Polymer, curable resin composition, stretchable insulating cured film obtained by curing said composition, insulating cured film for touch panel, touch panel, insulating cured film for flexible printed circuit board, and flexible printed circuit board

Abstract

A polymer containing: a unit B1 derived from an alkyl (meth) acrylate monomer (B1) containing a C5-20 linear or branched aliphatic hydrocarbon group which may have an unsaturated bond and may be substituted by a halogen; a unit B2 derived from a (meth) acrylate monomer (B2) having an ether bond; and a unit B3 that is derived from a (meth) acrylate monomer (B3) represented by formula (1). (R2 represents a hydrogen atom or a group selected from the group consisting of groups represented by formula (2). ) (R3 is a group selected from the group consisting of formula (3) and formula (4). > # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a polymer, a curable resin composition containing the polymer, and an insulating cured film obtained by curing the composition, for example, a curable resin composition useful for applications of elongated insulating cured films used in touch panels, flexible printed circuit boards, etc. (e.g., insulating film applications, protective film applications, flat film applications, etc.), an insulating cured film for touch panels obtained by curing the composition, a touch panel having the cured film, an insulating cured film for flexible printed circuit boards, and a flexible printed circuit board having the cured film. Background Art

[0002] In recent years, with the progress of electronic devices becoming more advanced, diversified, small and lightweight, the following devices have increased. The devices have a transparent touch panel installed on the front of a display element such as a liquid crystal, and the text, symbols, patterns, etc. displayed on the display element are visually recognized and selected through the transparent touch panel, and the functions of the device are switched by operating the transparent touch panel.

[0003] In addition, with the development of communication technology and the diversification of electronic devices, the peripheral materials are required to have higher functionality and performance. For example, in recent years, devices with flexible mechanisms such as flexible displays, touch panels, and flexible printed circuit boards are being developed, and as one of the high-functionality requirements of peripheral materials, flexibility and elongation are required.

[0004] On the other hand, when the touch panel is combined with a liquid crystal display device, it can be divided into an external (Out-cell) structure, an external embedded (On-cell) structure, and an internal (In-cell) structure according to its setting location. In recent years, external embedded structures and internal embedded structures with excellent visibility have gradually become mainstream. In these external embedded structures and internal embedded structures, the touch panel is assembled in the liquid crystal panel. In such a liquid crystal display device, an insulating film is used. As a material for the insulating film, for example, many curable resin compositions using specific alkali-soluble resins are known (for example, see Patent Document 1).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. WO / 2020 / 251004 Summary of the invention

[0008] Problems to be solved by the invention

[0009] In order to form an insulating film used in a touch panel, a liquid crystal display device, etc., a curable resin composition is often used. On the other hand, in order to exert softness and flexibility in an insulating film used in a flexible device, elongation is sometimes required. However, although the curable resin composition described in Patent Document 1 can form a cured film with excellent chemical resistance and developability, it is not a cured film with sufficient elongation.

[0010] As described above, there is a high demand for insulating films and the like that can be used in flexible electronic devices, and development of a curable resin composition having excellent elongation is desired.

[0011] In order to solve the above-mentioned problems, the object of the present invention is to provide a novel polymer and a curable resin composition capable of forming a cured film with excellent elongation, an elongated insulating cured film and an insulating cured film for a touch panel obtained by curing the composition, a touch panel, an insulating cured film for a flexible printed circuit board, and a flexible printed circuit board.

[0012] Means for solving problems

[0013] <1>

[0014] A polymer comprising:

[0015] Unit B1 derived from an alkyl (meth)acrylate monomer (B1) containing a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen;

[0016] Unit B2 derived from a (meth)acrylate monomer (B2) having an ether bond; and

[0017] The unit B3 is derived from a (meth)acrylic acid ester monomer (B3) represented by the following formula (1).

[0018] [Chemical formula 1]

[0019]

[0020] (In formula (1), R 1 represents a hydrogen atom or a methyl group. 2 is a hydrogen atom or a group selected from the groups represented by the following formula (2).

[0021] [Chemical formula 2]

[0022]

[0023] (In formula (2), X 1 R represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.3 is a group selected from the following formula (3) or the following formula (4).

[0024] [Chemical formula 3]

[0025]

[0026] (In formula (3), X 2 It represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

[0027] [Chemical formula 4]

[0028]

[0029] In formula (4), ring A represents a cyclic hydrocarbon group having 3 to 10 carbon atoms which may have an unsaturated bond, in which a part of the carbon atoms constituting the ring may be replaced by oxygen or nitrogen and which may have a substituent, or an aromatic group having 4 to 10 carbon atoms which may have a substituent. 4 is a group selected from the group consisting of a linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms and a carboxyl group. n represents an integer greater than 1, and at least one R 4 is a carboxyl group.)

[0030] <2>

[0031] As mentioned above <1> The polymer, wherein the unit B1 is represented by the following formula (B1-1).

[0032] [Chemical formula 5]

[0033]

[0034] (Where Z 1 represents a hydrogen atom or a methyl group, Z 2 represents a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

[0035] <3>

[0036] As mentioned above <1> or <2> The polymer, wherein the unit B2 is represented by the following formula (B2-1).

[0037] [Chemical formula 6]

[0038]

[0039] (Where Z 1 represents a hydrogen atom or a methyl group, Q 1represents a single bond or an ether bond, a linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, which may have an unsaturated bond and may be substituted with a halogen, and W 1 represents an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond. 1 and W 1 At least one of them has one or more ether bonds.)

[0040] <4>

[0041] As mentioned above <1> ~ <3> The polymer described above has a weight average molecular weight of 100,000 to 400,000.

[0042] <5>

[0043] As mentioned above <1> ~ <4> The polymer described above has a glass transition temperature (Tg) of 20° C. or less.

[0044] <6>

[0045] A curable resin composition comprising:

[0046] Alkali soluble resin (A);

[0047] Polymer (B), the polymer (B) is the aforementioned <1> ~Foregoing <5> A polymer as described in any one of the preceding claims; and

[0048] Monofunctional monomer (C).

[0049] <7>

[0050] As mentioned above <6> The curable resin composition, wherein the alkali-soluble resin (A) is a copolymer comprising the following units: a unit (a-1) derived from a compound represented by the above formula (1); a unit (a-2) having a glass transition temperature of 70 to 200° C. when a homopolymer is prepared; and a unit (a-3) derived from an unsaturated compound containing an epoxy group.

[0051] <8>

[0052] As mentioned above <6> or <7> In the curable resin composition, the monofunctional monomer (C) is a monofunctional (meth)acrylate monomer which may have an ether bond in its structure.

[0053] <9>

[0054] As mentioned above <6> ~ <8> The curable resin composition described above further comprises a silane coupling agent.

[0055] <10>

[0056] As mentioned above <6> ~ <9> The curable resin composition according to any one of the above aspects is used for pattern formation.

[0057] <11>

[0058] The elongated insulating cured film is made of the above <6> ~ <10> Obtained by curing the curable resin composition described in any one of the above.

[0059] <12>

[0060] The insulating cured film for touch panel is made of the above <6> ~ <10> Obtained by curing the curable resin composition described in any one of the above.

[0061] <13>

[0062] A touch panel having the aforementioned <12> The insulating cured film for a touch panel.

[0063] <14>

[0064] An insulating cured film for a flexible printed circuit board, which is <6> ~ <10> Obtained by curing the curable resin composition described in any one of the above.

[0065] <15>

[0066] A flexible printed circuit substrate having the aforementioned <14> The insulating cured film for the flexible printed circuit substrate.

[0067] Effects of the Invention

[0068] According to the present invention, there can be provided a novel polymer and a curable resin composition capable of forming a cured film having excellent elongation, an elongated insulating cured film obtained by curing the composition, an insulating cured film for a touch panel, an insulating cured film for a touch panel, a flexible printed circuit board, and a flexible printed circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] [ Figure 1 ] is a top view showing the structure of one form of the touch panel of this embodiment.

[0070] [ Figure 2 ]for Figure 1 AA cross-section diagram in. DETAILED DESCRIPTION

[0071] Hereinafter, a method for implementing the present invention (hereinafter referred to as "this embodiment") is described in detail. However, the present invention is not limited thereto, and various modifications can be made without departing from the gist thereof. It should be noted that, throughout this specification, "(meth)acrylate" includes "acrylate" or "methacrylate".

[0072] <<Polymer (B) of this embodiment>>

[0073] The polymer of the present embodiment (hereinafter also referred to as "polymer (B)") is a polymer comprising the following units: unit B1 derived from a (meth)acrylic acid alkyl ester monomer (B1) containing a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen; unit B2 derived from a (meth)acrylic acid ester monomer (B2) having an ether bond; and unit B3 derived from a (meth)acrylic acid ester monomer (B3) represented by the following formula (1). Hereinafter, each (meth)acrylic acid ester monomer may be simply referred to as "monomer (B1)" or the like.

[0074] [Chemical formula 7]

[0075]

[0076] (In formula (1), R 1 represents a hydrogen atom or a methyl group. 2 is a hydrogen atom or a group selected from the groups represented by the following formula (2).

[0077] [Chemical formula 8]

[0078]

[0079] (In formula (2), X 1 R represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen. 3 is a group selected from the following formula (3) or the following formula (4).

[0080] [Chemical formula 9]

[0081]

[0082] (In formula (3), X 2 It represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

[0083] [Chemical formula 10]

[0084]

[0085] In formula (4), ring A represents a cyclic hydrocarbon group having 3 to 10 carbon atoms which may have an unsaturated bond, in which a part of the carbon atoms constituting the ring may be replaced by oxygen or nitrogen and which may have a substituent, or an aromatic group having 4 to 10 carbon atoms which may have a substituent. 4is a group selected from the group consisting of a linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms and a carboxyl group. n represents an integer greater than 1, and at least one R 4 is a carboxyl group.)

[0086] The polymer (B) of the present embodiment has elongation, and the polymer (B) and the material comprising the polymer (B) function as a telescopic material (elastomer), therefore, it can be preferably used in the field requiring softness and flexibility. In addition, the polymer (B) of the present embodiment can exert excellent insulation, therefore, it can also be preferably used in the field requiring insulation. In addition, the polymer (B) of the present embodiment has a tendency to be excellent in compatibility with the alkali-soluble resin (A) described later. Therefore, it can be applicable to the purposes requiring elongation, in addition, when making a curable resin composition, a high-precision pattern (for example, a through hole with a diameter of 25 μm, etc.) can be formed as required, and it can also contribute to the improvement of "patterning".

[0087] As described above, polymer (B) is a copolymer comprising at least unit B1 from (B1), unit B2 from (B2), and unit B3 from (B3). The copolymer of the present embodiment is not limited to the following copolymers, but can exert elongation due to unit B1, and can exert excellent insulation due to unit B3 containing an acidic group (carboxyl group). In addition, due to the ether bond of unit B2 and the acidic group of unit B3, there is a tendency to exert excellent compatibility with alkali-soluble resin (A).

[0088] (Unit B1)

[0089] Unit B1 is a unit derived from an alkyl (meth)acrylate monomer (B1) containing a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen. Monomer (B1) and unit B1 can be represented by the following formula (B1) and formula (B1-1), respectively, for example.

[0090] [Chemical formula 11]

[0091]

[0092] (Where Z 1 represents a hydrogen atom or a methyl group, Z 2 represents a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

[0093] [Chemical formula 12]

[0094]

[0095] (Where Z1 represents a hydrogen atom or a methyl group, Z 2 represents a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

[0096] In formula (B1) and (B1-1), Z 1 is a hydrogen atom or a methyl group. 1 Among them, a hydrogen atom is preferred from the viewpoint of easiness of polymerization and obtaining a (meth)acrylic elastomer having a low Young's modulus.

[0097] In formula (B1) and (B1-1), Z 2 It is a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with halogen. 2 The hydrocarbon group represented by is preferably 5 to 20 carbon atoms, preferably 5 to 18 carbon atoms, and more preferably 8 to 12 carbon atoms, from the viewpoint of elongation and compatibility with other components.

[0098] The linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms is not particularly limited, and examples thereof include n-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, isononyl, isodecyl, lauryl (dodecyl), cetyl, n-octadecyl, and isooctadecyl. From the viewpoint of elongation, a linear aliphatic hydrocarbon group is preferred, and n-octyl, n-nonyl, and lauryl are more preferred.

[0099] The aliphatic hydrocarbon group may have a halogen atom as a substituent. As the halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. may be cited. The number of halogen atoms included in the aliphatic hydrocarbon group varies depending on the number of carbon atoms of the aliphatic hydrocarbon group, etc., and therefore cannot be determined in general, so it is preferably appropriately adjusted within the scope of not hindering the purpose of the present embodiment.

[0100] Examples of the aliphatic hydrocarbon group having 5 to 20 carbon atoms and having a halogen atom include 2,2,3,3-tetrafluoropropyl, 1H,1H,5H,-octafluoropentyl, and 1H,1H,2H,2H-tridecafluorooctyl, but the present embodiment is not limited to these examples.

[0101] Examples of the aliphatic hydrocarbon group having 5 to 20 carbon atoms and having an unsaturated bond include agaryl, geranyl, neryl, and 2-(N-butylcarbamoyloxy)ethyl, but the present embodiment is not limited to these examples.

[0102] Examples of the monomer (B1) include n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, n-octadecyl (meth)acrylate, and isooctadecyl (meth)acrylate, with n-octyl acrylate and lauryl acrylate being preferred.

[0103] The polymer (B) may contain only one type of the unit (B1) or two or more types of the unit (B1).

[0104] (Unit B2)

[0105] Unit B2 is a unit derived from a (meth)acrylate monomer (B2) having an ether bond. Monomer (B2) and unit B2 can each be represented by, for example, the following formula (B2) and formula (B2-1).

[0106] [Chemical formula 13]

[0107]

[0108] (Where Z 1 represents a hydrogen atom or a methyl group, Q 1 represents a single bond or an ether bond, a linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, which may have an unsaturated bond and may be substituted with a halogen, and W 1 represents an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond. 1 and W 1 At least one of them has one or more ether bonds.)

[0109] [Chemical formula 14]

[0110]

[0111] (Where Z 1 represents a hydrogen atom or a methyl group, Q 1 represents a single bond or an ether bond, a linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, which may have an unsaturated bond and may be substituted with a halogen, and W 1 represents an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond. 1 and W 1 At least one of them has one or more ether bonds.)

[0112] In formula (B2) and (B2-1), Z 1 is a hydrogen atom or a methyl group. 1Among them, a hydrogen atom is preferred from the viewpoint of easiness of polymerization and obtaining a (meth)acrylic elastomer having a low Young's modulus.

[0113] In formula (B2) and (B2-1), Q 1 It is a single bond or ether bond, a linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, which may have an unsaturated bond and may be substituted with a halogen. 1 The number of carbon atoms of the hydrocarbon group represented is 1 to 10, preferably 2 to 6, and more preferably 2 to 4, from the viewpoint of compatibility with the alkali-soluble resin (A) and ease of development when used as a resist material.

[0114] The straight-chain, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is not particularly limited, and examples thereof include methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, tert-butylene, sec-butylene, n-pentylene, isopentylene, n-hexylene, isohexylene, cyclohexylene and n-octylene, but the present embodiment is not limited to these examples.

[0115] The aliphatic hydrocarbon group may have a halogen atom as a substituent. As the halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. may be cited. The number of halogen atoms included in the alkyl group varies depending on the number of carbon atoms of the alkyl group, and therefore cannot be determined in general, so it is preferably appropriately adjusted within the scope of not hindering the purpose of the present embodiment.

[0116] Examples of the divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms and having a halogen atom include difluoromethylene, tetrafluoroethylene, hexafluoro-n-propylene, hexafluoro-iso-propylene, octafluoro-n-butylene, octafluoro-iso-butylene, and octafluoro-tert-butylene. However, the present embodiment is not limited to these examples.

[0117] Examples of the divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms and having an unsaturated bond include a phenylene group, but the present embodiment is not limited to these examples.

[0118] Examples of the divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms and having an ether bond include polyoxyethylene groups such as oxyethylene and bisoxyethylene, and alkyl groups having a cyclic ether such as tetrahydrofuran, dioxolane, tetrahydropyran, and dioxane. From the viewpoint of ease of development and compatibility with the alkali-soluble resin (A), polyoxyethylene groups are preferred, and oxyethylene groups are more preferred.

[0119] As Q in formula (B2) and (B2-1) 1, preferably has 2 to 6 carbon atoms, and more preferably has 2 to 4 carbon atoms, from the viewpoint of compatibility with the alkali-soluble resin (A) and ease of development when used as a resist material. From the same viewpoint, Q in formula (B2) and (B2-1) is 1 , preferably a polyoxyethylene group, and more preferably an oxyethylene group.

[0120] In formula (B2) and (B2-1), W 1 represents an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond.

[0121] Examples of the aromatic group include a phenyl group, a biphenyl group, a naphthyl group, and a fluorenyl group, and a phenyl group is preferred. However, the present embodiment is not limited to these examples.

[0122] Examples of the cyclic aliphatic hydrocarbon group that may contain an ether bond include an epoxy group, a tetrahydrofurfuryl group, a 2-methyl-2-ethyl-1,3-dioxolan-4-yl group, a 3-ethyloxetane-3-yl group, and a 5-ethyl-1,3-dioxan-5-yl group. However, the present embodiment is not limited to these examples.

[0123] It should be noted that Q 1 and W 1 At least one of them is an ether bond.

[0124] Examples of the monomer (B2) include phenoxyethyl (meth)acrylate, phenoxybenzyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, ethoxylated o-phenylphenol (meth)acrylate, p-cumylphenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tetrahydrofurfuryl (THF) (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, and cyclic trimethylolpropane formal (meth)acrylate. From the viewpoint of elongation and compatibility, those having an aromatic organic group at the terminal are preferred, and for example, phenoxyethyl acrylate and phenoxybenzyl (meth)acrylate are preferred.

[0125] In the polymer (B), the units (B2) may be contained alone or in combination of two or more.

[0126] (Unit B3)

[0127] Unit B3 is a unit derived from a (meth)acrylate monomer (B3) represented by formula (1). Monomer (B3) is a (meth)acrylate monomer having a hydroxyl group or a carboxyl group, and has formula (1) as a main skeleton and R 2is a hydrogen atom or a group represented by formula (2). 3 A group represented by any one of formula (3) and formula (4). Each formula is described below.

[0128] -Formula (1)-

[0129] In the following formula (1), R 1 represents a hydrogen atom or a methyl group. 2 is a hydrogen atom or a group selected from the group represented by the following formula (2). 1 Among them, a hydrogen atom is preferred from the viewpoint of easiness of polymerization and obtaining a (meth)acrylic elastomer having a low Young's modulus.

[0130] [Chemical formula 15]

[0131]

[0132] -Formula (2) to (4)-

[0133] In the following formula (2), X 1 R represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen. 3 It is a group selected from the group consisting of the formula (3) described later or the formula (4) described below.

[0134] [Chemical formula 16]

[0135]

[0136] [Chemical formula 17]

[0137]

[0138] (In formula (3), X 2 It represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

[0139] [Chemical formula 18]

[0140]

[0141] In formula (4), ring A represents a cyclic hydrocarbon group having 3 to 10 carbon atoms which may have an unsaturated bond, in which a part of the carbon atoms constituting the ring may be replaced by oxygen or nitrogen and which may have a substituent, or an aromatic group having 4 to 10 carbon atoms which may have a substituent. 4 is a group selected from the group consisting of a linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms and a carboxyl group. n represents an integer greater than 1, and at least one R 4 is a carboxyl group.)

[0142] In formulas (2) to (3), X 1 To X 2 The number of carbon atoms of the linear or branched divalent aliphatic hydrocarbon group which may have an unsaturated bond and may be substituted with halogen is 1 to 5, preferably 2 to 4, and more preferably 2 to 3, from the viewpoint of obtaining a polymer (B) having a low Young's modulus.

[0143] The linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms is not particularly limited, and examples thereof include methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, tert-butylene, sec-butylene, and n-pentylene. From the viewpoint of obtaining a (meth)acrylic elastomer having a low Young's modulus, ethylene and butylene are preferred, and ethylene is more preferred.

[0144] Examples of the linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms and having a halogen atom include a difluoromethylene group and a tetrafluoroethylene group, but the present embodiment is not limited to these examples.

[0145] Examples of the linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms and having an unsaturated bond include vinylene groups, but the present embodiment is not limited to these examples.

[0146] In formula (4), ring A represents a cyclic hydrocarbon group having 3 to 10 carbon atoms which may have an unsaturated bond, in which a part of the carbon atoms constituting the ring may be replaced by oxygen and nitrogen, and which may have a substituent, or an aromatic group having 4 to 10 carbon atoms which may have a substituent. The number of carbon atoms in the cyclic hydrocarbon group is 3 to 10, preferably 4 to 8, and more preferably 4 to 6, from the viewpoint of easiness of development and improvement of the hydrophobicity of the cured film. Similarly, the number of carbon atoms in the aromatic group is 4 to 10, preferably 6 to 10, from the viewpoint of easiness of development when used as a resist material and improvement of the hydrophobicity when used as a cured film.

[0147] Examples of the cyclic hydrocarbon group having 3 to 10 carbon atoms include a cyclopropane ring, a cyclohexane ring, a cyclohexene ring, a norbornane ring, and a norbornene ring, but the present embodiment is not limited to these examples.

[0148] In addition, examples of the aromatic group having 4 to 10 carbon atoms include a benzene ring, a naphthalene ring, and an azulene ring, but the present embodiment is not limited to these examples.

[0149] Ring A is not particularly limited, but is preferably a cyclic hydrocarbon group having 4 to 10 carbon atoms, and more preferably a cyclohexane ring, from the viewpoint of easiness of development when used as a resist material and improvement of hydrophobicity when used as a cured film.

[0150] In formula (4), R 4 It is a group selected from the group consisting of a linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms and a carboxyl group. As for the carbon number of the linear or branched aliphatic hydrocarbon group, the carbon number is 1 to 5, preferably 1 to 4, and more preferably 1 to 2. In addition, n is 1 or more, and the upper limit of n can be determined according to the structure of ring A. The range of n is not particularly limited, but for example, from the viewpoint of the ease of development when made into a resist material and the improvement of hydrophobicity when made into a cured film, it is preferably 1 to 4, and more preferably 1 to 2.

[0151] Examples of the linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms include a methyl group and an ethyl group, but the present embodiment is not limited to these examples.

[0152] Examples of the monomer (B3) include the following compounds. 1 It is a hydrogen atom or a methyl group. From the viewpoint of easiness of development and improvement of the hydrophobicity of the cured film, acrylic acid and 2-((carboxycyclohexylcarbonyl)oxyethyl acrylate are preferred, and acrylic acid is more preferred. It should be noted that in the following compounds, the hydrogen atom on the ester side may be substituted by a halogen.

[0153] In the polymer (B), the units (B3) may be contained alone or in combination of two or more.

[0154] [Chemical formula 19]

[0155]

[0156] (Composition ratio)

[0157] Regarding the content (mol %) of unit B1, unit B2 and unit B3 in the aforementioned polymer (B), from the viewpoint of having excellent elongation and insulation properties, preferably unit B1 / unit B2 / unit B3 = 10 to 50 / 5 to 50 / 15 to 45, more preferably 15 to 45 / 10 to 45 / 20 to 40, and particularly preferably 20 to 40 / 20 to 40 / 30 to 40.

[0158] (Other structural units)

[0159] The polymer (B) may contain other structural units that do not belong to any of the above-mentioned units B1 to B3. Examples of other structural units include derivatized styrene and derivatized maleimide.

[0160] The content (mol %) of other structural units in the polymer (B) is preferably 0 to 30 mol %, more preferably 0 to 20 mol %, from the viewpoint of excellent elongation and insulation properties.

[0161] (Molecular weight)

[0162] From the viewpoint of excellent elongation, compatibility with the alkali-soluble resin (A), and insulation reliability, the weight average molecular weight of the polymer (B) is preferably 100,000 to 400,000, more preferably 150,000 to 350,000, and particularly preferably 200,000 to 250,000. The molecular weight of the polymer (B) can be measured by gel permeation chromatography (manufactured by TOSOH Corporation, product number: HLC-8320, column: 2 TSKgel GMHHR-H (30) connected, detector: RI, mobile phase: tetrahydrofuran).

[0163] (Glass transition temperature)

[0164] From the viewpoint of elongation, the glass transition temperature of the polymer (B) is preferably 20° C. or less, more preferably -45° C. to 20° C., further preferably -40° C. to 15° C., and particularly preferably -30° C. to 10° C. The glass transition temperature can be obtained by the so-called "FOX equation" based on the Tg of each monomer unit constituting the polymer (B) when it is made into a homopolymer, and the value described in the literature can be used, and the Tg when each monomer unit is made into a homopolymer can adopt a known value, for example, described in "POLYMER HANDBOOK 3rd Edition" (published by John Wiley & Sons, Inc.) and the like.

[0165] (specific example)

[0166] Specific examples of the polymer (B) include the following polymers.

[0167] [Table 1]

[0168] B1 B2 B3 Ba n-Octyl acrylate Phenoxyethyl acrylate acrylic acid Bb Lauryl acrylate Phenoxyethyl acrylate acrylic acid

[0169] (Synthesis Method)

[0170] The polymer (B) is not particularly limited and can be synthesized by mixing the units B1 to B3 at a desired composition ratio and heating or irradiating the mixture with light in the presence of a polymerization initiator.

[0171] 《Curable resin composition》

[0172] The curable resin composition of the present embodiment (hereinafter also referred to as "the composition of the present invention") comprises an alkali-soluble resin (A), the above-mentioned polymer (B) and a monofunctional monomer (C). The curable resin composition of the present embodiment can be cured to form a cured film (including the case of forming a pattern), and a conductive pattern, etc., can be formed on the cured film. The cured film of the present embodiment can be used as an extensible and soft film, for example, when a conductive pattern with extensibility is formed for a bendable substrate, a soft electrode, etc., it can also exert extensibility, and the insulation is also excellent.

[0173] <Alkali-soluble resin (A)>

[0174] In the present embodiment, the alkali-soluble resin (A) is not particularly limited, but is preferably a copolymer comprising the following units: a unit (a-1) derived from a compound represented by the aforementioned formula (1); a unit (a-2) having a glass transition temperature of 70 to 200°C in the case of a homopolymer; and a unit (a-3) derived from an unsaturated compound containing an epoxy group. By making the curable resin composition contain an alkali-soluble resin (A), the hydrophobicity and even the insulation reliability of the obtained cured film can be improved. The alkali-soluble resin (A) may contain one type of each of the structural units (a-1), (a-2) and (a-3), or may contain two or more of the same structural units (for example, containing two types of structural units (a-2)). Although not particularly limited, if a copolymer containing the structural units (a-1), (a-2) and (a-3) is used as the alkali-soluble resin (A), the hydrophobicity, insulation reliability and pattern forming properties of the obtained cured product can be improved.

[0175] (Structural unit (a-1))

[0176] The structural unit (a-1) is a unit derived from the compound represented by the formula (1) in the above unit B3. The compound represented by the formula (1) is a (meth)acrylate monomer having a carboxyl group, and has the above formula (1) as the main skeleton and R 2 is a hydrogen atom or a group represented by the above formula (2). 3 A group represented by any one of the above formulae (3) and (4). It should be noted that, in terms of the structural unit (a-1), from the viewpoint of the pattern forming property and hydrophobicity of the cured product, R in the formula (1) 1 Preferred is methyl.

[0177] Examples of the structural unit (a-1) include carboxyl group-containing monomers such as o-, m-, and p-vinylbenzoic acid, maleic acid, maleic anhydride, fumaric acid, fumaric anhydride, citraconic acid, mesaconic acid, itaconic acid, crotonic acid, (meth)acryloyloxyethyl monosuccinate, (meth)acryloyloxyethyl monotetrahydrophthalate, (meth)acrylic acid, (meth)acryloylethyl monophthalate, (meth)acryloylethyl monohexahydrophthalate, (meth)acryloylethyl monotetrahydrophthalate, (meth)acryloyloxyethyl monophthalate, (meth)acryloyloxyethyl monohexahydrophthalate, and caprolactone adducts of (meth)acrylic acid.

[0178] Among them, carboxyl group-containing monomers such as (meth)acrylic acid, (meth)acryloylethyl monophthalate, (meth)acryloylethyl monohexahydrophthalate, (meth)acryloylethyl monotetrahydrophthalate, and caprolactone adducts of (meth)acrylic acid are preferably used.

[0179] Furthermore, two or more of the above monomers may be used.

[0180] (Structural unit (a-2))

[0181] The structural unit (a-2) is a structural unit having a glass transition temperature (Tg) (hereinafter, sometimes referred to as "the glass transition temperature of the structural unit (a-2)") of 70 to 200°C when it is made into a homopolymer and having a structure different from that of the structural units (a-1) and (a-3). If the glass transition temperature of the structural unit (a-2) is 70°C or higher, the water resistance becomes good, and if it is 200°C or lower, the developability is excellent. The alkali-soluble resin (A) preferably contains a structural unit (a-2) having a glass transition temperature of 80 to 200°C when it is made into a homopolymer. In addition, the glass transition temperature of the structural unit (a-2) is further preferably 80 to 180°C, and most preferably 100 to 180°C. The glass transition temperature can use a value described in the literature, for example, described in "POLYMER HANDBOOK 3rd Edition" (published by John Wiley & Sons, Inc.) and the like.

[0182] The structural unit (a-2) has no particular problem as long as it satisfies the above conditions, but preferably used are, for example, 4-biphenyl methacrylate (100°C), 2-naphthyl methacrylate (85°C), 3,5-dimethyladamantyl crotonate (159°C), methyl methacrylate (105°C), 1,1-dimethylethyl methacrylate (118°C), 1-methylethyl methacrylate (81°C), isobornyl methacrylate (110°C), phenyl methacrylate (110°C), methacrylate (110°C), (Meth) acrylic acid monomers such as adamantyl ester (141°C), 4-(1,1-dimethylethyl)cyclohexyl methacrylate (83°C), 4-(1,1-dimethylethyl)phenyl methacrylate (98°C), 3,3-dimethyl-1-butyl methacrylate (108°C), 3,3,5-trimethylhexyl methacrylate (125°C), 2,3-xylyl methacrylate (125°C), dicyclopentyl methacrylate (175°C), and 3,5-dimethyladamantyl methacrylate (196°C). It should be noted that the temperature in parentheses following the compound name represents the glass transition temperature of each compound. It should be noted that this value is a literature value.

[0183] Among them, dicyclopentyl (meth)acrylate and 3,5-dimethyladamantyl (meth)acrylate are preferably used from the viewpoint of easiness of polymerization (hereinafter referred to as polymerizability) with each structural unit (including structural unit a-1 and structural unit a-3) and improvement of the hydrophobicity of the cured product.

[0184] Furthermore, two or more of the above monomers may be used.

[0185] (Structural unit (a-3))

[0186] The structural unit (a-3) is a structural unit derived from an unsaturated compound containing an epoxy group. As the structural unit derived from an unsaturated compound containing an epoxy group, one can be appropriately selected from unsaturated compounds containing epoxy groups (or structural units derived therefrom) conventionally used in various photosensitive resin compositions.

[0187] Examples of the unsaturated compound containing an epoxy group include unsaturated compounds having an epoxy structure such as an alicyclic epoxy group in a ring structure and unsaturated compounds not having an alicyclic epoxy group. Unsaturated compounds having an epoxy structure such as an alicyclic epoxy group in a ring structure are preferred.

[0188] As the unsaturated compound having an alicyclic epoxy group, the alicyclic group constituting the alicyclic epoxy group may be monocyclic or polycyclic. As the monocyclic alicyclic group, for example, cyclopentyl, cyclohexyl, etc. may be mentioned. In addition, as the polycyclic alicyclic group, for example, norbornyl, isobornyl, tricyclononyl, tricyclodecyl, tetracyclododecyl, etc. may be mentioned.

[0189] Examples of the unsaturated compound having an epoxy group include unsaturated compounds containing an epoxy group described in paragraphs 0015 to 0024 of JP-A-2013-228662. Specifically, glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, and 3,4-epoxycyclohexylmethyl methacrylate are preferred. From the viewpoint of chemical resistance, 3,4-epoxycyclohexylmethyl methacrylate is more preferred.

[0190] Furthermore, two or more of the above monomers may be used.

[0191] (Composition ratio)

[0192] With regard to the content (mol %) of the aforementioned structural unit (a-1), the aforementioned structural unit (a-2) and the aforementioned structural unit (a-3) in the aforementioned alkali-soluble resin (A), from the viewpoint of achieving both elongation and insulation reliability, preferably (a-1) / (a-2) / (a-3)=10 to 40 / 30 to 65 / 15 to 50, and more preferably 15 to 35 / 25 to 60 / 20 to 40.

[0193] (Other structural units)

[0194] The alkali-soluble resin (A) may contain other structural units that do not belong to any of the structural units (a-1) to (a-3). Examples of other structural units include benzyl methacrylate, 1,3-bis(methacryloyloxy)-2-propanol, 2-methacryloyloxyethyl isocyanate, and 2-hydroxyethyl methacrylate.

[0195] From the viewpoint of achieving both elongation and insulation reliability, the content (mol %) of other structural units in the alkali-soluble resin (A) is preferably 0 to 20 mol %, more preferably 0 to 10 mol %.

[0196] (Molecular weight)

[0197] The weight average molecular weight of the alkali-soluble resin (A) is preferably 4,000 to 15,000, more preferably 5,000 to 12,000, and particularly preferably 5,500 to 10,000. The molecular weight of the alkali-soluble resin (A) can be measured by gel permeation chromatography (manufactured by TOSOH Corporation, product number: HLC-8320, column: G-5000HXL and G-3000HXL connected, detector: RI, mobile phase: tetrahydrofuran).

[0198] (Glass transition temperature)

[0199] From the viewpoint of insulation reliability, the glass transition temperature of the alkali-soluble resin (A) is preferably 50 to 200° C., more preferably 70 to 170° C., and particularly preferably 80 to 140° C. The glass transition temperature can be measured by a differential scanning calorimeter (DSC).

[0200] (specific example)

[0201] Specific examples of the alkali-soluble resin (A) include the following polymers: In addition, A3 in the following table contains benzyl methacrylate as another structural unit.

[0202] [Table 2]

[0203]

[0204] (content)

[0205] The content of the alkali-soluble resin (A) in the curable resin composition of the present embodiment is not particularly limited, but for example, from the viewpoint of insulation, it is preferably 5 to 80% by mass, more preferably 10 to 70% by mass, and particularly preferably 15 to 60% by mass relative to the total solid content in the composition. Throughout this specification, the so-called "total solid content" refers to all components in the resin composition except the solvent.

[0206] <Polymer (B)>

[0207] From the viewpoint of maintaining insulation and improving elongation, the curable resin composition of the present embodiment includes the above-mentioned polymer (B). The preferred embodiment of the polymer (B) included in the curable resin composition of the present embodiment is the same as the preferred range and preferred physical properties of each unit in the description of the above-mentioned polymer (B).

[0208] The content of the polymer (B) in the curable resin composition of the present embodiment is not particularly limited, but is preferably 50 to 400 parts by mass, more preferably 70 to 300 parts by mass, and particularly preferably 80 to 200 parts by mass, relative to 100 parts by mass of the alkali-soluble resin (A), from the viewpoints of elongation, transparency, and pattern properties.

[0209] <Other polymers>

[0210] The curable resin composition of the present embodiment may contain other polymers in addition to the alkali-soluble resin (A) and the polymer (B). The other polymers are not particularly limited, and examples thereof include polymers containing any two of the above-mentioned structural units (a-1) to (a-3).

[0211] The curable resin composition of the present embodiment may be formed as follows: in the curable resin composition of the present embodiment, only the alkali-soluble resin (A) and the polymer (B) are included as polymers. When other polymers are used, the content of the other polymers is not particularly limited, but for example, from the viewpoint of not greatly inhibiting the chemical resistance of the cured film and obtaining the effect brought about by including the other polymers, the content is preferably 10 to 400 parts by mass, and more preferably 20 to 300 parts by mass, relative to 100 parts by mass of the alkali-soluble resin (A).

[0212] <Monofunctional Monomer (C)>

[0213] The curable resin composition of the present embodiment includes a monofunctional monomer. Here, the so-called "monofunctional monomer" refers to a compound having only one functional group. If a monofunctional monomer is used, it can be imagined that the monomer (C) is mainly polymerized between the monomers (C) during the photocuring of the composition. Therefore, the ratio of monomer (C) to other polymer bonds is low, and compared with the case where a multifunctional monomer is used, the elongation of the cured product can be improved.

[0214] As a functional group of a monomer (C), a (meth)acrylate group etc. are mentioned, for example.

[0215] The molecular weight of the monofunctional monomer is not particularly limited, but is, for example, more preferably 80 to 420, and particularly preferably 120 to 220, from the viewpoint of developability and insulation reliability.

[0216] In addition, as the monofunctional monomer, from the viewpoint of improving pattern properties, a monofunctional (meth)acrylate monomer which may have an ether bond in the structure is preferred.

[0217] As the monofunctional (meth)acrylate monomer which may have an ether bond in the structure, for example, a (meth)acrylate monomer represented by the following formula (C-1) can be used.

[0218] [Chemical formula 20]

[0219]

[0220] (Where Z 3 represents a hydrogen atom or a methyl group, Q 3 represents a linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a single bond or an ether bond and may be substituted with halogen, W 3 represents a hydrogen atom, an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond. )

[0221] In formula (C-1), Z 3 is a hydrogen atom or a methyl group. 3 Among them, a hydrogen atom is preferred from the viewpoint of easiness of polymerization and obtaining a cured film having a low Young's modulus.

[0222] In formula (C-1), Q 3 It is a straight-chain, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a single bond or an ether bond. 3 The number of carbon atoms of the hydrocarbon group represented is 1 to 10, preferably 1 to 6, and more preferably 2 to 4, from the viewpoint of developability.

[0223] The linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is not particularly limited, and examples thereof include methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, tert-butylene, sec-butylene, n-pentylene, isopentylene, n-hexylene, isohexylene, cyclohexylene and n-octylene. From the viewpoint of developability, methylene and ethylene are preferred, and ethylene is more preferred.

[0224] Examples of the divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms and having an ether bond include linear oxyalkylene chains such as methoxyethyl acrylate, and alkyl groups having cyclic ethers such as tetrahydrofuran, dioxolane, tetrahydropyran, and dioxane. However, the present embodiment is not limited to these examples.

[0225] In formula (C-1), W 3 represents a hydrogen atom, an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond.

[0226] Examples of the aromatic group include a phenyl group, a biphenyl group, a naphthyl group, and a fluorenyl group, and a phenyl group is preferred. However, the present embodiment is not limited to these examples.

[0227] Examples of the cyclic aliphatic hydrocarbon group which may contain an ether bond include tetrahydrofuran, dioxolane, tetrahydropyran, and dioxane, and tetrahydrofuran is preferred. However, the present embodiment is not limited to these examples.

[0228] Examples of the monomer (C) include dicyclopentenyloxyethyl acrylate, o-phenoxybenzyl acrylate, ethoxylated o-phenylphenol acrylate, phenoxyethyl acrylate, and 1H,1H,5H-octafluoropentyl acrylate.

[0229] The content of the monomer (C) in the curable resin composition of the present embodiment is not particularly limited, but for example, from the viewpoint of developability and insulation properties, it is preferably 5 to 300 parts by mass, more preferably 50 to 250 parts by mass, and particularly preferably 100 to 200 parts by mass, relative to 100 parts by mass of the alkali-soluble resin (A).

[0230] In addition, the curable resin composition of the present embodiment may contain other monomers that react due to light or heat in addition to the above-mentioned compounds. As other monomers, there are no particular limitations, and for example, compounds having three or more ethylenically unsaturated groups in the molecule can be cited. As examples of such compounds, for example, trimethylolpropane triacrylate, pentaerythritol triacrylate, etc. can be cited.

[0231] When the curable resin composition of the present embodiment contains monomer (C) and other monomers, the content of monomer (C) relative to the total amount of photoreactive monomers in the composition is preferably 75% by mass or more, and more preferably 80% by mass or more, from the viewpoint of elongation.

[0232] <Preferred combination>

[0233] As an example of a preferred combination of an alkali-soluble resin (A), a polymer (B) and a monofunctional monomer (C), for example, a combination of an alkali-soluble resin (A) (a copolymer of structural unit (a-1): methacrylic acid, structural unit (a-2): dicyclopentyl methacrylate, and structural unit (a-3): 3,4-epoxycyclohexylmethyl methacrylate), a polymer (B) (at least one selected from the above-mentioned polymers Ba and Bb) and a monofunctional monomer (C) (at least one selected from the group consisting of dicyclopentenyloxyethyl acrylate, ethoxylated o-phenylphenol acrylate and 1H,1H,5H-octafluoropentyl acrylate).

[0234] (Polymerization initiator)

[0235] The curable resin composition of the present embodiment may contain a polymerization initiator. Examples of the polymerization initiator include photopolymerization initiators and thermal polymerization initiators. Among these polymerization initiators, photopolymerization initiators are preferred from the viewpoint of preventing thermal history from remaining in the polymer.

[0236] -Photopolymerization initiator-

[0237] Photopolymerization initiators are compounds that are activated by various active light rays, such as ultraviolet rays, and initiate polymerization. As photopolymerization initiators, for example, free radical photopolymerization initiators, cationic photopolymerization initiators, and anionic photopolymerization initiators can be cited. These photopolymerization initiators can be used alone or in combination of two or more. For example, two or more free radical photopolymerization initiators can be used in combination.

[0238] As a radical photopolymerization initiator, the following compounds are mentioned, for example.

[0239] You can use:

[0240] Acylphosphine oxide compounds: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name: IRGACURE TPO, manufactured by BASF), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (product name: IRGACURE 819, manufactured by BASF; product name: IRGACURE 819DW, manufactured by BASF)

[0241] α-Hydroxyketone compounds: 1-hydroxycyclohexyl phenyl ketone (product name: IRGACURE 184, manufactured by BASF), 2-hydroxy-2-methyl-1-phenylpropane-1-one (product name: IRGACURE 1173, manufactured by BASF), 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one (IRGACURE 2959, manufactured by BASF), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropanoyl)benzyl]phenyl}-2-methylpropane-1-one (product name: IRGACURE 127, manufactured by BASF)

[0242] Intramolecular hydrogen abstraction compound: methyl benzoylformate (product name: IRGACURE MBF, manufactured by BASF)

[0243] Titanocene compound-based compounds: 1-[4-(phenylthio)-2-(o-benzoyl oxime)], bis(η5-2,4-cyclopentadien-1-yl)bis[2,6-difluoro-3-(1H-pyrrol-1-yl)phenyltitanium] (product name: IRGACURE 784, manufactured by BASF)

[0244] Benzil ketal compound: 2,2-dimethoxy-1,2-diphenylethane-1-one (product name: IRGACURE 651, manufactured by BASF)

[0245] α-Aminoketone compounds: 2-methyl-4'-methylthio-2-morpholinopropiophenone (product name: IRGACURE 907, manufactured by BASF), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone (product name: IRGACURE 369, manufactured by BASF), 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholino)phenyl]-1-butanone (product name: IRGACURE 379EG, manufactured by BASF)

[0246] Oxime ester compounds: 1-[4-(phenylthio)-2-(O-benzoyloxime)] (product name: IRGACURE OXE-01, manufactured by BASF), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime) (for example, product name: IRGACURE OXE-02, manufactured by BASF; product name: IRGACURE OXE-03, manufactured by BASF; product name: IRGACURE OXE-04, manufactured by BASF; product name: N-1919, manufactured by ADEKA; product name: N-1414, manufactured by ADEKA), etc.

[0247] As other free radical photopolymerization initiators, for example, quinone compounds (for example, 2-ethylanthraquinone, 2-tert-butylanthraquinone); aromatic ketones (for example, benzophenone, benzoin); benzoin ether compounds (for example, benzoin methyl ether, benzoin ethyl ether); acridine compounds (for example, 9-phenylacridine (product name: N-1717, manufactured by ADEKA)); triazine compounds (for example, 2,4-trichloromethyl-(4″-methoxyphenyl)-6-triazine, 2,4-trichloromethyl-(4′-methoxynaphthyl)-6-triazine, 2,4-trichloromethyl-(piperonyl)-6-triazine, 2,4-trichloromethyl-(4′-methoxyphenyl)-6-triazine-2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one), etc. can be mentioned.

[0248] Examples of the cationic photopolymerization initiator include the following compounds.

[0249] Ionium salt compounds: diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphate, 4,4'-di-tert-butyldiphenyliodonium tetrafluoroborate, (4-methylphenyl)[4-(2-methylpropyl)phenyl]iodonium hexafluorophosphate (product name: IRGACURE 250, manufactured by BASF)

[0250] Diazonium salt compounds: 4-diethylaminophenylbenzenediazonium hexafluorophosphate,

[0251] Sulfonium salt compounds: diphenyl-4-phenylthiophenylsulfonium hexafluorophosphate, triarylsulfonium tetrakis(pentafluorophenyl)borate (product name: IRGACURE 290, manufactured by BASF), triarylsulfonium hexafluorophosphate (for example, product name: IRGACURE 270, manufactured by BASF; product name: CPI300, manufactured by Sanyo Chemical Industries, Ltd.; product name: CPI400, manufactured by Sanyo Chemical Industries, Ltd.),

[0252] Ferrocenium salt compounds

[0253] Examples of the anionic photopolymerization initiator include 1,5,7-triazabicyclo[4.4.0]dec-5-ene-2-(9-oxoxanthene-2-yl)propanoate.

[0254] In addition, a photosensitizer may be used together with the photopolymerization initiator. As the photosensitizer, for example, 4-dimethylaminobenzoic acid ethyl ester (DAROCUR EDB: manufactured by BASF) and 4-dimethylaminobenzoic acid 2-ethylhexyl ester (DAROCUR EHA: manufactured by BASF) as amines, and benzophenones, thioxanthones, keto-coumarins, and anthraquinones (ANTHRACURE UVS-581: manufactured by Kawasaki Chemical Industries) as ketone compounds may be used.

[0255] -Thermal polymerization initiator-

[0256] As the thermal polymerization initiator, for example, 2,2'-azobis(2-methylpropionic acid) dimethyl ester, 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobisisobutyric acid dimethyl ester, azobisdimethylvaleronitrile and other azo-based polymerization initiators, benzoyl peroxide, potassium persulfate, ammonium persulfate and other peroxide-based polymerization initiators can be cited, but the present embodiment is not limited to the above examples. These polymerization initiators can be used alone or in combination of two or more.

[0257] The content of the initiator in the curable resin composition of the present embodiment is not particularly limited, but is preferably 5 to 80 parts by mass, more preferably 15 to 40 parts by mass, based on 100 parts by mass of the alkali-soluble resin A, from the viewpoint of reactivity and storage stability.

[0258] (Silane coupling agent)

[0259] From the viewpoint of improving the adhesion between the substrate and the coating film, the curable resin composition of the present embodiment may use a silane coupling agent or the like. In addition, when the curable resin composition of the present embodiment contains a silane coupling agent, the insulating properties of the obtained cured product can be improved.

[0260] The type of silane coupling agent is not particularly limited, and a known silane coupling agent can be used, for example, 3-methacryloxypropyltrimethoxysilane (hereinafter D-1), a silane coupling agent containing a benzotriazole group (hereinafter D-2, N-phenyl-3-aminopropyltrimethoxysilane (hereinafter D-3) and a compound described in International Publication WO2014 / 104195 (for example, hereinafter D-4) can be used. Among them, from the viewpoint of improving insulation properties, it is preferred to use a silane coupling agent that does not have a hydrophilic group, for example, preferably the following D-2 to D-4.

[0261] [Chemical formula 21]

[0262]

[0263] The amount of the silane coupling agent in the curable resin composition of the present embodiment is not particularly limited, but is preferably 5 to 40 parts by mass, more preferably 10 to 30 parts by mass, relative to 100 parts by mass of the alkali-soluble resin A, from the viewpoint of improving adhesion to the substrate and insulation properties.

[0264] (Chain transfer agent)

[0265] When the monomer components in the present embodiment are polymerized, a chain transfer agent may be used to adjust the molecular weight of the obtained (meth) acrylic elastomer. As chain transfer agents, for example, compounds having a thiol group such as lauryl mercaptan, dodecyl mercaptan, and thioglycerol; inorganic salts such as sodium hypophosphite and sodium bisulfite; organic solvents such as toluene and cyclopentanone, etc., but the present embodiment is not limited to the examples. These chain transfer agents may be used alone or in combination of two or more. The amount of the chain transfer agent varies depending on the type of the chain transfer agent, etc., and therefore cannot be determined in general. Generally, it is preferably about 0.01 to 100 parts by mass relative to 100 parts by mass of the monomer component.

[0266] The content of the photopolymerization initiator in the curable resin composition of the present embodiment is not particularly limited, but is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, and particularly preferably 2 to 15 parts by mass, relative to 100 parts by mass of the alkali-soluble resin (A), from the viewpoint of photoreactivity and storage stability.

[0267] <Method for Preparing Curable Resin Composition>

[0268] The curable resin composition of the present embodiment contains an alkali-soluble resin (A), a polymer (B), and a monomer (C), and can be prepared by stirring and mixing the above-mentioned polymerization initiator, the following solvent, and the like.

[0269] (Solvent)

[0270] In the present embodiment, the solvent can be appropriately selected from known solvents according to the intended purpose.

[0271] Examples of the solvent include cyclopentanone, diethylene glycol ethyl methyl ether, acetylacetone, methanol, ethanol, ethyl cellosolve, ethyl cellosolve acetate, methyl cellosolve, methyl cellosolve acetate, diethylene glycol dimethyl ether, cyclohexanone, ethylbenzene, xylene, isoamyl acetate, n-amyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether ethyl Acid esters, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether, triethylene glycol monoethyl ether acetate, liquid polyethylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoethyl ether acetate, lactic acid esters, methyl methoxypropionate, ethyl ethoxypropionate, etc.

[0272] The above solvents may be used alone or in combination of two or more.

[0273] In addition, the content of the solvent in the curable resin composition of the present embodiment is not particularly limited, but for example, from the viewpoint of storage stability and coating properties, it is preferred to use the solvent in a manner where the total solid content (the total mass of the components in the composition excluding the solvent) concentration is preferably 1 to 40 mass %, further preferably 5 to 40 mass %, and particularly preferably 10 to 30 mass %. By making the solid content ratio within the above range, the viscosity of the curable resin composition can be moderate, and the coating properties when applied to a substrate, etc. to form a film are particularly improved.

[0274] In addition, the curable resin composition of the present embodiment can also use various additives such as inorganic fine particles, adhesion promoting additives, surfactants, storage stabilizers, leveling agents, light stabilizers, antioxidants, ultraviolet absorbers as needed. As examples of these additives, for example, the additives described in Japanese Patent Publication No. 2012-215833 can be cited.

[0275] 《Elongation insulating cured film》

[0276] The application of the curable resin composition of the present embodiment is not particularly limited, and for example, it can be used for pattern formation of insulating portions of electronic circuits, especially insulating portions of electronic circuits that require elongation and insulation such as bending or folding. Such applications include elongation insulating cured films, insulating cured films for touch panels, and the like. In addition, the elongation insulating cured film of the present embodiment has excellent softness and elongation, and therefore can be preferably used as a flexible sheet or a stretchable sheet.

[0277] The insulating cured film can be formed by various imparting methods such as spin coating such as spin coating, casting coating such as die coating, coating based on roller coating, coating based on roller transfer method, etc., using a curable resin composition to form a coating on a substrate such as a glass substrate, ITO, a metal film, an organic film, etc., and solidify the coating. Specifically, the curable resin composition can be applied to a substrate such as a glass substrate, irradiated with light to cure it, thereby forming a cured film of the present embodiment. In addition, light can be irradiated through a mask, and after development, heat treatment can be performed as needed, thereby patterning the cured film of the present embodiment.

[0278] The thickness of the elongated insulating cured film of this embodiment varies depending on the application and is not particularly limited, but is preferably about 10 μm to 5 mm, more preferably 500 μm or less, and particularly preferably 100 μm or less from the viewpoint of obtaining a cured film that achieves both high elongation and low hysteresis.

[0279] The Young's modulus, maximum point stress, and elongation of the elongated insulating cured film of the present embodiment can be measured, for example, using a tensile tester according to the method described in the examples described later.

[0280] From the viewpoint of flexibility, the Young's modulus of the elongation insulating cured film of the present embodiment is preferably about 5 GPa or less, more preferably 1 GPa or less, and particularly preferably 500 MPa or less.

[0281] From the viewpoint of toughness and handleability, the maximum point stress of the elongation insulating cured film of the present embodiment is preferably 1 MPa or more, more preferably 5 MPa or more, and particularly preferably 10 MPa or more.

[0282] From the viewpoint of stretchability and elongation, the elongation of the elongatable insulating cured film of the present embodiment is preferably 1% or more, more preferably 5% or more, and particularly preferably 10% or more.

[0283] As described above, the insulating cured film can be used for any purpose such as insulating film, protective film, flat film, etc. The insulating cured film using the curable resin composition of the present embodiment is not particularly limited, and can be preferably used as a protective film for a touch panel that requires elongation in order to exert softness and flexibility, an insulating film for a touch panel, and an insulating cured film for a flexible printed circuit board used in a flexible printed circuit board.

[0284] The stretchable insulating cured film of the present embodiment can be used not only as a so-called permanent film maintained in a device such as a touch panel, but also as a resist film used when patterning a conductive pattern on a substrate.

[0285] Touch Panel

[0286] As described above, the curable resin composition of the present embodiment and the insulating cured film using the same can be preferably used as an insulating film for touch panels. Hereinafter, the elongated insulating cured film and the insulating film for touch panels of the present embodiment are sometimes collectively referred to as "the cured film of the present embodiment". In the case of the use of the insulating film, the conductive pattern is sometimes formed on the cured film by a stripping method, and the subsequent liquid treatment is implemented. In the case of the cured film of the present embodiment, even after such treatment, the cured film will not be invaded by the liquid, and the transparency is not easily hindered. In addition, the cured film of the present embodiment has flexibility, so it can be preferably used as a member of a so-called flexible display that can be bent. In particular, the cured film of the present embodiment also suppresses the degradation of transparency associated with repeated bending. In addition, even in a display that is not a flexible display (for example, a flat non-flexible panel, a curved display, etc.), by using the insulating film of the present embodiment with elongation, it is also possible to impart resistance to bending, etc.

[0287] The touch panel of this embodiment can be any of a resistive film method, an electrostatic capacitance method, an ultrasonic method, and an optical method. The electrostatic capacitance touch panel uses a substrate formed with a conductive pattern, and in order to prevent misidentification of the contacted position, an insulating film and a protective film are provided in the laminated structure (for example, between electrodes). In the case where the touch panel of this embodiment is an electrostatic capacitance touch panel, the touch panel of this embodiment can use the cured film of this embodiment for example as an insulating film, a protective film, or both in the laminated structure.

[0288] The touch panel can be divided into a double-sided structure in which X electrodes are arranged on one side of an insulating film and Y electrodes are arranged on the other side, and a single-sided structure in which X electrodes and Y electrodes are formed on the same plane. The touch panel of this embodiment can be either a double-sided structure or a single-sided structure.

[0289] In a single-sided touch panel structure, the X electrode and the Y electrode are electrically separated. At this time, according to the pattern of the electrode, it can be distinguished into, for example, an island pattern, a through-hole pattern, etc. For example, in the case of an island pattern, in addition, in a single-sided touch panel structure, the separated electrodes are electrically connected to each other through, for example, a member called a jumper. In addition, a transparent electrode is used in the electrode jumper. For example, in the case where the jumper connects the separated Y electrodes to each other, in order to ensure insulation from the X electrode, an insulating layer is provided at the bottom of the jumper. In addition, usually, an insulating film (protective film) is formed on each electrode configured in a single-sided manner.

[0290] Therefore, when the touch panel of this embodiment has a single-sided touch panel structure, the touch panel of this embodiment can use the cured film of this embodiment for example as an insulating film formed on an electrode, an insulating layer formed under a bridge portion, or both.

[0291] In addition, when the touch panel is mounted on the liquid crystal display device, it can be divided into an external structure, an embedded structure, and an embedded structure according to its installation location. In the external structure and the embedded structure, the touch panel is installed in the liquid crystal panel, and in the external structure, the touch panel is installed on the outside of the liquid crystal panel. In the external structure, the touch panel is arranged between the polarizing plate on the viewing direction side and the liquid crystal laminate (a laminate composed of a pair of substrates and a liquid crystal layer between them). In addition, in the embedded structure, the liquid crystal layer of the liquid crystal laminate has a touch panel function. The touch panel of this embodiment can be applied to any structure, but is preferably used in an external structure, for example.

[0292] Hereinafter, one form of the touch panel according to the present embodiment will be described using drawings. Figure 1 FIG. 1 is a top view showing a structure of a touch panel according to the present embodiment. Figure 1 As shown, when the touch panel of the present embodiment is a single-sided touch panel, electrodes ( X1 to X4 , Y1 to Y3 ) made of a conductive material are formed on a substrate 10 .

[0293] The raw material of the substrate 10 is not particularly limited, and a flexible substrate having flexibility can be used in addition to a hard substrate. As the raw material of the substrate 10, for example, a glass plate such as soda-lime glass, low-alkali borosilicate glass, and alkali-free aluminoborosilicate glass, a plastic plate or a plastic film formed of polyethylene terephthalate (PET), triacetyl cellulose (TAC), polymethyl methacrylate (PMMA), polycarbonate (PC), etc. can be used.

[0294] The electrodes (X1 to X4, Y1 to Y3) are transparent electrodes. The material of the transparent electrodes is not particularly limited as long as at least a part of the transparent electrodes contains a metal, and a known conductive material can be used.

[0295] The metal is not particularly limited, but copper, silver, gold, or alloys containing these metals are preferred, especially for flexible applications. In addition, organic conductive materials such as PEDOT / PSS (polyethylene dioxythiophene / polystyrene sulfonic acid), polyaniline, polypyrrole, conductive organic materials such as conductive polymer particles, superconductor particles, and organometallic compounds may also be used. These materials may be used alone or in combination of two or more.

[0296] It should be noted that although Figure 1 and 2 Although the description is omitted in the figure, a metal thin film having a function as a metal wiring can be used as a lower layer or in place of the transparent electrode in each electrode and the jumper 12. Metal materials such as Mo (molybdenum), Al (aluminum), and Pd (palladium) can be used in the metal thin film.

[0297] like Figure 1 As shown, electrodes X1 to X4 are along Figure 1 Electrodes arranged in the direction of arrow X in FIG. Electrodes X1 to X4 are continuously connected to electrodes adjacent to the X direction via connecting portions formed of conductive materials and are electrically connected in the X direction. It should be noted that, usually, electrodes X1 to 4 and each connecting portion are continuously formed as one when the electrode is formed.

[0298] In addition, electrodes Y1 to Y3 are arranged along Figure 1 The electrodes Y1 to Y3 are arranged in the direction of the arrow Y in FIG. 1 , and the electrodes Y1 to Y3 are separated from the adjacent electrodes, but are electrically connected to the adjacent electrodes in the Y direction via the bridge portion 12. The bridge portion 12 can be formed of the same material as the transparent electrode. In addition, an insulating film 14 is interposed between the lower portion of the bridge portion 12 in the thickness direction and the connection portion with the electrode X.

[0299] Hereinafter, the electrode group electrically connected in the X direction is referred to as "X electrode", and the electrode group electrically connected in the Y direction is referred to as "Y electrode". Figure 1 As shown, in a single-sided touch panel, X electrodes are arranged along the Y direction, and Y electrodes are arranged along the X direction.

[0300] Next, use Figure 2 The cross-sectional structure of the touch panel in this embodiment will be described. Figure 2 for Figure 1 AA cross section in. Figure 2As shown, between the electrodes Y1 and Y2, there are an insulating film 14 and a connecting portion X34 of the electrodes X3 and X4. The electrodes Y1 and Y2 are electrically connected through the bridging portion 12 as described above. In addition, at the lower portion of the bridging portion 12 in the thickness direction, between it and the connecting portion X34, a portion of the insulating film 14 extends to ensure the insulation between the bridging portion 12 and the connecting portion X34. In addition, an insulating protective layer 16 is provided on the upper side of the electrodes Y1 and Y2 and the bridging portion 12 in the thickness direction.

[0301] As described above, the insulating cured film using the curable resin composition of this embodiment has excellent chemical resistance. Therefore, for example, when the cured film of this embodiment is used as the insulating film 14, the interface ( Figure 2 The adhesion at the transparent electrode / insulating film interface (K1, K5) in the embodiment is excellent. Similarly, when the cured film of the present embodiment is used as the insulating protective layer 16, the interface (K1, K5) between the insulating protective layer 16 and the transparent electrode Figure 2 The adhesion at the transparent electrode / protective film interface (K2) is excellent.

[0302] From such a viewpoint, when the cured film of the present embodiment is used as the insulating film 14 , the influence on the transparency of the insulating film 14 and, moreover, the transparency of the touch panel can be minimized, and the touch panel can be manufactured with good productivity.

[0303] In this embodiment, the cured film of this embodiment is used for at least one of the insulating film 14 and the insulating protective layer 16. However, although the other one may be formed using a known material conventionally used for the insulating film or the protective film, it is preferred that both the insulating film 14 and the insulating protective layer 16 are the cured film of this embodiment.

[0304] In the above-mentioned touch panel, the method for forming the cured film of the present embodiment is not particularly limited. For example, a coating film can be formed on the lower layer (for example, the substrate 10 and the electrode opposite to the insulating film 14, or the electrode opposite to the insulating protective layer 16) by a coating method such as spraying, spin coating, slit die coating, roller coating, and rod coating. At this time, the dry film thickness of the coating film is not particularly limited, but for example, in the case of the insulating protective layer 16, it is preferably 0.5 to 20 μm, and more preferably 1.0 to 10 μm. Similarly, in the case of the insulating film 14, the dry film thickness is preferably 0.2 to 10 μm, and more preferably 0.5 to 5 μm. In addition, as required, for the coating film, it can be exposed by a mask having a prescribed pattern that is set in a state of contact or non-contact with the coating film. The type of light during exposure is not particularly limited, and visible light, ultraviolet light, far infrared light, electron beam, X-ray, etc. can be cited, among which ultraviolet light is preferred. The illuminance of the light is not particularly limited, but preferably 5 to 150 mW / cm at 365 nm. 2 , particularly preferably 15 to 35 mW / cm 2 .

[0305] Then, as required, in aqueous alkaline developers such as sodium carbonate, sodium hydroxide, potassium hydroxide, etc., immersion, or utilizing a sprayer etc. to spray the developer, the uncured portion is removed to form a desired pattern. In addition, in order to promote the polymerization of the photosensitive composition and harden the film, heating (post-baking) can be implemented as required.

[0306] Furthermore, for example, in the case of forming the jumper 12, first, a patterned X electrode is formed on the substrate 10, and then a curable resin composition is applied on the substrate 10 and the surface of the X electrode, and the curable resin composition is exposed and developed using a mask that can form the insulating film 14. Thus, a patterned insulating film 14 is formed including a portion extending in the lower part of the thickness direction of the jumper 12, and then a conductive pattern is formed on the substrate by a lift-off method or the like, thereby forming a transparent electrode on the insulating film 14 and on the substrate 10 from which the curable resin composition is removed, thereby forming a Y electrode and the jumper 12. Therefore, when the curable resin composition of the present embodiment is used as a curable resin composition used for resist in the formation of the X electrode, and the formation of the insulating film 14, the interface ( Figure 2 The adhesion at the substrate / transparent electrode interface (K4) is excellent.

[0307] Example

[0308] Hereinafter, the present invention will be described in more detail using Examples and Comparative Examples. The present invention is not limited to the following Examples at all.

[0309] <Synthesis example>

[0310] <Synthesis of Copolymer>

[0311] (Weight average molecular weight)

[0312] The weight average molecular weight is measured by gel permeation chromatography (GPC). Specifically, a 0.5% by mass solution obtained by dissolving a (meth)acrylic acid-based polymer in tetrahydrofuran is used as a measurement sample. The measurement conditions are as follows.

[0313] Equipment: Made by TOSOH Co., Ltd., Product No.: HLC-8320GPC

[0314] Column: Made by TOSOH Corporation, Product No.: 2 TSKgel GMHHR-H (30) connected

[0315] Eluent: Tetrahydrofuran

[0316] Flow rate: 1.0mL / min

[0317] Temperature: 40℃

[0318] Detector: RI

[0319] Molecular weight standard: Standard polystyrene

[0320] <Synthesis example 1>

[0321] (Synthesis of Alkali-Soluble Resin A-1)

[0322] Into a glass flask equipped with a heating, cooling and stirring device, a reflux condenser, and a nitrogen inlet tube, 64.05 g of methacrylic acid, 212.46 g of dicyclopentyl methacrylate (product name: FA-513M, manufactured by SHOWA DENKO MATERIALS Co., Ltd.; Tg in the case of a homopolymer: 175° C.), 205.42 g of 3,4-epoxycyclohexylmethyl methacrylate (product name: Cyclomer M100, manufactured by Daicel Co., Ltd.), and 1445.78 g of dimethylene glycol ethyl methyl ether were charged. After the gas phase in the system was replaced with nitrogen, 72.29 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was added, and the mixture was heated to 65° C. and reacted at the temperature for 13 hours to obtain a 25% by mass solution of the target polymer (alkali-soluble resin A-1). The weight average molecular weight (Mw) of the obtained polymer was measured by GPC and found to be 5,800. The Tg determined by the FOX equation was 126.0°C.

[0323] <Synthesis example 2>

[0324] (Synthesis of polymer (Ba))

[0325] 7.30 g of n-octyl acrylate, 5.08 g of 2-phenoxyethyl acrylate, 2.56 g of acrylic acid, 0.0354 g of 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name: IRGACURE TPO, manufactured by BASF) as a polymerization initiator, and 0.0206 g of 1-dodecanethiol as a chain transfer agent were mixed to obtain a curable resin composition containing a polymerization initiator.

[0326] The obtained curable resin composition was injected into a transparent glass molding mold (2.0 mm thick silicon spacer, capable of forming a film with a length of 100 mm, a width of 100 mm, and a thickness of 2.0 mm) to which a release polyethylene terephthalate film (product name: Separator SP-PET PET-01-Bu, manufactured by Mitsui Chemicals Tohcello Co., Ltd.) was attached as a release film. Next, the irradiation dose was set to 0.58 mW / cm 2 The monomer components were bulk polymerized by irradiating ultraviolet rays for 1 hour. The weight average molecular weight (Mw) of the obtained polymer was measured by GPC and found to be 265,000. The Tg obtained by the FOX equation was -25.3°C.

[0327] <Synthesis example 3>

[0328] (Synthesis of polymer (Bb))

[0329] 5.74 g of lauryl acrylate, 6.89 g of 2-phenoxyethyl acrylate, 2.32 g of acrylic acid, 0.0320 g of 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name: IRGACURE TPO, manufactured by BASF) as a polymerization initiator, and 0.0186 g of 1-dodecanethiol as a chain transfer agent were mixed to obtain a curable resin composition containing a polymerization initiator.

[0330] The obtained curable resin composition was placed in the same molding die as in Synthesis Example 2, and the monomer components were bulk polymerized by irradiation with ultraviolet rays in the same manner as in Synthesis Example 2. The weight average molecular weight (Mw) of the obtained polymer was measured by GPC and the result was 265,000. In addition, the Tg obtained by the FOX equation was 1.8°C.

[0331] <Synthesis example 4>

[0332] (Synthesis of polymer (Bc))

[0333] 7.31 g of n-octyl acrylate, 5.08 g of 2-phenoxyethyl acrylate, 2.56 g of acrylic acid, 0.0354 g of 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name: IRGACURE TPO, manufactured by BASF) as a polymerization initiator, and 0.0103 g of 1-dodecanethiol as a chain transfer agent were mixed to obtain a curable resin composition containing a polymerization initiator.

[0334] The obtained curable resin composition was placed in the same molding die as in Synthesis Example 2, and the monomer components were bulk polymerized by irradiation with ultraviolet rays in the same manner as in Synthesis Example 2. The weight average molecular weight (Mw) of the obtained polymer was measured by GPC and the result was 585,000. In addition, the Tg obtained by the FOX equation was -25.3°C.

[0335] <Synthesis example 5>

[0336] (Synthesis of polymer (Bd))

[0337] 12.34 g of n-octyl acrylate, 2.60 g of acrylic acid, 0.0359 g of 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name: IRGACURE TPO, manufactured by BASF) as a polymerization initiator, and 0.0209 g of 1-dodecanethiol as a chain transfer agent were mixed to obtain a curable resin composition containing a polymerization initiator.

[0338] The obtained curable resin composition was placed in the same molding die as in Synthesis Example 2, and the monomer components were bulk polymerized by irradiation with ultraviolet rays in the same manner as in Synthesis Example 2. The weight average molecular weight (Mw) of the obtained polymer was measured by GPC and the result was 295,000. In addition, the Tg obtained by the FOX equation was -47.3°C.

[0339] <Synthesis example 6>

[0340] (Synthesis of Polymer (Be))

[0341] 12.88 g of lauryl acrylate, 2.08 g of acrylic acid, 0.0287 g of 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name: IRGACURE TPO, manufactured by BASF) as a polymerization initiator, and 0.0167 g of 1-dodecanethiol as a chain transfer agent were mixed to obtain a curable resin composition containing a polymerization initiator.

[0342] The obtained curable resin composition was placed in the same molding die as in Synthesis Example 2, and the monomer components were bulk polymerized by irradiation with ultraviolet rays in the same manner as in Synthesis Example 2. The weight average molecular weight (Mw) of the obtained polymer was measured by GPC and the result was 577,000. In addition, the Tg obtained by the FOX equation was -10.6°C.

[0343] [Examples and Comparative Examples]

[0344] (1) Preparation of resist for insulating film

[0345] According to the composition shown in the following table, 37.73 g of the aforementioned alkali-soluble resin solution (A-1), 4.42 g of the aforementioned polymer (Ba), 10.32 g of a monofunctional monomer: 2-dicyclopentenyloxyethyl acrylate (C-1), 1.02 g of a silane coupling agent: 3-methacryloxypropyltrimethoxysilane (D-1), 1.27 g of a photopolymerization initiator: 1-[4-(phenylthio)-2-(O-benzoyl oxime)] (product name: IRGACURE OXE-01, manufactured by BASF) (E), 0.03 g of a surface conditioner (product name: FZ-2122, manufactured by Dow Chemical Japan Co., Ltd.) (F), 0.03 g of an additive: 0.03 g of o-methoxyphenol (G), 25.38 g of cyclopentanone, and 19.71 g of propylene glycol monomethyl ether acetate were mixed under light shielding to prepare the insulating film resist of Example 1. The other examples and comparative examples in the table were prepared in the same manner. It should be noted that the raw materials described in the following table are as follows.

[0346] Bb: polymer prepared in Synthesis Example 2

[0347] Bc: polymer prepared in Synthesis Example 3

[0348] Bd: polymer prepared in Synthesis Example 4

[0349] Be: polymer prepared in Synthesis Example 5

[0350] C-2: 2-(o-phenylphenoxy)ethyl acrylate (product name: ALEN-10, manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0351] C-3: 1H,1H,5H-octafluoropentyl acrylate

[0352] D-2: 3-(N-(1H-benzo[1,2,3]triazole)carboxamide)propyltrimethoxysilane (product name: x-12-1214A, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0353] D-3: N-phenyl-3-aminopropyltrimethoxysilane (product name: KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0354] D-4: The compound shown below (synthesized according to Example 1 of WO2014 / 104195)

[0355] [Chemical formula 22]

[0356]

[0357] [Table 3]

[0358]

[0359] (2) Evaluation of elongation

[0360] Each resist of Examples and Comparative Examples was slit-coated onto a release polyethylene terephthalate film (product name: Separator SP-PET PET-01-Bu, manufactured by Mitsui Chemicals Tohcello Co., Ltd.) using an applicator so that the final film thickness after curing would be 20 μm.

[0361] Next, the solvent was removed by a vacuum drying device (VCD), and then pre-baking was performed on a hot plate at 90°C for 2 minutes. The obtained coating film was irradiated with light from an ultra-high pressure mercury lamp at 4000 mJ / cm 2 Expose the entire surface (converted to i-line, illumination is 20mW / cm 2 ) and then post-baked at 90°C for 30 minutes to produce a substrate with a film thickness of 20 μm.

[0362] The obtained cured film was peeled off from the release polyethylene terephthalate film, and the elongation was measured using a tensile strength tester RTG-1310 manufactured by A&D Co., Ltd. The measurement was performed three times for each sample, and the average value was used to determine the result according to the following criteria.

[0363] 〔Benchmark〕

[0364] A: The elongation is 100% or more.

[0365] B: Elongation is 5 to 100%.

[0366] C: Elongation is less than 5%.

[0367] The results are shown in the following table.

[0368] (3) Evaluation of insulation reliability

[0369] On a 10 cm × 10 cm square glass substrate with a copper comb electrode pattern with a spacing of 50 μm, vinyl tape was attached to both ends of the electrode as a mask, and each resist of the embodiment and the comparative example was applied by a spin coater, and then dried to form a coating with a dry film thickness of 1.2 μm. The coating was heated at 90°C for 2 minutes on a hot plate. The obtained coating was irradiated with light from an ultra-high pressure mercury lamp at 100 mJ / cm 2 Expose the entire surface (converted to i-line, illumination is 20mW / cm 2 After removing the mask, post-baking was performed at 90° C. for 30 minutes to prepare a substrate for an insulation reliability test having a film thickness of 1.2 μm.

[0370] Next, an insulation reliability test was performed on the obtained insulation reliability test substrate under the conditions of a temperature of 85° C. and a humidity of 85% Rh for 500 hours by applying DC 100 V. The insulation reliability was evaluated based on the following criteria.

[0371] 〔Benchmark〕

[0372] A: Able to maintain a resistance of 1×10 11 Ω or more.

[0373] B: Able to maintain a resistance of 1×10 10 Ω or more and less than 1×10 11 Ω.

[0374] C: Resistance value is less than 1×10 10 Ω, or, the resistance value decreases in less than 500 hours.

[0375] The results are shown in the following table.

[0376] (4) Evaluation of pattern forming properties

[0377] On a 10 cm × 10 cm square glass substrate, each resist of the embodiment and the comparative example was applied by a spin coater and dried to form a coating film with a dry film thickness of 1.2 μm. The coating film was heated at 90° C. for 2 minutes on a hot plate. The obtained coating film was irradiated with 100 mJ / cm 2 The light of the ultra-high pressure mercury lamp (converted to i line, the illumination is 20mW / cm 2). It should be noted that the exposure was performed under the condition that the interval between the mask and the substrate (exposure gap) was 100 μm. Then, alkali development was performed using a 2.38% TMAH aqueous solution. After washing with water, post-baking was performed at 90° C. for 30 minutes to produce a substrate with a pattern having a film thickness of 1.2 μm. It should be noted that by adjusting the mask opening diameter, a substrate with a pattern having a bottom diameter of 24 μm was produced.

[0378] Next, each substrate was cut out so that the shape of the obtained pattern could be observed, and the hole pattern shape was observed using a laser microscope, thereby evaluating according to the following evaluation criteria.

[0379] [Evaluation criteria for pattern formation]

[0380] A: No residue was confirmed in the through-hole.

[0381] C: A hole pattern could not be formed, or residue was observed in the through-hole.

[0382] The results are shown in the following table.

[0383] [Table 4]

[0384] Elongation Insulation Pattern formation Example 1 B B A Example 2 A B A Example 3 B B A Example 4 A B A Example 5 B B A Example 6 B A A Example 7 B A A Example 8 B A A Example 9 B A A Comparative Example 1 C B A Comparative Example 2 B B C Comparative Example 3 B B C

[0385] According to Table 5, the curable resin compositions of Examples 1 to 9 were good in elongation, insulation reliability, and pattern forming properties compared to Comparative Examples 1 to 3.

[0386] From these results, it is understood that the curable resin composition of the present embodiment is extremely excellent in elongation, insulation reliability, and pattern formability.

[0387] The entire disclosure of Japanese Patent Application No. 2022-074530 filed on April 28, 2022 is incorporated into this specification by reference.

[0388] In addition, all documents, patent applications, and technical standards described in the specification are incorporated into this specification by reference to the same extent as if each document, patent application, and technical standard was specifically and individually described.

Claims

1. A polymer comprising: Unit B1 derived from an alkyl (meth)acrylate monomer (B1) containing a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen; Unit B2 derived from a (meth)acrylate monomer (B2) having an ether bond; and Unit B3, the unit B3 is derived from a (meth)acrylate monomer (B3) represented by the following formula (1), [Chemical formula 1] In formula (1), R 1 Represents a hydrogen atom or a methyl group; R 2 is a hydrogen atom or a group selected from the groups represented by the following formula (2); [Chemical formula 2] In formula (2), X 1 represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen; R 3 is a group selected from the following formula (3) or the following formula (4); [Chemical formula 3] In formula (3), X 2 represents a linear or branched divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have an unsaturated bond and may be substituted with a halogen; [Chemical formula 4] In formula (4), ring A represents a cyclic hydrocarbon group having 3 to 10 carbon atoms which may have an unsaturated bond, in which a part of the carbon atoms constituting the ring may be replaced by oxygen or nitrogen and which may have a substituent, or an aromatic group having 4 to 10 carbon atoms which may have a substituent; R 4 is a group selected from the group consisting of a linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms and a carboxyl group; n represents an integer greater than 1, and at least one R 4 It is a carboxyl group.

2. The polymer according to claim 1, wherein The unit B1 is represented by the following formula (B1-1), [Chemical formula 5] In formula (B1-1), Z 1 represents a hydrogen atom or a methyl group, Z 2 It represents a linear or branched aliphatic hydrocarbon group having 5 to 20 carbon atoms which may have an unsaturated bond and may be substituted with a halogen.

3. The polymer according to claim 1, wherein The unit B2 is represented by the following formula (B2-1), [Chemical formula 6] In formula (B2-1), Z 1 represents a hydrogen atom or a methyl group, Q 1 represents a single bond or an ether bond, a linear, branched or cyclic divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, which may have an unsaturated bond and may be substituted with a halogen, and W 1 represents an aromatic group or a cyclic aliphatic hydrocarbon group which may contain an ether bond; wherein Q 1 and W 1 At least one of the compounds has one or more ether bonds.

4. The polymer according to claim 1, which has a weight average molecular weight of 100,000 to 400,000.

5. The polymer according to claim 1, which has a glass transition temperature (Tg) of 20°C or less.

6. A curable resin composition comprising: Alkali soluble resin (A); A polymer (B), wherein the polymer (B) is the polymer according to any one of claims 1 to 5; and Monofunctional monomer (C).

7. The curable resin composition according to claim 6, wherein The alkali-soluble resin (A) is a copolymer comprising the following units: a unit (a-1) derived from the compound represented by the formula (1); a unit (a-2) having a glass transition temperature of 70 to 200° C. when a homopolymer is prepared; and a unit (a-3) derived from an unsaturated compound containing an epoxy group.

8. The curable resin composition according to claim 6, wherein The monofunctional monomer (C) is a monofunctional (meth)acrylate monomer which may have an ether bond in its structure. 9 . The curable resin composition according to claim 6 , further comprising a silane coupling agent.

10. The curable resin composition according to claim 6, which is used for pattern formation.

11. An elongated insulating cured film obtained by curing the curable resin composition according to claim 6. 12 . An insulating cured film for a touch panel, obtained by curing the curable resin composition according to claim 6 . 13 . A touch panel comprising the insulating cured film for a touch panel according to claim 12 .

14. An insulating cured film for a flexible printed circuit board, which is obtained by curing the curable resin composition according to claim 6. 15 . A flexible printed circuit board comprising the insulating cured film for a flexible printed circuit board according to claim 14 .

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