WO2020095789A1

WO2020095789A1 - Copolymer, and resin composition containing said copolymer

Info

Publication number: WO2020095789A1
Application number: PCT/JP2019/042553
Authority: WO
Inventors: 優介青木; 恭章川口
Original assignee: 昭和電工株式会社
Priority date: 2018-11-08
Filing date: 2019-10-30
Publication date: 2020-05-14
Also published as: TW202031702A

Abstract

Provided is an acrylic resin having thermosetting properties and having a superior low-refractive index. This copolymer (A) is characterized by having an acid value of 20 KOHmg/g or more and including: at least one structural unit selected from the group consisting of structural units derived from polymerizable monomers (a-1A) having a bridged cyclic hydrocarbon group having 10-20 carbon atoms and structural units derived from polymerizable monomers (a-1B) represented by chemical formula (1); a structural unit derived from a fluorine-containing (meth)acrylate (a-2) represented by chemical formula (2); a structural unit derived from an epoxy group-containing (meth)acrylate (a-3); a structural unit derived from an unsaturated carboxylic acid (a-4); and a structural unit derived from a hydroxy group-containing (meth)acrylate (a-6).

Description

Copolymer and resin composition containing the copolymer

The present invention relates to a copolymer, a resin composition containing the copolymer, and a resist.
The present application claims priority based on Japanese Patent Application No. 2018-210790 filed in Japan on November 8, 2018, and the content thereof is incorporated herein.

In recent years, from the viewpoint of resource saving and energy saving, photosensitive resin compositions curable by active energy rays such as ultraviolet rays and electron rays have been widely used in the fields of various coatings, printing, paints, adhesives and the like. Also in the field of electronic materials such as printed wiring boards, photosensitive resin compositions curable by active energy rays can be used as solder resists, color filters, black matrices, black column spacers, photo spacers, protective film resists, etc. It is used. Furthermore, the required properties for curable photosensitive resin compositions are becoming more diverse and sophisticated. These required properties include, for example, short-time curability in consideration of productivity, low-temperature curability that suppresses thermal damage to applied members, and the like.

Also, as a resist containing a thermosetting resin having an epoxy group, a chemically amplified resist using a photoacid generator as a photosensitizer is well known. For example, in an example of using a resin composition containing a resin containing a structural unit having an epoxy group and a photoacid generator, a photoacid generator generates a protonic acid by exposure, and the generated acid cleaves the epoxy group. Causes a crosslinking reaction. As a result, the resin becomes insoluble in the developing solution and a pattern is formed. Furthermore, the heat treatment after the exposure causes the resin to move in the solid phase of the resist, and the acid causes the chemical change of the resist resin or the like to be catalytically amplified. ..

Above all, the low reflectivity of electronic material members is emphasized in order to enhance the functionality of various devices. Therefore, in recent years, the development of members with the theme of low reflectivity has been earnestly studied. For example, in microlenses used in digital cameras, smartphones, etc., there is an increasing demand for coating a low reflectance layer along the surface of the microlens. By coating the low-reflectance layer, the reflected light from the concave portions between the lenses can be significantly suppressed, the S / N ratio can be improved, and a high-quality image with little noise can be realized.
In addition, in an image display device such as a liquid crystal display or an organic EL display, when external light such as sunlight or a fluorescent lamp is reflected, the external light diffuses after reaching the inside of the substrate of the image display device and the visibility of the screen deteriorates. .. Therefore, for the purpose of improving visibility, there is an increasing demand for a low-reflection display in which various members constituting the image display device substrate are made to have a low reflectance to minimize the reflection of external light. Examples of these members include a transparent substrate, a color filter, a black matrix, a column spacer and a protective film.

In order to meet these demands, it is required to reduce the reflectance of a photosensitive resin composition used as a resist for coating the surface of a microlens, and to manufacture a member constituting an image display device substrate. There is a demand for lowering the reflectance of the photosensitive resin composition used as a resist. That is, it is required to reduce the reflectance of the resin itself that constitutes these photosensitive resin compositions.

As shown by the Fresnel equation, there is a positive correlation between the reflectance and the refractive index. Therefore, it is effective to introduce into the resin an atomic group exhibiting a low refractive index as a method for achieving a low reflectance of the resin constituting the photosensitive resin composition. One of the most effective methods is to introduce a fluorine atom. Above all, an acrylic resin obtained by polymerizing a fluorine-containing (meth) acrylate is particularly noted as a fluorine atom-introduced resin that can be provided simply and efficiently. However, the fluorine atom-introduced resin has poor solubility and poor affinity with other photosensitive resin compositions. Therefore, when a composition containing the resin is applied to a substrate, it becomes a ball on the substrate. As a result, there often occurs a problem that the cured film cannot be formed smoothly.

Therefore, as shown in Patent Documents 1 and 2, by introducing a fluorine atom introducing another monomer group and a fluorine-containing (meth) acrylate, the solubility is improved and smooth coatability of the cured film is realized. A resin can be provided.

On the other hand, strict dimensional accuracy is required to manufacture a coating on the surface of a microlens or a member constituting an image display device substrate. When forming these members, a photolithography method is widely used in which the photosensitive resin composition is applied, exposed, developed, and baked, and the members are pinpointed without any defects such as pinholes at required portions. It is used.
Generally, the photolithography method includes exposure with active energy rays such as ultraviolet rays and electron beams, and a developing step with an alkali developing solution. The photosensitive resin composition used in this method is required to have sensitivity to active energy rays and alkali developability. Therefore, in the photosensitive resin composition used in this method, an alkali-soluble resin is used as the binder of the coating film forming the member. In addition, a reactive diluent, a photopolymerization initiator, and if necessary, an additive such as a colorant are included.

To improve the sensitivity of the alkali-soluble resin, it is necessary to introduce a functional group that causes a reaction during exposure to active energy rays. As such a functional group, an ethylenically unsaturated group is generally mentioned. On the other hand, in order to improve the alkali developability, the method of introducing an acid group is the most general. Examples of the acid group include a carboxy group, a phosphoric acid group and a sulfonic acid group. When a black matrix, a color filter (a colored pattern of each pixel of R / G / B), a protective film, and the like are repeatedly formed like an image display device substrate, an alkali-soluble resin as a binder of a coating film is used. , High degradability, high heat yellowing, high solvent resistance, etc. are required.

JP, 2007-119572, A JP, 2013-6928, A

However, the conventional resin has a low degree of fluorine substitution in the fluorine-containing (meth) acrylate and a low composition ratio of the fluorine-containing (meth) acrylate in all the monomers, so that it is possible to provide a satisfactory low refractive index acrylic resin. Is insufficient. Furthermore, conventional resins are not curable resins that can be cured by active energy rays such as ultraviolet rays and electron beams, but exhibit photocurability by blending with other photosensitive resins, additives, and the like. For the purpose of improving productivity, a photosensitive resin composition that exhibits photocurability with a single liquid is in high demand, but a photosensitive acrylic resin having a satisfactory low refractive index has not been provided yet. Furthermore, fluorine-containing acrylic resins, including conventional resins, generally have poor affinity with alkali developers, and further improvement in alkali developability is necessary to satisfy the strict dimensional accuracy of the members. is there.
The present invention has been made in order to solve the above problems, while providing both curability and alkali developability, provide an acrylic resin having an excellent low refractive index in one liquid, by the resin An object of the present invention is to provide a photosensitive resin composition used for a resist that contributes to low reflection and high definition of all electronic material members such as microlenses and image display devices.

That is, the present invention is shown in the following [1] to [11].

[1] A structural unit derived from a polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms and a structural unit derived from a polymerizable monomer (a-1B) represented by the following chemical formula (1). At least one selected from the group consisting of units,
A structural unit derived from a fluorine-containing (meth) acrylate (a-2) represented by the following chemical formula (2),
A structural unit derived from an epoxy group-containing (meth) acrylate (a-3) and a structural unit derived from an unsaturated carboxylic acid (a-4),
A copolymer (A) containing a structural unit derived from a hydroxy group-containing (meth) acrylate (a-6) and having an acid value of 20 KOHmg / g or more.

(X and X ′ in the formula (1) each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 4 carbon atoms, and R 1 and R 2 each independently. A hydrogen atom, a carboxy group, or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may have a cyclic structure connecting R1 and R2.)

(In the formula (2), R3 represents a hydrogen atom or a methyl group, L represents —O—, —O—CH ₂ —CH (OH) —CH ₂ —, —O—NH—C (═O) —CH. ₂ --CH _2-, each Z independently represents a hydrogen atom, a fluorine atom, a CF ₃ group, a C ₂ F ₅ group, a C ₃ F ₇ group or a hydroxy group, and n is 0 to It is an integer of 12. However, at least three fluorine atoms are included in the formula (2).
[2] The copolymer (A) according to [1], which has a refractive index of less than 1.50.
[3] The copolymer (A) according to [1] or [2], wherein the copolymer (A) has a fluorine equivalent of 250 g / mol or less.
[4] The polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms is dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate. And the copolymer (A) according to any one of [1] to [3], containing at least one selected from the group consisting of :, and adamantyl (meth) acrylate.
[5] The structural unit derived from the polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms and the polymerizable monomer (a-1B) represented by the following chemical formula (1). The total proportion of the constituent units derived from the compound is 1 to 40 mol%, the proportion of the constituent units derived from the fluorine-containing (meth) acrylate (a-2) represented by the chemical formula (2) is 9 to 80 mol%, and the epoxy group is Containing 5 to 30 mol% of constituent units derived from (meth) acrylate (a-3), 5 to 30 mol% of constituent units derived from unsaturated carboxylic acid (a-4), containing hydroxy group The copolymer (A) according to any one of [1] to [4], wherein the ratio of the structural unit derived from the (meth) acrylate (a-6) is 5 to 30 mol%.
[6] A resin composition containing the copolymer (A) according to any one of [1] to [5] and a solvent (B).
[7] The resin composition according to [6], which further contains a reactive diluent (C).
[8] The resin composition according to [7], further containing a photopolymerization initiator (D), and the reactive diluent (C) containing an ethylenically unsaturated double bond.
[9] The resin composition according to any one of [6] to [8], which further contains a compound (G) that generates an acid when irradiated with heat and / or ultraviolet rays.
[10] contains a colorant (E),
The resin composition according to any one of [6] to [9], wherein the colorant (E) is at least one selected from the group consisting of dyes and pigments.
[11] A resist comprising a cured product of the resin composition according to any one of [6] to [10].

According to the present invention, an acrylate-based copolymer having an excellent low refractive index while exhibiting thermosetting properties can be provided. Further, the photosensitive resin composition of the present invention can be suitably used for a resist that contributes to low reflection and high definition of all electronic material members such as microlenses and image display devices.

The present invention will be described in detail below.

[Copolymer (A)]
The copolymer (A) of the present invention comprises a structural unit derived from a polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms and a polymerizable monomer represented by the above chemical formula (1). At least one selected from the group consisting of structural units derived from (a-1B), a structural unit derived from the fluorine-containing (meth) acrylate (a-2) represented by the chemical formula (2), and an epoxy group-containing Containing a structural unit derived from (meth) acrylate (a-3), a structural unit derived from unsaturated carboxylic acid (a-4), and a structural unit derived from hydroxy group-containing (meth) acrylate (a-6). The acid value is 20 KOHmg / g or more. Here, the (meth) acrylate means one or more selected from methacrylate and acrylate.

The copolymer (A) of the present invention comprises a polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms and a polymerizable monomer (a-1B) represented by the following chemical formula (1). ), A fluorine-containing (meth) acrylate (a-2) represented by the following chemical formula (2), an epoxy group-containing (meth) acrylate (a-3), and an unsaturated group. It is a copolymer of a monomer (M) containing a carboxylic acid (a-4) and a hydroxy group-containing (meth) acrylate (a-6).
The monomer (M) of this embodiment is other than the above-mentioned monomers (a-1A), (a-1B), (a-2), (a-3), (a-4) and (a-6). The polymerizable monomer (a-7) may be included.

The copolymer (A) of the present invention is derived from an epoxy group-containing (meth) acrylate (a-3), an unsaturated carboxylic acid (a-4) and a hydroxy group-containing (meth) acrylate (a-6). By including the structural unit, it is possible to develop curability by heat and alkali developability. With this structural unit, sufficient hardness of the cured product is exhibited, and high solvent resistance is exhibited. Furthermore, by introducing a carboxy group or a hydroxy group as the alkali developing group, the affinity of the copolymer with the alkali developing solution is increased. By using such a copolymer, a highly precise cured pattern can be formed and strict dimensional accuracy is realized. Specifically, the development of curability is achieved by the thermal crosslinking reaction between the carboxy group and the epoxy group, and at the same time, the alkali developability can be effectively enhanced by introducing the carboxy group and the hydroxy group.

[Polymerizable Monomer (a-1A)]
The polymerizable monomer (a-1A) (hereinafter sometimes simply referred to as “monomer (a-1A)”) has a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms. Here, the bridged cyclic hydrocarbon means one having a structure represented by the following formula (3) or (4) represented by adamantane and norbornane, and the bridged cyclic hydrocarbon group is , Refers to a group corresponding to the rest of the structure except for some hydrogen. Further, the polymerizable monomer (a-1A) does not include the later-described polymerizable monomer (a-1B).

(In the formula (3), A and B each represent a linear or branched alkylene group (including a cyclic group), and R4 represents a hydrogen atom or a methyl group. Even if A and B are the same, They may be different, or the branches of A and B may be connected to form a ring.)

(In the formula (4), A ′, B ′, and D each represent a linear or branched alkylene group (including cyclic group), and R 5 represents a hydrogen atom or a methyl group. A ′, B ′, D may be the same or different, and the branches of A ', B', and D may be connected to each other to form a ring.)

The monomer (a-1A) is preferably a (meth) acrylate having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms, and has an adamantyl (meth) acrylate or a structure represented by the following formula (5) ( More preferred is (meth) acrylate. ‥

(In formula (5), R6 to R8 each represent a hydrogen atom or a methyl group. R9 and R10 may be a hydrogen atom or a methyl group, or may be bonded to each other to form a saturated or unsaturated ring. The ring is preferably a 5-membered ring or a 6-membered ring. * Represents a bond linked to the (meth) acryloyloxy group.)

Examples of the monomer (a-1A) include dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate and adamantyl (meth) acrylate. These may be used alone or in combination of two or more.

[Polymerizable Monomer (a-1B)]
The polymerizable monomer (a-1B) (hereinafter sometimes simply referred to as “monomer (a-1B)”) is a monomer represented by the following general formula (1).

The monomer (a-1B) is not particularly limited as long as it has the chemical structure represented by the general formula (1). In the general formula (1), examples of X and X'representing a linear or branched hydrocarbon group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group. Group, isobutyl group, t-butyl group and the like. In addition, examples of the substituent of the hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, which is represented by R1 and R2, include an alkoxy group and an aryl group. Examples of R1 and R2 are methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, t-amyl group, stearyl group, lauryl group, 2-ethylhexyl group. A linear or branched alkyl group such as; cyclohexyl group, t-butylcyclohexyl group, dicyclopentadienyl group, tricyclodecanyl group, isobornyl group, adamantyl group, 2-methyl-2-adamantyl group, etc. Examples thereof include a cyclic group; an alkyl group substituted with an alkoxy group such as a 1-methoxyethyl group and a 1-ethoxyethyl group; an alkyl group substituted with an aryl group such as a phenylaralkyl group.

Examples of the monomer (a-1B) having the chemical structure represented by the general formula (1) include norbornene, norbornene (bicyclo [2.2.1] hept-2-ene), and 5-methylbicyclo [2.2]. .1] hept-2-ene, 5-ethylbicyclo [2.2.1] hept-2-ene, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-ethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-ene, dicyclopentadiene, tricyclo [5.2.1.0 ^2,6 ] deca-8-ene, tricyclo [5.2.1.0 ^2,6 ] deca-3 -Ene, tricyclo [4.4.0.1 ^2,5 ] undec-3-ene, tricyclo [6.2.1.0 ^1,8 ] undec-9-ene, tricyclo [6.2.1.0] ^1,8 ] undec-4-ene, tetracyclo [4.4.0.1 ^2,5 . 1 ^{7, 10} . 0 ^1,6 ] dodec-3-ene, 8-methyltetracyclo [4.4.0.1 ^2,5 . 1 ^{7, 10} . 0 ^1,6 ] dodec-3-ene, 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,12 ] Dodeca-3-ene, 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^{7, 10} . 0 ^1,6 ] dodec-3-ene, pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13] pentadeca-4-ene, pentacyclo [7.4.0.1 ^2,5. 1 ^{9 and 12} . 0 ^8,13] pentadeca-3-ene, and the like. These may be used alone or in combination of two or more.
Among them, it is preferable to use one or more selected from adamantyl (meth) acrylate, a (meth) acrylate having a structure represented by the above formula (5), and norbornene. Dicyclopentenyl (meth) acrylate, dicyclopenta It is more preferable to use one or more selected from nyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate and norbornene.

Use of the above-mentioned monomer (a-1A) and / or the above-mentioned monomer (a-1B) contributes to smooth coatability of a cured film, high thermal decomposition resistance, and high heat yellowing. Further, it is possible to suppress the decrease in the solubility of the copolymer in the solvent due to the presence of fluorine. One of the monomer (a-1A) and the monomer (a-1B) may be used, or both of them may be used.

[Fluorine-containing (meth) acrylate (a-2)]
The fluorine-containing (meth) acrylate (a-2) (hereinafter sometimes simply referred to as “monomer (a-2)”) is a fluorine-containing (meth) acrylate represented by the following chemical formula (2).

(In the formula (2), R3 represents a hydrogen atom or a methyl group, L represents —O—, —O—CH ₂ —CH (OH) —CH ₂ —, —O—NH—C (═O) —CH. ₂ --CH _2-, each Z independently represents a hydrogen atom, a fluorine atom, a CF ₃ group, a C ₂ F ₅ group, a C ₃ F ₇ group or a hydroxy group, and n is 0 to It is an integer of 12. However, at least three fluorine atoms are included in the formula (2).

The fluorine-containing (meth) acrylate (a-2) is not particularly limited as long as it is represented by the above formula (2). The use of the fluorine-containing (meth) acrylate (a-2) makes it possible to lower the refractive index of the resin, but the effect becomes remarkable when the monomer contains three or more fluorine atoms. When n ≧ 13, further lowering of the refractive index can be expected, but there is a risk that the hardness of the cured film may not be sufficiently exhibited, so that n is in the range of 0 to 12.

As the fluorine-containing (meth) acrylate (a-2), a commercially available product may be used, or a reactive (meth) acrylic acid such as (meth) acrylic acid, glycidyl (meth) acrylate, or 2-isocyanatoethyl (meth) acrylate may be used. ) Acrylic acid derivative and fluoroalcohol may be self-condensed and prepared. Specific examples include 2,2,2-trifluoroethyl (meth) acrylate, 3,3,3-trifluoropropyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate and 3 , 3,4,4-Tetrafluorobutyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, 3,3,4,4,4-pentafluorobutyl (meth) acrylate 1H, 1H-perfluoro-n-butyl (meth) acrylate, 1H, 1H-perfluoro-n-pentyl (meth) acrylate, 1H, 1H-perfluoro-n-hexyl (meth) acrylate, 1H, 1H-perfluoro-n -Octyl (meth) acrylate, 1H, 1H-perfluoro-n-decyl (meth) acrylate, 1H 1H-perfluoro-n-dodecyl (meth) acrylate, 1H, 1H-perfluoroisobutyl (meth) acrylate, 1H, 1H-perfluoroisooctyl (meth) acrylate, 1H, 1H-perfluoroisododecyl (meth) acrylate, 1H, 1H , 5H-octafluoropentyl (meth) acrylate, 1H, 1H, 5H-perfluoropentyl (meth) acrylate, 1H, 1H, 6H-perfluorohexyl (meth) acrylate, 1H, 1H, 7H-perfluoroheptyl (meth) acrylate, 1H, 1H, 8H-perfluorooctyl (meth) acrylate, 1H, 1H, 9H-perfluorononyl (meth) acrylate, 1H, 1H, 10H-perfluorodecyl (meth) acrylate, 1H, 1H, 11H Perfluoroundecyl (meth) acrylate, 1H, 1H, 12H-perfluorododecyl (meth) acrylate, 2- (perfluoro-n-propyl) ethyl (meth) acrylate, 2- (perfluoro-n-butyl) ethyl (meth) acrylate , 2- (perfluoro-n-hexyl) ethyl (meth) acrylate, 2- (perfluoro-n-octyl) ethyl (meth) acrylate, 2- (perfluoro-n-decyl) ethyl (meth) acrylate, 2- (perfluoro Isobutyl) ethyl (meth) acrylate, 2- (perfluoroisooctyl) ethyl (meth) acrylate, 1H, 1H, 2H, 2H-nonafluorohexyl (meth) acrylate, 1H, 1H, 2H, 2H-tridecafluorooctyl ( (Meth) acrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl (meth) acrylate and the like can be mentioned. These may be used alone or in combination of two or more.
Of these, fluoroalkyl (meth) acrylates (a-2) having 3 to 20 fluorine atoms are preferable from the viewpoint of easy production of the copolymer (P1).

[Epoxy group-containing (meth) acrylate (a-3)]
The epoxy group-containing (meth) acrylate (a-3) (hereinafter sometimes simply referred to as “monomer (a-3)”) is not particularly limited as long as it is a monomer having an epoxy group and an ethylenically unsaturated group. Not done. Specific examples include glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and 3,4-epoxycyclohexylmethyl (meth) acrylate. In particular, glycidyl (meth) acrylate is preferable from the viewpoint of easy availability and good reactivity.
The (meth) acrylate having a hydroxy group, a carboxy group, and an epoxy group is a monomer (a-3).

[Unsaturated carboxylic acid (a-4)]
The unsaturated carboxylic acid (a-4) (hereinafter sometimes simply referred to as “monomer (a-4)”) includes, among acid groups, a carboxy group which has a high reactivity with an epoxy group and an ethylenic unsaturated group. There is no particular limitation as long as it is a monomer having a group. Specific examples of the monomer include (meth) acrylic acid, itaconic acid, crotonic acid, cinnamic acid, 2- (meth) acryloyloxyethylsuccinic acid, 2- (meth) acryloyloxyethylphthalic acid, 2- (meth) acryloyl Examples thereof include oxyethylhexahydrophthalic acid. In particular, (meth) acrylic acid is preferable from the viewpoints of easy availability and good reactivity.
The (meth) acrylate having a carboxy group and an epoxy group is a monomer (a-3) and is not included in the monomer (a-4).

[Hydroxy group-containing (meth) acrylate (a-6)]
The hydroxy group-containing (meth) acrylate (a-6) is not particularly limited as long as it is a (meth) acrylate containing one or more hydroxy groups. Specific examples include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-hydroxypentyl (meth) acrylate, 4-hydroxypentyl (meth) acrylate, 5-hydroxypentyl (meth) acrylate, 4-hydroxyhexyl (meth) acrylate, 5-hydroxyhexyl (meth) acrylate, 6-hydroxyhexyl ( (Meth) acrylate, 5-hydroxy-3-methyl-pentyl (meth) acrylate, cyclohexane-1,4-dimethanol-mono (meth) acrylate, 2- (2-hydroxyethyloxy) ethyl (meth) a Relate, 2,3-dihydroxy (meth) acrylate, butane triol mono (meth) acrylate, pentane triol mono (meth) acrylate.
The monomer (a-3) and the monomer contained in the monomer (a-4) are not included in the monomer (a-6).

[Other polymerizable monomers (a-7)]
The copolymer (A) of the present invention may further contain a constituent unit derived from another polymerizable monomer (a-7). That is, the monomer (M) of the copolymer (A) of the present invention further contains another polymerizable monomer (a-7) (hereinafter sometimes simply referred to as “monomer (a-7)”). May be included. The other polymerizable monomer (a-7) is the same as the above-mentioned monomers (a-1A), (a-1B), (a-2), (a-3), (a-4) and (a-6). Copolymerizable monomers other than those shown. This monomer (a-7) is generally a radically polymerizable compound having an ethylenically unsaturated group, and specific examples thereof include dienes such as butadiene; methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl. (Meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) ) Acrylate, neopentyl (meth) acrylate, benzyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, cyclopentyl (Meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) acrylate, rosin (meth) acrylate, allyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, triphenylmethyl (meth) (Meth) acrylic acid esters such as acrylate, cumyl (meth) acrylate, 3- (N, N-dimethylamino) propyl (meth) acrylate, naphthalene (meth) acrylate, anthracene (meth) acrylate; (meth) acrylic acid Amide, (meth) acrylic acid N, N-dimethylamide, (meth) acrylic acid N, N-diethylamide, (meth) acrylic acid N, N-dipropylamide, (meth) acrylic acid N, N-di-iso -Propyl Amide, (meth) acrylic acid amide such as (meth) acrylic acid anthracenylamide; (meth) acrylic acid anilide, (meth) acryloylnitrile, acrolein, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N -Vinyl compounds such as vinylpyrrolidone, vinylpyridine, vinyl acetate and vinyltoluene; styrene, α-alkyl, o-alkyl, m-alkyl, p-alkyl, nitro, cyano, amide derivatives of styrene; N-phenylmaleimide, N -Maleimides such as -cyclohexylmaleimide, N-laurylmaleimide and N- (4-hydroxyphenyl) maleimide; unsaturated dicarboxylic acid diesters such as diethyl citraconic acid, diethyl maleate, diethyl fumarate, diethyl itaconic acid and the like. These may be used alone or in combination of two or more, if necessary.

[Ratio of Structures Derived from Each Monomer of Copolymer (A)]
In the copolymer (A) of the present invention, the ratio of each monomer-derived structure is the value of the molar ratio of each polymerizable monomer added for the copolymerization reaction. The mixing ratio (molar ratio) of each monomer is not particularly limited, but when the total of all monomers is 100 mol%, the total mixing ratio of the monomer (a-1A) and the monomer (a-1B) is preferably It is 1 to 40 mol%, more preferably 2 to 20 mol%. When the mixing ratio of the monomer (a-1A) and the monomer (a-1B) is 1 mol% or more, desired thermal decomposition resistance, thermal yellowing resistance, and good solubility in a solvent can be obtained. On the other hand, when the mixing ratio is 40 mol% or less, the mixing ratios of the monomer (a-2), the monomer (a-3), the monomer (a-4), and the monomer (a-6) are sufficiently high, A copolymer (A) having a desired refractive index, curability, and alkali developability can be obtained. The mixing ratio of the monomer (a-2) is preferably 9 to 80 mol%, more preferably 20 to 70 mol%. When the blending ratio of the monomer (a-2) is 9 mol% or more, the copolymer (A) having a sufficiently low refractive index can be obtained. When the blending ratio of the monomer (a-2) is 80 mol% or less, the monomer (a-1A) and / or the monomer (a-1B), the monomer (a-3), the monomer (a-4), and the monomer The blending ratio of (a-6) is sufficiently high, and a copolymer (A) having desired thermal decomposition resistance, curability, alkali developability, and good solubility in a solvent can be obtained. The mixing ratio of the monomer (a-3) is preferably 5 to 30 mol%, more preferably 9 to 25 mol%. When the compounding ratio of the monomer (a-3) is 5 mol% or more, sufficient curability can be exhibited, and compared with a resin composition obtained by mixing a non-curable fluororesin with another curable component. A curable resin composition having good affinity can be provided. When the mixing ratio of the monomer (a-3) is 25 mol% or less, the monomer (a-1A) and / or the monomer (a-1B) and the monomer (a-2), the monomer (a-4), and the monomer The blending ratio of (a-6) is sufficiently high, and the copolymer (A) having desired thermal decomposition resistance, refractive index, and alkali developability can be obtained.

The mixing ratio of the unsaturated carboxylic acid (a-4) is preferably 5 to 30 mol%, more preferably 9 to 25 mol%. When the blending ratio of the monomer (a-4) is 5 mol% or more, a desired alkali developability can be exhibited, and a sufficient curability can be exhibited by reacting with the epoxy group derived from the monomer (a-3). .. When the blending ratio of the monomer (a-4) is 30 mol% or less, the monomer (a-1A) and / or the monomer (a-1B) and the monomer (a-2), the monomer (a-3), and the monomer The blending ratio of (a-6) becomes sufficiently large, and the copolymer (A) having desired thermal decomposition resistance, refractive index, and curability can be obtained.
The mixing ratio of the hydroxy group-containing (meth) acrylate (a-6) is preferably 5 to 30 mol%, more preferably 10 to 26 mol%. When the blending ratio of the monomer (a-6) is 5 mol% or more, desired alkali developability is exhibited and a high-definition cured pattern can be formed. When the blending ratio of the monomer (a-6) is 30 mol% or less, the monomer (a-1A) and / or the monomer (a-1B) and the monomer (a-2), the monomer (a-3), and the monomer The blending ratio of (a-4) is sufficiently high, and the copolymer (A) having desired thermal decomposition resistance, refractive index, and curability can be obtained.

[Ratio of Structures Derived from Each Monomer of Copolymer (A)]
The unsaturated group-containing copolymer (A) preferably has a structure represented by the following formula (6).

(In the formula (6), X and X ′ each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 4 carbon atoms, and R 1 and R 2 are each independently It is a hydrocarbon group having 1 to 20 carbon atoms which may have a hydrogen atom, a carboxy group or a substituent, and may have a cyclic structure connecting R1 and R2.
R11 is a substituent having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms. L is a chain of any one of —O—, —O—CH ₂ —CH (OH) —CH ₂ —, and —O—NH—C (═O) —CH ₂ —CH ₂ —. Each Z independently represents a hydrogen atom, a fluorine atom, a CF ₃ group, a C ₂ F ₅ group, a C ₃ F ₇ group or a hydroxy group, and n is an integer of 0 to 12. However, in the formula (6), at least three fluorine atoms are included.
R12 to 16 each independently represent a hydrogen atom or a methyl group, L'is a divalent hydrocarbon group having 1 to 6 carbon atoms which may have a substituent, and L "is a hydrogen atom or A hydrocarbon group having 1 to 6 carbon atoms, Q independently represents a hydrogen atom, a hydroxy group, a methyl group, an ethyl group, a propyl group or a butyl group, m is an integer of 0 to 10, and Qs are May be connected to form a cyclic structure, provided that at least one hydroxy group in Q is included.
x1, x2, y, g, h, and i are molar ratios of the respective constituent units, y, g, h, and i are larger than 0, and x1 and x2 may be 0. However, x1 and x2 are never 0 at the same time. The bonding order of each structural unit is not limited to that shown in the formula, and a block polymer or a random polymer may be formed. )

R11 is preferably a substituent having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms, more preferably adamantyl (meth) acrylate or a group having a structure represented by the following formula (5). preferable. ‥

Examples of the linear or branched hydrocarbon group having 1 to 4 carbon atoms represented by X and X ′ in the formula (6) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group. Group, isobutyl group, t-butyl group and the like. Examples of the substituent of the hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, which is represented by R1 and R2, include an alkoxy group and an aryl group. Examples of R1 and R2 are methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, t-amyl group, stearyl group, lauryl group, 2-ethylhexyl group. A linear or branched alkyl group such as; cyclohexyl group, t-butylcyclohexyl group, dicyclopentadienyl group, tricyclodecanyl group, isobornyl group, adamantyl group, 2-methyl-2-adamantyl group, etc. Examples thereof include a cyclic group; an alkyl group substituted with an alkoxy group such as a 1-methoxyethyl group and a 1-ethoxyethyl group; an alkyl group substituted with an aryl group such as a phenylaralkyl group.
L and Z in the formula (6) are the same as those described in the formula (2). Examples of the divalent hydrocarbon group having 1 to 6 carbon atoms represented by L ′ in the formula (6) include methylene group, ethylene group, propylene group, cyclohexylene group and the like. Examples of the hydrocarbon group having 1 to 6 carbon atoms represented by L ″ include a methyl group, an ethyl group, a methylene group, an ethylene group, a propylene group, etc. Q is preferably a hydrogen atom or a hydroxy group. Is preferably 1 to 6, and more preferably 1 to 3.

[Copolymerization reaction (method for producing copolymer (A)]]
The copolymer (A) of the present invention can be produced by using a copolymerization reaction. The copolymerization reaction carried out in the present invention can be carried out according to a radical polymerization method known in the art. For example, a monomer used for copolymerization may be dissolved in a solvent, a polymerization initiator may be added to the solution, and the reaction may be performed at 50 to 130 ° C. for 1 to 20 hours. Alternatively, the monomer used for the copolymerization and the polymerization initiator may be added dropwise to the solvent adjusted to 50 to 130 ° C. for the reaction.

The solvent that can be used in this copolymerization reaction is not particularly limited as long as it is inert to radical polymerization, and a commonly used organic solvent can be used. Specific examples include glycol ether solvents such as propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate; aromatic solvents such as toluene and xylene; ester solvents such as ethyl acetate, isopropyl acetate and ethyl lactate. These may be used alone or in combination of two or more. Of these, glycol ether solvents are preferred.

The amount of the solvent used in the copolymerization reaction is not particularly limited, but is generally 30 to 1000 parts by mass, preferably 50 to 800 parts by mass, when the total amount of the monomers used in the copolymerization is 100 parts by mass. In particular, when the amount of the solvent used is 1000 parts by mass or less, the decrease in the molecular weight of the copolymer (P) is suppressed by the chain transfer action, and the viscosity of the copolymer (P) is controlled within an appropriate range. be able to. Further, by using the solvent in an amount of 30 parts by mass or more, an abnormal polymerization reaction can be prevented, the polymerization reaction can be stably performed, and coloring and gelation of the copolymer (P) can be prevented. You can also

The polymerization initiator that can be used in this copolymerization reaction is not particularly limited as long as it can initiate radical polymerization, and a commonly used organic peroxide catalyst or azo compound can be used. You can Specifically, azobisisobutyronitrile, azobisisovaleronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), azobis (2-methylpropionic acid) dimethyl, benzoyl peroxide, dicumyl Peroxide, diisopropyl peroxide, di-t-butyl peroxide, t-butyl peroxybenzoate, t-hexyl peroxybenzoate, t-butyl peroxy-2-ethylhexanoate, t-hexyl peroxy-2- Examples thereof include ethylhexanoate and 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate.
These may be used alone or in combination of two or more, and it is desirable to select a radical polymerization initiator having an appropriate half-life according to the polymerization temperature.

The amount of the polymerization initiator used in this copolymerization reaction is not particularly limited, but is generally 0.5 to 20 parts by mass, preferably 1.0 to 10 parts by mass when the total amount of the monomers used in the copolymerization is 100 parts by mass. 10 parts by mass.

The fluorine equivalent of the copolymer (A) is the mass of the polymer per the number of moles of the fluorine atom, and is a calculated value calculated based on the amount of the monomer used. If this value is 250 g / mol or less, the refractive index of the acrylic resin as an acrylic resin that exhibits photocurability by adding an unsaturated carboxylic acid (a-4) or an ethylenically unsaturated group-containing reactive monomer (b-2) It is possible to obtain the copolymer (A) of the present invention having a sufficiently low value. The lower this value is, the lower the refractive index of the copolymer (A) can be, but the solubility of the copolymer in a solvent is lowered, and the affinity with other photosensitive resin compositions is deteriorated. There is a fear. Therefore, the fluorine equivalent is preferably 30 to 250 g / mol, more preferably 50 to 250 g / mol.

[Characteristics of copolymer]
The molecular weight (polystyrene-equivalent weight average molecular weight) of the copolymer (A) of the present invention is preferably 1,000 to 50,000, and more preferably 3,000 to 40,000. When this molecular weight is 1,000 or more, the solvent resistance and thermal decomposition resistance of the cured film can be sufficiently secured. On the other hand, when the molecular weight is 50,000 or less, the molecular weight and the viscosity can be controlled in an appropriate range, which is practical.

The acid value (JIS K6901 5.3) of the copolymer (A) of the present invention is usually 20 KOHmg / g or more, preferably 20 to 300 KOHmg / g, and more preferably 30 to 200 KOHmg / g. If the acid value is less than 20 KOHmg / g, developability may be deteriorated and unexposed portions (non-cured portions) may be generated as residues. On the other hand, when the acid value is 300 KOHmg / g or less, the exposed portion (cured portion) is not easily dissolved in the alkali developing solution.

The hydroxyl equivalent of the copolymer (A) of the present invention is preferably 200 to 4000 g / mol, more preferably 200 to 2500 g / mol. By introducing fluorine, the water repellency of the alkali developer is increased, but by controlling the hydroxyl group equivalent to 4000 g / mol or less, more preferably 2500 g / mol or less, the water repellency of the alkali developer is suppressed and good developing property is obtained. Can be realized. On the other hand, when the hydroxyl group equivalent is 200 g / mol or more, the introduction amount of other substituents necessary for the present invention can be sufficiently secured, and desired curability, heat decomposition resistance, heat yellowing and refractive index can be obtained.

The epoxy equivalent of the copolymer (A) of the present invention is preferably 300 to 3000 g / mol, more preferably 500 to 2000 g / mol. An unsaturated group equivalent of 3000 g / mol or less, more preferably 2000 g / mol or less, is required to provide high sensitivity and desired thermosetting property. On the other hand, when the epoxy equivalent is low, the storage stability of the copolymer (A) may be easily deteriorated. Therefore, the epoxy equivalent is preferably 300 g / mol or more, more preferably 500 g / mol or more.

Also, the refractive index of the copolymer (A) is preferably less than 1.50 under the conditions of 589 nm and 20 ° C. When it is less than 1.50, the refractive index is sufficiently lower than the refractive index of the fluorine-free photocurable acrylic resin, and good low reflectance of the cured film can be obtained.

[Resin composition]
The resin composition of the present invention contains at least the copolymer (A) and the solvent (B). The resin composition of the present invention may further contain a reactive diluent (C), a photopolymerization initiator (D), a colorant (E), a compound (G) which generates an acid upon irradiation with heat and / or ultraviolet rays, and the like. Good. For example, one embodiment of the resin composition of the present invention includes a copolymer (A), a solvent (B), a reactive diluent (C), and a photopolymerization initiator (D), thereby forming a photosensitive resin. It can be a composition. The reactive diluent (C) preferably contains a vinyl group or an ethylenically unsaturated double bond such as a (meth) acryloyloxy group. In addition, another embodiment of the resin composition includes a copolymer (A), a solvent (B), and a compound (G) that generates an acid upon irradiation with ultraviolet rays, thereby providing a thermosetting resin composition or a photosensitive resin composition. It can be a resin composition. In that case, a reactive diluent (C), a photopolymerization initiator (D), a colorant (E) and the like may be further contained.

[Solvent (B)]
The solvent (B) is not particularly limited as long as it is a solvent that does not react with the copolymer (A). As the solvent (B), the same solvent as used in the production of the copolymer (A) can be used. Further, the solvent contained after the reaction can be used as it is. Alternatively, the solvent contained after the reaction can be used as it is, and a solvent can be further added. In addition, when other components are added, they may coexist there. Specific examples of the solvent (B) include propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, ethyl acetate, butyl acetate, isopropyl acetate, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol. Examples thereof include monomethyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol monoethyl ether acetate and diethylene glycol ethyl ether acetate. These may be used alone or in combination of two or more. Among these, glycol ether solvents such as propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate used in the production of the copolymer (A) are preferable.

The blending amount of the solvent (B) in the resin composition or the photosensitive resin composition of the present embodiment is generally 30 to 1000 parts by mass when the total amount of the components excluding the solvent (B) in the composition is 100 parts by mass. Parts, preferably 50 to 800 parts by weight, more preferably 100 to 700 parts by weight. If it is the compounding quantity of this range, it will become a resin composition or a photosensitive resin composition which has suitable viscosity.

[Reactive diluent (C)]
The reactive diluent (C) is not particularly limited, but those containing an ethylenically unsaturated double bond such as a vinyl group and a (meth) acryloyloxy group are preferable. Specific examples thereof include aromatic vinyl monomers such as styrene, α-methylstyrene, α-chloromethylstyrene, vinyltoluene, divinylbenzene, diallylphthalate and diallylbenzenephosphonate; polycarboxylic acids such as vinyl acetate and vinyl adipate. Monomers: methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, β-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, ethylene glycol di (meth) acrylate , Diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylol (Meth) acrylic monomers such as propane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tri (meth) acrylate of tris (hydroxyethyl) isocyanurate; triallyl cyanurate Etc. These may be used alone or in combination of two or more.
Among them, a polyfunctional (meth) acrylate having a plurality of (meth) acryloyloxy groups is preferable, and a polyfunctional (meth) acrylate having three or more (meth) acryloyloxy groups is more preferable.

The blending amount of the reactive diluent (C) in the resin composition of the present embodiment is generally 10 to 90% by mass, preferably 100 to 90% by mass when the total amount of the components excluding the solvent (B) in the composition is 100% by mass. Is 20 to 80% by mass, and more preferably 25 to 70% by mass. When the compounding amount is within this range, the resin composition has an appropriate viscosity.

[Photopolymerization initiator (D)]
The photopolymerization initiator (D) is not particularly limited, but specific examples thereof include benzoin; benzoin alkyl ethers such as benzoin methyl ether and benzoin ethyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1, Acetophenones such as 1-dichloroacetophenone and 4- (1-t-butyldioxy-1-methylethyl) acetophenone; 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; benzopheno Benzophenones such as 4- (1-t-butyldioxy-1-methylethyl) benzophenone and 3,3 ′, 4,4′-tetrakis (t-butyldioxycarbonyl) benzophenone; 2-methyl-1- [4 -(Methylthio) phenyl] -2-morpholino-propan-1-one; 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1; acylphosphine oxides; and xanthones .. These may be used alone or in combination of two or more.

The blending amount of the photopolymerization initiator (D) in the photosensitive resin composition of the present embodiment is 100 parts by mass based on the total amount of the copolymer (A) and the reactive diluent (C) in the photosensitive resin composition. Then, it is generally 0.1 to 30 parts by mass, preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass. A blending amount within this range results in a photosensitive resin composition having appropriate photocurability.

<Compound (G) that generates an acid by heat and / or UV irradiation>
Hereinafter, a compound that generates an acid by heat is abbreviated as “(G-1) thermal acid generator”, and a compound that generates an acid by ultraviolet irradiation is abbreviated as “(G-2) photoacid generator”. There is. The (G-1) thermal acid generator and (G-2) photoacid generator are not particularly limited as long as they can generate an acid by heat and / or ultraviolet irradiation, and examples thereof include an iodonium salt, Examples thereof include onium salts such as sulfonium salts, phosphonium salts and diazonium salts, with sulfonium salts being preferred. Among these, TA-100 and TA-120 manufactured by San-Apro Co., Ltd., which are capable of generating an acid by heating at 100 ° C. or more and available, are preferable as the (G-1) thermal acid generator. As the (G-2) photo-acid generator, a triarylsulfonium salt-based photo-acid generator which has few impurities and is highly sensitive to i-rays is preferable, and among them, CPI-210 series and CPI-100 series manufactured by San Apro Co., Ltd., CPI-300 series and CPI-400 series are more preferable. These (G-1) thermal acid generator and (G-2) photoacid generator may be used alone or in combination of two or more kinds.

The compounding amount of the compound (G) that generates an acid upon irradiation with heat and / or ultraviolet rays is the constitutional unit derived from the epoxy group-containing (meth) acrylate (a-3) used when synthesizing the copolymer (A). Generally, 0.05 to 20 parts by mass, preferably 0.1 to 15 parts by mass, more preferably 1 to 10 parts by mass based on 100 parts by mass of the epoxy group-containing (meth) acrylate (a-3) to be provided. is there. When the content is within this range, it is possible to provide a photosensitive resin composition in which the curing reaction is faster, the curing reaction proceeds under lower temperature conditions, and the storage stability is ensured.

[Colorant (E)]
The colorant (E) is not particularly limited as long as it can be dissolved or dispersed in the solvent (B), and known dyes or pigments can be used. When a dye is used as the colorant (E), it is possible to obtain a colored pattern having a higher brightness than when a pigment is used, and a good alkali developability is exhibited. On the other hand, when a pigment is used as the colorant (E), the heat resistance of the colored pattern is higher than when a dye is used. Dyes and pigments may be used in combination depending on the required performance and the intended pixel color.

"dye"
As the dye, an acid dye having an acidic group such as a carboxy group, from the viewpoint of solubility in a solvent (B) or an alkali developing solution, interaction with other components in the resin composition for a color filter, heat resistance, and the like, It is preferable to use a salt of an acidic dye with a nitrogen compound, a sulfonamide body of an acidic dye, or the like. Specific examples of such dyes include acid alizarin violet N; acid black 1, 2, 24, 48; acid blue 1, 7, 9, 25, 29, 40, 45, 62, 70, 74, 80, 83, 90. , 92, 112, 113, 120, 129, 147; acid chrome violet K; acid Fuchsin; acid green 1, 3, 5, 25, 27, 50; acid orange 6, 7, 8, 10, 12, 50, 51, 52. , 56, 63, 74, 95; acid
red1, 4, 8, 14, 17, 18, 26, 27, 29, 31, 34, 35, 37, 42, 44, 50, 51, 52, 57, 69, 73, 80, 87, 88, 91, 92, 94, 97, 103, 111, 114, 129, 133, 134, 138, 143, 145, 150, 151, 158, 176, 183, 198, 211, 215, 216, 217, 249, 252, 257, 260, 266, 274; acid violet 6B, 7, 9, 17, 19; acid yellow1, 3, 9, 11, 17, 23, 25, 29, 34, 36, 42, 54, 72, 73, 76, 79 , 98, 99, 111, 112, 114, 116; food yellow 3 and derivatives thereof.
Among these, azo, xanthene, anthraquinone or phthalocyanine acid dyes are preferable. These dyes can be used alone or in combination of two or more, depending on the intended color of the pixel.

"Pigment"
Specific examples of the pigment include C.I. I. Pigment Yellow 1, 3, 12, 13, 14, 15, 16, 17, 20, 24, 31, 53, 83, 86, 93, 94, 109, 110, 117, 125, 128, 137, 138, 139, 147, 148, 150, 153, 154, 166, 173, 194, 214 and other yellow pigments; C.I. I. Pigment Orange 13, 31, 36, 38, 40, 42, 43, 51, 55, 59, 61, 64, 65, 71, 73 and the like; orange pigments; I. Pigment Red 9, 97, 105, 122, 123, 144, 149, 166, 168, 176, 177, 180, 192, 209, 215, 216, 224, 242, 254, 255, 264, 265 and the like; C. I. Pigment Blue 15, 15: 3, 15: 4, 15: 6, 60 and other blue pigments; C.I. I. Pigment Violet 1, 19, 23, 29, 32, 36, 38 and the like violet color pigments; C.I. I. Pigment Green 7, 36, 58 and other green pigments; C.I. I. Pigment Brown 23, 25 and the like brown pigments; C.I. I. Pigment Black 1 and 7, black pigments such as carbon black, titanium black and iron oxide. These pigments can be used alone or in combination of two or more, depending on the intended color of the pixel.

When the colorant (E) is blended in the photosensitive resin composition of the present embodiment, the blending amount is generally 5 when the total amount of the components excluding the solvent (B) in the photosensitive resin composition is 100 parts by mass. To 80 parts by mass, preferably 5 to 70 parts by mass, more preferably 10 to 60 parts by mass.

When a pigment is used as the colorant (E), a known dispersant may be added to the photosensitive resin composition from the viewpoint of improving the dispersibility of the pigment. As the dispersant, it is preferable to use a polymer dispersant having excellent dispersion stability over time. Examples of polymer dispersants include urethane dispersants, polyethyleneimine dispersants, polyoxyethylene alkyl ether dispersants, polyoxyethylene glycol diester dispersants, sorbitan aliphatic ester dispersants, and aliphatic modified esters. Examples include a system dispersant. As such a polymer dispersant, EFKA (manufactured by EFKA CHEMICALS BV (EFKA)), Disperbyk (manufactured by Big Chemie), Disparon (manufactured by Kusumoto Kasei Co., Ltd.), and SOLSPERSE (manufactured by Zeneca) are commercially available. You may use what has been. The blending amount of the dispersant in the photosensitive resin composition of the present embodiment may be appropriately set according to the type of pigment used.

[Composition of resin composition]
In the resin composition of the present embodiment, the copolymer (A) and the solvent (B) are blended in such amounts that the total amount of the components excluding the solvent (B) in the resin composition is 100 parts by mass. (A) is 50 to 100 parts by mass, and the solvent (B) is 30 to 1000 parts by mass, preferably 50 to 800 parts by mass, more preferably 100 to 700 parts by mass.

When the resin composition of the present embodiment contains the reactive diluent (C), the blending amounts of the copolymer (A), the solvent (B) and the reactive diluent (C) are the same as those of the solvent in the resin composition. When the total amount of the components excluding (B) is 100 parts by mass, the copolymer (A) is 10 to 90 parts by mass, the solvent (B) is 30 to 1000 parts by mass, and the reactive diluent (C) is 10 to 10 parts by mass. 90 parts by mass, preferably 20 to 80 parts by mass of the copolymer (A), 50 to 800 parts by mass of the solvent (B), and 20 to 80 parts by mass of the reactive diluent (C), More preferably, the copolymer (A) is 30 to 75 parts by mass, the solvent (B) is 100 to 700 parts by mass, and the reactive diluent (C) is 25 to 70 parts by mass.

[Composition of photosensitive resin composition]
The blending amounts of the copolymer (A), the solvent (B), the reactive diluent (C), and the photopolymerization initiator (D) of the photosensitive resin composition of the present embodiment are the same as those in the photosensitive resin composition. When the total amount of the components excluding the solvent (B) is 100 parts by mass, preferably 5 to 80 parts by mass of the copolymer (A), 30 to 1000 parts by mass of the solvent (B), and the reactive diluent (C). Is 10 to 90 parts by mass, the photopolymerization initiator (D) is 0.1 to 30 parts by mass, and more preferably 8 to 70 parts by mass of the copolymer (A) and 50 to 800 parts of the solvent (B). 20 parts by mass of the reactive diluent (C) and 0.5 to 20 parts by mass of the photopolymerization initiator (D), and more preferably 10 to 60 parts by mass of the copolymer (A). Parts, the solvent (B) is 100 to 700 parts by mass, the reactive diluent (C) is 25 to 70 parts by mass, and the photopolymerization initiator (D) is 1 to 15 parts by mass. .

When the photosensitive resin composition of the present embodiment contains the colorant (E), the copolymer (A), the solvent (B), the reactive diluent (C), the photopolymerization initiator (D), the colorant When the total amount of the components excluding the solvent (B) in the photosensitive resin composition is 100 parts by mass, the blending amount of (E) is preferably 5 to 80 parts by mass of the copolymer (A) and the solvent (B). ) Is 30 to 1000 parts by mass, the reactive diluent (C) is 10 to 89 parts by mass, the photopolymerization initiator (D) is 0.1 to 30 parts by mass, and the colorant (E) is 5 to 80 parts by mass. More preferably, the copolymer (A) is 8 to 70 parts by mass, the solvent (B) is 50 to 800 parts by mass, the reactive diluent (C) is 20 to 80 parts by mass, and the photopolymerization initiator (D ) Is 0.5 to 20 parts by mass, the colorant (E) is 5 to 70 parts by mass, and more preferably the copolymer (A) is 10 to 60 parts by mass and the solvent (B). 100-700 parts by weight reactive diluent (C) is 25 to 70 parts by weight, the photopolymerization initiator (D) 1 to 15 parts by mass, the colorant (E) is 10 to 60 parts by weight.

When the photosensitive resin composition of this embodiment contains a photo-acid generator (G), the copolymer (A) of the photosensitive resin composition of this embodiment, a solvent (B), a reactive diluent ( The amounts of C), the photopolymerization initiator (D), and the photoacid generator (G) are preferably, when the total amount of the components excluding the solvent (B) in the photosensitive resin composition is 100 parts by mass. The polymer (A) is 5 to 80 parts by mass, the solvent (B) is 30 to 1000 parts by mass, the reactive diluent (C) is 10 to 90 parts by mass, and the photopolymerization initiator (D) is 0.1 to 30 parts by mass. Parts by weight, 0.001 to 5 parts by weight of the photoacid generator (G), more preferably 8 to 70 parts by weight of the copolymer (A), 50 to 800 parts by weight of the solvent (B), and the reaction 20 to 80 parts by mass of the functional diluent (C), 0.5 to 20 parts by mass of the photopolymerization initiator (D), and 0.01 to 4 parts by mass of the photoacid generator (G). Preferably, the copolymer (A) is 10 to 60 parts by mass, the solvent (B) is 100 to 700 parts by mass, the reactive diluent (C) is 25 to 70 parts by mass, and the photopolymerization initiator (D) is 1 to 15 parts by mass, and the photoacid generator (G) is 0.01 to 2 parts by mass.
Furthermore, when the photosensitive resin composition of the present embodiment contains the colorant (E), the copolymer (A), the solvent (B), the reactive diluent (C), the photopolymerization initiator (D), The amount of the colorant (E) and the photo-acid generator (G) compounded is preferably the copolymer (A) when the total amount of the components excluding the solvent (B) in the photosensitive resin composition is 100 parts by mass. Is 5 to 80 parts by mass, the solvent (B) is 30 to 1000 parts by mass, the reactive diluent (C) is 10 to 89 parts by mass, the photopolymerization initiator (D) is 0.1 to 30 parts by mass, and the colorant. (E) is 5 to 80 parts by mass, the photo-acid generator (G) is 0.001 to 5 parts by mass, and more preferably 8 to 70 parts by mass of the copolymer (A) and the solvent (B). 50 to 800 parts by mass, reactive diluent (C) 20 to 80 parts by mass, photopolymerization initiator (D) 0.5 to 20 parts by mass, colorant (E) 5 to 70 parts by mass, light The amount of the generator (G) is 0.01 to 4 parts by mass, more preferably 10 to 60 parts by mass of the copolymer (A), 100 to 700 parts by mass of the solvent (B), and the reactive diluent (C). ) Is 25 to 70 parts by mass, the photopolymerization initiator (D) is 1 to 15 parts by mass, the colorant (E) is 10 to 60 parts by mass, and the photo-acid generator (G) is 0.01 to 2 parts by mass. is there.

The resin composition of the present embodiment, in addition to the above components, in order to impart predetermined properties, known coupling agents, leveling agents, known additives such as thermal polymerization inhibitors, and known coloring You may mix agents, fillers, dispersants, and the like. The blending amount of these additives is not particularly limited as long as the effects of the present invention are not impaired.

[Method for producing resin composition]
The resin composition of the present embodiment can be produced by mixing the above components using a known mixing device. The photosensitive resin composition of the present embodiment is prepared by first preparing a resin composition containing a copolymer (A) and a solvent (B), and then preparing a reactive diluent (C), a photopolymerization initiator ( It is also possible to mix and produce D). The resin composition can be used for preparing the photosensitive resin composition of the present embodiment, and can also be used for other purposes.

The photosensitive resin composition of the present embodiment obtained as described above is excellent in sensitivity to light and heat, heat-decomposition resistance and heat yellowing, and high-definition cured material excellent in low reflectivity (curing Pattern) can be given. Therefore, the photosensitive resin composition of the present embodiment, various resists, in particular, a microlens surface capable of suppressing reflected light, a substrate incorporated in an image display device capable of suppressing reflection of external light, a color filter, a black matrix. It is suitable for use as a resist used for manufacturing a column spacer, a protective film, and the like. In addition, the photosensitive resin composition of the present embodiment gives a cured film excellent in various properties such as heat decomposition resistance, heat yellowing, high transparency, and low reflectivity, and therefore various coatings, adhesives, printing It is also suitable for use as a binder for inks and the like.

[Registration]
Next, the resist prepared using the photosensitive resin composition of the present invention will be described. The resist of the present invention refers to a cured film obtained from the above photosensitive resin composition. The resist of one embodiment of the present invention includes a glass substrate, a silicon substrate, a polycarbonate substrate, a polyester substrate, a polyamide substrate, a polyamideimide substrate, a polyimide substrate, an aluminum substrate, a printed wiring board, an array substrate, and other substrates on which the present invention is applied. The photosensitive resin composition is applied and the coating film is exposed to light to cure the exposed portion. Then, by baking, a predetermined cured film can be formed on the substrate. The method for applying the photosensitive resin composition is not particularly limited, but a screen printing method, a roll coating method, a curtain coating method, a spray coating method, a spin coating method, a slit coating method or the like can be used. In addition, after applying the photosensitive resin composition, the solvent (B) may be volatilized by heating using a heating means such as a circulation oven, an infrared heater, or a hot plate, if necessary. The heating conditions are not particularly limited and may be appropriately set depending on the type of photosensitive resin composition used. Generally, heating may be performed at a temperature of 50 ° C. to 120 ° C. for 30 seconds to 30 minutes.

The light source used for the exposure is not particularly limited, but a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp and the like can be used.
The amount of exposure is also not particularly limited, and may be appropriately adjusted according to the type of photosensitive resin composition used.

The alkaline aqueous solution used for development is not particularly limited, but an aqueous solution of sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide or the like; an aqueous solution of an amine compound such as ethylamine, diethylamine or dimethylethanolamine; 3 -Methyl-4-amino-N, N-diethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β- Methanesulfonamidoethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline and their water-soluble p-phenylenediamine compounds such as sulfates, hydrochlorides or p-toluenesulfonates Etc. can be used. Among these, it is preferable to use an aqueous solution of a p-phenylenediamine compound. In addition, an antifoaming agent or a surfactant may be added to these aqueous solutions, if necessary. Further, it is preferable to wash with water and dry after the development with the above alkaline aqueous solution.

The baking conditions are not particularly limited, and heat treatment may be performed depending on the type of photosensitive resin composition used. Generally, heating may be performed at 130 to 250 ° C. for 10 to 60 minutes.

A desired colored pattern can be formed by sequentially repeating the above-mentioned coating, exposure, development and baking using the photosensitive resin composition for black matrix and the photosensitive resin composition for pixels. .. In the above, the method for forming a colored pattern by photocuring has been described. However, if a photosensitive resin composition containing a curing accelerator and a known epoxy resin is used instead of the photopolymerization initiator (D), an inkjet method can be used. It is also possible to form a desired colored pattern by applying the coating method and then heating.

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. In this example, all parts and percentages are based on mass unless otherwise specified.

<Measurement method of molecular weight>
The molecular weight (Mw) means a standard polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography (GPC) under the following conditions.
Column: Showdex (registered trademark) LF-804 + LF-804 (manufactured by Showa Denko KK)
Column temperature: 40 ° C
Sample: 0.2% tetrahydrofuran solution of copolymer (A) Developing solvent: Tetrahydrofuran Detector: Differential refractometer (Showdex RI-71S) (Showa Denko KK)
Flow rate: 1 mL / min

<Method of measuring acid value>
According to JIS K6901 5.3.2, the number of mg of potassium hydroxide required to neutralize the acidic component contained in 1 g of the copolymer (A) was measured.
Measuring device: 776 Dosimat (Metrohm)
Mixed indicator: Mixed indicator of bromothymol blue and phenol red

<Method for measuring hydroxyl equivalent>
It is the mass of the polymer per the number of moles of hydroxy groups, and is a calculated value calculated based on the amount of the monomer used.

<Measuring method of epoxy equivalent>
It is the mass of the polymer per the number of moles of the epoxy group and is a calculated value calculated based on the amount of the monomer used.

<Method of measuring refractive index>
The refractive index means the refractive index of the copolymer (A) measured using a refractometer. The refractive index of the resin composition (sample) containing the copolymer (A) and the solvent (B) of the present invention is measured under the following conditions, and then the refractive index of the solvent (B) is measured under the following conditions. Next, the content (solid content) of the copolymer (A) contained in the sample was measured according to JIS K6901 5.11, and the refractive index of the copolymer (A) alone contained in the sample was calculated using the following formula. calculate.
Measuring device: J-357 Automatic Refractometer (Rudolf Research Analytical)
Measurement wavelength: 589 nm
Measurement temperature: 20 ℃
Refractive index of copolymer (A) alone = (refractive index of sample−refractive index of solvent (B)) ÷ solid content × 100 + refractive index of solvent (B) <measurement method of solid content>
The heating residue when the sample obtained in the following synthesis example was heated at 130 ° C. for 2 hours was measured.

<Method of measuring fluorine equivalent>
It is the mass of the polymer per the number of moles of the fluorine atom, and is a calculated value calculated based on the amount of the monomer used.

A production example of a resin composition (sample) containing the copolymer (A) and the solvent (B) of the present invention is shown below.
<Example 1>
"Synthesis of Copolymer (A)"
684.5 g of propylene glycol monomethyl ether acetate was placed in a flask equipped with a stirrer, a dropping funnel, a condenser, a thermometer, and a gas introduction tube, and the mixture was stirred while substituting with nitrogen and heated to 80 ° C. Next, 10.4 g of dicyclopentanyl methacrylate (a-1A), 269.9 g of 2,2,2-trifluoroethyl methacrylate (a-2), 30.2 g of glycidyl methacrylate (a-3), A monomer mixture consisting of 18.3 g of methacrylic acid (a-4) and 36.9 g of 2-hydroxyethyl methacrylate (a-6) was added to 19.4 g of 2,2'-azobis (2,4-dimethylvalero). Nitrile) (polymerization initiator, 5.0 parts by mass with respect to 100 parts by mass of the monomer mixture) was added dropwise to the flask through the dropping funnel. After completion of the dropping, the mixture was stirred at 80 ° C. for 2 hours to carry out a copolymerization reaction to obtain a copolymer (A) of Example 1.

Next, to this copolymer, 30.6 g of propylene glycol monomethyl ether acetate was added as a solvent (B), and sample No. Got 1. Table 1 shows the blending ratio of each monomer when the total of all the monomers is converted to 100 mol%, and the fluorine equivalent, molecular weight, acid value, hydroxyl equivalent, epoxy equivalent, and refractive index of the copolymer (A). ..

<Example 2, Comparative Examples 1 to 3>
"Synthesis of Copolymer (A)"
A copolymer (A) was produced in the same manner as in Example 1 except that the mixing ratios of the monomers shown in Table 1 were used, and propylene glycol monomethyl ether acetate was added as the solvent (B). Got 2-5. Table 1 shows the fluorine equivalent, the molecular weight, the acid value, the hydroxyl equivalent, the epoxy equivalent, and the refractive index of the copolymer (A) contained in each sample.

(Examples 3 to 4, Comparative Examples 4 to 5)
Sample No. 1 to 3, No. 5 was used to prepare a photosensitive resin composition.
<Preparation of transparent photosensitive resin composition>
Sample No. 1 to 3, No. 5 parts by mass of solid content of 100 parts by mass of pentaerythritol tetraacrylate (reactive diluent (C)), 2,2-dimethoxy-2-phenylacetophenone (photopolymerization initiator (D)) 10 parts by mass Was added, and then propylene glycol monomethyl ether acetate was added so that the solvent (B) was 210 parts by mass to prepare a transparent photosensitive resin composition.

(Example 5)
Sample No. 1 was used to prepare a photosensitive resin composition.
<Preparation of transparent photosensitive resin composition>
Sample No. 100 parts by mass of solid content of 1 to 100 parts by mass of pentaerythritol tetraacrylate (reactive diluent (C)), 10 parts by mass of 2,2-dimethoxy-2-phenylacetophenone (photopolymerization initiator (D)) , And CPI-210S (manufactured by San-Apro Co., Ltd.) (photoacid generator (G)) (0.05 parts by mass) were added to prepare a transparent photosensitive resin composition.

Note that the residue of the sample excluding the solvent (propylene glycol monomethyl ether acetate) is defined as “solid content”.

<Pattern formation by transparent photosensitive resin composition>
The transparent photosensitive resin compositions prepared in Examples 3 to 5 and Comparative Examples 4 to 6 were coated on a 5 cm square glass substrate (alkali-free glass substrate) so that the final cured coating film had an average thickness of 2.5 μm. After being spin-coated as described above, the solvent was volatilized by heating at 100 ° C. for 3 minutes. Next, the entire surface of the coating film was exposed with an apparatus (exposure amount: 80 mJ / cm ² ), photocured, and then baked at 230 ° C. for 30 minutes to obtain a transparent resist which was a cured coating film.

<Evaluation of transparent resist>
The transparent resist was evaluated for heat decomposition resistance and heat yellowing.
(1) Evaluation of thermal decomposition resistance Evaluation was carried out by thermogravimetric analysis (TGA) using a sample obtained by cutting out a coating film formed on a glass substrate. In this analysis, this sample was heated to 220 ° C. at a temperature rising rate of 10 ° C./min, held for 2 hours, and then weighed. The weight change rate between the sample after heating and the sample before heating was determined. The weight change rate was measured up to -5.0%, and those with a larger weight change were judged to have poor thermal decomposition resistance.

(2) Evaluation of heat-resistant yellowing
The coating film formed on the glass substrate is left in a dryer at 230 ° C. under a nitrogen gas atmosphere for 1 hour, and the change in color of the coating film before and after the heat treatment (ΔE ^* ab) is manufactured by Nippon Denshoku Industries Co., Ltd. Comparison was made with a color difference meter SE2000.

Table 2 shows the evaluation results of heat decomposition resistance and heat yellowing of the transparent resist.

(Examples 6 to 7, Comparative Examples 6 to 8)
Sample No. A black photosensitive resin composition was prepared using 1 to 5.
<Preparation of black pigment dispersion>
In a SUS container filled with 180 parts by mass of zirconia beads having a diameter of 0.5 mm, 10 parts by mass of carbon black, 34 parts by mass of propylene glycol monomethyl ether acetate, and 6 parts by mass of a dispersant (Disperbyk-manufactured by BYK Japan KK 161) was added and mixed by a paint shaker for 3 hours and dispersed to obtain a black pigment dispersion liquid.

<Preparation of black photosensitive resin composition>
Sample No. 67 parts by mass of dipentaerythritol hexaacrylate (reactive diluent (C)), ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H, per 100 parts by mass of the solid content of 1 to 5 -Carbazol-3-yl-]-,-1- (O-acetyloxime) (photopolymerization initiator (D)) 13 parts by mass, solid content of the black pigment dispersion (colorant (E)) 180 parts by mass After the addition, propylene glycol monomethyl ether acetate was added so that the solvent (B) was 670 parts by mass to prepare a black photosensitive resin composition.

(Example 8)
Sample No. 1 was used to prepare a black photosensitive resin composition.
<Preparation of black pigment dispersion>
A black pigment dispersion liquid was obtained in the same manner as in Example 6.

<Preparation of black photosensitive resin composition>
Sample No. 67 parts by mass of dipentaerythritol hexaacrylate (reactive diluent (C)), ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole, relative to 100 parts by mass of the solid content of 1. -3-yl-]-,-1- (O-acetyloxime) (photopolymerization initiator (D)) 13 parts by mass, black pigment dispersion (colorant (E)) 180 parts by mass, and CPI-210S ( A transparent photosensitive resin composition was prepared by adding 0.05 part by mass of San-Apro Co., Ltd. (photoacid generator (G)).

<Pattern formation with black photosensitive resin composition (with development)>
The black photosensitive resin compositions prepared in Examples 6 to 8 and Comparative Examples 7 to 9 were applied on a 5 cm square glass substrate (alkali-free glass substrate) so that the final cured coating film had an average thickness of 1.0 μm. After being spin-coated as described above, the solvent was volatilized by heating at 100 ° C. for 3 minutes. Next, a line-and-space or dot-pattern photomask was placed on the substrate to expose the coating film (exposure amount 300 mJ / cm ² ), and after photocuring, a 0.2 mass% potassium hydroxide aqueous solution was used. It was developed and further baked at 230 ° C. for 30 minutes to obtain a black resist as a cured coating film.

<Pattern formation with black photosensitive resin composition (no development)>
The black photosensitive resin compositions prepared in Examples 6 to 8 and Comparative Examples 7 to 9 were applied on a 5 cm square glass substrate (alkali-free glass substrate) so that the final cured coating film had an average thickness of 1.0 μm. After being spin-coated as described above, the solvent was volatilized by heating at 100 ° C. for 3 minutes. Next, the entire surface of the coating film was exposed (exposure amount 300 mJ / cm ² ), photocured, and then baked at 230 ° C. for 30 minutes to obtain a black resist as a cured coating film.

<Evaluation of black resist>
The black resist was evaluated for developability, solvent resistance, and reflectance.

(1) Evaluation of solvent resistance The coating film prepared by pattern formation (with development) using the black photosensitive resin composition is immersed in N-methyl-2-pyrrolidone together with the glass substrate for 15 minutes in an oven at 100 ° C. After leaving, the presence or absence of color loss was visually confirmed and evaluated according to the following criteria.
◯: There is no color loss in the pattern x: There is color loss in the pattern

(2) Evaluation of developability In pattern formation (with development) using the black photosensitive resin composition, the time required for the pattern to start to be visible was measured during development with a 0.2 mass% potassium hydroxide aqueous solution. The measurement time was up to 180 seconds, and when the pattern was not visible by then, it was judged that development was not possible.
Further, the development form (how the unexposed portion is removed) was visually confirmed and evaluated according to the following criteria.
◯: The unexposed portion is dissolved in the developing solution ×: The unexposed portion is peeled off

(3) Evaluation of reflectance The reflectance at 550 nm of the coating film prepared by pattern formation (without development) using the black photosensitive resin composition was measured using a spectrophotometer UV-1650PC manufactured by Shimadzu Corporation. ..

Table 3 shows the evaluation results of the developability, solvent resistance, and reflectance of the black resist.

As can be seen from the results of Table 2 and Table 3, in Examples 3 to 5 and Examples 6 to 8, by using the copolymer (A) of the present invention, excellent thermal decomposition resistance, thermal yellowing resistance, A resist exhibiting solvent resistance, developability and low reflectivity was obtained. On the other hand, in Comparative Examples 4 and 5, and Comparative Examples 6 to 8, since the copolymer of the present invention was not used, any resist having insufficient performance was obtained.

From the above, according to the present invention, it is possible to provide a copolymer (A) having excellent alkali developability and an excellent low refractive index while exhibiting photocurability. In addition, the photosensitive resin composition of the present invention can provide a resist that contributes to low reflection and high definition of all electronic material members such as microlenses and image display devices.

Claims

Consisting of a structural unit derived from a polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms and a structural unit derived from a polymerizable monomer (a-1B) represented by the following chemical formula (1) At least one selected from the group;
A structural unit derived from a fluorine-containing (meth) acrylate (a-2) represented by the following chemical formula (2),
A structural unit derived from an epoxy group-containing (meth) acrylate (a-3) and a structural unit derived from an unsaturated carboxylic acid (a-4),
And a structural unit derived from a hydroxy group-containing (meth) acrylate (a-6),
A copolymer (A) having an acid value of 20 KOHmg / g or more.

(X and X ′ in the formula (1) each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 4 carbon atoms, and R 1 and R 2 each independently. A hydrogen atom, a carboxy group, or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and may have a cyclic structure connecting R1 and R2.)

(In the formula (2), R3 represents a hydrogen atom or a methyl group, L represents —O—, —O—CH 2 —CH (OH) —CH 2 —, —O—NH—C (═O) —CH. 2 --CH 2-, each Z independently represents a hydrogen atom, a fluorine atom, a CF 3 group, a C 2 F 5 group, a C 3 F 7 group or a hydroxy group, and n is 0 to It is an integer of 12. However, at least three fluorine atoms are included in the formula (2).
The copolymer (A) according to claim 1, which has a refractive index of less than 1.50.
The copolymer (A) according to claim 1 or 2, wherein the fluorine equivalent of the copolymer (A) is 250 g / mol or less.
The polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms is dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate, and adamantyl. The copolymer (A) according to any one of claims 1 to 3, which contains at least one selected from the group consisting of (meth) acrylates.
A structural unit derived from the polymerizable monomer (a-1A) having a bridged cyclic hydrocarbon group having 10 to 20 carbon atoms and a structural unit derived from the polymerizable monomer (a-1B) represented by the following chemical formula (1). The total ratio of the units is 1 to 40 mol%, the ratio of the constituent units derived from the fluorine-containing (meth) acrylate (a-2) represented by the chemical formula (2) is 9 to 80 mol%, and the epoxy group-containing (meth ) The ratio of the constitutional unit derived from acrylate (a-3) is 5 to 30 mol%,
The proportion of the constitutional unit derived from the unsaturated carboxylic acid (a-4) is 5 to 30 mol%, and the proportion of the constitutional unit derived from the hydroxy group-containing (meth) acrylate (a-6) is 5 to 30 mol%. Item 5. The copolymer (A) according to any one of items 1 to 4.
A resin composition containing the copolymer (A) according to any one of claims 1 to 5 and a solvent (B).
The resin composition according to claim 6, further containing a reactive diluent (C).
Further containing a photopolymerization initiator (D),
The resin composition according to claim 7, wherein the reactive diluent (C) contains an ethylenically unsaturated double bond.
The resin composition according to any one of claims 6 to 8, which further contains a compound (G) which generates an acid when irradiated with heat and / or ultraviolet rays.
Contains a colorant (E),
The resin composition according to any one of claims 6 to 9, wherein the colorant (E) is at least one selected from the group consisting of dyes and pigments.
A resist comprising a cured product of the resin composition according to any one of claims 6 to 10.