JPS59198426A - Charging method of liquid crystal - Google Patents

Abstract

PURPOSE:To prevent the wastful consumption of a liquid crystal and the pullution of an airtight tank and to prevent the defect of charging of the liquid crystal and to prevent dust from being mixed with the liquid crystal, by connecting a liquid crystal tank and a liquid crystal charging saucer so that the liquid crystal is flowed freely. CONSTITUTION:Plural liquid crystal cells 5 are held by a holder 13 in the state where charging holes of these cells 5 are turned down, and these cells 5 are set into an airtight tank 14, and the liquid crystal is put into a liquid crystal tank 11. The liquid crystal tank 11 and a liquid crystal charging saucer 12 are lowered by elevating mechanisms 21 and 29, and at first, the liquid crystal in the liquid crystal tank 11 is prevented from being flowed to the charging saucer 12. Air in an airtight tank 7 is discharged and the liquid crystal in the tank is agitated by a magnetic stirrer 20. Thereafter, the liquid crystal is flowed to a recessed part 24 of the charging saucer 12, and empty cells 5 are immersed in the liquid crystal. Next, gaseous nitrogen is charged into the tanl to seal the liquid crystal into cells. Dust is accumulated in a recessed part 26.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a liquid crystal injection method for injecting liquid crystal into a substrate for a liquid crystal display.

[Technical background of the invention and its problems]

When manufacturing a liquid crystal display, as shown in FIG. 1, a pair of glass plates (1) (1) with a plurality of segment electrodes (not shown) and a plurality of terminals connected to these formed on the surface by photoetching or the like are used. around the area with adhesive (
2) to create a space (3) for sealing the liquid crystal inside, as well as opening a part of the adhesive (2) layer to provide a liquid crystal injection port (4). A substrate (5) is formed, and liquid crystal is injected into the space (3) of the substrate (5) through an injection port (4).

Although not shown, this injection of liquid crystal is carried out on the substrate (5).

After storing the airtight tank in the airtight tank and then discharging the air in the airtight tank to create a vacuum state in the space (3), open the inlet (4).
is immersed in the liquid crystal, and then the inside of the airtight tank is returned to a higher pressure state than the vacuum state, for example, normal pressure state, and the space (3) is immersed in the liquid crystal.
The liquid crystal flows into the space (3) due to the pressure difference between the inside and outside.

In this case, since air is dissolved in the liquid crystal under normal pressure conditions, if the liquid crystal is directly injected into the substrate (5), air bubbles will form inside the liquid crystal display after it is completed, resulting in problems such as incomplete display. Therefore, the liquid crystal is placed in a vacuum environment in advance to remove the dissolved gas in the liquid crystal, and then the liquid crystal is transferred to a liquid crystal injection dish with an open top and stored in an airtight tank.
Furthermore, when creating a vacuum inside the airtight tank, the liquid crystal injection dish was vibrated to remove dissolved gas within the liquid crystal.

This is because even if the dissolved gas in the liquid crystal is completely removed in advance, the air will melt again as the liquid crystal comes into contact with air until the liquid crystal is transferred to the liquid crystal filling dish and the airtight tank is evacuated. The purpose of applying vibration to the liquid crystal injection tray is to remove dissolved gases that have become bubbles within the liquid crystal.

At this time, the bubbles in the liquid crystal burst at the liquid surface, but since the top of the liquid crystal pouring pan is open and vibration is applied to the liquid crystal pouring pan, liquid crystal droplets are not scattered into the airtight tank. This will waste expensive liquid crystals and contaminate the inside of the airtight tank.Furthermore, at this time, the liquid crystal display substrate (5) is located directly above the liquid crystal pouring pan, Since the liquid crystal injection port (4) is on standby with facing the liquid crystal surface, droplets of liquid crystal may block the injection port, which may cause problems in subsequent injection of liquid crystal.

In addition, in this case, each time the liquid crystal is injected, the liquid crystal is manually transferred to the liquid crystal injection tray, so it is easy for dust to get into the liquid crystal. The number of substrates (5) that can be processed is limited, and if the substrates (5) are large, the processing capacity is significantly reduced.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned points, and prevents wasteful consumption of liquid crystal and contamination of an airtight tank, prevents improper injection of liquid crystal, further prevents contamination of dust, and furthermore, , the aim is to significantly improve processing power.

[Summary of the invention]

In the liquid crystal injection method of the present invention, a liquid crystal tank and a liquid crystal injection dish are connected so that the liquid crystal can flow freely, and the liquid crystal is moved into the liquid crystal tank by lowering the liquid crystal tank or raising the liquid crystal injection plate. The area around the liquid crystal injection pan and the liquid crystal display substrate is vacuumed to create a vacuum inside the liquid crystal display substrate and the dissolved gas inside the liquid crystal is removed. By lowering, the liquid crystal in the liquid crystal tank is moved to the liquid crystal injection dish to maintain a predetermined liquid level, and the liquid crystal injection port of the liquid crystal display substrate is immersed in the liquid crystal moved to the liquid crystal injection dish by an appropriate method.
Next, the liquid crystal tank, the liquid crystal injection dish, and the liquid crystal display substrate are brought into a higher pressure state than the vacuum state, and the liquid crystal in the liquid crystal injection dish is injected into the inside of the liquid crystal display substrate. The gas dissolved in the liquid crystal is removed in the liquid crystal tank, and the liquid crystal is transferred directly to the liquid crystal injection pan. After the liquid crystal injection is completed, the liquid crystal is collected from the liquid crystal injection pan into the liquid crystal tank.

[Embodiments of the invention]

The liquid crystal injection method of the present invention will be specifically explained based on embodiments shown in the drawings.

In Figures 2 to 4, αυ is a liquid crystal tank, 1 is a liquid crystal pouring pan, and 1 is a liquid crystal display substrate (shown in Figure 1).
The holder for holding multiple plates of 5), rJ4), is an airtight tank.

The liquid crystal tank (11) has a capacity sufficient to inject liquid crystal several times or more, has an openable/closeable lid at the top, and has a plurality of connection ports formed at the side near the bottom. At the same time, two liquid level sensors α for detecting the liquid level in the tank (11) are connected, and a magnetic stirrer for promoting removal of dissolved gas is provided below the sensor.

This liquid crystal tank (till) is provided in the airtight tank (14) and is raised and lowered by a lifting mechanism Q1.

It should be noted that when the liquid crystal tank αD is lowered, its bottom part is bent so as to face the magnetic stirrer (2).

In addition, the liquid crystal pouring dish (L';!J) has a recess (C) on its upper surface for storing the liquid crystal, and the depth gradually increases toward one side at the bottom of the recess (C). It has an inclined groove (c), and a concave part (c) for collecting dust and a concave part (5) for collecting liquid crystal are provided at the negative side bottom of this groove (c). A connection port (A) is opened from the bottom to one side of the injection plate α2.

And, this liquid crystal injection plate←2 is connected to the airtight tank (14
A flexible connecting vibrator (to) which is provided in the interior and is raised and lowered by a lifting mechanism (a), and whose connection port (c) is connected to one of the connection ports α of the liquid crystal tank Q4). connected via.

Note that a liquid level sensor 01 for detecting the liquid level of the liquid crystal in the recess is provided at the top of this liquid crystal injection tray (Iz).

Further, the holder a3 is detachably provided above the liquid crystal injection plate α2 in the airtight tank a4.

Next, the effect will be explained.

First, place multiple liquid crystal display substrates (5) in holder α3,
Hold the liquid crystal inlet (4) facing downward,
It is installed in a predetermined position in the airtight tank α4, and the liquid crystal is placed in the liquid crystal tank αD.

At this time, do not use the liquid crystal tank (11).
81 is closed with a cap 04), and the liquid crystal tank αυ and liquid crystal pouring plate α2 are closed by each lifting mechanism 0 (a).
In particular, the liquid crystal tank circle is sufficiently lowered from the liquid crystal injection pan α2, and placed in the liquid crystal tank aD.

Next, seal the airtight tank <141 so that the liquid crystal placed in it does not flow into the pouring pan tta, and operate the start switch.The air in the airtight tank (L4) is exhausted using a vacuum pump, etc., and the magnetic The stirrer is activated to stir the liquid crystal in the liquid crystal tank I.

As a result, the inside of the airtight tank α4) gradually becomes a vacuum state, the space (3) inside the substrate (5) gradually becomes a vacuum state, and the dissolved gas in the liquid crystal in the liquid crystal tank (1]) also becomes a vacuum state. It becomes bubbles and is removed from the liquid crystal surface.

Note that at this time, the bubbles generated within the liquid crystal burst on the liquid surface, but since the liquid crystal tank (11) has a lid (17), liquid crystal droplets are scattered to the outside of the liquid crystal tank (11). There is no need to waste liquid crystal, or use an airtight tank 14
There is no possibility of contaminating the interior or blocking the liquid crystal injection port (4) of the substrate (5). Further, some of the bubbles generated within the liquid crystal adhere to the inner wall of the liquid crystal tank circle, but these are separated from the inner wall and removed from the liquid surface by the action of the magnetic stirrer (a).

Then, after 1 to several hours have passed, the airtight tank (1
4) and the space (3) of the substrate (5) have a predetermined degree of vacuum, and the dissolved gas in the liquid crystal is also completely removed.

In this state, the vacuum pump and magnetic stirrer (20) stop, the liquid crystal tank (11) is raised by the lifting mechanism C2), and the liquid crystal inside opens to the connection port (L8. When the liquid crystal liquid level in the recess reaches the set value, the liquid level sensor 0η detects this, and this detection signal activates the lifting mechanism. 121) by liquid crystal tank (
lυ stops rising.

Next, each lifting mechanism 021) +21 raises the liquid crystal tank and the liquid crystal injection tray O4 by a predetermined distance in synchronization, thereby opening the liquid crystal injection port of each liquid crystal display substrate (5) held in the holder (one position). (4) is immersed in the liquid crystal in the liquid crystal injection dish fIZ.

Then, the entire gas is gradually injected into the airtight tank aa, and the pressure inside the airtight tongue is gradually increased to a normal pressure state.

Due to this, the space (
3) A pressure difference occurs within the injection tray Oz.
The liquid crystal inside the space (
3) Flow into the interior.

It takes one to several hours for this liquid crystal to completely flow in, but when the liquid crystal in the liquid crystal pouring tray (1, 21) decreases and the liquid level drops, the liquid level sensor 01 detects this and sends a detection signal. As a result, the lifting mechanism C21) is activated, the liquid crystal tank (111) is raised, and the liquid crystal filling plate (111) is moved from the liquid crystal tank aυ.
When the liquid crystal is supplied to 2 and the liquid level returns to the set value, the liquid crystal tank (Ll) is raised and lowered again by the liquid level sensor (311), and the liquid crystal tank (Ll) stops rising by υ, and the liquid crystal filling tray 02
The liquid crystal level of the liquid crystal is maintained at a predetermined set value, thereby allowing liquid crystal to be injected into a large number of substrates (5) regardless of their size.

Next, the liquid crystal tank α is lowered by the lifting mechanism (21), and the liquid crystal in the liquid crystal injection plate (12) flows into the liquid crystal tank αυ and collected, and then the liquid crystal injection plate is lowered by the lifting mechanism 2!ll. The board (5) held by the holder (131)
) to move away from

Incidentally, when the liquid crystal is collected, dust such as minute glass pieces adhering to the substrate (5) is collected in the recess (c).

Finally, the airtight tank I is opened and the substrates (5) are taken out for each holder αJ to complete the injection.

Note that all operations from sealing the airtight tank I and operating the start switch to opening the airtight tank a4 can be performed automatically.

In addition, if you put liquid crystal for several times in the liquid crystal tank Qll, you can continue pouring liquid crystal by simply holding the next board (5) in the holder and mounting it in the specified position in the airtight tank I. can be done.

In addition, since the liquid crystal tank I has multiple connection ports (IF!i), it is possible to supply liquid crystal to multiple liquid crystal injection groups. Different types of liquid crystal can be injected at the same time, and the type of liquid crystal can be easily switched.

Next, another embodiment will be described.

The apparatus shown in FIG. 5 differs from the above-described apparatus in that it does not require a lifting mechanism (two) on the liquid crystal injection tray (12), but instead has a holder (one).
3) is equipped with an elevating mechanism 07), which is used for liquid crystal injection pans.
When immersing the injection port (4) of the substrate (5) into the liquid crystal inside the
The only difference is that the holder αJ is lowered by a lifting mechanism (b), and other points are substantially the same.

Although it is not shown, the liquid crystal tank A1J has a lifting mechanism (
21J is not provided, the liquid crystal injection plate Q'IJ and the holder [
13 may be provided with an elevating mechanism (291 (37). In this case, the liquid crystal is supplied and collected from the liquid crystal tank αυ to the liquid crystal injection plate←2 by lowering and raising the liquid crystal injection plate (13), and the substrate (291 (37) for the liquid crystal is 5) Dip the holder 0
The liquid crystal injection method and the holder 13 are formed to descend in synchronism when the liquid crystal level in the liquid crystal injection pan α2 is lowered by injection.

In the above embodiment, the magnetic stirrer 4 was used to promote the removal of gas dissolved in the liquid crystal in the liquid crystal tank <11), but the present invention is not limited to this. May be used.

〔Effect of the invention〕

As described above, according to the present invention, the dissolved gas of the liquid crystal is completely removed within the liquid crystal tank, so that the expensive liquid crystal is not wasted and the inside of the airtight tank is not contaminated. Moreover, since the liquid crystal from which dissolved gases have been removed is transferred to the liquid crystal injection tray without being exposed to the atmosphere, the liquid crystal injection port of the liquid crystal display substrate will not be blocked by liquid crystal droplets, and defective products will be eliminated. Occurrence can be prevented. Furthermore, since the liquid crystal can be supplied from the liquid crystal tank to the liquid crystal injection pan every 9 times, it can be collected in the crystal tank, so there is no need for manual handling and contamination of dust can be prevented. Since the surface can be maintained, a large number of substrates can be processed regardless of the size of the substrate, and processing capacity can be greatly improved.

[Brief explanation of drawings]

Figure 1 is a partially cutaway perspective view of a liquid crystal display board;
2 to 4 show an embodiment of a device to which the liquid crystal injection method of the present invention is applied, FIG. 2 is a perspective view thereof, FIG. 3 is a front view thereof, and FIG. 4 (α) (the phrase is Each is a cross-sectional view of the liquid crystal injection tray, and the fifth @ is a front view showing another embodiment. (3)--Space inside the liquid crystal display substrate (5), (4)
) @・Liquid crystal injection port, (5)・・LCD display board, C
1, l)...Liquid crystal tank, 0z...Liquid crystal injection dish. April 26, 1980 Inventor Hisashi Ishiwatari Akito Yoko Sasaki 1) Rodo Yoshi
Fumio Takeuchi Patent applicant Tokyo Shibaura Electric Co., Ltd. Figure 3, No. 4 Figure 4

Claims (1)

[Claims] (1) Connect the liquid crystal tank and liquid crystal filling dish so that the liquid crystal can flow freely, and connect the liquid crystal tank, liquid crystal filling plate, and liquid crystal display with the liquid crystal moving to the liquid crystal tank by lowering the liquid crystal tank or raising the liquid crystal filling dish. The surroundings of the liquid crystal display substrate are vacuumed to create a vacuum inside the liquid crystal display substrate and the dissolved gas in the liquid crystal is removed.Then, the liquid crystal in the liquid crystal tank is injected by raising the liquid crystal tank or lowering the liquid crystal injection pan. At the same time, the liquid crystal injection port of the liquid crystal display substrate is immersed in the liquid crystal transferred to the liquid crystal injection dish, and then the surroundings of the liquid crystal tank, liquid crystal injection plate, and liquid crystal display substrate are placed in a higher pressure than the vacuum state described above. A liquid crystal injection method characterized by injecting liquid crystal from a liquid crystal injection tray into the inside of a liquid crystal display substrate.