JPH10104624A - Manufacturing device for liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an obtained orientation film superior in homogeneity and obtain high productivity by thermally processing a pattern substrate coated with the orientation film by one of system groups of a heating device which thermally processes respective pattern substrates independently. SOLUTION: This device is composed of a coating device 12 which coates the pattern substrate 14 with an orientation film and a baking device 13 which thermally processes the pattern substrate 14 coated with the orientation film to obtain a homogeneous orientation film. Then the pattern substrate 14 which is elevated from a stage 16 is held by a conveyance robot 23 and fetched into the baking device 113 through a window 21. The conveyance robot 23 which holds the pattern substrate 14 moves to before one of hot plates 24a to 24d which are empty through a rail 22 to pass the pattern substrate 14 to the hot plate. Consequently, the polyimide orientation film formed on the pattern substrate 14 becomes nearly homogeneous, almost no product defect is generated, and superior display characteristics can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a liquid crystal display element used for a liquid crystal display of various information communication devices such as a personal computer, a simulation device, and a navigation system.

[0002]

2. Description of the Related Art A display using a liquid crystal displays an image by utilizing the dielectric anisotropy of the liquid crystal molecules and changing the arrangement of the liquid crystal molecules by applying a voltage. Therefore, it is necessary to control the alignment and inclination (pretilt) of the liquid crystal molecules suitable for the operation mode of the liquid crystal, and this control is achieved by using an alignment film. Therefore, in order to improve the display characteristics of a display using a liquid crystal, it is essential to obtain a stable and uniform alignment film.

Conventionally, an alignment film is obtained by applying a resin or the like constituting an alignment film on a pattern substrate on which an electrode pattern is formed, and heating and curing the resin in one line (system). I was

That is, as schematically shown in FIG. 8, a plurality of hot plates having different set temperatures are arranged in series in the same direction as the transport direction of the pattern substrate 14 coated with the alignment film, as schematically shown in FIG. For 81a to 81d, the pattern substrate 14 is sequentially transferred onto each hot plate.

[0005]

However, in the above-mentioned method, there is only one heat treatment system, so that the efficiency of heat treatment of the pattern substrate is not improved, and the productivity of the liquid crystal display element is low. Was.

Further, in the above-described method, since only one heat treatment system is used for heating the pattern substrate on which the alignment film is applied, the process from application of the alignment film to the pattern substrate until heating is performed. If it is difficult to control the time of the alignment film, and the time from applying the alignment film to the pattern substrate to performing the heat treatment becomes long, the alignment film is partially dried before the heat treatment of the alignment film. As a result, there is a problem that the display characteristics of the liquid crystal display element are deteriorated because the alignment film obtained is not uniform.

When the temperature of the atmosphere when the alignment film is applied to the pattern substrate rises due to the flow of heat from the hot plate, the alignment film is also partially dried before the heat treatment of the alignment film. As a result, there is a problem that the display characteristics of the liquid crystal display element are deteriorated because the obtained alignment film is not uniform.

The present invention has been made in view of the above conventional example, and has as its object to provide an apparatus for manufacturing a liquid crystal display element which has excellent uniformity of the obtained alignment film and achieves high productivity.

[0009]

According to the present invention, there is provided an apparatus for manufacturing a liquid crystal display element, comprising: a coating apparatus for coating an alignment film on a pattern substrate on which an electrode pattern is formed; and a pattern substrate on which the alignment film is coated. And a system group of heat generating devices for heating the alignment film by performing a single-wafer heating process.

In the apparatus for manufacturing a liquid crystal display element according to the present invention, an orientation film is applied on a pattern substrate on which an electrode pattern is formed by an application device. Next, the pattern substrate on which the alignment film has been applied is subjected to heat treatment by any of a group of heating devices that independently heat-treats each pattern substrate, and the alignment film on the pattern substrate is cured.

[0011] Further, according to the present invention, there is provided an apparatus for manufacturing a liquid crystal display element, comprising: a coating apparatus for coating an alignment film on a pattern substrate having an electrode pattern formed thereon; It is characterized by comprising a system group of a heat generating device for hardening the alignment film by performing a heat treatment, and means for cutting off the flow of heat from the system group of the heat generating device to the coating device.

In the apparatus for manufacturing a liquid crystal display element according to the present invention, the electrode pattern is formed by the coating apparatus in which the temperature of the atmosphere is adjusted by means for interrupting the flow of heat from the system group of the heating apparatus to the coating apparatus. An alignment film is applied on the pattern substrate. Next, the pattern substrate on which the alignment film has been applied is subjected to heat treatment by any of a group of heating devices that independently heat-treats each pattern substrate, and the alignment film on the pattern substrate is cured.

In the apparatus for manufacturing a liquid crystal display device according to the present invention, the pattern substrate is not particularly limited as long as a common electrode and a display electrode are formed thereon and any substrate on which an alignment film is required to be formed. Examples of such a pattern substrate include various substrates such as a TFT array substrate and a color filter substrate.

The alignment film applied on the pattern substrate is usually used for a liquid crystal display, and is not limited as long as a heat treatment is required after the application. Preferably, polyimide or the like is used. An alignment film containing the above resin as a component is applied. Polyimide is obtained by chemically thermally polymerizing polyamic acid. When applied to a pattern substrate, the polyamic acid is dissolved in a solvent such as N-methyl-2-pyrrolidone (NMP) or γ-butyrolactone. And solubilized. further,
The coating device may be any device that can apply an alignment film such as a polyimide alignment film in which polyamic acid is solubilized to a pattern substrate, and usually applies the alignment film to the pattern substrate by a method such as a printing method.

Further, as each of the heat generating devices constituting the system group of the heat generating device, a heat generating device represented by a hot plate or the like is preferably used. The system group of the heating device refers to a mode in which there are a plurality of heating device systems that heat-process one pattern substrate in a single-wafer manner, that is, independently process each pattern substrate. Therefore, one system may include one heating device, and one pattern substrate may be heated by one heating device to cure the alignment film, or one system may include a plurality of heating devices and one pattern substrate. May be heat-treated by a plurality of heating devices to cure the alignment film. In any case, in the apparatus for manufacturing a liquid crystal display element of the present invention, since there are a plurality of systems of heat generating devices for independently heating one pattern substrate, a plurality of pattern substrates can be heated simultaneously. it can.

The arrangement of each system is desirably arranged at a position where the time distance until the heat treatment is performed on the pattern substrate coated with the alignment film is constant for all the systems. The time distance does not indicate a physical distance, but is a concept that represents a time required for a predetermined requirement as a scale of the distance. This time distance can vary depending on the type and thickness of the alignment film applied to the pattern substrate, the atmosphere surrounding the pattern substrate, and the like.
When the time is set to 0 seconds, the purpose of forming a uniform alignment film can be reliably achieved.

Furthermore, the heating temperature of the heating device is determined by the thickness of the alignment film applied to the pattern substrate, the time given for drying, and the heating mode of the pattern substrate under the condition that a uniform alignment film is formed. The temperature is appropriately changed to an optimum temperature by the above method. The thickness of the alignment film applied to the pattern substrate is generally 500 to 1000 angstroms, and the pattern substrate is heated by directly contacting the pattern substrate with a heating unit of a heating device such as a hot plate. From the viewpoint of preventing the pattern substrate from being damaged, it is desirable that the pattern substrate is heated by transferring heat through the atmosphere by heat transfer without directly contacting the heat generating portion of the heating device and the pattern substrate. Usually, the heating temperature of the heating device is 500 to 1 on a pattern substrate made of non-alkali glass used for a liquid crystal display element.
In the case where a polyimide alignment film is applied to a thickness of 2,000 angstroms and the pattern substrate is heated by transferring heat through the atmosphere by heat transfer without directly contacting the heating portion of the heating device and the pattern substrate, 1 When the system consists of one heating device, the heating temperature is about 100 to 15
0 ° C., and the heat treatment time at this time is about 40 to 70
When a second system includes a plurality of, for example, two heating devices, the heating temperature is about 50 to 70 ° C. and about 100 to
The heat treatment time at this time is set to about 20 to 40 seconds and about 40 to 70 seconds, respectively.
At this time, the distance between the heat generating portion of the heat generating device and the pattern substrate is about 1 to 2 mm.

In the apparatus for manufacturing a liquid crystal display element according to the present invention, the temperature of the atmosphere when the alignment film is coated on the pattern substrate is increased by the flow of heat from the hot plate, and the alignment film is heated before the alignment film is heated. In order to prevent uneven drying due to partial drying, the means for interrupting the flow of heat from the heating device system group to the coating device includes a pressure between the heating device system group and the coating device. A method in which a difference is provided and the atmosphere is always sent to the heating device side, a method in which a system group of the heating device is appropriately separated from the coating device using a physical blocking means, for example, a shutter, or a method in which these are combined, and the like are listed. However, the present invention is not limited to these.

The present invention is applicable not only to the production of liquid crystal display elements but also to a broad sense, in order to uniformly dry a coating film applied to a substrate and to obtain a product having a uniform coating film. It goes without saying that it is possible to do so.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings. In each drawing,
The same components are denoted by the same reference numerals, and overlapping description for each drawing is omitted.

(Embodiment 1) FIG. 1 is a perspective view of an apparatus for manufacturing a liquid crystal display element according to an embodiment of the present invention.

In FIG. 1, an apparatus 1 for manufacturing a liquid crystal display element is shown.
1 includes a coating device 12 for applying an alignment film to a pattern substrate, and a baking device 13 for subjecting the pattern substrate to which the alignment film has been applied to heat treatment to obtain a uniform alignment film. The coating device 12 includes a window 15 for receiving a pattern substrate 14 on which an electrode pattern has been formed from the previous stage, and a movable stage 1 on which the received pattern substrate 14 is placed.
6. The stage 1 rotates in synchronization with the movement of the stage 16, and the stage 1
The pattern substrate 14 raised from the stage 16 by the print rolls 19 and the lift pins 20 for applying the alignment film supplied from the alignment film transfer roll 17 to the pattern substrate 14 on the printing plate 18 by using the printing plate 18 by a printing method, and a baking device in the subsequent stage 13 has a window 21 for passing. The baking device 13 is movably installed on the rail 22, and is lifted from the stage 16 by the lift pins 20.
The transfer robot 23 for taking the 4 into the inside of the baking apparatus 13 through the window 21 and the four hot plates 24 for heating the pattern substrate 14 taken into the inside of the baking apparatus 13
a to 24d and movably installed on the rail 25,
It has a transfer robot 27 for transferring the heat-treated pattern substrate 14 to the subsequent stage through the window 26.
Note that the inside of the liquid crystal display element manufacturing apparatus 11 is level 1
The same cleanliness as the clean room of No. 00 is maintained.

Next, the operation procedure of the liquid crystal display element manufacturing apparatus 11 will be described.

First, from the previous stage, the pattern substrate 14 on which the electrode pattern is formed
Placed on top. Next, the stage 16 moves to the printing roll 19.
, The print roll 19 rotates in synchronization with the movement of the stage 16, and the orientation film is applied to the pattern substrate 14 on the stage 16 when the stage 16 passes through the print roll 19. Next, stage 16
Is stopped at a predetermined position of the coating device 12, the lift pins 20 of the stage 16 are raised, and the pattern substrate 14 is raised.

Next, the pattern substrate 14 raised from the stage 16 is held by the transfer robot 23, and
1 and taken into the firing device 13. The transfer robot 23 holding the pattern substrate 14 is connected to any one of the vacant hot plates 24a to 24d via the rail 22, for example, the hot plate 24a when the hot plate 24a is vacant. And transfers the pattern substrate 14 to the hot plate 24a.

Here, the transfer robot 23, the stage 16
The operation of the hot plates 24a to 24d is shown in FIG.
This will be described with reference to FIGS.

As shown in FIG. 2, the pattern substrate 14 coated with the alignment film is
6, the arm 28 of the transfer robot 23 is inserted between the stage 16 and the pattern substrate 14, and the transfer robot 23 is slightly raised to hold the pattern substrate 14 on the arm 28 (FIG. 2 a). . The arm 28 has a structure that can be folded by a joint mechanism 29. Next, the arm 28 is folded and the arm 28 rotates (FIG. 2b). Next, when the substrate reaches a predetermined position, the arm 28 stops (FIG. 2C), and the pattern substrate 14 is placed on the four claw portions 31a to 31d of the lift mechanism 30 provided on the hot plate 24a. Then, the arm 28 rotates, and again, the arm 2
8 is inserted between stage 16 and pattern substrate 14, and these steps are repeated. As shown in FIG. 3, the lift mechanism 30 of the hot plate 24a is raised when receiving the pattern substrate 14 (FIG. 3).
a) At this time, the distance between the surface of the hot plate 24a and the pattern substrate 14 is about 50 mm.
When the heat treatment is performed on the substrate 4, the lift mechanism 30 moves down to bring the pattern substrate 14 close to the surface of the hot plate 24a (FIG. 3B), so that the distance between the surface of the hot plate 24a and the pattern substrate 14 is about 1 to 1. 2 mm. And
When the pattern substrate 14 is subjected to a heat treatment, as shown in FIG.
The pattern substrate 14 is removed from the surface of the hot plate 24a, the pattern substrate 14 is removed, and a new pattern substrate is mounted on the four claw portions 31a to 31d again, and these steps are repeated. FIG. 4 schematically shows a state where the surface of the hot plate 24a and the pattern substrate 14 are close to each other and viewed from the side.

Next, the pattern substrate 14 transferred to the hot plate 24a is moved by a lift mechanism 30 to a predetermined distance with respect to the hot plate 24a, and is heated at a preset temperature for a predetermined time. During this time, a new pattern substrate is supplied from the coating device to the baking device 13, and is sequentially placed on a vacant hot plate, for example, a hot plate 24b, 24c or 24d.
Heat treatment is performed on the pattern substrate. Finally, the heat-treated pattern substrate 14 is transferred to the transfer robot 27.
Is sent to the subsequent stage through the window 26. This situation is schematically shown in FIG. Thus, the heat treatment is successively performed on the plurality of pattern substrates one after another. The mechanism and operation of the transfer robot 27 are the same as those of the transfer robot 23 as shown in FIG.

In this embodiment, in the liquid crystal display device manufacturing apparatus 11 configured as described above, the speed at which the polyimide alignment film is applied to the pattern substrate is set to 21 m / min, and the thickness of the polyimide alignment film applied to the pattern substrate is reduced. The time from applying the alignment film on the pattern substrate to about 700 angstroms and performing the heat treatment on the pattern substrate with the hot plates 24a to 24d is about 40 seconds,
a ~ 24d surface temperature about 130 ℃, hot plate 2
The distance from the surface of 4a to 24d to the pattern substrate is about 1
ran as mm. On the other hand, using the above-described conventional liquid crystal display device manufacturing apparatus having only one heat treatment system,
The pattern substrate was processed.

As a result, in the present embodiment, the heating time of the pattern substrate on each of the hot plates 24a to 24d was 60 seconds, but since there are four heating systems, the heating time per one substrate is increased. Processing time for patterned substrate is 25
Seconds. On the other hand, in the conventional liquid crystal display device manufacturing apparatus, the processing time for one pattern substrate was 40 seconds. Therefore, the processing time for one patterned substrate was greatly reduced.

Further, in this embodiment, the polyimide alignment film formed on the pattern substrate is substantially uniform, almost no product failure occurs, and the display characteristics of the finally obtained liquid crystal panel are excellent. Was something.

Example 2 In order to determine the optimum time from the application of the alignment film to the pattern substrate to the execution of the heat treatment, the liquid crystal display device manufacturing apparatus 11 of Example 1 Exactly the same as Example 1 except that the time from application of the film to execution of the heat treatment on the pattern substrate with the hot plates 24a to 24d was adjusted to 30, 40, 50, 60 and 80 seconds. Then, the pattern substrate was processed. At each time, when the dried state of the alignment film of the pattern substrate before performing the heat treatment was confirmed, when the time until the heat treatment was performed on the pattern substrate was set to 60 seconds or more, the peripheral portion of the alignment film was formed. Dryness was observed.

Then, finally, when the display characteristics of the liquid crystal panel were examined for each, the display became uneven at the same place as the place where drying was performed. When the time required for performing the heat treatment on the pattern substrate was 50 seconds or less, no deterioration of the display characteristics was observed.

Therefore, in order not to impair the display characteristics of the liquid crystal panel, it was understood that the time required to perform the heat treatment on the pattern substrate coated with the alignment film should be 50 seconds or less. .

(Embodiment 3) In the apparatus 11 for manufacturing a liquid crystal display element according to the first embodiment, the transfer robot 2 is moved through the window 21.
3 is transferred to the hot plate 24
In the case of transporting the pattern substrate 14 from a to 24d, the transfer distance of the pattern substrate 14 differs depending on the hot plate. That is,
Since the hot plates 24a and 24d are farther from the window 21 than the hot plates 24b and 24c, the pattern substrates 14 held by the transfer robot 23
Is transported to each hot plate via the rail 22 at the same time distance, the moving speed of the transport robot 23 must be changed corresponding to the hot plate. In this case, the moving speed of the transfer robot 23 when transferring the pattern substrate 14 to the hot plates 24a and 24d is set higher than the moving speed of the transfer robot 23 when transferring the pattern substrate 14 to the hot plates 24b and 24c. There must be. Therefore, the transfer substrate 23 is used to transfer the pattern substrate 14 to the hot plate 24a.
And the stability at the time of transfer to the 24d may be reduced, and the pattern substrate 14 may be damaged due to a drop or the like. When such control is impossible, it is difficult to transport the pattern substrate 14 to each hot plate at the same time distance.

Therefore, as schematically shown in FIG. 6, the hot plate 24 in the liquid crystal display element manufacturing apparatus 11 is used.
The positions of “a” to “24d” are arranged so as to be physically equidistant from the window 21, and the pattern substrate 14 held by the transfer robot 23 through the window 21 is placed on the hot plates 24 a to 24 d.
The transfer distance of the pattern substrate 14 when transporting the substrate to the position d is made equal. Then, using the same manufacturing apparatus as the liquid crystal display element manufacturing apparatus 11 except for the above configuration, the pattern substrate was processed under the same conditions as in Example 1.

As a result, the processing time per one patterned substrate was 25 seconds, and the processing time per one patterned substrate was greatly reduced as compared with the conventional liquid crystal display device manufacturing apparatus.

Of course, also in this embodiment, the polyimide alignment film formed on the pattern substrate is almost uniform, almost no product failure occurs, and the display characteristics of the finally obtained liquid crystal panel are excellent. Was something.

(Embodiment 4) In the liquid crystal display element manufacturing apparatus 11 of Embodiment 1, the hot plates 24a to 24d
The heat generated by the heat itself and the atmosphere warmed by the generated heat flow into the coating device 12 through the window 21,
There is a possibility that the alignment film applied to the pattern substrate 14 placed on the stage 16 may be dried before the heat treatment. Therefore, as schematically shown in FIG. Is provided, and the coating device 1 is
The shutter 71 is opened only when the pattern substrate 14 is transferred from the second to the baking device 13. Further, the atmosphere was allowed to flow from the coating device 12 to the firing device 13, and the flow of the atmosphere from the firing device 13 to the coating device 12 was completely prevented. Then, using the same manufacturing apparatus as the liquid crystal display element manufacturing apparatus 11 except for the above configuration, the pattern substrate was processed under the same conditions as in Example 1.

As a result, the influence of heat generated from the hot plates 24a to 24d of the baking device 13 could be completely cut off, and the alignment film applied to the pattern substrate 14 dries before the heat treatment. Is completely prevented, the polyimide alignment film formed on the pattern substrate is almost completely homogeneous, the occurrence of product defects is almost suppressed, and the display characteristics of the finally obtained liquid crystal panel are also excellent. there were. Also, needless to say, the processing time per one pattern substrate is greatly reduced.

[0041]

As described in detail above, according to the apparatus for manufacturing a liquid crystal display element of the present invention, the pattern substrate on which the alignment film is applied is a system of a heat generating device for independently heating each pattern substrate. Since the heat treatment is performed by any of the systems in the group, it is possible to provide an apparatus for manufacturing a liquid crystal display element having excellent uniformity of the obtained alignment film and achieving high productivity.

Further, according to the liquid crystal display element manufacturing apparatus of the present invention, the electrode pattern is controlled by the coating apparatus in which the temperature of the atmosphere is adjusted by means for cutting off the flow of heat from the system group of the heating apparatus to the coating apparatus. An alignment film is applied on the pattern substrate on which is formed, and the pattern substrate on which the alignment film is applied is subjected to heat treatment by any of the systems of a heating device system for independently heating each pattern substrate. It is possible to provide an apparatus for manufacturing a liquid crystal display element in which defects in homogeneity of the obtained alignment film are almost completely prevented and high productivity is achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of an apparatus for manufacturing a liquid crystal display element according to an embodiment of the present invention.

FIG. 2 is a diagram showing operations of a transfer robot 23, a stage 16, and hot plates 24a to 24d.

FIG. 3 is a view showing the operation of hot plates 24a to 24d.

FIG. 4 shows the surface of the hot plate 24a and the pattern substrate 1.
The figure which showed typically the state seen from the side when 4 and approached.

FIG. 5 is a diagram schematically showing a state in which a plurality of pattern substrates are successively subjected to a heat treatment one after another.

FIG. 6 is a diagram schematically showing a configuration of a baking apparatus when a transfer distance of a pattern substrate 14 is equalized.

FIG. 7 is a diagram schematically showing an apparatus for manufacturing a liquid crystal display element having a window provided with a shutter 71;

FIG. 8 is a diagram schematically showing a process of forming a conventional alignment film.

[Explanation of symbols]

11 ... Liquid crystal display device manufacturing apparatus 12 ... Coating apparatus 13 ... Baking apparatus 14 ... Pattern substrate 15 ...
... Window 16 ... Stage 17 ... Orientation film transfer roll 18 ... Printing plate 19 ... Print roll 20 ... Lift pin 21 ... Window 22 ... Rail 23 ... Transport robot 24a to 24d ... Hot plate 25 ... Rail 26 Window 27 Transfer robot 28 Arm 29 Joint mechanism 30 Lift mechanism 31a-
31d: Claw portion 71: Shutter 81a to 81d: Hot plate

Claims (4)

[Claims] A coating device for applying an alignment film on a pattern substrate on which an electrode pattern is formed; and a heating device for heating the pattern substrate on which the alignment film is applied in a single-wafer manner to cure the alignment film. A system group of devices;
An apparatus for manufacturing a liquid crystal display element, comprising: 2. An application device for applying an alignment film on a pattern substrate on which an electrode pattern is formed, and a heating device for heating the pattern substrate on which the alignment film is applied in a single-wafer manner to cure the alignment film. An apparatus for manufacturing a liquid crystal display element, comprising: a system group of devices; and a means for interrupting the flow of heat from the system group of the heating device to the coating device. 3. The system group of the heat generating device is arranged such that a time distance from application of the alignment film to the pattern substrate to heat treatment of the pattern substrate coated with the alignment film is constant. The apparatus for manufacturing a liquid crystal display device according to claim 1, wherein: 4. The apparatus according to claim 3, wherein the time distance is at most 50 seconds.