JPH03200211A - Method for supplying liquid crystal to substrate for liquid crystal element - Google Patents

Abstract

PURPOSE:To allow the supply of always the specified amt. of a liquid crystal with simple control by immersing perpendicular bar-shaped liquid crystal pulling-up pins into a liquid crystal bath, then pulling up these pins and bringing the front ends thereof into contact with the front surface of the liquid crystal sealing region of a substrate, thereby transferring and supplying the liquid crystal which is stuck to the liquid crystal pulling-up pins and is pulled up from the liquid crystal bath on the substrate. CONSTITUTION:The liquid crystal of the liquid crystal bath A is stuck to the liquid crystal pulling-up pins 21 and the pins are pulled up from the liquid crystal bath A. The tip ends of the liquid crystal pulling-up pins 21 are brought into contact with the front surface of the substrate 11, by which the liquid crystal sticking to the liquid crystal pulling-up pins 21 is transferred and supplied onto the substrate 11. The amt. of the liquid crystal transferred from the liquid crystal pulling-up pins 21 onto the substrate 11 is, therefore, determined mainly by the diameter of the liquid crystal pulling-up pins 21, the pulling up speed of the liquid crystal pulling-up pins 21 from the liquid crystal bath and the time before the liquid crystal pulling-up pins 21 are pulled up from the liquid crystal bath A and are brought into contact with the front surface of the substrate 21; therefore, the amt. of the liquid crystal supplied onto the substrate 11 is kept constant if the pulling speed and the time before the liquid crystal pulling-up pins 21 are brought into contact with the front surface of the substrate 11 are set at specified values. The always specified amt. of the liquid crystal is supplied onto the substrate by the simple control.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of supplying liquid crystal to a substrate for a liquid crystal element.After assembling a liquid crystal element by polymerizing and bonding the substrates through a frame-shaped sealing material, The liquid crystal was manufactured by injecting liquid crystal using a vacuum injection method through a liquid crystal injection port provided in a part of the sealing material, but recently, before assembling the liquid crystal element, one of the pair of substrates making up the liquid crystal element is A manufacturing method in which a liquid crystal is supplied onto one substrate and then the pair of substrates are polymerized and bonded to assemble a liquid crystal element has been adopted.

In this way, when liquid crystal is supplied onto one of the substrates before the liquid crystal element is assembled, the liquid crystal is conventionally supplied by a method as shown in FIG.

In FIG. 7, reference numeral 1 is a transparent substrate for a liquid crystal element made of a glass plate, etc., and on one side of this substrate are transparent electrodes for display made of ITO etc. and an alignment treatment film (none of which are shown). is formed, and a frame-shaped sealing material 2 made of a thermosetting adhesive is also formed. After the liquid crystal is supplied to the liquid crystal filling area surrounded by the frame-shaped sealing material 2, this substrate 1 is connected to another substrate (not shown) that forms a pair with this substrate 1 and the frame-shaped sealing material 2. It is polymerized and bonded through.

On the other hand, in FIG. 7, reference numeral 3 denotes an air extrusion type dispenser for supplying liquid crystal to the liquid crystal sealed area of the substrate. This dispenser 3 consists of a cylindrical tank part 3a that accommodates the liquid crystal a, a nozzle part 3b provided vertically at the lower end of this tank part 3a, and an air hose 4 at the upper end of the tank part 3a. is connected.

In order to supply the liquid crystal to the liquid crystal sealed area of the substrate 1, the substrate 1 is carried under the dispenser 3, and approximately the center of the liquid crystal sealed area is opposed to the nozzle part 3b of the dispenser 3.
In this state, air is supplied from the air hose 4 to the tank portion 3a of the dispenser 3, and the liquid crystal a in the tank portion a is dripped onto the substrate l from the nozzle portion 3b using this air pressure.

[Problem to be solved by the invention]

However, in the conventional liquid crystal supply method described above, the liquid crystal a in the dispenser 3 is extruded by air pressure and dripped onto the substrate 1. Therefore, in order to supply a certain amount of liquid crystal a onto the substrate 1, the air pressure is In addition, it is necessary to strictly control the air supply time, so controlling the liquid crystal supply amount is troublesome, and the remaining amount of liquid crystal in the dispenser 3 decreases as the liquid crystal a is repeatedly supplied to the substrate 1. Therefore, even if the air pressure and air supply time are controlled constant, the liquid crystal a on the substrate 1 may change due to changes in the amount of liquid crystal remaining in the dispenser 3.
The problem was that the supply amount fluctuated.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a liquid crystal display for a liquid crystal element substrate that can always supply a constant amount of liquid crystal onto the substrate with simple control. The goal is to provide a supply method.

[Means to solve the problem]

The method of supplying liquid crystal to a substrate for a liquid crystal element of the present invention is to immerse a vertical rod-shaped liquid crystal pulling pin in a liquid crystal volume, then pull the liquid crystal pulling pin up from the liquid crystal volume, and place the tip of the pin on the upper surface of the liquid crystal enclosure area of the substrate. The present invention is characterized in that the liquid crystal that has been brought into contact with the liquid crystal lifting pin and has been lifted from the liquid crystal amount is transferred and supplied onto the substrate.

[Effect]

That is, the method of supplying liquid crystal to a substrate for a liquid crystal element according to the present invention involves attaching an amount of liquid crystal to a liquid crystal pulling pin and pulling it up from the liquid crystal amount, and then transferring the liquid crystal attached to the liquid crystal pulling pin to the substrate with the tip of the liquid crystal lifting pin. The amount of liquid crystal transferred from the liquid crystal pulling pin to the substrate is mainly determined by the diameter of the liquid crystal pulling pin and the amount of liquid crystal pulling pin. This is determined by the pulling speed and the time it takes for the liquid crystal pulling pin to be pulled up from the amount of liquid crystal until it comes into contact with the top surface of the substrate, so the pulling speed of the liquid crystal pulling pin and the time it takes for the liquid crystal pulling pin to come into contact with the top surface of the substrate can be controlled to a constant value. Then, the amount of liquid crystal supplied onto the substrate becomes constant. Therefore, according to this liquid crystal supply method, a constant amount of liquid crystal can always be supplied onto the substrate with simple control.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

1 and 2 show the liquid crystal supply method of this embodiment. In the figures, 11 is a transparent substrate for a liquid crystal element made of a glass plate, etc., and this substrate 11 is as shown in FIG. 4. To,
The area is equivalent to a plurality of liquid crystal elements (four in this embodiment). A transparent electrode for display made of ITO or the like and an alignment treatment film (none of which are shown) are formed on each liquid crystal element portion on the surface of the substrate 11, and a liquid crystal filling area surrounding each liquid crystal element portion is formed. A frame-shaped sealing material 12 made of a thermosetting adhesive is formed.

On the other hand, in FIGS. 1 and 2, 20 is the substrate 1.
This is a liquid crystal tray that accommodates liquid crystal a to be supplied to each liquid crystal sealed area of 1, and the amount A of liquid crystal in this liquid crystal tray 20 is kept at a substantially constant temperature by a temperature adjustment mechanism (not shown). The bath surface is kept almost constant by a liquid crystal replenishment mechanism (not shown). Also, 2
Reference numeral 1 denotes a liquid crystal pulling pin that pulls up the liquid crystal a from the liquid crystal amount A in the liquid crystal tray 20 and supplies it to the liquid crystal sealed area of the substrate 11. This liquid crystal pulling pin 21 is made of a round bar made of metal or synthetic resin with a smooth surface, and is a pin holder 22 that is moved up and down and laterally by a moving mechanism (not shown).
is fixed vertically. In this embodiment, two liquid crystal pulling pins 21 of the same standard are provided on the pin holder 22 at an interval smaller than the width of the liquid crystal filling area.

The liquid crystal supply method of this embodiment is based on the above-mentioned liquid crystal pulling pin 21.
, the liquid crystal a is transferred from the liquid crystal reservoir A to the liquid crystal sealed area of the substrate 11.
This liquid crystal supply is carried out as follows; First, as shown in FIG. Then, the two liquid crystal pulling pins 21 are immersed for a predetermined length into the liquid crystal reservoir A in the liquid crystal tray 20, and the liquid crystal a in the liquid crystal bath A is attached to the liquid crystal pulling pins 21. next,
The pin holder 22 is raised to pull up the liquid crystal pulling pin 21 from the liquid crystal reservoir A. At this time, the liquid crystal a attached to the liquid crystal pulling pin 21 and pulled up from the liquid crystal reservoir A flows down the liquid crystal pulling pin 21 to the tip (lower end) side as the liquid crystal pulling pin 21 is pulled up, and finally the liquid crystal a is pulled up from the liquid crystal reservoir A. Only the amount that adheres to the tip of the pulling pin 21 in a spherical shape due to surface tension is pulled up. The amount of liquid crystal a attached to the tip of liquid crystal pulling pin 21 and pulled up is mainly determined by the viscosity and surface tension of liquid crystal a, the diameter of liquid crystal pulling pin 21, and the amount of liquid crystal pulling pin 21 pulled up from liquid crystal reservoir A. Depends on speed. Next, the liquid crystal pulling pin 21 pulled up from the liquid crystal reservoir A is temporarily stopped on the liquid crystal bath A, and after that, the pin holder 22 is moved laterally and the liquid crystal pulling pin 21 is carried into the liquid crystal supply position on one of the substrates 11. The pin holder 22 is moved above the liquid crystal sealed area of the liquid crystal element portion, and the pin holder 22 is then lowered to bring the tips of the two liquid crystal pulling pins 21 into contact with the upper surface of the liquid crystal filled area of the substrate 11 at the same time. Here, the reason why the liquid crystal pulling pin 21 pulled up from the liquid crystal reservoir A is temporarily stopped on the liquid crystal bath A is to further adjust the amount of liquid crystal attached to the liquid crystal pulling pin 21, and the excess liquid crystal a is stopped above the liquid crystal bath A. Since the liquid crystal is dripped into the liquid crystal reservoir A during this time, the amount of liquid crystal adhered to the liquid crystal pulling pin 21 will eventually become the amount that is maintained by surface tension. The final amount of the liquid crystal a attached is determined by the viscosity and surface tension of the liquid crystal a and the diameter of the liquid crystal pulling pin 21.

The amount of attached liquid crystal may be adjusted during the process of moving the liquid crystal pulling pin 21 onto the substrate 11. In short, the liquid crystal lifting pin 21 is pulled up from the liquid crystal reservoir A and the liquid crystal is removed from the substrate 11.
The excess liquid crystal a may be dropped during the time until it comes into contact with the upper surface of the liquid crystal.

However, if the excess liquid crystal a is dropped during the time when the liquid crystal pulling pin 21 is moved horizontally above the substrate 11, the dropped liquid crystal will be wasted. It is preferable to temporarily stop the liquid crystal pulling pin 21 above the liquid crystal bath A and return the dropped excess liquid crystal a to the liquid crystal reservoir A. Further, when the tip of the liquid crystal pulling pin 21 is brought into contact with the upper surface of the liquid crystal enclosed area of the substrate 11, the liquid crystal a, which has been spherically attached to the tip of the liquid crystal pulling pin 21 due to surface tension, is transferred onto the surface of the substrate 11. The amount of liquid crystal a transferred onto the surface of the substrate 11 is the same constant amount as the amount of liquid crystal attached to the liquid crystal pulling pin 21.

After this, the liquid crystal pulling pin 21 is raised and moved laterally onto the liquid crystal tray 20 again, and the above operation is repeated as shown in FIG. 2 to pull up the liquid crystal a of the liquid crystal reservoir A in the liquid crystal tray 20. A fixed amount of the liquid crystal is transferred and supplied to the same liquid crystal sealed area of the substrate 11 by the pin 21. Note that when transferring and supplying the liquid crystal a to the same liquid crystal sealed area of the substrate 11 for the second and subsequent times, the contact position of the liquid crystal pulling pin 21 to the substrate 11 is changed each time, and the liquid crystal a is scattered over a wide range in the liquid crystal sealed area. to transfer liquid crystal a. Even if the transfer position of the liquid crystal a is changed by changing the horizontal movement position of the pin holder 22 onto the substrate 11,
This may be performed by moving the substrate 11 back and forth, left and right in parallel.

In addition, the number of times of this liquid crystal supply operation is determined by the target supply amount (1
The amount of liquid crystal sealed in one liquid crystal element) is adjusted using the liquid crystal pulling pin 2.
1 (in this embodiment, 2) and the amount of liquid crystal transferred by one liquid crystal pulling pin 21. If the amount of liquid crystal adhered to the tip of the 21 and transferred to the substrate 11 is selected to be equal to the target supply amount, the target supply amount can be achieved by repeating the liquid crystal supply operation a predetermined number of times. Liquid crystal a can be supplied to one liquid crystal enclosure area.

After supplying the target supply amount of liquid crystal a to one liquid crystal sealed region of the substrate 11 in this way, the above-mentioned liquid crystal supply operation is repeated to supply the target amount of liquid crystal a to the liquid crystal sealed region of the other liquid crystal element portion of the substrate 11. Quantity of liquid crystal a is supplied.

3 and 4 show the state in which the target supply amount of liquid crystal a has been supplied to the liquid crystal filling area of each liquid crystal element portion on the surface of the substrate 11, and the liquid crystal a is spread over a wide area in each liquid crystal filling area. It is scattered and attached to.

After supplying the target supply amount of liquid crystal a to the liquid crystal filling area of each liquid crystal element portion on the surface of the substrate 11 in this manner, another liquid crystal a is placed on the substrate ll in a vacuum atmosphere as shown in FIG. After stacking two substrates 13 and bonding both substrates 11.13 with a sealant 12, both substrates 11.13 are cut outside of the sealant 12 to form individual liquid crystal elements as shown in FIG. You can separate it into Note that the substrate 11
The liquid crystal a dotted and attached to the liquid crystal enclosure area of each liquid crystal element portion on the surface is removed by stacking both substrates 11.13 in a vacuum atmosphere and bonding them with the sealing material 12. The liquid crystal layer is pushed out and spread over the entire liquid crystal sealed area, forming one liquid crystal layer as shown in FIG.

That is, in the above liquid crystal supply method, the liquid crystal pulling pin 21 is immersed in the liquid crystal layer A in the liquid crystal tray 20, and then the liquid crystal pulling pin 21 is pulled up from the liquid crystal layer A and the tip thereof is attached to the substrate 11.
The liquid crystal a, which is attached to the liquid crystal pulling pin 21 and pulled up from the liquid crystal layer A, is transferred and supplied onto the substrate 11.

Now, considering the conditions that determine the amount of liquid crystal supplied per time by the liquid crystal pulling pin 21, these conditions are: ■ Immersion length of the liquid crystal pulling pin 21 in liquid crystal bath A ■ Liquid crystal pulling from liquid crystal bath A Pulling speed of the pin 21 ■ Pull up the liquid crystal pulling pin 21 from the liquid crystal layer A and remove the substrate 11.
The time it takes to contact the top surface, the time that the liquid crystal pulling pin 21 is in contact with the substrate 11, and the diameter of the liquid crystal lifting pin 21 can be considered, but among these, the following factors have the greatest effect on the amount of liquid crystal supplied: and ■. This means that even if the length of immersion of the liquid crystal pulling pin 21 into the liquid crystal layer A (conditions in ■) changes to some extent, the amount of liquid crystal a that will eventually adhere to the tip of the liquid crystal pulling pin 21 and be carried onto the substrate 11 will change. can be made constant by controlling the bow raising speed of the liquid crystal pulling pin 21 in (2) above and the time until the liquid crystal pulling pin 21 in (2) comes into contact with the substrate 11. If the amount of adhered liquid crystal is constant, the amount of liquid crystal transferred to the substrate 11 is also constant, so even if the time period during which the liquid crystal pulling pin 21 is in contact with the substrate 11 (condition 2) changes, the amount of liquid crystal transferred to the substrate 11 is constant.
The amount of liquid crystal supplied to No. 1 does not change.

Therefore, in the above liquid crystal supply method, the liquid crystal pulling pin 2
1 so that the amount of liquid crystal attached to the tip of the liquid crystal pulling pin 21 and transferred to the substrate 11 is equal to the target supply amount to be supplied to one liquid crystal filling area on the surface of the substrate 11. At the same time, it is only necessary to control the pulling speed of the liquid crystal pulling pin 21 and the time until the liquid crystal pulling pin contacts the top surface of the substrate to be constant, and it is not particularly difficult to control these, so according to the above liquid crystal supply method. , it is possible to always supply a constant amount of liquid crystal onto the substrate with simple control. However, the condition (2) above is such that liquid crystal is replenished to the liquid crystal tray 20 according to changes in the bath surface of the liquid crystal layer A to keep the bath surface of the liquid crystal layer A almost constant, and the liquid crystal pulling pin 21 to the liquid crystal layer A is
It can be easily controlled by keeping the downward stroke constant, and the condition (■) can also be easily controlled by simply setting the time, so the conditions (■) and (2) above are also controlled. However, it does not become difficult to control the amount of liquid crystal supplied.

In the above embodiment, two liquid crystal pulling pins 21 are used, but the number of liquid crystal lifting pins 21 may be one or three or more. For example, by reducing the number of times the liquid crystal supply operation described above is performed, efficient liquid crystal supply can be achieved. Further, in the above embodiment, the substrate 1 has an area equivalent to a plurality of liquid crystal elements.
Although the case where liquid crystal a is supplied to the substrate 1 has been described, the liquid crystal supply method of the present invention can also be used to supply liquid crystal to a substrate having an area equivalent to one liquid crystal element.

[Effects of the Invention] The method of supplying liquid crystal to a substrate for a liquid crystal element of the present invention includes attaching liquid crystal in a liquid crystal bath to a liquid crystal pulling pin and pulling it up from the liquid crystal bath;
The liquid crystal attached to this liquid crystal pull-up pin is transferred and supplied onto the substrate by bringing the tip of the liquid crystal pull-up pin into contact with the top surface of the substrate, so a fixed amount of liquid crystal can always be placed on the substrate with simple control. can be supplied.

[Brief explanation of drawings]

1 to 6 show an embodiment of the present invention, and FIGS. 1 and 2 are liquid crystal supply operation diagrams, and FIGS.
The figure shows a cross-sectional view and a plan view of the board after supplying liquid crystal.
FIG. 5 is a sectional view of a substrate to which liquid crystal has been supplied and another substrate bonded together, and FIG. 6 is a sectional view of a separated liquid crystal element. FIG. 7 is a diagram showing a conventional liquid crystal supply method. DESCRIPTION OF SYMBOLS 11... Substrate, 12... Sealing material, 20... Liquid crystal saucer, A... Liquid crystal bath, a... Liquid crystal, 21... Liquid crystal pulling pin, 22... Pin holder.

Claims (1)

[Claims] In a method of supplying liquid crystal to a liquid crystal enclosure area surrounded by a frame-shaped sealing material of a liquid crystal element substrate, a vertical rod-shaped liquid crystal pulling pin is immersed in a liquid crystal bath, and then the liquid crystal pulling pin is pulled up from the liquid crystal bath and its tip is supplying liquid crystal to a substrate for a liquid crystal element, characterized in that the liquid crystal is brought into contact with the upper surface of the liquid crystal sealed area of the substrate, and the liquid crystal that is attached to the liquid crystal pulling pin and pulled up from the liquid crystal bath is transferred and supplied onto the substrate. Method.