present invention has an elastic modulus E' at 25°C. 25 is 10 6 Pa or more 10 10 The elastic modulus E' at 110°C is less than or equal to Pa. 110 is 10 7 Pa or less, and the elastic modulus E' at 25°C 25 The elastic modulus E' at 110°C 110 This is more than 100 times the amount. The thermally disintegrable sheet according to an embodiment of the present invention has an elastic modulus E' at 25°C. 25 to 10 6 Pa or more 10 10 By setting the modulus of elasticity E' at 110°C or less, the adhesiveness is low at room temperature, and the adhesive does not stick to the adherend when placed on it, making it easy to adjust the position, and improving work efficiency when producing a bonded body. 110 to 10 7 Pa or less, E' 25 E' 110 By making the modulus of elasticity 100 times or more, the modulus of elasticity decreases at 110°C, and excellent dismantling properties are exhibited.

[0016] Fig. 1 is a schematic cross-sectional view showing a thermally disintegrable sheet according to an embodiment of the present invention. As shown in Fig. 1, the thermally disintegrable sheet 100 according to this embodiment includes a thermally disintegrable layer, and may consist of only a thermally disintegrable layer 11. Although Fig. 1 shows a thermally disintegrable layer having a single-layer structure, the thermally disintegrable layer may have a multi-layer structure of two or more layers.

[0017] The thermally disintegrable sheet of this embodiment may include a supporting substrate 12 as shown in Fig. 2. The thermally disintegrable sheet of this embodiment may also include layers other than the thermally disintegrable layer 11. There are no particular restrictions on the layers other than the thermally disintegrable layer 11, and known layers can be used depending on the application of the thermally disintegrable sheet, the material of the adherend, etc.

[0018] Fig. 3 is a schematic cross-sectional view showing one embodiment of a bonded structure bonded by a thermally disintegrable sheet according to an embodiment of the present invention. The bonded structure 200 shown in Fig. 3 is a bonded structure in which a first member 14 and a second member 15 are bonded via a thermally disintegrable layer 11 as an adherend.

[0019] As described above, the thermally disintegrable sheet according to the embodiment of the present invention preferably includes a thermally disintegrable layer, but may consist of only a thermally disintegrable layer. The thermally disintegrable sheet according to the present embodiment may be a sheet with a supporting substrate in a form in which the thermally disintegrable layer is provided on one side (FIG. 2) or both sides of a sheet-like substrate (supporting substrate), or may be a substrate-less thermally disintegrable sheet in a form in which at least one surface of the thermally disintegrable layer is supported by a release liner. In other words, the thermally disintegrable sheet according to an embodiment of the present invention can be a thermally disintegrable sheet with a release liner (hereinafter sometimes simply referred to as a thermally disintegrable sheet) in which at least one surface of the thermally disintegrable layer in the thermally disintegrable sheet is protected by a release liner.

[0020] The thermally disintegrable layer is typically formed continuously, but is not limited to this form, and may be formed in a regular or random pattern such as dots or stripes. The thermally disintegrable layer of this embodiment may be in the form of a roll or sheets. Alternatively, it may be a thermally disintegrable sheet processed into various shapes.

[0021] <Thermodegradable layer> In the thermally disintegrable sheet according to the embodiment of the present invention, the thermally disintegrable layer is preferably a sheet-like layer containing a resin. The thermally disintegrable layer can be formed into a sheet from a resin composition. The resin composition contains a resin and can be formed into a sheet to form a thermally disintegratable layer. The resin composition may further contain a crosslinking agent.

[0022] The thermally disintegrable sheet according to an embodiment of the present invention can be placed on an adherend and then cured to form a strong bond to the adherend, and two or more adherends can be bonded together via the thermally disintegrable sheet (which may be a thermally disintegrable layer) to form a bonded body. The thermally disintegrable layer is preferably cured by at least one of a polymerization reaction and a crosslinking reaction of the resin contained in the thermally disintegrable layer. That is, the resin layer according to the embodiment of the present invention is preferably cured by at least one of a polymerization reaction and a crosslinking reaction after being placed on an adherend.

[0023] (resin) The resin contained in the thermally disintegrable layer according to the embodiment of the present invention is not particularly limited, and may be at least one type of resin, and preferably two or more types of resin. Examples of resins contained in the thermally disintegrable layer according to the embodiment of the present invention include thermoplastic resins and thermosetting resins, and from the viewpoint of disintegrability when heated, it is preferable that the thermally disintegrable layer contains a thermoplastic resin.

[0024] Examples of thermosetting resins include epoxy resins, phenolic resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, thermosetting polyimide resins, melamine-based resins, and alkyd-based resins. Among these, epoxy resins are preferably used.

[0025] Examples of epoxy resins include bisphenol A, bisphenol F, bisphenol S, brominated bisphenol A, hydrogenated bisphenol A, bisphenol AF, biphenyl, naphthalene, fluorene, phenol novolac, cresol novolac, orthocresol novolac, trishydroxyphenylmethane, tetraphenylolethane, hydantoin, trisglycidyl isocyanurate, and glycidylamine epoxy resins. Among these, bisphenol A epoxy resins are more preferably used.

[0026] Furthermore, as the thermosetting resin, a thermoplastic resin having a thermosetting functional group can also be used. Examples of the thermosetting functional group include an acrylate group, an epoxy group, an oxetane group, an isocyanate group, and a silanol group. Examples of the thermoplastic resin having a thermosetting functional group include a thermosetting functional group-containing resin. Examples of the thermosetting functional group-containing resin include an acrylic-modified resin, a polyurethane-modified resin, an epoxy-modified resin, a phenol-modified resin, a polyether-modified resin, and a silicone-modified resin. From the viewpoints of adhesion to an adherend and storage stability before use, an epoxy-modified resin is preferred.

[0027] More specifically, examples of the thermosetting functional group-containing resin include polyurethane-modified acrylic resin, acrylic-modified polyurethane resin, epoxy-modified acrylic resin, epoxy-modified polyurethane resin, o-cresol-modified resin, phenol-modified acrylic resin, phenol-modified polyurethane resin, phenol-modified epoxy resin, polyether-modified acrylate resin, and silicone-modified acrylate resin. The resin contained in the thermally disintegrable layer according to the embodiment of the present invention preferably contains an epoxy-modified resin from the viewpoints of adhesion to an adherend and storage stability before use.

[0028] Examples of the acrylic resin in the thermosetting functional group-containing acrylic resin include those containing a monomer unit derived from a (meth)acrylic acid ester. In the case of a thermoplastic resin having a thermosetting functional group, a curing agent is selected depending on the type of the thermosetting functional group.

[0029] Furthermore, examples of thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, styrene rubber (e.g., styrene-butadiene rubber, styrene-isoprene rubber, styrene-ethylene-propylene-styrene rubber, styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, styrene-ethylene-propylene block copolymer, etc.), chloroprene rubber, ethylene-propylene rubber, acrylic rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resins such as polyamide 6 and polyamide 6,6, phenoxy resin, thermoplastic acrylic resin, saturated polyester resins such as PET and PBT, polyamide-imide resin, fluororesin, etc. The thermoplastic resins may be used singly or in combination of two or more.

[0030] The thermoplastic acrylic resin is preferably a polymer containing a monomer unit derived from a (meth)acrylic acid ester as the most abundant monomer unit by mass. Examples of (meth)acrylic acid esters include (meth)acrylic acid alkyl esters, (meth)acrylic acid cycloalkyl esters, and (meth)acrylic acid aryl esters. The acrylic resin may also contain a monomer unit derived from another component copolymerizable with the (meth)acrylic acid ester. Examples of the other component include functional group-containing monomers such as carboxyl group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphate group-containing monomers, acrylamides, and acrylonitriles, as well as various polyfunctional monomers.

[0031] The resin contained in the thermally disintegratable layer according to the embodiment of the present invention preferably contains at least one selected from polyamide resin, acrylic rubber, and epoxy resin, since it has thermoplastic properties and strong adhesive properties to the interface with the adherend.

[0032] The polyamide resin is not particularly limited as long as it has an amide bond as a repeating unit in the main chain, and examples thereof include polymers of aliphatic or aromatic diamines and aliphatic or aromatic dicarboxylic acids, ring-opening polymers of cyclic lactams, etc. These may be used alone or in combination of two or more.

[0033] Examples of acrylic rubber include NBR (nitrile butadiene rubber), carboxy-terminated butadiene-acrylonitrile copolymer rubber (CTBN), copolymers of acrylic esters and 2-chloroethyl vinyl ether, copolymers of acrylic esters and acrylonitrile, and copolymers of acrylic esters and acrylic acid. The acrylic rubbers can be used alone or in combination of two or more kinds.

[0034] Commercially available resins may be used. For example, commercially available polyamide resins include "Platamid M1276" (manufactured by Arkema) and "Ultramid 1C" (manufactured by BASF), commercially available epoxy resins include "jER1256," "jER1256B40," and "jER872" (manufactured by Mitsubishi Chemical Corporation), and acrylic rubbers include "HyPoxRK84L" and "HyPoxRA820" (manufactured by HUNTSMAN).

[0035] The resins may be used singly or in combination of two or more. From the viewpoint of improving the dismantling property during thermal dismantling, the resin is preferably a thermoplastic resin, and more preferably a polyamide resin, a phenoxy resin, or an acrylic rubber. The resin preferably contains an epoxy-modified resin. By including the epoxy-modified resin in the resin, a strong bond with the adherend interface can be achieved during bonding.

[0036] The blending ratio of the resin is, for example, 50 parts by mass or more, preferably 80 parts by mass or more, more preferably 90 parts by mass or more, and for example, 100 parts by mass or less, preferably 99 parts by mass or less, more preferably 98 parts by mass or less, relative to 100 parts by mass of all resin components in the thermally disintegratable composition.

[0037] (Crosslinking agent) Furthermore, when a resin having a crosslinked structure is blended into the thermally disintegrable composition, a crosslinking agent can be blended when preparing the thermally disintegrable composition, which makes it easier to adjust the elastic modulus E' of the thermally disintegrable layer to a specific range.

[0038] Examples of the crosslinking agent include isocyanate-based crosslinking agents, aziridine-based crosslinking agents, epoxy-based crosslinking agents, silane-based crosslinking agents, metal chelate-based crosslinking agents, and amide-based compounds, and isocyanate-based crosslinking agents are preferred.

[0039] Examples of the isocyanate crosslinking agent include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate; aromatic diisocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate and polymethylene polyphenyl isocyanate; trimethylolpropane / tolylene diisocyanate trimer adduct (e.g., "D-101E" (manufactured by Mitsui Chemicals, Inc.)), trimethylolpropane / hexamethylene diisocyanate trimer adduct (e.g., "Coronate HL" (manufactured by Tosoh Corporation)), and isocyanurate of hexamethylene diisocyanate (e.g., "Coro"). isocyanate adducts such as "Takenate HX" (manufactured by Tosoh Corporation); trimethylolpropane adducts of xylylene diisocyanate (for example, "Takenate D110N" (manufactured by Mitsui Chemicals, Inc.)), trimethylolpropane adducts of xylylene diisocyanate (for example, "Takenate D120N" (manufactured by Mitsui Chemicals, Inc.)), trimethylolpropane adducts of isophorone diisocyanate (for example, "Takenate D120N" (manufactured by Mitsui Chemicals, Inc.)), trimethylolpropane adducts of hexamethylene diisocyanate (for example, "Takenate D160N" (manufactured by Mitsui Chemicals, Inc.)); polyether polyisocyanates, polyester polyisocyanates, and adducts of these with various polyols; and polyisocyanates multifunctionalized with isocyanurate bonds, biuret bonds, allophanate bonds, etc.

[0040] As the epoxy-based crosslinking agent, a multifunctional epoxy compound having two or more epoxy groups in one molecule can be used. Examples of the epoxy-based crosslinking agent include N,N,N',N'-tetraglycidyl-m-xylylenediamine, diglycidylaniline, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and polypropylene glycol. Examples of epoxy resins include diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris(2-hydroxyethyl)isocyanurate, resorcinol diglycidyl ether, bisphenol-S-diglycidyl ether, and epoxy resins having two or more epoxy groups in the molecule. Commercially available epoxy crosslinking agents include diglycidylaniline, N,N,N',N'-tetraglycidyl-m-xylylenediamine ("TETRAD-X" (Mitsubishi Gas Chemical Company, Inc.)), and 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane ("TETRAD-C" (Mitsubishi Gas Chemical Company, Inc.)). These compounds may be used alone or in combination of two or more.

[0041] Examples of silane crosslinking agents include epoxy group-containing silane coupling agents such as 3-glycidoxypropyltrimethoxysilane ("KBM403" (Shin-Etsu Chemical Co., Ltd.)), 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; amino group-containing silane coupling agents such as 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, and N-phenyl-γ-aminopropyltrimethoxysilane; (meth)acrylic group-containing silane coupling agents such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltriethoxysilane; and isocyanate group-containing silane coupling agents such as 3-isocyanatepropyltriethoxysilane.

[0042] Examples of amide compounds include dicyandiamide and polyamide, and preferably dicyandiamide (for example, "Omicure DDA-50" (manufactured by HUNTSMAN)).

[0043] The blending ratio of the crosslinking agent relative to 100 parts by mass of the first resin is, for example, 0.1 part by mass or more, or preferably 0.3 part by mass or more, and for example, 20 parts by mass or less, or preferably 15 parts by mass or less, thereby adjusting the elastic modulus E' of the thermally disintegratable layer.

[0044] (hardening agent) A curing agent can also be blended into the thermally disintegrable composition, which makes it easier to adjust the elastic modulus E' of the thermally disintegrable layer to a specific range.

[0045] The curing agent is a component that reacts with the resin to cure the thermally disintegrable layer when the thermally disintegrable composition contains the resin. The curing agent may be appropriately selected from curing agents that can cure the resin depending on the type and composition of the resin used.

[0046] For example, when the resin contains an epoxy resin, the curing agent is preferably an epoxy resin curing agent. The epoxy resin curing agent is preferably a latent curing agent, which can achieve stronger adhesion to the interface of the adherend by reacting with the adherend when the epoxy resin is joined. The epoxy resin curing agent may be a heat-curing or photo-curing curing agent, preferably a heat-curing or photo-curing latent curing agent. The epoxy resin curing agent may be a heat-curing curing agent, preferably a heat-curing latent curing agent.

[0047] As the thermosetting epoxy curing agent, known curing agents used for curing epoxy resins can be used, and examples thereof include urea-based compounds, amine-based compounds, acid anhydride-based compounds, amide-based compounds, hydrazide-based curing agents, imidazole-based curing agents, imidazoline-based compounds, triphenylphosphine-based compounds, thermal base generators, trihalogenborane-based compounds, carboxylic acid-based compounds, phenolic resin-based compounds, polymercaptan-based curing agents, etc. The epoxy curing agents can be used alone, or two or more types can be used in combination.

[0048] Specific examples of epoxy resin curing agents include dicyandiamide, 3-methyl-1,2,3,6-tetrahydrophthalic anhydride, 4-methyl-1,2,3,6-tetrahydrophthalic anhydride, diethylenetriamine, and triethylenetetramine.

[0049] The blending ratio of the epoxy resin curing agent can be appropriately selected depending on the type of curing agent. When dicyandiamide is used as the curing agent, the blending ratio of the thermal decomposable agent composition is, for example, 0.5% by mass or more, preferably 1% by mass or more, and, for example, 100% by mass or less, preferably 5% by mass or less. If the blending ratio of the curing agent is within the above range, a strong bond can be formed with the interface of the adherend during bonding.

[0050] As imidazole compounds, for example, various grades of the "Curesol" series are commercially available from Shikoku Chemical Industry Co., Ltd., and among them, for example, "Curesol 2MZA-PW" (manufactured by Shikoku Chemical Industry Co., Ltd.), "Curesol 2PHZ-PW" (manufactured by Shikoku Chemical Industry Co., Ltd.), "Curesol 2MA-OK" (manufactured by Shikoku Chemical Industry Co., Ltd.) and the like can be suitably used. As urea compounds, for example, "Omicure U-24M" (manufactured by HUNTSMAN), "Omicure U-52" (manufactured by HUNTSMAN), "3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU)" (manufactured by Hodogaya Chemical Co., Ltd.) and the like can be mentioned.

[0051] (filler) The thermally disintegrable composition (which may be the thermally disintegrable layer) may contain a filler. The type and amount of the filler to be added are not particularly limited. The thermally disintegrable composition (which may be the thermally disintegrable layer) contains a filler, which makes it possible to adjust the shear adhesive strength and elastic modulus E' of the thermally disintegrable layer.

[0052] The proportion of the filler in the thermally disintegratable composition (which may be the thermally disintegratable layer) is not particularly limited, and is preferably 0.1 to 50 parts by mass, 0.5 to 40 parts by mass, more preferably 1 to 30 parts by mass, more preferably 5 to 21 parts by mass, and more preferably 10 to 20 parts by mass, relative to 100 parts by mass of the thermally disintegratable composition. If the proportion is less than 0.1 part by mass, a sufficient improvement in the elastic modulus cannot be obtained. If the content exceeds 50 parts by mass, it becomes difficult to form the thermally disintegratable layer.

[0053] The filler is not particularly limited and may be in the form of fibers, bundles, plates, layers, needles, spikes, irregular shapes or other non-particulate shapes, fine particles, secondary particles (aggregates) of fine particles, solid particles, hollow particles, or organic or inorganic fine particles, without any limitation.

[0054] ((Inorganic fine particles)) Examples of inorganic fine particles that can be blended into the thermally disintegratable composition of the present invention include metal oxides such as silica, alumina, zirconia, and titania; metal salts such as aluminum borate and aluminum hydroxide; minerals such as mica; and inorganic fine particles having a hollow structure such as hollow nanosilica. These can be used alone or in combination of two or more.

[0055] ((Organic fine particles)) Examples of organic fine particles that can be incorporated into the thermally disintegratable composition of the present invention include fine particles composed of polymers such as styrene resins, acrylic resins, silicone resins, acrylic-styrene resins, vinyl chloride resins, vinylidene chloride resins, amide resins, urethane resins, phenol resins, styrene-conjugated diene resins, acrylic-conjugated diene resins, olefin resins, and fluorine-based resins, as well as crosslinked products of these polymers, and fine particles composed of these crosslinked polymers to have a hollow structure. These can be used alone or in combination of two or more types.

[0056] The inorganic fine particles may be surface-treated to improve dispersibility in the thermally decomposable composition. Any known or commonly used surface treatment agent can be used without limitation. Examples of such surface treatment agents include silane coupling agents, titanium coupling agents, organic acids, polyols, and silicones. Silane coupling agents are preferred. Examples of silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, dimethylvinylmethoxysilane, dimethylvinylethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, vinyltris(2-methoxy)silane, vinyltriacetoxysilane, 2-methacryloxyethyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, triethoxyphenylsilane, trimethoxyphenylsilane, dimethoxydiphenylsilane, methyldiethoxyphenylsilane, and dimethoxymethylphenylsilane.

[0057] The surface of the filler is not particularly limited. For example, the filler may be untreated or may be surface-treated, but it is preferred that the surface of the filler is untreated or that the functional group on the surface of the filler is at least one group selected from the group consisting of a silanol group, a hydroxyl group, an amino group, a mercapto group, a carboxyl group, an isocyanate group, and an epoxy group.

[0058] Examples of the filler include silica particles such as fumed silica, colloidal silica, and precipitated silica, and silica-based fillers such as silica gel, silica aerogel, quartz glass, and glass fiber. Among these, fumed silica and colloidal silica are preferred from the viewpoint of being easily mixed into the thermally disintegratable composition.

[0059] As the fumed silica, a general commercially available product can be used, for example, hydrophobic fumed silica manufactured by Nippon Aerosil Co., Ltd., specifically, products under the trade names "AEROSIL (registered trademark) RX series" (RX50, RX200, RX300, etc.) and "AEROSIL (registered trademark) RY series" (RY50, RY200, RY200S, etc.) manufactured by Nippon Aerosil Co., Ltd. Furthermore, examples of hydrophilic fumed silica include "M5 Cab-o-sil" (manufactured by CABOT).

[0060] The thermally disintegratable composition may contain appropriate additives depending on the application of the thermally disintegratable sheet, such as leveling agents, crosslinking aids, plasticizers, softeners, antistatic agents, ultraviolet absorbers, fillers, antioxidants, antioxidants, light stabilizers, colorants (pigments, dyes, etc.), foaming agents, etc. As for such various additives, conventionally known ones can be used in the usual manner, and detailed description thereof will be omitted since they do not particularly characterize the present invention.

[0061] The method for preparing the thermally disintegratable composition is not particularly limited, and for example, a liquid composition containing each component and, if necessary, a solvent is prepared, and the composition can be obtained using a planetary centrifugal mixer. The thermally disintegrable layer may be formed into a sheet by applying the thermally disintegrable composition onto the substrate, drying it, and removing the solvent.

[0062] When forming a thermally disintegrable layer by applying a thermally disintegrable composition, the application can be carried out using a conventional coater such as a gravure roll coater, reverse roll coater, kiss roll coater, dip roll coater, bar coater, knife coater, spray coater, etc. In the thermally disintegrable sheet having a supporting substrate described below, the method of providing a thermally disintegrable layer on the supporting substrate may be a direct method in which the thermally disintegrable composition is directly applied to the supporting substrate to form a thermally disintegrable layer, or a transfer method in which a thermally disintegrable layer formed on a release surface is transferred to the substrate.

[0063] As another method for preparing the thermally disintegrable composition, the composition can be obtained by heating and kneading the components using a kneader such as a twin-screw kneader, a kneader, etc. The thermally disintegrable composition may also be obtained by compressing and stretching the composition by calendar molding, extrusion molding, press molding, or the like to form the thermally disintegrable layer into a sheet shape.

[0064] The thickness of the thermally disintegratable layer is not particularly limited and is, for example, 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and for example, 3000 μm or less, preferably 1000 μm or less, more preferably 500 μm or less.

[0065] (Elastic modulus E' of thermally degradable layer) The thermally disintegratable layer according to the embodiment of the present invention has an elastic modulus E' at 25°C. 25 is 10 6 Pa or more 10 10 Pa or less, Elastic modulus E' at 110°C 110 is 10 7 Pa or less, The elastic modulus E' at 25°C 25 The elastic modulus E' at 110°C 110 This is more than 100 times the amount.

[0066] The thermally disintegratable layer according to the embodiment of the present invention has an elastic modulus E' at 25°C from the viewpoint of ease of handling when placed on an adherend. 25 is 10 6 Pa or more, and 7 In addition, from the viewpoint of conformability to the adherend and the toughness and brittleness of the thermally disintegratable layer, the elastic modulus E' at 25°C is preferably 1. 25 is 10 10 It is preferable that the pressure is 0.01 Pa or less.

[0067] The thermally disintegratable layer according to the embodiment of the present invention has an elastic modulus E' at 110°C from the viewpoint of disintegratability when heated. 110 is 10 7 Pa or less, and 6 It is more preferable that the viscosity is 0.05 Pa or less.

[0068] The thermally disintegrable layer according to the embodiment of the present invention has a strength when used at room temperature and a disintegrability when heated, and has an E' 25 But E' 110 It is preferably 100 times or more, and more preferably 1000 times or more.

[0069] The elastic modulus E' of the thermally disintegrable layer is dynamic viscoelasticity measured by a viscoelasticity measuring device. Specifically, for example, the produced thermally disintegrable layer is cut into a piece 10 mm wide x 50 mm long, and the dynamic viscoelasticity can be measured using a rheometer (RSA G2, manufactured by TA Instruments) at a frequency of 1 Hz, a heating rate of 5°C / min, and a measurement temperature of -40 to 200°C. In this manner, the dynamic viscoelasticity of the thermally disintegrable layer at each temperature is measured, and this is taken as the elastic modulus E'. More specifically, it can be measured by the method described in the Examples.

[0070] (Shear adhesive strength of thermally degradable layer) A thermally disintegrable sheet exhibiting high shear adhesive strength exhibits strong resistance to forces that tend to displace the adhesive interface of the thermally disintegrable layer (i.e., shear forces), and therefore has excellent adherend retention performance. From the viewpoint of exhibiting higher retention performance, the shear adhesive strength F of the thermally disintegrable layer in the thermally disintegrable sheet at 25°C is 25 is preferably 5 MPa or more, more preferably 7 MPa or more. In some embodiments, there is no particular upper limit to the shear adhesive strength, and generally, the higher the shear adhesive strength, the better. On the other hand, the shear adhesive strength F of the thermally disintegratable layer in the thermally disintegratable sheet at 25°C 25 is higher than the strength of the adherend, and when force is applied in the shear direction, the adherend may break. When such a form of failure is observed, it can be judged that the adhesive has sufficient adhesiveness even if the shear adhesive strength is lower than the above value. In the above-mentioned embodiment, the shear adhesive strength F of the thermally disintegrable layer at 25°C 25 For example, the pressure may be 20 MPa or less, 15 MPa or less, or 10 MPa or less.

[0071] In this way, the thermally disintegrable layer exerts a high shear adhesive strength, and thus it is possible to firmly bond to an adherend, or to bond two or more adherends via the thermally disintegrable sheet.

[0072] The thermally disintegratable layer according to the embodiment of the present invention preferably further has the following properties. The thermally disintegratable layer according to the embodiment of the present invention has a shear adhesive strength F 25 and shear adhesive strength F at 110°C 110 It is preferable that the following formula (1) is satisfied. F 110 / F 25 <0.5 Equation (1)

[0073] Shear adhesive strength F of thermally decomposable layer at 25°C 25 and shear adhesive strength F at 110°C 110 Shear adhesive strength ratio F 110 / F 25However, by satisfying the above formula (1), the bonded body has sufficient strength in the temperature range in which it is actually used, making it difficult to break, and since the strength decreases at high temperatures (110°C), it can be disassembled with a small force. 110 / F 25 From the viewpoint of the actual use temperature and strength at high temperatures (disassembly), is preferably 0.5 or less, and more preferably 0.4 or less.

[0074] In terms of thermal disintegration, the shear adhesive strength F at 110°C of the thermally disintegrable layer according to an embodiment of the present invention 110 However, it is preferably 10 MPa or less, and more preferably 8 MPa or less.

[0075] Shear adhesive strength F at 25°C in the thermally disintegrable layer according to an embodiment of the present invention 25 and shear adhesive strength F at 110°C 110 can be measured in accordance with JIS K 6850, specifically by the method described in the Examples.

[0076] (Decomposition temperature of thermally decomposable layer) The thermally disintegrable layer according to the embodiment of the present invention preferably has a disintegration temperature of 80°C to 130°C. Here, the disassembly temperature of the thermally disintegrable layer refers to the temperature at which the thermally disintegrable layer is disassembled when heated after being bonded to an adherend. The disassembly temperature is the temperature at which the shear adhesive strength of the thermally disintegrable layer at the disassembly temperature is 10 MPa or less, or the shear adhesive strength F at 25 ° C. 25 The temperature at which the temperature is less than half of the normal value.

[0077] If the thermally disintegratable layer has a disintegration temperature of 80°C or higher, sufficient adhesiveness can be maintained within the range of general practical temperatures, for example, outdoors in summer or inside a car. Furthermore, if the disassembly temperature of the thermally disintegrable layer is 130°C or lower, it has the effect of reducing the thermal energy applied to the adherends and the thermally disintegrable layer. Furthermore, if the adherends are organic (such as engineering plastics), a disassembly temperature of 130°C or lower will prevent the adherends from melting due to heat, allowing the two or more adherends to be separated without being damaged. In this case, the bonded structure can be disassembled at a temperature lower than the melting temperature of the adherends, reducing the thermal energy required for disassembly compared to melting the adherends to disassemble them.

[0078] The lower limit of the decomposition temperature of the thermally decomposable layer is more preferably 60°C or higher, and even more preferably 80°C or higher. The upper limit of the decomposition temperature of the thermally decomposable layer is more preferably 170°C or lower, even more preferably 150°C or lower, and particularly preferably 130°C or lower.

[0079] The decomposition temperature of the thermally decomposable layer can be adjusted by blending the resin used in the thermally decomposable layer and additives such as a crosslinking agent and a curing agent.

[0080] (Surface tension of thermally disintegrable layer) The thermally disintegratable layer according to the embodiment of the present invention preferably has a surface tension of 38 mN / m or more.

[0081] Here, the surface tension of the thermally disintegrable layer refers to the surface tension measured, for example, by the wetting tension test method (JIS K6768). If the surface tension of the thermally disintegrable layer is 38 mN / m or more, the activity of the thermally disintegrable layer can be increased, and adhesion to the adherend can be imparted.

[0082] The lower limit of the surface tension of the thermally disintegrable layer is more preferably 38 mN / m or more, even more preferably 41 mN / m or more, and particularly preferably 44 mN / m or more. There is no particular upper limit to the surface tension of the thermally disintegrable layer, but it is more preferable that the upper limit be 73 mN / m or less.

[0083] The surface tension of the thermally disintegrable layer can be adjusted by blending the resin used in the thermally disintegrable layer and additives such as a crosslinking agent and a curing agent.

[0084] (Supporting base material) Furthermore, as described above, the thermally disintegrable sheet of this embodiment may include a supporting substrate as shown in Figure 2. That is, the thermally disintegrable sheet of this embodiment may further include a supporting substrate, and the thermally disintegrable layer may be provided on at least one surface of the supporting substrate. This allows the thermally disintegrable sheet to be processed with high precision by punching or the like. Such a thermally disintegrable sheet is also preferred for applications in which it is processed into a specific shape or is used in a narrow width.

[0085] Furthermore, the thickness of the supporting substrate in this embodiment is preferably 100 μm or less, more preferably 80 μm or less, even more preferably 70 μm or less, even more preferably 50 μm or less, and particularly preferably 30 μm or less. In one aspect, the thickness of the supporting substrate may be 20 μm or less, 12 μm or less, 7 μm or less, or 3 μm or less. There is no particular lower limit to the thickness of the supporting substrate. From the viewpoint of the handleability and processability of the thermally disintegratable sheet, the thickness of the supporting substrate is usually 0.5 μm or more (for example, 1 μm or more). In one aspect, the thickness of the supporting substrate may be 3 μm or more. In another aspect, the thickness of the supporting substrate may be 8 μm or more, or may be 13 μm or more, or may be 16 μm or more.

[0086] The structure and material of the supporting substrate are not particularly limited, and it is typically a film-like substrate (also referred to as a "substrate film"). As the substrate film, one containing a resin film as a base film can be preferably used. The base film is typically a member that can independently maintain its shape (independent). The substrate film in this embodiment may be substantially composed of such a base film. Alternatively, the substrate film may include an auxiliary layer in addition to the base film. Examples of the auxiliary layer include a colored layer, a reflective layer, an undercoat layer, an antistatic layer, etc., provided on the surface of the base film. The substrate film may also be a porous film. The porous film is not particularly limited as long as it has a plurality of pores in the film (as long as pores are formed), and examples thereof include foam films and nonwoven fabrics.

[0087] The resin film is a film whose main component is a resin material (e.g., a component contained in the resin film in an amount exceeding 50% by mass). Examples of resin films include polyolefin-based resin films such as polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymer; polyester-based resin films such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN); polyurethane-based resin films; vinyl chloride-based resin films; vinyl acetate-based resin films; polyimide-based resin films; polyamide-based resin films; fluororesin films; cellophane; and the like. The resin film may also be a rubber-based film such as a natural rubber film or a butyl rubber film. Among these, polyester films are preferred from the viewpoints of handleability and processability, and PET films are particularly preferred.

[0088] <Application> The thermally disintegrable sheet according to the embodiment of the present invention can be used to bond various adherends. The thermally disintegrable sheet according to the embodiment of the present invention can easily destroy the thermally disintegrable layer by applying a stimulus such as heat, and the bonded body can be disassembled without damaging the adherends, making it suitable for bonding adherends made of different materials that need to be separated and recovered, or for temporarily fixing members.

[0089] The thermally disintegrable sheets according to the embodiments of the present invention are suitable for fastening and joining metal parts, resin parts, and metal-resin composite parts used in boats, aircraft, automobiles, and the like. In particular, automobile batteries, bodies, motors, and the like are required to be separated and collected in consideration of environmental issues, and may require dismantling. Furthermore, because the thermally disintegrable sheets according to the embodiments of the present invention are in sheet form, they have excellent processing precision, making them suitable for applications where they can be processed into specific shapes or narrowed for use, such as fastening and joining components in portable electronic devices. Such portable electronic devices and other electronic devices may require dismantling for purposes such as separated collection, repair or replacement of components, or improving productivity through temporary bonding during the manufacturing process.

[0090] [Laminate, Joined Body, Manufacturing Method of Joined Body, and Disassembly Method of Joined Body] The thermally disintegrable sheet according to the embodiment of the present invention can be used in a laminate, a bonded body, a method for manufacturing a bonded body, and a method for dismantling a bonded body.

[0091] The above description can be directly applied to the thermally disintegrable sheet and the thermally disintegrable layer in the laminate, the joined body, the method for manufacturing the joined body, and the method for dismantling the joined body according to the embodiments of the present invention.

[0092] (Laminate, Joint, and Method for Manufacturing Joint) The laminate according to the embodiment of the present invention is a laminate in which a thermally disintegrable sheet is laminated on a resin material. The laminate according to the embodiment of the present invention is preferably a laminate in which a thermally disintegrable layer of the thermally disintegrable sheet is laminated on a resin material. The laminate according to an embodiment of the present invention may be a laminate in which at least a portion of the surface of the thermally disintegratable layer in the thermally disintegratable sheet according to an embodiment of the present invention is laminated on at least a portion of the surface of the resin material, and it is preferable that the laminate is laminated so that at least a portion of the surface of the thermally disintegratable layer is in contact with at least a portion of the surface of the resin material.

[0093] The joined body according to the embodiment of the present invention is a joined body in which the thermally disintegrable sheet according to the embodiment of the present invention is joined to a resin material. The joined body according to the embodiment of the present invention is preferably a joined body in which the thermally disintegrable layer of the thermally disintegrable sheet is joined to a resin material. The bonded structure according to an embodiment of the present invention may be a bonded structure in which at least a portion of the surface of the thermally disintegratable layer in the thermally disintegratable sheet according to an embodiment of the present invention is bonded to at least a portion of the surface of the resin material, and it is preferable that at least a portion of the surface of the thermally disintegratable layer is bonded to at least a portion of the surface of the resin material. The bonded body according to the embodiment of the present invention may be a bonded body in which a resin material is a first member, and the first member and a second member are bonded together via a thermally disintegrable sheet.

[0094] When two or more adherends (e.g., a first member and a second member) are joined using a thermally disintegrable sheet according to an embodiment of the present invention, the thermally disintegrable sheet may be a sheet consisting of only a thermally disintegrable layer without a substrate, a sheet having the thermally disintegrable layer on both sides of a supporting substrate, or a sheet having the thermally disintegrable layer on one side of a supporting substrate and another adhesive layer on the other side. That is, in the laminate and bonded body according to the embodiment of the present invention, a supporting substrate, an adhesive layer other than the thermally disintegrable layer, and the like may be present between the adherend and the thermally disintegrable layer.

[0095] The method for producing a joined body according to an embodiment of the present invention uses a thermally disintegrable sheet according to an embodiment of the present invention. The bonded body may be manufactured and molded using a molding method such as compression molding, transfer molding, injection compression molding, RTM (Resin Transfer Molding) molding, VaRTM (Vacuum assisted Resin Transfer Molding) molding (vacuum impregnation method), autoclave molding, or the like.

[0096] The method for producing a joined body according to an embodiment of the present invention uses a thermally disintegrable sheet according to an embodiment of the present invention.

[0097] The manufacturing method of the joined body according to the embodiment of the present invention includes a lamination step of laminating the thermally disintegrable layer of the thermally disintegrable sheet according to the embodiment of the present invention and a resin material; The method may further include a fusion step of fusion-bonding the thermally disintegratable layer and the resin material.

[0098] A method for producing a joined body according to another embodiment of the present invention includes a laminating step of laminating the thermally disintegratable layer of the thermally disintegratable sheet and a substrate; an impregnation step of impregnating the substrate with a resin composition; a curing step of curing the resin composition to form a resin material; The device may also include:

[0099] Furthermore, the method for producing a bonded body according to the embodiment of the present invention may include a bonding step of curing the thermally disintegrable layer to bond two or more adherends together.

[0100] The resin material in the laminate, the bonded body, and the method for manufacturing the bonded body includes a resin. The resin included in the resin material may be a thermosetting resin or a thermoplastic resin, and examples thereof include polyimide resins, acrylic resins, epoxy resins, polyethernitrile resins, polyethersulfone resins, polyester resins (polyethylene terephthalate resins, polyethylene naphthalate resins, etc.), polyvinyl chloride resins, polyphenylene sulfide resins, polyetheretherketone resins, polyamide resins (so-called aramid resins, etc.), polyarylate resins, polycarbonate resins, and liquid crystal polymers.

[0101] Examples of thermoplastic resins include PP (polypropylene), PA (polyamide), PPE (polyphenylene ether), PPS (polyphenylene sulfide), PET (polyethylene terephthalate), PBT (polybutylene terephthalate), POM (polyacetal), PEEK (polyether ether ketone), PC (polycarbonate), PES (polyether sulfide), EP (epoxy), etc. Among these resins, thermoplastic resins that can advantageously exhibit the effects of the present invention include PPS (polyphenylene sulfide), PA (polyamide), PES (polyether sulfide), and EP (epoxy).

[0102] As the thermoplastic resin, fiber reinforced thermoplastic resin (FRTP) can be used. Examples of fiber reinforced thermoplastic resins (FRTP) include carbon fiber reinforced thermoplastic resins (CFRTP) and glass fiber reinforced thermoplastic resins (GFRTP).

[0103] Examples of carbon fiber reinforced thermoplastic resins (CFRTP) include PPS-based carbon fiber reinforced thermoplastic resins, PA-based carbon fiber reinforced thermoplastic resins, PES-based carbon fiber reinforced thermoplastic resins, EP-based carbon fiber reinforced thermoplastic resins, and PP-based carbon fiber reinforced thermoplastic resins.

[0104] Examples of glass fiber reinforced thermoplastic resins (GFRTP) include PPS-based glass fiber reinforced thermoplastic resins, PA-based glass fiber reinforced thermoplastic resins, and PP-based glass fiber reinforced thermoplastic resins.

[0105] The resin contained in the resin material may be a thermosetting resin, or from the viewpoint of improving the adhesion between the resin material or resin composition and the thermally disintegratable layer, may be a thermosetting resin containing an unsaturated hydrocarbon group. Examples of the unsaturated hydrocarbon group-containing thermosetting resin include unsaturated polyester resin and vinyl ester resin, with unsaturated polyester resin being preferred. The unsaturated hydrocarbon group-containing thermosetting resin contained in the resin material includes at least a portion of the unsaturated hydrocarbon group-containing thermosetting resin in an uncured state.

[0106] The resin material may include a fiber-reinforced resin, and the thermosetting resin may be a fiber-reinforced thermosetting resin. Examples of the fiber-reinforced thermosetting resin include carbon fiber-reinforced thermosetting resin and glass fiber-reinforced thermosetting resin.

[0107] The resin material preferably contains a reactive monomer, a curing agent, and glass fiber in addition to the unsaturated hydrocarbon group-containing thermosetting resin. The unsaturated hydrocarbon group-containing thermosetting resin, such as an unsaturated polyester resin, undergoes radical polymerization of the unsaturated hydrocarbon group in the thermosetting resin and the reactive monomer in the presence of the curing agent to form a polymer (three-dimensional crosslinking), thereby obtaining a cured product. When the resin contained in the resin material is an unsaturated polyester resin, for example, styrene is preferably used as the reactive monomer, and benzoyl peroxide (BPO) is preferably used as the curing agent.

[0108] The shape of the resin material is not particularly limited, but examples thereof include a plate having a flat surface, a plate having a curved surface, a plate having an uneven surface, a sheet, and a film. The thickness of the resin material is not particularly limited, but is, for example, 0.001 mm to 30 mm.

[0109] Examples of the substrate in the method for producing the bonded body include substrates formed of glass, resin (e.g., polyethylene, aramid, etc.), cellulose, carbon fiber, etc. These are preferably fiber assemblies, and the fiber assemblies may be, for example, nonwoven fabrics, woven fabrics, intersection-welded meshes, etc. More specifically, examples include glass cloth and carbon cloth, with glass cloth being preferred.

[0110] The materials for the first and second members constituting the adherend and laminate are not particularly limited, but examples include metal materials such as copper, silver, gold, iron, tin, palladium, aluminum, nickel, titanium, chromium, zinc, etc., or alloys containing two or more of these, as well as inorganic materials such as the above-mentioned resin materials, alumina, zirconia, soda glass, quartz glass, and carbon. The resin composition used in the method for producing the bonded body is not particularly limited as long as it is a composition that can form a resin material, and examples thereof include resin compositions that can form the above-mentioned resin materials.

[0111] The adherend may have either a single layer structure or a multilayer structure, and the surface to which the thermally disintegrable sheet is attached (attachment surface) may be subjected to various surface treatments.

[0112] In a method for manufacturing a bonded body using a thermally disintegrable sheet configured in this manner, for example, the thermally disintegrable sheet is laminated between a first member and a second member, which are adherends. Then, by applying pressure and heating to the first member and the second member in a direction that brings them into close contact with each other, the first member and the thermally disintegrable layer are fused together, and the thermally disintegrable layer and the second member are fused together, resulting in a bonded body in which the first member and the second member are bonded via the thermally disintegrable sheet (which may be the thermally disintegrable layer). Thereafter, by hardening the thermally disintegrable layer of the bonded body bonded using the thermally disintegrable sheet, a bonded body in which the first member and the second member are more firmly bonded via the thermally disintegrable sheet (which may be the thermally disintegrable layer) is obtained.

[0113] (Method of dismantling the joint) A method for dismantling a bonded structure according to an embodiment of the present invention is a method for dismantling a bonded structure including a thermally degradable layer, comprising: The thermally disintegrable layer has an elastic modulus E' at 25°C 25 is 10 6 Pa or more 10 10 Pa or less, Elastic modulus E' at 110°C 110 is 10 7 Pa or less, The elastic modulus E' at 25°C25 The elastic modulus E' at 110°C 110 is more than 100 times The method includes heating at least a portion of the bonded body to destroy the thermally decomposable layer. The bonded body including the thermally disintegrable layer may be a bonded body bonded using the thermally disintegrable sheet according to an embodiment of the present invention.

[0114] In the method for dismantling a bonded body according to the embodiment of the present invention, the heating temperature when at least a part of the bonded body is heated can be appropriately selected depending on the type of resin contained in the thermally dismantlable layer used in the bonded body.

[0115] In the method for dismantling a bonded body according to an embodiment of the present invention, by heating at least a part of the bonded body, the thermally dismantlable layer softens, and the bonded body can be dismantled without damaging the adherends, thereby separating the first member and the second member.

[0116] When two or more components are joined or separated using a thermally disintegrable sheet in this way, it is preferable to satisfy the relationship X≧Y, where X°C is the temperature when the thermally disintegrable layer is joined to two or more components and Y°C is the temperature when the thermally disintegrable layer is destroyed and the joined body is disassembled. This is because softening the thermally disintegrable layer allows it to conform to the irregularities of the two or more components. Furthermore, if the thermally disintegrable layer contains a curing agent, it is preferable to allow the curing reaction to proceed at X°C.

[0117] The heating temperature may be Tα° C. calculated by the following formula (1). Tα℃ = melting or decomposition temperature of the thermally degradable layer (Tm)℃ - 10℃ (1)

[0118] The melting temperature or decomposition temperature (Tm) of the thermally disintegrable layer can be measured as follows. That is, when the resin contained in the thermally disintegratable layer is a thermosetting resin, the storage modulus and loss modulus are measured, the value of tan δ (E" (loss modulus) / E' (storage modulus)) is calculated, and the peak temperature of tan δ on the high temperature side is taken as the melting point (Tm). When the resin contained in the thermally disintegrable layer is a thermoplastic resin, the melting point (T1) can be measured in the same manner. In addition, when the resin contained in the thermally disintegratable layer is an amorphous resin, it does not have a melting point, so the decomposition temperature is regarded as the melting point.

[0119] The heating temperature is not particularly limited as long as it is a temperature at which the bonded body can be disassembled, and is preferably higher than the glass transition temperature Tg of the resin contained in the thermally disintegrable layer, and is preferably Tg-20°C or higher, more preferably Tg-10°C or higher, and even more preferably Tg°C or higher. More specifically, it is preferably 60°C or higher, and more preferably 80°C or higher. The upper limit of the heating temperature is, for example, preferably 170°C or lower, more preferably 150°C or lower, and even more preferably 130°C or lower. The glass transition temperature of the resin contained in the thermally disintegrable layer can be calculated by a known method.

[0120] The heating temperature may be a temperature (Tβ° C.) at which the shear adhesive strength measured under the conditions below using a sample prepared as described below becomes less than 10 MPa. That is, the sample is obtained by laminating a CFRP (Carbon Fiber Reinforced Plastics) prepreg sheet and a thermally degradable layer to form a laminate structure of CFRP prepreg sheet / thermal degradable layer / CFRP prepreg sheet, heating the laminate at 80°C for 10 minutes, and then heating and pressuring it at 130°C for 20 minutes at 2 Pa. The temperature at which the shear adhesive strength measured using the obtained sample at a tensile speed of 1.3 mm / min becomes less than 10 MPa is defined as Tβ°C.

[0121] As described above, the present specification discloses the following: <1> A thermally disintegrable sheet comprising a thermally disintegrable layer, The thermally disintegratable layer is Elastic modulus E' at 25°C 25 is 10 6 Pa or more 10 10 Pa or less, Elastic modulus E' at 110℃ 110 is 10 7 Pa or less, The elastic modulus E' at 25°C 25 The elastic modulus E' at 110°C 110 A thermally disintegrable sheet that is 100 times or more stronger than the original. <2> The thermally disintegratable layer has a disintegration temperature of 80°C to 130°C. <1> The thermally disintegrable sheet according to claim 1. <3> The thermally disintegrable layer has a shear adhesive strength F 25 and shear adhesive strength F at 110°C 110 and satisfy the following formula (1): <1> or <2> The thermally disintegrable sheet according to claim 1. F 110 / F 25 <0.5 Equation (1) <4> The thermally disintegratable layer contains a resin. <1> ~ <3> 10. The thermally disintegrable sheet according to any one of the preceding items. <5> The resin contains at least one selected from polyamide resin, acrylic rubber, and epoxy resin. <4> The thermally disintegrable sheet according to claim 1. <6> The resin includes an epoxy-modified resin. <4> The thermally disintegrable sheet according to claim 1. <7> <1> ~ <6> 10. A thermally disintegrable sheet with a release liner, wherein at least one surface of the thermally disintegrable layer in the thermally disintegrable sheet according to any one of claims 1 to 9 is protected by a release liner. <8> <1> ~ <6> 10. A laminate in which the thermally disintegrable sheet according to any one of claims 1 to 9 is laminated on a resin material. <9> <1> ~ <6> 10. A bonded body in which the thermally disintegratable sheet according to any one of claims 1 to 9 is bonded to a resin material. <10> the resin material is a first member, The first member and the second member are joined using the thermally disintegrable sheet. <9> The conjugate according to claim 1. <11> The resin material includes a thermosetting resin. <9> or <10> The conjugate according to claim 1. <12> <1> ~ <6> 1. A method for producing a bonded body using the thermally disintegrable sheet according to any one of claims 1 to 9. <13> a lamination step of laminating the thermally disintegratable sheet and a resin material; a fusion step of fusing the thermally disintegratable layer and the resin material, <12> A method for producing the bonded body according to claim 1. <14> a lamination step of laminating the thermally disintegrable sheet and a substrate; an impregnation step of impregnating the substrate with a resin composition; a curing step of curing the resin composition to form a resin material; Equipped with <12> A method for producing the bonded body according to claim 1. <15> A method for dismantling a bonded structure including a thermally dismantlable layer, comprising: The thermally disintegrable layer has an elastic modulus E' at 25°C 25 is 10 6 Pa or more 10 10 Pa or less, Elastic modulus E' at 110°C 110 is 10 7 Pa or less, The elastic modulus E' at 25°C 25 The elastic modulus E' at 110°C 110 is more than 100 times A method for disassembling a bonded body, comprising the step of heating at least a part of the bonded body to destroy the thermally disintegrable layer. [Example]

[0122] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples in any way.

[0123] Example 1 A polyamide resin solution was obtained by adding a mixed solvent of ethanol (EtOH) / isopropyl alcohol (IPA) / water (68% by mass / 12% by mass / 20% by mass) to a polyamide copolymer (Platamid M1276, manufactured by Arkema) to a solids content of 20% by mass, and stirring thoroughly while heating at 40°C. 500 parts by mass of the polyamide resin solution (100 parts by mass as polyamide resin) and 0.5 parts by mass of KBM-403 were then added to obtain a thermally disintegrable composition. Next, the thermally disintegrable composition was applied using an applicator to the release-treated surface of a 75 μm-thick PET release liner having a release-treated surface, to form a layer so that the dry thickness would be the thickness shown in Table 1. Next, the composition was heated at 100°C for 2 minutes to dry off the solvent, thereby producing a thermally disintegrable layer (thermally disintegrable sheet).

[0124] [Examples 2 and 3, Comparative Examples 2 and 3] Thermally disintegrable sheets were produced in the same manner as in Example 1, except that the types and amounts of the various raw materials used in producing the thermally disintegrable sheets were changed as shown in Table 1 or 2.

[0125] Example 4 Bisphenol A phenoxy resin (jER-1256B40, manufactured by Mitsubishi Chemical Corporation) was applied using an applicator to the release-treated surface of a 75 μm thick PET release liner having a release-treated surface, to form a layer with a dry thickness shown in Table 1. The layer was then heated at 60°C for 10 minutes to dry out the solvent, producing a thermally disintegrable layer (thermally disintegrable sheet).

[0126] Example 5 Methyl ethyl ketone (MEK) was added to epoxy resin-modified acrylic rubber (HyPoxRK84L, manufactured by HUNTSMAN) to a solids ratio of 50% by mass, and the mixture was thoroughly stirred to obtain a thermally disintegrable composition. The thermally disintegrable composition was applied using an applicator to the release-treated surface of a 75 μm-thick PET release liner having a release-treated surface, so that the dry thickness would be the thickness shown in Table 1, to form a layer. The mixture was then heated at 60°C for 10 minutes to dry off the solvent, producing a thermally disintegrable layer (thermally disintegrable sheet).

[0127] Example 6 Methyl ethyl ketone (MEK) was added to epoxy resin-modified acrylic rubber (HyPoxRK84L, manufactured by HUNTSMAN) to a solids content of 50% by mass, and the mixture was thoroughly stirred to obtain a thermally degradable composition. 200 parts by mass of the thermally degradable composition (100 parts by mass of HyPoxRK84L) was mixed with 5 parts by mass of RY-200, and MEK was added to a solids content of 50% by mass. The mixture was then stirred at 2000 rpm for 1 minute using a high-speed mixer, and further degassed at 2000 rpm for 1 minute using a planetary mixer to produce a thermally degradable composition. Next, the thermally disintegrable composition was applied using an applicator to the release-treated surface of a 75 μm-thick PET release liner having a release-treated surface, to form a layer so that the dry thickness would be the thickness shown in Table 1. Next, the composition was heated at 60°C for 10 minutes to dry out the solvent, thereby producing a thermally disintegrable layer (thermally disintegrable sheet).

[0128] [Comparative Examples 4 and 5] Sheets were produced in the same manner as in Example 6, except that the types and amounts of the various raw materials used in producing the thermally disintegrable sheets were changed as shown in Table 2.

[0129] 〔evaluation〕 (1) Elastic modulus E' of Examples 1 to 6 and Comparative Examples 2 to 5 The thermally disintegrable sheets produced in Examples 1 to 6 and Comparative Examples 2 to 5 were cut into pieces 10 mm wide x 50 mm long, and the release liners were peeled off to obtain the thermally disintegrable layer as a specimen. Using a rheometer (product name "RSA G2", manufactured by TA Instruments), the dynamic viscoelasticity was measured under the conditions of a frequency of 1 Hz, a heating rate of 5°C / min, and a measurement temperature of -40 to 200°C. The sheets of Comparative Examples 4 and 5 were heated in advance at 100° C. for 60 minutes to prepare specimens for evaluation. In this manner, the elastic modulus E' was measured at each temperature. If the sample is destroyed during measurement or if the 4 The measurement was stopped when the elastic modulus was 1.0 × 10 4 It was recorded as below Pa.

[0130] (2) Elastic modulus E' of Comparative Example 6 The thermally disintegrable layers of the thermally disintegrable sheet produced in Comparative Example 6 were laminated to a thickness of 1 mm or more and cut into a diameter of 8 mm. Using a rheometer (product name "ARES G2", manufactured by TA Instruments), the dynamic viscoelasticity was measured at a frequency of 1 Hz, a heating rate of 5°C / min, and a measurement temperature of 0 to 100°C. During the measurement, the elastic modulus E' became 10 MPa or less at temperatures below 100°C, so the measurement was stopped, and the elastic modulus was 1.0 x 10 4 It was recorded as below Pa.

[0131] (3) Handling The thermally disintegrable sheets produced in the Examples and Comparative Examples were cut into 25 mm wide x 12.5 mm pieces. The thermally disintegrable layer was then peeled off from the release liner. If the thermally disintegrable layer could be laminated to the carbon fiber in a single layer without stretching or blocking, the handling was evaluated as "Good." If the layer could not be laminated to the carbon fiber due to stretching or blocking, the handling was evaluated as "Poor."

[0132] (4) Shear adhesive strength Using the thermally disintegrable sheets produced in Examples 1 to 6 and Comparative Examples 2 to 5 and the CFRP prepregs, test pieces (joints) for shear adhesive strength tests were produced by press molding. First, prepreg sheets made by laminating four layers of CFRP prepreg (3K, plain weave, thermosetting epoxy resin system) were cut into two sheets (prepreg sheet 21) measuring 25 mm wide x 80 mm long, and two sheets (prepreg sheet 22) measuring 25 mm wide x 60 mm long. Also, a thermally disintegrable sheet was cut into a sheet measuring 25 mm wide x 12.5 mm long (thermally disintegrable sheet 11). The cut prepreg sheets 21, 22 and thermally disintegrable sheet 11 were laminated as shown in FIG. Next, as shown in Figure 5, the laminate 300 was sandwiched between a 75 µm thick PET release liner 24 and a 2 mm thick aluminum plate 25. After heating at 80°C for 10 minutes, it was heated at 130°C for 20 minutes while pressurizing at 2 MPa so that the thickness became 1.8 mm, thereby obtaining a test specimen for measuring shear adhesive strength. In Comparative Example 1, no thermally disintegratable sheet was used, and only CFRP prepregs (prepreg sheets 21 and 22) were used to prepare the test specimen. Both ends of the obtained test piece were fixed with 25 mm chucks of a tensile tester, and the tester was moved at a rate of 1.3 mm / min until breakage occurred, and the maximum stress was taken as the shear adhesive strength at 25°C. For measurement of the shear adhesive strength at a temperature of 110°C, the specimen was fixed with a chuck, held under heated conditions for 10 minutes, and then the measurement was carried out.

[0133] The bond strength was evaluated as "good" when the shear adhesive strength at room temperature (25)°C was greater than 15 MPa, "fair" when it was 10 MPa to 15 MPa, and "poor" when it was less than 10 MPa. Dismantling properties were evaluated as follows: adhesive strength at shear at 110°C of less than 7.5 MPa was rated "Good", adhesive strength between 7.5 MPa and 10 MPa was rated "Average", and adhesive strength greater than 10 MPa was rated "Poor".

[0134] The evaluation results of Examples 1 to 6 and Comparative Examples 1 to 6 are shown in Tables 1 and 2 below.

[0135] [Table 1]

[0136] [Table 2]

[0137] Each component listed in Tables 1 and 2 is described below. M1276: Polyamide copolymer, Platamid M1276, manufactured by Arkema CM8000: Polyamide copolymer, Amilan CM8000, manufactured by Toray Industries, Inc. Ultramid IC: Polyamide copolymer, Ultramid 1C, manufactured by BASF jER-834: Bisphenol A epoxy resin, jER-834, manufactured by Mitsubishi Chemical Corporation jER-1256B40: Bisphenol A phenoxy resin, jER-1256B40, manufactured by Mitsubishi Chemical Corporation HyPoxRK84L: Epoxy resin modified acrylic rubber, HyPoxRK84L, manufactured by HUNTSMAN RY-200: Silica filler, Aerosil RY-200, manufactured by Nippon Aerosil Co., Ltd. M5: Silica filler, M5 Cab-o-sil, manufactured by CABOT KBM403: Epoxy silane coupling agent, KBM-403, manufactured by Shin-Etsu Silicone Co., Ltd. TETRAD-C: Multifunctional epoxy resin, TETRAD-C, manufactured by Mitsubishi Gas Chemical Company, Inc. DDA-50: Dicyandiamide, Omicure DDA-50, manufactured by HUNTSMAN U-24M: 1,1'-(4-methyl-1,3-phenylene)bis(3,3'-dimethylurea), Omicure U-24M, manufactured by HUNTSMAN [Explanation of symbols]

[0138] 100 Thermally decomposable sheet 11 Thermodegradable layer 12 Supporting base material 200 zygote 14 First member 15 Second member 30 Media 31, 32 Glass cloth 35 Aluminum alloy 36 Sealant Tape 40 nylon hose 50 bags of film

Claims

1. A thermally disintegrable sheet comprising a thermally disintegrable layer, The thermally disintegratable layer is Elastic modulus E' at 25°C ２５ is 10 ６ Pa or more 10 １０ Pa or less, Elastic modulus E' at 110°C １１０ is 10 ７ Pa or less, The elastic modulus E' at 25°C ２５ The elastic modulus E' at 110°C １１０ The thermally disintegrable sheet has a hardness of 100 times or more.

2. 2. The thermally disintegrable sheet according to claim 1, wherein the thermally disintegrable layer has a disintegration temperature of 80°C to 130°C.

3. The thermally disintegratable layer has a shear adhesive strength F ２５ and shear adhesive strength F at 110 ° C. １１０ 2. The thermally disintegrable sheet according to claim 1, wherein F １１０ / F ２５ <0.5 Formula (1)

4. The thermally disintegrable sheet according to claim 1 , wherein the thermally disintegrable layer comprises a resin.

5. The thermally disintegrable sheet according to claim 4, wherein the resin comprises at least one selected from the group consisting of polyamide resin, acrylic rubber, and epoxy resin.

6. The thermally disintegrable sheet according to claim 4 , wherein the resin comprises an epoxy-modified resin.

7. A thermally disintegrable sheet with a release liner, wherein at least one surface of the thermally disintegrable layer in the thermally disintegrable sheet according to any one of claims 1 to 6 is protected by a release liner.

8. A laminate in which the thermally disintegrable sheet according to any one of claims 1 to 6 is laminated on a resin material.

9. A bonded body obtained by bonding the thermally disintegrable sheet according to any one of claims 1 to 6 and a resin material.

10. the resin material is a first member, The joined body according to claim 9 , wherein the first member and the second member are joined together using the thermally disintegrable sheet.

11. The bonded structure according to claim 9 , wherein the resin material comprises a thermosetting resin.

12. A method for producing a bonded body using the thermally disintegrable sheet according to any one of claims 1 to 6.

13. a lamination step of laminating the thermally disintegratable sheet and a resin material; a fusion step of fusing the thermally disintegratable layer and the resin material, The method for producing the bonded body according to claim 12 .

14. a lamination step of laminating the thermally disintegrable sheet and a substrate; an impregnation step of impregnating the substrate with a resin composition; a curing step of curing the resin composition to form a resin material; Equipped with The method for producing the bonded body according to claim 12 .

15. A method for dismantling a bonded structure including a thermally dismantlable layer, comprising: The thermally disintegratable layer has an elastic modulus E' at 25°C. ２５ is 10 ６ Pa or more 10 １０ Pa or less, Elastic modulus E' at 110°C １１０ is 10 ７ Pa or less, The elastic modulus E' at 25°C ２５ The elastic modulus E' at 110°C １１０ is more than 100 times A method for disassembling a bonded body, comprising the step of heating at least a part of the bonded body to destroy the thermally disintegrable layer.

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