JPH07168192A - Formation of liquid crystal cell - Google Patents

Abstract

PURPOSE:To provide a liquid crystal cell free from the disturbance of vertical orientation even in working at a high temp. CONSTITUTION:Glass substrates 1, 2 on which vertical oriented films 5, 6 are formed are placed so that the vertical oriented films 5, 6 are opposite to each other and a sealing part 7 formed between peripheral parts and made of an ultraviolet curing resin is heated at 100 deg.C for 10 hours after completely hardened by the irradiation with ultraviolet ray. As a result, since volatile matters are removed from the sealing part 7, various optical elements having high reliability are provided without attacking the vertically oriented films 5, 6 even when the an optical member using the liquid crystal cell is worked at a high temp.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid crystal cell used as a constituent member of a spatial light modulator used as a constituent element in a display device, an image pickup device, an optical computer or the like and an optical element such as a liquid crystal panel. Regarding

[0002]

2. Description of the Related Art In order to obtain image information with high definition in various devices such as a display device and an image pickup device, an optical element used as a constituent element of the above various devices, Although a device capable of obtaining high-resolution image information is required, a spatial light modulator has been attracting attention as one of optical elements capable of obtaining high-resolution image information. The spatial light modulator is constructed by laminating a transparent substrate on which a transparent electrode is attached, a photoconductive layer member, a dielectric mirror, a light modulator material layer member and a transparent substrate on which a transparent electrode is attached. A spatial light modulator having a configuration mode using a liquid crystal cell as a light modulator layer member is also known.
It is also well known that the liquid crystal cell is widely used as a component of a transmissive liquid crystal display panel known as a kind of light valve and other optical elements.

By the way, the portion of the liquid crystal cell in the optical element using the liquid crystal cell as one of the constituent members is constructed as having a liquid crystal layer having an extremely thin constant thickness. The configuration is such that a liquid crystal layer having an extremely thin constant thickness is laterally surrounded by a seal portion. Then, conventionally, the seal portion in the liquid crystal cell is used as the seal material while using, for example, a thermosetting resin as the seal material and being pressed so that the thickness of the seal portion becomes a predetermined thickness. Although heating was performed for a long time until the thermosetting resin was completely cured, when the thermosetting resin was used as the sealing material as described above, a pressure device was used when manufacturing the liquid crystal cell. As a result, various problems such as the need for a heat resistant structure, the use of a large heating device, the change in pressure due to heating, and the loss of uniformity in cell thickness are caused. It had the drawback of low productivity.

In order to solve the above problems, for example, as disclosed in Japanese Patent Laid-Open No. 54-73063,
Proposals have been made to use an ultraviolet curable resin as a sealing material for the seal part of a liquid crystal cell, but if the ultraviolet curable resin used as a sealing material is not sufficiently cured, uncured components may be contained in the liquid crystal layer. The problem is that it melts out and impairs the liquid crystal alignment. As a solution to the problem, for example, as disclosed in JP-A-4-107530, an ultraviolet curable resin used as a sealing material is irradiated with ultraviolet rays. Proposals have also been made for glass substrate structures in order to be able to fully carry out.

[0005]

By the way, if the UV-curable resin used as the sealing material is sufficiently cured in the seal portion of the liquid crystal cell, the uncured component may be contained in the liquid crystal layer. It should not melt out and impair the alignment of the liquid crystal, but even if the seal portion of the liquid crystal cell is in a state where the ultraviolet curable resin used as the sealant is sufficiently cured, As the temperature rises, volatile components contained in the ultraviolet curable resin are likely to be generated, and the volatile components attack the organic vertical alignment film in the liquid crystal cell and disturb the alignment of the liquid crystal. When the optical element using the liquid crystal cell is, for example, an optical element for displaying a high-luminance display image on the screen, strong light is incident on the liquid crystal cell during the display operation. In addition, the temperature of the liquid crystal cell rises, and the liquid crystal cell used in the on-vehicle display device may be exposed to a temperature change from a temperature below the freezing point to a temperature of 80 degrees Celsius or more. In particular, the advent of a liquid crystal cell that can maintain high reliability even when the liquid crystal cell operates at a high temperature has been desired.

[0006]

According to the present invention, two members, each having a vertical alignment film formed thereon, are arranged in parallel so that the vertical alignment films face each other, and the two members described above are provided. A method of manufacturing a liquid crystal cell in which a seal portion is formed of an ultraviolet curable resin between peripheral portions of the above, and a vertical alignment type liquid crystal is filled in a space surrounded by the two members and the seal portion and sealed. , A method of manufacturing a liquid crystal cell, which comprises a step of performing a heat treatment after curing a seal portion made of an ultraviolet curable resin formed between the peripheral portions of the above-mentioned two members by irradiation of ultraviolet rays, and a vertical method The two members on which the alignment film is formed are arranged in parallel so that the vertical alignment films face each other, and the ultraviolet curable resin is provided between the peripheral portions of the two members. A method of manufacturing a liquid crystal cell in which a vertical alignment type liquid crystal is filled in a space surrounded by the two members and a seal part and sealed, which is a peripheral part of the two members. The UV-curable resin seal portion formed in between is cured by irradiation with ultraviolet rays, and then heated at 100 degrees Celsius for 10 hours, and thereafter,
Provided is a method of manufacturing a liquid crystal cell in which a vertically aligned liquid crystal is filled and sealed in a space surrounded by the two members and a sealing part after cooling to room temperature.

[0007]

[Function] The seal portion made of the ultraviolet curable resin formed between the peripheral portions of the two members each having the vertical alignment film formed thereon is cured by irradiation with ultraviolet rays, and then the temperature is adjusted to 1 degree Celsius.
By heating at 00 degrees for 10 hours, the volatile components are removed from the seal portion made of the ultraviolet curable resin that is completely cured by the irradiation of ultraviolet rays, so that the optical member using the liquid crystal cell is The vertical alignment film is not damaged even when it is operated at a high temperature, and various highly reliable optical elements can be provided.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The concrete contents of the method for manufacturing a liquid crystal cell of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a vertical sectional side view of a liquid crystal cell manufactured by applying the liquid crystal cell manufacturing method of the present invention, and FIG. 2 is a plan view of a seal portion. In the liquid crystal cell shown in FIG. 1, 1 and 2 are glass substrates, 3 and 4 are transparent electrodes, 5 and 6 are vertical alignment films, 7 is a sealing portion made of an ultraviolet curable resin, 8 is glass beads used as spacers, and 9 is a spacer. Is a sealing material. A transparent electrode 3 is formed on the glass substrate 1 by depositing a thin film of indium oxide (In2O3) by a vacuum deposition method, and a thin electrode of indium oxide is deposited on the glass substrate 2 by a vacuum deposition method. 4 are formed. As described above, a thin film of silicon dioxide (SiO2) having a film thickness of 800 angstroms is obliquely formed on the transparent electrodes 3 and 4 surfaces of the glass substrates 1 and 2 on which the transparent electrodes 3 and 4 are formed at an incident angle of 70 degrees. The vertical alignment films 5 and 6 are formed by adhering octadecanol molecules on the above-mentioned silicon dioxide film by allowing it to stand in an octadecanol vapor atmosphere for 2 hours after the vapor deposition method is applied to deposit them. Let

As described above, one of the two glass substrates 1 and 2 having the vertical alignment film formed on the transparent electrode, for example, the surface of the glass substrate 1 on which the vertical alignment film 5 is formed. Around the circumference of a certain diameter (eg 3μ
An ultraviolet curable resin containing only 1.5% by weight of glass beads (diameter of m) is applied in a predetermined pattern necessary for forming the seal portion 7 by, for example, a screen printing method. In addition, in the coating pattern of the ultraviolet curable resin, in order to fill the vertical alignment type liquid crystal in the space surrounded by the two glass substrates 1 and 2 functioning as two members and the seal portion 7. It goes without saying that the liquid crystal inlet 7a necessary for the above should be provided. As the above-mentioned UV-curable resin, for example, any of polyester acrylate-based UV-curable resin, epoxy-based UV-curable resin, and urethane acrylate-based UV-curable resin can be favorably used. In addition, the entire surface of the other glass substrate of the two glass substrates 1 and 2 having the vertical alignment film formed on the transparent electrode, for example, the surface of the glass substrate 2 on which the vertical alignment film 6 is formed, Glass beads having a predetermined diameter (for example, a diameter of 3 μm) are uniformly dispersed. The glass beads described above are for defining the thickness of the liquid crystal layer.

Next, the two glass substrates 1 and 2 described above are used.
Are correctly laminated in a state where the vertical alignment films 5 and 6 respectively formed face each other, and then, for example, by an air bag, pressure is applied at a pressure of 0.3 kg per square centimeter, and in that state, ultraviolet rays (wavelength of 350 nm to Four
00 nm). When the intensity of the ultraviolet rays was 100 mw per square centimeter, the ultraviolet curable resin was completely cured by irradiation for 2 to 3 minutes. After the ultraviolet curable resin is completely cured to form the seal portion 7 made of the ultraviolet curable resin, the airbag is removed, and the two sheets are adhered by the seal portion 7 as described above. The glass substrate of (1) is placed in an oven whose internal temperature is maintained at 100 degrees Celsius for 10 hours or more to be heated. At this time, it is effective to reduce the pressure in the oven by using a rotary pump or the like.

After a lapse of a predetermined time, it is taken out of the oven and left in the atmosphere, and when the temperature of the two glass substrates adhered by the seal portion 7 is lowered to room temperature, a cyanobiphenyl type vertically aligned liquid crystal (for example, , MLC2010 manufactured by Merck & Co., Inc. is injected through the liquid crystal injection port 7a provided in the seal portion 7, and the injection port 7a is sealed by the sealing material 9. The above-described liquid crystal injection operation is easily performed by supplying a predetermined amount of liquid crystal to the liquid crystal injection port 7a in a vacuum atmosphere and then taking it out to the atmospheric pressure. Further, as the sealing material 9 for sealing the injection port 7a described above, an appropriate adhesive can be used. The liquid crystal cell manufactured as described above has excellent heat resistance,
Even when the accelerated test of leaving the liquid crystal cell in a constant temperature chamber at 100 degrees Celsius was performed, no deterioration in the initial characteristics was observed.

[0012]

As is clear from the above description, the method for manufacturing a liquid crystal cell of the present invention is such that two members each having a vertical alignment film face each other. And are positioned in parallel with each other, and a seal portion is formed between the peripheral portions of the two members by an ultraviolet curable resin, and a vertical alignment type is provided in a space portion surrounded by the two members and the seal portion. When a liquid crystal cell is manufactured by filling and sealing with liquid crystal, a seal portion made of an ultraviolet curable resin formed between the peripheral portions of two members each having a vertical alignment film formed thereon is irradiated with ultraviolet rays. After curing, by heating at 100 degrees Celsius for 10 hours, the volatile components are removed from the seal portion made of the ultraviolet curable resin that is completely cured by the irradiation of ultraviolet rays. Therefore, even if an optical member using a liquid crystal cell is operated at a high temperature, the vertical alignment film is not damaged and various highly reliable optical elements can be provided. In the method, the device used when manufacturing the liquid crystal cell may be small in size, and the present invention can satisfactorily solve the above-mentioned conventional problems.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view of a liquid crystal cell manufactured by applying a liquid crystal cell manufacturing method of the present invention.

FIG. 2 is a plan view of a seal portion.

[Explanation of symbols]

1, 2 ... Glass substrate, 3, 4 ... Transparent electrode, 5, 6 ... Vertical alignment film, 7 ... Sealing part by UV curable resin, 8 ... Glass beads used as spacers, 9 ... Sealing material,

Claims (2)

[Claims] 1. A vertical alignment film is formed on each of the two.
Two members are positioned in parallel so that the vertical alignment films face each other, and a seal portion is formed between the peripheral portions of the two members by an ultraviolet curable resin. A method of manufacturing a liquid crystal cell in which a space surrounded by a seal part is filled with vertical alignment type liquid crystal and hermetically sealed, wherein a seal part formed of an ultraviolet curable resin is formed between the peripheral parts of the two members. , A method of manufacturing a liquid crystal cell, which comprises a step of performing heat treatment after being cured by irradiation of ultraviolet rays. 2. A vertical alignment film is formed on each of the two.
Two members are positioned in parallel so that the vertical alignment films face each other, and a seal portion is formed between the peripheral portions of the two members by an ultraviolet curable resin. A method of manufacturing a liquid crystal cell in which a space surrounded by a seal part is filled with vertical alignment type liquid crystal and hermetically sealed, wherein a seal part formed of an ultraviolet curable resin is formed between the peripheral parts of the two members. After being cured by irradiation with ultraviolet rays, it is heated at 100 degrees Celsius for 10 hours, then cooled to room temperature, and then vertically aligned in the space surrounded by the two members and the seal. A manufacturing method of a liquid crystal cell in which liquid crystal is filled and sealed.