JP2828796B2 - Manufacturing method of liquid crystal display element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device (hereinafter, referred to as a liquid crystal display device).
More particularly, the present invention relates to a method of manufacturing an LCD in which a plurality of cell containers into which liquid crystal is injected are stacked and sealed under pressure to increase productivity.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional LCD generally used.
3 is a flow chart showing a production process.

As shown in FIG. 1, when manufacturing an LCD on an industrial basis, first, a transparent electrode pattern is divided and formed on the surface of a large glass substrate as an original plate to form a large substrate. The two large substrates are arranged to face each other with a sealing material therebetween, and the two large substrates are joined by hot pressing (Step 1).
Next, the large substrates in the joined state are cut to obtain a large number of cell containers (step 2). In this step, the divided large substrates become the electrode substrates of each cell container. The cell container thus manufactured has a structure in which a sealing material applied in a frame shape is interposed between two electrode substrates, and each cell is inserted through a liquid crystal injection port which is an opening of the sealing material. Liquid crystal is injected into the container (step 3). Thereafter, a sealing material is applied to the liquid crystal injection port in a pressurized state, and the sealing material is cured to seal the liquid crystal in the cell container (Step 4).

As shown in FIG. 6, such pressure sealing is performed collectively in a state in which a plurality of cell containers 1 in which liquid crystal has been injected between opposing electrode substrates 2 and 3 are stacked. A spacer 4 made of paper or the like is interposed between adjacent upper and lower cell containers 1 and 1 to protect the glass surface.

[0005]

By the way, glass powder and glass fragments are generated in the above cutting process.
If these foreign substances such as glass powder adhere to the outer surface of the large substrate (electrode substrate), it cannot be easily removed by ordinary brush cleaning. In some cases, a hard foreign object is interposed between the two. When manufacturing an LCD such as an S-TN type LCD which requires a high dimensional accuracy in a cell gap, pressure sealing is performed in a state where foreign matter such as glass powder is sandwiched between cell containers. However, uneven pressure is likely to occur, resulting in a gap failure, which has led to a decrease in yield. Also, in the polarizing plate attaching step after the pressure sealing, if foreign matter is attached to the outer surface of the electrode substrate, the yield is inevitably reduced.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method of manufacturing an LCD in which the yield is prevented from being reduced due to the adhesion of foreign matter such as glass powder.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to provide a protective film having substantially the same shape as an electrode substrate at a position corresponding to each cell container on the outer surface of a large substrate before performing a cutting step. This is achieved by peeling off the protective film when the liquid crystal injection step is completed, and then performing a pressure sealing step.

[0008]

[Function] If a protective film that can be easily peeled off is provided beforehand in a place where the adhesion of the foreign matter becomes a problem before the cutting step in which the foreign matter such as glass powder is generated, the foreign matter can be removed simply by peeling off the protective film. Since it can be removed, the pressure can be evenly transmitted in the pressure sealing step to avoid a gap failure, and the polarizing plate can be attached to a flat glass surface.

[0009]

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

FIG. 1 to FIG. 4 all show S-
1 is a plan view of a large substrate before a cutting step, FIG. 2 is a side view thereof, FIG. 3 is a plan view of a cell container after the cutting step, and FIG. 4 is a flow chart showing a manufacturing step. It is a chart.

As is apparent from these figures, in this embodiment, if the original plate processing step (Step 1) is completed, the cutting of the outer surfaces of the large substrates 5 and 6 is performed before the cutting step (Step 3) is performed. A film-like protective film 7 that covers the liquid crystal injection region in the same shape as the electrode substrates 9 and 10 of the cell container 8 is adhered to the inside of the line A (step 2). Then, after injecting the liquid crystal into each cell container obtained by cutting (step 4), the protective film 7 is peeled off (step 5), and thereafter, a plurality of cell containers 8 are laminated. The liquid crystal in each cell container 8 is sealed while applying pressure (Step 6). Therefore, the glass powder and glass fragments generated during the cutting process do not adhere to the outer surfaces of the large substrates 5 and 6 where the protective film 7 is coated, in other words, the electrode substrates 9 and 10 In the pressure sealing step, which does not adhere to at least the liquid crystal injection region of the outer surface and thus peels off the protective film 7, foreign matters such as glass powder between the adjacent cell containers 8 in a stacked state are removed. There is no need to worry about being pinched, and the cell container 8 caused by uneven pressure.
Can be avoided. Also, in the polarizing plate attaching step performed after the pressure sealing step, the electrode substrate 9
Since no foreign matter adheres to at least the liquid crystal injection region of the outer surface of the polarizing plate 10, a polarizing plate (not shown) can always be stuck to a flat glass surface.

As described above, in the above-described embodiment, the protective film 7 is adhered in advance to a place where adhesion of foreign matter such as glass powder becomes a problem, and the protective film 7 is peeled off to remove the foreign matter. Since the pressure sealing is performed, the pressure is transmitted evenly at the time of pressurization, so that a gap failure of the cell container 8 can be avoided. As a result, an S-TN type LCD that requires a high gap accuracy is required.
Can significantly improve the production yield. In addition, since the polarizing plate can be attached to the flat glass surface on which the foreign matter does not adhere to the cell container 8 after the sealing, further improvement in the yield can be expected.

In the above embodiment, a film-like protective film is used. Alternatively, an organic resin film which is easy to peel off may be formed on the outer surface of the large substrate and used as a protective film. Good.

The present invention is not limited to the S-TN type LCD, but is also applicable to the manufacture of other LCDs requiring a high gap accuracy, such as ferroelectric LCDs and homeotropic alignment LCDs.

[0015]

As described above, according to the present invention, foreign matters can be removed only by peeling off the protective film provided on the outer surface of the large substrate before the cutting step.
It is possible to avoid pressure unevenness in the pressure sealing step, which causes a gap failure, and to achieve an excellent effect that the production yield is greatly improved. Further, the yield can be improved also in the subsequent polarizing plate attaching step.

[Brief description of the drawings]

FIG. 1 is a plan view showing a large substrate before a cutting step in one embodiment of the present invention.

FIG. 2 is a side view of the large substrate shown in FIG.

FIG. 3 is a plan view showing the cell container after a cutting step in the embodiment.

FIG. 4 is a flowchart showing a production process of the embodiment.

FIG. 5 is a flowchart showing a conventional manufacturing process.

FIG. 6 is a side view for explaining a pressure sealing step.

[Explanation of symbols]

 5,6 Large substrate 7 Protective film 8 Cell container 9,10 Electrode substrate

Claims (1)

(57) [Claims] 1. A large substrate that can be divided into a plurality of electrode substrates
After joining the sheets facing each other, this is cut to produce a plurality of cell containers, and then liquid crystal is injected into each cell container. In the manufacturing process of the liquid crystal display element for sealing the liquid crystal in the cell container, before performing the cutting step,
On the outer surface of the large substrate, a protective film having substantially the same shape as that of the electrode substrate is provided at a position corresponding to each cell container on the outer surface of the large substrate, and the protective film is peeled off at the time when the liquid crystal injection step is completed. A method for manufacturing a liquid crystal display element, comprising performing the pressure sealing step.