JP2004258556A - Method for manufacturing ferroelectric liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a ferroelectric liquid crystal display element, in which an end-sealing agent is filled in an end-sealing part without pressurizing the ferroelectric liquid crystal display element in a step before the end-sealing step after injecting the ferroelectric liquid crystal into the ferroelectric liquid crystal display element using the ferroelectric liquid crystal. <P>SOLUTION: In the method for manufacturing the ferroelectric liquid crystal display element comprizing placing a transparent substrate and a silicon back plane, both with display electrodes, opposite to each other while holding a specified gap via an adhesive formed so as to surround the display part and integrating them, injecting the ferroelectric liquid crystal from an injection port into an ultra thin space formed of the transparent substrate, the silicon back plane and the adhesive, removing an excessive ferroelectric liquid crystal in the vicinity of the injection port and subsequently end-sealing the injection port, the ferroelectric liquid crystal at an inlet of the injection port is removed by immersing at least the end-sealing part of the ferroelectric liquid crystal display element (in the vicinity of the inlet of the ferroelectric liquid crystal injection port) in a solvent before end-sealing, the end-sealing agent is filled in a part from which the ferroelectric liquid crystal is removed and subsequently is hardened. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a ferroelectric liquid crystal display device.
[0002]
[Prior art]
2. Description of the Related Art In recent years, a liquid crystal display element in which a nematic liquid crystal is filled and sealed from an injection port of an ultra-thin space composed of a transparent substrate and a silicon backplane or a pair of transparent substrates has been widely used and has high demand.
[0003]
The liquid crystal display element must prevent liquid crystal leakage from the injection port and impurity penetration under various environmental tests. For this reason, by filling the inlet of the injection port with a sealing agent, liquid crystal leakage and impurity penetration in the ultra-thin space are prevented. As a method, from the removal of the liquid crystal at the inlet of the injection port to the application of the sealing agent, the entire liquid crystal display element or only the vicinity of the injection port is pressurized, and the pressure is released after the application. A method of filling the inlet of the injection port with a sealing agent by changing the volume of the inside of the liquid crystal (filled with liquid crystal) or its sealing portion (near the inlet of the liquid crystal injection port), or heating the liquid crystal while injecting the liquid crystal while holding it under pressure. It has been common practice to discharge the solution until a certain amount is reached, apply a sealant to the inlet, seal it, cool it, and then suck the sealant into the inlet. (For example, see Patent Document 1)
[0004]
[Patent Document 1]
JP-A-2001-83533 (page 4, FIG. 3)
[0005]
[Problems to be solved by the invention]
If the liquid crystal is a ferroelectric liquid crystal, the ferroelectric liquid crystal molecules have a layer structure and are oriented on an alignment film that has been subjected to an alignment treatment. Is destroyed to cause poor alignment such as pressure defects, or lowers the alignment regulating force of the alignment film on the interface between the counter substrate and the ferroelectric liquid crystal to the ferroelectric liquid crystal. Sometimes.
[0006]
In addition, when the pressure is reduced so as not to cause the above-described alignment failure, the sealing inlet cannot be sufficiently filled with the sealing agent, so that liquid crystal leakage or impurity penetration occurs under an environmental test or the like. There was a problem. Further, the liquid crystal adheres to the sealing portion near the liquid crystal injection port, which may cause poor sealing, and a step of removing the liquid crystal in the sealing portion is required. Since the ferroelectric liquid crystal has a high viscosity at room temperature, it has low fluidity, and since the distance between the substrates is as small as 2 μm or less, it is difficult to remove excess liquid crystal.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and pressurize a ferroelectric liquid crystal display element in a process before sealing after injecting a ferroelectric liquid crystal into a ferroelectric liquid crystal display element using a ferroelectric liquid crystal. It is an object of the present invention to provide a method of manufacturing a ferroelectric liquid crystal display element which allows a sealing portion to be filled with a sealing agent without any problem.
[0008]
[Means for Solving the Problems]
The transparent substrate having the display electrode and the silicon backplane are opposed and integrated with a predetermined gap via an adhesive formed so as to surround the display portion, and the transparent substrate, the silicon backplane, and the adhesive A ferroelectric liquid crystal is injected from an injection port into the ultra-thin space formed by the step (a), an extra ferroelectric liquid crystal near the injection port is removed, and then the injection port is sealed. Before the sealing, at least the sealing portion (near the inlet of the ferroelectric liquid crystal inlet) of the ferroelectric liquid crystal display element was immersed in a solvent to remove the ferroelectric liquid crystal at the inlet of the ferroelectric liquid crystal, thereby removing the ferroelectric liquid crystal. A method for manufacturing a ferroelectric liquid crystal display element in which a portion is filled with a sealing agent and then cured.
[0009]
A pair of transparent substrates having display electrodes on the surfaces facing each other are opposed and integrated with a predetermined gap via an adhesive formed so as to surround the display portion, and the pair of transparent substrates and the adhesive A ferroelectric liquid crystal is injected from an injection port into the ultra-thin space formed by the step (a), an extra ferroelectric liquid crystal near the injection port is removed, and then the injection port is sealed. Before the sealing, at least the sealing portion (near the inlet of the ferroelectric liquid crystal inlet) of the ferroelectric liquid crystal display element was immersed in a solvent to remove the ferroelectric liquid crystal at the inlet of the ferroelectric liquid crystal, thereby removing the ferroelectric liquid crystal. A method for manufacturing a ferroelectric liquid crystal display element in which a portion is filled with a sealing agent and then cured.
[0010]
Further, as in the third aspect of the present invention, a manufacturing method in which ultrasonic waves are used when immersed in the solvent is used. In the description of the present invention, the liquid crystal is described as a ferroelectric liquid crystal, but it can be easily applied to the manufacture of a liquid crystal display device using another liquid crystal.
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0011]
FIGS. 1A and 1B illustrate an embodiment of a method of manufacturing a ferroelectric liquid crystal display device according to the present invention, in which FIG. 1A is a schematic view near an injection port after injection of a ferroelectric liquid crystal, and FIG. (B) is a top view and a side cross-sectional view schematically showing the vicinity of the injection port after removing the ferroelectric liquid crystal, and (c) is a top view and a side cross-sectional view schematically showing the vicinity of the injection port after the sealing agent is cured. In (a) to (c), 1 is a transparent substrate or silicon backplane having display electrodes, 2 is a transparent substrate having display electrodes, and 3 is a transparent substrate and a silicon backplane or a pair of transparent substrates. This is a chemical reaction type adhesive for maintaining and integrating the gap, and forms an injection port 5 for injecting the ferroelectric liquid crystal 4 at the same time as surrounding the display area. Numeral 6 denotes an inlet from which the ferroelectric liquid crystal is removed, and numeral 7 denotes a sealing agent.
[0012]
As shown in FIG. 1A, when the ferroelectric liquid crystal 4 is injected, the ferroelectric liquid crystal 4 is concentrated and accumulated around the injection port 5 due to surface tension. It is necessary to remove the ferroelectric liquid crystal outside the injection port 5 in some state while maintaining the pressurized state.
[0013]
As shown in FIG. 1B, in the present invention, at least the portion of the ferroelectric liquid crystal display element where the ferroelectric liquid crystal is removed (the injection port) is immersed in a solvent at the inlet of the injection port 5. By forming the inlet 6, as shown in FIG. 1C, it becomes possible to fill the chemically reactive adhesive 7 as a sealing agent by utilizing a capillary phenomenon.
[0014]
Here, the solvent used in the present invention is capable of dissolving the ferroelectric liquid crystal and does not affect the orientation of the inlet of the injection port, and may be any solvent suitable for the characteristics of the ferroelectric liquid crystal to be injected. It can be appropriately selected depending on the dielectric liquid crystal.
[0015]
FIG. 2 is a comparison of the initial state of the sealing portion of the ferroelectric liquid crystal display element, the state of immersion in a solvent for a predetermined time, and the state of removal of ferroelectric liquid crystal accumulated around the injection port when ultrasonic waves are used in combination. FIG. Experiments show that by appropriately selecting the immersion time, the ferroelectric liquid crystal adhering to the sealing portion and the ferroelectric liquid crystal at the inlet of the injection port can be removed.
[0016]
Furthermore, as shown in FIG. 2, when ultrasonic waves are used in combination, the dissolution time of the ferroelectric liquid crystal can be shortened as compared with the method using only immersion, and it can be said that there is a great effect in manufacturing. .
[0017]
Here, the frequency and intensity of the ultrasonic wave used in the present invention are not particularly limited as long as the frequency and intensity promote the dissolution rate of the ferroelectric liquid crystal and do not adversely affect the ferroelectric liquid crystal display element. .
【The invention's effect】
As described above, in the method for manufacturing a ferroelectric liquid crystal display device according to the first and second aspects of the present invention, a sealing agent is filled into a sealing inlet without applying pressure in a process before sealing a ferroelectric liquid crystal display device. Therefore, the layer structure at the time of ferroelectric liquid crystal alignment is not destroyed, and it is possible to prevent poor alignment such as pressure defects. Furthermore, it is possible to prevent the alignment film having been subjected to the alignment treatment at the interface between the counter substrate and the ferroelectric liquid crystal from affecting the alignment regulating force on the ferroelectric liquid crystal. Since the sealing portion can be cleaned, the reliability of the sealing can be improved, and leakage of ferroelectric liquid crystal and impurity penetration under an environmental test or the like can be prevented.
[0018]
The method for manufacturing a ferroelectric liquid crystal display element according to the invention according to claim 3 is characterized in that the ferroelectric liquid crystal display element is immersed in a solvent to remove the ferroelectric liquid crystal, and at the same time, an ultrasonic wave is used together. The removal of the ferroelectric liquid crystal can be performed efficiently and in a short time.
[Brief description of the drawings]
FIGS. 1A and 1B are views for explaining an embodiment of the present invention, in which FIG. 1A is a schematic top view and a side cross-sectional view of the vicinity of an injection port after injection of a ferroelectric liquid crystal, and FIG. FIG. 2C is a schematic top view and a side cross-sectional view of the vicinity of the injection port after the injection, and FIG. 2C is a schematic top view and a side cross-sectional view of the vicinity of the injection port after the sealing agent is cured. A graph showing a comparison between the state, the state of immersion in a solvent for a predetermined time, and the state of removal of ferroelectric liquid crystal accumulated around the injection port when ultrasonic waves are used together.
REFERENCE SIGNS LIST 1 Transparent substrate or silicon backplane with display electrode 2 Transparent substrate with display electrode 3 Chemical reaction type adhesive 4 Ferroelectric liquid crystal 5 Injection port 6 Injection port from which ferroelectric liquid crystal is removed 7 Sealant

Claims (3)

The transparent substrate having the display electrode and the silicon backplane are opposed and integrated with a predetermined gap via an adhesive formed so as to surround the display portion, and the transparent substrate, the silicon backplane, and the adhesive A ferroelectric liquid crystal is injected from an injection port into the ultra-thin space formed by the step (a), an extra ferroelectric liquid crystal near the injection port is removed, and then the injection port is sealed. Before the sealing, at least the sealing portion (near the inlet of the ferroelectric liquid crystal inlet) of the ferroelectric liquid crystal display element was immersed in a solvent to remove the ferroelectric liquid crystal at the inlet of the ferroelectric liquid crystal, thereby removing the ferroelectric liquid crystal. A method for producing a ferroelectric liquid crystal display element, comprising curing a part after filling the part with a sealing agent. A pair of transparent substrates having display electrodes on the surfaces facing each other are opposed and integrated with a predetermined gap via an adhesive formed so as to surround the display portion, and the pair of transparent substrates and the adhesive are Ferroelectric liquid crystal is injected from an injection port into an ultra-thin space formed by the method, and after removing excess ferroelectric liquid crystal in the vicinity of the injection port, the ferroelectric liquid crystal display element is sealed. By immersing at least the sealing portion of the ferroelectric liquid crystal display element (near the inlet of the ferroelectric liquid crystal inlet) in a solvent before the sealing, the ferroelectric liquid crystal at the inlet of the inlet is removed, and the ferroelectric liquid crystal is removed. A method for producing a ferroelectric liquid crystal display device, comprising: filling a sealing material into a sealing material; 3. The method for manufacturing a ferroelectric liquid crystal display device according to claim 1, wherein ultrasonic waves are used together when the ferroelectric liquid crystal is removed by immersion in the solvent.

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