JP2009109799A - Coating device and coating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating device by which a color filter or the like satisfying requirement on specifications of chromaticity is formed at a low cost, uniformly and without generating irregularity in a large coating region. <P>SOLUTION: The coating device includes a coating head which has several discharge nozzles for supplying a coating material to an object to be applied, a stage which holds the object to be applied and a control means which instructs to discharge while holding at least one unused discharge nozzle among several discharge nozzles for application onto the object to be applied. The coating material is applied onto the object to be applied while uniformizing discharge amount of the coating material from respective discharge nozzles. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a coating apparatus that supplies a coating material to a coating object held at a predetermined position in the apparatus by a coating head having a plurality of discharge nozzles.

  Recent progress in image display technology of information terminals is remarkable, and display devices (displays) with very high definition are manufactured and put into practical use even for large screens or small screens. Under such circumstances, there is a strong demand for a display that enables high-quality image display at low cost. There is a color filter as a key device of a display that meets such demands, and various devices have been incorporated into the color filter manufacturing method and apparatus.

  One of the development techniques for such a manufacturing method and apparatus is a conventional glass substrate in which a light-shielding portion is formed in a matrix shape by using various materials having a light-shielding function. A coloring material is applied to a glass substrate or the like by using a coating technique in order to color the inside of the grid so as to give a function as a color filter. However, in this construction method, the steps of applying the RGB three color coloring materials are independent, and each step requires a shielding member (mask) that requires very high accuracy for light shielding, etc. However, there is a problem that the manufacturing cost is high in terms of the devices and members to be used. In place of such a method at present, recently, using a coating apparatus equipped with an inkjet head as a coating head, a discharge nozzle in which a coloring material as a coating material is formed on the inkjet head on a glass substrate or the like in which a light-shielding portion is formed in a matrix shape A method of manufacturing a color filter by supplying and applying from an inkjet nozzle is proposed (see Patent Document 1 and Patent Document 2).

JP 2002-273868 Japanese Patent No. 3925525

  When applying coloring materials, etc. using an inkjet head, when applying coloring materials, etc. over a large area such as a display with a large screen, or even if the application area required for each product is small, a large amount on one substrate If it is going to produce through an application process simultaneously in parallel, it will be necessary to supply a large amount of coloring materials etc. in order to apply coloring materials etc. to an effective area with a large area like a large display as a result. In such a case, in order to efficiently complete the coating process, the material is supplied by relative movement between the coating head and the substrate, such as by scanning (moving) the coating head once in a large area (width). It is necessary to apply, and it is necessary to arrange a plurality of inkjet heads for applying the coloring material in parallel. However, when a plurality of ink jet heads are simply arranged in parallel, the width of the entire developed ink jet head portion increases.

  As a method for solving this problem, Patent Document 1 discloses a method in which the inkjet heads are arranged at an inclination in the arrangement and arrangement of the inkjet heads.

  In addition, in order to realize a large coating area as described above with a small number of coating steps, a single coating is performed by mounting a necessary number of inkjet heads having inkjet nozzles of a certain limited width on a moving base. A large-sized coating apparatus is required so that the operation (process) can be completed. In such a case, depending on the arrangement of a plurality of ink jet heads, adverse effects due to the arrangement, for example, variations in the coating amount due to uneven ink discharge amount, and resultant color unevenness may occur.

  Under these circumstances, the present inventors are working on the development of a coating method and apparatus that are applied to the coating by the current inkjet head, and in the case where the inkjet nozzles arranged at a fine pitch are simultaneously ejected from a continuous inkjet nozzle, When paying attention to one inkjet nozzle, it was confirmed that the discharge amount of the coating material increased or decreased by 5 to 10% compared to the case of single ejection due to the influence of the ejection of the adjacent inkjet nozzle.

Accordingly, when the continuous inkjet nozzles are simultaneously driven to discharge, the inkjet nozzles located at both ends of the continuous inkjet nozzles that have been driven to discharge reduce the discharge amount of the coating material by about 10% compared to the intermediate inkjet nozzles.
In other words, the discharge amount of the ink jet nozzles located at both ends of the ink jet head is always smaller than that of the other ink jet nozzles, and when continuous application is performed according to the movement of the ink jet bar that moves linearly, It was confirmed that a portion with a small coating amount appeared in a streak pattern in the coating region through which the nozzle passed.

  Patent Document 2 discloses a proposal for avoiding such adverse effects, and discloses that the occurrence of color unevenness can be suppressed by introducing a coating apparatus and a coating method. However, in the conventional color filter manufacturing apparatus by applying a liquid in which a plurality of inkjet heads are arranged in Patent Document 2, inkjet nozzles having a low discharge amount at both ends of the inkjet head are continuous as they are. Partially ejected / applied sections by inkjet nozzles with low application amount are continuous in the moving direction in the application sections with small amount of coloring material by ejection / application of the same inkjet nozzle, and color transmission by the corresponding coloring material Defects in color can occur linearly. If the inkjet heads are arranged and arranged in a direction perpendicular to the moving direction so as not to use the part with a low discharge amount, a large waste is generated in the arrangement space of the inkjet head, leading to an increase in the size of the apparatus. Also, it is uneconomical not to use the nozzles at both ends of all inkjet heads.

  In the present invention, even if an inkjet nozzle that inevitably appears on the inkjet nozzle at the end of the inkjet head as in Patent Document 2 and uses a small discharge amount of the coloring material, the chromaticity required for the color filter can be obtained. It is an object to realize a coating method and a coating apparatus that realizes within 3% by converting the allowable value of three thousandths to the allowable value of the application amount of the coloring material to each pixel of the color filter substrate. .

For this reason, in the present invention,
A coating apparatus that sprays and coats a coating material as a small amount of droplets on a coating target with a coating head having a plurality of discharge nozzles,
In the step of relatively moving the application head and the application object, supplying an application material to the application object, and applying an effective application area of the application object,
A control unit is provided that performs discharge while sandwiching one or more unused discharge nozzles from among a plurality of discharge nozzles for applying to the application object.
In addition, a control unit that performs discharge by sandwiching one or more unused discharge nozzles from among a plurality of discharge nozzles for applying to the application object can select a pattern that sandwiches unused discharge nozzles at each discharge timing. It was set as the structure which has two or more.
Furthermore, it comprises a discharge nozzle control means capable of changing the amount per discharge discharged from each discharge nozzle in the coating head,
The application material is applied to the application object by controlling the discharge nozzle control means so that the total amount per discharge of each discharge nozzle in the application head can be made to approach uniformly for each unit region to be applied. The configuration.

  According to claim 1 or claim 4 of the present invention, the total amount per coating area of the coating material ejected at a time from each ejection nozzle of the coating head is made uniform, and a plurality of coating heads are mounted vertically and horizontally. By applying the coating material by moving the coating head or the object to be coated, it is possible to apply a large area with little variation in the coating amount, and it occurs in a continuous area due to the linear movement of the coating head. It is possible to wipe out the occurrence of easy stripe-like coating unevenness.

  According to claim 2 or claim 5, even when an application failure occurs in a part of the nozzles of the application head, there is a variation in application in a certain pattern in an area where the nozzle in which the failure has occurred should be applied. It is possible to prevent the occurrence of this phenomenon, or due to the application operation in intermittent application operation, the time interval of the discharge operation by the same nozzle becomes longer, and the occurrence probability is high in the nozzle where the application operation pause of the discharge nozzle is prolonged. Thus, it is possible to realize a stable coating with less occurrence of defective discharge due to, for example, the drying of the coloring material staying in the nozzle and the discharge of droplets from the opening stops.

  And according to Claim 3 or Claim 6, the change of the discharge amount for each discharge nozzle is suppressed by the control means, or the discharge amount is increased or decreased as necessary, and the application region partitioned into the application objects It is possible to control the total coating amount for each unit area, and to apply the coating amount with higher accuracy not only in the narrow area of the partial application area of the object to be applied but also in the entire application area. Can be realized.

  Hereinafter, embodiments of a coating apparatus of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a color filter manufacturing apparatus is described as an example.

  FIG. 1 is a perspective view showing an embodiment of a coating apparatus for producing a color filter. The color filter manufacturing apparatus of this example supports a suction table 3, a coating gantry 4, a camera gantry 6 and the like on a machine base 1. The suction table 3 as a holding stage holds the glass substrate 2 by suction. In order to achieve the positioning of the glass substrate 2, the suction table 3 is rotationally driven by a driving mechanism and a guide mechanism (not shown) and in the Y direction. Driven. The application gantry 4 holds the inkjet head bar 5 and is driven in the X direction by a drive mechanism and a guide mechanism (not shown) in order to apply a coloring material to the glass substrate 2. Moreover, in order to adjust the relative position with respect to the glass substrate 2, it drives to a Z direction and a Y direction by the drive mechanism and guide mechanism which are not shown in figure.

  The camera gantry 6 holds alignment cameras 7 and 8 for alignment of the glass substrate 2 and holds a scan camera 9 that is a measuring means for detecting the coloring material supplied to the glass substrate 2. Is more preferable, and is driven in the X direction by a drive mechanism and a guide mechanism (not shown) to detect alignment and landing colored material. Further, the alignment cameras 7 and 8 and the scan camera 9 are driven in the Y direction by a drive mechanism and a guide mechanism (not shown). The alignment cameras 7 and 8 detect marks (not shown) on the glass substrate 2, rotate the suction table 3 based on the mark detection results by the alignment cameras 7 and 8, and / or move in the Y direction. By doing so, alignment of the glass substrate 2 can be achieved. The alignment error in the X direction can be achieved by adjusting the ejection timing. Here, X and Y represent directions orthogonal to each other set to define a plane parallel to the upper surface of the glass substrate 2 held by suction by the suction table 3, and Z is a plane defined by X and Y. The direction orthogonal to

  In addition, by adopting a two-dimensional CCD camera instead of the scan camera 9, it is possible to measure the height of the landing mark, and depending on the shape of the droplet at the time of landing obtained in advance for the coloring material to be used, The volume of the droplet can be calculated by measuring the height, and the discharge amount of the coloring material from each inkjet nozzle can be known with higher accuracy.

FIG. 2 is a schematic diagram illustrating an example of the configuration of the inkjet head bar 5.
In this example, a total of 30 heads are shown in which one inkjet head 51 is arranged in five rows in a staggered manner in six rows.

FIG. 3 shows an arrangement pitch of the inkjet nozzles 52 provided in the inkjet head 51 in a direction perpendicular to the moving direction of the inkjet bar 5. Ink jet nozzles 52 that discharge coloring materials are shifted by an arrangement pitch P on each of the five stages of heads, and adjacent ink jet heads 51 are arranged so that the density of the application nozzles at every five stages is continuous. The inkjet heads 51 are arranged in accordance with the width to be applied at a time (in the example of FIG. 2, six rows and 30 inkjet heads 51 are mounted).
Next, an example of the coating operation of the present invention based on the arrangement of the ink jet nozzles 52 will be described.
FIG. 4 shows an inkjet nozzle 52 to be driven at the time of application as a basic operation example at the time of ejection with a circle around it. In this figure, every other inkjet nozzle 52 to which a control command for ejection operation is to be transmitted is arranged in an orderly manner in one inkjet head 51.
By doing so, the pressure of the coloring material inside the inkjet head 51 is inevitably generated when the adjacent inkjet nozzles 52 are simultaneously operated, and the pressure rises due to the interference caused by the simultaneous ejection operation of the adjacent inkjet nozzles 52. It has very little effect on changes in the discharge rate.

  Next, a mechanism for uniformly coating the coating area over the entire surface by the coating apparatus of the present invention will be described.

  As an embodiment of the present invention, a description will be given by applying and filling an appropriate amount of a coloring material into a pixel having a width of 180 μm and a length of 530 μm that can be used for a typical high-definition television receiver of 37 inch size.

  In this case, the arrangement density of the inkjet nozzles 52 is 1800 dpi, the displacement of the positions of the ejected droplets is equal to the application interval P (pitch) is 14.11 μm, and 1 of the coloring material from one inkjet nozzle 52 is 1 The discharge amount is 30 pl (picoliter), and a total of 1500 pl is discharged and applied.

  On the other hand, the present inventors now have an allowable value of chromaticity as a color filter of 3/1000 in the entire effective screen area, and an allowable value of variation in the coating amount of the coloring material that realizes the allowable value of chromaticity. The coating apparatus according to the present invention satisfying the specifications will be described with reference to a target specification of the color filter.

  In the measurement of the landing mark in advance of the ink jet nozzle 52, the average diameter of the droplets in flight on the substrate is 40 μm, so that the coloring material overcomes the matrix-shaped light shielding portion formed on the substrate and is adjacent to it. In order to avoid mixing into the pixel, the area outside the position of 20 μm, which is the radius value of the landing mark of the coloring material applied from the inkjet nozzle 52 to the substrate from the edge of both ends of 530 μm in length, is set as the discharge prohibited area. Application is performed by discharging and applying a coloring material to each pixel formed on the substrate by discharging from the inkjet nozzle 52 located between 490 μm. Therefore, from the arrangement and arrangement density of the 1800 dpi inkjet nozzles 52, the number of inkjet nozzles 52 that can discharge and apply a coloring material to one pixel area is 34.

On the other hand, under the control of the control means, for each pixel of the entire substrate including the effective area of the color filter, a discharge command is sent to the inkjet nozzle 52 selected from the corresponding 34 inkjet nozzles 52 to discharge and apply the coloring material. Thus, the discharge control is performed so that the coloring material of 1500 pl per pixel having a size of 530 × 180 μm falls within the allowable amount of the coloring material within 3% in total.
The discharge amount of the coloring material from each ink-jet nozzle 52 is measured by a test shot of each of the equipped ink-jet heads 51 performed in advance or by a test pattern inspection to be described later. Based on the numerical values stored as data such as the diameter and volume of the landing marks in pattern application, or the data obtained by measuring the ejection amount of the ink jet nozzles 52 of the respective ink jet heads 51 in advance, the numerical values and data are stored in the storage element. Selection of the inkjet nozzle 52 and control of the number of ejections are performed using numerical values stored as a table, and the chromaticity specifications in the effective area of the color filter are satisfied.

  FIG. 5 is a graph showing the discharge speed of the coloring material discharged from each inkjet nozzle 52 when the inkjet nozzles 52 adjacent to the inkjet nozzles 52 arranged in the width direction of the inkjet head 51 used in the present invention are simultaneously discharged. The discharge speed of several nozzles at both ends is about 10 to 15% lower (= the speed and the discharge amount are proportional and the discharge amount is small).

  FIG. 6 is a graph showing the discharge speed from the inkjet nozzle 52 when every other adjacent inkjet nozzle 52 arranged in the same inkjet head 51 discharges the coloring material, and can be seen in FIG. In the operating conditions in which the adjacent inkjet nozzles 52 are not operated simultaneously (= discharging across one or more unused inkjet nozzles 52), no decrease in the ejection speed of the inkjet nozzles 52 located at both ends is confirmed. The discharge amount of the coloring material from the ink jet nozzles 52 in the ink jet head 51 is uniform, and the ink jet nozzles 52 in the ink jet head 51 can be operated without distinction by optimizing the control command of such discharge operation.

  The arrangement pitch P of the 1800 dpi inkjet nozzles 52 is 14.11 μm. This number is one inkjet head 51 because of restrictions on the size and mechanism of the members constituting the inkjet nozzles based on the current basic inkjet system. In other words, the configuration is realized by the five-row basic inkjet head 51, and the arrangement interval of the inkjet nozzles 52 formed in one inkjet head 51 is set to 70.56 μm at 360 dpi.

In such a setting of the coating apparatus, 34 inkjet nozzles 52 arranged at an effective coating width of 490 μm and a pitch of 14.11 μm are included, and one inkjet head 51 is equipped with the inkjet nozzles 52 at a pitch of 70.64 μm. Therefore, when it is configured in five rows, six ink jet heads 51 at one end and seven ink jet nozzles 52 in the other ink jet heads 51 are targets for the discharge operation of the coloring material.
In this case, every other inkjet nozzle 52 can be operated in the combination of three inkjet heads 51 in the inkjet head 51 at one end and three and four combinations in the remaining inkjet head 51. With this, the discharge operation can be performed. In order to eject 50 coloring materials from the operable inkjet nozzle 52, the five inkjet heads 51 arranged can be
1) A total of 17 3 + 4 + 3 + 4 + 3 2) A total of 17 inkjet nozzles 52 of 3 + 3 + 4 + 3 + 4 can be operated to discharge, so that 50 discharges of coloring material can be secured by performing 3 discharges each. In this case, the total discharge amount of the ink jet nozzles 52 that can be selected has a margin of 2% for one discharge of the coloring material, and even when the discharge amount of each ink jet nozzle is slightly reduced, the appropriate discharge / A coating amount can be secured.

  Therefore, by increasing the number of the groups of the inkjet heads 51 in the 5-row configuration and continuously arranging them, it is possible to configure the inkjet bar 5 having a required coating width, and in response to a request for coating a large coating area. However, it is possible to design the ink jet head bar to be used in consideration of the necessary process time and the like.

  The ink jet head bar 5 shown in FIG. 2 is for applying any of red (R), green (G), and blue (B) coloring materials. An inkjet head bar for applying the material is also provided.

  FIG. 7 is a schematic block diagram showing a configuration for controlling the inkjet head bar 5 to select the inkjet nozzle 52. In this configuration, the scan camera 9 which is a measuring unit and the image data by the scan camera 9 (for example, image data corresponding to the state in which the coloring material is discharged and applied from all the inkjet nozzles 52 to the test region) are input. Image processing apparatus 11 that calculates the X, Y coordinates of the landing mark of the coloring material discharged from each inkjet nozzle 52 and the diameter, area, or volume of the coloring material, and necessary data such as the calculated diameter, area, or volume Ink jet nozzles to be operated in consideration of the memory 12, which is a holding means for storing / holding the discharge data table, the data such as the diameter, area, or volume held in the memory 12 and the data in the discharge data table In order to select 52, an input / output interface for exchanging data and control signals with an external peripheral device. And a control unit 13 of the inkjet head bar 5 which is a control means for driving and stopping, including peripheral circuits and arithmetic circuits responsible for such face.

  Therefore, by providing this measuring means and holding means, it is possible to update the area, diameter, or volume held in the memory 12 each time the application operation by the ink jet head bar 5 is performed. In performing the next coating operation according to, the inkjet head bar 5 is controlled by selecting the inkjet nozzle 52 to be operated in consideration of the latest area, diameter, or volume and issuing a control command for the ejection operation. Can do.

  Note that the control device 13 receives data from the respective ink-jet nozzles 52 held in the memory 12 such as data such as the volume of the landing marks measured by discharging the coloring material from the respective ink-jet nozzles 52 and data in the discharge data table. According to the discharge amount data, the supply amount of the coloring material is determined by selecting the inkjet nozzle 52 to be discharged and the number of discharges of the droplets of the coloring material so that the supply amount of the coloring material to be landed on each pixel region 23 is constant. It is preferable to control the corresponding inkjet head 51 and inkjet head bar 5 in order to average over the entire coating region, and as a result, the chromaticity requirement as a color filter is satisfied.

  Alternatively, the discharge amount from each inkjet nozzle 52 held in the memory 12 such as data such as the volume obtained by measuring the landing mark from which the coloring material was discharged from each inkjet nozzle 52 or the data in the discharge data table. In order to optimize the supply amount of the coloring material to be landed on each pixel area 23, the selection of the corresponding inkjet nozzle 52 to be ejected and the ejection command of the number of droplets from the inkjet nozzle 52, etc. In order to keep the supply amount of the coloring material within the allowable error range, it is preferable to control the corresponding inkjet head 51 and inkjet head bar 5 so that the coating amount of the entire coating region is within the allowable range of chromaticity. As a result, the color filter It satisfies the chromaticity requirement.

  In the former case, the coating quality of the coloring material for the pixel region 23 can be remarkably improved. In the latter case, even the ink jet nozzles 52 in which the discharge amount per time for the pixel region 23 is increased or decreased can be used for the coating operation, and the number of usable ink jet nozzles 52 can be maintained while maintaining the coating quality of the coloring material. It is possible to achieve an increase in both.

  Next, the operation of the color filter manufacturing apparatus having the above configuration will be described.

  FIG. 8 is a timing chart for explaining the processing of the coloring material application and the test pattern inspection.

  FIG. 9 shows a state in which six color filters CF are formed on the glass substrate 2, and a test pattern TP for each coloring material is formed in a surplus area outside the color filter CF. .

  FIG. 10 is an enlarged view of the test pattern TP forming portion, and shows the test pattern TP formed by the ink jet nozzles 52 for three colors as being inspected by the camera gantry 6. This test pattern TP is the shape of the landing mark of the coloring material discharged from each inkjet nozzle 52 on the glass substrate.

  The coloring materials are separated from each other and land in a zigzag pattern. By doing so, the interval between the coloring materials is large, the image processing at the time of measurement is widened, the inspection accuracy can be improved, and the test pattern TP can be inspected by the scan camera 9 of the camera gantry 6, and the ink landing trace In addition to the X and Y coordinates, the diameter, area or volume of the ink landing mark is also measured as necessary. Then, when an improper ink landing mark shape or ejection failure such as non-landing is detected, necessary countermeasures (color filter production interruption, ink jet head 51 replacement, etc.) are immediately taken as described later. It is possible to minimize the production of defective products.

  FIG. 11 is a flowchart for explaining an example of the test pattern inspection process. Note that the timing chart of FIG. 8 does not show processing based on the flowchart of FIG.

  The test pattern inspection process will be described with reference to FIG.

  In step SP1, after the test glass substrate is carried into the suction table 3 by a carry-in robot (not shown) or the like, in step SP2, rough positioning of the test glass substrate is achieved by external shape regulating means (not shown). In step SP3, the test glass substrate is sucked by the suction table 3. Thereafter, in step SP4, the camera gantry 6 is moved forward. In step SP5, the alignment mark of the test glass substrate is detected, and the Y direction is detected. Positioning and alignment in the direction of θ (rotation around the Z axis) are achieved, and in step SP6, the camera gantry 6 is moved backward.

  Next, in step SP7, the coating gantry 4 is moved forward / backward, and the X coordinate value of the coating gantry 4 is output. In step SP8, the coating gantry 4 reaches the test pattern coating position based on the X coordinate value. If the test pattern application position has not been reached, the process of step SP7 is performed again.

  If it is determined in step SP8 that the application gantry 4 has reached the test pattern application position, the movement of the application gantry 4 is stopped in step SP9, and the liquid of the coloring material is discharged from all the inkjet nozzles 52 of the inkjet head bar 5. In step SP10, the application gantry 4 is moved back and stopped at the standby position.

Next, a flow for imaging and inspecting the test pattern (TP) is entered. Here, in step SP11, the camera gantry 6 is moved forward, and in step SP12, it is determined whether or not the camera gantry 6 has reached the test pattern inspection position. judge.
If the test pattern inspection position has not been reached, step SP11 is performed again.

  If it is determined in step SP12 that the camera gantry 6 has reached the test pattern inspection position, the camera gantry 6 is stopped in step SP13, and the scan camera 9 is moved in the Y direction in step SP14 to perform the test. The test pattern is imaged to the end while detecting the pattern, and then the scan camera 9 is returned to the Y direction.

  After the processing of step SP14, in step SP15, the camera gantry 6 is moved back and stopped at the standby position to finish the “test pattern (TP) imaging flow”, and in step SP16, the suction of the test glass substrate is released. , Discharge and finish the series of processing.

  In parallel with the processing in step SP15 and step SP16, in step SP17, the detection signal from the scan camera 9 is image-processed, and the X, Y coordinates and the diameter, area and / or volume of the landing mark of the coloring material are measured. In step SP18, the coordinate position information detected from the colored material landing mark of the test pattern is input, and in step SP19, the position information (coordinate values) of all the pixels on the test glass substrate is input. In SP20, other parameters are input. In step SP21, the data table is calculated / created. In step SP22, the calculation result is stored in the ejection data table, and a series of processing such as image processing and measurement / calculation is completed. .

  Next, an example of the color filter manufacturing process will be described with reference to the color filter manufacturing flowchart shown in FIG.

  In order to realize efficient operation of the apparatus, the application gantry 4 needs only one reciprocating operation with respect to the required application region so that the application operation is completed by “one stroke writing” from a predetermined start position of the application gantry 4. Thus, it is desirable to set the width of the effective inkjet head nozzle.

  In step SP1, after the glass substrate 2 is carried into the suction table 3 by a carrying robot (not shown) or the like, in step SP2, the rough positioning of the glass substrate 2 is achieved by outer shape regulating means (not shown). In step SP3, the glass substrate 2 is sucked by the suction table 3, and then in step SP4, the camera gantry 6 is moved forward. In step SP5, the alignment mark of the glass substrate 2 is detected, and the Y direction, θ ( The alignment of the glass substrate 2 is achieved by positioning in the theta direction, and the camera gantry 6 is moved back in step SP6.

  In step SP7, it is determined whether the application is the forward pass application or the return pass application.

  If it is determined in step SP7 that the forward application is performed, in step SP8, the application gantry 4 is moved forward, and the X coordinate value of the application gantry 4 is output. If it is determined, the coating gantry 4 is moved back in step SP9.

  When the process at step SP8 or the process at step SP9 is performed, it is determined at step SP10 whether or not the application has been performed up to the end of the application region.

  If it is determined in step SP10 that the application has not been performed until the end of the application region, in step SP11, the X coordinate output signal of the application gantry 4 and the discharge data table are compared, and in step SP12, the X coordinate is It is determined whether or not the discharge data matches. If the X coordinate and the discharge data match, in step SP13, a droplet of the coloring material is discharged by the inkjet nozzle 52. The process returns to step SP7.

The color material droplet discharge operation in step SP13 will be described.
As described above, the number of inkjet nozzles 52 to be ejected based on the control command based on the size of the pixel to be coated is an inkjet positioned within the limited width 490 μm of the pixels to be coated of the corresponding five rows of inkjet heads 51. It is an effective inkjet nozzle except that one of the nozzles at both ends located at the outermost side is out of the restricted width area, and 3 to 4 nozzles are adjacent to each other from the 7 inkjet nozzles 52. When the inkjet nozzles 52 to be driven are driven with the restriction that they are not operated simultaneously, a total of 17 inkjet nozzles of 1) 3 + 4 + 3 + 4 + 3 or 2) a total of 17 inkjet nozzles of 3 + 3 + 4 + 3 + 4 can be ejected.
By executing control commands for three ejection operations for these inkjet nozzles 52, it is possible to fill 1500 pl of a coloring material necessary for one pixel.

For slight variations in the discharge amount of the individual coloring materials from these inkjet nozzles 52,
The amount of ejection from each inkjet nozzle 52 held in the memory 12 such as the volume measured by the control device 13 from the respective inkjet nozzles 52 and the data of the ejection data table, etc. In order to average the supply amount of the coloring material over the entire application region by selecting the combination of the ink jet nozzles 52 to be ejected so that the supply amount of the coloring material to be landed on each pixel region 23 is constant. The inkjet head 51 and the inkjet head bar 5 are controlled, and as a result, the ejection operation is controlled so as to satisfy the chromaticity requirement as a color filter.

Alternatively, each inkjet nozzle held in the memory 12 such as data such as a volume obtained by measuring the landing mark from which the coloring material is ejected from each inkjet nozzle 52 by the control device 13 or data in the ejection data table. In order to optimize the supply amount of the coloring material to be landed on each pixel area 23 based on the discharge amount data from 52, the combination of the corresponding inkjet nozzles 52 to be discharged and the coloring material from the inkjet nozzles 52 are selected. In order to keep the supply amount of the coloring material within the allowable error range by adjusting the increase / decrease of the discharge amount of the ink and the discharge command of the number of droplets, the corresponding inkjet head 51 and inkjet head bar 5 are controlled to It is preferable to make the coating amount within the allowable range of chromaticity, and as a result, color filter It controls the ejection operation of the droplets of the coloring material to meet the requirements of chromaticity as.

  Subsequently, in step SP10, it is determined whether application has been performed to the end based on the X coordinate value.

  If it is determined in step SP12 that the X coordinate does not match the ejection data, or if the process in step SP13 is performed, the process returns to step SP7 to determine the return path.

  If it is determined in step SP10 that the application has been performed up to the end, it is determined in step SP14 whether or not the application is the first time in the forward path. If the application is the first time in the forward path, the application is performed in step SP15. The gantry 4 is moved to the test pattern application position, and a test pattern is formed by the inkjet head bar 5 in step SP16. Specifically, the ink jet head bar 5 is moved in the X direction, the ink jet nozzles 52 that perform the ejection operation are selected from the ink jet nozzles 52 of all the ink jet heads 51, and the coloring material is ejected and applied, thereby staggering. A test pattern is formed.

  If it is determined in step SP14 that it is not the first application of the outward path, or if the process of step SP16 is performed, whether or not a predetermined number of times of application for applying the entire application region has been performed in step SP17. Determine.

If it is determined in step SP17 that the number of times of application has not reached the predetermined number, in step SP18, the application gantry 4 is stopped, the inkjet head bar 5 is moved in the Y direction, and the determination in step SP7 is performed again.
The moving distance in the Y direction is determined by the effective application width of the ink jet head 51 according to the specifications of the ink jet head bar 5, and the entire application area width is completed evenly by scanning evenly.

  If it is determined in step SP17 that the predetermined number of times of application has been performed, the application process is terminated in step SP19, and in step SP20, all obtained in the “TP imaging flow” described in FIG. From the image of the landing mark of the coloring material discharged from the inkjet nozzle 52, it is determined whether or not the ejection failure of each inkjet nozzle 52 exceeds the number allowed in the range of the target pixel unit in the application region.

  As a result of the determination, if the occurrence of ejection failure of the inkjet head 51 exceeding the allowable range is confirmed, the process proceeds to the cleaning flow. If within the allowable range, the suction of the glass substrate 2 by the suction table 3 is performed in step SP21. The glass substrate 2 is unloaded by an unillustrated unloading robot or the like, and the series of processes is terminated as it is.

  On the other hand, if it is determined that the return path is determined in step 7, the application end processing in step SP 19 is performed through the “TP imaging flow” described in FIG. 11 in parallel with the return path movement of the application gantry 4 in step SP 9. Move on.

  In the above-described example, the embodiment in which the application gantry 4 is moved in the X direction with respect to the suction table 3 has been described. However, the application gantry 4 may be fixed and the suction table 3 may be moved. It is.

In the above embodiment, the ink jet nozzle 52 is selected so that the total application amount for the pixels on the color filter is made closer to the required application amount, and per discharge discharged from the ink jet nozzle 52. There is no change in the amount of.
However, nozzle control means (not shown) for providing an inkjet head bar 5 having a plurality of inkjet heads 51 in the coating gantry 4 and changing the amount per ejection discharged from the inkjet nozzles 52 in the inkjet head 51; The upper control means (not shown) controls the control means of the ink jet nozzle 52 so that the total amount per discharge discharged from each ink jet nozzle 52 in the ink jet head 51 approaches a predetermined amount for each ink jet head 51. It is preferable to further include

  For example, the nozzle control means changes the discharge amount per discharge by changing the drive voltage applied to the inkjet nozzle 52.

  The upper control means inputs, for example, the discharge amount non-uniformity data obtained by the scan camera 9 and the like, and the total discharge amount per discharge of each ink jet nozzle 52 in the ink jet head 51 (of the ink jet head 51). The operation command to the control means of each inkjet nozzle 52 is performed so that the discharge amount per discharge) approaches the target discharge amount.

  In this case, the coating amount can be adjusted for each inkjet head 51. More specifically, even when a specific inkjet head 51 is affected by the viscosity of the ink and the discharge amount becomes low, an operation command for each nozzle control unit is set by the host control unit, and the nozzle control unit sets the inkjet nozzle. By changing the drive voltage applied to the nozzle 52, it is possible to suppress variations in the discharge amount with the other inkjet heads 51.

As described above, an application example for manufacturing a color filter used in a liquid crystal display device or the like has been described as a typical application example of a coating apparatus. Of course, it can be applied without any trouble.

Perspective perspective view of an embodiment of a coating apparatus An example of the arrangement of the inkjet head of the inkjet head bar An example showing the nozzle arrangement of an inkjet head bar An example of selection when driving an inkjet nozzle Graph showing the ejection speed during simultaneous ejection in the same row for each inkjet nozzle Graph showing discharge speed when discharging every other nozzle in the same row for each inkjet nozzle Block diagram of the controller that selects and discharges inkjet nozzles Timing chart of coating operation and coating pattern inspection process The figure of the state which applied six color filters and a test pattern on the substrate Partial enlarged view of the test pattern formation section Sample flow chart of test pattern inspection process Example of color filter manufacturing process flowchart

Explanation of symbols

2 Glass substrate 3 Suction table 5 Inkjet head bar 9 Scan camera 11 Image processing device 12 Memory 13 Control device 51 Inkjet head 52 Inkjet nozzle

Claims (6)

A coating apparatus that sprays and coats a coating material as a small amount of droplets on a coating target with a coating head having a plurality of discharge nozzles,
In the step of relatively moving the application head and the application object, supplying an application material to the application object, and applying an effective application area of the application object,
A coating apparatus comprising a control unit that performs ejection by sandwiching one or more unused ejection nozzles from among a plurality of ejection nozzles for applying to the application object. In the control means for performing ejection while sandwiching one or more unused ejection nozzles from among the plurality of ejection nozzles for applying to the application object, a plurality of patterns that sandwich unused ejection nozzles can be selected at each ejection timing. The coating apparatus according to claim 1, wherein the coating apparatus is provided. In the coating device according to claim 1 or 2,
Furthermore, it comprises a discharge nozzle control means capable of changing the amount per discharge discharged from each discharge nozzle in the coating head,
The application material is applied to the application object by controlling the discharge nozzle control means so that the total amount per discharge of each discharge nozzle in the application head can be made to approach uniformly for each unit region to be applied. An applicator characterized by that. A coating method in which a coating material is sprayed and applied to a coating target as a small amount of droplets with a coating head having a plurality of discharge nozzles,
In the process of relatively moving the application head and the application object, supplying an application material to the application object, and applying the effective application area of the application,
An application method for applying an application material to the application object, comprising: a control unit that performs discharge with one or more unused discharge nozzles sandwiched among a plurality of discharge nozzles for applying to the application object. In the control means for performing ejection while sandwiching one or more unused ejection nozzles from among the plurality of ejection nozzles for applying to the application object, a plurality of patterns that sandwich unused ejection nozzles can be selected at each ejection timing. The coating method according to claim 4, wherein a coating material is applied to the object to be coated. In the coating method according to claim 4 or claim 5,
Furthermore, it comprises a discharge nozzle control means capable of changing the amount per discharge discharged from each discharge nozzle in the coating head,
The application material is applied to the application object by controlling the discharge nozzle control means so that the total amount per discharge of each discharge nozzle in the application head can be made to approach uniformly for each unit region to be applied. Application method.

Images