JPH05333300A - Production of liquid crystal display element - Google Patents

Abstract

PURPOSE:To shorten the time for injection of a liquid crystal by compressing and curing a sealing material after injecting the liquid crystal. CONSTITUTION:Many electrodes are formed on a pair of transparent substrates 1 and 4. The sealing material 2 for sticking a pair of the transparent substrates 1 and 4 is applied on the one transparent substrate 1. The other transparent substrate 4 is superposed on the sealing material 2. The liquid crystal 6 is injected into the spacing 5 between a pair of the transparent substrates 1 and 4 enclosed by the sealing material 2. The transparent substrates 1 and 4 are pressurized in the direction where these substrates face each other to compress the sealing material 2 in such a manner that the spacing 5 attains a prescribed value. The display element is so constituted that the sealing material 2 is cured after the liquid crystal injection port 3 of the sealing material 2 is sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly to a method for injecting liquid crystal and curing a sealing member.

Liquid crystal display devices, which have been used in various fields in recent years due to their features such as thinness, light weight, and low power consumption, are required to have further improved display quality and cost reduction. , New technology is needed to produce high quality products with good yield.

[0003]

2. Description of the Related Art FIGS. 3 and 4 are explanatory views (No. 1 and No. 2) of main manufacturing steps of a conventional liquid crystal display device.

As shown in FIG. 3 (a), on the surface of the transparent substrate 1 on which a large number of transparent electrodes and the like are patterned, a seal member 2 having a liquid crystal injection port 3 opened on one side is provided on the periphery of the surface. Apply along. A thermosetting resin or a photocurable resin mixed with glass fiber powder is used for the seal member 2 applied by using a dispenser or the like.

Next, as shown in FIG. 3B, the transparent substrate 4 on which a large number of transparent electrodes and the like are patterned is attached to the sealing member 2.
Then, the substrate 4 is pressed toward the substrate 1, and the seal member 2 is cured in a compressed state so that the gap between the substrates 1 and 4 becomes a dimension when the liquid crystal display element is completed, for example, 4 to 7 μm.

Next, the facing gap 5 between the substrates 1 and 4 surrounded by the seal member 2 is evacuated to immerse the injection port 3 in the liquid crystal 6 as shown in FIG. The liquid crystal 6 is injected (vacuum filling).

After that, as shown in FIG. 4B, the inlet 3
Is hermetically sealed with the sealing material 7, and the liquid crystal injection step of the liquid crystal display element 8 is completed. In the liquid crystal display element 8, since the liquid crystal 6 has high viscosity and the gap 5 is extremely narrow, it takes 2 to 3 hours to inject the liquid crystal into a display element having a display area of, for example, a B5 plate.

[0008]

As described above,
Since the conventional liquid crystal display element 8 requires a long time for the liquid crystal injection process, there is a problem in that the liquid crystal injection process is stagnant, the throughput is low, and the production efficiency cannot be improved.

[0009]

According to the method of the present invention, a large number of electrodes are formed on a pair of transparent substrates 1 and 4, and a pair of transparent substrates 1 is formed.
The seal member 2 for adhering 4 and 4 is applied to the transparent substrate 1, and the transparent substrate 4 is placed on the seal member 2.

Next, the liquid crystal 6 is injected into the gap 5 between the pair of transparent substrates 1 and 4 surrounded by the seal member 2 and the pair of transparent substrates 1 and 4 is pressed in the opposing direction to bring the gap 5 to a predetermined value. The sealing member 2 is compressed so that the liquid crystal injection port 3 of the sealing member 2 is sealed, and then the sealing member 2 is cured.

Furthermore, when injecting the liquid crystal 6, the pair of transparent substrates 1 and 4 and the liquid crystal 6 are heated to a temperature exceeding the phase transition temperature of the liquid crystal 6, and a thermoplastic resin is used for the seal member 2.

[0012]

According to the above means, the seal member is compressed and cured after the liquid crystal is injected. Therefore, the gap between the substrates at the time of injecting the liquid crystal is larger than that in the conventional method of injecting the liquid crystal after compressing and curing the sealing member, and therefore the injecting of the liquid crystal becomes easy and the required time is shortened.

Further, the liquid crystal injection time can be further shortened by heating the liquid crystal to its phase transition temperature, or by using a thermoplastic resin for the seal member and utilizing its thermal expansion to widen the substrate gap at the time of liquid crystal injection. .

[0014]

1 and 2 are explanatory views (No. 1 and No. 2) of main steps of a method of manufacturing a liquid crystal display device according to an embodiment of the present invention.

As shown in the perspective view of FIG. 1 (a), a transparent substrate 1 on which a large number of transparent electrodes and the like are patterned is coated with a seal member 2 having a liquid crystal injection port 3 on one side, After pre-curing the seal member 2 at, for example, about 80 ° C., a large number of transparent electrodes and the like were patterned on the seal member 2 as shown in the perspective view of FIG. 1B and the side view of FIG. The transparent substrate 4 is overlaid, the transparent substrate 4 is airtightly adhered to the sealing member 2, and the transparent substrate 4 is sealed so that the gap between the substrates 1 and 4 is larger than that when the liquid crystal display element is completed, for example, about 7 μm. Press 2.

Next, after the inside of the facing gap 5 between the substrates 1 and 4 surrounded by the seal member 2 is evacuated in the same manner as in the conventional method, for example, in the chamber of the liquid crystal injecting apparatus, it is shown in the front view of FIG. As described above, when the injection port 3 is immersed in the liquid crystal 6 placed in the container 9 and the pressure in the chamber is gradually returned to the atmospheric pressure, the gap 5 is formed.
The liquid crystal 6 is injected (filled) into the.

Next, the substrates 1 and 4 are placed in a vacuum pack and the inside of the vacuum pack is decompressed to compress the gap 5 to a size when the liquid crystal display element is completed. Alternatively, as shown in the side view of FIG. When the substrates 1 and 4 are sandwiched by a pair of pressure plates 11 and the substrates 1 and 4 are pressed in the opposite directions to compress the gap 5 to the size when the liquid crystal display element is completed, the extra liquid crystal 6 injected into the gap 5 is discharged from the injection port 3.

After that, as shown in the partially cutaway front view of FIG. 2B, the injection port 3 is hermetically sealed with a sealing material 7, and the sealing member 2 is cured, for example, heated at 130 ° C. for about 1 hour or ultraviolet rays. When the sealing member 2 is cured by irradiating with light, the liquid crystal display element 12 by the method of the present invention is completed.

The liquid crystal 6 is highly viscous at room temperature, but when heated above the phase transition temperature (ni point) of about 80 to 120 ° C., the viscosity sharply decreases. Therefore, the seal member 2
A photo-curable resin or a thermosetting resin that cures at a temperature appropriately higher than the phase transition temperature of the liquid crystal 6 is used as the liquid crystal 6.
When heated to a temperature slightly above the phase transition temperature of 100 ° C., for example, the injection speed of the liquid crystal 6 becomes faster than that at room temperature, and the injection time can be shortened by about 50%.

Further, if a thermoplastic resin is used for the seal member 2 instead of the thermosetting or photo-curing resin, the substrate gap before liquid crystal injection can be increased by utilizing the thermal expansion coefficient of the thermoplastic resin. This makes it possible to shorten the injection time of the liquid crystal 6 as compared with the case where the thermosetting or photocurable resin is used for the seal member 2.

[0021]

As described above, according to the method of the present invention, the liquid crystal injection time for a narrow substrate gap can be shortened to about half that of the conventional method, and the liquid crystal display device manufacturing process (liquid crystal injection process) can be performed. Throughput is improved, and the effect of improving productivity, shortening delivery time, and reducing costs is remarkable.

[Brief description of drawings]

FIG. 1 is an explanatory view (No. 1) of main manufacturing steps of a liquid crystal display element that is an embodiment of the present invention.

FIG. 2 is an explanatory view (No. 2) of main manufacturing steps of the liquid crystal display element which is the embodiment of the present invention.

FIG. 3 is an explanatory view (No. 1) of main manufacturing steps of a conventional liquid crystal display element.

FIG. 4 is an explanatory view (No. 2) of the main manufacturing steps of the conventional liquid crystal display element.

[Explanation of symbols]

 1 and 4 are transparent substrates 2 are seal members 3 are liquid crystal inlets 5 are substrate gaps 6 are liquid crystals

Claims (3)

[Claims] 1. A seal member for forming a large number of electrodes on a pair of transparent substrates (1, 4) and attaching the pair of transparent substrates (1, 4) to each other.
(2) is applied to one side (1) of the transparent substrate, and the seal member
The other side (4) of the transparent substrate is placed on (2), and the sealing member
The liquid crystal (6) is injected into the gap (5) between the pair of transparent substrates (1,4) surrounded by (2), and the pair of transparent substrates (1,4) is pressed in the opposite direction to The seal member (2) is compressed so that the gap (5) becomes a predetermined value, and the liquid crystal injection port (3) of the seal member (2) is compressed.
A method for manufacturing a liquid crystal display element, which comprises: after sealing the sheet, the sealing member (2) is cured. 2. When the liquid crystal (6) is injected, the pair of transparent substrates (1, 4) and the liquid crystal (6) are heated to a temperature exceeding the phase transition temperature of the liquid crystal (6). The method for manufacturing a liquid crystal display element according to claim 1. 3. The method for manufacturing a liquid crystal display device according to claim 1, wherein a thermoplastic resin is used for the seal member (2).