Copolymer, photosensitive resin composition, material for pattern formation, cured product, and image display device

Abstract

A copolymer containing a repeating structural unit A1 represented by general formula (1) and a repeating structural unit A2 represented by general formula (2). (In formula (1) and formula (2), R1 is hydrogen or methyl, A1 is a chemical structure having an alkoxysilyl group at a terminal, and A2 is a chemical structure having a group other than an alkoxysilyl group at a terminal that generates a hydroxyl group by acid dissociation)

Description

Technical Field

[0001] This invention relates to copolymers, photosensitive resin compositions, pattern forming materials, cured products, and image display devices. This application claims priority to Japanese Patent Application No. 2023-177122, filed October 12, 2023, and incorporates all the contents described in that Japanese patent application. Background Technology

[0002] Photolithography is a microfabrication technique used for forming circuit patterns in large-scale integrated circuits (LSI) and for forming spacers disposed between substrates constituting liquid crystal displays. Many solutions have been proposed for the photosensitive resin compositions used in photolithography. Patent Document 1 discloses a negative photosensitive resin composition containing an alkali-soluble resin, a photoradical polymerization initiator, and a photopolymerizable monomer, wherein the photopolymerizable monomer includes a photopolymerizable monomer having an isocyanuric acid backbone and a photopolymerizable monomer having a fluorene backbone.

[0003] Patent Document 2 discloses a photosensitive resin composition used as a spacer forming material. The photosensitive resin composition described in Patent Document 2 comprises an adhesive polymer, a photopolymerizable compound, a photopolymerization initiator, and a thiol-containing hydrogen donor, wherein the photopolymerizable compound comprises a photopolymerizable compound having an olefinic unsaturated group and an isocyanurate ring structure.

[0004] Patent Document 3 discloses a photosensitive resin composition comprising an alkali-soluble resin, a crosslinking agent, a photopolymerization initiator, and an acid catalyst. The alkali-soluble resin in the photosensitive resin composition disclosed in Patent Document 3 is a (meth)acrylate copolymer containing repeating structural units with a side chain length of a certain length and a carboxyl group at the end of the side chain.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-124929

[0008] Patent Document 2: International Publication No. 2013 / 115262

[0009] Patent Document 3: International Publication No. 2023 / 090286 Summary of the Invention

[0010] In brief, the photolithography process involves coating a photosensitive resin composition → (pre-baking) → exposure → development → (post-baking). Considering the heat resistance of the product to which photolithography is performed, it is desirable to perform the photolithography process at low temperatures (e.g., below 150°C). Furthermore, it is preferable that the hardness of the cured material formed even at such temperatures is high. Moreover, it is desirable to form patterns with fine linewidths and through-holes with small opening diameters through photolithography.

[0011] In view of this situation, one of the objects of the present invention is to provide a photosensitive resin composition that forms a hard cured material even when photolithography is performed at low temperatures and has excellent patternability (photolithography), as well as a copolymer constituting the photosensitive resin composition.

[0012] A copolymer comprising repeating structural unit A1 as shown in general formula (1) and repeating structural unit A2 as shown in general formula (2).

[0013]

[0014]

[0015] (In equations (1) and (2), R) 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 (This refers to a chemical structure with a terminal group other than an alkoxysilyl group that generates a hydroxyl group through acid dissociation.)

[0016] A photosensitive resin composition comprising:

[0017] Polymers comprising at least the repeating structural unit A1 shown in general formula (1) below,

[0018] Polymers comprising at least the repeating structural unit A2 shown in general formula (2) below, and

[0019] Photoacid generator (B).

[0020]

[0021]

[0022] (In equations (1) and (2), R) 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 (This refers to a chemical structure with a terminal group other than an alkoxysilyl group that generates a hydroxyl group through acid dissociation.)

[0023] Based on the above copolymer, a photosensitive resin composition can be provided that forms a cured product with high hardness even when photolithography is performed at low temperatures and has excellent patterning properties (photolithography). Furthermore, based on the above photosensitive resin composition, a photosensitive resin composition can be provided that forms a cured product with high hardness even when photolithography is performed at low temperatures and has excellent patterning properties (photolithography). Detailed Implementation

[0024] [Summary of Implementation Methods]

[0025] First, embodiments of the copolymers, photosensitive resin compositions, pattern forming materials, cured products, and image display devices disclosed herein will be described. It should be noted that, unless otherwise specified, "A to B" in this specification means "A or more and B or less" when indicating a numerical range.

[0026] The copolymer disclosed herein is a copolymer comprising repeating structural unit A1 as shown in general formula (1) and repeating structural unit A2 as shown in general formula (2).

[0027]

[0028]

[0029] (In equations (1) and (2), R) 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 (This refers to a chemical structure with a terminal group other than an alkoxysilyl group that generates a hydroxyl group through acid dissociation.)

[0030] The copolymer disclosed herein is a copolymer comprising repeating structural unit A1 as shown in general formula (1) above and repeating structural unit A2 as shown in general formula (2) below. Structural unit A1 is a structural unit with an alkoxysilyl group at the end. Structural unit A2 is a structural unit with a group other than alkoxysilyl group at the end that generates a hydroxyl group upon acid dissociation. In other words, structural unit A2 is a structural unit with a protecting group at the end that is acid-dissociable and generates a hydroxyl group upon deprotection. Although not limited by a specific theory, it is believed that in the photolithography exposure process of the copolymer disclosed herein, the hydroxyl group generated by the deprotection of structural unit A2 reacts with the alkoxysilyl group of structural unit A1, thereby enabling rapid polymerization using silane coupling even at low temperatures. Therefore, it is believed that when a photosensitive resin composition comprising the copolymer disclosed herein is used for photolithography, a cured product with high hardness is formed, and excellent patterning properties are exhibited.

[0031] The copolymer described above may further include repeating structural unit A3, which has an acidic group at the end of the side chain. By including repeating structural unit A3, the effects of this disclosure can be obtained more reliably.

[0032] The structural unit A3 can be the structural unit shown in the following general formula (3). When the structural unit A3 is the structural unit shown in the following general formula (3), it can be copolymerized with structural units A1 and A2 according to known methods to obtain a stable copolymer.

[0033]

[0034] (In equation (3), R) 1 It is hydrogen or methyl, X 1 It is a single bond or a linking group with 1 to 10 carbon atoms.

[0035] In the above copolymer, the above structural unit A2 can be a structural unit represented by the following general formula (II).

[0036]

[0037] (In equation (II), R) 1 It is hydrogen or methyl, R 2 It is a (poly)oxyolefin with 2 to 4 carbon atoms, R 3 It is the chemical structure shown in the following general formula (4), R 4 It is a hydrocarbon group or phenyl group with 1 to 10 carbon atoms, R 7 (It can be hydrogen, a hydrocarbon group with 1 to 10 carbon atoms that can be substituted by a phenyl group, or a phenyl group.)

[0038]

[0039] (In equation (4), R) 5 It is a hydrocarbon group with 1 to 10 carbon atoms, R 6 It consists of hydrogen, a hydrocarbon group with 1 to 10 carbon atoms, a phenyl group, or a cyclohexyl group.

[0040] When structural unit A2 has these structures, the effects of this disclosure can be reliably obtained. Furthermore, industrially available raw materials can be used to produce copolymers with stable quality.

[0041] In the above copolymer, the above structural unit A1 can be a structural unit represented by the following general formula (I).

[0042]

[0043] (In equation (I), R) 1 It is hydrogen or methyl, X 2 It is an alkylene group with 1 to 10 carbon atoms, R8 It is an alkoxy group with 1 to 10 carbon atoms, R 9 (It is a hydrocarbon group with 1 to 10 carbon atoms, where 'a' is an integer from 1 to 3.)

[0044] When structural unit A1 is this structure, the effects of this disclosure can be reliably obtained. Furthermore, industrially available raw materials can be used to produce copolymers with stable quality.

[0045] The weight-average molecular weight (Mw) of the above copolymers can be between 3,000 and 20,000. When the weight-average molecular weight (Mw) is within this range, the copolymer has a moderate viscosity, making it easy to use in photosensitive resin compositions and exhibiting excellent photolithography properties.

[0046] In the above copolymer, when the molar ratio (containment ratio) of the above structural unit A1, the above structural unit A2, and the above structural unit A3 is set to k:l:m, it can be k:l:m = 30~80:5~40:10~40. When each structural unit is included within this range, the effects of this disclosure can be obtained more reliably.

[0047] The photosensitive resin composition disclosed herein comprises: a polymer containing at least a repeating structural unit A1 represented by the following general formula (1),

[0048] Polymers comprising at least the repeating structural unit A2 shown in general formula (2) below, and

[0049] Photoacid generator (B).

[0050]

[0051]

[0052] (In equations (1) and (2), R) 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 (This refers to a chemical structure with a terminal group other than an alkoxysilyl group that generates a hydroxyl group through acid dissociation.)

[0053] When the photosensitive resin composition disclosed herein is used for photolithography, a hard cured product is formed at low temperature, and excellent patterning properties are exhibited.

[0054] The above-described photosensitive resin composition may further comprise a monomer (C) having at least one of an unsaturated double bond and an alkoxysilyl group within its molecule. According to this configuration, the effects of this disclosure can be obtained more reliably.

[0055] The polymer in the above-described photosensitive resin composition may be a copolymer comprising the repeating structural unit A1 and the repeating structural unit A2. This copolymer constitutes a photosensitive resin composition that forms a cured product with high hardness at low temperatures and exhibits excellent patternability.

[0056] The copolymer in the above-mentioned photosensitive resin composition may be a copolymer that further includes the structural unit A3 shown in the following general formula (3).

[0057]

[0058] (In equation (3), R) 1 It is hydrogen or methyl, X 1 It is a single bond or a linking group with 1 to 10 carbon atoms.

[0059] This copolymer is equivalent to the copolymer described above and has the same effect.

[0060] The above-described photosensitive resin composition may further include a photopolymerization initiator (D). By including the polymerization initiator, a photosensitive resin composition that is easy to handle and suitable for photolithography is formed.

[0061] The above-mentioned photosensitive resin composition may further include a monofunctional alcohol without carboxyl groups and N-H bonds as a solvent. With this configuration, a photosensitive resin composition with the above-mentioned effects and excellent storage stability can be obtained.

[0062] The pattern-forming material disclosed herein may comprise the above-described photosensitive resin composition. The above-described photosensitive resin composition is suitable for use as a pattern-forming material (resist material).

[0063] The cured product disclosed herein can be obtained from the above-described photosensitive resin composition. The cured product may be an optical spacer, spacer wall material, lens material, interlayer insulating film material, protective film material, optical waveguide material, or planarization film material.

[0064] The image display device disclosed herein may include the aforementioned cured material.

[0065] [Specific examples of implementation methods]

[0066] The copolymers and photosensitive resin compositions of this disclosure are described in more detail below. It should be noted that in this specification, (meth)acrylic acid refers to acrylic acid or methacrylic acid, (meth)acryloyl refers to acryloyl or methacryloyl, (meth)acrylic acid refers to acrylic acid or methacrylic acid, and (meth)acrylate refers to acrylate or methacrylate. Furthermore, in this specification, the number of carbon atoms in the parent compound refers to the number of carbon atoms in the groups that form the main backbone, excluding substituents.

[0067] (Copolymer)

[0068] The copolymer disclosed herein is a (meth)acrylate copolymer. The copolymer disclosed herein is a copolymer comprising repeating structural unit A1 as shown in general formula (1) and repeating structural unit A2 as shown in general formula (2). The copolymer disclosed herein preferably further comprises structural unit A3 as shown in general formula (3). That is, the copolymer disclosed herein is a copolymer comprising structural unit A1 and structural unit A2, and preferably further comprising structural unit A3.

[0069]

[0070]

[0071] (In equations (1) and (2), R) 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 (This refers to a chemical structure with a terminal group other than an alkoxysilyl group that generates a hydroxyl group through acid dissociation.)

[0072]

[0073] (In equation (3), R) 1 It is hydrogen or methyl, X 1 It is a single bond or a linking group with 1 to 10 carbon atoms.

[0074] (Structural Unit A1)

[0075] Structural unit A1 is the repeating unit shown in the above general formula (1), in which R 1 It is either hydrogen or methyl. That is, structural unit A1 is a repeating unit derived from a monomer that is a (meth)acrylic acid derivative. 1 It has a chemical structure with an alkoxysilyl group at the end. A 1 It consists of a terminal alkoxysilyl group and a linking group connecting the alkoxysilyl group to the oxygen atom of the ester bond.

[0076] As a linking group between an alkoxysilyl group and the oxygen atom of an ester bond, there are no particular limitations as long as it is a linking group with one or more carbon atoms and can be linked to an alkoxysilyl group. Examples of linking groups include linear or branched aliphatic saturated or unsaturated hydrocarbon groups, alicyclic saturated or unsaturated hydrocarbon groups (including bridged rings and fused rings), aromatic hydrocarbon groups, organic groups obtained by substituting a portion of the carbon atoms constituting the above hydrocarbon groups with heteroatoms (e.g., oxygen atoms, nitrogen atoms, and sulfur atoms), and organic groups formed by the bonding of two or more of these. In addition, the above hydrocarbon groups or organic groups can have various substituents (e.g., halogen groups, hydroxyl groups, carboxyl groups, amino groups, alkyl groups, alkenyl groups, alkoxy groups, and aryl groups) and functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, and carbamate bonds).

[0077] Structural unit A1 is preferably the structural unit shown in the following general formula (I).

[0078]

[0079] (In equation (I), R) 1 It is hydrogen or methyl, X 2 It is an alkylene group with 1 to 10 carbon atoms, R 8 It is an alkoxy group with 1 to 10 carbon atoms, R 9 (It is a hydrocarbon group with 1 to 10 carbon atoms, where 'a' is an integer from 1 to 3.)

[0080] As X 2 Alkylenes, which have 1 to 10 carbon atoms, include alkylenes, alkenyl oxides, and arylenes. Examples of alkylenes include methylene, ethylene, n-propylene, n-butylene, n-hexylene, n-heptylene, n-octylene, and n-dodecylene. Examples of alkenyl oxides include vinyl oxides, propenyl oxides, and butenyl oxides.

[0081] As R 8 This refers to alkoxy groups with 1 to 10 carbon atoms, specifically including methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, n-pentoxy, isopentoxy, neopentoxy, tert-pentoxy, cyclopentoxy, n-hexyloxy, isohexyloxy, cyclohexyloxy, n-heptoxy, cycloheptoxy, methylcyclohexyloxy, n-octoxy, cyclooctoxy, n-nonoxy, 3,3,5-trimethylcyclohexyloxy, n-decoxy, cyclodecoxy, etc. Among these, methoxy, ethoxy, n-propoxy, and isopropoxy are preferred.

[0082] As R 9This refers to hydrocarbon groups with 1 to 10 carbon atoms, including linear or branched aliphatic saturated or unsaturated hydrocarbon groups, alicyclic saturated or unsaturated hydrocarbon groups, etc. Specifically, for example, alkyl groups, examples of which include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, n-hexyl, isohexyl, cyclohexyl, n-heptyl, cycloheptyl, methylcyclohexyl, n-octyl, cyclooctyl, n-nonyl, 3,3,5-trimethylcyclohexyl, n-decyl, cyclodecyl, benzyl, methylbenzyl, dimethylbenzyl, trimethylbenzyl, phenethyl, 2-phenylisopropyl, etc.

[0083] a is an integer from 1 to 3, preferably 2 or 3. When a is 3, it is a trialkoxysilane. When a is 2, it becomes a structure in which two alkoxy groups and one hydrocarbon group (especially an alkyl group) are bonded to a Si atom.

[0084] (Structural Unit A2)

[0085] Structural unit A2 is a repeating structure shown in the above general formula (2), in which R 1 It is either hydrogen or methyl. That is, structural unit A2 is a repeating unit derived from a monomer that is a (meth)acrylic acid derivative. 2 It is a chemical structure with a terminal group other than alkoxysilyl groups that generate hydroxyl groups through acid dissociation. That is, structural unit A2 is a structural unit with hydroxyl groups protected by a protecting group that is deprotected by acid. The protecting group can be deprotected by a strong acid provided by an acid-generating agent contained in or added to the photosensitive resin composition during photolithography.

[0086] While not limited by any specific theory, it is believed that in the copolymers disclosed herein, crosslinking is promoted by the reaction of hydroxyl groups generated through deprotection of the protecting group of structural unit A2, or by intermediates generated during the deprotection process, with the alkoxysilyl group of structural unit A1. It is believed that this configuration results in excellent photolithography when the copolymers of this disclosure are used in photosensitive resin compositions.

[0087] The protecting group of the hydroxyl group contained in structural unit A2 can be a structure known as a protecting group of hydroxyl group, such as tetrahydropyranyl, tert-butyldimethylsilyl, methoxymethyl, methoxyethoxymethyl, acetyl, neopentanoyl, benzoyl, benzyl, and their derivatives.

[0088] Specifically, structural unit A2 can be the structural unit shown in the following general formula (II).

[0089]

[0090] (In equation (II), R) 1It is hydrogen or methyl, R 2 It is a (poly)oxyolefin with 2 to 4 carbon atoms, R 3 It is the chemical structure shown in the following general formula (4), R 4 It is a hydrocarbon group or phenyl group with 1 to 10 carbon atoms, R 7 (It can be hydrogen, a hydrocarbon group with 1 to 10 carbon atoms that can be substituted by a phenyl group, or a phenyl group.)

[0091]

[0092] (In equation (4), R) 5 It is a hydrocarbon group with 1 to 10 carbon atoms, R 6 It consists of hydrogen, a hydrocarbon group with 1 to 10 carbon atoms, a phenyl group, or a cyclohexyl group.

[0093] As R 2 That is, (poly)oxyolefin, examples of which include vinyl oxide with a repeating number of 1 to 15, propylene oxide with a repeating number of 1 to 15, and butenyl oxide with a repeating number of 1 to 15. R 2 It can contain various oxidized alkenyl groups with different numbers of carbon atoms. For example, R 2 It can be a structure formed by linking vinyl oxide and propylene oxide groups. When R 2 When multiple oxidized alkenyl groups with different numbers of carbon atoms are included, each oxidized alkenyl group can exist in block form or in random form.

[0094] R 3 It is the structure shown in the above general formula (4), which serves as R in general formula (4). 5 Specifically, examples can be given of R as a general formula (I). 9 The structures given are the same. Preferably, the alkyl group has 1 to 3 carbon atoms, specifically methyl, ethyl, n-propyl, or isopropyl. As R in general formula (4) 6 Specifically, examples include hydrogen, hydrocarbon groups with 1 to 10 carbon atoms, phenyl, or cyclohexyl. As hydrocarbon groups with 1 to 10 carbon atoms, examples include those represented by R in general formula (I). 9 Among the hydrocarbon groups mentioned, methyl, ethyl, n-propyl, and isopropyl are preferred.

[0095] R 4 It is hydrogen, a hydrocarbon group having 1 to 10 carbon atoms, or a phenyl group. Examples of hydrocarbon groups having 1 to 10 carbon atoms include R in general formula (I). 9 The hydrocarbon groups mentioned are the same hydrocarbon groups. Among them, R 4 Preferably, it is hydrogen or phenyl.

[0096] R 7It is hydrogen, a hydrocarbon group with 1 to 10 carbon atoms that can be substituted by a phenyl group, or a phenyl group. Examples of hydrocarbon groups with 1 to 10 carbon atoms that are not substituted by a phenyl group include R in general formula (I). 9 Among the hydrocarbon groups mentioned, saturated hydrocarbon groups with 6 to 10 carbon atoms are preferred, namely n-hexyl, isohexyl, cyclohexyl, n-heptyl, cycloheptyl, methylcyclohexyl, n-octyl, cyclooctyl, n-nonyl, 3,3,5-trimethylcyclohexyl, n-decyl, etc. Examples of hydrocarbon groups substituted with phenyl groups include phenylethyl and phenylpropyl.

[0097] R 4 and R 7 Preferably, at least one or both are hydrogen.

[0098] (Structural Unit A3)

[0099] Structural unit A3 is a repeating structure shown in the above general formula (3), in which R 1 It is either hydrogen or methyl. That is, structural unit A3 is a repeating unit derived from a monomer that is a (meth)acrylic acid derivative. Structural unit A3 is a structural unit with an acid group at the end of the side chain, specifically a carboxyl group. Structural unit A3 is a structural unit of a (meth)acrylic acid-containing ester. By including structural unit A3 in the copolymer, a photosensitive resin composition with excellent photolithography properties can be formed.

[0100] Linking group X in structural unit A3 1 It is a single bond or a linking group with 1 to 10 carbon atoms. When the linking group X... 1 When it is a single bond, structural unit A3 is a structural unit that uses a structure derived from (meth)acrylic acid as a unit. When the connecting group X... 1 When the number of carbon atoms in the group is 1 or more, the linking group X 1 There are no particular restrictions on any group that can be linked to a carboxyl group. Examples of linking groups include straight-chain or branched aliphatic saturated or unsaturated hydrocarbon groups with 1 to 10 carbon atoms, alicyclic saturated or unsaturated hydrocarbon groups (including bridged rings and fused rings), aromatic hydrocarbon groups, organic groups obtained by replacing part of the carbon atoms constituting the hydrocarbon group with heteroatoms (such as oxygen atoms, nitrogen atoms, and sulfur atoms), and organic groups formed by the bonding of two or more of these. In addition, hydrocarbon groups or organic groups can have various substituents (such as halogen groups, hydroxyl groups, carboxyl groups, amino groups, alkyl groups, alkenyl groups, alkoxy groups, and aryl groups) and functional groups (such as ester bonds, amide bonds, ether bonds, thioether bonds, and carbamate bonds).

[0101] In structural unit A3, the linking group X 1 The terminal carboxyl group can specifically be, for example, the following structure.

[0102]

[0103]

[0104] In the copolymer disclosed herein, the proportions of structural unit A1, structural unit A2, and structural unit A3 are not particularly limited. When the molar ratio (content ratio) of structural unit A1, structural unit A2, and structural unit A3 is set as k:l:m, k:l:m is preferably 30–80:5–40:10–40, more preferably 50–75:5–30:15–30. The total content of structural unit A1 and structural unit A2 relative to the total content of the copolymer is preferably 60 mol% or more, more preferably 90 mol% or less. Furthermore, the content of structural unit A1 is preferably greater than the content of structural unit A2. Specifically, the content of structural unit A1 is preferably 1.5 times or more, more preferably 2 times or more, relative to the content of structural unit A2.

[0105] (Other structural units)

[0106] In addition to structural units A1, A2, and A3, the copolymers disclosed herein may also contain additional structural units Ax. Monomers that serve as sources of structural units Ax include, for example, monomers containing carboxylic anhydride groups such as maleic anhydride and itaconic anhydride; alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, benzyl methacrylate, lauryl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, ethoxyethyl methacrylate, and glycidyl methacrylate; and alicyclic methacrylates such as cyclohexyl methacrylate, isobornyl methacrylate, and dicyclopentenyl methacrylate. Alternatively, styrene, cyclohexylmaleimide, phenylmaleimide, methylmaleimide, ethylmaleimide, n-butylmaleimide, laurylmaleimide, and silicone-containing monomers can be used as comonomers. These monomers can be used alone or in combination of two or more.

[0107] The total content of structural units A1, A2, and A3 in the copolymer of this disclosure is preferably 50-100 mol% of all repeating structural units in the copolymer, more preferably 75-100 mol%. The copolymer of this disclosure is more preferably composed of structural units A1, A2, and A3. When the copolymer of this disclosure contains structural unit Ax other than structural units A1, A2, and A3, from the viewpoint of sensitivity and reproducibility, the content of structural unit Ax relative to all repeating structural units is preferably 0-50 mol%, more preferably 0-25 mol%, further preferably 0-15 mol%, and particularly preferably 0-10 mol%.

[0108] (Characteristics of copolymers)

[0109] The weight-average molecular weight (Mw) of the copolymers disclosed herein is not particularly limited, but from the viewpoint of sensitivity and reproducibility, it is preferably 3,000 to 20,000, more preferably 5,000 to 10,000. The weight-average molecular weight is a value converted to polystyrene using gel permeation chromatography (GPC), and is a value determined according to JIS K7252-4.

[0110] The acid value of the copolymer disclosed herein is not particularly limited, but from the viewpoint that it can be developed in a short time even when using a weakly alkaline developer, it is preferably 10 to 120 mg KOH / g, more preferably 20 to 80 mg KOH / g. The acid value in this invention represents the mass (mg) of potassium hydroxide required to neutralize the acidic component contained in 1 g of the copolymer, and is a theoretical value calculated based on the molecular weight and the number of functional groups (acid groups) per molecule of the target material. Specifically, the acid value of the target material is the value obtained by [the number of moles of acid groups in the copolymer (mmol)] × [56.11 / the amount of the target material (g)].

[0111] (Method for manufacturing copolymers)

[0112] The copolymers of the present invention can generally be manufactured according to known methods for manufacturing acrylate resins. Specifically, for example, they can be synthesized by copolymerizing monomers containing alkoxysilyl groups of (meth)acrylates and monomers containing groups of (meth)acrylates that generate hydroxyl groups through acid dissociation using heat, light, or the like.

[0113] (Photosensitive resin composition)

[0114] The photosensitive resin composition disclosed herein comprises a polymer and a monomer as the main components constituting the cured product after polymerization. Additionally, the photosensitive resin composition may contain components such as a photoacid generator and a photopolymerization initiator, which function to initiate and promote the polymerization reaction.

[0115] (polymer)

[0116] The photosensitive resin composition disclosed herein contains a polymer comprising at least a polymer containing a repeating structural unit A1 as shown in general formula (1) below and a polymer comprising at least a repeating structural unit A2 as shown in general formula (2) below. The polymer containing structural unit A1 and the polymer containing structural unit A2 may be different polymers from each other, or they may be contained in a single polymer. That is, the polymer contained in the photosensitive resin composition disclosed herein may be a copolymer containing repeating structural unit A1 and repeating structural unit A2.

[0117]

[0118]

[0119] (In formulas (1) and (2), R1 is hydrogen or methyl, A1 is a chemical structure with an alkoxysilyl group at the end, and A2 is a chemical structure with a group other than alkoxysilyl group at the end that generates a hydroxyl group through acid dissociation.)

[0120] The copolymer containing structural units A1 and A2 is the copolymer described above. The copolymer may further contain structural unit A3 as shown in general formula (3) below. Even when the copolymer further contains structural unit A3, the same copolymer as the copolymer described above may be used.

[0121]

[0122] (In equation (3), R) 1 It is hydrogen or methyl, X 1 It is a single bond or a linking group with 1 to 10 carbon atoms.

[0123] The proportion of the aforementioned polymers in the photosensitive resin composition (or the total proportion when multiple polymers are contained) is not particularly limited, but may be 40% to 90% by mass, preferably 50% to 80% by mass, relative to the solids content of the photosensitive resin composition. Here, the solids content of the photosensitive resin composition refers to the composition after removing the solvent from the photosensitive resin composition. The solids content of the photosensitive resin composition can be determined, for example, by measuring the amount of residual solids after heating the photosensitive resin composition containing the solvent at 130°C for 1 hour.

[0124] (monomer)

[0125] The photosensitive resin composition disclosed herein preferably contains monomers having at least one of unsaturated double bonds and alkoxysilyl groups within the molecule. By including monomers, the hardness and photoresistivity of the cured product can be improved. It is believed that the photosensitive resin composition disclosed herein, in addition to the above-mentioned polymer, also contains monomers, thereby achieving a good balance between the hydrolysis and condensation reaction of the alkoxysilyl groups in the polymer and the polymerization of the monomers, thus achieving both excellent photoresistivity and high hardness.

[0126] The monomer can be either an intramolecular monomer having both an unsaturated double bond and an alkoxysilyl group, or either of these. The photosensitive resin composition disclosed herein can comprise monomers having both an intramolecular unsaturated double bond and alkoxysilyl groups. It should be noted that, in this specification, monomers include not only monomers formed from a single repeating unit in a molecule, but also oligomers containing a smaller number of repeating units. For example, oligomer-type acrylate-containing silane coupling agents are preferably used as monomers having both an intramolecular unsaturated double bond and an alkoxysilyl group.

[0127] As monomers containing both unsaturated double bonds and alkoxysilyl groups within their molecules, known silane coupling agents such as (meth)acrylate silane coupling agents, vinyl silane coupling agents, and styrene silane coupling agents can be used. More specifically, examples of (meth)acrylate silane coupling agents include 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, and 3-acryloyloxypropyltrimethoxysilane. Examples of vinyl silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinylalkoxysilanes such as vinylalkoxysilane, vinylmethyldimethoxysilane, and vinyldimethylmethoxysilane. Examples of styrene silane coupling agents include p-styrenetrimethoxysilane.

[0128] Examples of monomers containing intramolecular unsaturated double bonds include (meth)acrylic acid; alkyl methacrylates such as methoxyethyl methacrylate, methoxybutyl methacrylate, and ethoxybutyl methacrylate; hydroxyl-containing (meth)acrylates such as 2-hydroxyethyl methacrylate and hydroxypropyl methacrylate; tertiary amino-containing (meth)acrylic acid esters such as N,N-dimethylaminoethyl methacrylate, N,N-diethylaminoethyl methacrylate, and N,N-dimethylaminopropyl methacrylate; alicyclic (meth)acrylates such as cyclopentyl methacrylate, cyclohexyl methacrylate, and isobornyl methacrylate; and fluorine-containing unsaturated monomers such as octafluoropentyl methacrylate and perfluorocyclohexyl methacrylate. Monomers with a single unsaturated group include: difunctional unsaturated monomers such as vinylbenzene, polyethylene glycol di(meth)acrylate, and dimethyloltricyclodecane diacrylate; epoxy-containing unsaturated monomers such as glycidyl methacrylate and allyl glycidyl ether; unsaturated monomers with an amide group such as acrylamide, N-hydroxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, N-methylacrylamide, N,N-dimethylacrylamide, and N-isopropylacrylamide; nitrogen-containing unsaturated monomers such as N-vinylpyrrolidone, N-vinylimidazolium, and N-vinylcarbazole; aromatic unsaturated monomers such as styrene, α-methylstyrene, benzyl acrylate, benzyl methacrylate, and phenoxyethyl acrylate; and unsaturated monomers with a single unsaturated group such as isocyanate-terminated unsaturated monomers. Additionally, monomers with three or more unsaturated double bonds include triazine isocyanurate, trimethylolpropane triacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate. These monomers can be used in single or multiple ways.

[0129] Examples of monomers containing an intramolecular alkoxysilane include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane. 3-Triethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, [( 3-Ethyl-3-oxetane(butyl)methoxy]propyltrimethoxysilane, [(3-ethyl-3-oxetane)methoxy]propyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-ureidopropyltriethoxysilane, 3-isocyanate propyltriethoxysilane, 3-trimethoxysilylpropylpropylsuccinic acid, N-tert-butyl-3-(3-trimethoxysilylpropyl)succinimide, etc. These monomers can be used individually or in combination with two or more.

[0130] The proportion of monomers in the photosensitive resin composition (or the total proportion when multiple monomers are contained) is not particularly limited. For example, it can be 10% to 60% by mass relative to the solid content of the photosensitive resin composition, preferably 20% to 50% by mass. When the photosensitive resin composition contains 20% or more of monomers, it is preferred from the viewpoint of easily achieving excellent patternability. If the proportion of monomers is 50% or less, it is preferred from the viewpoint of easily obtaining a cured product with high hardness.

[0131] (catalyst)

[0132] The photosensitive resin composition disclosed herein is characterized in that it preferably contains an acid catalyst, particularly a photoacid generator, to promote the polymerization reaction. Examples of photoacid generators include known compounds that efficiently generate acids upon exposure, such as iodonium salts like diazonium salts and diphenyliodohexafluorophosphate; sulfonium salts like triphenylsulfonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, and triphenylsulfonium methanesulfonate; sulfonates like 1-phenyl-1-(4-methylphenyl)sulfonyloxy-1-benzoylmethane, 1,2,3-trisulfonyloxymethylbenzene, 1,3-dinitro-2-(4-phenylsulfonyloxymethyl)benzene, and 1-phenyl-1-(4-methylphenylsulfonyloxymethyl)-1-hydroxy-1-benzoylmethane; oxathiazole derivatives, s-triazine derivatives, disulfone derivatives like diphenyl disulfone, imide compounds, oxime sulfonates, diazonoquinone, and benzoin toluene sulfonate. These photoacid generators can be used alone or in combination of two or more.

[0133] To promote the polymerization reaction, the photosensitive resin composition disclosed herein may contain an acid catalyst other than a photoacid generator. This acid catalyst may be a compound selected from Brønsted acids and / or Lewis acids, or a salt thereof, or a solvate thereof. Examples of acid catalysts include, for instance, protic acids such as dinonylnaphthalene disulfonic acid, dinonylnaphthalene (mono)sulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfonic acid (PTS), phosphoric acid, sulfuric acid, and acetic acid, or their salts or solvates thereof, preferably p-toluenesulfonic acid, pyridinium p-toluenesulfonic acid, or their hydrates. One or more acid catalysts may be used.

[0134] The content of the catalyst is not particularly limited, but is preferably 0.1 to 5% by mass, more preferably 0.5 to 4% by mass, and even more preferably 1 to 3% by mass, relative to the solid content of the photosensitive resin composition.

[0135] (Polymerization initiator)

[0136] The photosensitive resin composition disclosed herein may contain a photopolymerization initiator. There are no particular limitations on photopolymerization initiators. Examples include benzoin, benzoin methyl ether, benzoin ethyl ether, and other benzoin derivatives and their alkyl ethers; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone; anthraquinones such as 2-methylanthraquinone, 2-pentylanthraquinone, 2-tert-butylanthraquinone, and 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides and xanthones, etc. These photopolymerization initiators can be used in one or more combinations.

[0137] There is no particular limitation on the proportion of the photopolymerization initiator, but it is preferably 0.1 to 10% by mass, more preferably 0.5 to 9% by mass, and even more preferably 1 to 8% by mass relative to the solid content of the photosensitive resin composition.

[0138] Photopolymerization initiators can be added to the photosensitive resin composition. Examples of photopolymerization initiators include trifunctional thiols such as 1,3,5-tris(3-mercaptopropionyloxyethyl)-isocyanurate, 1,3,5-tris(3-mercaptobutyloxyethyl)-isocyanurate (manufactured by Showa Denko, KARENZ MT (registered trademark) NR1), and trimethylolpropane tris(3-mercaptopropionate); tetrafunctional thiols such as pentaerythritol tetras(3-mercaptopropionate) and pentaerythritol tetras(3-mercaptobutyrate) (manufactured by Showa Denko, KARENZ MT (registered trademark) PEI); and polyfunctional thiols such as dipentaerythritol hexa(3-propionate). One or more of these photopolymerization initiators can be used.

[0139] Thermal polymerization initiators can be added to the photosensitive resin composition. Examples of thermal polymerization initiators include organic peroxides such as cumene hydroperoxide, dicumyl peroxide, di-tert-butyl peroxide, lauroyl peroxide, benzoyl peroxide, tert-butyl peroxyisopropyl carbonate, tert-butyl peroxide-2-ethylhexanoate, and tert-amyl peroxide-2-ethylhexanoate; and azo compounds such as 2,2'-azobis(isobutyronitrile), 1,1'-azobis(cyclohexaneformitrile), 2,2'-azobis(2,4-dimethylpentanonitrile), and dimethyl 2,2'-azobis(2-methylpropionate). One or more of these thermal polymerization initiators can be used.

[0140] (solvent)

[0141] The photosensitive resin composition disclosed herein may contain a solvent. Examples of solvents include ethers such as tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and 3-methoxybutyl acetate; alcohols such as methanol, ethanol, isopropanol, n-butanol, ethylene glycol monomethyl ether, and propylene glycol monomethyl ether; aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; and chloroform and dimethyl sulfoxide. Only one solvent may be used, or two or more may be used in combination.

[0142] From the viewpoint of improving the storage stability of photosensitive resin compositions, solvents are preferably alcohols, and particularly preferably monofunctional alcohols that do not contain carboxyl groups and / or amino groups (N-H bonds). The (co)polymers contained in the photosensitive resin compositions disclosed herein have alkoxysilyl groups. The alkoxysilyl groups are decomposed by water contained in the solvent to generate silanols, which undergo a condensation reaction. This condensation reaction leads to an increase in viscosity and gelation of the photosensitive resin composition, and is therefore undesirable. In this respect, when a monofunctional alcohol that does not contain carboxyl groups and / or amino groups (N-H bonds) is used as a solvent, the condensation reaction of the alkoxysilyl groups can be suppressed, and storage stability is improved.

[0143] The solvent content in the photosensitive resin composition disclosed herein is not particularly limited and can be appropriately set according to the optimal viscosity when using the photosensitive resin composition.

[0144] (Other ingredients)

[0145] Without impairing the effects of this disclosure, the photosensitive resin composition of this disclosure may also contain fillers such as aluminum hydroxide, talc, clay, and barium sulfate, surface conditioners (surfactants), dyes, pigments, defoamers, leveling agents, sensitizers, release agents, lubricants, plasticizers, antioxidants, ultraviolet absorbers, flame retardants, polymerization inhibitors, thickeners, and dispersants, and other known additives.

[0146] (Uses of photosensitive resin compositions)

[0147] The photosensitive resin composition disclosed herein can form a cured material with high hardness and excellent scratch resistance, and has excellent photolithographic properties (patterning development characteristics / through-hole formation properties), therefore it is preferred as a patterning material. The patterning material includes a photoresist material.

[0148] The cured product disclosed herein can be obtained by curing the above-described photosensitive resin composition. The cured product can be obtained according to the procedures commonly used in the curing of photocurable resins. For example, a method can be employed whereby the photosensitive resin composition is injected into a molding die (resin mold) or coated onto a substrate (substrate) or various functional layers to form a desired shape, and then irradiated with light (e.g., ultraviolet light) to cure the photosensitive resin composition. The curing conditions can be adjusted according to the photosensitive resin composition used.

[0149] The cured product disclosed herein is suitable for use as an optical spacer, spacer wall material, lens material, interlayer insulating film material, protective film material, optical waveguide material, or planarization film material, and is particularly suitable for use as an optical spacer. There are no particular limitations on the method of forming the optical spacer. For example, a photosensitive resin composition can be coated onto a substrate such as glass or a transparent plastic film and dried to form a coating, followed by photolithography. In photolithography, for example, a photomask is placed on the coating, the coating is photocured by irradiation with ultraviolet light, an alkaline aqueous solution is dispersed on the ultraviolet-irradiated coating to dissolve and remove the unexposed areas, the remaining exposed areas are washed with water and developed, thereby forming the optical spacer. Post-baking can then be performed.

[0150] [Example]

[0151] The copolymer and photosensitive resin compositions of this disclosure are further illustrated below by way of examples, but the present invention is not limited to these examples.

[0152] [Example A-1] Synthesis of copolymer A-1

[0153] The copolymer shown in formula (A-1) was synthesized by the following manufacturing method. The molar ratio (theoretical value) of k:l:m in formula (A-1) is 50:30:20.

[0154]

[0155] 64.7 g of triethoxy(3-methacryloyloxypropyl)silane, 7.7 g of methacrylic acid, 27.6 g of phenoxyethyl methacrylate, and 300 g of propylene glycol monomethyl ether were added to a glass flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, and thermometer. After purging the gas phase of the system with nitrogen, 13 g of 2,2'-azobis(2,4-dimethylpentanonitrile) was added, and the mixture was heated at 65°C and reacted at the same temperature for 8 hours to obtain a solution containing 20% ​​by mass of alkali-soluble resin 1. Molecular weight determination by GPC showed that the weight-average molecular weight (Mw) of alkali-soluble resin 1 was 7000. Furthermore, the acid value of alkali-soluble resin 1 was 46 mg KOH / g.

[0156] [Example A-2] Synthesis of copolymer A-2

[0157] The molar ratio (theoretical value) of k:l:m in copolymer A-1 was changed to 75:5:20. Otherwise, the same synthesis was carried out as in Example 1 to obtain copolymer A-2.

[0158] [Example A-3] Synthesis of copolymer A-3

[0159] The copolymer shown in formula (A-3) was synthesized in the same manner as in Example 1, except that trimethoxy(3-methacryloyloxypropyl)silane was used instead of triethoxy(3-methacryloyloxypropyl)silane. The molar ratio (theoretical value) of k:l:m in formula (A-3) is 50:30:20.

[0160]

[0161] [Example A-4] Synthesis of copolymer A-4

[0162] The copolymers shown in Formula (A-4) were synthesized in the same manner as in Example 1, except that diethoxymethyl(3-methacryloyloxypropyl)silane was used instead of triethoxy(3-methacryloyloxypropyl)silane. The molar ratio (theoretical value) of k:l:m in Formula (A-4) is 50:30:20.

[0163]

[0164] [Example A-5] Synthesis of copolymer A-5

[0165] Furthermore, methyl methacrylate was used, and otherwise, the copolymer shown in formula (A-5) was synthesized in the same manner as in Example 1. The molar ratio (theoretical value) of k:l:m:n in formula (A-5) is 50:15:20:15.

[0166]

[0167] [Example A-6] Synthesis of copolymer A-6

[0168] The copolymers shown in Formula (A-6) were synthesized in the same manner as in Example 1, except that ethoxylated o-phenylphenol acrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A-6) is 50:30:20.

[0169]

[0170] [Example A-7] Synthesis of copolymer A-7

[0171] The copolymer shown in Formula (A-7) was synthesized in the same manner as in Example 1, except that α-acryloyl-ω-[4-(2-phenylpropane-2-yl)phenoxy]poly(ethylene oxide) was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A-7) is 50:30:20.

[0172]

[0173] [Example A-8] Synthesis of copolymer A-8

[0174] The copolymers shown in Formula (A-8) were synthesized in the same manner as in Example 1, except that nonylphenoxy polyethylene glycol acrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A-8) is 50:30:20.

[0175]

[0176] [Example A-9] Synthesis of copolymer A-9

[0177] The copolymer shown in formula (A-9) was synthesized in the same manner as in Example 1, except that 2-(1-ethoxyethoxy)ethyl methacrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in formula (A-9) is 50:30:20.

[0178]

[0179] [Example A-10] Synthesis of copolymer A-10

[0180] The copolymer shown in Formula (A-10) was synthesized in the same manner as in Example 1, except that 2-(trimethylsilyloxy)ethyl methacrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A-10) is 50:30:20.

[0181]

[0182] [Example A-11] Synthesis of copolymer A-11

[0183] The copolymer shown in Formula (A-11) was synthesized in the same manner as in Example 1, except that 2-(tert-butyloxycarbonyloxy)ethyl methacrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A-11) is 50:30:20.

[0184]

[0185] [Comparative Example A'-1] Synthesis of copolymer A'-1

[0186] The copolymer shown in Formula (A'-1) was synthesized using dicyclopentyl methacrylate, 3,4-epoxycyclohexyl methacrylate, and methacrylic acid, except that, in the same manner as in Example 1. The molar ratio (theoretical value) of k:l:m in Formula (A'-1) is 35:38:27.

[0187]

[0188] [Comparative Example A'-2] Synthesis of copolymer A'-2

[0189] The copolymer shown in Formula (A'-2) was synthesized in the same manner as in Example 1, except that phenyl methacrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A'-2) is 50:30:20.

[0190]

[0191] [Comparative Example A'-3] Synthesis of copolymer A'-3

[0192] The copolymers shown in Formula (A'-3) were synthesized in the same manner as in Example 1, except that 2-hydroxyethyl methacrylate was used instead of phenoxyethyl methacrylate. The molar ratio (theoretical value) of k:l:m in Formula (A'-3) is 50:30:20.

[0193]

[0194] <<Preparation of Photosensitive Resin Compositions>>

[0195] For the solutions containing copolymers A-1 to A-11 of this disclosure and copolymers A'-1 to A'-3 outside the scope of this disclosure, the raw materials listed in Tables 1 to 3 are mixed in the proportions listed in Tables 1 to 3 to prepare a photosensitive resin composition. It should be noted that the values ​​in Table 1 are in parts by mass. Mixing is carried out at room temperature, with ultraviolet light blocked in a manner that does not initiate polymerization. The raw materials listed in Tables 1 to 3 are as follows.

[0196] <Acrylic monomer>

[0197] b1-1: KR513 (Shin-Etsu Chemical Industry Co., Ltd., an oligomeric silane coupling agent containing acrylic acid groups)

[0198] b1-2:x-12-1050 (Shin-Etsu Chemical Industry Co., Ltd., a polyfunctional silane coupling agent containing acrylic acid groups)

[0199] b2-1: LIGHTACRYLATE DCP-A (Kyoei Chemical Co., Ltd., a bifunctional monomer with a tricyclic ring)

[0200] b2-2: ARONIX M-923 (produced by Dong-A Synthetic, the main component is a monomer with an isocyanuric acid backbone and two acrylate groups).

[0201] <Other monomers>

[0202] b3-1: KBM-9659 (Shin-Etsu Chemical Industry Co., Ltd., a silane coupling agent with isocyanurate groups)

[0203] <Photopolymerization Initiator>

[0204] C-1: Irgacure OXE01 (manufactured by BASF Japan, photoradical initiator)

[0205] <Acid Catalyst>

[0206] D-1: SP-606 (manufactured by ADEKA, photoacid generator)

[0207] <Solvent>

[0208] E: PGA (Propylene Glycol Monomethyl Ether)

[0209]

[0210]

[0211]

[0212] <<Evaluation of Photosensitive Resin Compositions>>

[0213] For the photosensitive resin compositions of Examples 1-17 and Comparative Examples 1-3 shown in Tables 1-3, photocurability, coating hardness (pencil hardness), patterning characteristics (pore formation), and stability were evaluated. The evaluation methods and criteria are as follows. The evaluation results are summarized in Tables 4-5.

[0214] [Photocurability]

[0215] (Evaluation Method)

[0216] The photosensitive compositions prepared in Examples 1-17 and Comparative Examples 1-3 were coated onto a 10cm × 10cm square glass substrate using a spin coater to achieve a final film thickness of 2.0 μm. The coatings were then dried under reduced pressure at room temperature using a vacuum drying apparatus (VCD). The coating was heated on a hot plate at 90°C for 2 minutes to completely remove the solvent. The resulting coatings were then exposed at an exposure gap of 200 μm and an exposure temperature of 100 mJ / cm². 2 Illuminance of ultra-high pressure mercury lamp at 365nm: 20mW / cm² 2 Then, develop with a 0.3% sodium carbonate aqueous solution for 60 seconds. The photocurability is evaluated using the residual film rate calculated according to the following formula.

[0217] Residual film yield after development (%) = (film thickness after development (μm) / film thickness after coating (μm)) × 100

[0218] (Evaluation Criteria)

[0219] A: The residual film rate (%) is over 90%.

[0220] B: Residual film rate (%) less than 90% and above 50%

[0221] C: Residual film rate (%) less than 50%

[0222] [Pencil Hardness]

[0223] (Evaluation Method)

[0224] The photosensitive resin compositions prepared in Examples 1-17 and Comparative Examples 1-3 were coated onto a 10cm × 10cm square glass substrate using a spin coater to achieve a final film thickness of 2.0 μm. The coatings were then dried under reduced pressure at room temperature using a vacuum drying apparatus (VCD). The coating was heated on a hot plate at 90°C for 2 minutes to completely remove the solvent. The resulting coating was then subjected to a pressure of 60 mJ / cm². 2 Illuminance of ultra-high pressure mercury lamp at 365nm: 20mW / cm² 2 Then, a post-bake at 120°C for 30 minutes is performed to create a substrate with a cured film. A pencil is used to scratch the substrate with the cured film at a 45-degree angle with a load of 750g for approximately 1 cm. The hardest scratch without leaving a mark is taken as the pencil hardness. The pencil hardness is evaluated according to the following criteria.

[0225] (Evaluation Criteria)

[0226] A: The pencil hardness is H or higher.

[0227] B: Pencil hardness is 2B or higher and less than HB.

[0228] C: Pencil hardness less than 3B

[0229] [Through-hole (patterned development characteristics)]

[0230] (Evaluation Method)

[0231] The photosensitive compositions prepared in Examples 1-17 and Comparative Examples 1-3 were coated onto a 10cm × 10cm square glass substrate using a spin coater to achieve a final film thickness of 2.0 μm. The coatings were then dried under reduced pressure at room temperature using a vacuum drying apparatus (VCD). The coating was heated on a hot plate at 90°C for 2 minutes to completely remove the solvent. The resulting coatings were then exposed at an exposure gap of 200 μm and an exposure temperature of 100 mJ / cm². 2 Illuminance of ultra-high pressure mercury lamp at 365nm: 20mW / cm² 2Then, the substrate was developed with a 0.3% sodium carbonate aqueous solution for 60 seconds and heated at 120°C for 30 minutes to produce a substrate with a cured film thickness of 2.0 μm. The through-hole pattern formed on the developed substrate was observed using a laser microscope. The patterning development characteristics were evaluated according to the following evaluation criteria, and a grade B or above was considered acceptable.

[0232] (Evaluation Criteria)

[0233] A: Through-holes are formed when the mask size is less than 15μm.

[0234] B: Through-holes are formed when the mask size is 15μm or larger but less than 30μm.

[0235] C: When the mask size is 30μm or larger, a through hole or no opening is formed.

[0236]

[0237]

[0238] As shown in Table 4, the photocurability, pencil hardness, pore-forming properties, and stability of the photosensitive resin compositions of Examples 1 to 17 of this disclosure are all good. Example 17 received a pencil hardness rating of "B", but other evaluation items were good, resulting in an overall good assessment.

[0239] On the other hand, the copolymer containing a copolymer (copolymer A'-1) whose side chains do not have a chemical structure containing alkoxysilyl groups (copolymer A'-1), as a copolymer constituting the photosensitive resin composition in Comparative Example 1, has slightly insufficient photocurability and pore-forming properties, and its pencil hardness is insufficient. The copolymer containing a copolymer (copolymer A'-2) whose side chains do not have a chemical structure "with hydroxyl groups other than alkoxysilyl groups at the ends that can be generated by acid dissociation" (copolymer A'-2), as a copolymer constituting the photosensitive resin composition in Comparative Example 2, has insufficient photocurability, and no coating film capable of measuring pencil hardness and pore-forming properties was obtained. The copolymer containing a copolymer (copolymer A'-3) whose side chains do not have a chemical structure "with hydroxyl groups other than alkoxysilyl groups at the ends that can be generated by acid dissociation" and has unprotected hydroxyl groups (copolymer A'-3), as a copolymer constituting the photosensitive resin composition in Comparative Example 3, has insufficient pore-forming properties.

[0240] Industrial availability

[0241] The copolymer and photosensitive resin composition disclosed herein is suitable as a raw material for optical spacers, spacer materials, lens materials, interlayer insulating film materials, protective film materials, optical waveguide materials, or planarization film materials.

[0242] It should be understood that the embodiments disclosed herein are exemplary in all respects and are not limited in any way. The scope of the invention is defined by the scope of the patent claims and is intended to include all modifications within the meaning and scope equivalent to the scope of the patent claims.

Claims

1. A copolymer comprising repeating structural unit A1 represented by general formula (1) and repeating structural unit A2 represented by general formula (2), In equations (1) and (2), R 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 It is a chemical structure with a terminal group other than alkoxysilyl groups that can generate hydroxyl groups through acid dissociation.

2. The copolymer according to claim 1, wherein, The copolymer further comprises repeating structural unit A3 with acidic groups at the ends of the side chains.

3. The copolymer according to claim 2, wherein, The structural unit A3 is the structural unit shown in the following general formula (3). In equation (3), R 1 It is hydrogen or methyl, X 1 It is a single bond or a linking group with 1 to 10 carbon atoms.

4. The copolymer according to claim 1 or 2, wherein, The structural unit A2 is the structural unit shown in the following general formula (II). In equation (II), R 1 It is hydrogen or methyl, R 2 It is a (poly)oxyolefin with 2 to 4 carbon atoms, R 3 It is the chemical structure shown in the following general formula (4), R 4 It is a hydrocarbon group or phenyl group with 1 to 10 carbon atoms, R 7 It is hydrogen, a hydrocarbon group with 1 to 10 carbon atoms that can be replaced by a phenyl group, or a phenyl group. In equation (4), R 5 It is a hydrocarbon group with 1 to 10 carbon atoms, R 6 It is a hydrocarbon group with 1 to 10 carbon atoms, a phenyl group, or a cyclohexyl group.

5. The copolymer according to claim 1 or 2, wherein, The structural unit A1 is the structural unit shown in the following general formula (I). In equation (I), R 1 It is hydrogen or methyl, X 2 It is an alkylene group with 1 to 10 carbon atoms, R 8 It is an alkoxy group with 1 to 10 carbon atoms, R 9 It is a hydrocarbon group with 1 to 10 carbon atoms, and a is an integer from 1 to 3.

6. The copolymer according to claim 1 or 2, wherein, The weight-average molecular weight (Mw) of the copolymer is 3000 to 20000.

7. The copolymer according to claim 2, wherein, In the copolymer, when the molar ratio of the structural unit A1, the structural unit A2 and the structural unit A3 is set to k:l:m, k:l:m = 30~80:5~40:10~40.

8. A photosensitive resin composition comprising: Polymers comprising at least the repeating structural unit A1 shown in general formula (1) below, Polymers comprising at least the repeating structural unit A2 shown in general formula (2) below, and Photoacid generator (B) In equations (1) and (2), R 1 It is hydrogen or methyl, A 1 It has a chemical structure with an alkoxysilyl group at the end, A 2 It is a chemical structure with a terminal group other than alkoxysilyl groups that can generate hydroxyl groups through acid dissociation.

9. The photosensitive resin composition according to claim 8, wherein, It further comprises a monomer (C) having at least one of an unsaturated double bond and an alkoxysilyl group within the molecule.

10. The photosensitive resin composition according to claim 8 or 9, wherein, The polymer in the photosensitive resin composition is a copolymer comprising the repeating structural unit A1 and the repeating structural unit A2.

11. The photosensitive resin composition according to claim 10, wherein, The copolymer is a copolymer that further comprises the structural unit A3 shown in the following general formula (3). In equation (3), R 1 It is hydrogen or methyl, X 1 It is a single bond or a linking group with 1 to 10 carbon atoms.

12. The photosensitive resin composition according to claim 8 or 9, wherein, It further includes a photopolymerization initiator (D).

13. The photosensitive resin composition according to claim 8 or 9, wherein, It further includes monofunctional alcohols without carboxyl groups and N-H bonds as solvents.

14. A patterning material comprising the photosensitive resin composition of claim 8 or 9.

15. A cured product obtained from the photosensitive resin composition of claim 8 or 9.

16. The cured product according to claim 15, wherein, The cured material is an optical spacer, a spacer wall material, a lens material, an interlayer insulating film material, a protective film material, an optical waveguide material, or a planarization film material.

17. An image display device comprising the cured material of claim 15.

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