JPH08171093A - Production of liquid crystal display device and its device - Google Patents

Abstract

PURPOSE: To decrease and simplify stages by making it possible to inject liquid crystals in the stage of sticking substrates on premises that the liquid crystals and oriented films are not photodeteriorated. CONSTITUTION: This process consists of a pattern forming stage for forming display patterns P on the respective inner sides of substrates 2, 3, a sealing stage for forming a sealing member 6 by a photosetting resin enclosing the display patterns P of the substrate 2 and its peripheral parts and a spacer forming stage for likewise arranging spacers 7 within the display patterns P of the substrate 2. Further, the process consists of a liquid crystal injecting stage for injecting the liquid crystals 8 to the substrate 2 formed with the sealing member 6, a gap adjusting stage for sticking another substrate 3 to the substrate 2 injected with the liquid crystals 8 and pressurizing both substrates 2, 3 via the spacers 7 until a prescribed gap is attained between both substrates and a sealing curing stage for curing the sealing member 6 by irradiating the sealing member with UV light. The upper surface plate disposed at the device allows the transmission of the UV light.

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 display device and the device thereof.

[0002]

2. Description of the Related Art Conventionally, in a manufacturing process of a liquid crystal display device, a process of bonding two transparent substrates such as glass and resin with a gap for injecting the liquid crystal generally means that the liquid crystal is injected at this stage. Instead, he just assembles empty cells. In the empty cell, two substrates, a front surface and a back surface, are aligned with each other, and a sealing member is interposed between the bonded substrates to form a liquid crystal injection gap. Since thermosetting resin has been mainly used for the sealing member, when liquid crystal is sealed during bonding, when the sealing resin is baked and cured, the resin solvent is vaporized and mixed with the liquid crystal at a high heat treatment temperature. Therefore, there is a problem that the liquid crystal is deteriorated. Therefore, it takes time and effort to inject the liquid crystal after assembling the empty cell. In view of these circumstances, a photo-curable resin that does not require high-temperature heat treatment, such as a thermosetting resin, can be used as the sealing material. This photocurable resin does not need to be heated and can be cured by UV (ultraviolet light) irradiation. Therefore, the liquid crystal injection step can be incorporated into the step of bonding the two substrates, which has the advantage of shortening and simplifying the step.

[0003]

However, the problem here is that a considerably strong UV irradiation is required to cure the sealing member made of the photocurable resin. As a result, new fears such as deterioration of the alignment film and liquid crystal molecules formed on the substrate due to the strong UV irradiation are raised. From the above circumstances, it is ideal that the seal member is made of a photo-curable resin and is irradiated with UV so that the liquid crystal can be sealed at the cell assembly stage by bonding the substrates. At the time of UV irradiation, it is necessary to mask other panel components such as the liquid crystal and the alignment film to shield the light. An object of the present invention is to provide a method of manufacturing a liquid crystal display device and a device thereof, which enables liquid crystal to be encapsulated at the stage of substrate bonding without photo-deteriorating the liquid crystal or the alignment film, thereby reducing the manufacturing process and simplifying the manufacturing process. To provide.

[0004]

In order to achieve the above object, a method of manufacturing a liquid crystal display device according to the present invention comprises a pattern forming step of forming a display pattern composed of transparent electrodes or the like on each of two substrates. A seal forming step of forming a seal member made of a photocurable resin in a shape surrounding at least the display pattern of one substrate, and surrounded by the seal member on one substrate after the seal forming step in a degassed environment A liquid crystal injecting step of injecting liquid crystal into the region, a step of adhering the other substrate to the one substrate in which the liquid crystal is infused, a gap adjusting step of pressurizing until the two substrates have a predetermined gap, and the adhering step. A seal curing step of selectively irradiating only the seal member with light and curing the seal while the two substrates are held in the predetermined gap.
Further, in the manufacturing method of the present invention, the light-shielding film can be coated on the display pattern region except the region corresponding to the seal member before irradiation with light and peeled off after irradiation with light.
The manufacturing apparatus of the present invention is capable of pressurizing two substrates, a lower surface plate on which a liquid crystal display panel is set and a liquid crystal display panel set on the lower surface plate, and an upper surface plate capable of transmitting light. And a light source for irradiating light to a seal member made of a photo-curable resin provided on the liquid crystal display panel through the upper platen. In addition, in this manufacturing apparatus, a mask-patterned light-shielding film that irradiates light only to the sealing member is pressure-bonded to an appropriate position on the upper surface of the substrate facing the light source, and the light-shielding film is peeled off after light irradiation. It is possible to have a device. Furthermore, in this manufacturing apparatus, the upper platen can be formed in the shape of an elastic bag that is expandable and contractible by gas injection.

[0005]

In this method of manufacturing a liquid crystal display device, a seal member made of a photocurable resin is formed on one of the two substrates, and the liquid crystal is injected into the substrate after the seal forming step in a deaerated environment. The other substrate is attached to the liquid crystal-filled substrate, and the gap is adjusted by pressing through the spacer until a predetermined gap is created between the two substrates.Under this condition, only the sealing member is irradiated with ultraviolet light and cured. Let Therefore, the liquid crystal can be injected at the stage of bonding the substrates without causing the liquid crystal and the alignment film to be deteriorated by light, and the steps can be reduced and simplified. Further, in this manufacturing method, the display pattern excluding the seal member is covered with a light shielding film before irradiation with light,
By selectively irradiating only the seal member with light, the liquid crystal and the alignment film in the display pattern can be reliably prevented from being deteriorated by light. On the other hand, in the manufacturing apparatus of the present invention, since the upper platen is formed of a material that allows light to be transmitted in addition to the pressure function, it can be cured as a material for the sealing member of the liquid crystal display panel set below. There is an advantage that a photocurable resin that does not require heating and is cured by light can be used. Further, in this manufacturing apparatus, since the light shielding film is pressure-bonded to the upper surface of the substrate facing the light source, and the light shielding film is peeled off after the light irradiation, efficient mass production becomes possible.
Furthermore, if the upper surface plate is formed into an elastic bag shape that allows ultraviolet light to pass therethrough and is expandable and contractible by gas injection, the temperature rise of the substrate due to light irradiation can be suppressed by adjusting the temperature of the filling air. The substrate can be pressed uniformly and uniformly by the fluid press.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a liquid crystal display device according to the present invention and an embodiment of the device will be described below with reference to the drawings. The outline of the manufacturing process of the liquid crystal display panel 1 shown in FIG. 1 is that a transparent electrode 4 is provided inside each of two substrates 2 and 3.
And a pattern forming step of forming a display pattern composed of the alignment film 5 and the like, and a seal forming step of forming a seal member 6 made of a photo-curable resin so as to surround the display pattern of one substrate 2 and a peripheral portion of the substrate in the embodiment Further, in the embodiment, similarly, a spacer forming step of arranging the spacer 7 in the display pattern of the substrate 2, a liquid crystal injecting step of dropping the liquid crystal 8 in an area surrounded by the seal member 6 of the substrate 2, and a liquid crystal 8 being infused. The other substrate 3 is attached to the other substrate 2, and a gap adjusting step is performed to press the two substrates 2 and 3 through a spacer 7 until a predetermined gap is obtained, and a seal member 6 is irradiated with ultraviolet light and cured. It consists of a curing process.

First, in the pattern forming step, a transparent electrode 4 made of an ITO film is formed as a conductive film inside each of two transparent substrates 2 and 3 made of glass or the like so as to cover the transparent electrode 4. The display pattern is formed by forming the alignment film 5 as described above. For the alignment film 5, a photo-curable polyimide resin having an excellent function as a liquid crystal molecule parallel alignment treatment agent can be used.

In the next seal forming step, as shown in FIG. 2, a seal member 6 made of a photocurable resin is formed on the lower substrate 2 so as to surround the display pattern P formed in the previous step. Not only the display pattern P but also the substrate 2
In order to reduce the effect of changes in external pressure on the entire area around,
The seal member 6 is formed. The seal member 6 is obtained by applying a predetermined pattern by screen printing or a dispenser.

In the spacer forming step, the spacers 7 are similarly provided on the lower substrate 2 in a scattered manner. As the spacer 7, the liquid crystal 8 does not overlap each other.
With the advantage that it is easy to secure the layer thickness (gap) of the layer uniformly, for example, with the granular spacer used in this embodiment,
A silica glass type or a resin type is suitable.

The two substrates 2 and 3 are prepared by the above-mentioned forming steps and sent to the next liquid crystal injecting step. In a sufficiently degassed vacuum atmosphere, liquid crystal is dropped and injected into the display pattern P surrounded by the seal member 6 on the lower substrate 2. Next, the prepared upper substrate 3 is superposed on the lower substrate 2 into which the liquid crystal is injected.

With respect to the superposed substrates 2 and 3, the spacer 7 is formed until a predetermined gap is formed between the two substrates 2 and 3.
Then, a gap adjusting step of applying pressure through However, before the gap adjusting step, the film 9 of the light shielding member according to the present invention is attached to the upper surface of the upper substrate 3 to prepare for the gap adjusting step by pressurization and the seal hardening step of the next step. If this light-shielding film attaching step is performed in a vacuum atmosphere after liquid crystal injection before adjusting the gap, it is possible to save the trouble of preparing a vacuum atmosphere for the light-shielding film attaching step.

The light-shielding film 9 is irradiated with the ultraviolet light 12 from the UV (ultraviolet light) lamp described in the seal curing step only through the mask pattern hole 9a to the sealing material 6, and the display pattern P (transparent electrode 4, Alignment film 5 and liquid crystal 8
And the like) is formed by masking the panel structure portion (for example, etc.) so as to shield light. The light-shielding film 9 is a long one wound in a roll shape, and the length corresponding to one liquid crystal display panel 1 is the UV irradiation device shown in FIG. 3 by the film supply device 20 shown in FIG. 10 is a member that is supplied to the substrate 10 and is peeled off from the upper surface of the substrate 3 after UV irradiation.

In the gap adjusting process and the seal curing process, the UV irradiation device 10 and the film supply device 20 are used.
Thus, the seal member 6 is cured while adjusting the gap. First, the configuration of both devices 10 and 20 is the UV irradiation device 1
Reference numeral 0 has a lamp 11 as a light source for irradiating the ultraviolet light 12, below which an upper surface plate 13 capable of transmitting the ultraviolet light 12 is arranged, and below this, a lower surface plate 14 is arranged.
The liquid crystal display panel 1 to be manufactured is set between the upper and lower surface plates 13 and 14. The upper platen 13 is made of, for example, quartz glass for transmitting the ultraviolet light 12. Further, the film supply device 20 is UV
In the front-back direction of the assembly line before and after the irradiation device 10, the light-shielding film 9 is provided on the upper substrate 3 of the liquid crystal display panel 1.
A pair of a drum 21 and a sticking roller 22 which are supplied to the upper side substrate 3 and a pair of a roller 23 and a winding drum 24 for peeling the used light-shielding film 9 from the upper substrate 3 are arranged.

In FIG. 4, when the semi-finished panel substrates 2 and 3 are conveyed after the liquid crystal injecting step is completed, the light is shielded from the supply drum 21 of the film supply device 20 by the length of one panel. The film 9 is fed out, and the light-shielding film 6 is pressure-bonded and bonded to the upper surface of the upper substrate 3 by the bonding roller 22. When pressing this film,
It is performed in a vacuum environment so that air bubbles do not enter between the light-shielding film 9 and the upper substrate 3.

The panel semi-finished product to which the light-shielding film 9 has been pressure-bonded is taken out under atmospheric pressure and sent to the UV irradiation device 10 in FIG. 3, where it enters the gap adjusting step as the first step. When the substrates 2 and 3 of the panel semi-finished product are taken out under the atmospheric pressure, a force for pressing the substrates 2 and 3 from the outside acts due to the difference in the internal and external atmospheric pressures between the substrates and 3 which are evacuated when the liquid crystal is injected. Further, for example, when the upper surface plate 13 is lowered, the semi-finished panel product is sandwiched between the lower surface plate 14 and the lower surface plate 14 via the air layer and pressed from above and below, so that a predetermined gap is formed between the two substrates 2 and 3. Is pressurized via the spacer 7.

With the gap between the two substrates 2 and 3 adjusted to a predetermined value, the semi-finished panel product is irradiated with ultraviolet light 12 from the upper UV lamp 11 to start the seal curing step. The ultraviolet light 12 passes through the upper surface plate 13, shields the display pattern P according to the mask pattern of the lower light shielding film 9, and irradiates only the sealing member 6 arranged on the lower substrate 2. This is cured.

In FIG. 4, the semi-finished product of the liquid crystal display panel 1 in which the sealing member 6 is cured by the irradiation of the ultraviolet light 12 and both substrates 2 and 3 are fixed is sent to the peeling roller 23 of the film supply device 20, Here, the light-shielding film 9 that has been used is peeled off, and the peeled-off light-shielding film 9 is taken up by the winding roller 2
Let it roll up to 4.

On the other hand, FIG. 5 shows another embodiment of the UV irradiation device 10 in the above embodiment. according to it,
In the UV irradiation device 10 of FIG. 3, the ultraviolet light 12 is irradiated under atmospheric pressure after the light-shielding film 9 is attached, but the upper platen 15 formed in the shape of a rubber bag capable of transmitting ultraviolet light is used.
It is used for pressure-bonding the light-shielding film 9. That is, by sending compressed air from the pressure valve 16 to the bag-shaped upper surface plate 15, the light shielding film 9 is pressed against the upper substrate 3 by the expansion of the upper surface plate 15. By this action, if the temperature of the compressed air is adjusted, the temperature rise of the substrates 2 and 3 due to the irradiation of ultraviolet light from the UV lamp 11 can be suppressed.

The upper platen 15 of the compressed air system shown in FIG.
According to the above, while the solid fixed upper surface plate 13 of FIG. 3 needs to strictly maintain the parallelism and the levelness with the lower surface plate 14, the two substrates 2 with a fluid such as air, Even if dust or the like intervenes with respect to No. 3, it is possible to uniformly pressurize, and if the temperature of the compressed air is adjusted as described above, the temperature rise of the substrates 2 and 3 due to the influence of ultraviolet light irradiation can be suppressed. There is.

[0020]

As described above, in the method for manufacturing a liquid crystal display device according to the present invention, a thermosetting resin which has been conventionally used for a seal member and which requires high temperature heat treatment is used.
Since a light-curable resin that is cured by light is used to irradiate light only on the sealing member with a light-shielding film, the risk of photo-degrading the liquid crystal and the alignment film is eliminated, and the liquid crystal at the stage of substrate bonding is eliminated. It is effective because it enables injection, can significantly reduce the number of steps compared to the conventional steps, and can simplify the process. Further, the manufacturing apparatus of the present invention enables the use of the photocurable resin as the sealing member by molding the upper platen with a material capable of transmitting ultraviolet light in addition to the pressure function, and the above manufacturing method is effective. There is an advantage that can be done.

[Brief description of drawings]

FIG. 1 is a side sectional view of a main part of a liquid crystal display panel manufactured by a method for manufacturing a liquid crystal display device according to the present invention.

FIG. 2 is a plan view of a liquid crystal display panel of an embodiment of the present invention, which is sealed with a sealing member.

FIG. 3 is an overall side sectional view of a UV irradiation device included in the liquid crystal display manufacturing apparatus according to the present invention.

FIG. 4 is an overall side sectional view of a film supply device that constitutes the manufacturing apparatus of the present invention together with the UV irradiation device.

FIG. 5 is a side cross-sectional view of a configuration in which an upper surface plate is a pressurized air filling system as another embodiment of the UV irradiation device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display panel 2, 3 Substrate 4 Transparent electrode 5 Alignment film 6 Sealing member 7 Spacer 8 Liquid crystal 9 Light-shielding film 10 UV irradiation device 13, 15 Upper surface plate 14 Lower surface plate 20 Film supply device 22 Adhering roller 23 Peeling roller

Claims (5)

[Claims] 1. A pattern forming step of forming a display pattern composed of a transparent electrode or the like on each of two substrates, and a seal for forming a sealing member made of a photocurable resin in a shape surrounding at least the display pattern of one substrate. Forming step, a liquid crystal injecting step of injecting liquid crystal into a region surrounded by the seal member on one substrate after the seal forming step in a degassed environment, and A step of bonding the substrates, a step of adjusting the gap to pressurize the two substrates until a predetermined gap is formed, and a state in which the two bonded substrates are held in the predetermined gap, and only the sealing member is provided. A method of manufacturing a liquid crystal display device, comprising: a seal curing step of selectively irradiating light to cure. 2. The method for manufacturing a liquid crystal display device according to claim 1, wherein the display pattern region except the region corresponding to the seal member is covered with the light-shielding film before light irradiation, and peeled off after light irradiation. 3. A lower surface plate on which a liquid crystal display panel is set, and an upper surface plate which is operable to pressurize two substrates of the liquid crystal display panel set on the lower surface plate and is capable of transmitting light. An apparatus for manufacturing a liquid crystal display device, comprising: a light source that irradiates a sealing member made of a photocurable resin provided on a liquid crystal display panel with light through an upper surface plate. 4. A film attaching / detaching device for pressing a light-shielding film, which is mask-patterned so that only a sealing member is irradiated with light, at an appropriate position on the upper surface of a substrate facing a light source, and peeling the light-shielding film after light irradiation. The apparatus for manufacturing a liquid crystal display device according to claim 3, further comprising: 5. The apparatus for manufacturing a liquid crystal display device according to claim 3, wherein the upper surface plate is formed in an elastic bag shape that is expandable and contractible by gas injection.