Polymer, curable resin composition, and method for producing polymer

Abstract

The purpose of the present invention is to provide a polymer capable of satisfactorily performing development processing and giving a cured product excellent in heat resistance and adhesion, and to provide a curable resin composition containing the polymer. The present invention relates to a polymer having a structural unit (A) having a carboxylic acid group, a structural unit (B) having a phenolic hydroxyl group, a structural unit (C) having a ring structure in the main chain, and a structural unit (D) having a polymerizable unsaturated group.

Description

Polymer, curable resin composition, and method for producing polymer

[0001] The present invention relates to a polymer, a curable resin composition, and a method for producing a polymer. More specifically, the present invention relates to a polymer, a curable resin composition, and a method for producing a polymer that can give a cured product having excellent developability, heat resistance, and adhesion.

[0002] Polymers that can be cured by heat or active energy rays have been widely studied for application to various applications, such as various optical components and electrical and electronic devices, including color filters, inks, printing plates, printed wiring boards, semiconductor elements, photoresists, organic insulating films, and organic protective films used in liquid crystal displays and solid-state imaging devices, and resins and resin compositions excellent in the properties required for each application have been developed. In recent years, optical components, electrical and electronic devices, and the like have become smaller, thinner, and more energy-efficient, and this has led to demands for higher performance in the various components used. In order to meet such demands, research is being conducted on polymers that are even more excellent in various properties.

[0003] For example, various resins and photosensitive resin compositions used in the production of color filters have been proposed (Patent Documents 1 to 5).

[0004] Japanese Patent Application Laid-Open No. 8-194109 Japanese Patent Application Laid-Open No. 2008-31199 Japanese Patent Application Laid-Open No. 2012-82317 Japanese Patent Application Laid-Open No. 2020-126822 International Publication No. 2022 / 270407

[0005] When a cured product is obtained using a photosensitive resin composition, the composition is generally applied to a substrate, the coating film is exposed through a photomask, and the coating film is developed with a developer, followed by thermal curing. In recent years, various developers have been used depending on the components of the resin composition used depending on the application and purpose of the cured product, and strong alkaline developers are sometimes used. However, when a strong alkaline developer is used, there is a problem that the development speed becomes too fast with conventional resins, which actually reduces workability. In addition, there is a problem that the resin dissolves in the developer during development and becomes more likely to flow, resulting in poor adhesion and heat resistance of the cured film obtained after curing.

[0006] In view of the above-described current situation, an object of the present invention is to provide a polymer that can be developed well and can give a cured product that is excellent in heat resistance and adhesion, and a curable resin composition containing the polymer.

[0007] In order to solve the above problems, the present inventors have conducted extensive research on polymers used in curable resin compositions and have found that by having four specific structural units, development can be carried out well even when development is carried out using a strong alkaline developer, and a cured product having excellent heat resistance and adhesion can be obtained, which has led to the completion of the present invention.

[0008] That is, the present invention includes the following aspects. <1> A polymer comprising a structural unit (A) having a carboxylic acid group, a structural unit (B) having a phenolic hydroxyl group, a structural unit (C) having a ring structure in the main chain, and a structural unit (D) having a polymerizable unsaturated group. <2> The polymer according to <1> above, wherein the structural unit (D) does not have a urethane bond. <3> The polymer according to <1> or <2> above, wherein the carboxylic acid acid value is 1 to 40 mg KOH / g and the phenolic hydroxyl group acid value is 40 to 200 mg KOH / g. <4> The polymer according to any one of <1> to <3> above, wherein the polymer comprises a structural unit (E) derived from an aromatic monomer (excluding the structural unit (B) having a phenolic hydroxyl group). <5> The polymer according to any one of <1> to <4> above, wherein the content of the structural unit (C) having a ring structure in the main chain is 5 to 60% by mass, relative to 100% by mass of all structural units of the polymer. <6> The polymer according to any one of <1> to <5> above, wherein the structural unit (C) having a ring structure in the main chain is a structural unit derived from a maleimide-based monomer. <7> A curable resin composition comprising the polymer according to any one of <1> to <6> above, and a polymerization initiator. <8> A method for producing a polymer, the method comprising: a step (1) of polymerizing monomer components including an unsaturated carboxylic acid-based monomer (a), a monomer (b) having a phenolic hydroxyl group, and a monomer (c) that introduces a ring structure into the main chain; and a step (2) of reacting the polymer obtained in the step (1) with a compound (d) having a group reactive with a carboxy group and / or a phenolic hydroxyl group and a polymerizable unsaturated group, thereby introducing a polymerizable unsaturated group into a side chain of the polymer. <9> The method for producing a polymer according to the above item <8>, wherein the polymer has a carboxylic acid acid value of 1 to 40 mgKOH / g and a phenolic hydroxyl group acid value of 40 to 200 mgKOH / g. <10> The method for producing a polymer according to the above item <8> or <9>, wherein the step (2) is carried out in the presence of a tertiary phosphine.

[0009] The polymer of the present invention can provide a cured product having excellent developability, heat resistance, and adhesion, and is suitable for use as a material for various optical components and electrical and electronic components.

[0010] 1 is a graph showing the change over time in the reaction rate of glycidyl methacrylate with respect to the base polymer during the synthesis of the polymers of Example 3 and Comparative Example 3.

[0011] The present invention will be described in detail below. A combination of two or more of the individual preferred embodiments of the present invention described below is also a preferred embodiment of the present invention. Furthermore, in this specification, "(meth)acrylic acid" means "acrylic acid and / or methacrylic acid," and "(meth)acrylate" means "acrylate and / or methacrylate."

[0012] 1. Polymer The polymer of the present invention is characterized by having a structural unit (A) having a carboxylic acid group, a structural unit (B) having a phenolic hydroxyl group, a structural unit (C) having a ring structure in the main chain, and a structural unit (D) having a polymerizable unsaturated group. The reasons why the polymer has excellent developability, heat resistance, and adhesion are believed to be as follows. That is, by having the structural unit (B) having a phenolic hydroxyl group in addition to the structural unit (A) having a carboxylic acid group, the acid strength of the polymer is appropriately reduced. When using an alkaline developer, particularly a strong alkaline developer, the development rate is suppressed, allowing for an appropriate development time, and dissolution and flow of the coating film during development can be suppressed, resulting in a cured product with excellent heat resistance. Furthermore, by having the structural unit (B), π-π stacking by the aromatic ring can be achieved, thereby improving the adhesion of the cured product to glass substrates and the like. Furthermore, by further having the structural unit (C) having a ring structure in the main chain, the heat resistance of the cured product can be improved. Furthermore, by including the structural unit (D) having a polymerizable unsaturated group, the curability of the polymer is improved, and the adhesiveness and heat resistance of the cured product can be further improved.

[0013] Each structural unit constituting the polymer of the present invention will be described. <Structural Unit (A)> The polymer has a structural unit (A) having a carboxylic acid group. By having the structural unit (A), the polymer exhibits alkali solubility.

[0014] A polymer having the structural unit (A) can be obtained, for example, by polymerizing a monomer component containing an unsaturated carboxylic acid monomer (a). Thus, the structural unit (A) is preferably a structural unit derived from an unsaturated carboxylic acid monomer. The structural unit derived from an unsaturated carboxylic acid monomer corresponds, for example, to a structure in which the polymerizable double bond of the unsaturated carboxylic acid monomer is opened by a polymerization reaction. The structure in which the polymerizable double bond is opened is, for example, a structure in which a carbon-carbon double bond (C═C) becomes a single bond (—C—C—).

[0015] Examples of the unsaturated carboxylic acid monomer (a) include unsaturated monocarboxylic acids such as (meth)acrylic acid, crotonic acid, cinnamic acid, and vinylbenzoic acid; unsaturated polycarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid; long-chain unsaturated monocarboxylic acids in which the unsaturated group and the carboxyl group are chain-extended, such as β-carboxyethyl (meth)acrylate, mono(2-acryloyloxyethyl) succinate, and mono(2-methacryloyloxyethyl) succinate; and unsaturated acid anhydrides such as maleic anhydride and itaconic anhydride. Of these, unsaturated monocarboxylic acids are preferred, (meth)acrylic acid is more preferred, and methacrylic acid is most preferred, in view of the good heat resistance of the cured product.

[0016] The polymer may have one or more types of the structural unit (A). The content of the structural unit (A) in the polymer is preferably 0.01 to 20% by mass, more preferably 0.5 to 15% by mass, and even more preferably 1 to 10% by mass, relative to 100% by mass of all structural units of the polymer, in terms of being able to appropriately lower the acid strength and reduce the dielectric loss tangent.

[0017] Furthermore, the content of the structural unit (A) is preferably 0.1 to 30 mol %, more preferably 0.5 to 20 mol %, and most preferably 1 to 10 mol %, relative to 100 mol % of all structural units in the polymer.

[0018] <Structural Unit (B)> The polymer contains a structural unit (B) having a phenolic hydroxyl group. By containing the structural unit (B), the development rate can be appropriately adjusted. The phenolic hydroxyl group refers to a hydroxyl group directly bonded to a carbon atom in an aromatic ring.

[0019] The structural unit (B) is preferably a structural unit represented by the following general formula (B-1):

[0020] (In the formula, R １ represents a hydrogen atom or a methyl group. ２ represents a direct bond or a divalent group; and a represents an integer of 1 to 5.

[0021] R in the above general formula (B-1) １ A methyl group is preferred in that the heat resistance of the cured product is good.

[0022] R in the above general formula (B-1) ２ The divalent group represented by the formula (I) includes a divalent hydrocarbon group, -O-, -CO-, -COO-, -NH-, -S-, -SO-, -SO ２ -, -NHCO-, or a group consisting of a combination thereof.

[0023] Examples of the divalent hydrocarbon group include a divalent aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group.

[0024] Examples of the divalent aliphatic hydrocarbon group include alkylene groups such as methylene, ethylene, n-propylene, i-propylene, n-butylene, s-butylene, t-butylene, n-pentylene, neopentylene, n-hexylene, n-heptylene, n-octylene, n-nonylene, and n-decylene.

[0025] Examples of the divalent alicyclic hydrocarbon group include cycloalkylene groups such as a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a norbornylene group, an adamantylene group, a tricyclodecanylene group, and a tetracyclodecanylene group; and cycloalkenylene groups such as a cyclopropenylene group, a cyclobutenylene group, and a cyclopentenylene group.

[0026] Examples of the divalent aromatic hydrocarbon group include a phenylene group, a naphthylene group, a tolylene group, and a biphenylene group.

[0027] The divalent hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 5 carbon atoms.

[0028] In the divalent hydrocarbon group, at least one atom constituting the hydrocarbon group may be substituted with an oxygen atom, a nitrogen atom, or a sulfur atom.

[0029] Among these, the divalent group is preferably a divalent hydrocarbon group, —COO—, or a group containing a divalent hydrocarbon group and —COO—, in terms of good adhesion to the cured product, and —R ａ１ -COO-R ａ２ - (R ａ１ and R ａ２ are the same or different and represent a direct bond or an alkylene group.) is more preferable, and —COO— is even more preferable.

[0030] R in the above general formula (B-1) ２ is preferably a direct bond or —COO— in that the cured product has good heat resistance and adhesion.

[0031] In general formula (B-1) above, a represents the number of hydroxyl groups and is preferably an integer of 1 to 3, more preferably an integer of 1 or 2, and even more preferably 1. The bonding position of the hydroxyl group is not particularly limited, but the para position relative to the bonding position to the main chain on the benzene ring is preferred, in that alkaline developability is easily exhibited.

[0032] The polymer having the structural unit (B) can be obtained, for example, by polymerizing a monomer component containing a monomer (b) having a phenolic hydroxyl group. Examples of the monomer (b) include hydroxyphenyl (meth)acrylate, 4-hydroxystyrene, and p-isopropenylphenol. Among these, hydroxyphenyl (meth)acrylate is preferred, and hydroxyphenyl methacrylate is more preferred, in view of the excellent heat resistance and adhesion of the cured product.

[0033] The polymer may have one or more types of the structural unit (B). In terms of good developability and adhesion of the cured product, the content of the structural unit (B) is preferably 1 to 80% by mass, more preferably 5 to 60% by mass, and even more preferably 10 to 50% by mass, relative to 100% by mass of all structural units of the polymer.

[0034] Furthermore, the content of the structural unit (B) is preferably 1 to 90 mol %, more preferably 5 to 70 mol %, and most preferably 10 to 50 mol %, relative to 100 mol % of all structural units in the polymer.

[0035] <Structural Unit (C)> The polymer has a structural unit (C) having a ring structure in the main chain. By having the structural unit (C), a cured product with excellent heat resistance can be obtained. Examples of the ring structure include an imide ring, a tetrahydrofuran ring, and a lactone ring.

[0036] A polymer having the structural unit (C) can be obtained, for example, by polymerizing a monomer component containing a monomer (c) that introduces a ring structure into the main chain. Examples of the monomer (c) include a monomer having a double bond-containing ring structure in the molecule, a monomer that undergoes cyclopolymerization to form a polymer having a ring structure in the main chain, and a monomer that forms a ring structure after polymerization. Among these, from the viewpoint of good heat resistance, the monomer (c) is preferably at least one monomer selected from the group consisting of maleimide-based monomers, dialkyl-2,2'-(oxydimethylene)diacrylate-based monomers, and α-(unsaturated alkoxyalkyl)acrylate-based monomers. In terms of further improving heat resistance, a maleimide-based monomer is more preferred, and an N-substituted maleimide-based monomer is even more preferred. Thus, the structural unit (C) is preferably a structural unit derived from the monomer (c).

[0037] The maleimide monomer includes maleimide and maleimide derivatives such as N-substituted maleimide monomers.

[0038] Examples of the N-substituted maleimide monomer include those described in JP-A-2023-75463. Among them, from the viewpoint of heat resistance, N-phenylmaleimide, N-benzylmaleimide, and N-cyclohexylmaleimide are preferred, and N-phenylmaleimide is more preferred.

[0039] Examples of the dialkyl-2,2'-(oxydimethylene)diacrylate monomer include the compounds described in JP-A-2023-75463. Of these, dimethyl-2,2'-[oxybis(methylene)]bis-2-propenoate is preferred from the viewpoints of transparency, dispersibility, and ease of industrial availability.

[0040] Examples of the α-(unsaturated alkoxyalkyl)acrylate monomer include the α-(allyloxymethyl)acrylate monomers described in JP-A-2023-75463. Among these, methyl α-allyloxymethylacrylate (also referred to as methyl-(α-allyloxymethyl)acrylate) is preferred from the viewpoints of transparency, dispersibility, and ease of industrial availability.

[0041] Further, examples of the monomer (c) include 2-(hydroxyalkyl)acrylic acid alkyl esters. 2-(hydroxyalkyl)acrylic acid alkyl esters can react with (meth)acrylic acid to form a lactone ring structure in the main chain. Examples of the 2-(hydroxyalkyl)acrylic acid alkyl esters include methyl 2-(1-hydroxymethyl)acrylate, ethyl 2-(1-hydroxymethyl)acrylate, isopropyl 2-(1-hydroxymethyl)acrylate, n-butyl 2-(1-hydroxymethyl)acrylate, t-butyl 2-(1-hydroxymethyl)acrylate, and 2-ethylhexyl 2-(1-hydroxymethyl)acrylate.

[0042] The polymer may have one or more types of the structural unit (C). In order to obtain a cured product with good heat resistance, the content of the structural unit (C) is preferably 1 to 60% by mass, more preferably 5 to 50% by mass, and even more preferably 20 to 50% by mass, relative to 100% by mass of all structural units of the polymer.

[0043] Furthermore, the content of the structural unit (C) is preferably 1 to 60 mol %, more preferably 5 to 50 mol %, and most preferably 20 to 50 mol %, relative to 100 mol % of all structural units in the polymer.

[0044] <Structural Unit (D)> The polymer includes a structural unit (D) having a polymerizable unsaturated group. By including the structural unit (D), the curability of the polymerizable polymer is improved, and the heat resistance and adhesion of the resulting cured product are improved.

[0045] Examples of the polymerizable unsaturated group include groups having a polymerizable double bond, such as a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, or a methacryloyloxy group. Among these, an acryloyl group or a methacryloyl group is preferred because of its good polymerization reactivity.

[0046] The structural unit (D) preferably does not have a urethane bond, since a urethane bond has low bond energy, and if the polymer contains a urethane bond, the heat resistance decreases.

[0047] In view of good polymerization reactivity, the structural unit (D) is preferably at least one selected from the group consisting of structural unit (D1) represented by general formula (D-1) below, structural unit (D2) represented by general formula (D-2) below, and structural unit (D3) represented by general formula (D-3) below. Of these, in view of good adhesion of the cured product, the structural unit (D3) represented by general formula (D-3) above is more preferred.

[0048] (In the formula, R １１ represents a hydrogen atom or a methyl group. １２ represents a direct bond or a divalent group. １３ ~R １６ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. １７ represents a group containing a polymerizable unsaturated group.

[0049] (In the formula, R ２１ represents a hydrogen atom or a methyl group. ２２ represents a direct bond or a divalent group. ２３ ~R ２６ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ２７ represents a group containing a polymerizable unsaturated group.

[0050] (In the formula, R ３１ represents a hydrogen atom or a methyl group. ３２ represents a direct bond or a divalent group. ３３ represents a divalent hydrocarbon group having a hydroxyl group. ３４represents a group containing a polymerizable unsaturated group.

[0051] In the above general formula (D-1), R １１ R is preferably a methyl group, since the heat resistance of the cured product is good. １２ The divalent group represented by the formula (I) is the same as the above-mentioned R ２ Among them, groups similar to the divalent group represented by R １２ The divalent group represented by R is preferably a divalent hydrocarbon group. １２ is preferably a direct bond or a divalent hydrocarbon group, and particularly preferably a direct bond.

[0052] R １３ ~R １６ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The alkyl group preferably has 1 to 3 carbon atoms, and more preferably 1 or 2 carbon atoms.

[0053] R １７ Examples of the group containing a polymerizable unsaturated group represented by the formula: ｂ１ -X(R ｂ１ represents a direct bond or a divalent group. X represents a polymerizable unsaturated group. ｂ１ The divalent group represented by the formula (I) is the same as the above-mentioned R ２ Among these, in view of the excellent adhesion and heat resistance of the cured product, a divalent hydrocarbon group, -O-, -COO-, -CO-, or a group consisting of a combination thereof is preferred, and -O-, a divalent hydrocarbon group, or a group consisting of a combination of -O- and a divalent hydrocarbon group is more preferred.

[0054] Examples of the polymerizable unsaturated group represented by X include those mentioned above, but a (meth)acryloyl group (an acryloyl group and / or a methacryloyl group) is preferred in terms of good polymerization reactivity.

[0055] R １７ The group containing a polymerizable unsaturated group represented by the formula: ｂ２ =CH ２ (R ｂ２ represents a hydrogen atom or a methyl group.

[0056] The structural unit (D1) represented by the above general formula (D-1) can be obtained, for example, by adding a polymerizable monomer having an aziridine group to the carboxy group of the above structural unit (A).

[0057] Examples of the polymerizable monomer having an aziridine group include the aziridine group-containing polymerizable monomers described in JP-A-01-118573, such as N-(meth)acryloylaziridine and 2-(1-aziridinyl)ethyl(meth)acrylate.

[0058] In the above general formula (D-2), R ２１ R is preferably a methyl group, since the heat resistance of the cured product is good. ２２ The divalent group represented by the formula (I) is the same as the above-mentioned R ２ Among them, groups similar to the divalent group represented by R ２２ The divalent group represented by R is preferably a divalent hydrocarbon group. ２２ is preferably a direct bond or a divalent hydrocarbon group, and particularly preferably a direct bond.

[0059] R ２３ ~R ２６ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The alkyl group preferably has 1 to 3 carbon atoms, and more preferably 1 or 2 carbon atoms.

[0060] R ２７ The group containing a polymerizable unsaturated group represented by the formula (I) is the same as the group represented by the formula (I) above. １７ The groups may be the same as those containing a polymerizable unsaturated group represented by the following formula:

[0061] The structural unit (D2) represented by the above general formula (D-2) can be obtained, for example, by adding a polymerizable monomer having an oxazoline group to the carboxy group of the above structural unit (A).

[0062] Examples of the polymerizable monomer having an oxazoline group include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, and 2-isopropenyl-4,5-dimethyl-2-oxazoline.

[0063] In the above general formula (D-3), R ３１ R is preferably a methyl group, since the heat resistance of the cured product is good. ３２ The divalent group represented by the formula (I) is the same as the above-mentioned R ２ Among them, groups similar to the divalent group represented by R ３２ The divalent group represented by R is preferably a divalent hydrocarbon group. ３２ is preferably a direct bond or a divalent hydrocarbon group, and particularly preferably a direct bond.

[0064] R ３３ The divalent hydrocarbon group having a hydroxyl group represented by the formula (I) is preferably a divalent saturated aliphatic hydrocarbon group or alicyclic hydrocarbon group having a hydroxyl group, and from the viewpoint of reactivity, is more preferably a divalent saturated aliphatic hydrocarbon group having a hydroxyl group. The divalent hydrocarbon group may have a substituent. The divalent hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 3 to 6 carbon atoms. Examples of the substituent include monovalent hydrocarbon groups such as a methyl group.

[0065] The above R ３３ Preferred examples of the divalent hydrocarbon group having a hydroxyl group represented by the formula (I) include the following:

[0066] (In the formula, R ｃ１ ~R ｃ５ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ｄ１ ~R ｄ９are the same or different and represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

[0067] R ３４ The group containing a polymerizable unsaturated group represented by the formula (I) is the same as the group represented by the formula (I) above. １７ Among them, the same as the group containing a polymerizable unsaturated group represented by —O—CO—CR ｂ２ =CH ２ (R ｂ２ represents a hydrogen atom or a methyl group.

[0068] The structural unit (D3) represented by the above general formula (D-3) can be obtained, for example, by adding a polymerizable monomer having an epoxy group to the carboxy group of the above structural unit (A).

[0069] Examples of the polymerizable monomer having an epoxy group include glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, β-ethylglycidyl (meth)acrylate, vinylbenzyl glycidyl ether, allyl glycidyl ether, and (3,4-epoxycyclohexyl)methyl (meth)acrylate.

[0070] The polymer may have one or more types of the structural unit (D). The content of the structural unit (D) is preferably 1 to 80% by mass, more preferably 5 to 60% by mass, and even more preferably 10 to 40% by mass, relative to 100% by mass of all structural units of the polymer, in order to further improve the adhesion and heat resistance of the resulting cured product.

[0071] Furthermore, the content of the structural unit (D) is preferably 0.1 to 80 mol %, more preferably 1 to 60 mol %, and most preferably 5 to 40 mol %, relative to 100 mol % of all structural units in the polymer.

[0072] <Structural Unit (E)> The polymer preferably further comprises a structural unit (E) derived from an aromatic monomer (excluding the structural unit (B) having a phenolic hydroxyl group). By including the structural unit (E), the π-π stacking action of the aromatic ring can be utilized to further improve the adhesion of the cured product. The structural unit (E) is preferably a structural unit derived from an aromatic monomer that does not have an ester bond, as this can further improve heat resistance and adhesion.

[0073] The structural unit (E) is a structural unit derived from an aromatic monomer other than the structural unit (B). A polymer having the structural unit (E) can be obtained by polymerizing a monomer component containing an aromatic monomer (e). The aromatic monomer (e) preferably does not have an ester bond. The aromatic monomer (e) is a monomer other than an aromatic monomer that does not have a phenolic hydroxyl group, and examples of the aromatic monomer (e) include aromatic vinyl monomers such as styrene, vinyltoluene, α-methylstyrene, and methoxystyrene.

[0074] The polymer may have one or more types of the structural unit (E). The content of the structural unit (E) is preferably 1 to 80% by mass, more preferably 5 to 60% by mass, and even more preferably 10 to 40% by mass, relative to 100% by mass of all structural units of the polymer, in order to achieve good adhesion of the cured product.

[0075] Furthermore, the content of the structural unit (E) is preferably 0.1 to 80 mol %, more preferably 1 to 60 mol %, and most preferably 5 to 40 mol %, relative to 100 mol % of all structural units in the polymer.

[0076] <Structural Unit (F)> The polymer may further include a structural unit (F) other than the structural units (A) to (E) described above. Examples of the structural unit (F) include structural units derived from the following monomer (f): hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 2,3-hydroxypropyl (meth)acrylate; Methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, s-butyl (meth)acrylate, n-amyl (meth)acrylate, s-amyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, tridecyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, tricyclodecanyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate (Meth)acrylic acid ester monomers such as tungsten, 4-(1-methoxy)ethoxycyclohexyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, 1,4-dioxaspiro[4,5]dec-2-yl methacrylic acid, (meth)acryloylmorpholine, 4-(meth)acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl-2-methyl-2-isobutyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl-2-methyl-2-cyclohexyl-1,3-dioxolane, and 4-(meth)acryloyloxymethyl-2,2-dimethyl-1,3-dioxolane;

[0077] 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]ethyl methacrylate, 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]ethyl acrylate, 3-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]propyl methacrylate, 3-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]propyl acrylate acrylate, 4-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]butyl methacrylate, 4-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl]butyl acrylate, 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yloxy]ethyl methacrylate, 2-[2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yloxy]ethyl methacrylate ]ethyl acrylate, 2-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl methacrylate, 2-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl acrylate, 4-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]butyl methacrylate, 4-[3-{2-(6 -hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]butyl acrylate, 2-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl methacrylate, 2-[3-{2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazol-5-yl}propanoyloxy]ethyl acrylate, 2-(methacryloyloxy)ethyl 2-(6-hydroxybenzo[1,benzotriazole-based monomers such as 2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate, 2-(acryloyloxy)ethyl 2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate, 4-(methacryloyloxy)butyl 2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate, and 4-(acryloyloxy)butyl 2-(6-hydroxybenzo[1,3]dioxol-5-yl)-2H-benzotriazole-5-carboxylate (e.g., RUVA-93 (manufactured by Otsuka Chemical Co., Ltd.), DAINSORB T-31 (manufactured by Daiwa Chemical Industry Co., Ltd.), etc.);

[0078] Macromonomers having a (meth)acryloyl group at one end of the polymer molecular chain, such as polystyrene, polymethyl (meth)acrylate, polyethylene oxide, polypropylene oxide, polysiloxane, polycaprolactone, and polycaprolactam; conjugated dienes such as 1,3-butadiene, isoprene, and chloroprene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, and vinyl benzoate; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, cyclohexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, methoxypolyethylene glycol vinyl ether, 2-hydroxyethyl vinyl ether, and 4-hydroxybutyl vinyl ether; N-vinyl compounds such as N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylimidazole, N-vinylmorpholine, and N-vinylacetamide; Unsaturated isocyanates such as isocyanatoethyl (meth)acrylate and allyl isocyanate; and the like.

[0079] The polymer may have one or more types of the structural unit (F). In terms of adjusting developability and cured product properties, the content of the structural unit (F) is preferably 1 to 80% by mass, more preferably 5 to 60% by mass, and even more preferably 10 to 40% by mass, relative to 100% by mass of all structural units of the polymer.

[0080] Furthermore, the content of the structural unit (F) is preferably 1 to 80 mol %, more preferably 5 to 60 mol %, and most preferably 10 to 40 mol %, relative to 100 mol % of all structural units in the polymer.

[0081] The polymer preferably has a carboxylic acid acid value of 1 to 40 mgKOH / g and a phenolic hydroxyl group acid value of 40 to 200 mgKOH / g. When the polymer has an acid value within the above ranges, the development rate during development becomes favorable, and the adhesion of the resulting cured film can be improved.

[0082] The carboxylic acid value of the polymer is more preferably 5 to 35 mgKOH / g, and even more preferably 10 to 30 mgKOH / g, in order to appropriately reduce the acid strength. The carboxylic acid value is an acid value related to the structural unit (A) and is a value obtained by measurement using the method described in the Examples below.

[0083] The acid value of the phenolic hydroxyl group of the polymer is more preferably 50 to 180 mgKOH / g, and even more preferably 60 to 150 mgKOH / g, in terms of good developability and adhesion of the cured product. The acid value of the phenolic hydroxyl group is an acid value related to the structural unit (B), and is a value obtained by measurement by the method described in the Examples below.

[0084] The polymerizable double bond equivalent of the polymer is preferably 300 to 100,000 g / equivalent, more preferably 400 to 5,000 g / equivalent, and even more preferably 500 to 2,500 g / equivalent, in that this further improves the adhesion and heat resistance of the resulting cured product.

[0085] The polymerizable double bond herein refers to a double bond having radical polymerizability, i.e., a polymerizable double bond represented by a (meth)acryloyl group, and a double bond formed by adding tetrahydrophthalic anhydride to a hydroxyl group, for example, is not included in the calculation of the polymerizable double bond equivalent because it has no reactivity.

[0086] The polymerizable double bond equivalent is the mass of the solid content of the polymer solution per 1 mol of polymerizable double bonds in the polymer. The mass of the solid content of the polymer solution is the mass of the monomer components constituting the polymer. The polymerizable double bond equivalent is determined by dividing the mass (g) of the polymer solid content of the polymer solution by the amount (mol) of polymerizable double bonds in the polymer.

[0087] The weight average molecular weight of the polymer is not particularly limited, but in terms of good developability, it is preferably from 1,000 to 100,000, more preferably from 2,500 to 30,000, and even more preferably from 5,000 to 20,000. The weight average molecular weight is a value obtained by measurement by gel permeation chromatography (GPC) using the method described in the examples.

[0088] 2. Method for Producing Polymer The method for producing the polymer of the present invention is not particularly limited as long as it can produce a polymer having the above-mentioned structural units (A) to (D), and examples thereof include a method of polymerizing monomer components containing monomers that provide each of the above-mentioned structural units, and a method of polymerizing polymer components to obtain a base polymer and then subjecting a group possessed by the base polymer to an addition reaction with another compound to obtain a polymer having predetermined structural units. Among these, the method for producing the polymer preferably includes, in terms of efficient production of the polymer, a step (1) of polymerizing monomer components including an unsaturated carboxylic acid monomer (a), a monomer (b) having a phenolic hydroxyl group, and a monomer (c) that introduces a ring structure into the main chain, and a step (2) of reacting the polymer obtained in the step (1) with a compound (d) having a group reactive with a carboxyl group and / or a phenolic hydroxyl group and a polymerizable unsaturated group to introduce a polymerizable unsaturated group into the side chain of the polymer. By using an unsaturated carboxylic acid monomer (a) and a monomer (b) having a phenolic hydroxyl group as the acid groups of the polymer, the reaction of the compound (d) in step (2) proceeds rapidly, allowing the desired polymer to be produced in high yield. Furthermore, the carboxylic acid with high acid strength reacts preferentially, allowing phenol to remain in the polymer. This method for producing a polymer also includes step (1) of polymerizing monomer components including the unsaturated carboxylic acid monomer (a), the monomer (b) having a phenolic hydroxyl group, and the monomer (c) that introduces a ring structure into the main chain, and step (2) of reacting the polymer obtained in step (1) with a compound (d) having a group reactive with a carboxyl group and / or a phenolic hydroxyl group and a polymerizable unsaturated group to introduce a polymerizable unsaturated group into the side chain of the polymer.

[0089] Step (1) The unsaturated carboxylic acid monomer (a), the monomer (b) having a phenolic hydroxyl group, and the monomer (c) introducing a ring structure into the main chain in the step (1) are as described above. The monomer components polymerized in the step (1) may contain the above-mentioned other monomers (monomers (e) or (f)) in addition to the above-mentioned monomers (a), (b), and (c). The amount of each monomer may be appropriately adjusted by a known method so as to achieve the content ratio of the above-mentioned structural units in the polymer to be obtained.

[0090] The polymerization in step (1) is not particularly limited, and commonly used techniques such as bulk polymerization, solution polymerization, and emulsion polymerization can be used. Among these, solution polymerization is preferred because it is industrially advantageous and allows for easy structural adjustment such as molecular weight. Furthermore, the polymerization mechanism of the monomer component can be based on a polymerization method such as radical polymerization, anionic polymerization, cationic polymerization, or coordination polymerization, but a polymerization method based on a radical polymerization mechanism is preferred because of its industrial advantages. Furthermore, the molecular weight of the polymer obtained by polymerizing the monomer component can be controlled by adjusting the amount and type of polymerization initiator, the polymerization temperature, the type and amount of chain transfer agent, and the like.

[0091] Examples of the polymerization initiator include organic peroxides such as t-butylperoxy-2-ethylhexanoate and azo compounds such as 2,2'-azobis(isobutyronitrile), which are commonly used as polymerization initiators. Examples of the chain transfer agent include mercaptan-based chain transfer agents such as alkyl mercaptans, mercaptocarboxylic acids, and mercaptocarboxylic acid esters, which are commonly used as chain transfer agents. These may be used alone or in combination of two or more. The amounts of these agents added can be appropriately determined using known methods.

[0092] Examples of the solvent used in the polymerization include aromatic hydrocarbon solvents such as toluene and xylene; alcohol solvents such as methanol, ethanol, propanol, isopropanol, ethylene glycol, and ethylene glycol monomethyl ether; aliphatic hydrocarbon solvents such as hexane, pentane, heptane, and cyclohexane; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; halogenated hydrocarbon solvents such as chlorobenzene, dichloromethane, chloroform, and 1,2-dichloroethane; nitrile solvents such as acetonitrile, propionitrile, and valeronitrile; methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, cellosolve acetate, carbitol acetate, (di)propylene glycol monomethyl ether acetate, (di)methyl glutarate, (di)methyl succinate, and (di)adipic acid. Examples of suitable solvents include ester-based solvents such as methyl ether; amide-based solvents such as dimethylformamide (DMF), dimethylacetamide, and N-methylpyrrolidone; ether-based solvents such as diethyl ether, diisopropyl ether, 1,2-dimethoxyethane (DME), 1,4-dioxane, tetrahydrofuran (THF), tetrahydropyran (THP), anisole, diethylene glycol dimethyl ether (diglyme), diethylene glycol ethyl ether (carbitol), cyclopentyl methyl ether (CPME), propylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether; fluorine-based solvents such as perfluorohexane, perfluorocyclohexane, pentafluorobenzene, and octafluorotoluene; cellosolve-based solvents such as cellosolve and butyl cellosolve; DMSO, nitromethane, and the like. These may be used alone or in combination of two or more. The amount of the solvent used is not particularly limited and can be appropriately determined using known methods.

[0093] In the polymerization reaction, a commonly used additive such as a catalyst may be used. The polymerization reaction is preferably carried out in an inert gas atmosphere such as nitrogen or argon with a low oxygen concentration.

[0094] Regarding the conditions for the polymerization reaction, the polymerization temperature may be appropriately set depending on the type and amount of the monomers used, the type and amount of the polymerization initiator, etc., and is, for example, preferably 40 to 140° C., more preferably 50 to 120° C. Similarly, the polymerization time can also be appropriately set and is, for example, preferably 1 to 15 hours, more preferably 2 to 11 hours.

[0095] Step (2) The polymer obtained in the step (1) is reacted with a compound (d) having a group reactive with a carboxy group and / or a phenolic hydroxyl group and a polymerizable unsaturated group to introduce a polymerizable unsaturated group into the side chain of the polymer.

[0096] The polymer obtained in the above step (1) has a carboxy group and a phenolic hydroxyl group. In step (2), the polymer is reacted with a compound (d) having a group reactive with a carboxy group and / or a phenolic hydroxyl group and a polymerizable unsaturated group.

[0097] Examples of the group that reacts with the carboxy group and / or phenolic hydroxyl group include an epoxy group, a hydroxyl group, an amino group, an aziridine group, an oxazoline group, etc. Among these, an epoxy group is preferred in that it provides good adhesion to the cured product.

[0098] Examples of the polymerizable unsaturated group in the compound (d) include those mentioned above, and a (meth)acryloyl group is preferred.

[0099] Specific examples of the compound (d) include epoxy group-containing compounds such as glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, β-ethylglycidyl (meth)acrylate, vinylbenzyl glycidyl ether, allyl glycidyl ether, (3,4-epoxycyclohexyl)methyl (meth)acrylate, and vinylcyclohexene oxide.

[0100] The amount of compound (d) used in the step (2) is preferably 1 to 160 parts by mass, more preferably 5 to 100 parts by mass, and even more preferably 10 to 50 parts by mass, relative to 100 parts by mass of the polymer.

[0101] The reaction in step (2) is preferably carried out in the presence of a tertiary phosphine, which allows the addition reaction between the polymer and compound (d) to proceed smoothly, thereby enabling efficient introduction of polymerizable unsaturated groups into the side chains of the polymer.

[0102] Examples of the tertiary phosphine include trimethylphosphine, tributylphosphine, tricyclophosphine, triphenylphosphine, etc. Among these, triphenylphosphine is preferred because of its good reactivity.

[0103] The amount of the tertiary phosphine used is not particularly limited, but in terms of appropriately promoting the addition reaction, it is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 1 part by mass, relative to 100 parts by mass of the polymer.

[0104] In the above step (2), commonly used additives such as a catalyst other than tertiary phosphines, a polymerization inhibitor, a solvent, etc. may be further used. The additives may be known. The amount of each additive used may also be appropriately selected from known techniques.

[0105] The reaction in step (2) may be carried out by introducing an inhibiting gas into the reaction system or by adding an inhibitor. Introducing an inhibiting gas into the reaction system or adding an inhibitor can prevent gelation during the addition reaction. Examples of inhibiting gases include air and oxygen-nitrogen mixed gases. However, bubbling an oxygen-nitrogen mixed gas with an oxygen concentration of 5 to 10% by volume is preferred, as it allows the reaction to proceed safely outside the explosive range.

[0106] The reaction temperature in the above step (2) is not particularly limited, but is, for example, preferably 90 to 140° C., more preferably 100 to 130° C., and even more preferably 110 to 120° C. The reaction time is not particularly limited, but is, for example, preferably 2 to 20 hours, more preferably 5 to 18 hours, and even more preferably 10 to 15 hours.

[0107] In addition to the above-mentioned methods, examples of methods for introducing a polymerizable unsaturated group into a side chain include a method in which, in step (1), a monomer component containing a hydroxyl group-containing monomer such as the above-mentioned hydroxyalkyl (meth)acrylate is polymerized together with the above-mentioned monomers (a) to (c) as the monomer component to obtain a polymer having a hydroxyl group, and then a compound having a group reactive with a hydroxyl group and a polymerizable unsaturated group is reacted to introduce the polymerizable unsaturated group into the side chain of the polymer.

[0108] Examples of the group that reacts with a hydroxyl group include a carboxy group, an isocyanate group, and an isothiocyanate group.

[0109] Examples of the compound having a group reactive with a hydroxyl group and a polymerizable unsaturated group include the above-mentioned unsaturated isocyanates.

[0110] The reaction between the polymer having a hydroxyl group and the compound having a group reactive with a hydroxyl group and a polymerizable unsaturated group is not particularly limited, and may be carried out by a method appropriately selected from known methods.

[0111] The method for producing the polymer may include other steps in addition to the reaction step described above. Examples of the other steps include an aging step, a neutralization step, a dilution step, a drying step, a concentration step, and a purification step. These steps can be carried out by known methods.

[0112] 3. Second Polymer The present invention also relates to a polymer (also referred to as "Polymer X") characterized by having a structural unit (A') derived from an unsaturated carboxylic acid monomer, a structural unit (B') having a phenolic hydroxyl group, and a structural unit (D') having a polymerizable unsaturated group. Because such a polymer also has a carboxy group and a phenolic hydroxyl group, the development rate can be appropriately adjusted and a cured product with excellent adhesion can be obtained.

[0113] In the polymer X, the structural unit (A'), the structural unit (B'), and the structural unit (D') may be the same as the structural unit (A), the structural unit (B), and the structural unit (D) in the polymer described above, respectively.

[0114] The content of the structural unit (A') is preferably 0.01 to 20% by mass, more preferably 0.5 to 15% by mass, and even more preferably 1 to 10% by mass, relative to 100% by mass of all structural units of polymer X.

[0115] The content of the structural unit (B') is preferably 1 to 80% by mass, more preferably 5 to 60% by mass, and even more preferably 10 to 50% by mass, relative to 100% by mass of all structural units of polymer X.

[0116] The content of the structural unit (D') is preferably 1 to 80 mass %, more preferably 5 to 60 mass %, and even more preferably 10 to 40 mass %, relative to 100 mass % of all structural units of polymer X.

[0117] The polymer X may further include a structural unit (E') similar to the structural unit (E) described above, or a structural unit (F') similar to the structural unit (F) described above. The polymer X does not include a structural unit similar to the structural unit (C) described above.

[0118] The content of the structural unit (E') is preferably 1 to 80 mass %, more preferably 5 to 60 mass %, and even more preferably 10 to 40 mass %, relative to 100 mass % of all structural units of polymer X.

[0119] The content of the structural unit (F') is preferably 1 to 80 mass %, more preferably 5 to 60 mass %, and even more preferably 10 to 40 mass %, relative to 100 mass % of all structural units of polymer X.

[0120] The preferred carboxylic acid value, phenolic hydroxyl group acid value, weight average molecular weight, and polymerizable double bond equivalent of the polymer X are the same as the respective numerical ranges of the polymers described above.

[0121] The method for producing the polymer X is not particularly limited, but preferably includes a similar production method to the above-mentioned production method for the polymer, except that the above-mentioned monomer (c) is not used in step (1) of the production method for the polymer.

[0122] 4. Curable Resin Composition The present invention also relates to a curable resin composition comprising the above-described polymer (including the above-described polymerizable X) and a polymerization initiator. The curable resin composition of the present invention contains the above-described polymer, and therefore can provide a cured product that has excellent developability, heat resistance, and adhesion. Furthermore, by including a polymerization initiator, the curability is improved, and a cured product with even more excellent heat resistance and adhesion can be provided.

[0123] The content of the polymer is preferably 1 to 90 mass%, more preferably 5 to 50 mass%, and even more preferably 10 to 40 mass%, relative to 100 mass% of the total solid content of the curable resin composition. In this specification, the term "total solid content" refers to the total amount of components that form a cured product (components excluding solvents and the like that volatilize during the formation of a cured product and curing catalysts).

[0124] (Polymerization initiator) Examples of the polymerization initiator include a photopolymerization initiator and a thermal polymerization initiator. These may be selected appropriately depending on the components contained in the curable resin composition. For example, when the curable resin composition is used as a photosensitive resin composition that enables fine processing or image formation of a cured product by photolithography, a photopolymerization initiator may be added to the composition for photocuring. Thus, the curable resin composition is preferably a photosensitive resin composition containing the above-mentioned polymer and a photopolymerization initiator.

[0125] Examples of the photopolymerization initiator include aminoketone compounds such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one ("IRGACURE907", manufactured by BASF), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1-one ("IRGACURE369", manufactured by BASF), and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one ("IRGACURE379", manufactured by BASF); 2,2-dimethoxy-1,2-diphenylethan-1-one ("IRGACURE651", manufactured by BASF), and phenylglyoxylic acid methyl ester ("DAROCURE benzyl ketal compounds such as 1-hydroxy-cyclohexyl-phenyl-ketone ("IRGACURE184", manufactured by BASF), 2-hydroxy-2-methyl-1-phenyl-propan-1-one ("DAROCUR1173", manufactured by BASF), 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one ("IRGACURE2959", manufactured by BASF), 2-hydroxy -1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one ("IRGACURE 127", manufactured by BASF Corporation), [1-hydroxy-cyclohexyl-phenyl-ketone + benzophenone] ("IRGACURE 500", manufactured by BASF Corporation), and other hydroketone compounds; as well as other alkylphenone compounds exemplified in paragraphs

[0084] to

[0086] of JP-A No. 2013-227485;1,2-Octanedione, 1-[4-(phenylthio)phenyl]-, 2-(O-benzoyloxime) ("OXE01", manufactured by BASF), ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime) ("OXE02", manufactured by BASF), 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)], ethanone ("OXE03", manufactured by BASF), 1-[9-ethyl -6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(O-acetyloxime) ("OXE04", manufactured by BASF), and other oxime ester compounds; benzophenone compounds; benzoin compounds; thioxanthone compounds; halomethylated triazine compounds; halomethylated oxadiazole compounds; biimidazole compounds; titanocene compounds; benzoic acid ester compounds; acridine compounds; and phosphine oxide compounds.

[0126] The curable resin composition may contain one or more polymerization initiators. The content of the polymerization initiator(s) is preferably 0.5 to 30% by mass, more preferably 1 to 20% by mass, and even more preferably 3 to 10% by mass, relative to 100% by mass of the total solid content of the curable resin composition.

[0127] (Polymerizable Compound) The curable resin composition may further contain a polymerizable compound. The polymerizable compound is a low-molecular compound having a polymerizable unsaturated bond (also referred to as a polymerizable unsaturated group) that can be polymerized by irradiation with active energy rays such as free radicals, electromagnetic waves (e.g., infrared rays, ultraviolet rays, X-rays, etc.), and electron beams. Examples of the polymerizable compound include monofunctional compounds having one polymerizable unsaturated group in the molecule and polyfunctional compounds having two or more polymerizable unsaturated groups.

[0128] Examples of the monofunctional compound include N-substituted maleimide monomers, (meth)acrylic acid esters, (meth)acrylamides, unsaturated monocarboxylic acids, unsaturated polycarboxylic acids, unsaturated monocarboxylic acids in which the unsaturated group and the carboxyl group are chain-extended, unsaturated acid anhydrides, aromatic vinyls, conjugated dienes, vinyl esters, vinyl ethers, N-vinyl compounds, unsaturated isocyanates, etc. Furthermore, monomers having an active methylene group or an active methine group can also be used.

[0129] Examples of the polyfunctional compound include the following compounds: bifunctional (meth)acrylate compounds such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, hexanediol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, bisphenol A alkylene oxide di(meth)acrylate, and bisphenol F alkylene oxide di(meth)acrylate;

[0130] Trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, ethylene oxide-added trimethylolpropane tri(meth)acrylate, ethylene oxide-added ditrimethylolpropane tetra(meth)acrylate, ethylene oxide-added pentaerythritol tetra(meth)acrylate, ethylene oxide-added dipentaerythritol hexa(meth)acrylate, propylene oxide-added trimethylolpropane tri(meth)acrylate, propylene oxide-added ditrimethylolpropane tetra(meth)acrylate, propylene oxide-added pentaerythritol tetra(meth)acrylate, propylene oxide-added dipentaerythritol hexa(meth)acrylate, ε-caprolactone-added trimethylolpropane tri(meth)acrylate, ε-caprolactone-added ditrimethylolpropane tetra(meth)acrylate, ε-caprolactone-added pentaerythritol tetra(meth)acrylate, ε-caprolactone-added dipentaerythritol hexa(meth)acrylate, dipentaerythritol pentaacrylate succinic acid-modified product, pentaerythritol triacrylate succinic acid-modified product, dipentaerythritol pentaacrylate phthalic acid-modified product, pentaerythritol triacrylate phthalic acid-modified product,

[0131]

[0132] polyfunctional (meth)acrylate compounds having three or more functional groups, such as modified dipentaerythritol hexaacrylate represented by the formula: polyfunctional vinyl ethers such as ethylene glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butylene glycol divinyl ether, hexanediol divinyl ether, bisphenol A alkylene oxide divinyl ether, bisphenol F alkylene oxide divinyl ether, trimethylolpropane trivinyl ether, ditrimethylolpropane tetravinyl ether, glycerin trivinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether, ethylene oxide-added trimethylolpropane trivinyl ether, ethylene oxide-added ditrimethylolpropane tetravinyl ether, ethylene oxide-added pentaerythritol tetravinyl ether, and ethylene oxide-added dipentaerythritol hexavinyl ether;

[0133] vinyl ether group-containing (meth)acrylic acid esters such as 2-vinyloxyethyl (meth)acrylate, 3-vinyloxypropyl (meth)acrylate, 1-methyl-2-vinyloxyethyl (meth)acrylate, 2-vinyloxypropyl (meth)acrylate, 4-vinyloxybutyl (meth)acrylate, 4-vinyloxycyclohexyl (meth)acrylate, 5-vinyloxypentyl (meth)acrylate, 6-vinyloxyhexyl (meth)acrylate, 4-vinyloxymethylcyclohexylmethyl (meth)acrylate, p-vinyloxymethylphenylmethyl (meth)acrylate, 2-(vinyloxyethoxy)ethyl (meth)acrylate, and 2-(vinyloxyethoxyethoxyethoxy)ethyl (meth)acrylate;

[0134] polyfunctional allyl ethers such as ethylene glycol diallyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether, propylene glycol diallyl ether, butylene glycol diallyl ether, hexanediol diallyl ether, bisphenol A alkylene oxide diallyl ether, bisphenol F alkylene oxide diallyl ether, trimethylolpropane triallyl ether, ditrimethylolpropane tetraallyl ether, glycerin triallyl ether, pentaerythritol tetraallyl ether, dipentaerythritol pentaallyl ether, dipentaerythritol hexaallyl ether, ethylene oxide-added trimethylolpropane triallyl ether, ethylene oxide-added ditrimethylolpropane tetraallyl ether, ethylene oxide-added pentaerythritol tetraallyl ether, and ethylene oxide-added dipentaerythritol hexaallyl ether;

[0135] Allyl group-containing (meth)acrylic acid esters such as allyl (meth)acrylate; polyfunctional (meth)acryloyl group-containing isocyanurates such as tri(acryloyloxyethyl)isocyanurate, tri(methacryloyloxyethyl)isocyanurate, alkylene oxide-added tri(acryloyloxyethyl)isocyanurate, and alkylene oxide-added tri(methacryloyloxyethyl)isocyanurate; polyfunctional allyl group-containing isocyanurates such as triallyl isocyanurate; polyfunctional urethane (meth)acrylates obtained by reacting polyfunctional isocyanates such as tolylene diisocyanate, isophorone diisocyanate, and xylylene diisocyanate with hydroxyl group-containing (meth)acrylic acid esters such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate; polyfunctional aromatic vinyls such as divinylbenzene; etc. These polymerizable compounds may be used alone or in combination of two or more.

[0136] Among the polymerizable compounds, it is preferable to use a polyfunctional polymerizable compound from the viewpoint of further enhancing the curability of the curable resin composition. The number of functions of the polyfunctional polymerizable compound is preferably 3 or more, more preferably 4 or more. The number of functions is preferably 10 or less, more preferably 8 or less. The molecular weight of the polymerizable compound is not particularly limited, but is preferably, for example, 2000 or less from the viewpoint of handling.

[0137] As the polyfunctional polymerizable compound, from the viewpoints of reactivity, economy, availability, etc., preferred are compounds having a (meth)acryloyl group, such as polyfunctional (meth)acrylate compounds, polyfunctional urethane (meth)acrylate compounds, and (meth)acryloyl group-containing isocyanurate compounds, and more preferred are polyfunctional (meth)acrylate compounds. By including a compound having a (meth)acryloyl group, the curable resin composition has better photosensitivity and curability, and a cured product with even higher hardness and transparency can be obtained. It is more preferred to use a trifunctional or higher polyfunctional (meth)acrylate compound as the polyfunctional polymerizable compound.

[0138] The content of the polymerizable compound is preferably 1 to 80 mass%, more preferably 10 to 50 mass%, and even more preferably 20 to 40 mass%, relative to 100 mass% of the total solid content of the curable resin composition.

[0139] The curable resin composition may further contain other components in addition to the above-mentioned components, as necessary. Examples of the other components include photoacid generators; photobase generators; thermal acid generators; solvents; colorants (pigments, dyes); dispersants; heat resistance improvers; leveling agents; development aids; silane-based, aluminum-based, titanium-based, and other coupling agents; fillers, thermosetting resins such as phenolic resins, polyvinylphenols, epoxy compounds, and epoxy resins; plasticizers; polymerization inhibitors; ultraviolet absorbers; antioxidants; matting agents; defoaming agents; antistatic agents; slip agents; surface modifiers; thixotropic agents; thixotropic aids; quinone diazide compounds; polyhydric phenol compounds; and cationically polymerizable compounds. These may be used alone or in combination of two or more. These other components can be appropriately selected from known compounds and used, and the amount used can also be appropriately determined.

[0140] The method for preparing the curable resin composition is not particularly limited and may be a known method, for example, a method in which the above-mentioned components are mixed and dispersed using various mixers or dispersers. The mixing and dispersion step is not particularly limited and may be performed by a known method. In addition, other steps that are usually performed may be further included.

[0141] The method for curing the curable resin composition to obtain a cured product is not particularly limited, and any known method may be used. For example, the curable resin composition may be applied or molded onto a substrate, and then cured by heating, irradiating with active energy rays such as ultraviolet rays, or a combination of these to obtain a cured product.

[0142] When the curable resin composition is used as a photosensitive resin composition, for example, the curable resin composition is applied to a substrate by a known method, and dried as necessary to form a coating film, and the coating film is exposed to light through a photomask. After exposure, the unexposed portion is dissolved in an alkaline aqueous solution to perform alkaline development, and then heated (post-cured) to obtain a cured product. The application, drying, exposure, alkaline development, and heating can each be performed by a known method, such as the method described in JP 2014-148610 A.

[0143] When the cured product is a cured film, the film thickness of the cured film may be appropriately set depending on the purpose and application, but from the viewpoint of exhibiting good heat resistance and adhesion, it is preferably 0.1 to 100 μm, more preferably 1 to 20 μm, and even more preferably 2 to 10 μm.

[0144] The polymer and curable resin composition of the present invention can provide a cured product having excellent developability, heat resistance, and adhesion. Therefore, the polymer and curable resin composition of the present invention can be suitably used in applications requiring developability, heat resistance, or adhesion.

[0145] The polymers and curable resin compositions are preferably used in applications such as various optical components and electrical / electronic devices, including color filters, black matrices, photospacers, black column spacers, inks, printing plates, printed wiring boards, semiconductor elements, photoresists, insulating films, films, organic protective films, interlayer insulating films, and interlayer insulating films for rewiring layers, which are used in liquid crystal, organic EL, quantum dot, and micro LED liquid crystal displays, solid-state imaging devices, and touch panel display devices.

[0146] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass."

[0147] In the examples, various physical properties were measured as follows. <Polymerizable double bond equivalent (g / equivalent)> This was determined by dividing the mass (g) of the solid content of the polymer solution by the amount of double bonds (mol) of the polymer. The amount of double bonds was determined by dividing the mass of the compound having a polymerizable double bond that reacted during the introduction of the polymerizable double bond by the molecular weight.

[0148] <Weight Average Molecular Weight> The weight average molecular weight was measured by GPC (gel permeation chromatography) using polystyrene as a standard substance and tetrahydrofuran as an eluent, using HLC-8220GPC (manufactured by Tosoh Corporation) (column TSKgel SuperHZ).

[0149] <Carboxylic Acid Value (mg KOH / g)> Approximately 3 g of each polymer solution was weighed out and dissolved in a mixed solvent of 90 g of acetone and 10 g of water. The solution was titrated using a 0.1 N aqueous solution of KOH as a titrant. The titration was performed using an automatic titrator (product name: COM-555, manufactured by Hiranuma Sangyo Co., Ltd.), and the acid value per 1 g of solids (mg KOH / g) was determined from the acid value of the polymer solution and the solids content of the polymer solution. The solids content of the polymer solution was determined as follows. That is, approximately 1 g of the polymer solution was weighed out in an aluminum cup, dissolved by adding approximately 3 g of acetone, and then allowed to dry naturally at room temperature. The solution was then dried at 160°C for 1.5 hours using a vacuum dryer (manufactured by EYELA, product name: VOS-301SD), allowed to cool in a desiccator, and its mass was measured. The solids content (% by mass) of the polymer solution was calculated from the mass loss.

[0150] <Phenol Hydroxyl Group Acid Value (mg KOH / g)> Approximately 3 g of each polymer solution was weighed out and dissolved in a mixed solvent of 90 g of toluene and 10 g of ethanol. A 0.5 N KOH-ethanol solution was used as the titrant. The titration was performed using an automatic titrator (product name: COM-555, manufactured by Hiranuma Sangyo Co., Ltd.). The total acid value (mg KOH / g) derived from phenolic hydroxyl groups and carboxylic acids per 1 g of solids was determined from the acid value of the polymer solution and the solid content of the polymer solution. From the resulting total acid value, the total acid equivalent (mmol) (referred to as X) per 1 g of solids derived from carboxylic acids and phenolic hydroxyl groups was calculated. Similarly, the total acid equivalent (mmol) (referred to as Y) per 1 g of solids derived from carboxylic acids was calculated from the carboxylic acid acid value. The acid value (mg KOH / g) of phenolic hydroxyl groups per 1 g of solids was then calculated by multiplying (X-Y) by 56.11. The solid content of the polymer solution was determined by the following method. That is, about 1 g of the polymer solution was precisely weighed into an aluminum cup, and about 3 g of acetone was added to dissolve the polymer solution, followed by air drying at room temperature. The solution was then dried at 160°C for 1.5 hours using a vacuum dryer (EYELA, product name: VOS-301SD), and then allowed to cool in a desiccator, after which the mass was measured. The solid content (% by mass) of the polymer solution was calculated from the mass loss.

[0151] <Glycidyl methacrylate (GMA) reaction rate (%)> Sampling was performed for each polymerization solution during the GMA addition reaction step, and the amount of GMA in the polymerization solution was measured using gas chromatography (product name: GC-2014, manufactured by Shimadzu Corporation) to determine the GMA residual rate (%). The GMA reaction rate (%) was calculated using the initial GMA content (%) and the GMA residual rate (%) during the reaction.

[0152] <5% Weight Loss Temperature (°C)> A solution prepared by adding 4 g of tetrahydrofuran to 2 g of each polymer solution was added dropwise to 60 g of hexane, and the precipitated polymer was separated, removed, and vacuum dried overnight at 40°C. 10 mg of the obtained polymer powder was weighed, and the temperature at which the weight decreased by 5% under a nitrogen atmosphere was measured using a thermogravimetric analyzer TGA-50 (manufactured by Shimadzu Corporation). The higher the 5% weight loss temperature, the better the thermal decomposition resistance.

[0153] <Development Time> A solution obtained by diluting each polymer solution with propylene glycol monomethyl ether acetate (PGMEA) so that the resin solid content was 30% relative to the solid content of the polymer solution was spin-coated onto a glass plate (50 mm long x 50 mm wide), dried at 90°C for 3 minutes, and then cooled to room temperature to prepare a test plate for evaluation on which a coating film with a thickness of 4 μm was formed. The prepared test plate was immersed and shaken in a 2.38% by mass aqueous solution of tetramethylammonium hydroxide, and the degree of dissolved residue was visually observed to evaluate the development time (seconds). If the development time is short, the development margin cannot be secured, narrowing the development tolerance range when evaluating compositions, etc. The development time is preferably between 20 and 180 seconds, more preferably between 60 and 180 seconds.

[0154] <Minimum Adhesion Pattern (μm)> A curable resin composition was applied to a 10 cm square glass substrate by spin coating, and the substrate was subjected to heat treatment (90°C, 3 minutes). After that, the substrate was irradiated with 60 mJ / cm 2 of light using a UV aligner (manufactured by Dai Nippon Kaken Co., Ltd., product name "MA-1100") equipped with a 2.0 kW ultra-high pressure mercury lamp through a photomask having 30 μm line-and-space openings at a distance of 50 μm from the coating film. ２The film was exposed to an exposure dose of 1000 kJ / cm² (equivalent to a 365 nm illuminance), and a 2.38% aqueous solution of tetramethylammonium hydroxide was sprayed using a spin developer to dissolve and remove the unexposed areas. The remaining exposed areas were then washed with pure water for 10 seconds to obtain a coating film. The coating film developed through the photomask as described above was observed using a surface roughness meter (manufactured by Ryoka Systems Co., Ltd., product name "VertScan 2.0"), and the size of the smallest pattern was taken as the minimum adhesion pattern. The closer the minimum adhesion pattern was to 1, the better the adhesion was judged to be.

[0155] <Dielectric loss tangent> Acetone was added to 30 g of the polymer solution to prepare 300 g of diluted polymer solution, and the diluted polymer solution was added dropwise to hexane with stirring to reprecipitate the polymer, which was then heated to 130 to 180°C to melt it, and a rod-shaped polymer sample having a diameter of 1 to 2.5 mm was obtained using a melt indexer. The dielectric loss tangent of the obtained polymer sample was measured using a network analyzer E8361A (manufactured by Agilent Technologies) by the cavity resonator perturbation method under conditions of a temperature of 25°C, humidity of 50%, and a frequency of 10 GHz.

[0156] Synthesis Example 1 (Example 1) 100 g of propylene glycol monomethyl ether acetate (PGMEA) was charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 57.6 g of N-benzylmaleimide, 30.0 g of methacrylic acid, and 150 g of PGMEA were mixed in dropping vessel 1. 15.6 g of cyclohexyl methacrylate, 16.8 g of p-isopropenylphenol, and 36.0 g of PGMEA were mixed in dropping vessel 2. 8.4 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 30.0 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the mixture was added dropwise from dropping vessels 1, 2, and 3 to the reaction vessel at a constant rate over 4.0 hours. After the dropwise addition was completed, the mixture was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 19.8 g of glycidyl methacrylate, 0.4 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%), to obtain a polymer solution (A-1). The property values ​​of the obtained polymer are shown in Table 1.

[0157] Synthesis Example 2 (Example 2) 135 g of propylene glycol monomethyl ether acetate (PGMEA) and 31 g of carbitol acetate were charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the vessel was heated to 90°C. Meanwhile, 10.0 g of N-phenylmaleimide, 30.0 g of methacrylic acid, 30.0 g of 4-hydroxyphenyl methacrylate, and 63 g of PGMEA were mixed in dropping vessel 1. Furthermore, 30.0 g of cyclohexyl methacrylate, 2.0 g of 3-mercaptopropionic acid, and 36.0 g of carbitol acetate were mixed in dropping vessel 2. 5.0 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 20.0 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90 ° C, the mixture was added dropwise from dropping tanks 1, 2, and 3 to the reaction tank at a constant rate over 4.0 hours. After completion of the addition, the mixture was maintained at 90 ° C for 30 minutes, then the reaction temperature was raised to 115 ° C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 24.8 g of glycidyl methacrylate, 0.4 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115 ° C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%) to obtain a polymer solution (A-2). The property values ​​of the obtained polymer are shown in Table 1.

[0158] Synthesis Example 3 (Example 3) 155 g of propylene glycol monomethyl ether acetate (PGMEA) was charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 40.0 g of N-phenylmaleimide, 20.0 g of methacrylic acid, 73.3 g of 4-hydroxyphenyl methacrylate, and 200 g of PGMEA were mixed in dropping vessel 1. Furthermore, 9.3 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 22 g of PGMEA were mixed in dropping vessel 2. While maintaining the reaction temperature at 90°C, the mixture was added dropwise from dropping vessels 1 and 2 to the reaction vessel at a constant rate over 4.0 hours. After completion of the dropwise addition, the mixture was maintained at 90°C for 30 minutes, and then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 30.4 g of Cyclomer M100 (3,4-epoxycyclohexylmethyl methacrylate, manufactured by Daicel Chemical Industries, Ltd.), 0.5 g of triphenylphosphine as a reaction catalyst, and 0.3 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%) to obtain a polymer solution (A-3). The property values ​​of the obtained polymer are shown in Table 1.

[0159] Synthesis Example 4 (Example 4) 140 g of propylene glycol monomethyl ether acetate (PGMEA) and 40 g of isopropanol were charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the vessel was heated to 90°C. Meanwhile, 43.8 g of N-phenylmaleimide, 25.0 g of methacrylic acid, 37.5 g of 4-hydroxyphenyl methacrylate, and 108 g of PGMEA were mixed in dropping vessel 1. 18.8 g of styrene and 44 g of isopropanol were mixed in dropping vessel 2. 12.5 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 29.0 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the contents were added dropwise from dropping vessels 1, 2, and 3 to the reaction vessel at a constant rate over 4.0 hours. After the dropwise addition was completed, the mixture was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 31.0 g of glycidyl methacrylate, 0.5 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%) to obtain a polymer solution (A-4). The property values ​​of the obtained polymer are shown in Tables 1 and 3.

[0160] Synthesis Example 5 (Example 5) 116 g of propylene glycol monomethyl ether acetate (PGMEA) and 39 g of isopropanol were charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the vessel was heated to 90°C. Meanwhile, 42.0 g of N-phenylmaleimide, 18.0 g of methacrylic acid, 36.0 g of 4-hydroxyphenyl methacrylate, 18.0 g of 2-hydroxyethyl methacrylate, and 123 g of PGMEA were mixed in dropping vessel 1. 6.0 g of styrene and 43 g of isopropanol were mixed in dropping vessel 2. 16.8 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 39.2 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the contents were added dropwise to the reaction vessel from dropping vessels 1, 2, and 3 at a constant rate over 4.0 hours. After the dropwise addition was completed, the mixture was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 23.8 g of glycidyl methacrylate, 0.4 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%), to obtain a polymer solution (A-5). The property values ​​of the obtained polymer are shown in Table 1.

[0161] Synthesis Example 6 (Example 6) 127 g of propylene glycol monomethyl ether acetate (PGMEA) and 30 g of isopropanol were charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 35.0 g of N-phenylmaleimide, 10.0 g of methacrylic acid, 35.0 g of 4-hydroxystyrene, and 70 g of PGMEA were mixed in dropping vessel 1. 20.0 g of styrene and 37 g of isopropanol were mixed in dropping vessel 2. 2.00 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 10.0 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the mixture was added dropwise from dropping vessels 1, 2, and 3 to the reaction vessel at a constant rate over 4.0 hours. After the dropwise addition was completed, the mixture was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 7.4 g of glycidyl methacrylate, 0.3 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%), to obtain a polymer solution (A-6). The property values ​​of the obtained polymer are shown in Table 1.

[0162] Synthesis Example 7 (Example 7) 126 g of propylene glycol monomethyl ether acetate (PGMEA) and 42 g of isopropanol were charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 45.5 g of N-phenylmaleimide, 6.5 g of methacrylic acid, 39.0 g of 4-hydroxyphenyl methacrylate, 32.5 g of 2-hydroxyethyl methacrylate, and 133 g of PGMEA were mixed in dropping vessel 1. 6.5 g of styrene and 46.3 g of isopropanol were mixed in dropping vessel 2. 7.8 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 18 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the mixture was added dropwise to the reaction vessel from dropping vessels 1, 2, and 3 at a constant rate over 4.0 hours. After the dropwise addition was completed, the mixture was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 23.3 g of Karenz MOI (2-methacryloyloxyethyl isocyanate, manufactured by Resonac Corporation), 0.5 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%) to obtain a polymer solution (A-7). The property values ​​of the obtained polymer are shown in Table 1.

[0163] Synthesis Example 8 (Comparative Example 1) 166 g of propylene glycol monomethyl ether acetate (PGMEA) and 46 g of isopropanol were charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 20.0 g of methacrylic acid, 30.0 g of 4-hydroxyphenyl methacrylate, and 32 g of PGMEA were mixed in dropping vessel 1. Furthermore, 50.0 g of cyclohexyl methacrylate and 22.0 g of isopropanol were mixed in dropping vessel 2. 9.0 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 21.0 g of PGMEA were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the mixture was added dropwise from dropping vessels 1, 2, and 3 to the reaction vessel at a constant rate over 4.0 hours. After the dropwise addition was completed, the mixture was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 24.8 g of glycidyl methacrylate, 0.4 g of triphenylphosphine as a reaction catalyst, and 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor were added, and the mixture was reacted at 115°C for 13 hours while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%) to obtain a polymer solution (B-1). The property values ​​of the obtained polymer are shown in Tables 1 and 3.

[0164] Synthesis Example 9 (Comparative Example 2) A polymer solution (B-2) was obtained by the same procedure as in Synthesis Example 8, except that 30.0 g of N-phenylmaleimide was used instead of 30.0 g of 4-hydroxyphenyl methacrylate, and the amounts of methacrylic acid and cyclohexyl methacrylate were changed to 30.0 g and 40.0 g, respectively. The property values ​​of the obtained polymer are shown in Table 1.

[0165] Synthesis Example 10 (Comparative Example 3) A polymer solution (B-3) was obtained by the same procedure as in Synthesis Example 8, except that 30.0 g of N-phenylmaleimide was used instead of 20.0 g of methacrylic acid, the amounts of 4-hydroxyphenyl methacrylate, cyclohexyl methacrylate, and glycidyl methacrylate were changed to 35.0 g, 35.0 g, and 12.0 g, respectively, and the addition reaction step was performed for 14 hours. The property values ​​of the obtained polymer are shown in Table 1.

[0166] Synthesis Example 11 (Comparative Example 4) 200 g of carbitol acetate was charged into a separable flask equipped with a condenser as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 36.0 g of N-benzylmaleimide, 6.0 g of methacrylic acid, 36.0 g of 4-hydroxyphenyl methacrylate, and 66 g of carbitol acetate were mixed in dropping vessel 1. 42.0 g of cyclohexyl methacrylate and 53.0 g of carbitol acetate were mixed in dropping vessel 2. 10.8 g of t-butylperoxy-2-ethylhexanoate as a polymerization initiator and 25.2 g of carbitol acetate were mixed in dropping vessel 3. While maintaining the reaction temperature at 90°C, the contents were added dropwise from dropping vessels 1, 2, and 3 to the reaction vessel at a constant rate over 4.0 hours. After the dropwise addition, the temperature was maintained at 90°C for 30 minutes, then the reaction temperature was raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, a polymer solution (B-4) was obtained. The property values ​​of the obtained polymer are shown in Table 1.

[0167] FIG. 1 is a graph showing the change over time in the reaction rate of glycidyl methacrylate (GMA) with respect to the base polymer during the synthesis of the polymers of Example 3 and Comparative Example 3.

[0168] (Examples 8 to 14, Comparative Examples 5 to 8) The polymer solution obtained above was mixed with dipentaerythritol hexaacrylate, a photopolymerization initiator (Irgacure OXE-02, manufactured by BASF), and propylene glycol monomethyl ether acetate in the formulation (solid content) shown in Table 2 to obtain curable resin compositions 1 to 11. The obtained curable resin compositions 1 to 11 were evaluated for adhesion (minimum adhesion pattern). The results are shown in Table 2.

[0169] Example 15, Comparative Example 9 The dielectric loss tangents of the polymer solutions (A-4) and (B-1) were evaluated by the method described above. The results are shown in Table 3.

[0170]

[0171]

[0172]

[0173] Tables 1 and 2 confirm that the polymers of the examples, which essentially contain a structural unit having a carboxylic acid group, a structural unit having a phenolic hydroxyl group, a structural unit having a ring structure in the main chain, and a structural unit having a polymerizable unsaturated group, are excellent in all of thermal decomposition resistance, adhesion, and developability. Furthermore, Table 3 confirms that the polymers of the examples, which contain a structural unit having a ring structure in the main chain, have a lower dielectric tangent due to their rigid skeleton and are excellent in electrical properties compared to polymers which do not contain such structural units.

[0174] Furthermore, as shown in Figure 1, it was confirmed that a polymer having a structural unit having a carboxylic group has higher reactivity with glycidyl methacrylate and is superior in synthesis efficiency compared to a polymer not having such a structural unit.

[0175] Furthermore, among the polymers of the examples, polymers (A-3) to (A-7) having a carboxylic acid acid value of 1 to 40 mgKOH / g and a phenolic hydroxyl group acid value of 40 to 200 mgKOH / g showed superior adhesion and developability. Furthermore, polymers (A-4) to (A-7) having structural units derived from aromatic monomers without ester bonds (excluding the structural units having a phenolic hydroxyl group) showed superior thermal decomposition resistance and adhesion. In particular, polymers (A-4) to (A-6) using a component selected from monomers having an aziridine group, an oxazoline group, or an epoxy group when introducing a double bond showed better thermal decomposition resistance than polymer (A-7) using a monomer component having an isocyanate group.

[0176] On the other hand, the comparative polymers (B-1) to (B-4) that did not satisfy at least one of the above conditions were inferior in thermal decomposition resistance, adhesion, and developability. The polymer (B-1) that did not have a structural unit having a ring structure in the main chain resulted in low thermal decomposition resistance. The polymer (B-2) that did not have a structural unit having a phenolic hydroxyl group resulted in poor adhesion and developability due to the lack of an aromatic ring, which prevented the π-π stacking effect, and insufficient alkali solubility. The polymer (B-3) that did not have a structural unit having an unsaturated carboxylic acid also resulted in poor developability and pattern formation, due to insufficient alkali solubility. The polymer (B-4) that did not have a structural unit having a polymerizable unsaturated group was thought to have reduced adhesion due to insufficient photocurability upon exposure.

[0177] The polymer of the present invention and the curable resin composition containing the polymer have excellent adhesion and developability, and therefore can be suitably used as a resist polymer or a photosensitive resin composition. In addition, the polymer has excellent heat resistance, and therefore can be suitably used as an interlayer insulating film material, etc.

Claims

1. A polymer characterized by having a structural unit (A) having a carboxylic acid group, a structural unit (B) having a phenolic hydroxyl group, a structural unit (C) having a ring structure in the main chain, and a structural unit (D) having a polymerizable unsaturated group.

2. The polymer according to claim 1, wherein the structural unit (D) does not have a urethane bond.

3. The polymer according to claim 1 or 2, characterized in that the acid value of the carboxylic acid is 1 to 40 mgKOH / g and the acid value of the phenolic hydroxyl group is 40 to 200 mgKOH / g.

4. The polymer according to any one of claims 1 to 3, characterized in that the polymer comprises a structural unit (E) derived from an aromatic monomer (excluding the structural unit (B) having a phenolic hydroxyl group).

5. A polymer described in any one of claims 1 to 4, characterized in that the content of the structural unit (C) having a ring structure in the main chain is 5 to 60 mass % relative to 100 mass % of all structural units of the polymer.

6. The polymer according to any one of claims 1 to 5, wherein the structural unit (C) having a ring structure in the main chain is a structural unit derived from a maleimide monomer.

7. A curable resin composition comprising the polymer according to any one of claims 1 to 6 and a polymerization initiator.

8. A method for producing a polymer, comprising: a step (1) of polymerizing monomer components including an unsaturated carboxylic acid monomer (a), a monomer (b) having a phenolic hydroxyl group, and a monomer (c) that introduces a ring structure into the main chain; and a step (2) of reacting the polymer obtained in step (1) with a compound (d) having a group reactive with a carboxyl group and / or a phenolic hydroxyl group and a polymerizable unsaturated group, thereby introducing a polymerizable unsaturated group into the side chain of the polymer.

9. The method for producing a polymer according to claim 8, wherein the polymer has a carboxylic acid value of 1 to 40 mg KOH / g and a phenolic hydroxyl group acid value of 40 to 200 mg KOH / g.

10. The method for producing a polymer according to claim 8 or 9, characterized in that step (2) is carried out in the presence of a tertiary phosphine.

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