JPH05232312A - Production of light shielding layer of color filter for liquid crystal display element - Google Patents

Abstract

PURPOSE:To easily and efficiently obtain a patterned light shielding layer at high accuracy by applying a specified ink compsn., curing, and then removing a photosensitive resin layer and a silicone rubber layer by the same means as used for a developing process. CONSTITUTION:A photosensitive resin layer which becomes soluble in an area exposed to light and a silicone rubber layer are laminated in this order on the surface of a light-transmitting base body. This laminated body is exposed and developed by photolithography to remove the exposed area of the silicone rubber layer and the photosensitive resin layer under the silicone rubber layer to form a pattern. Then an ink compsn. containing a black coloring material which is cured with light or heat is applied on the pattern part and subjected to posttreatment. Then the photosensitive resin layer 5 remaining on the substrate where the layer is not exposed in the pattern exposing process is exposed over the whole surface to become soluble. Then the remaining photosensitive layer is removed with the upper silicon rubber layer. In this case, the silicone rubber layer has to have repelling effect against the ink compsn. used for coloring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a color for a liquid crystal display device.
The present invention relates to a method for producing a light-shielding layer provided between pixels of a filter simply and with high accuracy, and providing colored pixels of three primary colors of RGB by a conventional technique to provide a color filter for a liquid crystal display device. Is.

[0002]

2. Description of the Related Art A color filter for a liquid crystal display device is an essential member for colorizing a liquid crystal display device and is formed by forming colored pixels on a glass or transparent plastic substrate. Red (R), green (G), and blue (B) pixels of the three primary colors are arranged in a line or mosaic, and the size is 10
It is around 0 μm. A light-shielding layer generally called a black matrix is formed between each pixel in order to enhance the contrast of an image. In the active matrix driving method, a light shielding portion is formed to shield the transistor and the wiring portion.

The black matrix is usually formed by etching a metal chromium deposition film or a sputtering film, and is formed in a stripe shape, a mosaic shape, a grid shape, or the like corresponding to the arrangement of each pixel of RGB. However, the width is several μm in a narrow place and about 100 μm in a wide place. It is essential to produce a chromium thin film uniformly and without defects such as pinholes,
Patterning requires processing steps such as resist coating, exposure / development, baking, etching, and resist stripping.

There have been attempts to produce these light-shielding layer patterns using a photosensitive resist material containing a black coloring material, but it is difficult to achieve both high light-shielding effect and high sensitivity and high resolution. Although a method of pattern-coating an ink containing a photosensitive or non-photosensitive black coloring material by a printing method has been proposed, it is very difficult to form a pattern of 10-50 μm size.

Since a high light-shielding property and a high-precision pattern forming property are required, a metal chromium thin film is currently produced by etching. A dyeing method, a pigment dispersion method, an electrodeposition method, a printing method, and the like have been proposed as methods for forming pixel portions of three primary colors of RGB on a substrate on which a black matrix is formed.

[0006]

The present invention was devised in view of the above-mentioned drawbacks of the prior art. The purpose of the present invention is a pattern which is essential for improving the quality of color filters.
An object of the present invention is to provide a method for producing a light-shielding light-shielding layer, which is simpler, more efficient, and highly accurate.

[0007]

According to the present invention, a photosensitive resin layer and a silicone rubber layer in which exposed portions are solubilized are laminated in this order on the surface of a light-transmissive substrate, and then the laminated body is subjected to a photolithography method. By exposing and developing, the silicone rubber layer in the exposed portion and the photosensitive resin layer thereunder are both removed to form a pattern, and then a black coloring material is included and cured by the action of light, heat, etc. After the ink composition is applied to the pattern portion and post-treated, the residual photosensitive resin layer, which was the non-exposed portion at the time of the pattern exposure, is exposed to the entire surface to be solubilized and the silicone on the upper portion. The present invention relates to a method of manufacturing a light shielding layer of a color filter for a liquid crystal display element, which is characterized in that it is removed together with a rubber layer.

That is, according to the present invention, after the ink composition containing a black coloring material which is mainly thermosetting is applied to the concave portion formed by the repulsive silicone rubber layer patterned by photolithography and then cured, The light-shielding layer pattern is formed by removing the photosensitive resin layer used for the patterning and the silicone rubber layer thereover by the same means as in the developing step.

Since it is not necessary to photo-cure the composition colored in black, it is possible to increase the concentration of the coloring component for light shielding. There are no problems such as complicated processes such as the method using a metal chrome thin film and obstacles due to high reflectance and toxicity of materials. In addition, it is possible to achieve several steps of high accuracy compared to the printing method.

The light-transparent substrate used in the present invention is a glass or transparent plastic sheet, on which a photosensitive resin layer and a silicone rubber layer are formed in this order with or without an underlayer.

The photosensitive resin layer used in the present invention is of a type in which the exposed area changes and is solubilized. As a photosensitive resin composition having a property that the exposed portion changes and becomes soluble,
There is a positive type resist used for manufacturing. As the positive resist, for example, a cresol-novolak resin is mixed with a naphthoquinonediazide compound, and a commercially available resist can be used as it is.

A silicone rubber layer having a resilience performance is formed on the photosensitive resin layer. The solubility of the photosensitive resin layer changes due to changes in the physical properties due to exposure, and this is used to develop and pattern. At this time, by devising the photosensitive resin layer, it is possible to remove both the photosensitive resin layer in the exposed portion and the silicone rubber layer thereabove, or to remove only the silicone rubber layer. Generally, both layers are removed.

It is essential that the silicone rubber layer coated on the surface layer has a repulsive effect with respect to the ink composition used for coloring, but it is not limited thereto, but the following repeating units are included. The main component is a linear organic polysiloxane having a molecular weight of several thousand to several hundred thousand.

[0014]

[Chemical 1] (Here, n is an integer of 2 or more, and R is an alkyl group, an alkenyl group, or a phenyl group having 1 to 10 carbon atoms.) By sparsely crosslinking such a linear organic polysiloxane, a silicone rubber can be obtained. .. The cross-linking agent is acetoxysilane, ketoxime silane, alkoxysilane, aminosilane, amidosilane, alkenioxysilane, etc. used for so-called room temperature (low temperature) curing silicone rubber, and usually has a terminal as a linear organic polysiloxane. Combined with those having a hydroxyl group, they become deacetic acid type, deoxime type, dealcohol type, deamine type, deamidation type and deketone type silicone rubbers, respectively. Further, a small amount of an organic tin compound or the like is added as a catalyst to the silicone rubber. In order to bond the photosensitive resin layer and the silicone rubber layer, various adhesive layers may be used between the layers, and aminosilane compounds and organic titanate compounds are particularly preferable. Instead of providing an adhesive layer between the photosensitive resin layer and the silicone rubber layer, an adhesive component may be added to the silicone rubber layer. An aminosilane compound or an organic titanate compound can also be used as the added adhesive component.

The photosensitive resin layer is formed by a dipping method, a roller coat method.
It is formed by using a coating device such as a coater, a spin coater such as a holer, a spinner and the like. If necessary, apply and dry the adhesive layer in the same manner as above, then apply the silicone rubber layer in the same manner and heat-treat at a temperature of 100-130 ° C for several minutes to form the silicone rubber layer. To do. If necessary, a protective cover
The film may be covered on the silicone rubber layer with a laminator or the like. Protective film is stored, transported,
This is to prevent damage to the surface silicone rubber layer during handling or during the working process. Generally, polypropylene or polyester film is used.

The pattern formation is performed by a usual photolithography technique. After exposure with light from a mercury lamp or a metal halide lamp through a pattern mask, the photosensitive resin and silicone rubber in the exposed area are removed using a mixed solvent of hydrocarbon and alcohol for development, for example.
A concave pattern surrounded by the surface layer of silicone rubber corresponding to the black matrix is formed.

An ink composition containing a black coloring material is applied to the depressions by means of a roller coater or the like. The area other than the patterned recesses is a repulsive silicone rubber layer, and the ink composition is repelled and is efficiently applied only to the recesses. Although the thickness of the ink composition layer is determined by the light-shielding efficiency, it also depends on the depth of the recesses, so that it can be dealt with by controlling the coating thickness of the photosensitive resin layer and the silicone rubber layer. It is also necessary to consider shrinkage due to drying or curing treatment.

The ink composition containing the black coloring material is required to have a visible light shielding effect. Since resistance to heat resistance, chemical resistance, etc. in the RGB processing step is required, it is usually suitable to use a cured resin having a three-dimensional structure. For the curing, a method mainly using heat is recommended. Since it is necessary to add a large amount of pigment such as carbon black for coloring, heat is more effective than curing by light. It is effective from a process point of view to cure only the surface layer by light and to provide only the resistance when the unnecessary silicone rubber layer is removed together with the underlying photosensitive resin layer. After the ink composition is applied to the pattern recesses and exposed to light, the photosensitive resin layer in the remaining portion reacts to change the physical properties and the pattern is appropriately developed as in the case of developing the pattern earlier. It becomes soluble in the solvent and can be removed. The order in which the step of removing the unnecessary portion and the curing of the coloring material are performed can be determined in consideration of the properties of the ink composition used.

The coloring material is a composition mainly composed of a dye or pigment serving as a coloring component for blocking visible light and a resin component for forming a film or a resin forming component.

As means for curing the film-forming component, there are room temperature drying, forced drying, heat drying, high energy ray irradiation, etc., all of which are industrially carried out. Heat curing and ultraviolet ray / electron beam irradiation curing are preferable in terms of rapid processing. Various resin components are used as a film-forming component (binder) of a composition that forms such a film. The heat-drying composition includes amino alkyd resin, epoxy resin, urethane resin, polyester resin,
There is a phenol resin, and examples of the UV-curable binder include unsaturated polyester resin, acrylic oligomer, modified silicone resin, acrylic resin, epoxy resin, cinnamic acid resin and polythiol resin. ..

In the curing of the melamine-alkyd resin, the reaction between the melamine resin and the alkyd resin and the self-condensation of the melamine resin simultaneously proceed to become three-dimensional and to cure. P-Toluenesulfonic acid and its derivatives are effective for curing. Although not limited to this, a melamine resin in which carbon black is dispersed, or a melamine resin further mixed with an alkyd resin can be used.

It is possible to cure with light, but it is necessary to add a large amount of pigment components such as carbon black,
Since it is not advisable to cure the entire coating by irradiating it with ultraviolet rays, it is preferable to use ultraviolet rays for initial curing or to cure only the surface layer and to use heat for the overall curing. For example, it is a method in which an ultraviolet curable ink is used and a thermosetting component or a radical generator is added to the ink. UV cure inks are available from many ink manufacturers, so they can be used. Furthermore, the UV curing ink developed for waterless planographic printing is more preferable. For example, it is a “best cure” type manufactured by Toka Color Chemical Co., Ltd. To impart thermosetting properties, a thermal radical polymerization initiator such as a peroxide or an azobis compound is added.

As an example, a black color of "Color Mosaic" sold by Fuji Hunt Co., Ltd. as a photosensitive paste for a color filter to which a thermal polymerization initiator is added is used. In addition, a composition used as a thermosetting paint or ink can be used as a base, and a composition having improved heat resistance and chemical resistance can be used.

[0024]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 A naphthoquinone-1,2-diazide-5 of a phenol novolac resin (Sumitomo Becklite, "Sumiresin PR50235") having an esterification degree of 45% was placed on a glass substrate having a SiO ₂ film formed on the surface thereof. -10 wt.% Of sulfonic acid ester (molecular weight about 1300)
Apply dioxane solution and dry in hot air at 60 ℃, thickness 2
A μm photosensitive resin layer was provided. A 0.5 wt% n-heptane solution of γ-aminopyropyrtriethoxysilane (manufactured by UCC: A1100) was applied onto this and dried at 100 ° C. On top of this,
A 10 wt% n-heptane solution of a silicone rubber composition having the following composition was applied and dried at 100 ° C to obtain a 1 μm silicone composition.
The rubber layer was installed.

Silicone rubber layer composition a. Polydimethylsiloxane (Molecular weight: about 80,000, -OH groups at both ends) 100 wt. Parts b. Methyltriacetoxysilane 5 wt part c. Dibutyltin acetate 0.2 wt parts Exposed to the coated substrate prepared as above through a mask of the pattern of the light-shielding layer with an ultra-high pressure mercury lamp exposure machine, and n-heptane /
The surface was lightly rubbed with a pad containing an ethanol (1: 1) mixture to remove the exposed photosensitive layer and the silicone rubber layer on it, and then washed thoroughly to form a pattern. The manufactured substrate was produced.

Sumitomo Chemical Co., Ltd. "Sumiresin" M3 (methylolated melamine) 5 wt% of hydroxypropyl cellulose and a curing agent ACX (Sumitomo Chemical Co., Ltd.) was added to an aqueous solution A black coloring material prepared by mixing Black # 7360 of HI Micron K Color Co., Ltd. in a ratio of 1: 1 was placed on the substrate and applied to the concave portion patterned by a rubber roller. The ink composition is applied only to the recesses because the portions other than the recesses are the silicone rubber layer and the coloring material is repelled and brought to the rubber roller side.

When the melamine resin is cured by heating at 100 to 120 ° C., it develops resistance to the solvent used for development. Therefore, after this heat treatment, the entire surface is exposed to n-heptane / ethanol.
It was immersed in a (1: 1) mixed solution and lightly rubbed from the surface for development to remove the unnecessary silicone rubber layer and the photosensitive resin layer thereunder. Only the patterning of the black coloring material remains on the substrate. This was further heat-treated to improve heat resistance and chemical resistance.

A color filter was manufactured by applying a photosensitive paste method to the formation of RGB pixels.

Example 2 A pattern in which the silicone rubber layer was removed in the same manner as in Example 1.
U for waterless lithographic plate made by Toka Color Chemical Co., Ltd.
The black ink of V-ink "Best Cure" 171A was applied on the surface using a rubber roller and filled in the patterned recesses. The entire surface is irradiated with the UV light of an ultra-high pressure mercury lamp to cure the filled UV ink, and at the time of the pattern of the silicone rubber layer, the unexposed portion is photoreacted and soluble in the developing solution. To the state of. n-heptane / ethanol (1: 1)
The surface is lightly rubbed with a pad containing the mixed solution to dissolve and remove the silicone rubber layer and the photosensitive resin layer thereunder. This leaves a pattern of black ink on the substrate. Post curing was performed at 200 ° C for 30 min. To further cure the ink. The glass substrate having the light-shielding layer pattern thus produced can be used for forming colored pixels by a pigment dispersion method, a printing method, or the like.

Claims (4)

[Claims] 1. A photosensitive resin layer and a silicone rubber layer in which an exposed portion is solubilized are laminated in this order on the surface of a light-transmitting substrate, and the laminated body is exposed by a photolithography method.
By developing, the silicone rubber layer in the exposed portion and the photosensitive resin layer thereunder are both removed to form a pattern,
Then, after applying an ink composition containing a black coloring material and curable by the action of light, heat, etc. to the pattern portion and performing a post-treatment, the residual photosensitive resin which was the non-exposed portion at the time of the pattern exposure. A method for producing a light-shielding layer for a color filter for a liquid crystal display device, which comprises solubilizing the entire surface by exposure to light and removing the layer together with the upper silicone rubber layer. 2. A light-transmitting substrate surface is provided with a photosensitive resin layer to be laminated thereon or a base layer having an affinity or an adhesive effect to the ink composition to be coated. Item 2. A method for producing a light-shielding layer of a color filter for a liquid crystal display element according to item 1. 3. A light-shielding layer of a color filter for a liquid crystal display device according to claim 1, wherein the light-shielding layer is formed of an ink composition containing a black coloring material and cured by the action of heat. Law. 4. The color for a liquid crystal display device according to claim 1, wherein the light-shielding layer is formed of an ink composition containing a black coloring material, which is initially cured by the action of light and then thermally cured. A method of forming a light shielding layer of a filter.