JPH04199130A - Production of liquid crystal panel - Google Patents

Abstract

PURPOSE:To facilitate pressing with uniform load and to easily obtain a uniform gap by providing 2nd seals to embrace 1st seals, maintaining a vacuum in the 2nd seals and pressurizing upper and lower substrates with an atm. pressure. CONSTITUTION:The 2nd seals 9 embracing the 1st seals 5 are formed around the upper substrate 2 and the lower substrate 4 and the vacuum state is maintained in the 2nd seals. Glass fibers for forming the gap are incorporated into the sealing materials and the sealing materials are applied by screen printing, etc. A spacing is provided between the substrates 2 and 4 via a black 10 and the cell is installed in a vacuum vessel 11. The block 10 is detached in the vacuum and the substrates are stuck to each other. The vacuum is maintained in the 2nd seals 9 and, therefore, the atm. pressure is applied on the upper and lower substrates 2, 4 to pressurize the substrates and to form the gap when the vacuum is released to the atm. The pressurization with the uniform load is allowed in this way and the uniform gap is formed.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is based on bonding upper and lower substrates to form a gap.
The present invention relates to a method of manufacturing a liquid crystal panel in which the gap is filled with liquid crystal.

Conventional technology The conventional manufacturing method for liquid crystal panels is as follows: Patent application 1986-9
As shown in No. 5660, there is a method of vacuum-packing cells bonded to ζ by sandwiching them from above and below with plate-shaped jigs.

Figure 10! Friend: This is a cross-sectional view of a liquid crystal panel to explain the conventional method of manufacturing the liquid crystal panel.

A color filter 1 is formed on the upper substrate of 2, and a TFT element 3 is formed on the lower substrate of 4. 5
6 is a sealing material for bonding the upper and lower substrates 2.4 together, and 6 is a spacer material for forming a gap between the upper and lower substrates 2.4, and the formed gap is filled with liquid crystal. 7 is a plate-shaped jig for storing the bonded upper and lower substrates 2.4, 8
is a plastic bag for vacuum-packing these items.

FIGS. 11(a) and 11(b) are a plan view and a sectional view of the liquid crystal panel.

The method for manufacturing the conventional liquid crystal panel configured as described above is as follows.

In other words, when forming a gap between the upper and lower substrates 2.4, the sealant 5 is applied to either the upper or lower substrates 2.4, and the upper and lower substrates 2.4 are bonded together before the sealant 5 hardens. It is stored in a plate-shaped jig 7.

This plate-shaped jig 7 prevents contamination of the terminals caused by the pack bag 8 coming into contact with the terminal portions of the board, and positional displacement caused by contacting the ends of the upper and lower boards.

Thereafter, it is inserted into a pack bag 8, deaerated in a vacuum state, and then vacuum packed to form a gap at atmospheric pressure. In this vacuum-packed state, the seal is cured, the pack bag is opened, the panel is taken out, and the process proceeds to liquid crystal filling.

Problems to be Solved by the Invention However, in the above structure, after the upper and lower substrates 2.4 are bonded together, it is necessary to insert them into the plate-shaped jig 7 or the pack bag 8, or to open the vacuum pack or remove the jig. The work is complicated as it requires disassembly.

In addition, pack bags must be reliable in terms of tear resistance, heat resistance, etc., and checking their quality is troublesome.

Furthermore, since the sole material 5 is vacuum packed in an uncured state, the pack bag 8 comes into contact with the upper and lower substrates 2.4, causing misalignment, which is unfavorable in terms of image quality.

Therefore, in the past, a plate-shaped jig 7 was used to prevent large deviations, but due to the fact that the pack bags come into contact with each other during vacuum pressurization, slight deviations occur, and the high positional accuracy of the upper and lower substrates due to future high-density The present invention takes into consideration this problem, and aims to provide a method for manufacturing a liquid crystal panel that is simple and forms a high-precision gap without misalignment without using a pack bag or a jig. Means for Solving the Problems The present invention provides a first group of seal portions forming a liquid crystal filling portion;
an assembly means having a second seal part that engages the first group of seal parts, and forming a gap by evacuating the inside of the second seal part; and a method of releasing the vacuum inside the second seal part after assembly. According to the present invention, according to the above-described structure, by applying atmospheric pressure from the periphery of the upper and lower substrates by making the inside of the second seal part a vacuum,
By creating a vacuum inside the gear knobs of the upper and lower boards and applying atmospheric pressure to the upper and lower boards themselves, uniform loads can be applied without using vacuum bags, simplifying processes such as inserting jigs and pack bags, and bagging jigs. This eliminates defects such as terminal contamination and misalignment that conventionally occur due to contact with bag bags.In the future, as pixel densities and throughputs increase, high-precision LCDs with good productivity will be used. A plan view of a liquid crystal panel for explaining a first embodiment of the method for manufacturing a liquid crystal panel of the present invention. In the following, we will explain the manufacturing method of the liquid crystal panel shown in the same figure.
Even if a second seal 9 is formed that embraces the first seal 5, the inside of this second seal is in a vacuum state, and the upper substrate 2 and the lower substrate 4 are separated by the spacer 6 with a uniform gap of 5 μm due to atmospheric pressure. Even if ±0.1 μm is formed, the same material can be used for the seals 5 and 9. For example, liquid epoxy adhesive, two-component poxy adhesive, rough UV
In addition to using adhesives, this sealing material, which contains glass fibers (not shown) for gap formation, can be applied to the upper and lower substrates by screen printing or application with a dispenser. Form either 2 or 4.

Second best method A certain force is used to bond the upper substrate 2 and lower substrate 4 together (first, a gap is provided between the substrates 2 and 4 via the block 10).

Thereafter, the block 10 is placed in a vacuum container 11, the inside of the container 11 is degassed, the block 10 is removed in a vacuum, and the substrates are bonded together.

After that, when the vacuum is leaked to the atmosphere, atmospheric pressure is applied to the upper and lower substrates 2 and 4 due to the vacuum inside the second seal 9, and although the pressure is applied and a gap is formed, it is suboptimal.The positions of the upper and lower substrates 2 and 4 are corrected. After that, the first and second seals 5.9 of this panel are cured in a heating oven, etc., and then the upper and lower substrates are cut with enough force to be cut as shown in Fig. 3. 2. Create a scribe line 12 at the same position as in 4 and press it with a roller or the like (not shown) to cut it.

As described above, according to this embodiment, the second seal 9 that engages the first seal 5 is provided, and by making the inside of the second seal 5 a vacuum and pressurizing the upper and lower substrates at atmospheric pressure, a uniform load is applied. A uniform gap can be easily obtained.

Next best embodiment A second embodiment of the present invention will be explained with reference to FIG.

If the viscosity of the sealing material used here is low, when the inside of the second seal 9 is vacuumed and the substrate is pressurized at atmospheric pressure, the second seal 9 will flow into the panel.

In this embodiment, this problem is solved by temporarily curing only the second seal 9 before bonding. Cover it with a mask 14 (only the second seal 9 is irradiated with UV from the UV lamp 15 to perform temporary curing.

In this state, even if vacuum pressure is applied after bonding, the sealing material will not flow inside the panel where the viscosity is high.Next, a third embodiment will be explained with reference to FIG. Sumo second sticker 9
The purpose of this is not to bond the upper and lower substrates, but to attach the second seal 9.
The purpose is to create a vacuum inside.Therefore, the second seal 9 is likely to peel off from at least one of the upper and lower substrates 2 and 4 that it is in contact with. A thin film 16 (eg, chromium or aluminum) is formed in advance.

When the adhesive force of the second seal 9 is strong when cutting and removing the second seal 9, the cutting line at the scribe line is disturbed at the cross section with the seal part. Since it is weak, such a phenomenon is eliminated and the cutting accuracy is improved. Next, a fourth embodiment will be explained with reference to FIG. 6. The first seal 5 is formed on the upper substrate 2 L, the second seal 9 is formed on the lower substrate 4 Even in this case, vacuum pressurization is possible, and it is also possible to use different materials for the first and second seals 5.9.

This (U) generally has weak adhesive strength but short curing time.
1. Use V-resin material or high viscosity grease with almost no adhesive strength for the second seal 9. X. By using an epoxy adhesive with strong adhesive force for the first seal, the curing operation time can be shortened and the cutting precision can be improved. Next, a fifth embodiment will be explained with reference to FIG. 7. Opening 17 in at least a portion of second seal 9
The upper and lower substrates 2.4 are bonded together in the atmosphere.

At this time, the upper and lower substrates 2.4 are aligned with high precision.

After that, the inside of the second seal 9 is degassed in a vacuum container and immediately removed.
A sealing material 18 (for example, a UV-resistant resin epoxy adhesive) is applied to the opening 17 to seal it.

By then leaving the panel in an atmospheric atmosphere,
In this embodiment, the upper and lower substrates 2 and 4 are exposed to atmospheric pressure and a predetermined gap is obtained. When the opening 19 of the second seal 9 is configured with a step as shown in FIG.
Next, a sixth embodiment of the present invention will be described with reference to FIG. 9. The first and second seals 5 and 9 are hardened. After that, before cutting and removing the second seal 9, a laser beam 20 (for example, a YAG laser that passes through the glass substrate and evaporates only the sealing material, focused by a lens 21) is used to cut the second seal 9. By irradiating a part of the glass to cause it to burst and leak the vacuum inside the panel to the atmosphere, it is possible to prevent minute glass chips that occur during cutting from entering the panel. Explanation Table 3 Depending on the material used for the crushed crystal panel, there are some forces that can cause image quality deterioration due to the evaporation of gas from the sealing material caused by the laser beam. According to the present invention, it is possible to reliably prevent glass chipping from entering the liquid crystal layer, which affects the image quality, and to uniformly form the gap in the liquid crystal layer that affects the image quality with a simple structure. The practical effect is that a panel with high positional accuracy of the board can be obtained.

[Brief explanation of the drawing]

FIGS. 1(a) and 3(b) are a front view and a cross section of a liquid crystal panel for explaining the first embodiment of the method for manufacturing a liquid crystal panel of the present invention. )j;L Process description of the same embodiment Fig. 4 is a cross-sectional view of a liquid crystal panel for explaining the second embodiment of the present invention Fig. 5(a),
(b) (Yo) A front view and a sectional view of a liquid crystal panel for explaining a third embodiment of the present invention. FIG. 6 (Yo) A sectional view of a liquid crystal panel for explaining a fourth embodiment of the present invention. 7
Figure (a). (b)j;L The front view and cross section of a liquid crystal panel for explaining the fifth embodiment of the present invention are shown in FIGS. 8(a) and (b).
? ;L Front view and cross-sectional view of a liquid crystal panel for explaining the sixth embodiment of the present invention FIGS. 9(a) and (b) it
A front view and a cross-sectional view of a liquid crystal panel for explaining the seventh embodiment of the present invention. FIG. In the front view and cross-sectional view of the liquid crystal panel, 1...color filter, 2...upper substrate 3...
・TFT element, 4... Lower substrate, 5... First seal/k 6... Spacer 9... Second seal,
10... Block 11... Vacuum container 12, 13.
...Scribe line, 14...Masuku 15...
UV lamp, 16... Thin trap 17, 19... Opening 18... Sealing material, 20... Name of Laser 9 agent Patent attorney Akira Kokaji and 2 others 9-11 2 Seal (a) (b) Figure 2 Figure 3 114! ! l/Seal 5! Figure 9 ((1”) Figure 11 (b)) \gi 4

Claims (7)

[Claims] (1) A first seal that forms a liquid crystal filling part on upper and lower substrates having a predetermined gap and a plurality of opposing electrodes, a second seal that joins this first seal, and a second seal that is arranged inside the second seal. 1. A method for manufacturing a liquid crystal panel, comprising: assembling means for creating a gap by applying a vacuum; and removing means for removing second seals of the assembled upper and lower substrates. (2) The method for manufacturing a liquid crystal panel according to claim 1, wherein the gap is formed after only the second seal is temporarily cured. (3) The method for manufacturing a liquid crystal panel according to claim 1, further comprising forming an overcoat material that weakens adhesive strength on at least one of the upper and lower substrates at which the second seal is applied. (4) The method for manufacturing a liquid crystal panel according to claim 1, wherein the first and second seal materials are different, and the second seal has a weaker adhesive force than the first seal. (5) The method for manufacturing a liquid crystal panel according to claim 1, wherein at least a portion of the second seal portion has an opening, and the opening is sealed in a vacuum. (6) The method for manufacturing a liquid crystal panel according to claim 1, further comprising curing the first and second seal portions and then removing the second seal using a laser. (7) The method for manufacturing a liquid crystal panel according to claim 1, wherein the second seal removal is performed in a vacuum.