JPH0545637A - Smoothing method and smoothing material for base body surface - Google Patents

Abstract

PURPOSE:To facilitate a rubbing treatment by previously transferring intrinsically generated rugged parts with another base body having the same ruggedness and further removing the freshly generated rugged parts by a photoetching method, thereby smoothing these parts. CONSTITUTION:A curable org. resin 3 is applied on the surface of a base body 1 provided with color filters 2 by a roll coater method, etc., and is left standing to dry and cure. This resin is then pressed by another base body 11 provided with rugged level difference 12, by which the rugged shapes are transferred. The curable resin 3 is deformed by transfer to the rugged shapes having the level difference of a surface A and a surface B. After the resin is strongly cured at a high temp., a transparent electrode 4 is provided over the entire surface and the parts D of the projecting parts are removed by a photoetching method to flatten the surface C and the surface B at the same level. The rubbing treatment can, therefore, be smoothly executed and the generation of dust by the cutting of the fibers of a rubbing cloth and the dust by cutting of a part of the level differences is decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the smoothing of the surface of a substrate used in a liquid crystal display panel for laptop and notebook computers.

[0002]

2. Description of the Related Art A liquid crystal display device is normally operated by arranging liquid crystal molecules between electrodes formed on two upper and lower substrates facing each other and controlling a voltage applied between these electrodes.
At least one of the upper and lower electrodes used at this time is a light transmissive electrode (hereinafter referred to as a transparent electrode). Generally, a sectional view of a substrate portion of a panel of a liquid crystal display device has a structure as shown in FIG. 6 without mentioning a conventional example. That is, when a transparent electrode formed on a substantially uniform and flat substrate is observed in detail, unevenness is generated between the transparent electrode and the substrate by this film thickness, and a step is formed. In order to control the alignment of liquid crystal molecules, an alignment film material such as polyimide resin, which facilitates alignment, is applied to a substrate including an electrode having a thickness of about 0.1 micron, but the degree of unevenness does not change. Then, a step remains on the substrate. In the prior art, a rubbing treatment was performed with a cloth made of nylon or rayon as a pretreatment for aligning the liquid crystal molecules in such a stepped state.

[0003]

When there is a step between the substrate and the transparent electrode, the fibers of the rubbing cloth are cut and left on the surface as dust during the rubbing process, or a part of the step is present. Is scraped off and remains on the surface as dust. Then, these dusts that have once remained on the surface cannot be sufficiently removed even if they are treated by the fine dust cleaning method used in semiconductors such as brush cleaning in the next cleaning step, ultrasonic cleaning, megahertz band cleaning, and fluorocarbon cleaning. Therefore, when the liquid crystal molecules are arranged, there is a problem that alignment disorder occurs, and further, there is a problem that alignment disorder of liquid crystal molecules occurs at a boundary surface with a step, and display unevenness at the time of display due to these causes,
There is a problem that color unevenness, pinholes, electrical shorts, etc. are likely to occur and display quality is degraded.

[0004]

The present invention is intended to solve such a problem by eliminating a step due to unevenness between the substrate and the electrode and flattening the step.

[0005]

[Function] Since the base and the electrode are flat with no steps on the surface, the rubbing process can be performed smoothly, and the generation of dust due to cutting of the fibers of the rubbing cloth and dust due to partial scraping of the step are significantly reduced. To do. Then, the alignment disorder of the liquid crystal molecules is also reduced at the interface between the substrate and the electrode.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (FIGS. 1) to (FIG. 5) are process flow charts for explaining the present invention, each showing a sectional view composed of a substrate, electrodes and the like. FIG. 1 shows a cross-sectional view in which an acrylic curable resin 3 is applied to the surface of a glass plate 1 or a plastic plate 1 provided with a color filter 2 by a roll coater method or a spin method and then dried and cured by leaving it to stand. Another substrate 11 provided with an uneven step 12 having an E surface and an F surface having a step of approximately 0.2 μm as shown in FIG.
A process cross-sectional view in which the uneven shape is transferred by pressing is shown in FIG. At this time, instead of using a flat plate as another substrate, it is also possible to transfer with a substrate having a predetermined unevenness on the surface of the cylindrical roller. In FIG. 3, reference numeral 31 indicates that the acrylic curable resin 3 has been deformed into a concavo-convex shape having steps on the surfaces A and B by the transfer. Then 1
A process in which the transparent electrode 4 is provided on the entire surface so as to have a film thickness of approximately 0.2 micron by a vacuum deposition method such as a sputtering method or an electron beam method after being strongly cured at a high temperature of 50 to 200 degrees for about 1 hour. A sectional view is shown in (FIG. 4). In the figure, the unevenness of the surface C and the surface D is 0.2 micron. Next, the D portion of the convex portion in FIG. 4 is removed by the photoetching method to make the C surface and the B surface flush with each other and flattened (FIG. 5). From (Figure 1) to (Figure 5) R,
G and B are red, green, and blue of the color filter, respectively, and BL corresponds to black provided on the boundary of each color. The thickness of color filter and black is 1-2 microns,
The width is accurate to 90 microns and 20 microns, respectively, and the length of one line is about 20 to 30 cm. Transparent electrode 4
There are electron beam vapor deposition, sputter vapor deposition, etc., but in the case of sputter vapor deposition, a vacuum degree of 0.
1-0.5 Pascal, substrate temperature 150-200 degrees, and sputter rate 5-7 A / sec. The target composition ratio was indium oxide: tin oxide = 90: 10. In the photolithography process, a hydroiodic acid solution was used as an etching solution.

The key point of the present invention is the smoothing of the surface by applying the method of transferring the irregularities of another substrate, and the conditions for forming the transparent electrode, the accuracy of the color filter, and the photoetching conditions are the same as those described here. It is not limited.

[0008]

As described above, according to the present invention, the same unevenness and shape originally existing on the substrate are once provided on another substrate, then transferred, and then the protrusions are removed by etching to remove the substrate. By flattening the electrode part and the electrode part on the same surface, the rubbing process after the application of the alignment film material can be carried out very smoothly, and the dust caused by cutting the rubbing cloth at the time of the rubbing process, and the influence of dust due to the scraping of the protrusions It is expected that the effect of reducing the liquid crystal display panel and improving the display quality and yield of the liquid crystal display panel can be expected.

[Brief description of drawings]

FIG. 1 is a sectional view of an original substrate in which a resin is applied on a glass substrate provided with a color filter.

FIG. 2 is a sectional view of another base body.

FIG. 3 is a sectional view transferred to the original substrate.

FIG. 4 is a sectional view in which a transparent electrode is provided.

FIG. 5 is a sectional view in which a part of the transparent electrode is removed.

FIG. 6 is a sectional view of a base portion of a panel of a conventional liquid crystal display device.

[Explanation of symbols]

 1 Glass Plate 2 Color Filter 3 Organic Resin 4 Transparent Electrode 11 Different Substrate (Glass Plate) 12 Concavo-convex Part 31 Transferred Organic Resin

Claims (3)

[Claims] 1. A curable organic resin is applied on a substrate, and the organic resin is pressed by another substrate having an uneven shape on the surface to transfer the uneven shape. Then, thin film electrodes are laminated and photolithography is performed. A method for smoothing the surface of a substrate, characterized in that the convex portions of the thin film electrode are removed by the method. 2. A smoothed product on the surface of a substrate produced by the smoothing method according to claim 1. 3. The substrate according to claim 1 or 2, wherein the other substrate having an uneven surface is a cylindrical roller or a flat plate,
A method for smoothing a substrate surface or a smoothed product, which is characterized in that the uneven shape is transferred by these.