JPH11337949A - Photosensitive film for forming colored resin spacer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive film forming colored resin spacers which can easily form spacers having uniform film thickness and being excellent in mechanical strength, has no display unevenness owing to film thickness dispersion and can improve panel action reliability. SOLUTION: In the photosensitive film for forming colored resin spacers which is constituted by successively laminating (a) a base film, (b) a photosensitive resin layer having 3 to 10 μm film thickness and (c) a protective film in this order and can be developed by an alkali aq. soln., (b) the photosensitive resin layer contains (A) a high polymer compound having ethylenic unsaturated groups, (B) a photopolymerizable compound having at least two ethylenic unsaturated groups, (C) a photopolymerization initiator, (D) a black pigment and (E) a thermosetting resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a photosensitive film for forming a colored resin spacer.

[0002]

2. Description of the Related Art Liquid crystal televisions, computers for liquid crystal color display, and the like have been put into practical use. These liquid crystal display devices use a transparent substrate such as glass having a transparent electrode for 3 to 1 times.
With a gap of about 0 μm, a liquid crystal substance is sealed between the gaps, the liquid crystal substance is oriented by a voltage applied between the electrodes, and the light and shade are displayed. If the distance between the substrates is not accurately maintained, a difference occurs in the thickness of the liquid crystal layer, resulting in uneven color and abnormal contrast. Therefore, in order to accurately maintain the distance between the substrates, 3 to 1 called spacers are used.
Bead particles of 0 μm glass or synthetic resin are dispersed.

[0003] Spreading the spacers evenly,
It is quite difficult and leads to a decrease in yield to obtain a display device without color unevenness. Accordingly, Japanese Patent Application Laid-Open No. 4-223443
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-207, various devices are used for dispersion and introduction. As a fundamental solution to these problems, a method is known in which a black matrix is thickened between colored patterns of a color filter and used as a spacer (Japanese Patent Laid-Open No. 63-2370)
No. 32, JP-A-3-184022, JP-A-4
No. 122914) has been proposed, but it is difficult to control the thickness because it is formed by applying a black matrix. In addition, it has been considered that a spacer is formed by stacking colored patterns to secure the thickness (Japanese Patent Application Laid-Open No. 63-82405).

It has also been proposed that, when a colored pattern is produced, a colored pattern is formed on a black matrix by a coating method to form a spacer (Japanese Patent Application Laid-Open No. 63-163).
However, it is difficult to obtain a uniform film thickness as described above. Furthermore, in the resin described in the above-mentioned publication and Japanese Patent Application Laid-Open No. 7-325298, the black matrix and the colored pattern resin have insufficient mechanical strength. Has become. On the other hand, although the properties such as strength are sufficient in the conventionally-developed spacer by the bead dispersion and the film method, there is a problem that the operation reliability of the panel is insufficient.

[0005]

According to the first aspect of the present invention, a spacer having a uniform film thickness and excellent mechanical strength can be easily formed, there is no display unevenness due to a film thickness variation, and the panel operation reliability is improved. And a photosensitive film for forming a colored resin spacer.

[0006]

The present invention provides a photosensitive film comprising (a) a support film, (b) a photosensitive resin layer having a thickness of 3 to 10 μm, and (c) a protective film laminated in this order. b) the photosensitive resin layer is (A) a polymer compound having an ethylenically unsaturated group, (B) a photopolymerizable compound having at least two ethylenically unsaturated groups, (C)
The present invention relates to a photosensitive film for forming a colored resin spacer, which contains a photopolymerization initiator, (D) a black pigment, and (E) a thermosetting resin and can be developed with an alkaline aqueous solution.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The support film and the protective film used for the photosensitive film for forming a colored resin spacer in the present invention can be any known film without any particular limitation. Examples thereof include polyethylene terephthalate, polypropylene, Thickness 5 made of polyethylene etc.
A 100 μm polymer film is used.

In the present invention, the photosensitive resin layer of the photosensitive film for forming a colored resin spacer comprises (A) a polymer compound having a carboxyl group and an unsaturated double bond, and (B) at least two ethylenically unsaturated groups. (C) a photopolymerization initiator, (D) a black pigment, and (E) a thermosetting resin as essential components.

The ethylenically unsaturated group contained in the polymer compound (A) having an ethylenically unsaturated group includes groups having a carbon or carbon double bond such as an acryl group, an acryloyl group, a methacryloyl group, and a cinnamoyl group. No.

(A) The polymer compound having an ethylenically unsaturated group includes, for example, (i) a styrene monomer, (ii) an acrylic monomer, and (iii) a glycidyl group, a carboxyl group, a hydroxyl group, A styrene / acrylic prepolymer obtained by copolymerizing a monomer having a functional group such as an isocyanato group, and (iv) a monomer having a functional group capable of reacting with the functional group and a photopolymerizable unsaturated group Are reacted to introduce a photopolymerizable unsaturated group into the side chain. In a preferred embodiment of the polymer, (i) a styrene monomer 5 to 5
40% by weight, (ii) 10 to 70% by weight of an acrylic monomer, (iii) 25 to 4 of an acrylic monomer having a functional group
5 to 45 parts by weight of a monomer having a functional group capable of reacting with a functional group of the prepolymer and a photopolymerizable unsaturated group in 100 parts by weight of a styrene / acrylic prepolymer obtained by copolymerizing 5% by weight. And a polymer having a photopolymerizable unsaturated group introduced into the side chain.

The (i) styrene monomer includes, for example, α-methylstyrene, styrene, p-methylstyrene, p-chlorostyrene and the like. From the viewpoint of availability, styrene and p-methylstyrene are preferred. Styrene is preferred.
These styrene monomers are used alone or in combination of two or more.

The above (ii) acrylic monomers include, for example, methyl acrylate, ethyl acrylate, n-
Propyl acrylate, iso-propyl acrylate,
n-butyl acrylate, sec-butyl acrylate,
acrylates having an alkyl group having 1 to 8 carbon atoms, such as t-butyl acrylate and 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n
Methacrylate having an alkyl group having 1 to 8 carbon atoms, such as -propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, and 2-ethylhexyl methacrylate. The monomers are used alone or in combination of two or more.
Methyl methacrylate and ethyl acrylate are preferred in terms of availability and low cost.

Examples of the monomer (iii) having a functional group such as a glycidyl group, a carboxyl group, a hydroxyl group and an isocyanato group include glycidyl acrylate,
Glycidyl methacrylate, acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-isocyanatoethyl acrylate, 2-isocyanatoethyl methacrylate, and the like, and these may be used alone or in combination of two or more. Used. Acrylic acid and methacrylic acid are preferred in terms of availability and low cost.

In the above (iv) monomer having a functional group capable of reacting with the functional group of the prepolymer and a photopolymerizable unsaturated group, the photopolymerizable unsaturated group includes an allyl group, an acryloyl group, a methacryloyl group and the like. No. Specific examples of (iv) a monomer having a functional group capable of reacting with a functional group of the prepolymer and a photopolymerizable unsaturated group include the above-mentioned (iii) glycidyl group, carboxyl group, hydroxyl group, isocyanato group The same compounds as those exemplified for the acrylic monomer having a functional group such as Glycidyl methacrylate is preferred in terms of availability and low cost.

The weight average molecular weight of the resin (A) (measured by gel permeation chromatography and converted to standard polystyrene) is 20, 20 in view of coatability and heat resistance.
It is preferably from 000 to 300,000.

In order to impart alkali developability to the photosensitive resin composition of the present invention, the acid value (mgKOH / mg KOH /
g) is preferably from 90 to 140. From the viewpoint of heat resistance, the concentration of the ethylenically unsaturated group of the component (A) is as follows:
It is preferable that the concentration be 0.5 to 3.0 mmol / g.

The amount of component (A) is (A) and (B)
It is preferably from 40 to 75 based on 100 parts by weight of the total amount of the components.
Parts by weight. If the amount is less than 40 parts by weight, the coating properties will be insufficient, and if it exceeds 70 parts by weight, the film properties of the cured product will tend to deteriorate.

As the photopolymerizable compound (B) having at least two ethylenically unsaturated groups, for example, a compound obtained by reacting an α, β-unsaturated carboxylic acid with a polyhydric alcohol (polyethylene glycol diacrylate) (Those having 2 to 14 ethylene groups), trimethylolpropane diacrylate, trimethylolpropane triacrylate, tetramethylolmethane triacrylate,
Α, β-unsaturated carboxylic acid to glycidyl group-containing compounds such as tetramethylolmethane tetraacrylate, polypropylene glycol diacrylate (having 2 to 14 propylene groups), dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, etc. (Trimethylolpropane triglycidyl ether triacrylate, bisphenol A diglycidyl ether diacrylate, etc.) and diacrylate of bisphenol A alkylene oxide adduct (2,2'-bis [4- (methacryloxy) Diethoxy) phenyl] propane, 2,2'-bis [4- (methacryloxypentaethoxy) phenyl] propane, etc.), diisocyanate, dialcohol and acrylic acid hydroxymonoester. And a urethane diacrylate compound obtained by reacting These monomers are used alone or in combination of two or more.

The amount of component (B) is as follows: component (A) and component (B)
Preferably from 15 to 60 parts per 100 parts by weight of the total amount of the components
Parts by weight. If the amount is less than 15 parts by weight, the photosensitivity is insufficient and the film properties of the cured product are reduced, and if it exceeds 60 parts by weight, the coating properties tend to be insufficient.

As the photopolymerization initiator (C) used in the present invention, for example, aromatic ketones (benzophenone, 4,
4'-bis (dimethylamino) benzophenone (Michler's ketone), 4,4'-bis (diethylamino) benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, etc., alkylaminobenzoic acid derivatives (dimethylaminobenzoethyl, dimethylamino) Benzoyl ethyl, etc.), anthraquinone derivatives (2-ethylanthraquinone, phenanthraquinone, etc.), thioxanthone derivatives (thioxanthone, 2,4-diethylthioxanthone, etc.), benzoin derivatives (benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether) , Methylbenzoin, ethylbenzoin, etc.), benzyl derivatives (benzyl, benzyldimethylketal, etc.), 2,4,5-triarylimidazole dimer (2- (o-chloro) Eniru) -4,5-diphenyl imidazole dimer, 2-(o-chlorophenyl) -
4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl)
-4,5-diphenylimidazole dimer, 2- (p-
(Methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) -4,5-diphenyl Imidazole dimer,
2- (p-methylmercaptophenyl) -4,5-diphenylimidazole dimer, etc.), acridine derivative (9
-Phenylacridine, 1,7-bis (9,9'-acridinyl) heptane, etc.), morpholino group-containing compounds (2-methyl- [4- (methylthio) phenyl] -2-
Morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 and the like. These are used alone or in combination of two or more.

The amount of component (C) used is (A) and (B)
The amount is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of the components. If the amount is less than 0.1 parts by weight, the light sensitivity tends to be low. If it exceeds 10 parts by weight, heat resistance tends to decrease.

As the black pigment of the component (D), for example,
Carbon black. The pigment particle size is 0.03
It is preferable that the thickness is less than 0.8 μm, and if it is less than 0.03 μm, the black pigment tends to flow out of the spacer after enclosing the liquid crystal. There is a tendency that minute chips are generated at the time of manufacturing the panel, and a problem that the transparency of the panel is reduced occurs. More preferably, the pigment particle size is 0.05 to 0.5 μm. In the present invention, by making the spacer formed by using the component (D) black, it is possible to block the intrusion of undesired photons into the driving circuit of the liquid crystal display device, and to prevent the liquid crystal display device from malfunctioning (panel malfunctioning). ) Can be almost completely suppressed.

The amount of the component (D) is between (A) and (B).
The amount is preferably 10 to 40 parts by weight based on 100 parts by weight of the total amount of the components. If the amount is less than 10 parts by weight, coloring tends to be insufficient. If it exceeds 40 parts by weight, the cured resist tends to become brittle.

Examples of the (E) thermosetting resin in the present invention include epoxy resins, phenol resins, and melamine resins such as hexamethoxymethylmelamine. The amount of the component (E) is preferably 5 to 20 parts by weight based on 100 parts by weight of the total of the components (A) and (B). If the amount is less than 5 parts by weight, heat resistance and adhesiveness tend to be insufficient. If the amount exceeds 20 parts by weight, storage stability and developability tend to decrease.

The photosensitive resin layer may contain a dye, a color former, a plasticizer, a pigment, a flame retardant, a thermal polymerization inhibitor, an adhesion promoter, and the like, if necessary, in a total amount of 100 parts by weight of the components (A) and (B). May be contained in an amount of about 0.1 to 15 parts by weight.

The photosensitive resin composition of the present invention comprises a solvent which dissolves the above components, for example, toluene, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve, ethyl cellosolve, propylene glycol monomethyl ether, chloroform, methylene chloride, methyl Alcohol, ethyl alcohol and the like may be contained. When a solvent is used, the amount used is such that the solid content of the solution is 5-9.
It is preferable to set the amount to be 5% by weight in view of applicability and workability.

The photosensitive resin film for forming a colored resin spacer according to the present invention comprises a support film and a solution obtained by dissolving the above components in a solvent, a roll coater, a comma coater, a gravure coater, a microgravure coater, an air knife coater, a die coater, and a slot coater. After coating and drying with a die coater, a bar coater or the like, a protective film can be laminated and manufactured.

The photosensitive resin layer (b) of the photosensitive film for forming a colored resin spacer has a thickness of 3 to 10 μm. Thickness 3
If it is less than μm, the coating properties will be insufficient, and streaks and uneven thickness will occur. If it exceeds 10 μm, the resolution will decrease.

The photosensitive film for forming the colored resin spacer of the present invention The spacer using the photosensitive film is manufactured as follows. First, a substrate on which a black matrix, color pixels, and the like are formed as necessary on a glass plate or the like is heated (at 70 to 150 ° C. for 3 to 15 minutes) or without heating. Laminating (laminating) the photosensitive resin layer while peeling off the protective film of the film
Then, after the support film on the surface of the photosensitive resin layer is not peeled off or peeled off, the photosensitive resin layer is exposed with a negative mask having a predetermined pattern placed thereon. At this time, the photosensitive resin layer and the negative mask may be in either contact or non-contact state. Next, the unexposed portion is removed by development with a developing solution, and further, after-baked at 150 to 200 ° C. for about 15 to 45 minutes as necessary. Either a method in which the support film is not peeled off in the exposure step or a method in which the support film is peeled may be used. In particular, the latter method is preferably used to improve the line accuracy of the pattern.

The laminating step is performed while heating and softening the photosensitive resin layer with a heatable roll called a hot roll or a heating jacket called a heat shoe and a roll called a laminating roll. The exposure step is performed using a contact or non-contact type. Examples of the lamp include a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, and a xenon lamp. The exposing machine used at this time includes a scattered light exposing machine, a parallel light exposing machine, a proximity exposing machine, a stepper, a laser exposure and the like.
Further, after-baking is performed by a heat source such as a batch-type or continuous-type dryer, and an IR furnace or the like can be used. In these methods, after the lamination, the exposure, and the development, a chemical solution treatment and an electric treatment may be added or performed as necessary.

The developing method includes a dip method, a spray method and the like, and a high-pressure spray method is most suitable for high resolution. As the developer, for example, an aqueous solution of 0.05 to 1.5% by weight of sodium carbonate, an aqueous solution of potassium hydroxide of 0.05 to 1.0%, an aqueous solution of sodium hydroxide, an aqueous solution of trimethylol ammonium hydroxide, or the like is used. it can.
In particular, the use of 0.1 to 0.5% by weight of sodium carbonate improves the resolution and adhesion.

[0032]

Next, the present invention will be described with reference to examples. Examples Table 1 below on a support film (polyester film)
Apply the solution for photosensitive resin layer shown in
It was dried for 5 minutes in a hot air convection dryer at 0 ° C.
μm). Further, a protective film (polyethylene film) was laminated to obtain a photosensitive film for forming a colored resin spacer. While peeling off the protective film, this photosensitive film, red on a glass plate with a black matrix,
On the substrate on which the blue and green pixels were formed and on which a resin overcoat layer was formed over the entire surface, the photosensitive resin layer was turned, and a roll temperature of 110 ° C., a roll pressure of 6 × 10 ⁵ Pa, and a speed were applied by a laminator. Lamination was performed at 5.0 m / min. Next, after removing the polyester film film and exposing at 80 mJ / cm ² with a proximity exposure machine (manufactured by Hitachi Electronics Engineering Co., Ltd.) through a negative mask of a predetermined pattern, a 0.15 wt% sodium carbonate aqueous solution (2
(3 ° C.) for 20 seconds to develop and remove unexposed portions to obtain a substrate on which a black pattern was formed.

The black pattern is uniformly formed with a predetermined shape and excellent mechanical properties (hardness). The liquid crystal display device assembled using the substrate on which the black pattern is formed malfunctions. And excellent display characteristics without color unevenness or uneven contrast. Further, in the liquid crystal display device, the black pattern was immersed in the enclosed liquid crystal, but it was confirmed that no abnormality such as cracking occurred.

[0034]

[Table 1]

In Table 1, (* 1) and (* 2) are shown below. (* 1) 100 parts by weight of a styrene / acrylic acid / ethyl acrylate / methyl methacrylate (weight ratio: 30/21/5/44) copolymer is added with 11 parts by weight of glycidyl methacrylate to form a side-chain photopolymerizable unsaturated group. Methacryloyl group-introduced polymer: weight average molecular weight of 40,000 (* 2) trimethylhexamethylene diisocyanate / cyclohexanedimethanol / 2-hydroxyethyl acrylate (2/1/2 molar ratio)

[0036]

According to the photosensitive film for forming a colored resin spacer according to the present invention, a spacer having a uniform thickness and excellent mechanical strength can be easily formed, there is no display unevenness due to a variation in the film thickness, and panel operation reliability can be improved. It is possible to improve the performance.

Continuation of the front page (51) Int.Cl. ⁶ Identification code FI G03F 7/033 G03F 7/033 (72) Inventor Naohiro Tanikawa 4-3-1, Higashicho, Hitachi City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Yamazaki Factory

Claims (1)

[Claims] (1) a support film (b) a film thickness of 3 to 1
In a photosensitive film in which a photosensitive resin layer having a thickness of 0 μm and a protective film (c) are laminated in this order, (b) the photosensitive resin layer is (A) a polymer compound having an ethylenically unsaturated group, (B) at least Forming a colored resin spacer containing a photopolymerizable compound having two ethylenically unsaturated groups, (C) a photopolymerization initiator, (D) a black pigment, and (E) a thermosetting resin and developable with an alkaline aqueous solution Photosensitive film.