JP4826803B2 - Radiation-sensitive resin composition, spacer for liquid crystal display element and production method thereof - Google Patents

Description

  The present invention relates to a radiation-sensitive resin composition containing a side chain unsaturated polymer that is extremely suitable for forming a spacer in a liquid crystal display device, a spacer, a method for forming the same, and a liquid crystal display device.

Conventionally, spacers such as glass beads and plastic beads having a predetermined particle diameter have been used for liquid crystal display elements in order to keep the distance (cell gap) between two substrates constant. Since these spacers are randomly distributed on a transparent substrate such as a glass substrate, if there is a spacer in the pixel formation region, the occurrence of a spacer reflection phenomenon or the scattering of incident light causes contrast as a liquid crystal display element. There was a problem that decreased.
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 1,500 × 1,800 mm, and further about 1,870 × 2,200 mm) from the viewpoint of increasing the area of the liquid crystal display element and improving productivity. Yes. However, with the conventional substrate size, the substrate size is smaller than the mask size, so it was possible to cope with the batch exposure method. However, with a large substrate, it is almost impossible to produce a mask size comparable to this substrate size. It is possible, and it is difficult to cope with the batch exposure method.
Therefore, a step exposure method has been proposed as an exposure method that can be applied to a large substrate. However, in the step exposure method, a single substrate is exposed several times, and each exposure requires time for alignment and step movement. Therefore, the throughput is reduced as compared with the batch exposure method. Therefore, there is a demand for high sensitivity for the radiation-sensitive resin composition.

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

  In Patent Document 1, Patent Document 2 and Patent Document 3, a photopolymerizable functional group obtained by reacting a copolymer resin having a hydroxyl group with a (meth) acryloyloxyalkyl isocyanate compound in a photosensitive resin composition is a constituent unit. It is said that the use of the copolymerizable resin can improve the performance as a spacer and protective film such as high sensitivity and chemical resistance. Novolak type epoxy having two or more epoxy groups in the molecule for the purpose of improving the heat resistance of spacers and protective films, adhesion to substrates, and chemical resistance, especially for the alignment film stripping solution and alkaline aqueous solution. Resin is used. However, there is a concern that the addition of this epoxy resin may lower the solubility of the photosensitive resin composition in the developer.

Furthermore, since the molecular structure of the acrylic resin type and the novolac type epoxy resin are greatly different from each other, the compatibility between the resins is low, and uneven surface roughness may occur on the surface of the formed spacer. When uneven surface roughness occurs on the spacer surface, it becomes difficult to strictly control the cell gap, and as a result, the quality of the liquid crystal display element may be deteriorated. In the resin composition, the addition of a novolac-type epoxy resin compound can improve adhesion to the substrate and chemical resistance (alignment film peeling solution resistance), but there is concern about solubility in the developer and rough surface of the pattern. Is done.
JP 2000-105456 A JP 2000-171804 A JP 2000-298339 A

Therefore, the object of the present invention is high sensitivity, a sufficient spacer shape can be obtained even with an exposure dose of 1,000 J / m ² or less, and excellent in elastic recovery, rubbing resistance, adhesion to a transparent substrate, heat resistance, etc. Another object of the present invention is to provide a radiation-sensitive resin composition that is excellent in developability and that can form a spacer for a liquid crystal display device having no uneven surface on the pattern surface.

  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 device including the same.

  Still another object of the present invention is to provide a method for forming the above 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 above objects and advantages of the present invention are, firstly,
[A1] (a1) a copolymer of at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, and (a2) an unsaturated compound containing one or more hydroxyl groups in one molecule. A polymer obtained by reacting an isocyanate group-containing unsaturated compound represented by the following formula (1), and

(In the formula, R ¹ is a hydrogen atom or a methyl group, and n is an integer of 1 to 12.)
[A2] containing (a1) at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, and (a3) a copolymer of an unsaturated compound having an oxiranyl group or an oxetanyl group. This is achieved by the featured radiation-sensitive resin composition.
Here, (a2) component of the [A1] is Ru unsaturated compound der having a hydroxyl group represented by the following formula (2).

(In the formula, R ² is a hydrogen atom or a methyl group, l is an integer of 1 to 12, and m is an integer of 1 to 6.)

According to the present invention, the above objects and advantages of the present invention are as follows. Secondly, the radiation-sensitive resin composition further contains [B] a polymerizable unsaturated compound and [C] a radiation-sensitive polymerization initiator. This is preferably achieved by a radiation-sensitive resin composition (hereinafter referred to as “a radiation-sensitive resin composition for a liquid crystal display element spacer”) used for forming a device spacer.

According to the present invention, the above objects and advantages of the present invention are thirdly:
This is achieved by a spacer for a liquid crystal display element formed from each of the radiation sensitive resin compositions.

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

According to the present invention, the above objects and advantages of the present invention are fifthly:
This is achieved by a liquid crystal display element comprising the liquid crystal display element spacer.

The radiation-sensitive resin composition of the present invention has high sensitivity and high resolution, and a sufficient pattern shape can be obtained even at an exposure amount of 1,000 J / m ² or less, and has excellent developability, elastic recovery, rubbing resistance, and transparency. Excellent adhesion to the substrate, heat resistance, etc. In addition, it is possible to form spacers for liquid crystal display elements that do not have uneven surface roughness on the resulting pattern surface, which can cause yellowing or deformation of the resin substrate Absent.
The liquid crystal display element of the present invention has excellent performance such as sensitivity, developability, elastic recovery, rubbing resistance, adhesion to a transparent substrate, heat resistance, and the like, and includes a spacer having no uneven surface on the pattern surface. Therefore, high reliability can be realized over a long period of time.

  Hereinafter, the present invention will be described in detail.

-[A] polymer-
The composition of the present invention contains [A1] (a1) at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, and (a2) one or more hydroxyl groups in one molecule. An isocyanate compound represented by the above formula (1) (hereinafter referred to as “unsaturated isocyanate compound (1)”) is added to a copolymer of unsaturated compounds (hereinafter referred to as “copolymer [α]”). A polymer obtained by reaction (hereinafter referred to as “[A] polymer”);
[A2] (a1) A copolymer of at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic anhydride and (a3) an unsaturated compound having an oxiranyl group or an oxetanyl group (hereinafter referred to as “copolymer”) Combined [β] ”).

Among the components constituting the copolymer [α] and the copolymer [β], (a1) unsaturated carboxylic acid and unsaturated carboxylic acid anhydride (hereinafter collectively referred to as “(a1) unsaturated carboxylic acid” For example, it is referred to as a "system compound".
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, copolymerization reactivity, solubility of the resulting polymer and copolymer in an alkaline developer, and easy availability, acrylic acid, methacrylic acid, anhydrous Maleic acid and the like are preferred.
In the copolymer [α] and the copolymer [β], the (a1) unsaturated carboxylic acid compound can be used alone or in admixture of two or more.
In the copolymer [α] and the copolymer [β], 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. Particularly preferably, it is 15 to 30% by weight. (A1) If 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 unsaturated isocyanate compound (1) in the alkaline developer tends to decrease. On the other hand, if it exceeds 50% by weight, the solubility of the polymer in an alkaline developer may become too high.

Further, (a2) an unsaturated compound having a hydroxyl group represented by the above following formula of component (2), points and to improve the developing property, particularly desirable from the viewpoint of compression performance improvement of the resulting spacer.
Specific examples thereof include acrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester, acrylic acid 3- (6-hydroxyhexanoyloxy) propyl ester, acrylic acid 4- (6-hydroxyhexanoyloxy) butyl ester. Acrylic acid (6-hydroxyhexanoyloxy) alkyl esters such as acrylic acid 5- (6-hydroxyhexanoyloxy) pentyl ester, acrylic acid 6- (6-hydroxyhexanoyloxy) hexyl ester;
Methacrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester, methacrylic acid 3- (6-hydroxyhexanoyloxy) propyl ester, methacrylic acid 4- (6-hydroxyhexanoyloxy) butyl ester, methacrylic acid 5- ( Methacrylic acid (6-hydroxyhexanoyloxy) alkyl esters such as 6-hydroxyethylhexanoyloxy) pentyl ester, methacrylic acid 6- (6-hydroxyhexanoyloxy) hexyl ester;
Among these, acrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester and methacrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester are desirable, and methacrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester is preferable. As a commercial item of the mixture of ester and methacrylic acid 2-hydroxyethyl ester, PLACEL FM1D, FM2D (manufactured by Daicel Chemical Industries, Ltd.) and the like can be given as trade names.

In the copolymer [α], (a2) unsaturated compounds containing one or more hydroxyl groups in one molecule can be used alone or in admixture of two or more.
In the copolymer [α], (a2) the content of repeating units derived from an unsaturated compound containing one or more hydroxyl groups in one molecule is preferably 1 to 50% by weight, more preferably 3 to 40%. % By weight, particularly preferably 5 to 30% by weight. (A2) When the content of the repeating unit derived from the unsaturated compound containing one or more hydroxyl groups in one molecule is less than 1% by weight, the introduction rate of the unsaturated isocyanate compound (1) into the polymer is decreased. Thus, the sensitivity tends to decrease. On the other hand, if it exceeds 50% by weight, the storage stability of the polymer obtained by the reaction with the unsaturated isocyanate compound (1) tends to decrease.

Examples of the unsaturated compound having an oxiranyl group or oxetanyl group (a3) in the copolymer [β] include glycidyl acrylate, 2-methylglycidyl acrylate, 4-hydroxybutyl acrylate glycidyl ether, and acrylic acid 3 , 4-epoxybutyl, acrylic acid epoxy (cyclo) alkyl esters such as 6,7-epoxyheptyl acrylate, 3,4-epoxycyclohexyl acrylate;
Methacrylic acid such as glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate Acid epoxy (cyclo) alkyl esters;
α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylate glycidyl, α-ethyl acrylate 6,7-epoxyheptyl, α-ethyl acrylate 3,4-epoxycyclohexyl, etc. Other α-alkyl acrylic acid epoxy (cyclo) alkyl esters;
glycidyl ethers such as o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether;
3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, 3- (methacryloyloxymethyl) -2-methyloxetane, 3- (methacryloyloxymethyl) -2-trifluoromethyloxetane, 3- (methacryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (methacryloyloxymethyl) -2-phenyloxetane, 3- (methacryloyloxymethyl) -2,2-difluorooxetane, 3- (methacryloyloxymethyl) ) -2,2,4-trifluorooxetane, 3- (methacryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -3 -Ethyloxy Tan, 2-ethyl-3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -2-trifluoromethyloxetane, 3- (methacryloyloxyethyl) -2-pentafluoroethyloxetane, 3- (methacryloyloxy) Ethyl) -2-phenyloxetane, 2,2-difluoro-3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -2,2,4-trifluorooxetane, 3- (methacryloyloxyethyl) -2 Methacrylic acid esters such as 1,2,4,4-tetrafluorooxetane;
3- (acryloyloxymethyl) oxetane, 3- (acryloyloxymethyl) -3-ethyloxetane, 3- (acryloyloxymethyl) -2-methyloxetane, 3- (acryloyloxymethyl) -2-trifluoromethyloxetane, 3- (acryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (acryloyloxymethyl) -2-phenyloxetane, 3- (acryloyloxymethyl) -2,2-difluorooxetane, 3- (acryloyloxymethyl) ) -2,2,4-trifluorooxetane, 3- (acryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -3 -Ethyloxetane, 2-ethyl-3 (Acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -2-trifluoromethyloxetane, 3- (acryloyloxyethyl) -2-pentafluoroethyloxetane, 3- (acryloyloxyethyl) -2-phenyloxetane, 2,2-difluoro-3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -2,2,4-trifluorooxetane, 3- (acryloyloxyethyl) -2,2,4,4-tetra Acrylic esters such as fluorooxetane are mentioned.

  Among these, glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, 3-methyl-3- (meth) acryloxymethyloxetane, 3-ethyl-3- (meth) Acryloxymethyl oxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, and the like are desirable from the viewpoint of polymerizability.

In the copolymer [β], (a3) can be used alone or in admixture of two or more.
In the copolymer [β], the content of the repeating unit derived from (a3) is preferably 0.5 to 70% by weight, more preferably 1 to 60% by weight, and particularly preferably 3 to 50% by weight. . If the content of the repeating unit derived from (a3) is less than 0.5% by weight, the heat resistance of the resulting copolymer tends to be reduced, whereas if it exceeds 70% by weight, the storage stability of the copolymer is decreased. Tends to decrease.

In the copolymer [α] and the copolymer [β], unsaturated compounds other than (a1), (a2) and (a3) can be used as a component of the copolymer. Specific examples thereof include alkyl acrylates such as methyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, sec-butyl acrylate, and 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 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 dialkyl esters such as diethyl maleate, diethyl fumarate, diethyl itaconate;
Acrylic acid ester having an oxygen-containing hetero 5-membered ring or an oxygen-containing hetero 6-membered ring such as tetrahydrofuran-2-yl acrylate, tetrahydropyran-2-yl acrylate, 2-methyltetrahydropyran-2-yl acrylate;
Methacrylic acid ester having an oxygen-containing hetero 5-membered ring or an oxygen-containing hetero 6-membered ring such as tetrahydrofuran-2-yl methacrylate, tetrahydropyran-2-yl methacrylate, 2-methyltetrahydropyran-2-yl methacrylate;
Vinyl aromatic compounds such as styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene;
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, from the viewpoint of copolymerization reactivity, n-butyl methacrylate, 2-methylglycidyl methacrylate, benzyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate. , Styrene, p-methoxystyrene, tetrahydrofuran-2-yl methacrylate, 1,3-butadiene and the like are preferable.

In the copolymer [α] and the copolymer [β], unsaturated compounds other than (a1), (a2) and (a3) can be used alone or in admixture of two or more.
In the copolymer [α] and the copolymer [β], the content of repeating units derived from unsaturated compounds other than (a1), (a2) and (a3) is preferably 10 to 70% by weight, Preferably it is 20-50 weight%, Most preferably, it is 30-50 weight%. If the content of this repeating unit is less than 10% by weight, the molecular weight of the copolymer tends to decrease. On the other hand, if it exceeds 70% by weight, the effects of the components (a1), (a2) and (a3) decrease. .
Copolymer [α] and copolymer [β] can be produced by polymerization in a suitable 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 propionate such as propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether propionate, propylene glycol mono-n-propyl ether propionate, propylene glycol mono-n-butyl ether propionate;
Aromatic hydrocarbons such as toluene and xylene;
Ketones such as methyl ethyl ketone, 2-pentanone, 3-pentanone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone;
Methyl 2-methoxypropionate, ethyl 2-methoxypropionate, n-propyl 2-methoxypropionate, n-butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, 2-ethoxypropion N-propyl acid, n-butyl 2-ethoxypropionate, methyl 2-n-propoxypropionate, ethyl 2-n-propoxypropionate, n-propyl 2-n-propoxypropionate, 2-n-propoxypropionic acid n-butyl, methyl 2-n-butoxypropionate, ethyl 2-n-butoxypropionate, n-propyl 2-n-butoxypropionate, n-butyl 2-n-butoxypropionate, methyl 3-methoxypropionate , Ethyl 3-methoxypropionate, 3-methoxy N-propyl propionate, n-butyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, n-propyl 3-ethoxypropionate, n-butyl 3-ethoxypropionate, 3-n -Methyl propoxypropionate, ethyl 3-n-propoxypropionate, n-propyl 3-n-propoxypropionate, n-butyl 3-n-propoxypropionate, methyl 3-n-butoxypropionate, 3-n- Alkyl alkoxypropionates such as ethyl butoxypropionate, n-propyl 3-n-butoxypropionate, n-butyl 3-n-butoxypropionate,
Methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl hydroxyacetate, ethyl hydroxyacetate, n-propyl hydroxyacetate, n-butyl hydroxyacetate, 4-methoxybutyl acetate, 3-methoxybutyl acetate, acetic acid 2 -Methoxybutyl, 3-ethoxybutyl acetate, 3-proxybutyl acetate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, methyl 2-hydroxy-2-methylpropionate, 2-hydroxy-2-methyl Ethyl propionate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, n-propyl 3-hydroxypropionate, n-butyl 3-hydroxypropionate, methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, Ethoxy methoxyacetate, methoxyacetic acid -Propyl, n-butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, n-propyl ethoxyacetate, n-butyl ethoxyacetate, methyl n-propoxyacetate, ethyl n-propoxyacetate, n-propyloxyacetate n-propyl, n Examples include other esters such as n-butyl propoxyacetate, methyl n-butoxyacetate, ethyl n-butoxyacetate, n-propyl n-butoxyacetate, n-butyl n-butoxyacetate, and the like.

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

Moreover, when using a peroxide as a radical polymerization initiator, it is good also as a redox type initiator using it together with a reducing agent.
These radical polymerization initiators can be used alone or in admixture of two or more.
The copolymer [α] and the copolymer [β] thus obtained can be used in the production of the [A] polymer as they are in solution, or once separated from the solution, You may use for manufacture.
The polystyrene-converted weight average molecular weight (hereinafter referred to as “Mw”) of the copolymer [α] and the copolymer [β] by gel permeation chromatography (GPC) is preferably 2,000 to 100,000, more preferably. Is 5,000 to 50,000. If the Mw is less than 2,000, the resulting film may be deteriorated in alkali developability, residual film ratio, or the like, or may be damaged in pattern shape, heat resistance, or the like. , There is a possibility that the resolution is lowered or the pattern shape is damaged.

The [A] polymer in the present invention can be obtained by reacting the unsaturated isocyanate compound (1) with the copolymer [α].
As unsaturated isocyanate compound (1), for example,
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, 2-methacryloyloxyethyl isocyanate, 4-methacryloyloxybutyl isocyanate and the like are preferable 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 using a catalyst such as dilauric acid di-n-butyltin (IV) or a polymerization inhibitor such as p-methoxyphenol. It can be carried out by adding the unsaturated isocyanate compound (1) to the copolymer [α] solution containing the solution 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 as follows: (a2) in the copolymer [α], the hydroxyl group of the unsaturated compound containing one or more hydroxyl groups in one molecule Preferably it is 0.1-95 mol% with respect to 1 equivalent, More preferably, it is 10-80 mol%, Most preferably, it is 15-75 mol%. When the amount of the unsaturated isocyanate compound (1) used is less than 0.1 mol%, the effect of improving the sensitivity, heat resistance and elasticity is small. On the other hand, when the amount exceeds 95 mol%, an 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 and a polymerizable unsaturated bond, has an appropriate solubility in an alkali developer, and is easily cured by exposure and heating. Furthermore, by using together with an acrylic copolymer [β] having an epoxy group, it is compatible with the [A] polymer without phase separation, and without causing pattern surface roughness. It is possible to improve the strength of the spacer while having excellent developability. [A] A radiation-sensitive resin composition containing a polymer and a copolymer [β] can easily form a spacer having a predetermined shape without developing residue and film loss during development.
[A] The amount of the copolymer [β] used with respect to 100 parts by weight of the polymer is preferably 0.5 to 50 parts by weight, more preferably 1 to 40 parts by weight, and particularly preferably 3 to 30 parts by weight. Parts by weight. When the amount of the copolymer [β] used is less than 0.5 parts by weight, the effect of improving the strength and heat resistance of the spacer is small. On the other hand, when it exceeds 50 parts by weight, the storage stability of the radiation-sensitive resin composition is lowered. There is a tendency to make it.

-Radiosensitive resin composition-
The radiation-sensitive resin composition of the present invention contains a [A] polymer and a copolymer [β] as described above, preferably [B] a polymerizable unsaturated compound and [C] initiation of radiation-sensitive polymerization. An agent can be contained.

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

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

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

  Furthermore, as the tri- 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, 9 or more functionalities As (meth) acrylic acid esters, linear alkylene groups and alicyclic structures And a compound having two or more isocyanate groups and a compound having one or more hydroxyl groups in the molecule and having three, four or five acryloyloxy groups and / or methacryloyloxy groups The polyfunctional urethane acrylate type compound etc. which are obtained by making it react with can be mentioned.

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

Among these monofunctional, bifunctional, or trifunctional or higher (meth) acrylic acid esters, trifunctional or higher functional (meth) acrylic acid esters are more preferable, and in particular, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol. Tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, and commercial products containing polyfunctional urethane acrylate compounds are preferred.
The monofunctional, bifunctional, or trifunctional or higher (meth) acrylic acid esters can be used alone or in admixture of two or more.
In the radiation sensitive resin composition of the present invention, the amount of the [B] polymerizable unsaturated compound used is preferably 1 to 120 parts by weight, more preferably 3 to 100 parts per 100 parts by weight of the [A] polymer. Parts by weight. [B] If the amount of the polymerizable unsaturated compound used is less than 1 part by weight, there is a possibility that a developing residue may be generated during development. On the other hand, if it exceeds 120 parts by weight, the adhesion of the resulting spacer tends to decrease.

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

  As the O-acyloxime compound, 9. H. A carbazole-based O-acyloxime polymerization initiator is preferred. For example, 1- [9-ethyl-6-benzoyl-9. H. -Carbazol-3-yl] -nonane-1,2-nonane-2-oxime-O-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, 1- [9-ethyl-6- (2-methyl-4-tetrahydropyranylmethoxybenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate, 1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylmethoxybenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate, ethanone-1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylmethoxybenzoyl) -9. H. -Carbazole-3-yl] -1- (O-acetyloxime), ethanone-1- [9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl } -9. H. -Carbazol-3-yl] -1- (O-acetyloxime) and the like.

  Of these O-acyloxime compounds, 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate, 1- [9-ethyl-6- (2-methyl-4-tetrahydropyranylmethoxybenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate, ethanone-1- [9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxy Benzoyl} -9. H. -Carbazol-3-yl] -1- (O-acetyloxime) is preferred.

The O-acyloxime compounds can be used alone or in admixture of two or more. In the present invention, the use of an O-acyloxime compound makes it possible to obtain a spacer having sufficient sensitivity and adhesion even with an exposure amount of 1,000 J / m ² or less.
Examples of the acetophenone compound include an α-hydroxyketone compound and an α-aminoketone compound.

  Examples of the α-hydroxyketone compound include 1-phenyl-2-hydroxy-2-methylpropan-1-one, 1- (4-i-propylphenyl) -2-hydroxy-2-methylpropane-1 -One, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenylketone and the like. Examples of the α-aminoketone compound include 2 -Methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2- (4- And methylbenzoyl) -2- (dimethylamino) -1- (4-morpholinophenyl) -butan-1-one. wear. 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, the sensitivity, spacer shape and compressive strength can be further improved by using an acetophenone compound in combination.

  Examples of the biimidazole compound include 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetrakis (4-ethoxycarbonylphenyl) -1,2′-biimidazole. 2,2′-bis (2-bromophenyl) -4,4 ′, 5,5′-tetrakis (4-ethoxycarbonylphenyl) -1,2′-biimidazole, 2,2′-bis (2- Chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (2,4-dichlorophenyl) -4,4 ′, 5,5′-tetraphenyl -1,2'-biimidazole, 2,2'-bis (2,4,6-trichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole, 2,2 '-Bis (2-bromophenyl)- , 4 ′, 5,5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (2,4-dibromophenyl) -4,4 ′, 5,5′-tetraphenyl-1, 2'-biimidazole, 2,2'-bis (2,4,6-tribromophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole and the like can be mentioned. .

  Among these biimidazole compounds, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (2 , 4-dichlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (2,4,6-trichlorophenyl) -4,4 ′, 5 , 5′-tetraphenyl-1,2′-biimidazole and the like are preferable, and in particular, 2,2′-bis (2,4-dichlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2 ′. -Biimidazole is preferred.

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

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

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

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

  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.

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.

-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, polyoxy Polyoxyethylene aryl ethers such as ethylene n-nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate, and commercial products, For example, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 57, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.).

The surfactants can be used alone or in admixture of two or more.
The 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 between the spacer and the substrate, and a functional silane coupling agent is preferable.

Examples of the functional silane coupling agent include compounds having a reactive functional group such as a carboxyl group, a methacryloyl group, a vinyl group, an isocyanate group, and an epoxy group, and more specifically, trimethoxysilyl. Benzoic acid, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ) Ethyltrimethoxysilane and the like.
These adhesion assistants can be used alone or in admixture of two or more.
The blending amount of the adhesion assistant is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, with respect to 100 parts by weight of the [A] 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 pattern shape may be impaired.

Examples of the heat resistance improver include N- (alkoxymethyl) glycoluril compounds and N- (alkoxymethyl) melamine compounds.
Examples of the N- (alkoxymethyl) glycoluril compound include N, N, N ′, N′-tetra (methoxymethyl) glycoluril, N, N, N ′, N′-tetra (ethoxymethyl) glycoluril. N, N, N ′, N′-tetra (n-propoxymethyl) glycoluril, N, N, N ′, N′-tetra (i-propoxymethyl) glycoluril, N, N, N ′, N ′ -Tetra (n-butoxymethyl) glycoluril, N, N, N ′, N′-tetra (t-butoxymethyl) glycoluril and the like 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.
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 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 Alcohols, ethylene glycol monoalkyl ether acetate, diethylene glycol monoalkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether acetate, dipropylene glycol alkyl ether, alkoxypropionic acid Alkyl, acetate ester and the like are preferable, and in particular, benzyl alcohol, 2-phenylethanol, 3-phenyl-1-propanol, ethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ester. Ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, dipropylene glycol dimethyl ether, 3-methoxybutyl acetate, 2-methoxyethyl acetate and the like are preferable.
The said solvent can be used individually or in mixture of 2 or more types.

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

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

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

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

  Hereinafter, each of these steps will be described sequentially.

-(I) Process-
A transparent conductive film is formed on one surface of a transparent substrate, and a radiation-sensitive resin composition is applied onto the transparent conductive film, preferably as a composition solution, and then the coated surface is heated (prebaked) to form a coating film. Form.
Examples of the transparent substrate used for forming the spacer include a glass substrate and a resin substrate. More specifically, 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 method for applying the composition solution, for example, (1) a coating method and (2) a dry film method can be used as a method for forming a film of the photosensitive resin composition of the present invention.
As a coating method of the composition solution, for example, an appropriate method such as a spray method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, or an ink jet coating method can be employed. In particular, a spin coating method and a slit die coating method are preferable.

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

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

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

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

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

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

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

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

Synthesis example 1
A flask equipped with a condenser and a stirrer was charged with 5 parts of 2,2′-azobisisobutyronitrile and 250 parts of 3-methoxybutyl acetate, followed by 18 parts of methacrylic acid and tricyclomethacrylate [5.2. 1.0 ^2,6 ] 25 parts of decan-8-yl, 5 parts of styrene, 30 parts of methacrylic acid 2-hydroxyethyl ester and 22 parts of benzyl methacrylate, and after purging with nitrogen, the solution was stirred gently. Was increased to 80 ° C. and polymerization was carried out while maintaining this temperature for 5 hours to obtain a copolymer [α-1] solution having a solid content concentration of 28.8%.
For the obtained copolymer [α-1], Mw was 13,000 as measured using GPC (gel permeation chromatography) GPC-101 (trade name, manufactured by Showa Denko KK). .

Next, 14 parts of 2-methacryloyloxyethyl isocyanate (trade name Karenz MOI, manufactured by Showa Denko KK) and 0.1 part of 4-methoxyphenol were added to the copolymer [α-1] solution. The reaction was carried out by stirring at 1 ° C. for 1 hour and further at 60 ° C. for 2 hours. The progress of the reaction between the isocyanate group derived from 2-methacryloyloxyethyl isocyanate and the hydroxyl group of the copolymer [α-1] was confirmed by IR (infrared absorption) spectrum. In the IR spectrum of the polymer solution [α-1] after the reaction for 1 hour and the solution after the reaction at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours, 2270 cm derived from the isocyanate group of 2-methacryloyloxyethyl isocyanate ^It was confirmed that the peak near ⁻¹ was decreasing. A [A] polymer solution having a solid content concentration of 30.0% was obtained. Let this [A] polymer be a polymer (A-1).

Synthesis example 2
In the same manner as in Synthesis Example 1, 14 parts of 2-acryloyloxyethyl isocyanate (trade name Karenz AOI, Showa Denko KK) and 0.1 part of 4-methoxyphenol were added to the copolymer [α-1] solution. Then, the mixture was reacted by stirring at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours. A [A] polymer solution having a solid concentration of 30.5% was obtained. Let this [A] polymer be a polymer (A-2).

Synthesis example 3
To the copolymer [α-1] solution, 17 parts of 4-methacryloyloxybutyl isocyanate (trade name Karenz MOI-C4, manufactured by Showa Denko KK) and 4-methoxyphenol 0. After adding 1 part, it was made to react by stirring at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours. A [A] polymer solution having a solid concentration of 31.0% 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 2,2′-azobisisobutyronitrile, 125 parts 3-methoxybutyl acetate and 125 parts propylene glycol monomethyl ether acetate, followed by 18 parts methacrylic acid, Methacrylic acid tricyclo [5.2.1.0 ^2,6 ] decan-8-yl 25 parts and styrene 5 parts, butadiene 5 parts, methacrylic acid 2- (6-hydroxyhexanoyloxy) ethyl ester (trade name PLACEL FM1D After charging 25 parts (manufactured by Daicel Chemical Industries, Ltd.) and 22 parts of tetrahydrofuran-2-yl methacrylate and purging with nitrogen, the temperature of the solution was raised to 80 ° C. while gently stirring, and the temperature was increased to 5 ° C. A copolymer [α-2] solution having a solid content concentration of 29.1% was obtained by polymerization while maintaining the time. .
About the obtained copolymer [(alpha) -2], it was 18,000 when Mw was measured using GPC (gel permeation chromatography) GPC-101 (brand name, Showa Denko Co., Ltd. product). .

  Then, after adding 14 parts of 2-methacryloyloxyethyl isocyanate (trade name Karenz MOI, manufactured by Showa Denko KK) and 0.1 part of 4-methoxyphenol to the copolymer [α-2] solution, By stirring and reacting at 40 ° C. for 1 hour and further at 60 ° C. for 2 hours, an [A] polymer solution having a solid content concentration of 31.0% was obtained. This [A] polymer is referred to as a polymer (A-4).

Synthesis example 5
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 tricyclomethacrylate [5 .2.1.0 ^2,6 ] 34 parts of decan-8-yl, 5 parts of styrene, 5 parts of butadiene and 40 parts of glycidyl methacrylate were substituted with nitrogen, and the temperature of the solution was adjusted while gently stirring. The temperature was raised to 70 ° C., and this temperature was maintained for 5 hours for polymerization to obtain a copolymer [β-1] solution having a solid content concentration of 31.0%. About the obtained copolymer [(beta) -1], it was 11,000 when Mw was measured using GPC (gel permeation chromatography) GPC-101 (brand name, Showa Denko Co., Ltd. product). .

Synthesis Example 6
A flask equipped with a condenser and a stirrer was charged with 7 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts of propylene glycol monomethyl ether acetate. Subsequently, 19 parts of styrene, 38 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 13 parts of methacrylic acid and 30 parts of methyl glycidyl methacrylate were charged with nitrogen, and then gently stirred. Started. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 7 hours to obtain a polymer solution containing the copolymer [β-2]. The resulting polymer solution had a solid content concentration of 32.9%. About the obtained copolymer [(beta) -2], it was 12,000 when Mw was measured using GPC (gel permeation chromatography) GPC-101 (brand name, Showa Denko Co., Ltd. product). .

Synthesis example 7
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 tricyclomethacrylate [5 2.1.0 ^2,6 ] 34 parts of decan-8-yl, 5 parts of styrene, 5 parts of butadiene, 20 parts of 3,4-epoxycyclohexylmethyl methacrylate and 20 parts of tetrahydrofuran-2-yl methacrylate were charged. After purging with nitrogen, the temperature of the solution was raised to 70 ° C. while gently stirring, and polymerization was carried out while maintaining this temperature for 5 hours, whereby a copolymer [β-3 A solution was obtained. About the obtained copolymer [(beta) -3], it was 11,000 when Mw was measured using GPC (gel permeation chromatography) GPC-101 (brand name, Showa Denko Co., Ltd. product). .

Synthesis example 8
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 propylene glycol monomethyl ether acetate. Subsequently, 5 parts of styrene, 18 parts of methacrylic acid, 17 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 40 parts of 3- (methacryloyloxymethyl) -3-ethyloxetane, methacrylic acid After 20 parts of tetrahydrofuran-2-yl was charged and purged with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution containing a copolymer [β-4]. The solid content concentration of the obtained polymer solution was 29.0%, and the polymer weight average measured using GPC (gel permeation chromatography) GPC-101 (trade name, manufactured by Showa Denko KK). The molecular weight was 14,000.

Example 1 (Reference Example)
Preparation of Composition Solution As component [A], 100 parts of [A] polymer solution obtained in Synthesis Example 1 as polymer (A-1), copolymer [β-1] 10 obtained in Synthesis Example 5 Part, [B] component, dipentaerystol hexaacrylate (trade name KAYAARAD DPHA, Nippon Kayaku Co., Ltd.) 100 parts, [C] component, 1- [9-ethyl-6- (2-methyl) Benzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate (trade name IRGACURE OX02, manufactured by Ciba Specialty Chemicals), 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole 5 parts, 4,4'-bis (diethylamino) benzophenone 5 parts, 2-mercaptobenzothiazole 2.5 parts, γ- As a surfactant, 5 parts of glycidoxypropyltrimethoxysilane, 0.5 parts of FTX-218 (trade name, manufactured by Neos Co., Ltd.) and 0.5 parts of 4-methoxyphenol as a storage stabilizer were mixed. After dissolving in propylene glycol monomethyl ether acetate so that the solid content concentration becomes 30%, it is filtered through a Millipore filter with a pore size of 0.5 μm. To prepare a composition solution.

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

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

[C] component C-1: 1- [9-ethyl-6- (2-methylbenzoyl) -9. H. -Carbazol-3-yl] -ethane-1-one oxime-O-acetate (trade name IRGACURE OX02, manufactured by Ciba Specialty Chemicals)
C-2: Ethanone-1- [9-ethyl-6- [2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxybenzoyl] -9. H. -Carbazol-3-yl] -1- (O-acetyloxime) (N-1919 manufactured by ADEKA)
C-3: 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (trade name Irgacure 907, manufactured by Ciba Specialty Chemicals)
C-4: 2- (4-methylbenzoyl) -2- (dimethylamino) -1- (4-morpholinophenyl) -butan-1-one (trade name Irgacure 379, manufactured by Ciba Specialty Chemicals)
C-5: 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole C-6: 4,4′-bis (diethylamino) benzophenone C-7: 2-mercaptobenzothiazole

[D] Component D-1: Multifunctional novolak type epoxy resin (trade name, manufactured by Japan Epoxy Resin Co., Ltd., Epicoat 152)
In Examples 2 to 16 and Comparative Examples 1 to 5, composition solutions were prepared in the same manner as in Example 1. The results are shown in Table 1.
Moreover, Example 17 and Comparative Example 6 were carried out by the dry film method.
Examples 2 to 7 are reference examples.

Formation of Spacer In Examples 2 to 16 and Comparative Examples 1 to 5, the spacers were formed by applying to a substrate using a spinner. The details are shown below.
The composition solution was applied on a non-alkali glass substrate using a spinner, and then pre-baked on a hot plate at 100 ° C. for 3 minutes to form a film having a thickness of 3.5 μm.
Next, the obtained coating film was exposed through a photomask having a 10 μm square left pattern. Then, after developing with a 0.05 wt% potassium hydroxide aqueous solution at 25 ° C., the substrate was washed with pure water for 1 minute, and further heated in an oven at 230 ° C. for 30 minutes to form a spacer.
In Example 17 , spacers were formed by a dry film method. Details are shown below.

Example 17
A patterned thin film was formed and evaluated in the same manner as in Examples 1 to 14 except that a coating film was prepared from the liquid composition (S-17) of the radiation sensitive resin composition by the dry film method. Each component is shown in Table 1. The base film was peeled and removed before the exposure process. The evaluation results are shown in Table 2. Table 2 also shows the evaluation results of the following transferability.
Dry film preparation and transfer were performed as follows.
On a polyethylene terephthalate (PET) film having a thickness of 38 μm, a liquid composition (S-17) of a radiation sensitive resin composition was applied using an applicator, the coating film was heated at 100 ° C. for 5 minutes, and a thickness of 4 μm. A radiation-sensitive dry film (J-1) was prepared. Next, the radiation-sensitive transfer dry film is superposed on the surface of the glass substrate so that the surface of the radiation-sensitive transfer layer is in contact with the glass substrate, and the radiation-sensitive dry film (J-1) is laminated on the glass substrate by thermocompression bonding. Transcribed to.

-Evaluation of transferability of dry film to glass substrate-
When the radiation sensitive dry film is transferred onto the glass substrate by the thermocompression bonding method, the case where the dry film can be uniformly transferred onto the glass substrate is `` ○ '', and the dry film partially remains on the base film, The case where the dry film could not be uniformly transferred onto the glass substrate, such as when the dry film did not adhere to the glass substrate, was designated as “x”.

Comparative Example 6
In Example 17, it replaces with the liquid composition (S-17) of a radiation sensitive resin composition, and uses the liquid composition (s-6) of a radiation sensitive resin composition, It is the same as that of Example 17. After producing a radiation-sensitive dry film (J-2), a patterned thin film was formed and evaluated. Each component is shown in Table 1. The evaluation results are shown in Table 2. Table 2 also shows the evaluation results of transferability.

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

(1) Evaluation of development time The development time was 30, 40, 50, 60, 70, 80, 90, and 100 seconds. At each development time, the residue in the unexposed area was observed with an optical microscope. Table 2 shows the shortest development time when it was confirmed that there was no residue in the unexposed area at each development time. The shorter the development time, the better the developability.

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

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

(4) Evaluation of rubbing resistance AL3046 (trade name, manufactured by JSR Co., Ltd.) as a liquid crystal alignment 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.

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

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

(7) Evaluation of spacer pattern surface The surface of the obtained spacer was observed with a scanning electron microscope. The case where uneven surface roughness was observed was evaluated as x, and the case where it was not observed was evaluated as ◯. The results are shown in Table 2.

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

Claims (6)

[A1] (a1) a copolymer of at least one and (a2) unsaturated compound have a hydroxyl group represented by the following formula (2) selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic acid anhydride A polymer obtained by reacting an isocyanate group-containing unsaturated compound represented by the following formula (1):

(In the formula, R ² is a hydrogen atom or a methyl group, l is an integer of 1 to 12, and m is an integer of 1 to 6.)

(In the formula, R ¹ is a hydrogen atom or a methyl group, and n is an integer of 1 to 12.)
[A2] (a1) containing a copolymer of at least one selected from the group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride and (a3) an unsaturated compound having an oxiranyl group or an oxetanyl group. A radiation sensitive resin composition. [B] a polymerizable unsaturated compound and [C] a radiation-sensitive polymerization initiator further radiation-sensitive resin composition of claim 1 containing. The radiation sensitive resin composition of Claim 1 or 2 used for formation of the spacer for liquid crystal display elements. The spacer for liquid crystal display elements formed from the radiation sensitive resin composition of Claim 1 or 2 . A method for forming a spacer for a liquid crystal display element, comprising at least the following steps in the order described below.
(A) forming a film of the radiation sensitive resin composition according to claim 1 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 liquid crystal display device comprising the spacer according to claim 4 .

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