Curable Adhesive Sheet for Devices

Abstract

Curing properties for devices with adhesive layers that give cured products with excellent low dielectric properties in the high frequency range An adhesive sheet is provided. [Solution] The following component (A) 、 (B) Component , and component (D) For devices having an adhesive layer containing Curable adhesive sheet. Component (A): Polyphenylene ether resin having vinyl groups Component (B): A compound having two or more hydrocarbon groups with terminal double bonds. Component (D): Cationic polymerization initiator

Description

Technical Field

[0001] The present invention relates to a curable adhesive sheet for devices having an adhesive layer that provides a cured product excellent in low dielectric characteristics in the high-frequency region. In this specification, the high-frequency region refers to the region of 300 MHz to 3 00 GHz.

Background Art

[0002] In recent years, with the miniaturization and weight reduction of electronic devices, flexible printed wiring boards (FPCs) are increasingly being used as wiring members. An FPC can be obtained, for example, by subjecting a copper foil laminated on an insulating resin film such as polyimide (copper-clad laminate board) to an etching process to form an electric circuit. Also, usually, a coverlay film having an insulating resin base material and an adhesive layer is bonded to the copper foil on which an electric circuit is formed to protect the electric circuit.

[0003] By the way, in recent years, for communication devices such as smartphones, the high-frequencyization of electric signals has been progressing in order to handle larger amounts of data. However, since electric signals in the high-frequency region are likely to change into heat, transmission loss tends to increase when the electric signals are high-frequencyized.

[0004] In order to transmit electric signals in the high-frequency region at high speed and with suppressed transmission loss, the dielectric characteristics of insulators (base materials, adhesives, etc.) constituting the wiring member are improved (lower dielectric constant and lower dielectric tangent).

[0005] Patent Document 1 discloses a base material film and an adhesive layer on at least one surface of the base material film ​​​​​​A laminate with an adhesive layer, wherein the adhesive layer is made of a specific adhesive composition. A laminate with an adhesive layer is described. Patent Document 1 also describes that the laminate with the adhesive layer is excellent in electrical properties (low dielectric constant, low dielectric tangent), etc. It is also described.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The cured product of the adhesive composition described in Patent Document 1 has low dielectric properties (in this specification, "low dielectric properties" means "low dielectric constant and low dielectric tangent"). ). However, in order to cope with the further high-frequencyization of electrical signals expected in the future, it has been desired to form a cured product that is even more excellent in low dielectric properties in the high-frequency range.

[0008] The present invention has been made in view of the above circumstances, and an object thereof is to provide a curable adhesive sheet for a device having an adhesive layer that gives a cured product excellent in low dielectric properties in the high-frequency range.

Means for Solving the Problems

[0009] In order to solve the above problems, the present inventors have intensively studied a curable adhesive sheet for a device having an adhesive layer. As a result, by using a polyphenylene ether resin having a vinyl group and a compound having two or more hydrocarbon groups having a double bond at the terminal, low in the high-frequency range. It has been found that an adhesive layer capable of forming a cured product excellent in dielectric properties can be formed, and the present invention has been completed. Thus, according to the present invention, there is provided a curable adhesive sheet for devices of the following [1] to

[12] .

[0010] Thus, according to the present invention, there is provided a curable adhesive sheet for devices of the following [1] to

[12] . is provided.

[0011] 〔1〕A curable adhesive sheet for devices having an adhesive layer containing the following component (A) 、 component (B) and component (D) and having an adhesive layer containing the following component (A) is provided. (A) component: A polyphenylene ether resin having a vinyl group (B) component: A compound having two or more hydrocarbon groups having a double bond at the terminal (D) component: cationic polymerization initiator 〔2〕The curable adhesive sheet for devices according to [1], wherein the component (B) is a compound having a heterocyclic skeleton. is provided. 〔3〕The curable adhesive sheet for devices according to [2], wherein the heterocyclic skeleton is an isocyanurate skeleton or a glycoluril skeleton. is provided.

[0012] 〔4〕The curable adhesive sheet for devices according to any one of [1] to [3], wherein the molecular weight of the component (B) is 1,000 or less. is provided. 〔5〕The curable adhesive sheet for devices according to any one of [1] to [4], wherein the number of hydrocarbon groups having a double bond at the terminal of the component (B) is 2. is provided. 〔 6 〕The curable adhesive sheet for devices according to any one of [1] to 〕, wherein the adhesive layer contains an olefin resin as a binder resin. 5 is provided. 〔 7 〕The curable adhesive sheet for devices according to any one of [1] to 〕, wherein the adhesive layer contains a resin having a reactive functional group as a binder resin. 6 is provided.

[0013] 8 The adhesive layer is a layer containing a compound having a cyclic ether group, or a layer not containing a compound having a cyclic ether group, and the content of the compound having a cyclic ether group is less than 5% by mass in the adhesive layer. The curable adhesive sheet for a device according to any one of [1] to 7 described in []. 9 The adhesive layer is a layer containing a compound that is liquid at 25°C, and the content of the compound that is liquid at 25°C is 5% by mass or more in the adhesive layer. The curable adhesive sheet for a device according to any one of [1] to 8 described in []. 10 At least one of the compounds that are liquid at 25°C is a compound having two or more hydrocarbon groups having a double bond at the terminal. The curable adhesive sheet for a device according to 9 described in []. 11 Having two or more hydrocarbon groups having a double bond at the terminal and the content of the compound that is liquid at 25°C is 90% by mass or more of the total amount of the compounds that are liquid at 25°C. The curable adhesive sheet for a device according to 10 described in [].

Advantages of the Invention

[0014] According to the present invention, there is provided a curable adhesive sheet for a device having an adhesive layer that gives a cured product excellent in low dielectric characteristics in the high frequency region.

Embodiments for Carrying Out the Invention

[0015] The curable adhesive sheet for a device of the present invention has an adhesive layer containing the following component (A) and component (B). ​​​​​​​​​​(A) Component: Polyphenylene ether resin having a vinyl group (B) Component: Compound having two or more hydrocarbon groups having a double bond at the terminal

[0016] [(A) Component: Polyphenylene ether resin having a vinyl group] The adhesive layer of the curable adhesive sheet for a device of the present invention contains, as the (A) component, a polyphenylene ether resin having a vinyl group (hereinafter sometimes referred to as "polyphenylene ether resin (A)"). ). The polyphenylene ether resin refers to a resin having a polyphenylene skeleton in the main chain. The polyphenylene skeleton is represented by the following formula

[0017]

Chemical formula

[0018] represents a repeating unit, or a repeating unit in which a hydrogen atom in the above formula is substituted, and has a skeleton. .

[0019] Since the polyphenylene ether resin (A) has a polyphenylene ether skeleton, the cured product of the adhesive layer containing the polyphenylene ether resin (A) has excellent low dielectric characteristics.

[0020] Examples of the polyphenylene ether skeleton in the polyphenylene ether resin (A) include those represented by the following formula (1).

[0021]

Chemical formula

[0022] In formula (1), X is a divalent group represented by the following formula (2) or formula (3), and Y is the same Each is independently a divalent group represented by the following formula (4), and a and b are integers from 0 to 100 and at least one of a and b is 1 or more. * represents a bond (hereinafter the same applies).

[0023] [Chemical formula]

[0024] In formula (2), R 1 ~R 8 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 6 or fewer carbon atoms, or a phenyl group, preferably a hydrogen atom or a methyl group.

[0025] [Chemical formula]

[0026] In formula (3), R 9 ~R 16 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 6 or fewer carbon atoms, or a phenyl group, preferably a hydrogen atom or a methyl group. A represents a linear, branched, or cyclic divalent hydrocarbon group having 20 or fewer carbon atoms.

[0027] [Chemical formula]

[0028] In formula (4), R 17 ~R 20 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 6 or fewer carbon atoms, or a phenyl group, preferably a hydrogen atom or a methyl group.

[0029] As the polyphenylene ether skeleton in the polyphenylene ether resin (A), the following formula ​​​(5) can be mentioned.

[0030]

Chemical formula

[0031] Since the polyphenylene ether resin (A) has a vinyl group, the cured product of the adhesive layer containing the polyphenylene ether resin (A) is excellent in low dielectric characteristics, crosslinkability, and heat resistance. The vinyl group in the polyphenylene ether resin (A) may be a part of a hydrocarbon-based substituent such as a vinylbenzyl group or a vinylnaphthyl group. That is, the polyphenylene ether resin (A) is a polyphenylene ether skeleton to which a vinyl group or a vinyl group-containing hydrocarbon group is bonded. The vinyl group in the polyphenylene ether resin (A) may be a part of a hydrocarbon-based substituent such as a vinylbenzyl group or a vinylnaphthyl group. That is, the polyphenylene ether resin (A) is a polyphenylene ether skeleton to which a vinyl group or a vinyl group-containing hydrocarbon group is bonded. The vinyl group in the polyphenylene ether resin (A) may be a part of a hydrocarbon-based substituent such as a vinylbenzyl group or a vinylnaphthyl group. That is, the polyphenylene ether resin (A) is a polyphenylene ether skeleton to which a vinyl group or a vinyl group-containing hydrocarbon group is bonded. The vinyl group in the polyphenylene ether resin (A) may be a part of a hydrocarbon-based substituent such as a vinylbenzyl group or a vinylnaphthyl group. That is, the polyphenylene ether resin (A) is a polyphenylene ether skeleton to which a vinyl group or a vinyl group-containing hydrocarbon group is bonded. The vinyl group in the polyphenylene ether resin (A) may be a part of a hydrocarbon-based substituent such as a vinylbenzyl group or a vinylnaphthyl group. That is, the polyphenylene ether resin (A) is a polyphenylene ether skeleton to which a vinyl group or a vinyl group-containing hydrocarbon group is bonded.

[0032] As the polyphenylene ether resin (A), a cured product excellent in low dielectric characteristics is easily obtained. Therefore, those having vinyl groups or vinyl group-containing hydrocarbon groups at both ends of the polyphenylene ether skeleton are preferred. As the polyphenylene ether resin (A), a cured product excellent in low dielectric characteristics is easily obtained.

[0033] Such a polyphenylene ether resin (A) can be obtained by introducing vinyl groups or vinyl group-containing hydrocarbon groups at both ends after forming the polyphenylene ether skeleton. Such a polyphenylene ether resin (A) can be obtained by introducing vinyl groups or vinyl group-containing hydrocarbon groups at both ends after forming the polyphenylene ether skeleton. Such a polyphenylene ether resin (A) can be obtained by introducing vinyl groups or vinyl group-containing hydrocarbon groups at both ends after forming the polyphenylene ether skeleton. Specifically, after reacting a bifunctional phenol compound with a monofunctional phenol compound to obtain a polymer having phenolic hydroxyl groups at both ends, 4-(chloromethyl)styrene is used to vinylbenzyl etherify the terminal phenolic hydroxyl groups, thereby obtaining a polyphenylene ether resin (A) having vinylbenzyl groups at both ends of the polyphenylene ether skeleton. vinylbenzyl etherify the terminal phenolic hydroxyl groups, thereby obtaining a polyphenylene ether resin (A) having vinylbenzyl groups at both ends of the polyphenylene ether skeleton. vinylbenzyl etherify the terminal phenolic hydroxyl groups, thereby obtaining a polyphenylene ether resin (A) having vinylbenzyl groups at both ends of the polyphenylene ether skeleton. Such a polyphenylene ether resin (A) can be obtained.

[0034] Examples of the polyphenylene ether resin (A) include those represented by the following formula (6). .

[0035] [Chemical formula]

[0036] As the polyphenylene ether resin (A), commercially available products can also be used. Examples of commercially available products include modified polyphenylene ether resins such as OPE-2St manufactured by Mitsubishi Gas Chemical Company, Inc. (a modified polyphenylene ether resin having vinylbenzyl groups at both ends). For example, OPE-2St manufactured by Mitsubishi Gas Chemical Company, Inc. (a modified polyphenylene ether resin having vinylbenzyl groups at both ends), etc. can be mentioned. .

[0037] The weight average molecular weight (Mw) of the polyphenylene ether resin (A) is preferably 500 to 5,000, more preferably 500 to 3,000. . The weight average molecular weight (Mw) of the polyphenylene ether resin (A) can be determined as a standard polystyrene conversion value by performing gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent. .

[0038] The polyphenylene ether resin (A) can be used alone or in combination of two or more. .

[0039] The content of the polyphenylene ether resin (A) in the adhesive layer is preferably 10% by mass or more, more preferably 15 to 50% by mass. When the content of the binder resin described later is large, the content of the polyphenylene ether resin (A) in the adhesive layer may be 10 to 40% by mass. . When the content of the binder resin described later is large, the content of the polyphenylene ether resin (A) in the adhesive layer may be 10 to 40% by mass. . When the content of the polyphenylene ether resin (A) in the adhesive layer is 10% by mass or more, it becomes easier to obtain a cured product having excellent low dielectric characteristics while improving the curability of the adhesive layer. .​

[0040] 〔(B) component: A compound having two or more hydrocarbon groups having a double bond at the terminal〕 The adhesive layer of the curable adhesive sheet for a device of the present invention contains, as the (B) component, a compound having two or more hydrocarbon groups having a double bond at the terminal (hereinafter sometimes referred to as "polyfunctional compound (B)"). ).

[0041] Since the polyfunctional compound (B) has two or more hydrocarbon groups having a double bond at the terminal, the cured product of the adhesive layer containing the polyfunctional compound (B) is excellent in low dielectric characteristics, crosslinkability, and adhesive strength. The number of carbon atoms of the hydrocarbon group having a double bond at the terminal is preferably 2 to 10, more preferably 2 to 5. Examples of the hydrocarbon group having a double bond at the terminal include a vinyl group, an allyl group, a 3-butenyl group, a 4-pentenyl group, a 5-hexenyl group, an isopropenyl group, a 1-methyl-2-propenyl group, a vinylbenzyl group, a vinylnaphthyl group, and the like. Among these, an allyl group is preferred.

[0042] The number of hydrocarbon groups having a double bond at the terminal contained in the polyfunctional compound (B) is 2 or more. By having 2 or more hydrocarbon groups having a double bond at the terminal, a crosslinked structure is formed in the cured product, and a cured product having more excellent adhesive strength and heat resistance can be formed. In addition, from the viewpoint of suppressing the generation of cracks in the cured adhesive layer due to the crosslinked structure formed in the cured product being moderately sparse, the number of hydrocarbon groups having a double bond at the terminal is preferably 2 to 4, more preferably 2. When the number of hydrocarbon groups having a double bond at the terminal is 2, while exhibiting the curability of the polyfunctional compound (B), the blending of the polyfunctional compound (B) is such that Even when the amount is large, it is possible to suppress the curing shrinkage of the adhesive layer, and when the curable adhesive sheet is used for bonding a plate-like member such as a circuit board, it is possible to reduce the warpage of the plate-like member. When the double bonds of hydrocarbon groups having double bonds at their ends are polymerized, the distance between monomers before polymerization (i.e., the distance between double bonds indicated by the Van der Waals distance) becomes shorter due to polymerization to the distance between repeating units (the distance of covalent bonds in the polymer). Therefore, the larger the number of hydrocarbon groups having double bonds at their ends, the greater the tendency for the curing shrinkage of the curable adhesive layer to increase. By selecting a compound in which the number of hydrocarbon groups having double bonds at their ends is 2 as the polyfunctional compound (B), it is possible to efficiently suppress the curing shrinkage. When used for bonding a plate-like member such as a circuit board, the warpage of the plate-like member can be reduced. When the double bonds of hydrocarbon groups having double bonds at their ends are polymerized, the distance between monomers before polymerization (i.e., the distance between double bonds indicated by the Van der Waals distance) becomes shorter due to polymerization to the distance between repeating units (the distance of covalent bonds in the polymer). Therefore, the larger the number of hydrocarbon groups having double bonds at their ends, the greater the tendency for the curing shrinkage of the curable adhesive layer to increase. By selecting a compound in which the number of hydrocarbon groups having double bonds at their ends is 2 as the polyfunctional compound (B), it is possible to efficiently suppress the curing shrinkage. The polyfunctional compound (B) preferably has a heterocyclic skeleton. Since the polyfunctional compound (B) has a heterocyclic skeleton, it is easy to obtain a cured product having excellent adhesive strength and low dielectric properties. As the heterocyclic skeleton, an isocyanurate skeleton or a glycoluril skeleton can be mentioned.

[0043] As the polyfunctional compound (B) having an isocyanurate skeleton, compounds represented by the following formula (7) or (8) can be mentioned. As the heterocyclic skeleton, an isocyanurate skeleton or a glycoluril skeleton can be mentioned.

[0044] As the polyfunctional compound (B) having an isocyanurate skeleton, compounds represented by the following formula (7) or (8 ) can be mentioned.

[0045]

Chemical formula

[0046]

Chemical formula

[0047] In formula (7), R 21 , R 22represents, independently of each other, a hydrocarbon group having a double bond at the terminal and R 23 represents a saturated hydrocarbon group having 1 to 15 carbon atoms or an alkoxy group-substituted alkyl group having 1 to 15 carbon atoms . In formula (8), R 24 to R 26 each independently represents a hydrocarbon group having a double bond at the terminal .

[0048] R 21 , R 22 , R 24 , R 25 , R 26 The hydrocarbon group having a double bond at the terminal represented by is as described above.

[0049] R 23 The saturated hydrocarbon group represented by has 1 to 15 carbon atoms, preferably 5 to 15 carbon atoms , more preferably 8 to 15 carbon atoms. Examples of the saturated hydrocarbon group represented by R 23 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, s-butyl group, i sobutyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n- nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n- tetradecyl group, n-pentadecyl group, etc.

[0050] R 23 The alkoxy group-substituted alkyl group represented by has 2 to 15 carbon atoms, preferably 2 to 12 carbon atoms, more preferably 3 to 10 carbon atoms. Examples of the alkoxy group-substituted alkyl group represented by R 23 include methoxymethyl group, ethoxymethyl group, 2-methoxyethoxymethyl group, benzy loxymethyl group, etc. .

[0051] Examples of the polyfunctional compound (B) having a glycoluril skeleton include compounds represented by the following formula (9). .

[0052] [Chemical formula]

[0053] In formula (9), R 27 ~R 30 each independently represents a hydrocarbon group having 1 to 15 carbon atoms, and at least two of these are hydrocarbon groups having a double bond at the terminal. R , R 31 , R 3 2 represents a hydrogen atom or a saturated hydrocarbon group having 1 to 15 carbon atoms.

[0054] Among these, since a cured product with an appropriate crosslink density is easily obtained, as the polyfunctional compound (B ), a compound having an isocyanurate skeleton is preferable, a compound represented by formula (7) is more preferable, and from the viewpoint of further improving the low dielectric characteristics of the cured product of the adhesive layer and adjusting the molecular weight of the compound to an appropriate range, a compound represented by the following formula is even more preferable. [Chemical formula] In the formula, R represents a saturated hydrocarbon group having 5 to 15 carbon atoms, preferably a saturated hydrocarbon group having 8 to 15 carbon atoms.

[0055] [Chemical formula]

[0056] group is preferred.

[0057] As the polyfunctional compound (B), commercially available products can be used. For example, as the compound represented by formula (7), L-DAIC (manufactured by Shikoku Kasei Kogyo Co., Ltd.) can be mentioned. As the compound represented by formula (8), TAIC (manufactured by Mitsubishi Chemical Corporation) can be mentioned. The compound represented by the formula (9) includes TA-G (manufactured by Shikoku Kasei Kogyo Co., Ltd.).

[0058] The molecular weight of the polyfunctional compound (B) is preferably 1,000 or less, more preferably 800 or less, and even more preferably 500 or less. The polyfunctional compound (B) with a molecular weight of 1,000 or less tends to satisfy the requirement of being a liquid at 25°C. As described later, when the polyfunctional compound (B) is a compound that is liquid at 25°C, the adhesiveness of the adhesive layer at room temperature is improved. "Liquid at 25°C" means having fluidity at 25°C. For example, a compound that is liquid at 25°C is a compound having a viscosity measured at 25°C and 1.0 rpm using an E-type viscometer of , 2 to 10,000 mPa·s.

[0059] Also, the molecular weight of the polyfunctional compound (B) is preferably 100 or more, more preferably 200 or more, and even more preferably 275 or more. The polyfunctional compound (B) with a high molecular weight is difficult to volatilize even in the drying process when forming the adhesive layer or in the process of curing the adhesive layer even if it is a thermosetting process, so it is easier to obtain a cured product having the desired physical properties. The boiling point of the polyfunctional compound (B) is preferably 175 to 350°C, more preferably 200 to 300°C. Also, the 5% weight loss temperature of the polyfunctional compound (B) is preferably 175 to 350°C, more preferably 200 to 300°C.

[0060] The polyfunctional compound (B) can be used alone or in combination of two or more. The content of the polyfunctional compound (B) in the adhesive layer is preferably 5% by mass or more, more preferably is 6 to 50% by mass, more preferably 10 to 30% by mass. Polyfunctional compound (B) When the content of the binder resin described later is large, the content in the adhesive layer may be 6 to 30% % by mass. When the content of the polyfunctional compound (B) is 5% by mass or more in the adhesive layer, a cured product excellent in adhesive strength and low dielectric properties is easily obtained. Further, as described later, from the viewpoint of the adhesiveness of the adhesive layer at room temperature, it is preferable that the adhesive layer contains a compound that is liquid at 25°C. However, this compound that is liquid at 25°C is preferably a polyfunctional compound (B). That is, in terms of improving the adhesiveness of the adhesive layer at room temperature and promoting the curing reaction, a compound having a cyclic ether group and being liquid at 25°C is also considered effective. However, when using a compound having a cyclic ether group , there is a possibility that it becomes difficult to obtain a cured product excellent in low dielectric properties. In this regard, the polyfunctional compound (B) has a hydrocarbon group having a double bond, unlike the case of using a compound having a cyclic ether group, and thus the low dielectric property of the cured product tends to be maintained even if the content in the adhesive layer is large. Therefore, if the polyfunctional compound (B) is liquid at 25°C , it is possible to contain a compound that is liquid at 25°C in the adhesive layer in a suitable amount without impairing the low dielectric properties of the cured product. Therefore, the content of the polyfunctional compound (B) that is liquid at 25°C is preferably 5% by mass or more, more preferably 6 to 50% by mass , and even more preferably 10 to 30% by mass in the adhesive layer. When the content of the binder resin described later is large, the content of the polyfunctional compound (B) that is liquid at 25°C in the adhesive layer may be 6 to 30% by mass.

[0061] ​​ [(C) Component: Binder Resin] The adhesive layer of the curable adhesive sheet for a device of the present invention may contain a binder resin as the (C) component. As will be described later, the adhesive layer of the curable adhesive sheet for a device of the present invention may contain a compound that is liquid at 25°C. In such a case, the inclusion of a binder resin in the adhesive layer makes it easier to maintain the shape of the adhesive layer. As described later, the adhesive layer of the curable adhesive sheet for a device of the present invention may contain a compound that is liquid at 25°C. In such a case, the inclusion of a binder resin in the adhesive layer makes it easier to maintain the shape of the adhesive layer. The binder resin is not particularly limited as long as it is a polymer component that imparts film-forming properties and flexibility to the adhesive layer. Examples of the binder resin include olefin resins, acrylic polymers, polyester resins, polyvinyl alcohol resins, polyvinyl butyral, polyvinyl chloride, phenoxy resins, polyamide resins, cellulose-based materials, polyvinyl ethers, polyimide resins, styrene-isoprene-styrene block copolymers, styrene-butadiene-styrene block copolymers, and the like.

[0062] The binder resin is not particularly limited as long as it is a polymer component that imparts film-forming properties and flexibility to the adhesive layer. As the binder resin, an olefin resin is preferable because a cured product having excellent low dielectric characteristics can be easily obtained. An olefin resin refers to a polymer containing repeating units derived from an olefin monomer. The olefin resin may be a polymer consisting only of repeating units derived from an olefin monomer, or may be a polymer consisting of repeating units derived from an olefin monomer and repeating units derived from a monomer copolymerizable with the olefin monomer. However, from the viewpoint of easily obtaining a cured product having excellent low dielectric characteristics, it is preferable that the olefin resin is a polymer consisting only of repeating units derived from an olefin monomer. Examples of the binder resin include olefin resins, acrylic polymers, polyester resins, polyvinyl alcohol resins, polyvinyl butyral, polyvinyl chloride, phenoxy resins, polyamide resins, cellulose-based materials, polyvinyl ethers, polyimide resins, styrene-isoprene-styrene block copolymers, styrene-butadiene-styrene block copolymers, and the like. As the binder resin, an olefin resin is preferable because a cured product having excellent low dielectric characteristics can be easily obtained. Examples of the binder resin include olefin resins, acrylic polymers, polyester resins, polyvinyl alcohol resins, polyvinyl butyral, polyvinyl chloride, phenoxy resins, polyamide resins, cellulose-based materials, polyvinyl ethers, polyimide resins, styrene-isoprene-styrene block copolymers, styrene-butadiene-styrene block copolymers, and the like.

[0063] As the binder resin, an olefin resin is preferable because a cured product having excellent low dielectric characteristics can be easily obtained. As the binder resin, an olefin resin is preferable because a cured product having excellent low dielectric characteristics can be easily obtained. An olefin resin refers to a polymer containing repeating units derived from an olefin monomer. The olefin resin may be a polymer consisting only of repeating units derived from an olefin monomer, or may be a polymer consisting of repeating units derived from an olefin monomer and repeating units derived from a monomer copolymerizable with the olefin monomer. However, from the viewpoint of easily obtaining a cured product having excellent low dielectric characteristics, it is preferable that the olefin resin is a polymer consisting only of repeating units derived from an olefin monomer. An olefin resin refers to a polymer containing repeating units derived from an olefin monomer. The olefin resin may be a polymer consisting only of repeating units derived from an olefin monomer, or may be a polymer consisting of repeating units derived from an olefin monomer and repeating units derived from a monomer copolymerizable with the olefin monomer. However, from the viewpoint of easily obtaining a cured product having excellent low dielectric characteristics, it is preferable that the olefin resin is a polymer consisting only of repeating units derived from an olefin monomer. As the binder resin, an olefin resin is preferable because a cured product having excellent low dielectric characteristics can be easily obtained. As the binder resin, an olefin resin is preferable because a cured product having excellent low dielectric characteristics can be easily obtained.

[0064] As the olefin monomer, α-olefins having 2 to 8 carbon atoms are preferred, and ethylene, propylene, 1-butene, isobutylene, or 1-hexene are more preferred, and ethylene or propylene is even more preferred. These olefin monomers can be used alone or in combination of two or more. Examples of monomers copolymerizable with the olefin monomer include vinyl acetate, (meth)acrylic acid ester, styrene, etc. Here, "(meth)acrylic acid" means acrylic acid or methacrylic acid (the same applies hereinafter). These monomers copolymerizable with the olefin monomer can be used alone or in combination of two or more.

[0065] Examples of the olefin resin include ultra-low density polyethylene (VLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene, polypropylene (PP), ethylene-propylene copolymer, olefin elastomer (TPO), ethylene-vinyl acetate copolymer (EVA), ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, etc.

[0066] As the binder resin, a resin having a reactive functional group is preferred. By using a resin having a reactive functional group as the binder resin, a crosslinked structure involving the binder resin can be constructed in the cured product of the adhesive layer, and a cured product having excellent heat resistance can be formed. In addition, by using a resin having a reactive functional group as the binder resin, it is possible to bond to a difficult-to-bond substrate or the like. It is possible to form a cured product having sufficient adhesive strength even against such materials.

[0067] The reactive functional group includes a carboxyl group, a carboxylic anhydride group, and a carboxylic ester group. , hydroxyl group, epoxy group, amide group, ammonium group, nitrile group, amino group, imide group, Isocyanate group, acetyl group, thiol group, ether group, thioether group, sulfone group , phosphonic group, nitro group, urethane group, alkoxysilyl group, silanol group, halogen atom Children etc.

[0068] The resin having a reactive functional group may be a modified polyolefin resin described below or a valerate resin described above. Among the binder resins, phenoxy resins and cellulose-based materials can be mentioned. Among the binder resins, modified resins other than olefin-based resins can be mentioned.

[0069] The reason is that it is easy to obtain a cured product having excellent low dielectric properties and that it is easy to obtain a cured product having excellent heat resistance. Modified polyolefin resin is used as the binder resin because it is easy to obtain the desired product. preferable. Modified polyolefin resin is a precursor of olefin resin, which is modified by adding a modifier (within the molecule, A compound having a reactive functional group is used to modify the polymer. It is an olefin-based resin.

[0070] Modified polyolefin resins are used because they form cured products with superior adhesive strength. Preferably, the resin is an acid-modified polyolefin resin. Acid-modified polyolefin resin is a type of resin that is graft-modified with an acid or an acid anhydride. For example, olefin resins are mixed with unsaturated carboxylic acids or unsaturated carboxylic acid-free resins. React with a hydrate (hereinafter sometimes referred to as "unsaturated carboxylic acid, etc.") to introduce a carboxyl group or a carboxylic anhydride group (graft modification).

[0071] Examples of unsaturated carboxylic acids, etc. to be reacted with the olefin resin include maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid, tetrahydrophthalic acid, aconitic acid, etc. of uns saturated carboxylic acids; maleic anhydride, itaconic anhydride, glutaconic anhydride, citracon ic anhydride, aconitic anhydride, norbornenedicarboxylic anhydride, tetrahydrophthalic anhydride etc. of unsaturated carboxylic acid anhydrides; may be mentioned. These can be used alone or in combination of two or more. Among these, maleic anhydride is preferred because a cured product with more excellent adhesive strength can be easily obtained.

[0072] The amount of unsaturated carboxylic acid, etc. to be reacted with the olefin resin is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 3 parts by mass, and still more preferably 0.2 to 1 part by mass with respect to 100 parts by mass of the olefin resin. By curing the adhesive composition containing the acid-modified polyolefin resin thus obtained, a cured product with more excellent adhesive strength can be formed.

[0073] The method of introducing an unsaturated carboxylic acid unit or an unsaturated carboxylic acid anhydride unit into the olefin resin is not particularly limited. For example, in the presence of a radical generator such as organic peroxides or azonitriles, the olefin resin and unsaturated carboxylic acid, etc. are heated and melted above the melting point of the olefin resin and reacted, or the olefin resin and unsaturated carboxylic acid, etc. After dissolving the following in an organic solvent, heat and stir in the presence of a radical generator to cause a reaction Examples of methods for graft copolymerizing an unsaturated carboxylic acid or the like onto an olefin resin include those using .

[0074] As the acid-modified polyolefin resin, commercially available products can also be used. Commercially available products include for example, Admer (registered trademark) (manufactured by Mitsui Chemicals), Unistol (registered trademark) (manufactured by Mitsui Chemicals ), BondyRam (manufactured by Polyram), orevac (registered trademark) (manufactured by ARK EMA), Modic (registered trademark) (manufactured by Mitsubishi Chemical), etc.

[0075] The number average molecular weight (Mn) of the binder resin is preferably 10,000 to 150,000, more preferably 30,000 to 100,000. The number average molecular weight (Mn) of the binder resin can be determined as a standard polystyrene conversion value by performing gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent .

[0076] The binder resin can be used alone or in combination of two or more. . When the adhesive layer contains a binder resin, the content of the binder resin in the adhesive layer is preferably 40 to 80% by mass, more preferably 45 to 80% by mass. When the content of the binder resin is 40 to 80% by mass in the adhesive layer, it is easy to obtain an adhesive layer having both shape retention and tackiness.

[0077] [[(D) component: cationic polymerization initiator]] The adhesive layer of the curable adhesive sheet for a device of the present invention contains, as the (D) component, cationic polymerization It may contain an initiator. The cationic polymerization initiator can efficiently promote the polymerization reaction of component (A) and component (B), and moreover, it is preferable because it can improve the storage stability of the adhesive layer compared to other curing agents. Examples of the cationic polymerization initiator include thermal cationic polymerization initiators and photo cationic polymerization initiators, and thermal cationic polymerization initiators that enable polymerization through a simple process are preferable.

[0078] A thermal cationic polymerization initiator is a compound that can generate a cationic species that initiates polymerization upon heating. Examples of the thermal cationic polymerization initiator include sulfonium salts, quaternary ammonium salts, phosphonium salts, diazonium salts, iodonium salts, etc.

[0079] Examples of the sulfonium salt include triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium hexafluoroaluminate, tris(4-methoxyphenyl)sulfonium hexafluoroaluminate, diphenyl(4-phenylthiophenyl)sulfonium hexafluoroaluminate, etc.

[0080] Commercially available products can also be used as the sulfonium salt. Commercially available products include Adeka Opton SP-150, Adeka Opton SP-170, Adeka Opton CP-66, Adeka Opton CP-77 (above, manufactured by Adeka Corporation), Sun-Aid SI-60L, Sun-Aid SI-80L, Sun-Aid SI-100L, Sun-Aid SI-B2A, Sun-Aid SI-B3 (above, manufactured by Sanshin Chemical Co., Ltd.), CYRACURE UVI-6974, CYRACURE UVI- 6990 (all manufactured by Union Carbide), UVI-508, UVI-509 (all manufactured by Union Carbide) , General Electric), FC-508, FC-509 (all manufactured by Minnesota Massachusetts Inning & Manufacturing Co., Ltd.), CD-1010, CD-1011 (All of the above are manufactured by Thirstomer Corporation), and the CI series of products (manufactured by Nippon Soda Co., Ltd.).

[0081] Examples of quaternary ammonium salts include tetrabutylammonium tetrafluoroborate, Tetrabutylammonium hexafluorophosphate, Tetrabutylammonium hy tetraethylammonium tetrafluoroborate, tetraethylammonium sulfate, ethyl ammonium p-toluenesulfonate, N,N-dimethyl-N-benzylanilini N,N-Dimethyl-N-benzylanilinium tetrachloride Difluoroborate, N,N-dimethyl-N-benzylpyridinium hexafluoroanhydride Thiophenate, N,N-diethyl-N-benzyl trifluoromethanesulfonate, N,N -Dimethyl-N-(4-methoxybenzyl)pyridinium hexafluoroantimonate , N,N-diethyl-N-(4-methoxybenzyl)toluidinium hexafluoroan Timonate and the like.

[0082] The phosphonium salt is ethyltriphenylphosphonium hexafluoroantimonium. tetrabutylphosphonium hexafluoroantimonate, and tetrabutylphosphonium hexafluoroantimonate.

[0083] Diazonium salts include AMERICURE (manufactured by American Can Co.), ULTR ASET (manufactured by Adeka Corporation) and the like.

[0084] Examples of the iodonium salt include diphenyliodonium hexafluoroarsenate, bis (4-chlorophenyl)iodonium hexafluoroarsenate, bis(4-bromophenyl)iodonium hexafluoroarsenate, phenyl(4-methoxyphenyl)iodonium hexafluoroarsenate, and the like. Commercially available products such as UV- 9310C (manufactured by Toshiba Silicone Co., Ltd.), Photoinitiator 2074 (manufactured by Rhône- Poulenc Co., Ltd.), products of the UVE series (manufactured by General Electric Co., Ltd.), products of the FC series (manufactured by Minnesota Mining and Manufacturing Co., Ltd.) can also be used.

[0085] The cationic polymerization initiator can be used alone or in combination of two or more. When the adhesive layer contains a cationic polymerization initiator, the content of the cationic polymerization initiator is preferably 0.1 to 6 parts by mass, more preferably 0.3 to 5 parts by mass, and still more preferably 0.5 to 4 parts by mass with respect to 100 parts by mass of the total amount of the polyphenylene ether resin (A) and the polyfunctional compound (B).

[0086] The adhesive layer may contain a reactive curing agent other than the cationic polymerization initiator. Examples of the reactive curing agent other than the cationic polymerization initiator include amine compounds such as benzylmethylamine and 2,4,6-tris(dimethylaminomethyl)phenol; imidazole compounds such as 2-methylimidazole, 2-ethyl- 4-methylimidazole, and 2-heptadecylimidazole; Lewis acids such as boron trifluoride monoethylamine complex and boron trifluoride piperazine complex; peroxides such as di(t-butylperoxy)diisopropylbenzene; and other thermally reactive curing agents. ​ Examples of the agent include.

[0087] [(E) component: silane coupling agent] The adhesive layer of the curable adhesive sheet for the device of the present invention may contain a silane coupling agent as the (E) component. It may contain a ring agent. By the adhesive layer containing a silane coupling agent, a cured product with better adhesive strength can be easily obtained. It becomes easier to obtain.

[0088] As the silane coupling agent, a known silane coupling agent can be used. Among them, an organosilicon compound having at least one alkoxysilyl group in the molecule is preferred. Preferably. Examples of the silane coupling agent include 3-methacryloxypropylmethyldimethoxysilane , 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane , 3-methacryloxypropyltriethoxysilane, 3-acryloxy Silane coupling agents having a (meth)acryloyl group such as propyltrimethoxysilane ; Vinyltrimethoxysilane, vinyltriethoxysilane, dimethoxymethylvinylsilane , diethoxymethylvinylsilane, trichlorovinylsilane, vinyltris(2-methoxy Ethoxysilane) silane coupling agents having a vinyl group such as silane 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxy Propyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- Glycidoxypropyltriethoxysilane, 8-glycidoxyoctyltrimethoxysilane Silane coupling agents having an epoxy group such as silane Silane coupling agents having a styryl group such as p-styryltrimethoxysilane, p-styryltriethoxysilane, etc. Silane coupling agent to be used;

[0089] N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-a minoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3 -aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-a minopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl· butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride and other silane coupling agents having an amino group; 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane and the like silane coupling agents having a ureido group; 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane and the like having a halogen atom silane coupling agent; 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxy silane and other silane coupling agents having a mercapto group; bis(trimethoxysilylpropyl)tetrasulfide, bis(triethoxysilylpro pyl)tetrasulfide and other silane coupling agents having a sulfide group; 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltrieth oxysilane and other silane coupling agents having an isocyanate group; allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane and other a llyl group-containing silane coupling agent; Silane coupling agents having a hydroxyl group such as 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltriethoxysilane, etc. and the like; examples thereof include.

[0090] The silane coupling agent can be used alone or in combination of two or more. It is possible. When the adhesive layer contains a silane coupling agent, the content of the silane coupling agent is in the adhesive layer, preferably 0.01 to 5% by mass, more preferably 0.05 to 1% by mass. .

[0091] 〔Cyclic ether compound〕 The adhesive layer of the curable adhesive sheet for a device of the present invention may or may not contain a compound having a cyclic ether group. It may or may not contain.

[0092] Examples of the cyclic ether group include an oxirane group (epoxy group), an oxetane group (oxetanyl group), a tetrahydrofuryl group, a tetrahydropyranyl group, etc. and the like. In this specification, the oxirane group includes groups having an oxirane structure such as a glycidyl group, a glycidyl ether group, an epoxycyclohexyl group, etc.

[0093] The cured product of the adhesive layer containing a compound having a cyclic ether group tends to have excellent adhesive strength. There is. However, since a hydroxyl group is generated by the ring opening of the cyclic ether group, when the adhesive layer contains a compound having a cyclic ether group, it may be difficult to obtain a cured product excellent in low dielectric characteristics. There is a risk of becoming difficult.

[0094] Further, the adhesive layer of the curable adhesive sheet for a device of the present invention contains the above component (B). Therefore, even if the effect of the compound having a cyclic ether group is not utilized, the cured product is not sufficiently Has adhesive strength. Therefore, the adhesive layer of the curable adhesive sheet for devices of the present invention has a cyclic ether group. It is preferable that the composition contains almost no compounds that cause such reactions. The content of the compound having a cyclic ether group in the adhesive layer is preferably less than 5% by mass. and more preferably 3 mass % or less.

[0095] [Other ingredients] The adhesive layer of the curable adhesive sheet for devices of the present invention may be, within the scope of not impairing the effects of the present invention, Other ingredients may also be included. Other ingredients include UV absorbers, antistatic agents, light stabilizers, antioxidants, and resin stabilizers. Examples of additives include additives such as binders, fillers, pigments, extenders, and softeners. These may be used alone or in combination of two or more. When the adhesive layer contains these additives, the content of the additives is appropriately determined according to the purpose. It is possible. [Adhesive layer]

[0096] The adhesive layer of the curable adhesive sheet for devices of the present invention contains a compound that is liquid at 25°C. It is preferable to have As described above, the adhesive layer of the curable adhesive sheet for devices of the present invention is polyphenylene ether. Polyphenylene ether resin (A) has a relatively rigid molecular structure. Therefore, the adhesive layer containing the polyphenylene ether resin (A) can be easily bonded at room temperature (e.g., 2 5°C, same below) may be poorly applied. In this regard, by incorporating a compound that is liquid at 25°C into the adhesive layer, the adhesive layer can be attached at room temperature. Sexuality improves.

[0097] When the adhesive layer contains a compound that is liquid at 25°C, its content is, from the above viewpoints, in the adhesive layer, preferably 5% by mass or more, more preferably 6 to 50% by mass, even more preferably 10 to 30% by mass. When the content of the binder resin described later is large, the content of the compound that is liquid at 25°C may be 6 to 30% by mass in the adhesive layer.

[0098] At least one of the compounds that are liquid at 25°C is preferably a compound having two or more hydrocarbon groups having a double bond at the terminal (that is, a compound satisfying the requirements of component (B)). By using a compound that satisfies the requirements of component (B) as the compound that is liquid at 25°C, it is possible to achieve both high-level adhesion of the adhesive layer at room temperature and low dielectric properties of its cured product. From this viewpoint, the content of the compound having two or more hydrocarbon groups having a double bond at the terminal and being liquid at 25°C is preferably 90% by mass or more, more preferably 95% by mass or more, in the total amount of the compounds that are liquid at 25°C.

[0099] The method for forming the adhesive layer of the curable adhesive sheet for a device of the present invention is not particularly limited. For example, the adhesive layer can be formed using a casting method. When the adhesive layer is formed by the casting method, using a known method, the adhesive composition as a raw material is applied to the peeled layer surface of the base material or the release film, and the obtained coating film is dried to form the adhesive layer.

[0100] The adhesive composition contains the above components (A) and (B) and other optional components. ​​​​​​The adhesive composition may further contain a solvent. Examples of the solvent include aromatic hydrocarbon solvents such as benzene and toluene; ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as n-pentane, n-hexane, and n-heptane; alicyclic hydrocarbon solvents such as cyclopentane, cyclohexane, and methylcyclohexane; and the like. These solvents can be used alone or in combination of two or more. When the adhesive composition contains a solvent, the content of the solvent can be appropriately determined in consideration of coating properties and the like. The adhesive composition can be prepared by appropriately mixing and stirring each component according to a conventional method.

[0101] Examples of the method for applying the adhesive composition include spin coating method, spray coating method, bar coating method, knife coating method, roll coating method, blade coating method, die coating method, gravure coating method, and the like.

[0102] Examples of the method for drying the coating film include conventionally known drying methods such as hot air drying, hot roll drying, and infrared irradiation. Examples of the conditions for drying the coating film are, for example, 80 to 150 °C for 30 seconds to 5 minutes.

[0103] The thickness of the adhesive layer is not particularly limited, but is usually 1 to 50 μm, preferably 1 to 25 μm, more preferably 5 to 25 μm. The adhesive layer having a thickness within the above range is suitably used as a material for forming a circuit board. The thickness of the adhesive layer can be measured in accordance with JIS K 7130 (1999) using a known thickness gauge. It can be measured in accordance with JIS K 7130 (1999) using a known thickness gauge.

[0104] The adhesive layer of the curable adhesive sheet for a device of the present invention has curability. From the viewpoint of being polymerizable by a simple process and being suitable for the use of the curable adhesive sheet for a device of the present invention, in the case of circuit board applications where the thermosetting method is frequently used, the curability is preferably thermosetting. From the viewpoint of being polymerizable by a simple process and being suitable for the use of the curable adhesive sheet for a device of the present invention, in the case of circuit board applications where the thermosetting method is frequently used, the curability is preferably thermosetting. In this case, by heating the adhesive layer, the adhesive layer is cured. In this case, by heating the adhesive layer, the adhesive layer is cured. .

[0105] When the curable adhesive sheet for a device of the present invention is thermosetting, the conditions for thermosetting the adhesive layer are not particularly limited. When the curable adhesive sheet for a device of the present invention is thermosetting, the conditions for thermosetting the adhesive layer are not particularly limited. The heating temperature is 80 to 200 °C, preferably 90 to 190 °C, from the viewpoint of efficiently promoting the reaction of the polyphenylene ether resin having a vinyl group. The heating temperature is 80 to 200 °C, preferably 90 to 190 °C, from the viewpoint of efficiently promoting the reaction of the polyphenylene ether resin having a vinyl group. The heating time is usually 30 minutes to 12 hours, preferably 1 to 6 hours. Also, when the curable adhesive sheet for a device of the present invention is photocurable, for example, ultraviolet rays can be irradiated onto the adhesive layer as the light for photocuring the adhesive layer. Also, when the curable adhesive sheet for a device of the present invention is photocurable, for example, ultraviolet rays can be irradiated onto the adhesive layer as the light for photocuring the adhesive layer.

[0106] The cured product of the adhesive layer is excellent in low dielectric characteristics in the high-frequency region. The relative permittivity of the cured product of the adhesive layer at 23 °C and a frequency of 1 GHz (hereinafter, this relative permittivity may be referred to as "relative permittivity (α)".) is preferably 2.50 or less, more preferably 2.40 or less. There is no particular lower limit for the relative permittivity (α), but it is usually 2.00 or more.

[0107] The dielectric tangent of the cured product of the adhesive layer at 23 °C and a frequency of 1 GHz (hereinafter, this dielectric tangent is sometimes referred to as "dielectric tangent (β)". The dielectric tangent (β) is preferably 0.0030 or less. , and more preferably 0.0020 or less. There is no particular lower limit for the dielectric tangent (β), but it is usually 0.0001 or more.

[0108] The measurement samples for the dielectric constant (α) and dielectric loss tangent (β) were prepared with the adhesive layer fully cured. If any, there is no particular limitation. For example, if the adhesive layer being measured has recommended curing conditions, it should be cured under those recommended conditions. The cured adhesive layer is used as a sample for measuring the relative dielectric constant (α) and dielectric loss tangent (β). If the adhesive layer is heat curable and there are no recommended curing conditions or they are unknown, use e.g. The hardened product obtained by hardening at 0°C for 1 hour was subjected to measurement of the relative dielectric constant (α) and dielectric loss tangent (β). It may also be used as a fee. The relative dielectric constant (α) and the dielectric loss tangent (β) can be measured according to the method described in the Examples. Cut.

[0109] [Curable adhesive sheet for devices] The curable adhesive sheet for devices of the present invention may have a substrate in addition to the adhesive layer. stomach. As the substrate, a resin film can usually be used. The resin component of the resin film may be polyimide, polyamide, polyamideimide, poly Phenylene ether, polyether ketone, polyether ether ketone, polyolefin Polyester, Polycarbonate, Polysulfone, Polyethersulfone, Polyphen Nylene sulfide, polyarylate, acrylic resin, cycloolefin polymer, aromatic Examples of the material include aromatic polymers, polyurethane polymers, and liquid crystal polymer films. The thickness of the substrate is not particularly limited, but is preferably 10 to 500 μm, more preferably 10 is from 1 to 300 μm, more preferably from 15 to 200 μm.

[0110] The curable adhesive sheet for devices of the present invention may have a release film in addition to the adhesive layer. It may be. The release film functions as a protective film for the adhesive layer until the curable adhesive sheet for devices is used. Also, when the curable adhesive sheet for devices does not have a base material, the release film functions as a support in the manufacturing process of the curable adhesive sheet for devices. When using the curable adhesive sheet for devices of the present invention, usually, the release film is peeled off and removed. When using the curable adhesive sheet for devices of the present invention, usually, the release film is peeled off and removed. When using the curable adhesive sheet for devices of the present invention, usually, the release film is peeled off and removed. As the release film, conventionally known ones can be used. For example, those having a release layer peeled by a release agent on a base material for the release film can be mentioned. As the release film, conventionally known ones can be used. For example, those having a release layer peeled by a release agent on a base material for the release film can be mentioned.

[0111] As the release film, conventionally known ones can be used. For example, those having a release layer peeled by a release agent on a base material for the release film can be mentioned. As the release film, conventionally known ones can be used. For example, those having a release layer peeled by a release agent on a base material for the release film can be mentioned. As the base material for the release film, paper base materials such as glassine paper, coated paper, and high-quality paper; laminated papers obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials; plastic films such as polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, polypropylene resin, and polyethylene resin; etc. can be mentioned. As the base material for the release film, paper base materials such as glassine paper, coated paper, and high-quality paper; laminated papers obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials; plastic films such as polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, polypropylene resin, and polyethylene resin; etc. can be mentioned. As the release agent, silicone-based resins, olefin-based resins, isoprene-based resins, rubber-based elastomers such as butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, fluorine-based resins, etc. can be mentioned. As the release agent, silicone-based resins, olefin-based resins, isoprene-based resins, rubber-based elastomers such as butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, fluorine-based resins, etc. can be mentioned.

[0112] As the release agent, silicone-based resins, olefin-based resins, isoprene-based resins, rubber-based elastomers such as butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, fluorine-based resins, etc. can be mentioned. As the release agent, silicone-based resins, olefin-based resins, isoprene-based resins, rubber-based elastomers such as butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, fluorine-based resins, etc. can be mentioned. As the release agent, silicone-based resins, olefin-based resins, isoprene-based resins, rubber-based elastomers such as butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, fluorine-based resins, etc. can be mentioned. The thickness of the release film is not particularly limited, but is usually about 20 to 250 μm.

[0113] When the curable adhesive sheet for devices of the present invention has a release film, the adhesive There may be a total of two release films, one on each side of the layer, or there may be a release film on only one side of the adhesive layer. When the curable adhesive sheet for a device has two release films on the front and back of the adhesive layer, the release forces of the respective release films may be different. As described above, the cured product of the adhesive layer of the curable adhesive sheet for a device of the present invention is excellent in low dielectric characteristics in the high frequency region. Therefore, the curable adhesive sheet for a device of the present invention is suitably used when forming members in a device that requires low dielectric characteristics. For example, by using the curable adhesive sheet for a device of the present invention, a cured adhesive layer constituting a circuit board can be efficiently formed. That is, the curable adhesive sheet for a device of the present invention can be used as a curable adhesive sheet for a circuit board. Examples of the circuit board include flexible printed wiring boards and the like.

[0114]

[0115]

[0116]

Examples

[0115] Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

[0116] 〔Compounds used in Examples or Comparative Examples〕 · Polyphenylene ether resin (A1): Vinylbenzyl-modified polyphenylene ether [manufactured by Mitsubishi Gas Chemical Company, trade name: OPE-2St 1200, number average molecular weight: 1200] · Polyphenylene ether resin (A2): Vinylbenzyl-modified polyphenylene ether [manufactured by Mitsubishi Gas Chemical Company, trade name: OPE-2St 2200, number average molecular weight: 2200] · Polyfunctional compound (B1): Diallyl compound having an isocyanurate skeleton (manufactured by Shikoku Chemicals Corporation, trade name: L-DAIC) · Cyclic ether group-containing compound (BX1): Hydrogenated bisphenol A type epoxy resin [manufactured by Mitsubishi Chemical Corporation, trade name: YX8000, epoxy equivalent: 205 g / eq, liquid at 25 °C] · Binder resin (C1): Acid-modified α-olefin polymer [manufactured by Mitsui Chemicals, trade name: Unistole H-200, number average molecular weight: 47,000] · Cationic polymerization initiator (D1): Sulfonium salt-based thermal cationic polymerization initiator [manufactured by Sanshin Chemical Industry Co., Ltd., trade name: Sun-Aid SI-B3] · Silane coupling agent (E1): 8-Glycidoxy octyltrimethoxysilane [manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM4803] · [Example 1] 50 parts by mass of polyphenylene ether resin (A1), 10 parts by mass of polyfunctional compound (B1), 100 parts by mass of binder resin (C1), 0.5 parts by mass of cationic polymerization initiator (D1), and 0.2 parts by mass of silane coupling agent (E1) were dissolved in toluene to prepare an adhesive composition. This adhesive composition was coated on the release-treated surface of a release film (first release film, manufactured by Lintec Corporation, trade name: SP-PET752150), and the obtained coating film was dried at 100 °C for 2 minutes to form an adhesive layer with a thickness of 15 μm. Another release film (second release film, manufactured by Lintec Corporation, trade name: SP-PET381130) was laminated on this adhesive layer to obtain a curable adhesive sheet (thermosetting adhesive sheet). · [Examples 2 to 6, Comparative Examples 1 to 4]

[0117]

[0118] ​​​​​​​​​​​​Except that the types and amounts of the respective components constituting the adhesive composition were changed to those described in Table 1 An adhesive composition and a thermosetting adhesive sheet were obtained in the same manner as in Example 1.

[0119] The following tests were conducted on the thermosetting adhesive sheets obtained in Examples 2 to 6 and Comparative Examples 1 to 4 . The results are shown in Table 1.

[0120] [Relative permittivity, dielectric loss tangent] The adhesive layer of the thermosetting adhesive sheet obtained in the example or comparative example was made to have a thickness of about 1 mm A plurality of sheets were laminated to obtain a laminate having a structure of release film / adhesive layer with a thickness of about 1 mm / release film . This laminate was heated at 160 ° C for 1 hour to cure the adhesive layer having a thickness of about 1 mm . After that, the release films on both sides were peeled off to obtain a measurement sample. Regarding the obtained measurement sample, using an RF impedance / material analyzer (manufactured by Keysight Technologies, E4991A), the relative permittivity and dielectric loss tangent at 23 ° C and 1 GHz were measured . In the example or comparative example, 1 GHz was adopted as an example in the high frequency region.

[0121] [Table 1]

[0122] It can be seen from Table 1 that The cured product of the adhesive layer of the curable adhesive sheet obtained in Examples 1 to 6 has low dielectric properties in the high frequency region . On the other hand, since the adhesive layer of the curable adhesive sheet obtained in Comparative Examples 1 to 4 contains a compound having a cyclic ether group instead of the component (B) of the present invention, the cured products of these adhesive layers are inferior in low dielectric properties in the high frequency region .

Claims

1. A curable adhesive sheet for a device having an adhesive layer containing the following component (A), component (B1) as a compound (B) having two or more hydrocarbon groups having a double bond at the terminal, and component (C). Component (A): A polyphenylene ether resin having a vinyl group Component (B1): A compound having two hydrocarbon groups having a double bond at the terminal and having an isocyanurate skeleton Component (C): A binder resin containing a polymer having a reactive group introduced into the main chain consisting only of repeating units derived from one or more olefinic monomers

2. A curable adhesive sheet for a device having an adhesive layer containing the following component (A), component (B1) as a compound (B) having two or more hydrocarbon groups having a double bond at the terminal, and component (E). Component (A): A polyphenylene ether resin having a vinyl group Component (B1): A compound having two hydrocarbon groups having a double bond at the terminal and having an isocyanurate skeleton Component (E): A silane coupling agent

3. The curable adhesive sheet for a device according to claim 1 or 2, wherein the molecular weight of the component (B1) is 1,000 or less.

4. The curable adhesive sheet for a device according to any one of claims 1 to 3, wherein the content of the component (A) is 10% by mass or more in the adhesive layer.

5. The curable adhesive sheet for a device according to any one of claims 1 to 4, wherein the content of the component (A) is 10 to 40% by mass in the adhesive layer.

6. The curable adhesive sheet for a device according to claim 2, wherein the adhesive layer further contains the following component (C). Component (C): A binder resin

7. The curable adhesive sheet for a device according to claim 6, wherein the binder resin is a resin having a reactive functional group.

8. The curable adhesive sheet for a device according to any one of claims 1, 6 and 7, wherein the content of the component (C) is 40 to 80% by mass in the adhesive layer.

9. The curable adhesive sheet for a device according to claim 1, wherein the adhesive layer further contains the following component (E). Component (E): A silane coupling agent

10. The curable adhesive sheet for a device according to any one of claims 1 to 9, wherein the adhesive layer is a layer containing a compound having a cyclic ether group or a layer not containing a compound having a cyclic ether group, and the content of the compound having a cyclic ether group is less than 5% by mass in the adhesive layer.

11. The curable adhesive sheet for a device according to any one of claims 1 to 10, wherein the adhesive layer is a layer containing a compound that is liquid at 25°C, and the content of the compound that is liquid at 25°C is 5% by mass or more in the adhesive layer.

12. The curable adhesive sheet for a device according to claim 11, wherein at least one of the compounds that are liquid at 25°C is the component (B).

13. The curable adhesive sheet for a device according to claim 12, wherein the content of the component (B) in the compound that is liquid at 25°C is 90% by mass or more based on the total amount of the compound that is liquid at 25°C.

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