JP2006077231A - Side chain unsaturated polymer, radiation sensitive resin composition and spacer for liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a radiation sensitive resin composition which can acquire a sufficient spacer configuration even in the exposure of not more than 1,200 J/m<SP>2</SP>with high sensitivity and high resolution and also can form a spacer for a liquid crystal display element excellent in elastic recovery, rubbing resistance, adhesiveness with a transparent substrate, heat resistance, or the like. <P>SOLUTION: The radiation sensitive resin composition comprises: a polymer which is obtained by reacting an isocyanate compound expressed by formula (1) (in formula (1), R<SP>1</SP>represents hydrogen atom or methyl group and R<SP>2</SP>represents an alkylene group) with a copolymer of (a1) an unsaturated carboxylic acid and/or an unsaturated carboxylic acid anhydride, (a2) an epoxy group-containing unsaturated compound, (a3) a hydroxyl group-containing unsaturated compound, and (a4) another unsaturated compound; a polymerizable unsaturated compound; and a radiation sensitive polymerization initiator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a novel side chain unsaturated polymer useful as a resin component of a radiation sensitive resin composition particularly suitable for forming a spacer in a liquid crystal display device, and a radiation sensitive resin containing the side chain unsaturated polymer. The present invention relates to a composition, a spacer, a formation method thereof, and a liquid crystal display element.

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 randomly distributed on a transparent substrate such as a glass substrate, so if there is a spacer in the pixel formation area, the spacer will be reflected, or the incident light will be scattered and the contrast of the liquid crystal display element will be reduced. There was a problem to do.
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) from the viewpoint of increasing the area of the liquid crystal display element and improving productivity. However, since the conventional substrate size (about 680 × 880 mm) is smaller than the mask size, it was possible to cope with the batch exposure method. However, in the case of a large substrate, the mask size is about the same as this substrate size. It is almost impossible to manufacture, 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, reduction of throughput is regarded as a problem compared to the batch exposure method. .
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 amount of 1,200 J / m ² or less.

On the other hand, from the viewpoint of improving the throughput in the process of manufacturing a liquid crystal display element, there is a process technique “ODF (One Drop Fill) method” in which a liquid crystal material is applied to the surface of a glass substrate before the glass substrates are bonded together. The time required for manufacturing the liquid crystal display element can be greatly reduced by this method. For example, in the case of a 30-inch liquid crystal display element, it takes about 5 days to fill the liquid crystal material with the conventional method, but about 2 hours is sufficient with the ODF method, and the throughput can be greatly improved.
However, in the case of the ODF method, a step of pressure bonding the thin film transistor (TFT) array and the color filter is necessary at room temperature, and when the plastic deformation of the spacer due to the compressive load increases, the uniformity of the cell gap cannot be maintained, A gap is generated in the cell, causing display unevenness.
Therefore, a spacer that is difficult to plastically deform and has a high recovery rate even when subjected to deformation due to a compressive load is required. For example, Patent Document 1 discloses that a monomer having a cyclic imide group, a (meth) acrylic acid monomer, and a hydroxyl group-containing monomer. A spacer composed of a polymer obtained by reacting an ethylenically unsaturated bond-containing isocyanate compound with a polymer and a photosensitive resin composition containing a thermally crosslinkable epoxy group-containing compound has been proposed. It is said to be sensitive and elastic. However, in this photosensitive resin composition, from the viewpoint of developability with respect to an alkaline aqueous solution, the amount of the thermally crosslinkable epoxy group-containing compound that contributes to the improvement in heat resistance is limited, so the heat resistance of the resulting spacer is not always satisfactory. There is a problem that you can not.
JP 2003-173025 A

Therefore, the object of the present invention is to obtain a sufficient spacer shape with high sensitivity and high resolution even at an exposure amount of 1,200 J / m ² or less, elastic recovery, rubbing resistance, adhesion to a transparent substrate, and heat resistance. It is providing the radiation sensitive resin composition which can form the spacer for liquid crystal display elements excellent in these.

  Another object of the present invention is to provide a side chain unsaturated 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.

  Still other objects and advantages of the present invention will become apparent from the following description.

According to the present invention, the problem is firstly
(A1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride; (a2) an epoxy group-containing unsaturated compound; (a3) a hydroxyl group-containing unsaturated compound; and (a4) another unsaturated compound. This is achieved by a polymer obtained by reacting an isocyanate compound represented by the following formula (1) with a polymer (hereinafter referred to as “[A] polymer”).

(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents an alkylene group.)

According to the present invention, the problem is secondly,
It is achieved by a radiation sensitive resin composition comprising [A] a polymer, [B] a polymerizable unsaturated compound, and [C] a radiation sensitive polymerization initiator.

According to the present invention, the problem is thirdly,
It is achieved by a radiation sensitive resin composition (hereinafter referred to as “a radiation sensitive resin composition for spacers for liquid crystal display elements”) used for forming a spacer for liquid crystal display elements, comprising the radiation sensitive resin composition. The

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

According to the present invention, fifthly, the problem is as follows:
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 coating film of a radiation sensitive resin composition for spacers for liquid crystal display elements on a substrate;
(B) a step of exposing at least a part of the coating film;
(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, sixthly, the problem is as follows:
This is achieved by a liquid crystal display element comprising the liquid crystal display element spacer.

  The polymer [A] of the present invention has a carboxyl group and / or a carboxylic acid anhydride group, an epoxy group, and a polymerizable unsaturated bond, has an appropriate solubility in an alkaline aqueous solution, and is specially cured. It can be easily cured by heating without using an agent, and is particularly useful as a resin component of a radiation-sensitive resin composition suitable for forming a spacer in a liquid crystal display device.

The radiation-sensitive resin composition of the present invention has high sensitivity and high resolution, and a sufficient pattern shape can be obtained even with an exposure amount of 1,200 J / m ² or less. Elastic recovery, rubbing resistance, adhesion to a transparent substrate It is possible to form spacers for liquid crystal display elements with excellent heat resistance, etc., and at the time of spacer formation, the post-baking temperature after development can be lowered, which can cause yellowing or deformation of the resin substrate. Absent.

  The liquid crystal display element of the present invention comprises a spacer having excellent performance such as pattern shape, elastic recovery, rubbing resistance, adhesion to a transparent substrate, heat resistance, etc., and expresses high reliability over a long period of time. be able to.

Hereinafter, the present invention will be described in detail.
[A] Polymer The [A] polymer of the present invention comprises (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride, (a2) an epoxy group-containing unsaturated compound, and (a3) a hydroxyl group-containing non-polymer. A copolymer of a saturated compound and (a4) another unsaturated compound (hereinafter referred to as “copolymer [α]”) is used as an isocyanate compound represented by the above formula (1) (hereinafter referred to as “unsaturated”). It consists of a polymer obtained by reacting an isocyanate compound (1) ”.
Among the components constituting the copolymer [α], (a1) unsaturated carboxylic acid and / or unsaturated carboxylic acid anhydride (hereinafter these are collectively referred to as “(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. Acid is preferred.
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 On the other hand, if it exceeds 40% by weight, the solubility of the polymer in an alkaline developer may be too high.

Examples of the (a2) epoxy group-containing unsaturated compound include:
Acrylic epoxies 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 epoxy (cyclo) alkyl esters such as glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate;
such as glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, glycidyl α-n-butyl acrylate, 6,7-epoxyheptyl α-ethyl acrylate, 3,4-epoxycyclohexyl α-ethyl acrylate Other α-alkyl acrylic acid epoxy (cyclo) alkyl esters;
Examples thereof include glycidyl ethers such as o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether.

Among these (a2) epoxy group-containing unsaturated compounds, from the viewpoint of copolymerization reactivity and spacer strength, glycidyl methacrylate, 2-methylglycidyl methacrylate, 6,7-epoxyheptyl methacrylate, 4-hydroxybutyl Acrylate glycidyl ether, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether are preferred.
In the copolymer [α], the (a2) epoxy group-containing unsaturated 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 (a2) epoxy group-containing unsaturated compound is preferably 10 to 70% by weight, more preferably 15 to 60% by weight, and particularly preferably 20 to 50%. % By weight. In this case, if the content of the repeating unit derived from the (a2) epoxy group-containing unsaturated compound is less than 10% by weight, the strength of the obtained spacer tends to decrease, whereas if it exceeds 70% by weight, the unsaturated isocyanate There is a tendency that the storage stability of the polymer obtained by the reaction with the narate compound (1) is lowered.

Examples of the (a3) hydroxyl group-containing unsaturated compound include:
2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, 1,4-cyclohexanedimethanol mono Hydroxyalkyl esters of acrylic acid such as acrylates;
Methacrylic acid hydroxyalkyl esters such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, etc. Can be mentioned.

Of these (a3) hydroxyl group-containing unsaturated compounds, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, , 4-cyclohexanedimethanol monoacrylate and the like are preferable.
In the copolymer [α], the (a3) hydroxyl group-containing unsaturated 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 (a3) hydroxyl group-containing unsaturated compound is preferably 1 to 30% by weight, more preferably 3 to 20% by weight, and particularly preferably 5 to 15% by weight. %. In this case, if the content of the repeating unit derived from the hydroxyl group-containing unsaturated compound (a3) is less than 1% by weight, the introduction rate of the unsaturated isocyanate compound (1) into the polymer tends to decrease and the sensitivity tends to decrease. On the other hand, if it exceeds 30% by weight, the storage stability of the polymer obtained by the reaction with the unsaturated isocyanate compound (1) tends to be lowered.

Moreover, (a4) other unsaturated compounds are unsaturated compounds other than (a1), (a2) and (a3).
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;
Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decane-8-yl, 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 ] decane methacrylate, 2- (tricyclo [5.2.1.0 ^2,6 ] methacrylic acid Decane-8-yloxy) ethyl, methacrylic acid alicyclic esters such as isobornyl methacrylate;
Aryl or aralkyl esters of acrylic acid such as phenyl acrylate, benzyl acrylate;
Aryl or aralkyl esters of methacrylic acid such as phenyl methacrylate or 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 oxygen-containing hetero 6-membered ring such as tetrahydrofuran-2-yl acrylate, tetrahydropyran-2-yl acrylate, 2-methyltetrahydropyran-2-yl acrylate;
Methacrylate esters 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;
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.

Among these (a4) other unsaturated compounds, 2-methylcyclohexyl acrylate, t-butyl methacrylate, methacrylic acid from the viewpoint of copolymerization reactivity and solubility of the obtained [A] polymer in an alkaline aqueous solution. Tricyclo [5.2.1.0 ^2,6 ] decan-8-yl, styrene, p-methoxystyrene, tetrahydrofuran-2-yl methacrylate, and 1,3-butadiene are preferred.

In the copolymer [α], (a4) 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 (a4) another unsaturated compound is preferably 10 to 70% by weight, more preferably 20 to 50% by weight, and particularly preferably 30 to 50% by weight. %. In this case, if the content of the repeating unit derived from (a4) 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 70% by weight, the solubility of the polymer in an alkaline developer tends to decrease.
As the copolymer [α], for example, (a1) an unsaturated carboxylic acid compound, (a2) an epoxy group-containing unsaturated compound, (a3) a hydroxyl group-containing unsaturated compound, and (a4) other unsaturated compounds are suitably used. In a solvent in the presence of a radical polymerization initiator.

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 propionates 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, methyl lactate, ethyl lactate, n-propyl lactate, n-lactic acid Butyl, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, n-propyl 3-hydroxypropionate, 3-hydroxy N-butyl propionate, methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, n-propyl methoxyacetate, n-butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, n-propyl ethoxyacetate, Ethoxyacetic acid n- Chill, n-propoxyacetate methyl, n-propoxyacetate ethyl, n-propoxyacetate n-propyl, n-propoxyacetate n-butyl, n-butoxyacetate methyl, n-butoxyacetate, n-butoxyacetate n-propyl, Other esters such as n-butyl n-butoxyacetate can be mentioned.

Of these solvents, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, and alkyl alkoxypropionate 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 can be obtained by reacting the unsaturated isocyanate compound (1) with the copolymer [α].
In the general formula (1), the alkylene group for R ² is preferably a linear alkylene group having 1 to 12 main chain carbon atoms.

Examples of the unsaturated isocyanate compound (1) include:
Acrylic acid derivatives such as 2-acryloyloxyethyl isocyanate, 3-acryloyloxypropyl isocyanate, 4-acryloyloxybutyl isocyanate, 6-acryloyloxyhexyl isocyanate, 8-acryloyloxyoctyl isocyanate, 10-acryloyloxydecyl isocyanate;
Mention may be made of methacrylic acid derivatives such as 2-methacryloyloxyethyl isocyanate, 3-methacryloyloxypropyl isocyanate, 4-methacryloyloxybutyl isocyanate, 6-methacryloyloxyhexyl isocyanate, 8-methacryloyloxyoctyl isocyanate, 10-methacryloyloxydecyl isocyanate. it can.

Moreover, as a commercial item of 2-acryloyloxyethyl isocyanate, it is a trade name, Karenz AOI (made by Showa Denko KK), and as a commercial item of 2-methacryloyloxyethyl isocyanate, it is a brand name, Karenz MOI (Showa Denko). (Made by Co., Ltd.).
Of these unsaturated isocyanate compounds (1), 2-acryloyloxyethyl isocyanate and 2-methacryloyloxyethyl isocyanate are preferred from the viewpoint of reactivity with the copolymer [α].

[A] In the polymer, the unsaturated isocyanate compound (1) can be used alone or in admixture of two or more.
In the present invention, the reaction between the copolymer [α] and the unsaturated isocyanate compound (1) is carried out, for example, by a catalyst such as di-n-butyltin (IV) dilaurate or a polymerization inhibitor such as p-methoxyphenol. The unsaturated isocyanate compound (1) can be added dropwise to the copolymer [α] solution containing the above while stirring at room temperature or under heating.

  [A] The amount of the unsaturated isocyanate compound (1) used in the production of the polymer is preferably 0.1 to 90 with respect to the (a3) hydroxyl group-containing unsaturated compound in the copolymer [α]. % By weight, more preferably 10 to 80% by weight, particularly preferably 25 to 75% by weight. In this case, if the amount of the unsaturated isocyanate compound (1) used is less than 0.1% by weight, the effect of improving the sensitivity and the elastic properties is small, whereas if it exceeds 90% by weight, the unreacted unsaturated 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, an epoxy group, and a polymerizable unsaturated bond, has an appropriate solubility in an alkaline aqueous solution, and has a special curing agent. It can be easily cured by heating without being used in combination, and can be widely used as a curable resin, but is particularly useful as a resin component of a radiation-sensitive resin composition suitable for forming a spacer in a liquid crystal display element. is there.

Radiation-sensitive resin composition The radiation-sensitive resin composition of the present invention comprises [A] a polymer, [B] a polymerizable unsaturated compound, and [C] a radiation-sensitive polymerization initiator.
[A] A radiation-sensitive resin composition containing a polymer can easily form a spacer having a predetermined shape without developing residue and film loss during development.

-[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 thereof include methoxybutyl acrylate, 3-methoxybutyl methacrylate, (2-acryloyloxyethyl) (2-hydroxypropyl) phthalate, (2-methacryloyloxyethyl) (2-hydroxypropyl) phthalate, and the like. As commercial products, for example, Aronix M-101, M-111, M-114 (above, manufactured by Toa Gosei Co., Ltd.); KAYARAD TC-110S, TC-120S (above, Nippon Chemical Co., Ltd.) Yaku Co., Ltd.); Viscoat 158, 2311 (above, manufactured by Osaka Organic Chemical Industry Co., Ltd.).

  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 a commercial item, it is a brand name, 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.).

  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 (Meth) acrylic acid esters of linear alkylene groups and alicyclic And a compound having two or more isocyanate groups, one or more hydroxyl groups in the molecule, and 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 a compound 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 and 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 1 to 120 parts by weight, more preferably 3 to 100 parts per 100 parts by weight of the [A] polymer. Parts by weight. In this case, if the amount of the [B] polymerizable unsaturated compound used is less than 1 part by weight, there is a risk of developing residue during development, whereas if it exceeds 120 parts by weight, the adhesion of the resulting spacer tends to decrease. There is.

-[C] Radiation sensitive polymerization initiator-
[C] The radiation-sensitive polymerization initiator is an active species capable of initiating polymerization of the polymerizable unsaturated compound by exposure of radiation to visible light, ultraviolet light, far ultraviolet light, charged particle beam, X-ray or the like. Consists of components that occur.
As such [C] radiation sensitive polymerization initiator, for example, 9. H. A carbazole-based O-acyloxime polymerization initiator (hereinafter referred to as “O-acyloxime polymerization initiator (I)”) is preferable.

  Examples of the O-acyloxime polymerization initiator (I) include 1- [9-ethyl-6-benzoyl-9. H. -Carbazol-3-yl] -nonane-1,2-nonane-2-oxime-O-benzoate, 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, 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-benzoate, 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate, 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 and the like.

Of these O-acyloxime type polymerization initiators (I), 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate is preferred.
The O-acyloxime type polymerization initiator (I) can be used alone or in admixture of two or more.
In the present invention, the [C] radiation sensitive polymerization initiator is an O-acyl oxime photopolymerization initiator other than the O-acyl oxime polymerization initiator (I) (hereinafter referred to as “O-acyl oxime polymerization”). One or more initiators (II) ”) may be used in combination.

Examples of the O-acyloxime polymerization initiator (II) include 1,2-octadion-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime), 1,2-butanedione-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime), 1,2-butanedione-1- [4- (phenylthio) phenyl] -2- (O-acetyloxime), 1,2-octadione- 1- [4- (methylthio) phenyl] -2- (O-benzoyloxime), 1,2-octadion-1- [4- (phenylthio) phenyl] -2- (O- (4-methylbenzoyloxime)) Etc.
Of these O-acyloxime type polymerization initiators (II), 1,2-octadion-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime) is particularly preferable.

In the present invention, the O-acyl oxime type polymerization initiator (I) or a mixture thereof and the O-acyl oxime type polymerization initiator (II) (hereinafter collectively referred to as “O-acyl oxime type polymerization initiator”). )), It is possible to obtain a pacer having sufficient sensitivity and good adhesion even with an exposure amount of 1,200 J / m ² or less.

In the radiation-sensitive resin composition of the present invention, the amount of the O-acyloxime polymerization initiator used is preferably 5 to 30 parts by weight, more preferably 100 parts by weight of the [B] polymerizable unsaturated compound. 5 to 20 parts by weight. In this case, if the amount of the O-acyloxime type polymerization initiator used is less than 5 parts by weight, the residual film ratio tends to decrease during development, whereas if it exceeds 30 parts by weight, alkali development of unexposed parts during development occurs. There exists a tendency for the solubility with respect to a liquid to fall.
The proportion of the O-acyloxime polymerization initiator (II) used is 100 parts by weight in total of the O-acyloxime polymerization initiator (I) and the O-acyloxime polymerization initiator (II). , Preferably 30 parts by weight or less, more preferably 20 parts by weight or less.

Furthermore, in the radiation sensitive resin composition of the present invention, one or more other radiation sensitive polymerization initiators can be used in combination with the O-acyloxime type polymerization initiator.
Examples of the other radiation-sensitive polymerization initiator include acetophenone compounds, biimidazole compounds, benzoin compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, xanthone compounds, phosphine compounds, And triazine compounds. Of these, acetophenone compounds and biimidazole compounds are preferred.
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 -On, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenylketone and the like can be mentioned. Examples of the α-aminoketone compound include 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl). ) -Butan-1-one, 2- (4-methylbenzoyl) -2- (dimethylamino) -1- (4-morpholinophenyl) -butan-1-one, and the like. Furthermore, examples of compounds other than these compounds include 2,2-dimethoxyacetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, and the like.

Among these acetophenone compounds, in particular, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2- (4-methylbenzoyl) -2- (dimethylamino) -1- (4-Morpholinophenyl) -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 2,2′-bis (2,4-dichlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2 ′ is particularly preferable. -Biimidazole is particularly 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 and octyl 3-mercaptopropionate; 3,6-dioxa-1,8-octanedithiol And bifunctional or higher aliphatic thiols such as pentaerythritol tetra (mercaptoacetate) and pentaerythritol tetra (3-mercaptopropionate).
Of these thiol compounds, 2-mercaptobenzothiazole is particularly preferable.

In the radiation-sensitive resin composition of the present invention, the use ratio of the other radiation-sensitive polymerization initiator is preferably 100 parts by weight or less, more preferably 80 parts by weight with respect to 100 parts by weight of the total radiation-sensitive polymerization initiator. Part or less, particularly preferably 60 parts by weight or less. In this case, if the use ratio of the other radiation-sensitive polymerization initiator exceeds 100 parts by weight, the intended effect of the present invention may be impaired.
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 50 parts by weight with respect to 100 parts by weight of the biimidazole compound. Preferably it is 1-20 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 be reduced. 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 50 parts by weight, more preferably 100 parts by weight of the biimidazole compound. 1 to 20 parts by weight. In this case, if the addition 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. On the other hand, if the amount exceeds 50 parts by weight, the resulting spacer There is a tendency that the shape of is damaged.
However, in the present invention, only the [C] radiation sensitive polymerization initiator other than the O-acyloxime polymerization initiator (I) can be used alone or in admixture of two or more.

-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.

  The silicone-based surfactant is a commercially available product, for example, Toray Silicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193. SZ-6032, SF-8428, DC-57, DC-190 (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, polyoxyethylene Polyoxyethylene aryl ethers such as n-nonylphenyl ether; nonionic surfactants such as polyoxyethylene dilaurate and polyoxyethylene dialkyl esters such as polyoxyethylene distearate, and commercially available products under the trade name, 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 blending 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 polymer [A]. 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.

As said functional silane coupling agent, the compound which has reactive functional groups, such as a carboxyl group, a methacryloyl group, a vinyl group, an isocyanate group, an epoxy group, can be mentioned, for example. More specifically, trimethoxysilylbenzoic acid, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like can be mentioned.
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] 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 blending amount of the storage stabilizer is preferably 3 parts by weight or less, more preferably 0.001 to 0.5 parts by weight, with respect to 100 parts by weight of the [A] 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, N- (alkoxymethyl) melamine compounds, compounds having two or more epoxy groups, and the like.

  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.

  Examples of the compound having two or more epoxy groups include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diester. Glycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, hydrogenated bisphenol A diglycidyl ether, bisphenol A diglycidyl ether , Ortho-cresol novolac type epoxy resin and commercial products Thus, for example, Epolite 40E, 100E, 200E, 70P, 200P, 400P, 1500NP, 1600, 80MF, 100MF, 3002, and 4000 (above Kyoeisha Chemical Co., Ltd.), EOCN102 103S, 104S, 1020, 1025, 1027 (manufactured by Nippon Kayaku Co., Ltd.), Epicoat 180S (manufactured by Japan Epoxy Resin 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] 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.

-Solvent-
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 From the viewpoints of the reactivity and ease of film formation, alcohols, ethylene glycol monoalkyl ether acetate, diethylene glycol monoalkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, alkyl alkoxypropionate and the like are preferable. Among others, benzyl alcohol, 2-phenylethanol, 3-phenyl-1-propanol, ethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate Particularly preferred are propylene glycol monoethyl ether acetate and the like.

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.

Next, a method for forming the spacer for liquid crystal display element of the present invention (hereinafter also simply referred to as “spacer”) using the radiation-sensitive resin composition of the present invention will be described.

The formation of the spacer of the present invention includes at least the following steps in the order described below.
(A) forming a coating film of the radiation sensitive resin composition of the present invention on a substrate;
(B) a step of exposing at least a part of the coating film;
(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 the transparent substrate, and the radiation-sensitive resin composition is applied onto the transparent conductive film, preferably as a composition solution, and then the coated surface is heated (prebaked). A film is formed.

Examples of the transparent substrate used for forming the spacer include a glass substrate and a resin substrate. More specifically, a glass substrate such as soda lime glass and alkali-free 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 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. However, the spin coating method and the slit die coating method are particularly preferable.
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 coating film is exposed. In this case, when exposing to a part of coating film, it exposes normally through the photomask which has 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, for example, 100 to 10,000 J / m ² , preferably 1,500, as a value obtained by measuring the intensity of the exposed radiation at a wavelength of 365 nm with an illuminometer (OAI model 356, manufactured by OAI Optical Associates Inc.). ˜3,000 J / m ² .

-(C) Process-
Next, the exposed coating film is developed to remove unnecessary portions and form a predetermined pattern.

  As the developer used for development, an alkali developer is preferable. Examples include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia; aliphatic primary amines such as ethylamine and n-propylamine; diethylamine, di-n- Aliphatic secondary amines such as propylamine; aliphatic tertiary amines such as trimethylamine, methyldiethylamine, dimethylethylamine, triethylamine; pyrrole, piperidine, N-methylpiperidine, N-methylpyrrolidine, 1,8-diazabicyclo [5.4 0.0] -7-undecene, alicyclic tertiary amines such as 1,5-diazabicyclo [4.3.0] -5-nonene; aromatic tertiary amines such as pyridine, collidine, lutidine, quinoline; ethanol dimethyl Amine, methyldiethanolamine, trie Examples include aqueous solutions of alkaline compounds such as alkanolamines such as tanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide.

Further, 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 160 ° 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 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 this invention comprises the spacer for liquid crystal display elements of this invention formed as mentioned above.
The structure of the liquid crystal display 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 are arranged via a 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′-azobis (2,4-dimethylvaleronitrile) and 250 parts of diethylene glycol methyl ethyl ether, followed by 17 parts of methacrylic acid and 45 parts of glycidyl methacrylate. , Tricyclo [5.2.1.0 ^2,6 ] decane-8-yl methacrylate, 5 parts styrene, 10 parts 2-hydroxyethyl methacrylate, purged with nitrogen, and then gently stirred. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours for polymerization to obtain a copolymer [α] solution having a solid content concentration of 28.0%.
With respect to the obtained copolymer [α], Mw was measured using GPC (Gel Permeation Chromatography) HLC-8020 (trade name, manufactured by Tosoh Corporation), and it was 18,000.

Next, 5 parts of 2-methacryloyloxyethyl isocyanate (trade name Karenz MOI, manufactured by Showa Denko KK), 0.03 part of di-n-butyltin dilaurate (IV) in the copolymer [α] solution, After adding 0.1 part of 4-methoxyphenol, the mixture was reacted by stirring at 40 ° C. for 3 hours and further at 50 ° C. for 1.5 hours. The progress of the reaction between the isocyanate group of Karenz MOI and the hydroxyl group of the copolymer [α] was confirmed by IR (infrared absorption) spectrum. IR spectra of the polymer solution [α] after the reaction for 1 hour and the solution after the reaction at 40 ° C. for 3 hours and further at 50 ° C. for 1.5 hours are shown in FIGS. 3 (a), (b) and (c), respectively. ). As the reaction progressed, it was confirmed that the peak near 2270 cm ⁻¹ derived from the isocyanate group of Karenz MOI decreased. A [A] polymer solution having a solid content concentration of 29.3% was obtained. Let this [A] polymer be a polymer (A-1).

Synthesis example 2
A flask equipped with a condenser and a stirrer was charged with 7 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) and 250 parts of diethylene glycol methyl ethyl ether, followed by 18 parts of methacrylic acid and 2-methyl methacrylate. 30 parts of glycidyl, 27 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl, 5 parts of styrene, 10 parts of 2-hydroxyethyl methacrylate, 10 parts of tetrahydrofuran-2-yl methacrylate After charging 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 4 hours, whereby a copolymer with a solid content concentration of 29.0% [α A solution was obtained.
With respect to the obtained copolymer [α], Mw was measured by GPC (gel permeation chromatography) HLC-8020 and found to be 11,000.

  Next, 5 parts of 2-methacryloyloxyethyl isocyanate (trade name Karenz MOI, manufactured by Showa Denko KK), 0.03 part of di-n-butyltin dilaurate (IV) in the copolymer [α] solution, After adding 0.1 part of 4-methoxyphenol, the mixture was stirred at 40 ° C. for 3 hours and further stirred at 50 ° C. for 1.5 hours, and the reaction progress was confirmed in the same manner as in Synthesis Example 1 to obtain a solid content. A [A] polymer solution having a concentration of 30.2% was obtained. Let this [A] polymer be a polymer (A-2).

Synthesis example 3
A flask equipped with a condenser and a stirrer was charged with 7 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) and 250 parts of diethylene glycol methyl ethyl ether, followed by 18 parts of methacrylic acid and 2-methyl methacrylate. 30 parts of glycidyl, 27 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 5 parts of styrene, 10 parts of 2-hydroxyethyl methacrylate, 10 parts of tetrahydrofuran-2-yl methacrylate After charging 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 4 hours, whereby a copolymer with a solid content concentration of 29.0% [α A solution was obtained.
With respect to the obtained copolymer [α], Mw was measured by GPC (gel permeation chromatography) HLC-8020 and found to be 11,000.

  Subsequently, 2.5 parts of 2-acryloyloxyethyl isocyanate (trade name Karenz AOI, Showa Denko KK), di-n-butyltin dilaurate (IV) 0.03 was added to the copolymer [α] solution. After adding 0.1 part of 4-methoxyphenol, the mixture was reacted with stirring at 40 ° C. for 3 hours and further at 50 ° C. for 1.5 hours, and the reaction progress was confirmed in the same manner as in Synthesis Example 1. A [A] polymer solution having a solid concentration of 30.2% was obtained. Let this [A] polymer be a polymer (A-3).

Synthesis example 4
A flask equipped with a condenser and a stirrer was charged with 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) and 250 parts of diethylene glycol methyl ethyl ether, followed by 18 parts of methacrylic acid and 45 parts of glycidyl methacrylate. After charging 32 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate and 5 parts of styrene and replacing with nitrogen, the temperature of the solution was raised to 70 ° C. while gently stirring. Then, this temperature was maintained for 4 hours for polymerization to obtain a copolymer solution having a solid content concentration of 28.5%.
About the obtained copolymer, it was 18,000 when Mw was measured using GPC (gel permeation chromatography) HLC-8020. This copolymer is referred to as “polymer (a-1)”.

Synthesis example 5
A flask equipped with a condenser and a stirrer was charged with 4 parts of 2,2′-azobis (2-methylbutyronitrile) and 185 parts of diethylene glycol dimethyl ether, followed by 20 parts of methacrylic acid, 25 parts of benzyl methacrylate, and styrene 35. And 20 parts of 2-hydroxyethyl methacrylate were charged, and after the atmosphere was replaced with nitrogen, the temperature of the solution was raised to 85 ° C. while gently stirring, and this temperature was maintained for 2 hours for polymerization. By polymerizing for 1 hour, a copolymer solution having a solid content concentration of 34.0% was obtained.
It was 28,000 when Mw was measured using GPC (gel permeation chromatography) HLC-8020 about the obtained copolymer.

  Subsequently, 5 parts of 2-methacryloyloxyethyl isocyanate (trade name Karenz MOI, manufactured by Showa Denko KK), 0.03 part of dibutyltin dilaurate (IV), 0.1 part of 4-methoxyphenol are added to the copolymer solution. The resulting mixture was reacted at 40 ° C. for 3 hours and further at 50 ° C. for 1.5 hours to obtain a polymer solution having a solid content concentration of 35.2%. This polymer is referred to as “polymer (a-2)”.

Example 1
Preparation of Composition Solution As [A] component, 100 parts of polymer solution (A-1) obtained in Synthesis Example 1 as polymer (A-1), and as component [B], dipentaerystol hexaacrylate (trade name) KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.) 80 parts, [C] component, 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate (trade name CGI-242, manufactured by Ciba Specialty Chemicals), γ-glycidoxypropyltrimethoxysilane as an adhesion aid 5 parts, 0.5 parts FTX-218 (trade name, manufactured by Neos Co., Ltd.) as a surfactant and 0.5 parts 4-methoxyphenol as a storage stabilizer are mixed to a solid content concentration of 30%. After being dissolved in propylene glycol monomethyl ether acetate, it was filtered through a Millipore filter having a pore size of 0.5 μm to prepare a composition solution. Table 1 shows the composition ratio of the main component.

Formation of Spacer The composition solution was applied onto an alkali-free glass substrate using a spinner, and then pre-baked on a hot plate at 90 ° C. for 3 minutes to form a film having a thickness of 6.0 μm.
Subsequently, the obtained coating film was exposed to ultraviolet rays having an intensity of 365 W / m ² at 365 nm for 10 seconds through a photomask having a remaining pattern of 10 μm square. Thereafter, development was performed with a 0.05 wt% aqueous solution 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 220 ° C. for 60 minutes to form a spacer.

  Next, various evaluations were performed in the following manner. The evaluation results are shown in Table 4 and Table 5.

(1) Evaluation of sensitivity When the spacer was formed in the same manner as the spacer except that the exposure amount was changed, the residual film ratio after development (film thickness after development × 100 / initial film thickness. The same applies hereinafter. The exposure amount at which 90) is 90% or more was defined as sensitivity. When this exposure amount is 1,500 J / m ² or less, it can be said that the sensitivity is good.

(2) Evaluation of resolution The minimum resolution that can be resolved by the exposure amount when the remaining film ratio after development is 90% or more when the spacer is formed in the same manner as the formation of the spacer except that the exposure amount is variable. Evaluation was based on the pattern size.

(3) Evaluation of cross-sectional shape The cross-sectional shape of the obtained spacer was observed with a scanning electron microscope and evaluated according to which of A to D shown in FIG. At this time, when the pattern edge is forward tapered or vertical like A or B, it can be said that the cross-sectional shape is good. On the other hand, as shown in C, when the sensitivity is insufficient, the remaining film rate is low, the cross-sectional dimension is small compared to A and B, and the bottom surface is a semi-convex lens shape with a flat surface, the cross-sectional shape is Also, as shown in D, the pattern may be peeled off during the subsequent rubbing process even in the case of an inversely tapered shape (in the cross-sectional shape, an inverted triangular shape in which the side of the film surface is longer than the side on the substrate side). Since it became very large, the cross-sectional shape was regarded as defective.

(4) Evaluation of elastic recovery rate About the obtained spacer, using a micro compression tester (trade name MCTM-200, manufactured by Shimadzu Corporation), a flat indenter with a diameter of 50 μm was used to adjust both the loading speed and the 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. 5, the difference between the deformation amount at the load of 50 mN and the deformation amount at the load of 5 mN is L1, and the deformation amount at the load of 50 mN and the deformation amount at the load of 5 mN at the time of unloading. The elastic recovery rate was calculated by the following formula, with the difference between L2 and L2.
Elastic recovery rate (%) = L2 × 100 / L1

(5) 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 shaving or peeling was evaluated.

(6) 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 3.

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

Examples 2-24, Comparative Examples 1-6
Each component shown in Tables 1 to 3 was used as an adhesion aid, 5 parts of γ-glycidoxypropyltrimethoxysilane, as a surfactant, 0.5 part of FTX-218, and as a storage stabilizer, 4-methoxyphenol. After mixing with 0.5 part and dissolving in propylene glycol monomethyl ether acetate to a solid content concentration of 30%, the solution was filtered through a Millipore filter with a pore size of 0.5 μm to prepare a composition solution. Thereafter, in the same manner as in Example 1, a spacer was formed and evaluated. The evaluation results are shown in Table 4 and Table 5.

  In Tables 1-3, each component other than the polymer is as follows.

[B] Component B-1: Dipentaerystol hexaacrylate (trade name KAYARAD DPHA)
B-2: Commercial product containing a polyfunctional urethane acrylate compound (trade name KAYARAD DPHA-40H)

[C] component C-1: 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate (trade name CGI-242, manufactured by Ciba Specialty Chemicals)
C-2: 1,2-octadion-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime) (trade name CGI-124, manufactured by Ciba Specialty Chemicals)

D-1: 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (trade name Irgacure 907, manufactured by Ciba Specialty Chemicals)
D-2: 2- (4-methylbenzoyl) -2- (dimethylamino) -1- (4-morpholinophenyl) -butan-1-one

E-1: 2,2′-bis (2,4-dichlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole E-2: 4,4′-bis (diethylamino) ) Benzophenone E-3: 2-mercaptobenzothiazole

It is a schematic diagram which shows an example of the structure of a liquid crystal display element. It is a schematic diagram which shows the other example of the structure of a liquid crystal display element. It is the IR spectrum figure which tracked the reaction course at the time of manufacturing the polymer of the present invention. It is a schematic diagram which illustrates the cross-sectional shape of a spacer. 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 (6)

(A1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride; (a2) an epoxy group-containing unsaturated compound; (a3) a hydroxyl group-containing unsaturated compound; and (a4) another unsaturated compound. A polymer obtained by reacting an isocyanate compound represented by the following formula (1) with a polymer.
(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents an alkylene group.) [A] A radiation-sensitive resin composition comprising the polymer according to claim 1, [B] a polymerizable unsaturated compound, and [C] a radiation-sensitive polymerization initiator. The radiation sensitive resin composition used for formation of the spacer for liquid crystal display elements which consists of a radiation sensitive resin composition of Claim 2. The spacer for liquid crystal display elements formed from the radiation sensitive resin composition of Claim 3. 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 coating film of the radiation sensitive resin composition according to claim 3 on a substrate;
(B) a step of exposing at least a part of the coating film;
(C) a step of developing the coated film after exposure, and (d) a step of heating the coated film after development. A liquid crystal display device comprising the spacer according to claim 4.