JPS59164529A - Manufacture of liquid crystal display device - Google Patents

Abstract

PURPOSE:To facilitate mass production of a liquid crystal display element without causing destruction of it by removing the surrounding part of each inlet of the liquid crystals of both plastic substrates before pasting both substrates in advance. CONSTITUTION:Each liquid crystal inlet part to be later sealed of a liquid crystal display element is formed in rows on both ends of plastic films by cutting off the part of both ends of the films, as shown with hatches except a part for forming the inlet part 1a before pasting both substrates to each other to form the two plastic films having each symmetrical protrusion on both ends in rows. Both these subtrates are pasted to each other so as to allow both electrodes 2a, 2b to face each other exactly. Each polarizing plate is adhered to the outer surface of each of the upper and lower substrates so as to cross the absorption axis at right angles to each other, and since each segment is cut off along the cutting lines as shown with the dotted lines, enabling mass production of the casings 4 of the liquid crystal display devices. After the casings 4 are evacuated and the tops of the inlets of liquid crystals are inserted into the liquid crystals 5, and they are returned to atmospheric pressure, they are injected and the inlets are sealed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing a liquid crystal display element, and particularly to a multi-manufacturing process for a liquid crystal display element using a plastic film substrate.

[Background of the invention]

Conventionally, when manufacturing a liquid crystal display element, two counter electrode substrates each having a counter electrode formed in each of a large number of sections each corresponding to one liquid crystal display element are placed on a large substrate. A multi-manufacturing process is adopted in which the panels are placed facing each other and simultaneously bonded and solidified using a peripheral sealant, and then cut and divided into side sections. In this case, a liquid crystal display element that uses a glass plate as an electrode substrate is cut with a diamond cutter or a cutter that uses super steel, but a liquid crystal display element that uses a plastic film as an electrode substrate is cut with a cutting tool such as a press. Cutting is performed using a method using When a press mold is used, a method using a combination of grade blades called the Thomson type is usually widely used in order to avoid damaging individual element substrates.

However, according to such a cutting method, especially when two pieces of adhesively solidified counter electrode substrates are cut at the same time, stress is applied to the substrates, which causes the problem of peeling of the seal adhesive part of the liquid crystal display element. was there. In other words, plastic film has a lower elastic modulus than a glass plate, so it deforms when cut, and a large stress is applied to the area where the sealant is solidified.Especially, the seal adhesive area near the liquid crystal filling opening peels off when cut. There was a problem.

Furthermore, there is also the problem that debris from plastic cutting, dirt from the press blade, etc. adhere to the liquid crystal filling opening during cutting, and when liquid crystal is injected, the injected liquid crystal is contaminated, reducing the reliability of the device. Furthermore, after liquid crystal is sealed in a liquid crystal display element using a plastic film as a substrate, it is technically difficult to seal the liquid crystal sealing opening with an organic or inorganic sealant like a glass plate. A sealing method using thermocompression bonding by thermally melting the substrate has been adopted, but since the liquid crystal filling port is located close to the element body, in this method, when the sealing material near the liquid crystal filling port is crimped, There was a problem in that the stress caused by υ caused peeling or cracking, which could cause air bubbles to enter the element.

[Purpose of the invention]

Therefore, the present invention has been made to eliminate the drawbacks of the prior art described above, and its purpose is to:
It is now possible to easily mass-produce liquid crystal display elements that use plastic film as a substrate through a multi-manufacturing process without causing damage to the element or getting dirt on the liquid crystal filling opening. An object of the present invention is to provide a method for manufacturing a liquid crystal display element.

[Summary of the invention]

In order to achieve this object, the present invention is such that the peripheral portion of the liquid crystal filling opening of the side substrate is removed in advance before pasting the plastic film substrate together.

[Embodiments of the invention]

Next, embodiments of the present invention will be described in detail using the drawings.

FIGS. 1 to 5 are explanatory diagrams of main parts showing an example of a method for manufacturing a liquid crystal display device according to the present invention. In these figures,
First, as shown in the plan view in Figure 1, a single shaft with a thickness of approximately 250 μm and a size of 200 x 100 mm! Two sheets of stretched polyethylene terephthalate film 1 are prepared. and,
As shown in the plan view in FIG. 2, when the liquid crystal inlet portions of the liquid crystal display element are arranged and formed on both ends of the film 1, a peripheral portion 1b shown as a hatched area excluding the liquid crystal inlet forming portion 1a is formed. The portion 1c is cut and removed by pressing or milling, and two films 1' having symmetrical protrusions formed at both ends are manufactured and used as upper and lower substrates. In this case, the length L of the liquid crystal injection port forming portion 1a is formed to be long to some extent. Next, in Figure 3(a) t (
As shown in the plan view in b), transparent conductive films are formed into desired shapes at predetermined positions on the opposing surfaces of the upper substrate 1A and the lower substrate 1B made of the film 1', respectively, by a well-known photoetching method or the like. Segment electrodes 2& and common electrodes 2b are formed, and these electrodes 2a,
An alignment film made of a material that can be processed at low temperature, such as PVA, is formed on the upper substrate IA and the lower substrate 1B on which the patterns 2b and 2b are formed, and subjected to rubbing treatment, and after the alignment treatment is performed so as to be orthogonal to each other, the lower substrate 1B is formed. A sealing agent 3 is printed and coated in a frame shape at a predetermined position on the top, and the two electrodes 2 are attached to the upper substrate 1 and the lower substrate 1B.
The sealant 3 is pasted together so that a and 2b accurately face each other, and the sealant 3 is cured while being pressed with a roll (not shown) or the like. In this case, the protrusions of the liquid crystal sealing port forming portions 1a of the upper and lower substrates IA and 1B are aligned and bonded without shifting from each other.

After that, polarizing plates are adhesively arranged on the outer surfaces of the upper and lower substrates IA and IB so that their light absorption axes are perpendicular to each other, and each is cut by pressing or milling along the cut portions shown by dotted lines in FIG. By cutting and separating each section, as shown in FIG. 5, liquid crystal display element envelopes 4 having a long liquid crystal filling opening 4a can be produced in large quantities. As shown in FIG. 5, the envelope 4 thus formed is made into a vacuum state in a vacuum atmosphere, and then the tip of the liquid crystal filling opening 4a is inserted into the liquid crystal 5. The liquid crystal is injected by inserting the tube and returning it to atmospheric pressure. After that, A-A of the liquid crystal filling port 4a
' The liquid crystal display element is completed by sealing the ' part by heat melting using thermocompression bonding.

According to such a method, there is no need to cut the peripheral portion of the liquid crystal filling port 4a to form the liquid crystal filling port 4a, so there is no damage to the envelope 4.

〔Effect of the invention〕

As explained above, according to the method of manufacturing a liquid crystal display element according to the present invention, by removing the peripheral part of the liquid crystal sealing opening of both plates in advance, it is possible to individually In the cutting step of dividing into elements, it becomes possible to divide into individual elements without cutting again the liquid crystal sealing opening formed by adhering and solidifying the sealant. Therefore, there is no destruction of the device due to impact when cutting the liquid crystal filling port, and liquid crystal display devices using plastic films can be easily mass-produced. In addition, since it is not necessary to cut the liquid crystal filling port, dirt does not adhere to the liquid crystal filling port, and excellent effects such as obtaining a high-quality liquid crystal display element can be obtained.

[Brief explanation of drawings]

1 to 5 are diagrams for explaining an example of a method for manufacturing a liquid crystal display element according to the present invention. 1.--Polyethylene terephthalate film, 1'
...Film, 1 & @...Liquid crystal sealing port forming part, 1b, 1e...periphery, 1 person---upper substrate, 1B+1...lower substrate, 2a... Segment electrode, 2b... common electrode, 3... sealant,
4... envelope, 4a... liquid crystal sealing port, 5...
·liquid crystal.

Claims (1)

[Claims] 1. Two plastic film substrates each having an electrode in a plurality of sections each corresponding to one liquid crystal display element are pasted together, and a liquid crystal is placed in the gap between the substrates for each section. In the manufacturing method of a liquid crystal display element, in which the liquid crystal display element is sealed and then cut into individual liquid crystal display elements by cutting into each section, the peripheral parts of the liquid crystal filling opening of both the substrates are removed in advance before pasting the two substrates together. 2. Manufacturing a liquid crystal display element according to claim 1, characterized in that a uniaxially stretched polyethylene terephthalate film is used as the plastic film substrate. Method.