Photosensitive resin composition, cured product, and partition wall

Abstract

The purpose of the present invention is to provide a photosensitive resin composition with which it is possible to form a cured product having excellent liquid repellency even when no organic fluorine compound is included or the content of an organic fluorine compound is low.　A photosensitive resin composition according to the present invention contains: an alkali-soluble resin (A) that includes a repeating structural unit (a1) having a hydrophobic group, a repeating structural unit (a2) having an acid group, and a repeating structural unit (a3) having an organopolysiloxane structure, the content of the repeating structural unit (a1) being more than 10 mol% but less than 45 mol%; a photopolymerizable monomer (B) having a LogP of 2.5-6.5; and a photopolymerization initiator (C).

Description

Photosensitive resin composition, cured product, and partition wall

[0001] The present invention relates to a photosensitive resin composition capable of forming a cured product having liquid repellency.

[0002] Conventionally, photosensitive resin compositions (resist compositions) have been used as materials for producing masks for manufacturing circuits such as semiconductor integrated circuits (ICs) and thin film transistor (TFT) circuits for liquid crystal displays (LCDs), and as materials for forming partition walls of color filters in liquid crystal display elements, partition walls of ITO (indium tin oxide) electrodes in liquid crystal display elements, partition walls of organic EL display elements, and partition walls of circuit wiring boards. In recent years, photosensitive resin compositions have also been used as materials for forming flow channels in microchannel chips, and the range of application of this technology is becoming increasingly wider.

[0003] For example, in the manufacture of color filters for liquid crystal display elements, an inkjet method is employed in which inks of each color, RGB, are sprayed onto R (red), G (green), and B (blue) pixels of several tens to several hundreds of μm each separated by a partition (black matrix). A pixel pattern consisting of a large number of pixels is formed by photolithography using a photosensitive resin composition.

[0004] In the manufacture of ITO electrodes for liquid crystal display elements, for example, an inkjet method is employed in which an ITO solution is spray-applied between partition walls when forming an ITO electrode pattern. The ITO electrode pattern, which is composed of a large number of ITO electrodes, is formed by photolithography using a photosensitive resin composition.

[0005] In the manufacture of organic EL display elements, for example, when forming a hole transport layer or a light emitting layer within a pixel (between partition walls), an inkjet method is employed in which a solution of a hole transport material or a light emitting material is spray-applied, and a pixel pattern is formed by photolithography using a photosensitive resin composition.

[0006] In the manufacture of circuit wiring boards, for example, an inkjet method is employed in which a metal solution is sprayed and applied between circuit wiring patterns formed by partition walls when forming circuit wiring, and the circuit wiring pattern is formed by photolithography using a photosensitive resin composition.

[0007] In the inkjet method, it is necessary to prevent ink from mixing between adjacent pixel regions and to prevent the ITO solution, metal solution, etc. from adhering to areas other than the predetermined regions, and therefore the partition walls are required to have a property of repelling aqueous solvents, organic solvents, etc., which are inkjet coating liquids, i.e., liquid repellency.

[0008] The channels of microchannel chips are minute channels (patterns) formed by partition walls, and a new technology has emerged that uses photolithography with a photosensitive resin composition to form the partition walls that make up these channels.

[0009] As a method for imparting liquid repellency to the partition walls, it has been proposed to blend an organic fluorine compound into a photosensitive resin composition.

[0010] For example, Patent Document 1 proposes a resist composition containing a fluorine-containing resin (A) having a fluorine atom content of 7 to 35 mass %.

[0011] Japanese Patent Application Laid-Open No. 2005-315984

[0012] Since organic fluorine compounds such as fluorine-containing resins may have adverse effects on the human body and the environment, their use has been restricted by regulations in recent years. Therefore, there is a demand for the development of a photosensitive resin composition that can form a cured product (e.g., partition wall) having sufficient liquid repellency even when it does not contain an organic fluorine compound or when the content of the organic fluorine compound is small.

[0013] The present invention has been made in view of the above problems, and aims to provide a photosensitive resin composition that can form a cured product having excellent liquid repellency even when it does not contain an organic fluorine compound or when the content of the organic fluorine compound is small.

[0014] The present invention provides the following aspects. Item 1. A photosensitive resin composition containing: an alkali-soluble resin (A) comprising a repeating structural unit (a1) having a hydrophobic group, a repeating structural unit (a2) having an acid group, and a repeating structural unit (a3) ​​having an organopolysiloxane structure, wherein the content of the repeating structural unit (a1) is more than 10 mol % and less than 45 mol %; a photopolymerizable monomer (B) having a Log P of 2.5 to 6.5; and a photopolymerization initiator (C). Item 2. The photosensitive resin composition according to Item 1, wherein the hydrophobic group of the repeating structural unit (a1) is an aromatic hydrocarbon group, an alicyclic saturated hydrocarbon group, an alicyclic unsaturated hydrocarbon group, or a group in which two or more of these groups are bonded. Item 3. The photosensitive resin composition according to Item 1 or 2, wherein the alkali-soluble resin (A) has an acid value of 40 to 100 mgKOH / g. Item 4. Item 5. The photosensitive resin composition according to any one of Items 1 to 3, wherein the alkali-soluble resin (A) further comprises a repeating structural unit (a4) having a crosslinkable functional group. Item 6. The photosensitive resin composition according to any one of Items 1 to 5, wherein the photopolymerizable monomer (B) has a functional group containing one or more ethylenically unsaturated double bonds and a ring structure, and the functional group is bonded to the ring structure directly or via a linking group. Item 7. The photosensitive resin composition according to any one of Items 1 to 5, wherein the photopolymerizable monomer (B) has a double bond equivalent of 90 to 400. Item 8. A cured product obtained from the photosensitive resin composition according to any one of Items 1 to 6. Item 9. The cured product according to Item 7, wherein the cured product is a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an optical waveguide, or a planarizing film.

[0015] The photosensitive resin composition of the present invention is characterized by containing an alkali-soluble resin (A) containing a repeating structural unit (a1) having a hydrophobic group, a repeating structural unit (a2) having an acid group, and a repeating structural unit (a3) ​​having an organopolysiloxane structure, the content of the repeating structural unit (a1) being more than 10 mol% but less than 45 mol%, and a photopolymerizable monomer (B) having a Log P of 2.5 to 6.5. By using these two components, a cured product with excellent liquid repellency can be formed even when the composition does not contain an organic fluorine compound or when the content of the organic fluorine compound is low. The photosensitive resin composition of the present invention also has the advantage of having good pattern-forming properties. Because of these characteristics, the photosensitive resin composition of the present invention is suitable for use as a molding material for photospacers, partition walls, lenses, interlayer insulating films, protective films, optical waveguides, or planarizing films.

[0016] In the present invention, (meth)acrylate means acrylate and / or methacrylate, (meth)acrylic means acrylic and / or methacrylic, (meth)acryloyl means acryloyl and / or methacryloyl, and (meth)acrylic acid means acrylic acid and / or methacrylic acid.

[0017] In the present invention, LogP is an index representing the hydrophobicity of a chemical substance, and is a value obtained by calculation using ChemDraw Professional 21.0.0 from PerkinElmer.

[0018] In the present invention, the double bond equivalent refers to the number of grams of a target compound per mole of a functional group containing an ethylenically unsaturated double bond (hereinafter also referred to as a "radically polymerizable functional group"), and is a value calculated by double bond equivalent = (amount (g) of target compound / number (mol) of radically polymerizable functional groups contained in the target compound).

[0019] In the present invention, the acid value represents the mass (mg) of potassium hydroxide required to neutralize the acid groups contained in 1 g of the target compound, and is a theoretical value calculated from the molecular weight based on the structure of the target compound and the number of functional groups (number of acid groups) per molecule. Specifically, the acid value of the target compound is a value calculated by [number of moles of acid groups of the target compound (mmol)] × [56.11 / amount of the target compound (g)].

[0020] The target compounds for the double bond equivalent and acid value include an alkali-soluble resin (A) and a photopolymerizable monomer (B). The structure, double bond equivalent, and acid value of the target compounds, as well as the content of the target compounds in the photosensitive resin composition, may be determined by analyzing the photosensitive resin composition by a known method, or may be determined from the structure and ratio of the raw materials used in producing the photosensitive resin composition.

[0021] 1. Photosensitive Resin Composition The photosensitive resin composition of the present invention is characterized by containing an alkali-soluble resin (A) that contains a repeating structural unit (a1) having a hydrophobic group, a repeating structural unit (a2) having an acid group, and a repeating structural unit (a3) ​​having an organopolysiloxane structure, wherein the content of the repeating structural unit (a1) is more than 10 mol% and less than 45 mol%, a photopolymerizable monomer (B) having a Log P of 2.5 to 6.5, and a photopolymerization initiator (C). The photosensitive resin composition of the present invention is also characterized by being substantially free of organic fluorine compounds (i.e., no organic fluorine compounds are intentionally blended), or by having a reduced content of organic fluorine compounds compared to conventional compositions.

[0022] Without being bound by theory, the reason why a cured product with excellent liquid repellency can be obtained from the photosensitive resin composition of the present invention is thought to be as follows. The inventors have found that when only a relatively hydrophobic photopolymerizable monomer is used to improve the liquid repellency of the cured product (when the alkali-soluble resin does not have a structural unit having a hydrophobic group), the liquid repellency is improved, but the patterning properties (particularly developability) of the cured product tend to deteriorate. Specifically, it is thought that if a relatively hydrophobic photopolymerizable monomer is directly contained in the composition, the monomer itself has low alkali solubility, resulting in the generation of residues and the deterioration of patterning properties. Furthermore, by incorporating both a structural unit having an acid group and a structural unit derived from a relatively hydrophobic photopolymerizable monomer in the polymer, and increasing the content of the relatively hydrophobic component in the entire composition (the repeating structural unit (a1) having a hydrophobic group in the alkali-soluble resin (A) of the present invention and the photopolymerizable monomer (B)), while ensuring that the composition contains a certain proportion of the highly alkali-soluble component (the repeating structural unit (a2) having an acid group in the alkali-soluble resin (A) of the present invention), the content of the relatively hydrophobic photopolymerizable monomer can be reduced in the uncured portion, thereby suppressing the generation of residues. On the other hand, the cured portion can contain a large amount of the relatively hydrophobic component, and further, since the alkali-soluble resin (A) contains the repeating structural unit (a3) ​​having an organopolysiloxane structure, it is thought that extremely high liquid repellency can be exhibited.

[0023]

[0023] The photosensitive resin composition of the present invention may include an organic fluorine compound as a structural unit constituting an alkali-soluble resin, or an organic fluorine compound contained in the composition (i.e., as a monomer or additive). In either embodiment, the content of the organic fluorine compound in the photosensitive resin composition of the present invention is preferably as low as possible within a range that can solve the problems of the present invention. For example, the content of the organic fluorine compound may be 10% by mass or less, 5% by mass or less, or 1% by mass or less, based on the total solid content of the photosensitive resin composition, and is preferably below the detection limit. The photosensitive resin composition of the present invention will be described in detail below.

[0024] [Alkali-Soluble Resin (A)] The alkali-soluble resin (A) comprises a repeating structural unit (a1) having a hydrophobic group, a repeating structural unit (a2) having an acid group, and a repeating structural unit (a3) ​​having an organopolysiloxane structure, and the content of the repeating structural unit (a1) is more than 10 mol % and less than 45 mol %.

[0025] <Repeating structural unit (a1) having a hydrophobic group> The monomer (a1′) forming the repeating structural unit (a1) having a hydrophobic group is not particularly limited as long as it has a radically polymerizable functional group and a hydrophobic group.

[0026] The radical polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. From the viewpoint of polymerizability with a monomer that forms another structural unit, a (meth)acryloyloxy group is preferred. The monomer (a1') may have one radical polymerizable functional group, or may have two or more of the same or different radical polymerizable substituents, but from the viewpoint of imparting good developability to the photosensitive resin composition (hereinafter simply referred to as "from the viewpoint of developability"), it is preferred that the monomer (a1') has one radical polymerizable functional group.

[0027] The hydrophobic group may be any group that provides the LogP value of the monomer (a1') of 2.0 to 4.0, but is preferably an aromatic hydrocarbon group, an alicyclic saturated hydrocarbon group, an alicyclic unsaturated hydrocarbon group, or a group formed by bonding two or more of these. Examples of aromatic hydrocarbon groups include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a fluorene ring, an acenaphthylene ring, an acenaphthene ring, and aromatic rings formed by bonding two or more of these, with a benzene ring being preferred. The aromatic hydrocarbon group may have a substituent such as an alkyl group, an alkenyl group, an alkoxy group, or a halogen group. Examples of alicyclic saturated hydrocarbon groups and alicyclic unsaturated hydrocarbon groups include those having 6 to 20 carbon atoms in the ring. From the viewpoint of developability, the ring is preferably one having 6 to 12 carbon atoms, and more preferably one having 6 to 10 carbon atoms, and may be a bridged ring, a fused ring, a spiro ring, or an alicyclic ring formed by bonding two or more of these. The alicyclic saturated hydrocarbon group and the alicyclic unsaturated hydrocarbon group may have a substituent such as an alkyl group, an alkenyl group, an alkoxy group, a halogen group, etc. Examples of the alicyclic saturated hydrocarbon group and the alicyclic unsaturated hydrocarbon group include the following groups.

[0028] The monomer (a1') may have one hydrophobic group, or may have two or more hydrophobic groups of the same type or different types, but from the viewpoint of developability, it preferably has one hydrophobic group.

[0029] The radically polymerizable functional group and the hydrophobic group may be bonded directly or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched saturated or unsaturated aliphatic hydrocarbon groups, and organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.). The hydrocarbon group and the organic group may have various substituents (e.g., halogen groups, alkyl groups, alkenyl groups, alkoxy groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.). From the viewpoint of developability, the linking group is preferably a linear or branched saturated or unsaturated aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an organic group in which some of the carbon atoms constituting the hydrocarbon group are substituted with oxygen atoms.

[0030] Examples of the monomer (a1') include the following monomers: Furthermore, the following monomers may be monomers having an acryloyloxy group instead of a methacryloyloxy group.

[0031] In the alkali-soluble resin (A), the content of the repeating structural unit (a1) is more than 10 mol % and less than 45 mol %, preferably 10 to 40 mol %, more preferably 15 to 40 mol %, and even more preferably 15 to 35 mol %, from the viewpoint of imparting excellent liquid repellency to a cured product of the photosensitive resin composition and from the viewpoint of forming a good pattern.

[0032] The alkali-soluble resin (A) may contain one type of repeating structural unit (a1), or two or more types of repeating structural units (a1).

[0033] <Repeating Structural Unit (a2) Having an Acid Group> The monomer (a2') forming the repeating structural unit (a2) having an acid group is not particularly limited as long as it has a radically polymerizable functional group and an acid group.

[0034] The radical polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. From the viewpoint of polymerizability with a monomer that forms another structural unit, a (meth)acryloyloxy group is preferred. The monomer (a2') may have one radical polymerizable functional group, or may have two or more of the same or different radical polymerizable substituents, but from the viewpoint of developability, it is preferred that the monomer (a2') has one radical polymerizable functional group.

[0035] The acid group is not particularly limited, and examples thereof include a carboxylic acid group, a sulfonic acid group, and a phosphoric acid group, but from the viewpoint of the productivity of the alkali-soluble resin (A), a carboxylic acid group is preferred. The monomer (a2') may have one acid group or two or more acid groups of the same type or different types, but from the viewpoint of developability, it is preferred that the monomer (a2') have one acid group.

[0036] The radically polymerizable functional group and the acid group may be bonded directly or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched saturated or unsaturated aliphatic hydrocarbon groups, and organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.). The hydrocarbon group and the organic group may have various substituents (e.g., halogen groups, alkyl groups, alkenyl groups, alkoxy groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.). From the viewpoint of developability, the linking group is preferably a linear or branched saturated or unsaturated aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an organic group in which some of the carbon atoms constituting the hydrocarbon group are substituted with oxygen atoms.

[0037] Examples of the monomer (a2') include carboxy group-containing monomers such as (meth)acrylic acid, 2-(meth)acryloyloxyethyl succinic acid, maleic acid, and itaconic acid, with (meth)acrylic acid being preferred.

[0038] In the alkali-soluble resin (A), the content of the repeating structural unit (a2) is not particularly limited, but from the viewpoint of imparting excellent liquid repellency to a cured product of the photosensitive resin composition and from the viewpoint of alkali developability of the photosensitive resin composition, it is preferably 1 to 50 mol %, more preferably 5 to 40 mol %, even more preferably 10 to 35 mol %, and still more preferably 15 to 30 mol %.

[0039] The alkali-soluble resin (A) may contain one type of repeating structural unit (a2), or two or more types of repeating structural units (a2).

[0040] <Repeating structural unit (a3) ​​having an organopolysiloxane structure> The monomer (a3′) that forms the repeating structural unit (a3) ​​having an organopolysiloxane structure is not particularly limited as long as it has a radically polymerizable functional group and an organopolysiloxane structure in one molecule.

[0041] The radical polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group, and from the viewpoint of polymerizability with a monomer that forms another structural unit, a (meth)acryloyloxy group is preferred. The monomer (a3') may have one radical polymerizable functional group, or may have two or more of the same or different radical polymerizable substituents, but from the viewpoint of developability, it is preferred to have one radical polymerizable functional group.

[0042] The organopolysiloxane structure is not particularly limited and may be linear, branched, cyclic, or a combination of two or more of these structures, but is preferably an organopolysiloxane structure represented by the following general formula (1): (In the formula, R 1 and R 2 are each independently an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, or an aralkyl group, and n is an integer of 0 to 1000.

[0043] Examples of the alkyl group include alkyl groups having 1 to 12 carbon atoms, such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, and an octyl group.

[0044] Examples of the cycloalkyl group include cycloalkyl groups having 4 to 10 carbon atoms, such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group.

[0045] Examples of the alkenyl group include a vinyl group and an allyl group.

[0046] Examples of the aryl group include a phenyl group, a tolyl group, a biphenyl group, and a naphthyl group. From the viewpoint of imparting excellent liquid repellency to the cured product of the photosensitive resin composition and from the viewpoint of forming a good pattern, a phenyl group is preferred.

[0047] Examples of the aralkyl group include a benzyl group and a phenethyl group.

[0048] n is an integer of 0 to 1000, and from the viewpoint of imparting excellent liquid repellency to a cured product of the photosensitive resin composition and of forming a good pattern, n is preferably an integer of 1 to 500, more preferably an integer of 1 to 300, and even more preferably an integer of 1 to 200.

[0049] In the general formula (1), from the viewpoint of imparting excellent liquid repellency to the cured product of the photosensitive resin composition and from the viewpoint of forming a good pattern, R 1 and R 2 is an alkyl group, and more preferably R 1 is an alkyl group having 1 to 4 carbon atoms, R 2 is an alkyl group having 1 to 8 carbon atoms, and more preferably R 1 is a methyl group or an ethyl group, R 2 is an alkyl group having 1 to 4 carbon atoms, and particularly preferably R 1 is a methyl group, R 2 is a butyl group.

[0050] The weight-average molecular weight (MW) of the organopolysiloxane in the organopolysiloxane structure is not particularly limited, but from the viewpoint of imparting excellent liquid repellency to the cured product of the photosensitive resin composition and from the viewpoint of forming a good pattern, it is preferably 300 to 30,000, more preferably 1,000 to 20,000, and even more preferably 1,000 to 10,000. The weight-average molecular weight is determined by gel permeation chromatography (GPC) in accordance with JIS K 7252-1:2016 and is a value converted using standard polystyrene.

[0051] The radically polymerizable functional group and the organopolysiloxane structure may be bonded directly or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched saturated or unsaturated aliphatic hydrocarbon groups, and organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.). The hydrocarbon group and the organic group may also have various substituents (e.g., halogen groups, alkyl groups, alkenyl groups, alkoxy groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.). From the viewpoint of developability, the linking group is preferably a linear or branched saturated or unsaturated aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an organic group in which some of the carbon atoms constituting the hydrocarbon group are substituted with oxygen atoms, more preferably a linear saturated aliphatic hydrocarbon group having 1 to 5 carbon atoms, and even more preferably a linear saturated aliphatic hydrocarbon group having 2 to 4 carbon atoms.

[0052] In the alkali-soluble resin (A), the content of the repeating structural unit (a3) ​​is not particularly limited, but from the viewpoint of imparting excellent liquid repellency to a cured product of the photosensitive resin composition and from the viewpoint of forming a good pattern, the content is preferably 0.001 to 2.3 mol %, more preferably 0.002 to 1.1 mol %, even more preferably 0.004 to 0.87 mol %, and still more preferably 0.005 to 0.64 mol % on a mol % basis.

[0053] The alkali-soluble resin (A) may contain one type of repeating structural unit (a3), or two or more types of repeating structural units (a3).

[0054] <Repeating structural unit (a4) having a crosslinkable functional group> From the viewpoint of obtaining a photosensitive resin composition capable of forming a cured film having a good pattern, the alkali-soluble resin (A) preferably further contains a repeating structural unit (a4) having a crosslinkable functional group. The alkali-soluble resin (A) may contain one type of repeating structural unit (a4), or two or more types of repeating structural units (a4). The crosslinkable functional group is not particularly limited as long as it is a functional group that undergoes a crosslinking reaction. Furthermore, the monomer (a4') that forms the repeating structural unit (a4) having a crosslinkable functional group is not particularly limited as long as it has a radically polymerizable functional group and a crosslinkable functional group. Examples of the repeating structural unit (a4) having a crosslinkable functional group include a repeating structural unit (a4-1) having a radically polymerizable functional group and a repeating structural unit (a4-2) having an oxygen-containing ring.

[0055] In the alkali-soluble resin (A), the content of the repeating structural unit (a4) is not particularly limited, but from the viewpoint of forming a cured film having a good pattern, it is preferably 10 to 60 mol %, more preferably 15 to 55 mol %, even more preferably 15 to 50 mol %, and still more preferably 15 to 45 mol %.

[0056] <<Repeating structural unit (a4-1) having a radical polymerizable functional group>> The monomer (a4'-1) forming the repeating structural unit (a4-1) having a radical polymerizable functional group is not particularly limited as long as it has two or more radical polymerizable functional groups in one molecule. When the alkali-soluble resin (A) is produced using the monomer (a4'-1) as a raw material, theoretically, any one of the two or more radical polymerizable functional groups will randomly constitute the main chain of the alkali-soluble resin (A), and the remaining radical polymerizable functional groups will form a crosslinked structure.

[0057] The radical polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. The monomer (a4'-1) may have one type of radical polymerizable functional group, or may have two or more types. From the viewpoint of polymerizability with monomers that form other structural units and from the viewpoint of developability, it is preferable that the monomer (a4'-1) have two (meth)acryloyloxy groups.

[0058] In the monomer (a4'-1), the radically polymerizable functional groups may be bonded directly to each other or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched aliphatic saturated or unsaturated hydrocarbon groups, and organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.). The hydrocarbon group and the organic group may have various substituents (e.g., halogen groups, alkyl groups, alkenyl groups, alkoxy groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.).

[0059] Examples of the monomer (a4'-1) include a monomer represented by the following general formula (a4''-1). (In the formula, R 3 and R 6 are each independently a hydrogen atom or a methyl group, and R 4 and R 5 are each independently a linear or branched saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group having 1 to 10 carbon atoms.

[0060] In the general formula (a4″-1), R 4 and R 5 are each independently preferably a linear or branched saturated aliphatic hydrocarbon group having 1 to 5 carbon atoms, more preferably a linear saturated aliphatic hydrocarbon group having 2 to 4 carbon atoms.

[0061] <<Repeating structural unit (a4-2) having an oxygen-containing ring>> The monomer (a4'-2) that forms the repeating structural unit (a4-2) having an oxygen-containing ring is not particularly limited as long as it has a radically polymerizable functional group and an oxygen-containing ring, is copolymerizable with other monomers, and is capable of forming a crosslinked structure by ring-opening of the oxygen-containing ring. Note that the repeating structural unit having an oxygen-containing ring is synonymous with a repeating structural unit having a cyclic ether structure.

[0062] Examples of the monomer (a4'-2) include a monomer represented by the following general formula (a4''-2). (In the formula, R 7 is a hydrogen atom or a methyl group, and R 8 is an aliphatic hydrocarbon group having a cyclic ether structure and having 3 to 15 carbon atoms, which may contain oxygen atoms other than those contained in the cyclic ether structure.

[0063] In the general formula (a4″-2), from the viewpoint of the heat resistance of the obtained cured product, R 7 is preferably a methyl group. 8 The number of carbon atoms in the aliphatic hydrocarbon group in R is preferably 3 to 7. 8 Examples of the repeating structural unit (a4-2) having an oxygen-containing ring include a group in which a cyclic ether structure is bonded to the end of an alkylene group (e.g., a methylene group). The aliphatic hydrocarbon group may have an -O- structure (a structure containing an oxygen atom: for example, an ether group (-O-), an ester group (-CO-O-), an acid anhydride group (-CO-O-CO-), etc.) in a structure other than the cyclic ether structure. Therefore, the repeating structural unit (a4-2) having an oxygen-containing ring can be a repeating structural unit derived from an epoxy group-containing (meth)acrylate and an oxetane group-containing (meth)acrylate.

[0064] Examples of the monomer represented by the general formula (a4''-2) include the following monomers.

[0065] In the alkali-soluble resin (A), the content of the repeating structural unit (a4-2) having an oxygen-containing ring is not particularly limited, but from the viewpoint of forming a cured film having a good pattern, it is preferably 5 to 35 mol %, more preferably 10 to 30 mol %, and even more preferably 20 to 30 mol %.

[0066] <Repeating structural units derived from copolymerized monomers (other structural units)> The alkali-soluble resin (A) may contain a repeating structural unit (a5) derived from a copolymerizable monomer (a5') such as an alkyl (meth)acrylate, such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate, and stearyl (meth)acrylate; a hydroxyl group-containing (meth)acrylate, such as 2-hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate; an alkoxy group-containing (meth)acrylate, such as ethoxyethyl (meth)acrylate; an epoxy group-containing (meth)acrylate, such as (3,4-epoxycyclohexyl)methyl (meth)acrylate and glycidyl (meth)acrylate; or a maleimide, such as cyclohexylmaleimide, phenylmaleimide, methylmaleimide, ethylmaleimide, n-butylmaleimide, and laurylmaleimide, within the range that does not impair the effects of the present invention. These repeating structural units (a5) may be contained alone or in combination of two or more. From the viewpoint of developability, the alkali-soluble resin (A) preferably contains a repeating structural unit derived from a hydroxyl group-containing (meth)acrylate. In the alkali-soluble resin (A), the content of the repeating structural unit derived from a hydroxyl group-containing (meth)acrylate is preferably 35 mol% or less, more preferably 25 mol% or less, and even more preferably 10 mol% or less.

[0067] <Other Components> The weight average molecular weight (MW) of the alkali-soluble resin (A) is not particularly limited, but when the photosensitive resin composition is used as a resist material, from the viewpoint of obtaining good exposure sensitivity and good developability, it is preferably 3,000 to 100,000, more preferably 5,000 to 50,000, and even more preferably 8,000 to 20,000. The weight average molecular weight is determined by gel permeation chromatography (GPC) in accordance with JIS K 7252-1:2016 and is a value converted using standard polystyrene.

[0068] The acid value of the alkali-soluble resin (A) is not particularly limited, but from the viewpoint of imparting good developability to the photosensitive resin composition, it is preferably 40 to 100 mgKOH / g, more preferably 50 mgKOH / g or more but less than 90 mgKOH / g, and even more preferably 60 to 85 mgKOH / g.

[0069] When the alkali-soluble resin (A) has a radically polymerizable functional group, the double bond equivalent of the alkali-soluble resin (A) is not particularly limited, but from the viewpoint of forming a cured film having a good pattern, it is preferably 300 to 2,000, more preferably 350 to 1,500, and even more preferably 400 to 1,200.

[0070] The alkali-soluble resin (A) can be produced by a known method, for example, by radical polymerization of a monomer composition essentially containing the monomer (a1'), the monomer (a2'), and the monomer (a3'), and optionally containing the monomer (a4') and / or the copolymerizable monomer (a5'). Note that each repeating structural unit may be formed by radical polymerization of a monomer composition containing a precursor monomer that serves as a precursor of each structural unit, and then performing a substitution / addition reaction on the repeating structural unit derived from the precursor monomer. Specifically, a first resin solution containing a first resin is produced by radically polymerizing a monomer composition containing the monomer (a1'), the monomer (a2'), the monomer (a3'), and the monomer (a4'-1A), which is a precursor of the monomer (a4'-1), and then a reactant (a4'-1B) is added to the first resin solution, and the reactant (a4'-1B) is reacted with all or a portion of the structural units derived from the monomer (a4'-1A), thereby forming the repeating structural unit (a4-1). Note that when the repeating structural unit (a4-1) is derived from the monomer (a4'-1A) and the reactant (a4'-1B), depending on the ratio of these when synthesizing the alkali-soluble resin (A), the alkali-soluble resin (A) may contain a repeating structural unit corresponding to the monomer (a4'-1A), but this repeating structural unit is treated as the other structural unit.

[0071] The alkali-soluble resin (A) may be a random copolymer, block copolymer, alternating copolymer, or periodic copolymer containing the repeating structural unit (a1), the repeating structural unit (a2), and the repeating structural unit (a3). The alkali-soluble resin (A) may also be a random copolymer, block copolymer, alternating copolymer, or periodic copolymer containing, in addition to the repeating structural units (a1) to (a3), the repeating structural unit (a4) and / or the repeating structural unit (a5) derived from the copolymerizable monomer.

[0072] In the photosensitive resin composition, the content of the alkali-soluble resin (A) is usually about 20 to 90 mass % based on the total solid content of the photosensitive resin composition, and from the viewpoint of further improving the effects of the present invention, it is preferably 30 to 85 mass %, more preferably 40 to 80 mass %, and even more preferably 45 to 80 mass %.

[0073] [Photopolymerizable Monomer (B)] The photopolymerizable monomer (B) is not particularly limited as long as it has a LogP of 2.5 to 6.5.

[0074] The Log P of the photopolymerizable monomer (B) is preferably 2.8 to 6.5, more preferably 3.0 to 6.5, from the viewpoint of imparting excellent liquid repellency to a cured product of the photosensitive resin composition, and from the viewpoint of obtaining good exposure sensitivity and good developability when the photosensitive resin composition is used as a resist material.

[0075] The photopolymerizable monomer (B) preferably has one or more radically polymerizable functional groups and a ring structure in its molecule, from the viewpoint of imparting excellent liquid repellency to the cured product of the photosensitive resin composition and from the viewpoint of obtaining good exposure sensitivity and good developability when the photosensitive resin composition is used as a resist material. The radically polymerizable functional group is preferably bonded to the ring structure directly or via a linking group. The radically polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. From the viewpoint described above, the radically polymerizable functional group is preferably a (meth)acryloyl group or a (meth)acryloyloxy group. The photopolymerizable monomer (B) may have one radically polymerizable functional group, or may have two or more radically polymerizable substituents of the same or different types. From the viewpoint of improving the adhesion of the cured product, the number of radically polymerizable functional groups is preferably 1 to 6, more preferably 1 to 4, and even more preferably 1 or 2.

[0076] The ring structure is not particularly limited, and examples thereof include aromatic hydrocarbon groups, alicyclic saturated hydrocarbon groups, alicyclic unsaturated hydrocarbon groups, heterocycles in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms, and organic groups in which two or more of these are bonded directly or via a linking group (e.g., a linear or branched aliphatic saturated hydrocarbon group or aliphatic unsaturated hydrocarbon group, a heteroatom, a group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms, etc.). Examples of the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a fluorene ring, an acenaphthylene ring, and an acenaphthene ring. The aromatic hydrocarbon group may have a substituent such as an alkyl group, an alkenyl group, an alkoxy group, or a halogen group. Examples of the alicyclic saturated hydrocarbon group and alicyclic unsaturated hydrocarbon group include those having 6 to 20 carbon atoms constituting the ring, preferably those having 6 to 12 carbon atoms constituting the ring, and more preferably those having 6 to 10 carbon atoms constituting the ring. They may be bridged rings, fused rings, spiro rings, or polycyclic rings formed by bonding two or more of these. The alicyclic saturated hydrocarbon group and alicyclic unsaturated hydrocarbon group may have a substituent such as an alkyl group, an alkenyl group, an alkoxy group, or a halogen group. Examples of the heteroatom include an oxygen atom, a nitrogen atom, and a sulfur atom. The heterocycle may contain one or more types of heteroatoms, or may contain one or more heteroatoms.

[0077] When the radical polymerizable functional group is bonded to the ring structure via a linking group, the linking group is not particularly limited and may be, for example, a linear or branched saturated aliphatic hydrocarbon group or an aliphatic unsaturated hydrocarbon group, or an organic group in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.). The hydrocarbon group and the organic group may have various substituents (e.g., halogen groups, alkyl groups, alkenyl groups, alkoxy groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.). From the viewpoint of developability, the linking group is preferably a linear or branched saturated aliphatic hydrocarbon group or an aliphatic unsaturated hydrocarbon group having 1 to 10 carbon atoms, or an organic group in which some of the carbon atoms constituting the hydrocarbon group are substituted with oxygen atoms.

[0078] Examples of the photopolymerizable monomer (B) include the following monomers: Furthermore, the following monomers may be monomers having a methacryloyloxy group instead of an acryloyloxy group.

[0079] The double bond equivalent of the photopolymerizable monomer (B) is preferably 90 to 400, more preferably 95 to 395, and even more preferably 100 to 390, from the viewpoint of imparting excellent liquid repellency to the cured product of the photosensitive resin composition.

[0080] In the photosensitive resin composition, the content of the photopolymerizable monomer (B) is usually about 5 to 80 mass % based on the total solid content of the photosensitive resin composition, and from the viewpoint of further improving the effects of the present invention, it is preferably 10 to 70 mass %, more preferably 20 to 60 mass %, and even more preferably 20 to 55 mass %.

[0081] In the photosensitive resin composition, the mass ratio of the photopolymerizable monomer (B) to the alkali-soluble resin (A) [(B) / (A)] is preferably 0.1 to 2.0, more preferably 0.2 to 1.7, even more preferably 0.3 to 1.5, and still more preferably 0.3 to 1.2, from the viewpoint of further improving the effects of the present invention.

[0082] [Photopolymerization initiator (C)] The photopolymerization initiator (C) is not particularly limited, and examples thereof include benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-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-propan-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides, and xanthones. These photopolymerization initiators may be used alone or in combination of two or more.

[0083] In the photosensitive resin composition, the content of the photopolymerization initiator (C) is not particularly limited, but is preferably 0.1 to 10 mass%, more preferably 0.2 to 8 mass%, and even more preferably 0.3 to 5 mass%, when the total solid content of the photosensitive resin composition is taken as 100 mass%.

[0084] [Optional Components] The photosensitive resin composition may contain a polymerizable monomer other than the photopolymerizable monomer (B) within a range that does not impair the effects of the present invention. Examples of the polymerizable monomer include monofunctional monomers such as nonylphenylcarbitol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-ethylhexylcarbitol (meth)acrylate, N-vinylpyrrolidone, and ethoxylated-o-phenylphenol (meth)acrylate; polyfunctional aromatic vinyl monomers such as divinylbenzene, diallyl phthalate, and diallylbenzene phosphonate; (di)ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, bisphenol A ethylene oxide adduct di(meth)acrylate, and trimethylolpropane. Examples of the polymerizable monomer include polyfunctional (meth)acrylates such as tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and tris(hydroxyethyl)isocyanurate tri(meth)acrylate; and polyfunctional epoxy monomers such as bisphenol diglycidyl ether, phthalic acid diglycidyl ester, 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, and triglycidyl isocyanurate. These polymerizable monomers may be used alone or in combination of two or more.

[0085] The photosensitive resin composition may contain a known alkali-soluble resin other than the alkali-soluble resin (A) of the present invention; a radical-polymerizable oligomer such as an unsaturated polyester, an epoxy acrylate, a urethane acrylate, or a polyester acrylate; or a curable resin such as an epoxy resin, within a range that does not impair the effects of the present invention.

[0086] The photosensitive resin composition may contain a photopolymerization initiation aid. Examples of the photopolymerization initiation aid include trifunctional thiol compounds such as 1,3,5-tris(3-mercaptopropionyloxyethyl)isocyanurate, 1,3,5-tris(3-mercaptobutyloxyethyl)isocyanurate (manufactured by Showa Denko K.K., Karenz MT (registered trademark) NR1), and trimethylolpropane tris(3-mercaptopropionate); tetrafunctional thiol compounds such as pentaerythritol tetrakis(3-mercaptopropionate) and pentaerythritol tetrakis(3-mercaptobutyrate) (manufactured by Showa Denko K.K., Karenz MT (registered trademark) PEI); and polyfunctional thiols such as hexafunctional thiol compounds such as dipentaerythritol hexakis(3-propionate). These photopolymerization initiation aids may be used alone or in combination of two or more.

[0087] The photosensitive resin composition may contain a thermal polymerization initiator. Examples of the thermal polymerization initiator include organic peroxides such as cumene hydroperoxide, diisopropylbenzene peroxide, di-t-butyl peroxide, lauryl peroxide, benzoyl peroxide, t-butylperoxyisopropyl carbonate, t-butylperoxy-2-ethylhexanoate, and t-amylperoxy-2-ethylhexanoate; and azo compounds such as 2,2'-azobis(isobutyronitrile), 1,1'-azobis(cyclohexanecarbonitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), and dimethyl 2,2'-azobis(2-methylpropionate). These thermal polymerization initiators may be used alone or in combination of two or more.

[0088] The photosensitive resin composition may contain a solvent. Examples of the solvent 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; chloroform, dimethyl sulfoxide, and the like. These solvents may be used alone or in combination of two or more. The content of the solvent may be appropriately determined depending on the optimal viscosity of the curable resin composition when used.

[0089] The photosensitive resin composition may contain known additives such as fillers such as aluminum hydroxide, talc, clay, and barium sulfate, crosslinking agents, surfactants (e.g., silicone-based surfactants), dyes, pigments, antifoaming agents, coupling agents, leveling agents, sensitizers, release agents, lubricants, plasticizers, antioxidants, ultraviolet absorbers, flame retardants, polymerization inhibitors, thickeners, and dispersants, as long as the effects of the present invention are not impaired.

[0090] 2. Cured Product The cured product of the present invention is obtained by curing the photosensitive resin composition and has excellent liquid repellency, particularly water repellency. Examples of methods for producing the cured product include coating the photosensitive resin composition onto a substrate or various functional layers to form a desired shape, and then irradiating the photosensitive resin composition with light (e.g., ultraviolet light) to cure the photosensitive resin composition. However, the method is not particularly limited to this method, and known methods can be used depending on the purpose and application of forming the cured product. Curing conditions are appropriately adjusted depending on the photosensitive resin composition used.

[0091] The cured product of the present invention is suitably used as a cured product having a pattern shape, such as a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an optical waveguide, and a planarizing film.

[0092] The method for forming a cured product having a pattern shape is not particularly limited. For example, the photosensitive resin composition can be applied to a substrate or various functional layers, dried to form a coating film, and then photolithography can be used. Photolithography may be either positive or negative, but negative photolithography is preferred when forming a thick film pattern. A method for forming a cured product having a pattern shape using negative photolithography involves, for example, placing a photomask on the coating film, irradiating it with ultraviolet light to photocure the coating film, spraying an alkaline aqueous solution onto the UV-irradiated coating film, dissolving and removing the unexposed areas, and washing and developing the remaining exposed areas to form a cured product having a pattern shape composed of numerous partition walls. Post-baking may then be performed.

[0093] The film thickness of the pattern formed using the photosensitive resin composition of the present invention is not particularly limited, but by using the photosensitive resin composition of the present invention, it is possible to form a relatively thick film pattern with a film thickness of 10 μm or more, 20 μm or more, 30 μm or more, or even 50 μm or more. Furthermore, the pattern formed using the photosensitive resin composition of the present invention has high adhesion to the substrate after development (high development adhesion) and can be a high-resolution pattern. The film thickness of the pattern refers to the height of the cured product portion in the pattern, and is the height of the partition walls when the cured product is used as the partition walls.

[0094] The present invention will be described below with reference to examples, but the present invention is not limited to these examples in any way.

[0095] Production Example 1 [Synthesis of Alkali-Soluble Resin (A-1)] A glass flask equipped with a heating / cooling / stirring apparatus, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 32.6 g of methacrylic acid, 88.7 g of 2-hydroxyethyl methacrylate, 1.5 g of a monomer having an organopolysiloxane structure represented by the following formula (a3'-1) (organopolysiloxane weight average molecular weight (Mw) measured by GPC (standard substance: polystyrene): 5000), and 334.2 g of propylene glycol monomethyl ether acetate (PGMEA). After the gas phase in the system was replaced with nitrogen, 11.2 g of 2,2'-azobisisobutyronitrile was added, heated to 80°C, and reacted at the same temperature for 8 hours to obtain a resin solution containing a first resin. Then, 94.0 g of 2- (acryloyloxy) ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing an alkali-soluble resin (A-1). The synthesized alkali-soluble resin (A-1) contained 29.99 mol% of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 25.00 mol% of repeating structural units (a2-1) derived from methacrylic acid, 0.02 mol% of repeating structural units (a3-1) derived from a monomer having an organopolysiloxane structure represented by the following formula (a3'-1), 43.99 mol% of repeating structural units (a4-1) represented by the following formula, and 1.00 mol% of repeating structural units (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-1) has an acid value of 67 mgKOH / g, a weight average molecular weight (Mw) of 14,000 as determined by GPC (standard substance: polystyrene), and a double bond equivalent of 476.

[0096] Production Example 2 [Synthesis of Alkali-Soluble Resin (A-2)] A glass flask equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 32.6 g of methacrylic acid, 88.6 g of 2-hydroxyethyl methacrylate, 3.0 g of a monomer having an organopolysiloxane structure represented by formula (a3'-1) (organopolysiloxane weight average molecular weight (Mw) measured by GPC (standard substance: polystyrene): 5000), and 336.3 g of propylene glycol monomethyl ether acetate (PGMEA). After the gas phase in the system was replaced with nitrogen, 11.2 g of 2,2'-azobisisobutyronitrile was added, heated to 80°C, and reacted at the same temperature for 8 hours to obtain a resin solution containing a first resin. Then, 94.0 g of 2- (acryloyloxy) ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing an alkali-soluble resin (A-1). The synthesized alkali-soluble resin (A-2) contained 29.99 mol% of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 24.99 mol% of repeating structural units (a2-1) derived from methacrylic acid, 0.04 mol% of repeating structural units (a3-1) derived from a monomer having an organopolysiloxane structure represented by the formula (a3'-1), 43.98 mol% of repeating structural units (a4-1) represented by the formula, and 1.00 mol% of repeating structural units (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-2) has an acid value of 67 mgKOH / g, a weight average molecular weight (Mw) of 14,000 as determined by GPC (standard substance: polystyrene), and a double bond equivalent of 478.

[0097] Production Example 3 [Synthesis of Alkali-Soluble Resin (A-3)] A glass flask equipped with a heating / cooling / stirring apparatus, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 32.6 g of methacrylic acid, 88.6 g of 2-hydroxyethyl methacrylate, 6.0 g of a monomer having an organopolysiloxane structure represented by formula (a3'-1) (organopolysiloxane weight average molecular weight (Mw) measured by GPC (standard substance: polystyrene): 5000), and 340.7 g of propylene glycol monomethyl ether acetate (PGMEA). After the gas phase in the system was replaced with nitrogen, 11.2 g of 2,2'-azobisisobutyronitrile was added, heated to 80°C, and reacted at the same temperature for 8 hours to obtain a resin solution containing a first resin. Then, 94.0 g of 2- (acryloyloxy) ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing an alkali-soluble resin (A-1). The synthesized alkali-soluble resin (A-3) contained 29.98 mol% of the repeating structural unit (a1-1) derived from dicyclopentanyl methacrylate, 24.98 mol% of the repeating structural unit (a2-1) derived from methacrylic acid, 0.07 mol% of the repeating structural unit (a3-1) derived from a monomer having an organopolysiloxane structure represented by the formula (a3'-1), 43.97 mol% of the repeating structural unit (a4-1) represented by the formula, and 1.00 mol% of the repeating structural unit (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-3) has an acid value of 66 mgKOH / g, a weight average molecular weight (Mw) of 14,000 as determined by GPC (standard substance: polystyrene), and a double bond equivalent of 482.

[0098] Production Example 4 [Synthesis of Alkali-Soluble Resin (A-4)] A glass flask equipped with a heating / cooling / stirring apparatus, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 32.6 g of methacrylic acid, 88.6 g of 2-hydroxyethyl methacrylate, 3.0 g of a monomer having an organopolysiloxane structure represented by formula (a3'-1) (organopolysiloxane weight average molecular weight (Mw) measured by GPC (standard substance: polystyrene): 10,000), and 336.3 g of propylene glycol monomethyl ether acetate (PGMEA). After the gas phase in the system was replaced with nitrogen, 11.2 g of 2,2'-azobisisobutyronitrile was added, heated to 80°C, and reacted at the same temperature for 8 hours to obtain a resin solution containing a first resin. Then, 94.0 g of 2- (acryloyloxy) ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing an alkali-soluble resin (A-1). The synthesized alkali-soluble resin (A-4) contained 29.99 mol% of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 25.00 mol% of repeating structural units (a2-1) derived from methacrylic acid, 0.02 mol% of repeating structural units (a3-1) derived from a monomer having an organopolysiloxane structure represented by the formula (a3'-1), 43.99 mol% of repeating structural units (a4-1) represented by the formula, and 1.00 mol% of repeating structural units (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-4) has an acid value of 67 mgKOH / g, a weight average molecular weight (Mw) of 14,000 as determined by GPC (standard substance: polystyrene), and a double bond equivalent of 478.

[0099] Production Example 5 [Synthesis of Alkali-Soluble Resin (A-5)] A glass flask equipped with a heating / cooling / stirring apparatus, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 32.6 g of methacrylic acid, 88.6 g of 2-hydroxyethyl methacrylate, 6.0 g of a monomer having an organopolysiloxane structure represented by formula (a3'-1) (organopolysiloxane weight average molecular weight (Mw) measured by GPC (standard substance: polystyrene): 1000), and 340.7 g of propylene glycol monomethyl ether acetate (PGMEA). After the gas phase in the system was replaced with nitrogen, 11.2 g of 2,2'-azobisisobutyronitrile was added, heated to 80°C, and reacted at the same temperature for 8 hours to obtain a resin solution containing a first resin. Then, 94.0 g of 2- (acryloyloxy) ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing an alkali-soluble resin (A-1). The synthesized alkali-soluble resin (A-5) contained 29.89 mol% of the repeating structural unit (a1-1) derived from dicyclopentanyl methacrylate, 24.91 mol% of the repeating structural unit (a2-1) derived from methacrylic acid, 0.37 mol% of the repeating structural unit (a3-1) derived from a monomer having an organopolysiloxane structure represented by the formula (a3'-1), 43.83 mol% of the repeating structural unit (a4-1) represented by the formula, and 1.00 mol% of the repeating structural unit (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-5) has an acid value of 66 mgKOH / g, a weight average molecular weight (Mw) of 14,000 as determined by GPC (standard substance: polystyrene), and a double bond equivalent of 482.

[0100] Production Example 6 [Synthesis of Alkali-Soluble Resin (A-6)] A glass flask equipped with a heating / cooling stirrer, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 46.9 g of methacrylic acid, 21.1 g of a monomer having an organopolysiloxane structure represented by formula (a3'-1) (weight average molecular weight (Mw) of the organopolysiloxane measured by GPC (standard substance: polystyrene): 5000), 127.3 g of methyl methacrylate, 148.5 g of (3,4-epoxycyclohexyl)methyl methacrylate, and 1058.5 g of cyclopentanone. The gas phase in the system was replaced with nitrogen, and then 31.1 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was added. The mixture was heated to 65°C and reacted at the same temperature for 8 hours to obtain a solution containing alkali-soluble resin (A-6). The synthesized alkali-soluble resin (A-6) contained 15.00 mol% of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 17.99 mol% of repeating structural units (a2-1) derived from methacrylic acid, 0.03 mol% of repeating structural units (a3-1) derived from a monomer having an organopolysiloxane structure represented by the formula (a3'-1), 24.99 mol% of repeating structural units (a4-2) derived from (3,4-epoxycyclohexyl)methyl methacrylate, and 41.99 mol% of repeating structural units (a5-2) derived from methyl methacrylate. The synthesized alkali-soluble resin (A-6) also had an acid value of 82 mg KOH / g and a weight average molecular weight (Mw) of 10,000 as measured by GPC (standard substance: polystyrene).

[0101] Production Example 7 [Synthesis of alkali-soluble resin (A-7)] A glass flask equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 32.6 g of methacrylic acid, 88.6 g of 2-hydroxyethyl methacrylate, and 331.8 g of propylene glycol monomethyl ether acetate (PGMEA). After replacing the gas phase in the system with nitrogen, 11.2 g of 2,2'-azobisisobutyronitrile was added, heated to 80 ° C., and reacted at the same temperature for 8 hours to obtain a resin solution containing the first resin. Then, 94.0 g of 2-(acryloyloxy)ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing alkali-soluble resin (A-7). The synthesized alkali-soluble resin (A-7) contained 30 mol % of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 25 mol % of repeating structural units (a2-1) derived from methacrylic acid, 44 mol % of repeating structural units (a4-1) represented by the above formula, and 1 mol % of repeating structural units (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-7) also had an acid value of 67 mg KOH / g, a weight-average molecular weight (Mw) of 14,000 measured by GPC (standard substance: polystyrene), and a double bond equivalent of 473.

[0102] Production Example 8 [Synthesis of alkali-soluble resin (A-8)] A glass flask equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 97.7 g of methacrylic acid, 177.2 g of 2-hydroxyethyl methacrylate, 159.1 g of methyl methacrylate, and 801.0 g of propylene glycol monomethyl ether acetate (PGMEA). After replacing the gas phase in the system with nitrogen, 33.6 g of 2,2'-azobisisobutyronitrile was added, heated to 80 ° C., and reacted at the same temperature for 8 hours to obtain a resin solution containing the first resin. Then, 128.1 g of 2-(acryloyloxy)ethyl isocyanate (AOI) and 0.02 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing alkali-soluble resin (A-8). The synthesized alkali-soluble resin (A-8) contained 10 mol % of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 25 mol % of repeating structural units (a2-1) derived from methacrylic acid, 20 mol % of repeating structural units (a4-1) represented by the above formula, 10 mol % of repeating structural units (a5-1) derived from 2-hydroxyethyl methacrylate, and 35 mol % of repeating structural units (a5-2) derived from methyl methacrylate. The synthesized alkali-soluble resin (A-8) also had an acid value of 96 mg KOH / g, a weight-average molecular weight (Mw) of 12,000 measured by GPC (standard substance: polystyrene), and a double bond equivalent of 729.

[0103] Production Example 9 [Synthesis of alkali-soluble resin (A-9)] A glass flask equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 13.0 g of methacrylic acid, 52.5 g of 2-hydroxyethyl methacrylate, and 248.3 g of propylene glycol monomethyl ether acetate (PGMEA). After replacing the gas phase in the system with nitrogen, 7.5 g of 2,2'-azobisisobutyronitrile was added, heated to 80 ° C., and reacted at the same temperature for 8 hours to obtain a resin solution containing the first resin. Then, 54.1 g of 2-(acryloyloxy)ethyl isocyanate (AOI) and 0.01 g of hydroquinone were added to the first resin solution, and the mixture was stirred thoroughly at 65 ° C. for 10 hours to obtain a solution containing alkali-soluble resin (A-9). The synthesized alkali-soluble resin (A-9) contained 45 mol % of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 15 mol % of repeating structural units (a2-1) derived from methacrylic acid, 38 mol % of repeating structural units (a4-1) represented by the above formula, and 2 mol % of repeating structural units (a5-1) derived from 2-hydroxyethyl methacrylate. The synthesized alkali-soluble resin (A-9) also had an acid value of 39 mg KOH / g, a weight-average molecular weight (Mw) of 15,000 measured by GPC (standard substance: polystyrene), and a double bond equivalent of 573.

[0104] Production Example 10 [Synthesis of alkali-soluble resin (A-10)] A glass flask equipped with a heating / cooling stirrer, a reflux condenser, and a nitrogen inlet tube was charged with 100.0 g of dicyclopentanyl methacrylate, 46.9 g of methacrylic acid, 127.3 g of methyl methacrylate, 148.5 g of (3,4-epoxycyclohexyl)methyl methacrylate, and 1,055.1 g of cyclopentanone. After the gas phase in the system was replaced with nitrogen, 29.6 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was added, and the mixture was heated to 65°C and reacted at the same temperature for 8 hours to obtain a solution containing alkali-soluble resin (A-10). The synthesized alkali-soluble resin (A-10) contains 15 mol % of repeating structural units (a1-1) derived from dicyclopentanyl methacrylate, 18 mol % of repeating structural units (a2-1) derived from methacrylic acid, 25 mol % of repeating structural units (a4-2) derived from (3,4-epoxycyclohexyl)methyl methacrylate, and 42 mol % of repeating structural units (a5-2) derived from methyl methacrylate. The synthesized alkali-soluble resin (A-10) has an acid value of 72 mg KOH / g and a weight-average molecular weight (Mw) of 11,000 as measured by GPC (standard substance: polystyrene).

[0105] The proportions of the repeating structural units and structural characteristics of the alkali-soluble resins (A-1) to (A-10) are shown in Table 1.

[0106]

[0107] Example 1 [Preparation of Photosensitive Resin Composition] A photosensitive resin composition having a solids content of 50% by mass was prepared by mixing 62.1% by mass (solids content) of a solution containing an alkali-soluble resin (A-1), 37.3% by mass of a photopolymerizable monomer (B-1) represented by the following formula, 0.5% by mass of a photopolymerization initiator (C) under the trade name Irgacure OXE01 (manufactured by BASF Japan Ltd.), and 0.1% by mass of a silicone surfactant (BYK-Chemie, BYK-307). The photopolymerizable monomer (B-1) had a Log P of 4.54 and a double bond equivalent of 332.

[0108] Examples 2 to 6 and Comparative Examples 1 to 7 [Preparation of Photosensitive Resin Compositions] Photosensitive resin compositions were prepared in the same manner as in Example 1, except for the formulation changes shown in Table 2. The photopolymerizable monomer (B-2) in Table 2 is represented by the following formula. The photopolymerizable monomer (B-2) has a Log P of 3.05 and a double bond equivalent of 152. Furthermore, "L-7001" in Table 2 is a polyether-modified silicone oil manufactured by Dow Toray Industries, Inc., and "FM-0721" in Table 2 is a reactive silicone manufactured by JNC Corporation.

[0109]

[0110] Next, the contact angle, water repellency, and pattern formability were measured or evaluated by the following methods using each of the photosensitive resin compositions prepared in Examples 1 to 6 and Comparative Examples 1 to 7. The results are shown in Table 2.

[0111] [Contact angle] Each of the curable resin compositions prepared in Examples 1 to 6 and Comparative Examples 1 to 7 was applied to a glass substrate by spin coating, and heated on a hot plate at 100°C for 120 seconds to form a coating film. Thereafter, the coating film was irradiated with light from an ultra-high pressure mercury lamp at 100 mJ / cm. 2 Irradiation (illuminance at 365 nm: 20 mW / cm 2 ), which was developed for 110 seconds using a 0.4% aqueous NaOH solution, and heated at 230°C for 30 minutes to form a cured film. Next, using a contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd., product number: DM-501), one drop of 1 μL of water was dropped onto the cured film, and the contact angle was measured.

[0112] [Water repellency] The water repellency was evaluated based on the contact angle measured according to the following criteria. The higher the contact angle, the better the water repellency. A: Contact angle of 90° or more B: Contact angle of 85° or more and less than 90° C: Contact angle of 80° or more and less than 85° D: Contact angle less than 80°

[0113] [Pattern Formability] Each of the curable resin compositions prepared in Examples 1 to 6 and Comparative Examples 1 to 7 was applied to a glass substrate by spin coating, and prebaked on a hot plate at 100°C for 120 seconds to form a coating film. Thereafter, the coating film was irradiated with light from an ultra-high pressure mercury lamp at an exposure gap of 150 μm and an intensity of 100 mJ / cm. 2Irradiated (illuminance at 365 nm: 20 mW / cm 2 ). The substrate was then developed using a 0.4% NaOH aqueous solution for 110 seconds and heated at 230°C for 30 minutes to form a cured film with a thickness of 50 µm, thereby producing a substrate with a cured film. The pattern formability was evaluated according to the following criteria: A: When the spacing was 100 µm, a pattern with a line width of 20 µm could be formed. B: When the spacing was 100 µm, a pattern with a line width of 30 µm could be formed. C: When the spacing was 100 µm, a pattern could not be formed (residue was generated).

[0114] As shown in Table 2, each of the curable resin compositions of Examples 1 to 6 was capable of forming a cured film with a high contact angle and excellent water repellency, and also had good pattern formability. On the other hand, the cured films obtained from the curable resin compositions of Comparative Examples 1, 2, and 5 had a low contact angle and poor water repellency. The curable resin composition of Comparative Example 6 contained a reactive silicone, but the cured film obtained from this curable resin composition had a low contact angle and poor water repellency. The curable resin compositions of Comparative Examples 3, 4, and 7 were capable of forming a cured film with a high contact angle and excellent water repellency, but had poor pattern formability.

[0115] The curable resin composition of the present invention is suitably used as a material for forming a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an optical waveguide, or a planarizing film.

Claims

1. A photosensitive resin composition comprising: an alkali-soluble resin (A) which contains a repeating structural unit (a1) having a hydrophobic group, a repeating structural unit (a2) having an acid group, and a repeating structural unit (a3) ​​having an organopolysiloxane structure, and in which the content of the repeating structural unit (a1) is more than 10 mol % and less than 45 mol %; a photopolymerizable monomer (B) having a Log P of 2.5 to 6.5; and a photopolymerization initiator (C).

2. The photosensitive resin composition according to claim 1, wherein the hydrophobic group of the repeating structural unit (a1) is an aromatic hydrocarbon group, an alicyclic saturated hydrocarbon group, an alicyclic unsaturated hydrocarbon group, or a group in which two or more of these groups are bonded.

3. The photosensitive resin composition according to claim 1, wherein the alkali-soluble resin (A) has an acid value of 40 to 100 mgKOH / g.

4. The photosensitive resin composition according to claim 1, wherein the alkali-soluble resin (A) further contains a repeating structural unit (a4) having a crosslinkable functional group.

5. The photosensitive resin composition according to claim 1, wherein the photopolymerizable monomer (B) has a functional group containing one or more ethylenically unsaturated double bonds and a ring structure, and the functional group is bonded to the ring structure directly or via a linking group.

6. The photosensitive resin composition according to claim 1, wherein the photopolymerizable monomer (B) has a double bond equivalent of 90 to 400.

7. A cured product obtained from the photosensitive resin composition according to any one of claims 1 to 6.

8. The cured product according to claim 7, which is a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an optical waveguide, or a planarizing film.

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