JPH09218412A - Spacer spraying device and spraying method as well as liquid crystal display device produced by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly spray spacers to only the necessary parts and to remove the aggrighted spacers by selectively removing the spacers of the unnecessary parts without using fluorocarbon and alcohols in spraying of the spacers for forming a prescribed spacing between two sheets of substrates facing each other. SOLUTION: The spacers 7 are sprayed on the substrates 4 in the state of electrifying the spaces 7 and the inside wall of a spraying chamber 5 to negative and holding a spraying stage 6 grounded. Next, the substrate 4 sprayed with the spacers 7 is held in a cleaner stage 11 which are formed with microelectrode parts 12 in the positions where the spacers 7 are desired to be left and are impressed with a positive voltage and is moved under a cleaner head 14 connected to a vacuum device 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spacer spraying device and a spraying method used for manufacturing a liquid crystal display device or the like.

[0002]

2. Description of the Related Art In a liquid crystal display device, generally spherical beads (materials: silica, plastic, etc.) called spacers are used to form a predetermined space between two glass substrates facing each other. Conventionally, as a method of spraying the spacers on the substrate surface, the spacers are mixed with an organic solvent such as CFC, isopropyl alcohol, and ethanol, and sprayed into the spray chamber using a two-fluid nozzle or the like by the pressure of air or nitrogen. Wet spraying method that adheres to the substrate by natural drop, and the spacer is filled in the supply section as it is, weighs a fixed amount for each spraying and pressure-feeds it with gas such as air or nitrogen, and naturally or during operation There is a dry spraying method in which the spacer is electrically charged and the electrostatic force is used to attach the spacer to the substrate. In the dry spraying method, when the spacers are pressure-fed in the pipe by air, nitrogen or the like, the spacers themselves are charged to the same electric potential and repel each other due to the frictional force, so that the spacers are hardly aggregated. In addition, by charging the inner wall of the spray chamber to the same polarity as the charged spacer and holding the spray stage holding the substrate in the opposite polarity or the ground state, the spacer does not adhere to the inner wall of the spray chamber. It can be efficiently attached only to the surface of the substrate in contact with. Further, by forming a certain electrode pattern on the spray stage and charging the electrode pattern to the opposite polarity to the charged spacer, the spacer can be selectively attached to a part of the substrate.

For example, FIG. 3 shows a spraying apparatus using a dry spraying method disclosed in Japanese Patent Laid-Open No. 3-251821. Nozzles 9 for spraying spacers are attached to the ceiling of the spray chamber 5, and a spray stage 6 having a fine electrode portion 12 is installed below the spray chamber 5. Further, the nozzle 9 is connected to the spacer supply section 8 by a stainless pipe 10. Spacer 7 is spacer supply unit 8
Nitrogen or the like is used to apply pressure to the inside of the stainless steel pipe 10 to be charged and jetted into the spray chamber 5. Spacer 7 jetted into the spray chamber 5
Is negatively charged, the spacer 7 is efficiently and uniformly attached to the substrate 4 by negatively charging the inner wall of the spray chamber 5 and keeping the spray stage 6 positively charged or grounded. Furthermore, the microelectrode portion 12 of the spray stage 6
Are formed corresponding to the positions where the spacers 7 are to be sprinkled, and the spacers 7 are selectively attached by being positively charged or held in a grounded state. In addition, JP-A-5-6
In the 1052 publication, as shown in FIG.
In a liquid crystal display panel in which a liquid crystal is sandwiched between a transparent insulating substrate 4a in which wiring electrodes 31 are formed by a matrix method and a counter substrate in which a counter electrode is formed, a spacer 7 for keeping the thickness of the liquid crystal layer uniform. Wiring electrode 31 when spraying
A method is also proposed in which the spacer 7 is selectively attached to the wiring electrode 31 by applying a polarity opposite to that of the spacer 7 to reduce the display defect due to the spacer 7 being attached to the pixel electrode 15, that is, the pixel display portion. Has been done.

[0004]

As described above, several methods have been conventionally proposed as a method for dispersing spacers for forming a predetermined space between two opposing substrates on the surface of the substrate. Is not valid. For example, in the wet spray method, CFCs and alcohols with a low flash point, whose use is regulated as a cause of natural destruction that cannot be collected, are used, and spacers aggregated in the solvent adhere to the substrate in the aggregated state. Therefore, there is a problem that the substrate interval becomes non-uniform. Further, even in the dry spraying method, it is impossible to completely eliminate the agglomeration of the spacers 7. Even if the spacers 7 can be selectively attached to the portions other than the pixel display portion, the agglomerated spacers 7 are similarly formed on the substrate 4. The mass of the spacers 7 adhered on the inner wall of the spray chamber 5 and the peripheral portion of the nozzle 10 slips off and adheres to the substrate 4, resulting in non-uniformity of the substrate intervals, which causes a display failure in the liquid crystal display panel. There was a problem such as a cause.

The present invention has been made in order to solve the above problems. It is possible to selectively remove the spacers in unnecessary portions without using CFCs or alcohols, and to make uniform spacers only in required portions. It is an object of the present invention to provide a spacer spraying device and a spraying method capable of spraying spacers on a substrate and removing aggregated spacers. Also,
An object of the present invention is to provide a liquid crystal display device in which no display defects due to the adhesion of agglomerated spacers to a substrate and the adhesion of spacers to a pixel display portion occur.

[0006]

A spacer sprinkling device according to the present invention conveys a substrate, and a sprinkling chamber portion for sprinkling spacers for forming a predetermined space between two opposing substrates on the substrate. It is provided with a transport shuttle and a cleaner section for selectively removing the spacers scattered on the substrate. In addition, the spray chamber portion is provided with holes or nozzles that are provided in the ceiling portion and eject the spacers that are supplied from the spacer supply portion through the pipes, and a spray stage that is provided below to hold the substrate. It is a thing. Further, the spacer is pressure-fed in the pipe from the spacer supply unit into the spray chamber by air or an inert gas, and is charged by friction with the inner wall of the pipe during the pressure feeding. Further, the inner wall of the pipe is provided with irregularities so as to enhance the charging efficiency of the spacer.
Furthermore, a spacer charging device such as an electrostatic gun is provided between the spacer supply part and the hole or nozzle of the spray chamber. Further, the spraying stage is held in a polarity opposite to that of the charged spacer or a grounded state. Further, the spray chamber is charged to the same polarity as the charged spacers.

Further, the cleaner part is a cleaner stage capable of moving horizontally in a state where the substrates on which the spacers are scattered are vacuum-sucked, a vacuum device for sucking the spacers, and is connected to the vacuum device and is substantially the same as one side of the substrate. And a cleaner head having a width. Further, the cleaner section is configured so that the suction pressure and the suction flow rate can be adjusted. In addition, the surface of the cleaner stage that holds the substrate has a plurality of minute electrode portions whose polarities and potentials can be changed. Furthermore, the plurality of minute electrode portions are formed at positions corresponding to the portions of the spacers scattered on the substrate that should be left. Further, the spacer spraying method according to the present invention includes a step of charging spacers for forming a predetermined space between two facing substrates, a step of spraying the charged spacers on the substrate, and a step of spraying the spacers on the substrate. The spacers are dispersed by including a step of selectively removing the dispersed spacers. Further, the liquid crystal display device according to the present invention has a transparent insulating substrate, a pixel electrode made of a transparent conductive film formed on the transparent insulating substrate, and a gate electrode made of a metal thin film formed in the vicinity of the pixel electrode. A gate wiring, a semiconductor layer provided on the gate wiring via a gate insulating film, a pair of electrodes constituting a semiconductor element together with the semiconductor layer, a counter substrate having a counter electrode sandwiching a liquid crystal material with a transparent insulating substrate, A spacer is provided which holds the transparent insulating substrate and the counter substrate at a predetermined distance by a spacer which is scattered and selectively removed on the transparent insulating substrate.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. Hereinafter, a spacer spraying device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a spacer spraying device of the present invention. The spacer spraying device is composed of a spray chamber part for spraying spacers, a transport shuttle for transporting substrates, and a cleaner part for partially removing the spacers immediately after spraying. In the figure, 1 is a spray chamber part, 2 is a transport shuttle, 3 is a cleaner part, 4
Is a substrate, 5 is a spray chamber, 6 is a spray stage below the spray chamber 5, 7 is a spacer, 8 is a spacer supply unit, 9 is a nozzle on the ceiling of the spray chamber 5,
Reference numeral 10 is a stainless steel pipe connecting the spacer supply unit 8 and the nozzle 9 on the ceiling of the spray chamber 5, 11 is a substrate 4
Is a vacuum cleaner vacuum cleaner that can move horizontally. Reference numeral 12 denotes a microelectrode portion formed on the surface of the cleaner stage 11.
13 is a vacuum device for sucking the spacers 7 scattered on the substrate 4, and 14 is a substrate connected to the vacuum device 13
The cleaner head has a width substantially the same as one side.

Next, the spacer spraying by the spacer spraying device of the present embodiment will be described. First, the substrate 4 processed in a predetermined process is transported into the spray chamber 5 by the transport shuttle 2 and placed on the spray stage 6. The spraying stage 6 is insulated from the spraying chamber 5 and is positively charged or held in a grounded state. Next, the spacer 7 is pressure-fed from the spacer supply unit 8 through the stainless pipe 10 by the pressure of air or an inert gas. At this time, the spacer 7 is negatively charged. Here, it is also possible to increase the charging efficiency of the spacer 7 by forming irregularities in the stainless steel pipe 10 or installing a charging device such as an electrostatic gun. The charged spacers 7 are ejected from the nozzle 9 into the spray chamber 5. At this time, by negatively charging the inner wall of the spray chamber 5, the negatively charged spacer 7 does not adhere to the inner wall of the spray chamber 5, and the spray stage 6 is positively charged or is held in the ground state. The spacers 7 can be efficiently and uniformly dispersed on the surface of the substrate 4. Next, the substrate 4 on which the spacers 7 have been sprayed is transported from the spray chamber 5 to the cleaner unit 3 by the transport shuttle 2, and is vacuum-sucked to the cleaner stage 11. Next, a positive voltage is applied to the minute electrode portion 12 whose polarity and potential can be changed formed on the cleaner stage 11 to positively charge the substrate 4 on which the spacers 7 are dispersed, and in that state, the suction pressure and the suction flow rate. Adjustable vacuum device 13
It moves horizontally under the cleaner head 14 connected to. At this time, the suction pressure of the vacuum device 13 is a pressure that can remove only the aggregated spacers, for example, -80 mmA.
Set to q.

According to the present invention, since the dry spraying method is adopted, CFCs and alcohols are not used. Also,
By negatively charging the sprayed spacers 7, the spacers 7 repel each other and are dispersed and scattered. further,
By negatively charging the inner wall of the spraying chamber 5, the spacer 7 does not adhere to the inner wall of the spraying chamber 5, and the spraying stage 6 is positively charged or held in a grounded state, so that the spacer 7 is attached to the substrate 4 It can be sprayed efficiently and uniformly only on the surface. Furthermore, the agglomerated spacers 7 on the substrate 4 can be selectively removed in the cleaner portion, and the distance between the two opposing substrates can be made uniform.

Embodiment 2. FIG. 2 is a cross-sectional view of a liquid crystal display device formed using the spacer spraying device according to the present invention. In the figure, 4a is a transparent insulating substrate such as a glass substrate, 15 is a pixel electrode made of a transparent conductive film, 16 is a gate electrode having a gate wiring, 17 is a gate insulating film, and 18 is a gate insulating film 17 on the gate electrode 16. A semiconductor layer provided on the semiconductor layer 18, 19 a first protective film formed on the semiconductor layer 18, 20 an ohmic contact layer formed on the first protective film 19, 21 and 22 together with the semiconductor layer 18. A source electrode and a drain electrode having a source wiring forming a semiconductor element, and 23 are second protective films, which have a blank pattern on the pixel electrode 15. Numeral 24 is a display section, which is a pixel electrode
5 corresponds to the cut-out pattern portion of the second protective film 23 on 5. The TFT substrate 25 is composed of the above elements. 26
Is a counter substrate, which is composed of a light shielding layer 27 for shielding light on the transparent insulating substrate 4a, a coating layer 28, and a counter electrode 29. The TFT substrate 25 and the counter substrate 26 are opposed to each other, and the liquid crystal 30 is injected therebetween. At this time, the spacers 7 are scattered on the TFT substrate 25 in order to keep the substrate spacing constant. The spacers 7 are scattered by the same method as in the first embodiment. The TFT substrate 25 on which the spacers 7 are scattered is transported by the transport shuttle 2 from the spray chamber 5 to the cleaner unit 3 and is vacuum-sucked to the cleaner stage 11. Next, a positive voltage is applied to the microelectrode portion 12 formed on the cleaner stage 11. At this time, a voltage is not applied to the display section 24 by forming the fine electrode section 12 on a portion of the TFT substrate 25 other than the display section 24. Next, a voltage is partially applied to horizontally move the TFT substrate 25 vacuum-adsorbed on the cleaner stage 11 under the cleaner head 14 connected to the vacuum device 13. At this time, the microelectrode portion 12
Thus, the spacer 7 in the portion to which the voltage is applied is attached to the TFT substrate 25 by the electrostatic force, and the spacer 7 on the display portion 24 to which the voltage is not applied is selectively removed.
Further, the agglomerated spacers 7 on the portion to which the voltage is applied have a larger volume of the agglomerated spacers 7 with respect to the substrate contact area than the adhesive force to the substrate due to the electrostatic force. Removed without receiving.

According to the present invention, the aggregated spacers 7 and unnecessary portions, that is, the pixel display portions 2 of the liquid crystal display device are used.
Since the spacers adhered on the display panel 4 can be selectively removed, a display defect due to the spacers 7 adhered to the pixel display section 24 or the TFT substrate 25 and the counter substrate 26 facing each other due to the adhesion of the aggregated spacers 7 are formed. It is possible to significantly reduce display defects due to nonuniformity of the intervals.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a spacer spraying device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a liquid crystal display device on which spacers are distributed by using the spacer distribution device according to the second embodiment of the present invention.

FIG. 3 is a schematic view showing a conventional spacer spraying device of this type.

FIG. 4 is a view showing a spraying state of spacers obtained by a conventional spacer spraying device.

[Explanation of symbols]

1 spray chamber part, 2 transfer shuttle, 3 cleaner part, 4 substrate, 4a transparent insulating substrate, 5 spray chamber, 6 spray stage, 7 spacer, 8 spacer supply part, 9 nozzle, 10 stainless pipe, 11 cleaner stage, 12 Micro electrode part, 13 vacuum device, 14 cleaner head, 15 pixel electrode, 16
Gate electrode, 17 gate insulating film, 18 semiconductor layer, 1
9 first protective film, 20 ohmic contact layer, 2
1 source electrode, 22 drain electrode, 23 second protective film, 24 display section, 25 TFT substrate, 26 counter substrate, 27 light shielding layer, 28 coating layer, 29 counter electrode, 30 liquid crystal, 31 wiring electrode.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshimi Shinbori, 997 Miyoshi, Nishigoshi-cho, Kikuchi-gun, Kumamoto Prefecture, Advanced Display Co., Ltd. (72) Hirofumi Shirakura, 997 Miyoshi, Nishigoshi-cho, Kikuchi-gun, Kumamoto Prefecture・ In the display

Claims (13)

[Claims] 1. A sprinkling chamber section for sprinkling spacers for forming a predetermined space between two opposing substrates on a substrate, a transport shuttle for transporting the substrate, and spacers sprinkled on the substrate. A spacer spraying device, characterized in that it is provided with a cleaner part for removing it selectively. 2. The spray chamber section has holes or nozzles provided in the ceiling section for ejecting spacers supplied from a spacer supply section through a pipe, and a spray stage provided below for holding the substrate. The spacer spraying device according to claim 1, wherein the spacer spraying device is provided. 3. The spacer is pressure-fed in the pipe by air or an inert gas into the spray chamber from the spacer supply unit, and is charged by friction with the inner wall of the pipe during the pressure feeding. The described spacer spraying device. 4. The spacer spraying device according to claim 2, wherein unevenness is formed on the inner wall of the pipe to enhance the charging efficiency of the spacer. 5. A spacer charging device such as an electrostatic gun is provided between the spacer supply part and the hole or nozzle of the spray chamber, and the spacer charging device is any one of claims 2 to 4. Spacer spraying device. 6. The spacer spraying device according to claim 3, wherein the spraying stage is held in a polarity opposite to that of the charged spacer or in a grounded state. 7. The spray chamber is charged to the same polarity as the charged spacers.
The spacer spraying device according to claim 6. 8. The cleaner unit is connected to a cleaner stage that can move horizontally in a state where a substrate on which spacers are scattered is vacuum-sucked, a vacuum device for sucking the spacers on the substrate, and a vacuum device connected to the vacuum device. The spacer spraying device according to any one of claims 1 to 7, further comprising a cleaner head having a width substantially equal to one side of the substrate. 9. The spacer spraying device according to claim 1, wherein the cleaner portion is configured so that suction pressure and suction flow rate can be adjusted. 10. The spacer spraying device according to claim 8, wherein the surface of the cleaner stage that holds the substrate has a plurality of minute electrode portions whose polarities and potentials can be changed. 11. The spacer spraying device according to claim 10, wherein the plurality of minute electrode portions are formed at positions corresponding to portions to be left among the spacers scattered on the substrate. . 12. A step of charging spacers for forming a predetermined space between two facing substrates, a step of spraying the charged spacers on the substrate, and a step of spraying spacers on the substrate. A spacer spraying method comprising a step of selectively removing. 13. A transparent insulating substrate, a pixel electrode made of a transparent conductive film formed on this transparent insulating substrate, a gate wiring having a gate electrode made of a metal thin film formed in the vicinity of this pixel electrode, and this gate wiring. A semiconductor layer provided above with a gate insulating film, a pair of electrodes forming a semiconductor element together with the semiconductor layer, an opposite substrate having an opposite electrode sandwiching a liquid crystal material together with the transparent insulating substrate, and the transparent insulating substrate. A liquid crystal display device, comprising a spacer for holding a transparent insulating substrate and a counter substrate at a predetermined interval by a spacer which is scattered and selectively removed.