JPH10253974A - Liquid crystal filling method and liquid crystal filling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal filling method and a liquid crystal filling device capable of filling liquid crystal in a short time efficiently without contaminating liquid crystal. SOLUTION: An evacuating nozzle 28 is connected to the discharge port of a liquid crystal cell 11 and also the injection port of the liquid crystal 11 is immersed in the liquid crystal 42 stored in a liquid crystal reservoir 34. Then, the liquid crystal is injected into the inside of the liquid crystal cell 11 from the injection port with the pressure difference between the inside and the outside of the liquid crystal cell by evacuating the inside of the liquid crystal cell from the discharge port while pressurizing the inside of a containing chamber 20, in which the liquid crystal cell is arranged.

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 method for injecting liquid crystal into a gap between two substrates of a liquid crystal cell, and a liquid crystal injection device.

[0002]

2. Description of the Related Art A liquid crystal cell serving as a display device has an array substrate and a counter substrate, and these two substrates are adhered to each other via a sealing material and face each other with a predetermined gap. A liquid crystal is sealed between these two substrates.

In general, as a liquid crystal injection device for injecting liquid crystal between two substrates of a liquid crystal cell, a device having a vacuum chamber and a liquid crystal reservoir disposed in the vacuum chamber is known. When performing liquid crystal injection using such a liquid crystal injection device, a liquid crystal cell having one or a plurality of injection ports formed in a sealing material is placed in a vacuum chamber, and then the inside of the vacuum chamber is evacuated. The inside is evacuated to a vacuum. Then, after the inlet of the liquid crystal cell is immersed in the liquid crystal in the liquid crystal reservoir while maintaining the vacuum state, the inside of the vacuum chamber is returned to the atmospheric pressure. Thereby, the liquid crystal in the liquid crystal reservoir is filled in the liquid crystal cell due to the pressure difference between the inside and outside of the liquid crystal cell. After injecting the liquid crystal, the liquid crystal cell is taken out of the vacuum chamber, and the injection port is sealed with an ultraviolet curing agent or the like.

Further, as a liquid crystal injection apparatus not using a vacuum chamber, there is known a liquid crystal injection apparatus in which an injection nozzle and an exhaust nozzle are directly attached to a liquid crystal cell, and the liquid crystal is injected while the inside of the liquid crystal cell is exhausted. That is, according to this type of injection device, the injection nozzle is connected to the liquid crystal storage tank, and the exhaust nozzle is connected to the vacuum suction system. These nozzles are directly connected to an injection port and an exhaust port provided in a sealing material of the liquid crystal cell, and inject liquid crystal from the injection port while exhausting the inside of the liquid crystal cell from the exhaust port. After the liquid crystal reaches the outlet, the inlet and the outlet are sealed with an ultraviolet curing agent or the like. According to such an injection apparatus, the liquid crystal injection time can be shortened as compared with the method using a vacuum chamber.

[0005]

In a liquid crystal injection device using a vacuum chamber as described above, it is necessary to evacuate the entire vacuum chamber in which the liquid crystal cell is disposed, so that the degree of vacuum required for liquid crystal injection is reduced. It takes a long time to exhaust. When the evacuation time and the injection time are summed, for example, in the case of a liquid crystal cell of an 11-inch size, about 10 hours are required. It is very undesirable that one manufacturing process requires as much as 10 hours in terms of productivity and the like.

[0006] Further, after the inside of the liquid crystal cell is evacuated, the liquid crystal is injected into a sealed space between the substrates. Therefore, when the residual gas inside the liquid crystal cell has not been sufficiently removed, or when the gas is discharged into the liquid crystal. In the case of dissolution, there is no place for escape of these residual gases and gases, and there is a possibility that bubbles may remain at a position diagonally opposite to the injection port in the liquid crystal cell. In particular, when the gap between the substrates is as small as about 3 μm, it is difficult to completely exhaust the inside of the gap, and bubbles are likely to remain.

On the other hand, in a liquid crystal injection device using an injection nozzle and an exhaust nozzle, since the injection nozzle is directly attached to each liquid crystal cell and the liquid crystal is injected under pressure, no liquid crystal leak occurs at the injection port. In order to achieve this, high precision is required for the shape of the injection nozzle and the shape of the injection port of the liquid crystal cell. However, when performing mass production, it is very difficult to produce a liquid crystal cell with such accuracy. In addition, it is necessary to provide the injection nozzle and the exhaust nozzle only for the number of liquid crystal cells to be set, and the manufacturing equipment becomes expensive. Furthermore, since the nozzle is in direct contact with the injection port of the liquid crystal cell, display defects due to contamination of the liquid crystal cell (white spots, etc.)
Tends to occur and there is a problem.

The present invention has been made in view of the above points, and an object of the present invention is to provide a liquid crystal injection method and a liquid crystal injection device capable of injecting liquid crystal efficiently in a short time without causing contamination of a liquid crystal cell. It is in.

[0009]

In order to achieve the above-mentioned object, a liquid crystal injection method according to the present invention comprises two substrates bonded to each other with a predetermined gap therebetween by a sealing material, and a liquid crystal injection method formed on the sealing material. In a liquid crystal injection method of injecting liquid crystal into a liquid crystal cell having an inlet and an exhaust port, the liquid crystal cell is evacuated from the exhaust port while the injection port of the liquid crystal cell is immersed in the liquid crystal. The liquid crystal is injected into the liquid crystal cell from the injection port by a pressure difference between the inside and the outside.

Further, according to the liquid crystal injection method of the present invention, the inside of the liquid crystal cell is evacuated while applying atmospheric pressure to the outside of the liquid crystal cell or applying a pressure higher than the atmospheric pressure. It is characterized by:

According to a fifth aspect of the present invention, there is provided a liquid crystal injection apparatus comprising: two substrates bonded to each other with a predetermined gap by a sealing material; and an injection port and an exhaust port formed in the sealing material. In a liquid crystal injection device for injecting liquid crystal into a cell, a liquid crystal reservoir in which liquid crystal is stored in contact with an injection port of the liquid crystal cell and an exhaust port of the liquid crystal cell are connected, and the inside of the liquid crystal cell is exhausted through the exhaust port. Exhaust means for injecting the liquid crystal through the injection port by a pressure difference between the inside and outside of the liquid crystal cell.

According to a sixth aspect of the present invention, there is provided a liquid crystal injection apparatus comprising: two substrates bonded to each other with a predetermined gap by a sealing material; and an injection port and an exhaust port formed in the sealing material. In a liquid crystal injection device for injecting liquid crystal into a cell, a pressure vessel having an enclosed space for accommodating the liquid crystal cell therein, and a liquid crystal disposed in the pressure vessel and in contact with an injection port of the liquid crystal cell. And a pressurizing means for pressurizing the inside of the pressure vessel, and connected to an exhaust port of the liquid crystal cell, the inside of the liquid crystal cell is exhausted through the exhaust port, and the injection port is formed by a pressure difference between the inside and outside of the liquid crystal cell. And an exhaust means for injecting the liquid crystal therethrough.

According to the liquid crystal injection method and the liquid crystal injection device configured as described above, the liquid crystal is injected through the injection port while exhausting the inside of the liquid crystal cell directly from the exhaust port provided in the liquid crystal cell. At this time, in order to prevent the nozzle from directly contacting the injection port of the liquid crystal cell, an atmospheric pressure or a pressure higher than the atmospheric pressure is applied to the outside of the liquid crystal cell while the injection port is immersed in the liquid crystal.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, as shown in FIG. 1, a liquid crystal cell 11 into which liquid crystal is injected by the liquid crystal injection device according to the present embodiment has a rectangular array substrate 10 and a counter substrate 12, and these two substrates are sealed. The peripheral parts are pasted together via the material 14,
They are arranged facing each other with a predetermined gap. In addition, an injection port 16 for injecting the liquid crystal and an exhaust port 18 for exhausting the air in the liquid crystal cell are formed in the sealing material 14, and are opposite to each other in the diagonal direction of the array substrate 10 and the counter substrate 12. Located at one corner.

On the other hand, as shown in FIG. 2, the liquid crystal injection device includes a pressure vessel 22 having a housing chamber 20 as an enclosed space therein, and the housing chamber 20 is connected to a pressure pump 26 via a pressure pipe 24. It is connected to the. Also,
An exhaust nozzle 28 is provided in the storage chamber 20, and is connected to the pressure vessel 22 through an exhaust pipe 30.
It is connected to an external vacuum pump 32. Pressurizing pump 2
6 and the pressurizing pipe 24 function as pressurizing means in the present invention, and the exhaust nozzle 28, the exhaust pipe 30, and the vacuum pump 32 function as exhaust means in the present invention.

In the housing chamber 20, a liquid crystal reservoir 34 is provided. The liquid crystal reservoir 34 includes a storage block 38 fixed to the upper end of a vertically extending support post 36.
And an injection boat 40 on the horizontal upper surface of the storage block.
Are formed. The injection boat 40 is formed of a recess having a right-angled triangular cross-sectional shape, and stores the defoamed liquid crystal 42.

When injecting a liquid crystal between the substrates of the liquid crystal cell 11 using the liquid crystal injection device configured as described above, first, the liquid crystal cell 11 is set in the accommodation chamber 20 of the pressure vessel 22. In this case, the inlet 16 of the liquid crystal cell 11 is set in the vertical direction with the exhaust port facing down and the corners of the liquid crystal cell 11 are set so that the entire inlet 16 is immersed in the liquid crystal 42. It is set on the injection board 40 of the reservoir 34. An exhaust nozzle 28 is attached to the exhaust port 18 of the liquid crystal cell 11.

In this state, by closing the pressure vessel 22 and operating the vacuum pump 32, the inside of the liquid crystal cell 11 is evacuated through the exhaust nozzle 28 at, for example, about 0.5 torr. As a result, a pressure difference is generated between the inside and the outside of the liquid crystal cell 11, and the liquid crystal 42 is injected into the liquid crystal cell 11 from the liquid crystal reservoir 34 through the injection port 16. At this time, in order to increase the injection speed of the liquid crystal 42, the pressure pump 26 is operated to pressurize the inside of the storage chamber 20, that is, pressurize the outside of the liquid crystal cell 11 to increase the pressure difference between the inside and outside of the liquid crystal cell 11.

By continuing to exhaust the liquid crystal cell 11 and pressurize the storage chamber 20, the residual gas in the liquid crystal cell and the gas dissolved in the liquid crystal are exhausted, and the liquid crystal 42 is entirely formed in the liquid crystal cell. Injected.

According to the liquid crystal injection device and the liquid crystal injection method configured as described above, only the minute space in the liquid crystal cell 11 needs to be evacuated, and the entire chamber containing the liquid crystal cell is evacuated as in the conventional case. Since there is no need to exhaust,
The time required for exhaust can be significantly reduced. For example, when injecting liquid crystal into a liquid crystal cell having an 11-inch size, the liquid crystal injection time can be reduced from about 10 hours in the past to 2-3 hours. Therefore, it is possible to greatly increase the production efficiency of the liquid crystal cell. At the same time, the inside of the liquid crystal cell 11 can be easily and reliably evacuated, and the liquid crystal can be injected without generating bubbles due to residual gas in the liquid crystal cell and gas dissolved in the liquid crystal.

Further, since the injection method is such that the injection nozzle is not immersed in the injection port of the liquid crystal cell 11 but is immersed in the liquid crystal 42 in the liquid crystal reservoir 34, the shape of the injection port and the injection nozzle can be adjusted with accuracy. It is possible to cope with it without making it well, and it is easy to reduce the manufacturing cost and to cope with mass production. At the same time, contamination of the liquid crystal cell near the injection port can be prevented.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, in the above-described embodiment, a case has been described in which the present invention is applied to a liquid crystal cell having an inlet and an outlet at two corners along a diagonal direction. However, the present invention is not limited to this, and as shown in FIG. The present invention is also applicable to a liquid crystal cell having an inlet 16 and an outlet 18 at two opposing sides.

In this case, as shown in FIG. 4, in the liquid crystal reservoir 34 of the liquid crystal injection device, the injection boat 40 formed on the horizontal upper surface of the storage block 38 is constituted by a shallow flat recess, and the liquid crystal 42 It is stored in a raised state due to surface tension. The other configuration of the liquid crystal injection device uses the same configuration as the above-described embodiment. Then, the liquid crystal cell is set so that the injection port 16 is in contact with and immersed in the liquid crystal 42, and the liquid crystal is injected by the same method as described above.

According to such a configuration, the same operation and effect as those of the above-described embodiment can be obtained, and the amount of the liquid crystal 42 filled in the liquid crystal reservoir 34 can be reduced to a necessary minimum. Can be used without waste to improve material efficiency.

In the above embodiment, the liquid crystal is injected while pressurizing the outside of the liquid crystal cell. However, the present invention is not limited to this. The liquid crystal may be injected by the above method.
In this case, there is no need to provide the pressure container 22 and the pressure pump 26, and the liquid crystal injection device can be simplified. Note that the number of inlets and outlets formed in the liquid crystal cell can be increased as necessary.

[0026]

As described above in detail, according to the present invention, the liquid crystal is directly injected into the liquid crystal cell through the injection port while exhausting only the inside of the liquid crystal cell. It is possible to provide a liquid crystal injection method and a liquid crystal injection apparatus capable of injecting liquid crystal efficiently by substantially shortening the liquid crystal injection time as compared with the related art without causing generation of the liquid crystal.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a structure of a liquid crystal cell.

FIG. 2 is a sectional view schematically showing a liquid crystal injection device according to the embodiment of the present invention.

FIG. 3 is a perspective view showing the structure of another liquid crystal cell.

FIG. 4 is a cross-sectional view schematically showing a liquid crystal injection device according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Array substrate 11 ... Liquid crystal cell 12 ... Counter substrate 14 ... Sealing material 16 ... Injection port 18 ... Exhaust port 20 ... Housing chamber 22 ... Pressure vessel 26 ... Pressurizing pump 28 ... Exhaust nozzle 32 ... Vacuum pump 34 ... Liquid crystal reservoir 40 ... Injection boat 42 ... Liquid crystal

Claims (6)

[Claims] 1. A liquid crystal injection method for injecting liquid crystal into a liquid crystal cell having two substrates bonded to each other with a predetermined gap by a sealing material, and an injection port and an exhaust port formed in the sealing material. In the state where the injection port of the liquid crystal cell is immersed in liquid crystal, the inside of the liquid crystal cell is evacuated from the exhaust port, and the liquid crystal is injected into the liquid crystal cell from the injection port by a pressure difference between the inside and outside of the liquid crystal cell. Characteristic liquid crystal injection method. 2. The liquid crystal injection method according to claim 1, wherein the inside of the liquid crystal cell is evacuated while atmospheric pressure is applied to the outside of the liquid crystal cell. 3. The liquid crystal injection method according to claim 1, wherein the inside of the liquid crystal cell is evacuated while a pressure higher than the atmospheric pressure is applied to the outside of the liquid crystal cell. 4. The liquid crystal injection method according to claim 3, wherein the liquid crystal cell is disposed in a closed space, and the exhaust is performed while pressurizing the closed space. 5. A liquid crystal injection device for injecting a liquid crystal into a liquid crystal cell having two substrates bonded together with a predetermined gap by a sealing material and an injection port and an exhaust port formed in the sealing material. A liquid crystal reservoir in which liquid crystal is stored in contact with an injection port of the liquid crystal cell; and a liquid crystal cell connected to an exhaust port of the liquid crystal cell. An evacuation unit for injecting the liquid crystal through an inlet; 6. A liquid crystal injection device for injecting liquid crystal into a liquid crystal cell having two substrates bonded together with a predetermined gap by a sealing material and an injection port and an exhaust port formed in the sealing material. A pressure vessel having an enclosed space for accommodating the liquid crystal cell therein; a liquid crystal reservoir disposed in the pressure vessel and storing liquid crystal in contact with an injection port of the liquid crystal cell; Pressurizing means for pressurizing, and exhaust means connected to an exhaust port of the liquid crystal cell, exhausting the inside of the liquid crystal cell through the exhaust port, and injecting the liquid crystal through the injection port by a pressure difference between the inside and outside of the liquid crystal cell. A liquid crystal injection device, comprising: