JP2007256808A - Ink jet device and discharge inspecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively inspect discharge of an ink jet head, having a plurality of head delivery holes arrayed to high density, before or after printing. <P>SOLUTION: A linear regular pattern is formed by performing printing for inspection while a metal roller is rotated to facilitate image recognition. A cleaning mechanism discharges washing liquid from a first washing liquid discharge hole upstream in the rotating direction of the metal roller and removes mixed liquid of the washing liquid and ink with a first blade, and further discharge washing liquid from a second washing liquid discharge hole and then scrapes it off with a second blade while cleaning the metal roller. Lastly, mixed liquid of washing liquid and air is jetted to the metal roller for finish washing. Then the surface of the roller is made always dry and clean by using an air knife so as to vaporize a solvent and dry the roller. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet apparatus used for forming a color pattern of a color filter, for example, and more particularly to an inspection apparatus for inspecting the discharge state of an ink discharge head of the ink jet apparatus.

Hereinafter, a color filter will be described as an example.
As a manufacturing method of a color filter (hereinafter referred to as CF) used for a liquid crystal display or the like, a photolithography method (hereinafter referred to as a photolithography method) has been generally used.
In this method, a photosensitive resist is applied to a rectangular glass substrate, and a constant lattice-like color pattern can be obtained by repeating the steps of exposure, development, and drying a plurality of times.

However, in recent years, as the size of the substrate has increased, the cost reduction of CF has become more severe as the panel price has decreased. Therefore, when constructing the next-generation CF production line exceeding 2m square by the photolithographic method, the cost of the equipment itself will be higher than the current line, and the footprint will increase due to the increased footprint due to the size increase. The initial cost is expected to increase significantly.
In addition, it can be easily predicted that the running cost will increase further due to an increase in the amount of extra ink to be developed and an increase in the amount of material used such as a developing solution, and it is difficult to satisfy the cost reduction requirement described above.

Thus, an ink ejection method has attracted attention as one of new CF manufacturing methods that can replace the photolithography method.
With this method, multiple colors are applied simultaneously to the black matrix (BM) pattern using the ink ejection head, so the exposure and development processes required for the photolithography method can be reduced, and the footprint can be reduced. Can be greatly reduced. In addition, the coating material is also the minimum amount necessary, and further, the developing solution necessary for the photolithography method is not necessary, so that the running cost can be reduced.

In such an inkjet system, as the inkjet head for ejecting ink becomes larger in size, shortens the time for improving productivity, and increases in the definition of the color filter, the heads mounted on the apparatus are densely packed. And more than one came to be arranged.
In addition, in the inkjet, non-ejection has become one of the factors that reduce the yield of products due to the ejection port clogging caused by drying of the head ejection surface and ink aggregation due to drying.
For this reason, a method has been adopted in which ink is ejected immediately before or just after ejection of the substrate to perform ejection inspection.
For example, there are a method for inspecting by ejecting the receptor layer film (for example, see Patent Document 1) and an optical inspection method for making a determination based on the light blocking state by a light projecting / receiving sensor (for example, see Patent Documents 2 and 3).
JP 2000-168106 A JP 2001-221970 A JP 2000-52542 A

However, when the receiving layer film is used, the occurrence of a film feeding error or the replacement of the film is necessary, which is a burden on the operator. In addition, the receiving layer film has a problem that it is expensive.
On the other hand, when the determination is performed by the optical inspection method, there is a problem that erroneous detection occurs, and in particular, the inspection distance is extended with respect to the densely arranged heads, which is a factor that makes inspection impossible and decreases inspection accuracy.
Further, in the case of the optical type, depending on the amount of light shielding, it is impossible to specify which ejection outlet has caused the non-ejection, which also causes a delay in countermeasures and reduces productivity.

  The present invention solves the above-described problems, and an object thereof is to effectively perform a discharge inspection before or after printing on an inkjet head having a plurality of closely arranged head discharge ports. Another object of the present invention is to provide an inkjet apparatus and a discharge inspection apparatus that can be implemented.

In order to achieve the above object, an inkjet apparatus according to the present invention includes a plurality of ink ejection heads arranged in parallel, and an inspection mechanism that inspects whether ink is ejected from all ejection ports of the ink ejection heads. The inspection mechanism includes an inspection roller having an inspection printing surface for performing a line-shaped ejection inspection pattern printing from all ejection ports of the ink ejection head, a rotation mechanism for rotating the inspection roller, And a cleaning mechanism for cleaning the ink on the inspection printing surface of the inspection roller and restoring the ink to a clean state before printing.
In addition, the present invention includes a control unit that activates and inspects the inspection mechanism before printing when printing on a product is instructed. In addition, the present invention is characterized by having a control unit that activates the inspection mechanism in accordance with a predetermined input and performs an inspection.

  The ejection inspection apparatus of the present invention is an ejection inspection apparatus for inspecting whether or not ink is ejected from all ejection ports of a plurality of ink ejection heads arranged in parallel, wherein all ejection ports of the ink ejection head An inspection roller having an inspection print surface for printing a line-shaped discharge inspection pattern, a rotating mechanism for rotating the inspection roller, and cleaning ink on the inspection print surface of the inspection roller before printing. And a cleaning mechanism for restoring to a clean state.

Further, the present invention is characterized in that the cleaning mechanism performs cleaning by providing a first cleaning liquid discharge port at an upstream portion in the rotation direction of the inspection roller and discharging the cleaning liquid from the first cleaning liquid discharge port. . Further, a first blade is provided downstream of the first cleaning liquid discharge port of the inspection roller. In addition, a mechanism for bringing the first blade into contact with and retracting from the inspection roller is provided. In addition, a second cleaning liquid discharge port is provided downstream of the first blade. In addition, a recovery unit that recovers the cleaning liquid is provided on the downstream side of the second cleaning liquid discharge port. Further, a second blade is provided on the downstream side of the collection unit. In addition, a mechanism for bringing the second blade into contact with and retracting from the inspection roller is provided. Further, a two-fluid cleaning outlet is provided on the downstream side of the second blade. Furthermore, an air knife is provided downstream of the two-fluid cleaning discharge port.
Further, the present invention is characterized in that it has an image pickup means for taking an image of the inspection print surface of the inspection roller.
The present invention can also be configured as a single discharge inspection apparatus.

  According to the ink jet apparatus and the discharge inspection apparatus of the present invention, the inspection mechanism for inspecting whether or not the ink is discharged from all the discharge ports of the ink discharge head is used for the line-shaped discharge inspection from all the discharge ports of the ink discharge head. An inspection roller having an inspection printing surface for performing pattern printing, a rotating mechanism for rotating the inspection roller, a cleaning mechanism for cleaning ink on the inspection printing surface of the inspection roller and restoring the clean state before printing Therefore, it is possible to perform an actual discharge inspection pattern printing while repeatedly restoring the inspection roller by cleaning, and to check whether ink is being discharged from all the discharge ports of the ink discharge head, It is possible to perform reliable inspection printing at a low cost and without burden on the operator, and can perform an appropriate pattern forming operation.

The embodiment of the present invention has the following features.
First, by performing inspection printing while rotating a metal roller (inspection roller), a line-shaped regular pattern is formed, and image recognition is facilitated.
In addition, as a cleaning mechanism, the cleaning liquid is discharged from the upstream side of the rotation of the metal roller by the first cleaning liquid discharge port, the mixed liquid of the cleaning liquid and the ink is removed by the first blade, and the cleaning liquid is further discharged by the second cleaning liquid discharge port. It discharges and it scrapes off with a 2nd blade, washing | cleaning on a metal roller. Finally, a mixed fluid of cleaning liquid and air is sprayed onto the metal roller to perform finish cleaning. Next, for the purpose of volatilizing and drying the solvent, an air knife is used so that the roller is always dry and the cleanliness is maintained.

  The first cleaning liquid discharge port has a function of dissolving the ink discharged from the head with the cleaning liquid, and a blade on the downstream side of the cleaning liquid discharge port has a function of preventing dry adhesion with the ink. The first blade serves to prevent the mixed liquid of the ink and the cleaning liquid discharged from the head from flowing into the second cleaning liquid discharge port located on the downstream side. Further, the first blade is held by a mechanism that retracts the first blade when performing a discharge inspection and contacts the metal roller after the inspection is completed. In addition, there is a function of discharging the cleaning liquid to the metal roller after being scraped by the second cleaning liquid discharge wave and the first blade, and cleaning.

In addition, a cleaning liquid recovery unit is provided on the downstream side of the second cleaning liquid discharge port to receive the mixed liquid of the ink and the cleaning liquid dissolved by the cleaning liquid on the metal roller and dripping.
Further, the second blade serves to scrape a mixed solution or film of the ink and the cleaning solution dissolved by the cleaning solution.
The second blade retracts the second blade when performing a discharge inspection, and contacts the metal roller after the inspection is completed.
Further, a two-fluid cleaning liquid discharge port is provided downstream of the second blade, and finish cleaning is performed by applying a striking force to the metal roller with a mixed fluid such as cleaning liquid and air. Further, an air knife is provided downstream thereof, and functions to scrape off the residual solvent on the surface of the metal roller and dry it.
Further, a camera and an illumination for imaging the surface of the metal roller are provided. After ejecting ink from the head, the head, the metal roller, a cleaning mechanism, or the like is moved to inspect pattern printing on the metal roller.

Next, the ejection inspection mechanism of the CF inkjet device according to the present embodiment will be described in detail with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing a discharge inspection mechanism of the ink jet apparatus according to the present embodiment.
The metal roller 2 is rotationally driven in the direction of arrow a by a rotation mechanism such as a motor or a speed reduction mechanism (not shown). The outer peripheral surface of the metal roller 2 is an inspection printing surface, and each means is provided so as to surround the periphery. Hereinafter, description will be made in order from the upstream side in the roller rotation direction.
In the uppermost stream, a first cleaning liquid discharge port 3 for dissolving a printed pattern after printing for discharge inspection on the metal roller 2 by the head 1 is provided.
The first blade 4 is blocked so that the mixed liquid of the ink and the cleaning liquid does not flow into the second cleaning liquid discharge port 5 disposed further downstream on the downstream side. The liquid flows along the upper surface of the blade 4 to the waste liquid line.

Further, as described above, the cleaning liquid discharge port 5 is provided on the downstream side of the blade 4, and the metal roller 2 is discharged by cleaning the metal roller 2. Then, the cleaning droplets hanging from the metal roller 2 are received by the receiving pan 6. The cleaning liquid drained on the receiving pan 6 can be reused for cleaning the uppermost roller 2.
A second blade 7 is installed on the downstream side of the receiving pan 6, and the cleaning liquid on the surface of the metal roller 2 cleaned at the cleaning liquid discharge port 5 is scraped off to the pan 6 side.
On the downstream side, a final finishing is performed by applying a striking force to the metal roller 2 through a two-fluid cleaning discharge port 8 of a mixed fluid such as cleaning liquid and air. Further, an air knife 9 is installed downstream, and the cleaning liquid adhering to the metal roller 2 is scraped off and dried, so that the metal roller 2 is always kept at a high cleanliness.

  The mechanism described above is unitized, and the moving mechanism moves between the print position where printing is performed by the head 1 and the inspection position where inspection is performed, thereby automatically performing inspection printing work and inspection work. To do. Further, the blades 4 and 7 are provided with a mechanism for contacting and retracting the roller 2 so that the blades 4 and 7 are displaced in synchronization with the discharge operation of the cleaning liquid.

Next, the operation will be described.
FIG. 2 shows a state where the inspection unit has moved to the inspection position. 3 and 4 show a state in which the inspection printing surface of the metal roller is exposed on the upper part of the inspection unit, FIG. 3 shows a state before printing, and FIG. 4 shows a state after printing. Yes.

  First, in order to perform a discharge inspection before product printing, a discharge inspection command is output. The inspection printing unit moves directly below the head 1. At that time, when the metal roller 2 starts to rotate in the right direction in the drawing, the head 1 performs printing at the same time. During rotation of the metal roller 2 during printing, the blade 4 and the blade 7 are in the retracted state, and the cleaning liquid is not discharged. Then, when the pattern printing 12 for a certain set time is completed, the rotation of the metal roller 2 is stopped and moved to the inspection position shown in FIG.

In this inspection position, for example, image recognition by reflection having the illumination 11 and the camera 10 is performed, omission of regular pattern printing, bending of a printing line, and the like are determined by image processing, and an OK / NG determination result is output. . If the determination result is OK, the head starts product printing, and if it is NG, the head discharge recovery operation is performed by head maintenance (description is omitted). In the case of OK, the blades 4 and 7 are in contact with the metal roller 2, and while rotating the roller 2, the process of ink dissolution → doctoring → cleaning → doctoring → precision cleaning → drying is performed to clean the metal roller 2. In preparation for the next discharge inspection.
In the above example, the case where the ejection inspection is performed before product printing has been described, but in other cases, the inspection operation can be arbitrarily designated and executed by a specific key input or the like.
In addition, it is assumed that specific values such as materials of components such as rollers and blades, cleaning liquid, discharge conditions, and the number of times of cleaning can be appropriately selected in actual design.

It is a schematic sectional drawing which shows the discharge inspection mechanism of the inkjet apparatus which concerns on embodiment of this invention. It is a schematic sectional drawing which shows the state which the unit for an inspection shown in FIG. 1 moved to the inspection position. It is a top view which shows the test | inspection printing surface before printing of the metal roller of the unit for an inspection shown in FIG. It is a top view which shows the test | inspection printing surface after printing of the metal roller of the unit for an inspection shown in FIG.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 1 ... Inkjet head, 2 ... Metal roller, 3, 5 ... Cleaning liquid discharge port, 4, 7 ... Blade, 5 ... Cleaning liquid discharge port, 6 ... Cleaning liquid receiving pan, 8 ... Two fluid cleaning port, 9 ... Air knife, 10 ... Camera, 11 ... Lighting.

Claims (24)

A plurality of ink ejection heads arranged in parallel, and an inspection mechanism for inspecting whether or not ink is ejected from all ejection ports of the ink ejection head,
The inspection mechanism is
An inspection roller having an inspection printing surface that performs line-shaped ejection inspection pattern printing from all the ejection openings of the ink ejection head;
A rotating mechanism for rotating the inspection roller;
A cleaning mechanism that cleans the ink on the inspection printing surface of the inspection roller and restores it to a clean state before printing;
An inkjet apparatus comprising:   2. The ink jet apparatus according to claim 1, further comprising a control unit that activates and inspects the inspection mechanism before printing when printing on a product is instructed.   The inkjet apparatus according to claim 1, further comprising a control unit that activates the inspection mechanism in response to a predetermined input to perform an inspection.   2. The cleaning mechanism according to claim 1, wherein the cleaning mechanism is provided with a first cleaning liquid discharge port at an upstream portion in a rotation direction of the inspection roller, and cleaning is performed by discharging the cleaning liquid from the first cleaning liquid discharge port. Inkjet device.   The inkjet apparatus according to claim 4, wherein a first blade is provided downstream of the first cleaning liquid discharge port of the inspection roller.   6. The ink jet apparatus according to claim 5, further comprising a mechanism for bringing the first blade into contact with and retracting from the inspection roller.   The inkjet apparatus according to claim 5, wherein a second cleaning liquid discharge port is provided downstream of the first blade.   The ink jet apparatus according to claim 7, wherein a recovery unit that recovers the cleaning liquid is provided on the downstream side of the second cleaning liquid discharge port.   The inkjet apparatus according to claim 8, wherein a second blade is provided downstream of the collection unit.   The inkjet apparatus according to claim 9, further comprising a mechanism for bringing the second blade into contact with and retracting from the inspection roller.   The inkjet apparatus according to claim 10, wherein a two-fluid cleaning discharge port is provided downstream of the second blade.   The inkjet apparatus according to claim 11, wherein an air knife is provided downstream of the two-fluid cleaning discharge port.   The inkjet apparatus according to claim 1, further comprising an imaging unit that captures an image of an inspection printing surface of the inspection roller. A discharge inspection apparatus for inspecting whether or not ink is discharged from all discharge ports of a plurality of ink discharge heads arranged in parallel,
An inspection roller having an inspection printing surface that performs line-shaped ejection inspection pattern printing from all the ejection openings of the ink ejection head;
A rotating mechanism for rotating the inspection roller;
A cleaning mechanism that cleans the ink on the inspection printing surface of the inspection roller and restores it to a clean state before printing;
A discharge inspection apparatus comprising:   15. The cleaning mechanism according to claim 14, wherein a first cleaning liquid discharge port is provided in an upstream portion in the rotation direction of the inspection roller, and cleaning is performed by discharging the cleaning liquid from the first cleaning liquid discharge port. Discharge inspection device.   The discharge inspection apparatus according to claim 15, wherein a first blade is provided downstream of the first cleaning liquid discharge port of the inspection roller.   The discharge inspection apparatus according to claim 16, further comprising a mechanism for contacting and retracting the first blade with respect to the inspection roller.   The discharge inspection apparatus according to claim 16, wherein a second cleaning liquid discharge port is provided downstream of the first blade.   The discharge inspection apparatus according to claim 18, wherein a recovery unit that recovers the cleaning liquid is provided downstream of the second cleaning liquid discharge port.   The discharge inspection apparatus according to claim 19, wherein a second blade is provided downstream of the collection unit.   21. A discharge inspection apparatus according to claim 20, further comprising a mechanism for bringing the second blade into contact with and retracting from the inspection roller.   21. The discharge inspection apparatus according to claim 20, wherein a two-fluid cleaning discharge port is provided downstream of the second blade.   The discharge inspection apparatus according to claim 22, wherein an air knife is provided downstream from the two-fluid cleaning discharge port.   The ejection inspection apparatus according to any one of claims 14 to 23, further comprising an imaging unit that captures an image of an inspection printing surface of the inspection roller.

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