Resin composition, laminate with adhesive layer, coverlay film, bonding sheet, electromagnetic shield material and composite body

Abstract

To provide a resin composition which suppresses occurrence of appearance abnormality in a used place due to heating, and can maintain adhesive strength of an adhesive part, and a laminate with an adhesive layer, a coverlay film, a bonding sheet and a composite body which contain the resin composition.SOLUTION: A resin composition contains at least one of a polyurethane resin (A) and a polyolefin resin (B), a melamine resin (C), and an epoxy resin (D), wherein the melamine resin (C) is 0.2 pts.mass to 10 pts.mass with respect to 100 pts.mass of the total amount of the polyurethane resin (A) and the polyolefin resin (B).SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a resin composition, a laminate with an adhesive layer, a coverlay film, a bonding sheet, an electromagnetic shielding material, and a composite.

Background Art

[0002] Resin compositions are used in various applications such as adhesives and coating agents. And, studies are being conducted on components and compositions for the purpose of improving the performance of resin compositions according to the application. Patent Document 1 discloses a thermosetting resin composition having excellent electrical insulation reliability under severe conditions, which includes a solid epoxy resin at 25°C, a non-solid epoxy resin at 25°C, fine particle rubber dispersed in the non-solid epoxy resin, a curing agent, an inorganic filler, and a polyurethane derived from polycarbonate diol.

[0003] Further, Patent Document 2 discloses an adhesive composition having excellent heat resistance and adhesive strength, low relative permittivity and dielectric loss tangent, and excellent dielectric properties, which includes an acid-modified resin, a compound having a terminal unsaturated hydrocarbon group, and a compound having an epoxy group and a terminal unsaturated hydrocarbon group.

[0004] Furthermore, Patent Document 3 discloses an adhesive composition having excellent adhesiveness and electrical properties, and also excellent solder heat resistance, which is an adhesive composition containing a modified polyolefin-based resin and an epoxy resin, wherein the modified polyolefin resin is a resin graft-modified with a modifier containing an α,β-unsaturated carboxylic acid or a derivative thereof, and the epoxy resin is two or more types.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

[0006] However, when an adhesive containing a conventional adhesive composition such as the adhesive composition disclosed in Patent Documents 1 to 3 is used for a flexible printed wiring board or the like, when heating is performed in a solder reflow process or the like, the adhesive absorbs moisture or decomposition gas is generated from the adhesive, resulting in problems such as appearance abnormalities such as swelling at the location where the adhesive is used and a decrease in the adhesive strength of the bonded portion.

[0007] In view of such circumstances, the present disclosure aims to provide a resin composition in which the occurrence of appearance abnormalities at the location of use is suppressed even by heating and the adhesive strength of the bonded portion can be maintained, and further to provide a laminate with an adhesive layer, a coverlay film, a bonding sheet, and a composite containing the resin composition. [Means for Solving the Problems]

[0008] The present disclosure that has achieved the above-described object includes the following. <1>A resin composition comprising at least one of a polyurethane resin (A) and a polyolefin resin (B), a melamine resin (C), and an epoxy resin (D), wherein the melamine resin (C) is 0.2 parts by mass to 10 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin (A) and the polyolefin resin (B). <2>The resin composition according to <1> above, wherein the polyurethane resin (A) contains a polyphenylene ether having at least two hydroxy groups in the molecule and a polyurethane resin containing a polyisocyanate as a polymerization component. <3>The resin composition according to <1> or <2> above, wherein the polyolefin resin (B) is a resin obtained by graft-modifying an unmodified polyolefin resin with a modifier containing an α,β-unsaturated carboxylic acid or a derivative thereof. <4>The melamine resin (C) is the resin composition according to any one of <1> to <3> above, which contains at least one alkylated melamine selected from the group consisting of imino-type alkylated melamine, methylol-type alkylated melamine, iminomethylol-type alkylated melamine, and fully etherified alkylated melamine as a constituent unit. <5>The resin composition according to any one of <1> to <4> above, wherein at least one of the polyurethane resin (A) and the polyolefin resin (B) has a weight average molecular weight of 30,000 or more. <6>The resin composition according to any one of <1> to <5> above, which contains 1 to 60 parts by mass of the epoxy resin (D) with respect to 100 parts by mass of the polyurethane resin (A) and the polyolefin resin (B). <7>The resin composition according to any one of <1> to <6> above, which further contains a conductive filler (E). <8>The resin composition according to <7> above, which contains 10 to 350 parts by mass of the conductive filler (E) with respect to a total of 100 parts by mass of the polyurethane resin (A), the polyolefin resin (B), and the epoxy resin (D). <9>The resin composition according to any one of <1> to <8> above, which is an adhesive composition. <10>An adhesive layer laminate comprising a base material and an adhesive layer containing the resin composition according to <9> above disposed on the base material. <11>A coverlay film comprising an insulating film and an adhesive layer containing the resin composition according to <9> above disposed on the insulating film. <12>A bonding sheet comprising a release film and an adhesive layer containing the resin composition according to <9> above disposed on the release film. <13>An electromagnetic wave shielding material comprising an adhesive layer or a cured layer containing the resin composition according to <9> above. <14>A composite body comprising an adherend and a cured layer containing the resin composition according to <9> above disposed on the surface of the adherend.

Advantages of the Invention

[0009] According to the resin composition of the present disclosure, it is possible to provide an adhesive layer or a cured layer that can suppress the occurrence of appearance abnormalities at the place of use even by heating and can maintain the strength of the bonded portion. Further, by using the resin composition of the present disclosure, it is possible to provide a laminate with an adhesive layer, a coverlay film, a bonding sheet, and a composite that can suppress the occurrence of appearance abnormalities at the place of use even by heating and can maintain the strength of the bonded portion.

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments. In the following embodiments, the components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values and ranges thereof, and they do not limit the present disclosure. For example, the present disclosure can be added, omitted, substituted, changed, etc. with respect to numbers, amounts, positions, ratios, materials, configurations, types, orders, etc. without departing from the gist.

[0011] In the present disclosure, "A and / or B" is synonymous with "at least one of A and B". That is, "A and / or B" means that it may be only A, only B, or a combination of A and B.

[0012] In the present disclosure, the numerical range indicated by using "~" indicates a range including the numerical values described before and after "~" as the minimum value and the maximum value, respectively. In the numerical ranges described step by step in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of the numerical range described in other step-by-step descriptions. Further, in the numerical ranges described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

[0013] In the present disclosure, the term "step" includes not only an independent step but also this term if the purpose of the step is achieved even when it cannot be clearly distinguished from other steps.

[0014] When referring to the amount of each component in the composition in the present disclosure, when there are multiple substances corresponding to each component in the composition, unless otherwise specified, it means the total amount of the multiple substances present in the composition.

[0015] The particles corresponding to each component in the present disclosure may include multiple types. When there are multiple types of particles corresponding to each component in the composition, unless otherwise specified, the particle size of each component means a value for the mixture of the multiple types of particles present in the composition.

[0016] When showing a compound by a structural formula in the present disclosure, it may be shown by a structural formula in which the symbols (C and H) representing carbon atoms and hydrogen atoms in the hydrocarbon group and / or hydrocarbon chain are omitted.

[0017] In addition, in the present disclosure, the values of the number average molecular weight (Mn) and weight average molecular weight (Mw) of the resin are molecular weights in terms of polystyrene that can be measured by gel permeation chromatography (GPC).

[0018] <Resin composition> The resin composition of the present disclosure includes at least one of a polyurethane resin (A) and a polyolefin resin (B), a melamine resin (C), and an epoxy resin (D), and the melamine resin (C) is 0.2 parts by mass to 10 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin (A) and the polyolefin resin (B).

[0019] The adhesive layer or cured layer containing the resin composition of the present disclosure cures by the reaction of the functional group of the polyurethane resin (A) and / or the polyolefin resin (B) with the epoxy group of the epoxy resin (D). In particular, in the adhesive layer or cured layer containing the resin composition of the present disclosure, the melamine resin (C) forms a crosslinking reaction with the epoxy resin (D), or the melamine resin (C) forms an interaction with a substrate or an adherend, etc., so that the occurrence of appearance abnormalities can be suppressed even by heating, and the strength of the bonded part can be maintained.

[0020] [Polyurethane resin (A)] In the resin composition of the present disclosure, the polyurethane resin (A) is not particularly limited, but examples include a polyphenylene ether polyurethane resin (A1) containing a polyphenylene ether having at least two hydroxy groups in the molecule and a polyisocyanate as polymerization components, and a polyester polyurethane resin (A2). In the resin composition of the present disclosure, as the polyurethane resin (A), either one or both of the polyphenylene ether polyurethane resin (A1) and the polyester polyurethane resin (A2) can be used.

[0021] [Polyphenylene ether polyurethane resin (A1)] The polyphenylene ether polyurethane resin (A1) contains at least a polyphenylene ether having at least two hydroxy groups in the molecule and a polyisocyanate as polymerization components. That is, the polyphenylene ether polyurethane resin (A1) is at least a reaction product of a polyphenylene ether having at least two hydroxy groups in the molecule and a polyisocyanate.

[0022] Hereinafter, the polymerization components and physical properties of the polyphenylene ether polyurethane resin (A1) will be described in detail.

[0023] -Polyphenylene ether polyol- In the present disclosure, a polyphenylene ether having at least two hydroxy groups in the molecule is also referred to as a "polyphenylene ether polyol". The polyphenylene ether polyol may have a hydroxy group at the end of the molecule or may have a hydroxy group at a non-terminal position of the molecule. The polyphenylene ether polyol may be any of a diol, a triol, a tetraol, etc., and a diol is preferable in an example of the embodiment. In the present disclosure, a polyphenylene ether having two hydroxy groups in the molecule is also referred to as a "polyphenylene ether diol".

[0024] For the phenylene in the polyphenylene ether polyol, regarding the linking position in the main chain, it may be any of o-phenylene (1,2-phenylene), m-phenylene (1,3-phenylene), and p-phenylene (1,4-phenylene), and it is preferably p-phenylene (1,4-phenylene). The linking positions of the phenylene in the molecule may all be the same or not.

[0025] The phenylene in the polyphenylene ether polyol may be unsubstituted or may have substituents. Examples of the substituents include linear or branched alkyl groups having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group. The substituents in the molecule may all be the same group or not.

[0026] An example of an embodiment of the polyphenylene ether polyol has a phenylene oxide substituted with two alkyl groups as a structural unit. In this embodiment, the alkyl group is preferably a linear or branched alkyl group having 1 to 4 carbon atoms. The alkyl groups in the molecule may all be the same group or not.

[0027] An example of an embodiment of the polyphenylene ether polyol has 2,6-dialkyl-1,4-phenylene oxide as a structural unit. In this embodiment, the alkyl group is preferably a linear or branched alkyl group having 1 to 4 carbon atoms. The alkyl groups in the molecule may all be the same group or not.

[0028] An example of an embodiment of the polyphenylene ether polyol has a phenylene oxide substituted with two methyl groups (i.e., dimethylphenylene oxide) as a structural unit. An example of an embodiment of the polyphenylene ether polyol has 2,6-dimethyl-1,4-phenylene oxide as a structural unit.

[0029] There is no limitation on the molecular weight of the polyphenylene ether polyol. The number average molecular weight (Mn) of the polyphenylene ether polyol is preferably 500 to 10,000, more preferably 700 to 8,000, and even more preferably 1,000 to 6,000 in an example of the embodiment.

[0030] An example of an embodiment of the polyphenylene ether polyol is a compound represented by the following formula (1).

[0031]

Chemical formula

[0032] In formula (1), L represents a single bond or a divalent linking group, R represents a hydrogen atom or an alkyl group, and m and n each independently represent an integer of 1 or more. All the Rs in the molecule may be the same group or may not be the same group.

[0033] Examples of the divalent linking group represented by L include an oxygen atom and -C(R1)(R2)-. Here, R1 and R2 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, or a phenyl group. The hydrogen atoms of the alkyl group and the phenyl group may be substituted with a halogen atom (for example, a fluorine atom). R1 and R2 may be linked to each other to form a ring.

[0034] Specific examples of -C(R1)(R2)- are given below, but -C(R1)(R2)- is not limited thereto. In the following structural formulas, "*" means the linking position to the main chain.

[0035]

Chemical formula

[0036] In formula (1), R is preferably a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. All the Rs in the molecule may or may not be the same group.

[0037] In formula (1), the sum of m and n is preferably a number corresponding to the above-mentioned number-average molecular weight.

[0038] An example of an embodiment of the polyphenylene ether polyol is a compound represented by the following formula (2).

[0039]

Chemical formula

[0040] In formula (2), L represents a single bond or a divalent linking group, R represents a hydrogen atom or an alkyl group, and m and n each independently represent an integer of 1 or more. All the Rs in the molecule may or may not be the same group.

[0041] L in formula (2) has the same meaning as L in formula (1), and the specific forms and preferred forms are also the same.

[0042] R in formula (2) is preferably a linear or branched alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. All the Rs in the molecule may or may not be the same group.

[0043] m and n in formula (2) have the same meaning as m and n in formula (1), and the specific forms and preferred forms are also the same.

[0044] An example of an embodiment of the polyphenylene ether polyol is a compound represented by the following formula (3).

[0045]

Chemical formula

[0046] In formula (3), p and q each independently represent an integer of 1 or more. In formula (3), the sum of p and q is preferably a number corresponding to the number average molecular weight described above.

[0047] Examples of commercially available products of the compound represented by formula (3) include Noryl SA90 (SABIC) and OPE (Mitsubishi Gas Chemical).

[0048] The polyphenylene ether polyol may be used alone or in combination of two or more.

[0049] From the viewpoints of increasing the Tg of the polyurethane and suppressing the water absorption rate of the polyurethane, the proportion of the polyphenylene ether polyol in all the polymerization components of the polyphenylene ether polyurethane resin (A1) is preferably 30% by mass or more, more preferably 50% by mass or more, and still more preferably 70% by mass or more. From the viewpoint of imparting flexibility to the polyurethane, the proportion of the polyphenylene ether polyol in all the polymerization components of the polyphenylene ether polyurethane resin (A1) is preferably 95% by mass or less, more preferably 90% by mass or less, and still more preferably 80% by mass or less.

[0050] - Polyisocyanate - The polyisocyanate may be any of diisocyanate, triisocyanate, tetraisocyanate, etc., and diisocyanate is preferable in an example of the embodiment.

[0051] Examples of the polyisocyanate include aromatic diisocyanate, aralkyl diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, and derivatives of these diisocyanates.

[0052] Examples of the aromatic diisocyanate include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, diphenyl ether-4,4'-diisocyanate, and the like.

[0053] Examples of the aralkyl diisocyanate include m-xylylene diisocyanate, p-xylylene diisocyanate, tetramethyl-m-xylylene diisocyanate, and the like.

[0054] Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 1,3-butylene diisocyanate, 2,3-butylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and the like.

[0055] Examples of alicyclic diisocyanates include 1,3 - cyclopentane diisocyanate, 1,3 - cyclohexane diisocyanate, 1,4 - cyclohexane diisocyanate, 1 - methylcyclohexane - 2,4 - diisocyanate, 1 - methylcyclohexane - 2,6 - diisocyanate, 1,3 - bis(isocyanatomethyl)cyclohexane, 1,4 - bis(isocyanatomethyl)cyclohexane, 1,3 - bis(isocyanatoethyl)cyclohexane, 1,4 - bis(isocyanatoethyl)cyclohexane, 4,4’ - methylenebis(cyclohexyl isocyanate), norbornane - 2,5 - diyl diisocyanate, norbornane - 2,6 - diyl diisocyanate, norbornane - 2,5 - diyl bis(methylene)diisocyanate, norbornane - 2,6 - diyl bis(methylene)diisocyanate, isophorone diisocyanate, and the like.

[0056] Examples of derivatives of diisocyanates include polyisocyanates having a uretdione group obtained by cyclodimerization of two isocyanate groups; polyisocyanates having an isocyanurate group or an iminooxadiazinedione group obtained by cyclotrimerization of three isocyanate groups; polyisocyanates having a biuret group obtained by reacting three isocyanate groups with one molecule of water; and the like.

[0057] One type of polyisocyanate may be used, or two or more types may be used in combination. There is no restriction on the type of polyisocyanate, and for example, the type can be selected according to the properties to be imparted to the polyurethane resin (A). From the viewpoint of suppressing yellowing of the resulting polyurethane, aliphatic diisocyanates or alicyclic diisocyanates are preferred, and alicyclic diisocyanates are more preferred.

[0058] - Polyol - The polyphenylene ether polyurethane resin (A1) may contain a polyol other than the polyphenylene ether polyol as a polymerization component. In the present disclosure, a polyol other than the polyphenylene ether polyol is also referred to as a "second polyol".

[0059] There is no limitation on the purpose for which the polyphenylene ether polyurethane resin (A1) contains a second polyol as a polymerization component. For example, since the polyphenylene ether moiety derived from the polyphenylene ether polyol has a relatively rigid structure, flexibility can be imparted to the polyphenylene ether polyurethane resin (A1) by including the second polyol as a polymerization component.

[0060] There is no limitation on the type of the second polyol, and for example, the type can be selected according to the properties to be imparted to the polyphenylene ether polyurethane resin (A1). The second polyol may be any of diols, triols, tetraols, etc., and a diol is preferable in an example of the embodiment. The second polyol may be used alone or in combination of two or more.

[0061] When the polyphenylene ether polyurethane resin (A1) contains a second polyol as a polymerization component, there is no limitation on the polymerization amount of the second polyol, and the polymerization amount can be selected according to the purpose of including the second polyol as a polymerization component or the properties to be imparted to the polyphenylene ether polyurethane resin (A1).

[0062] In an example of the embodiment of the polyphenylene ether polyurethane resin (A1), it is preferable to contain 1 to 120 parts by mass, more preferably 10 to 100 parts by mass, and even more preferably 20 to 80 parts by mass of the second polyol with respect to 100 parts by mass of the polyphenylene ether polyol as a polymerization component.

[0063] Examples of the second polyol include polyester polyol, polycarbonate polyol, polyolefin polyol, and polyether polyol (excluding polyphenylene ether polyol).

[0064] · Polyester polyol Examples of the polyester polyol include an esterified product of a polyvalent carboxylic acid and a polyhydric alcohol; a transesterification product of an alkyl ester of a polyvalent carboxylic acid and a polyhydric alcohol; a polyester polyol obtained by ring-opening polymerization of lactones such as polycaprolactone and polyvalerolactone; and the like.

[0065] Examples of the polyvalent carboxylic acid and the alkyl ester of the polyvalent carboxylic acid include aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, fumaric acid, and maleic acid; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, 2,2'-biphenyldicarboxylic acid, and 4,4'-biphenyldicarboxylic acid; trivalent or higher polyvalent carboxylic acids such as trimellitic acid and pyromellitic acid; carboxylic acid anhydrides such as succinic anhydride, maleic anhydride, phthalic anhydride, and trimellitic anhydride; carboxylic acid halides such as adipic acid dichloride; alkyl esters of carboxylic acids such as dimethyl succinate and dimethyl phthalate; and the like. The polyvalent carboxylic acid may be used alone or in combination of two or more.

[0066] Examples of the polyhydric alcohol include ethylene glycol, 1,3-propanediol, propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,5-pe Dihydric alcohols such as neopentyl glycol, 1,6 - hexanediol, 3 - methyl - 1,5 - pentanediol, 1,4 - cyclohexanedimethanol, 3,3’ - dimethylolheptane, diethylene glycol, 1,4 - bis(hydroxymethyl)cyclohexane, 1,4 - bis(hydroxyethyl)benzene, 2,2 - bis(4,4’ - hydroxycyclohexyl)propane; Trihydric alcohols such as glycerin, trimethylolethane, trimethylolpropane, 1,2,6 - hexanetriol; Tetrahydric to octahydric alcohols such as pentaerythritol, diglycerin, α - methylglucoside, sorbitol, xylitol, mannitol, dipentaerythritol, glucose, fructose, sucrose, etc. The polyhydric alcohol may be used alone or in combination of two or more.

[0067] · Polycarbonate polyol Examples of the polycarbonate polyol include those obtained by a dealcoholization reaction or a dephenolization reaction of a carbonate compound and a polyhydric alcohol.

[0068] Examples of the carbonate compound include alkylene carbonate, dialkyl carbonate, and diaryl carbonate. Examples of the alkylene carbonate include ethylene carbonate, trimethylene carbonate, 1,2 - propylene carbonate, 1,2 - butylene carbonate, 1,3 - butylene carbonate, 1,2 - pentylene carbonate, etc. Examples of the dialkyl carbonate include dimethyl carbonate, diethyl carbonate, dipropyl carbonate, etc. Examples of the diaryl carbonate include diphenyl carbonate, etc. The carbonate compound may be used alone or in combination of two or more.

[0069] Examples of the polyhydric alcohol include the aforementioned polyhydric alcohols related to polyester polyol. The polyhydric alcohol may be used alone or in combination of two or more.

[0070] · Polyolefin polyol Examples of polyolefin polyols include polybutadiene polyols (for example, diols with hydroxy groups introduced at both ends of the polybutadiene molecule), hydrogenated polybutadiene polyols (for example, diols with hydroxy groups introduced at both ends of the hydrogenated polybutadiene molecule), polyisoprene polyols (for example, diols with hydroxy groups introduced at both ends of the polyisoprene molecule), hydrogenated polyisoprene polyols (for example, diols with hydroxy groups introduced at both ends of the hydrogenated polyisoprene molecule), and the like.

[0071] · Polyether polyol Examples of polyether polyols (excluding polyphenylene ether polyols) include aliphatic polyether diols. Examples of aliphatic polyether diols include polyalkylene ether glycols such as polyethylene glycol, polypropylene glycol, polybutylene glycol, and polytetramethylene ether glycol.

[0072] The second polyol is preferably a high molecular weight polyol. In the present disclosure, the high molecular weight polyol means a polyol having a number average molecular weight (Mn) of 600 or more. In an example of the embodiment, the Mn of the second polyol is preferably from 600 to 30,000, more preferably from 800 to 10,000, and even more preferably from 1,000 to 5,000.

[0073] - Diol having a functional group capable of reacting with an epoxy group The polyphenylene ether polyurethane resin (A1) may contain a diol having a functional group capable of reacting with an epoxy group as a polymerization component. The diol is preferably a low-molecular-weight diol. In the present disclosure, the low-molecular-weight diol among the diols having a functional group capable of reacting with an epoxy group means a diol having a number average molecular weight (Mn) of 500 or less. Among the diols having a functional group capable of reacting with an epoxy group, the low-molecular-weight diol preferably has an Mn of 400 or less, more preferably an Mn of 300 or less. Among the diols having a functional group capable of reacting with an epoxy group, the low-molecular-weight diol preferably has an Mn of 100 or more.

[0074] By containing a diol having a functional group capable of reacting with an epoxy group as a polymerization component, the polyphenylene ether polyurethane resin (A1) has the functional group in the molecule. The polyphenylene ether polyurethane resin (A1) may have the functional group at the terminal of the molecule or may have the functional group at a non-terminal of the molecule.

[0075] An example of an embodiment of the polyphenylene ether polyurethane resin (A1) contains a diol having a functional group capable of reacting with an epoxy group as a polymerization component and has a functional group capable of reacting with an epoxy group as a side chain. The polyphenylene ether polyurethane resin (A1) of this embodiment can form a crosslinked structure when reacting with an epoxy resin (D).

[0076] There is no limitation on the type and number of the functional groups of the diol having a functional group capable of reacting with an epoxy group. As the diol having a functional group capable of reacting with an epoxy group, one type may be used, or two or more types may be used in combination.

[0077] Examples of the diol having a functional group capable of reacting with an epoxy group include a diol having at least one carboxy group. An example of an embodiment of the polyphenylene ether polyurethane resin (A1) contains a diol having a carboxy group as a polymerization component and has a carboxy group as a side chain. Examples of the diol having a carboxy group include diols having one carboxy group such as 2,2-bis(hydroxymethyl)propionic acid and 2,2-bis(hydroxymethyl)butanoic acid.

[0078] Examples of the diol having a functional group capable of reacting with an epoxy group include diols having at least one amino group. An example of an embodiment of the polyphenylene ether polyurethane resin (A1) contains a diol having an amino group as a polymerization component and has an amino group as a side chain. Examples of the diol having an amino group include 2-amino-1,3-propanediol and the like.

[0079] When the polyphenylene ether polyurethane resin (A1) contains a diol having a functional group capable of reacting with an epoxy group as a polymerization component, there is no limitation on the polymerization amount of the diol. An example of an embodiment of the polyphenylene ether polyurethane resin (A1) preferably contains 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, and even more preferably 1 to 5 parts by mass of a diol having a functional group capable of reacting with an epoxy group with respect to 100 parts by mass of the polyphenylene ether polyol as a polymerization component.

[0080] An example of an embodiment of the polyphenylene ether polyurethane resin (A1) preferably contains 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 5 parts by mass of a diol having a carboxy group with respect to 100 parts by mass of the polyphenylene ether polyol as a polymerization component.

[0081] An example of an embodiment of the polyphenylene ether polyurethane resin (A1) preferably contains 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 5 parts by mass of a diol having an amino group with respect to 100 parts by mass of the polyphenylene ether polyol as a polymerization component.

[0082] -Chain extender- The polyphenylene ether polyurethane resin (A1) may contain a chain extender as a polymerization component. There is no restriction on the type of the chain extender, and for example, known chain extenders for polyurethanes can be used. One type of chain extender may be used, or two or more types may be used in combination.

[0083] When the polyphenylene ether polyurethane resin (A1) contains a chain extender as a polymerization component, the chain extender is preferably a compound having no functional group other than a hydroxy group, more preferably a polyhydric alcohol having no functional group other than a hydroxy group, and even more preferably a diol having no functional group other than a hydroxy group.

[0084] The compound, polyhydric alcohol, and diol having no functional group other than a hydroxy group as the chain extender are each preferably a low-molecular compound, a low-molecular polyhydric alcohol, and a low-molecular diol. In the present disclosure, the low-molecular compound, low-molecular polyhydric alcohol, and low-molecular diol related to the chain extender each mean a compound, polyhydric alcohol, and diol having a number average molecular weight (Mn) of 500 or less. The low-molecular compound, low-molecular polyhydric alcohol, and low-molecular diol related to the chain extender are each preferably a compound, polyhydric alcohol, and diol having an Mn of 400 or less, and more preferably a compound, polyhydric alcohol, and diol having an Mn of 300 or less. The low-molecular compound, low-molecular polyhydric alcohol, and low-molecular diol related to the chain extender each preferably have an Mn of 50 or more.

[0085] Examples of the chain extender include diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-bis(2-hydroxyethoxy)benzene; triols such as glycerin, trimethylolethane, trimethylolpropane, 1,2,6-hexanetriol; and the like.

[0086] There is no limitation on the purpose for which the polyphenylene ether polyurethane resin (A1) contains a chain extender as a polymerization component. Examples of such purposes include imparting properties according to the use of the resin composition of the present disclosure to the polyphenylene ether polyurethane resin (A1), introducing side chains into the polyphenylene ether polyurethane resin (A1), and the like. For example, by using a diol having an alkyl group branched from the main chain (the main chain here means the carbon chain connecting two hydroxy groups in the diol) as a chain extender, an alkyl group can be introduced as a side chain into the polyurethane resin (A).

[0087] When the polyphenylene ether polyurethane resin (A1) contains a chain extender as a polymerization component, there is no limitation on the polymerization amount of the chain extender, and the polymerization amount can be selected according to the purpose of containing the chain extender as a polymerization component or the properties to be imparted to the polyphenylene ether polyurethane resin (A1).

[0088] An example of an embodiment of the polyphenylene ether polyurethane resin (A1) preferably contains 1 to 30 parts by mass, more preferably 3 to 25 parts by mass, and even more preferably 5 to 20 parts by mass of a chain extender with respect to 100 parts by mass of the polyphenylene ether polyol as a polymerization component.

[0089] - Physical properties of the polyphenylene ether polyurethane resin (A1)- From the viewpoint of heat resistance, the glass transition temperature (Tg) of the polyphenylene ether polyurethane resin (A1) is preferably 100°C or higher, more preferably 110°C or higher, and even more preferably 120°C or higher. The Tg of the polyphenylene ether polyurethane resin (A1) is usually 200°C or lower.

[0090] In the present disclosure, the glass transition temperature (Tg) of the polyurethane resin is determined by dynamic viscoelasticity measurement. Using a dried film of the polyurethane resin as a test piece, the dynamic viscoelasticity of the test piece is measured in tension mode under the conditions of a heating rate of 2 °C / min and a frequency of 1 Hz, and the maximum value of the loss tangent of the obtained curve is taken as the glass transition temperature (Tg).

[0091] From the viewpoint of processability, the weight average molecular weight (Mw) of the polyphenylene ether polyurethane resin (A1) is preferably 30,000 or more, more preferably 50,000 or more, and even more preferably 70,000 or more. From the viewpoint of solubility in organic solvents, the Mw of the polyphenylene ether polyurethane resin (A1) is preferably 200,000 or less.

[0092] From the viewpoint of processability, the number average molecular weight (Mn) of the polyphenylene ether polyurethane resin (A1) is preferably 5,000 or more, more preferably 8,000 or more, and even more preferably 10,000 or more. From the viewpoint of solubility in organic solvents, the Mn of the polyphenylene ether polyurethane resin (A1) is preferably 40,000 or less.

[0093] From the viewpoint of solubility in organic solvents, the acid value (mgKOH / g) of the polyphenylene ether polyurethane resin (A1) is preferably from 0 mgKOH / g to 30 mgKOH / g, more preferably from 1 mgKOH / g to 20 mgKOH / g, and even more preferably from 2 mgKOH / g to 10 mgKOH / g.

[0094] In the present disclosure, the acid value (mgKOH / g) of the polyurethane resin is determined by neutralization titration of the sample with a potassium hydroxide benzyl alcohol solution using a phenolphthalein solution as an indicator.

[0095] - Method for producing polyphenylene ether polyurethane resin (A1)- There is no limitation on the method for producing the polyphenylene ether polyurethane resin (A1), and a known production method for producing a polyurethane resin may be adopted. The polyphenylene ether polyol, the polyisocyanate, and other polymerization components selected as necessary may be charged into the reaction vessel all at once or separately. Examples of the reaction vessel include a reaction kettle equipped with a stirring device, a kneader, and a twin-screw kneading extruder.

[0096] The production of the polyphenylene ether polyurethane resin (A1) can be carried out in the presence or absence of a solvent inert to isocyanate groups. Examples of such solvents include ester solvents (ethyl acetate, butyl acetate, ethyl butyrate, etc.), ether solvents (dioxane, tetrahydrofuran, diethyl ether, etc.), ketone solvents (cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, etc.), aromatic hydrocarbon solvents (benzene, toluene, xylene, etc.), and mixed solvents thereof.

[0097] In the production of the polyphenylene ether polyurethane resin (A1), a known catalyst for the urethane reaction may be used. Examples of the catalyst for the urethane reaction include tin-based catalysts (dibutyltin dilaurate, trimethyltin hydroxide, stannous octoate, etc.), lead-based catalysts, amine-based catalysts, and the like.

[0098] In the production of the polyphenylene ether polyurethane resin (A1), the total number ratio of isocyanate groups to hydroxy groups of all polymerization components (isocyanate group / hydroxy group) is preferably 0.9 or more and 1.1 or less, more preferably 0.95 or more and 1.05 or less, and even more preferably 0.98 or more and 1.02 or less.

[0099] The resin composition of the present disclosure may contain one kind or two or more kinds of the polyphenylene ether polyurethane resin (A1).

[0100] The amount of the polyphenylene ether polyurethane resin (A1) in the total solid content excluding the filler of the resin composition of the present disclosure is preferably 50% by mass to 90% by mass, more preferably 55% by mass to 85% by mass, and even more preferably 60% by mass to 80% by mass from the viewpoints of the moisture and heat resistance, heat resistance, and adhesive strength of the resin composition and the cured product.

[0101] [Polyester polyurethane resin (A2)] In the present disclosure, the polyester polyurethane resin (A2) may be a resin having two or more ester bonds and two or more urethane bonds, but is preferably a resin having a polyester chain and two or more urethane bonds. Further, the polyester polyurethane resin (A2) is preferably a resin obtained by reacting at least a polyester polyol, a polyisocyanate, and a chain extender, and more preferably a resin obtained by reacting at least a polyester polyol, a polyisocyanate, and a diol compound as the chain extender.

[0102] The polyester portion in the polyester polyurethane resin (A2) is preferably formed from an acid component and an alcohol component. As the acid component, a polycarboxylic acid compound is preferable, and a dicarboxylic acid compound is more preferable. Further, a sulfocarboxylic acid compound or the like can also be used as the acid component. Furthermore, an aromatic acid is preferably mentioned as the acid component. As the alcohol component, a polyhydric alcohol compound is preferable, and a diol compound is more preferable. Also, the polyester portion may be formed by a hydroxycarboxylic acid compound.

[0103] When the total amount of all acid components constituting the polyester portion of the polyester polyurethane resin (A2) is 100 mol%, from the viewpoints of adhesiveness, heat resistance, and moisture and heat resistance, among the all acid components, the aromatic acid is preferably 30 mol% or more, more preferably 45 mol% or more, and particularly preferably 60 mol% or more.

[0104] Examples of aromatic acids include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, biphenyldicarboxylic acid, 5-hydroxyisophthalic acid, etc. Further, sulfonated terephthalic acid, 5-sulfoisophthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5-(4-sulfophenoxy)isophthalic acid, sulfonated terephthalic acid, and / or aromatic dicarboxylic acids having a sulfonic acid group or a sulfonate group such as their metal salts and ammonium salts, aromatic oxycarboxylic acids such as p-hydroxybenzoic acid, p-hydroxyphenylpropionic acid, p-hydroxyphenylacetic acid, 6-hydroxy-2-naphthoic acid, 4,4-bis(p-hydroxyphenyl)valeric acid, etc. can be mentioned. Among these, from the viewpoint of adhesiveness, as the acid component, it is preferably to contain terephthalic acid and / or isophthalic acid, and particularly preferably terephthalic acid and / or isophthalic acid.

[0105] Further, the acid component may be a derivative of an acid compound such as an ester during resin synthesis. Also, other acid components include alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid and its acid anhydride, and aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, etc.

[0106] On the one hand, examples of the polyhydric alcohol component preferably include aliphatic diol compounds, alicyclic diol compounds, aromatic-containing diol compounds, ether bond-containing diol compounds, etc. Examples of the aliphatic diol compounds include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-butyl-2-ethyl-1,3-propanediol, neopentyl glycol hydroxypivalate, dimethylolheptane, 2,2,4-trimethyl-1,3-pentanediol, etc. Examples of the alicyclic diol compounds include 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, tricyclodecanediol, tricyclodecanedimethylol, spiroglycol, hydrogenated bisphenol A, ethylene oxide adducts and propylene oxide adducts of hydrogenated bisphenol A, etc. Examples of the aromatic-containing diol compounds include glycols obtained by adding 1 to several moles of ethylene oxide or propylene oxide to each of the two phenolic hydroxyl groups of bisphenols such as paraxylene glycol, metaxylene glycol, orthoxylene glycol, 1,4-phenylene glycol, ethylene oxide adduct of 1,4-phenylene glycol, bisphenol A, ethylene oxide adducts and propylene oxide adducts of bisphenol A, etc. Examples of the ether bond-containing diol compounds include diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene oxide adduct of neopentyl glycol, propylene oxide adduct of neopentyl glycol, etc.

[0107] Among these diols, diols having side chains such as neopentyl glycol and 2-butyl-2-ethyl-1,3-propanediol are preferred for reasons of compatibility with epoxy resins and solution stability. That is, the diol component constituting the polyester polyurethane resin (A2) preferably contains a diol having a side chain from the viewpoints of compatibility with epoxy resins and solution stability. Among them, from the viewpoints of compatibility with epoxy resins, solution stability, and conductivity, it is more preferable that the chain extender constituting the polyester polyurethane resin (A2) contains a diol having a side chain. That is, the polyester polyurethane resin (A2) is more preferably a resin obtained by reacting at least a polyester polyol, a polyisocyanate, and a diol having a side chain as raw materials from the viewpoints of compatibility with epoxy resins, solution stability, and conductivity.

[0108] In addition, hydroxycarboxylic acid compounds having a hydroxy group and a carboxy group in their molecular structures can also be used as polyester raw materials, and examples thereof include 5-hydroxyisophthalic acid, p-hydroxybenzoic acid, p-hydroxyphenethyl alcohol, p-hydroxyphenylpropionic acid, p-hydroxyphenylacetic acid, 6-hydroxy-2-naphthoic acid, 4,4-bis(p-hydroxyphenyl)valeric acid, and the like.

[0109] As a component constituting the polyester part of the polyester polyurethane resin (A2), for the purpose of introducing a branched skeleton if necessary, trifunctional or higher polycarboxylic acids and / or polyols in an amount of about 0.1 mol% to 5 mol% may be copolymerized with respect to all acid components or all polyhydric alcohol components constituting the polyester part. In particular, when a cured layer is obtained by reacting with a curing agent, by introducing a branched skeleton, a cured layer with an increased terminal group concentration (reaction point) of the resin and a high crosslink density can be obtained. Examples of trifunctional or higher polycarboxylic acids in that case include compounds such as trimellitic acid, trimesic acid, ethylene glycol bis(anhydrotrimellitate), glycerol tris(anhydrotrimellitate), trimellitic anhydride, pyromellitic anhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA), 3,3',4,4'-diphenyltetracarboxylic dianhydride (BPDA), 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride (DSDA), 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA), 2,2'-bis[(dicarboxyphenoxy)phenyl]propane dianhydride (BSAA). On the other hand, examples of trifunctional or higher polyols include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, etc. When using trifunctional or higher polycarboxylic acids and / or polyols, it is preferably copolymerized in the range of 0.1 mol% to 5 mol%, more preferably 0.1 mol% to 3 mol% with respect to all acid components or all polyhydric alcohol components.

[0110] For the polyester portion of the polyester polyurethane resin (A2), for the purpose of introducing a carboxy group if necessary, acid addition can be carried out to the extent of 0.1 mol% to 10 mol% with respect to all acid components or all polyhydric alcohol components constituting the polyester portion. When a monocarboxylic acid, dicarboxylic acid, or polyfunctional carboxylic acid compound is used for acid addition, the molecular weight decreases due to transesterification, so it is preferable to use an acid anhydride. Examples of the acid anhydride include compounds such as succinic anhydride, maleic anhydride, phthalic anhydride, 2,5-norbornene dicarboxylic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3’,4,4’-benzophenone tetracarboxylic dianhydride (BTDA), 3,3’,4,4’-diphenyltetracarboxylic dianhydride (BPDA), 3,3’,4,4’-diphenylsulfone tetracarboxylic dianhydride (DSDA), 4,4’-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA), and 2,2’-bis[(dicarboxyphenoxy)phenyl]propane dianhydride (BSAA). The acid addition can be carried out by a method of directly performing it in a bulk state after polyester polycondensation and a method of adding it after dissolving the polyester. The reaction in the bulk state is fast, but gelation may occur when a large amount of acid addition is carried out, and since it is a reaction at a high temperature, precautions such as blocking oxygen gas to prevent oxidation are necessary. On the other hand, the acid addition in the solution state is slow, but a large amount of carboxy groups can be stably introduced.

[0111] The polyisocyanate used in the production of the polyester polyurethane resin (A2) is not particularly limited, and the polyisocyanates described in the description of the polyphenylene ether polyurethane resin (A1) can be appropriately used. Alternatively, the polyisocyanate may be one kind of diisocyanate, its dimer (uretdione), its trimer (isocyanurate, triol adduct, biuret), etc., or a mixture of two or more of them. For example, as the diisocyanate component, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-phenylene diisocyanate, diphenylmethane diisocyanate, m-phenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, 4,4'-diisocyanate diphenyl ether, m-xylylene diisocyanate, 1,3-diisocyanate methylcyclohexane, 1,4-diisocyanate methylcyclohexane, 4,4'-diisocyanate cyclohexane, 4,4'-diisocyanate cyclohexylmethane, isophorone diisocyanate, dimer acid diisocyanate, norbornene diisocyanate, etc. can be mentioned. Among them, from the viewpoint of transparency, aliphatic or alicyclic diisocyanates are preferred. Further, for reasons of easy availability and economy, hexamethylene diisocyanate and isophorone diisocyanate are particularly preferred.

[0112] In the production of the polyester polyurethane resin (A2), a chain extender may be used if necessary. Examples of the chain extender include the diol compounds already described as components of the polyester moiety, and compounds having one carboxy group and two hydroxy groups such as dimethylolpropionic acid and dimethylolbutanoic acid. Among them, from the viewpoint of conductivity, the chain extender is preferably a diol compound, more preferably a diol compound having a side chain, and particularly preferably a diol compound having a branched chain. From the viewpoint of conductivity, the diol compound having a side chain preferably contains at least one compound selected from the group consisting of neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, and dimethylolpropionic acid, and particularly preferably contains at least one compound selected from the group consisting of neopentyl glycol and 2-butyl-2-ethyl-1,3-propanediol and dimethylolpropionic acid.

[0113] The method for producing the polyester polyurethane resin (A2) is not particularly limited, and known methods can be used. For example, the polyester polyol, polyisocyanate, and, if necessary, the chain extender may be charged into the reaction vessel all at once or separately. In any case, regarding the total hydroxyl value of the polyester polyol and chain extender in the system and the total isocyanate groups of the polyisocyanate, the functional group ratio of isocyanate group / hydroxyl group is preferably reacted at 0.9 or more and 1.1 or less, more preferably 0.98 or more and 1.02 or less, and particularly preferably 1. Further, this reaction can be produced by reacting in the presence or absence of a solvent inert to isocyanate groups. Examples of the solvent include ester solvents (such as ethyl acetate, butyl acetate, and ethyl butyrate), ether solvents (such as dioxane, tetrahydrofuran, and diethyl ether), ketone solvents (such as cyclohexanone, methyl ethyl ketone, and methyl isobutyl ketone), aromatic hydrocarbon solvents (such as benzene, toluene, and xylene), and mixed solvents thereof. From the viewpoint of reducing environmental load, ethyl acetate and methyl ethyl ketone are preferred. The reaction apparatus is not limited to a reaction vessel equipped with a stirring device, and mixing and kneading devices such as a kneader and a twin-screw extruder can also be used.

[0114] To promote the urethane reaction, catalysts used in ordinary urethane reactions, such as tin-based catalysts (such as trimethyltin laurate, dimethyltin dilaurate, trimethyltin hydroxide, dimethyltin dihydroxide, and stannous octoate), lead-based catalysts (such as red lead and red-2-ethylhexoate), and amine-based catalysts (such as triethylamine, tributylamine, morpholine, diazabicyclooctane, and diazabicycloundecene), etc. can be used.

[0115] The glass transition temperature (Tg) of the polyester portion in the polyester polyurethane resin (A2) is preferably from 40°C to 150°C, more preferably from 45°C to 120°C, still more preferably from 50°C to 90°C, and particularly preferably from 60°C to 70°C, from the viewpoints of adhesiveness, conductivity, and heat resistance. Further, the glass transition temperature (Tg) of the polyester polyurethane resin (A2) is preferably from 30°C to 150°C, more preferably from 40°C to 140°C, and particularly preferably from 50°C to 120°C, from the viewpoints of adhesiveness, conductivity, and heat resistance.

[0116] From the viewpoint of processability, the polyester polyurethane resin (A2) preferably has a weight average molecular weight (Mw) of 30,000 or more, more preferably 50,000 or more, and still more preferably 70,000 or more. From the viewpoint of solubility in an organic solvent, the Mw of the polyester polyurethane resin (A2) is preferably 200,000 or less.

[0117] From the viewpoints of adhesiveness and conductivity, the acid value of the polyester polyurethane resin (A2) is preferably from 0 mgKOH / g to 50 mgKOH / g, more preferably from 0.1 mgKOH / g to 20 mgKOH / g, and particularly preferably from 0.1 mgKOH / g to 5 mgKOH / g. Further, from the viewpoint of heat resistance, the acid value of the polyester polyurethane resin (A2) is preferably 20 mg / KOH / g or less, and particularly preferably 5 mgKOH / g or less.

[0118] In the present disclosure, the acid value (mgKOH / g) of the polyurethane resin is determined by neutralization titration of a sample with a potassium hydroxide benzyl alcohol solution using a phenolphthalein solution as an indicator.

[0119] The resin composition of the present disclosure may contain the polyester polyurethane resin (A2) alone or in combination of two or more. From the viewpoints of adhesiveness, conductivity, and heat resistance, the content of the polyester polyurethane resin (A2) is preferably 5% by mass to 90% by mass, more preferably 10% by mass to 80% by mass, still more preferably 20% by mass to 75% by mass, and particularly preferably 30% by mass to 70% based on the total solid content of the resin composition.

[0120] [Polyolefin resin (B)] In the resin composition of the present disclosure, the polyolefin resin (B) is a polyolefin resin having a functional group capable of reacting with the epoxy resin (D), and for example, it can be a modified polyolefin resin (hereinafter referred to as the modified polyolefin resin (B)). The modified polyolefin resin (B) is a resin having a part derived from a polyolefin resin and a graft part derived from a modifier, and is preferably a resin soluble in a solvent described later.

[0121] The modified polyolefin resin (B) is preferably a polyolefin resin obtained by graft-modifying an unmodified polyolefin resin with a modifier containing an α,β-unsaturated carboxylic acid or a derivative thereof. The production by graft modification of the modified polyolefin resin (B) can be carried out by a known method, and a radical initiator may be used during the production. Specific production methods of the modified polyolefin resin (B) include, for example, a solution method in which an unmodified polyolefin resin is heated and dissolved in a solvent such as toluene, and a modifier and a radical initiator are added, and a melting method in which a polyolefin resin, a modifier, and a radical initiator are melt-kneaded using a Banbury mixer, a kneader, an extruder, etc. In the case of the melting method, the usage methods of the polyolefin resin, the modifier, and the radical initiator are not particularly limited, and these may be added to the reaction system all at once or sequentially.

[0122] When producing the modified polyolefin resin (B), a modifier aid for improving the graft efficiency of a modifier containing an α,β-unsaturated carboxylic acid or its derivative, a stabilizer for adjusting the stability of the resin, etc. can be further used.

[0123] The polyolefin resin used for graft polymerization is not particularly limited as long as it has a structural unit derived from an olefin. As the above polyolefin resin, a homopolymer or copolymer of an olefin having 2 to 20 carbon atoms such as ethylene, propylene, butene, pentene, hexene, heptene, octene, 4-methyl-1-pentene is preferably used. In the present disclosure, a homopolymer or copolymer of an olefin having 2 to 6 carbon atoms is particularly preferred. The content ratio of the structural unit derived from an olefin in the polyolefin resin can be arbitrarily selected. Note that the polyolefin resin used for graft polymerization may be either a modified polyolefin resin or an unmodified polyolefin resin.

[0124] In particular, the modified polyolefin resin (B) is preferably a modified product of an unmodified polyolefin resin, and more preferably contains a modified resin of an ethylene-propylene copolymer, a propylene-butene copolymer or an ethylene-propylene-butene copolymer, that is, a modified polypropylene resin. Thereby, a resin composition suitable for adhesion to a difficult-to-adhere adherend can be obtained. In this case, the resin composition preferably contains a modified polypropylene resin obtained by using a polyolefin resin having a propylene unit content ratio of 50 mol% or more. Thereby, the adhesiveness in the resin composition becomes further excellent.

[0125] The modifier contains at least one selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives. Examples of the α,β-unsaturated carboxylic acid include maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, aconitic acid, norbornenedicarboxylic acid, and the like. Examples of the derivative of the α,β-unsaturated polycarboxylic acid include acid anhydrides, acid halides, amides, imides, esters, and the like of these acids. As the above-mentioned modifier, at least one selected from the group consisting of itaconic anhydride, maleic anhydride, aconitic anhydride, and citraconic anhydride is preferable, and itaconic anhydride or maleic anhydride is particularly preferable in terms of adhesiveness. When using a modifier, it may be at least one or more selected from the group consisting of α,β-unsaturated carboxylic acids and their derivatives, and may be a combination of one or more α,β-unsaturated carboxylic acids and one or more of their derivatives, a combination of two or more α,β-unsaturated carboxylic acids, or a combination of two or more derivatives of α,β-unsaturated carboxylic acids.

[0126] In the present disclosure, the modifier can contain other compounds (other modifiers) in addition to α,β-unsaturated carboxylic acids, etc., according to the purpose. Examples of the other compounds (other modifiers) include acrylic acid or methacrylic acid (hereinafter, "acrylic" and / or "methacrylic" are referred to as "(meth)acrylic"), derivatives of (meth)acrylic acid, aromatic vinyl compounds, cyclohexyl vinyl ether, and the like. These other compounds may be used alone or in combination of two or more.

[0127] As the above-mentioned derivative of (meth)acrylic acid, the (meth)acrylic acid ester represented by the following formula (4) can be used.

[0128] CH2=CR 1 COOR 2 (4) (In the formula, R 1 is a hydrogen atom or a methyl group, and R 2 is a hydrocarbon group.)

[0129] In the above formula (4), R1 is a hydrogen atom or a methyl group, preferably a methyl group. R 2 is a hydrocarbon group, preferably an alkyl group having 8 to 18 carbon atoms, a cycloalkyl group having 8 to 18 carbon atoms, or an aryl group having 8 to 18 carbon atoms.

[0130] Examples of the compound represented by the above formula (4) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, and the like. These compounds may be used alone or in combination of two or more. In the present disclosure, since the heat-resistant adhesiveness is improved, other modifiers preferably include a (meth)acrylate ester having an alkyl group having 8 to 18 carbon atoms. As the (meth)acrylate ester having an alkyl group having 8 to 18 carbon atoms, at least one selected from the group consisting of octyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, and stearyl (meth)acrylate is particularly preferable.

[0131] Examples of (meth)acrylic acid derivatives other than (meth)acrylate esters include hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, isocyanate group-containing (meth)acrylic acid, and the like.

[0132] Examples of the above aromatic vinyl compound include styrene, o-methylstyrene, p-methylstyrene, α-methylstyrene, and the like.

[0133] By using an α,β-unsaturated carboxylic acid or its derivative and another modifier in combination as the above-mentioned modifier, the graft ratio by the modifier can be improved, the solubility of the obtained modified polyolefin resin (B) in a solvent can be improved, or the adhesiveness of the adhesive composition containing this modified polyolefin resin (B) can be further improved.

[0134] As described above, the modified polyolefin resin (B) has at least a graft portion derived from the modifier. Hereinafter, the content ratio of the graft portion contained in the modified polyolefin resin (B) (hereinafter, also referred to as "graft mass") will be described.

[0135] The above-mentioned modified polyolefin resin (B) has a graft portion derived from an α,β-unsaturated carboxylic acid or its derivative. In the above-mentioned modified polyolefin resin (B), from the viewpoint of improving the adhesiveness when used as an adhesive composition, the graft mass of the graft portion derived from an α,β-unsaturated carboxylic acid or its derivative is preferably 0.1% by mass to 20% by mass, more preferably 0.2% by mass to 18% by mass, based on 100% by mass of the modified polyolefin resin (B). When the graft mass is 0.1% by mass or more, the modified polyolefin resin (B) has excellent solubility in a solvent and particularly excellent adhesiveness to an adherend made of metal or the like. Also, when the graft mass is 20% by mass or less, it has particularly excellent adhesiveness to an adherend made of resin or the like.

[0136] The graft mass of the graft portion derived from an α,β-unsaturated carboxylic acid or its derivative in the above-mentioned modified polyolefin resin (B) can be determined by an alkali titration method. However, when the derivative of the α,β-unsaturated carboxylic acid is an imide or the like having no acid group, the graft mass can be determined by Fourier transform infrared spectroscopy.

[0137] When the modified polyolefin resin (B) contains a graft portion derived from the (meth)acrylate represented by the above formula (4), which is another modifier, the graft mass is preferably 0.1% by mass to 30% by mass, more preferably 0.3% by mass to 25% by mass, based on 100% by mass of the modified polyolefin resin (B). When the graft mass of the graft portion derived from the (meth)acrylate is 0.1% by mass to 30% by mass, the solubility of the modified polyolefin resin (B) in a solvent is excellent, and when it is used as an adhesive composition and the adhesive composition contains other resins or elastomers, the compatibility with these is excellent, and the adhesiveness to the adherend can be further improved.

[0138] When the graft portion contains a graft portion derived from the (meth)acrylate represented by the above formula (4), the graft mass of the graft portion in the obtained modified polyolefin resin (B) can be determined by Fourier transform infrared spectroscopy.

[0139] When the modified polyolefin resin (B) is produced using a radical initiator, the radical initiator can be appropriately selected from known ones. As the radical initiator, for example, it is preferable to use organic peroxides such as benzoyl peroxide, dicumyl peroxide, lauroyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, and cumene hydroperoxide.

[0140] When producing the modified polyolefin resin (B), a modification aid, a stabilizer, etc. can be used. Examples of the modification aid include divinylbenzene, hexadiene, dicyclopentadiene, etc. Examples of the stabilizer include hydroquinone, benzoquinone, nitrosophenylhydroxy compounds, etc.

[0141] From the perspective of processability, the weight average molecular weight (Mw) of the above-mentioned modified polyolefin resin (B) is preferably 30,000 or more, more preferably 50,000 or more, and even more preferably 70,000 or more. From the perspective of solubility in organic solvents, the Mw of the modified polyolefin resin (B) is preferably 250,000 or less, and more preferably 200,000 or less.

[0142] The acid value of the above-mentioned modified polyolefin resin (B) is preferably 0.1 mgKOH / g to 50 mgKOH / g, more preferably 0.5 mgKOH / g to 40 mgKOH / g, and even more preferably 1.0 mgKOH / g to 30 mgKOH / g. By setting the acid value within this range, when a resin composition containing the modified polyolefin resin (B) is used as an adhesive, a sufficiently cured adhesive joint can be formed, and good adhesiveness, heat resistance, and resin flow-out properties can be obtained.

[0143] In the present disclosure, the acid value (mgKOH / g) of the modified polyolefin resin (B) is also determined by neutralization titration of a sample with a potassium hydroxide benzyl alcohol solution using a phenolphthalein solution as an indicator.

[0144] In the resin composition of the present disclosure, the content of the above-mentioned modified polyolefin resin (B) is preferably 50% by mass or more, more preferably 60% by mass or more, based on 100% by mass of the solid content (excluding the solvent) of the resin composition. However, the upper limit is preferably 99% by mass. In a resin composition with a content of less than 50% by mass, the flexibility of the adhesive layer formed by the resin composition may not be obtained, and deformation such as warping may occur in the resulting integrated product.

[0145] [Melamine resin (C)] The melamine resin (C) is a resin containing structural units derived from alkylated melamine, and preferably a resin containing structural units derived from methylated melamine. The alkylated melamine from which the structural units of the melamine resin (C) are derived can be represented, for example, by the following formula (5).

[0146]

Chem.

[0147] In formula (5), R 1 ~R 6 may be the same or different and each represents any one selected from the group consisting of a hydrogen atom, a hydroxymethyl group (-CH2OH), and an alkoxymethyl group. However, at least one of R 1 ~R 6 is a hydroxymethyl group or an alkoxymethyl group. Examples of the alkoxymethyl group include a methoxymethyl group (-CH2OCH3), an ethoxymethyl group (-CH2OCH2CH3), an n-butoxymethyl group (-CH2OCH2CH2CH2CH3), and an isobutoxymethyl group (-CH2OCH(CH3)CH2CH3), etc.

[0148] The resin composition of the present disclosure contains a melamine resin (C), and due to the crosslinking reaction between the epoxy resin (D) and the melamine resin (C) described later, and the interaction between the melamine resin (C) and the base material or adherend described later, etc., the occurrence of appearance abnormalities at the place of use can be suppressed even by heating.

[0149] In the present disclosure, the melamine resin (C) may be composed of a fully etherified alkylated melamine in which all of R 1 ~R 6 are alkoxymethyl groups, or may be composed of an imino-type alkylated melamine in which at least one of R 1 ~R 6 is a hydrogen atom, or may be composed of a hydroxymethyl-type alkylated melamine in which at least one of R 1 ~R 6 is a hydroxymethyl group, or may be composed of an iminomethylol-type alkylated melamine in which at least one of R 1 ~R 6 is a hydrogen atom and at least one is a hydroxymethyl group.

[0150] In particular, in the present disclosure, the alkylated melamine derived from the constituent unit of the melamine resin (C) is preferably at least one alkylated melamine selected from the group consisting of imino-type alkylated melamine, methylol-type alkylated melamine, and iminomethylol-type alkylated melamine. When using at least one alkylated melamine selected from the group consisting of these imino-type alkylated melamine, methylol-type alkylated melamine, and iminomethylol-type alkylated melamine, a crosslinking reaction can be formed between the amino group and / or hydroxyl group in the molecule and the epoxy resin (D) described later. Therefore, when the resin composition of the present disclosure is used as an adhesive composition, the occurrence of appearance abnormalities at the used location can be more reliably suppressed even by heating, and the strength of the adhesive part can be maintained.

[0151] The melamine resin (C) may have a structural unit derived from at least one alkylated melamine selected from the group consisting of imino-type alkylated melamine, methylol-type alkylated melamine, and iminomethylol-type alkylated melamine only at the terminal portion. By using the melamine resin (C) having a structural unit derived from at least one alkylated melamine selected from the group consisting of imino-type alkylated melamine, methylol-type alkylated melamine, and iminomethylol-type alkylated melamine only at the terminal portion, the crosslinking reactivity can be improved.

[0152] Furthermore, the melamine resin (C) is not particularly limited, but for example, a melamine resin having a low degree of polymerization of dimer to decamer, more specifically, about dimer to trimer may be used. By using a melamine resin having a low degree of polymerization, the density of reactive functional groups can be increased, and the crosslinking reactivity can be improved.

[0153] As the melamine resin (C), commercially available products such as Nikalac MW-30M, Nikalac MW-30, Nikalac MW-30HM, Nikalac MW-390, Nikalac MW-100LM, Nikalac MX-750LM, Nikalac MW-22, Nikalac MS-21, Nikalac MS-11, Nikalac MW-12LF, Nikalac MW-24X, Nikalac MS-001, Nikalac MX-002, Nikalac MX-730, Nikalac MX-750, Nikalac MX-708, Nikalac MX-706, Nikalac MX-042, Nikalac MX-035, Nikalac MX-45, Nikalac MX-43, Nikalac MX-417, Nikalac MX-410 (manufactured by Sanwa Chemical Co., Ltd.) etc. can be used. In addition, other commercially available products of melamine resin (C) include Cymel 300, Cymel 301, Cymel 303LF, Cymel 350, Cymel 370N, Cymel 771, Cymel 325, Cymel 327, Cymel 703, Cymel 712, Cymel 701, Cymel 266, Cymel 267, Cymel 285, Cymel 232, Cymel 235, Cymel 236, Cymel 238, Cymel 272, Cymel 212, Cymel 253, Cymel 254, Cymel 202, Cymel 207 (manufactured by Ornex Japan Co., Ltd.) etc. As the melamine resin (C), these commercially available products can be used alone or in combination of two or more kinds.

[0154] In addition, as the melamine resin (C), the weight average degree of polymerization is preferably 1.1 to 10, more preferably 1.1 to 6.0, and even more preferably 1.1 to 3.0. More specifically, as the melamine resin (C), Nikalac MX-750 (weight average degree of polymerization: 2.2), which is an iminomethylol type melamine resin, Nikalac MX-730 (weight average degree of polymerization: 2.4), which is an imino type melamine resin, Nikalac MW-12LF (weight average degree of polymerization: 1.7), which is a methylol type melamine resin, and Nikalac MW-30 (weight average degree of polymerization: 1.5), which is a full ether type melamine resin can be used. The weight average degree of polymerization of the melamine resin (C) is determined from the weight average molecular weight (Mw) by the following procedure. First, the weight average molecular weight (Mw) of the melamine resin (C) is measured in terms of polystyrene using a gel permeation chromatography apparatus (GPC apparatus). Next, by dividing by the molecular weight of the constituent unit of the melamine resin (C), the weight average degree of polymerization of the melamine resin (C) can be determined.

[0155] The content of the melamine resin (C) is preferably 0.2 parts by mass to 10 parts by mass, more preferably 0.2 parts by mass to 7 parts by mass, still more preferably 0.2 parts by mass to 5 parts by mass, and even more preferably 0.2 parts by mass to 1 part by mass with respect to 100 parts by mass of the polyurethane resin (A) and / or the polyolefin resin (B). When the content of the melamine resin (C) is within the above range, when the resin composition of the present disclosure is used as an adhesive composition, the occurrence of appearance abnormalities at the use location can be suppressed even by heating, and the strength of the adhesive portion can be maintained. In particular, when the content of the melamine resin (C) is less than the lower limit value of the above range, appearance abnormalities may occur due to heating, and the strength of the adhesive portion may deteriorate. Further, especially when the content of the melamine resin (C) exceeds the upper limit value of the above range, appearance abnormalities or deterioration of the strength of the adhesive portion due to heating are less likely to occur, but the conductivity of the resin composition containing the conductive filler (E) may decrease, and it may not be suitable for use in locations where conductivity is required.

[0156] [Epoxy resin (D)] Epoxy resin (D) is a component that imparts adhesiveness to the resin composition and heat resistance to the cured product of the resin composition.

[0157] Epoxy resin (D) includes a high molecular compound having an epoxy group and a low molecular compound having an epoxy group. It is preferable that the number of epoxy groups in each molecule of epoxy resin (D) is 2 or more.

[0158] Examples of epoxy resin (D) include glycidyl esters such as diglycidyl orthophthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl p-hydroxybenzoate, diglycidyl tetrahydrophthalate, diglycidyl succinate, diglycidyl adipate, diglycidyl sebacate, triglycidyl trimellitate; glycidyl ethers such as diglycidyl ether of bisphenol A and its oligomers, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, tetraphenyl glycidyl ether ethane, triphenyl glycidyl ether ethane, polyglycidyl ether of sorbitol, polyglycidyl ether of polyglycerol; novolak type epoxy resins such as phenol novolak epoxy resin, o-cresol novolak epoxy resin, bisphenol A novolak epoxy resin; and the like.

[0159] Examples of epoxy resin (D) also include brominated bisphenol A type epoxy resin, phosphorus-containing epoxy resin, epoxy resin containing a trisphenol methane skeleton, epoxy resin containing a dicyclopentadiene skeleton, epoxy resin containing a naphthalene skeleton, anthracene type epoxy resin, tertiary butyl catechol type epoxy resin, biphenyl type epoxy resin, bisphenol S type epoxy resin, and the like.

[0160] From the viewpoints of imparting adhesiveness to the resin composition and imparting heat resistance to the cured product of the resin composition, the epoxy resin (D) preferably contains a tris-phenol methane skeleton-containing epoxy resin.

[0161] From the viewpoint of imparting high heat resistance to the cured product of the resin composition, the epoxy resin (D) preferably contains an epoxy resin having 3 or more epoxy groups in one molecule.

[0162] The resin composition of the present disclosure may contain one kind of the epoxy resin (D) or may contain two or more kinds thereof.

[0163] From the viewpoint of imparting adhesiveness to the resin composition, the content of the epoxy resin (D) contained in the resin composition of the present disclosure is preferably 1 part by mass or more, more preferably 5 parts by mass or more, still more preferably 10 parts by mass or more, and still more preferably 15 parts by mass or more with respect to 100 parts by mass in total of the polyurethane resin (A) and / or the polyolefin resin (B).

[0164] From the viewpoints of imparting moisture and heat resistance, heat resistance, and adhesive strength to the resin composition and the cured product, the content of the epoxy resin (D) contained in the resin composition of the present disclosure is preferably 60 parts by mass or less, more preferably 55 parts by mass or less, still more preferably 50 parts by mass or less, and still more preferably 45 parts by mass or less with respect to 100 parts by mass in total of the polyurethane resin (A) and / or the polyolefin resin (B).

[0165] In particular, when the polyphenylene ether polyurethane resin (A1) is included as the polyurethane resin (A), from the viewpoints of imparting moisture and heat resistance, heat resistance, and adhesive strength due to the polyphenylene ether moiety to the resin composition and the cured product, the content of the epoxy resin (D) contained in the resin composition of the present disclosure is preferably 60 parts by mass or less, more preferably 55 parts by mass or less, still more preferably 50 parts by mass or less, and still more preferably 45 parts by mass or less with respect to 100 parts by mass in total of the polyurethane resin (A) and / or the polyolefin resin (B).

[0166] From the perspective of achieving both of the above properties, the resin composition of the present disclosure preferably contains 1 to 60 parts by mass, more preferably 5 to 55 parts by mass, even more preferably 10 to 50 parts by mass, and even more preferably 15 to 45 parts by mass of the epoxy resin (D) with respect to a total of 100 parts by mass of the polyurethane resin (A) and / or the polyolefin resin (B).

[0167] From the perspectives of the moisture and heat resistance, heat resistance, and adhesive strength of the resin composition and the cured product, the total amount of the polyurethane resin (A), polyolefin resin (B), melamine resin (C), and epoxy resin (D) in the total solid content excluding the filler of the resin composition of the present disclosure is preferably 50% by mass or more, more preferably 65% by mass or more, and even more preferably 80% by mass or more. The total amount of the polyurethane resin (A), polyolefin resin (B), melamine resin (C), and epoxy resin (D) in the total solid content excluding the filler of the resin composition of the present disclosure may be 100% by mass.

[0168] [Other resins] The resin composition of the present disclosure may contain resins other than the polyurethane resin (A), polyolefin resin (B), melamine resin (C), and epoxy resin (D). The type and blending amount of the resin can be selected according to the use of the resin composition of the present disclosure. Examples of the resin include known thermoplastic resins.

[0169] [Conductive filler (E)] The resin composition of the present disclosure may contain a conductive filler (E). By containing the conductive filler, conductivity can be imparted to the resin composition and the cured product. The resin composition of the present disclosure may contain one type of the conductive filler (E) or two or more types thereof.

[0170] The volume resistivity of the conductive filler (E) is preferably less than 1.0×10 11 Ω·cm.

[0171] Examples of the conductive filler (E) include metal particles made of a conductive metal such as gold, platinum, silver, copper, nickel, or an alloy thereof; particles made of a conductive metal oxide such as indium tin oxide; carbon black; particles in which a core body (for example, resin particles, silica particles, metal particles, metal oxide particles, carbon black) is coated with a conductive metal, an alloy of a conductive metal, or a conductive polymer; and the like.

[0172] The shape of the conductive filler (E) is not limited, and it may be any of spherical, cubic, plate-like, columnar, needle-like, rod-like, flake-like, leaf-like, dendritic, grape-like, etc.

[0173] From the viewpoints of the conductivity of the resin composition and the cured product, and the storage stability of the resin composition, the average particle diameter of the conductive filler (E) is preferably 1 μm to 100 μm, more preferably 3 μm to 50 μm, and even more preferably 4 μm to 15 μm.

[0174] In the present disclosure, the average particle diameter of the filler is the median diameter (D50) of the particle size distribution based on volume. The particle size distribution based on volume is determined by measuring the diameter of the filler by the laser diffraction scattering method. As the laser diffraction scattering intensity distribution measuring device, LS13320 (Beckman Coulter, Inc.) and its Tornado dry powder sample module are preferable.

[0175] When the resin composition of the present disclosure contains the conductive filler (E), the content of the conductive filler (E) is, from the viewpoints of the conductivity of the resin composition and the cured product, the storage stability of the resin composition, and the adhesive strength of the resin composition and the cured product, preferably 1 part by mass to 500 parts by mass, more preferably 5 parts by mass to 400 parts by mass, even more preferably 10 parts by mass to 350 parts by mass, and even more preferably 20 parts by mass to 200 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin (A), the polyolefin resin (B), and the epoxy resin (D).

[0176] [Other fillers] The resin composition of the present disclosure may contain a filler having no conductivity. The resin composition of the present disclosure may contain one kind of filler having no conductivity or may contain two or more kinds thereof.

[0177] The filler having no conductivity may be an inorganic filler or an organic filler. Examples of the inorganic filler having no conductivity include calcium carbonate particles, titanium oxide particles, aluminum oxide particles, zinc oxide particles, talc particles, silica particles, and the like. Examples of the organic filler having no conductivity include (meth)acrylic resin particles, polybutadiene particles, nylon particles, polyolefin particles, polyester particles, polycarbonate particles, polyvinyl alcohol particles, polyvinyl ether particles, polyvinyl butyral particles, silicone rubber particles, polyurethane particles, phenol resin particles, polytetrafluoroethylene particles, and the like.

[0178] From the viewpoint of the storage stability of the resin composition, the average particle diameter (D50) of the inorganic filler having no conductivity is preferably from 0.001 μm to 50 μm, more preferably from 0.005 μm to 30 μm, and still more preferably from 0.01 μm to 10 μm.

[0179] From the viewpoint of the storage stability of the resin composition, the average particle diameter (D50) of the organic filler having no conductivity is preferably from 0.5 μm to 50 μm, more preferably from 1 μm to 30 μm.

[0180] [Hardening agent, hardening accelerator] The resin composition of the present disclosure may contain a hardening agent that reacts with the epoxy resin (D). Examples of the hardening agent include amine-based hardening agents, polyamideamine-based hardening agents, carboxylic acid-based hardening agents, basic active hydrogen-based hardening agents, polymercaptan-based hardening agents, novolak resin-based hardening agents, urea resin-based hardening agents, melamine resin-based hardening agents, and the like. One kind of hardening agent may be used, or two or more kinds may be used in combination.

[0181] The resin composition of the present disclosure may contain a curing accelerator that promotes the reaction of the epoxy resin (D). Examples of the curing accelerator include tertiary amine-based curing accelerators, tertiary amine salt-based curing accelerators, imidazole-based curing accelerators, and the like. One type of curing accelerator may be used, or two or more types may be used in combination.

[0182] When the resin composition of the present disclosure contains a curing accelerator, the content of the curing accelerator is preferably 1 to 30 parts by mass, more preferably 2 to 20 parts by mass, based on 100 parts by mass of the epoxy resin (D). From the viewpoint of the storage stability of the resin composition of the present disclosure, the lower the content of the curing accelerator, the more preferable.

[0183] [Flame retardant] The resin composition of the present disclosure may contain a flame retardant. Examples of the flame retardant include phosphorus-based flame retardants, nitrogen-based flame retardants, silicon-based flame retardants, metal hydroxides, metal oxides, metal carbonates, and the like. One type of flame retardant may be used, or two or more types may be used in combination.

[0184] [Organic solvent] As an example of an embodiment of the resin composition of the present disclosure, a liquid resin composition can be mentioned. An organic solvent can be mentioned as the solvent or dispersion medium of the liquid resin composition. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, n-butyl alcohol, benzyl alcohol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, and diacetone alcohol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexanone, and isophorone; aromatic hydrocarbons such as toluene, xylene, ethylbenzene, and mesitylene; esters such as methyl acetate, ethyl acetate, ethylene glycol monomethyl ether acetate, and 3-methoxybutyl acetate; aliphatic hydrocarbons such as hexane, heptane, cyclohexane, and methylcyclohexane; and the like. One type of organic solvent may be used, or two or more types may be mixed and used.

[0185] When the resin composition of the present disclosure is a liquid resin composition, the solid content concentration of the liquid resin composition is preferably 1% by mass to 90% by mass, more preferably 5% by mass to 70% by mass, and even more preferably 10% by mass to 50% by mass.

[0186] [Other components] The resin composition of the present disclosure may contain various additives. Examples of the additives include a coupling agent, a heat stabilizer, a leveling agent, an antifoaming agent, a tackifier, a colorant, and the like.

[0187] The resin composition of the present disclosure can be produced by mixing a polyurethane resin (A), a polyolefin resin (B), a melamine resin (C), an epoxy resin (D), and other components selected as needed.

[0188] An example of the use of the resin composition of the present disclosure is an adhesive composition. That is, the resin composition of the present disclosure contains at least one of a polyurethane resin (A) and a polyolefin resin (B), a melamine resin (C), and an epoxy resin (D), and the melamine resin (C) is preferably an adhesive composition that is 0.2 parts by mass to 10 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin (A) and the polyolefin resin (B). Hereinafter, the resin composition as an adhesive composition is also referred to as "the adhesive composition of the present disclosure".

[0189] The components, composition, and properties of the adhesive composition of the present disclosure are the same as those of the resin composition of the present disclosure in specific forms and preferred forms.

[0190] As an example of an embodiment of the adhesive composition of the present disclosure, a conductive adhesive composition containing a conductive filler (E) can be mentioned. The conductive adhesive composition is suitable for, for example, the production of a bonding sheet and an electromagnetic wave shielding material.

[0191] As an example of an embodiment of the adhesive composition of the present disclosure, a liquid adhesive composition can be mentioned. The solid content concentration of the liquid adhesive composition is preferably 5% by mass to 90% by mass, more preferably 10% by mass to 70% by mass, and even more preferably 15% by mass to 50% by mass.

[0192] Examples of the adherend of the adhesive composition of the present disclosure include objects made of polymer materials such as polyimide resin, polyamide resin, polyetheretherketone resin, polyphenylene sulfide resin, and liquid crystal polymer; objects made of metal materials such as copper, aluminum, and stainless steel; objects in which a polymer material and a metal material are combined; and the like. There is no limitation on the shape of the adherend.

[0193] According to the adhesive composition of the present disclosure, products having an adhesive layer (for example, a coverlay film, a bonding sheet) can be manufactured. In the present disclosure, a layer having adhesiveness formed using the adhesive composition of the present disclosure is referred to as an "adhesive layer".

[0194] According to the adhesive composition of the present disclosure, a cured layer in which the adhesive composition is cured can be formed on an adherend, and a composite in which the adherend and the cured layer are integrated can be manufactured. Further, according to the adhesive composition of the present disclosure, a plurality of adherends can be adhered to manufacture a composite in which the plurality of adherends are integrated.

[0195] <Laminate with an adhesive layer> Using the adhesive composition of the present disclosure, a laminate with an adhesive layer of the present disclosure is provided. The laminate with an adhesive layer of the present disclosure includes a base material and an adhesive layer disposed on the base material. The adhesive layer is an adhesive layer containing the adhesive composition of the present disclosure. The adhesive layer containing the adhesive composition is synonymous with the adhesive layer formed using the above-described adhesive composition of the present disclosure, and can also be referred to as an adhesive layer based on the adhesive composition of the present disclosure. The adhesive layer may be an uncured adhesive layer made of the adhesive composition, or a B-stage adhesive layer in which the adhesive composition is partially cured.

[0196] In the present disclosure, the "B-stage adhesive layer" means an adhesive layer in a semi-cured state in which a part of the adhesive composition has cured, and the adhesive layer is in a state where the curing of the adhesive composition can further proceed by treatment such as heating.

[0197] When the adhesive layer is formed on a substrate using a liquid adhesive composition, it is preferably a layer formed by removing at least a part of the solvent or dispersion medium from the liquid adhesive composition.

[0198] The thickness of the adhesive layer can be selected according to the use of the laminate with the adhesive layer. In an example of the embodiment, the thickness of the adhesive layer is preferably 1 μm to 100 μm, more preferably 3 μm to 80 μm, and even more preferably 5 μm to 50 μm.

[0199] The substrate may be a substrate that is retained on the adherend after the laminate with the adhesive layer is adhered to the adherend through the adhesive layer, or may be a substrate that is removed from the adherend (so-called release substrate).

[0200] The substrate is preferably a film-like substrate, and more preferably a resin film. The resin film may contain additives. Surface treatment may be applied to one or both surfaces of the resin film.

[0201] Examples of the resin film include polyimide film, polyamide film, liquid crystal polymer film, polyethylene terephthalate film, polyethylene naphthalate film, polyphenylene sulfide film, polyetherimide film, polyphenylene ether film, polyester film, polylactic acid film, nylon film, polyether ether ketone film, etc. As the resin film, from the viewpoints of heat resistance and insulation, polyimide film and polyamide film are preferable, and polyimide film is particularly preferable.

[0202] Examples of the resin film as the release substrate include polyethylene terephthalate film, polyethylene film, polypropylene film, silicone resin-coated paper, polyolefin resin-coated paper, polymethylpentene film, fluororesin film, and the like.

[0203] The thickness of the film-like substrate can be selected according to the use of the laminate with the adhesive layer. In an example of the embodiment, the thickness of the film-like substrate is preferably 3 μm to 125 μm.

[0204] The ratio T1 / T2 of the thickness T1 of the adhesive layer to the thickness T2 of the film-like substrate can be selected according to the use of the laminate with the adhesive layer. In an example of the embodiment, the ratio T1 / T2 is preferably 1 or more and 10 or less, and more preferably 1 or more and 5 or less.

[0205] The laminate with the adhesive layer of the present disclosure may be a laminate including a substrate (for example, a polyimide film) to be retained on the adherend on one surface of the adhesive layer and a release substrate on the other surface of the adhesive layer. That is, the laminate with the adhesive layer of the present disclosure may be a laminate having three layers of a substrate (for example, a polyimide film) / adhesive layer / release substrate.

[0206] The laminate with the adhesive layer of the present disclosure may be a laminate including release substrates on both surfaces of the adhesive layer. That is, the laminate with the adhesive layer of the present disclosure may be a laminate having three layers of a release substrate / adhesive layer / release substrate.

[0207] An example of the method for manufacturing the laminate with the adhesive layer of the present disclosure is given. A liquid adhesive composition is applied to one surface of the film-like substrate to form an adhesive composition layer. Then, the adhesive composition layer is dried to form a B-stage adhesive layer. The drying temperature is preferably 40°C to 250°C, and more preferably 70°C to 170°C. Drying can be carried out, for example, by hot air drying, far-infrared heating, or passing through a heating furnace.

[0208] <Coverlay film> The cover film of the present disclosure is provided by using the adhesive composition of the present disclosure. The cover film of the present disclosure includes an insulating film and an adhesive layer disposed on the insulating film. The adhesive layer is an adhesive layer containing the adhesive composition of the present disclosure. The adhesive layer containing the adhesive composition is synonymous with the adhesive layer formed by using the adhesive composition of the present disclosure described above, and can also be referred to as an adhesive layer based on the adhesive composition of the present disclosure. The adhesive layer may be an uncured adhesive layer made of the adhesive composition, or a B-stage adhesive layer in which the adhesive composition is partially cured. The cover film of the present disclosure is an example of an embodiment of the laminated body with the adhesive layer of the present disclosure.

[0209] In the cover film of the present disclosure, the thickness of the adhesive layer is preferably 1 μm to 80 μm, and more preferably 5 μm to 50 μm.

[0210] Examples of the insulating film include polyimide film, polyamide film, liquid crystal polymer film, polyethylene terephthalate film, polyethylene naphthalate film, polyphenylene sulfide film, polyetherimide film, polyphenylene ether film, polyester film, polylactic acid film, nylon film, polyether ether ketone film, etc. A polyimide film is preferred as the insulating film. The thickness of the insulating film is preferably 5 μm to 50 μm.

[0211] The cover film of the present disclosure may be a laminate having an insulating film on one surface of the adhesive layer and a release film on the other surface of the adhesive layer. That is, the cover film of the present disclosure may be a laminate having three layers of insulating film / adhesive layer / release film. Examples of the release film include polyethylene terephthalate film, polyethylene film, polypropylene film, silicone resin-coated paper, polyolefin resin-coated paper, polymethylpentene film, fluororesin film, etc.

[0212] An example of a method for manufacturing the cover film of the present disclosure will be given. A liquid adhesive composition is applied to one side of a polyimide film to form an adhesive composition layer. Next, the adhesive composition layer is dried to form a B-stage adhesive layer.

[0213] <Bonding sheet> Using the adhesive composition of the present disclosure, the bonding sheet of the present disclosure is provided. The bonding sheet of the present disclosure includes a release film and an adhesive layer disposed on the release film. The adhesive layer is an adhesive layer containing the adhesive composition of the present disclosure. The adhesive layer containing the adhesive composition is synonymous with the adhesive layer formed using the adhesive composition of the present disclosure described above, and can also be referred to as an adhesive layer based on the adhesive composition of the present disclosure. The adhesive layer may be an uncured adhesive layer composed of the adhesive composition, or a B-stage adhesive layer in which the adhesive composition is partially cured.

[0214] The bonding sheet of the present disclosure is an example of an embodiment of the laminated body with the adhesive layer of the present disclosure.

[0215] In the bonding sheet of the present disclosure, the thickness of the adhesive layer is preferably 5 μm to 100 μm, and more preferably 10 μm to 80 μm.

[0216] Examples of the release film include polyethylene terephthalate film, polyethylene film, polypropylene film, silicone resin-coated paper, polyolefin resin-coated paper, polymethylpentene film, fluororesin film, and the like. The thickness of the release film is preferably 20 μm to 100 μm.

[0217] The bonding sheet of the present disclosure may be a laminate provided with release films on both sides of the adhesive layer. That is, the bonding sheet of the present disclosure may be a laminate having three layers of release film / adhesive layer / release film. The two release films may be the same or different in terms of material and / or thickness.

[0218] An example of a method for manufacturing the bonding sheet of the present disclosure will be given. A liquid adhesive composition is applied to one side of a release film to form an adhesive composition layer. Next, the adhesive composition layer is dried to form a B-stage adhesive layer.

[0219] <Electromagnetic shielding material> Using the adhesive composition of the present disclosure, the electromagnetic shielding material of the present disclosure is provided. The electromagnetic shielding material of the present disclosure includes an adhesive layer or a cured layer containing the adhesive composition of the present disclosure. The adhesive layer or cured layer containing the adhesive composition is synonymous with the adhesive layer or cured layer formed using the adhesive composition of the present disclosure described above, and can also be referred to as an adhesive layer or cured layer based on the adhesive composition of the present disclosure. The adhesive layer may be an uncured adhesive layer made of the adhesive composition, or a B-stage adhesive layer in which the adhesive composition is partially cured. The cured layer is a layer in which the adhesive composition is cured.

[0220] In the electromagnetic shielding material of the present disclosure, the adhesive layer is a layer responsible for adhesion to the adherend. The electromagnetic shielding material of the present disclosure adheres to the adherend via the adhesive layer. After the electromagnetic shielding material of the present disclosure adheres to the adherend or during adhesion, the adhesive layer is cured by a treatment such as heating to become a cured layer. In the electromagnetic shielding material of the present disclosure, the cured layer can function as an electromagnetic shielding layer on the adherend. The electromagnetic shielding layer may have a single-layer structure composed only of the cured layer, or may have a laminated structure in which a metal foil layer is further laminated on the cured layer. It is preferable that the cured layer has conductivity. The cured layer may be isotropically conductive or anisotropically conductive. When the electromagnetic shielding layer has a single-layer structure, it is preferable that the cured layer is isotropically conductive, and when the electromagnetic shielding layer has a laminated structure, it is preferable that the cured layer is anisotropically conductive. The components and composition of the adhesive composition for forming the adhesive layer and the cured layer may be selected according to the properties (frequency, intensity, etc.) of the electromagnetic wave to be shielded and the shielding principle.

[0221] As an example of an embodiment of the electromagnetic shielding material of the present disclosure, a material used for coating a cable can be mentioned. Examples of the cable include cables inside electronic devices and communication cables.

[0222] As an example of an embodiment of the electromagnetic shielding material of the present disclosure, in an electronic device, a material for coating electronic device components used for the purpose of blocking external electromagnetic waves and / or blocking electromagnetic waves generated inside can be mentioned. As an example of the electromagnetic shielding material of this embodiment, a sheet-like electromagnetic shielding material, that is, an electromagnetic shielding sheet can be mentioned.

[0223] In the electromagnetic shielding sheet, the thickness of the adhesive layer is preferably 3 μm to 30 μm from the viewpoints of conductivity after curing and connectivity with the ground circuit.

[0224] The electromagnetic shielding sheet may further include a release film. Examples of the release film include polyethylene terephthalate film, polyethylene film, polypropylene film, silicone resin-coated paper, polyolefin resin-coated paper, polymethylpentene film, fluorine-based resin film, and the like.

[0225] The electromagnetic shielding sheet may further include a protective layer. The protective layer is preferably an insulating layer. The protective layer may be one layer or two layers.

[0226] The electromagnetic shielding sheet may be a laminate having three layers of a release film / adhesive layer / protective layer. The electromagnetic shielding sheet may be a laminate having four layers of a release film / adhesive layer / protective layer / reinforcing release film.

[0227] An example of a method for manufacturing the electromagnetic shielding sheet is given. A known composition for forming a protective layer is applied to one side of a reinforcing release film and dried to form a protective layer. Next, a liquid adhesive composition is applied onto the protective layer to form an adhesive composition layer, and a release film is placed on the adhesive composition layer. Then, the adhesive composition layer is dried to form a B-stage adhesive layer.

[0228] An example of a method of using the electromagnetic shielding sheet will be given by taking the laminate having the above-described three or four layers as an example. Peel off the release film of the electromagnetic shielding sheet to expose the adhesive layer. Place the electromagnetic shielding sheet on the printed wiring board such that the adhesive layer contacts the printed wiring board. Heat press from above the protective layer or the reinforcing release film to adhere the adhesive layer to the printed wiring board. The adhesive layer becomes soft by heating and flows into the ground portion of the printed wiring board by pressure. Further, post-cure is performed to cure the adhesive layer and form a cured layer.

[0229] <Composite> Using the adhesive composition of the present disclosure, the composite of the present disclosure is provided. The composite of the present disclosure includes an adherend and a cured layer in contact with the adherend. The cured layer is a cured layer containing the adhesive composition of the present disclosure, that is, a layer obtained by curing the adhesive composition of the present disclosure. The cured layer containing the adhesive composition is synonymous with the cured layer formed using the adhesive composition of the present disclosure described above, and can also be referred to as a cured layer based on the adhesive composition of the present disclosure.

[0230] The cured layer is a layer provided on the adherend to perform functions such as a protective layer, a conductive layer, an insulating layer, and an electromagnetic shielding layer on the adherend. The function of the cured layer is ensured by the components and composition of the adhesive composition of the present disclosure. The components and composition of the adhesive composition for forming the cured layer may be selected according to the function to be imparted to the cured layer.

[0231] The thickness of the cured layer can be selected according to the material or shape of the adherend and the use of the composite. In an example of the embodiment, the thickness of the cured layer is preferably 1 μm to 100 μm, more preferably 3 μm to 80 μm, and even more preferably 5 μm to 50 μm.

[0232] Examples of the adherend include an object made of a polymer material such as a polyimide resin, a polyamide resin, a polyetheretherketone resin, a polyphenylene sulfide resin, a liquid crystal polymer; an object made of a metal material such as copper, aluminum, stainless steel; an object in which a polymer material and a metal material are combined; and the like. There is no limitation on the shape of the adherend.

[0233] An example of the manufacturing method of the composite of the present disclosure will be given. A liquid adhesive composition is applied to one side of a film-like substrate to form an adhesive composition layer. Next, the adhesive composition layer is dried to form an adhesive layer. The adhesive layer and the adherend are brought into surface contact, heat lamination is performed, further heat pressing is performed, and further after-cure is performed to cure the adhesive layer. The heat lamination is performed, for example, at a temperature of 80°C to 150°C. The heat pressing is performed, for example, at a temperature of 150°C to 200°C and a pressure of 1 MPa to 3 MPa for 1 minute to 60 minutes. The after-cure is, for example, at a temperature of 100°C to 200°C for 30 minutes to 4 hours.

[0234] In the above manufacturing method, the film-like substrate may be a substrate that is retained on the adherend and becomes a part of the composite, or a substrate that is removed from the adherend (so-called release substrate). The specific form and preferred form of the film-like substrate are the same as those of the film-like substrate in the laminate with an adhesive layer.

[0235] As an example of an embodiment of the composite of the present disclosure, a flexible copper-clad laminate can be mentioned. The flexible copper-clad laminate includes, for example, a copper foil, a cured layer obtained by curing the adhesive composition of the present disclosure, and an insulating film (for example, a polyimide film, a polyamide film). Examples of the flexible copper-clad laminate include a five-layer laminate of copper foil / cured layer / insulating film / cured layer / copper foil, and a three-layer laminate of copper foil / cured layer / insulating film.

[0236] Examples of the copper foil of the flexible copper-clad laminate include an electrolytic copper foil, a rolled copper foil, and a copper foil plated with gold or silver. In the flexible copper-clad laminate, the thickness of the cured layer is preferably 5 μm to 50 μm. In the flexible copper-clad laminate, the thickness of the insulating film is preferably 5 μm to 50 μm.

Examples

[0237] Examples are given below to more specifically explain the resin composition of the present disclosure. Materials, amounts used, ratios, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present disclosure. Therefore, the scope of the resin composition of the present disclosure should not be construed as being limited by the specific examples shown below.

[0238] <Synthesis of polyurethane resin (A) and polyolefin resin (B)> [Synthesis Example 1: Polyphenylene ether polyurethane resin (a1)] Into a flask equipped with a stirrer, a reflux dehydration device, and a distillation tube, 100 parts by mass of polyphenylene ether (manufactured by SABIC, Noryl SA90), 8 parts by mass of 2-butyl-2-ethyl-1,3-propanediol, and 230 parts by mass of toluene were charged. After raising the temperature to 120 °C and distilling off 100 parts by mass of the solvent containing water, the temperature was lowered to 105 °C, and 0.8 part by mass of 2,2-bis(hydroxymethyl)propionic acid was charged and dissolved. Then, 22 parts by mass of 1,3-bis(isocyanatomethyl)cyclohexane was added, and after 30 minutes, 0.1 part by mass of dibutyltin dilaurate was added. After continuing the reaction for 12 hours, it was diluted with 30 parts by mass of toluene, 30 parts by mass of methyl ethyl ketone, and 15 parts by mass of 2-propanol to obtain a solution of polyphenylene ether polyurethane resin (a1). The weight average molecular weight of the polymer contained in the solution was 77,000, the number average molecular weight was 13,000, and the acid value was 2.6 mgKOH / g.

[0239] [Synthesis Example 2: Polyphenylene Ether Polyurethane Resin (a2)] Into a flask equipped with a stirrer, a reflux dehydration device, and a distillation tube, 70 parts by mass of polyphenylene ether (manufactured by SABIC, Noryl SA90), 30 parts by mass of polycarbonate diol (manufactured by UBE, ethanacol UH-100), 8 parts by mass of 2-butyl-2-ethyl-1,3-propanediol, and 230 parts by mass of toluene were charged. After raising the temperature to 120 °C and distilling off 100 parts by mass of the solvent containing water, the temperature was lowered to 105 °C, and 0.8 part by mass of 2,2-bis(hydroxymethyl)propionic acid was charged and dissolved. Then, 22 parts by mass of 1,3-bis(isocyanatomethyl)cyclohexane was added, and after 30 minutes, 0.1 part by mass of dibutyltin dilaurate was added. After continuing the reaction for 12 hours, it was diluted with 30 parts by mass of toluene, 30 parts by mass of methyl ethyl ketone, and 15 parts by mass of 2-propanol to obtain a solution of polyphenylene ether polyurethane resin (a2). The weight average molecular weight of the polymer contained in the solution was 88,000, the number average molecular weight was 11,000, and the acid value was 2.7 mgKOH / g.

[0240] [Synthesis Example 3: Polyphenylene Ether Polyurethane Resin (a3)] Into a flask equipped with a stirrer, a reflux dehydration device, and a distillation tube, 60 parts by mass of polyphenylene ether (manufactured by SABIC, Noryl SA90), 40 parts by mass of polycarbonate diol (manufactured by UBE, ethanacol UH-100), 8 parts by mass of 2-butyl-2-ethyl-1,3-propanediol, and 230 parts by mass of toluene were charged. After raising the temperature to 120 °C and distilling off 100 parts by mass of the solvent containing water, the temperature was lowered to 105 °C, and 0.8 part by mass of 2,2-bis(hydroxymethyl)propionic acid was charged and dissolved. Then, 22 parts by mass of 1,3-bis(isocyanatomethyl)cyclohexane was added, and after 30 minutes, 0.1 part by mass of dibutyltin dilaurate was added. After continuing the reaction for 12 hours, a solution of polyphenylene ether polyurethane resin (a3) diluted with 30 parts by mass of toluene, 30 parts by mass of methyl ethyl ketone, and 15 parts by mass of 2-propanol was obtained. The weight average molecular weight of the polymer contained in the solution was 78,000, the number average molecular weight was 17,000, and the acid value was 2.7 mgKOH / g.

[0241] [Synthesis Example 4: Polyolefin Resin (b1)] 100 parts by mass of a propylene-butene random copolymer consisting of 75 mol% of propylene units and 25 mol% of butene units, 22 parts by mass of maleic anhydride, and 6 parts by mass of di-t-butyl peroxide produced using a metallocene catalyst as a polymerization catalyst were dissolved in a toluene solvent. The obtained solution was heated to 140 °C in a 1 L autoclave and stirred at this temperature for an additional 3 hours. Then, the obtained reaction solution was cooled, and this reaction solution was poured into a container containing a large amount of methyl ethyl ketone to precipitate the resin. Thereafter, the remaining unreacted substances and the like were separated and purified by centrifugation. And the recovered resin was dried at 70 °C under reduced pressure for 5 hours to produce a modified polyolefin-based resin (b1). The produced modified polyolefin-based resin (b1) had a weight average molecular weight of 55,000 and an acid value of 30 mgKOH / g. Also, the content ratio of the graft portion constituting this modified polyolefin-based resin (b1) was 5.2 mass%.

[0242] [Synthesis Example 5: Polyolefin Resin (b2)] 100 parts by mass of hydrogenated styrene-butadiene block copolymer "Tuftec H1052" (trade name) manufactured by Asahi Kasei Corporation, 1.5 parts by mass of maleic anhydride, 0.8 parts by mass of lauryl methacrylate, and 1.2 parts by mass of di-t-butyl peroxide were kneaded and reacted using a twin-screw extruder with the maximum temperature in the cylinder part set at 170°C. Then, vacuum degassing was performed in the extruder to remove the remaining unreacted substances, and a modified polyolefin resin (b2) was produced. The produced modified polyolefin resin (b2) had a weight-average molecular weight of 60,000 and an acid value of 15 mgKOH / g. Also, the content ratio of the graft part constituting this modified polyolefin resin (b2) was 2.6% by mass.

[0243] [Method for Measuring Molecular Weight] The weight-average molecular weights of the resins produced in Synthesis Examples 1 to 5 were measured as follows. Gel permeation chromatography (GPC) measurement was performed using the following apparatus, column, column temperature, eluent, and detector to determine the weight-average molecular weight (Mw) of the resins produced in Synthesis Examples 1 to 5. Mw was converted based on the retention time measured by GPC with reference to the retention time of standard polystyrene. Apparatus: Alliance 2695 (manufactured by Waters) Column: 2 TSKgel SuperMultipore HZ-H, 2 TSKgel Super HZ2500, (manufactured by Tosoh Corporation) Column Temperature: 40°C Eluent: Tetrahydrofuran 0.35 ml / min Detector: Differential refractive index meter (RI) detector

[0244] [Method for Measuring Acid Value] 1 g of the resin produced in Synthesis Examples 1 to 5 was dissolved in 30 ml of toluene, and a device in which "APB-510-20B" manufactured by the same company was connected as a burette to the automatic titrator "AT-510" manufactured by Kyoto Electronics Industry Co., Ltd. was used. Potentiometric titration was performed using a 0.01 mol / L benzyl alcohol KOH solution as the titration reagent, and for the resins produced in Synthesis Examples 1 to 5, the number of mg of KOH per 1 g of resin was calculated as the acid value.

[0245] <Preparation of Resin Composition> [Examples 1 to 22 and Comparative Examples 1 to 6] The materials shown in Table 1 were placed in a flask equipped with a stirrer, and stirred at 60 °C for 6 hours to dissolve the resin and the curing accelerator in the solvent, and disperse the conductive filler and the flame retardant. Thus, a liquid resin composition was produced. Using these liquid resin compositions, a coverlay film, a bonding sheet, and adhesive test pieces A and B were produced as follows. The mass ratios of the respective materials other than the solvent in Table 1 represent the mass ratios of only the solid components of the materials shown below.

[0246] The materials used for the preparation of the resin composition are as follows. · Melamine resin (c1): Iminomethylol type melamine resin "Niclac MX-750" manufactured by Sanwa Chemical Co., Ltd., solid content ratio 75% by mass · Melamine resin (c2): Imino type melamine resin "Niclac MX-730" manufactured by Sanwa Chemical Co., Ltd., solid content ratio 80% by mass · Melamine resin (c3): Methylol type melamine resin "Niclac MW-12LF" manufactured by Sanwa Chemical Co., Ltd., solid content ratio 100% · Melamine resin (c4): Full ether type melamine resin "Niclac MW-30" manufactured by Sanwa Chemical Co., Ltd., solid content ratio 100% by mass · Epoxy resin (d1): Trisphenol methane type epoxy resin "jER 1032H60" manufactured by Mitsubishi Chemical Corporation · Epoxy resin (d2): Bisphenol A novolak type epoxy resin "EPICLON N-865" manufactured by DIC Corporation · Epoxy resin (d3): Dicyclopentadiene skeleton-containing epoxy resin "EPICLON HP-7200" manufactured by DIC Corporation · Conductive filler (E): Copper powder, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., FCC-115A · Flame retardant: Metal phosphinate, manufactured by Clariant, Exolit OP935 · Curing accelerator: Imidazole-based curing accelerator, manufactured by Shikoku Kasei Kogyo Co., Ltd., Curezol C11-Z · Solvent: A mixed solvent of toluene, methyl ethyl ketone and 2-propanol, with a mass ratio of toluene:methyl ethyl ketone:2-propanol = 100:15:5

[0247] <Preparation of Test Specimens> The resin compositions of Examples 1 to 22 and Comparative Examples 1 to 6 were used as adhesive compositions, and a coverlay film, a bonding sheet, Test Specimen A and Test Specimen B were prepared as follows.

[0248] (1) Coverlay Film A liquid adhesive composition was roll-coated on one side of a 25-μm-thick polyimide film so that the thickness after drying was 15 μm, and dried at a temperature of 120°C for 2 minutes to obtain a coverlay film having an adhesive layer.

[0249] (2) Test Specimen A A 35-μm-thick rolled copper foil (manufactured by Fukuda Metal Foil & Powder Co., Ltd.) was prepared. The copper foil and the above coverlay film were overlapped so that the mirror surface of the copper foil was in contact with the adhesive layer of the coverlay film, and laminated under the conditions of a temperature of 150°C, a pressure of 0.3 MPa, and a speed of 1 m / min. The obtained laminate (polyimide film / adhesive layer / copper foil) was heated and crimped at a temperature of 150°C and a pressure of 3 MPa for 5 minutes. Subsequently, post-cure was carried out in an oven at a temperature of 160°C for 2 hours to obtain Test Specimen A (polyimide film / adhesive layer / copper foil).

[0250] (3) Bonding Sheet A 35-μm-thick release PET film was prepared. A liquid adhesive composition was roll-coated on one side of the release PET film so that the thickness after drying was 25 μm, and dried at a temperature of 140°C for 2 minutes to obtain a bonding sheet having an adhesive layer containing copper powder.

[0251] (4) Test Specimen B A 300-μm-thick nickel-plated SUS304 plate was prepared. A flexible printed wiring board was prepared in which a copper circuit pattern was formed on one side of a polyimide film with a thickness of 25 μm, and a coverlay film with a thickness of 37.5 μm having through-holes with a diameter of 1 mm was laminated on the circuit pattern. The SUS304 plate and the above bonding sheet were overlapped so that the nickel-plated surface of the SUS304 plate contacted the adhesive layer of the bonding sheet, and lamination was performed under the conditions of a temperature of 150 °C, a pressure of 0.3 MPa, and a speed of 1 m / min to obtain a laminate (SUS plate / adhesive layer containing copper powder / release PET film). The release PET film was peeled off from the laminate, and the flexible printed wiring board was overlapped on the surface of the exposed adhesive layer, and heat-pressed at a temperature of 150 °C and a pressure of 3 MPa for 5 minutes. Then, post-cure was performed in an oven at a temperature of 160 °C for 2 hours to obtain test piece B (SUS plate / adhesive layer containing copper powder / flexible printed wiring board).

[0252] <Test> [Appearance after soldering test] In accordance with JIS C 6481 (1996) "Test Methods for Copper-Clad Laminates for Printed Wiring Boards", a soldering test was performed on test piece A. The soldering test was carried out under the test conditions of pre-treatment at 105 ± 2 °C and then floating the polyimide film side up in a solder bath at 280 °C for 60 seconds. For test piece A after the soldering test, the presence or absence of appearance abnormalities such as swelling and peeling of the adhesive layer was visually evaluated respectively. Those in which appearance abnormalities such as microvoids, swelling, and peeling were not confirmed were rated as "A", those in which slight microvoids were observed were rated as "B", and those in which appearance abnormalities such as swelling and peeling were confirmed were rated as "C".

[0253] [Peel adhesion strength (initial, after soldering test)] Before and after the solder test described in [Appearance after Solder Test], the peel adhesion strength was measured as follows. That is, in accordance with JIS C 6481 (1996) "Test Methods for Copper-Clad Laminates for Printed Wiring Boards", the 180° peel adhesion strength (N / cm) when peeling the copper foil of test piece A from the polyimide film was measured under the conditions of a temperature of 23°C and a tensile speed of 50 mm / min. The width of test piece A during measurement was 10 mm. And for test piece A before and after the solder test, those with a measured 180° peel adhesion strength of 4.5 N / cm or more were designated as "A", those with a strength of 3.0 N / cm or more and less than 4.5 N / cm were designated as "B", and those with a strength less than 3.0 N / cm were designated as "C".

[0254] [Connection Resistance Value (Initial, After Solder Test)] Before and after the solder test described in [Appearance after Solder Test], the connection resistance value was measured as follows. That is, the connection resistance value between the SUS plate and the copper foil circuit of the flexible printed wiring board in test piece B (SUS plate / adhesive layer containing copper powder / flexible printed wiring board) was measured with a resistance measuring instrument. And for test piece B before and after the solder test, the measured connection resistance values were classified as follows. A: Less than 0.1 Ω B: 0.1 Ω or more and less than 0.3 Ω C: 0.3 Ω or more and less than 1.0 Ω D: 1.0 Ω or more [Flammability] The coverlay film was heated and cured at 160°C for 2 hours, and the flammability was evaluated in accordance with UL-94. A: Pass (VTM-0 class) F: Fail

[0255] [Storage Stability] The adhesive composition was put into a glass bottle and sealed, and stored at a temperature of 5°C for a predetermined time. After storage, the presence or absence of gelation of the adhesive composition was visually confirmed. A: Gelation was not confirmed for more than one week. F: Gelation occurred in less than one week.

[0256] Table 1 shows the test results of the resin compositions (adhesive compositions) of Examples 1 to 22 and Comparative Examples 1 to 6.

[0257]

Table 1

[0258] As shown in Table 1, the resin compositions (adhesive compositions) of Examples 1 to 22 maintained excellent appearance even after the solder test and were excellent in the peel adhesion strength after the solder test as compared with the resin compositions (adhesive compositions) of Comparative Examples 1 to 6. Further, as shown in Table 1, the resin compositions (adhesive compositions) containing the conductive fillers of Examples 4 to 22 showed excellent connection resistance values after the solder test as compared with the resin compositions (adhesive compositions) of Comparative Examples 1 to 6.

Claims

1. Comprising at least one of a polyurethane resin (A) and a polyolefin resin (B), a melamine resin (C), and an epoxy resin (D), wherein the melamine resin (C) is 0.2 parts by mass to 10 parts by mass with respect to 100 parts by mass of the total amount of the polyurethane resin (A) and the polyolefin resin (B), a resin composition.

2. The resin composition according to claim 1, wherein the polyurethane resin (A) contains a polyurethane resin containing polyphenylene ether having at least two hydroxy groups in the molecule and polyisocyanate as polymerization components.

3. The resin composition according to claim 1, wherein the polyolefin resin (B) is a resin obtained by graft-modifying an unmodified polyolefin resin with a modifier containing an α,β-unsaturated carboxylic acid or a derivative thereof.

4. The resin composition according to claim 1, wherein the melamine resin (C) contains at least one alkylated melamine selected from the group consisting of imino-type alkylated melamine, methylol-type alkylated melamine, iminomethylol-type alkylated melamine, and fluether-type alkylated melamine as a structural unit.

5. The resin composition according to claim 1, wherein at least one of the polyurethane resin (A) and the polyolefin resin (B) has a weight average molecular weight of 30,000 or more.

6. The resin composition according to claim 1, containing 1 part by mass to 60 parts by mass of the epoxy resin (D) with respect to 100 parts by mass of the polyurethane resin (A) and the polyolefin resin (B).

7. The resin composition according to claim 1, further containing a conductive filler (E).

8. The resin composition according to claim 7, containing 10 parts by mass to 350 parts by mass of the conductive filler (E) with respect to 100 parts by mass of the total amount of the polyurethane resin (A), the polyolefin resin (B), and the epoxy resin (D).

9. The resin composition according to any one of claims 1 to 8, which is an adhesive composition.

10. A base material, An adhesive layer containing the resin composition according to claim 9 disposed on the base material, An adhesive layer-attached laminate comprising:

11. An insulating film, An adhesive layer containing the resin composition according to claim 9 disposed on the insulating film, A coverlay film comprising:

12. A release film, An adhesive layer containing the resin composition according to claim 9, disposed on the release film; A bonding sheet comprising the same. **Claim 13** An electromagnetic shielding material comprising an adhesive layer or a cured layer containing the resin composition according to claim 9. **Claim 14** An adherend; A cured layer containing the resin composition according to claim 9, disposed on the surface of the adherend; A composite comprising the same.

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