JP2006276847A - Radiation sensitive resin composition and spacer for liquid crystal display element - Google Patents

Abstract

[PROBLEMS] To provide a liquid crystal with high sensitivity, high resolution, sufficient spacer shape even at an exposure amount of about 1,200 J / m ² or less, and excellent in elastic recovery, rubbing resistance, adhesion to a substrate, heat resistance, and the like. A radiation-sensitive resin composition capable of forming a display element spacer.
A copolymer (α) of an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride, a hydroxyl group-containing unsaturated compound, and another unsaturated compound is mixed with a diisocyanate compound and a hydroxyl group-containing polymerizable unsaturated group. A radiation-sensitive resin composition containing a polymer [A] obtained by reacting a free isocyanate group-containing unsaturated compound (β) obtained by reaction with a compound.
[Selection figure] None

Description

  The present invention relates to a radiation-sensitive resin composition particularly suitable for forming a spacer for a liquid crystal display element, a spacer for a liquid crystal display element and a method for forming the same, and a liquid crystal display element having the liquid crystal display element spacer.

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 coating film of a radiation-sensitive resin composition is formed on a substrate, exposed to, for example, ultraviolet rays through a predetermined photomask, and developed to form dot-like or stripe-like spacers. Since the spacer can be formed only at a predetermined place other than the pixel formation region, the above-described problem is basically solved.

In recent years, the mother glass substrate has been increased in size (for example, about 1,500 × 1,800 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 size is about the same as the substrate size. It is almost impossible to produce a mask, 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 case of the step exposure method, it is necessary to lower the exposure amount at each time, which is conventionally used for forming a spacer. In the radiation sensitive resin composition, it was difficult to achieve a sufficient spacer shape and film thickness with an exposure dose 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, a process technique “ODF (One Drop Fill) method” in which a liquid crystal material is applied to the substrate surface before the substrates are bonded together is introduced. Thus, the time required for manufacturing the liquid crystal display element can be greatly shortened 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, it is difficult to plastically deform, and a spacer having a high recovery rate is required even when subjected to deformation due to a compressive load. A spacer formed from 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 aqueous alkali solution, the amount of the thermally crosslinkable epoxy group-containing compound that contributes to improvement in heat resistance is limited. There is a problem of not being satisfied.
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 about 1,200 J / m ² or less, elastic recovery, rubbing resistance, adhesion to a 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.

The present invention, first,
A copolymer (α) of (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride, (a2) a hydroxyl group-containing unsaturated compound, and (a3) another unsaturated compound, (b1) the following formula ( [A] a polymer obtained by reacting the free isocyanate group-containing unsaturated compound (β) obtained by reacting the diisocyanate compound represented by 1) with the (b2) hydroxyl group-containing polymerizable unsaturated compound It consists of the radiation sensitive resin composition characterized by the above-mentioned.

[In Formula (1), W shows either of the bivalent group represented by each of following formula (i)-(ix).

(However, n is an integer of 1-12.)

]

The present invention secondly,
It consists of the said radiation sensitive resin composition used for formation of the spacer for liquid crystal display elements.

Third, the present invention
It consists of the spacer for liquid crystal display elements formed from the radiation sensitive resin composition used for formation of the said spacer for liquid crystal display elements.

The present invention fourthly,
It consists of the formation method of the spacer for liquid crystal display elements characterized by including the following processes in the order as 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.

The present invention fifthly,
The liquid crystal display element comprises the liquid crystal display element spacer.

The radiation-sensitive resin composition of the present invention has high sensitivity and high resolution, and a sufficient spacer shape can be obtained even at an exposure amount of 1,200 J / m ² or less. Elastic recovery, rubbing resistance, adhesion to a substrate, Spacers for liquid crystal display elements with excellent heat resistance can be formed, and post-baking temperature after development can be lowered at the time of spacer formation, so that the resin substrate does not turn yellow or deform. .
In particular, the elastic recovery is so excellent that the elastic recovery rate defined later shows 80% or more.
Further, according to the method for forming a spacer for a liquid crystal display element of the present invention, a spacer for a liquid crystal display element having excellent characteristics can be formed with high productivity.
In addition, the liquid crystal display element of the present invention is provided with a spacer having excellent performance such as pattern shape, elastic recovery, rubbing resistance, adhesion to a substrate and heat resistance, and exhibits high reliability over a long period of time. can do.

  Hereinafter, the present invention will be described in detail.

Radiation-sensitive resin composition-[A] polymer-
The polymer [A] in the radiation-sensitive resin composition of the present invention comprises (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride (hereinafter collectively referred to as “(a1) an unsaturated carboxylic acid compound”. And (a2) a copolymer (α) of a hydroxyl group-containing unsaturated compound and (a3) another unsaturated compound, (b1) a diisocyanate compound represented by the above formula (1) (hereinafter, “ (B1) a diisocyanate compound ”) and (b2) a polymer obtained by reacting a free isocyanate group-containing unsaturated compound (β) obtained by reacting with a hydroxyl group-containing polymerizable unsaturated compound.
Among the components constituting the copolymer [α], as the (a1) unsaturated carboxylic acid compound, for example,
Acrylic acid, methacrylic acid, crotonic acid, succinic acid mono (2-acryloyloxyethyl), succinic acid mono (2-methacryloyloxyethyl), hexahydrophthalic acid mono (2-acryloyloxyethyl), hexahydrophthalic acid mono ( Monocarboxylic acids such as 2-methacryloyloxyethyl);
Dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid and the like;
The 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. (A1) When the content of the repeating unit derived from the unsaturated carboxylic acid compound is less than 5% by weight, the solubility of the polymer obtained by the reaction with the free isocyanate group-containing unsaturated compound (β) in an 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.

Moreover, as a hydroxyl-containing unsaturated compound which is (a2) component, for example,
2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, 1,4-cyclohexanedimethanol mono Hydroxy (cyclo) alkyl esters of acrylic acid such as acrylates;
2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, 1,4-cyclohexanedimethanol mono Methacrylic acid hydroxy (cyclo) alkyl esters such as methacrylate;
Examples include α-hydroxymethyl acrylate esters such as methyl α- (hydroxymethyl) acrylate, ethyl α- (hydroxymethyl) acrylate, and α- (hydroxymethyl) acrylate n-propyl.

Of these hydroxyl group-containing unsaturated compounds, 4-hydroxybutyl acrylate and 1,4-cyclohexanedimethanol monoacrylate are preferred in terms of copolymerization reactivity and reactivity with the free isocyanate group-containing unsaturated compound (β). , 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, ethyl α- (hydroxymethyl) acrylate and the like are preferable.
In the copolymer (α), the hydroxyl group-containing unsaturated compound can be used alone or in admixture of two or more.
In the copolymer (α), the content of repeating units derived from the hydroxyl group-containing unsaturated compound is preferably 1 to 50% by weight, more preferably 3 to 30% by weight. When the content of the repeating unit derived from the hydroxyl group-containing unsaturated compound is less than 1% by weight, the introduction rate of unsaturated bonds into the polymer obtained by the reaction with the free isocyanate group-containing unsaturated compound (β) decreases. Thus, the sensitivity tends to decrease. On the other hand, when it exceeds 50% by weight, the storage stability of the polymer in a solution state tends to decrease.
In addition, other unsaturated compounds that are the component (a3), that is, other unsaturated compounds different from the components (a) and (a2) can include an epoxy group-containing unsaturated compound and other compounds. . Epoxy group-containing unsaturated compounds are preferred.

Examples of the epoxy group-containing unsaturated compound include:
Acrylic acid epoxy such as glycidyl acrylate, 2-methylglycidyl acrylate, 4-glycidyloxybutyl acrylate, 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate, 3,4-epoxycyclohexyl acrylate (Cyclo) alkyl esters;
Methacrylic acid epoxy such as glycidyl methacrylate, 2-methylglycidyl methacrylate, 4-glycidyloxybutyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate (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;
Examples thereof include glycidyl ethers such as o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether.

  Of these epoxy group-containing unsaturated compounds, 4-glycidyloxybutyl acrylate, glycidyl methacrylate, 2-methylglycidyl methacrylate, and methacrylic acid 6,7- Epoxy heptyl, o-vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether, p-vinyl benzyl glycidyl ether and the like are preferable.

  In the copolymer [α], the content of the repeating unit derived from the epoxy group-containing unsaturated compound is usually 70% by weight or less, preferably 10 to 70% by weight, more preferably 15 to 60% by weight, particularly preferably. Is 20 to 50% by weight. When the content of the repeating unit derived from the epoxy group-containing unsaturated compound exceeds 70% by weight, the storage stability of the polymer obtained by the reaction with the free isocyanate group-containing unsaturated compound (β) is in solution. There is a tendency to decrease. In addition, when the content rate of the repeating unit derived from an epoxy group containing unsaturated compound is less than 10 weight%, there exists a possibility that the sclerosis | hardenability by heating may fall or the improvement effect of the intensity | strength of the spacer obtained may fall.

Moreover, as other unsaturated compounds other than the epoxy group-containing unsaturated compound, 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;
Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-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 ] decane-8-yl 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 diesters 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;
Conjugated diene compounds such as 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene; and acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinylidene chloride, vinyl acetate, etc. Can do.

Among these unsaturated compounds other than these epoxy group-containing unsaturated compounds, 2-methylcyclohexyl acrylate, methacrylic acid from the viewpoint of copolymerization reactivity and solubility of the obtained [A] polymer in an alkaline developer. Preferred are t-butyl, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, tetrahydrofuran-2-yl methacrylate, styrene, p-methoxystyrene, 1,3-butadiene and the like.

In the copolymer [α], other unsaturated compounds other than the epoxy group-containing unsaturated compound can be used alone or in admixture of two or more.
In the copolymer [α], the content of repeating units derived from other unsaturated compounds other than the epoxy group-containing unsaturated compound is preferably 10 to 70% by weight, more preferably 20 to 50% by weight, particularly preferably. Is 30 to 50% by weight. When the content of the repeating unit derived from another unsaturated compound is less than 10% by weight, the storage stability of the polymer obtained by the reaction with the free isocyanate group-containing unsaturated compound (β) is lowered. On the other hand, if it exceeds 70% by weight, the solubility of the polymer in an alkaline developer tends to decrease.
The copolymer (α) is obtained, for example, by polymerizing (a1) an unsaturated carboxylic acid compound, a hydroxyl group-containing unsaturated compound and another unsaturated compound in a suitable solvent in the presence of a radical polymerization initiator. Can be manufactured.

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; and methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, Methyl hydroxyacetate, ethyl hydroxyacetate, hydro N-propyl cyanoacetate, n-butyl hydroxyacetate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, Methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, n-propyl 3-hydroxypropionate, n-butyl 3-hydroxypropionate, methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, N-propyl methoxyacetate, n-butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, n-propyl ethoxyacetate, n-butyl ethoxyacetate, methyl n-propoxyacetate, ethyl n-propoxyacetate, n-propoxyacetate n- Propyl, n-propoxyacetic acid Other esters such as n-butyl, methyl n-butoxyacetate, ethyl n-butoxyacetate, n-butoxyacetate n-propyl, n-butoxyacetate and the like can be mentioned.

Of these solvents, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, alkyl alkoxypropionate 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 synthesis of the [A] polymer, or once separated from the solution and used for the synthesis 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 spacer shape, heat resistance, etc. may be impaired. If it exceeds 1, the resolution may be lowered, or the spacer shape may be impaired.

Next, the free isocyanate group-containing unsaturated compound (β) used in the synthesis of [A] copolymer will be described.
The free isocyanate group-containing unsaturated compound (β) includes (b1) a diisocyanate compound represented by the above formula (1) (hereinafter referred to as “(b1) diisocyanate compound”) and (b2) a hydroxyl group-containing unsaturated compound. It is obtained by the reaction with.
(B1) Among the diisocyanate compounds, examples of the compound in which W in Formula (1) (hereinafter simply referred to as “W”) is a group represented by Formula (i) include 2,3-tolylene diisocyanate, 2,4-tolylene diisocyanate, 2,5-tolylene diisocyanate, 2,6-tolylene diisocyanate, etc .; examples of the compound in which W is a group represented by the formula (iv) include 1,2-ethylene diisocyanate , Trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate and the like; Examples of the compound in which W is a group represented by the formula (ix) include 2,5-bis (isocyanatomethyl) bicyclo [2 2.1] heptane, 2,6-bis (isocyanatomethyl) bicyclo [2. .1] heptane, and the like can be mentioned.

In addition, the compound in which W is a group represented by the formula (ii) is diphenylmethane-4,4′-diisocyanate, and the compound in which W is a group represented by the formula (iii) is dicyclohexylmethane-4,4′-. The compound which is a diisocyanate and is a group represented by the formula (v) is 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, and the compound which is a group represented by the formula (vi) is m-xylylene diisocyanate And the compound represented by the formula (vii) is 1,3-disicocyanatomethylcyclohexane, and the compound represented by the formula (viii) is 1,3-di (2-isocyanate). Natopropyl-2-yl) benzene.
Moreover, (b1) As a commercial item of a diisocyanate compound, it is a brand name, Cosmonate T-80, T-65, T-100, M-100, M-200, M-50, M. -300, the same M-1500, the same MX, the same CX, the same PH, the same NBDI, the Takenate 80, the same 500, the same 600, and the same 700 (above, manufactured by Mitsui Takeda Chemical Co., Ltd.).

Among these (b1) diisocyanate compounds, 2,4-tolylene diisocyanate, (3-isocyanate, from the point of reactivity with the hydroxyl group-containing polymerizable unsaturated compound or copolymer (α) as component (b2). Methyl-3,5,5-trimethylcyclohexyl isocyanate), hexamethylene diisocyanate, a compound represented by formula (1) in which W is represented by formula (ix), and the like are preferable.
In particular, 2,5-bis (isocyanatomethyl) bicyclo [2.2.1] heptane is preferable in achieving high sensitivity and a high elastic recovery rate. In the free isocyanate group-containing unsaturated compound (β), the (b1) diisocyanate compound can be used alone or in admixture of two or more.

Among the hydroxyl group-containing polymerizable unsaturated compounds as the component (b2), examples of the monofunctional hydroxyl group-containing polymerizable unsaturated compound with respect to the polymerization reaction include the compounds exemplified for the hydroxyl group-containing unsaturated compound as the component (a2): The same can be mentioned.
Examples of the polymerizable unsaturated compound having two or more functional groups for the polymerization reaction include 2-hydroxypropyl-1,3-diacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, 2-hydroxypropyl-1 , 3-dimethacrylate, pentaerythritol trimethacrylate, dipentaerythritol pentamethacrylate and the like.

Of these hydroxyl group-containing unsaturated compounds, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, and (b1) in terms of reactivity with the diisocyanate compound, , 4-cyclohexanedimethanol monoacrylate and the like are preferable.
In the free isocyanate group-containing unsaturated compound (β), the hydroxyl group-containing unsaturated compound can be used alone or in admixture of two or more.
The free isocyanate group-containing unsaturated compound (β) is, for example, in a solution containing (b1) a diisocyanate compound, a catalyst such as di-n-butyltin (IV) dilaurate, and a polymerization inhibitor such as p-methoxyphenol. It can be synthesized by gradually dropping and reacting the hydroxyl group-containing unsaturated compound, for example, over 3 to 5 hours while stirring at a temperature of 10 ° C. or lower. In this reaction, it is preferable to use (b1) the diisocyanate compound and the hydroxyl group-containing unsaturated compound in equimolar to substantially equimolar amounts.

Next, [A] the reaction of the copolymer (α) in synthesizing the polymer with the free isocyanate group-containing unsaturated compound (β) includes, for example, converting the copolymer (α) to dilaurate di- It dissolves in a suitable solvent together with a catalyst such as n-butyltin (IV) and a polymerization inhibitor such as p-methoxyphenol, and this solution is stirred at room temperature or under heating while containing a free isocyanate group. For example, the compound (β) can be synthesized by gradually dropping and reacting the compound (β) over 3 to 5 hours.
As said solvent, the thing similar to the solvent illustrated about the synthesis | combination of the said copolymer ((alpha)) can be used, for example.
Of these solvents, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, alkyl alkoxypropionate and the like are preferable.
The said solvent can be used individually or in mixture of 2 or more types.

  [A] The amount of the free isocyanate group-containing unsaturated compound (β) used in the synthesis of the polymer is (a2) 100 parts by weight of the hydroxyl group-containing unsaturated compound used for the synthesis of the copolymer (α). On the other hand, it is preferably 0.1 to 90 parts by weight, more preferably 10 to 80 parts by weight, and particularly preferably 25 to 75 parts by weight. If the amount of the free isocyanate group-containing unsaturated compound (β) used is less than 0.1 parts by weight, the effect of improving the sensitivity and elastic recovery tends to decrease, whereas if it exceeds 90 parts by weight, unreacted free The isocyanate group-containing unsaturated compound (β) remains, and the storage stability of the resulting polymer or radiation-sensitive resin composition in a solution state tends to be lowered.

[A] The polymer has a carboxyl group and / or a carboxylic anhydride group and has good solubility in an alkali developer. In addition, the [A] polymer has a polymerizable unsaturated bond and has curability, but if it further has an epoxy group, the curability is further improved and a special curing agent is not used in combination. It can be easily cured by heating. Accordingly, the radiation-sensitive resin composition of the present invention containing the [A] polymer can easily form a spacer having a predetermined shape without developing residue and film loss when developing with an alkaline developer. it can.
The radiation-sensitive resin composition of the present invention comprises [A] a polymer as an essential component, and further contains the following [B] polymerizable unsaturated compound and [C] a radiation-sensitive polymerization initiator. It is preferable to do.

-[B] polymerizable unsaturated compound-
The polymerizable unsaturated compound is composed of an unsaturated compound that is polymerized by exposure to radiation in the presence of [C] a radiation-sensitive polymerization initiator.
Such a polymerizable unsaturated compound is not particularly limited. For example, a monofunctional, bifunctional, or trifunctional or higher (meth) acrylic acid ester with respect to a polymerization reaction has good copolymerizability, It is preferable because the strength of the obtained spacer is high.

  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 Kayaku) 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, and 1,9-nonanediol dimethacrylate. Also, 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 (or more). , 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, tri- or more functional (Meth) acrylic acid esters, especially those with 9 or more functional groups, And a compound having an alicyclic structure and two or more isocyanate groups, one or more hydroxyl groups in the molecule, and three, four or five acryloyloxy groups and / or Or the polyfunctional urethane acrylate type compound obtained by making it react with the compound which has a methacryloyloxy group 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 Toa Gosei Co., Ltd.), KAYARAD TMPTA, DPHA, DPCA-20, DPCA-30, DPCA-60, DPCA-60, (above, Nippon Kayaku Co., Ltd.), Biscoat 295, 300, 360, 400, GPT, 3PA (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 polymerizable unsaturated compound used is preferably 1 to 120 parts by weight, more preferably 3 to 100 parts by weight with respect to 100 parts by weight of the polymer (A). is there. If the amount of the polymerizable unsaturated compound used is less than 1 part by weight, there may be a residual image during development, while if it exceeds 120 parts by weight, the adhesion of the resulting spacer to the substrate tends to be reduced.

-[C] Radiation sensitive polymerization initiator-
The radiation-sensitive polymerization initiator is composed of a component that generates active species capable of initiating polymerization of a polymerizable unsaturated compound by exposure to radiation such as visible light, ultraviolet light, far ultraviolet light, charged particle beam, and X-ray.
As such a 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, as the radiation-sensitive polymerization initiator, an O-acyl oxime photopolymerization initiator other than the O-acyl oxime polymerization initiator (I) (hereinafter referred to as “O-acyl oxime polymerization initiator ( II) ")) can 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 good sensitivity and good adhesion to the substrate 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. 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, the unexposed part dissolves in the alkaline developer during development. Tend to decrease.
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 initiators 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-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- (4-methylbenzoyl) ) -2- (dimethylamino) -1- (4-morpholinophenyl) -butan-1-one, and the like. 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, 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, by using an acetophenone compound in combination, it is possible to further improve the sensitivity, the shape of the obtained spacer and the compressive strength.

  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 4 ′, 5,5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (2,4-dibromophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2 Examples include '-biimidazole, 2,2'-bis (2,4,6-tribromophenyl) -4,4', 5,5'-tetraphenyl-1,2'-biimidazole, and the like.

  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 preferred.

In the present invention, by using a biimidazole compound in combination, it is possible to further improve the sensitivity, resolution, and adhesion of the resulting spacer to the substrate.
When a biimidazole compound is used in combination, an aliphatic or aromatic compound having a dialkylamino group (hereinafter referred to as “amino sensitizer”) can be added to sensitize it.
Examples of the amino sensitizer include N-methyldiethanolamine, 4,4′-bis (dimethylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, ethyl p-dimethylaminobenzoate, and p-dimethylaminobenzoate. An acid i-amyl etc. can be mentioned.

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.
Furthermore, when using a biimidazole compound and an amino sensitizer together, 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. There are 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 converted to neutral imidazole. At the same time, a component having a sulfur radical having a high polymerization initiating ability is generated, whereby the spacer shape can be made a more preferable forward tapered shape.

Examples of the thiol compound include aromatic compounds such as 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole, 2-mercapto-5-methoxybenzothiazole, and 2-mercapto-5-methoxybenzimidazole. Aliphatic monothiols such as 3-mercaptopropionic acid, methyl 3-mercaptopropionate, ethyl 3-mercaptopropionate, octyl 3-mercaptopropionate; 3,6-dioxa-1,8-octanedithiol, pentaerythritol Bifunctional or higher aliphatic thiols such as tetra (mercaptoacetate) and pentaerythritol tetra (3-mercaptopropionate) can be exemplified.
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. When the usage-amount of another radiation sensitive polymerization initiator exceeds 100 weight part, there exists a possibility that the desired effect of this invention may be impaired.
Moreover, when using a biimidazole compound and an amino sensitizer together, the addition amount of an amino sensitizer is preferably 0.1 to 50 parts by weight, more preferably 1 to 50 parts by weight with respect to 100 parts by weight of the biimidazole compound. 20 parts by weight. 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 of the resulting spacer to the substrate tends to be reduced. There is a risk of damage.

Moreover, when using a biimidazole compound and an amino sensitizer together, the addition amount of a thiol compound is preferably 0.1 to 50 parts by weight, more preferably 1 to 20 parts by weight with respect to 100 parts by weight of the biimidazole compound. Part. If the addition amount of the thiol compound is less than 0.1 parts by weight, the effect of improving the spacer shape tends to be reduced or the film tends to be reduced. On the other hand, if it exceeds 50 parts by weight, the spacer shape may be impaired. .
However, in this invention, only radiation sensitive polymerization initiators other than O-acyl oxime type polymerization initiator (I) can be used individually or in mixture of 2 or more types.
-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 surfactant and a silicone surfactant are preferable.

  The fluorine surfactant is preferably a compound having a fluoroalkyl group or a fluoroalkylene group at least in any of the terminal, main chain and side chain, and specific examples thereof include 1,1,2,2-tetra Fluorooctyl (1,1,2,2-tetrafluoro-n-propyl) ether, 1,1,2,2-tetrafluoro-n-octyl (n-hexyl) ether, octaethylene glycol di (1,1,1, 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-pe Til) 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 Examples thereof include ammonium iodide, fluoroalkyl betaine, fluoroalkyl polyoxyethylene ether, perfluoroalkyl polyoxyethanol, perfluoroalkyl alkoxylate, and fluorine alkyl ester.

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

  As the silicone surfactant, as a commercial product, for example, Toray Silicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, Same SZ-6032, Same SF-8428, Same DC-57, Same DC-190 (above, manufactured by Toray Dow Corning Silicone Co., Ltd.), TSF-4300, Same 4440, Same 4445, Same 4446, -4442, -4460 (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 dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate, and commercially available products under the trade name, for example, KP341 (Shin-Etsu Chemical Co., Ltd.), Polyflow No. 57, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.).
These 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]. When the compounding amount of the surfactant exceeds 5 parts by weight, there is a tendency that film roughening tends to occur during coating.
The adhesion assistant is a component having an effect of further improving the adhesion of the obtained spacer to 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] polymer. When the blending amount of the adhesion assistant exceeds 20 parts by weight, there is a tendency that a development residue tends 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. When the amount of the storage stabilizer exceeds 3 parts by weight, the sensitivity may be lowered and the spacer 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 can be mentioned.

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 (ethoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (n-propoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (i-propoxymethyl) melamine, N, N, N ′, N ′, N ″, N ″ -hexa (n-butoxymethyl) melamine, N, N , N ′, N ′, N ″, N ″ -hexa (t-butoxymethyl) melamine and the like.
Among these N- (alkoxymethyl) melamine compounds, N, N, N ′, N ′, N ″, N ″ -hexa (methoxymethyl) melamine is particularly preferable. For example, Nicalac N-2702, MW-30M (manufactured by Sanwa Chemical Co., Ltd.) and the like can be mentioned.

  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 For example, Epolite 40E, 100E, 200E, 70P, 200P, 400P, 1500NP, 80MF, 100MF, 1600, 3002, 4000 (above, manufactured by 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. When the blending amount of the heat resistance improver exceeds 30 parts by weight, the storage stability of the radiation sensitive resin composition in a solution state tends to be lowered.
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 reactivity and ease of film formation, alcohols, ethylene glycol monoalkyl ether acetates, diethylene glycol monoalkyl ether acetates, diethylene glycol alkyl ethers, propylene glycol monoalkyl ether acetates, alkyl alkoxypropionates, and the like are preferable. Alcohol, 2-phenylethanol, 3-phenyl-1-propanol, ethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dimethyl ether, Ethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate are preferred.
These solvents can be used alone or in admixture of two or more.

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 a liquid crystal display element of the present invention using the radiation sensitive resin composition of the present invention will be described.
The method for forming a spacer for a liquid crystal display element of the present invention includes at least the following steps in the order described below.
(A) a step of 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 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.
As a method of forming a film of the photosensitive resin composition of the present invention, for example, (1) a coating method and (2) a dry film method can be used.

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 obtained by applying or baking a silicone mold release agent on the surface of a synthetic resin film such as a PET film, a polypropylene film, a polyethylene film, or a polyvinyl chloride film may be used. it can. 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 amount is usually 100 to 10,000 J / m ² 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.). The radiation-sensitive resin composition of the invention can obtain a sufficient spacer shape even with an exposure amount of about 1,200 J / m ² or less.

-(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 the development, for example, after washing with running water for 30 to 90 seconds, a desired spacer-shaped film is formed by air-drying with compressed air or compressed nitrogen.

-(2) Process-
Next, the obtained spacer-shaped film 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 example, 30 to 30 in the oven, using a heating device such as a hot plate or an oven. A predetermined spacer for a liquid crystal display element can be obtained by heating (post-baking) for 180 minutes.
Although the conventional radiation sensitive resin composition used for formation of the spacer for liquid crystal display elements did not perform heat processing at the temperature of about 180-200 degreeC or more, the obtained spacer was not able to exhibit sufficient performance. In the radiation sensitive resin composition of the present invention, 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, substrate The spacer for liquid crystal display elements which is excellent in various performances, such as adhesiveness, can be formed.

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 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 substrate, and two liquid crystal layers are arranged via the liquid crystal layer. A structure having an alignment film, an opposing transparent electrode, an opposing substrate, 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 substrate, and are opposed to a thin film transistor (TFT) array through an alignment film and a liquid crystal layer, so that a TN-TFT type liquid crystal display element is obtained. It can also be. 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 (isobutyronitrile) and 250 parts of diethylene glycol methyl ethyl ether, followed by 17 parts of methacrylic acid and 20 parts of 2-hydroxyethyl methacrylate. Then, 20 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 23 parts of benzyl methacrylate and 20 parts of tetrahydrofuran-2-yl methacrylate were charged, and the atmosphere was gradually replaced with nitrogen. While stirring, the temperature of the solution was raised to 90 ° C., and this temperature was maintained for 5 hours for polymerization to obtain a copolymer (α) solution having a solid content concentration of 29.0%. The coalescence (α) is referred to as “copolymer (α-1)”.
It was 20,000 when Mw was measured about the obtained copolymer ((alpha) -1) using GPC (gel permeation chromatography) HLC-8020 (brand name, Tosoh Corporation make). .

Separately, 17 parts of a compound (3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate) in which W is a group represented by the formula (v) is dissolved in 30 parts of diethylene glycol methyl ethyl ether, and dilauric acid dilaurate is dissolved. -After adding 0.03 part of n-butyltin (IV) and 0.1 part of 4-methoxyphenol, it stirred at 5 degreeC for 30 minutes. Thereafter, 10 parts of 2-hydroxyethyl acrylate was added dropwise, and the mixture was held at 5 ° C. for 1 hour under non-stirring, and then reacted with stirring at room temperature for 2 hours, whereby a free isocyanate group-containing unsaturated compound (β-1 ) Was obtained.
Next, the solution of the free isocyanate group-containing unsaturated compound (β-1) was added dropwise to the copolymer (α-1) solution over 1 hour at 30 ° C. with stirring, and then at the same temperature. By reacting with stirring for 3 hours, a solution of [A] polymer having a solid concentration of 31.5% was obtained. This [A] polymer is referred to as “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 30 parts of glycidyl methacrylate. , 27 parts of tricyclo [5.2.1.02,6] decan-8-yl methacrylate, 5 parts of styrene, 10 parts of 2-hydroxyethyl methacrylate and 10 parts of tetrahydrofuran-2-yl methacrylate are charged with nitrogen. After the substitution, 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 (α) solution having a solid content concentration of 29.0% was obtained. Obtained. This copolymer (α) is referred to as “copolymer (α-2)”.
It was 11,000 when Mw was measured about the obtained copolymer ((alpha) -2) using GPC (gel permeation chromatography) HLC-8020.
Next, the solution of the free isocyanate group-containing unsaturated compound (β-1) obtained in the same manner as in Synthesis Example 1 was added to the solution of the copolymer (α-2) at 30 ° C. over 1 hour while stirring. Then, the mixture was reacted while stirring at the same temperature for 3 hours to obtain a solution of [A] polymer having a solid content concentration of 31.0%. This [A] polymer is referred to as “polymer (A-2)”.

Synthesis example 3
13 parts of 2,5-bis (isocyanatomethyl) bicyclo [2.2.1] heptane is dissolved in 30 parts of diethylene glycol methyl ethyl ether, and 0.03 part of di-n-butyltin dilaurate (IV) is added. -After adding 0.1 part of methoxyphenol, it stirred at 5 degreeC for 30 minutes. Thereafter, 10 parts of 2-hydroxyethyl acrylate was added dropwise, and the mixture was held at 5 ° C. for 1 hour under non-stirring, and then reacted with stirring at room temperature for 2 hours, whereby a free isocyanate group-containing unsaturated compound (β-2 ) Was obtained.
Next, to the solution of the copolymer (α-1) obtained in the same manner as in Synthesis Example 1, the solution of the free isocyanate group-containing unsaturated compound (β-2) was stirred at 30 ° C. for 1 hour. Then, the mixture was reacted while stirring at the same temperature for 3 hours to obtain a solution of [A] polymer having a solid content concentration of 32.0%. This [A] polymer is referred to as “polymer (A-3)”.

Synthesis example 4
While stirring the solution of the free isocyanate group-containing unsaturated compound (β-2) obtained in the same manner as in Synthesis Example 3, the copolymer (α-2) solution obtained in the same manner as in Synthesis Example 2 was used. After dripping at 1 degreeC over 1 hour, it was made to react, stirring at the same temperature for 3 hours, and the solution of [A] polymer of 32.0% of solid content concentration was obtained. This [A] polymer is referred to as “polymer (A-4)”.

Synthesis example 5
After dissolving 13 parts of 2,6-hexamethylene diisocyanate in 200 parts of diethylene glycol methyl ethyl ether and adding 0.03 part of di-n-butyltin (IV) dilaurate and 0.1 part of 4-methoxyphenol, The mixture was stirred at 5 ° C for 30 minutes. Thereafter, 85 parts of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (trade name KAYARAD DPHA, manufactured by Nippon Kayaku Co., Ltd.) was added dropwise, and the mixture was kept at 5 ° C. for 1 hour under non-stirring. By reacting with stirring for a period of time, a solution of a free isocyanate group-containing unsaturated compound (β-3) was obtained.
Next, the solution of the free isocyanate group-containing unsaturated compound (β-3) was stirred for 1 hour at 30 ° C. while stirring the solution of the copolymer (α-2) obtained in the same manner as in Synthesis Example 2. Then, the mixture was reacted at the same temperature with stirring for 3 hours to obtain a solution of [A] polymer having a solid content concentration of 30.3%. This [A] polymer is referred to as “polymer (A-5)”.

Example 1
Preparation of Composition Solution As [A] component, 100 parts of polymer (A-1) solution obtained in Synthesis Example 1 as polymer (A-1), and as [B] component, dipentaerystol hexaacrylate ( Product name KAYARAD DPHA, 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 of surfactant FTX-218 as a surfactant, 0.5 parts of 4-methoxyphenol as a storage stabilizer, and propylene glycol monomethyl ether so that the solid content concentration is 30% After dissolving in acetate, the solution was filtered through a Millipore filter having a pore size of 0.5 μm to prepare a composition solution (S-1).
Formation of Spacer After applying the composition solution (S-1) on an alkali-free glass substrate using a spinner, it was pre-baked on a hot plate at 80 ° C. for 3 minutes to form a film having a thickness of 4.0 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 5.

Evaluation-sensitivity-
When the spacer was formed in the same manner as the spacer formation 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) was 90% or more. Sensitivity was defined as the minimum exposure amount. When this exposure amount is 1,200 J / m ² or less, it can be said that the sensitivity is good.

-Resolution-
In the same manner as the spacer formation except that the exposure amount was changed, when the spacer was formed, the evaluation was performed based on the minimum pattern size resolved with the minimum exposure amount at which the residual film ratio after development was 90% or more. .

-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 C 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, in the case of an inversely tapered shape (inverted triangular shape with a cross-sectional shape whose film surface side is longer than the side on the substrate side), the possibility of the spacer being peeled off during the rubbing process is increased. Therefore, the cross-sectional shape was regarded as defective.

-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, both loading speed and unloading speed are 2.6 mN / sec, and 50 mN. The load until the load was held for 5 seconds and then unloaded, and a load-deformation curve and a load-deformation curve during loading were prepared. At this time, as shown in FIG. 4, 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 unloading. The elastic recovery rate was calculated by the following formula, with the difference between L2 and L2.
Elastic recovery rate (%) = L2 × 100 / L1

-Rubbing resistance-
After applying AL3046 (trade name, manufactured by JSR Co., Ltd.) as a liquid crystal aligning agent to the substrate on which the spacer is formed, using a printing machine for applying a liquid crystal alignment film, the substrate is dried at 180 ° C. for 1 hour, and the film thickness is 0.05 μm. A liquid crystal aligning agent film was formed.
Thereafter, the coating film was rubbed 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 scraping or peeling of the spacer was evaluated.

-Adhesion-
After forming a cured film in the same manner as in the formation of the spacer except that no photomask was used, among the adhesion tests of JIS K-5400 (1900) 8.5, the grid of 8.5-2 The tape method was used for evaluation. At this time, the number of remaining grids out of 100 grids is shown in Tables 5-8.

-Heat resistance-
A cured film was formed in the same manner as in 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. Evaluation was made by the following film thickness × 100 / initial film thickness).

Examples 2-48 and Comparative Examples 1-4
[A] component or copolymer, [B] component and [C] component shown in Tables 1 to 4 are used as adhesion assistants, 5 parts of γ-glycidoxypropyltrimethoxysilane, and FTX- 218 is mixed with 0.5 part of 4-methoxyphenol as a storage stabilizer, dissolved in propylene glycol monomethyl ether acetate so that the solid content concentration becomes 30%, and then millipore having a pore size of 0.5 μm. It filtered with the filter and the composition solution was prepared. Thereafter, evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Tables 5-8.
In the case where the cross-sectional shape of the spacer is an inversely tapered shape (C), the adhesion with the substrate is lowered and it becomes difficult to measure the elastic recovery rate. Therefore, Comparative Example 1 in Table 8 shows the evaluation result of the elastic recovery rate. Absent.

  In Tables 1-4, each component other than [A] component and a copolymer 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 KAYARAD DPHA-40H manufactured by Nippon Kayaku Co., Ltd.)
[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 E-4: 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole,

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 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 loading and unloading in evaluation of an elastic recovery factor.

Claims (9)

A copolymer (α) of (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride, (a2) a hydroxyl group-containing unsaturated compound, and (a3) another unsaturated compound, (b1) the following formula ( [A] a polymer obtained by reacting the free isocyanate group-containing unsaturated compound (β) obtained by reacting the diisocyanate compound represented by 1) with the (b2) hydroxyl group-containing polymerizable unsaturated compound The radiation sensitive resin composition characterized by the above-mentioned.
[In Formula (1), W shows the bivalent group represented by following formula (i)-(ix).
(However, n is an integer of 1-12.)
] The radiation-sensitive resin composition according to claim 1, wherein the diisocyanate compound is a compound in which W is represented by the formula (ix) in the formula (1). A radiation-sensitive resin composition comprising the [A] polymer according to claim 1, [B] a polymerizable unsaturated compound, and [C] a radiation-sensitive polymerization initiator. [C] The radiation-sensitive resin composition according to claim 3, wherein at least a part of the radiation-sensitive polymerization initiator is an o-acyloxime-type photopolymerization initiator. The radiation-sensitive resin composition according to any one of claims 1 to 4, which is used for forming a spacer. A method for forming a spacer for a liquid crystal display element, comprising the following steps in the order described below.
(A) forming a film of the radiation sensitive resin composition according to claim 3 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. A spacer formed by the method of claim 6. The spacer according to claim 7, wherein the elastic recovery rate is 80% or more. A liquid crystal display device comprising the spacer according to claim 6.