JP2003043458A - Method and device for sucking substrate for liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for sucking a substrate for liquid crystal display element for the purpose of obtaining liquid crystal display element with excellent display quality even when a substrate composed of resin is used. SOLUTION: A plurality of suction ports 4 for sucking are arranged on a surface plate 2A. Distributions of the suction ports 4 in regions R1-R5 are made to be respectively different and the respective regions are independently interchanged corresponding to details of treatment for a resin substrate 3. An air blower 1 is attached to the upper side of the surface plate 2A. Air is evacuated through the suction ports 4 with a vacuum pump while imparting wind pressure to the resin substrate 3. By this procedure, no warpage is generated on the resin substrate 3 in fixing and resist treatment and treatment for formation of an alignment layer are stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display element substrate suction method using a resin substrate and a liquid crystal display element substrate suction apparatus.

[0002]

2. Description of the Related Art At present, glass is mainly used for liquid crystal display elements. In the manufacturing process of a liquid crystal display element using a glass substrate, patterning of a transparent electrode by photolithography, alignment film formation, seal printing, and the like are performed, and two glass substrates that have undergone these steps are bonded together. In these conventional manufacturing processes, the substrate is fixed by vacuum suction. This is because a substrate having rigidity such as glass does not warp on the substrate and the substrate is flat, so that it can be easily adsorbed to a flat platen. Further, due to the rigidity of the glass substrate itself, partial deformation does not occur due to vacuum suction.

[0003]

As described above, glass is mainly used for the substrate of the liquid crystal display element. However, in order to satisfy the recent demands for thinner and lighter liquid crystal display elements, the resin of the substrate is used. Is being considered. Acrylic resins, polycarbonate resins, epoxy resins, and polyethersulfone resins have been considered as materials for resin substrates, and the substrate thickness is 0.1 mm to 0.5 mm.

Unlike the glass substrate, the resin substrate is convex on the ITO forming surface side as shown in FIG. This phenomenon applies heat to the substrate during film formation in order to form a uniform ITO film, but when the substrate is cooled after the ITO film is formed,
This occurs because the resin substrate shrinks more than the ITO film. When the resin substrate is thus warped, a gap is formed over a wide range between the resin substrate 3 and the surface plate 2 when the substrate is fixed on the surface plate 2. Therefore, the substrate cannot be substantially adsorbed, and the liquid crystal display element itself cannot be manufactured. Further, if the suction force by the suction port 7 is increased in order to avoid this, suction is possible, but the suction portion becomes concave as shown in FIG. 5, and it becomes difficult to secure the flatness of the entire substrate.

In this case, unevenness of the film thickness occurs in the subsequent resist coating in the photolithography process, and as a result, the aperture ratio of the transparent electrode pattern varies. Therefore, uneven brightness occurs in the display state of the liquid crystal panel. Further, the unevenness of the thickness of the alignment film also occurs in the printing process of the alignment film, and the unevenness of the threshold value of the liquid crystal cell occurs in the display state of the liquid crystal panel. Further, there is a problem that unevenness of the film thickness of the sticker occurs in the sticker printing step, and unevenness of the gap at the time of sealing occurs in the display state of the liquid crystal panel.

The present invention has been made in view of the above problems, and a method of adsorbing a liquid crystal display element substrate for obtaining a liquid crystal display element excellent in display quality even when a resin substrate is used. Another object of the present invention is to provide a liquid crystal display element substrate suction device.

[0007]

The invention according to claim 1 of the present application is a method of adsorbing a resin substrate of a liquid crystal display element on a surface plate to perform various kinds of processing, and is divided into a plurality of parts. The resin substrate is arranged on a flat surface plate having suction ports in each region, and the resin substrate is sucked by applying suction force through the suction port, and the region above the surface plate is divided into a plurality of regions. And pressurize the resin substrate by suction from the suction port of the pressurized region, and then press one area of the adjacent divided suction port from above the surface plate and that area. Then, suction is performed from below the resin substrate to adsorb and fix the resin substrate in one area of the adjacent divided adsorption ports, and this is repeated in all the divided areas to adsorb the entire surface of the resin substrate. Characterize.

According to a second aspect of the invention of the present application, in the liquid crystal display element substrate suction method according to the first aspect, the surface plate is sucked onto the resin substrate by providing a difference in the density of the suction port for each divided region. Characterized by applying force.

According to a third aspect of the invention of the present application, in the liquid crystal display element substrate suction method according to the first aspect, the surface plate has a large density of suction ports in a peripheral portion on which a resin substrate is mounted and a central portion of the suction port is large. It is characterized in that the density of the suction port is reduced.

According to a fourth aspect of the present invention, in the suction method for a liquid crystal display element substrate according to the second aspect, the suction port of the surface plate has a high density of the suction port in a region corresponding to one side of the surface plate, and The feature is that the density of the adsorption port is made low.

According to a fifth aspect of the present invention, a surface plate having a flat suction surface having a plurality of suction ports in each of the plurality of divided areas, and a resin substrate mounted on the suction surface of the surface plate. An air blow device that applies air blow from above to press the resin substrate toward the platen side, an exhaust device that exhausts gas from the adsorption port when the resin substrate is pressed by the air blow device, and the platen And a valve that connects the suction port and the exhaust device to each area, and switches each area independently.

According to a sixth aspect of the present invention, in the liquid crystal display element substrate suction device according to the fifth aspect, the surface plate sucks onto the resin substrate by providing a difference in the density of the suction port for each divided region. Characterized by applying force.

According to a seventh aspect of the invention of the present application, in the suction device for a liquid crystal display element substrate according to the fifth aspect, the density of the suction port in the peripheral portion where the resin substrate is mounted is increased and the density of the suction port in the central portion is increased. The feature is that it is made smaller.

According to an eighth aspect of the present invention, in the liquid crystal display element substrate suction device according to the sixth aspect, the suction port of the surface plate has a high density of the suction port in a region corresponding to one side of the surface plate, and another The feature is that the density of the adsorption port is made low.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) The substrate used is an acrylic resin substrate having a thickness of 0.4 mm and a size of 300 mm × 320 mm. When the resin substrate with ITO was placed on the surface plate, the center of the substrate was about 5 mm apart from the surface plate surface. First, the substrate was washed and a resist was applied for patterning the transparent electrode by photolithography.

FIG. 1 is a sectional view of a spinner type resist coating apparatus according to the first embodiment. FIG. 2 is a plan view of a surface plate of a spinner type resist coating apparatus. 1 is an air blower for pressurization, 2 is a surface plate, 3 is a resin substrate,
4 is a partial suction port, 5 is a vacuum pump, 6 is a switching valve, and R1 to R7 are regions that are independently sucked.

The air blower 1 jets an air flow toward the resin substrate 3 arranged on the surface plate 2, and the width of the air flow is substantially equal to the width of the resin substrate 3. The air blower 1 was installed at a position 50 mm in height from the surface plate 2A. The surface plate 2A is provided with a partial suction port 4 for suction, is connected to a duct in the surface plate 2A, and is connected to a vacuum pump 5 via a switching valve 6. The diameter of the suction port is 0.
5mm to 1.0mm. The density of the suction ports 4 is changed between the portion corresponding to the central portion of the substrate and the peripheral portion of the substrate. The distance between the suction ports around the areas R1, R5 and R2, R3, R4 is 5.0 mm to 10.0 mm. The distance between the suction ports in the center is 10.0 mm to 30.0 mm. Since the resin substrate has no rigidity and bends, in the spinner type resist coating device, the periphery of the resin substrate floats due to rotation, and vacuum adsorption cannot be performed from the peripheral portion. Therefore, the density of the suction port in the portion corresponding to the periphery of the resin substrate is increased. The switching valves 6 switch the suction regions R1 to R5.

The resist coating was carried out by the spinner type resist coating device having such a structure. For adsorption of the resin substrate 3, as shown in FIG. 2, first, pressure is applied to the region R1 from above the substrate by using the air blower 1, and at the same time, the region R1 is switched by the switching valve 6 to the vacuum pump 5
It was vacuum-adsorbed so that it was connected to. As a result, the region R1 is fixed. The degree of vacuum for adsorption at this time was 0.06 MPa to 0.10 MPa. The vacuum suction of the region R1 was maintained as it was thereafter.

Next, the air blow device 1 was moved to the region R2 while being pressurized by the air blow.
The pressure at this time was 0.3 MPa to 0.5 MPa.

After that, the region R2 under pressure by the air blow was also connected to the vacuum pump 5 to perform vacuum suction. This was repeated up to the region R5 to fix the entire resin substrate.

In this method, since pressure is applied from one side of the substrate to the opposite side, it is possible to adsorb the substrate while removing the deflection of the substrate. After that, a resist was applied and the spinner was rotated to form a resist film.
At this time, the resin substrate did not peel off from the surface plate.

(Second Embodiment) In the second embodiment of the present invention, the surface plate 2B has regions R1, R2, ... R5 from above as shown in FIG. The regions R1 and R2 have a narrow gap between the partial suction ports 4 as shown in the figure, and the regions R3 and R3
R4 and R5 are configured to have a narrow interval.
Other configurations are similar to those of the first embodiment.

Next, a method of adsorbing a resin substrate when an alignment film is printed on an ITO pattern by using this surface plate and an air blower will be described. The resin substrate 3 was placed on the lift pins protruding from the surface plate 21 by the transfer arm.
Then, the lift pins were lowered and the positioning pins were used for positioning. Then, the air blow device 1 above the surface plate 2B was arranged at one end of the substrate, and vacuum suction was performed at the position of the substrate hit by the air blow at this time. The air blowing device 1 was moved from one end to the other end of the resin substrate while adsorbing. Alignment film printing is performed by transferring to an alignment film ink substrate coated on a printing plate wound on a roll. First, when printing, the printing plate and the substrate come into contact with each other, so that an adhesive force is exerted. Next, when the transfer is completed, the roll-shaped plate is separated from the front side in the traveling direction of the substrate. This time,
Since the plate and the substrate have an adhesive force, the plate exerts a force to separate the substrate from the surface plate. Therefore, the density of holes on the surface plate is different from that in the first embodiment, and the density of the suction ports in the front portion of the substrate in the traveling direction is increased.

After printing the alignment film, alignment treatment was performed by rotary rubbing using rayon cloth so as to realize STN mode liquid crystal of 250 ° twist. An opposite substrate was also prepared in the same manner, and an ultraviolet curable sealing resin mixed with 1.0 wt% of glass fiber was printed on the peripheral portion of one substrate. In the case of sticker printing as well, the substrate was adsorbed by the same method as in the case of alignment film printing.

Next, 200 beads / mm ² of resin beads having a predetermined diameter were sprayed on the other substrate, and the beads were attached to each other and the sealing resin was cured by irradiation with ultraviolet rays. After that, Δn =
A mixed liquid crystal in which a predetermined amount of a chiral agent was mixed with 0.14 ester nematic liquid crystal was vacuum-injected. After sealing with an ultraviolet curable resin, it was cured by irradiation with ultraviolet rays and then heat-treated to obtain a liquid crystal cell. Further, a liquid crystal display device was prototyped using this.

The display characteristics of the liquid crystal panel prototyped using such a manufacturing method were evaluated. As a result, the uneven brightness due to the uneven film thickness of the resist was not observed. In addition, when an alignment film was printed using this method and the display characteristics of a prototype liquid crystal panel were evaluated, the unevenness of the liquid crystal threshold due to the unevenness of the thickness of the alignment film was not observed. Further, seal printing was performed using this method to evaluate the display characteristics of a prototype liquid crystal panel, but no gap unevenness was observed during sealing due to uneven film thickness of the seal.

In the conventional manufacturing process using a resin substrate, since the warpage of the resin substrate is large, it is impossible to adsorb the substrate, or the adsorbing force causes the unevenness of brightness due to the unevenness of the resist film and the alignment film. There was unevenness in the threshold value due to the uneven film thickness and unevenness in the gap at the time of sealing due to the uneven film thickness of the seal. However, when a liquid crystal display device was manufactured by the above method, the substrate could be easily adsorbed, and a liquid crystal display device with good characteristics without unevenness was obtained.

In the above embodiment, in order to prevent the substrate from peeling in the process after adsorption,
The density of the suction port of the surface plate around the resin substrate and the position corresponding to the front of the resin substrate was partially changed, but the resin substrate with the same characteristics even if suction is performed by increasing the suction force itself of that part It is possible to obtain The pressure used for sucking the substrate and the pressure applied from above the substrate may be changed depending on the thickness of the substrate and the rigidity of the substrate. In addition, the adsorption of the substrate
The process may be performed not only from the side to the opposite side but also from the center of the substrate to the outside. Regarding the diameter of the suction port, the central portion and the peripheral portion of the substrate may have the same diameter or may have different diameters.

[0029]

As described above, according to the present invention, a warped resin substrate can be easily adsorbed on a surface plate,
It is possible to manufacture a liquid crystal display element without uneven brightness, uneven threshold, and uneven gap at the time of sealing.

[Brief description of drawings]

FIG. 1 is a sectional view of a spinner type resist coating apparatus according to a first embodiment of the present invention.

FIG. 2 is a plan view of a surface plate of a spinner type resist coating apparatus according to the first embodiment of the present invention.

FIG. 3 is a plan view of a surface plate of an alignment film printing apparatus according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a state of a resin substrate placed on a conventional surface plate.

FIG. 5 is a cross-sectional view showing a state of a resin substrate that has been adsorbed on a conventional surface plate.

[Explanation of symbols]

1 Air blow device 2A, 2B surface plate 3 resin substrate 4 Partial suction port 5 vacuum pump 6 switching valve R1-R7 area 12 Adsorption port

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Junya Yamamoto             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 2H088 FA17 FA18 FA29 FA30 HA01                       JA13 MA04                 2H090 JB03 JC02 JC12 JC14 KA08                 3C016 DA02 DA12 DA15                 5F031 CA05 HA14 MA26 PA14

Claims (8)

[Claims] 1. A method for adsorbing a liquid crystal display element substrate, wherein a resin substrate of a liquid crystal display element is adsorbed on a surface plate to perform various kinds of processing, wherein a flat surface plate having adsorption ports in each of a plurality of divided regions is provided. A resin substrate is arranged, suction force is applied to the resin substrate through the suction port to suck the resin substrate, and pressure is applied to one region divided into the plurality of regions from above the surface plate. The resin substrate is sucked and fixed by suction from the suction port, and then one area of the adjacent divided suction ports is pressed from above the surface plate, and suction is made to the one area from below the resin substrate, A method for adsorbing a liquid crystal display element substrate, which comprises adsorbing and fixing a resin substrate in one area of an adjoining divided adsorption port, and repeating this in all the divided areas to adsorb the entire surface of the resin substrate. 2. The suction of a liquid crystal display element substrate according to claim 1, wherein the platen has a different suction port density for each divided area to exert a suction force on the resin substrate. Method. 3. The surface plate according to claim 1, wherein a density of a suction port in a peripheral portion on which a resin substrate is mounted is high and a density of a suction port in a central portion thereof is low. Liquid crystal display device substrate adsorption method. 4. The suction port of the platen has a high density of suction ports in a region corresponding to one side of the platen, and a low density of other suction ports. Liquid crystal display device substrate adsorption method. 5. A surface plate having a flat suction surface having a plurality of suction ports in each of a plurality of divided areas; and air blow from above the resin substrate placed on the suction surface of the surface plate. An air blow device for pressing the resin substrate toward the surface plate side, and when the resin substrate is pressed by the air blow device,
A liquid crystal comprising: an exhaust device that exhausts the gas in the adsorption port; and a valve that connects the adsorption port and the exhaust device to each region of the surface plate, and that switches each region independently. Adsorption device for display element substrate. 6. The suction of a liquid crystal display element substrate according to claim 5, wherein the platen has a difference in the density of the suction port for each of the divided regions to apply a suction force to the resin substrate. apparatus. 7. The surface plate according to claim 5, wherein a density of a suction port in a peripheral portion on which a resin substrate is mounted is high and a density of a suction port in a central portion thereof is low. Liquid crystal display device substrate suction device. 8. The suction port of the platen has a high density of suction ports in a region corresponding to one side of the platen, and a low density of other suction ports. Liquid crystal display device substrate suction device.