JPS59164528A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To prevent mixing of bubbles in liquid crystals and to enhance productivity by forming the inlet of liquid crystals to be sealed afterward between the electrode substrates of the end of a liquid crystal casing and a film treated for orienting the crystals on the liquid crystal side of said substrate. CONSTITUTION:Light transmitting segment electrodes 1a are formed on an upper electrode substrate 2a made of a light transmitting glass plate, and a polyimide type resin film is adhered to the area A of the upper face of the substrate 2a also including the part on which the inlet 4 of liquid crystals to be fed and sealed afterward. The surface of this film is rubbed, e.g. in the a-a' direction to form a liquid crystal orienting film 9. On the other hand, a light transmitting common electrode 1b is formed on a lower electrode substrate 2b of a light transmitting glass plate opposite to the upper substrate 2a, and a liquid crystal orienting film 10 of the polyamide type resin rubbed, e.g. in the b-b' direction is formed on the area B of the surface of the substrate 2b including the inlet 4 part, too.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a liquid crystal display element, and particularly to the structure of a liquid crystal filling port.

[Background of the invention]

In general, a liquid crystal display element has translucent segment electrodes 1a on opposing surfaces, as shown in FIGS. 1(a) and 1(b).
, two transparent electrode substrates 2m on which a common electrode 1b is formed.
, 2b facing each other and pasting the peripheral parts with sealant 3,
After inserting the electrode substrates 2ay 2b into a liquid crystal tank 7 having a liquid crystal filling opening 4 formed in the portion where the sealing material 3 is not applied and filling the TN liquid crystal 6 by, for example, a coil filling method, as shown in FIG. As shown, the liquid crystal filling port 4 is sealed using an adhesive 8.

However, according to the liquid crystal encapsulation method as described above,
Air bubbles generated when the liquid crystal 6 is sealed in the envelope 5 are also absorbed at the same time, resulting in a disadvantage that the air bubbles are mixed into the envelope and reduce the yield of liquid crystal display elements.

[Purpose of the invention]

Therefore, the present invention has been made in view of the above-mentioned conventional problems, and its purpose is to provide a liquid crystal display element that eliminates the inclusion of air bubbles when liquid crystal is filled in and makes it possible to improve productivity. There is a particular thing.

[Summary of the invention]

In order to achieve such an object, the liquid crystal display element according to the present invention preferably includes a liquid crystal alignment film provided on at least one of the electrode substrates constituting the liquid crystal injection port. The wettability is used to prevent the inclusion of air bubbles that occur when liquid crystal is sealed.

That is, in a liquid crystal display element, a resin film is usually formed on an electrode substrate on which a translucent electrode is formed in order to orient the liquid crystal, and the surface of the resin film is rubbed with a cloth or the like using a so-called rubbing process. By applying this, an alignment film that orients the liquid crystal was formed. Therefore, the inventors evaluated the wettability of the liquid crystal on the surface of the alignment film subjected to the rubbing treatment using the contact angle, and obtained the results shown in Table 1 below.

Table 1 Based on these results, we focused on the fact that liquid crystal has higher wettability on the alignment film surface that has been subjected to rubbing treatment than when no rubbing treatment is applied. A treatment membrane is provided.

[Embodiments of the invention]

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

FIGS. 4(a) and 4(b) are exploded configuration diagrams of essential parts for explaining an example of a liquid crystal display element according to the present invention, and the same symbols as those in the above-mentioned figures are the same elements, so the explanation thereof will be omitted. do. In the same figure, first, as shown in the same figure (,), a transparent segment electrode 4 is formed on an upper electrode substrate 2 made of a transparent glass plate, and the upper surface thereof and the liquid crystal seal described above are A polyimide resin film is formed on the surface of the polyimide resin film, for example, in the region that also includes the entrance 4 formation site, that is, in the region A surrounded by the dotted line shown in the figure (,). 'The liquid crystal alignment film 9 is formed by applying two-ping processing in the force direction. On the other hand, as shown in FIG. 2(b), a lower electrode substrate 2b made of a transparent glass plate facing the upper electrode substrate 2a has a transparent common electrode 1b formed thereon, and the upper surface of the lower electrode substrate 2b and the above-mentioned A polyimide resin film is deposited in the region that also includes the liquid crystal filling port 4 formation site, that is, region B surrounded by the dotted line, and the surface of the polyimide resin film is subjected to, for example, b-b' force direction rubbing treatment. A liquid crystal alignment film 10 is formed. Both electrode substrates 2&, 2b configured in this way are used as segment electrodes IJL.

An epoxy sealing material 3 was applied to the peripheral portion so that the common electrodes 1b faced each other and sealed, thereby constructing an envelope similar to the configuration shown in FIG. 2.

When the TN liquid crystal 6 is sealed from the liquid crystal filling port 4 into the envelope constructed in this manner by the coil filling method shown in FIG. 2, 60 molecules of liquid crystal are formed on the inner surface of each liquid crystal filling port 4. The alignment films 9 and 10 are continuously drawn in and sealed along the liquid crystal alignment direction while being wet. As a result, the incidence of air bubbles entering the liquid crystal envelope was 0. ! We were able to keep it below 1. Incidentally, in a conventional liquid crystal envelope without an alignment film in the liquid crystal filling port 4 as shown in FIG. 2, the incidence of bubble inclusion is 1 to 2%.

Further, as another embodiment of the liquid crystal display element according to the present invention,
The electrode substrates 2m and 2b are made of polyethylene terephthalate film, the sealing material 3 is made of polyester resin, and the rest is constructed in the same manner as in the first embodiment, which prevents air bubbles from entering the liquid crystal envelope. The incidence was 1-3%. In fact, in conventional liquid crystal envelopes without an alignment film in the liquid crystal sealing port, the incidence of air bubbles was 5 to 10%.

Further, as yet another embodiment of the liquid crystal display element according to the present invention, electrode substrates 2m and 2b are placed between two polyethylene terephthalate films I A and I B uniaxially stretched in the direction of arrow C as shown in FIG. It goes without saying that the same effect as described above can be obtained even if a translucent plastic film formed with a polarizer 11 interposed therein, which also serves as a so-called polarizing plate, can be used.

In addition, in the above-mentioned embodiment, the liquid crystal alignment films 9 and 10 formed on the surface of the electrode substrate including the liquid crystal filling port forming region are as follows.
Although the case where the polyimide resin film is formed by rubbing the surface thereof has been described, the present invention is not limited to this, and when the electrode substrate is formed of a glass plate,
It goes without saying that the same effect as described above can be obtained even by using an alignment film formed by the so-called oblique vapor deposition method in which silicon oxide is vapor-deposited on the surface from an oblique direction.

〔Effect of the invention〕

As explained above, according to the liquid crystal display element according to the present invention, by providing a liquid crystal alignment treatment film on at least one of the electrode substrates constituting the liquid crystal injection port, it is possible to transfer the liquid crystal into the liquid crystal display element without increasing the number of steps. Since the generation rate of air bubbles can be significantly reduced, the yield of liquid crystal display elements can be improved, and productivity can be greatly improved.

[Brief explanation of drawings]

1 to 3 are diagrams for explaining an example of a conventional liquid crystal display element, and FIG. 4(a). (b) is a diagram for explaining one embodiment of the liquid crystal display element according to the present invention, and FIG. 5 is a perspective view of essential parts showing another embodiment of the electrode substrate related to the liquid crystal display element according to the present invention. IA@... polyethylene terephthalate film, 2
a#...upper electrode substrate, 1B...polyethylene terephthalate film, 2b...lower electrode substrate, h.
...Segment electrode, lb φ...Boku common xi,
3... Sealing material, 4... Liquid crystal sealing port, 5...
・Liquid crystal 4mtlt-e・kai・-TN liquid crystal, 70.・, Liquid crystal tank, 8・-.・Adhesive, 9, 10...Alignment film, 1E...Polarizer. Figure 1 Figure 2 Figure 4 Figure 5

Claims (1)

[Scope of Claims] 1. A liquid crystal envelope is constructed by sealing a pair of electrode substrates having translucent electrodes on opposing surfaces facing each other with a sealing material interposed in the periphery, and an end portion of the envelope In the liquid crystal display element, a liquid crystal sealing port is provided in a part between the electrode substrates, liquid crystal is sealed from the liquid crystal sealing port into the liquid crystal envelope, and then the vaginal liquid crystal sealing port is sealed. 1. A liquid crystal display element comprising a liquid crystal alignment film provided on at least one electrode substrate constituting the element. 2. The liquid crystal display element according to claim 1, wherein a polyethylene terephthalate film is used for the electrode substrate. 3. The liquid crystal display element according to claim 1, wherein the electrode substrate is a polarizing plate having a polyethylene terephthalate film as a support. 4. The liquid crystal display element according to claim 1, wherein the electrode substrate is a polarizing plate having a uniaxially stretched polyethylene terephthalate film as a support.