JP2009001653A - Side chain unsaturated polymer, radiation sensitive resin composition, and spacer for liquid crystal display device - Google Patents

Abstract

（式中、Ｒ_１は水素原子またはメチル基であり、Ｒ_２はエチレン基またはプロピレン基であり、ｎは１〜５の整数である。）
【選択図】なし[PROBLEMS] To provide a high-sensitivity, sufficient spacer shape even at an exposure amount of 1,000 J / m ² or less, rubbing resistance, adhesion to a transparent substrate, heat resistance, spacer flexibility, and radiation-sensitive resin composition. It is intended to provide a radiation-sensitive resin composition capable of forming a spacer for a liquid crystal display element having excellent storage stability, a polymer useful as a component of the composition, and the like.
The polymer comprises (a1) at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, and (a2) an unsaturated compound containing one or more hydroxyl groups in one molecule. It is obtained by reacting a compound represented by the following formula (1) with a copolymer of the compound. The radiation sensitive resin composition contains the polymer, a polymerizable unsaturated compound, and a radiation sensitive polymerization initiator.
[Chemical 1]

(In the formula, R ₁ is a hydrogen atom or a methyl group, R ₂ is an ethylene group or a propylene group, and n is an integer of 1 to 5.)
[Selection figure] None

Description

  The present invention relates to a polymer particularly suitable for forming a spacer in a liquid crystal display device, a radiation-sensitive resin composition containing the polymer, a spacer, a method for forming the spacer, and a liquid crystal display device.

Conventionally, spacers such as glass beads and plastic beads having a predetermined particle diameter have been used for liquid crystal display elements in order to keep the distance (cell gap) between two substrates constant. Is scattered randomly on a transparent substrate such as a glass substrate, and if a spacer is present in the pixel formation region, the reflection of the spacer occurs or the incident light is scattered to reduce the contrast as a liquid crystal display element. There was a problem.
Therefore, in order to solve such a problem, a method of forming a spacer by photolithography has been adopted. In this method, a radiation-sensitive resin composition is applied onto a substrate, exposed to, for example, ultraviolet rays through a predetermined mask, and then developed to form a dot-like or stripe-like spacer. Since the spacer can be formed only at a predetermined place other than the above, the above-described problem is basically solved.

In recent years, the mother glass substrate has been increased in size (for example, about 1500 × 1800 mm and further about 1870 × 2200 mm) from the viewpoint of increasing the area of the liquid crystal display element and improving productivity. However, with the conventional substrate size, the substrate size is smaller than the mask size, so it was possible to cope with the batch exposure method. However, with a large substrate, it is almost impossible to produce a mask size comparable to this substrate size. It is possible, and it is difficult to cope with the batch exposure method.
Therefore, a step exposure method has been proposed as an exposure method that can be applied to a large substrate. However, in the step exposure method, since a single substrate is exposed several times, and each exposure requires time for alignment and step movement, the throughput is reduced as compared with the batch exposure method. Therefore, there is a demand for high sensitivity to the radiation-sensitive resin composition.

Further, in the batch exposure method, an exposure amount of about 3,000 J / m ² is possible, but in the step exposure method, it is necessary to lower the exposure amount each time, and the conventional exposure method used for forming the spacer is used. In the radiation sensitive resin composition, it has been difficult to achieve a sufficient spacer shape and film thickness with an exposure dose of 1,000 J / m ² or less.
Further, when a defect occurs in the process as the substrate becomes larger, it is necessary to peel off the alignment film formed on the color filter and reuse it. An alkaline aqueous stripping solution is used for stripping the alignment film, but the spacer needs to be resistant to the stripping solution. That is, it is desirable that the lower spacer does not change in thickness due to swelling or dissolution when the alignment film is peeled off, and physical properties such as elastic properties are required to exhibit the same properties as before peeling.

In the conventional bonding method, since a load is applied when the TFT array and the color filter are bonded, the spacer is evenly pressed by the load, and the height uniformity of the spacer is maintained. However, in the ODF method, the initial bonding load is smaller than the conventional method because the bonding is performed only by the load due to the weight of the substrate and the atmospheric pressure. Therefore, even if the spacer is pushed with a small load, it is important to develop height uniformity by being pushed evenly. For this purpose, the flexibility of the spacer is required. If the height of the spacer is not uniform, the cell gap cannot be kept uniform, causing a gap in the cell and causing display unevenness.

  In Patent Document 1, Patent Document 2 and Patent Document 3, a photopolymerizable functional group in which a (meth) acryloyloxyalkyl isocyanate compound is reacted with a copolymerizable resin having a hydroxyl group in the photosensitive resin composition is constituted. It is said that the use of a copolymer resin as a unit can achieve improvement in performance as a spacer and protective film such as high sensitivity and chemical resistance. An epoxy resin having two or more epoxy groups in the molecule for the purpose of improving the heat resistance of the spacer and the protective film, adhesion to the substrate, chemical resistance, in particular, the resistance to the alignment film peeling solution and the aqueous alkali solution. Used. However, there is a concern about the storage stability of the photosensitive resin composition and the solubility in a developer by adding this epoxy resin.

JP 2000-105456 A JP 2000-171804 A JP 2000-298339 A

Therefore, the object of the present invention is to obtain a sufficient spacer shape with high sensitivity even at an exposure amount of 1,000 J / m ² or less, rubbing resistance, adhesion to a transparent substrate, heat resistance, spacer flexibility, sensitivity. An object of the present invention is to provide a radiation-sensitive resin composition capable of forming a spacer for a liquid crystal display device having excellent storage stability of the radiation-sensitive resin composition.

  Another object of the present invention is to provide a polymer useful as a resin component of the radiation-sensitive resin composition.

  Still another object of the present invention is to provide a liquid crystal display spacer formed from the above radiation sensitive resin composition and a liquid crystal display element including the same.

  Still another object of the present invention is to provide a method for forming the above-mentioned liquid crystal display spacer.

According to the present invention, the problem is firstly
The polymer main chain is composed of a monomer containing at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, and a group represented by the following formula (1) on the polymer side chain It is achieved by a polymer characterized by having

(In Formula (1), R ₁ is a hydrogen atom or a methyl group, R ₂ is an ethylene group or a propylene group, n is an integer of 1 to 5. “*” is a bond. Is shown.)

According to the present invention, the problem is secondly,
[A] A radiation-sensitive resin composition (hereinafter referred to as “radiation-sensitive resin composition”), which contains the polymer, [B] a polymerizable unsaturated compound, and [C] a radiation-sensitive polymerization initiator. ").

According to the present invention, the problem is thirdly,
This is achieved by a spacer for a liquid crystal display element formed from the radiation sensitive resin composition.

According to the present invention, the problem is fourthly,
This is achieved by a method for forming a spacer for a liquid crystal display element, comprising at least the following steps in the order described below.
(A) forming a film of the radiation sensitive resin composition on a substrate;
(B) exposing at least a part of the coating;
(C) a step of developing the coated film after exposure, and (d) a step of heating the coated film after development.

According to the present invention, fifthly, the problem is as follows:
This is achieved by a liquid crystal display element comprising the liquid crystal display element spacer.

The polymer of the present invention has a reactive unsaturated group in the polymer side chain, and is particularly preferably used as a constituent of a radiation sensitive resin composition used for forming a spacer for a liquid crystal display element. It is also useful as a constituent material for radiation-sensitive resin compositions used for forming protective films for liquid crystal display elements, radiation-sensitive resin compositions for forming colored layers, radiation-curable paints, radiation-curable adhesives, etc. It is.
The radiation sensitive resin composition of the present invention has high sensitivity and high resolution, and a sufficient pattern shape can be obtained even at an exposure amount of 1,000 J / m ² or less, and the radiation sensitive resin composition has excellent storage stability, A spacer for a liquid crystal display element having excellent flexibility, rubbing resistance, adhesion to a transparent substrate, heat resistance and the like can be formed.
The liquid crystal display element of the present invention comprises a spacer having excellent performance such as sensitivity, elastic recovery, flexibility, rubbing resistance, adhesion to a transparent substrate, heat resistance, etc., and has high reliability over a long period of time. Can be expressed.

Hereinafter, the present invention will be described in detail.
Polymer The polymer of the present invention has at least one polymer main chain selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride (hereinafter these are collectively referred to as “(a1) unsaturated carboxylic acid series”. A polymer (hereinafter referred to as “[A] polymer”) having a group represented by the formula (1) in the polymer side chain. .).

[A] The polymer is, for example, a copolymer of (a1) an unsaturated carboxylic acid compound and an unsaturated compound containing one or more hydroxyl groups or amino groups in one molecule represented by the following formula (2). It can be obtained by reacting the compound represented (hereinafter referred to as “unsaturated isocyanate compound (1)”). Preferred [A] polymers in the present invention include, for example, a copolymer of (a1) an unsaturated carboxylic acid compound and (a2) an unsaturated compound containing one or more hydroxyl groups in one molecule (hereinafter referred to as “a”). , "Copolymer [α]") and a polymer obtained by reacting the unsaturated isocyanate compound (1).

(In the formula _(2), R 1, _{R 2} and n have the same meanings as _R 1, _{R 2} and n in each formula (1).)

Among the components constituting the copolymer [α], as the (a1) unsaturated carboxylic acid compound, for example,
Monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxyethyl hexahydrophthalic acid;
Dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid;
The acid anhydride of the said dicarboxylic acid etc. can be mentioned.

Among these (a1) unsaturated carboxylic acid-based compounds, acrylic acid, methacrylic acid, maleic anhydride are available from the viewpoints of copolymerization reactivity, solubility of the resulting [A] polymer in an alkaline developer and easy availability. An acid or the like is preferable.
In the copolymer [α], the (a1) unsaturated carboxylic acid compound can be used alone or in admixture of two or more.
In the copolymer [α], the content of the repeating unit derived from the (a1) unsaturated carboxylic acid compound is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, and particularly preferably 15 to 30%. % By weight. In this case, when the content of the repeating unit derived from the (a1) unsaturated carboxylic acid compound is less than 5% by weight, the solubility of the polymer obtained by the reaction with the unsaturated isocyanate compound (1) in the alkaline developer is high. On the other hand, if it exceeds 50% by weight, the solubility of the polymer in an alkaline developer may become too high.

(A2) Examples of unsaturated compounds containing one or more hydroxyl groups in one molecule include acrylic acid 2-hydroxyethyl ester, acrylic acid 3-hydroxypropyl ester, acrylic acid 4-hydroxybutyl ester, acrylic Acid 5-hydroxypentyl ester, acrylic acid 6-hydroxyhexyl ester, acrylic acid 7-hydroxyheptyl ester, acrylic acid 8-hydroxyoctyl ester, acrylic acid 9-hydroxynonyl ester, acrylic acid 10-hydroxydecyl ester, acrylic acid 11 -Hydroxy undecyl esters, acrylic acid hydroxyalkyl esters such as acrylic acid 12-hydroxy dodecyl ester;
Methacrylic acid 2-hydroxyethyl ester, Methacrylic acid 3-hydroxypropyl ester, Methacrylic acid 4-hydroxybutyl ester, Methacrylic acid 5-hydroxypentyl ester, Methacrylic acid 6-Hydroxyhexyl ester, Methacrylic acid 7-Hydroxyheptyl ester, Methacrylic acid Methacrylic acid hydroxyalkyl esters such as 8-hydroxyoctyl ester, methacrylic acid 9-hydroxynonyl ester, methacrylic acid 10-hydroxydecyl ester, methacrylic acid 11-hydroxyundecyl ester, methacrylic acid 12-hydroxydodecyl ester;
Acrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester, acrylic acid 3- (6-hydroxyhexanoyloxy) propyl ester, acrylic acid 4- (6-hydroxyhexanoyloxy) butyl ester, acrylic acid 5- ( 6-hydroxyhexanoyloxy) pentyl ester, acrylic acid (6-hydroxyhexanoyloxy) alkyl ester such as acrylic acid 6- (6-hydroxyhexanoyloxy) hexyl ester;
Methacrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester, methacrylic acid 3- (6-hydroxyhexanoyloxy) propyl ester, methacrylic acid 4- (6-hydroxyhexanoyloxy) butyl ester, methacrylic acid 5- ( Methacrylic acid (6-hydroxyhexanoyloxy) alkyl esters such as 6-hydroxyethylhexanoyloxy) pentyl ester, methacrylic acid 6- (6-hydroxyhexanoyloxy) hexyl ester;
Commercial products of a mixture of methacrylic acid (6-hydroxyhexanoyloxy) alkyl ester and methacrylic acid 2-hydroxyethyl ester include PLACEL FM1D and FM2D (manufactured by Daicel Chemical Industries, Ltd.) under the trade names. it can.
Acrylic acid 2- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -ethyl ester, acrylic acid 3- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -propyl ester, acrylic acid 4- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -butyl ester, acrylic acid 5- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -pentyl ester, acrylic acid 6- (3 Acrylic acid (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -alkyl ester such as -hydroxy-2,2-dimethyl-propoxycarbonyloxy) -hexyl ester;
Methacrylic acid 2- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -ethyl ester, methacrylic acid 3- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -propyl ester, methacrylic acid 4- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -butyl ester, methacrylic acid 5- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -pentyl ester, methacrylic acid 6- (3-hydroxy And methacrylic acid (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -alkyl ester such as -2,2-dimethyl-propoxycarbonyloxy) -hexyl ester.
As a commercial product of a mixture of (meth) acrylic acid (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -alkyl ester and methacrylic acid 2-hydroxyethyl ester, HEMAC1 (Daicel Chemical Industries, Ltd. )) And the like.
Further, acrylic acid 4-hydroxy-cyclohexyl ester, acrylic acid 4-hydroxymethyl-cyclohexyl methyl ester, acrylic acid 4-hydroxyethyl-cyclohexyl ethyl ester, acrylic acid 3-hydroxy-bicyclo [2.2.1] hept-5 -En-2-yl ester, acrylic acid 3-hydroxymethyl-bicyclo [2.2.1] hept-5-en-2-ylmethyl ester, acrylic acid 3-hydroxyethyl-bicyclo [2.2.1] Hept-5-en-2-ylethyl ester, acrylic acid 8-hydroxy-bicyclo [2.2.1] hept-5-en-2-yl ester, acrylic acid 2-hydroxy-octahydro-4,7-methano -Inden-5-yl ester, 2-hydroxymethyl-octahydro-4,7-metaacrylate -Inden-5-ylmethyl ester, acrylic acid 2-hydroxyethyl-octahydro-4,7-methano-inden-5-ylethyl ester, acrylic acid 3-hydroxy-adamantan-1-yl ester, acrylic acid 3-hydroxy Acrylic acid hydroxyalkyl esters having an alicyclic structure such as methyl-adamantan-1-ylmethyl ester, acrylic acid 3-hydroxyethyl-adamantan-1-ylethyl ester;
Methacrylic acid 4-hydroxy-cyclohexyl ester, Methacrylic acid 4-hydroxymethyl-cyclohexyl methyl ester, Methacrylic acid 4-hydroxyethyl-cyclohexyl ethyl ester, Methacrylic acid 3-hydroxy-bicyclo [2.2.1] Hept-5-ene 2-yl ester, methacrylic acid 3-hydroxymethyl-bicyclo [2.2.1] hept-5-en-2-ylmethyl ester, methacrylic acid 3-hydroxyethyl-bicyclo [2.2.1] hept- 5-En-2-ylethyl ester, methacrylic acid 8-hydroxy-bicyclo [2.2.1] hept-5-en-2-yl ester, methacrylic acid 2-hydroxy-octahydro-4,7-methano-indene -5-yl ester, 2-hydroxymethyl-octahydro-4 methacrylate 7-methano-inden-5-ylmethyl ester, methacrylic acid 2-hydroxyethyl-octahydro-4,7-methano-inden-5-ylethyl ester, methacrylic acid 3-hydroxy-adamantan-1-yl ester, methacrylic acid Methacrylic acid hydroxyalkyl esters having an alicyclic structure such as 3-hydroxymethyl-adamantan-1-ylmethyl ester, methacrylic acid 3-hydroxyethyl-adamantan-1-ylethyl ester;
Acrylic acid 1,2-dihydroxyethyl ester, acrylic acid 2,3-dihydroxypropyl ester, acrylic acid 1,3-dihydroxypropyl ester, acrylic acid 3,4-dihydroxybutyl ester, acrylic acid 3- [3- (2, Dihydroxyalkyl esters of acrylic acid such as 3-dihydroxypropoxy) -2-hydroxypropoxy] -2-hydroxypropyl ester;
Methacrylic acid 1,2-dihydroxyethyl ester, methacrylic acid 2,3-dihydroxypropyl ester, methacrylic acid 1,3-dihydroxypropyl ester, methacrylic acid 3,4-dihydroxybutyl ester, methacrylic acid 3- [3- (2, And methacrylic acid dihydroxyalkyl esters such as 3-dihydroxypropoxy) -2-hydroxypropoxy] -2-hydroxypropyl ester.

Among these unsaturated compounds containing one or more hydroxyl groups in one molecule, acrylic acid 2-hydroxyethyl ester, acrylic acid 3-hydroxypropyl ester, from the viewpoint of copolymerization reactivity and reactivity with isocyanate compounds Acrylic acid 4-hydroxybutyl ester, methacrylic acid 2-hydroxyethyl ester, methacrylic acid 3-hydroxypropyl ester, methacrylic acid 4-hydroxybutyl ester, acrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester, methacrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester, acrylic acid 2- (3-hydroxy-2,2-dimethyl-propoxycarbonyloxy) -ethyl ester, methacrylic acid 2- (3-hydroxy-2,2-dimethyl) -Propoxyl Nyloxy) -ethyl ester, acrylic acid 4-hydroxymethyl-cyclohexyl methyl ester, methacrylic acid 4-hydroxymethyl-cyclohexyl methyl ester, acrylic acid 3-hydroxymethyl-adamantan-1-ylmethyl ester, methacrylic acid 3-hydroxymethyl- Adamantan-1-ylmethyl ester, acrylic acid 2,3-dihydroxypropyl ester, methacrylic acid 2,3-dihydroxypropyl ester and the like are preferable.

In the copolymer [α], (a2) unsaturated compounds containing one or more hydroxyl groups in one molecule can be used alone or in admixture of two or more.
In the copolymer [α], (a2) the content of repeating units derived from an unsaturated compound containing one or more hydroxyl groups in one molecule is preferably 1 to 50% by weight, more preferably 3 to 40%. % By weight, particularly preferably 5 to 30% by weight. In this case, (a2) When the content of the repeating unit derived from the unsaturated compound containing one or more hydroxyl groups in one molecule is less than 1% by weight, the introduction rate of the unsaturated isocyanate compound (1) into the polymer However, when it exceeds 50% by weight, the storage stability of the polymer obtained by the reaction with the unsaturated isocyanate compound (1) tends to be lowered.

In the copolymer [α], unsaturated compounds other than (a1) and (a2) (hereinafter referred to as “(a3) other unsaturated compounds”) can be used as a component of the copolymer. . As a specific example, for example,
Alkyl acrylates such as methyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, sec-butyl acrylate, t-butyl acrylate;
Alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate;
Acrylic acid epoxy such as glycidyl acrylate, 2-methylglycidyl acrylate, 4-hydroxybutyl acrylate glycidyl ether, 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate, 3,4-epoxycyclohexyl acrylate (Cyclo) alkyl esters;
Methacrylic acid such as glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate Acid epoxy (cyclo) alkyl esters;
α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylate glycidyl, α-ethyl acrylate 6,7-epoxyheptyl, α-ethyl acrylate 3,4-epoxycyclohexyl, etc. Other α-alkyl acrylic acid epoxy (cyclo) alkyl esters;
glycidyl ethers such as o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether;
3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, 3- (methacryloyloxymethyl) -2-methyloxetane, 3- (methacryloyloxymethyl) -2-trifluoromethyloxetane, 3- (methacryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (methacryloyloxymethyl) -2-phenyloxetane, 3- (methacryloyloxymethyl) -2,2-difluorooxetane, 3- (methacryloyloxymethyl) ) -2,2,4-trifluorooxetane, 3- (methacryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -3 -Ethyloxy Tan, 2-ethyl-3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -2-trifluoromethyloxetane, 3- (methacryloyloxyethyl) -2-pentafluoroethyloxetane, 3- (methacryloyloxy) Ethyl) -2-phenyloxetane, 2,2-difluoro-3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -2,2,4-trifluorooxetane, 3- (methacryloyloxyethyl) -2 Methacrylic acid esters such as 1,2,4,4-tetrafluorooxetane;
3- (acryloyloxymethyl) oxetane, 3- (acryloyloxymethyl) -3-ethyloxetane, 3- (acryloyloxymethyl) -2-methyloxetane, 3- (acryloyloxymethyl) -2-trifluoromethyloxetane, 3- (acryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (acryloyloxymethyl) -2-phenyloxetane, 3- (acryloyloxymethyl) -2,2-difluorooxetane, 3- (acryloyloxymethyl) ) -2,2,4-trifluorooxetane, 3- (acryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -3 -Ethyloxetane, 2-ethyl-3 (Acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -2-trifluoromethyloxetane, 3- (acryloyloxyethyl) -2-pentafluoroethyloxetane, 3- (acryloyloxyethyl) -2-phenyloxetane, 2,2-difluoro-3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -2,2,4-trifluorooxetane, 3- (acryloyloxyethyl) -2,2,4,4-tetra Acrylic esters such as fluorooxetane;
Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decane-8-yl acrylate, 2- (tricyclo [5.2.1.0 ^2,6 ] acrylate Acrylic alicyclic esters such as decan-8-yloxy) ethyl, isobornyl acrylate;
Cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decanoyl methacrylate, 2- (tricyclo [5.2.1.0 ^2,6 ] methacrylate) Decane-8-yloxy) ethyl, methacrylic acid alicyclic esters such as isobornyl methacrylate;
Aryl esters or aralkyl esters of acrylic acid such as phenyl acrylate and benzyl acrylate;
Aryl esters or aralkyl esters of methacrylic acid such as phenyl methacrylate and benzyl methacrylate;
Unsaturated dicarboxylic acid dialkyl esters such as diethyl maleate, diethyl fumarate, diethyl itaconate;
Acrylic acid ester having an oxygen-containing hetero 5-membered ring or an oxygen-containing hetero 6-membered ring such as tetrahydrofuran-2-yl acrylate, tetrahydropyran-2-yl acrylate, 2-methyltetrahydropyran-2-yl acrylate;
Methacrylic acid ester having an oxygen-containing hetero 5-membered ring or an oxygen-containing hetero 6-membered ring such as tetrahydrofuran-2-yl methacrylate, tetrahydropyran-2-yl methacrylate, 2-methyltetrahydropyran-2-yl methacrylate;
Vinyl aromatic compounds such as styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene;
Unsaturated imides such as maleimide, N-phenylmaleimide, N-cyclohexylmaleimide;
In addition to conjugated diene compounds such as 1,3-butadiene, isoprene and 2,3-dimethyl-1,3-butadiene,
Examples include acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinylidene chloride, and vinyl acetate.

Of these (a3) other unsaturated compounds, n-butyl methacrylate, methyl glycidyl methacrylate, 2-methacrylic acid 2- Methyl glycidyl, 3,4-epoxycyclohexylmethyl methacrylate, 3-methyl-3- (meth) acryloxymethyloxetane, 3-ethyl-3- (meth) acryloxymethyloxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, benzyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, styrene, p-methoxystyrene, tetrahydrofuran-2-yl methacrylate, 1,3- Butadiene is preferred.

In the copolymer [α], (a3) other unsaturated compounds can be used alone or in admixture of two or more.
In the copolymer [α], the content of the repeating unit derived from (a3) another unsaturated compound is preferably 10 to 75% by weight, more preferably 20 to 70% by weight, particularly preferably 30 to 65% by weight. %. In this case, when the content of the repeating unit derived from (a3) another unsaturated compound is less than 10% by weight, the storage stability of the polymer obtained by the reaction with the unsaturated isocyanate compound (1) tends to decrease. On the other hand, if it exceeds 75% by weight, the solubility of the polymer in an alkaline developer tends to decrease.

  The copolymer [α] is prepared by, for example, (a1) unsaturated carboxylic acid compound, (a2) hydroxyl group-containing unsaturated compound and (a3) other unsaturated compound in the presence of a radical polymerization initiator in a suitable solvent. It can manufacture by polymerizing under.

As the solvent used for the polymerization, for example,
Alcohols such as methanol, ethanol, n-propanol, i-propanol;
Ethers such as tetrahydrofuran and dioxane;
Ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether;
Ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether acetate, ethylene glycol mono-n-butyl ether acetate;
Ethylene glycol monoalkyl ether propionates such as ethylene glycol monomethyl ether propionate, ethylene glycol monoethyl ether propionate, ethylene glycol mono-n-propyl ether propionate, ethylene glycol mono-n-butyl ether propionate;
Diethylene glycol alkyl ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether;
Propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether;
Dipropylene glycol alkyl ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol methyl ethyl ether;
Propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-n-butyl ether acetate;
Propylene glycol monoalkyl ether propionate such as propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether propionate, propylene glycol mono-n-propyl ether propionate, propylene glycol mono-n-butyl ether propionate;
Aromatic hydrocarbons such as toluene and xylene;
Ketones such as methyl ethyl ketone, 2-pentanone, 3-pentanone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone;
Methyl 2-methoxypropionate, ethyl 2-methoxypropionate, n-propyl 2-methoxypropionate, n-butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, 2-ethoxypropion N-propyl acid, n-butyl 2-ethoxypropionate, methyl 2-n-propoxypropionate, ethyl 2-n-propoxypropionate, n-propyl 2-n-propoxypropionate, 2-n-propoxypropionic acid n-butyl, methyl 2-n-butoxypropionate, ethyl 2-n-butoxypropionate, n-propyl 2-n-butoxypropionate, n-butyl 2-n-butoxypropionate, methyl 3-methoxypropionate , Ethyl 3-methoxypropionate, 3-methoxy N-propyl propionate, n-butyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, n-propyl 3-ethoxypropionate, n-butyl 3-ethoxypropionate, 3-n -Methyl propoxypropionate, ethyl 3-n-propoxypropionate, n-propyl 3-n-propoxypropionate, n-butyl 3-n-propoxypropionate, methyl 3-n-butoxypropionate, 3-n- Alkyl alkoxypropionates such as ethyl butoxypropionate, n-propyl 3-n-butoxypropionate, n-butyl 3-n-butoxypropionate,
Methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl hydroxyacetate, ethyl hydroxyacetate, n-propyl hydroxyacetate, n-butyl hydroxyacetate, 4-methoxybutyl acetate, 3-methoxybutyl acetate, acetic acid 2 -Methoxybutyl, 3-ethoxybutyl acetate, 3-proxybutyl acetate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, methyl 2-hydroxy-2-methylpropionate, 2-hydroxy-2-methyl Ethyl propionate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, n-propyl 3-hydroxypropionate, n-butyl 3-hydroxypropionate, methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, Ethoxy methoxyacetate, n-propyl methoxyacetate Pill, n-butyl methoxyacetate, methyl ethoxy acetate, ethyl ethoxy acetate, n-propyl ethoxy acetate, n-butyl ethoxy acetate, methyl n-propoxyacetate, ethyl n-propoxyacetate, n-propoxyacetate n-propyl, n- Other esters such as n-butyl propoxyacetate, methyl n-butoxyacetate, ethyl n-butoxyacetate, n-butoxyacetate, n-butyloxybutoxyacetate and the like can be mentioned.

Of these solvents, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, alkyl alkoxypropionate, acetate, and the like are preferable.
The said solvent can be used individually or in mixture of 2 or more types.
In addition, the radical polymerization initiator is not particularly limited. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2 , 2′-azobis- (4-methoxy-2,4-dimethylvaleronitrile), 4,4′-azobis (4-cyanovaleric acid), dimethyl-2,2′-azobis (2-methylpropionate), Azo compounds such as 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile); benzoyl peroxide, lauroyl peroxide, t-butylperoxypivalate, 1,1-bis (t-butylperoxy) cyclohexane, etc. And organic peroxides such as hydrogen peroxide.

Moreover, when using a peroxide as a radical polymerization initiator, it is good also as a redox type initiator using it together with a reducing agent.
These radical polymerization initiators can be used alone or in admixture of two or more.
The copolymer [α] thus obtained may be used as it is in the production of the [A] polymer, or once separated from the solution and used in the production of the [A] polymer.
The polystyrene equivalent weight average molecular weight (hereinafter referred to as “Mw”) of the copolymer [α] by gel permeation chromatography (GPC) is preferably 2,000 to 100,000, more preferably 5,000 to 50, 000. In this case, if the Mw is less than 2,000, there is a risk that the alkali developability, the remaining film ratio, etc. of the resulting film may be reduced, and the pattern shape, heat resistance, etc. may be impaired. If it exceeds 1, the resolution may be reduced, or the pattern shape may be impaired.

  The [A] polymer in the present invention is obtained by reacting the unsaturated isocyanate compound (1) with the copolymer [α].

As unsaturated isocyanate compound (1), for example,
2- (2-isocyanatoethoxy) ethyl acrylate,
2- [2- (2-isocyanatoethoxy) ethoxy] ethyl acrylate,
2- {2- [2- (2-isocyanatoethoxy) ethoxy] ethoxy} ethyl acrylate, 2- (2-isocyanatopropoxy) ethyl acrylate,
Acrylic acid derivatives such as 2- [2- (2-isocyanatopropoxy) propoxy] ethyl acrylate;
2- (2-isocyanatoethoxy) ethyl methacrylate,
2- [2- (2-isocyanatoethoxy) ethoxy] ethyl methacrylate,
2- {2- [2- (2-isocyanatoethoxy) ethoxy] ethoxy} ethyl methacrylate,
2- (2-isocyanatopropoxy) ethyl methacrylate,
And methacrylic acid derivatives such as 2- [2- (2-isocyanatopropoxy) propoxy] ethyl methacrylate.

Moreover, as a commercial item of 2- (2-isocyanatoethoxy) ethyl methacrylate, Karenz MOI-EG (made by Showa Denko KK) can be mentioned by a brand name.
Of these unsaturated isocyanate compounds (1), 2- (2-isocyanatoethoxy) ethyl acrylate, 2- (2-isocyanatoethoxy) ethyl methacrylate, and the like from the point of reactivity with the copolymer [α]. Is preferred.
[A] In the polymer, the unsaturated isocyanate compound (1) can be used alone or in admixture of two or more.

In the present invention, if necessary, the reaction between the copolymer [α] and the unsaturated isocyanate compound (1) may be carried out by using a catalyst such as di-n-butyltin (IV) dilaurate, p-methoxyphenol, etc. The unsaturated isocyanate compound (1) can be added dropwise to the copolymer [α] solution containing the polymerization inhibitor at room temperature or while stirring.
[A] The amount of unsaturated isocyanate compound (1) used in producing the polymer is (a2) in copolymer [α] with respect to the unsaturated compound containing one or more hydroxyl groups in one molecule. The content is preferably 0.1 to 95 mol%, more preferably 1.0 to 80 mol%, and particularly preferably 5.0 to 75 mol%. In this case, if the amount of the unsaturated isocyanate compound (1) used is less than 0.1 mol%, the effects on the sensitivity, heat resistance and elastic properties are small, whereas if it exceeds 95 mol%, unreacted unsaturated The isocyanate compound (1) remains, and the storage stability of the resulting polymer solution and radiation-sensitive resin composition tends to decrease.

  [A] The polymer has a carboxyl group and / or a carboxylic acid anhydride group and a polymerizable unsaturated bond, has an appropriate solubility in an alkali developer, and uses a special curing agent in combination. Can be easily cured by exposure and heating, and [A] the radiation-sensitive resin composition containing the polymer has a predetermined shape without developing residue and film loss during development. The spacer can be easily formed.

Radiation-sensitive resin composition The radiation-sensitive resin composition of the present invention contains [A] a polymer, [B] a polymerizable unsaturated compound, and [C] a radiation-sensitive polymerization initiator.
In the present invention, as the polymer component, other polymers can be used in combination with the [A] polymer (hereinafter, the [A] polymer and other polymers are collectively referred to as “[A] Called "union").
Although it does not specifically limit as said other polymer, For example, at least 1 sort (s) chosen from the group of said (a1) unsaturated carboxylic acid type compound, and said (a2) 1 or more in 1 molecule A copolymer with at least one selected from the group consisting of an unsaturated compound containing a hydroxyl group and (a3) another unsaturated compound is preferred.

In the present invention, when the [A] polymer and another polymer are used in combination, the ratio of the [A] polymer used is preferably 50 to 100% by weight, more preferably based on the total of both polymers. 80 to 100% by weight. In this case, if the use ratio is less than 50% by weight, sufficient effects for improving sensitivity, heat resistance and elastic characteristics cannot be obtained.

-[B] polymerizable unsaturated compound-
[B] The polymerizable unsaturated compound comprises an unsaturated compound that is polymerized by exposure to radiation in the presence of a radiation-sensitive polymerization initiator.
Such a [B] polymerizable unsaturated compound is not particularly limited. For example, a monofunctional, bifunctional, or trifunctional or higher (meth) acrylic acid ester has good copolymerizability. From the viewpoint of improving the strength of the obtained spacer.

  Examples of the monofunctional (meth) acrylic acid ester include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, diethylene glycol monoethyl ether acrylate, diethylene glycol monoethyl ether methacrylate, isobornyl acrylate, isobornyl methacrylate, 3- Examples include methoxybutyl acrylate, 3-methoxybutyl methacrylate, (2-acryloyloxyethyl) (2-hydroxypropyl) phthalate, (2-methacryloyloxyethyl) (2-hydroxypropyl) phthalate, and ω-carboxypolycaprolactone monoacrylate. be able to. As a commercial product, for example, Aronix M-101, M-111, M-114, M-5300 (above, manufactured by Toa Gosei Co., Ltd.); KAYARAD TC-110S, TC-120S ( As mentioned above, Nippon Kayaku Co., Ltd.); Biscoat 158, 2311 (above, Osaka Organic Chemical Industry Co., Ltd.) and the like can be mentioned.

  Examples of the bifunctional (meth) acrylic acid ester include ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, 1,6- Examples include hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol diacrylate, 1,9-nonanediol dimethacrylate, bisphenoxyethanol full orange acrylate, and bisphenoxyethanol full orange methacrylate. As commercial products, for example, Aronix M-210, M-240, M-6200 (above, manufactured by Toa Gosei Co., Ltd.), KAYARAD HDDA, HX-220, R-604 (above, Nippon Kayaku Co., Ltd.), Biscoat 260, 312 and 335HP (Osaka Organic Chemical Co., Ltd.), Light Acrylate 1,9-NDA (Kyoeisha Co., Ltd.) and the like.

  Furthermore, as the trifunctional or higher functional (meth) acrylic acid ester, for example, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, Dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, tri (2-acryloyloxyethyl) phosphate, tri (2-methacryloyloxyethyl) phosphate, and more than 9 functional groups As (meth) acrylic acid esters, linear alkylene groups and alicyclic structures And a compound having two or more isocyanate groups and a compound having one or more hydroxyl groups in the molecule and having three, four or five acryloyloxy groups and / or methacryloyloxy groups The polyfunctional urethane acrylate type compound etc. which are obtained by making it react with can be mentioned.

  Commercially available products of trifunctional or higher functional (meth) acrylic acid esters are trade names, for example, Aronix M-309, M-400, M-405, M-450, M-7100, M- 8030, M-8060, TO-1450 (above, manufactured by Toagosei Co., Ltd.), KAYARAD TMPTA, DPHA, DPCA-20, DPCA-30, DPCA-30, DPCA-60, DPCA-120 (above, Nippon Kayaku Co., Ltd.), Biscoat 295, 300, 360, GPT, 3PA, 400 (above, Osaka Organic Chemical Industry Co., Ltd.) and commercial products containing polyfunctional urethane acrylate compounds Examples of the products include New Frontier R-1150 (Daiichi Kogyo Seiyaku Co., Ltd.), KAYARAD DPHA-40H (Nippon Kayaku Co., Ltd.), and the like. wear.

Among these monofunctional, bifunctional, or trifunctional or higher (meth) acrylic acid esters, trifunctional or higher functional (meth) acrylic acid esters are more preferable, and in particular, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol. Tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, and commercial products containing polyfunctional urethane acrylate compounds are preferred.
The monofunctional, bifunctional, or trifunctional or higher (meth) acrylic acid esters can be used alone or in admixture of two or more.
In the radiation-sensitive resin composition of the present invention, the amount of the [B] polymerizable unsaturated compound used is preferably 40 to 250 parts by weight, more preferably 60, based on 100 parts by weight of the [A] alkali-soluble polymer. -180 parts by weight. In this case, if the amount of the [B] polymerizable unsaturated compound used is less than 40 parts by weight, there is a risk of developing residue during development, whereas if it exceeds 250 parts by weight, the adhesion of the resulting spacer tends to decrease. There is.

-[C] Radiation sensitive polymerization initiator-
[C] Radiation sensitive polymerization initiator generates [B] active species capable of initiating polymerization of polymerizable unsaturated compounds upon exposure to radiation such as visible light, ultraviolet light, far ultraviolet light, charged particle beam, and X-ray. It consists of the component to do.
Examples of such [C] radiation sensitive polymerization initiators include O-acyloxime compounds, acetophenone compounds, biimidazole compounds, benzoin compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, Examples include xanthone compounds, phosphine compounds, triazine compounds, and the like.

As the O-acyloxime compound, 9. H. A carbazole-based O-acyloxime polymerization initiator is preferred. For example, 1- [9-ethyl-6-benzoyl-9. H. -Carbazol-3-yl] -nonane-1,2-nonane-2-oxime-O-acetate,
1- [9-Ethyl-6-benzoyl-9. H. -Carbazol-3-yl] -pentane-1,2-pentane-2-oxime-O-acetate,
1- [9-Ethyl-6-benzoyl-9. H. -Carbazol-3-yl] -octane-1-one oxime-O-acetate,
Ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-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)
1- [9-Ethyl-6- (1,3,5-trimethylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-benzoate,
1- [9-Butyl-6- (2-ethylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-benzoate,
1- [9-Ethyl-6- (2-methyl-4-tetrahydropyranylmethoxybenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate,
1- [9-Ethyl-6- (2-methyl-4-tetrahydrofuranylmethoxybenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate and the like.

  Among these O-acyloxime compounds, in particular, ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-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) is preferred.

The O-acyloxime compounds can be used alone or in admixture of two or more. In the present invention, the use of an O-acyloxime compound makes it possible to obtain a spacer having sufficient sensitivity and adhesion even with an exposure amount of 1000 J / m ² or less.

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

  Examples of the α-hydroxyketone compound include 1-phenyl-2-hydroxy-2-methylpropan-1-one, 1- (4-i-propylphenyl) -2-hydroxy-2-methylpropane-1 -One, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenylketone and the like. Examples of the α-aminoketone compound include 2 -Methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-dimethylamino- 2- (4-Methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one and the like Door can be. Examples of compounds other than these include 2,2-dimethoxyacetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, and the like.

Among these acetophenone compounds, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-dimethylamino-2- (4-methyl-benzyl) -1- ( 4-Morpholin-4-yl-phenyl) -butan-1-one is preferred.
In the present invention, the sensitivity, spacer shape and compressive strength can be further improved by using an acetophenone compound in combination.

  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-bromophenyl) -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'-biimidazole, 2,2 '-Bis (2-bromophenyl)- , 4 ′, 5,5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (2,4-dibromophenyl) -4,4 ′, 5,5′-tetraphenyl-1, 2'-biimidazole, 2,2'-bis (2,4,6-tribromophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole and the like can be mentioned. .

  Among these biimidazole compounds, 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′-biimidazole and the like are preferable, and in particular, 2,2′-bis (2,4-dichlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2 ′. -Biimidazole is preferred.

In the present invention, it is possible to further improve sensitivity, resolution and adhesion by using a biimidazole compound in combination.
When a biimidazole compound is used in combination, an aliphatic or aromatic compound having a dialkylamino group (hereinafter referred to as “amino sensitizer”) may be added to sensitize it. it can.

Examples of amino sensitizers include N-methyldiethanolamine, 4,4′-bis (dimethylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, ethyl p-dimethylaminobenzoate, p-dimethylamino. Examples include i-amyl benzoate.
Of these amino sensitizers, 4,4′-bis (diethylamino) benzophenone is particularly preferable.
The amino sensitizers can be used alone or in admixture of two or more.

  Further, when a biimidazole compound and an amino sensitizer are used in combination, a thiol compound can be added as a hydrogen donor compound. The biimidazole compound is sensitized and cleaved by the amino sensitizer to generate an imidazole radical, but as it is, high polymerization initiating ability is not expressed, and the resulting spacer has an unfavorable shape such as a reverse taper shape. In many cases. However, by adding a thiol compound to a system in which a biimidazole compound and an amino sensitizer coexist, hydrogen radicals are donated from the thiol compound to the imidazole radical, so that the imidazole radical is neutral imidazole. In addition, a component having a sulfur radical having a high polymerization initiating ability is generated, whereby the spacer can have a more preferable forward taper shape.

Examples of the thiol compound include aromatics such as 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole, 2-mercapto-5-methoxybenzothiazole, 2-mercapto-5-methoxybenzimidazole. Compounds: aliphatic monothiols such as 3-mercaptopropionic acid, methyl 3-mercaptopropionate, ethyl 3-mercaptopropionate, octyl 3-mercaptopropionate; 3,6-dioxa-1,8-octanedithiol, Bifunctional or higher aliphatic thiols such as pentaerythritol tetra (mercaptoacetate) and pentaerythritol tetra (3-mercaptopropionate) can be exemplified.
Of these thiol compounds, 2-mercaptobenzothiazole is particularly preferable.

Further, when the biimidazole compound and the amino sensitizer are used in combination, the addition amount of the amino sensitizer is preferably 0.1 to 150 parts by weight with respect to 100 parts by weight of the biimidazole compound. Preferably it is 1-125 weight part. In this case, if the addition amount of the amino sensitizer is less than 0.1 parts by weight, the effect of improving the sensitivity, resolution and adhesion tends to decrease, whereas if it exceeds 150 parts by weight, the shape of the spacer obtained is There is a tendency to be damaged.
In addition, when a biimidazole compound and an amino sensitizer are used in combination, the addition amount of the thiol compound is preferably 0.1 to 100 parts by weight, more preferably 100 parts by weight of the biimidazole compound. 1 to 75 parts by weight. In this case, if the added amount of the thiol compound is less than 0.1 parts by weight, the effect of improving the shape of the spacer tends to be reduced, or the film tends to be reduced. There is a tendency that the shape of is damaged.

Said radiation sensitive polymerization initiator can be used individually or in mixture of 2 or more types.
In the radiation-sensitive resin composition of the present invention, the use ratio of [C] radiation-sensitive polymerization initiator is preferably 1 to 50 parts by weight with respect to 100 parts by weight of [A] alkali-soluble polymer. Preferably it is 3-40 weight part.

-Additives-
In the radiation-sensitive resin composition of the present invention, a surfactant, an adhesion assistant, a storage stabilizer, a heat resistance, in addition to the above components, if necessary, within a range that does not impair the intended effect of the present invention. Additives such as property improvers can also be blended.
The said surfactant is a component which has the effect | action which improves coating property, and a fluorine-type surfactant and a silicone type surfactant are preferable.

  The fluorine-based surfactant is preferably a compound having a fluoroalkyl group or a fluoroalkylene group at at least one of the terminal, main chain and side chain, and specific examples thereof include 1,1,2,2- Tetrafluorooctyl (1,1,2,2-tetrafluoro-n-propyl) ether, 1,1,2,2-tetrafluoro-n-octyl (n-hexyl) ether, octaethylene glycol di (1,1 , 2,2-tetrafluoro-n-butyl) ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoro-n-pentyl) ether, octapropylene glycol di (1,1,2, 2-tetrafluoro-n-butyl) ether, hexapropylene glycol di (1,1,2,2,3,3-hexafluoro-n- Nethyl) ether, 1,1,2,2,3,3-hexafluoro-n-decane, 1,1,2,2,8,8,9,9,10,10-decafluoro-n-dodecane, Sodium perfluoro-n-dodecyl sulfonate, sodium fluoroalkylbenzene sulfonate, sodium fluoroalkyl phosphonate, sodium fluoroalkyl carboxylate, fluoroalkyl polyoxyethylene ether, diglycerin tetrakis (fluoroalkyl polyoxyethylene ether), fluoroalkyl Ammonium iodide, fluoroalkyl betaine, fluoroalkyl polyoxyethylene ether, perfluoroalkyl polyoxyethanol, perfluoroalkyl alkoxylate, fluorine alkyl ester and the like can be mentioned.

  Moreover, as a commercial item of a fluorine-type surfactant, it is a brand name, for example, BM-1000, the same -1100 (above, the product made from BM CHEMIE), MegaFuck F142D, the same F172, the same F173, the same F183, the same F178. F191, F471, F476 (above, manufactured by Dainippon Ink & Chemicals, Inc.), Florard FC 170C, FC-171, FC-430, FC-431 (above, manufactured by Sumitomo 3M Limited) ), Surflon S-112, S-113, S-131, S-141, S-145, S-382, SC-101, SC-102, SC-103, SC-103 104, SC-105, SC-106 (above, manufactured by Asahi Glass Co., Ltd.), F-top EF301, EF303, EF352 (above, manufactured by Shin-Akita Kasei Co., Ltd.), lid Agent FT-100, FT-110, FT-140A, FT-150, FT-250, FT-251, FTX-251, FTX-218, FT-300, FT-310, FT-400S (above, manufactured by Neos Co., Ltd.) and the like.

  Examples of the silicone-based surfactant include commercially available products, such as Toray Silicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, and SH-193. , SZ-6032, SF-8428, DC-57, DC-190 (above, manufactured by Toray Dow Corning Silicone Co., Ltd.), TSF-4440, -4300, -4445, -4446 -4460, -4442 (above, manufactured by GE Toshiba Silicone Co., Ltd.), and the like.

  Furthermore, as surfactants other than the above, for example, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene n-octylphenyl ether, polyoxy Polyoxyethylene aryl ethers such as ethylene n-nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate, and commercial products, For example, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 57, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.).

The surfactants can be used alone or in admixture of two or more.
The compounding amount of the surfactant is preferably 5 parts by weight or less, more preferably 2 parts by weight or less, with respect to 100 parts by weight of the [A] alkali-soluble polymer. In this case, when the compounding amount of the surfactant exceeds 5 parts by weight, there is a tendency that film roughening is likely to occur during coating.
The adhesion assistant is a component having an effect of further improving the adhesion between the spacer and the substrate, and a functional silane coupling agent is preferable.

Examples of the functional silane coupling agent include compounds having a reactive functional group such as a carboxyl group, a methacryloyl group, a vinyl group, an isocyanate group, and an epoxy group, and more specifically, trimethoxysilyl. Benzoic acid, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ) Ethyltrimethoxysilane and the like.
These adhesion assistants can be used alone or in admixture of two or more.
The blending amount of the adhesion assistant is preferably 20 parts by weight or less, more preferably 10 parts by weight or less with respect to 100 parts by weight of the [A] alkali-soluble polymer. In this case, when the blending amount of the adhesion assistant exceeds 20 parts by weight, there is a tendency that a development residue is likely to occur.

Examples of the storage stabilizer include sulfur, quinones, hydroquinones, polyoxy compounds, amines, nitronitroso compounds, and more specifically, 4-methoxyphenol, N-nitroso-N-phenyl. Examples include hydroxylamine aluminum.
These storage stabilizers can be used alone or in admixture of two or more.
The amount of the storage stabilizer is preferably 3 parts by weight or less, more preferably 0.001 to 0.5 parts by weight, based on 100 parts by weight of the [A] alkali-soluble polymer. In this case, if the amount of the storage stabilizer exceeds 3 parts by weight, the sensitivity may decrease and the pattern shape may be impaired.

Examples of the heat resistance improver include N- (alkoxymethyl) glycoluril compounds and N- (alkoxymethyl) melamine compounds.
Examples of the N- (alkoxymethyl) glycoluril compound 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- (alkoxymethyl) glycoluril compounds, N, N, N, N-tetra (methoxymethyl) glycoluril is particularly preferred.

Examples of the N- (alkoxymethyl) melamine compound include N, N, N, N, N, N-hexa (methoxymethyl) melamine, N, N, N, N, N, N-hexa (ethoxy). Methyl) melamine, N, N, N, N, N, N-hexa (n-propoxymethyl) melamine, N, N, N, N, N, N-hexa (i-propoxymethyl) melamine, N, N, Examples thereof include N, N, N, N-hexa (n-butoxymethyl) melamine, N, N, N, N, N, N-hexa (t-butoxymethyl) melamine and the like.
Among these N- (alkoxymethyl) melamine compounds, N, N, N, N, N, N-hexa (methoxymethyl) melamine is particularly preferable, and a commercial product thereof is, for example, Nicalac N- 2702, MW-30M (manufactured by Sanwa Chemical Co., Ltd.) and the like.
The heat resistance improvers can be used alone or in admixture of two or more.

The blending amount of the heat resistance improver is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, with respect to 100 parts by weight of the [A] alkali-soluble polymer. In this case, when the compounding amount of the heat resistance improver exceeds 30 parts by weight, the storage stability of the radiation-sensitive resin composition tends to decrease.
The radiation-sensitive resin composition of the present invention is preferably used as a composition solution dissolved in an appropriate solvent.

As the solvent, each component constituting the radiation-sensitive resin composition is uniformly dissolved, does not react with each component, and has a suitable volatility, but the solubility of each component, each component and Alcohols, ethylene glycol monoalkyl ether acetate, diethylene glycol monoalkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, dipropylene glycol alkyl ether, alkoxypropionic acid Alkyl, acetate ester and the like are preferable, and in particular, benzyl alcohol, 2-phenylethanol, 3-phenyl-1-propanol, ethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ester. Ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, dipropylene glycol dimethyl ether, 3-methoxybutyl acetate, 2-methoxyethyl acetate and the like are preferable.
The said solvent can be used individually or in mixture of 2 or more types.

In the present invention, a high boiling point solvent may be used in combination with the solvent.
Examples of the high boiling point solvent include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and benzylethyl ether. , Di-n-hexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, Examples thereof include ethylene carbonate, propylene carbonate, and ethylene glycol monophenyl ether acetate.

These high boiling point solvents can be used alone or in admixture of two or more.
In addition, the composition solution prepared as described above can be filtered for use with a Millipore filter or the like having a pore diameter of about 0.5 μm.
Especially the radiation sensitive resin composition of this invention can be used very suitably for formation of the spacer for liquid crystal display elements.

Method of forming spacers Next, a method of forming a spacer of the present invention will be described with reference to radiation-sensitive resin composition of the present invention.

The formation of the spacer of the present invention includes at least the following steps in the order described below.
(A) forming a film of the radiation sensitive resin composition of the present invention on a substrate;
(B) exposing at least a part of the coating;
(C) a step of developing the coated film after exposure, and (d) a step of heating the coated film after development.

  Hereinafter, each of these steps will be described sequentially.

-(I) Process-
A transparent conductive film is formed on one surface of a transparent substrate, and a radiation-sensitive resin composition is applied onto the transparent conductive film, preferably as a composition solution, and then the coated surface is heated (prebaked) to form a coating film. Form.
Examples of the transparent substrate used for forming the spacer include a glass substrate and a resin substrate. More specifically, glass substrates such as soda lime glass and non-alkali glass; polyethylene terephthalate, polybutylene terephthalate, Examples thereof include a resin substrate made of a plastic such as polyethersulfone, polycarbonate, and polyimide.

Examples of the transparent conductive film provided on one surface of the transparent substrate include a NESA film (registered trademark of US PPG) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ), etc. Can be used.
As a method for applying the composition solution, for example, (1) a coating method and (2) a dry film method can be used as a method for forming a film of the photosensitive resin composition of the present invention.
As a coating method of the composition solution, for example, an appropriate method such as a spray method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, or an ink jet coating method can be employed. In particular, a spin coating method and a slit die coating method are preferable.

Further, when the film of the photosensitive resin composition of the present invention is formed, (2) when the dry film method is adopted, the dry film is formed on the base film, preferably a flexible base film. And a photosensitive layer made of the photosensitive resin composition (hereinafter referred to as “photosensitive dry film”).
The photosensitive dry film can be formed by laminating a photosensitive layer on the base film by applying the photosensitive resin composition of the present invention, preferably as a liquid composition, and then drying. As a base film of the photosensitive dry film, for example, a synthetic resin film such as polyethylene terephthalate (PET), polyethylene, polypropylene, polycarbonate, polyvinyl chloride, or the like can be used. The thickness of the base film is suitably in the range of 15 to 125 μm. The thickness of the obtained photosensitive layer is preferably about 1 to 30 μm.

Moreover, the photosensitive dry film can also be preserve | saved by laminating | stacking a cover film on the photosensitive layer at the time of unused. This cover film needs to have an appropriate releasability so that it does not peel off when not in use and can be easily peeled off when in use. As a cover film satisfying such conditions, for example, a film based on a silicone-based release agent or a baking film can be used on the surface of a synthetic resin film such as a PET film, a polypropylene film, a polyethylene film, or a polyvinyl chloride film. . A thickness of about 25 μm is usually sufficient for the cover film.
Moreover, although the conditions of prebaking differ also with the kind of each component, a mixture ratio, etc., it is normally about 1 to 15 minutes at 70-120 degreeC.

-(B) Process-
Next, at least a part of the formed film is exposed. In this case, when exposing a part of the film, the exposure is usually performed through a photomask having a predetermined pattern.
As the radiation used for the exposure, for example, visible light, ultraviolet light, far ultraviolet light, electron beam, X-ray and the like can be used. However, radiation having a wavelength in the range of 190 to 450 nm is preferable, and particularly radiation containing 365 nm ultraviolet light. Is preferred.
The exposure dose is usually 100 to 10,000 J / m ² , preferably 500 to 500, as a value measured by an illuminometer (OAI model 356, manufactured by OAI Optical Associates Inc.) at a wavelength of 365 nm of the radiation to be exposed. 1,500 J / m ² .

-(C) Process-
Subsequently, the exposed film is developed to remove unnecessary portions and form a predetermined pattern.
As the developer used for development, an alkali developer is preferable, and examples thereof include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia; ethylamine, n- Aliphatic primary amines such as propylamine; Aliphatic secondary amines such as diethylamine and di-n-propylamine; Aliphatic tertiary amines such as trimethylamine, methyldiethylamine, dimethylethylamine and triethylamine; pyrrole, piperidine and N-methyl Alicyclic tertiary amines such as piperidine, N-methylpyrrolidine, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo [4.3.0] -5-nonene; pyridine , Aromatic tertiary amines such as collidine, lutidine and quinoline; Examples include aqueous solutions of alkaline compounds such as alkanolamines such as methylamine, methyldiethanolamine and triethanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide.

In addition, an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant can be added to the aqueous solution of the alkaline compound.
As a developing method, any of a liquid filling method, a dipping method, a shower method and the like may be used, and the developing time is usually about 10 to 180 seconds.
After development, for example, after washing with running water for 30 to 90 seconds, a desired pattern is formed by, for example, air drying with compressed air or compressed nitrogen.

-(2) Process-
Next, the obtained pattern is heated at a predetermined temperature, for example, 100 to 230 ° C., for a predetermined time, for example, 5 to 30 minutes on the hot plate, for 30 to 180 minutes in the oven, by a heating device such as a hot plate or an oven. A predetermined spacer can be obtained by heating (post-baking).
The conventional radiation-sensitive resin composition used for the formation of the spacer cannot obtain sufficient performance unless the heat treatment is performed at a temperature of about 180 to 200 ° C. or higher. In the radiation-sensitive resin composition, the heating temperature can be made lower than before, and as a result, without causing yellowing or deformation of the resin substrate, compressive strength, rubbing resistance during liquid crystal alignment, adhesion to the transparent substrate It is possible to form a spacer excellent in various properties such as properties.

Liquid crystal display element The liquid crystal display element of the present invention comprises the spacer of the present invention formed as described above.
The structure of the liquid crystal element of the present invention is not particularly limited. For example, as shown in FIG. 1, a color filter layer and a spacer are formed on a transparent substrate, and the liquid crystal element 2 is disposed via the liquid crystal layer. A structure having two alignment films, opposing transparent electrodes, opposing transparent substrates, and the like can be given. Moreover, as shown in FIG. 1, you may form a protective film on a polarizing plate or a color filter layer as needed.
In addition, as shown in FIG. 2, a color filter layer and a spacer are formed on a transparent substrate, and are opposed to a thin film transistor (TFT) array through an alignment film and a liquid crystal layer, whereby a TN-TFT type liquid crystal display. It can also be an element. Also in this case, a protective film may be formed on the polarizing plate or the color filter layer as necessary.

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. Here, parts and% are based on weight.

Synthesis example 1
A flask equipped with a condenser and a stirrer was charged with 5 parts of 2,2′-azobisisobutyronitrile and 250 parts of 3-methoxybutyl acetate, followed by 18 parts of methacrylic acid and tricyclomethacrylate [5.2. 1.0 ^2,6 ] 25 parts of decan-8-yl, 5 parts of styrene, 30 parts of methacrylic acid 2-hydroxyethyl ester, 22 parts of benzyl methacrylate, and after purging with nitrogen, the solution was stirred gently. Was increased to 80 ° C. and polymerization was carried out while maintaining this temperature for 5 hours to obtain a copolymer [α-1] solution having a solid content concentration of 28.8%.

  For the obtained copolymer [α-1], Mw was measured using GPC (Gel Permeation Chromatography) GPC-101 (trade name, manufactured by Showa Denko KK) and found to be 13,000. It was.

Synthesis example 2
To 100 parts of the copolymer [α-1] solution, 15 parts of 2- (2-isocyanatoethoxy) ethyl methacrylate (trade name Karenz MOI-EG, manufactured by Showa Denko Co., Ltd.), 4-methoxyphenol 0.1 After adding a part, it was made to react by stirring at 40 degreeC for 1 hour, and also at 60 degreeC for 2 hours. The progress of the reaction of the isocyanate group derived from 2- (2-isocyanatoethoxy) ethyl methacrylate and the hydroxyl group of the copolymer [α-1] was confirmed by IR (infrared absorption) spectrum. In the IR spectrum of the polymer solution [α-1] after 1 hour of reaction and the solution after reaction at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours, respectively, the 2- (2-isocyanatoethoxy) ethyl methacrylate group It was confirmed that the peak in the vicinity of 2270 cm ⁻¹ was reduced. An [A] polymer solution having a solid content concentration of 31.8% was obtained. Let this [A] polymer be a polymer (A-1).

Synthesis example 3
After adding 15 parts of 2- (2-isocyanatoethoxy) ethyl acrylate and 0.1 part of 4-methoxyphenol to 100 parts of the copolymer [α-1] solution, 1 hour at 40 ° C., and further 60 ° C. For 2 hours with stirring. The progress of the reaction between the isocyanate group derived from 2- (2-isocyanatoethoxy) ethyl acrylate and the hydroxyl group of the copolymer [α-1] was confirmed by IR (infrared absorption) spectrum as in Synthesis Example 2. A [A] polymer solution having a solid concentration of 31.5% was obtained. Let this [A] polymer be a polymer (A-2).

Synthesis example 4
After adding 19 parts of 2- [2- (2-isocyanatoethoxy) ethoxy] ethyl methacrylate and 0.1 part of 4-methoxyphenol to 100 parts of the copolymer [α-1] solution, 1 part at 40 ° C. The mixture was further stirred for 2 hours at 60 ° C. for reaction. The progress of the reaction of the isocyanate group derived from 2- [2- (2-isocyanatoethoxy) ethoxy] ethyl methacrylate and the hydroxyl group of the copolymer [α-1] is determined by IR (infrared absorption) spectrum as in Synthesis Example 2. confirmed. A [A] polymer solution having a solid content concentration of 32.5% was obtained. Let this [A] polymer be a polymer (A-3).

Synthesis example 5
After adding 12 parts of 3-methacryloyloxyphenyl isocyanate (trade name Karenz MOI-PH, Showa Denko KK) and 0.1 part of 4-methoxyphenol to the copolymer [α-1] solution, The reaction was stirred at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours. The progress of the reaction between the isocyanate group derived from 3-methacryloyloxyphenyl isocyanate and the hydroxyl group of the copolymer [α-1] was confirmed by IR (infrared absorption) spectrum as in Synthesis Example 2. A [A] polymer solution having a solid concentration of 31.0% was obtained. This [A] polymer is referred to as a polymer (A-4).

Synthesis Example 6
After adding 12 parts of methacryloyloxyethyl isocyanate (trade name Karenz MOI, manufactured by Showa Denko KK) and 0.1 part of 4-methoxyphenol to the copolymer [α-1] solution, 1 solution at 40 ° C. The mixture was further stirred for 2 hours at 60 ° C. for reaction. The progress of the reaction of the isocyanate group derived from 3-methacryloyloxyethyl isocyanate and the hydroxyl group of the copolymer [α-1] was confirmed by IR (infrared absorption) spectrum as in Synthesis Example 2. An [A] polymer solution having a solid content concentration of 31.2% was obtained. Let this [A] polymer be a polymer (A-5).

Synthesis example 7
A flask equipped with a condenser and a stirrer was charged with 7 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 250 parts of diethylene glycol methyl ethyl ether, followed by 18 parts of methacrylic acid, tricyclomethacrylate [ 5.2.1.0 ^2,6 ] Decan-8-yl 25 parts, styrene 5 parts, butadiene 5 parts, glycidyl methacrylate 10 parts, methacrylic acid 2-hydroxyethyl ester 25 parts, tetrahydrofuran-2-yl methacrylate After charging 12 parts and substituting with nitrogen, the temperature of the solution was raised to 70 ° C. while gently stirring, and polymerization was carried out while maintaining this temperature for 5 hours, whereby a solid content concentration of 28.3% was obtained. A combined [α-2] solution was obtained.

  For the obtained copolymer [α-2], Mw was measured using GPC (Gel Permeation Chromatography) GPC-101 (trade name, manufactured by Showa Denko KK) and found to be 9,000. It was.

Synthesis example 8
Next, 15 parts of 2- (2-isocyanatoethoxy) ethyl methacrylate and 0.1 part of 4-methoxyphenol were added to 100 parts of the copolymer [α-2] solution, and then at 40 ° C. for 1 hour, further 60 parts. By stirring and reacting at 2 ° C. for 2 hours, a [A] polymer solution having a solid content concentration of 31.2% was obtained. Let this [A] polymer be a polymer (A-6).

Synthesis Example 9
A flask equipped with a condenser and a stirrer was charged with 5 parts of 2,2′-azobisisobutyronitrile and 250 parts of 3-methoxybutyl acetate, followed by 18 parts of methacrylic acid and tricyclomethacrylate [5.2. 1.0 ^2,6 ] 25 parts of decan-8-yl, 5 parts of styrene, 5 parts of butadiene, 2- (6-hydroxyhexanoyloxy) ethyl methacrylate (trade name PLACEL FM1D (manufactured by Daicel Chemical Industries, Ltd.) ) After charging 25 parts and 22 parts of tetrahydrofuran-2-yl methacrylate and purging with nitrogen, the temperature of the solution was raised to 80 ° C. while gently stirring, and this temperature was maintained for 5 hours for polymerization. A copolymer [α-3] solution having a solid content concentration of 29.0% was obtained.

  For the obtained copolymer [α-3], Mw was measured using GPC (Gel Permeation Chromatography) GPC-101 (trade name, manufactured by Showa Denko KK). It was.

Synthesis Example 10
Next, 15 parts of 2- (2-isocyanatoethoxy) ethyl methacrylate and 0.1 part of 4-methoxyphenol were added to the copolymer [α-3] solution, and then at 40 ° C. for 1 hour and further at 60 ° C. Was reacted for 2 hours to obtain an [A] polymer solution having a solid content concentration of 31.0%. This [A] polymer is referred to as a polymer (A-7).

Synthesis Example 11
Next, 12 parts of methacryloyloxyethyl isocyanate and 0.1 part of 4-methoxyphenol were added to the copolymer [α-3] solution, and the mixture was stirred at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours. By reacting, an [A] polymer solution having a solid content concentration of 31.0% was obtained. Let this [A] polymer be a polymer (A-8).

Synthesis Example 12
A flask equipped with a condenser and a stirrer was charged with 3 parts of 2,2′-azobisisobutyronitrile and 200 parts of 3-methoxybutyl acetate, followed by 18 parts of methacrylic acid and tricyclomethacrylate [5.2. 1.0 ^2,6 ] 25 parts of decan-8-yl, 5 parts of styrene, 30 parts of methacrylic acid 2-hydroxyethyl ester, 22 parts of benzyl methacrylate, and after purging with nitrogen, the solution was stirred gently. The temperature was raised to 80 ° C., and this temperature was maintained for 6 hours for polymerization to obtain a copolymer [α-4] solution having a solid content concentration of 33.5%.

  For the obtained copolymer [α-4], Mw was measured using GPC (Gel Permeation Chromatography) GPC-101 (trade name, manufactured by Showa Denko KK) and found to be 30,000. It was.

Synthesis Example 13
Subsequently, 15 parts of 2- (2-isocyanatoethoxy) ethyl methacrylate (trade name Karenz MOI-EG, manufactured by Showa Denko KK), 4-methoxyphenol 0.1 was added to the copolymer [α-4] solution. After adding a part, it was made to react by stirring at 40 degreeC for 1 hour, and also at 60 degreeC for 2 hours. An [A] polymer solution having a solid content concentration of 36.0% was obtained. This [A] polymer is referred to as a polymer (A-9).

Synthesis Example 14
Subsequently, 12 parts of 3-methacryloyloxyphenyl isocyanate (trade name Karenz MOI-PH, Showa Denko KK) and 0.1 part of 4-methoxyphenol were added to the copolymer [α-4] solution. Thereafter, the reaction was carried out by stirring at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours. An [A] polymer solution having a solid content concentration of 35.0% was obtained. This [A] polymer is referred to as a polymer (A-10).

Synthesis Example 15
Subsequently, after adding 12 parts of methacryloyloxyethyl isocyanate (trade name Karenz MOI, Showa Denko KK) and 0.1 part of 4-methoxyphenol to the copolymer [α-4] solution, 40 ° C. For 1 hour, and further at 60 ° C. for 2 hours with stirring. An [A] polymer solution having a solid content concentration of 35.0% was obtained. This [A] polymer is referred to as polymer (A-11).

Example 1
Preparation of Composition Solution As component [A], 100 parts of polymer solution [A] obtained in Synthesis Example 2 as polymer (A-1) and dipentaerystol hexaacrylate (trade name) as component [B] KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.) 100 parts, [C] component, ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- ( O-acetyloxime) (trade name IRGACURE OXE02, manufactured by Ciba Specialty Chemicals Co., Ltd.) 5 parts, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1, 2′-biimidazole 5 parts, 4,4′-bis (diethylamino) benzophenone 5 parts, 2-mercaptobenzothiazole 2.5 parts, γ-glycidoxypropylto 5 parts of methoxysilane, 0.5 part of FTX-218 (trade name, manufactured by Neos Co., Ltd.) as a surfactant, 0.5 part of 4-methoxyphenol as a storage stabilizer are mixed, and the solid content concentration is 30 % Was dissolved in propylene glycol monomethyl ether acetate and then filtered through a Millipore filter having a pore size of 0.5 μm to prepare a composition solution.

  In Table 1, each component other than the polymer is as follows.

[B] Component B-1: Dipentaerystol hexaacrylate (trade name KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.)
B-2: A commercial product containing a polyfunctional urethane acrylate compound (trade name KAYARDADDHA-40H, manufactured by Nippon Kayaku Co., Ltd.)
B-3: Pentaerystol tetraacrylate (trade name Aronix M-450 (manufactured by Toa Gosei Co., Ltd.)
B-4: ω-carboxypolycaprolactone monoacrylate (trade name Aronix M-5300 (manufactured by Toa Gosei Co., Ltd.)
B-5: 1,9-nonane diacrylate (trade name: Light acrylate 1,9-NDA (manufactured by Kyoeisha)

[C] Component C-1: Ethanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime) (trade name IRGACURE OXE02, Ciba・ Specialty Chemicals
C-2: Ethanone-1- [9-ethyl-6- [2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl] -9. H. -Carbazol-3-yl] -1- (O-acetyloxime) (N-1919 manufactured by ADEKA)
C-3: 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (trade name Irgacure 907, manufactured by Ciba Specialty Chemicals)
C-4: 2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one (trade name Irgacure 379, Ciba Specialty (Chemicals)
C-5: 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole C-6: 4,4′-bis (diethylamino) benzophenone C-7: 2-mercaptobenzothiazole

[D] Component D-1: Multifunctional novolak type epoxy resin (trade name, manufactured by Japan Epoxy Resin Co., Ltd., Epicoat 152)
In Examples 2 to 14 and Comparative Examples 1 to 7, composition solutions having the compositions shown in Table 1 were prepared in the same manner as in Example 1. In Example 14 and Comparative Examples 6 to 7, composition solutions were prepared so that the solid content concentration was 50%.

Formation of Spacer In Examples 1 to 13 and Comparative Examples 1 to 5, a spacer was formed by applying to a substrate using a spinner. The details are shown below.
The composition solution was applied on a non-alkali glass substrate using a spinner, and then pre-baked on a hot plate at 100 ° C. for 3 minutes to form a film having a thickness of 3.5 μm.
Next, the obtained coating film was exposed through a photomask having a 10 μm square left pattern. Thereafter, development was performed with an aqueous solution of 0.05% by weight of potassium hydroxide at 25 ° C. for 60 seconds, followed by washing with pure water for 1 minute, and further heating in an oven at 230 ° C. for 30 minutes to form a spacer.
In Example 14 and Comparative Examples 6 to 7, spacers were formed by the dry film method. Details are shown below.

Example 14
A patterned thin film was formed and evaluated in the same manner as in Examples 1 to 13, except that a coating film was prepared from the liquid composition (S-14) of the radiation sensitive resin composition by the dry film method. Each component is shown in Table 1. The base film was peeled and removed before the exposure process. The evaluation results are shown in Table 2.
Dry film preparation and transfer were performed as follows.
On a polyethylene terephthalate (PET) film having a thickness of 38 μm, a liquid composition (S-14) of a radiation sensitive resin composition was applied using an applicator, the coating film was heated at 100 ° C. for 5 minutes, and a thickness of 4 μm. A radiation-sensitive dry film (J-1) was prepared. Next, the radiation-sensitive transfer dry film is superposed on the surface of the glass substrate so that the surface of the radiation-sensitive transfer layer is in contact with the glass substrate, and the radiation-sensitive dry film (J-1) is laminated on the glass substrate by thermocompression bonding. Transcribed to.

Comparative Example 6
In Example 14, it replaces with the liquid composition (S-14) of a radiation sensitive resin composition, and uses the liquid composition (s-6) of a radiation sensitive resin composition, It is the same as that of Example 13. After producing a radiation-sensitive dry film (J-2), a patterned thin film was formed and evaluated. Each component is shown in Table 1. The evaluation results are shown in Table 2.

Comparative Example 7
Except using the liquid composition (s-7) of a radiation sensitive resin composition, it is the same as that of the comparative example 6, and after producing a radiation sensitive dry film (J-3), a pattern thin film is formed and evaluated. did. Each component is shown in Table 1. The evaluation results are shown in Table 2.

  Next, various evaluations were performed in the following manner. The evaluation results are shown in Table 2.

(1) Sensitivity evaluation When the spacer is formed in the same manner as the formation of the spacer, the exposure amount at which the residual film ratio after post-baking (film thickness after post-baking × 100 / film thickness after exposure) is 90% or more. Was the sensitivity. When this exposure amount is 1,000 J / m ² or less, it can be said that the sensitivity is good.

(2) Evaluation of elastic recovery rate About the obtained spacer, using a micro compression tester (trade name DUH-201, manufactured by Shimadzu Corporation), a flat indenter with a diameter of 50 μm was used for both loading speed and unloading speed. A load of up to 50 mN was applied as 2.6 mN / sec, the load was held for 5 seconds, and then unloaded, and a load-deformation curve at loading and a load-deformation curve during unloading were created. At this time, as shown in FIG. 3, the deformation amount at the load of 50 mN at the time of loading was set to L1, and the deformation amount at the time of unloading was set to L2.
Elastic recovery rate (%) = L2 × 100 / L1
Table 2 shows the elastic recovery rate (%) and the deformation amount L1 (μm).
When the deformation amount L1 is 0.2 μm or more, it can be said that the flexibility is good.

(3) Evaluation of rubbing resistance AL3046 (trade name, manufactured by JSR Co., Ltd.) as a liquid crystal aligning agent was applied to a substrate on which a spacer was formed by a printing machine for applying a liquid crystal alignment film, and then dried at 180 ° C. for 1 hour. A film of a liquid crystal aligning agent having a thickness of 0.05 μm was formed.
Thereafter, the coating film was subjected to a rubbing treatment with a rubbing machine having a roll around which a polyamide cloth was wound, with a roll rotation speed of 500 rpm and a stage moving speed of 1 cm / sec. At this time, the presence or absence of pattern peeling was evaluated.

(4) Evaluation of adhesion After forming a cured film in the same manner as in the formation of the spacer except that no photomask was used, 8 of the adhesion tests of JIS K-5400 (1900) 8.5 Evaluation was performed by the cross-cut tape method of. At this time, the number of remaining grids out of 100 grids is shown in Table 2.

(5) Evaluation of heat resistance A cured film was formed in the same manner as in the formation of the spacer except that no photomask was used. After that, the film was additionally heated in an oven at 240 ° C. for 60 minutes. It was measured and evaluated by the remaining film ratio (film thickness after additional heating × 100 / film thickness before additional heating).

(6) Evaluation of storage stability The rate of change in viscosity was measured when the radiation-sensitive resin composition was left in a constant temperature layer at 40 ° C. for 1 week. Storage stability is good when the rate of increase in viscosity is less than 5%, and storage stability is poor when it is 5% or more.

It is a schematic diagram of an example for demonstrating the structure of a liquid crystal display element. It is a schematic diagram of the other example for demonstrating the structure of a liquid crystal display element. It is a figure which illustrates the load-deformation amount curve at the time of the load in evaluation of an elastic recovery factor, and a slow load.

Claims (7)

The polymer main chain is composed of a monomer containing at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, and a group represented by the following formula (1) on the polymer side chain A polymer characterized by comprising:

(In Formula (1), R ₁ is a hydrogen atom or a methyl group, R ₂ is an ethylene group or a propylene group, n is an integer of 1 to 5. “*” is a bond. Is shown.) (A1) a copolymer of at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride and (a2) an unsaturated compound containing one or more hydroxyl groups in one molecule, The polymer of Claim 1 obtained by making the compound represented by Formula (2) react.

(In the formula _(2), R 1, _{R 2} and n have the same meanings as _R 1, _{R 2} and n in each formula (1).)   [A] A radiation-sensitive resin composition comprising the polymer according to claim 1 or 2, [B] a polymerizable unsaturated compound, and [C] a radiation-sensitive polymerization initiator. The radiation sensitive resin composition of Claim 3 used for formation of the spacer for liquid crystal display elements.   The spacer for liquid crystal display elements formed from the radiation sensitive resin composition of Claim 4. A method for forming a spacer for a liquid crystal display element, comprising at least the following steps in the order described below.
(A) forming a film of the radiation sensitive resin composition according to claim 4 on a substrate;
(B) exposing at least a part of the coating;
(C) a step of developing the film after exposure, and (d) a step of heating the film after development.   A liquid crystal display device comprising the spacer according to claim 5.

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