JPH10221666A - Manufacture of liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time for producing a large liquid crystal display element by discharging liquid crystal onto substrates where a sealing material is arranged by means of a discharge device and adhering the two substrates. SOLUTION: A polyimide precursor is coated on the two substrates with an electrode by a spin-coating method, calcining is executed and, after that, rubbing is executed so as to execute an orienting processing. A spacer 7 is formed by a screen printing method in the periphery of one of the substrates through the use of an adhesive resin by mixing silica-particulates with an epoxide resin adhesive resin. Previlinary calcining is executed in order to remove a volatile components in the adhesive resin and, after that, polystyrene beads are disperesed on the substrates 6. Liquid crystal is discharged on the whole surface of the substrate 6 whose four sides obtained in this way by the spacer 7 consisting of the adhesive resin by the nozzle of an ink jet device. Then, the substrate 6 is adhered to the opposite substrate in a vacuum, the uniformity and thickness of the whole surface is finely adjusted and, after that, a system is put into a drier and dried and hardened.

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 manufacturing a liquid crystal display device comprising two electrodes, a substrate with an alignment film, a spacer sandwiched between the substrates, and a liquid crystal surrounded by these members. In the method for manufacturing a liquid crystal display element, a liquid crystal is discharged using a discharge device, and a predetermined amount of liquid crystal is disposed in a portion surrounded by a spacer. And a method for manufacturing a liquid crystal display device in which the above is shortened and improved.

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices having features such as thinness, light weight, and low power consumption have been actively used as display devices for OA devices such as Japanese word processors and desktop personal computers. Here, the replacement of liquid crystal display elements with CRTs is progressing, and wall-mounted televisions are on the verge. Accordingly, the size of the liquid crystal display device has been increased, and a device having a diagonal length of 1 m or more has come to be considered.

FIG. 1 is a sectional view of a liquid crystal display device. In the figures, reference numerals 1 and 2 denote a substrate with electrodes and an alignment film, 3 denotes a spacer, 4 denotes a liquid crystal, and 5 denotes a sealing material (an inlet before liquid crystal is introduced). The thickness of the spacer is very thin, 5 to 6 microns or less. The conventional liquid crystal display element has such a configuration. The method for filling the liquid crystal was as follows. First, a liquid crystal display element (hereinafter, referred to as a liquid crystal display cell) before sealing is sufficiently degassed in a vacuum, and then the injection port is sealed with liquid crystal. Such a liquid crystal display cell is returned to the atmosphere, and is filled by utilizing a pressure difference between the inside and outside of the liquid crystal display cell and surface tension. For this reason, it takes much time when the size of the liquid crystal display element increases. A substrate with a diagonal length of 1 m or more would take more than one day, which is not practical in manufacturing.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to provide a method capable of shortening the manufacturing time of a large-sized liquid crystal display device and manufacturing it in a practical time. It was done to do so.

[0005]

In order to solve the above-mentioned problems, a method of manufacturing a liquid crystal display device according to the present invention comprises the steps of:
In a method of manufacturing a liquid crystal display element including first and second substrates having an alignment film, a spacer sandwiched between the substrates, and a liquid crystal surrounded by these members, sealing materials are provided on four sides of one of the substrates. And discharging the liquid crystal onto the substrate on which the sealing material is provided by a discharge device, and laminating two substrates.

Alternatively, a method of manufacturing a liquid crystal display device according to the present invention is characterized in that the discharge device of the above-described manufacturing method is an ink jet device.

First, a sealant is printed around one of the electrodes and the substrate with an alignment film by a method such as screen printing. A commercially available adhesive can be used as a sealing material,
It is preferable to use an adhesive in which gap holding particles are dispersed in order to maintain the thickness between the substrates and regulate the amount of liquid crystal. As the adhesive used for the sealant, both a thermosetting adhesive and a photocurable adhesive can be used.

Further, in the above-mentioned manufacturing method, after the sealing material is provided, the gap holding particles are dispersed on the substrate,
The spacing between the substrates can be kept uniform, which is still good.

In addition, the step of dispersing the gap holding particles by discharging the liquid crystal in which the gap holding particles are dispersed by the discharge device may be further omitted.

As the sealant, a thermosetting adhesive or a photocurable adhesive can be used. As the gap holding particles, plastic particles such as silica particles and polystyrene particles, and a thermoplastic resin around silica particles are used. Coated particles and the like can be used. After the above steps, in the portion surrounded by the substrate and the sealant thus obtained,
The liquid crystal is applied in a plane by the discharge device by the calculated amount. An ink jet device is preferable as the ejection device.

After bonding the thus obtained substrate and the other substrate, the adhesive is cured to obtain a liquid crystal display device. It is more preferable to perform the bonding under vacuum.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a liquid crystal display device according to the present invention will be described in detail with reference to FIGS. FIG. 3 is a conceptual diagram showing a step of discharging liquid crystal using a discharge device in the method for manufacturing a liquid crystal display element of the present invention, in which liquid is discharged from upper left to lower right on a substrate surrounded by spacers. FIG. In the figure, reference numeral 6 denotes a substrate with electrodes, 7 denotes a spacer, 8 denotes a liquid crystal, and 9 denotes a nozzle of a discharge device.

(Example 1) Two diagonal pieces of 50 cm (30 ×
Polyimide precursor SP7 on substrate with electrode of 40cm2)
40 (manufactured by Toray Industries, Inc.) was applied by spin coating, baked, and then subjected to an alignment treatment by rubbing.
Around this one substrate, 0.5% by weight of silica microparticles having a particle diameter of 6 microns was added to an epoxy resin-based adhesive (struct bond (XN-21-S, manufactured by Mitsui Toatsu Chemicals, Inc.)).
2m by screen printing using mixed adhesive
A spacer having a width of m was prepared. Preliminary baking was performed at 70 ° C. to remove volatiles in the adhesive, and then polystyrene beads having a particle size of 6 μm were sprayed on the substrate. A liquid crystal (SS) is formed on the entire surface of the substrate thus obtained, which is surrounded on four sides by a spacer made of an adhesive, by an inkjet apparatus.
After discharging -4020 (manufactured by Chisso Petrochemical Co., Ltd.), this substrate and the opposite substrate are bonded together in a vacuum, fine adjustment of the uniformity and thickness of the entire surface is performed, and then the resultant is put in a dryer at 120 ° C. and dried and cured. I let it. The injection time, which conventionally took 2 hours, is reduced to about 5 minutes, which is very effective.

(Embodiment 2) Two diagonals of 50 cm (30 ×
Polyimide precursor SP7 on substrate with electrode of 40cm2)
40 (manufactured by Toray Industries, Inc.) was applied by spin coating, baked, and then subjected to an alignment treatment by rubbing.
An epoxy resin-based adhesive (Structbond (XN-21-S, manufactured by Mitsui Toatsu Chemicals, Inc.)) is provided around the substrate.
Then, a spacer having a width of 2 mm was formed by a screen printing method using an adhesive obtained by mixing 0.5% by weight of silica microparticles of 6 μm. Preliminary firing at 70 ° C. was conducted to remove volatiles in the adhesive. A liquid crystal (SS-4020, Chisso Oil Co., Ltd.) obtained by mixing and dispersing 0.2% of 6-micron polystyrene beads by an ink jet apparatus on the entire surface of the substrate thus obtained, which is surrounded on four sides by spacers made of an adhesive. After discharge of (Chemical Co., Ltd.), this substrate and the opposing substrate were bonded together in a vacuum, and the entire surface was finely adjusted in uniformity and thickness. The injection time, which conventionally took 2 hours, is reduced to about 5 minutes, which is very effective. According to this method, the step of spraying the so-called gap agent on the polystyrene beads can be omitted.

(Embodiment 3) Two diagonals of 50 cm (30 ×
Polyimide precursor SP7 on substrate with electrode of 40cm2)
40 (manufactured by Toray Industries, Inc.) was applied by spin coating, baked, and then subjected to an alignment treatment by rubbing.
Using an adhesive obtained by mixing 0.5% by weight of 6-micron silica fine particles with a visible light curable adhesive (Alontite VL1303, manufactured by Toa Gosei Chemical Co., Ltd.) around the substrate,
A spacer was formed with a width of 2 mm by a screen printing method. A liquid crystal (SS-4020, SS-4020, 6 wt. After discharging (Chisso Petrochemical Co., Ltd.), the substrate and the counter substrate were bonded together in a vacuum, and the entire surface was finely adjusted in uniformity and thickness, and then exposed to visible light for curing. The injection time, which conventionally took 2 hours, is reduced to about 5 minutes, which is very effective. Further, according to this method, there are advantages that the liquid crystal is not exposed to a high temperature and that it is not exposed to ultraviolet rays.

As described above, the manufacturing method of the present invention is an excellent manufacturing method. However, there are almost no restrictions on the material of the alignment film, the kind of the adhesive, the kind of the liquid crystal, and the like, and the method can be applied to a wide range of materials. It is.

[0017]

As described above, according to the present invention, the manufacturing time of the liquid crystal display device can be shortened. In particular, it exerts its power in the production of a liquid crystal display element having a diagonal of 1 m or more.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a conventional liquid crystal display device.

FIG. 2 is a view showing a manufacturing process of a liquid crystal display device for explaining the present invention.

[Explanation of symbols]

 1 ... Electrode, substrate with alignment film 2 ... Electrode, substrate with alignment film (counter electrode) 3 ... Spacer 4 ... Liquid crystal 5 ... Sealant 6 ... Electrodes, substrate with alignment film 7 ··· Spacer 8 ··· Liquid crystal 9 ··· Nozzle of discharge device

Claims (7)

[Claims] 1. A method of manufacturing a liquid crystal display device comprising first and second substrates having electrodes and an alignment film on the surface, spacers sandwiched between the substrates, and liquid crystal surrounded by these members. Installing sealing material on four sides of the substrate,
A method of manufacturing a liquid crystal display element, comprising a step of discharging liquid crystal by a discharge device on a substrate on which the sealing material is provided, and a step of bonding two substrates. 2. A method for manufacturing a liquid crystal display element according to claim 1, wherein said discharge device is an ink jet device. 3. A method for manufacturing a liquid crystal display element according to claim 1, wherein said sealing material is made of an adhesive containing gap holding particles. 4. The method for manufacturing a liquid crystal display device according to claim 1, wherein after the sealing material is provided, gap holding particles are dispersed on the substrate. 5. A method for manufacturing a liquid crystal display element according to claim 1, wherein the liquid crystal in which the gap maintaining particles are dispersed is discharged by a discharge device. 6. A method for manufacturing a liquid crystal display element according to claim 3, wherein said sealing material comprises a thermosetting adhesive. 7. A method for manufacturing a liquid crystal display element according to claim 3, wherein said sealing material is made of a photocurable adhesive.