JP5471851B2 - Radiation-sensitive resin composition, cured film, method for forming cured film, and display element - Google Patents

Description

  The present invention relates to a radiation-sensitive resin composition suitable as a material for forming a cured film such as an interlayer insulating film, a protective film, or a spacer, a cured film formed from the composition, a method for forming the cured film, and a display element.

  An electronic component such as a thin film transistor (TFT) type liquid crystal display element is generally provided with an interlayer insulating film for insulating between wirings arranged in layers. For example, a TFT-type liquid crystal display element is manufactured through a process of forming a transparent electrode film on an interlayer insulating film and further forming a liquid crystal alignment film thereon. Since such an interlayer insulating film is exposed to a high temperature condition or a resist stripping solution used for electrode pattern formation in the transparent electrode film forming step, sufficient heat resistance and chemical resistance to these are required. In addition, the radiation-sensitive resin composition used for forming such a cured film is required to have a shortened irradiation time (that is, high radiation sensitivity) and good storage stability.

  In recent years, lightweight and small flexible displays using TFT technology have become widespread. As a substrate for a flexible display, a plastic substrate such as polycarbonate has been studied. The plastic substrate is stretched and contracted by heating, and as a result, there is a disadvantage that the display function is hindered. For this reason, lowering the temperature in the heating process of flexible display manufacturing has been studied. For example, Japanese Unexamined Patent Application Publication No. 2009-4394 discloses a coating liquid for a gate insulating film for a flexible display containing a polyimide precursor that can be cured even by low-temperature baking. However, since this coating solution does not have the ability to form a pattern by exposure and development, it is impossible to form a fine pattern. In addition, the cured film obtained is not satisfactory in heat resistance, chemical resistance, transmittance, flatness, voltage holding ratio, linear thermal expansion resistance, etc. due to insufficient progress of the curing reaction. It's not a good level.

  Therefore, it is conceivable to proceed with the crosslinking reaction by adding an amine compound used as a curing agent for epoxy-based materials even at low temperatures. However, the addition of a general amine compound may cause a reaction with time with an epoxy group present in the composition, resulting in a decrease in storage stability.

  From such a situation, the radiation-sensitive resin composition for forming a cured film having both storage stability and low-temperature firing and sufficient radiation sensitivity, and the required properties as a cured film, heat resistance, chemical resistance, Development of a cured film having excellent transmittance, flatness, voltage holding ratio, linear thermal expansion resistance, and the like is desired.

JP 2009-4394 A

  The present invention has been made based on the circumstances as described above, and its purpose is to achieve both a storage stability and a low-temperature firing, and a radiation-sensitive resin composition for forming a cured film having sufficient radiation sensitivity, And a cured film excellent in heat resistance, chemical resistance, transmittance, flatness, voltage holding ratio, linear thermal expansion property, etc., which are required characteristics as a cured film, a method for forming the cured film, and a display element. It is.

The invention made to solve the above problems is
[A] a polymer having an epoxy group (hereinafter sometimes referred to as “[A] polymer”),
[B] a polymerizable compound having an ethylenically unsaturated bond (hereinafter sometimes referred to as “[B] polymerizable compound”),
[C] Radiation sensitive polymerization initiator (hereinafter sometimes referred to as “[C] polymerization initiator”), and [D] Compounds represented by the following formulas (1) to (3) (hereinafter referred to as “[ D) a radiation-sensitive resin composition comprising at least one compound selected from “sometimes referred to as a compound”).

（式（１）中、Ｒ^１、Ｒ^２は、それぞれ独立に、水素原子、炭素数１〜１２のアルキル基、シクロヘキシル基、フェニル基、ナフチル基、ビニル基、２−ピリジル基または、炭素数１〜６のアルキル基、ハロゲン、ヒドロキシル基、カルボキシル基、アセチル基で置換されても良い炭素数１〜１２のアルキル基、フェニル基、ナフチル基を示す。
式（２）中、Ｒ^３、Ｒ^４は、それぞれ独立に、水素原子、炭素数１〜１２のアルキル基、シクロヘキシル基であり、Ａはメチレン基、炭素数２〜１２のアルキレン基、フェニレン基、ナフチレン基、ビニレン基、または炭素数１〜６のアルキル基、ハロゲンで置換されてもよいメチレン基、炭素数２〜１２のアルキレン基、フェニレン基、ナフチレン基を示す。
式（３）中、Ｒ^５、Ｒ^６は、それぞれ独立に、水素原子、炭素数１〜１２のアルキル基、シクロヘキシル基であり、Ａはメチレン基、炭素数２〜１２のアルキレン基、フェニレン基、ナフチレン基、ビニレン基、または炭素数１〜６のアルキル基、ハロゲンで置換されてもよいメチレン基、炭素数２〜１２のアルキレン基、フェニレン基、ナフチレン基を示す。）

(In the formula ^{(1), R 1, R} 2 are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cyclohexyl group, a phenyl group, a naphthyl group, a vinyl group, a 2-pyridyl group or a carbon atoms An alkyl group having 1 to 6 carbon atoms, a phenyl group or a naphthyl group which may be substituted with an alkyl group of 1 to 6, a halogen, a hydroxyl group, a carboxyl group or an acetyl group.
In formula (2), R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyclohexyl group, and A is a methylene group, an alkylene group having 2 to 12 carbon atoms, or a phenylene group. , A naphthylene group, a vinylene group, or an alkyl group having 1 to 6 carbon atoms, a methylene group that may be substituted with a halogen, an alkylene group having 2 to 12 carbon atoms, a phenylene group, or a naphthylene group.
In formula (3), R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyclohexyl group, and A is a methylene group, an alkylene group having 2 to 12 carbon atoms, or a phenylene group. , A naphthylene group, a vinylene group, or an alkyl group having 1 to 6 carbon atoms, a methylene group that may be substituted with a halogen, an alkylene group having 2 to 12 carbon atoms, a phenylene group, or a naphthylene group. )

  In the composition, the polymer having an [A] epoxy group is a copolymer further having a carboxyl group (hereinafter sometimes referred to as “[A] copolymer”). It is a radiation sensitive resin composition.

[A] a polymer as an alkali-soluble resin, [B] a polymerizable compound, [C] a polymerization initiator, and a [D] compound are contained. The composition, which is a photosensitive material, can easily form a fine and fine pattern by exposure and development utilizing radiation sensitivity, and has sufficient radiation sensitivity. Moreover, the said composition contains the [D] compound which has an amide group represented by said formula (1)-(3) in a molecule | numerator. When the composition contains the [D] compound, both storage stability and low-temperature firing can be achieved. The compound [D] is a compound having a primary or secondary amide group, and such a compound has a low nucleophilicity with respect to an epoxy group as compared with a compound having a primary or secondary amino group, Under room temperature, the epoxy group curing reaction hardly proceeds. Therefore, the composition has excellent storage stability. On the other hand, when the composition is heated to a predetermined temperature or higher, the compound [D] accelerates the curing reaction of the epoxy group-containing resin and functions as an epoxy group curing accelerator.

  The [C] polymerization initiator is preferably at least one selected from the group consisting of an acetophenone compound and an O-acyloxime compound. [C] By using the specific compound as a polymerization initiator, the required characteristics as a cured film such as heat resistance can be further improved even in the case of a low exposure amount.

The method for forming the cured film of the present invention is as follows.
(1) The process of forming the coating film of the said composition on a board | substrate (2) The process of irradiating at least one part of the coating film formed at the process (1),
(3) a step of developing the coating film irradiated with radiation in the step (2), and (4) a step of baking the coating film developed in the step (3).

  By the forming method of the present invention using the composition, a cured film satisfying in a well-balanced required characteristics such as heat resistance, chemical resistance, transmittance, flatness, voltage holding ratio, and linear thermal expansion resistance can be formed.

  It is preferable that the calcination temperature of the said process (4) is 200 degrees C or less. Since the composition contains the [D] compound as described above, such low-temperature firing is realized, storage stability is compatible, and sufficient radiation sensitivity is obtained. Therefore, the composition is suitably used as a material for forming a cured film such as an interlayer insulating film, a protective film, and a spacer used in a flexible display or the like where low temperature baking is desired.

  A cured film as an interlayer insulating film, protective film or spacer formed from the composition is also suitably included in the present invention. Moreover, a display element provided with this cured film is also suitably included in the present invention.

  Note that “baking” in the present specification means heating until a surface hardness required for a cured film such as an interlayer insulating film, a protective film, and a spacer is obtained. The “radiation” of the “radiation sensitive resin composition” is a concept including visible light, ultraviolet light, far ultraviolet light, X-rays, charged particle beams and the like.

  As described above, the radiation-sensitive resin composition of the present invention can easily form a fine and elaborate pattern, achieves both storage stability and low-temperature firing, and has sufficient radiation sensitivity. Moreover, the cured film formed from the composition is excellent in the required properties such as heat resistance, chemical resistance, transmittance, flatness, voltage holding ratio, and linear thermal expansion resistance. Therefore, the composition is suitably used as a material for forming a cured film such as an interlayer insulating film, a protective film, or a spacer used in a flexible display or the like where low-temperature firing is desired.

  Hereinafter, embodiments of the present invention will be described in detail.

<Radiation sensitive resin composition>
The radiation sensitive resin composition of the present invention contains a [A] polymer, a [B] polymerizable compound, a [C] polymerization initiator, and a [D] compound, and may further contain optional components. The composition, which is a photosensitive material, can easily form a fine and fine pattern by exposure and development utilizing radiation sensitivity, and has sufficient radiation sensitivity. Moreover, the said composition can make storage stability and low-temperature baking compatible by containing a [D] compound. Hereinafter, each component will be described in detail.

<[A] Compound having an epoxy group>
The compound having an [A] epoxy group in the present invention (hereinafter also referred to as [A] polymer) is a polymer having two or more glycidyl groups or 3,4-epoxycyclohexyl groups in the molecule.
Specific examples of the polymer having an epoxy group include polyglycidyl ethers of polyhydric alcohols such as polyethylene glycol diglycidyl ether and polypropylene glycol diglycidyl ether; 1 per aliphatic polyhydric alcohol such as ethylene glycol, propylene glycol and glycerin. Aliphatic polyglycidyl ethers of polyether polyols obtained by adding seeds or two or more alkylene oxides; phenol novolac epoxy resins such as bisphenol A novolac epoxy resins; cresol novolac epoxy resins; polyphenol epoxy resins Cycloaliphatic epoxy resin; diglycidyl esters of aliphatic long-chain dibasic acids; glycidyl esters of higher fatty acids; epoxidized soybean oil, epoxidized linseed oil, etc. It can gel. Of these compounds having two or more epoxy groups in the molecule, phenol novolac type epoxy resins and polyphenol type epoxy resins are preferred.

In the present invention, the polymer having an [A] epoxy group is preferably a copolymer having a carboxyl group (hereinafter sometimes referred to as “[A] copolymer”).
[A] The copolymer has (a1) a carboxyl group-containing structural unit and (a2) an epoxy group-containing structural unit. [A] As a method for obtaining a copolymer, for example, (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride (hereinafter referred to as an unsaturated carboxylic acid anhydride) that gives a carboxyl group-containing structural unit (the carboxyl group includes an acid anhydride group). (Sometimes referred to as “compound (i)”) and (a2) a radical polymerizable compound having an epoxy group that gives an epoxy group-containing structural unit (hereinafter sometimes referred to as “compound (ii)”) in a solvent. It can be obtained by copolymerization using a polymerization initiator. Further, as necessary, as (a3), a radically polymerizable compound such as (meth) acrylic acid alkyl ester (hereinafter sometimes referred to as “compound (iii)”) is converted to the above compound (i) or compound (ii). It is good also as making it contain and copolymerize and making it a [A] copolymer.

Examples of the compound (i) include acrylic acid, methacrylic acid, crotonic acid, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxyethyl hexahydro. Monocarboxylic acids such as phthalic acid;
Dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid;
Examples thereof include dicarboxylic acid anhydrides such as maleic anhydride.

  Of these, acrylic acid, methacrylic acid, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, maleic anhydride, from the viewpoint of copolymerization reactivity and solubility of the resulting copolymer in an alkaline developer Acid is preferred.

  [A] In the copolymer, compound (i) can be used alone or in admixture of two or more. [A] In the copolymer, the content of the compound (i) is preferably 1% by mass to 40% by mass, more preferably 7% by mass to 30% by mass, and particularly preferably 8% by mass to 25% by mass. By setting the content of the compound (i) to 1% by mass to 40% by mass, a radiation sensitive resin composition optimized with higher levels of characteristics such as radiation sensitivity, developability and storage stability is obtained. It is done.

Examples of the compound (ii) include radical polymerizable compounds having an epoxy group (oxiranyl group, oxetanyl group) and the like. Examples of the radical polymerizable compound having an oxiranyl group include glycidyl acrylate, 2-methylglycidyl acrylate, 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate, 3,4-epoxycyclohexyl acrylate, Acrylic acid epoxy alkyl esters such as acrylic acid-3,4-epoxycyclohexylmethyl;
Such as glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate, and 3,4-epoxycyclohexylmethyl methacrylate Methacrylic acid epoxy alkyl ester;
α-alkylacrylic acid epoxy alkyl esters such as α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylate glycidyl, α-ethyl acrylate 6,7-epoxyheptyl;
Examples thereof include glycidyl ethers such as o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether.

  Examples of the radical polymerizable compound having an oxetanyl group include 3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, 3- (methacryloyloxymethyl) -2-methyloxetane, 3- ( Methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -3-ethyloxetane, 2-ethyl-3- (methacryloyloxyethyl) oxetane, 3- (acryloyloxymethyl) oxetane, 3- (acryloyloxymethyl) -3 -Ethyloxetane, 3- (acryloyloxymethyl) -2-methyloxetane, 3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -3-ethyloxetane, 2-ethyl-3- (acryloyl) Oxyethyl) oxetane, 2- (methacryloyloxymethyl) oxetane, 2-methyl-2- (methacryloyloxymethyl) oxetane, 3-methyl-2- (methacryloyloxymethyl) oxetane, 4-methyl-2- (methacryloyloxymethyl) Oxetane, 2- (2- (2-methyloxetanyl)) ethyl methacrylate, 2- (2- (3-methyloxetanyl)) ethyl methacrylate, 2- (methacryloyloxyethyl) -2-methyloxetane, 2- (methacryloyloxy) Ethyl) -4-methyloxetane, 2- (acryloyloxymethyl) oxetane, 2-methyl-2- (acryloyloxymethyl) oxetane, 3-methyl-2- (acryloyloxymethyl) oxetane, 4-methyl-2- ( Acrylo Ruoxymethyl) oxetane, 2- (2- (2-methyloxetanyl)) ethyl methacrylate, 2- (2- (3-methyloxetanyl)) ethyl methacrylate, 2- (acryloyloxyethyl) -2-methyloxetane, 2- ( And methacrylic acid esters such as acryloyloxyethyl) -4-methyloxetane.

  Among these, glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 3- (acryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl)- 3-ethyloxetane and 2- (methacryloyloxymethyl) oxetane have high adhesion to substrates of cured films such as interlayer insulating films, protective films, and spacers obtained, have high heat resistance, and reliability in display elements It is preferable from the point which raises.

  [A] In the copolymer, compound (ii) can be used alone or in admixture of two or more. [A] In the copolymer, the content of the compound (ii) is preferably 1% by mass to 70% by mass, and more preferably 15% by mass to 65% by mass. Radiation-sensitive resin composition that is easy to control the molecular weight of the copolymer and is optimized at a higher level of developability, sensitivity, etc. by setting the content of compound (ii) to 1 mass% to 70 mass% A thing is obtained.

  As compound (iii), (meth) acrylic acid alkyl ester, (meth) acrylic acid alicyclic ester, unsaturated hetero five-membered ring containing oxygen atom and six-membered ring (meth) acrylic ester, and hydroxyl group ( Examples include (meth) acrylic acid ester, (meth) acrylic acid aryl ester, unsaturated dicarboxylic acid diester, maleimide compound, hydroxyalkyl ester of (meth) acrylic acid, styrene, α-methylstyrene, and 1,3-butadiene.

  Examples of the (meth) acrylic acid alkyl ester include methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, sec-butyl acrylate, t- Examples include butyl acrylate.

  Examples of (meth) acrylic acid alicyclic alkyl esters include cyclopentyl methacrylate, cyclohexyl methacrylate, methacrylic acid-2-methylcyclohexyl, methacrylic acid tricyclodicyclopentani, methacrylic acid-2-dicyclopentanyloxyethyl, Examples include isobornyl methacrylate, cyclopentyl acrylate, cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclodicyclopentani acrylate, 2-dicyclopentanyloxyethyl acrylate, isobornyl acrylate, and the like.

Examples of unsaturated heterocyclic 5-membered and 6-membered methacrylic acid esters containing an oxygen atom include tetrahydrofurfuryl (meth) acrylate, 2-methacryloyloxy-propionic acid tetrahydrofurfuryl ester, 3- (meth) acryloyloxytetrahydrofuran- Unsaturated compounds containing a tetrahydrofuran skeleton such as 2-one;
2-methyl-5- (3-furyl) -1-penten-3-one, furfuryl (meth) acrylate, 1-furan-2-butyl-3-en-2-one, 1-furan-2-butyl- 3-methoxy-3-en-2-one, 6- (2-furyl) -2-methyl-1-hexen-3-one, 6-furan-2-yl-hex-1-en-3-one, Unsaturated compounds containing a furan skeleton such as acrylic acid-2-furan-2-yl-1-methyl-ethyl ester, 6- (2-furyl) -6-methyl-1-hepten-3-one;
(Tetrahydropyran-2-yl) methyl methacrylate, 2,6-dimethyl-8- (tetrahydropyran-2-yloxy) -oct-1-en-3-one, 2-methacrylic acid tetrahydropyran-2-yl ester, Unsaturated compounds containing a tetrahydropyran skeleton such as 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one;
4- (1,4-dioxa-5-oxo-6-heptenyl) -6-methyl-2-pyran, 4- (1,5-dioxa-6-oxo-7-octenyl) -6-methyl-2- Examples thereof include unsaturated compounds containing a pyran skeleton such as pyran.

  Examples of (meth) acrylic acid ester having a hydroxyl group include (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, (meth) acrylic acid-3-hydroxypropyl, and (meth) acrylic acid. -2,3-dihydroxypropyl and the like.

  Examples of the (meth) acrylic acid aryl ester include phenyl (meth) acrylate and benzyl (meth) acrylate.

  Examples of the unsaturated dicarboxylic acid diester include diethyl maleate, diethyl fumarate, diethyl itaconate and the like.

  Examples of maleimide compounds include N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N- (4-hydroxyphenyl) maleimide, N- (4-hydroxybenzyl) maleimide, N-succinimidyl-3-maleimidobenzoate, N-succinimidyl-4-maleimidobutyrate, N-succinimidyl-6-maleimidocaproate, N-succinimidyl-3-maleimidopropionate, N- (9-acridinyl) maleimide and the like.

  [A] In the copolymer, the content of the compound (iii) is preferably 10% by mass to 70% by mass, and more preferably 15% by mass to 65% by mass. By controlling the copolymerization ratio of the compound (iii) to 10% by mass to 70% by mass, it becomes easy to control the molecular weight of the copolymer, and the development, sensitivity, adhesion, etc. are optimized at a higher level. A radiation resin composition is obtained.

<[A] Copolymer Synthesis Method>
The copolymer [A] can be synthesized, for example, by polymerizing the compound (i), the compound (ii) and, if necessary, the compound (iii) in a solvent using a radical polymerization initiator.

  [A] Solvents used in the polymerization reaction for producing the copolymer include, for example, alcohols, ethers, glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol alkyl ethers, propylene glycol monoalkyl ethers, propylene glycol monoalkyls. Examples include ether acetate, propylene glycol monoalkyl ether propionate, aromatic hydrocarbons, ketones, and other esters.

  Examples of alcohols include methanol, ethanol, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol and the like.

  Examples of ethers include cyclic ether, glycol ether, ethylene glycol alkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether, propylene glycol monoalkyl ether acetate, propylene glycol monoalkyl ether propionate and the like.

  Examples of the cyclic ether include tetrahydrofuran and the like.

  Examples of the glycol ether include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether.

  Examples of the ethylene glycol alkyl ether acetate include methyl cellosolve acetate, ethyl cellosolve acetate, ethylene glycol monobutyl ether acetate, and ethylene glycol monoethyl ether acetate.

  Examples of the diethylene glycol alkyl ether include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol ethyl methyl ether.

  Examples of the propylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether and the like.

  Examples of the propylene glycol monoalkyl ether acetate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate and the like.

  Examples of the propylene glycol monoalkyl ether propionate include propylene monoglycol methyl ether propionate, propylene glycol monoethyl ether propionate, propylene glycol monopropyl ether propionate, propylene glycol monobutyl ether propionate and the like. .

  Examples of aromatic hydrocarbons include toluene and xylene.

  Examples of ketones include methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, and the like.

  Examples of other esters include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, hydroxy Methyl acetate, ethyl hydroxyacetate, butyl hydroxyacetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl 3-hydroxypropionate Methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, propyl ethoxyacetate, butyl ethoxyacetate, Methyl ropoxyacetate, ethyl propoxyacetate, propylpropoxyacetate, butyl propoxyacetate, methyl butoxyacetate, ethyl butoxyacetate, propylbutoxyacetate, butylbutoxyacetate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, 2-methoxypropionate Propyl acid, butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, 2-butoxypropionic acid Ethyl, propyl 2-butoxypropionate, butyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, 3-methyl Butyl xylpropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, propyl 3-ethoxypropionate, butyl 3-ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, 3-propoxy Examples include propyl propionate, butyl 3-propoxypropionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate, and butyl 3-butoxypropionate.

  Examples of the radical polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), and 2,2′-azobis- (4-methoxy). -2,4-dimethylvaleronitrile), 4,4'-azobis (4-cyanovaleric acid), dimethyl-2,2'-azobis (2-methylpropionate), 2,2'-azobis (4-methoxy) -2,4-dimethylvaleronitrile) and the like.

  Of these, 2,2'-azobisisobutyronitrile and 2,2'-azobis (2,4-dimethylvaleronitrile) are preferable.

  A radical polymerization initiator can be used individually or in mixture of 2 or more types. As a usage-amount of a radical polymerization initiator, 0.1 mass%-50 mass% are preferable normally with respect to a total of 100 mass% of a compound (i), a compound (ii), and a compound (iii). The mass% to 20 mass% is more preferable.

In the polymerization reaction, a molecular weight modifier 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, thioglycolic acid;
Xanthogens such as dimethylxanthogen sulfide and diisopropylxanthogen disulfide;
Examples include terpinolene and α-methylstyrene dimer.

  As a usage-amount of a molecular weight modifier, it is 0.1 mass%-50 mass% normally, and 0.2 mass%-16 with respect to the total 100 mass% of a compound (i), a compound (ii), and a compound (iii). % By mass is preferable, and 0.4% by mass to 8% by mass is more preferable. As polymerization temperature, 0 degreeC-150 degreeC and 50 degreeC-120 degreeC are preferable normally. The polymerization time is usually preferably 10 minutes to 20 hours and 30 minutes to 6 hours.

The polystyrene-reduced weight average molecular weight of [A] a copolymer (Mw), preferably from ^{2.0 × 10 3 ~1.0 × 10 5} , more preferably 5.0 × ¹⁰ 3 ~5.0 × ^{10 4} . [A] By setting Mw of the copolymer to 2.0 × 10 ³ or more, a sufficient development margin of the radiation-sensitive resin composition is obtained, and the remaining film ratio of the coating film to be formed (the patterned thin film is appropriate) The ratio of the remaining ratio of the insulating film can be prevented from decreasing, and the pattern shape and heat resistance of the obtained insulating film can be kept good. On the other hand, when the Mw of the [A] copolymer is 1.0 × 10 ⁵ or less, high radiation sensitivity is maintained and a good pattern shape can be obtained. [A] The molecular weight distribution (Mw / Mn) of the copolymer is preferably 5.0 or less, and more preferably 3.0 or less. [A] By setting Mw / Mn of the copolymer to 5.0 or less, the pattern shape of the obtained insulating film can be kept good. Moreover, since the radiation sensitive resin composition containing the [A] copolymer having Mw and Mw / Mn in the preferable ranges as described above has high developability, there is no development residue in the development process. A predetermined pattern shape can be easily formed.

<[B] Polymerizable compound>
[B] The polymerizable compound is a polymerizable compound having an ethylenically unsaturated bond. Examples of the [B] polymerizable compound contained in the composition include ω-carboxypolycaprolactone mono (meth) acrylate, ethylene glycol (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9 -Nonanediol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, bisphenoxyethanol full orange (meth) acrylate, dimethylol tricyclodecanedi ( (Meth) acrylate, 2-hydroxy-3- (meth) acryloyloxypropyl methacrylate, 2- (2′-vinyloxyethoxy) ethyl (meth) acrylate, trimethylolpropane tri (meth) acryl , Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tri (2- (meth) acryloyloxyethyl) phos In addition to fete, ethylene oxide-modified dipentaerythritol hexaacrylate, succinic acid-modified pentaerythritol triacrylate, etc., a compound having a linear alkylene group and an alicyclic structure and having two or more isocyanate groups, Examples thereof include urethane (meth) acrylate compounds obtained by reacting with a compound having one or more hydroxyl groups and 3 to 5 (meth) acryloyloxy groups.

As a commercial item of the above-mentioned [B] polymerizable compound, for example, Aronix M-400, M-402, M-405, M-450, M-1310, M-1600, M-1960, M-7100, M-8030, M-8060, M-8100, 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 (Osaka Organic Chemical Co., Ltd.)
As a urethane acrylate compound, New Frontier R-1150 (Daiichi Kogyo Seiyaku Co., Ltd.);
KAYARAD DPHA-40H, UX-5000 (Nippon Kayaku Co., Ltd.);
UN-9000H (Negami Kogyo),
Aronix M-5300, M-5600, M-5700, M-210, M-220, M-240, M-270, M-6200, M-305, M-309, M M-310, M-315 (above, Toagosei Co., Ltd.);
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-9000PEP, UN-9200A, UN-7600, UN-333, UN-1003, UN-1255, UN-6060PTM, UN-6060P (Negami Industrial Co., Ltd.);
SH-500B biscoat 260, 312 and 335HP (above, Osaka Organic Chemical Industry Co., Ltd.).

  [B] A polymeric compound can be used individually or in mixture of 2 or more types. As a content rate of the [B] polymeric compound in the said composition, 20 mass parts-200 mass parts are preferable with respect to 100 mass parts of [A] polymer or [A] copolymer, and 40 mass parts -160. Part by mass is more preferable. [B] By setting the content ratio of the polymerizable compound in the above range, the composition has a cured film such as an interlayer insulating film, a protective film and a spacer having excellent adhesion and sufficient hardness even at a low exposure amount. can get.

<[C] Polymerization initiator>
The [C] polymerization initiator contained in the composition is a component that generates an active species capable of initiating polymerization of the [B] polymerizable compound in response to radiation. [C] The polymerization initiator preferably contains at least one selected from the group consisting of an O-acyloxime compound and an acetophenone compound.

  Examples of the O-acyloxime compound include 1,2-octanedione-1- [4- (phenylthio) -2- (O-benzoyloxime)], ethanone-1- [9-ethyl-6- (2-methyl). Benzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime), 1- [9-ethyl-6-benzoyl-9. H. -Carbazol-3-yl] -octane-1-one oxime-O-acetate, 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-benzoate, 1- [9-n-butyl-6- (2-ethylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-benzoate, ethanone-1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylbenzoyl) -9. H. -Carbazol-3-yl] -1- (O-acetyloxime), ethanone-1- [9-ethyl-6- (2-methyl-4-tetrahydropyranylbenzoyl) -9. H. -Carbazol-3-yl] -1- (O-acetyloxime), ethanone-1- [9-ethyl-6- (2-methyl-5-tetrahydrofuranylbenzoyl) -9. H. -Carbazole-3-yl] -1- (O-acetyloxime), ethanone-1- [9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl } -9. H. -Carbazol-3-yl] -1- (O-acetyloxime) and the like.

  Of these, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H -Carbazol-3-yl] -1- (O-acetyloxime), ethanone-1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylmethoxybenzoyl) -9. H. -Carbazol-3-yl] -1- (O-acetyloxime) or ethanone-1- [9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl } -9. H. -Carbazol-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) -butan-1-one, 2-dimethylamino-2- (4-methylbenzyl) -1- (4 -Morpholin-4-yl-phenyl) -butan-1-one, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, and the like.

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

  Of these, α-aminoketone compounds are preferred, and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-dimethylamino-2- (4-methylbenzyl) -1 -(4-Morpholin-4-yl-phenyl) -butan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one are more preferred.

[C] The polymerization initiators can be used alone or in admixture of two or more. [C] By using the specific compound as a polymerization initiator, the required characteristics as a cured film such as heat resistance can be further improved even in the case of a low exposure amount.
As a content rate of the [C] polymerization initiator in the said composition, 1 mass part-40 mass parts are preferable with respect to 100 mass parts of [A] polymer or [A] copolymer, and 5 mass parts-30. Part by mass is more preferable. [C] By setting the content ratio of the polymerization initiator to 1 part by mass to 40 parts by mass, the composition can be used for an interlayer insulating film, a protective film, a spacer, and the like having high hardness and adhesion even in the case of a low exposure amount. A cured film can be formed.

<[D] Compounds represented by general formulas (1) to (3)>
The composition can achieve both storage stability and low-temperature firing by containing a compound having an amide group represented by the above formulas (1) to (3) (hereinafter also referred to as [D] compound).

  The compound represented by the above formula (1) is a compound having one amide bond in the molecule. Specific examples thereof include, for example, acetamide, N-methylacetamide, N-ethylacetamide, Nn-propylacetamide, N-isopropylacetamide, Nn-butylacetamide, N-isobutylacetamide, Nt-butylacetamide. N-hexylacetamide, Nn-octylacetamide, Nn-dodecylacetamide, propionylamide, butyrylamide, valerylamide, isovalerylamide, octanoylamide, acetanilide, acetoacetanilide, o-acetamide benzoic acid, m -Acetamide benzoic acid, p-acetamidobenzoic acid, o-acetamidophenol, m-acetamidophenol, p-acetamidophenol, acetamidonaphthalene, phthalamic acid, acrylic De, benzamide, naphthamide, nicotinamide, isonicotinamide, and the like.

  Among these, when acetamide, N-methylacetamide, or phthalamic acid is used, the composition is excellent in storage stability at room temperature, and improves the heat resistance, voltage holding ratio, etc. of the resulting cured film. Can do.

The compounds represented by the above formulas (2) and (3) are compounds having two amide bonds in the molecule. Specific examples thereof include, for example, phthalamide, isophthalamide, terephthalamide, malonamide, succinamide, glutaramide, adipineamide, pimelinamide, suberinamide, azelainamide, sebacinamide, maleamide, fumaramide,
N, N'-dimethyl-phthalamide, N, N'-dimethyl-isophthalamide, N, N'-dimethyl-terephthalamide, N, N'-diacetyl-o-phenylenediamine, N, N'-diacetyl-m- Phenylenediamine, N, N′-diacetyl-p-phenylenediamine, N, N′-dipropionyl-o-phenylenediamine, N, N′-dipropionyl-m-phenylenediamine, N, N′-dipropionyl-p -Phenylenediamine, N, N'-diacetyl-ethylenediamine, N, N'-diacetyl-propylenediamine, N, N'-diacetyl-butylenediamine, N, N'-diacetyl-hexamethylenediamine, N, N'-diacetyl -Dodecylmethylenediamine, N, N'-dibenzoyl-ethylenediamine, N, N'-dibenzoyll-propyl Range amine, N, N'-dibenzoyl-butylenediamine, N, N'-dibenzoyl-hexamethylenediamine, N, N'-dibenzoyl-dodecylmethylenediamine, N, N'-dinaphthoyl-ethylenediamine, N, N'-dinaphthoyl -Propylenediamine, N, N'-dinaphthoyl-butylenediamine, N, N'-dinaphthoyl-hexamethylenediamine, N, N'-dinaphthoyl-dodecylmethylenediamine and the like.

  From the viewpoint that both the storage stability of the composition and the acceleration of curing can be achieved at a high level, isophthalamide, adipineamide, N, N′-diacetyl-p-phenylenediamine, and N, N′-diacetyl-hexamethylenediamine are preferable. .

  The compound having an amide group improves the storage stability of the composition at room temperature. Moreover, since it is excellent in the reactivity with an epoxy group, it contributes to the low temperature hardening below 200 degreeC.

  As a content rate of the compound represented by said [D] general formula (1)-(3) in the said composition, it is 0.01 with respect to 100 mass parts of [A] polymer or [A] copolymer. Mass parts to 10 parts by mass are preferable, and 0.05 parts to 5 parts by mass are more preferable. [D] By setting the content ratio of the compound to 0.01 parts by mass to 10 parts by mass, both the storage stability of the composition and the acceleration of curing of the cured film can be achieved at a high level, and the obtained protective film, The voltage holding ratio of the display element having a cured film such as an interlayer insulating film or a spacer can be maintained at a high level.

<Optional component>
In addition to the above [A] polymer or [A] copolymer, [B] polymerizable compound, [C] polymerization initiator, and [D] compound, the composition does not impair the intended effect. As needed, [E] a compound having two or more oxiranyl groups in one molecule, [F] an adhesion assistant, [G] a surfactant, [H] a storage stabilizer, and [I] an improvement in heat resistance. An optional component such as an agent can be contained. Each of these optional components may be used alone or in combination of two or more. Hereinafter, it explains in full detail in order.

[[E] Compound having two or more oxiranyl groups in one molecule]
[E] A compound having two or more oxiranyl groups in one molecule (hereinafter sometimes referred to as “[E] compound”) can be added to further improve the hardness of the resulting cured film. Examples of such an [E] compound include compounds having two or more 3,4-epoxycyclohexyl groups in one molecule and other [E] compounds, provided that [A] polymer or [A] ] Copolymers are excluded.

  Examples of the compound having two or more 3,4-epoxycyclohexyl groups in one molecule include 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, 2- (3,4- Epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 3 , 4-epoxy-6-methylcyclohexyl-3 ′, 4′-epoxy-6′-methylcyclohexanecarboxylate, methylenebis (3,4-epoxycyclohexane), dicyclopentadiene diepoxide, di (3,4) of ethylene glycol -Epoxycyclohexylmethyl) Ether, ethylenebis (3,4-epoxycyclohexane carboxylate), lactone-modified 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexane carboxylate and the like.

Examples of the other [E] compounds include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated bisphenol AD di Diglycidyl ethers of bisphenol compounds such as glycidyl ether, brominated bisphenol A diglycidyl ether, brominated bisphenol F diglycidyl ether, brominated bisphenol S diglycidyl ether;

  The amount of the [E] compound used is preferably 50 parts by mass or less, more preferably 2 parts by mass to 50 parts by mass, and more preferably 5 parts by mass with respect to 100 parts by mass of the [A] polymer or [A] copolymer. Part to 30 parts by mass is particularly preferable. [E] By making the usage-amount of a compound into the said range, the hardness of cured films, such as an interlayer insulation film, a spacer, or a protective film, can further be improved, without impairing developability.

[[F] Adhesion aid]
[F] The adhesion assistant can be used to further improve the adhesion between the obtained interlayer insulating film, spacer, or a cured film such as a protective film and the substrate. As such [F] adhesion assistant, a functional silane coupling agent having a reactive functional group such as a carboxyl group, a methacryloyl group, a vinyl group, an isocyanate group, an oxiranyl group is preferable, for example, trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltri And methoxysilane.

  [F] The amount of the adhesion aid used is preferably 20 parts by mass or less and more preferably 15 parts by mass or less with respect to 100 parts by mass of the [A] polymer or [A] copolymer. [F] When the amount of the adhesion aid used exceeds 20 parts by mass, there is a tendency that a development residue tends to occur.

[[G] Surfactant]
[G] A surfactant can be used to further improve the film-forming property of the composition. [G] Examples of the surfactant include a fluorine-based surfactant, a silicone-based surfactant, and other surfactants. The fluorine-based surfactant is preferably a compound having a fluoroalkyl group and / or a fluoroalkylene group in at least one of the terminal, main chain and side chain, 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, 2,3,3-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, sodium fluoroalkylcarboxylate, diglycerin tetrakis (fluoroalkylpolyoxyethylene ether), fluoroalkylammonium iodide, fluoroalkylbetaine, other fluoroalkylpolyoxy Examples thereof include ethylene ether, perfluoroalkyl polyoxyethanol, perfluoroalkyl alkoxylate, and carboxylic acid fluoroalkyl ester.

  Commercially available fluorosurfactants include, for example, BM-1000, BM-1100 (above, BM CHEMIE), MegaFuck F142D, F172, F173, F183, F178, F191, F191, and F471. F476 (above, Dainippon Ink & Chemicals, Inc.), Florard FC-170C, -171, -430, -431 (above, Sumitomo 3M), Surflon S-112, -113, -131, -141, -145, -382, Surflon SC-101, -102, -103, -104, -105, -106 (above, Asahi Glass), F-top EF301, 303, 352 (above, Shin-Akita Kasei Co., Ltd.), Footent FT-100, -110, -140A, -150, -250, and -25 , The -300, the -310, the -400S, Ftergent FTX-218, the -251 (or, Inc. Neos Co., Ltd.).

  Examples of commercially available silicone surfactants include Torresilicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, SZ-6032, SF-8428, DC-57, DC-190 (above, Toray Dow Corning Silicone), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4442 (above GE Toshiba Silicone), organosiloxane polymer KP341 (Shin-Etsu Chemical Co., Ltd.) and the like.

  Examples of other surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene-n-octylphenyl ether, polyoxyethylene-n- Polyoxyethylene aryl ethers such as nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; (meth) acrylic acid copolymer polyflow No. 57, no. 95 (above, Kyoeisha Chemical Co., Ltd.).

  [G] The amount of the surfactant used is preferably 1.0 part by mass or less and more preferably 0.5 part by mass or less with respect to 100 parts by mass of the [A] polymer or [A] copolymer. [G] When the amount of the surfactant used exceeds 1.0 part by mass, film unevenness tends to occur.

[[H] Storage stabilizer]
Examples of the [H] storage stabilizer include sulfur, quinones, hydroquinones, polyoxy compounds, amines, nitronitroso compounds, and more specifically, 4-methoxyphenol, N-nitroso-N-phenylhydroxyl. Examples include amine aluminum.

  [H] The amount of the storage stabilizer used is preferably 3.0 parts by mass or less and more preferably 0.5 parts by mass or less with respect to 100 parts by mass of the [A] polymer or [A] copolymer. [H] When the amount of the storage stabilizer exceeds 3.0 parts by mass, the sensitivity of the composition may be lowered and the pattern shape may be deteriorated.

[[I] heat resistance improver]
[I] Examples of the heat resistance improver include N- (alkoxymethyl) glycoluril compounds and N- (alkoxymethyl) melamine compounds.

Examples of N- (alkoxymethyl) glycoluril compounds include N, N, N ′, N′-tetra (methoxymethyl) glycoluril, N, N, N ′, N′-tetra (ethoxymethyl) glycoluril, N , N, N ′, N′-tetra (n-propoxymethyl) glycoluril, N, N, N ′, N′-tetra (i-propoxymethyl) glycoluril, N, N, N ′, N′-tetra (N-Butoxymethyl) glycoluril, N, N ′
, N ″, N ′ ″-tetra (t-butoxymethyl) glycoluril and the like. Of these, N, N, N ′, N′-tetra (methoxymethyl) glycoluril is preferred.

  Examples of N- (alkoxymethyl) melamine compounds include N, N, N ′, N ′, N ″, N ″ -hexa (methoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″. Hexa (ethoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (n-propoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (I-propoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (n-butoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (T-butoxymethyl) melamine and the like. Of these, N, N, N ′, N ′, N ″, N ″ -hexa (methoxymethyl) melamine is preferred, and examples of commercially available products include Nicalac N-2702 and MW-30M (above, Sanwa Chemical). Company).

  [I] The amount of the heat resistance improver used is preferably 50 parts by mass or less and more preferably 30 parts by mass or less with respect to 100 parts by mass of the [A] polymer or [A] copolymer. [I] When the compounding amount of the heat resistance improver exceeds 50 parts by mass, the sensitivity of the composition may be lowered and the pattern shape may be deteriorated.

<Preparation of radiation-sensitive resin composition>
In addition to the [A] polymer or [A] copolymer, the [B] polymerizable compound, the [C] polymerization initiator, and the [D] compound, the radiation sensitive resin composition of the present invention has the desired effect. It is prepared by mixing an arbitrary component at a predetermined ratio as necessary as long as it does not impair. This radiation-sensitive resin composition is preferably used in a solution state after being dissolved in an appropriate solvent.

  As a solvent used for the preparation of the composition, [A] polymer or [A] copolymer, [B] polymerizable compound, [C] polymerization initiator, [D] compound and optional components are uniformly dissolved. Or what is disperse | distributed and does not react with each component is used. Examples of such a solvent include those similar to those exemplified as the solvent that can be used to synthesize the above-mentioned [A] copolymer, but at least selected from the group consisting of alcohol solvents and ether solvents. It preferably contains one solvent. In the said composition, it is thought that the decay | disintegration of inclusion is suppressed by interaction with the carboxyl group in the coexisting [A] copolymer, and a [D] compound, and a polar solvent can be used. Furthermore, it is considered that the [D] compound also has a synergistic effect of accelerating the curing reaction of the epoxy group in the [A] copolymer due to the above interaction. A solvent can be used individually or in mixture of 2 or more types.

  From the viewpoint of solubility of each component, reactivity with each component, ease of film formation, etc., alcohols, glycol ether, ethylene glycol monoalkyl ether acetate, esters, diethylene glycol monoalkyl ether acetate, diethylene glycol dialkyl ether, diethylene glycol Propylene glycol dialkyl ether, propylene glycol monoalkyl ether, and propylene glycol monoalkyl ether acetate are preferred. Among these, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, More preferred are propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl 2- or 3-methoxypropionate, and ethyl 2- or 3-ethoxypropionate.

  Furthermore, in order to improve the in-plane uniformity of the film thickness together with the solvent, a high boiling point solvent can be used in combination. Examples of the high boiling point solvent include N-methylpyrrolidone, N, N-dimethylacetamide, benzyl ethyl ether, dihexyl ether, acetonyl acetone, 1-octanol, 1-nonanol, benzyl acetate, ethyl benzoate, diethyl oxalate, malein Examples include diethyl acid, γ-butyrolactone, and propylene carbonate. Of these, N-methylpyrrolidone, γ-butyrolactone or N, N-dimethylacetamide is preferred.

  When a high boiling point solvent is used in combination as the solvent for the composition, the amount used is preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less, based on the total amount of solvent. . When the amount of the high-boiling solvent used is 50% by mass or less, the film thickness uniformity, sensitivity, and residual film rate are good.

  When the composition is prepared as a solution, the solid content concentration (components other than the solvent in the composition solution) can be set to any concentration (for example, 5% by mass to 5% by mass depending on the purpose of use, the desired film thickness value, etc.). 50% by mass). A more preferable solid content concentration varies depending on the method of forming a film on the substrate, which will be described later. The composition solution thus prepared can be used after being filtered using a Millipore filter or the like having a pore size of about 0.5 μm.

<Method for forming cured film>
Hereinafter, a method for forming a cured film such as an interlayer insulating film, a protective film, or a spacer using the composition will be described.

The method for forming a cured film of the present invention includes at least the following steps (1) to (4) in the order described below.
(1) The process of forming the coating film of the said composition on a board | substrate (2) The process of irradiating at least one part of the coating film formed at the process (1),
(3) A step of developing the coating film irradiated with radiation in step (2), and (4) A step of baking the coating film developed in step (3).

  By the forming method of the present invention using the composition, a cured film satisfying in a well-balanced required characteristics such as heat resistance, chemical resistance, transmittance, flatness, voltage holding ratio, and linear thermal expansion resistance can be formed. Hereinafter, each of these steps will be described in detail.

[(1) Step of forming a coating film of the composition on a substrate]
A transparent conductive film is formed on one side of the transparent substrate, and a film of the radiation sensitive resin composition is formed on the transparent conductive film. Examples of the transparent substrate include glass substrates such as soda lime glass and alkali-free glass, and resin substrates made of plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and polyimide.

As the transparent conductive film provided on one surface of the transparent substrate, a NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) Etc.

  In the case of forming a film by a coating method, the film can be formed by applying a solution of the composition on the transparent conductive film and then heating (pre-baking) the coated surface. As solid content concentration of the composition solution used for a coating method, 5 mass%-50 mass% are preferable, 10 mass%-40 mass% are more preferable, 15 mass%-35 mass% are especially preferable. Examples of the application method of the composition solution include appropriate methods such as a spray method, a roll coating method, a spin coating method (spin coating method), a slit coating method (slit die coating method), a bar coating method, and an ink jet coating method. Can be adopted. Of these, spin coating or slit coating is preferred.

  The prebaking conditions vary depending on the type of each component, the blending ratio, and the like, but are preferably 70 ° C. to 120 ° C. and about 1 to 15 minutes. The film thickness after pre-baking of the coating is preferably 0.5 μm to 10 μm, more preferably about 1.0 μm to 7.0 μm.

[(2) Step of irradiating at least a part of the coating film formed in step (1)]
Next, radiation is applied to at least a part of the formed film. At this time, when irradiating only a part of the film, for example, the irradiation can be performed through a photomask having a predetermined pattern.

  Examples of radiation used for irradiation include visible light, ultraviolet light, and far ultraviolet light. Of these, radiation having a wavelength in the range of 250 nm to 550 nm is preferable, and radiation including ultraviolet light of 365 nm is more preferable.

Radiation dose (exposure dose), as a value measured by a luminometer intensity at a wavelength 365nm of the radiation emitted (OAI model 356, Optical Associates Ltd. ^{Inc.), 100J / m 2 ~5,000J} / m 2 is Preferably, 200 J / m ^{2 to} 3,000 J / m ² is more preferable.

The composition has a higher radiation sensitivity than a conventionally known composition, and the desired film thickness is good even when the radiation dose is 700 J / m ² or less, and even 600 J / m ² or less. It has an advantage that a cured film such as an interlayer insulating film, a protective film or a spacer having a shape, excellent adhesion and high hardness can be obtained.

[(3) Step of developing the coating film irradiated with radiation in step (2)]
Next, by developing the film after irradiation, unnecessary portions are removed to form a predetermined pattern.

  As the developer used for development, for example, an inorganic alkali such as sodium hydroxide, potassium hydroxide or sodium carbonate, or an aqueous solution of an alkaline compound such as a quaternary ammonium salt such as tetramethylammonium hydroxide or tetraethylammonium hydroxide is used. it can. An appropriate amount of a water-soluble organic solvent such as methanol or ethanol and / or a surfactant can be added to the aqueous solution of the alkaline compound.

  The developing method may be any of a liquid filling method, a dipping method, a shower method, and the like, and the developing time is preferably about 10 seconds to 180 seconds at room temperature. Subsequent to the development processing, for example, washing with running water is performed for 30 seconds to 90 seconds, and then a desired pattern is obtained by air drying with compressed air or compressed nitrogen.

[(4) Step of baking the coating film developed in step (3)]
Next, the obtained patterned film is baked (post-baked) with a suitable heating device such as a hot plate or oven to obtain a cured film. As baking temperature, 100 to 200 degreeC is preferable and 150 to 180 degreeC is more preferable. The firing time is preferably, for example, 5 minutes to 30 minutes on a hot plate and 30 minutes to 180 minutes in an oven. Since the composition contains the [D] compound as described above, such low-temperature firing is realized, storage stability is compatible, and sufficient radiation sensitivity is obtained. Therefore, the composition is suitably used as a material for forming a cured film such as an interlayer insulating film, a protective film, and a spacer used in a flexible display or the like where low temperature baking is desired.

<Display element>
The display element of the present invention can be produced, for example, by the following method.

  First, a pair (two) of transparent substrates having a transparent conductive film (electrode) on one side is prepared, and a spacer or a protective film is formed on the transparent conductive film of one of the substrates using the composition according to the method described above. Or both. Subsequently, an alignment film having liquid crystal alignment ability is formed on the transparent conductive film and the spacer or protective film of these substrates. These substrates are arranged facing each other with a certain gap (cell gap) so that the liquid crystal alignment direction of each alignment film is orthogonal or antiparallel, with the surface on which the alignment film is formed inside. A liquid crystal is filled in the cell gap defined by the surface of the substrate (alignment film) and the spacer, and the filling hole is sealed to constitute a liquid crystal cell. Then, the display element of the present invention is bonded to both outer surfaces of the liquid crystal cell such that the polarizing direction is aligned or orthogonal to the liquid crystal alignment direction of the alignment film formed on one surface of the substrate. can get.

  As another method, a pair of transparent substrates on which a transparent conductive film, an interlayer insulating film, a protective film, a spacer, or both, and an alignment film are formed are prepared in the same manner as described above. After that, along the edge of one substrate, an ultraviolet curable sealant is applied using a dispenser, and then the liquid crystal is dropped in the form of fine droplets using a liquid crystal dispenser, and the two substrates are bonded together under vacuum. . Then, both the substrates are sealed by irradiating the sealing agent part with ultraviolet rays using a high-pressure mercury lamp. Finally, the display element of the present invention is obtained by attaching polarizing plates to both outer surfaces of the liquid crystal cell.

  Examples of the liquid crystal used in each of the above methods include nematic liquid crystal and smectic liquid crystal. In addition, as a polarizing plate used outside the liquid crystal cell, a polarizing film in which a polarizing film called an “H film” that absorbs iodine while stretching and aligning polyvinyl alcohol is sandwiched between cellulose acetate protective films, or an H film Examples thereof include a polarizing plate made of itself.

  EXAMPLES Hereinafter, although this invention is explained in full detail based on an Example, this invention is not interpreted limitedly to this Example.

In the following synthesis examples, the weight average molecular weight (Mw) of the copolymer was measured by gel permeation chromatography (GPC) under the following apparatus and conditions.
Equipment: GPC-101 (Showa Denko)
Column: GPC-KF-801, GPC-KF-802, GPC-KF-803 and GPC-KF-804 are combined Mobile phase: Tetrahydrofuran

<Synthesis of [A] copolymer>
[Synthesis Example 1]
A flask equipped with a condenser and a stirrer was charged with 5 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether. Subsequently, 20 parts by mass of styrene, 12 parts by mass of methacrylic acid, 28 parts by mass of dicyclopentanyl methacrylate and 40 parts by mass of glycidyl methacrylate were charged, and the temperature of the solution was raised to 70 ° C. while gently stirring. The solution containing the copolymer (A-1) was obtained by polymerization while maintaining this temperature for 5 hours. The solid content concentration of the obtained copolymer solution was 31.3%, and Mw of the copolymer (A-1) was 12,000. In addition, solid content concentration means the ratio of the copolymer mass which occupies for the total mass of a copolymer solution.

[Synthesis Example 2]
A flask equipped with a condenser and a stirrer was charged with 5 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether. Subsequently, 10 parts by mass of styrene, 12 parts by mass of methacrylic acid, 23 parts by mass of tricyclodicyclopentanyl methacrylate, 20 parts by mass of glycidyl methacrylate, 20 parts by mass of 2-methylglycidyl methacrylate, and 10 parts by mass of tetrahydrofurfuryl methacrylate were charged. After purging with nitrogen, 5 parts by mass of 1,3-butadiene was further added, the temperature of the solution was raised to 70 ° C. while gently stirring, and this temperature was maintained for 5 hours to polymerize, whereby a copolymer was obtained. A solution containing (A-2) was obtained. The solid content concentration of the obtained copolymer solution was 31.5%, and Mw of the copolymer (A-2) was 10,100.

[Synthesis Example 3]
A flask equipped with a condenser and a stirrer was charged with 5 parts by mass of 2,2′-azobis (isobutyronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether. Subsequently, 15 parts by weight of styrene, 30 parts by weight of n-butyl methacrylate, 30 parts by weight of benzyl methacrylate and 25 parts by weight of glycidyl methacrylate were charged and the temperature of the solution was raised to 80 ° C. while gently stirring. The solution containing a copolymer (A-3) was obtained by carrying out polymerization for 5 hours. The solid content concentration of the obtained copolymer solution was 31.0%, and Mw of the copolymer (A-3) was 10,000.

<Preparation of radiation-sensitive resin composition for forming cured film>
[Examples 1 to 14]
The types and amounts of [A] polymer or [A] copolymer, [B] polymerizable compound, [C] polymerization initiator, and [D] compound shown in Table 1 were mixed, and [F] adhesion aid was further mixed. 5 parts by weight of γ-glycidoxypropyltrimethoxysilane as an agent, 0.5 part by weight of [G] surfactant (FTX-218, Neos) and 0.5 parts by weight of 4-methoxyphenol as a [H] storage stabilizer Parts were mixed and each was added with propylene glycol monomethyl ether acetate so that the solid content concentration was 30% by mass, and then filtered through a Millipore filter with a pore size of 0.5 μm to prepare a radiation sensitive resin composition. And Examples 1 to 14 and Comparative Examples 1 to 4, respectively. In addition, “-” in the column represents that the corresponding component was not used.

  Details of the [B] polymerizable compound, the [C] polymerization initiator, and the [D] compound constituting the radiation sensitive resin composition are shown below.

([A] polymer, copolymer)
(A-1) Copolymer obtained in Synthesis Example 1 (A-2) Copolymer obtained in Synthesis Example 2 (A-3) Copolymer obtained in Synthesis Example 3 (A-4) Phenol novolac type epoxy resin ("Epicoat 152" manufactured by Japan Epoxy Resin Co., Ltd.)

([B] polymerizable compound)
(B-1) Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (KAYARAD DPHA (Nippon Kayaku)
(B-2) KAYARAD DPHA-40H
(Nippon Kayaku)
(B-3) 1,9-nonanediol diacrylate (B-4) pentaerythritol tetraacrylate (B-5) trimethylolpropane triacrylate (B-6) ω-carboxypolycaprolactone monoacrylate (Aronix M-53
00, Toagosei)
(B-7) Succinic acid-modified pentaerythritol triacrylate (Aronix TO-7
56, Toagosei)
(B-8) Ethylene oxide modified dipentaerythritol hexaacrylate

([C] polymerization initiator)
(C-1) 1,2-octanedione-1- [4- (phenylthio)-, 2- (O-benzoyloxime)] (Irgacure OXE01, Ciba Specialty Chemicals)
(C-2) Ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime) (Irgacure OXE02, Ciba Specialty Chemicals) Company)
(C-3) 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (Irgacure 907, Ciba Specialty Chemicals)
(C-4) 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one (Irgacure 379, Ciba Specialty Chemicals) )

([D] Compound)
(D-1) Acetamide (D-2) N-methylacetamide (D-3) Phthalamic acid (D-4) Isophthalamide (D-5) Adipinamide (D-6) N, N′-Diacetyl-p- Phenylenediamine (D-7) N, N′-diacetyl-hexamethylenediamine Comparative Example Amine Compound (d-1) Triethylamine

表中、「−」は添加しなかったことを示す。

In the table, “-” indicates that no addition was made.

<Evaluation>
The radiation sensitive resin composition was evaluated as follows. The results are shown in Table 2.

[Measurement of storage stability (%)]
The radiation-sensitive composition was left in an oven at 40 ° C. for 1 week, and the viscosity before and after being placed in the oven was measured to determine the rate of change in viscosity. At this time, when the viscosity change rate is 5% or less, the storage stability is good, and when it exceeds 5%, the storage stability is poor. The viscosity was measured at 25 ° C. using an E-type viscometer (VISCONIC ELD.R, Toki Sangyo Co., Ltd.).

[Measurement of sensitivity (J / m ² )]
The radiation-sensitive resin composition was applied onto an alkali-free glass substrate with a spinner, and then prebaked on a hot plate at 100 ° C. for 2 minutes to form a film having a thickness of 4.0 μm.
Next, an exposure dose of 200 J / m ^{2 to} 1,000 J is applied to the obtained coating film using a high-pressure mercury lamp through a photomask having a plurality of circular residual patterns having different sizes ranging from 8 μm to 15 μm in diameter. Irradiation was performed with a variable amount in the range of / m ² . Thereafter, development was performed by a puddle method using a 0.40 mass% tetramethylammonium hydroxide aqueous solution at 25 ° C. with a development time as a variable, and then washing with pure water was performed for 1 minute. Further, post-baking was carried out at 180 ° C. for 60 minutes in an oven to form a cured film having a round residue pattern.
The height of the circular residual pattern before and after development was measured using a laser microscope (VK-8500, Keyence Corporation). The residual film ratio (%) was determined from this value and the following formula.
Residual film ratio (%) = (height after development / height before development) × 100
The exposure amount at which the remaining film ratio was 90% or more was defined as sensitivity. It can be said that the sensitivity is good when the exposure amount is 800 J / m ² or less.

[Measurement of heat resistance (%)]
In the above cured film forming step, the film obtained by exposing at an exposure amount of 700 J / m ² without passing through a photomask and further post-baking at 180 ° C. for 60 minutes in an oven, and further at 230 ° C. in an oven. Measure the film thickness before and after heating for 20 minutes with a stylus type film thickness measuring machine (Alphastep IQ, KLA Tencor) and calculate the residual film ratio (film thickness after treatment / film thickness before treatment x 100). The residual film ratio was regarded as heat resistance.

[Measurement of chemical resistance (%)]
In the above cured film forming step, the film obtained by exposure at an exposure amount of 700 J / m ² without passing through a photomask and post-baking at 180 ° C. for 60 minutes in an oven was heated to 60 ° C. The film was immersed in an alignment film stripping solution Chemiclean TS-204 (Sanyo Kasei Kogyo Co., Ltd.) for 15 minutes, washed with water, and further dried in an oven at 120 ° C. for 15 minutes. The film thickness before and after this treatment was measured with a stylus type film thickness measuring machine (Alphastep IQ, KLA Tencor), and the remaining film ratio (film thickness after treatment / film thickness before treatment × 100) was calculated. The film rate was defined as chemical resistance.

[Measurement of transmittance (%)]
In the above cured film forming step, the film obtained by exposing with an exposure amount of 700 J / m ² without passing through a photomask and further post-baking at 180 ° C. for 60 minutes in an oven has a transmittance at a wavelength of 400 nm. And a spectrophotometer (150-20 type double beam, Hitachi, Ltd.). At this time, when the transmittance was less than 90%, the transparency was regarded as poor.

[Measurement of flatness (nm)]
Using a pigment-based color resist (JCR RED 689, JCR GREEN 706, and CR 8200B, JSR) on a SiO ₂ dip glass substrate, the following three stripe colors of red, green, and blue are used. A filter was formed. Specifically, one color of the color resist was applied to a SiO ₂ dip glass substrate using a spinner and pre-baked on a hot plate at 90 ° C. for 150 seconds to form a coating film. Thereafter, using an exposure machine (Canon PLA501F, Canon Inc.), the ghi line (intensity ratio of wavelengths 436 nm, 405 nm, 365 nm = 2.7: 2.5: 4.8) is passed through the predetermined pattern mask. Irradiation was performed at an exposure amount of 2,000 J / m ^{2 in} terms of conversion, followed by development using a 0.05 mass% aqueous potassium hydroxide solution and rinsing with ultrapure water for 60 seconds. Subsequently, a heat treatment was further performed in an oven at 230 ° C. for 30 minutes to form a single-color striped color filter. By repeating this operation for three colors, a striped color filter (stripe width 200 μm) of three colors of red, green and blue was formed.
Measurement length 2,000μm, measurement range 2,000μm square, measurement direction is red, green, blue stripe line minor axis direction and red / red, green / green, blue / blue same color stripe line major axis direction Measure unevenness on the surface of the color filter substrate with a contact-type film thickness measuring device (Alpha-Step, KLA-Tencor Corporation) with two directions and the number of measurement points n = 5 (total n number is 10) in each direction. As a result, it was 1.0 μm. Each thermosetting resin composition was applied to the substrate on which the color filter was formed with a spinner, then pre-baked on a hot plate at 90 ° C. for 5 minutes to form a coating film, and further in a clean oven Then, a protective film having a thickness of about 2.0 μm from the upper surface of the color filter was formed by post-baking at 180 ° C. for 60 minutes.
With respect to the substrate having the protective film on the color filter formed in this manner, the unevenness of the surface of the protective film was measured with a contact-type film thickness measuring device (Alpha-Step, KLA Tencor). This measurement has a measuring length of 2,000 μm, a measuring range of 2,000 μm square, measuring directions of red, green, blue stripe lines and minor axis directions, and red / red, green / green, blue / blue stripe lines of the same color. Two major axis directions are used, and the number of measurement points is n = 5 (total n number is 10) in each direction, and the average value of 10 times of the height difference (nm) between the highest part and the lowest part of each measurement is obtained. Table 2 shows the evaluation of the flattening ability (flatness) of the protective film. When this value is 200 nm or less, it can be said that the planarization ability of the protective film is good.

[Measurement of linear thermal expansion coefficient (ppm / ° C)]
In the cured film forming step, exposure was performed at an exposure amount of 700 J / m ² without using a photomask to form a coating film. Thereafter, a film for measurement was produced by heating and curing in an oven at 180 ° C. for 60 minutes. Next, for this film, an ellipsometer (DVA-36LH, Mizojiri Optical Co., Ltd.) equipped with a temperature variable device was used to measure the temperature rise rate during measurement at 10 ° C./min and the measurement temperature range from 20 ° C. to 20 ° C. The amount of change in film thickness at each measurement temperature was measured at 200 ° C., plotted against temperature, the slope b was determined from the linear approximation, and the linear thermal expansion coefficient a was determined from the following equation. T represents the initial film thickness.
a = b / T
When the linear thermal expansion coefficient is 200 ppm / ° C. or less, it can be determined that a cured film having a low linear thermal expansion coefficient and having sufficient curability even after post-baking at 180 ° C. has been produced.

[Measurement of voltage holding ratio (%)]
The radiation sensitive resin composition was spin-coated on a soda glass substrate on which a SiO ₂ film for preventing elution of sodium ions was formed on the surface, and an ITO (indium-tin oxide alloy) electrode was deposited in a predetermined shape. After that, pre-baking was performed for 10 minutes in a clean oven at 90 ° C. to form a coating film having a thickness of 2.0 μm.
Then, without going through a photomask


The coating film was exposed with an exposure amount of 500 J / m ² . Thereafter, the substrate is immersed in a developer composed of 0.04 mass% potassium hydroxide aqueous solution at 23 ° C. for 1 minute, developed, washed with ultrapure water, air-dried, and further post-treated at 180 ° C. for 60 minutes. Baking was performed and the coating film was cured to form a permanent cured film.
Next, the substrate on which this pixel is formed and the substrate on which ITO electrodes are simply deposited in a predetermined shape are bonded together with a sealing agent mixed with 0.8 mm glass beads, and then liquid crystal made by Merck (MLC6608) is injected. A liquid crystal cell was produced.
Next, the liquid crystal cell was placed in a constant temperature layer at 60 ° C., and the voltage holding ratio of the liquid crystal cell was measured by a liquid crystal voltage holding ratio measuring system (VHR-1A type, Toyo Technica Co., Ltd.). The applied voltage at this time is a square wave of 5.5 V, and the measurement frequency is 60 Hz. Here, the voltage holding ratio is a value of (liquid crystal cell potential difference after 16.7 milliseconds / voltage applied at 0 milliseconds). If the voltage holding ratio of the liquid crystal cell is 90% or less, it means that the liquid crystal cell cannot hold the applied voltage at a predetermined level for a time of 16.7 milliseconds, and the liquid crystal cannot be sufficiently aligned. There is a high risk of causing “burn-in”.

  From the results of Table 2, it was found that the compositions of Examples 1 to 15 had better storage stability and radiation sensitivity than the compositions of Comparative Examples 1 to 4. Moreover, although the cured film formed from the said composition of Examples 1-14 was formed by low-temperature baking below 200 degreeC, heat resistance, chemical resistance, transmittance | permeability, flatness, linear thermal expansion It was found to be excellent in properties. Furthermore, the voltage holding ratio of the display element having the cured film was also good.

  The radiation-sensitive resin composition of the present invention can easily form a fine and elaborate pattern, achieves both storage stability and low-temperature firing, and has sufficient radiation sensitivity. Moreover, the cured film formed from the composition is excellent in the required properties such as heat resistance, chemical resistance, transmittance, flatness, voltage holding ratio, and linear thermal expansion resistance. Therefore, the composition is suitably used as a material for forming a cured film such as an interlayer insulating film, a protective film, or a spacer used in a flexible display or the like where low-temperature firing is desired.

Claims (7)

[A] a polymer having an epoxy group,
[B] a polymerizable compound having an ethylenically unsaturated bond,
A radiation-sensitive resin composition comprising [C] a radiation-sensitive polymerization initiator and [D] at least one compound selected from compounds represented by the following formulas (1) to (3): .

(In the formula ^{(1), R 1, R} 2 are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cyclohexyl group, a phenyl group, a naphthyl group, a vinyl group, a 2-pyridyl group or a carbon An alkyl group having 1 to 6 carbon atoms, a halogen group, a hydroxyl group, a carboxyl group, or an acetyl group which may be substituted with an alkyl group, a phenyl group or a naphthyl group.
In formula (2), R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyclohexyl group, and A is a methylene group, an alkylene group having 2 to 12 carbon atoms, or a phenylene group. , A naphthylene group, a vinylene group, or an alkyl group having 1 to 6 carbon atoms, a methylene group that may be substituted with a halogen, an alkylene group having 2 to 12 carbon atoms, a phenylene group, or a naphthylene group.
In formula (3), R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyclohexyl group, and A is a methylene group, an alkylene group having 2 to 12 carbon atoms, or a phenylene group. , A naphthylene group, a vinylene group, or an alkyl group having 1 to 6 carbon atoms, a methylene group that may be substituted with a halogen, an alkylene group having 2 to 12 carbon atoms, a phenylene group, or a naphthylene group. ) The radiation-sensitive resin composition according to claim 1, wherein the polymer having an epoxy group is a polymer further having a carboxyl group.   The radiation-sensitive resin composition according to claim 1 or 2, wherein the [C] radiation-sensitive polymerization initiator is at least one selected from the group consisting of an acetophenone compound and an O-acyloxime compound. (1) The process of forming the coating film of the radiation sensitive resin composition of Claim 1 to Claim 3 on a board | substrate,
(2) A step of irradiating at least a part of the coating film formed in step (1),
(3) A step of developing the coating film irradiated with radiation in step (2), and (4) a step of baking the coating film developed in step (3).   The forming method according to claim 4, wherein the firing temperature in the step (4) is 200 ° C. or less.   A cured film as an interlayer insulating film, protective film or spacer formed from the radiation-sensitive resin composition according to claim 1.   A display element provided with the cured film of Claim 6.