JP4325084B2 - Coating method and color filter manufacturing method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to, for example, a color filter for a color liquid crystal display, a plasma display, an optical filter, a printed circuit board, an integrated circuit, a sheet-like material such as paper, in addition to a manufacturing field in which coating is applied to a sheet material A coating method for forming a coating film while discharging a coating liquid onto the surface of a member to be coated, such as a glass substrate of a color filter, and the like.Used itManufacturing method of color filterInRelated.
[0002]
[Prior art]
A color filter for a color liquid crystal display has a fine lattice pattern of three primary colors on a glass substrate. Such a lattice pattern forms red (R) after forming a black coating film on the glass substrate. Blue (B) and green (G) coating films are sequentially formed, and thereby, the glass substrate is obtained by coating the three primary colors separately.
[0003]
Therefore, for the production of a color filter, a forming process is required in which black, red, blue, and green coating liquids are sequentially applied onto a glass substrate to form the coating film. In the process of forming this type of coating film, a coating device is usually used, and spinners, bar coaters or roll coaters have been used in many cases. However, the consumption of coating liquid is reduced and the quality of the coating film is reduced. Recently, a die coater has been used for the purpose of improvement.
[0004]
An example of this type of die coater is disclosed in JP-A-6-339656. This known die coater has a reciprocating stage and a slit die which is an applicator having a downward discharge port, and the upper surface of the stage is configured as a suction surface. Therefore, the glass substrate on which the coating film is to be formed can be adsorbed and held on the stage. After the glass substrate is adsorbed and held on the stage, when the glass substrate moves directly under the coating head with the stage, the coating liquid is discharged from the discharge port of the slit die to continuously apply the coating film on the glass substrate. Can be formed.
[0005]
[Problems to be solved by the invention]
In the above-described die coater, application is performed with a clearance, which is a gap between the tip of the slit die and the glass substrate adsorbed on the stage, usually being about 80 to 300 μm. However, when a large number of sheets are continuously applied in the actual production process, a foreign substance may be sandwiched between the glass substrate and the stage and a part of the substrate may be raised, or the foreign substance may adhere to the glass substrate surface. If the bulges on the substrate and foreign matter on the substrate surface are larger than the clearance, they will contact the tip of the slit die, and in extreme cases, the die tip and the glass substrate will be damaged, and subsequent coating Will be forced to cancel.
[0006]
There are not many known examples corresponding to such protruding portions on the surface of the substrate. However, in Japanese Patent Laid-Open No. 12-24571, a raised portion of the substrate caused by biting a foreign object into the plate-like member arranged in front of the slit die. In addition, when the foreign matter on the surface of the substrate collides with the accelerometer, the movement of the substrate is forcibly stopped when the raised portion of the substrate or the foreign matter is detected. However, if the movement of the substrate is forcibly stopped during coating, the operation time of the apparatus is reduced by the time required for the restoration, resulting in a production loss.
[0007]
In addition, when detecting a raised part of a substrate or a foreign object, a fixed plate member, which is a kind of detector, and a raised part of the substrate or a foreign object collide with each other because of a large impact force. There is a high possibility of waking up. If the board is damaged, it can no longer be used as a product, and if the plate is damaged, it must be replaced. It takes a lot of time to remove and clean the damaged board, and replace the plate. Incurs cost increase due to excessive loss. To make matters worse, there is a possibility that damage will scatter and remain in the vicinity, leading to foreign objects that cause coating defects and foreign substances that cause subsequent substrate bulges, causing secondary damage. come.
[0008]
Therefore, it is desirable that the means for detecting the protrusion of the substrate is a non-contact type, but the laser beam as described in Japanese Patent Application Laid-Open No. 12-24571 is scanned over the substrate to remove foreign matter by the interference waveform. With the detecting means, it takes time to determine the foreign matter and the unevenness, and when applying at high speed, the time is not in time, and it is not practical.
[0009]
  This invention was made based on the above-mentioned circumstances, and its intended place is:
(1) When detecting a raised part of the substrate or foreign matter on the surface of the substrate, the movement of the substrate is forcibly stopped, causing no loss of operating time or production. Avoiding contact with the
(2) The detection of foreign matters on the raised portion of the substrate and the substrate surface should be performed without damaging the substrate and the detection member.
A coating method capable of reducing the cost by improving the productivity and operating rate of the die coaterThatMethod of manufacturing color filter using methodTheIt is to provide.
[0010]
[Means for Solving the Problems]
  The above objective is accomplished by the present invention.
  In the coating method according to the present invention, the discharge port of the applicator is brought close to the member to be coated up to a certain gap, and the coating liquid is discharged from the discharge port of the applicator to the member to be coated. In a coating method in which one side is moved relatively to form a coating film on the coated member, CoveredForeign matter on the surface of the coated member or on the coated memberofdetectionIrradiating a laser beam in the longitudinal direction of the applicator, and performing based on the length of the one that blocks the laser beam,The applicator is withdrawn before the raised portion or foreign matter contacts the applicator.At the same time, the relative movement of the applicator and the member to be applied is stopped, and the discharge of the coating liquid from the applicator is stopped to stop the application.It is characterized by that.
[0011]
  In this coating method, as will be described later in the embodiments, it is preferable that after the coating is interrupted, the member to be coated is sent to the regeneration process or is returned to the process before coating to resume the coating.
[0014]
The method for producing a color filter according to the present invention comprises a method characterized in that a color filter is produced using the coating method as described above.
[0016]
  Application method of the present inventionInAccording to the above, it is possible to detect the raised part of the substrate and the foreign matter on the surface, and retract the applicator without stopping the movement of the substrate and the applicator to avoid the collision. It is possible to protect the vessel.
[0017]
Further, the detection of the foreign matter on the raised portion of the substrate or the surface is performed by means that does not contact the substrate or the foreign matter, or the operation for avoiding or mitigating the contact between the detection member and the foreign matter on the raised portion of the substrate or the surface. Therefore, it is possible to prevent damage to the substrate and the detection member, and to prevent the loss of operation time caused by taking out the damaged substrate, cleaning, and replacement of the detection member in addition to the damage of the substrate and the detection member. Can do. Furthermore, secondary defects such as a coating defect due to scattered scattered objects and a new substrate bulge caused by biting damaged scattered objects can be avoided.
[0018]
  Manufacturing method of color filter of the present inventionInAccording to the above excellent coating methodsoBecause color filters are manufactured, avoid contact between the applicator and the raised parts of the substrate or on the surface, eliminate operating time and loss of production, and manufacture color filters with high productivity. Can do.
[0019]
[Form of the present invention]
  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
  FIG. 1 shows an embodiment of the present invention.CanFIG. 2 is a configuration diagram around the stage 6, the slit die 40 and the coating liquid supply device of FIG. 1.
[0020]
Referring to FIG. 1, there is shown a coating apparatus so-called die coater 1 applied to the production of a color filter for a color liquid crystal display. The die coater includes a base 2, and a pair of guide groove rails 4 are provided on the base 2. Above these guide groove rails 4, a stage 6 is disposed that can reciprocate horizontally on the guide groove rails 4 via a pair of slide legs 8. The stage 6 holds the substrate A. For this reason, a suction hole (not shown) is provided on the upper surface of the stage 6 so as to act as a suction surface.
[0021]
A feed screw mechanism shown in FIG. 2 and a casing 12 incorporating the same are arranged between the pair of guide groove rails 4, and the casing 12 extends along the guide groove rails 4. As shown in FIG. 2, the feed screw mechanism is configured such that a feed screw 14 formed of a ball screw is screwed into a nut-like connector 16 fixed to the lower surface of the stage 6, and further extends through the connector 16. Both end portions thereof are rotatably supported by a bearing (not shown), and an AC servo motor 18 is connected to one end thereof. An opening is formed on the upper surface of the casing 12 so as not to hinder the movement of the connector 16, but the opening is omitted in FIG. 1.
[0022]
Further, referring to FIG. 1, a die support 24 having an inverted L shape is disposed at substantially the center of the upper surface of the base 2. The tip of the die support 24 is positioned above the reciprocating path of the stage 6, and an elevating mechanism 26 is attached to the tip. The elevating mechanism 26 includes an elevating bracket (not shown) that can be raised and lowered, and the elevating bracket is attached to a pair of guide rods in the casing 28 so as to be raised and lowered. Further, a feed screw (not shown) made of a ball screw is also disposed between the guide rods in the casing 28 so as to be rotatable, and a lifting bracket is attached to the feed screw via a nut-type connector. Are connected. An AC servomotor 30 is connected to the upper end of the feed screw, and this AC servomotor 30 is attached to the upper surface of the casing 28.
[0023]
A die holder 32 is attached to the elevating bracket via a support shaft (not shown). The die holder 32 has a U-shape and extends horizontally between the rails 4 above the pair of guide groove rails 4. ing. The support shaft of the die holder 32 is rotatably supported in the lifting bracket, so that the die holder 32 can rotate in the vertical plane together with the support shaft.
[0024]
A horizontal bar 36 is also fixed to the lifting bracket above the die holder 32, and the horizontal bar 36 extends along the die holder 32. Electromagnetically operated linear actuators 38 are respectively attached to both ends of the horizontal bar 36. These linear actuators 38 have telescopic rods protruding from the lower surface of the horizontal bar 36, and these telescopic rods are in contact with both ends of the die holder 32.
[0025]
A slit die 40 as an applicator is attached in the die holder 32. As apparent from FIG. 1, the slit die 40 extends horizontally in the direction orthogonal to the reciprocating direction of the stage 6, that is, in the longitudinal direction of the die holder 32, and is supported by the die holder 32 at both ends thereof.
[0026]
The slit die 40 has a long block-shaped front lip 66 and rear lip 60 as schematically shown in FIG. The lips 66 and 60 are attached to the front and rear as viewed in the reciprocating direction of the stage 6 and are integrally coupled to each other by a plurality of connecting bolts (not shown). By bonding both lips 66 and 60 through a shim (not shown), a discharge port 74 for discharging the coating liquid is formed on the discharge surface 72 which is the lower surface of the slit die 40. When the coating liquid is discharged from the discharge port 74, a coating liquid bead C is formed between the discharge surface 72 and the substrate A.
[0027]
A manifold 62 is formed inside the slit die 40 at a central portion thereof, and the manifold 62 extends horizontally in the longitudinal direction of the slit die 40, that is, in the direction orthogonal to the reciprocating direction of the stage 6. The manifold 62 is always connected to the above-described application liquid supply hose 42 via an internal passage (not shown), whereby the manifold 62 can be supplied with the application liquid.
[0028]
A slit 64 having an upper end communicating with the manifold 62 is formed inside the slit die 40, and a lower end of the slit 64 is opened at the discharge surface 72 to form a discharge port 74. As described above, a gap is secured in the slit 64 by sandwiching a shim (not shown) between the front lip 66 and the rear lip 60.
[0029]
As shown in FIG. 2, a coating solution supply hose 42 extends from the slit die 40, and the tip of the supply hose 42 is connected to the supply port of the electromagnetic switching valve 46 of the syringe pump 44. . A suction hose 48 extends from the suction port of the electromagnetic switching valve 46, and the tip of the suction hose 48 is inserted into the tank 50. Note that a coating liquid 70 is stored in the tank 50.
[0030]
The pump part of the syringe pump 44 takes the form of a piston-type pump, and is composed of a syringe 80 that stores the coating liquid and a piston 52 that pushes out the stored coating liquid or conversely sucks it in order to store the coating liquid. Is done. By the switching operation of the electromagnetic switching valve 46, the coating liquid in the syringe 80 can be fluidly connected to one of the supply hose 42 and the suction hose 48. The linear switching mechanisms (not shown) of the electromagnetic switching valve 46 and the piston 52 are electrically connected to the computer 54. Upon receiving a control signal from the computer 54, the switching direction of the electromagnetic switching valve 46 and the piston 52 are connected. The moving speed and moving position of the are controlled.
[0031]
Further, a sequencer 56 is also electrically connected to the computer 54 in order to control the operation of the syringe pump 44 described above. The sequencer 56 performs sequence control of the operations of the AC servomotor 18 of the feed screw 14 on the stage 6 side, the AC servomotor 30 on the lifting mechanism 26 side, and the linear actuator 38. For the sequence control, the sequencer 56 is used. Are input with signals indicating the operating state of the AC servomotors 18 and 30, signals from the position sensor 58 that detects the moving position of the stage 6, signals from a sensor (not shown) that detects the operating state of the slit die 40, and the like. On the other hand, the sequencer 56 outputs a signal indicating a sequence operation to the computer 54. Instead of using the position sensor 58, it is also possible to incorporate an encoder into the AC servomotor 18 and detect the position of the stage 6 with the sequencer 56 based on the pulse signal output from the encoder. Further, it is possible to incorporate control by the computer 54 into the sequencer 56.
[0032]
Referring again to FIG. 1, a sensor column 20 having a reverse inverted L shape is disposed on the upper surface of the base 2 on the front side of the die support 24. The tip of the sensor column 20 is positioned above the reciprocating path of the suction plate 6, and a thickness sensor 22 is attached to the tip of the sensor column 20 via a bracket 21. The thickness sensor 22 can measure the thickness of the substrate A placed on the stage 6.
[0033]
Further, the die coater 1 is provided with a detection system A100 for detecting foreign matters adhering to the raised portion of the substrate A or the surface of the substrate A. This detection system A100 is a pair of a laser irradiation unit 104 that irradiates a vertically long laser light beam 110 and a laser light receiving unit 106 that receives the laser light beam 110 from the laser irradiation unit 104. It is attached to the side cover 10 of the coater 1 via a bracket 102 of the mold. The laser light receiving unit 106 is electrically connected to the length calculator 108. The laser irradiation unit 104 and the laser light receiving unit 106 function as a pair. The laser beam 110 is blocked by detecting the length in the vertical direction and is converted into an actual length by the length calculator 108. Therefore, it is used as a length measuring instrument. As shown in FIG. 2, the length calculator 108 is electrically connected to the computer 54, and the operation of the die coater 1 can be controlled by data sent from the length calculator 108.
[0034]
A measurement system using the detection system A100 and a collision avoidance system for the slit die 40 using the measurement system will be described. First, when the stage 6 holding the substrate A by suction blocks the laser beam 110 irradiated from the laser irradiation unit 104, the laser light receiving unit 106 detects the length in the vertical direction of L1. When the laser beam is blocked by the stage 6 without placing the substrate A, the length L0 is detected, so that the substrate thickness t can be calculated from L1-L0. This substrate thickness t is measured by the thickness sensor 22. Match what you do. Here, foreign matter is caught between the adsorption surface of the substrate A and the stage 6 and the substrate is raised at that portion, or the foreign matter adheres on the surface of the substrate A, and the laser irradiation unit 104 irradiates the substrate. When the laser beam is blocked, the light receiving unit 106 detects the length L2. Since L2 is larger than the sum t + L0 = LT of the thickness t of the substrate A measured by the thickness sensor 22 and the length L0 representing the position of the substrate suction surface of the stage 6, the raised portion of the substrate A from L2−LT. Alternatively, it is possible to know the length of the foreign matter in the vertical direction. When L2-LT becomes larger than the allowable value determined from the clearance between the slit die 40 and the substrate A, the lifting mechanism 26 is operated to raise the slit die 40 to contact the raised portion of the substrate A and foreign matter. Prevent in advance.
[0035]
Next, a coating method using this coating apparatus will be described.
First, the origin of each operating part in the die coater 1 is returned, and the stage 6 and the slit die 40 are moved to the standby position. At this time, the coating liquid 70 is already filled from the tank 50 to the slit die 40, and the so-called air bleeding operation of discharging the coating liquid with the die facing upward to discharge the residual air inside the die has already been completed. At the same time, the syringe pump 44 also sucks and stores a predetermined amount of the coating liquid from the tank 50 and stands by in a state where the coating liquid can be discharged at any time. Then, lift pins (not shown) rise on the surface of the stage 6, and when the substrate A is placed from a loader (not shown), the lift pins are lowered to place the substrate A on the upper surface of the stage and suck the substrate A. Simultaneously with the adsorption of the substrate A, the thickness sensor 22 measures the thickness of the substrate A, and based on this thickness, the clearance between the substrate A and the discharge surface 72 of the slit die 40 becomes a value given in advance. The slit die 40 is lowered. Then, the stage 6 is driven at the coating speed and moved toward the slit die 40. During this movement, the substrate A blocks the laser light beam 110 emitted from the laser irradiation unit 104 of the detection system A100, and the length detected by the laser light receiving unit 106 is the thickness of the substrate measured by the thickness sensor 22 on the stage 6. Is determined to be smaller than the length obtained by blocking the laser beam 110 and the allowable value added, the movement is continued as it is. Then, when the coating start portion of the substrate A is just below the discharge port 74 of the slit die 40, a command is issued from the computer 54 to the syringe pump 44 to start the operation of the syringe pump 44 and The coating liquid is discharged from the discharge port 74, and a coating liquid bead C is formed between the discharge surface 72 of the slit die 40 and the substrate A, and application to the substrate A is started. When the application end position of the substrate A comes directly below the discharge port 74 of the slit die 40, a stop command is issued from the computer 54 to the syringe pump 44 to stop the discharge of the coating liquid from the slit die 40, and the slit The die 40 is raised to completely reach the coating liquid bead C.
[0036]
During these operations, the stage 6 continues to move and stops when the substrate A reaches the end position. In the above process, the substrate A blocks the laser beam 110 irradiated from the laser irradiation unit 104 of the detection system A100, and the length detected by the laser light receiving unit 106 is normally measured on the stage 6 by the thickness sensor 22. If it is determined that the thickness obtained by properly placing a substrate having a thickness and blocking the laser beam 110 is greater than the allowable value plus the allowable value, Since it is determined that foreign matter is attached, in any case, the elevating mechanism 26 is immediately driven to raise the slit die 40, while the stage 6 is moved as it is to the end point position. If application is in progress, it is preferable that the operation of the syringe pump 44 be forcibly stopped at the same time or before the slit die 40 is raised, and the stage 6 is moved to the end point position as it is. This is because if the operation of the syringe pump 44 is stopped after the slit die 40 is raised, useless coating liquid is discharged during the rise, leading to an increase in cost.
[0037]
When the substrate A stops at the end position regardless of whether the coating is normally performed or not, the suction is released and the lift pins are raised to lift the substrate A. At this time, the substrate A is transferred to the next step by an unloader (not shown). Thereafter, the stage 6 lowers the lift pins and returns to the original position. Then, waiting for the next substrate A to come, the same operation is repeated.
[0038]
In addition, it is detected that abnormality is detected by detection system A100, and application | coating is not performed or application | coating was interrupted on the way, and it is abnormal in a subsequent application | coating inspection process. Those that have been applied halfway are sent to the regeneration process, and all the applied material is peeled off to become only the glass substrate and reused. In addition, after the foreign matter is removed, the product that has not been applied is returned to the step before the application, and the production is restarted from the application point.
[0039]
As described above, when the moving speed of the substrate A is high, the time for blocking the laser beam 110 irradiated from the laser irradiation unit 104 is too short depending on the shape of the foreign matter adhering to the raised portion or the surface of the substrate A, and the laser Detection may be missed by the light receiving unit 106. In this case, the laser beam 110 has a certain length in the traveling direction of the substrate A so that it can be detected on the surface, or a plurality of laser irradiation units 104 are arranged to improve the detection probability. Is preferred.
[0040]
Next, an embodiment of another detection system that detects foreign matter adhering to the raised portion or the surface of the substrate A before applying the applicator close by using an elevating mechanism will be described.
[0041]
FIG. 3 is a front view showing the detection system B200, and FIG. 4 is a plan view showing a generation state of a light stripe pattern 204 generated when the detection system B200 is used. The detection system B200 irradiates the substrate A with several rows of slit light 226 extending in the longitudinal direction of the slit die 40, and causes the substrate A to extend in the substrate width direction (direction perpendicular to the traveling direction of the substrate A) 204. Is formed of a slit light source 210 that generates light, a camera 202 that detects a stripe pattern 204 of light on the substrate A, and an image processing device 220 that performs image processing on an image captured by the camera 202. The slit light source 210 includes a planar light source 218, and slit plates 212 in which slits 216 extending in the longitudinal direction of the slit die 40 and light shielding portions 214 are alternately arranged. Here, the light stripe pattern 204 on the substrate A is a straight stripe 206 when the surface of the substrate A is straight and has no irregularities. On the other hand, when a foreign object is sandwiched between the substrate A and the stage 6 to form a raised portion 222 of the substrate, or a foreign object 224 is adhered on the surface of the substrate A, and the surface of the substrate A is uneven, Distorted stripes 208A and 208B are formed, and the degree of distortion is proportional to the size of the unevenness. Therefore, when the light stripe pattern 204 is captured by the camera 202 and analyzed by the image processing device 220, and the distortion amount of the distorted stripe 208 exceeds a certain allowable value, the raised portion 222 caused by the foreign matter biting into the substrate A, Since it can be determined that there are foreign substances 224 adhering to the surface of the substrate A and they are larger than the clearance set between the slit die 40 and the substrate A, it is possible to detect abnormality of the substrate A in which the slit die 40 should be retracted. Can be used.
[0042]
Since the detection system A100 and the detection system B200 described above detect the raised portion and foreign matter of the substrate A in a non-contact manner, the substrate A to be detected can be prevented from being damaged at all.
[0043]
Next, a description will be given of an embodiment of a system for detecting a raised portion or a foreign substance from an operation of avoiding or mitigating the raised portion of the substrate A.
5 is a front view of the detection system C250, and FIG. 6 is a side view of FIG.
[0044]
The detection system C250 has substantially the same height as the discharge surface 72 of the slit die 40 and extends in parallel with the wire 254 in the longitudinal direction of the slit die 40, and supports both ends of the wire 254 to support both ends of the slit die 40 in the longitudinal direction. It is comprised from the displacement meter 256 which detects a vibration of a pair of brackets 252A and 252B attached to the wire 254. The displacement meter 256 is attached to the bracket 252A.
[0045]
Next, the detection operation by the detection system C will be described. First, when a raised portion of the substrate A or a foreign matter on the surface comes into contact with the wire 254, a foreign matter having a weak adhesive force is repelled by the wire 254. If not, the wire vibrates in a string. By detecting the vibration with a displacement meter, it is possible to detect the presence of a raised portion or a foreign object.
[0046]
Although the raised portion and the foreign matter come into contact with the wire, the wire moves away from the wire, so that damage to the raised substrate can be prevented. The displacement meter 256 is not limited to the illustrated mounting direction, and may be installed in any mounting direction as long as vibration can be detected effectively. Further, the displacement meter 256 may be used as a microphone to detect the natural vibration sound of the wire 254.
[0047]
In the above description, the installation position of the wire 254 is substantially the same height as the discharge surface 72 of the slit die 40, but it may be installed anywhere between the discharge surface 72 of the slit die 40 and the substrate A. It is preferable that the clearance be between 30% and 100% of the clearance between the discharge surface 72 of the slit die 40 and the substrate A.
[0048]
Next, FIG. 7 is a front view of an embodiment of a detection system D300 which is another detection system, and FIG. 8 is a plan view of FIG.
[0049]
The detection system D300 holds the detection body 302 extending in the longitudinal direction of the slit die 40, the holding body 304 that can move only in the vertical direction, and extends in the longitudinal direction of the slit die 40. FIG. 7 shows a lifting bolt 308 for moving the detection body 302 in two directions on both sides in the longitudinal direction of the slit die 40, a fixing plate 306 for holding the lifting bolt 308 and connecting it to the holding body 304, and the holding body 304. A rotating shaft 316 that holds the rotating shaft 316 in a rotatable manner, a bracket 310 that holds the rotating shaft 316 and is connected to both longitudinal sides of the slit die 40, and a counterclockwise rotation around the rotating shaft 316 of the holding body 304, that is, a detection body A counter 318 that restricts rotation to the 302 side, and a counter attached to the holding body 304 that adjusts the weight applied to the detection body 302 side Weight 320, the holding member 304 detects that the increase by the rotation of the around the rotation shaft 316, proximity sensor 314 which is mounted via a sensor bracket 312 to the bracket 310, and a.
[0050]
Next, the detection operation by the detection system D300 will be described.
First, the position of the detection surface 301, which is the lowermost end surface of the detection body 302, is adjusted using the two lifting bolts 308 so that the detection surface 301 has substantially the same height as the discharge surface 72 of the slit die 40. This adjustment operation is performed in a state where the holding body 304 is in contact with the stopper 318. As a result, the detection surface 301 of the detection body 302 is not positioned below the discharge surface 72 of the slit die 40.
[0051]
Next, when the substrate A approaches the detection body 302, if there is no raised portion or foreign matter larger than a predetermined size on the substrate A, nothing will contact the detection surface 301, and nothing will contact the slit die 40 as well. do not do. If the substrate A has a raised portion or foreign matter having a predetermined size or more, the detection surface 301 is conversely contacted, so that the detection body 302 and the holding body 304 holding the detection body 302 are rotated around the rotation axis 316. It moves upward by rotating clockwise. This movement can be detected by the proximity sensor 314, so that a raised portion of the substrate A or a foreign object can be detected.
[0052]
How much the detection body 302 moves upward can be arbitrarily set by the proximity sensor 314, but is preferably 1 to 100 μm. The magnitude of the contact force between the detection surface 301 and the raised portion of the substrate or the foreign matter can be adjusted by a counterweight, but the contact force between the two is preferably 0.1 to 1 kg, more preferably 1 to 200 g. . By reducing this contact force, it is possible to prevent damage to the substrate or the detection surface even if the detection surface 301 is in contact with the substrate or foreign matter.
[0053]
Furthermore, although the lowest position of the detection surface 301 of the detection body 302 is substantially the same as the discharge surface 72 of the slit die 40 in the above description, it is installed anywhere between the discharge surface 72 of the slit die 40 and the substrate A. In other words, it is preferable that the distance between the discharge surface 72 of the slit die 40 and the substrate A is 30% to 100% of the clearance from the substrate.
[0054]
FIG. 9 is a front view showing another embodiment of the detection system D. FIG. Here, in the detection system D described above, only the detection body 302 is changed to a floating detection body 340 that blows out air from a slit 342 extending in the longitudinal direction of the slit die 40. When a raised portion or foreign matter of a substrate of a predetermined size or more approaches the floating detector 340, the floating detector 340 returns to the holding body 304 by tracing the shape of the raised portion 324 of the substrate or the foreign matter by the action of air. The proximity sensor 314 can determine whether there is a raised portion or a foreign object. According to this means, the lower surface 344 of the floating detector 340 is not in direct contact with the substrate A and foreign matter, and air is always present, so that the substrate A and the floating detector 340 are not reliably damaged. In addition, it is possible to expect an effect that foreign matter having a small adhesion force is blown off by the air discharged from the floating detector 340. Further, suction air may be provided before and after the floating detector 340 so that the air discharged from the floating detector 340 is not scattered around, and the discharged air may be collected. Although the air wind speed discharged from the discharge port 342 may be determined from the rising behavior of the floating detector 340 with respect to the substrate bulge and foreign matter, it is preferably 0.1 to 20 m / s, more preferably 0.5 to 5 m / s. s.
[0055]
Next, FIG. 10 is a front view of an embodiment of a detection system E400 which is another detection system, and FIG. 11 is a plan view of FIG.
[0056]
The detection system E400 is connected to a floating detector 404 that discharges air from a slit 402 extending in the longitudinal direction of the slit die 40, and a pair of left and right rails 406 that extend in the vertical direction, connected to both left and right ends of the floating detector 404 in the longitudinal direction. , Two left and right guide plates 408 that hold and guide only movable in the vertical direction, two L-shaped brackets 416 to which each rail 406 is attached, two brackets 418 that connect the L-shaped bracket 416 to the slit die 40, and floating The rise of the detection body 404 is detected, and the lower limit position of the proximity sensor 412 and the floating detection body 404 disposed on each of the two L-shaped brackets 416 is slit by contact with the block 422 attached to the floating detection body 404. U-shaped stopper 4 that is restricted at two locations in the longitudinal direction of the die 40 Composed of lifting bolts 414 for moving and guiding the 0,2 one stopper 420 in the vertical direction with respect to the L-bracket 416.
[0057]
The detection operation by the detection system E400 is as follows.
First, the left and right lifting bolts 414 are moved to adjust the position of the stopper 420 so that the bottom surface 426 which is the lowermost end surface of the floating detector 404 is substantially the same height as the discharge surface 72 of the slit die 40. . As a result, the bottom surface 426 is not positioned below the discharge surface 72 of the slit die 40.
[0058]
Next, air is discharged from the discharge port 402 of the floating detector 404. Here, when the substrate A approaches the floating detector 404, the bottom surface 426 of the floating detector 404 does not rise more than the waviness of the substrate unless the substrate A has a raised portion or foreign matter. Since the rising amount due to the wave of the substrate is much smaller than the allowable value determined so that the slit die 40 does not contact the raised portion of the substrate or foreign matter, the proximity sensor 412 does not react. Next, when the substrate A has a raised portion or a foreign object having a predetermined size or more, the bottom surface 426 rides on it through the air, so that the floating detector 404 rises greatly and exceeds the allowable value, and the proximity sensor 412 Thus, it is possible to detect the presence of a raised portion of the substrate A and foreign matter.
[0059]
According to this means, the floating detector 404 does not come into direct contact with the substrate or foreign matter, so that the substrate or the floating detector is not reliably damaged. In addition, it can be expected that foreign matter having a small adhesion force is blown off by the air discharged from the floating detector 404. Further, suction air may be provided before and after the floating detector 404 so as to collect the discharged air so that the air discharged from the floating detector 404 does not scatter around. The air wind speed discharged from the discharge port 402 may be determined from the rising behavior of the floating detector 404 with respect to the substrate bulge and foreign matter, but is preferably 0.1 to 20 m / s, more preferably 0.5 to 5 m / s. s.
[0060]
To what extent the floating detector 404 moves upward can be detected by the proximity sensor 412, the allowable value may be set arbitrarily, but preferably 5 to 500 μm, in order to distinguish it from the waviness of the substrate, More preferably, it is 20-100 micrometers.
[0061]
Furthermore, although the lowest position of the bottom surface 426 is substantially the same as the discharge surface 72 of the slit die 40 in the above description, it may be installed anywhere between the discharge surface 72 of the slit die 40 and the substrate A. The clearance between the discharge surface 72 of the slit die 40 and the substrate A is preferably 50% to 100%.
[0062]
The present invention described above can be applied not only to a single sheet such as a glass substrate, but also to a continuous sheet-like material such as a film, a metal sheet such as aluminum or iron, or a paper sheet by a slit die. FIG. 12 is a schematic side view showing an embodiment when the present invention is applied when a sheet-like material is applied with a slit die.
[0063]
In FIG. 12, the sheet 504 is held by the backup roll 500 and continuously travels in the direction of the arrow at a constant speed. The slit die 502 is disposed at a position away from the sheet 504 on the backup roll 500 by a clearance, and can be moved close to or away from the sheet 504 freely in the normal direction of the backup roll 500 by the lifting mechanism 510. . A coating liquid is sent from the tank 508 to the slit die 502 by the pump 506, and is discharged from the slit die 502 to the sheet 504 on the backup roll 500 to be a coating film 516. Further, a laser irradiation part 512 (front side in the figure) and a laser light receiving part 513 (back side in the figure) are arranged so as to sandwich the longitudinal direction of the backup roll 500. A laser beam that is long in the normal direction of the backup roll is emitted from the laser irradiation unit 512 toward the laser light receiving unit 513. When the foreign material 514 on the sheet 504 blocks the laser beam, the size of the foreign material is detected from the length of the laser beam and the clearance is between the slit die 502 and the sheet 504 on the backup roll 500. If the size is larger, the foreign matter 514 comes into contact with the slit die 502. Therefore, when the size of the foreign matter is equal to or larger than a predetermined allowable value, the slit die 502 is moved and retracted in the direction away from the sheet 504 by the lifting mechanism 510. .
[0064]
Note that the detection system of the laser irradiation unit 512 and the laser light receiving unit 513 can detect the size of the sheet 504 even when the foreign material is interposed between the backup roll 500 and the sheet 504. Further, the detection systems B, C, D, and E shown as single sheets such as a glass substrate are also detected on the backup roll 500 by detecting foreign matter on a continuous sheet-like material as in the present embodiment or by biting foreign matter. This can be applied to the detection of the protrusion of the sheet 504.
[0065]
Furthermore, the detection system for detecting foreign matters and raised portions on the sheet 504 is not only on the backup roll 500 where slit die coating is performed, but also on other guide rolls or in a free span section between rolls. You may arrange. Moreover, it is also possible to detect the part which joins a sheet | seat with a detection system.
[0066]
The coating liquid to which the present invention can be applied is not particularly limited, but has a viscosity of 1 cps to 100,000 cps, desirably 10 cps to 50,000 cps. As a member to be coated, in addition to glass, a sheet material such as a metal plate such as aluminum, a ceramic plate, a silicon wafer, or a sheet material such as a film, an aluminum plate, an iron plate, or paper may be used. Further, the coating conditions to be used include a clearance of 40 to 500 μm, more preferably 80 to 300 μm, a coating speed of 0.1 m / min to 200 m / min, more preferably 0.5 m / min to 10 m / min, and a die lip. The gap is 50 to 1000 μm, more preferably 100 to 600 μm, and the coating thickness is 5 to 400 μm, more preferably 20 to 250 μm.
[0067]
  In addition, when a protruding part of the substrate or foreign matter exceeding the allowable value was detected, the slit die was retracted or the discharge of the coating liquid from the coating liquid was stopped. If reduction is not an issue, you can do it.Therefore, in the present invention, when a raised portion or foreign matter on the substrate exceeding the allowable value is detected, the applicator is retracted before the raised portion or foreign matter comes into contact with the applicator, and the applicator and the member to be coated are removed. The relative movement was stopped, and the application was interrupted by stopping the discharge of the coating liquid from the applicator.The stage may be stopped every time an abnormally raised portion of the substrate or a foreign object is detected, or after several abnormal states are continuously detected.
[0068]
【Example】
On a non-alkali glass substrate of 360 × 465 mm and a thickness of 0.7 mm, the pitch is 456 μm in the substrate width direction, the pitch is 152 μm in the longitudinal direction of the substrate, the line width is 30 μm, and the number of RGB pixels is 1920 (substrate longitudinal direction). Creates a black matrix film with a thickness of 1 μm in a lattice shape of × 480 (substrate width direction) and a diagonal length of 14.4 inches (219 mm in the substrate width direction and 292 mm in the substrate longitudinal direction). did. The black matrix film was obtained using titanium oxynitride as a light shielding material and polyamic acid as a binder.
[0069]
Subsequently, after removing particles on the substrate by wet cleaning, polyamic acid as a binder, γ-butyrolactone, a mixture of N-methyl-2-pyrrolidone and 3-methyl-3-methoxybutanol as a solvent, and Pigment Red 177 as a pigment. An R-color coating solution, which was mixed at a solid content concentration of 10% and further adjusted to a viscosity of 50 cps, was uniformly coated with a die coater at a speed of 3 m / min at a thickness of 20 μm. Here, the slit die of the die coater had a slit gap of 100 μm, a slit width of 220 mm, and a gap between the slit die and the substrate of 100 μm. In this die coater, a laser length measuring device (LS-5120, manufactured by Keyence Co., Ltd.) that irradiates and receives a laser beam is sandwiched between a laser irradiation unit and a stage that holds and moves the substrate in the substrate width direction. And the distance between the light receiving portions was set to 500 mm. Also, when the stage is moved when the substrate is not placed and the laser beam of the laser measuring instrument is blocked, the laser measuring instrument displays 50 mm in the vertical direction between the laser measuring instrument and the stage. The relative position was adjusted. As a result, it was possible to detect a foreign matter having a minimum size of 40 μm in the vertical direction and a raised substrate.
[0070]
By detecting this length measuring device, when there was a raised portion or foreign matter raised 80 μm from the substrate, the slit die was retracted, and 30000 substrates were continuously applied. As a result, the foreign matter having a size of 80 μm or more with the slit die retracted and the raised portion of the substrate were found in 2 of 30000 coatings. Any raised part or foreign matter on any substrate was found during application, and since the discharge of the application liquid was stopped halfway and application was only partway through, both substrates were sent to the substrate recycling process to make a glass substrate Reused.
[0071]
After application of the R color coating solution, it is dried at 100 ° C. for 20 minutes with a drying apparatus using a hot plate. After applying 10 μm of a resist solution having a solid content concentration of 10% and a viscosity of 8%, it is performed on a 90 ° C. hot plate for 10 minutes. After drying, exposure / development / peeling was carried out, leaving a color coating film only in the R pixel portion, and curing was performed by heating on a hot plate at 260 degrees for 30 minutes.
[0072]
Formation of the same color coating film For the G and B colors, each color coating film was formed in the same manner as in the R color using a die coater, the above-described application condition determining means, and other similar processes. Here, the G color coating solution is an R color coating solution in which the pigment is Pigment Green 36 and the viscosity is adjusted to 40 cps at a solid content concentration of 10%. The B color coating solution is an R color coating solution. The pigment was changed to Pigment Blue 15 and the viscosity was adjusted to 50 cps at a solid content concentration of 10%.
[0073]
Finally, ITO was deposited by sputtering to create a color filter. The obtained color filter had no foreign matter such as agglomerates of pigment and abrasion powder, and the chromaticity was uniform over the entire surface of the substrate, and was satisfactory in quality.
[0074]
【The invention's effect】
As described above, in the present invention, the protruding portion of the substrate due to foreign matter biting or the like or foreign matter on the surface is detected, and the applicator is retracted without stopping the movement of the substrate or the applicator to avoid contact. Therefore, it becomes possible to protect the applicator without operating time and production loss. Furthermore, since the discharge of the coating liquid from the applicator is stopped when the applicator is retracted, the coating liquid can be saved.
[0075]
Further, the detection of the foreign matter on the raised portion or the surface of the substrate is performed by means that does not contact the substrate or the foreign matter, or the operation of avoiding or mitigating the contact between the detection member and the foreign matter on the raised portion of the substrate or the surface. Therefore, it is possible to prevent damage to the substrate and the detection member, and to prevent the loss of operating time caused by taking out the damaged product, cleaning and replacing the detection member in addition to the damage of the product and the detection member. Can do. Furthermore, secondary defects such as a coating defect due to scattered scattered objects and a new substrate bulge caused by biting damaged scattered objects can be avoided.
[0076]
Furthermore, since the above excellent means are used for the production of the color filter, a large amount of the color filter can be produced stably and with high productivity.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of a die coater according to an embodiment of the present invention.
2 is a schematic configuration diagram showing the die coater of FIG. 1 including a coating solution supply system. FIG.
FIG. 3 is a schematic front view of a detection system in a coating apparatus according to another embodiment of the present invention.
4 is a plan view showing a state of occurrence of a light stripe pattern in the detection system of FIG. 4; FIG.
FIG. 5 is a schematic front view of a detection system in a coating apparatus according to still another embodiment of the present invention.
6 is a side view of the detection system of FIG.
FIG. 7 is a schematic front view of a detection system in a coating apparatus according to still another embodiment of the present invention.
8 is a plan view of the detection system of FIG.
FIG. 9 is a schematic front view of a detection system in a coating apparatus according to still another embodiment of the present invention.
FIG. 10 is a schematic front view of a detection system in a coating apparatus according to still another embodiment of the present invention.
11 is a plan view of the detection system of FIG.
FIG. 12 is a schematic side view showing an embodiment applied when the present invention is applied to a sheet-like material with a slit die.
[Explanation of symbols]
2 base
6 stages
14 Feed screw
18 AC servo motor
22 Thickness sensor
32 Die holder
40 Slit die (applicator)
44 Syringe pump
50 tanks
54 Computer
62 Manifold
64 slits
72 Discharge port surface
100 Detection system A
104 Laser irradiation part
106 Laser receiver
108 Length calculator
200 Detection system B
202 camera
204 Light stripes
210 Slit light source
220 Image processing apparatus
250 Detection system C
254 wire
256 Displacement meter
300 Detection system D
301 Detection surface
302 Detector
304 holder
314 Proximity sensor
316 axis of rotation
318 stopper
320 counterweight
340 Floating detector
342 slit
400 Detection system E
402 slit
404 Floating detector
406 rail
408 Information board
412 Proximity sensor
420 Stopper
422 blocks
426 Bottom
500 Backup roll
502 Slit die
504 sheets
506 pump
510 Lifting mechanism
512 Laser irradiation unit
513 Laser receiver
514 Foreign object
A Glass substrate (Coating member)
C Coating liquid bead

Claims (3)

The discharge port of the applicator is brought close to the member to be coated up to a certain gap, and at least one of the applicator and the member to be coated is relatively moved while discharging the coating liquid from the discharge port of the applicator to the member to be coated. In the coating method of forming a coating film on the member to be coated, the detection of the raised portion on the surface of the member to be coated or the foreign matter on the member to be coated is performed by irradiating a laser beam in the longitudinal direction of the applicator and blocking the laser beam. performed based on the length, before the raised portion or a foreign matter comes into contact with the applicator, it retracts the applicator, to stop the relative movement of the applicator and the coating member, further coating from the applicator An application method characterized by stopping the discharge by stopping the discharge of the liquid . 2. The coating method according to claim 1 , wherein after the coating is interrupted, the coated member is turned to a regeneration process or is returned to a process before coating to resume coating. Method of manufacturing a color filter, which comprises manufacturing a color filter by using the coating method according to claim 1 or 2.

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