JPS63197903A - Substrate with transparent conductive color filter - Google Patents

Abstract

PURPOSE:To prevent flawing of a protective layer consisting of a synthetic resin even if a transparent conductive layer is etched to fine patterns by forming a 2nd protective layer consisting of an inorg. material between said protective layer and the transparent conductive layer. CONSTITUTION:The 2nd protective layer 4' consisting of the inorg. material is formed between the protective layer 4 consisting of the synthetic resin and the transparent conductive layer 2. SiO2, Al2O3, TiO2, ZrO2 or Si3N4 with which adhesiveness to the transparent conductive layer 2 to be formed thereon is easily assurable and above all, SiO2 or Al2O3 is preferably used as the 2nd inorg. protective layer 4'. For example, the SiO2 or Al2O3 layer, etc., are formed by a high-frequency sputtering method or vacuum deposition method. The etching of the transparent conductive layer to the fine patterns is thereby permitted without generating overetching and underetching; in addition, the flawing of the protective layer consisting of the synthetic resin is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a substrate with a transparent conductive color filter suitable for use in a liquid crystal display element capable of color display.

[Conventional technology]

Most liquid crystal display elements are monochrome displays, and some that utilize the birefringence effect of liquid crystals or guest-host type (GH type) devices have been put into practical use for color display. With the pursuit of higher performance color display of liquid crystal display devices, it is now possible to express intermediate tones from multi-color display.
7. Demand for so-called color display is increasing.

Full-color display in a liquid crystal display element is realized by a method that combines transparent color filters of the three primary colors of RGB and a black shutter function of the liquid crystal.

There are two types of such full-color displays: the so-called TFT method, in which a film transistor as a driving device for liquid crystal elements and elements is formed directly on a transparent substrate, and the simple matrix type method, which is mainly a TN type liquid crystal. . Furthermore, the simple matrix type method has a lower electrode type in which a color filter layer is formed on a transparent conductive layer formed on a substrate, and a transparent conductive layer formed on a color filter layer formed on a substrate. There are two types of display systems: an upper electrode type that forms a layer.

[Problem that the invention seeks to solve]

As shown in FIG. 3, a liquid crystal display element using a lower electrode type display system has a striped transparent electrode (32) extending perpendicularly to the plane of the paper on a glass substrate (31), and a glass substrate (35) on the other glass substrate (35).
) between the striped transparent ma<3e> on K RGB
It consists of a color filter layer (33) which is a color pixel, a protective layer (34) made of synthetic resin, and a liquid crystal (37) filled with sealing material (3B) K, and two transparent electrodes (
There is liquid between 31) and (32)! In addition to (37), there is a protective layer (34) and a color filter layer (33), so the voltage applied to the transparent electrode t4i (31) (32) cannot be effectively used for the liquid crystal (37) itself. In addition, the thickness of the liquid crystal display element itself has become thicker, and the transmitted light from the oblique direction is transmitted to a part of the black shutter of the liquid crystal and the color filter N1 (3).
Since parallax occurs between each pixel portion (3), there is a drawback that it is difficult to display a clear outline with good contrast. On the other hand, although the liquid crystal display element using the upper electrode type display method is improved in terms of the effective use of the applied voltage and the above-mentioned foot last, since the transparent electrode is provided on the first layer made of synthetic resin, the transparent electrode pattern is The etching process may be difficult or the protective layer may be scratched, causing substances to enter the liquid crystal from the protective layer or color filter layer, reducing the display function of the liquid crystal display element and shortening its lifespan. There were some drawbacks.

[Means for Solving the Problems]” The present invention relates to a substrate with a transparent conductive color filter for eliminating the drawbacks of a liquid crystal display element using an upper electrode type display system.

That is, the present invention provides a transparent substrate, a color filter layer formed on the surface of the transparent substrate, a synthetic resin protective layer formed to cover the color filter layer, and a transparent groove provided on the protective layer. i! A substrate with a transparent conductive color filter comprising a transparent conductive color filter layer, characterized in that an inorganic second protective layer is formed between the synthetic resin protective layer and the transparent conductive layer. The inorganic second protective layer provided between the protective layer and the transparent conductive layer ensures adhesion with the transparent conductive layer formed thereon.5i02
, Al2O3, TiO2e ZrO2 or Si3N4
vinegar,! Of these, 5i02 or AA'203 are preferably used.

For example, these 5i02 or AIzOs M are formed by high frequency sputtering or vacuum evaporation.

Furthermore, the maintenance MIf of the synthetic resin in the present invention is also important. ! is a polyimide resin that has a surface flattening function to eliminate irregularities on the pixel surface of the color filter layer or surface steps that occur at the boundaries of each RGB coloring element, and a function to prevent transmission of components of the color filter layer, Acrylic resin, alkyd resin, or melamine resin that has good visible light transparency and has no birefringence and hardens at a temperature that does not deteriorate the color filter layer, or a polymer resin layer that hardens under ultraviolet light. used. The retention of this synthetic resin is determined by the flattening function of the color filter layer and the appropriate thickness of the color filter layer. If the thickness exceeds 85 μm, it will take a long time to dry the synthetic resin layer, and it will be difficult to obtain a completely cured layer. For forming this synthetic resin layer, conventional methods such as a transfer method, a roll coater method, and a spinner method can be used.

Furthermore, the color filter layer in the present invention is obtained by mixing a pigment into a photosensitive resin.
JP-A-Sho S! features a color filter layer described in the issue and a photosensitive resin containing dye as a coloring component. −/Tata3≠−
A color filter layer, etc. described in 1. That is, this color layer is made of a resin such as polyvinyl alcohol, casein, or gelatin impregnated with a dye, or an alkyd resin, a polyimide resin, or a melamine resin impregnated with a dye.

Furthermore, the transparent conductive layer in the present invention is made mainly of indium oxide, which is highly transparent, has low resistance, and can be subjected to fine etching, and in particular, indium oxide is used. ! It is preferable to use % by weight.

This transparent guide 1! The layer can be formed by sputtering using a sintered body of indium oxide containing copper oxide as a target, or by reactive sputtering of an indium tin alloy using argon gas containing oxygen.

[For production]

In the present invention, an inorganic second protective layer is formed between the synthetic resin protective layer and the transparent conductive layer, but even if the transparent conductive layer is etched into a fine pattern, the protective layer will not be damaged. Moreover, the insulation between the surface of the transparent conductive layer and the underlying protective layer or color filter layer is good.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2.

Lake Red O (red release agent manufactured by Dainichi Chemical Co., Ltd.) 2MO
! The part is the average degree of polymerization! O0 degree of saponification is mixed with 10 parts by weight of 0 mol polyvinyl alcohol, and 3 parts by weight of the coloring agent in the supernatant part of the obtained mixture and 90 mol% polyvinyl alcohol with an average degree of polymerization so o - A photosensitive resin composition (A) containing 6 mol% of formylstyrylpyridine was prepared. Next, add this solution to ioo
Coat it on a glass substrate (1) of oho X/, 0 homo with a spinner to a film thickness of about 1 μm, dry for 30 minutes, then pattern-expose it through a mask, and then coat the non-E light area with isopropyl alcohol. After selective removal with /lO”
It was heated for 30 minutes to form a dot-shaped filter layer (3) shown in red (R). Similarly, Lionor Green 2
A green photosensitive resin composition fB) containing Y-40IC (a green pigment manufactured by Toyo Ink Manufacturing Co., Ltd.) as a coloring component, and a blue photosensitive resin composition containing 7 Astogen Blue GNPS (a blue pigment manufactured by Dainippon Ink Chemical Co., Ltd.) as a coloring component. Resin composition (C
) to create a dot-shaped green (G) filter layer (3) and blue (B) filter layer (3) in the same way as the red (R) filter layer (3), and form the color filter layer (
3) was formed.

Next, as a retaining layer (4), a product named Hymar (manufactured by Hitachi Chemical Co., Ltd.) was applied to the corner r using a transfer machine using a transfer roller. The coating was applied to a film of 0.6 to 0.7 μm in thickness, and the solvent was evaporated at irq° C. for 0 minutes. The preservation WmC41) of the 5102 film on the polyimide preservation WI (4) is
Targeting quartz glass, the degree of vacuum is JX/
Color filter p in 0-3'rorr argon gas atmosphere! J (formed by known high frequency sputtering without heating a glass substrate with 31. Film thickness is 100A)
The sputtering time was adjusted so that the 5i02 film was /
The entire surface of a glass substrate of 00tnM X / 00mtr was coated. 7 on the glass substrate with such a color film and router
The transparent conductive layer (2), which is an ITO film containing 0% by weight of tin, is coated at 2000'A while maintaining the temperature of the glass substrate (1)/IfO''CK, and has a resistance of 7527 and a transmittance in the visible range of 10. % low resistance conductor 11I! film, and then diluted with hydrochloric acid and distilled water l:2 at a temperature of 110″C.
Using a chemical etching solution for the ITO film, the width between the electrodes is striped to 20 μm so that the parts corresponding to the red, green, and blue pixels in the horizontal direction in Figure 2 are electrically insulated. Transparent with shaped electrode processing? I! If color filter was created.

[Comparison example]

A color filter with transparent electrodes was prepared in the same manner as in the example except that the protective layer (4') was not formed.

As described above, the quality of pattern formation of the transparent electrodes of the color filter with transparent 1tL'1lii obtained in the example and the color filter with transparent electrode obtained in the comparative example was observed using an optical microscope. When observed with an optical microscope, it was confirmed that in Example 1, a sharp pattern could be formed in both the peripheral glass portion and the central color filter portion.

On the other hand, in the color filter prepared in the comparative example, the conductive layer on the glass substrate had a sharp pattern, but in a portion of the color filter, the electrodes were locally thin and only meandering electrodes could be formed.

〔Effect of the invention〕

As described above, since the present invention forms the inorganic second protective layer between the synthetic resin and the transparent conductive layer, the transparent conductive layer can be formed without over-etching or under-etching. can be etched into fine patterns, and will not scratch the protective layer made of synthetic resin.

In addition, in the present invention, the retention of synthetic resin W! ! The layer covers only the color filter layer, and the inorganic second protective layer covers the color filter layer and the surface of the transparent substrate.
The base of the transparent conductive layer becomes an inorganic protective layer of the same quality regardless of the presence or absence of the color filter layer, and the interfacial properties and adhesion between the transparent conductive film and the base are the same, making microfabrication of the transparent conductive layer even easier. be able to. Therefore, the present invention is particularly useful when a multi-panel process is employed in the assembly of so-called liquid crystal display cells, in which a plurality of display areas having color filters are arranged on a relatively large transparent substrate.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, in which FIG. 1 is a longitudinal cross-sectional view of a substrate with a transparent conductive color filter, and FIG. 2 is a longitudinal cross-sectional view of the transparent conductive color filter shown in FIG. A plan view of the attached substrate, FIG. 3, shows an RGB liquid crystal display element using a conventional transparent conductive color filter substrate. Figure 1 Figure 2

Claims (6)

[Claims] (1) A transparent substrate, a color filter layer formed on the surface of the transparent substrate, a synthetic resin protective layer formed to cover the color filter layer, and a transparent conductive layer provided on the protective layer. 1. A transparent conductive color filter-equipped substrate comprising a transparent conductive color filter-equipped substrate comprising: an inorganic second protective layer formed between the synthetic resin protective layer and the transparent conductive layer. (2) The inorganic second protective layer is SiO_2, Al_
2O_3, TiO_2, ZrO_2 or Si_3N_4
The substrate with a transparent conductive color filter according to claim 1, comprising a layer of one type or a mixture of two or more types. (3) The substrate with a transparent conductive color filter according to claim 1 or 2, wherein the synthetic resin protective layer is made of a polymeric organic material such as polyimide resin, acrylic resin, alkyd resin, or melamine resin. . (4) The transparent conductive color filter substrate according to claim 3, wherein the synthetic resin protective layer covers only the color filter layer. (5) the color filter layer is polyvinyl alcohol;
Claims 1 to 4 are products in which a dye is impregnated into a resin such as casein or gelatin, or a pigment is impregnated into an alkyd resin, a polyimide resin, or a melamine resin. Substrate with transparent conductive color filter. (6) The transparent conductive layer is a layer containing 85% to 95% by weight of indium oxide and 5% to 15% by weight of tin oxide. Substrate with transparent conductive color filter.