JP3555786B2 - Micro rod bar for hard substrate coating equipment - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a micro rod bar used in a hard substrate coating apparatus that applies a coating liquid such as a photoresist to a hard substrate thinly and uniformly in order to manufacture a color filter or the like of a liquid crystal display panel.
[0002]
[Prior art]
In a manufacturing process of a color filter used for a liquid crystal plate, there is a step 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, after uniformly applying a black coating solution having a photoresist function to a glass substrate on which a transparent electrode has been formed in advance, exposing it to cure a mosaic or striped pattern corresponding to black, and removing excess photoresist. Is removed to form a black color mosaic (or stripe). The same processing is repeated for colors such as red, green, and blue.
[0003]
When a coating liquid to be a photoresist is applied as described above, it is necessary to strictly control this liquid to a uniform thickness (for example, about 2 μm ± 5%) and to apply the thin liquid. This is because if the thickness of the coating is non-uniform, the light transmittance becomes uneven and the quality is reduced.
[0004]
Conventionally, a spin coater has been used for this coating. In this spin coater, a coating liquid is dropped near the center of rotation of a hard substrate that has been rotated, and the liquid is applied by scattering using a centrifugal force. However, in the method using the spin coater, not only the labor efficiency for replacing the hard substrate is deteriorated, but also the amount of the liquid scattered and discarded increases. For this reason, there was a problem that the cost was increased.
[0005]
Further, in order to prevent contamination (dirt), it is necessary to frequently wash the liquid that has scattered and adhered to the surroundings using a solvent. Therefore, there is a problem that not only the work is troublesome, but also the operation rate of the apparatus is reduced.
[0006]
Therefore, it has been considered to apply a hard substrate between a pair of upper and lower rollers disposed horizontally. In this apparatus, the lower part of the micro rod bar serving as the lower roller is immersed in the coating liquid, and the hard substrate is sandwiched between the micro rod bar and the nip roller positioned above the micro rod bar and sent. It is applied to the lower surface.
[0007]
The micro rod bar used here is a metal rod such as stainless steel which can be soldered, and a thin metal wire such as stainless steel is densely wound thereon, and its outer diameter (diameter) is 2.0 to 20.0 mm. In particular, those having a diameter of about 12 mm are often used.
[0008]
The wire needs to be wound uniformly in the coating range, but the winding state in the vicinity of both ends of the coating range tends to be non-uniform in particular, depending on how the wires are treated at both ends.
[0009]
FIG. 7 is a cross-sectional view showing a conventional wire end processing structure, and FIG. 8 is a right side view of a part of the structure. In this figure, reference numeral 1 denotes a metal rod having a diameter of about 12 mm, which is made of solderable stainless steel or the like. The metal rod 1 has a constant diameter in the range of the application range L, and is formed in a substantially conical shape on both outer edges in the axial direction of the application range L so that the inner side enters the application range L. End faces 2 and 2 are formed. The small-diameter portions 3, 3 are formed outside the end surfaces 2, 2 in the axial direction. Here, the application range L is about 100 to 1000 mm.
[0010]
Reference numeral 4 denotes a thin metal wire such as stainless steel (having a diameter of 50 to 500 μm, particularly about 100 μm in many cases), which is tightly wound around the application range L of the metal rod 1. Here, both ends 5, 5 of the wire 4 are inserted into small holes 6, 6 formed near both edges of the application range L of the metal rod 1 and fixed by solder 7 (only shown on the left side in FIG. 7). .
[0011]
Since the small holes 6, 6 are located within the coating range L from the end faces 2, 2, the solder is placed in a predetermined range M (minimum 3 mm, usually about 4 mm) including the small holes 6, near both ends of the coating range L. 7A is piled up, and the solder 7A thus piled is cut or polished so as to have the same outer diameter as the winding outer diameter of the wire 4.
[0012]
Also, in place of the method in which the solder 7A is placed near both edges of the application range L and the solder 7A thus placed is cut as described above, both ends of the wire are spot-welded, glued, brazed, or the like. A method of fixing to a surface has been proposed (JP-A-6-226189).
[0013]
This method avoids the problem of using solder. In other words, when solder is used, the corrosion of the solder progresses in a porous manner due to the ultrasonic cleaning of the micro rod bar, and if this solder is present on the applied surface, the solder falls off and adheres to the applied surface, thereby contaminating the applied surface. This causes a problem of lowering the uniformity. This method does not use solder to prevent this problem.
[0014]
[Problems of the prior art]
In the conventional method shown in FIGS. 7 and 8, it is difficult to keep the outer diameter constant when cutting or polishing the solder 7A provided on both ends of the application range L.
[0015]
That is, as shown in FIG. 7, the range M on which the solder 7A is provided is wide, or the hardness of the solder 7A is significantly softer than that of the wire 4, so that the solder 7A is cut or polished on the end face 2 side compared with the wire 4 side. It progresses quickly, and the outer diameter of the solder 7 becomes thinner as it approaches the end face 2. For this reason, the outer periphery of the solder 7 becomes thin and tapered toward the end face 2, and a so-called "drip" occurs.
[0016]
As described above, when the outer diameter of the micro rod bar 1 becomes slightly thin near both ends of the coating range L, the coating thickness of the coating liquid becomes thick near both edges of the hard substrate, or periodic coating unevenness occurs. And uniform coating cannot be performed.
[0017]
Further, since a hard metal such as stainless steel is usually used for the wire 4, when the ends 5 are bent to be inserted into the small holes 6, the bent portion has a relatively large radius of curvature. The wire 4 swells in the outer diameter direction just before entering the wire 6.
[0018]
Therefore, when cutting the solder 7A arranged as described above, the swollen portion 4A of the wire 4 is also cut at the same time. As a result, the swelling portion 4A is cut off to reduce the diameter of the wire 4, and the wire 4 is easily broken or broken from this portion.
[0019]
On the other hand, the method of using spot welding or the like instead of using solder has a problem that the terminal treatment of the wire becomes complicated. That is, if the end of the wire is fixed to the outer peripheral surface of the metal rod by spot welding or the like, it is necessary to cut the wire at the end of the wire from the spot welded portion. It is very difficult to match the edge of the application range L. Further, since traces of spot welding remain on the surface of the micro rod bar, there is a problem that the application surface is periodically disturbed.
[0020]
[Object of the invention]
The present invention has been made in view of such circumstances, and does not cause uneven coating due to "drip" on the outer peripheral surface as in the case of cutting solder put on both ends of the wire, and the bent portion of the wire is cut. Provided is a micro-rod bar of a hard substrate coating apparatus which does not easily break and has no risk of troublesome processing of a wire terminal and occurrence of disturbance on a coating surface due to welding traces as in the case of using spot welding or the like. The purpose is to:
[0021]
Configuration of the Invention
According to the present invention, the object is to apply the coating liquid to the lower surface of the hard substrate by immersing the lower part in the coating liquid tank and sending the hard substrate between the nip roller and the nip roller disposed above and facing the nip roller. In a micro rod bar of a hard substrate coating device, a metal rod having a small diameter portion formed on both sides in the axial direction of a coating range through an end face, and a thin metal wire densely wound around the coating range of the metal rod. A pair of cutouts facing the end face and the coating range are formed at both ends of the coating range of the metal rod, and both ends of the wire are respectively engaged with these cutouts and fixed. This is achieved by the micro rod bar of the substrate coating device.
[0022]
Here, solder can be applied to only a small area at both ends of the application area, and the solder can be cut or polished to the outer diameter of the wire tightly wound portion. It is desirable to form grooves for guiding the wires to the notches near both edges of the application area in the metal rod.
[0023]
【Example】
FIG. 1 is an overall layout view of a hard substrate coating apparatus using one embodiment of the present invention. This coating apparatus applies a photoresist in a color filter manufacturing process. 2 is a plan view of the coating apparatus, FIG. 3 is a front sectional view thereof, FIG. 4 is a sectional view taken along line VI-VI in FIG. 3, and FIG. 5 is a sectional view showing a terminal treatment structure of a micro rod bar according to the present invention. 6 is a right side view thereof.
[0024]
In FIG. 1, reference numeral 10 denotes a rectangular (rectangular) glass substrate, and 12 denotes a roller conveyor. The glass substrate 10 is sent from left to right in the figure with the left and right edges of its lower surface placed on the rollers of the conveyor 12. . In the middle of the conveyor 12, there is provided a small-diameter micro-rod bar 16 having a circular cross section, a large-diameter nip roller 18 opposing above, and a coating solution tank 20 into which almost the entire part except the upper part of the micro-rod bar 16 enters. Have been.
[0025]
Here, the micro rod bar 16 is formed by winding a thin metal wire having a diameter of about 100 μm in close contact with a surface of a metal rod having a circular cross section having a diameter of about 12 mm, and utilizing a capillary phenomenon caused by a groove between the metal wires. To apply a coating liquid, that is, a photoresist.
[0026]
As shown in FIGS. 2, 3 and 4, the coating liquid tank 20 has a liquid reservoir 22 which is long and shallow in a direction perpendicular to the horizontal direction of the substrate 10 in the horizontal direction. A new liquid is supplied to the liquid reservoir 22 from a liquid supply pipe (not shown), and a coating liquid is discharged from a liquid discharge port 26. The liquid supply pipe faces near the bottom surface near one end of the liquid reservoir 22, and the drain port 26 opens at the bottom near the other end. Therefore, the coating liquid is suitable for flowing in the liquid reservoir 22 in the longitudinal direction thereof to homogenize the liquid. The depth of the coating liquid is monitored by a liquid level sensor (not shown), and is constantly maintained.
[0027]
The micro rod bar 16 is held horizontally so that its upper part is exposed from the liquid. That is, bearing portions 30 and 32 having concave portions opened in a semi-circular shape are provided at both ends of the liquid reservoir portion 22, and between the bearing portions 30 and 32 and the caps 34 and 36 covered from above. The micro rod bar 16 is rotatably held. An intermediate portion of the micro rod bar 16 is supported by a backup member 38 from below.
[0028]
The backup member 38 is made of a hard synthetic resin having excellent slidability. A semicircular groove formed on the upper surface of the backup member 38 along the longitudinal direction comes into contact with the micro rod bar 16 from below, and the micro rod bar 16 This is to prevent deflection. The height of the backup member 38 can be finely adjusted from the lower surface of the coating solution tank 20 by a number of adjusting screws 40 arranged below the backup member 38.
[0029]
One end of the micro rod bar 16 (the end on the far side in FIG. 1) protrudes rearward from the coating liquid tank 20, and this protruding end is connected to an electric motor 44 by a detachable joint 42. The rotation of the electric motor 44 is controlled so that the feed speed of the glass substrate 10 is equal to that of the conveyor 12. The surface of the nip roller 18 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 18 and the micro rod bar 16.
[0030]
The micro rod bar 16 is formed as shown in FIGS. That is, it has a metal rod 100 substantially similar to the metal rod 1 described with reference to FIGS. 7 and 8, and a wire 102 closely wound around the application range L of the metal rod 100. The end faces 104, 104 of the metal rod 100 are formed with cutouts 106, 106 that open to both ends of the application range L and the end faces 104, 104, respectively.
[0031]
Both ends of the wire 102 are engaged in these notches 106, 106, and are fixed by solder 108 (only the right end is provided in FIG. 5). Grooves 110, 110 for guiding the wire 102 to these notches 106, 106 are formed near both ends of the application range L of the metal rod 100.
[0032]
Since the wire 102 is wound to a position sufficiently close to the end face 104, it is sufficient that the solder 108 is provided in a short range N from the end face 104. The range N can be か ら to ３ (that is, N = 1 to 2 mm) of the range M shown in FIG.
[0033]
For this reason, when cutting or polishing the outer diameter of the solder 108A so as to be equal to the outer diameter of the closely wound portion of the wire 102, "drip" on the outer peripheral surface of the solder 108 is reduced.
[0034]
Since the wire 102 is actually much thinner (about 100 μm in diameter) than the metal rod 100 (about 12 mm), the groove 110 for guiding the wire 102 to the notch 106 may be provided in a length to be wound several times to several tens times. However, it is preferable to make the groove 110 as short as possible, since the range N in which the solder 108 is provided can be made sufficiently short. In particular, it is more preferable that the wire 102 be sufficiently soldered in the notch 106 and the area of the solder appearing on the surface of the application range L be sufficiently small.
[0035]
If the wire 102 is engaged with the notch 106 and soldered to the notch 106 while pulling its end, the radius of curvature of the bent portion when the wire 102 is introduced into the notch 106 is sufficiently small. Can be fixed by soldering. Therefore, the amount by which the bent portion of the wire 102 projects from the outer diameter of the wire tightly wound portion becomes extremely small.
[0036]
As a result, when cutting or polishing the solder 108A, the wire 102 is shaved, and the wire 102 does not break or break at this portion. In addition, it is desirable to perform chamfering on the edge of the notch 106 that is continuous with the groove 110 to prevent the radius of curvature of the wire 102 from becoming too small.
[0037]
Next, the operation of this embodiment will be described. The glass substrate 10 is placed on the roller conveyor 12 with the surface of the pattern 46 facing down, and is sent from left to right in FIG. Then, the glass substrate 10 enters between the micro rod bar 16 and the nip roller 18. Since the application liquid in the liquid reservoir 22 adheres to the surface of the micro rod bar 16 due to its rotation, the application liquid is applied to the lower surface of the glass substrate 10 with the rotation of the micro rod bar 16.
[0038]
At both edges of the application range L of the micro rod bar 16, as shown in FIGS. 5 and 6, the soldering range N of the solder 108 is sufficiently short, so that the outer diameter does not change much and "drip" on the outer peripheral surface is small. Further, since the wire 102 can be wound evenly on the outer peripheral surface of the coating range L without any trace such as spot welding, when the micro rod bar 16 is used, the coating surface (lower surface) of the glass substrate 10 is coated. Less unevenness.
[0039]
On the other hand, even when the micro rod bar 16 is subjected to ultrasonic cleaning, the amount of solder used is remarkably reduced as compared with the methods shown in FIGS. This can reduce the risk of peeling off, and can prevent contamination and quality deterioration of the application surface due to the peeling solder.
[0040]
In the above embodiment, the solder 108 is provided on the surface of the application range L. However, it is preferable that the amount of the solder 108 appearing in the application range L is minimized and the solder 108 is firmly fixed in the notch 106 as much as possible. For fixing the terminal of the wire 102, an adhesive or the like may be used instead of the solder 108.
[0041]
In particular, spot fixing or the like can be used when fixing inside the notch 106 or on the terminal side from the notch. Also, the diameter and the application range L of the metal rod 100 and the wire 102 used in the above embodiment are of course only examples.
[0042]
【The invention's effect】
According to the first aspect of the present invention, as described above, the notch facing the application range and the end surface is provided on the end face which is the outer edge of the application range of the metal rod, and the end of the wire is guided and fixed to the notch. Thus, the wire can be wound to a position sufficiently close to both edges of the application range. For this reason, the amount of solder to be applied is remarkably reduced, and a decrease in diameter near both ends of the coating range, that is, a "drip" on the surface is reduced, which is suitable for making the coating thickness uniform.
[0043]
Also, since the amount of solder used at the wire ends is reduced and the solder area that appears on the applied surface is small, the solder is less likely to peel off even if the micro rod bar is subjected to ultrasonic cleaning. There is no possibility of inviting. Furthermore, since there is no non-uniform trace such as spot welding left on the surface of the coating area where the wire is wound, no coating unevenness occurs on the coating surface, and the processing of the wire end is simplified.
[0044]
Here, in order to fix the wire end to the notch, solder can be applied to a predetermined range of both edges of the application range, and this portion can be processed to the outer diameter of the wire tightly wound portion (claim 2). In this case, it is possible to reliably prevent the wire from coming off the end face and collapsing. If a groove is formed in the metal rod to guide the wire to the notch, the wire is less likely to come off from the end face, and the soldering range (N) can be further reduced (claim 3).
[Brief description of the drawings]
FIG. 1 is an overall layout view of a hard substrate coating apparatus using one embodiment of the present invention. FIG. 2 is a sectional view of the coating apparatus. FIG. 3 is a front sectional view of the coating apparatus. FIG. FIG. 5 is a view showing a terminal structure of the micro rod bar according to the present invention. FIG. 6 is a right side view of the micro rod bar. FIG. 7 is a view showing a conventional wire terminal structure. Cross-sectional right side view [Explanation of reference numerals]
Reference Signs List 10 Glass substrate 12 as hard substrate 12 Roller conveyor 14 Gieser 16 Micro rod bar 18 Nip roller 22 Coating liquid layer 100 Metal rod 102 Metal wire 104 End face 106 Notch 108 Solder 110 Groove L Application range N Solder placement range

Claims (3)

The lower portion is immersed in a coating liquid tank, and the hard substrate is sandwiched between a nip roller and a nip roller disposed above the tank so as to feed the coating liquid. A metal rod having a small-diameter portion formed on both sides in the axial direction of the application range via an end face, and a thin metal wire densely wound around the application range of the metal rod; A micro rod bar for a hard substrate coating apparatus, wherein a pair of cutouts facing the end face and the application range are formed at both ends, and both ends of the wire are engaged with and fixed to these cutouts. 2. The micro-rod bar according to claim 1, wherein solder is applied to the outer periphery of the wire within a predetermined range of both edges of the application area, and the outer periphery of the applied solder is processed to an outer dimension of a tightly wound portion of the wire. The micro rod bar of the hard substrate coating apparatus according to claim 1 or 2, wherein grooves are formed at both edges of the application range of the metal rod to engage the wire and guide the wire to the notch.

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