JPH08297290A - Liquid crystal injecting device and production of liquid crystal panel - Google Patents

Abstract

PURPOSE: To eliminate the need for an impurity adsorption layer by providing a vacuum chamber with a tray therein, alternately disposing one electrode plates and other electrode plates formed with ion adsorption layers on the surfaces in juxtaposition within the tray, injecting liquid crystals into the tray and impressing voltages between both electrode plates. CONSTITUTION: The tray 2 is arranged in the lower part in the vacuum chamber and the liquid crystal material 13 is admitted into the tray 2. Empty cells are erected above the tray 2 in such a manner that the side disposed with liquid crystal material injection holes exist in the lower part to immerse the liquid crystal material injection holes into the liquid crystal material 13 in the tray 2. The respective planar bodies are alternately disposed. Further, the ion adsorption layers are formed on the surfaces of the planar bodies of the respective electrodes 14, 15. The bottom of the tray 2 is provided with a passage hole 16 for replenishing the liquid crystal material 13. The removal of the ion impurities in the liquid crystal material 13 by using the tray 2 is executed by impressing a voltage of <=500V between the electrodes 14 and 15 and adsorbing the ion impurities, etc., on the surface of the ion adsorption layers of the planar bodies.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal injection device and a method for manufacturing a liquid crystal panel using the liquid crystal injection device.

[0002]

2. Description of the Related Art Although an STN type liquid crystal panel has been rapidly accepted in the market, this liquid crystal panel has a structure in which a liquid crystal layer is sandwiched between two glass substrates.

However, in the liquid crystal panel having this structure, there is a problem in that a spot-shaped portion having a threshold voltage different from that of other portions is generated by continuous lighting.

As a result of extensive studies on this problem, it has been clarified that ionic impurities contained in the liquid crystal material are adsorbed on the electrodes, and the apparent threshold values differ accordingly.

Therefore, in order to solve this problem, it has been proposed to provide an impurity adsorption layer in a portion other than the electrode (see Japanese Patent Laid-Open No. 97127/1992).

[0006]

However, even with the above proposal, the threshold voltage may vary in a spot shape due to the ion impurities that are not completely adsorbed in the impurity adsorption layer and still remain. all right.

Moreover, there is a problem that the manufacturing cost is increased by providing the impurity adsorption layer.

Therefore, an object of the present invention is to remove ionic impurities in the process of injecting a liquid crystal material into a liquid crystal panel,
This makes it possible to provide a liquid crystal material in which ionic impurities do not remain as compared with conventional ones, and as a result, to provide a high-performance liquid crystal panel in which the threshold voltage does not fluctuate in a spot shape.

It is another object of the present invention to provide a liquid crystal panel which is low in cost without providing the above-mentioned impurity adsorption layer.

[0010]

The liquid crystal injecting apparatus of the present invention is provided with a dish in which a liquid crystal material is placed in a vacuum chamber, and a plurality of one electrode plate and the other electrode plate having an ion adsorption layer on the surface are alternately dished. It is characterized in that they are arranged inside each other, a liquid crystal material is injected into the dish, and a voltage can be applied between the both electrode plates.

Further, the method of manufacturing a liquid crystal panel of the present invention is characterized in that the liquid crystal material is injected into the empty cell by the following steps A to F. Step A: A square or rectangular display area is provided by forming transparent electrode patterns on one transparent substrate and the other transparent substrate. Step B: The adhesive is applied to the filament along the periphery of the display area on one transparent substrate to provide a sealing member, and
A part of the seal member is cut out. Step C: One transparent substrate and the other transparent substrate are bonded together via a seal member, and a liquid crystal material injection hole is formed in the seal member to form an empty cell.

[0012] Step D: Liquid crystal material is injected into the dish, and a voltage is applied between one electrode plate and the other electrode plate.
In the liquid crystal injection device, the empty cell is erected on the dish so that the side where the liquid crystal material injection hole is arranged is the lower side, and after evacuating the vacuum chamber, the liquid crystal material injection hole is immersed in the liquid crystal material in the dish. . Step E: An inert gas is introduced into the vacuum chamber, and the liquid crystal material is injected into the empty cell through the liquid crystal material injection hole. Step F: The liquid crystal material injection hole is sealed with an adhesive resin.

[0013]

In the liquid crystal injecting apparatus of the present invention, a plurality of one electrode plate and the other electrode plate having the ion adsorption layer formed on the surface thereof are alternately arranged side by side in the dish, and the liquid crystal material is placed in the dish. By injecting and applying a voltage between the both electrode plates, ionic impurities can be removed from the liquid crystal material. As a result, the ionic impurities can be removed during the process of injecting the liquid crystal material into the liquid crystal panel, whereby a liquid crystal material having no ionic impurities in advance can be obtained.

According to the liquid crystal panel manufacturing method of the present invention, in the step D using the liquid crystal injection device of the present invention,
A liquid crystal material is injected into the dish, and a voltage is applied between one electrode plate and the other electrode plate to prepare a liquid crystal material free of ionic impurities in advance, and then an empty cell is provided on the dish with a liquid crystal material injection hole. The liquid crystal material injection hole is immersed in the liquid crystal material in the dish after evacuating the inside of the vacuum chamber.
Liquid crystal material without ionic impurities can be injected into the liquid crystal panel.

Therefore, according to the liquid crystal injection apparatus of the present invention and the method of manufacturing a liquid crystal panel of the present invention using the same, it is possible to provide a high-performance liquid crystal panel in which the threshold voltage does not fluctuate in a spot shape, and moreover, the above-mentioned impurities. Since no adsorption layer is provided, a low-cost liquid crystal panel can be provided.

[0016]

1 is a schematic view showing a schematic configuration of a liquid crystal injection device 1 of the present invention, and FIGS. 2 and 3 are a schematic side view and a schematic top view showing a main part (dish 2) of the liquid crystal injection device 1, respectively. It is a figure. FIG. 4 is a plan view of the empty cell 3 according to the method of manufacturing a liquid crystal panel, and FIG. 5 is a cross-sectional view of the empty cell 3.

First, the structure of an empty cell 3 for a monochrome liquid crystal panel manufactured in steps A to C is shown in FIGS.
This will be described below. The empty cell 3 is composed of two glass substrates 4 and 5 made of soda lime glass as the transparent substrate.
Is adhered with a sealing member 6 made of epoxy resin, and many spacers 7 made of spherical resin are arranged in an inner region surrounded by the sealing member 6, and this inner region forms a display region 8. . Seal member 6
Is cut out to form a liquid crystal material injection hole 9. ITO transparent electrodes 10 and 11 are arranged on the inner main surfaces of the glass substrates 4 and 5, respectively. These ITO transparent electrodes 1
0 and 11 are arranged so as to be orthogonal to each other, an alignment film (not shown) is formed thereon, and the surface of this alignment film is rubbed to set the orientation of liquid crystal molecules in a predetermined direction.

Next, the structure of the liquid crystal injection device 1 will be described with reference to FIGS. According to FIG. 1, a dish 2 is arranged below the vacuum chamber 12 capable of depressurizing, and the liquid crystal material 1 is placed in the dish 2.
Contains 3. The empty cell 3 is erected on the plate 2 so that the side where the liquid crystal material injection hole 9 is arranged is downward, and the liquid crystal material injection hole 9 is immersed in the liquid crystal material 13 in the plate 2. . The vacuum chamber 12 is also provided with a mechanism for introducing an inert gas such as argon, but it is omitted in the figure.

Electrodes 14 and 15 facing each other are provided upright inside the dish 2 shown in FIGS. For each of the electrodes 14 and 15, a plurality of plate-shaped bodies are arranged side by side in a comb-like shape, and the plate-shaped bodies are alternately arranged. Further, the interval between the plate-shaped bodies is set to 100 μm, for example. Furthermore, each electrode 14, 1
An ion adsorption layer (not shown) is formed on the surface of the plate-shaped body of No. 5, and this ion adsorption layer is, for example, a SiO layer,
It is provided by the sputtering method. A passage hole 16 for replenishing the liquid crystal material 13 is provided at the bottom of the dish 2.

In order to remove the ionic impurities in the liquid crystal material 13 using the dish 2 having the above-mentioned structure, a voltage of, for example, 500 V or less is applied between the electrodes 14 and 15 to apply a voltage to the surface of the ion adsorption layer of each plate. This can be achieved by adsorbing ionic impurities. According to the experiments conducted by the present inventors repeatedly,
It was confirmed that when the electric field between the electrodes 14 and 15 was set to 5 × 10 ⁶ [V / m] or more, ion adsorption worked sufficiently.

According to the experiments conducted by the present inventor, it was confirmed that the applied voltage up to 1500 V can be used without any adverse effect. In this example, the distance between the counter electrodes is 100 μm.
Therefore, when a high voltage is applied, the liquid crystal material causes dielectric breakdown.

Next, a method of manufacturing a liquid crystal panel using the liquid crystal injection device 1 having the above structure will be described in detail.

By forming the transparent electrode patterns 10 and 11 on the glass substrates 4 and 5 of process A , a square or rectangular display region 8 is provided.

The sealing resin 6 is provided by applying the adhesive resin to the filament along the periphery of the display area 8 on one of the B substrate glass substrates 4 and 5. Further, when the seal member 6 is provided, a part thereof is cut out.

A large number of spacers 7 are sprinkled between the C process glass substrates 4 and 5, and they are attached to each other via a seal member 6, and a liquid crystal material injection hole 9 is formed in the seal member 6 to form an empty cell 3. .

Using the liquid crystal injecting device 1 in which the ionic impurities in the liquid crystal material 13 in the D process dish 2 have been removed beforehand, the empty cell 3 is placed on the dish 2 so that the side on which the liquid crystal material injecting hole 9 is arranged is downward. The liquid crystal material injection hole 9 is erected and immersed in the liquid crystal material 13 in the dish 2.

An inert gas such as N ₂ gas or a rare gas is introduced into the vacuum chamber 12 of process E , and the liquid crystal material 13 in the dish 2 is injected into the empty cell 3 through the liquid crystal material injection hole 9.

The F step liquid crystal material injection hole 9 is sealed with an adhesive resin such as an ultraviolet curable resin.

Thus, in the above-mentioned manufacturing method, in the step D using the liquid crystal injection device 1, a voltage is applied between the electrodes 14 and 15 to preliminarily prepare a liquid crystal material free of ionic impurities, and then the liquid crystal material free of ionic impurities is emptied. It can be injected into the cell 3.

The present invention is not limited to the above embodiments, and various changes and improvements may be made without departing from the scope of the present invention.

[0031]

As described above, according to the liquid crystal injection device of the present invention, it is possible to remove the ionic impurities from the liquid crystal material by the combination of the one electrode plate and the other electrode plate having the ion adsorption layer formed on the surface thereof. In the process of injecting the liquid crystal material into the liquid crystal panel, ionic impurities can be removed, and as a result, a liquid crystal material free of ionic impurities can be prepared in advance.

According to the liquid crystal panel manufacturing method of the present invention, in the step D using the liquid crystal injection device of the present invention,
Liquid crystal material without ionic impurities can be injected into the liquid crystal panel.

Therefore, according to the liquid crystal injecting apparatus of the present invention and the method of manufacturing a liquid crystal panel of the present invention using the same, it is possible to provide a high-performance liquid crystal panel in which the threshold voltage does not fluctuate in a spot shape, and moreover, the above-mentioned impurities. Since no adsorption layer is provided, a low-cost liquid crystal panel can be provided.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a schematic configuration of a liquid crystal injection device in an example.

FIG. 2 is a schematic side view showing a main part of a liquid crystal injection device according to an embodiment.

FIG. 3 is a schematic top view showing a main part of a liquid crystal injection device in an example.

FIG. 4 is a schematic plan view of an empty cell.

FIG. 5 is a schematic sectional view of an empty cell.

[Explanation of symbols]

 1 Liquid crystal injection device 2 Dish 3 Empty cell 4, 5 Glass substrate 6 Sealing member 7 Spacer 9 Liquid crystal material injection hole 10, 11 ITO transparent electrode 12 Vacuum tank 13 Liquid crystal material

Claims (2)

[Claims] 1. A dish in which a liquid crystal material is placed is provided in a vacuum chamber, and a plurality of one electrode plate and another electrode plate having an ion adsorption layer formed on the surface thereof are alternately arranged side by side in the dish, A liquid crystal injection device in which a liquid crystal material is injected and a voltage can be applied between the two electrode plates. 2. A method of manufacturing a liquid crystal panel, characterized in that a liquid crystal material is injected into an empty cell by the following steps A to F. Step A: A square or rectangular display area is provided by forming transparent electrode patterns on one transparent substrate and the other transparent substrate. Step B: The adhesive is applied to the filament along the periphery of the display area on one transparent substrate to provide a sealing member, and
A part of the seal member is cut out. Step C: One transparent substrate and the other transparent substrate are bonded together via a seal member, and a liquid crystal material injection hole is formed in the seal member to form an empty cell. Process D: Liquid crystal material is injected into the dish, and a voltage is applied between one electrode plate and the other electrode plate. The liquid crystal material injection hole is erected so that the side where the liquid crystal material is arranged is downward, and after the inside of the vacuum chamber is evacuated, the liquid crystal material injection hole is immersed in the liquid crystal material in the dish. Step E: An inert gas is introduced into the vacuum chamber, and the liquid crystal material is injected into the empty cell through the liquid crystal material injection hole. Step F: The liquid crystal material injection hole is sealed with an adhesive resin.