JPH0869002A - Device for determining gap of press-contact assembly and production of liquid crystal display element - Google Patents

Abstract

PURPOSE: To enhance production efficiency and to reduce a manufacturing cost. CONSTITUTION: This device for determining the gap of a press-contact assembly is constituted by arranging a pair of fixing jigs 15, 16 which are respectively transparent, above and below the presscontact assembly 11 and forming annular projecting line parts 23, 24 on the press-contact assembly 11 side of these individual fixing jig 15, 16. A phase difference film 29 and polarizing plate 30 are disposed on the outer side of the fixing jig 16 and a light source 31 is disposed. Fluid is passed in both pressurizing regions 25, 26 enclosed by a pair of the fixing jigs 15, 16, the press-contact assembly 11 and the respective annular projecting line parts 23, 24. The gap between two sheets of the glass substrates is determined by the fluid pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-bonding body gap determining device for adjusting a gap between substrates with higher accuracy for a pressure-bonding body in which two substrates are bonded together, and a liquid crystal display device using the same. The present invention relates to a manufacturing method of.

[0002]

2. Description of the Related Art Recently, a technique for bonding two substrates with high accuracy is required.
The liquid crystal is enclosed between the glass substrates, and the enclosed area is sealed with a sealing material. The gap between these glass substrates is required to be uniform over the substrate surface (hereinafter, The two glass substrates bonded together as described above are called empty cells). Especially in the STN type liquid crystal display device, the display is performed by utilizing the birefringence of the liquid crystal,
Therefore, color unevenness occurs when a uniform gap cannot be obtained over the substrate surface of the empty cell.

Further, the liquid crystal display element is one in which two glass substrates are bonded together via an annular seal portion, and an opening for partially injecting liquid crystal is formed in this annular seal portion, and the liquid crystal is opened from this opening. Was injected. This bonding is performed by a pressure bonding device, but in the liquid crystal display element in which the liquid crystal is injected, the gap between the substrates becomes non-uniform due to mechanical precision and thermal deformation of the two glass substrates when the liquid crystal is injected. .

The applicant of the present invention has been able to solve the above-mentioned problems.
We have proposed a pressure-bonding body gap determining device for determining a gap between substrates with higher accuracy for a pressure-bonding body in which a plurality of substrates are bonded together (see Japanese Patent Application No. 5-35347). This crimping body gap determining device will be described with reference to the schematic diagram shown in FIG.

In the pressure-bonding body gap determining device 1 shown in the figure, a liquid crystal display element cell 3 is arranged between an upper pressure plate 2 and a lower pressure plate 3, and the liquid crystal display element cells 3 of the respective pressure plates 2 and 3 are arranged.
On the side, annular ridges 5 and 6 are formed so as to face the annular seal portion 4 provided in the liquid crystal display element cell 3, and the upper pressing plate 2, the liquid crystal display element 3 and the annular ridge portion are formed. The space area surrounded by the strip portion 5 and the space area surrounded by the lower pressurizing plate 3, the liquid crystal display element 3, and the annular convex strip portion 6 form a pressurizing area 7 and a pressurizing area 8, respectively.

Further, 4 to 6 bolts 9 are provided on the upper pressure plate 2, and a spacer having a predetermined interval is inserted through each bolt 9 in advance. 3 and 3 are brought close to each other, so that both pressurizing plates 2 and 3 can be set at predetermined intervals by the bolt 9.

In order to set the inter-substrate gap of the liquid crystal display element cell 3 by the pressure-bonding body gap determining device 1 described above, it is arranged between the upper and lower pressure plates 2 and 3, bolts 9 are tightened, and air is introduced. A predetermined pressure is applied to both glass substrates of the liquid crystal display element cell 3 by the pressure area 7 and the pressure area 8. Then, the opening of the annular seal portion 4 is closed to seal the liquid crystal.

[0008]

2. Description of the Related Art In the pressure-bonding body gap determining device 1 having the above-described structure, it is not intended to set the inter-substrate gap with higher accuracy for the liquid crystal display element cell 3 in which two substrates are bonded together. However, when the color unevenness of the liquid crystal display element cell 3 is inspected, the liquid crystal display can be obtained only when the opening of the annular seal portion 4 is sealed with an ultraviolet curable resin and then removed from the pressure-bonding body gap determining device 1. The optimum gap control pressure for the element cell 3 could not be found.

Therefore, the liquid crystal display element cell 3 is taken out from the pressure-bonded body gap determining device 1, and then the relationship between the pressure of the compressed air and the color unevenness of the liquid crystal display element cell 3 is found. There is a problem in that the performance of the device 1 cannot be exhibited and immediate determination cannot be performed unless control is tried and the result is determined.

In addition, even if a plurality of pressure conditions are set as described above, there are cases in which there is no optimum condition. In such a case, it is necessary to repeat the work of finding the optimum condition, resulting in manufacturing. There is a problem that the efficiency is lowered and the manufacturing cost is increased.

Therefore, it is an object of the present invention to simply and optimally determine the optimum pressure condition with the crimping body mounted on the crimping body gap determining device, thereby improving the manufacturing efficiency.
Manufacturing costs are to be reduced.

[0012]

According to a first aspect of the present invention, a pressure-bonding body formed by inserting an encapsulating material into a space between two transparent substrates and an annular seal portion between the transparent substrates is transparent above and below, respectively. A pair of fixing jigs are arranged, and an annular convex portion is formed on the crimp body side of each fixing jig so as to face the annular seal portion. A pressure-bonded body gap determining device, wherein a fluid is caused to flow in both pressurizing regions surrounded by a portion and the pressure of the fluid is used to determine a gap between two transparent substrates. It is characterized in that a retardation film and a polarizing plate are arranged on the outer side, and a light source is arranged to irradiate light on either one of the fixing jigs.

According to a second aspect of the present invention, there is provided a method for manufacturing a liquid crystal display device, wherein the liquid crystal and both transparent substrates are set at a predetermined distance between a pair of fixing jigs of the pressure-bonding body gap determining device according to the first aspect. A pressure-bonding body, in which a spacer is inserted and a part of the annular seal portion is opened, is arranged, and then compressed air is caused to flow through both of the above-mentioned pressurizing areas to make a pressure of 0.1 to 0.5 Kg / cm ² transparent to both. While being added to the substrate, the irradiation light of the light source is passed through the retardation film, the polarizing plate, and the fixing jig, and the gap between the transparent substrates is confirmed by the degree of color unevenness of the passing light. The feature is that the liquid crystal is enclosed by closing the opening.

[0014]

In the crimp body gap determining device according to the first aspect, transparent fixing jigs are arranged on the upper and lower sides of the crimp body, respectively, and the fluid is caused to flow to the pressurizing region on the crimp body side of each fixing jig. The two substrates are crimped by the pressure of the fluid, and since the substantially same structure is arranged above and below the crimped body, the structural difference is eliminated and the fluid pressure is utilized. Therefore, uniform pressure is applied to the substrate surface of the pressure-bonded body, and as a result, the gap between the substrates can be adjusted to be uniform.

In addition, a retardation film and a polarizing plate are arranged outside a transparent fixing jig, and a light source is arranged to irradiate light to the pair of fixing jigs. When the light passes through the polarizing plate, it becomes linearly polarized light, and when it passes through the retardation film, it becomes elliptically polarized light. When it further passes through the pressure-bonded body made of liquid crystal or the like, it will be returned to the original linearly polarized light. If the thickness between the two substrates is non-uniform when passing through, the extent to which the original linearly polarized light is returned differs depending on the passing site.
Therefore, if the pressure-bonded body has color unevenness, the thickness between the two substrates is not uniform, so that the fluid is further flown to the pressurizing area to further increase the pressure between the two substrates. In addition, the thickness between the two substrates can be made even more uniform.

According to a second aspect of the present invention, a liquid crystal as an encapsulating material and a spacer for setting a predetermined gap between the two substrates are inserted between both fixing jigs of the crimp body gap determining device according to the first aspect. And a pressure-bonding body (liquid crystal display element cell) in which a part of the annular seal portion is opened, and then a fluid is caused to flow in both pressurizing areas to make a pressure of 0.1 to 0.5 Kg / cm ² transparent to both. In addition to the substrate, the retardation film, the polarizing plate, and the light source are then arranged as described above to check the gap between the transparent substrates according to the degree of color unevenness of the light passing through this light source. The extra liquid crystal is discharged by, and after that, the opening is closed and the liquid crystal is sealed. As a result, the gap between the substrates of the individual liquid crystal display element cells can be adjusted as required and the gap can be made constant.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pressure-bonding body gap determining device 10 of the present invention will be described in detail with reference to FIG. Further, FIG. 2 is a schematic plan view of the liquid crystal display element cell 11 which is the pressure bonded body.

In FIG. 2, this liquid crystal display element cell 11 is shown.
Is formed by laminating two transparent glass substrates 12 and 13 via an annular seal portion 14, and the annular seal portion 14 is partially formed with an opening 14a for injecting liquid crystal. Then, according to the liquid crystal display element cell 11 of FIG.
A state in which liquid crystal is injected from the opening 14a is shown.

Next, the manufacturing sequence of the liquid crystal display element cell 11 will be described. A sealant made of an epoxy resin is printed on one glass substrate, and the other glass substrate is bonded. Then, at the time of this bonding, spacers made up of a large number of resin balls are scattered to set the substrate interval to, for example, 5 to 10 μm. Further, this bonding is performed by a conventionally known crimping device, that is, a rigid crimping device that presses both substrates using a crimping jig and presses them by heating, or an air crimping device equipped with pressurized air. Using.

Next, the glass substrates 12 and 13 having the required dimensions are provided.
2, and thus, as shown in FIG. 2, an empty cell in which no liquid crystal is injected is formed by laminating the glass substrates 12 and 13 via the annular seal portion 14.

After that, liquid crystal is injected through the opening 14a. This injection is done in a vacuum chamber,
The opening 14a is brought into contact with a dish containing liquid crystal, and then the vacuum state is returned to the atmosphere to inject the liquid crystal into the empty cell.

As described above, a liquid crystal display element cell 11 into which a liquid crystal was injected was obtained. In this element cell 11, when the above liquid crystal was injected, the glass substrates 12 and 13 were caused by mechanical precision and thermal deformation. The gap between the substrates was uneven.

According to experiments conducted by the present inventor, STN is generally used.
-Type liquid crystal display device, the gap between the substrates is ±
Although it has to be set within 0.1 μm, the gap between substrates is ± 0.2 μm or more according to the above process.

Therefore, the crimp body gap determining device 1 of FIG.
0 was used to set the gap between the substrates of the liquid crystal display element cell 11. The configuration of this device 10 is as follows. The liquid crystal display element cell 11 is arranged between an upper pressure plate 15 and a lower pressure plate 16 which are fixing jigs and are made of, for example, transparent plastic. In addition, both pressure plates 15 and 16 have
A pipe 17 and a pipe 18 are provided respectively, and the pipes 17 and 18 are configured so that their ends are commonly connected to the pipe 19. The pipe 19 has a precision pressure reducing valve 2
0 and the valve 21 are connected. Reference numeral 22 is a pipe joint.

Further, on the liquid crystal display element cell 11 side of each of the pressure plates 15 and 16, annular protrusions 23 and 24 are formed so as to face the annular seal portion 14, respectively. Unlike the annular seal portion 14, the annular ridge portions 23 and 24 form a closed annular shape. A space area surrounded by the upper pressure plate 15, the liquid crystal display element cell 11 and the annular protrusion 23 is defined as a pressure area 25. Similarly, the lower pressing plate 16, the liquid crystal display element cell 11, and the annular protruding portion 24 form a pressing region 26.

Furthermore, four to six bolts 27 are provided on the upper pressure plate 15, and the two pressure plates 15 and 16 can be set at predetermined intervals by the bolts 27. In order to set the intervals with the bolts 27, the spacers 28 having a predetermined interval are passed through the bolts 27 in advance, and the bolts 27 are tightened so that the pressure plates 15 and 16 are brought close to each other to the intervals of the spacers 28. .

Further, a retardation film 29 and a polarizing plate 30 are arranged on the outer surface of the pressure plate 16. Furthermore, this device 10
A light source 31 is arranged on the lower side.

Next, a method of manufacturing a liquid crystal display element using the pressure-bonding body gap determining device 10 having the above-described structure will be described below. First, the liquid crystal display element cell 11 containing the liquid crystal and the spacer as described above is arranged between the upper pressure plate 15 and the lower pressure plate 16 and the bolt 27 is tightened. Then, the pressure is set by the precision pressure reducing valve 20, the valve 21 is opened, and the glass substrate 12 of the liquid crystal display element cell 11 is opened by the pressurizing region 25 and the pressurizing region 26 via the pipe 19 and the pipes 17 and 18.
A predetermined pressure is applied across both main surfaces of 13.

When the present inventor repeatedly conducted experiments,
0.1 to 0.5 kg / cm ² for both substrates 12 and 13
Then, the light source 31 was irradiated with light on the pair of fixing jigs 15 and 16 through the retardation film 29 and the polarizing plate 30. In the case of such a light irradiation mechanism, when the irradiation light passes through the polarizing plate 30, it becomes linearly polarized light, when it passes through the retardation film 29, it becomes elliptically polarized light, and when it further passes through the liquid crystal display element cell 11, it becomes the original linearly polarized light. If there is a difference depending on the degree to which the color is returned to, color unevenness has occurred. Therefore, if there is uneven color, it is not uniform thickness between the two glass substrates 12 and 13,
The pressure between the pressure areas 25 and 26 is further increased, and the gap between the two transparent substrates is adjusted according to the degree of color unevenness of the light passing through the light source to make the thickness between the two glass substrates 12 and 13 even more uniform. did.

After that, the opening 14a is closed to seal the liquid crystal. For this sealing, an ultraviolet curable resin was applied to the opening 14a, and the pressure was changed from a pressurized state to the inside of the opening 14a, and then ultraviolet irradiation was performed to cure and seal the resin.

The present invention is not limited to the above embodiments, and various modifications and improvements may be made without departing from the scope of the present invention.

For example, in this embodiment, the retardation film and the polarizing plate are arranged outside the fixing jig 16, but they may be arranged outside the fixing jig 15.

[0033]

As described above, according to the crimp body gap determining device of the first aspect, since the fixing jigs having substantially the same structure are arranged above and below the crimp body, there is no difference in structure between them. Since the fluid pressure is used, uniform pressure is applied across the substrate surface of the pressure-bonded body, and as a result, the gap between the substrates can be adjusted to be uniform.

Further, in the pressure-bonding body gap determining device according to the first aspect, the retardation film and the polarizing plate are arranged outside each of the pair of transparent fixing jigs, and the pair of fixing jigs are irradiated with light. Therefore, it is possible to find the relationship between the pressure of the compressed air and the color unevenness of the crimp body in the device without taking out the crimp body from the crimp body gap determining device. This makes it easier to find the optimum pressure condition, and as a result, the optimum pressure condition can be easily determined while the crimping body is still attached to the crimping body gap determining device, which improves the manufacturing efficiency. The cost could be reduced.

According to a second aspect of the present invention, a liquid crystal as an encapsulating material and a spacer for setting a predetermined gap between both substrates are inserted between both fixing jigs of the crimp body gap determining device according to the first aspect. A liquid crystal display element cell, which is a pressure-bonded body with a part of the annular seal part opened, is arranged, and then a fluid is caused to flow in both pressurizing regions to make a pressure of 0.1 to 0.5 Kg / cm ² transparent to both. In addition to the substrate, the retardation film, the polarizing plate, and the light source are then arranged as described above to check the gap between the transparent substrates according to the degree of color unevenness of the light passing through this light source. The extra liquid crystal is discharged by, and after that, the opening is closed and the liquid crystal is sealed.
The gap between the substrates of each liquid crystal display element cell can be determined as required, and the gap can be made constant, and the manufacturing efficiency can be improved and the manufacturing cost can be reduced. The element could be provided.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a crimp body gap determining device of the present invention.

FIG. 2 is a schematic plan view of a liquid crystal display element of an example.

FIG. 3 is a schematic explanatory diagram of a preceding crimp body gap determining device.

[Explanation of symbols]

 10 Pressure-bonded body gap determining device 11 Liquid crystal display element cell 12, 13 Glass substrate 14 Annular seal part 14a Opening 15 Upper pressing plate 16 Lower pressing plate 23, 24 Annular convex part 25, 26 Pressing region 29 Phase difference film 30 Polarizing plate 31 light source

Claims (2)

[Claims] 1. A pair of transparent fixing jigs are arranged above and below a pressure-bonding body formed by inserting an encapsulating material into a space between two transparent substrates and an annular seal portion between the transparent substrates. On the crimping body side of each fixing jig, an annular ridge is formed so as to face the annular seal portion, and in both pressure areas surrounded by the pair of fixing jigs, the crimping body and each annular ridge. A pressure-bonding body gap determining device configured to flow a fluid to determine a gap between two transparent substrates by the pressure of the fluid, wherein a retardation film and a polarizing plate are arranged outside the one fixing jig. A device for determining the gap of a crimping body, which is provided with a light source for irradiating light to one of the fixing jigs. 2. A liquid crystal and a spacer for setting a predetermined gap between both transparent substrates are inserted between a pair of fixing jigs of the crimp body gap determining device according to claim 1, and an annular seal portion. Of the pressure-bonded body is placed, and then compressed air is caused to flow in both of the above-mentioned pressurization regions to obtain 0.1-0.5 Kg /
A pressure of cm ² is applied to both transparent substrates, and the irradiation light of the light source is passed through the retardation film, the polarizing plate and the fixing jig, and the gap between the transparent substrates is determined according to the degree of color unevenness of the passing light. A method for manufacturing a liquid crystal display device, characterized in that after confirming, the opening is closed and liquid crystal is sealed.