JP6795753B2 - Resin material for forming a cured film, method for forming a cured film, cured film, semiconductor element and display element - Google Patents

Description

The present invention relates to a resin material for forming a cured film, a method for forming a cured film, a cured film, a semiconductor element, and a display element.

In recent years, flexible displays such as electronic paper have attracted attention, and as a substrate for flexible displays, a plastic substrate using polyethylene terephthalate or the like has been studied. Since this substrate expands or contracts when heated, lowering the temperature of the manufacturing process is being studied. Above all, it is required to lower the firing temperature in the step of forming a cured film such as an interlayer insulating film, which has the highest temperature in the manufacturing process.

As a material for a cured film capable of lowering the firing temperature, a radiation-sensitive resin composition capable of obtaining a high surface hardness with a small number of steps during pattern formation is used, and for example, a carboxy group and an epoxy group can be used. A radiation-sensitive resin composition containing a copolymer containing the same is known (see JP-A-2001-354822). In such a radiation-sensitive resin composition, the surface hardness as a cured film is obtained by reacting the carboxy group and the epoxy group. However, in the radiation-sensitive resin composition containing the above-mentioned copolymer, the carboxy group and the epoxy group react with each other during storage of the radiation-sensitive resin composition to increase the viscosity. May cause deterioration of sex.

Therefore, curing that has excellent surface hardness and can sufficiently satisfy general properties such as chemical resistance, heat resistance, transparency (high light transmittance) and low dielectric constant (low relative permittivity). There is a demand for a resin composition for forming a cured film that can form a film and has excellent storage stability. As such a material, a composition for forming a cured film containing a copolymer containing a fluorinated alkyl alcohol structure and a crosslinkable group is known (see JP-A-2014-152192). Such a cured film-forming composition is configured to be cured by reacting the fluorinated alkyl alcohol structure with a crosslinkable group such as an epoxy group. However, in this cured film-forming composition, the reactivity of the fluorinated alkyl alcohol structure with the epoxy group is slightly inferior to that of the carboxy group and the epoxy group, so that the cured film can be obtained. It may cause deterioration of heat resistance and chemical resistance.

Japanese Unexamined Patent Publication No. 2001-354822 Japanese Unexamined Patent Publication No. 2014-152192

The present invention has been made based on the above circumstances, and an object of the present invention is to have excellent surface hardness and sufficiently satisfy general properties such as chemical resistance, heat resistance, transparency and low dielectric property. It is an object of the present invention to provide a resin material for forming a cured film which can form a possible cured film and has excellent storage stability, a method for forming a cured film using the resin material, a cured film, a semiconductor element and a display element.

（上記式（１−１）中、Ｒ^１は、水素原子、ハロゲン原子、ヒドロキシ基又は炭素数１〜６のアルコキシ基である。Ｒ^２及びＲ^３は、それぞれ独立して、水素原子、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルコキシ基、炭素数１〜６のアルキル基又はフェニル基である。Ａ^１は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルコキシ基又は炭素数１〜６のアルキル基である。Ａ^１が複数の場合、複数のＡ^１はそれぞれ独立して上記定義を満たす。ｎ１は、０〜４の整数である。＊は、結合部位を示す。
上記式（１−２）中、Ｒ^１、Ｒ^２及びＲ^３は、上記式（１−１）と同義である。Ａ^２は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルコキシ基又は炭素数１〜６のアルキル基である。Ａ^２が複数の場合、複数のＡ^２はそれぞれ独立して上記定義を満たす。ｎ２は、０〜６の整数である。＊は結合位を示す。） The invention made to solve the above problems includes a structural unit having an acidic group (hereinafter, also referred to as “structural unit (I))), a group represented by the following formula (1-1), and the following formula (hereinafter, also referred to as “structural unit (I))). A polymer containing a structural unit having at least one group selected from the groups represented by 1-2) (hereinafter, also referred to as “structural unit (II))” (hereinafter, also referred to as “[A] polymer”). ) Is a resin material for forming a cured film.

(In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independent hydrogen atoms and halogens, respectively. It is an atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a phenyl group. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms or 1 carbon atom. If .A ¹ is more a 6 alkyl groups, each independently plurality of ^{a 1} may satisfy the above definition .n1 is an integer of 0 to 4. * indicates a binding site.
In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site. )

Another invention made to solve the above problems is a method for forming a cured film, which comprises a step of forming a coating film on a substrate using the resin material for forming a cured film and a step of heating the coating film. is there.

Yet another invention made to solve the above problems is a step of forming a coating film on a substrate using the resin material for forming a cured film, a step of irradiating a part of the coating film with radiation, and the radiation. This is a method for forming a cured film, which comprises a step of developing a coating film irradiated with and a step of heating the developed coating film.

Yet another invention made to solve the above problems is a cured film formed from the cured film forming resin material.

Yet another invention made to solve the above problems is a semiconductor device provided with the above-mentioned cured film.

Yet another invention made to solve the above problems is a display element including the above semiconductor element.

The present invention is for forming a cured film having excellent surface hardness, capable of forming a cured film that can sufficiently satisfy general properties such as chemical resistance, heat resistance, transparency, and low dielectric property, and having excellent storage stability. It is possible to provide a resin material, a method for forming a cured film using the resin material, a cured film, a semiconductor element, and a display element. Therefore, the present invention can be suitably used in a manufacturing process of an electronic device such as a flexible display.

The resin material for forming a cured film according to an embodiment of the present invention contains the [A] polymer. The polymer [A] is cured by cross-linking by heating, as will be described later. Therefore, the cured film-forming resin material can be used as a thermosetting resin material for forming a cured film (hereinafter, also referred to as "resin material for forming a cured film (1)"). The material (1) usually does not have radiosensitivity. On the other hand, the cured film-forming resin material is also referred to as, for example, a polymerizable compound having an ethylenically unsaturated bond (hereinafter, also referred to as “[B] polymerizable compound”. ) And a radiation-sensitive polymerization initiator (hereinafter, also referred to as “[C] radiation-sensitive polymerization initiator”), a resin material for forming a cured film having radiation-sensitive properties (hereinafter, “cured film”). It can also be used as a "forming resin material (2)". Hereinafter, each of the cured film forming resin material (1) and the cured film forming resin material (2) will be described.

<Resin material for forming a cured film (1)>
The cured film-forming resin material (1) contains the [A] polymer. Further, the resin material (1) for forming a cured film preferably contains [D] an antioxidant, and may further contain other components as long as the effects of the present invention are not impaired.

<[A] Polymer>
The polymer [A] is at least one selected from the structural unit (I) having an acidic group, the group represented by the following formula (1-1) and the group represented by the following formula (1-2). Includes a structural unit (II) having a group. [A] The polymer may further contain structural units other than the structural unit (I) and the structural unit (II). The polymer [A] may be a copolymer having a structural unit (I) and a structural unit (II), or a polymer having a structural unit (I) and a structural unit (II). It may be a mixture of polymers having. In the polymer [A], the structural unit (I) and the structural unit (II) are considered to be crosslinked and cured by heating, for example, by the following reaction.

According to the cured film-forming resin material (1), a cured film having excellent surface hardness and sufficiently satisfying general properties such as chemical resistance, heat resistance, transparency and low dielectric property is to be formed. Can be done. In particular, by introducing the siloxane structure by the structural unit (II), the heat resistance and transparency of the obtained cured film can be made excellent. Further, as a result of the above reaction being difficult to proceed at room temperature, the cured film-forming resin material (1) has excellent storage stability.

[Structural unit (I)]
The structural unit (I) is a structural unit having an acidic group. The structural unit (I) may be composed of a plurality of types of structural units.

Examples of the acidic group include a carboxy group, a sulfo group, a phenolic hydroxyl group, a phosphoric acid group, a phosphonic acid group, a phosphinic acid group, a sulfonamide group, and a hydroxyalkyl in which a hydrogen atom bonded to a carbon atom is substituted with an electron-withdrawing group. The groups can be mentioned. Examples of the electron attracting group include halogen atoms such as fluorine and chlorine, nitro groups and cyano groups. As the acidic group, a carboxy group, a sulfo group, a phenolic hydroxyl group, a fluorine-containing alcoholic hydroxyl group (hydroxyfluorinated alkyl group), a phosphoric acid group, a phosphonic acid group, a phosphinic acid group and a combination thereof are preferable, and a fluorine-containing alcohol is preferable. The sex hydroxyl group is more preferable. With such an acidic group, the effect of the present invention can be exerted more effectively.

As the fluorine-containing alcoholic hydroxyl group, a group represented by the following formula (2) is preferable. The group represented by the following formula (2) may exhibit better cross-linking reactivity with the group represented by the formula (1-1) or (1-2) of the structural unit (II). it can.

In the above formula (2), R ⁴ is a fluorine atom or a fluorinated alkyl group having 1 to 4 carbon atoms. R ⁵ is a hydrogen atom, a fluorine atom, an alkyl group having 1 to 4 carbon atoms or a fluorinated alkyl group having 1 to 4 carbon atoms.

Examples of the fluorinated alkyl group of 1 to 4 carbon atoms represented by ^{R 4,} difluoromethyl group, trifluoromethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoro Ethyl group, 2,2,3,3-tetrafluoropropyl group, perfluoroethylmethyl group, perfluoropropyl group, 2,2,3,3,4,4-hexafluorobutyl group, perfluorobutyl group, etc. Can be mentioned.

As the R ^4, preferably a fluorinated alkyl group, more preferably a perfluoroalkyl group, a trifluoromethyl group (perfluoromethyl group) is more preferred.

The alkyl group having 1 to 4 carbon atoms represented by ^{R 5,} a methyl group, an ethyl group, n- propyl group, i- propyl, n- butyl group, i- butyl group, sec- butyl group, t -Butyl group and the like can be mentioned. Examples of the fluorinated alkyl group having 1 to 4 carbon atoms represented by R ⁵ include those exemplified in the description of R ⁴ .

The above-mentioned R ^5, a hydrogen atom, a fluorine atom and a fluorinated alkyl group, more preferably a hydrogen atom or a fluorinated alkyl group, more preferably a perfluoroalkyl group, a trifluoromethyl group is particularly preferred.

Further, it is preferable that both R ⁴ and R ⁵ are fluorinated alkyl groups, more preferably both are perfluoroalkyl groups, and further preferably both are trifluoromethyl groups. When the above R ⁴ and R ⁵ are such groups, they become suitable acidic groups, so that a good cross-linking reaction occurs, and various properties of the obtained cured film such as chemical resistance can be further enhanced.

The structural unit (I) includes a structural unit represented by the following formula (3-1), a structural unit represented by the following formula (3-2), a structural unit represented by the following formula (4), and (meta). ) Structural units derived from acrylic acid can be mentioned.

In the above formula (3-1) and (3-2), ^{R 4} and ^{R 5} have the same meanings as ^{R 4} and ^{R 5} in the formula (2). R ⁶ and R ⁷ are independently (n + 1) -valent organic groups. However, in R ⁷ , those having an ester structure (-COO-) at the end on the main chain side are excluded. R is independently a hydrogen atom, a methyl group, a hydroxymethyl group, a cyano group or a trifluoromethyl group. n is an integer of 1 to 5 independently of each other. When n is 2 or more, the plurality of R ⁴ and R ⁵ may be the same or different from each other.

Examples of the (n + 1) -valent organic group represented by R ⁶ and R ⁷ include, for example, a hydrocarbon group having a (n + 1) -valent chain hydrocarbon group having 1 to 20 carbon atoms and a (n + 1) -valent chain hydrocarbon group having 3 to 20 carbon atoms. Examples include n + 1) -valent alicyclic hydrocarbon groups, (n + 1) -valent aromatic hydrocarbon groups having 6 to 20 carbon atoms, or (n + 1) -valent groups in which two or more of these groups are combined. Be done. However, some or all of the hydrogen atoms contained in these groups may be substituted.

Examples of the (n + 1) -valent chain hydrocarbon group having 1 to 20 carbon atoms include a linear or branched alkyl group having 1 to 20 carbon atoms from which n hydrogen atoms have been removed. Examples of the linear or branched alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a 2-methylpropyl group and a 1-methyl group. Examples thereof include a propyl group and a t-butyl group.

Examples of the (n + 1) -valent alicyclic hydrocarbon group having 3 to 20 carbon atoms include a group obtained by removing n hydrogen atoms from a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms. Examples of the monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a norbornyl group and an adamantyl group.

Examples of the (n + 1) -valent aromatic hydrocarbon group having 6 to 20 carbon atoms include a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms from which n hydrogen atoms have been removed. Examples of the monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms include a phenyl group, a tolyl group, and a naphthyl group.

The above R ⁶ and R ⁷ include
Methylene group, ethylene group, propylene group (1,3-propylene group, 1,2-propylene group, etc.), tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group , Undecamethylene group, dodecamethylene group, tridecamethylene group, tetradecamethylene group, pentadecamethylene group, hexadecamethylene group, heptadecamethylene group, octadecamethylene group, nonadecamethylene group, insalen group, 1- Methylene-1,3-propylene group, 2-methyl-1,3-propylene group, 2-methyl-1,2-propylene group, 1-methyl-1,4-butylene group, 2-methyl-1,4- Saturated chain hydrocarbon groups such as butylene group, methylene group, etylidene group, propylidene group, 2-propylidene group;
Cyclobutylene group such as 1,3-cyclobutylene group, cyclopentylene group such as 1,3-cyclopentylene group, cyclohexylene group such as 1,4-cyclohexylene group, 1,5-cyclooctylene group, etc. Monocyclic hydrocarbon ring groups such as cycloalkylene groups such as cyclooctylene groups in
Norbornene group (1,4-norbornene group, 2,5-norbornene group, etc.), adamantylene group (1,5-adamantylene group, 2,6-adamantylene group, etc.), cyclohexanetriyl group (1,3, Polycyclic hydrocarbon group such as 5-cyclohexanetriyl group;
Aromatic hydrocarbon groups such as 1,3-phenylene group and 1,4-phenylene group;
And a group combining these are preferable.

Examples of the ^{R 6,} methylene group, ethylene group, 1,2-propylene group, 2,5-norbornylene group, a 1,4-phenylene group, and 1,3,5-cyclohexanetricarboxylic-yl group is more preferable. As the R ^6, (n + 1) -valent aromatic hydrocarbon group is more preferable. When the above R ⁶ is an aromatic hydrocarbon group, heat resistance and the like can be further improved.

Further, as the R ⁷ , a (n + 1) -valent aromatic hydrocarbon group such as a 1,3-phenylene group or a 1,4-phenylene group is more preferable, and a 1,4-phenylene group is even more preferable. When the above R ⁷ is an aromatic hydrocarbon group, heat resistance and the like can be further improved.

As the R, a hydrogen atom and a methyl group are preferable.

As the above n, 1 and 2 are preferable.

Examples of the structural unit represented by the above formula (3-1) include structural units represented by the following formulas (3-1-1) to (3-1-6), respectively. Further, as the structural unit represented by the above formula (3-2), structural units represented by the following formulas (3-2-1) to (3-2-2) can be mentioned.

In the above formula, R is synonymous with R in the above formulas (3-1) and (3-2). Among these, structural units containing aromatic hydrocarbon groups represented by the formulas (3-1-3), (3-2-1) and (3-2-2) are preferable, and the formula (3-1-1) is preferable. A structural unit in which an aromatic hydrocarbon group represented by 3) and (3-2-1) is substituted with a group represented by -C (CF ₃ ) ₂ OH as an acidic group is more preferable.

In the above formula (4), R'is a hydrogen atom, a methyl group or a trifluoromethyl group. R ^L1 to R ^L5 are each independently a hydrogen atom, a hydroxy group or an alkyl group having 1 to 4 carbon atoms. Y is a single bond, -COO- or -CONH-. p is an integer from 0 to 3. Provided ^that at least one of R L1 ^{to R L5} is a hydroxy group.

The alkyl group having 1 to 4 carbon atoms represented by ^R L1 ^{to R L5,} mention may be made of the group exemplified as the alkyl group having 1 to 4 carbon atoms represented by the ^{R 5.}

Examples of the structural unit represented by the above formula (4) include structural units represented by the following formulas (4-1) to (4-8).

In the above formula, R'and p are synonymous with R'and p in the above formula (4), respectively. Among these, structural units represented by the formulas (4-1) and (4-7) are preferable.

Among these, as the structural unit (I), the structural unit represented by the above formula (3-1) and the structural unit represented by the above formula (3-2) are preferable. Further, the structural unit (I) includes a structural unit represented by the above formula (3-1) or a structural unit represented by the above formula (3-2), and a structural unit derived from (meth) acrylic acid. It is preferable to use in combination with a structural unit having a carboxy group such as. By setting the structural unit (I) to such a structure, various properties such as chemical resistance of the obtained cured film can be further enhanced.

The lower limit of the content ratio of the structural unit (I) is preferably 10% by mass, more preferably 20% by mass, further preferably 30% by mass, and 40% by mass, based on all the structural units constituting the polymer [A]. Mass% is particularly preferred. On the other hand, as the upper limit of the content ratio of the structural unit (I), 80% by mass is preferable, 70% by mass is more preferable, and 60% by mass is further preferable. By setting the content ratio of the structural unit (I) in the above range, the storage stability and various properties of the obtained cured film can be further improved. The content ratio of each structural unit in each polymer can be regarded as the same as the charging ratio (blending ratio) of the monomers corresponding to each structural unit in the synthesis of the [A] polymer.

Among the structural units (I), the lower limit of the content ratio of the structural units having a fluorine-containing alcoholic hydroxyl group, such as the structural units represented by the formulas (3-1) and (3-2), is [ A] 10% by mass is preferable, and 20% by mass is more preferable, based on all the structural units constituting the polymer. On the other hand, as the upper limit, 60% by mass is preferable, 50% by mass is more preferable, and 40% by mass is further preferable.

Among the above structural units (I), the lower limit of the content ratio of the structural unit having a carboxy group such as the structural unit derived from (meth) acrylic acid is set with respect to all the structural units constituting the polymer [A]. 5% by mass is preferable, 10% by mass is more preferable, 15% by mass is further preferable, and 20% by mass is particularly preferable. On the other hand, as the upper limit, 50% by mass is preferable, and 30% by mass is more preferable.

[Structural unit (II)]
The structural unit (II) is a structural unit having at least one group selected from the groups represented by the following formula (1-1) and the groups represented by the following formula (1-2). The structural unit (II) may be composed of a plurality of types of structural units.

In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group, or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independently hydrogen atoms, halogen atoms, hydroxy groups, alkoxy groups having 1 to 6 carbon atoms, and alkyl groups or phenyl groups having 1 to 6 carbon atoms. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ¹ is plural, each independently plurality of A ¹ may satisfy the above definition. n1 is an integer from 0 to 4. * Indicates the binding site.

In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site.

Examples of the halogen atom represented by R ^{1 to} R ³ include a fluorine atom, a chlorine atom, and a bromine atom.

Examples of the alkoxy group having 1 to 6 carbon atoms represented by R ^{1 to} R ³ include a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group and the like.

Examples of the alkyl group having 1 to 6 carbon atoms represented by R ² and R ³ include an alkyl group having 1 to 4 carbon atoms exemplified in the explanation of R ⁵ above.

As the R ^1, preferably an alkoxy group having 1 to 6 carbon atoms, more preferably a methoxy group and an ethoxy group, a methoxy group is more preferred.

As the R ² and R ³ , an alkoxy group having 1 to 6 carbon atoms is preferable, a methoxy group and an ethoxy group are more preferable, and a methoxy group is further preferable.

Examples of the halogen atom represented by A ¹ and A ² , the alkoxy group having 1 to 6 carbon atoms and the alkyl group having 1 to 6 carbon atoms include those exemplified as R ^{1 to} R ³ above, respectively.

The n1 is preferably 0. Further, the n2 is preferably 0.

Examples of the structural unit (II) include a structural unit represented by the following formula (5-1) and a structural unit represented by the following formula (5-2). Among these, the structural unit represented by the following formula (5-2) is preferable from the viewpoint of heat resistance and the like.

In the above formula (5-1) and ^(5-2), R 1 to R ³ have the same meanings as ^R 1 to R ³ in the formula (1-1) and (1-2). R ⁸ and R ⁹ are divalent organic groups each independently having a benzene ring or a naphthalene ring linked to Si. However, in R ⁹ , those having an ester structure (-COO-) at the end on the main chain side are excluded. Each R ^A is independently, a hydrogen atom, a methyl group, a hydroxymethyl group, a cyano group or a trifluoromethyl group.

Examples of the divalent group represented by R ⁸ and R ⁹ include a phenylene group and a naphthylene group, as well as a phenylene group or a naphthylene group, a chain hydrocarbon group, an alicyclic hydrocarbon group and other linking groups. The group linked with is mentioned. However, some or all of the hydrogen atoms contained in these groups may be substituted with substituents. Examples of the substituent include the groups represented by the above A ¹ and A ² . The chain hydrocarbon group and the alicyclic hydrocarbon group are examples of (n + 1) valent organic groups represented by R ⁶ and R ⁷ in the above formulas (3-1) and (3-2). Among the listed ones, a divalent group can be mentioned.

As the R ⁸ and R ⁹ , a phenylene group and a naphthylene group are more preferable, and a p-phenylene group is further preferable. That, ^Si in the formula ^{(5-1) (R 1 R 2} R 3) -R 8 - and ^{Si (R 1 R 2 R 3} ) -R 9 - is the formula (1-1) or (1- It is preferably a group represented by 2).

As the ^RA , a hydrogen atom and a methyl group are preferable.

Examples of the structural unit represented by the above formula (5-1) include structural units represented by the following formulas (5-1-1) to (5-1-2). Examples of the structural unit represented by the above formula (5-2) include structural units represented by the following formulas (5-2-1) to (5-2-2).

In the above formula, ^{R A} has the same meaning as ^{R A} in the above formula (5-1) and (5-2).

The lower limit of the content ratio of the structural unit (II) is preferably 10% by mass, more preferably 20% by mass, based on all the structural units constituting the polymer [A]. On the other hand, as the upper limit, 70% by mass is preferable, and 50% by mass is more preferable. By setting the content ratio of the structural unit (II) within the above range, various properties of the obtained cured film, storage stability, and the like can be further enhanced.

[Structural unit (III)]
The polymer [A] preferably further has a structural unit having a crosslinkable group (hereinafter, also referred to as “structural unit (III)”). [A] When the polymer has the structural unit (III), the surface hardness and the like of the obtained cured film can be further increased.

The crosslinkable group refers to a group other than an acidic group and a group represented by the above formula (1-1) or (1-2) and which can be covalently bonded to another group or the like. Examples of the crosslinkable group include an oxylanyl group (1,2-epoxy structure), an oxetanyl group (1,3-epoxy structure), a cyclic carbonate group, a methylol group (hydroxymethyl structure), a (meth) acryloyl group and the like. Be done.

Examples of the structural unit (III) containing an oxylanyl group include structural units represented by the following formulas (6-1) to (6-5). Examples of the structural unit (III) containing an oxetanyl group include structural units represented by the following formulas (6-6) to (6-9). Examples of the structural unit (III) containing a cyclic carbonate group include structural units represented by the following formulas (6-10) to (6-14). Examples of the structural unit (III) containing a methylol group include a structural unit represented by the following formula (6-15).

In the above formula, R ^B is a hydrogen atom, a methyl group or a trifluoromethyl group.

Examples of the structural unit (III) containing the (meth) acryloyl group include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and dipropylene di (meth). Meta) acrylate, tripropylene di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl Di (meth) acrylate compounds such as glycol di (meth) acrylate and tripropylene glycol diacrylate;
Tri (meth) acrylate compounds such as tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate;
Tetra (meth) acrylate compounds such as pentaerythritol tetra (meth) acrylate;
Examples thereof include structural units derived from monomeric compounds such as penta (meth) acrylate compounds such as dipentaerythritol penta (meth) acrylate.

As the crosslinkable group, an oxylanyl group, an oxetanyl group, a methylol group and a combination thereof are preferable, an oxylanyl group, a methylol group and a combination thereof are more preferable, and an oxylanyl group is further preferable. By having such a crosslinkable group, the heat resistance and chemical resistance of the formed cured film can be further enhanced.

The lower limit of the content ratio of the structural unit (III) is preferably 1% by mass, more preferably 5% by mass, still more preferably 10% by mass, based on all the structural units constituting the polymer [A]. On the other hand, as the upper limit, 70% by mass is preferable, 50% by mass is more preferable, 30% by mass is further preferable, and 25% by mass is particularly preferable. By setting the content ratio of the structural unit (III) in the above range, it is possible to further enhance various properties of the obtained cured film while maintaining high storage stability.

[Structural unit (IV)]
[A] The polymer is a structural unit other than the structural units (I) to (III), and is a structural unit derived from a (meth) acrylic acid ester having a hydroxy group (hereinafter, “structural unit (IV)”). Can have.

Examples of the structural unit (IV) include structural units represented by the following formulas (7-1) to (7-3).

In the above formula, ^RC is a hydrogen atom, a methyl group or a trifluoromethyl group.

The content ratio of the structural unit (IV) can be, for example, 1% by mass or more and 50% by mass or less with respect to all the structural units constituting the polymer [A].

[Structural unit (V)]
[A] The polymer may have other structural units (hereinafter, also referred to as “structural unit (V)”) other than the structural units (I) to (IV). [A] Since the polymer has a structural unit (V), the cured film-forming resin material (1) adjusts the glass transition temperature of the resin, and has a melt flow property during thermosetting and a cured film obtained. Mechanical strength and chemical resistance can be improved.

Examples of the structural unit (V) include structural units represented by the following formulas (8-1) to (8-10).

In the above formula, ^RD is a hydrogen atom, a methyl group or a trifluoromethyl group. ^RM is a hydrogen atom or a methyl group. s is an integer from 1 to 10. Among these, as the structural unit (V), the structural units represented by the formulas (8-1), (8-6) to (8-8) and (8-10) are preferable.

Examples of the monomer compound giving the structural unit (V) include (meth) acrylic acid chain alkyl ester, (meth) acrylic acid cyclic alkyl ester, (meth) acrylic acid aryl ester, unsaturated dicarboxylic acid diester, and uncyclonized. Saturated compounds, maleimide compounds, unsaturated aromatic compounds and conjugated diene compounds, unsaturated compounds having a tetrahydrofuran skeleton, furan skeleton, tetrahydropyran skeleton, pyran skeleton or a skeleton represented by the following formula (9), and other unsaturated compounds. Examples include structural units derived from compounds and the like.

In the above formula (9), ^{R M} and s have the same meanings as ^{R M} and s in the formula (8-9).

Examples of the (meth) acrylic acid chain alkyl ester include methyl acrylate, ethyl acrylate, n-butyl acrylate, sec-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, and isodecyl acrylate. Acrylic acid chain alkyl esters such as n-lauryl acrylate, tridecyl acrylate, n-stearyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, isodecyl methacrylate, n-lauryl methacrylate, tridecyl methacrylate, n-methacrylate Examples thereof include methacrylic acid chain alkyl esters such as stearyl.

Examples of the (meth) acrylic acid cyclic alkyl ester include cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo acrylate [5.2.1.0 ^2,6 ] decane-8-yl, and tricyclo acrylate [5]. 2.1.0 ^2,6 ] Acrylic acid cyclic alkyl esters such as decane-8-yloxyethyl and isobolonyl acrylate;
Cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo methacrylate [5.2.1.0 ^2,6 ] decane-8-yl, tricyclo methacrylate [5.2.1.0 ^2,6 ] decane-8 − Methacrylic acid cyclic alkyl esters such as yloxyethyl and isobolonyl methacrylate can be mentioned.

Examples of the (meth) acrylic acid aryl ester include phenyl acrylate. Acrylic acid aryl esters such as benzyl acrylate;
Examples thereof include methacrylic acid aryl esters such as phenyl methacrylate and benzyl methacrylate.

Examples of the unsaturated dicarboxylic acid diester include diethyl maleate, diethyl fumaric acid, and diethyl itaconic acid.

Examples of the bicyclounsaturated compound include bicyclo [2.2.1] hept-2-ene, 5-methylbicyclo [2.2.1] hept-2-ene, and 5-ethylbicyclo [2.2.1]. ] Hept-2-ene, 5-methoxybicyclo [2.2.1] hept-2-ene, 5-ethoxybicyclo [2.2.1] hept-2-ene, 5,6-dimethoxybicyclo [2. 2.1] hept-2-ene, 5,6-diethoxybicyclo [2.2.1] hept-2-ene, 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-Cyclohexyloxycarbonylbicyclo [2.2.1] hept-2-ene, 5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene, 5,6-di (t-butoxycarbonyl) bicyclo [ 2.2.1] Hept-2-ene, 5,6-di (cyclohexyloxycarbonyl) bicyclo [2.2.1] Hept-2-ene, 5- (2'-hydroxyethyl) bicyclo [2.2] .1] Hept-2-ene, 5,6-dihydroxybicyclo [2.2.1] hept-2-ene, 5,6-di (hydroxymethyl) bicyclo [2.2.1] hept-2-ene , 5,6-di (2'-hydroxyethyl) bicyclo [2.2.1] hept-2-ene, 5-hydroxy-5-methylbicyclo [2.2.1] hept-2-ene, 5- Examples thereof include hydroxy-5-ethylbicyclo [2.2.1] hept-2-ene and 5-hydroxymethyl-5-methylbicyclo [2.2.1] hept-2-ene.

Examples of the maleimide compound include N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N- (4-hydroxyphenyl) maleimide, N- (4-hydroxybenzyl) maleimide, and N-succinimidyl-3-maleimidebenzoate. , N-succinimidyl-4-maleimidebutyrate, N-succinimidyl-6-maleimide caproate, N-succinimidyl-3-maleimide propionate, N- (9-acridinyl) maleimide and the like.

Examples of the unsaturated aromatic compound include styrene, α-methylstyrene, vinyltoluene, p-methoxystyrene, α-methyl-p-hydroxystyrene and the like.

Examples of the conjugated diene compound include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene and the like.

Examples of the unsaturated compound having a tetrahydrofuran skeleton include 2-methacryloyloxy-propionic acid tetrahydrofurfuryl ester, 3- (meth) acryloyloxy tetrahydrofuran-2-one, and (meth) acrylate tetrahydrofurfuryl.

Examples of the unsaturated compound having a furan skeleton include 2-methyl-5- (3-furyl) -1-penten-3-one, furfuryl (meth) acrylate, and 1-furan-2-butyl-3-ene. -2-one, 1-furan-2-butyl-3-methoxy-3-en-2-one, 6- (2-furyl) -2-methyl-1-hexen-3-one, 6-furan-2 -Il-hex-1-en-3-one, acrylate-2-furan-2-yl-1-methyl-ethyl ester, 6- (2-furyl) -6-methyl-1-hepten-3-one And so on.

Examples of the unsaturated compound containing the tetrahydropyran skeleton include (tetrahydropyran-2-yl) methyl methacrylate and 2,6-dimethyl-8- (tetrahydropyran-2-yloxy) -oct-1-en-3-. On, 2-methacrylic acid tetrahydropyran-2-yl ester, 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one and the like can be mentioned.

Examples of the unsaturated compound having a pyran skeleton include 4- (1,4-dioxa-5-oxo-6-heptenyl) -6-methyl-2-pyran and 4- (1,5-dioxa-6-oxo). -7-octenyl) -6-methyl-2-pyran and the like.

Examples of the other unsaturated compounds include (meth) acrylonitrile, vinyl chloride, vinylidene chloride, (meth) acrylamide, vinyl acetate and the like.

Among these, examples of the monomer compound giving the structural unit (V) include a methacrylic acid chain alkyl ester, a cyclic alkyl methacrylate ester, a maleimide compound, a tetrahydrofuran skeleton, a furan skeleton, a tetrahydropyran skeleton, and a pyran skeleton. An unsaturated compound having a skeleton represented by (9), an unsaturated aromatic compound and an acrylic acid cyclic alkyl ester are preferable, and styrene, methyl methacrylate, t-butyl methacrylate and methacrylic acid are preferable from the viewpoint of copolymerization reactivity and the like. N-lauryl acid, tricyclomethacrylate [5.2.1.0 ^2,6 ] decane-8-yl, p-methoxystyrene, 2-methylcyclohexyl acrylate, N-phenylmaleimide, N-cyclohexylmaleimide, (meth) ) Tetrahydrofurfuryl acrylate, polyethylene glycol (n = 2-10) mono (meth) acrylate and 3- (meth) acryloyloxy tetrahydrofuran-2-one are more preferred.

The lower limit of the content ratio of the structural unit (V) is preferably 1% by mass, more preferably 3% by mass, based on all the structural units constituting the polymer [A]. On the other hand, as the upper limit, 50% by mass is preferable, and 30% by mass is more preferable. By setting the content ratio of the structural unit (V) within the above range, chemical resistance and the like can be effectively improved.

The polymer [A] has structural units (I) to (III), and the structural unit (I) has a structural unit represented by the above formula (3-1) or (3-2) and a carboxy group. It is preferable that the structural unit (II) is a structural unit represented by the above formula (5-2), and the structural unit (III) is a structural unit having an oxylanyl group or a polymeric group. Further, at this time, it is preferable that R ⁴ and R ⁵ in the above formulas (3-1) and (3-2) are perfluoroalkyl groups. Further, at this time, it is preferable that the content ratio of the structural unit having a carboxy group in the [A] polymer is relatively high (for example, 15% by mass or more and 50% by mass or less). [A] When the polymer has such a structural unit, the heat resistance, transparency, surface hardness, low dielectric property, etc. of the obtained cured film can be particularly improved.

<[A] Polymer synthesis method>
The polymer [A] can be produced, for example, by polymerizing a monomer corresponding to each predetermined structural unit in an appropriate solvent using a radical initiator. In general, the compounding ratio of each monomer at the time of polymerization is the same as the content ratio of the corresponding structural unit in the obtained [A] polymer. Specific synthetic methods include (1) a method of dropping a solution containing a monomer and a radical initiator into a reaction solvent or a solution containing a monomer to carry out a polymerization reaction, and (2) a monomer. A method in which a solution containing a radical initiator and a solution containing a radical initiator are separately added dropwise to a solution containing a reaction solvent or a monomer to carry out a polymerization reaction, (3) a plurality of types containing each monomer. It is preferable to synthesize the solution and the solution containing the radical initiator separately by a method such as a method of dropping the solution into a solution containing a reaction solvent or a monomer and causing a polymerization reaction.

The reaction temperature in these methods may be appropriately determined depending on the initiator type. It can usually be 30 ° C to 180 ° C. The dropping time varies depending on conditions such as the reaction temperature, the type of initiator, and the monomer to be reacted, but is usually 30 minutes to 8 hours. Further, the total reaction time including the dropping time also varies depending on the conditions like the dropping time, but is usually 30 minutes to 8 hours.

Examples of the radical initiator used in the above polymerization include azobisisobutyronitrile (AIBN), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), and 2,2'-azobis (2). -Cyclopropylpropionitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylpropionitrile) and the like. These initiators may be used alone or in combination of two or more.

The polymerization solvent is not limited as long as it is a solvent other than a solvent that inhibits polymerization (nitrobenzene having a polymerization prohibition effect, a mercapto compound having a chain transfer effect, etc.) and can dissolve the monomer. Examples of the polymerization solvent include alcohol solvents, ether solvents, ketone solvents, amide solvents, ester-lactone solvents, nitrile solvents and the like. These solvents may be used alone or in combination of two or more.

The polymer obtained by the polymerization reaction can be recovered by the reprecipitation method. That is, after the polymerization reaction is completed, the target polymer is recovered as a powder by putting the polymer solution into the reprecipitation solvent. As the reprecipitation solvent, alcohols, alkanes and the like can be used alone or in combination of two or more. In addition to the reprecipitation method, the polymer can be recovered by removing low molecular weight components such as monomers and oligomers by a liquid separation operation, a column operation, an ultrafiltration operation, or the like. When the polymerization solvent is the same as the solvent of the resin material (1) for forming a cured film prepared, the obtained polymer solution can be used as it is, or a solvent can be added to the obtained polymer solution to form a cured film. It may be used for the preparation of the resin material (1) for use.

[A] In the polymerization reaction for producing a polymer, a molecular weight adjusting agent can be used to adjust the molecular weight. Examples of the molecular weight modifier include halogenated hydrocarbons such as chloroform and carbon tetrabromide; mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, and thioglycolic acid; dimethyl. Xanthogens such as xanthogen sulfide and diisopropyl xanthogen disulfide; turpinolene, α-methylstyrene dimer and the like can be mentioned.

The polystyrene-equivalent weight average molecular weight (Mw) of the polymer by gel permeation chromatography (GPC) is not particularly limited, but is preferably 1,000 or more and 30,000 or less. The ratio (Mw / Mn) of the Mw of the polymer [A] to the polystyrene-equivalent number average molecular weight (Mn) by GPC is preferably 1 or more and 3 or less.

The content of the [A] polymer in the resin material (1) for forming a cured film is not particularly limited, but the lower limit of the content of the [A] polymer in the total solid content is preferably 50% by mass. 70% by mass is more preferable, and 90% by mass is further preferable. On the other hand, this upper limit may be 100% by mass. By setting the content of the [A] polymer in the resin material (1) for forming a cured film within the above range, various properties of the obtained cured film can be more effectively enhanced.

<[D] Antioxidant>
[D] The antioxidant is a component capable of decomposing radicals generated by exposure or heating or peroxides generated by oxidation to prevent the bond of polymer molecules from breaking. As a result, the obtained cured film is prevented from being oxidatively deteriorated over time, and for example, a change in the film thickness of the cured film can be suppressed.

[D] Examples of the antioxidant include a compound having a hindered phenol structure, a compound having a hindered amine structure, a compound having an alkyl phosphite structure, a compound having a thioether structure, and the like. Among these, as the [D] antioxidant, a compound having a hindered phenol structure is preferable.

Examples of the compound having a hindered phenol structure include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and thiodiethylenebis [3- (3,5-di-). tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, tris- (3,5-di-t-butyl-4-hydroxy) Benzyl) -isocyanurate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N'-hexane-1,6 -Diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide), 3,3', 3', 5', 5'-hexa-tert-butyl-a, a', a '-(Mesitylen-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, 4,6-bis (dodecylthiomethyl) -o-cresol, ethylene Bis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate, hexamethylene bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] , 1,3,5-Tris [(4-tert-butyl-3-hydroxy-2,6-kisilyl) methyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H)- Trion, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazine-2-ylamine) phenol, 1,3,5-trimethyl-2,4 Examples thereof include 6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene and 2,6-di-t-butyl-4-cresol.

Commercially available products of the compound having the hindered phenol structure include, for example, ADEKA STUB AO-20, AO-30, AO-40, AO-50, AO-60, AO-70, and AO-80. AO-330 (above, ADEKA), sumilizerGM, GS, MDP-S, BBM-S, WX-R, GA-80 (above, Sumitomo Chemical), IRGANOX1010, 1035, 1076 , 1098, 1135, 1330, 1726, 1425WL, 1520L, 245, 259, 3114, 565, IRGAMOD295 (above, BASF), Yoshinox BHT, BB, 2246G, 425. , 250, 930, SS, TT, 917, 314 (above, API Corporation) and the like.

Among the compounds having a hindered phenol structure, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-trimethyl-2,4,6-tris (3,5-Di-t-Butyl-4-hydroxybenzyl) benzene and 2,6-di-t-butyl-4-cresol are more preferred.

The content of the [D] antioxidant is preferably 0.001 part by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the [A] polymer. [D] By setting the content of the antioxidant in the above range, it is possible to effectively suppress the oxidative deterioration of the obtained cured film over time.

<Other ingredients>
Examples of other components that the cured film-forming resin material (1) may contain include, for example, [E] surfactant, [F] adhesive aid, and the like, in addition to the solvent described below. In the resin material (1) for forming a cured film, each of the above components may be used alone or in combination of two or more.

<[E] Surfactant>
[E] The surfactant is a component that improves the film-forming property. [E] Examples of the surfactant include a fluorine-based surfactant, a silicone-based surfactant, and other surfactants.

As the fluorine-based surfactant, a compound having a fluoroalkyl group and / or a fluoroalkylene group at at least one of the terminal, main chain and side chain is preferable, and for example, 1,1,2,2-tetrafluoro-n. -Octyl (1,1,2,2-tetrafluoro-n-propyl) ether, 1,1,2,2-tetrafluoro-n-octyl (n-hexyl) ether, hexaethylene glycol di (1,1,2,2, 2,3,3-hexafluoro-n-pentyl) ether, octaethylene glycol di (1,1,2,2-tetrafluoro-n-butyl) ether, hexapropylene glycol di (1,1,2,2,3) 3-Hexafluoro-n-pentyl) ether, octapropylene glycol di (1,1,2,2-tetrafluoro-n-butyl) ether, sodium perfluoro-n-dodecanesulfonate, 1,1,2,2,3 3-Hexafluoro-n-decane, 1,1,2,2,8,8,9,9,10,10-decafluoro-n-dodecane, sodium fluoroalkylbenzenesulfonate, sodium fluoroalkylphosphate, fluoroalkylcarboxylic acid Sodium acid, diglycerin tetrakis (fluoroalkyl polyoxyethylene ether), fluoroalkyl ammonium iodide, fluoroalkyl betaine, other fluoroalkyl polyoxyethylene ethers, perfluoroalkyl polyoxyethanol, perfluoroalkyl alkoxylate, fluorocarboxylic acid Alkyl esters and the like can be mentioned.

Commercially available products of the above-mentioned fluorine-based surfactant include, for example, BM-1000, BM-1100 (above, BM CHEMIE), Megafuck F142D, F172, F173, F183, F178, F191, F471, F476 (above, Dainippon Ink and Chemicals), Florard FC-170C, -171, -430, A-431 (above, Sumitomo 3M Ltd.), Surfron S-112, -113, -131, -141, -145, -382, Surflon SC-101, -102, -103, -104, -105, -106 (above, Asahi Glass Co., Ltd.), Ftop EF301, 303, 352 (above, Shin-Akita Kaseisha), Surfactant FT-100, -110, -140A, -150, -250, -251, -300, -310, -400S, FTX -218, -251 (above, Neos) and the like.

Examples of commercially available silicone-based surfactants include Torre Silicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, and SZ-6032. SF-8428, DC-57, DC-190 (above, Toray Dow Corning Silicone), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4452 ( As mentioned above, GE Toshiba Silicone Co., Ltd.), Organosiloxane Polymer KP341 (Shin-Etsu Chemical Co., Ltd.) and the like can be mentioned.

Examples of the other surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene-n-octylphenyl ether, and polyoxyethylene-n. -Polyoxyethylene aryl ethers such as nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate can be mentioned.

Examples of commercially available products of the above other surfactants include (meth) acrylic acid-based copolymer Polyflow No. 57, No. 95 (above, Kyoeisha Chemical Co., Ltd.) and the like can be mentioned.

The content of the [E] surfactant is preferably 0.01 parts by mass or more and 3 parts by mass or less with respect to 100 parts by mass of the [A] polymer. [E] By setting the content of the surfactant in the above range, the film-forming property can be effectively improved.

<[F] Adhesive aid>
[F] The adhesive aid is a component that improves the adhesiveness between the obtained cured film and the substrate. [F] As the adhesion aid, a functional silane coupling agent having a reactive functional group such as a carboxy group, a methacryloyl group, a vinyl group, an isocyanate group, and an oxylanyl group is preferable.

Examples of the functional silane coupling agent include trimethoxysilyl benzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, and γ-glycidoxy. Examples thereof include propyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane.

The content of the [F] adhesive aid is preferably 0.01 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the [A] polymer.

<Preparation method of resin material (1) for forming a cured film>
The cured film-forming resin material (1) can be prepared by mixing the polymer [A] and, if necessary, other components in a predetermined ratio, and preferably dissolving it in an appropriate solvent. The prepared resin material (1) for forming a cured film is preferably filtered through, for example, a filter having a pore size of about 0.2 μm.

As the solvent used for preparing the cured film-forming resin material (1), a solvent in which each component contained in the cured film-forming resin material (1) is uniformly dissolved or dispersed and does not react with the above-mentioned components is used. Used. Examples of such a solvent include alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, hydrocarbon solvents and the like.

Examples of the alcohol-based solvent include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, tert-butanol, n-pentanol, and i-pen as monoalcohol-based solvents. Tanol, 2-methylbutanol, sec-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n -Octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-hepta Decyl alcohol, furfuryl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol, etc .;
As polyhydric alcohol-based solvents, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2 , 4-Heptanediol, 2-ethyl-1,3-hexanediol, Diethylene glycol, Dipropylene glycol, Triethylene glycol, Tripropylene glycol, etc .;
As a polyhydric alcohol partially ether-based solvent, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethyl Butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol Examples thereof include monomethyl ether, dipropylene glycol monoethyl ether and dipropylene glycol monopropyl ether.

Examples of the ether solvent include diethyl ether, dipropyl ether, dibutyl ether, diphenyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, tetrahydrofuran and the like.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, and methyl-n. Examples thereof include -hexyl ketone, di-i-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone, 2,4-pentandione, acetonylacetone and acetophenone.

Examples of the amide solvent include N, N'-dimethylimidazolidinone, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide. , N-methylpropionamide, N-methylpyrrolidone and the like.

Examples of the ester solvent include methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate and acetic acid. 3-methoxybutyl, 3-methyl-3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, methyl acetoacetate, acetoacetate Ethyl, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl acetate ether, ethylene glycol mono-n-butyl acetate ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n acetate -Propyl ether, diethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl acetate ether, propylene glycol monobutyl acetate ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoacetate Ethyl ether, glycol diacetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate , N-amyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate and the like.

Examples of the above-mentioned hydrocarbon-based solvent include n-pentane, i-pentane, n-hexane, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane, as aliphatic hydrocarbon-based solvents. n-octane, i-octane, cyclohexane, methylcyclohexane, etc .;
Aromatic hydrocarbon solvents include benzene, toluene, xylene, mesitylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propylbenzene, i-propylbenzene, diethylbenzene, i-butylbenzene, triethylbenzene, di-i-propylbenzene. , N-amylnaphthalene and the like.

Further, the solvent may further contain a high boiling point solvent such as caproic acid, caprylic acid, ethylene carbonate and propylene carbonate.

<Method of forming a cured film (1)>
The method (1) for forming a cured film according to an embodiment of the present invention is
(1) A step of forming a coating film on a substrate using the resin material (1) for forming a cured film (hereinafter, also referred to as "step (A1)"), and (2) a step of heating the coating film (2) Hereinafter, it is also referred to as "process (A2)")
To be equipped.

Since the cured film forming resin material (1) has the above-mentioned properties, according to the cured film forming method (1), general heat resistance, chemical resistance, transmittance, relative permittivity, etc. are generally used. It is possible to form a cured film that sufficiently satisfies the above-mentioned characteristics and has excellent surface hardness. Hereinafter, each step will be described in detail.

[Step (A1)]
In this step, a coating film is formed on the substrate by using the cured film forming resin material (1). Specifically, the resin material (1) for forming the cured film in the form of a solution is applied to the surface of the substrate, and preferably prebaking is performed to remove the solvent to form a coating film. Examples of the substrate include a glass substrate, a silicon substrate, a plastic substrate, and a substrate on which various metal thin films are formed on the surface thereof. Examples of the plastic substrate include resin substrates made of plastics such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether sulfone, polycarbonate, and polyimide.

As the coating method, for example, an appropriate method such as a spray method, a roll coating method, a rotary coating method (spin coating method), a slit die coating method, a bar coating method, and an inkjet method can be adopted. Among these, as the coating method, a spin coating method, a bar coating method and a slit die coating method are preferable. The pre-baking conditions vary depending on the type of each component, the usage ratio, and the like, but can be, for example, about 30 seconds to 10 minutes at 60 ° C to 130 ° C. The film thickness of the coating film to be formed is preferably 0.1 μm or more and 8 μm or less as a value after prebaking.

[Process (A2)]
In this step, the coating film is cured by heating. The heating method is not particularly limited, but heating can be performed using a heating device such as an oven or a hot plate. The heating temperature in this step is preferably 200 ° C. or lower. Since heating at such a low temperature is possible, the method (1) for forming the cured film can be suitably used for forming a cured film such as an interlayer insulating film on a plastic substrate of a flexible display. The heating temperature is more preferably 120 ° C. or higher and 180 ° C. or lower. The heating time varies depending on the type of heating equipment, but is, for example, 5 minutes or more and 40 minutes or less when heat treatment is performed on a hot plate, and 30 minutes or more and 80 minutes or less when heat treatment is performed in an oven. be able to. In this way, a cured film such as a target interlayer insulating film can be formed on the substrate.

<Resin material for forming a cured film (2)>
The cured film-forming resin material (2) contains a [A] polymer, a [B] polymerizable compound, and a [C] radiation-sensitive polymerization initiator. Further, the resin material (2) for forming a cured film may contain a [D] antioxidant as a suitable component. Further, the cured film-forming resin material (2) may contain other components as long as the effects of the present invention are not impaired.

Since the resin material (2) for forming a cured film contains the [A] polymer, the [B] polymerizable compound, and the [C] radiation-sensitive polymerization initiator, the portion irradiated with radiation (exposed portion). ) Is cured by polymerization, and parts other than the exposed part (unexposed part) can be dissolved and removed by development with an alkaline developer to form a pattern, which is a negative type radiation-sensitive resin composition having so-called negative type characteristics. is there. Therefore, the cured film-forming resin material (2) can form a patterned cured film. Hereinafter, each component will be described in detail.

<[A] Polymer>
[A] The polymer is a polymer containing a structural unit (I) and a structural unit (II). Further, the [A] polymer preferably contains a structural unit (III), and may contain a structural unit (IV) and a structural unit (V). The [A] polymer in the cured film-forming resin material (2) can be the same as the [A] polymer in the above-mentioned cured film-forming resin material (1).

[A] Since the polymer has the structural unit (I) and the structural unit (II), the cured film-forming resin material (2) is excellent in the same manner as the cured film-forming resin material (1) described above. It has a surface hardness, can form a cured film that can sufficiently satisfy general properties such as chemical resistance, heat resistance, transparency, and low dielectric property, and is excellent in storage stability. In addition, the cured film-forming resin material (2) can exhibit good solubility in an alkaline developer in an unexposed portion due to the presence of the acidic group of the structural unit (I). The polymer [A] may have two or more types of each structural unit.

[Structural unit (I)]
The structural unit (I) is a structural unit having an acidic group. Since this structural unit (I) is the same as the structural unit (I) in the polymer [A] of the above-mentioned resin material for forming a cured film (1), detailed description thereof will be omitted.

The lower limit of the content ratio of the structural unit (I) in the [A] polymer of the cured film forming resin material (2) is preferably 10% by mass with respect to all the structural units constituting the [A] polymer. , 20% by mass is more preferable, 30% by mass is further preferable, and 40% by mass is particularly preferable. On the other hand, as the upper limit of the content ratio of the structural unit (I), 80% by mass is preferable, 70% by mass is more preferable, and 60% by mass is further preferable. By setting the content ratio of the structural unit (I) in the above range, the storage stability and various properties of the obtained cured film can be further improved. Further, by setting the content ratio of the structural unit (I) in the above range, good developability and the like can be exhibited.

A structural unit having a fluorine-containing alcoholic hydroxyl group, such as the structural units represented by the above formulas (3-1) and (3-2) in the [A] polymer of the cured film-forming resin material (2). As the lower limit of the content ratio, 10% by mass is preferable, and 20% by mass is more preferable with respect to all the structural units constituting the polymer [A]. On the other hand, as the upper limit, 60% by mass is preferable, 50% by mass is more preferable, and 40% by mass is further preferable.

The lower limit of the content ratio of the structural unit having a carboxy group such as the structural unit derived from (meth) acrylic acid in the [A] polymer of the resin material for forming a cured film (2) is the [A] polymer. 5% by mass is preferable, 10% by mass is more preferable, 15% by mass is further preferable, and 20% by mass is particularly preferable with respect to all the structural units. On the other hand, as the upper limit, 50% by mass is preferable, and 30% by mass is more preferable.

[Structural unit (II)]
The structural unit (II) is a structural unit having at least one group selected from the group represented by the above formula (1-1) and the group represented by the above formula (1-2). Since this structural unit (II) is the same as the structural unit (II) in the [A] polymer of the above-mentioned resin material for forming a cured film (1), detailed description thereof will be omitted.

The lower limit of the content ratio of the structural unit (II) in the [A] polymer of the cured film forming resin material (2) is preferably 10% by mass with respect to all the structural units constituting the [A] polymer. , 20% by mass is more preferable. On the other hand, as the upper limit, 70% by mass is preferable, and 50% by mass is more preferable. By setting the content ratio of the structural unit (II) within the above range, various properties and storage stability of the obtained cured film can be further enhanced. Further, by setting the content ratio of the structural unit (II) in the above range, a sufficient cross-linking reaction occurs between the structural unit (I) and the structural unit (II) in the [A] polymer, and thus development is performed. Adhesion can be improved.

[Structural unit (III)]
The structural unit (III) is a structural unit having a crosslinkable group. [A] When the polymer has the structural unit (III), the surface hardness of the obtained cured film, the development adhesion, and the like can be improved. Since this structural unit (III) is the same as the structural unit (III) in the [A] polymer of the above-mentioned resin material for forming a cured film (1), detailed description thereof will be omitted.

The lower limit of the content ratio of the structural unit (III) in the [A] polymer of the cured film forming resin material (2) is preferably 1% by mass with respect to all the structural units constituting the [A] polymer. 5, 5% by mass is more preferable, and 10% by mass is further preferable. On the other hand, as the upper limit, 70% by mass is preferable, 50% by mass is more preferable, 30% by mass is further preferable, and 25% by mass is particularly preferable. By setting the content ratio of the structural unit (III) in the above range, it is possible to further enhance various properties such as hardness and development adhesion of the obtained cured film while maintaining high storage stability.

[Structural unit (IV)]
The structural unit (IV) is a structural unit other than the structural units (I) to (III) and is a structural unit derived from a (meth) acrylic acid ester having a hydroxy group. [A] When the polymer has the structural unit (IV), the alkali developability can be controlled and the residue can be suppressed. Since this structural unit (IV) is the same as the structural unit (IV) in the polymer [A] of the above-mentioned resin material for forming a cured film (1), detailed description thereof will be omitted.

The lower limit of the content ratio of the structural unit (IV) in the [A] polymer of the cured film forming resin material (2) is preferably 1% by mass with respect to all the structural units constituting the [A] polymer. 5, 5% by mass is more preferable. On the other hand, as the upper limit, 50% by mass is preferable, and 20% by mass is more preferable. By setting the content ratio of the structural unit (IV) in the above range, it is possible to improve the alkali developability and the like while maintaining high storage stability.

[Structural unit (V)]
The structural unit (V) is a structural unit other than the structural units (I) to (IV). [A] Since the polymer has a structural unit (V), the cured film-forming resin material (2) adjusts the glass transition temperature of the resin, and has alkali developability, melt flow property during thermosetting, and curing. The mechanical strength and chemical resistance of the film can be improved. Since this structural unit (V) is the same as the structural unit (V) in the polymer [A] of the above-mentioned resin material for forming a cured film (1), detailed description thereof will be omitted.

The lower limit of the content ratio of the structural unit (V) in the [A] polymer of the cured film forming resin material (2) is preferably 1% by mass with respect to all the structural units constituting the [A] polymer. 3, 3% by mass is more preferable. On the other hand, as the upper limit, 50% by mass is preferable, and 30% by mass is more preferable. By setting the content ratio of the structural unit (V) within the above range, chemical resistance and the like can be effectively improved.

<[A] Polymer synthesis method>
As the [A] polymer of the cured film-forming resin material (2), the same method as the method for synthesizing the [A] polymer in the cured film-forming resin material (1) described above can be applied.

The polystyrene-equivalent weight average molecular weight (Mw) of the polymer [A] in the cured film-forming resin material (2) by gel permeation chromatography (GPC) is not particularly limited, but is 1,000 or more and 30,000 or less. preferable. The ratio (Mw / Mn) of the Mw of the polymer [A] to the polystyrene-equivalent number average molecular weight (Mn) by GPC is preferably 1 or more and 3 or less.

The content of the [A] polymer in the resin material (2) for forming a cured film is not particularly limited, but the lower limit of the content of the [A] polymer in the total solid content is preferably 40% by mass. 50% by mass is more preferable, and 60% by mass is further preferable. On the other hand, this upper limit is preferably 90% by mass, more preferably 80% by mass. By setting the content of the [A] polymer in the resin material (2) for forming a cured film within the above range, various properties of the obtained cured film can be more effectively enhanced while having good sensitivity and the like. And so on.

<[B] Polymerizable compound>
[B] The polymerizable compound is a compound having an ethylenically unsaturated bond. The [B] polymerizable compound may be used alone or in combination of two or more.

The [B] polymerizable compound is not particularly limited as long as it is a polymerizable compound having an ethylenically unsaturated bond, and is, for example, ω-carboxypolycaprolactone mono (meth) acrylate, 2- (2'-vinyloxyethoxy) ethyl. Monofunctional (meth) acrylate compounds such as (meth) acrylate; ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tetraethylene glycol di (Meta) acrylate, Polyethylene glycol di (meth) acrylate, Polypropylene glycol di (meth) acrylate, Bisphenoxyethanol full orange (meth) acrylate, Dimethylol tricyclodecandi (meth) acrylate, 2-Hydroxy-3- (meth) Acryloyloxypropyl methacrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tri (2- (Meta) acryloyloxyethyl) phosphate, ethylene oxide-modified dipentaerythritol hexaacrylate, succinic acid-modified pentaerythritol triacrylate, linear alkylene group and alicyclic structure, and two or more isocyanates. A polyfunctional compound such as a urethane (meth) acrylate compound obtained by reacting a compound having a group with a compound having one or more hydroxyl groups in the molecule and having 3 to 5 (meth) acrylate groups. Examples thereof include (meth) acrylate compounds.

[B] Commercially available products of the polymerizable compound include, for example, Aronix M-400, M-402, M-405, M-450, M-1310, M-1600, M-1960, and M. -7100, M-8030, M-8060, M-8100, M-8530, M-8560, M-9050, Aronix TO-1450, TO-1382 (above, Toagosei Co., Ltd.);
KAYARAD DPHA, DPCA-20, DPCA-30, DPCA-60, DPCA-120, MAX-3510 (above, Nippon Kayaku Co., Ltd.);
Viscoat 295, 300, 360, GPT, 3PA, 400 (above, Osaka Organic Chemical Industry Co., Ltd.);
As a urethane acrylate compound, New Frontier R-1150 (Daiichi Kogyo Seiyaku Co., Ltd.);
KAYARAD DPHA-40H, UX-5000 (above, Nippon Kayaku Co., Ltd.);
UN-9000H (Negami Kogyo Co., Ltd.);
Aronix M-5300, M-5600, M-5700, M-210, M-220, M-240, M-270, M-6200, M-305, M-309, same M-310, M-315 (above, Toagosei);
KAYARAD HDDA, KAYARAD HX-220, HX-620, R-526, R-167, R-604, R-684, R-551, R-712, UX-2201, UX-2301 , UX-3204, UX-3301, UX-4101, UX-6101, UX-7101, UX-8101, UX-0937, MU-2100, MU-4001 (above, Nippon Kayaku Co., Ltd.);
Art Resin UN-99000PEP, UN-9200A, UN-7600, UN-333, UN-1003, UN-1255, UN-6060PTM, UN-6060P (above, Negami Kogyo Co., Ltd.);
SH-500B Viscoat 260, 312, 335HP (above, Osaka Organic Chemical Industry Co., Ltd.) and the like can be mentioned.

[B] The polymerizable compound preferably has at least one carboxy group in the same molecule. As a result, it is possible to improve the crosslinkability and reduce the development residue in the unexposed portion. Examples of the [B] polymerizable compound having at least one carboxy group in the same molecule include ω-carboxypolycaprolactone mono (meth) acrylate and succinic acid-modified pentaerythritol triacrylate.

The lower limit of the content of the [B] polymerizable compound is preferably 10 parts by mass and more preferably 30 parts by mass with respect to 100 parts by mass of the [A] polymer. On the other hand, as the upper limit, 200 parts by mass is preferable, and 100 parts by mass is more preferable. [B] By setting the content of the polymerizable compound in the above range, the cured film-forming resin material (2) forms a cured film having excellent adhesion and sufficient surface hardness even at a low exposure amount. can do.

<[C] Radiation Sensitive Polymerization Initiator>
The [C] radiation-sensitive polymerization initiator is a component that produces an active species capable of initiating the polymerization of the [B] polymerizable compound in response to radiation. [C] Examples of the radiation-sensitive polymerization initiator include an oxime ester compound, an acetophenone compound, and a biimidazole compound. The [C] radiation-sensitive polymerization initiator may be used alone or in combination of two or more.

Examples of the oxime ester compound include ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (O-acetyloxime) and 1,2-octanedione. -1- [4- (Phenylthio) -2- (O-benzoyloxime)], 1- [9-ethyl-6-benzoyl-9H-carbazole-3-yl] -octane-1-one oxime-O-acetate, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -ethane-1-one oxime-O-benzoate, 1- [9-n-butyl-6- (2-ethyl) Benzoyl) -9H-carbazole-3-yl] -ethane-1-one oxime-O-benzoate, etanone-1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylbenzoyl) -9H-carbazole-3 -Il] -1- (O-acetyloxime), Etanone-1- [9-ethyl-6- (2-methyl-4-tetrahydropyranylbenzoyl) -9H-carbazole-3-yl] -1- (O) -Acetyloxime), Etanone-1- [9-ethyl-6- (2-methyl-5-tetrahydrofuranylbenzoyl) -9H-carbazole-3-yl] -1- (O-acetyloxime), Etanone-1- [9-Ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl} -9H-carbazole-3-yl] -1- (O-acetyloxime) and the like Examples thereof include O-acyloxime compounds. Among these, as the oxime ester compound, etanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (O-acetyloxime), 1, 2 − Octandion-1- [4- (phenylthio) -2- (O-benzoyloxime)], Etanone-1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylmethoxybenzoyl) -9H-carbazole) -3-yl] -1- (O-acetyloxime) and ethanone-1- [9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl} -9H-carbazole-3-yl] -1- (O-acetyloxime) is preferred.

Examples of the acetophenone compound include an α-aminoketone compound and an α-hydroxyketone compound.

Examples of the α-aminoketone compound include 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane-1-one and 2-dimethylamino-2- (4-methylbenzyl) -1-(. Examples thereof include 4-morpholin-4-yl-phenyl) -butane-1-one, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one and the like.

Examples of the α-hydroxyketone compound include 1-phenyl-2-hydroxy-2-methylpropane-1-one and 1- (4-i-propylphenyl) -2-hydroxy-2-methylpropane-1-one. , 4- (2-Hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenyl ketone and the like.

As the acetophenone compound, an α-aminoketone compound is preferable, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl-phenyl) -butane-1-one, and 2 -Methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one is more preferable.

Examples of the biimidazole compound include 2,2'-bis (2-chlorophenyl) -4,4', 5,5'-tetrakis (4-ethoxycarbonylphenyl) -1,2'-biimidazole, 2,2. '-Bis (2-chlorophenyl) -4,4', 5,5'-Tetraphenyl-1,2'-biimidazole, 2,2'-bis (2,4-dichlorophenyl) -4,4', 5 , 5'-Tetraphenyl-1,2'-biimidazole, 2,2'-bis (2,4,6-trichlorophenyl) -4,4', 5,5'-tetraphenyl-1,2'- Examples thereof include biimidazole. Among these, 2,2'-bis (2-chlorophenyl) -4,4', 5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis (2,4-dichlorophenyl) ) -4,4', 5,5'-tetraphenyl-1,2'-biimidazole, and 2,2'-bis (2,4,56-trichlorophenyl) -4,4', 5,5' -Tetraphenyl-1,2'-biimidazole is preferred, 2,2'-bis (2,4-dichlorophenyl) -4,4', 5,5'-tetraphenyl-1,2'-biimidazole is more preferred. preferable.

[C] Commercially available products of the radiosensitizing polymerization initiator include, for example, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one (Irgacure 907), 2-dimethylamino-2-. (4-Methylbenzyl) -1- (4-morpholin-4-yl-phenyl) -butane-1-one (Irgacure 379), 1,2-octanedione-1- [4- (phenylthio) -2- (O-Benzyl oxime)] (Irgacure OXE01), Etanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (O-acetyloxime) (Irgacure OXE02) ) (The above is Ciba Specialty Chemicals Co., Ltd.) and the like.

The lower limit of the content of the [C] radiation-sensitive polymerization initiator is preferably 0.1 part by mass, more preferably 0.5 part by mass, and 2 parts by mass with respect to 100 parts by mass of the [A] polymer. More preferred. On the other hand, as the upper limit, 40 parts by mass is preferable, 20 parts by mass is more preferable, and 10 parts by mass is further preferable. [C] By setting the content of the radiation-sensitive polymerization initiator within the above range, the cured film-forming resin material (2) can be a cured film having sufficient surface hardness and adhesion even at a low exposure amount. It can be formed and so on.

Further, it is preferable that the [C] radiation-sensitive polymerization initiator is an oxime ester compound, and the lower limit of the content of the oxime ester compound is 0.1 part by mass with respect to 100 parts by mass of the [A] polymer. It is more preferably 0.5 parts by mass, and even more preferably 2 parts by mass. The upper limit of the content of the oxime ester compound is preferably 20 parts by mass, more preferably 10 parts by mass, and even more preferably 5 parts by mass with respect to 100 parts by mass of the polymer [A]. .. As a result, it is possible to efficiently form a cured film having sufficient surface hardness and adhesion even at a low exposure amount.

<[D] Antioxidant>
[D] The antioxidant is a component capable of decomposing radicals generated by exposure or heating or peroxides generated by oxidation to prevent the bond of polymer molecules from breaking. As the [D] antioxidant in the cured film-forming resin material (2), the [D] antioxidant in the cured film-forming resin material (1) described above can be applied. By containing the [D] antioxidant in the cured film-forming resin material (2), the obtained cured film can be prevented from oxidative deterioration over time, and for example, changes in the film thickness of the cured film can be suppressed. it can. The [D] antioxidant may be used alone or in combination of two or more.

The content of the [D] antioxidant in the cured film-forming resin material (2) is preferably 0.001 part by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the [A] polymer. [D] By setting the content of the antioxidant in the above range, it is possible to effectively suppress the oxidative deterioration of the obtained cured film over time.

<Other ingredients>
Examples of other components that the cured film-forming resin material (2) may contain include, in addition to solvents, [E] surfactants, [F] adhesive aids, and the like. As each of the other components, those described as the components contained in the above-mentioned resin material for forming a cured film (1) can be applied.

<Preparation method of resin material (2) for forming a cured film>
In the cured film-forming resin material (2), the [A] polymer, the [B] polymerizable compound, the [C] radiation-sensitive polymerization initiator, and other components, if necessary, are mixed in a predetermined ratio. , Preferably can be prepared by dissolving in a suitable solvent. As the solvent used for preparing the cured film-forming resin material (2), for example, the same solvent as the solvent exemplified in the above-mentioned description of the method for preparing the cured film-forming resin material (1) can be applied. .. The prepared resin material (2) for forming a cured film is preferably filtered through, for example, a filter having a pore size of about 0.2 μm.

<Method of forming a cured film (2)>
The method (2) for forming a cured film according to an embodiment of the present invention is
(1) A step of forming a coating film on a substrate using the cured film forming resin material (2) (hereinafter, also referred to as "step (B1)").
(2) A step of irradiating a part of the coating film with radiation (hereinafter, also referred to as "step (B2)").
(3) A step of developing the coating film irradiated with the radiation (hereinafter, also referred to as "step (B3)"), and (4) a step of heating the developed coating film (hereinafter, "step (B4)"). Also called)
To be equipped.

Since the cured film forming resin material (2) has the above-mentioned properties, according to the cured film forming method (2), heat resistance, chemical resistance, transmittance, relative permittivity, etc. It is possible to form a cured film that sufficiently satisfies general properties and has excellent surface hardness. Further, according to the cured film forming method (2), it is possible to develop with good sensitivity and to obtain a cured film having excellent development adhesion. Hereinafter, each step will be described in detail.

[Step (B1)]
In this step, a coating film is formed on the substrate by using the cured film forming resin material (2). Specifically, the solution of the cured film-forming resin material (2) is applied to the surface of the substrate, and the solvent is preferably removed by prebaking to form a coating film. The substrate and coating method can be the same as those described in the step (A1) of the cured film forming method (1).

[Process (B2)]
In this step, a part of the coating film is irradiated with radiation. Specifically, the coating film formed in the step (B1) is irradiated with radiation through a mask having a predetermined pattern. Examples of the radiation used at this time include ultraviolet rays, far ultraviolet rays, X-rays, charged particle beams, and the like.

Examples of the ultraviolet rays include g-line (wavelength 436 nm) and i-line (wavelength 365 nm). Examples of far ultraviolet rays include KrF excimer laser light and the like. Examples of X-rays include synchrotron radiation and the like. Examples of the charged particle beam include an electron beam and the like. Among these radiations, ultraviolet rays are preferable, and among the ultraviolet rays, radiation containing g-rays, h-rays and / or i-rays is more preferable. The exposure amount of radiation, 0.1 J / ^{m 2} or more 10,000 J / ^{m 2} or less.

[Step (B3)]
In this step, the coating film irradiated with the above radiation is developed. Specifically, the coating film irradiated with radiation in the step (B2) is developed with a developing solution to remove the irradiated portion of the radiation. Examples of the developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, diethylaminoethanol, di-n-propylamine, triethylamine, and methyl. Diethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5,4,0] -7-undecene, 1,5-diazabicyclo Examples thereof include an aqueous solution of an alkali (basic compound) such as [4,5,0] -5-nonane. Further, an aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant to the alkaline aqueous solution, or an alkaline aqueous solution containing a small amount of various organic solvents capable of dissolving the cured film-forming resin material (2). May be used as a developing solution.

As the developing method, for example, an appropriate method such as a liquid filling method, a dipping method, a rocking dipping method, and a shower method can be adopted. The developing time varies depending on the composition of the cured film-forming resin material (2), but can be, for example, 30 seconds or more and 120 seconds or less. After the developing step, the patterned coating film is rinsed by washing with running water, and then the entire surface is irradiated with radiation (post-exposure) from a high-pressure mercury lamp or the like to remain in the coating film [C. ] It is preferable to perform a decomposition treatment of the radiation-sensitive polymerization initiator. The exposure amount in the post-exposure is preferably 2,000 J / m ² or more and 5,000 J / m ² or less.

[Process (B4)]
In this step, the developed coating film is heated. Specifically, the coating film is cured by heat-treating (post-baking) the coating film using a heating device such as a hot plate or an oven that heats the coating film developed in the step (B3). The heating temperature and heating time in this step can be the same as those described in step (A2) of the cured film forming method (1). In this way, a patterned coating film corresponding to the desired cured film such as an interlayer insulating film can be formed on the substrate.

<Cured film>
The cured film according to one embodiment of the present invention is formed from the cured film-forming resin material (cured film-forming resin material (1) or cured film-forming resin material (2)). The method for forming the cured film is not particularly limited, but it can be preferably formed by using the above-mentioned method for forming the cured film (1) or the method for forming the cured film (2). Since the cured film is formed from the resin material for forming the cured film, it has excellent surface hardness and can sufficiently satisfy general properties such as chemical resistance, heat resistance, transmittance and relative permittivity. Since the cured film has the above characteristics, it is suitable as, for example, an interlayer insulating film for a display element, a spacer, a protective film, a coloring pattern for a color filter, and the like.

<Semiconductor element>
The semiconductor device according to the embodiment of the present invention includes the cured film. This cured film is used, for example, as an interlayer insulating film, a spacer, a protective film, a coloring pattern for a color filter, or the like that insulates wiring between wirings in the semiconductor element. The semiconductor device can be formed by using a known method. Since the semiconductor element includes the cured film, it can be suitably used for electronic devices such as display elements, LEDs, and solar cells.

<Display element>
The display element according to the embodiment of the present invention includes the semiconductor element. Since the display element includes a semiconductor element having the cured film, it satisfies the general characteristics required for practical use as a display element. Examples of the display element include a liquid crystal display element and the like. In the liquid crystal display element, for example, two TFT array substrates having a liquid crystal alignment film formed on the surface are arranged so as to face each other on the liquid crystal alignment film side via a sealant provided on the periphery of the TFT array substrate. A liquid crystal is filled between these two TFT array substrates. The TFT array substrate has wirings arranged in layers, and the wirings are insulated by the cured film as an interlayer insulating film.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. The measurement method of each physical property value is shown below.

[Weight average molecular weight (Mw) and number average molecular weight (Mn)]
Mw and Mn were measured by gel permeation chromatography (GPC) under the following conditions. The molecular weight distribution (Mw / Mn) was calculated from the obtained Mw and Mn.
Equipment: Showa Denko GPC-101
GPC column: GPC-KF-801, GPC-KF-802, GPC-KF-803 and GPC-KF-804 of Shimadzu GLC Co., Ltd. are combined. Mobile phase: tetrahydrofuran Column temperature: 40 ° C.
Flow velocity: 1.0 mL / min Sample concentration: 1.0 mass%
Sample injection volume: 100 μL
Detector: Differential Refractometer Standard Material: Monodisperse Polystyrene

<[A] Synthesis of polymer>
The monomer compounds used in the synthesis of the polymers of each example and comparative example are shown below.

[Monomer compound giving structural unit (I)]
Monomer compounds (I-1) to (I-8) represented by the following formulas (I-1) to (I-8), and monomer compounds (I-9) to (I-11), respectively.

（Ｉ−９）：メタクリル酸ｐ−ヒドロキシフェニル（４−ヒドロキシフェニルメタクリレート）
（Ｉ−１０）：α−メチル−ｐ−ヒドロキシスチレン
（Ｉ−１１）：メタクリル酸

(I-9): p-Hydroxyphenyl methacrylate (4-hydroxyphenyl methacrylate)
(I-10): α-methyl-p-hydroxystyrene (I-11): methacrylic acid

[Monomer compound giving structural unit (II)]
Monomer compounds (II-1) to (II-4) represented by the following formulas (II-1) to (II-4), respectively.

Further, in the comparative synthesis example, the monomer compound (ii-1) represented by the following (ii-1) was used as the monomer compound corresponding to the monomer compound giving the structural unit (II).

[Monomer compound giving structural unit (III)]
Monomer compounds (III-1) to (III-15) represented by the following formulas (III-1) to (III-15)

[Monomer compound giving structural unit (IV)]
(IV-1): Hydroxyethyl methacrylate (2-hydroxyethyl methacrylate)

[Monomer compound giving structural unit (V)]
(V-1): Styrene (V-2): Methyl methacrylate (V-3): N-cyclohexylmaleimide (V-4): Tetrahydrofurfuryl methacrylate (V-5): Tricyclo methacrylate [5.2] .1.0 ^2,6 ] Decane-8-il

[Synthesis Example 1] (Synthesis of Polymer (A-1))
A flask equipped with a cooling tube and a stirrer was charged with 7 parts by mass of 2,2'-azobis (2,4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether. Next, 30 parts by mass of the monomer compound (I-1) giving the structural unit (I), 22 parts by mass of (I-11), and 30 parts by mass of the monomer compound (II-1) giving the structural unit (II). 18 parts by mass of the monomer compound (III-1) giving the structural unit (III) as well as the parts were charged. Then, nitrogen substitution was performed, the temperature of the solution was raised to 70 ° C. while gently stirring, and the temperature was maintained for 4 hours for polymerization to obtain a polymer solution containing the polymer (A-1). .. The solid content concentration of this polymer solution was 30.4% by mass, the Mw of the polymer (A-1) was 8,000, and the molecular weight distribution (Mw / Mn) was 2.3.

[Synthesis Examples 2 to 47 and Comparative Synthesis Examples 1 to 4] (Synthesis of Polymers (A-2) to (A-47) and (a-1) to (a-4))
The same procedure as in Synthesis Example 1 was carried out except that the monomer compounds of the types and amounts shown in Table 1 below were used, and the polymers (A-2) to (A-47) and (a-1) to ( a-4) was synthesized. The solid content concentration of each of the obtained polymer solutions and the Mw and Mw / Mn of each polymer were equivalent to the values of the above-mentioned polymer (A-1). The blanks in Table 1 indicate that the corresponding monomer compound was not blended.

<Preparation of resin material (1) for forming a cured film>
[Example 1]
[A] After adding diethylene glycol methyl ethyl ether as a solvent to a polymer solution containing 100 parts by mass (solid content) of (A-6) as a polymer so that the solid content concentration becomes 30% by mass, The resin material (1) for forming a cured film of Example 1 was prepared by filtering with a polymer filter having a pore size of 0.2 μm.

[Examples 2 to 3 and Comparative Examples 1 to 4]
The same operation as in Example 1 was carried out except that the component [A] was the type and blending amount shown in Table 2, and each of the cured film-forming resin materials (1) of Examples 2 to 3 and Comparative Examples 1 to 4 was used. Prepared. In addition, "-" in Table 2 indicates that the evaluation described later was not performed.

<Preparation of resin material (2) for forming a cured film>
The [B] polymerizable compound, [C] radiation-sensitive polymerization initiator, and [D] antioxidant used in the preparation of each cured film-forming resin material (2) are shown below.

[[B] Polymerizable compound]
(B-1): Dipentaerythritol hexaacrylate

[[C] Radiation Sensitive Polymerization Initiator]
(C-1): Etanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (O-acetyloxime) (Irgacure OXE02, Ciba Specialty. Chemicals)

[[D] Antioxidant]
(D-1): Pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], (ADEKA's "ADEKA STAB AO-60")

[Example 4]
[A] Polymer solution containing 100 parts by mass (solid content) of (A-1) as a polymer, [B] 50 parts by mass of (B-1) as a polymerizable compound, [C] Radiation-sensitive polymerization Add 5 parts by mass of (C-1) as an initiator and 0.5 parts by mass of (D-1) as an antioxidant and mix them so that the solid content concentration becomes 30% by mass. After adding diethylene glycol methyl ethyl ether as a solvent, the resin material (2) for forming a cured film of Example 4 was prepared by filtering with a polymer filter having a pore size of 0.2 μm.

[Examples 5 to 50 and Comparative Examples 5 to 8]
The same operation as in Example 4 was carried out except that the component [A] was the type and blending amount shown in Table 3, and each of the cured film forming resin materials (2) of Examples 5 to 50 and Comparative Examples 5 to 8 was used. Prepared.

<Evaluation>
The prepared resin materials (1) and (2) for forming a cured film were used and evaluated according to the following evaluation method. The evaluation results are shown in Tables 2 and 3.

[Storage stability]
The viscosity (V ₁ ) of each cured film-forming resin material was measured, and each cured film-forming resin material was left in an oven at 40 ° C. for 1 week. The viscosity (V ₂ ) after heating was measured, and the viscosity change rate (%) was calculated from the following formula and used as an index of storage stability.
Viscosity change rate (%) = {(V _2- V ₁ ) / V ₁ } x 100 (%)
The viscosity change rate is classified into A: viscosity change rate of less than 5%, B: viscosity change rate of 5% or more and less than 10%, C: viscosity change rate of 10% or more and less than 15%, and D: viscosity change rate of 15% or more. In the case of A or B, the storage stability was evaluated as good, and in the case of C or D, it was evaluated as poor. The viscosity was measured at 25 ° C. using an E-type viscometer (“VISCONIC ELD.R” manufactured by Toki Sangyo).

[sensitivity]
After applying each cured film-forming resin material on a silicon substrate using a spinner, it was prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The obtained coating film was irradiated with a predetermined amount of ultraviolet rays by a mercury lamp through a pattern mask having a line-and-space pattern having a width of 10 μm. Next, a developing solution consisting of a 2.38% by mass aqueous solution of tetramethylammonium hydroxide was used to develop the product at 25 ° C. for 60 seconds, and then washed with ultrapure water for 1 minute. At this time, the minimum ultraviolet irradiation amount capable of forming a line-and-space pattern having a width of 10 μm was measured. When this measured value is less than 700 J / m ² , the sensitivity can be evaluated as good, and when it is 700 J / m ² or more, it can be evaluated as defective.

[Development adhesion]
After applying each cured film-forming resin material on a silicon substrate using a spinner, it was prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The obtained coating film was irradiated with ultraviolet rays of 1,000 J / m ² by a mercury lamp through a pattern mask having a line-and-space pattern having a width of 10 μm. Next, a developing solution consisting of a 2.38% by mass aqueous solution of tetramethylammonium hydroxide was used to develop the product at 25 ° C. for 60 seconds, and then washed with ultrapure water for 1 minute under running water. Then, the presence or absence of peeling of the line-and-space pattern having a width of 10 μm was observed with a microscope to determine the development adhesion. At this time, depending on the degree of peeling, A: no peeling, B: slightly peeled, C: partially peeled, D: fully peeled, and in the case of A or B, the development adhesion is good, C. Or, in the case of D, it was evaluated as defective.

[chemical resistance]
After applying each cured film-forming resin material on a silicon substrate using a spinner, it was prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The obtained coating film was irradiated with ultraviolet rays by a mercury lamp so that the integrated irradiation amount was 1,000 J / m ² . Next, this silicon substrate was heated at 200 ° C. for 30 minutes on a hot plate, and the film thickness (T1) of the obtained cured film was measured. Then, the silicon substrate on which the cured film was formed was immersed in dimethyl sulfoxide whose temperature was controlled at 70 ° C. for 20 minutes, and then the film thickness (t1) of the cured film after the immersion was measured to change the film thickness. The rate was calculated from the following formula and used as an index of chemical resistance.
Film thickness change rate = {(t1-T1) / T1} x 100 (%)
When the absolute value of this value is less than 5%, it can be evaluated as good chemical resistance, and when it is 5% or more, it can be evaluated as defective. Further, when the absolute value is less than 2%, the chemical resistance can be evaluated as particularly good.

[Heat-resistant]
After applying each cured film-forming resin material on a silicon substrate using a spinner, it was prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The obtained coating film was irradiated with ultraviolet rays by a mercury lamp so that the integrated irradiation amount was 1,000 J / m ² . Next, this silicon substrate was heated on a hot plate at 200 ° C. for 30 minutes to obtain a cured film. The 5% weight loss temperature of the obtained cured film was measured in air using a measuring device (“TG / DTA220U” manufactured by SII Nanotechnology Co., Ltd.) and used as an index of heat resistance. At this time, if the 5% weight loss temperature is 300 ° C. or higher, the heat resistance can be evaluated as good, and if it is less than 300 ° C., the heat resistance can be evaluated as poor. Further, when the 5% weight loss temperature is 320 ° C. or higher, the heat resistance is more good, and when the temperature is 340 ° C. or higher, the heat resistance is particularly good.

[Transmittance (transparency)]
Each resin material for forming a cured film was applied onto a glass substrate using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The obtained coating film was irradiated with ultraviolet rays by a mercury lamp so that the integrated irradiation amount was 1,000 J / m ² . Next, this glass substrate was heated on a hot plate at 200 ° C. for 30 minutes to obtain a cured film. The transmittance of the obtained cured film was measured using an ultraviolet-visible spectrophotometer (“V-630” manufactured by JASCO Corporation). At this time, a case where the transmittance of light having a wavelength of 400 nm is 95% or more can be evaluated as good (transparency is good), and a case where the transmittance is less than 95% can be evaluated as poor (poor transparency). Further, when the transmittance is 97% or more, the transparency can be evaluated as better, and when the transmittance is 98% or more, the transparency can be evaluated as particularly good.

[Pencil hardness (surface hardness)]
After applying each cured film-forming resin material on a silicon substrate using a spinner, it was prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The obtained coating film was irradiated with ultraviolet rays by a mercury lamp so that the integrated irradiation amount was 1,000 J / m ² . Next, this silicon substrate was heated at 200 ° C. for 30 minutes on a hot plate to obtain a cured film. Then, the pencil hardness of the cured film was measured by the 8.4.1 pencil scratch test of JIS-K-5400 (1990) on the substrate on which the cured film was formed, and this was used as an index of the surface hardness. When the pencil hardness is 3H or more, the surface hardness of the cured film is good (the resin material for forming the cured film has sufficient curability), and when it is 2H or less, it can be evaluated as poor.

[Relative permittivity (low dielectric constant)]
Each resin material for forming a cured film was applied onto a SUS substrate using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a film thickness of 3.0 μm. The coating film was exposed using an exposure machine (“MPA-600FA” manufactured by Canon Inc.) so that the integrated irradiation dose was 1,000 J / m ² . Then, the exposed substrate was heated at 200 ° C. for 30 minutes in a clean oven to form a cured film on the SUS substrate. Next, a Pt / Pd electrode pattern was formed on the cured film by a thin-film deposition method to prepare a sample for measuring the dielectric constant. For a substrate having this electrode pattern, an electrode ("HP16451B" by Yokogawa Hewlett-Packard) and a precision LCR meter ("HP4284A" by Yokogawa Hewlett-Packard) were used to determine the relative permittivity by the CV method at a frequency of 10 kHz. The measurement was performed. At this time, a case where the relative permittivity is 3.9 or less can be evaluated as good, and a case where the relative permittivity exceeds 3.9 can be evaluated as defective. Further, the case where the relative permittivity is 3.4 or less can be evaluated as better, and the case where the relative permittivity is 3.3 or less can be evaluated as particularly good.

As can be seen from the evaluation results in Tables 2 and 3, both characteristics were good in the examples. In particular, as shown in Table 2, the cured film-forming resin materials (1) of Examples 1 to 3 have higher heat resistance and permeability than the cured film-forming resin materials (1) of Comparative Examples 1 to 4. It can be seen that both the rate (transparency) and the pencil hardness (surface hardness) are excellent. Further, as shown in Table 3, the cured film-forming resin materials (2) of Examples 4 to 50 have higher chemical resistance and heat resistance than the cured film-forming resin materials (2) of Comparative Examples 5 to 8. It can be seen that the properties, transmittance (transparency) and relative permittivity (low dielectric constant) are all excellent.

In particular, as shown in Table 3, Examples 11, 12, 20 to 25 and 35 are all excellent in heat resistance, transparency, surface hardness and low dielectric property. In these, the [A] polymer contains a structural unit in which the structural unit (I) is represented by the above formula (3-1) or (3-2) and a structural unit having a carboxy group, and the structural unit ( II) is a structural unit represented by the above formula (5-2), and structural unit (III) is a structural unit having an oxylanyl group or a methylol group, and the above formulas (3-1) and (3-2). It is presumed that R ⁴ and R ^{5 in the} group are perfluoroalkyl groups, and the content ratio of the structural unit having a carboxy group is relatively high.

The present invention is for forming a cured film having excellent surface hardness, capable of forming a cured film that can sufficiently satisfy general properties such as chemical resistance, heat resistance, transparency, and low dielectric property, and having excellent storage stability. A resin material can be provided. Therefore, the resin material for forming the cured film, the cured film formed from the resin material for forming the cured film, the semiconductor element and the display element, and the method for forming the cured film are used in the manufacturing process of electronic devices such as flexible displays. It can be preferably used.

Claims (9)

A structural unit having an acidic group, a structural unit having a crosslinkable group, and at least one group selected from a group represented by the following formula (1-1) and a group represented by the following formula (1-2). co-polymer containing a structural unit having,
Antioxidant,
It contains a polymerizable compound having an ethylenically unsaturated bond and a radiation-sensitive polymerization initiator.
A resin material for forming a cured film, wherein the crosslinkable group is an oxylanyl group, an oxetanyl group, a methylol group, or a combination thereof.

(In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independent hydrogen atoms and halogens, respectively. It is an atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a phenyl group. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms or 1 carbon atom. If .A ¹ is more a 6 alkyl groups, each independently plurality of ^{a 1} may satisfy the above definition .n1 is an integer of 0 to 4. * indicates a binding site.
In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site. ) Structural unit having an acidic group, and a co-polymer comprising a structural unit having at least one group selected from the groups represented by groups and the following formula represented by the following formula (1-1) (1-2) ,
Antioxidant,
It contains a polymerizable compound having an ethylenically unsaturated bond and a radiation-sensitive polymerization initiator.
A resin material for forming a cured film, wherein the acidic group is a group represented by the following formula (2).

(In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independent hydrogen atoms and halogens, respectively. It is an atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a phenyl group. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms or 1 carbon atom. If .A ¹ is more a 6 alkyl groups, each independently plurality of ^{a 1} may satisfy the above definition .n1 is an integer of 0 to 4. * indicates a binding site.
In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site. )

(In the above formula (2), R ⁴ is a fluorine atom or a fluorinated alkyl group having 1 to 4 carbon atoms. R ⁵ is a hydrogen atom, a fluorine atom, an alkyl group having 1 to 4 carbon atoms or 1 carbon atom. ~ 4 alkyl fluorinated groups.) Structural unit having an acidic group, and a co-polymer comprising a structural unit having at least one group selected from the groups represented by groups and the following formula represented by the following formula (1-1) (1-2) ,
Antioxidant,
It contains a polymerizable compound having an ethylenically unsaturated bond and a radiation-sensitive polymerization initiator.
The radiation-sensitive polymerization initiator is an oxime ester compound.
A resin material for forming a cured film in which the content of the oxime ester compound is 0.1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the polymer.

(In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independent hydrogen atoms and halogens, respectively. It is an atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a phenyl group. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms or 1 carbon atom. If .A ¹ is more a 6 alkyl groups, each independently plurality of ^{a 1} may satisfy the above definition .n1 is an integer of 0 to 4. * indicates a binding site.
In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site. ) A structural unit having an acidic group, a structural unit having a crosslinkable group, and at least one group selected from a group represented by the following formula (1-1) and a group represented by the following formula (1-2). co-polymer containing a structural unit having,
It contains a polymerizable compound having an ethylenically unsaturated bond and a radiation-sensitive polymerization initiator.
A resin material for forming a cured film, wherein the crosslinkable group is an oxylanyl group, an oxetanyl group, a methylol group, or a combination thereof.

(In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independent hydrogen atoms and halogens, respectively. It is an atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a phenyl group. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms or 1 carbon atom. If .A ¹ is more a 6 alkyl groups, each independently plurality of ^{a 1} may satisfy the above definition .n1 is an integer of 0 to 4. * indicates a binding site.
In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site. ) Structural unit having an acidic group, and a co-polymer comprising a structural unit having at least one group selected from the groups represented by groups and the following formula represented by the following formula (1-1) (1-2) ,
It contains a polymerizable compound having an ethylenically unsaturated bond and a radiation-sensitive polymerization initiator.
A resin material for forming a cured film, wherein the acidic group is a group represented by the following formula (2).

(In the above formula (1-1), R ¹ is a hydrogen atom, a halogen atom, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are independent hydrogen atoms and halogens, respectively. It is an atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a phenyl group. A ¹ is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms or 1 carbon atom. If .A ¹ is more a 6 alkyl groups, each independently plurality of ^{a 1} may satisfy the above definition .n1 is an integer of 0 to 4. * indicates a binding site.
In the above formula (1-2), R ¹ , R ² and R ³ are synonymous with the above formula (1-1). A ² is a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. If A ² is plural, each independently plurality of A ² satisfy the above definition. n2 is an integer from 0 to 6. * Indicates the binding site. )

(In the above formula (2), R ⁴ is a fluorine atom or a fluorinated alkyl group having 1 to 4 carbon atoms. R ⁵ is a hydrogen atom, a fluorine atom, an alkyl group having 1 to 4 carbon atoms or 1 carbon atom. ~ 4 alkyl fluorinated groups.) A step of forming a coating film on a substrate by using the resin material for forming a cured film according to any one of claims 1 to 5 .
The process of irradiating a part of the coating film with radiation,
A method for forming a cured film, comprising a step of developing the coating film irradiated with radiation and a step of heating the developed coating film. A cured film formed from the resin material for forming a cured film according to any one of claims 1 to 5 . A semiconductor device including the cured film according to claim 7 . A display element including the semiconductor element according to claim 8 .