JP2007260571A - Alignment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alignment apparatus which can perform alignment of inkjet heads by a function independent of an application apparatus and which can sharply reduce arrangement time when performing application. <P>SOLUTION: An alignment mark is attached to an inkjet head unit. The alignment mark is detected and further coordinates of a nozzle hole of each head (nozzle position data) are detected and heads are aligned by using a fine adjustment mechanism and attitude of each inkjet head is held. Then positional information from the alignment mark is sent to the application apparatus so as to be utilized and arrangement time of application is sharply reduced. <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 was repeated 3 times and R.D. G. B. This is a method for obtaining a color filter layer.
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 was repeated three times and R.P. G. B. The color filter layer is obtained. 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) In the printing method, a pigment is dispersed in a thermosetting resin, and printing is repeated three times. G. B. And then applying heat to cure the resin to obtain a color filter layer. This method is described in R.A. G. B. Photolithography is not required for forming the layer, but there is 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. And repeating this three times, R.M. G. B. The color filter layer is obtained. 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.

  In this color filter manufacturing apparatus using the ink jet system, a recording medium and an ink jet head in which a plurality of nozzles are linearly arranged for each color of R, G, B or Y, M, and C are relatively reciprocated in the main scanning direction. And a recording medium feeding means that intermittently feeds a set amount in the sub-scanning direction. While moving the ink-jet head in the main scanning direction, ink is pressurized from the head to the recording medium by a pressure generator with a predetermined pressure. Then, 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 ejecting onto a large recording medium, since the ink jet head is reciprocated many times when the ejection width of the ink jet head is narrow, it is necessary to arrange a number of ink jet heads in order to reduce 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.

  Accordingly, an object of the present invention is to provide an alignment apparatus that can perform alignment of an inkjet head by a function independent of the coating apparatus, and can greatly reduce the setup time during coating.

  In order to achieve the above object, an alignment apparatus of the present invention includes a camera that measures the position of a nozzle hole of an inkjet head provided in the inkjet head unit, and a control that acquires nozzle position data based on the measurement state of the camera. And a position adjusting mechanism for adjusting the position of the ink jet head based on the nozzle position data.

  According to the alignment apparatus of the present invention, an efficient operation can be performed by performing an alignment operation of the inkjet head, which has been conventionally performed on the coating apparatus, by a dedicated alignment apparatus different from the coating apparatus. This has the effect of significantly reducing the setup time during coating.

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. The present invention provides an alignment apparatus that has a simple inkjet head arrangement and can prevent a reduction in the operating rate of the coating apparatus.
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, an alignment mark is attached to the ink jet head unit. The alignment mark is detected, the coordinates of the nozzle holes (nozzle position data) of each head are detected, and the head is adjusted using a fine adjustment mechanism. Align and hold the posture of each inkjet head. Then, position information (nozzle position data) from the 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.

Next, prior to the description of the alignment apparatus that is a feature of the present embodiment, a coating apparatus that can be used in combination with this alignment apparatus will be described.
FIG. 2 is an external view showing an outline of an inkjet color filter manufacturing apparatus (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 discharge timing during the drawing operation is that the substrate stage moves in the main scanning direction, and ink is discharged 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.
The color filter is 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 and coloring the transparent layer. For example, there is a method of applying ink to a bank having a black matrix habitability and 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. Reference numeral 7 denotes an R ink droplet, 8 denotes a G ink droplet, and 9 denotes a B ink droplet. In this example, in order to form the colored portions of R, G, and B, three ink jet heads must be used and applied to the ink droplets corresponding to the 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. Considering the variation in the output, the tolerance of the ink jet head 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 this embodiment will be described.
FIG. 1 is an external view showing the configuration of the inkjet head alignment apparatus of 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. A nozzle array formed of a plurality of nozzles is provided on the nozzle formation surface of the inkjet head.
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.
Two nozzle hole observation cameras 12 are installed on the stage 11 of the alignment apparatus. In addition, since there are two nozzle hole observation cameras 12, it is possible to simultaneously observe two nozzle hole positions of the inkjet head. That is, it is very advantageous to adjust the X direction and the Y direction of the inkjet head by observing the two nozzle holes.

The X direction slider 13 and the Y direction slider 14 move the camera when observing the nozzle surface of the inkjet head. 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 nozzle hole observation display 17 displays images from the two cameras 12, and shows a reticle or the like on the screen and is used to align the nozzle holes.

  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.

1 is an external view showing an alignment apparatus according to an embodiment of the present invention. It is an external view which shows an example of a coating device. It is explanatory drawing which shows the drawing method of a color filter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Inkjet head unit, 10 ... Inkjet head, 11 ... Stage, 12 ... Nozzle hole observation camera, 13 ... X-direction slider 3, 14 ... Y-direction slider, 15 ... Isolation table, 16 ...... Head unit holder, 17 ... Nozzle hole observation display, 18 ... Alignment control panel, 19 ... Controller, 20 ... Motor switching BOX.

Claims (6)

A camera for measuring the position of the nozzle hole of the inkjet head provided in the inkjet head unit;
Control means for acquiring nozzle 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 nozzle 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 a plurality of the cameras are provided.   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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