JPH01239522A - Electrode plate for display device and its production - Google Patents

Abstract

PURPOSE:To facilitate admission of a color filter for an electrode plate for a display device into a production line by forming a colored layer constituted of a coloring material dispersed on a transparent substrate with a photosensitive resin consisting of a skeletonal phenol novolak type epoxy resin as binder, then forming a color pattern by exposing and developing the colored layer, and repeating the prepn. stage plural times. CONSTITUTION:A green layer 26 is formed by coating a whole surface of a transparent substrate 21 with a resinous liquid prepd. by dispersing a green pigment obtd. by kneading it with a phenol novolak type epoxy resin and an org. solvent. The green layer 26 is exposed to ultraviolet rays through a mask pattern to harden necessary parts only, and a green pattern 36 is obtd. by removing unnecessary parts by developing with aq. sodium carbonate. Thereafter, a color filter 66 is prepd. by forming a red pattern 57, and a blue pattern by a similar procedure. Since the resin is inexpensive unlike polyimide resin, and the patterns are obtd. by developing with aq. alkali, the process can be admitted into a production line relatively easily.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to color liquid crystal displays and displays using liquid crystals.
The present invention relates to a method of manufacturing an electrode plate for a display device used in an input device or the like.

<Prior art> In a color liquid crystal display, an electrode plate in which a transparent electrode is formed on a color filter is significantly superior to one in which a transparent electrode is formed under a color filter in terms of liquid crystal driving and display quality. ing. Since the transparent electrode is punctured by etching, it is common practice to provide a protective layer of organic resin between the color filter and the transparent electrode in order to impart acid resistance to the color filter.

Photolithography methods, printing methods, and other methods are used to form color filters, and polypeptide resins such as gelatin and casein, acrylic resins, epoxy resins, and polyimide resins are used as base materials for color filters. .

Liquid crystal displays are required to have pixels and terminal pitches of around 100 μm for high-density display. At the same time, screens are becoming larger.

Therefore, there are two particularly strong demands for lower resistance of transparent electrodes from the viewpoint of driving liquid crystals, and surface mounting of drive ICs from the viewpoint of thinning. It is a well-known technique to provide a thin line pattern of a metal conductive film with a width of several tens of micrometers as an auxiliary conductor to lower the resistance on the LCD panel, or to form a thin metal film on the terminals of a liquid crystal panel to support surface mounting applications. be.

<Problem to be solved by the invention> An electrode plate in which a transparent electrode is formed on a protective layer of organic resin formed on a color filter formed by printing or dyeing, or directly on a color filter, is not suitable for post-processing. It has the disadvantage of causing wrinkles and blisters during heat treatment. This tendency is particularly strong in color filters based on acrylic. Furthermore, color filters made from dyed gelatin, grue, casein, etc., have the disadvantage of being susceptible to discoloration or fading during alignment film treatment or heat treatment during the liquid crystal cell formation process.

Although polyimide and silicone resins are heat resistant, they are extremely expensive and cannot be used as color filter materials or protective layer materials. Furthermore, if the entire surface of the color filter electrode plate is coated with these heat-resistant resins, a problem arises in electrical connection from the ends of the electrode plate. This is because there is a resin layer between the transparent electrode and the substrate, so pressure from above tends to damage the transparent electrode. Using a photosensitive polyimide material to form a patterned polyimide protective layer (removing unnecessary portions of the electrode plate edges) would solve the above problem, but photosensitive polyimide is more expensive and Since it is developed using a solvent, it is difficult to incorporate it into a production line. Therefore, there has been a need for a colored layer structure of a color filter that is inexpensive, easy to incorporate into a production line, and does not change in quality due to heat treatment.

Means for Solving the Problems> The present invention provides a method for manufacturing an electrode plate for a display device having at least a color filter and a transparent electrode, in which a photosensitive resin having a skeleton of a phenol novolak epoxy resin is placed on a transparent substrate plate as a binder. A method for manufacturing an electrode plate for a display device, characterized in that the process of forming a colored layer in which a coloring material is dispersed as a film and then exposing and developing it to form a color pattern is repeated multiple times to obtain a color filter. And, in an electrode plate for a display device in which at least a color filter, an overcoat layer, and a transparent electrode are laminated in this order, the color filter is formed from a multicolor color pattern made of a phenol novolak type epoxy resin in which a colorant is dispersed. This is an electrode plate for the device.

In the present invention, in order to reduce the resistance of the transparent electrode and for surface mounting purposes, a metal thin film may be formed so as to partially overlap the transparent snow shovel. In addition, if necessary, SiO□, MgO,
A transparent inorganic oxide layer such as Altos may also be inserted.

In the present invention, as the coloring material of the color filter, in addition to organic pigments and inorganic pigments, it is possible to employ dyes dissolved or dispersed in the base material of the phenol novolac type epoxy resin.

The present invention will be explained in detail based on examples.

<Example> FIG. 1 is a schematic cross-sectional view of an electrode plate for a liquid crystal display device according to the present invention. Figures 2 to 6 show the process of manufacturing an electrode plate for a liquid crystal display device according to the present invention, in which a resin solution made by mixing a phenol novolac epoxy resin with an organic solvent and a film thickness of approximately 1.5 μm after drying is shown. A green layer (26) was formed by coating the entire surface and exposing it to ultraviolet rays through a mask pattern to harden only the necessary areas, and then remove the unnecessary areas by developing with a 1% aqueous solution of sodium carbonate, as shown in Figure 3. It was made into a green pattern (36). Thereafter, a resin liquid in which a red pigment was dispersed was applied to the entire surface to a thickness of about 1.5 μm after drying to form a red layer (47). After exposure to ultraviolet light through the mask pattern again, development was performed to form a red pattern (57) as shown in FIG. Green pattern (36) A blue pattern was also formed in the same process as the red pattern (57) to obtain a color filter (66) shown in FIG.

On the color filter (66), a clear phenol novolak epoxy resin liquid containing no pigment is applied to the entire surface to a thickness of approximately 1.0 μm after drying, and then exposed and developed to form a film on the edge of the electrode plate. An overcoat layer (62) was obtained by removing unnecessary parts of the layer.

Next, a transparent electrode (4) called 800 ITO was formed by sputtering, and a thin metal film (5) was deposited using 800 layers of chromium, 1,400 layers of aluminum, and 800 layers of nickel by vapor deposition. Patterning was carried out in the order of nickel → aluminum → chromium → ITO using a known wet etching method to obtain an electrode plate for a color liquid crystal display device.

In the above embodiments, the overcoat layer on the color filter may be omitted, or an inorganic oxide layer such as SiJ may be formed on the color filter or overcoat a as a protective layer for the color filter or overcoat layer. Also good. In the case of electrode plates for small-sized liquid crystal displays, the formation of the metal thin film shown in the embodiments may be omitted. In addition to the materials shown in the examples, the metal thin film is made of copper, silver,
Good conductors such as gold, tin, and solder alloys are preferable, and thin films of alloys containing additives to prevent migration and improve oxidation resistance may also be used. It is also possible to form these on the ends by plating.

In addition, although three color filters of green, red, and blue are used in the embodiment, a black matrix pattern may be provided to improve display quality. Furthermore, in order to accommodate purposes other than display such as coordinate position input, a sense line made of a metal thin film or a thin film semiconductor pattern such as TPT may be formed on the glass plate before forming the color filter.

<Effects of the Invention> Since the present invention is a color filter using a heat-resistant phenol novolac epoxy resin, it is extremely resistant to heat treatment during the liquid crystal process. Unlike dyed filters such as gelatin and gris, 200
No discoloration or fading occurs even after heat treatment at temperatures between 250°C and 250°C. Similarly, light resistance was also significantly improved.

In addition, unnecessary resin layers at the ends of the electrode plate can be removed by development, so there is no problem with electrical connections at the ends.
The resin used in the present invention is not as expensive as polyimide, and can be developed using alkaline water, making it relatively easy to incorporate it into a production line.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of an electrode plate for a liquid crystal display device according to the present invention. 2 to 6 are schematic cross-sectional views of intermediate products showing the process of the method for manufacturing a liquid crystal display electrode plate according to the present invention. 1.21, 31.41, 51.61...Transparent substrate 36.46.56...Green pattern 57...Red pattern 6.
66...Color filter 2.
62 ...Overcoat layer 4
・・・・・・For transparent electrodes Application by Toppan Printing Co., Ltd. Representative Kazuo Suzuki Figure 1 Figure 2 Figure 4 Figure 5

Claims (1)

[Claims] 1) A method for manufacturing an electrode plate for a display device having at least a color filter and a transparent electrode, which comprises dispersing a coloring material on a transparent substrate using a photosensitive resin having a skeleton of a phenol novolak epoxy resin as a binder. 1. A method for producing an electrode plate for a display device, which comprises forming a colored layer, exposing and developing it to form a color pattern, and repeating the process multiple times to obtain a color filter. 2) At least in an electrode plate for a display device in which a color filter, an overcoat layer, and a transparent electrode are laminated in this order, the color filter has a multi-color pattern made of a phenol novolac epoxy resin in which a colorant is dispersed. An electrode plate for a display device, characterized in that: 3) The electrode plate for a display device according to claim 2, characterized in that a metal thin film is formed so as to partially overlap the transparent electrode.