JP2008209704A - Alignment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alignment apparatus which can automatically perform alignment of ink jet heads with high accuracy by a mechanism independent from a coating apparatus. <P>SOLUTION: The alignment apparatus has a laser irradiation machine which marks an ink jet head provided at an ink jet head unit with an head alignment mark to be a positioning standard, a camera which measures a position of the head alignment mark marked by the laser irradiator and a position of a nozzle hole of the ink jet head, a relative position measuring mark part for measuring relative positional relation between the laser irradiator and the camera, a control means which acquires a head alignment mark position data based on a measuring state of the camera, a positioning mechanism for positioning the ink jet head based on the head alignment mark position data and a holding means for adjusting height and a position of the ink jet head unit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an alignment apparatus that performs an inkjet head positioning operation in an ink discharge apparatus used for manufacturing a color filter for a liquid crystal display or an electrode for an organic EL display, for example.

  In recent years, with the development of personal computers, the increase in size of liquid crystal televisions and the spread of mobile phones, demand for color liquid crystal displays tends to increase. However, cost reduction is indispensable for further spread, and there is an increasing demand for cost reduction of a color filter having a large cost ratio.

  Currently, (1) a dyeing method, (2) a pigment dispersion method, (3) a printing method, (4) an electrodeposition method, and (5) an ink jet method are known as methods for producing a color filter.

  (1) A dyeing method is a pattern in which a water-soluble polymer for dyeing is formed on a glass substrate, patterned into a desired shape through a photolithography process, and then immersed in a dyeing solution. This is repeated three times to obtain R, G, B color filter layers. The filter obtained by this method has a high transmittance and abundant hue, and since the technology is highly complete, it has been widely used in color solid-state image sensors (CCDs) at present, but it is inferior in light resistance due to the use of dyes. Due to the large number of manufacturing processes, the pigment dispersion method has recently been replaced for liquid crystal display elements (LCD).

  (2) The pigment dispersion method is the most mainstream color filter manufacturing method in recent years. First, a resin layer in which a pigment is dispersed is formed on a glass substrate and patterned through a photolithography process. This is repeated three times to obtain R, G, and B color filter layers. This manufacturing method has a high degree of completeness of the technology, but has a drawback that the number of steps is large and the cost is high.

  (3) The printing method is a color filter layer in which a pigment is dispersed in a thermosetting resin and printing is repeated three times to separate R, G, and B, and then heat is applied to cure the resin. Get. This method does not require photolithography in forming the R, G, and B layers, but has a problem in terms of resolution and film thickness uniformity.

  (4) The electrodeposition method involves electrodeposition coating by applying a high voltage of about 70 V on a previously patterned transparent electrode in an electrolytic solution in which a pigment is dispersed in a water-soluble polymer to form an electrodeposition film. This is repeated three times to obtain R, G, and B color filter layers. This method has the disadvantage that it is necessary to pattern a transparent electrode in advance by photolithography and use it as an electrode for electrodeposition, and the pattern shape is limited, so that it cannot be used for TFT liquid crystal.

  In order to compensate for the above drawbacks, methods for manufacturing color filters using an ink jet method have been actively developed and studied (for example, see Patent Documents 1 to 3). The method using the ink jet method has an advantage that the manufacturing process is simple and the cost is low.

The color filter manufacturing apparatus according to the color filter manufacturing method using the ink jet method is relatively composed of a recording medium and an inkjet head in which a plurality of nozzles are linearly arranged in each color of R, G, B or Y, M, and C. A recording medium feeding means that reciprocates in the main scanning direction and intermittently feeds a set amount in the sub-scanning direction, and moves the ink-jet head in the main scanning direction while transferring ink from the head to the recording medium with a pressure generator. Is pressed at a predetermined pressure, and based on the pressure, ink is ejected from the nozzles on the nozzle forming surface as ink droplets of a controlled size toward the recording medium, and a plurality of colored portions are colored simultaneously for each color.

The ink ejection characteristics from the nozzles of the ink jet head need to be maintained constant. Therefore, in such a manufacturing apparatus, it is important to adjust the nozzle position of each inkjet head with high accuracy and to maintain the nozzle position of each inkjet head in the ejection process.
Japanese Patent Laid-Open No. 9-277571 JP-A-10-332924 JP 2001-343513 A

  However, it takes a very long time to adjust the nozzle position of the inkjet head with high accuracy. In particular, when discharging onto a large recording medium, since the ink jet head is reciprocated many times when the discharge width of the ink jet head is narrow, it is necessary to arrange a number of ink jet heads in order to shorten the tact time. All ink jet heads such as B and B must be adjusted with high accuracy.

  And if it tries to adjust with high precision on a coating device, it will lead to the fall of an operation rate, since it takes time for it, so that there are many inkjet heads.

  Also, if the head nozzle surface is in use for a long period of time or if the maintenance of the nozzle surface is not good, it is easy for ink denatured material to adhere to it, and if it is on the edge of the nozzle, it will interfere with nozzle hole position measurement and alignment This leads to a decrease in accuracy and an obstacle to alignment automation.

  Furthermore, the use of many inkjet heads increases the number of nozzles used, and as an inkjet head unit, the establishment of ejection failure (non-ejection) due to nozzle clogging increases. Conventionally, in such a case, it is necessary to replace the inkjet head and perform position adjustment after the head replacement, which also leads to a reduction in operating rate and an increase in cost.

  Therefore, the present invention can automatically align the inkjet head with a high accuracy by a mechanism independent from the coating apparatus, greatly reduce the setup time during coating, and repair the non-ejection nozzle. It is an object of the present invention to provide an alignment apparatus that shortens the head replacement time and eliminates the position adjustment time after replacement.

In order to achieve the above object in the present invention, first, in the invention of claim 1, a laser irradiator that marks a head alignment mark serving as a position adjustment reference on an ink jet head provided in the ink jet head unit;
A camera for measuring the position of the head alignment mark marked by the laser irradiator and the nozzle hole position of the inkjet head;
A relative position measurement mark unit for measuring the relative positional relationship between the laser irradiator and the camera;
Control means for acquiring head alignment mark position data based on the measurement state of the camera;
A position adjustment mechanism for adjusting the position of the inkjet head based on the head alignment mark position data;
Holding means for adjusting the height and position of the inkjet head unit;
The alignment apparatus is characterized by having:

  According to a second aspect of the present invention, the laser irradiator has an output adjustment function, and removes deposits of defective ejection nozzles by laser light irradiation, and has a function of repairing an inkjet head. The alignment apparatus is described.

  According to a third aspect of the present invention, the alignment apparatus according to the first aspect is provided with a plurality of the cameras.

  According to a fourth aspect of the present invention, in the alignment apparatus according to the first aspect, the position adjusting mechanism adjusts the position of the inkjet head in the nozzle row direction, the height direction, and the horizontal rotation direction. .

  According to a fifth aspect of the present invention, in the alignment apparatus according to the first aspect, the position adjusting mechanism adjusts a position of the ink jet head with reference to an alignment mark provided in the ink jet head unit. .

  According to a sixth aspect of the invention, there is provided the alignment apparatus according to the first aspect, wherein the nozzle position data is sent to the coating apparatus to be utilized in the coating process.

  According to a seventh aspect of the present invention, in the alignment apparatus according to the first aspect, the holding means is compatible with a holding means of a coating apparatus on which an inkjet head unit is mounted.

  According to the alignment apparatus of the present invention, the alignment operation of the inkjet head that has been conventionally performed on the coating apparatus can be automatically performed with high accuracy by a dedicated alignment apparatus different from the coating apparatus. It is possible to perform efficient work, significantly reduce the setup time during coating, and repair and reuse the head that was replaced when non-ejection occurred, reducing the replacement time, There is also an effect that the position adjustment time after replacement is eliminated and the head cost is further suppressed.

  In the embodiment of the present invention, in the color filter manufacturing process by the ink jet method, the fine adjustment mechanism is used to adjust the position of each ink jet head in the nozzle row direction, the rotation direction, the horizontal direction, and the height direction. Alignment device that makes it possible to eliminate non-ejecting head replacement work by making a simple inkjet head arrangement and preventing the operating rate of the coating apparatus from being lowered and repairing the non-ejecting head Is to provide.

  This alignment apparatus is provided independently of the coating apparatus shown in FIG. 2, and has a configuration in which an inkjet head unit adjusted in advance by this alignment apparatus is installed in the coating apparatus to perform a coating operation. However, the data obtained by this alignment apparatus can be transferred to the coating apparatus and used for alignment or the like.

  Specifically, a unit alignment mark is attached to the ink jet head unit, and this alignment mark is detected, and the coordinates (head position data) of the head alignment mark of each head are detected, and a fine adjustment mechanism is used. The heads are aligned and the posture of each inkjet head is maintained. Then, position information (nozzle position data) from the head alignment mark can be sent to the coating apparatus so that it can be utilized, and the coating setup time can be greatly reduced.

  The fine adjustment mechanism also arranges the nozzle rows in parallel in the direction perpendicular to the scanning direction, aligns the head ends so that they move straight in the scanning direction, makes the height horizontal, and places all the heads on the coating stage. Make a certain amount the same height. This can be adjusted not only on the alignment apparatus but also on the coating apparatus by communication from the controller. For such a fine adjustment mechanism, various conventionally known structures can be employed.

  In addition, the manufacturing method of the color filter by the inkjet method basically applies ink onto a transparent substrate such as a glass substrate to form a colored portion. The method includes a method of curing and coloring the ink itself, a method of forming a receiving layer made of a resin having ink absorptivity on a transparent substrate, and applying the ink to the receiving layer for coloring, or on a transparent substrate. The method is broadly classified into a method of applying ink to a bank having a black matrix habitability and coloring, and the present invention is preferably applied to any method.

  First, prior to the description of the alignment apparatus of the present embodiment, a coating apparatus (color filter manufacturing apparatus using an ink jet method) that can be used in combination with the alignment apparatus will be described.

  FIG. 2 is an external view showing an example of a coating apparatus.

  In the figure, an ink jet head unit 1 has a plurality of ink jet heads arranged in parallel, and applies ink to a transparent substrate 2 arranged to face each ink jet head. The maintenance device 3 is for maintaining the ejection stability of the inkjet head.

  The main scanning direction moving device 4 and the sub-scanning direction moving device 5 constitute an XY stage drive system. The main scanning direction moving device 4 moves a Y-direction movable portion (substrate stage) that reciprocates during ink application. On the other hand, the sub-scanning direction moving device 5 moves the X-direction movable portion that is intermittently sent to apply the necessary width to the transparent substrate 2 during ink application.

  In such a color filter manufacturing apparatus, the ink jet head unit 1 is moved in advance relative to the transparent substrate 2 in the main scanning direction, and the ink liquid is ejected from the head onto the transparent substrate 2 to be applied, and ejected a predetermined number of times. After being performed, the discharge characteristics are stabilized using the maintenance device 3.

  Then, after the ejection stability of the inkjet head is improved by the maintenance device 3, the process proceeds to the color filter drawing process.

  First, the inkjet unit 1 is moved to the end of the transparent substrate 2 by the sub-scanning direction moving device 5. The main scanning direction moving device 4 performs main scanning a predetermined number of times n (n is a natural number) to apply ink onto the transparent substrate 2.

  The relationship between the stage and the ink ejection timing during the drawing operation is that the substrate stage moves in the main scanning direction, and ink is ejected from the nozzles of the inkjet head in synchronization with the position in the main scanning direction. Then, after scanning a predetermined number of times, the sub-scanning moving device 5 moves to the end of the uncoated portion of the transparent substrate 2 and moves in the main scanning direction to apply again a predetermined number of times.

  Next, the color filter obtained by the above process will be described.

  As described above, the color filter manufacturing method includes a method of curing and coloring the ink itself, a receiving layer made of a resin having ink absorptivity and the like formed on a transparent substrate, and the ink is applied to the receiving layer. There are a method of applying and coloring, a method of applying ink to a bank having a black matrix habit ink property on a transparent substrate, and a method of coloring.

  FIG. 3 is a schematic view showing an example during coating of a color filter.

  The black matrix 6 includes a soot ink formed on the transparent substrate 2 and serves as a barrier for curing the ink. Further, 7 indicates a Red ink droplet, 8 indicates a Green ink droplet, and 9 indicates a Blue ink droplet. In this example, in order to form colored portions of three colors R, G, and B, three ink jet heads must be used, and ink droplets must be applied to the respective openings of the black matrix. Even when ink is applied to a receiving layer made of an ink-absorbing resin or the like, it must be ejected to a predetermined location in order to prevent color mixing and misdirection of the ejection position.

  If the allowable value of the misregistration error in the main scanning direction is calculated from the pixel size of the color filter as an example, the opening of the black matrix 6 is about 120 μm and the ink droplet diameter is about 110 μm. In consideration of the output variation and the like, the tolerance of the inkjet head position adjustment is about ± 2 μm. Therefore, very high accuracy is required for alignment of the inkjet head and the transparent substrate in the apparatus.

  Next, the inkjet head alignment apparatus according to the present embodiment will be described.

  FIG. 1 is an external view showing the configuration of the inkjet head alignment apparatus according to the present embodiment.

  In the inkjet head unit 1, a plurality of inkjet heads 10 to be aligned are arranged in parallel and supported by an XY stage 11 of an alignment apparatus. On the nozzle formation surface of the inkjet head 10, a nozzle row formed by a plurality of nozzles is provided.

  The ink-jet head unit 1 includes a holder and a plurality of ink-jet heads 10 provided on the holder, and each ink-jet head 10 has two directions perpendicular to the holder on the horizontal plane and a vertical direction via a support mechanism. It is supported finely adjustable and finely adjustable around a vertical axis. In addition, conventionally well-known various structures are employable for such a support mechanism.

  On the XY stage 11 of this alignment apparatus, a laser irradiator capable of marking the alignment mark and repairing the non-ejection nozzle on the inkjet head head 10 is installed.

Until now, the nozzle position was measured and the head position was adjusted, but the head nozzle surface in use may have a denatured ink adhering to it, and if this is at the edge of the nozzle hole, It was an obstacle to the nozzle hole position measurement, and it was a failure of alignment accuracy and alignment automation. For this reason, as shown in FIG. 4, the head alignment mark is marked with two laser non-adhered areas 33 at both ends of the nozzle hole where the ink denatured material does not adhere, and the position thereof is measured. Automatic alignment is now possible.

  Here, since the head alignment is performed by substituting the position of the head alignment mark for the position of the nozzle hole 32, the relative positional relationship between them must be accurate. For this reason, the mark base material 22 installed in the relative position measurement marking unit 21 shown in FIG. 5 is marked with a laser irradiator, and the relative position relationship is determined from the position coordinates of the slider and the observation camera 12 when measured. Can be grasped accurately. Thus, if the head alignment mark position can be recognized, the nozzle hole position can be grasped.

  In addition, since the relative positional relationship between the laser irradiator and the observation camera 12 can be accurately grasped as described above, the ink denatured material and foreign matters adhering to the nozzle holes can be removed by laser light irradiation.

  Furthermore, since there are two head alignment marks on the XY stage 11 and two observation cameras 12, two alignment marks on the inkjet head can be observed simultaneously. That is, it is very advantageous to adjust the X direction and the Y direction of the inkjet head by observing the two alignment marks.

  The X-direction slider 13 and the Y-direction slider 14 move the observation camera 12 when observing the head nozzle surface 31 of the inkjet head 10. The anti-seismic table 15 is provided in order to remove the vibration because the precision alignment is affected if the vibration is received during the precision alignment.

  The head unit holder 16 receives the inkjet head unit 1 and is a mechanism that rotates in the horizontal direction so that the moving directions of the Y-direction slider 14 and the X-direction slider 13 are aligned with the main scanning direction and the sub-scanning direction of the coating apparatus, respectively. ing.

  Then, the alignment mark attached to the inkjet head unit 1 is read and adjusted so that the main scanning direction of the coating apparatus and the Y-direction slider 14 are parallel, and the nozzle row of the inkjet head is parallel to the X-direction slider 13. Align the inkjet heads. The observation display 17 displays images from the two observation cameras 12, and is used to display a reticle or the like on the screen and align the head alignment marks.

  The alignment control panel 18 is used for switching and adjusting the rotation signal of the fine adjustment mechanism motor. The controller 19 rotates the motor of the fine adjustment mechanism and is used for adjusting the position of the inkjet head. The ink-jet heads to be adjusted in order on the alignment control panel 18 are switched, and the position accuracy is adjusted using the controller 19 each time. The motor switching BOX 20 switches the drive motor and is controlled by the alignment control panel 18.

  The holding means of the inkjet head unit 1 supports, for example, an inkjet head unit frame like the coating apparatus, and even if the head unit undergoes elastic deformation due to its own weight, in order to make the same deformation on the alignment apparatus. The alignment is not affected.

That is, the holding means of the alignment apparatus includes the head unit holder 16 and adjusts the height and position of the inkjet head unit 1 and is compatible with the holding means on which the inkjet head unit 1 is mounted in the coating apparatus. Is.

  If a deviation in ejection is found during coating and it is desired to adjust the position of the ink jet head, the controller 19 can be connected to the motor switching BOX 20 to adjust the predetermined ink jet head. Therefore, when adjusting a small number of inkjet heads, it is not necessary to carry the inkjet head unit to the alignment device.

  Moreover, it is possible to shorten the setup time at the time of coating by sending the nozzle hole position data of the inkjet head arranged at a predetermined position to the coating apparatus after alignment.

It is an external view which shows the structure of the alignment apparatus of the inkjet head by this embodiment. It is an external view which shows an example of a coating device. It is a schematic diagram which shows the example during application of a color filter. It is explanatory drawing which shows a head alignment mark position. It is explanatory drawing which shows a relative position measurement marking part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Inkjet head unit 2 ... Transparent substrate 3 ... Maintenance apparatus 4 ... Main scanning direction moving apparatus 5 ... Sub-scanning direction moving apparatus 6 ... Black matrix 7 ... Red ink droplet 8 ... Green ink droplet 9 ... Blue ink droplet 10 ... Inkjet head DESCRIPTION OF SYMBOLS 11 ... XY stage 12 ... Observation camera 13 ... X direction slider 14 ... Y direction slider 15 ... Isolation table 16 ... Head unit holder 17 ... Observation display 18 ... Alignment control panel 19 ... Controller 20 ... Motor switching BOX
21 ... Relative position measurement marking part 22 ... Mark substrate 31 ... Head nozzle surface 32 ... Nozzle hole 33 ... Ink non-adhesion area

Claims (7)

A laser irradiator for marking a head alignment mark serving as a position adjustment reference on an inkjet head provided in the inkjet head unit;
A camera for measuring the position of the head alignment mark marked by the laser irradiator and the nozzle hole position of the inkjet head;
A relative position measurement mark unit for measuring the relative positional relationship between the laser irradiator and the camera;
Control means for acquiring head alignment mark position data based on the measurement state of the camera;
A position adjustment mechanism for adjusting the position of the inkjet head based on the head alignment mark position data;
Holding means for adjusting the height and position of the inkjet head unit;
An alignment apparatus comprising:   The alignment apparatus according to claim 1, wherein the laser irradiator has an output adjustment function, and removes deposits of defective ejection nozzles by laser light irradiation, and has an ink jet head repair function.   The alignment apparatus according to claim 1, comprising a plurality of the cameras.   The alignment apparatus according to claim 1, wherein the position adjustment mechanism adjusts a position in a nozzle row direction, a height direction, and a horizontal rotation direction of the inkjet head.   The alignment apparatus according to claim 1, wherein the position adjusting mechanism adjusts the position of the inkjet head with reference to an alignment mark provided on the inkjet head unit.   The alignment apparatus according to claim 1, wherein the nozzle position data is sent to a coating apparatus to be used in a coating process.   The alignment apparatus according to claim 1, wherein the holding unit is compatible with a holding unit of a coating apparatus on which an inkjet head unit is mounted.

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