JPH10165866A - Coating applicator for hard substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the flawing at the primer coating layer of the rear surface at the front edge of a hard substrate by forming a first pushing up member of a plate material which is parallel and perpendicular in the advance direction of this hard substrate and is inclined at its top edge and forming a second pushing up member of a tongue-shaped part which is made gradually higher in the progressing direction of the hard substrate and is wider in the transverse direction of the hard substrate. SOLUTION: The first pushing up member 30 is formed by perpendicularly folding and erecting one side of the rectangular and horizontal lower plate 30a. The top edge of the erecting part 30b formed of this plate material is provided with a slope 30c viewed from its flank. This slope is positioned to be paralleled with the transporting direction of a glass substrate 10. The lower plate 30a is screwed to the bottom 34a of a notch 34. The second pushing up member 32 is provided with a base plate 32a fixed to the bottom 34a of the notch 34 and the tongue-shaped part 32b extending diagonally upward into a coating liquid vessel through the top edge of a rising wall 12a rising upward from this base plate 32a, by which the front edge of the glass substrate pushed up by the slope 30c of the first pushing up member 30 is further risen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard substrate coating apparatus used for manufacturing a liquid crystal display panel and the like using a glass substrate and for applying a coating liquid such as a photoresist to a hard substrate in a thin and uniform manner. is there.

[0002]

2. Description of the Related Art In a manufacturing process of a liquid crystal plate, there is a process of applying a coating liquid such as a photoresist to a thin and uniform thickness on a hard substrate such as a glass substrate. For example, in the production of a color liquid crystal plate, a transparent electrode is formed on a glass substrate in advance,
After uniformly applying a red color mosaic liquid having the function of a photoresist, the color mosaic corresponding to the red color is cured by exposure, and an excess liquid is removed to form a red color mosaic. . The same processing is repeated for other colors such as green, blue, black, and transparent. When a coating liquid to be a photoresist is applied as described above, the liquid needs to be strictly controlled to have a uniform thickness (for example, about 1 μ ± 3%) and to be applied thinly. This is because if the thickness of the coating is non-uniform, the light transmittance becomes uneven, which leads to a deterioration in quality.

Conventionally, a spin coater has been used for this coating. In this spin coater, a coating liquid is dropped near a rotation center of a rotated substrate, and the liquid is applied by scattering using a centrifugal force. However, in the method using the spin coater, not only the time and labor efficiency for replacing the substrate are deteriorated, but also the amount of the liquid scattered and discarded increases. For this reason, there was a problem that the cost was increased.

In view of this, it has been considered to use an apparatus for coating a substrate between a pair of upper and lower rollers disposed horizontally. In this device, the lower part of the micro rod bar, which is the lower roller, is immersed in the coating solution, and the substrate is sandwiched between the micro rod bar and the nip roller located above the micro rod bar. It is to be applied.

Here, the micro rod bar is formed by winding a thin metal wire in close contact with the surface of a metal rod having a circular cross section, and applies a liquid by utilizing a capillary phenomenon caused by a groove between the metal wires.

[0006]

2. Description of the Related Art Here, since a glass substrate is conveyed while both right and left edges are placed on a conveying roller and a central portion is floated, the glass substrate bends so that the central portion is curved downward.

[0007] The amount of deflection varies depending on the thickness and width of the glass substrate. For example, in the case of a thickness of 1.1 mm, the amount of deflection is small, but the thickness is 0.7 mm and the width × length is 300 × 40.
0.8mm for 400mm
(Mm) is about 2.4 mm, 500 × 600 (m
m) is about 5.3 mm. As described above, when the width and the length of the glass substrate increase, the weight increases, and therefore, the amount of flexure also increases rapidly.

When the vicinity of the center of the front edge of the glass substrate bends downward, the vicinity of the center of the front edge first comes into contact with the rotating micro rod bar and is lifted up, and is sandwiched between the micro rod bar and the nip roller. This bending disappears.

Until the bending disappears, a larger amount of liquid is stored on the lower surface near the center of the front edge of the glass substrate than on both sides thereof as the microrod bar rotates. For this reason, there is a problem that the coating thickness on the lower surface near the center of the front edge of the glass substrate is increased.

The applicant of the present application has proposed that the glass substrate be pushed up near the center of the front edge of the glass substrate immediately before entering the micro rod bar (Japanese Patent Application No. Hei 8-8896).
No. 5). That is, a push-up member is provided on the entrance side of the glass substrate so as to be able to move up and down.

The push-up member used here makes a sharp contact point contact the lower surface of the glass substrate. The contact point will continue to rub the lower surface of the glass substrate from the time the leading edge of the glass substrate passes through the contact point to the time when it enters the micro rod bar.

That is, the push-up member has an inclined surface in front of the contact point, and this inclined surface contacts the front edge of the glass substrate, so that the lower surface of the glass substrate is not rubbed, but the front edge of the glass substrate is contacted. After passing through, the glass substrate rises from the inclined surface, and the lower surface of the glass substrate comes into point contact with this contact point. Usually, the rubbing distance is about 6 mm.

When the glass substrate moves while the contact point is in point contact with the lower surface near the front edge of the glass substrate, the undercoat layer of the glass substrate may be damaged, or the undercoat layer may be peeled off to cause dust. Become. For this reason, there was a problem that the coating quality deteriorated.

[0014]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and when the center of the front edge of the hard substrate is pushed up on the entry side of the micro rod bar, the undercoat layer on the lower surface of the front edge of the hard substrate is formed. An object of the present invention is to provide a hard substrate coating apparatus suitable for improving coating quality by preventing scratches and peeling of an undercoat layer to generate dust.

[0015]

According to the present invention, this object is achieved by sandwiching a hard substrate between a micro rod bar whose lower part is immersed in a coating solution tank and a nip roller opposed to and disposed above the micro rod bar. In a hard substrate coating apparatus that applies a coating liquid to the lower surface of the hard substrate by feeding, a transfer roller that transfers the hard substrate by rolling and contacting the lower surface of both side edges of the hard substrate, and a hard substrate entry side of the micro rod bar. A first push-up member that pushes up the front edge of the hard substrate from below as the hard substrate enters, and pushes up the lower surface of the hard substrate continuously with the first push-up member to raise the front edge of the hard substrate. A second push-up member for guiding the micro-rod bar near an upper edge thereof, wherein the first push-up member is formed of a plate material whose upper edge is inclined parallel to and perpendicular to the direction in which the hard substrate enters, and The lifting member moves in the direction of travel of the hard substrate. It is achieved by hard substrate coating apparatus, characterized by having a high and hard wide tongue in the substrate width direction.

Here, it is desirable that the pressure applied to each of the first and second push-up members provided in a plurality is reduced. These push-up members are preferably fixed to the application liquid tank, but at least the second push-up member may be movable up and down.

Further, an air jet nozzle for pushing up the lower surface of the hard substrate by air pressure upstream of the first or second pushing-up member may be added. In this case, the nozzle may inject air at least between immediately before the leading edge of the hard substrate separates from the second push-up member and immediately after contacting the microrod bar. The nozzle is preferably jetted in a direction away from the coating solution tank, that is, in a direction toward the entrance of the glass substrate, in order to prevent the jetted air flow from disturbing the coating solution surface in the coating solution tank.

[0018]

FIG. 1 is an overall layout view of one embodiment of the present invention.
FIG. 2 is a perspective view of a main part thereof, FIG. 3 is a plan view showing the arrangement of the first and second push-up members, FIG.
Is a sectional view taken along line VV in FIG. 4, and FIG. 6 is a perspective view of a push-up member.

In FIGS. 1 and 2, reference numeral 10 denotes a glass substrate used for a color filter of a liquid crystal plate, which serves as a hard substrate. The glass substrate 10 has a width of, for example, 300 to 7
It is 00 mm, 400-900 mm in length and 0.7 mm in thickness.

Reference numeral 12 denotes a coating solution tank, and 14 denotes a micro rod bar. The micro rod bar 14 is formed by winding a thin metal wire tightly around the surface of a rod having a circular cross section, and applies a liquid by utilizing the capillary phenomenon caused by a groove between the metal wires. The micro rod bar 14 traverses the coating solution tank 12.

An intermediate portion of the micro rod bar 14 is supported from below by a backup member 16. The backup member 16 is made of a hard synthetic resin having excellent slidability, and an arc-shaped groove formed on the upper surface thereof along the longitudinal direction abuts on the micro rod bar 14 from below. To prevent bending.

The coating liquid is supplied to the coating liquid tank 12, and its liquid level is controlled to be constant so that the lower part of the micro rod bar 14 is sufficiently immersed. The outer diameter (diameter) of the micro rod bar 14 used here is about 6 to 12 mm.
A nip roller 20 is rotatably held above the micro rod bar 14 while maintaining a predetermined gap.

One end (the end on the rear side in FIG. 1) of the micro rod bar 14 protrudes rearward from the coating solution tank 12, and this protruding end is connected to an electric motor by a joint. The rotation of the electric motor is also transmitted to the transport roller 22 so that the feed speed of the glass substrate 10 is equal to the transport speed of the transport roller 22. The surface of the nip roller 20 is made of conductive rubber, and is held so as to apply a predetermined clamping force to the glass substrate 10 with the glass substrate 10 sandwiched between the nip roller 20 and the micro rod bar 14.

The transport roller 22 contacts only the lower surfaces of the left and right edges of the glass substrate 10. The transport roller 22 is driven by a drive mechanism housed in a case 24 shown in FIG.
The glass substrate 10 is transported at a constant speed.

The glass substrate 10 is conveyed from the left side in FIGS. 1 and 2 with its left and right edges placed on the conveyance rollers 22, and its front edge enters between the micro rod bar 14 and the nip roller 20. Thereafter, the liquid is fed to the right side at a constant speed by the rotation of the nip roller 20 and the micro rod bar 14, and the liquid is applied to the lower surface of the glass substrate 10 by the micro rod bar 14 during that time.

3 to 6, reference numeral 30 denotes a first lifting member,
Reference numeral 32 denotes a second lifting member, which is fixed to the wall 12a of the coating liquid tank 12 on the side where the glass substrate 10 enters. That is, the micro rod bar 14 is provided on the wall 12a.
Three notches 34 are formed in the vicinity of the center of the notch, and these push-up members 30 and 32 are fixed to these notches 34.

The notch 34 is opened upward and on the glass substrate entry side, and its bottom 34a is made horizontal. As is clear from FIGS. 4 to 6, the first push-up member 30 is obtained by vertically erecting one side of a rectangular horizontal lower plate 30 a, and is provided on an upright portion 30 b formed of this plate. The edge is an inclined surface 30c as viewed from the side (FIG. 5). The slope 30c is lower on the glass substrate entry side, and the wall 12 is on the wall 1 side.
2a is slightly higher than the upper edge. The first push-up member 30 is positioned such that the upright portion 30b is parallel to the direction perpendicular to the micro rod bar 14, that is, parallel to the direction of transport of the glass substrate 10, and the lower plate 30a is cut out.
Is screwed to the bottom 34a.

The second lifting member 32 is provided at the bottom 3 of the notch 34.
A substrate 32a is fixed to the substrate 4a, and a tongue 32b rises upward from the substrate 32a, passes through the upper edge of the wall 12a, and extends obliquely upward into the coating liquid tank 12. The tongue 32b is linearly inclined in a side view (FIG. 5), and has a wide width in the longitudinal direction of the micro rod bar 14.

The first lifting member 30 is fixed to the two notches 34 on both sides of the three notches 34, respectively.
The push-up member 32 is fixed to each of the three notches 34. Here, the tongue 32b of the second push-up member 32
As shown in FIG. 5, the micro rod bar 14 extends to a position slightly lower than the upper edge.

For this reason, when the glass substrate 10 is conveyed, and the front edge whose central portion is curved downward contacts the inclined surface 30 c of the first push-up member 30, the front edge is moved to the inclined surface 3 c.
It is guided by 0c and rises. Thereafter, the leading edge comes into contact with the tongue 32b of the second push-up member 32, and further rises, and is guided to the upper edge of the micro rod bar 14.

At this time, the front edge of the glass substrate 10 is
During the contact with c, only the lower corner of the front edge is in contact with the inclined surface 30c (line contact), so that nothing contacts the lower surface of the glass substrate 10. Even before the front edge protrudes before the tongue 32b of the second push-up member 32, only the lower corner of the front edge contacts the tongue 32b (line contact). Does not contact the lower surface of the tongue 32b.

For this reason, the front edge of the glass substrate 10 is
Until it protrudes beyond 2b, nothing touches the lower surface of the glass substrate 10, and there is no risk of damaging the lower surface. When the front edge of the glass substrate 10 projects from the tongue 32b, the tip of the tongue 32b rubs the lower surface of the glass substrate 10. However, since the tongue-shaped portion 32b is wide, the contact pressure on the lower surface of the glass substrate 10 is reduced, and there is no possibility of damaging the lower surface of the glass substrate 10. Further, there is no possibility that dust is generated by shaving the undercoating treatment layer of the glass substrate 10.

In this embodiment, air pressure is used to further reduce the contact pressure when the tongue 32b rubs the lower surface of the glass substrate 10. That is, as shown in FIGS. 3 to 5, a pair of left and right air jet nozzles 40, 40 are provided on the glass substrate entry side of the first push-up member 30, and the vicinity of the center of the glass substrate 10 is moved by the air pressure injected by the nozzles 40. It pushes up.

As shown in FIG. 5, the nozzles 40 and 40 are attached to a holding block 44 fixed to a base 42, and the direction of air injection is the same as the direction in which the glass substrate 10 enters, that is, the direction farther from the coating solution tank 12. Is done. This is nozzle 40
The purpose of this is to prevent the air flow jetted from generating turbulence on the coating liquid surface of the coating liquid tank 12.

It is sufficient that the nozzle 40 injects air between the time immediately before the front edge of the glass substrate 10 passes through the tongue 32b and the time immediately after it enters the upper edge of the microrod bar 14. However, the nozzle 40 has a tongue 32 at the leading edge.
It is also possible to inject air before passing through b. For example, the front edge is the inclined surface 30 c of the first push-up member 30.
Alternatively, the contact pressure during contact with the inclined surface of the tongue 32b may be reduced.

In this embodiment, two sets of first lifting members 3
Although 0 and three sets of the second push-up members 32 are used, the number used is, of course, not limited to this. The first and second push-up members 30 and 32 are fixed to the coating solution tank 12,
These or at least the second lifting member 32 may be made movable up and down. For example, the second push-up member 32 can be moved up and down so that the front edge of the glass substrate 10 is
4 until it comes into contact with the upper edge of the glass substrate 10, and then immediately lower to reliably prevent contact with the lower surface of the glass substrate 10.

[0037]

According to the first aspect of the present invention, as described above, the first push-up portion plate formed of a plate material parallel and perpendicular to the direction of entry of the hard substrate and having an inclined surface at the upper edge, A second push-up member having a wide tongue to further raise the leading edge of the raised hard substrate, so that when the leading edge of the hard substrate passes through the tongue, Even if the lower surface is rubbed, the contact pressure is reduced.

Therefore, there is no fear that the tongue-like portion scratches the undercoat layer on the lower surface of the hard substrate, and there is no danger of scraping the undercoat layer of the hard substrate to generate dust. Here, if the first and second lifting members are fixed to the coating liquid tank, the structure is simple.
However, at least one of them may be movable up and down.

If an air jet nozzle for blowing air to the lower surface of the hard substrate to push up the hard substrate is added on the hard substrate entry side of the first and second push-up members, while the tongue portion rubs the lower surface of the hard substrate, Can be further reduced, and the effect of the present invention becomes more remarkable (claim 3). In this case, the nozzle only needs to inject air during the period from just before the leading edge of the hard substrate leaves the tongue until it comes into contact with the micro rod bar. Is preferably not generated (claim 4). Therefore, it is preferable that the direction of the air jet of the nozzle be away from the coating liquid tank (claim 5).

[Brief description of the drawings]

FIG. 1 is an overall layout view of an embodiment of the present invention.

FIG. 2 is a perspective view of a main part thereof.

FIG. 3 is a plan view showing an arrangement of a push-up member.

FIG. 4 is an enlarged view of a part of FIG.

FIG. 5 is a sectional view taken along line VV in FIG. 4;

FIG. 6 is a perspective view of a push-up member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Glass substrate as a hard substrate 12 Coating liquid tank 14 Micro rod bar 30 1st push-up member 30b Standing part as a plate material 30c Inclined surface 32 2nd push-up member 32b Tongue 40 Air injection nozzle

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masafumi Ozaki 1005 Koizono, Ayase-shi, Kanagawa Prefecture Inside Fuji Mike Rographix Co., Ltd. (72) Inventor Shinya Yamazaki 1005 Kozono, Ayase-shi, Kanagawa Prefecture Fuji Micrographix Co., Ltd.

Claims (5)

[Claims] 1. A hard substrate is sandwiched between a micro rod bar whose lower part is immersed in a coating solution tank and a nip roller opposed to and disposed above the micro rod bar, and is sent to the lower surface of the hard substrate. In a hard substrate coating apparatus that applies a coating liquid, a transport roller that rolls on the lower surface of both side edges of the hard substrate and transports the hard substrate, and is provided on the hard substrate entry side of the micro rod bar and accompanies the entry of the hard substrate. A first push-up member that pushes up the front edge of the hard substrate from below, and pushes up the lower surface of the hard substrate continuously with the first push-up member to bring the hard substrate front edge near the upper edge of the micro rod bar. A second push-up member for guiding, the first push-up member is formed of a plate material whose upper edge is inclined parallel to and perpendicular to the direction of entry of the hard substrate,
The hard substrate coating apparatus, wherein the second push-up member has a tongue portion that is gradually higher in a moving direction of the hard substrate and wider in a width direction of the hard substrate. 2. The hard substrate coating apparatus according to claim 1, wherein the first and second push-up members are both fixed to a coating liquid tank. 3. The hard substrate coating apparatus according to claim 1, further comprising an air injection nozzle provided upstream of the first or second lifting member to blow air to a lower surface of the hard substrate to push up the hard substrate. 4. The air jet nozzle according to claim 1, wherein the front edge of the hard substrate is the second
4. The hard substrate coating apparatus according to claim 3, wherein air is jetted immediately before leaving the push-up member and immediately after coming into contact with the micro rod bar. 5. The hard-substrate coating apparatus according to claim 3, wherein the air-injection nozzle injects air in a direction in which the hard substrate enters.