JP2023074384A - Copolymer, resin composition, interlayer insulation film, protection film and image display device - Google Patents

Abstract

To provide a resin composition that can form a cured product having sufficiently low-temperature curability and excellent solvent resistance, and a copolymer contained in the resin composition.SOLUTION: A copolymer contains a constitutional unit having a conjugated diene moiety in a side chain, a constitutional unit having a group represented by a formula (1) (R1 and R2 each denote a C1 to 20 hydrocarbon group and R3 and R4 each denote a hydrogen atom or a C1 to 20 hydrocarbon group). The copolymer is free of a carboxy group.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a copolymer, a resin composition containing the same, an interlayer insulating film, a protective film, and an image display device containing a cured product of the resin composition.

Image display devices include organic electroluminescence (EL) display devices (in particular, WRGB system combining a white light emitting organic EL and color filters), liquid crystal display devices, integrated circuit devices, solid-state imaging devices, and the like. These image display elements are generally provided with films and fine patterns such as color filters, photospacers, projections for liquid crystal alignment, microlenses, and insulating films for touch panels. As the color filter, one having a black matrix and pixels formed of a colored pattern formed on a substrate and a protective film formed thereon is usually used.

In recent years, as displays have become more flexible and wearable, substrate materials are being switched from glass to organic materials such as resins. Organic materials are inferior to glass in heat resistance. Therefore, in a member formed by thermosetting a resin composition on a substrate, it is desired to lower the temperature for thermosetting the resin composition according to the heat resistance of the substrate made of an organic material.
For example, color filters have conventionally been formed by thermosetting a resin composition on a substrate at a temperature of 210 to 230°C. However, when a color filter is formed on a flexible substrate made of a resin, the resin composition is required to be thermally cured at a temperature of 80 to 150° C. because the substrate has poor heat resistance.

Conventionally, as a resin composition used as a material for color filters, there are those described in Patent Document 1 and Patent Document 2, for example.
Patent Document 1 discloses (a) a polymerization initiator having an absorption coefficient at 365 nm in methanol of 1.0 × 10 ³ mL/gcm or more, and (b) an absorption coefficient at 365 nm in methanol of 1.0 × 10 ² mL/gcm or less, a polymerization initiator having an absorption coefficient at 254 nm of 1.0×10 ³ mL/gcm or more, (c) a compound having an unsaturated double bond, (d) an alkali-soluble resin, ( e) A photosensitive coloring composition containing a colorant is disclosed.
Patent Document 2 discloses a photosensitive composition for a color filter containing a compound (A) containing a furyl group, a compound (B) containing a photopolymerizable functional group, a photopolymerization initiator (C), and a colorant. disclosed.

JP 2015-041058 A JP 2017-194662 A JP 2017-115162 A

Resin compositions used for members of image display elements are required to be cured at a low heating temperature.
However, when the heating temperature for curing the conventional resin composition is lowered, a cured product having sufficient solvent resistance cannot be obtained. Therefore, there is a demand for a resin composition with good low-temperature curability that can form a cured product with excellent solvent resistance even at a low heating temperature for curing.

The present invention has been made in view of the above circumstances, and provides a resin composition having excellent low-temperature curability and capable of forming a cured product having good solvent resistance, and a copolymer contained in this resin composition. intended to provide
In addition, the present invention includes an interlayer insulating film having good solvent resistance made of a cured product of a resin composition having excellent low-temperature curability, a protective film made of the cured product, and a cured resin film made of the cured product. An object of the present invention is to provide an image display device.

The present invention includes the following aspects.
[1] a structural unit (a) having a conjugated diene moiety in its side chain;
a structural unit (b) having a group represented by the following formula (1);
contains
A copolymer characterized by not containing a carboxy group.

（式（１）中、Ｒ^１およびＲ^２は、それぞれ独立に、炭素原子数１～２０の炭化水素基である。Ｒ^３およびＲ^４は、それぞれ独立に、水素原子または炭素原子数１～２０の炭化水素基である。＊は結合部位を表す。）

(In Formula (1), R ¹ and R ² are each independently a hydrocarbon group having 1 to 20 carbon atoms; R ³ and R ⁴ are each independently a hydrogen atom or a 20 hydrocarbon groups.* represents the bonding site.)

[2] the structural unit (a) having a conjugated diene moiety in the side chain is a structural unit derived from a conjugated diene-containing monomer (ma);
The copolymer according to [1], wherein the conjugated diene moiety is a furan ring.
[3] The copolymer according to [2], wherein the conjugated diene-containing monomer (ma) is a furan ring-containing (meth)acrylate.

[4] R ¹ and R ² of the structural unit (b) are each independently a hydrocarbon group having 1 to 3 carbon atoms, and R ³ and R ⁴ are each independently a hydrogen atom or methyl The copolymer according to any one of [1] to [3], which is a group.
[5] The content of the structural unit (a) is 1 to 99 mol%,
The copolymer according to any one of [1] to [4], wherein the content of the structural unit (b) is 1 to 99 mol%.

[6] further containing another structural unit (c),
The copolymer according to any one of [1] to [5], wherein the other structural unit (c) comprises an alkyl (meth)acrylate-derived structural unit.
[7] The content of the structural unit (a) is 1 to 50 mol%,
The content of the structural unit (b) is 1 to 50 mol%,
The copolymer according to [6], wherein the content of the structural unit (c) is 30 to 98 mol%.

[8] the copolymer (A) according to any one of [1] to [7];
a basic catalyst (B);
a solvent (C);
A resin composition containing

[9] The resin composition according to [8], wherein the basic catalyst (B) is a compound represented by the following formula (5).
R ¹¹ N=CR ¹² -NR ¹³ R ¹⁴ (5)
(In the formula (5), R ¹¹ is a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a group represented by —N(R ¹⁵ ) ₂ (wherein R ¹⁵ is a hydrogen atom or a carbon atom two R ¹⁵ may be the same or different, and each of R ¹² , R ¹³ and R ¹⁴ is a hydrogen atom or a carbon atom; It is a hydrocarbon group having an atom number of 1 to 20. Any two or more of R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and two R ¹⁵ groups may combine to form a cyclic structure. good.)

[10] The basic catalyst (B) is 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-nonene, and 1,1 , 3,3-tetramethylguanidine, the resin composition according to [8] or [9].
[11] a reactive diluent (D);
The resin composition according to any one of [8] to [10], further containing a photopolymerization initiator (E).

[12] With respect to a total of 100 parts by mass of the copolymer (A) and the reactive diluent (D),
Containing 10 to 90 parts by mass of the copolymer (A),
Containing 0.001 to 1 part by mass of the basic catalyst (B),
Containing 30 to 1000 parts by mass of the solvent (C),
Containing 10 to 90 parts by mass of the reactive diluent (D),
Containing 0.1 to 30 parts by mass of the photopolymerization initiator (E),
The resin composition according to [11].

[13] An interlayer insulating film comprising a cured product of the resin composition according to any one of [8] to [12].
[14] A protective film comprising a cured product of the resin composition according to any one of [8] to [12].
[15] An image display device comprising a cured resin film comprising a cured product of the resin composition according to any one of [8] to [12].

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a resin composition which has excellent low-temperature curability and can form a cured product having good solvent resistance, and a copolymer contained as a material in this resin composition. Furthermore, according to the present invention, an interlayer insulating film having good solvent resistance comprising a cured product of the resin composition having excellent low-temperature curability, a protective film having good solvent resistance comprising the cured product, and the cured product It is possible to provide an image display device having a resin cured film having good solvent resistance.

The copolymer, resin composition, interlayer insulating film, protective film and image display device of the present invention are described in detail below. In addition, this invention is not limited only to embodiment shown below.
As used herein, "(meth)acrylic acid" means at least one selected from methacrylic acid and acrylic acid. "(Meth)acrylate" means at least one selected from methacrylate and acrylate.

<Copolymer (A)>
The copolymer (A) of the present embodiment comprises a structural unit (a) having a conjugated diene site in a side chain (hereinafter also simply referred to as "structural unit (a)") and the following formula (1) and a structural unit (b) having a group (hereinafter also simply referred to as "structural unit (b)"). The copolymer (A) of the present embodiment does not contain a carboxy group (--C(=O)OH). In the copolymer (A) of the present embodiment, if necessary, other structural units (c) other than the structural unit (a) and the structural unit (b) (hereinafter, simply referred to as "structural unit (c)") ) may be contained.

（式（１）中、Ｒ^１およびＲ^２は、それぞれ独立に、炭素原子数１～２０の炭化水素基である。Ｒ^３およびＲ^４は、それぞれ独立に、水素原子または炭素原子数１～２０の炭化水素基である。＊は結合部位を表す。）

(In Formula (1), R ¹ and R ² are each independently a hydrocarbon group having 1 to 20 carbon atoms; R ³ and R ⁴ are each independently a hydrogen atom or a 20 hydrocarbon groups.* represents the bonding site.)

[Structural unit (a) having a conjugated diene moiety in the side chain]
The structural unit (a) having a conjugated diene site in the side chain contained in the copolymer (A) does not have the group represented by the above formula (1) and the carboxy group, and has a conjugated diene site and an ethylenically unsaturated and The structural unit (a) may be of only one type, or may be of two or more types. The copolymer (A) of the present embodiment contains the structural unit (a), so that the dienophile moiety derived from the group represented by the above formula (1) of the structural unit (b) and the Diels-Alder reaction can be crosslinked by

The conjugated diene moiety of the structural unit (a) having a conjugated diene moiety in the side chain includes aliphatic hydrocarbon skeletons such as 1,3-butadiene skeleton; aromatic hydrocarbon skeletons such as anthranyl ring; cyclopentadiene, dicyclo Cyclic dienes such as pentadiene and cyclohexa-2,4-dienone rings; imidazole ring, furan ring, triazine ring, thiophene ring, pyrrole ring, thiophene-1-oxide ring, thiophene-1,1-dioxide ring, cyclopenta- heterocyclic skeletons such as 2,2-dihydropyridine ring, 2H thiopyran-1,1-dioxide ring and pyran-2-one ring; Among these conjugated diene sites, a cyclic diene or heterocyclic skeleton is preferable, and a furan ring is more preferable, from the viewpoint of excellent reactivity in the Diels-Alder reaction.

The structural unit (a) is a structural unit derived from a conjugated diene-containing monomer (ma) (hereinafter also simply referred to as "monomer (ma)"). The monomer (ma) serving as the structural unit (a) in the present embodiment does not have the group represented by the above formula (1) and the carboxyl group, but has a conjugated diene moiety and an ethylenically unsaturated bond. Monomer (ma) is preferably a monomer having a vinyl group or (meth)acryloyloxy group as an ethylenically unsaturated group from the viewpoint of ease of synthesis of copolymer (A), and (meth)acryloyl A monomer having an oxy group is more preferred.

Examples of the conjugated diene-containing monomer (ma) include a compound obtained by urethanizing an isocyanate compound having an ethylenically unsaturated group and an isocyanato group and a compound having a conjugated diene moiety and an active hydrogen. A conventionally known method can be used as a method for urethanizing the isocyanate compound and the compound having a conjugated diene site and an active hydrogen.
Examples of the isocyanate compound used as a starting material for the monomer (ma) include compounds represented by the following formula (4).

（式（４）中、Ｒ^５は、水素原子又はメチル基を示す。Ｒ^６は、－ＣＯ－、－ＣＯＯＲ^７－（ここで、Ｒ^７は炭素原子数１～６のアルキレン基である。）又は－ＣＯＯ－Ｒ^８Ｏ－ＣＯＮＨ－Ｒ^９－（ここで、Ｒ^８は炭素原子数２～６のアルキレン基であり、Ｒ^９は置換基を有していてもよい炭素原子数２～１２のアルキレン基又は炭素原子数６～１２のアリーレン基である。）を示す。）

(In Formula (4), R ⁵ represents a hydrogen atom or a methyl group. R ⁶ represents —CO—, —COOR ⁷ — (wherein R ⁷ is an alkylene group having 1 to 6 carbon atoms. ) or -COO-R ⁸ O-CONH-R ⁹ - (here, R ⁸ is an alkylene group having 2 to 6 carbon atoms, and R ⁹ is an optionally substituted C 2 to 12 alkylene group or an arylene group having 6 to 12 carbon atoms.)).

In the isocyanate compound represented by formula (4), ^R5 is a hydrogen atom or a methyl group. R ⁶ in formula (4) is -C(=O)-, -C(=O)OR ⁷ - (wherein R ⁷ is an alkylene group having 1 to 6 carbon atoms) or -C (=O) O—R ⁸ O—CONH—R ⁹ — (wherein R ⁸ is an alkylene group having 2 to 6 carbon atoms, and R ⁹ is an optionally substituted C 2 to 12 alkylene groups or 6 to 12 carbon atoms arylene groups). R ⁶ is preferably -C(=O)OR ⁷ -, since a compound used as a raw material for the isocyanate compound represented by formula (4) is easily available, and R ⁷ has 1 carbon atom. It is more preferably an alkylene group of ∼4.

Specific examples of the isocyanate compound represented by the above formula (4) include 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2 -isocyanato-1-methylethyl (meth)acrylate, 2-isocyanato-1,1-dimethylethyl (meth)acrylate, 4-isocyanatocyclohexyl (meth)acrylate, methacryloyl isocyanate and the like.

Further, as the isocyanate compound used as a raw material for the monomer (ma), equimolar amounts of 2-hydroxyalkyl (meth)acrylate and diisocyanate compound (2-hydroxyalkyl (meth)acrylate: diisocyanate compound = 1 mol: 1 mol) may be used.
The alkyl group of the 2-hydroxyalkyl (meth)acrylate is preferably an ethyl group or an n-propyl group, more preferably an ethyl group, since it is a compound that readily reacts with a diisocyanate compound.

Examples of the diisocyanate compound include hexamethylene diisocyanate, 2,4- (or 2,6-) tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), 3,5,5-trimethyl-3 -isocyanatomethylcyclohexyl isocyanate (IPDI), m-(or p-)xylene diisocyanate, 1,3-(or 1,4-)bis(isocyanatomethyl)cyclohexane, lysine diisocyanate and the like.

Other isocyanate compounds used as starting materials for the monomer (ma) include 1,1-bis(methacryloyloxymethyl)methyl isocyanate, 1,1-bis(methacryloyloxymethyl)ethyl isocyanate, 1,1 -bis(acryloyloxymethyl)methyl isocyanate and 1,1-bis(acryloyloxymethyl)ethyl isocyanate.

The isocyanate compound used as a raw material for the monomer (ma) is 2-isocyanatoethyl (meth)acrylate, 2-isocyanato, from the viewpoint of low-temperature curing of the resin composition containing the copolymer (A). Propyl (meth) acrylate, 3-isocyanatopropyl (meth) acrylate, 2-isocyanato-1-methylethyl (meth) acrylate, 1,1-bis (methacryloyloxymethyl) ethyl isocyanate, 2-isocyanato-1,1- Dimethylethyl (meth)acrylate, 4-isocyanatocyclohexyl (meth)acrylate and methacryloyl isocyanate are preferred, 2-isocyanatoethyl (meth)acrylate and 2-isocyanatopropyl (meth)acrylate, 1,1-bis (Methacryloyloxymethyl)ethyl isocyanate is more preferred.

Examples of the compound having a conjugated diene moiety and an active hydrogen used as a starting material for the monomer (ma) include 2,4-hexadien-1-ol, 2-(hydroxymethyl)anthracene, 2-hydroxymethyl- 1-methylimidazole, 1-(2-hydroxyethyl)imidazole, 4(5)-(hydroxymethyl)imidazole, 1-(3-aminopropyl)imidazole, furfuryl alcohol, 2,5-furandiol, furfurylamine, 5-methylfurfurylamine and the like. These compounds may be used alone or in combination of two or more. Among these compounds, compounds containing one functional group having an active hydrogen such as 2,4-hexadien-1-ol, 1-(2-hydroxyethyl)imidazole, furfuryl alcohol, and furfurylamine undergo Diels-Alder reaction. is preferred from the viewpoint of excellent reactivity, and furfuryl alcohol is more preferred.

As the conjugated diene moiety-containing monomer (ma), it is possible to use furan ring-containing (meth)acrylates such as 2-[(2-furanylmethoxy)carbonylamino]ethyl (meth)acrylate and furfuryl (meth)acrylate. preferable. Among these furan ring-containing (meth)acrylates, the monomer (ma) is preferably 2-[(2-furanylmethoxy)carbonylamino]ethyl methacrylate because it is readily available.

The content of the structural unit (a) in the copolymer (A) can be appropriately determined depending on the use of the copolymer (A). The content of the structural unit (a) is preferably 1 to 99 mol%, more preferably 20 to 80 mol%, even more preferably 40 to 60 mol%. When the content of the structural unit (a) is 1 mol% or more, the resin composition containing the copolymer (A) and the basic catalyst (B) described later has better low-temperature curability. , it tends to be possible to form a cured product with better solvent resistance. When the resin composition is heat-cured, the dienophile moiety converted from the group represented by the formula (1) of the structural unit (b) by the action of the basic catalyst (B) and the structural unit (a) This is because the Diels-Alder reaction with the conjugated diene site of (1) facilitates securing a sufficient amount of cross-linking. When the content of the structural unit (a) is 99 mol% or less, a sufficient content of the structural unit (b) can be ensured.

[Constituent unit (b)]
The structural unit (b) contained in the copolymer (A) is a monomer (mb) having no conjugated diene moiety and no carboxy group and having a group represented by the following formula (1) (hereinafter simply referred to as "monomer (m−b)”). The structural unit (b) may be of only one type, or may be of two or more types. When the resin composition containing the copolymer (A) and the basic catalyst (B) is heat-cured, the structural unit (b) converts from a group represented by the following formula (1) to a group having a dienophile moiety. converted.
Monomer (mb) is a monomer having no conjugated diene moiety and no carboxyl group and having an ethylenically unsaturated bond and a group represented by the following formula (1).

（式（１）中、Ｒ^１およびＲ^２は、それぞれ独立に、炭素原子数１～２０の炭化水素基である。Ｒ^３およびＲ^４は、それぞれ独立に、水素原子または炭素原子数１～２０の炭化水素基である。＊は結合部位を表す。）

(In Formula (1), R ¹ and R ² are each independently a hydrocarbon group having 1 to 20 carbon atoms; R ³ and R ⁴ are each independently a hydrogen atom or a 20 hydrocarbon groups.* represents the bonding site.)

In formula (1), R ¹ and R ² are each independently a hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrocarbon group having 1 to 5 carbon atoms, and the structural unit (a) and a structural unit (b) that is converted into a dienophile site that is likely to undergo a Diels-Alder reaction, a hydrocarbon group having 1 to 3 carbon atoms is more preferable. R ¹ and R ² are preferably alkyl groups, preferably methyl groups or ethyl groups, particularly preferably ethyl groups. R ¹ and R ² may be the same or different, and are preferably the same because the monomer (mb) can be easily produced.

In formula (1), R ³ and R ⁴ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms. , The conjugated diene site of the structural unit (a) and the structural unit (b) that is converted to a dienophile site that is likely to undergo a Diels-Alder reaction, so it is more preferably a hydrogen atom or a methyl group, and it is a hydrogen atom. is particularly preferred. R ³ and R ⁴ may be the same or different, and are preferably the same for easy production of the monomer (mb).

As the monomer (mb), for example, an isocyanato group in an isocyanate compound having an ethylenically unsaturated group such as a vinyl group or a (meth)acryloyloxy group in the molecule and a hydroxy group represented by the following formula (8) A compound obtained by subjecting a hydroxy group in the compound to a urethanization reaction can be mentioned.

（式（８）中、Ｒ^１、Ｒ^２、Ｒ^３およびＲ^４は、式（１）におけるＲ^１、Ｒ^２、Ｒ^３およびＲ^４と同じである。）

(In formula (8), R ¹ , R ² , R ³ and R ⁴ are the same as R ¹ , R ² , R ³ and R ⁴ in formula (1).)

A conventionally known method can be used as a method for urethanizing the isocyanate compound having an ethylenically unsaturated group and the hydroxy group-containing compound represented by the formula (8).
The above urethanization reaction can be carried out with or without the presence of a solvent. When the above urethanization reaction is carried out using a solvent, the solvent used may be any solvent that is inert to isocyanato groups, and known solvents can be used.

The above urethanization reaction is generally preferably carried out at a temperature of -10°C or higher and 90°C or lower, more preferably at a temperature of 5°C or higher and 70°C or lower, and preferably at a temperature of 10°C or higher and 40°C or lower. More preferred.
When performing the above urethanization reaction, if necessary, a urethanization catalyst such as dibutyltin dilaurate; may be used.

As the isocyanate compound used as a starting material for the monomer (mb), the same preferred examples as the compounds listed as the isocyanate compound that can be used for the conjugated diene site-containing monomer (ma) can be used. .

Examples of the hydroxy group-containing compound represented by the formula (8) used as a starting material for the monomer (mb) include malic acid ester, tartaric acid ester and citric acid ester. is preferred.
The number of carbon atoms in the two ester moieties (the number of carbon atoms in R ¹ and R ² in —COOR ¹ and —COOR ² ) contained in the hydroxy group-containing compound represented by formula (8) is not particularly limited, but each is 1 to 5. One is preferable, and 1 to 2 is more preferable.
The hydroxy group-containing compound represented by the formula (8) is diethyl malate because it becomes the structural unit (b) that is converted to the conjugated diene site of the structural unit (a) and the dienophile site that is susceptible to Diels-Alder reaction. is particularly preferred.

Specific examples of the monomer (mb) include 2-[(diethyl malate)carbonylamino]ethyl (meth)acrylate, 2-[2-[(diethylmalate)carbonylamino]ethoxy]ethyl (meth ) It is preferably one or more selected from acrylates, and the conjugated diene site of the structural unit (a) and the structural unit (b) that is converted to a dienophile site that is likely to undergo Diels-Alder reaction. , 2-[(diethyl malate)carbonylamino]ethyl acrylate.

Since the copolymer (A) contains the structural unit (b), in the resin composition containing the copolymer (A) and the basic catalyst (B), the structural unit (b ) is converted to a group having a dienophile moiety by the action of the basic catalyst (B). A group having a dienophile site undergoes a Diels-Alder reaction with a conjugated diene site of the structural unit (a) contained in the copolymer (A) to crosslink. As a result, the resin composition containing the copolymer (A) and the basic catalyst (B) is sufficiently cured even if the heating temperature for curing is sufficiently low, and exhibits excellent solvent resistance. A cured product having

The content of the structural unit (b) in the copolymer (A) can be appropriately determined depending on the use of the copolymer (A). The content of the structural unit (b) in the copolymer (A) is preferably 1 to 99 mol%, more preferably 20 to 80 mol%, and 40 to 60 mol%. More preferred. When the content of the structural unit (b) is 1 mol% or more, the resin composition containing the copolymer (A) and the basic catalyst (B) is heat-cured to obtain the structural unit (b). A dienophile moiety can be sufficiently generated from the group represented by the formula (1). As a result, the Diels-Alder reaction between the dienophile site and the conjugated diene site of the structural unit (a) facilitates ensuring a sufficient amount of cross-linking. When the content of the structural unit (b) is 99 mol% or less, a sufficient content of the structural unit (a) can be ensured.

[Other structural units (c)]
The copolymer (A) may optionally contain a structural unit (c) other than the structural unit (a) and the structural unit (b). The number of structural units (c) may be one, or two or more. The structural unit (c) is a monomer (mc) other than the above-mentioned monomers (ma) and (mb) (hereinafter also simply referred to as "monomer (mc)"). It is a structural unit having no carboxyl group.

The monomer (mc) is not particularly limited as long as it does not have a conjugated diene moiety, a group represented by formula (1), and a carboxy group and has an ethylenically unsaturated group. Examples of the monomer (mc) include (meth)acrylic acid esters, (meth)acrylic acid amides, vinyl compounds, styrenes, unsaturated dicarboxylic acid diesters, unsaturated polybasic acid anhydrides, and the like. be done.

Specific examples of (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, sec- Butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, neopentyl (meth)acrylate, benzyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate , 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, dodecyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, ethylcyclohexyl (meth)acrylate, 1,4 - cyclohexane dimethanol mono (meth) acrylate, rosin (meth) acrylate, norbornyl (meth) acrylate, 5-methylnorbornyl (meth) acrylate, 5-ethylnorbornyl (meth) acrylate, allyl (meth) acrylate, Tetrahydrofurfuryl (meth)acrylate, 1,1,1-trifluoroethyl (meth)acrylate, perfluoroethyl (meth)acrylate, perfluoro-n-propyl (meth)acrylate, perfluoro-isopropyl (meth)acrylate, triphenylmethyl (meth)acrylate, cumyl (meth)acrylate, 3-(N,N-dimethylamino)propyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentanyl (meth)acrylate, isobornyl (meth)acrylate ) acrylate, adamantyl (meth)acrylate, naphthalene (meth)acrylate, anthracene (meth)acrylate, glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxy propyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N-tert-butylaminoethyl (meth)acrylate, tetramethylpiperidyl (meth)acrylate, hexamethylpiperidyl (meth)acrylate and the like.

Specific examples of (meth)acrylic acid amides include (meth)acrylic acid amide, (meth)acrylic acid N,N-dimethylamide, (meth)acrylic acid N,N-diethylamide, (meth)acrylic acid N, N-dipropylamide, (meth)acrylic acid N,N-di-isopropylamide, (meth)acrylic acid anthracenylamide, N-isopropyl (meth)acrylamide, (meth)acrylic morpholine, diacetone (meth) acrylamide and the like.

Specific examples of vinyl compounds include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, 5-ethylbicyclo[2.2 .1]hept-2-ene, tetracyclo[4.4.0.1 ^2,5 . 1 ^7,10 ]dodeca-3-ene, 8-methyltetracyclo[4.4.0.1 ^2,5 . 1 ^7,10 ]dodeca-3-ene, 8-ethyltetracyclo[4.4.0.1 ^2,5 . 1 ^7,10 ]dodeca-3-ene, dicyclopentadiene, tricyclo[5.2.1.0 ^2,6 ]dec-8-ene, tricyclo[5.2.1.0 ^2,6 ]dec-3 -ene, tricyclo[4.4.0.1 ^2,5 ]undec-3-ene, tricyclo[6.2.1.0 ^1,8 ]undec-9-ene, tricyclo[6.2.1.0 ^1,8 ]undec-4-ene, tetracyclo[4.4.0.1 ^2,5 . 1 ^{7, 10} . 0 ^1,6 ]dodeca-3-ene, 8-methyltetracyclo[4.4.0.1 ^2,5 . 1 ^{7, 10} . 0 ^1,6 ]dodeca-3-ene, 8-ethylidenetetracyclo[4.4.0.1 ^2,5 . 1 ^7,12 ]dodeca-3-ene, 8-ethylidenetetracyclo[4.4.0.1 ^2,5 . 1 ^{7, 10} . 0 ^1,6 ]dodeca-3-ene, pentacyclo[6.5.1.1 ^3,6 . 0 ^{2, 7} . 0 ^9,13 ]pentadeca-4-ene, pentacyclo[7.4.0.1 ^2,5 . 19 ^{, 12} . 0 ^8,13 ]pentadeca-3-ene, 5-norbornene-2,3-dicarboxylic anhydride, (meth)acrylic anilide, (meth)acryloylnitrile, acrolein, vinyl chloride, vinylidene chloride, vinyl fluoride, fluorine vinylidene chloride, vinylpyridine, vinyl acetate, vinyltoluene, norbornene and the like.

Specific examples of styrenes include styrene, α-, o-, m-, p-alkyl, nitro, cyano, and amide derivatives of styrene.
Specific examples of unsaturated dicarboxylic acid diesters include diethyl citraconate, diethyl maleate, diethyl fumarate, and diethyl itaconate.
Specific examples of unsaturated polybasic acid anhydrides include maleic anhydride, itaconic anhydride, and citraconic anhydride.
These monomers (mc) may be used alone or in combination of two or more.

Among these monomers (mc), (meth)acrylic acid esters are preferred because of ease of copolymerization reaction for producing the copolymer (A), and an alkyl group having 1 to 10 carbon atoms is Alkyl (meth)acrylates having a

When the copolymer (A) contains another structural unit (c), the content ratio of the structural unit (a), the structural unit (b), and the structural unit (c) in the copolymer (A) is It can be appropriately determined according to the use of the polymer (A). The content of the structural unit (a) in the copolymer (A) is preferably 1 to 50 mol%, more preferably 3 to 40 mol%, and more preferably 5 to 30 mol%. More preferred. The content of the structural unit (b) is preferably 1 to 50 mol%, more preferably 3 to 40 mol%, even more preferably 5 to 30 mol%. The content of the structural unit (c) is preferably 30 to 98 mol%, more preferably 40 to 94 mol%, even more preferably 50 to 90 mol%. When the content of the structural unit (c) is 30 mol % or more, the effect of including the structural unit (c) becomes remarkable. In addition, it becomes easy to suppress gelation during the copolymerization reaction for producing the copolymer (A), and the storage stability, curability, and solvent resistance of the resin composition containing the copolymer (A) are improved. Easier to balance. When the content of the structural unit (c) is 98 mol% or less, the content of the structural unit (a) and the structural unit (b) in the copolymer (A) can be sufficiently ensured. Therefore, the resin composition containing the copolymer (A) has better low-temperature curability and gives a cured product with better solvent resistance.

[Structural Unit Having Carboxy Group]
Copolymer (A) does not contain a carboxy group. The carboxy group is not only derived from a structural unit having a carboxy group (-C(=O)OH), but also can be added to the copolymer (A) by a graft reaction or the like during the production of the copolymer (A). Also included are those introduced into the polymer chain of A structural unit having a carboxy group is a structural unit derived from a carboxy group-containing monomer. Carboxy group-containing monomers include, for example, (meth)acrylic acid, itaconic acid, crotonic acid, vinylbenzoic acid, α-position haloalkyl of (meth)acrylic acid, alkoxyl, halogen, nitro, unsaturated monobasic such as cyano-substituted products. acid.

If the copolymer (A) contains a carboxy group (--C(=O)OH), it has the adverse effect of deactivating the basic catalyst (B). The carboxy group in the copolymer (A) acts with the basic catalyst (B) when the resin composition containing the copolymer (A) and the basic catalyst (B) is heat-cured. It's for. Therefore, when the copolymer (A) has a carboxy group, the reaction for converting the group represented by the formula (1) of the structural unit (b) to a group having a dienophile site is suppressed, and the dienophile site is The reaction between the group possessed and the conjugated diene site possessed by the structural unit (a) is also suppressed. As a result, compared with the case where the copolymer (A) does not have a carboxyl group, the low-temperature curability of the resin composition containing this becomes insufficient, and the resistance of the cured film obtained by heat-curing the resin composition. Solvent resistance is inferior.

The polystyrene equivalent weight average molecular weight of the copolymer (A) is not particularly limited, but is preferably 1,500 to 50,000, more preferably 3,500 to 40,000, still more preferably 5,000 to 20, 000. When the weight-average molecular weight of the copolymer (A) is 1,500 or more, the resin composition containing the copolymer (A) will give a cured product having more excellent solvent resistance. When the weight average molecular weight of the copolymer (A) is 50,000 or less, the resin composition containing the copolymer (A) can be imparted with a suitable viscosity, and the resin composition can be easily handled. easier to obtain.

<Method for producing copolymer (A)>
The copolymer (A) has a monomer (ma) corresponding to a structural unit (a) having a conjugated diene site in a side chain contained in the copolymer (A), and a group represented by formula (1). It can be produced by copolymerizing a monomer (mb) corresponding to the structural unit (b). The ratio of the structural unit (a) and the structural unit (b) contained in the copolymer (A) is the total of all monomers used as raw materials for the copolymer (A) (hereinafter sometimes referred to as "raw material monomers"). is equivalent to the ratio of monomers (ma) and (mb) in

Therefore, the proportions of the monomers (ma) and (mb) in the raw material monomers used as raw materials for the copolymer (A) are preferably (ma) 1 to 99 mol%, (mb ) 1 to 99 mol%, more preferably (ma) 20 to 80 mol%, (mb) 20 to 80 mol%, still more preferably (ma) 40 to 60 mol%, (mb) 40 to 60 mol %.

When producing a copolymer (A) containing another structural unit (c), in addition to the monomers (ma) and (mb), as raw material monomers for the copolymer (A) Furthermore, a monomer (mc) may be used. In that case, the ratio of the monomers (ma), (mb), and (mc) in the raw material monomers used as raw materials for the copolymer (A) is preferably (ma) 1 ~50 mol%, (m-b) 1-50 mol%, (m-c) 30-98 mol%, more preferably (ma) 3-40 mol%, (mb) 3- 40 mol %, (m−c) 40 to 94 mol %, more preferably (ma) 5 to 15 mol %, (mb) 5 to 15 mol %, (m−c) 50 to 90 in mol %.

The copolymerization reaction of raw material monomers (monomers (ma), (mb) and optionally used monomers (mc)) used in producing the copolymer (A) can be carried out according to the technology It can be carried out in the presence or absence of a polymerization solvent according to radical polymerization methods known in the art. Specifically, for example, a raw material monomer solution is prepared by mixing a raw material monomer, a polymerization initiator, and a polymerization solvent, and a polymerization reaction is performed at a temperature of 50 to 100° C. for 1 to 20 hours in a nitrogen gas atmosphere. can.

As the polymerization solvent used in producing the copolymer (A), one or more of those that can be used in the solvent (C) contained in the resin composition described later can be used.

Examples of polymerization initiators used in copolymerizing raw material monomers include 2,2′-azobis(2,4-dimethylvaleronitrile), azobisisobutyronitrile, azobisisovaleronitrile, peroxide benzoyl, t-butylperoxy-2-ethylhexanoate and the like. These polymerization initiators may be used alone or in combination of two or more. The amount of the polymerization initiator to be used can be 0.5 to 20 parts by mass, preferably 1.0 to 10 parts by mass, per 100 parts by mass of raw material monomers (the total amount of monomers charged).

When producing the copolymer (A), additives such as polymerization inhibitors and chain transfer agents may be used, if necessary, as long as the effects of the present invention are not impaired.

<Resin composition>
Next, the resin composition of this embodiment will be described in detail.
The resin composition of the present embodiment comprises the copolymer (A) of the present embodiment, a basic catalyst (B), a solvent (C), a reactive diluent (D), and a photopolymerization initiator (E ) and In the present embodiment, a resin composition containing a copolymer (A), a basic catalyst (B), a solvent (C), a reactive diluent (D), and a photopolymerization initiator (E) will be described as an example, the reactive diluent (D) and the photopolymerization initiator (E) are contained as necessary, and the resin composition reactive diluent (D) and / or The photoinitiator (E) may not be contained.

[Copolymer (A)]
The content of the copolymer (A) in the resin composition is 100 parts by mass in total of the copolymer (A) and the reactive diluent (D) when the resin composition contains the reactive diluent (D). The amount is preferably 10 to 90 parts by mass, more preferably 30 to 85 parts by mass, and even more preferably 60 to 80 parts by mass. When the content of the copolymer (A) is 10 parts by mass or more, the resin composition has excellent low-temperature curability and can form a cured product with good solvent resistance. When the content of the copolymer (A) is 90 parts by mass or less, a sufficient content of the reactive diluent (D) can be ensured, so that a cured product having good strength and adhesion to the substrate can be formed. become a thing.

[Basic catalyst (B)]
The basic catalyst (B) is a group represented by the formula (1) of the structural unit (b) contained in the copolymer (A), wherein the carbon atom to which R ³ is bonded and R ⁴ are bonded It is not particularly limited as long as it can form a double bond with the carbon atom.

As the basic catalyst (B), one having a pKa (acidity constant) at 25° C. of 12.5 or higher is preferably used. Basic catalysts (B) corresponding to those having a pKa of 12.5 or more at 25° C. include those having a pKa of 12.5 or more in an aqueous solution, and those that are too acidic to be measured in an aqueous solution. and having a pKa of 12.5 or more in an aqueous solution converted from the measurement results in an organic solvent.

The basic catalyst (B) is preferably a compound represented by the following formula (5).
R ¹¹ N=CR ¹² -NR ¹³ R ¹⁴ (5)
(In the formula (5), R ¹¹ is a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a group represented by —N(R ¹⁵ ) ₂ (wherein R ¹⁵ is a hydrogen atom or a carbon atom two R ¹⁵ may be the same or different, and each of R ¹² , R ¹³ and R ¹⁴ is a hydrogen atom or a carbon atom; It is a hydrocarbon group having an atom number of 1 to 20. Any two or more of R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and two R ¹⁵ groups may combine to form a cyclic structure. good.)

The basic catalyst (B) may be a compound represented by formula (5-2).
R ¹⁶ N=CR ¹⁷ -NR ¹⁸ R ¹⁹ (5-2)
(In formula (5-2), R ¹⁶ , R ¹⁷ , R ¹⁸ and R ¹⁹ are hydrocarbon groups. R ¹⁶ and R ¹⁹ combine to form a cyclic structure. R ¹⁶ and R ¹⁹ is 3 to 20. R ¹⁷ and R ¹⁸ combine to form a cyclic structure. The sum of the carbon atoms of R ¹⁷ and R ¹⁸ is 3 to 20.)

In the compound represented by formula (5-2), the sum of the number of carbon atoms of R ¹⁶ and R ¹⁹ forming a cyclic structure is 3 to 20, and since it is easily available, it is preferably 5 to 10.
In the compound represented by formula (5-2), the sum of the number of carbon atoms of R ¹⁷ and R ¹⁸ forming a cyclic structure is 3 to 20, and since it is easily available, it is preferably 5 to 10.

Specific examples of the basic catalyst (B) include 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) (pKa 12.5), 1,5-diazabicyclo[4.3.0 ]-5-nonene (pKa12.7), 1,1,3,3-tetramethylguanidine (pKa13.6) is preferably used one or more selected from, in particular, the strength of the catalytic activity , compatibility with the solvent (C), ease of availability, etc., it is preferable to use 1,8-diazabicyclo[5.4.0]-7-undecene.

The content of the basic catalyst (B) in the resin composition is relative to a total of 100 parts by mass of the copolymer (A) and the reactive diluent (D) (the resin composition contains the reactive diluent (D) is not included, relative to 100 parts by mass of the copolymer (A)), preferably 0.001 to 1 part by mass, more preferably 0.01 to 0.8 parts by mass, 0.1 to 0.5 Parts by mass are more preferred. When the content of the basic catalyst (B) is 0.001 parts by mass or more, a sufficient reaction rate for converting the structural unit (b) in the copolymer (A) into a dienophile site is easily obtained, which is preferable. . When the content of the basic catalyst (B) is 1 part by mass or less, the resin composition containing the basic catalyst (B) gels due to the excessive content of the basic catalyst (B). It is preferable because there is no decrease in workability when applying or the solvent resistance of the cured product of the resin composition is not deteriorated.

[Solvent (C)]
The solvent (C) comprises the basic catalyst (B) and the carbon atom to which R ³ in the group represented by the formula (1) of the structural unit (b) contained in the copolymer (A) is bonded, and R ⁴ are not particularly limited as long as they are inert to the reaction forming a double bond with the carbon atom to which R 4 is bonded. Specifically, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monoethyl. (poly)alkylene glycol monoalkyl ethers such as ethers and 3-methoxy-1-butanol; methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, 2-hydroxy- Hydroxy group-containing carboxylic acid esters such as ethyl 2-methylpropionate, ethyl hydroxyacetate, and methyl 2-hydroxy-3-methylbutyrate; hydroxy group-containing solvents such as diethylene glycol, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, (poly)alkylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate; ethers such as diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether and tetrahydrofuran; methyl ethyl ketone, cyclohexanone, 2-heptanone , ketones such as 3-heptanone; methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl ethoxyacetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, acetic acid ethyl, n-butyl acetate, i-propyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, ethyl pyruvate, esters such as n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxobutyrate; aromatic hydrocarbons such as toluene and xylene; N-methylpyrrolidone, N,N-dimethylformamide, N,N -Hydroxy group-free solvents such as carboxylic acid amides such as dimethylacetamide. These solvents may be used alone or in combination of two or more.

Among these solvents (C), ethers are preferably used from the viewpoint of availability, cost, solubility and dispersibility of raw materials in preparing the resin composition, and storage stability of the resin composition. is preferred, and specifically, one or more selected from propylene glycol monomethyl ether acetate, diethylene glycol methyl ethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, and 3-methoxy-1-butanol is more preferably used. preferable.

The content of the solvent (C) in the resin composition is preferably 30 to 1,000 parts by mass with respect to a total of 100 parts by mass of the copolymer (A) and the reactive diluent (D). More preferably 50 to 800 parts by mass. When the content of the solvent (C) is 30 parts by mass or more, the resin composition can have an appropriate viscosity according to the application. When the content of the solvent (C) is 1,000 parts by mass or less, the solvent (C ) can be removed.

[Reactive diluent (D)]
The reactive diluent (D) is a monomer composed of a compound having at least one ethylenically unsaturated bond as a polymerizable functional group in its molecule. A reactive diluent (D) is optionally included. The reactive diluent (D) may be a monofunctional monomer or a polyfunctional monomer having multiple polymerizable functional groups. By containing the reactive diluent (D), the resin composition of the present embodiment can have an appropriate viscosity according to the application. In addition, since the resin composition of the present embodiment contains the reactive diluent (D), it has good photocurability and can form a cured product with good strength and adhesion to the substrate. .

Monofunctional monomers used as reactive diluents (D) include (meth)acrylamide, methylol (meth)acrylamide, methoxymethyl (meth)acrylamide, ethoxymethyl (meth)acrylamide, propoxymethyl (meth)acrylamide, butoxymethoxy Methyl (meth)acrylamide, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth) Acrylate, 4-hydroxybutyl (meth)acrylate, 2-phenoxy-2-hydroxypropyl (meth)acrylate, 2-(meth)acryloyloxy-2-hydroxypropyl phthalate, glycerin mono (meth)acrylate, tetrahydrofurfuryl (meth)acrylate ) acrylate, glycidyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, phthalic acid derivative half (meth) acrylate, etc. (meth)acrylates; aromatic vinyl compounds such as styrene, α-methylstyrene, α-chloromethylstyrene and vinyltoluene; carboxylic acid esters such as vinyl acetate and vinyl propionate; These monofunctional monomers may be used alone or in combination of two or more.

Polyfunctional monomers used as reactive diluents (D) include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, and polypropylene glycol. Di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexane glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerin di(meth)acrylate acrylates, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 2,2-bis(4-(meth)acryloxydi ethoxyphenyl)propane, 2,2-bis(4-(meth)acryloxypolyethoxyphenyl)propane, 2-hydroxy-3-(meth)acryloyloxypropyl (meth)acrylate, ethylene glycol diglycidyl ether di(meth) acrylates, diethylene glycol diglycidyl ether di(meth)acrylate, phthalic acid diglycidyl ester di(meth)acrylate, glycerin triacrylate, glycerin polyglycidyl ether poly(meth)acrylate, urethane (meth)acrylate (i.e. tolylene diisocyanate), Reaction products of trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, etc., and 2-hydroxyethyl (meth)acrylate, (meth)acrylates such as tris(hydroxyethyl)isocyanurate tri(meth)acrylate; divinylbenzene, diallyl phthalate, diallyl Aromatic vinyl compounds such as benzene phosphonate; Dicarboxylic acid esters such as divinyl adipate; and condensates of. These polyfunctional monomers may be used alone or in combination of two or more.

Among these monomers, it is preferable to use a polyfunctional (meth)acrylate as the reactive diluent (D) because it results in a resin composition with good photocurability. Specifically, trimethylolpropane tri(meth) ) acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like.

The content of the reactive diluent (D) in the resin composition is preferably 10 to 90 parts by mass with respect to a total of 100 parts by mass of the copolymer (A) and the reactive diluent (D). , more preferably 15 to 70 parts by mass, more preferably 20 to 40 parts by mass. When the content of the reactive diluent (D) is 10 parts by mass or more, the effect of containing the reactive diluent (D) becomes remarkable. When the content of the reactive diluent (D) is 90 parts by mass or less, the content of the copolymer (A) can be sufficiently ensured, so that the resin composition has even better low-temperature curability. Become.

[Photoinitiator (E)]
A photoinitiator (E) is contained as needed. The photopolymerization initiator (E) is not particularly limited, but for example, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl-]-,-1-(O- acetyloxime), benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin butyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 4-(1-t-butyldioxy- 1-methylethyl)acetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone acetophenones such as -1; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; xanthone, thioxanthone, 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone , thioxanthones such as 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone, 4-(1-t-butyldioxy-1-methylethyl)benzophenone, 3,3′,4,4′- benzophenones such as tetrakis(t-butyldioxycarbonyl)benzophenone; acylphosphine oxides; and the like. These photoinitiators (E) may be used alone or in combination of two or more.

The content of the photopolymerization initiator (E) in the resin composition is 0.1 to 30 parts by mass with respect to a total of 100 parts by mass of the copolymer (A) and the reactive diluent (D). is preferable, 0.5 to 15 parts by mass is more preferable, and 1 to 10 parts by mass is even more preferable. When the content of the photopolymerization initiator (E) is 0.1 parts by mass or more, the resin composition has good photocurability. When the content of the photopolymerization initiator (E) is 30 parts by mass or less, it is possible to prevent the physical properties of the cured product of the resin composition from being adversely affected by the excessive amount of the photopolymerization initiator (E).

The resin composition of the present embodiment contains 10 to 90 parts by mass of the copolymer (A) and a basic catalyst (B ) of 0.001 to 1 part by mass, a solvent (C) of 30 to 1000 parts by mass, a reactive diluent (D) of 10 to 90 parts by mass, and a photopolymerization initiator (E) of 0.1 to 30 parts by mass. It is preferable to contain.

The resin composition of the present embodiment comprises a copolymer (A), a basic catalyst (B), a solvent (C), a reactive diluent (D), and a photopolymerization initiator (E) in addition to If necessary, one or more known additives such as colorants, coupling agents, leveling agents and thermal polymerization inhibitors may be contained. The blending amount of these additives is not particularly limited as long as it does not impair the effects of the present invention.
The additive contained in the resin composition may be one added during preparation of the resin composition, or may be one added during production of the copolymer (A), It may be a residue of those used in synthesizing the raw material monomers used in producing the copolymer (A).

<Method for producing resin composition>
The resin composition of this embodiment can be produced by a method of mixing the copolymer (A), the basic catalyst (B) and the solvent (C) using a known mixing device. At this time, the copolymer (A), the basic catalyst (B), the solvent (C), and optionally the reactive diluent (D), the photopolymerization initiator (E), and the above additives You may mix any 1 type(s) or 2 or more types chosen from.
Further, the resin composition of the present embodiment is obtained by mixing the copolymer (A) and the solvent (C) to form a mixture, and then adding a basic catalyst (B) to the mixture, and optionally The reactive diluent (D), the photopolymerization initiator (E), and any one or more selected from the above additives may be added and mixed.

When producing the resin composition of the present embodiment, the reaction liquid obtained by the copolymerization reaction of the raw material monomers for producing the copolymer (A) may be used as it is as the raw material. In this case, the resin composition of the present embodiment contains additives such as the polymerization initiator used in producing the copolymer (A), the solvent used as necessary, and the polymerization inhibitor. good too. Further, the copolymer (A) is isolated from the reaction liquid obtained by copolymerizing the raw material monomers to produce the copolymer (A) as a raw material for producing the resin composition. may be used.

When producing the resin composition of the present embodiment, the copolymer (A) and/or the basic catalyst (B) used as raw materials may be in the form of a mixture with a solvent. In this case, the solvent contained in the mixture with the copolymer (A) and/or the basic catalyst (B) can be used as the solvent (C) contained in the resin composition.

Since the resin composition of the present embodiment contains the copolymer (A) of the present embodiment and the basic catalyst (B), the structural unit ( The group represented by formula (1) in b) is converted to a group having a dienophile moiety by the action of the basic catalyst (B). A group having a dienophile site undergoes a Diels-Alder reaction with a conjugated diene site of the structural unit (a) contained in the copolymer (A) to crosslink. Therefore, the resin composition of the present embodiment has good low-temperature curability and can form a cured product with excellent solvent resistance.

In the present embodiment, the conversion reaction in which the group represented by the formula (1) of the structural unit (b) is converted into a dienophile moiety proceeds by heating the resin composition to, for example, 50 to 120°C. Therefore, the temperature at which the resin composition of the present embodiment is heat-cured can be within the temperature range at which the conversion reaction proceeds. The temperature at which the resin composition is heat-cured is preferably 70 to 100° C. in order to promote the conversion reaction.

(reaction path)
In the resin composition of the present embodiment, the group represented by the formula (1) possessed by the structural unit (b) contained in the copolymer (A) is heated in the presence of the basic catalyst (B), It is presumed that it converts to a dienophile moiety through the reaction pathway shown below.
First, in the group represented by the formula (1) of the structural unit (b), the -NH- moiety in the urethane bond and the ester moiety (-COOR ¹ or -COOR ² ) are dealcoholized.

As a result, a group having a heterocyclic ring represented by the following formula (2-1) and/or the following formula (3-1) is formed. The group having a heterocyclic ring represented by formula (2-1) is formed by dealcoholization (--R ² OH) reaction of the ester moiety containing R ² in the group represented by formula (1). . The group having a heterocyclic ring represented by formula (3-1) is formed by dealcoholization (—R ¹ OH) of the ester moiety containing R ¹ in the group represented by formula (1). .

（式（２－１）中、Ｒ^１、Ｒ^３およびＲ^４は、式（１）中のＲ^１、Ｒ^３およびＲ^４と同じである。＊は結合部位を表す。）

(In formula (2-1), R ¹ , R ³ and R ⁴ are the same as R ¹ , R ³ and R ⁴ in formula (1). * represents a binding site.)

（式（３－１）中、Ｒ^２、Ｒ^３およびＲ^４は、式（１）中のＲ^２、Ｒ^３およびＲ^４と同じである。＊は結合部位を表す。）

(In formula (3-1), R ² , R ³ and R ⁴ are the same as R ² , R ³ and R ⁴ in formula (1). * represents a binding site.)

Next, decarboxylation (—CO ₂ ) occurs at the heterocyclic moiety in the group having the heterocyclic ring represented by the above formula (2-1). As a result, the heterocyclic ring-containing group represented by formula (2-1) is converted to a group (dienophile moiety) represented by formula (2-2) below.

（式（２－２）中、Ｒ^１は、炭素原子数１～２０の炭化水素基である。Ｒ^３およびＲ^４は、それぞれ独立に、水素原子または炭素原子数１～２０の炭化水素基である。＊は結合部位を表す。）

(In formula (2-2), R ¹ is a hydrocarbon group having 1 to 20 carbon atoms; R ³ and R ⁴ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms; * represents the binding site.)

In addition, decarboxylation (—CO ₂ ) occurs at the heterocyclic portion of the group having the heterocyclic ring represented by the formula (3-1). As a result, the heterocyclic ring-containing group represented by formula (3-1) is converted to a group (dienophile moiety) represented by formula (3-2) below.

（式（３－２）中、Ｒ^２は、炭素原子数１～２０の炭化水素基である。Ｒ^３およびＲ^４は、それぞれ独立に、水素原子または炭素原子数１～２０の炭化水素基である。＊は結合部位を表す。）

(In formula (3-2), R ² is a hydrocarbon group having 1 to 20 carbon atoms. R ³ and R ⁴ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. * represents the binding site.)

For the conversion reaction of converting the group represented by the formula (1) of the structural unit (b) described above to a dienophile moiety consisting of the group represented by the formula (2-2) or (3-2), each product was performed in the density functional theory using wB97XD as the functional and 6-31+g(d) as the basis function. As a result, the reaction pathways of formulas (1), (3-1), and (3-2) are better for the conversion of formulas (1), (2-1), and (2-2). It is presumed to be the main conversion route because the activation barrier is lower than that of the root. Therefore, when the resin composition is heat-cured, a structural unit having a group represented by formula (3-2) and a structural unit having a group represented by formula (2-2) are added to the copolymer. are mixed, and the structural units having the group represented by formula (3-2) are presumed to exist more than the structural units having the group represented by formula (2-2).

Then, the dienophile moiety consisting of the group represented by the formula (2-2) or (3-2) converted from the formula (1) possessed by the structural unit (b) by the above reaction pathway is converted into the structural unit (a). Diels-Alder reaction with the conjugated diene site. Thereby, the structural unit (a) and the structural unit (b) contained in the copolymer (A) are crosslinked, and the resin composition is cured.

For this reason, when forming a cured product using the resin composition of the present embodiment, the heating temperature for curing can be lowered as compared with the case of using a conventional resin composition. Therefore, in the resin composition of the present embodiment, for example, when a coating film formed on a substrate is exposed to light and then baked, the crosslinking reaction proceeds sufficiently even if the temperature of the baking treatment is lowered. A cured product having excellent solvent resistance can be obtained.

Therefore, when the resin composition of the present embodiment is used to form a cured product, less energy is required for heating for curing. In addition, by using the resin composition of the present embodiment, a cured product can be formed on a base material having poor heat resistance such as a resin substrate without affecting the base material.

The resin composition of the present embodiment is, for example, a pixel of a color filter, a black matrix, a protective film for a color filter, an interlayer insulating film, a photospacer, a projection for liquid crystal alignment, a microlens, an image display element such as an insulating film for a touch panel. It is extremely useful as a material for forming members of

<Interlayer insulating film>
Next, the interlayer insulating film of this embodiment will be described in detail.
The interlayer insulating film of this embodiment is made of a cured product of the resin composition of this embodiment.
The interlayer insulating film of the present embodiment contains 10 to 90 parts by mass of the copolymer (A) and a basic catalyst (B ) of 0.001 to 1 part by mass, a solvent (C) of 30 to 1000 parts by mass, a reactive diluent (D) of 10 to 90 parts by mass, and a photopolymerization initiator (E) of 0.1 to 30 parts by mass. It is preferably composed of a cured product of the contained resin composition.

The interlayer insulating film of the present embodiment can be formed, for example, by applying the resin composition of the present embodiment onto a base material to form a coating film, exposing the coating film to photocuring, and then performing a baking treatment. can be manufactured.
A known method can be used as a method of applying the resin composition and a method of exposing the coating film in manufacturing the interlayer insulating film of the present embodiment.

In the present embodiment, the case where the interlayer insulating film is a cured product of the resin composition containing the photopolymerization initiator (E) has been described as an example. In the case of a cured product of a resin composition that does not have a high molecular weight, it can be produced by, for example, coating the resin composition on a substrate to form a coating film, and subjecting it to baking treatment without photocuring.

The conditions of the baking treatment performed when manufacturing the interlayer insulating film of this embodiment can be appropriately determined according to the composition of the resin composition, the film thickness of the coating film, the material of the substrate, and the like. Baking can be performed at a temperature of, for example, 70.degree. C. to 250.degree. When the temperature of the baking treatment is 70° C. or higher, a conversion reaction in which the group represented by the formula (1) of the structural unit (b) contained in the copolymer (A) in the resin composition is converted into a dienophile moiety. is promoted. Therefore, the cross-linking reaction by the Diels-Alder reaction between the dienophile site and the conjugated diene site of the structural unit (a) is promoted. As a result, good curability is obtained, and a cured product having excellent solvent resistance is obtained. The temperature of the baking treatment is preferably 75° C. or higher, more preferably 80° C. or higher. If the temperature of the baking treatment is 250° C. or less, the correlation insulating film can be formed on the substrate even if the substrate is made of a material with low heat resistance, which is preferable. The resin composition of this embodiment has good low-temperature curability. Therefore, the temperature of the baking process can be set to 160° C. or lower depending on the heat resistance of the base material on which the interlayer insulating film is formed. It may be 120° C. or lower, or 100° C. or lower.

The baking treatment performed when manufacturing the interlayer insulating film of the present embodiment can be performed, for example, for 10 minutes to 4 hours, preferably 20 minutes to 2 hours. It can be appropriately determined according to the film thickness of the coating film and the like.

The interlayer insulating film of this embodiment is made of a cured product of the resin composition of this embodiment. Therefore, the interlayer insulating film of this embodiment can be manufactured using a method of baking treatment at a low temperature, and is excellent in solvent resistance.

<Protective film>
Next, the protective film of this embodiment will be described in detail.
The protective film of this embodiment is made of a cured product of the resin composition of this embodiment.

The protective film of this embodiment can be applied as a protective film for color filters. The structure of the color filter includes, for example, a substrate, RGB pixels formed thereon, a black matrix formed at the boundary between each pixel, and a protective film formed over the pixels and the black matrix. may contain.
Pixels and black matrices, which are constituent members of the color filter, are colored patterns made of, for example, a cured product of an alkali-developable photocurable resin composition. The protective film of this embodiment is a transparent film made of a cured product of the above resin composition. In the color filter of the present embodiment, a known configuration can be adopted except for the material of the protective film.

Substrates used for color filters are not particularly limited, and include glass substrates, silicon substrates, polycarbonate substrates, polyester substrates, polyamide substrates, polyamideimide substrates, polyimide substrates, aluminum substrates, printed wiring substrates, array substrates, and the like. can be used as appropriate depending on the application.

Similar to the interlayer insulating film of the present embodiment, the protective film provided in the color filter of the present embodiment is composed of a copolymer (A) and a reactive diluent (D) of 10 to 90 parts by mass of the polymer (A), 0.001 to 1 part by mass of the basic catalyst (B), 30 to 1000 parts by mass of the solvent (C), and 10 to 90 parts by mass of the reactive diluent (D) and 0.1 to 30 parts by mass of the photopolymerization initiator (E).

<Method for producing protective film>
As a method for producing the protective film, for example, the above-described resin composition is used on a colored pattern that becomes each pixel of RGB formed on the substrate and a colored pattern that becomes a black matrix formed on the boundary of each pixel. A method of forming a transparent film can be used in the same manner as the method of manufacturing the interlayer insulating film described above.

The protective film of this embodiment is a transparent film made of a cured product of the resin composition described above. Therefore, the protective film of this embodiment can be formed by a method of performing baking treatment at a low temperature. Therefore, the energy required for baking can be reduced.

In addition, the protective film of the present embodiment can be formed on a substrate having poor heat resistance such as a resin substrate without disturbing the substrate. Therefore, it is possible to increase the selection of usable base materials. Specifically, for example, since a protective film can be formed on a base material having poor heat resistance such as a resin substrate, it is possible to contribute to flexibility of an image display element such as a display provided with a protective film. In addition, the protective film for a color filter of the present embodiment has excellent solvent resistance, and thus is less likely to cause color change of the color filter, which is preferable.

In the present embodiment, a case of producing a protective film using a resin composition containing a photopolymerization initiator (E) and using a method of photocuring the resin composition was described as an example. , Instead of the photopolymerization initiator (E) contained in the resin composition of the present embodiment, use a resin composition containing a curing accelerator and a known epoxy resin, and apply it on the substrate by an inkjet method, A protective film comprising a cured product of a resin composition containing the copolymer (A) may be formed using a heating method.

<Image display device>
The image display device of the present embodiment includes a cured resin film having good solvent resistance, which is made of a cured product of the resin composition of the present embodiment. Examples of the cured resin film include the above-described interlayer insulating film and protective film. The image display device of the present embodiment can employ a known structure other than the cured resin film made of the cured resin composition of the present embodiment. Examples of the image display device of this embodiment include a liquid crystal display device, an organic EL display device, a solid-state imaging device such as a CCD device and a CMOS device, and the like.

In the image display device of the present embodiment, the components other than the cured resin film made of the cured resin composition of the present embodiment can be manufactured by known methods. For example, when manufacturing a liquid crystal display element as an image display element, it can manufacture using the method shown below. First, a color filter is formed on a substrate. After that, electrodes, spacers, and the like are sequentially formed on the substrate having the color filters. Next, electrodes and the like are formed on another substrate, which is arranged opposite to the substrate having the color filter and is attached to the substrate. After that, a predetermined amount of liquid crystal is injected between the opposing substrates and sealed. Through the steps described above, the liquid crystal display element, which is the image display element of the present embodiment, is obtained.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples and comparative examples. It should be noted that the following examples are intended to facilitate understanding of the content of the present invention. The invention is not limited to only these examples.

[Example 1]
(Synthesis of copolymer (A))
A flask equipped with a stirring device, a dropping funnel, a condenser, a thermometer and a gas inlet tube is charged with 112 g of propylene glycol monomethyl ether acetate (manufactured by Dow Chemical Co.) as a solvent (C), and stirred while being replaced with nitrogen gas, The temperature was raised to 90°C.

Next, 15.2 g (9 mol%) of 2-[(2-furanylmethoxy)carbonylamino]ethyl methacrylate (manufactured by Showa Denko K.K., MOI-FF) as the monomer (ma) and the monomer (m 20.0 g (9 mol %) of 2-[(diethyl malate) carbonylamino] ethyl acrylate (AOI-MDE manufactured by Showa Denko KK) as -b) and 30.1 g (mc) as monomer (mc) 45 mol %) of methyl methacrylate (MMA) (manufactured by Mitsubishi Chemical Corporation), 34.7 g (37 mol %) of butyl acrylate (BuA) (manufactured by Nippon Shokubai Co., Ltd.), and 12.5 mol % as a polymerization initiator. 0 g of dimethyl 2,2′-azobis(2-methylpropionate) was mixed to prepare a mixed solution.

Using a dropping funnel, the entire amount of the prepared mixed solution was added dropwise over 2 hours into the solvent (C) in the flask under normal pressure in a nitrogen gas atmosphere. After completion of dropping, the solution in the flask was stirred and polymerized at 90° C. for 3 hours to produce a copolymer (A). Propylene glycol monomethyl ether acetate was added as a solvent (C) to the reaction solution containing the copolymer (A) thus obtained so that the components other than the solvent were 45% by mass. A polymer (A) solution was obtained.

[Examples 2 to 7, Comparative Examples 1 to 8]
Copolymer (A) solutions of Examples 2 to 7 and comparative Copolymer (A') solutions of Examples 1-8 were obtained.

Raw material monomer (conjugated diene-containing monomer (ma), formula (1 ), other monomers (mc), and methacrylic acid) are shown in Table 1 or Table 2, respectively.

As the monomers shown in Tables 1 and 2, the following were used.
"Conjugated diene-containing monomer (ma)"
・ 2-[(2-furanylmethoxy)carbonylamino]ethyl methacrylate (manufactured by Showa Denko K.K., MOI-FF)
· 2-[(2-furanylmethoxy)carbonylamino]ethyl acrylate (manufactured by Showa Denko K.K., AOI-FF)
・ Furfuryl methacrylate (FMA) (manufactured by Tokyo Kasei Co., Ltd.)

"Monomer (mb) having a group represented by formula (1)"
・ 2-[(diethyl malate) carbonylamino] ethyl acrylate (manufactured by Showa Denko K.K., AOI-MDE)
・ 2-[(Diethyl malate) carbonylamino] ethyl methacrylate (manufactured by Showa Denko K.K., MOI-MDE)
· 2-[2-[(diethyl malate)carbonylamino]ethoxy]ethyl methacrylate (manufactured by Showa Denko K.K., MOI-EG-MDE)

"Other monomers (mc)"
・Methyl methacrylate (MMA) (manufactured by Mitsubishi Chemical Corporation)
・Butyl acrylate (BuA) (manufactured by Nippon Shokubai Co., Ltd.)
· 2-[(2-tetrahydrofuranylmethoxy)carbonylamino]ethyl methacrylate (manufactured by Showa Denko K.K., MOI-THFF)
· 2-[(diethyl lactate) carbonylamino] ethyl acrylate (manufactured by Showa Denko KK, AOI-EL)
・Methacrylic acid (MAA) (manufactured by Kuraray Co., Ltd.)

Weight-average molecular weight of the copolymer (A) in the copolymer (A) solution of Examples 1 to 7 and the copolymer (A') in the copolymer (A') solution of Comparative Examples 1 to 8 (Mw) and solid content acid value (mgKOH/g) are shown in Table 3 or Table 4.
The weight average molecular weights (Mw) of the copolymers (A) of Examples 1-7 and the copolymers (A') of Comparative Examples 1-8 were calculated by the following method.

[Weight average molecular weight (Mw)]
The weight average molecular weight was measured using gel permeation chromatography (GPC) under the following conditions and calculated in terms of polystyrene.
For the GPC measurement, a GPC system manufactured by Shimadzu Corporation was used as a GPC measurement apparatus, and a differential refractive index detector RID-10A was used as a detector. As columns, three Shodex (registered trademark) LF804 and one KF-801 manufactured by Showa Denko KK were used. GPC measurement was performed under the conditions of a column temperature of 40° C. and a flow rate of 1.5 mL/min.

[Examples 11 to 18, Comparative Examples 11 to 14, 16 to 18]
A basic catalyst was added to the copolymer (A) solution of Examples 1 to 5 or the copolymer (A') solution of Comparative Examples 1 to 4, 6 to 8 in a flask under normal pressure in a nitrogen gas atmosphere. 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) (manufactured by San-Apro Co., Ltd.) as (B) was mixed in the ratio shown in Table 5 or Table 6, respectively, and Examples 11 to 18 , Comparative Examples 11 to 14 and 16 to 18 were prepared.

[Comparative Example 15]
1,6-bismaleimide-(2,2,4-trimethyl)hexane (BMI- TMH) (manufactured by Daiwa Kasei Kogyo Co., Ltd.) was mixed at the ratio shown in Table 5 to prepare a resin composition of Comparative Example 15.

Examples 11 to 18, copolymer (A) or copolymer (A') used in the production of resin compositions of Comparative Examples 11 to 18, basic catalyst (B), solvent (C), cross-linking agent , and the amounts used are shown in Table 5 or Table 6, respectively.

The blending amount of the copolymer (A) or copolymer (A') shown in Table 5 or Table 6 includes the copolymer (A) solutions of Examples 1 to 7 and the copolymers of Comparative Examples 1 to 8. (A') The amount of solvent contained in the solution is not included. In addition, the blending amount of the solvent (C) shown in Tables 5 and 6 includes the copolymer (A) solutions of Examples 1 to 7 and the copolymer (A') solutions of Comparative Examples 1 to 8. The amount of solvent is stated. No solvent was added during the preparation of the resin compositions of Examples 11-18 and Comparative Examples 11-18.
The content of each component of copolymer (A) or copolymer (A'), basic catalyst (B), solvent (C), and cross-linking agent shown in Table 5 or Table 6 is parts by mass.

[Solvent resistance evaluation 1]
Each of the resin compositions of Examples 11 to 18 and Comparative Examples 11 to 18 was placed on a glass substrate (non-alkali glass substrate) of 5 cm long and 2 cm wide using a bar coder (#34) so that the film thickness was 78 μm. to form a coating film. Then, the coating film was heated at a heating temperature of 80° C. or 100° C. for 30 minutes to volatilize the solvent (C) in the coating film, and a baking treatment was performed to obtain a cured film.

The mass of each cured film obtained was measured. Next, the glass substrates on which the cured films were formed were immersed in 100 g of acetone at 25° C. for 24 hours. After that, the glass substrate was taken out from the acetone and dried at 110° C. for 1 hour. The mass of each cured film remaining on the dried glass substrate was measured, and the residual film ratio was obtained from the following formula to evaluate the solvent resistance of the cured film. That is, the closer the residual film ratio is to 100%, the better the solvent resistance of the cured film. For evaluation, a pass line was defined as a residual film rate of 50% or more. The results are shown in Table 5 or Table 6.
Remaining film rate = (mass of cured film after immersion in acetone/mass of cured film before immersion in acetone) x 100 (%)

As shown in Table 5, the cured films of the resin compositions of Examples 11 to 18 using the copolymers (A) of Examples 1 to 7 were 100°C even when the heating temperature was 80°C. Also, the residual film rate (%) after immersion in acetone was 50% or more. From this, it was confirmed that the resin compositions of Examples 11 to 18 could give cured films exhibiting good solvent resistance even when cured at a low temperature.

On the other hand, as shown in Table 6, the cured films of the resin compositions of Comparative Examples 11 to 14 and 16 to 18 using the copolymers (A′) of Comparative Examples 1 to 4 and 6 to 8 were cured by heating. Whether the temperature was 80° C. or 100° C., the residual film rate (%) after immersion in acetone was 0%, indicating insufficient solvent resistance. From this, it was found that the resin compositions of Comparative Examples 11 to 14 and 16 to 18 did not give cured films exhibiting good solvent resistance.

This is because in the resin compositions of Comparative Examples 12 and 14, the copolymers (A') of Comparative Examples 2 and 4 do not contain the structural unit (b) having the group represented by formula (1), so the formula It is presumed that the dienophile site was not formed from the group represented by (1). Further, in the resin compositions of Comparative Examples 16 to 18, the copolymers (A') of Comparative Examples 6 to 8 contain the structural unit (b), but contain a structural unit having a carboxy group derived from methacrylic acid. Therefore, it is presumed that the basic catalyst (B) was deactivated. As a result, it is presumed that the amount of dienophile sites produced from the group represented by formula (1) became insufficient. For these reasons, in the resin compositions of Comparative Examples 12, 14, and 16 to 18, the amount of cross-linking by the Diels-Alder reaction between the dienophile site and the conjugated diene site generated from the group represented by formula (1) could not be ensured. It is presumed that this resulted in poor solvent resistance of the cured film.

Further, in the resin compositions of Comparative Examples 11 and 13, the copolymers (A') of Comparative Examples 1 and 3 do not contain the structural unit (a) having a conjugated diene moiety in the side chain. Therefore, in the resin compositions of Comparative Examples 11 and 13, the amount of cross-linking due to the Diels-Alder reaction between the dienophile site and the conjugated diene site generated from the group represented by formula (1) could not be ensured, and the solvent resistance of the cured film could not be ensured. It is presumed that this resulted in inferior performance.

In addition, the resin composition of Comparative Example 15 had a residual film rate (%) of 1% after immersion in acetone at a heating temperature of 80°C, and a residual film ratio (%) after immersion in acetone at a heating temperature of 100°C. The film ratio (%) was 0%, and the solvent resistance was insufficient. The resin composition of Comparative Example 15 contains a cross-linking agent and is a reaction system using the Diels-Alder reaction described in Patent Document 3. BMI-TMH used as a cross-linking agent in the resin composition of Comparative Example 15 is a solid imide compound and has low solubility in solvents. Therefore, it is presumed that the cross-linking agent was not uniformly dispersed in the resin composition, and the Diels-Alder reaction did not proceed sufficiently when the resin composition was applied, dried and cured.

[Examples 21 to 25, Comparative Examples 21 to 26]
Including the copolymer (A) of Examples 1 to 5 or the copolymer (A') of Comparative Examples 1 to 4 and 7 and the solvent (C) in a normal pressure flask with a nitrogen gas atmosphere 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) (manufactured by San-Apro Co., Ltd.) as a basic catalyst (B) and propylene glycol monomethyl ether acetate as a solvent (C) were added to the solution. and dipentaerythritol pentaacrylate (manufactured by Toagosei Co., Ltd.) as a reactive diluent (D), and 1-[9-ethyl-6-(2-methylbenzoyl)- as a photopolymerization initiator (E). 9H-carbazol-3-yl-]-,-1-(O-acetyloxime) (manufactured by BASF Japan Ltd.) was mixed in the proportions shown in Table 7 or Table 8, respectively, and Examples 21 to 25 and Comparative Resin compositions of Examples 21-26 were prepared.

Copolymer (A) or copolymer (A') used in the production of resin compositions of Examples 21-25 and Comparative Examples 21-26, basic catalyst (B), solvent (C), reactive dilution Agent (D), photopolymerization initiator (E), and their usage amounts are shown in Table 7 and Table 8, respectively.

The amounts of copolymer (A) or copolymer (A') shown in Tables 7 and 8 include the copolymer (A) solutions of Examples 1-5 and the copolymers of Comparative Examples 1-4 and 7. The amount of solvent contained in the polymer (A') solution is not included. In addition, the blending amount of the solvent (C) shown in Tables 7 and 8 includes the copolymer (A) solutions of Examples 1 to 5 and the copolymer (A') solutions of Comparative Examples 1 to 4 and 7. The amount of the solvent contained and the amount of the solvent added during preparation of the resin composition are summed up and described.
Copolymer (A) or copolymer (A') shown in Tables 7 and 8, basic catalyst (B), solvent (C), reactive diluent (D), photopolymerization initiator (E) The content of each component is the content (parts by mass) relative to a total of 100 parts by mass of the copolymer (A) or the copolymer (A') and the reactive diluent (D).

[Solvent resistance evaluation 2]
Each of the resin compositions of Examples 21 to 25 and Comparative Examples 21 to 26 was placed on a square glass substrate (non-alkali glass substrate) measuring 5 cm long and 5 cm wide in plan view, and the thickness after exposure was 2.5 μm. was applied by a spin coating method to form a coating film. Then, the solvent (C) in the coating film was volatilized and removed by heating at 100° C. for 3 minutes.

Next, the coating film was irradiated with ultraviolet rays having a wavelength of 365 nm at an energy dose of 40 mJ/cm ² to be exposed, and the exposed portions were photocured. After that, the coating film was cured by performing a baking treatment at 80° C. or 100° C. for 30 minutes to obtain a cured film. The thickness of the prepared cured film was measured with a profilometer. The thickness at this time was defined as X.
After that, the glass substrate on which the cured film was formed was immersed in 20 g of propylene glycol monomethyl ether acetate (PGMEA) at 23° C. for 15 minutes. After the glass substrate after immersion was vacuum-dried at 40° C. for 30 minutes, the thickness of the coating film was measured with a profilometer. Y was the thickness at this time.

Then, the ratio of the thickness Y of the cured film after immersion in PGMEA to the thickness X of the cured film before immersion in PGMEA was calculated as the remaining film ratio, and the solvent resistance of the cured film was evaluated. That is, the closer the residual film ratio is to 100%, the better the solvent resistance of the cured film. As an evaluation, a film remaining rate of 60% or more was regarded as a pass line. The results are shown in Table 7 or Table 8.
Remaining film rate = (Y/X) x 100 (%)

As shown in Table 7, the cured films of the resin compositions of Examples 21 to 25 had a residual film ratio (%) of 60% or more after immersion in PGMEA when the heating temperature was 80°C or 100°C. Solvent resistance was good.
On the other hand, as shown in Table 8, the cured films of the resin compositions of Comparative Examples 21 to 26 had residual film ratios ( %) was 0%, and the solvent resistance was insufficient.

The resin composition of Comparative Example 25 contains the copolymer (A) of Example 1, but does not contain the basic catalyst (B). Therefore, it is presumed that the group represented by the formula (1) of the structural unit (b) contained in the copolymer (A) was not converted to a group having a dienophile moiety during heat curing. . As a result, it is presumed that the reaction between the group having a dienophile moiety and the conjugated diene moiety of the structural unit (a) did not occur, resulting in insufficient low-temperature curability and insufficient solvent resistance of the cured film.

In the resin composition of Comparative Example 26, although the copolymer (A') of Comparative Example 7 contains the structural unit (b), since it contains a structural unit having a carboxy group derived from methacrylic acid, a basic catalyst ( B) is presumed to be inactivated. As a result, the amount of the dienophile site generated from the group represented by the formula (1) becomes insufficient, and the amount of cross-linking due to the Diels-Alder reaction between the dienophile site and the conjugated diene site cannot be ensured, resulting in the solvent resistance of the cured film. It is presumed that the sex was insufficient.

ADVANTAGE OF THE INVENTION According to this invention, the resin composition which gives the hardened|cured material which has excellent solvent resistance is provided. Further, according to the present invention, an interlayer insulating film made of a cured product having excellent solvent resistance, a color filter having a protective film made of the above cured product, and an image display device provided with a resin cured film made of the above cured product are provided. be done. The resin composition of the present invention can be preferably used as a material for transparent films, protective films, insulating films, overcoats, photospacers, black matrices, black column spacers, color filter resists, and the like.

Claims (15)

a structural unit (a) having a conjugated diene moiety in its side chain;
a structural unit (b) having a group represented by the following formula (1);
contains
A copolymer characterized by not containing a carboxy group.

(In Formula (1), R ¹ and R ² are each independently a hydrocarbon group having 1 to 20 carbon atoms; R ³ and R ⁴ are each independently a hydrogen atom or a 20 hydrocarbon groups.* represents the bonding site.) The structural unit (a) having a conjugated diene site in the side chain is a structural unit derived from a conjugated diene-containing monomer (ma),
2. The copolymer according to claim 1, wherein said conjugated diene moiety is a furan ring. 3. The copolymer according to claim 2, wherein the conjugated diene-containing monomer (ma) is a furan ring-containing (meth)acrylate. R ¹ and R ² of the structural unit (b) are each independently a hydrocarbon group having 1 to 3 carbon atoms, and R ³ and R ⁴ are each independently a hydrogen atom or a methyl group. The copolymer according to any one of claims 1 to 3. The content ratio of the structural unit (a) is 1 to 99 mol%,
5. The copolymer according to any one of claims 1 to 4, wherein the content of the structural unit (b) is 1 to 99 mol%. Further containing other structural units (c),
6. The copolymer according to any one of claims 1 to 5, wherein the other structural unit (c) contains a structural unit derived from an alkyl (meth)acrylate. The content of the structural unit (a) is 1 to 50 mol%,
The content of the structural unit (b) is 1 to 50 mol%,
7. The copolymer according to claim 6, wherein the content of said structural unit (c) is 30 to 98 mol %. The copolymer (A) according to any one of claims 1 to 7,
a basic catalyst (B);
a solvent (C);
A resin composition containing The resin composition according to claim 8, wherein the basic catalyst (B) is a compound represented by the following formula (5).
R ¹¹ N=CR ¹² -NR ¹³ R ¹⁴ (5)
(In the formula (5), R ¹¹ is a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a group represented by —N(R ¹⁵ ) ₂ (wherein R ¹⁵ is a hydrogen atom or a carbon atom two R ¹⁵ may be the same or different, and each of R ¹² , R ¹³ and R ¹⁴ is a hydrogen atom or a carbon atom; It is a hydrocarbon group having an atom number of 1 to 20. Any two or more of R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and two R ¹⁵ groups may combine to form a cyclic structure. good.) The basic catalyst (B) is 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-nonene, and 1,1,3, 10. The resin composition according to claim 8, which is one or more selected from 3-tetramethylguanidine. a reactive diluent (D);
The resin composition according to any one of claims 8 to 10, further comprising a photopolymerization initiator (E). With respect to a total of 100 parts by mass of the copolymer (A) and the reactive diluent (D),
Containing 10 to 90 parts by mass of the copolymer (A),
Containing 0.001 to 1 part by mass of the basic catalyst (B),
Containing 30 to 1000 parts by mass of the solvent (C),
Containing 10 to 90 parts by mass of the reactive diluent (D),
Containing 0.1 to 30 parts by mass of the photopolymerization initiator (E),
The resin composition according to claim 11. An interlayer insulating film comprising a cured product of the resin composition according to any one of claims 8 to 12. A protective film comprising a cured product of the resin composition according to any one of claims 8 to 12. An image display device comprising a cured resin film comprising a cured product of the resin composition according to any one of claims 8 to 12.