JPH07168200A - Electrode plate for display device and its production - Google Patents

Abstract

PURPOSE:To prevent the scratch or discontinuity of a substrate electrode due to pressurizing by providing a region where an over coat layer is absent on a peripheral part of a color filter. CONSTITUTION:This substrate electrode plate for display device is composed of a substrate 1, the over coat layer 2, a transparent electrode 3, a metallic thin film layer 4 and the color filter 5. The substrate 1 is a transparent plate and for example, a float glass (blue plate) having 1mm thickness is used. The transparent electrode 3 is the one generally called ITO. The metallic thin film 4 is formed by laminating three layer of chromium, aluminum and nickel. The over coat layer 2 is for protecting the color filter 5 formed on the substrate 1 and for making the surface of the color filter 5 flat. And the electrode plate for display is provided with the region where the over coat layer is absent, that is a hard region, on the peripheral part of the color filter 5 formed on the substrate 1. Then, the effect upon the hard region even by pressurizing is small.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color liquid crystal, a display, an electrode plate for a display device used for a display / input device using the liquid crystal, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a liquid crystal display for high density display, it is necessary that the intervals between formed pixels and terminals are around 100 μm. On the other hand, the display itself tends to have a larger screen. Therefore, there are two particularly strong demands for lowering the resistance of the transparent electrode from the viewpoint of driving the liquid crystal and for surface mounting the driving IC from the viewpoint of thinning. To meet these requirements, a part of the transparent electrode is provided with a thin wire pattern of a metal thin film with a width of several tens of μm as an auxiliary conductor for lowering the resistance, or a metal thin film is formed on the terminal part of the liquid crystal panel to surface mount. It is a known technique to deal with the use.

An electrode plate having a transparent electrode formed on a color filter used in such a color liquid crystal display is capable of driving a liquid crystal more easily and more accurately than a transparent electrode formed below the color filter. You can Also, in terms of display quality, it is remarkably excellent in terms of visibility and hue. In such an electrode plate, since the transparent electrode is patterned by etching, providing a protective layer of an organic resin between the color filter and the transparent electrode for the purpose of imparting acid resistance to the color filter,
It is generally done.

[0004]

However, when a heat treatment is carried out after forming a protective layer of an organic resin on a color filter formed by printing or dyeing, wrinkles and blisters occur in the protective layer. In particular, in the case of a color filter by dyeing, in addition to this defect, there is a defect that discoloration or fading easily occurs by heat treatment after forming the transparent electrode. This is particularly remarkable when a material that easily hydrolyzes, such as an acrylic resin or gelatin, is used for the protective layer.

Further, although polyimide and silicon resins have heat resistance, they are too expensive to be used as a protective layer material.

When a resin is coated on the entire surface of the electrode plate to provide a protective layer, the transparent electrode is formed on the protective layer. Here, since the protective layer is soft as compared with the substrate and the transparent electrode, when a force is applied from above the transparent electrode, the transparent electrode will be separated due to the difference in hardness between the protective layer and the transparent electrode on the transparent substrate. It is easily scratched and disconnection occurs at the electrical connection from the end of the electrode plate.

[0007]

Therefore, in the electrode plate for a display device according to claim 1 of the present invention, a color filter, an overcoat layer and a transparent electrode are sequentially formed on a transparent substrate. The electrode plate for display thus obtained is characterized in that it has a region having no overcoat layer in the peripheral portion of the color filter.

Further, the electrode plate for a display device according to a second aspect is characterized in that the transparent electrode is directly formed in a region without the overcoat layer.

Further, in the electrode plate for a display device according to the third aspect, the overcoat layer is made of a resin having an alkali developable and photocurable phenol novolac epoxy resin as a skeleton. It has a feature.

In the method of manufacturing an electrode plate for a display device according to a fourth aspect, a transparent substrate is provided with a color filter, and then an alkali-developable and photocurable phenol novolac epoxy resin is used. A photosensitive resin having a skeleton as a uniform coating, and the selective exposure of the epoxy resin,
By developing and drying, an overcoat layer is provided on the color filter, a region without the overcoat layer is provided in the peripheral portion of the color filter, and then a transparent electrode is formed.

Further, the manufacturing method of the electrode plate for a display device according to the fifth aspect is characterized in that the transparent electrode is directly formed in the region without the overcoat layer.

[0012]

In the electrode plate for a display device according to the first aspect of the present invention, the overcoat layer protects the color filter formed on the substrate and flattens the surface of the color filter. Further, the region without the overcoat layer provided on the transparent substrate is harder than the region with the overcoat layer.

Further, in the electrode plate for a display device according to the second aspect, the transparent electrode directly formed in the region without the overcoat layer is less likely to be scratched or broken.

Further, in the electrode plate for a display device according to claim 3, the overcoat layer made of a photocurable phenol novolac epoxy resin, which is alkali-developable, has a hardness that can withstand a liquid crystal process after the development treatment. have.

In the method for manufacturing an electrode plate for a display device according to a fourth aspect, the alkali-developable and photocurable phenol novolac epoxy resin can be easily patterned by exposure, development and drying. You can Therefore, it is easy to form a region without an overcoat layer. In addition, the epoxy resin can form an overcoat layer having excellent heat resistance, alkali resistance, and solvent resistance.

Further, in the method for manufacturing the electrode plate for a display device according to the fifth aspect, since the transparent electrode is directly formed in the region without the overcoat layer, the transparent electrode can be formed without being damaged by pressure.

[0017]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an electrode plate for a display device of this embodiment. In the figure, 1 is a substrate, 2 is an overcoat layer, 3
Is a transparent electrode, 4 is a metal thin film layer, and 5 is a color filter.

The substrate 1 is a transparent plate, and in this embodiment, a float glass (blue plate) having a thickness of 1 mm is used. The overcoat layer 2 is for protecting the color filter layer. The transparent electrode 3 is generally called ITO. And the metal thin film 4
Is formed by stacking three layers of chromium, aluminum and nickel.

The electrode plate for a display device having the above structure is manufactured as follows.

A color filter 5 of three colors of green (G), red (R) and blue (B) was sequentially formed on the substrate 1 by a relief dyeing method, which is a known technique, with a thickness of about 1.8 μm. Subsequently, a polymer of a reaction product of a phenol novolac epoxy resin and a dicarboxylic acid anhydride (having a photosensitivity by adding an acrylyl group) was coated so that the film thickness after drying was about 1 μm.

The thus-obtained material was exposed to ultraviolet rays, the unexposed portion was developed and removed with a 1% aqueous solution of sodium carbonate, and a color filter was patterned in a rectangular shape so as to cover almost the entire surface. And

Next, using the technique of ion plating, 80
A conductive plate 3 called ITO of 0Å was laminated. Furthermore,
Chromium 800Å and aluminum 1400 by vapor deposition
Å and nickel were sequentially laminated in a thickness of 800 Å to form a metal thin film 4.

By a known wet etching, nickel, aluminum, chromium, and ITO were sequentially patterned to manufacture an electrode plate for a display device for a color liquid crystal.

The present invention is not limited to the above embodiment. For example, in the above embodiment, IT
Although the thicknesses of O, chromium, aluminum, and nickel are shown, the thicknesses are not limited to these. In addition, the metal thin film,
It may be an alloy layer or another good conductor. Alternatively, only the transparent electrode may be formed without forming the metal thin film. Further, an oxide may be formed on the base of the transparent electrode.

The structure may be either an inorganic oxide layer inserted between the overcoat layer and the transparent electrode or a metal thin film formed so as to partially overlap the transparent electrode. Even if there is a difference, the obtained effect and the action can be identified. Of these, the film thickness of the overcoat layer is preferably 200 Å or more because the protective effect of the color filter becomes low when the film thickness is 200 Å or less, and is preferably 50,000 Å or less because absorption of short wavelength light gradually occurs when the film thickness is 50000 Å or more.

However, if a little coloring does not matter, a film thickness of 50,000 Å or more may be used. Further, for the purpose of improving the adhesiveness between the color filter and the overcoat layer, a surface treatment may be performed with a coupling agent. In addition, in order to promote the flattening of the color filter, a layer of peptide resin such as gelatin or casein, a layer of polyvinyl alcohol, etc. may be inserted under the overcoat.

The color filter is not limited to a method and material such as those formed by a photolithography method and those formed by printing.

[0029]

In the electrode plate for a display device according to the first aspect of the present invention, the color filter formed on the substrate has a peripheral region having no overcoat layer, that is, a hard region. Therefore, even if pressure is applied, the influence on the hard region is small.

Further, in the electrode plate for a display device according to the second aspect of the present invention, since the transparent electrode is less scratched by the pressure, disconnection does not occur at the electrical connection portion from the end of the electrode plate. Further, since the electrode can be taken out very stably in the electrical connection between the transparent electrode and the external lead, the transparent electrode can be easily mounted.

In the electrode plate for a display device according to the third aspect, since the photosensitive resin is used, the overcoat layer can be formed only on the color filter and the peripheral edge portion of the electrode plate can be removed by the developing treatment. Further, since the phenol novolac-based epoxy resin has a three-dimensional stitch structure, it has heat resistance and does not cause wrinkles or discoloration of the color filter during heat treatment after the transparent electrode is formed.

In the method for manufacturing the electrode plate for a display device according to the fourth aspect, since the photocurable phenol novolac epoxy resin is used, the overcoat layer is formed only on the transparent substrate at a necessary portion. Is easy to provide.

In the method of manufacturing the electrode plate for a display device according to the fifth aspect, the transparent electrode can be formed in the region without the overcoat layer without damaging it.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electrode plate for a display device of the present invention.

[Explanation of symbols]

 1 ... Substrate 2 ... Overcoat layer 3 ... Transparent electrode 4 ... Metal thin film 5 ... Color filter

Claims (5)

[Claims] 1. A display electrode plate in which a color filter, an overcoat layer, and a transparent electrode are sequentially formed on a transparent substrate, wherein the color filter has no overcoat layer in the periphery thereof. An electrode plate for a display device having a region. 2. The electrode plate for a display device according to claim 1, wherein the transparent electrode is directly formed in a region having no overcoat layer. 3. The overcoat layer is made of a resin having an alkali developable and photocurable phenol novolac epoxy resin as a skeleton. Electrode plate for display device. 4. A transparent substrate is provided with a color filter, and then a photosensitive resin having an alkali-developable and photocurable phenol novolac epoxy resin as a skeleton is uniformly applied. By selectively exposing, developing and drying, an overcoat layer is provided on the color filter, a region without the overcoat layer is provided in the peripheral portion of the color filter, and then a transparent electrode is formed. Of manufacturing an electrode plate for a display device. 5. The method for manufacturing an electrode plate for a display device according to claim 4, wherein the transparent electrode is directly formed in a region without the overcoat layer.