JPS60262129A - Manufacture of substrate for liquid-crystal display device - Google Patents

Abstract

PURPOSE:To improve the productivity by transferring a solution of a mixture of an orienting agent and resin beads to a surface plate or a mesh on a roller surface and then transferring it to a flexographic plate, and transferring it to a bae for the display device and fixing dried beads on an oriented film. CONSTITUTION:The solution 23 obtained by mixing resin beads with the orienting agent is applied uniformly by using a mesh doctor blade 22 formed on the surface of the surface plate 21. Then, a plate cylinder 24 is rolled on the surface plate 21 to transfer the bead mixed solution 23 to the flexographic plate 25 supported on the surface of the plate cylinder 24. Further, the plate cylinder 24 is rolled to retransfer the resin bead mixed orienting agent 23 on the flexographic plate 25 to a glass base 27 on a prepared printing base 26. Then, the glass base 27 is placed in a furnace, and dried and baked to form the oriented film. Consequently, the substrate where resin beads are fixed with the oriented film is manufactured with good productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for manufacturing a substrate for a liquid crystal display in which resin beads are fixed to a dispersion/alignment film as spacers.

B) Prior Art Conventionally, in a liquid crystal display in which a liquid crystal is sandwiched between a plurality of substrates, spacers are dispersed in order to keep the thickness of the liquid crystal constant. For example, JP-A-58-14
Publication No. 2316 states that by fixing with this spacer alignment film, the spacer can be used without wasting it, and furthermore, the spacer does not move even if surface treatment (orientation treatment) is performed after fixation, which is preferable. However, in this publication, since an inorganic material is used as the spacer, there are the following drawbacks depending on the temperature. That is, if the liquid crystal is injected and sealed at room temperature, at relatively high temperatures (50 to 60"O), an inorganic spacer (151 (15
1 and the one-sided substrate (11) are separated from each other. Also low temperature (0~-
60°C), the container volume is kept constant by the inorganic spacer cts (151), but the volume of the liquid crystal u7 becomes smaller, so the area where there is no liquid crystal (
17) '2>E occurs. Since a liquid crystal display uses the electro-optical characteristics of liquid crystal, the area fin' where no liquid crystal is present is displayed as a black smudge, which is inconvenient.

In order to solve this problem, it was found that it was possible to use organic polymer material gold as a spacer, but the spinner method was applied as a method for applying an alignment agent containing spacers made of organic polymer material (hereinafter referred to as resin beads). I also realized that I couldn't do it.

In other words, the alignment film needs to have a thickness of 5,000 or less due to its optical properties (thickness conditions are the same as conventional ones), but if applied using the spinner method, although the film thickness condition is met, since the spacer is also included in the alignment agent, the spacer may crack. It is necessary to prevent the spacers from concentrating on one periphery and clumping together. Furthermore, if the spacers can be uniformly distributed, they will cover the entire surface of the board, so there will be no misalignment in undesirable areas such as terminals or seals. Since the film and spacer must be removed, the process becomes complicated and inconvenient.

8) Object of the Invention In consideration of the above-mentioned points, the present invention provides a highly productive method for manufacturing a substrate for a liquid crystal display using an alignment agent mixed with resin beads.

2) Structure of the Invention The present invention is directed to manufacturing a substrate using flexographic printing technology, particularly by forming the surface of a surface plate or roller before transfer with a mesh-processed surface. This achieves uniform application of the alignment agent mixed with resin beads.

E) Embodiment FIG. 1 is a sectional view of a liquid crystal display according to the present invention, and +IH1
1 is a glass base (21 (2+) with an electrode +31 (31
and an alignment film (41 (41t-).A substrate with an alignment film (
41 (Resin beads (51F51) are fixed as spacers to 41.F61 (61 is a seal that is attached to the substrate (lllli) to form a container for holding the liquid crystal, (7
) is a nematic liquid crystal.A liquid crystal display of X2011 made of resin beads as a spacer and divinylhenzene polymer or benzoguanamine resin as 5H51 was made and left in a constant temperature bath at -40°C for 240 hours, but the liquid crystal No non-existing areas occurred.

A method for manufacturing a liquid crystal display substrate for manufacturing such a liquid crystal display will be described.

#! FIG. 2 is a schematic diagram of a printing apparatus for a liquid crystal display substrate by flexographic printing according to an embodiment of the present invention. The printing solution used is an alignment agent (alignment film precursor dissolved in a solvent) mixed with resin beads.
Apply the resin bead-containing alignment agent (231) uniformly onto the surface of the plate cylinder (24) using a doctor blade (221T). (The image is transferred to the flexo plate (c) supported on the surface of the plate 241. Then, the plate cylinder @ is rotated and the glass base plate (241)
Re-transfer the alignment agent mixed with resin beads on the flexo plate (total) to 0. Thereafter, the glass base (27) is placed in a T-furnace and dried or fired to form a film of the alignment agent, thereby obtaining an alignment film. Whether drying, baking, or both are performed depends on the film forming conditions of the alignment agent. Figure 3 is a schematic diagram of another example of flexographic printing, in which resin beads are placed between the anilox a-ra 3υ and the doctor roller (to). By accumulating the mixed alignment agent and rotating both rollers anc0, an alignment agent lI equivalent to the liquid film on the surface plate υ is obtained. is formed on the surface of the anilox roller. Therefore, by rotating the plate cylinder nt close to this, the orientation agent mixed with resin beads is transferred from the anilox roller rotation to the flexographic plate (to), and the printing plate (to), which moves in synchronization with this rotation, is transferred to the flexo plate (to). Re-transfer onto the glass base (b) above (to).

Both of the above two examples were made based on the fact that even if the glass base is hard, partial printing can be done if the flexographic plate is soft, and the process is similar to flexographic printing. Very similar to known techniques. However, unlike ink printing, it was difficult to achieve uniform printing in both cases of printing using an alignment agent mixed with 9 resin beads. That is, in the example shown in Figure 2, the resin beads are scraped off by the doctor blade,
In the example shown in FIG. 3, the resin beads remain in the liquid reservoir due to the doctor roller, so printing cannot be performed with the resin beads dispersed in a predetermined amount. There, the surface plate (21
When mesh processing was performed on the surface of the anilox roller (B) 1 or the anilox roller (B), uniform printing was achieved, which will be explained below.

There are three types of printing defects with resin bead-containing alignment agent: as shown in Figure 4, there is a cut a2 in the alignment agent (solution) (transfer) (9), and (transfer) in the resin beads... There are cases where the amount of resin beads becomes extremely small, and cases where the resin beads locally clump and form clumps.

When we investigated the relationship between the mesh processing provided on the surface of the surface plate and the anilox roller Ill and such defects, we found the following table.

In this table, aggregation refers to resin 11 as described above:
As shown in the table, it means that the bead clumps were seen above the groove of the glass base.
00 mesh/1 nch''), printing was almost good.

In addition, a surface plate and an anilox roller 8 are also used for flexographic printing.
When a mesh of the same size as No. 11 was provided, the above effects were stably obtained and the production yield was improved.

f) Effects of the Invention As described above, the present invention provides a first method in which the entire surface of a solution obtained by mixing resin beads into an alignment agent is coated approximately evenly on the surface of a mesh-processed surface plate or (anilox) roller. a second step of transferring from the surface plate or roller to a solution T flexographic plate, and transferring from the flexographic plate to a display base, and drying and/or low-temperature baking of the transferred display base to form a resin. Since this method of manufacturing a substrate for a liquid crystal display obtains a substrate on which beads are fixed with an alignment film, a substrate having resin beads fixed with an alignment film can be manufactured with high productivity.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a liquid crystal display according to the present invention, Figures 2 and 6 are schematic diagrams of a printing device for a liquid crystal display substrate according to an embodiment of the present invention, and Figure TS4 shows the state of the printed alignment agent. FIG. 5 fal (b), which is a plan view of a main part for explanation, is a schematic cross-sectional view of a conventional liquid crystal display. fil(11...Substrate (21C21...Glass base +31(31...Electrode (41(41...Alignment film) (51(51...Resin beads (6)(6)...
・Seal (7)... Nematic liquid crystal ta... Surface plate... Doctor blade C231 (g)...
Aligning agent mixed with resin beads (241 (B)...Plate cylinder 4 (To)...Flexo plate (261 (To)...Printing stand (2η (B)...Glass base Applicant Sanyo Electric Co., Ltd. One outside representative of the company: Shizuo Sano, patent attorney Figure 1 Figure 5 (a) (b)

Claims (1)

[Claims] 1) A first step in which a solution obtained by mixing a resin piece into an alignment agent is applied approximately evenly onto the surface of a surface plate or roller whose surface is mesh-processed, and the solution is applied from the surface plate or roller to a flexographic plate. The second process involves transferring the resin beads from the flexographic plate to the display base, and drying and/or low-temperature baking of the transferred display base to obtain a substrate on which the resin beads are fixed by the alignment film. Features: Manufacturing method for LCD display substrates