KR20080088756A - Non-contact type head cleaner for ink-jet printer - Google Patents

Abstract

A non-contact type head cleaner for an ink-jet printer is provided to prevent damage to a hydrophobic coating layer on the surface of a head by forming a cleaning unit for removing washing liquid on a nozzle outlet of a head. A non-contact type head cleaner for an ink-jet printer comprises a head driving part for raising a head(10), a cleaning tub, and a cleaning unit(60). The cleaning tub contains washing liquid to dip a nozzle outlet of the head moved downward by the head driving part into the washing liquid. The cleaning unit removes the washing liquid on the nozzle outlet of the head by spraying gas to form an air current and re-sucking the air current to the head floated after dipped into the washing tub.

Description

Non-contact type head cleaner for ink-jet printer

1 is a schematic configuration diagram of an inkjet printer head cleaning device for forming a conventional contact color filter.

Figure 2 is a schematic block diagram schematically showing the configuration of a non-contact inkjet printer head cleaning device according to the present invention.

Figure 3 is an operating state diagram showing the process of removing and drying the residual cleaning liquid of the head performed by the cleaning unit applied to the present invention.

* Description of the symbols for the main parts of the drawings *

10: Head 11: Nozzle

40: head drive part 50: cleaning tank

51: washing liquid 60: washing unit

62: injection hole 64: suction hole

70: vacuum pump 73: position detection sensor

74: control unit

The present invention relates to a head cleaning device for an ink jet printer for forming a color filter, and more particularly, to a head cleaning device for a non-contact ink jet printer for cleaning the head in a non-contact manner to prevent damage to the hydrophobic coating film coated on the surface of the head. will be.

An inkjet printer for forming a color filter is generally used as an apparatus for manufacturing a color filter by printing RGB colors in a pixel area defined by a black matrix pattern on a glass substrate. The inkjet printer for forming a color filter has an advantage of greatly reducing the color filter process step compared to the conventional method, and thus has been widely used in substrate coating.

The color filter forming inkjet printer forms a color layer in the pixel area while a head having a plurality of nozzles moves on a large glass substrate. In the case of continuously forming color layers on the surface of a plurality of glass substrates using such an inkjet printer, during the waiting time for the next coating, the chemical liquid remaining at the tip of the nozzle is exposed to the outside air and cured so that a part of the nozzle is blocked. You can issue. If coating is continued on the next glass substrate in this state, a good coating layer cannot be formed.

In order to prevent such nozzle clogging, the head has been conventionally cleaned by using a soft cleaning means containing a cleaning liquid. Thus, the head cleaning device of the inkjet printer for forming a conventional color filter is attached. Let's look at it briefly.

1 is a schematic configuration diagram of an ink jet printer head cleaning device for forming a conventional color filter.

Referring to FIG. 1, a conventional inkjet printer includes a head 10 for discharging ink and a contact cleaner 20 for contact cleaning the head 10 using a cleaning liquid.

Specifically, the head 10 includes a plurality of nozzles 11 for ink ejection, and the hydrophobic coating layer 12 is formed on the surface of the head 10. The hydrophobic coating layer 12 is intended to induce good ejection because the ink discharged from the nozzle 11 is easily detached from the surface of the head 10. Particularly, the hydrophobic coating layer 12 is always provided at the periphery of the nozzle 11. It must be formed so that ink droplets can be ejected to a desired position.

The nozzle 11 is a discharge hole through which ink for printing a color layer of a color filter is directly discharged, and is a fine hole having a diameter of unit pixel or less. Therefore, in the process of ejecting the ink and waiting, the ink may be cured and the nozzle 11 may be blocked. When the nozzle 11 is blocked, the reliability of the process may be deteriorated, such as no color layer is formed on a specific pixel, Degrading problems may occur.

In order to prevent this, a contact cleaner 20 for periodically cleaning the head 10 is provided around the head of the inkjet printer for forming a conventional color filter. The contact cleaner 20 is made of a soft material that does not damage the head 10 and contains a cleaning liquid such as a solvent or pure water for the color filter forming ink.

As such, conventionally, contact cleaning is performed on the head by using the contact cleaner 20 moving along the head. In this case, the hydrophobic coating layer 12 may be damaged during the cleaning process, and in particular, a portion adjacent to the nozzle 11 to which the side surface is exposed may be easily damaged. When ink is discharged through the nozzle 11 while the hydrophobic coating layer 12 is damaged as described above, a part of the discharged ink is damaged by the hydrophobic coating layer 12, and thus the head of the side surface of the nozzle 11 exposed. Buried in 10, the droplet 30 remains.

Furthermore, when the ink droplets 30 remain in the periphery of the nozzle 11 as described above, when ink is discharged again through the nozzles 11, the droplets 30 prevent the ink from being discharged, thereby making accurate discharge. There is a problem that it is not possible to perform the correct color filter manufacturing process, such as the droplet 30 is scattered and printed on the pixel area of a different color to cause color bleeding phenomenon.

The present invention has been made in view of the above-described problems of the prior art, while periodically cleaning the head of the color-jet inkjet printer for forming a non-contact, which can prevent damage to the hydrophobic coating film coated on the surface of the head It is an object to provide a head cleaning device for a non-contact inkjet printer.

In order to achieve the above object, the present invention, the head hole for elevating the head, and the cleaning tank for accommodating the cleaning liquid so that the nozzle discharge port of the head moved downward by the drive of the head drive unit, and the cleaning tank, It provides a head cleaning apparatus for a non-contact inkjet printer comprising a; cleaning unit for spraying gas to the floating head after being immersed to form an air flow and suction it again to remove the cleaning liquid remaining in the nozzle discharge port of the head.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic structural diagram of a cleaning apparatus of a non-contact inkjet printer head according to an embodiment of the present invention. Prior to describing the present invention, the same components and reference numerals will be given to the same components as in the conventional configurations.

 Referring to FIG. 2, the head cleaning device includes a head driving unit 40 for raising and lowering the head 10 and a washing tank 50 for cleaning the head 10 moved downward by the head driving unit 40. And a cleaning unit 60 for removing the cleaning liquid remaining in the bottom surface of the head 10 after cleaning through the cleaning tank. The cleaning tank 50 accommodates the cleaning liquid 51 therein for the head cleaning, and the cleaning unit 60 injects gas to clean the nozzle 50 through the cleaning tank 50 and then discharges the nozzles of the head 10. The washing | cleaning liquid which remain | survives in is dried and removed. The main part configuration of the present invention will be described in more detail.

The head driver 40 includes a lifting device (not shown) for lifting the head up and down. The elevating device may be, for example, a lift type lifting means by a hydraulic / pneumatic cylinder, or alternatively, a general lift type lifting means including a hoisting roll and a wire. In addition to this, any configuration can be used as long as the head is raised and lowered.

The cleaning tank 50 is in the form of a container with an open top, and houses the cleaning liquid 51 for cleaning therein. As described above, the cleaning tank 50 is disposed directly below the head 10 to clean the head 10 moved downward by the head driver 40. That is, when a part of the bottom surface of the head 10 is moved to the position where the head 10 is immersed in the cleaning liquid 51 filled in the cleaning tank 50, the cleaning liquid 51 filled in the cleaning tank 50 is moved. ), The nozzle, specifically, the nozzle discharge port formed in the head 10 is cleaned.

As the cleaning liquid 51 as described above, a solvent or deionized water for the color filter forming ink may be used, and preferably, a solvent of the ink is used to enable non-contact cleaning.

Preferably, the head drive 40 may include a vibration means (not shown). The vibration means may be a form in which a vibration device having a motor and an eccentric cam is installed in the head driving unit, and a vibration device including a motor and an eccentric cam is provided outside the head driving unit to vibrate the head driving unit. . When the vibrating means is provided in the head driving unit as described above, the contact between the cleaning liquid 51 and the head 10 can be given a slight vibrating contact rather than a simple contact, so that more efficient cleaning can be performed.

The cleaning unit 60 has an injection hole 62 for injecting an inert gas such as N _{2 and} Ar at high pressure in the center of a substantially cylindrical main body (not shown). It has a plurality of suction holes 64 disposed at equal intervals along the circumferential direction. The injection hole 62 injects the gas at a high pressure toward the head, preferably at a blowing pressure / vantury pressure of 30 kpa or more to separate the foreign matter and the cleaning liquid on the head, and the suction hole 64 is the gas. The foreign matter and the cleaning liquid separated from the head are sucked and exhausted by the suction.

Here, when the gas is injected in a direction coinciding with the nozzle of the head facing the injection direction of the gas injected from the injection hole 62, the foreign matter and cleaning liquid remaining on the air and the bottom of the head is reversed to the nozzle side. There is a risk of inflow. For this reason, although the injection hole 62 is illustrated in the drawing to be formed vertically in accordance with the nozzle 11 forming direction, the injection hole 62 is configured to have a tilt angle inclined in one direction with respect to the nozzle 11 of the head. It is preferable to.

In addition, it is preferable that the suction hole 64 has a venturi structure where the cross section of the central portion C is sharply narrower than that of the inlet through which the circulating gas and the head-side residual cleaning liquid 51a flow. In this case, due to the increase in the gas velocity in the central portion (C), the static pressure of the portion is reduced, so that the speed of the gas flowing into the inlet side of the suction hole 64 can be faster. That is, when the suction hole 64 has a bantry structure, it is possible to exhaust the gas and the cleaning liquid exhausted at a higher speed.

The cleaning unit 60 as described above is preferably, by the position detection sensor 73 for detecting the injured position of the head 10 and the control unit 74 for controlling the operation according to the detection signal detected from the sensor The operation is controlled. In this case, when the head 10 is injured from the cleaning tank 50 after cleaning, the position detection sensor 73 immediately detects the injured position, and the control unit 74 calculates the detected signal to the cleaning unit 60. Immediately start the vacuum pump 70 to generate strong injection and suction force. That is, after the head cleaning through the cleaning tank, the drying and cleaning operations for the cleaning liquid remaining in the nozzle discharge port of the head can proceed immediately.

In addition, the cleaning unit 60 may be configured to be moved to a position close to the bottom of the head by a moving substrate not shown in the drawing. The moving substrate may be configured to include an X-axis driving unit for horizontally moving the cleaning unit and a Y-axis driving unit for vertically moving the cleaning unit. In this case, the position of the cleaning unit 60 can be easily placed close to the nozzle discharge port side of the head 10, so that the drying efficiency of the nozzle discharge port of the head 10 can be further improved.

The head cleaning process of the inkjet printer for color filter formation performed by using the cleaning apparatus of the present invention having the above-described configuration will be described in connection with the operation of the present invention.

Inkjet printer heads for color filter formation require cleaning of the head in the middle for good color filter formation in subsequent subsequent coatings. The cleaning is done after the coating with a waiting time for the next coating. In order to perform such cleaning, the head moves to the cleaning apparatus of the present invention at the waiting time, and thus, a full cleaning operation is performed on the head.

Specifically, the head 10 having the color filter coating layer formed on the glass substrate moves to the cleaning tank 50 for cleaning and is positioned above the cleaning tank 50. In this state, when the head 10 moves downward toward the cleaning tank 50 by the driving of the head driving unit 40, and moves to a position where a part of the bottom surface of the head is immersed in the cleaning liquid 51 filled in the cleaning tank 50. The movement stops. Then, the cleaning of the head, specifically, the discharge port of the nozzle 11 at the bottom of the head is performed through the cleaning liquid 51 filled in the cleaning tank 50.

When a predetermined time elapses while a part of the head 10 is immersed in the cleaning liquid 51, the head 10 rises again from the cleaning tank 50 due to the operation of the head driving unit 40. When the position of the head 10 reaches the peak, the position detecting sensor 73 detects this and the vacuum pump 70 is operated so that the foreign matter remaining on the secondary cleaning of the head through the cleaning unit 60 and the nozzle discharge port and Drying to the cleaning liquid 51a advances.

The head cleaning and drying process performed through the cleaning unit 60 will be described in more detail with reference to the accompanying drawings.

3 is a view illustrating an operation state showing a process of removing and drying residual foreign substances and cleaning liquid of the head by the cleaning unit in the cleaning apparatus according to the present invention.

Referring to FIG. 3, high pressure is injected through the injection hole 62 of the cleaning unit 60 toward the nozzle discharge port of the head 10 facing inert gas such as N _{2 and} Ar. At the same time, through the suction hole 64, the intake / exhaust of the gas injected to the outside through the injection hole 62 is simultaneously performed. Therefore, the circulating air flow as the arrow of a figure is formed in the nozzle discharge port side of the head 10. As shown in FIG.

The foreign matter and the cleaning liquid 51a are separated from the head and flow into the suction hole 64 at the nozzle discharge port of the head 10 by the airflow. That is, the foreign matter and the cleaning liquid (including the remaining ink, 51a) remaining in the nozzle 11 discharge port of the head 10 are detached from the head 10 due to the injection of the high pressure gas through the injection hole 62, The foreign matter and the cleaning liquid 51a are introduced into the suction hole 64 by the suction force of the suction hole 64 and discharged to the outside through the suction hole 64.

Here, the suction hole 64 has a venturi structure where the cross section of the central portion C is sharply narrower than that of the inlet through which the circulating gas and the head side residual cleaning liquid 51a flow. Therefore, the velocity of the gas sucked in the central portion (C) increases, so that the static pressure of that portion decreases. As a result, due to the pressure difference between the inlet and the central portion of the suction hole 64, the gas (including the cleaning liquid and residual ink) flowing into the inlet side can be introduced at a higher speed. As a result, the gas and the cleaning liquid exhausted through the suction hole 64 can be exhausted at a higher speed by the Bantry principle, and the removal efficiency of the residual cleaning liquid (including the residual ink) can be further improved.

The head cleaning operation through the cleaning unit 60 as described above may proceed in conjunction with the cleaning of the head 10 by the cleaning tank 50 as described above, alternatively, may be performed alone in the waiting time for coating. . In this case, only the above-described moving base for approaching the cleaning unit 60 to the head side is required, and the head driving unit and the cleaning tank may be omitted.

In addition, the cleaning unit 60 configured and operated as described above may be used alone or as one shown in the drawings, but not shown in the drawings.

According to the embodiment of the present invention, a strong circulating air flow is formed on the nozzle discharge port side of the head 10 by the cleaning unit 60 applying the bancho principle, and using this to clean the head 10 in a non-contact manner The work is done. Therefore, damage to the hydrophobic coating layer coated on the surface of the head 10 is essentially prevented, and no droplets remain around the nozzle 11 of the head by the strong circulation airflow. As a result, it is possible to form a better color filter coating layer when forming the color filter later.

The present invention has been shown and described with reference to certain preferred embodiments, but the present invention is not limited to the above-described embodiments and has ordinary skill in the art to which the present invention pertains without departing from the concept of the present invention. Various changes and modifications are possible by the user.

As described above, according to the non-contact inkjet head cleaning apparatus of the present invention, by cleaning the inkjet printer head in a non-contact manner, it is possible to prevent the hydrophobic coating layer on the surface of the head from being damaged and thus to maintain ink droplets around the nozzle. You can prevent it. As a result, it is possible to improve the manufacturing process reliability of the color filter and to prevent a decrease in the yield of the color filter.

Claims (9)

A head driving unit for elevating the head; A cleaning tank accommodating the cleaning liquid so that the nozzle discharge port of the head moved downward by the head driving unit is immersed in the cleaning liquid; And And a cleaning unit for spraying gas to the floating head after being immersed in the cleaning tank to form an air flow, and sucking it again to remove the cleaning liquid remaining in the nozzle discharge port of the head. The method of claim 1, A sensor for detecting a position of the head injured by the head driving unit; And If the position of the head detected by the sensor is a control position, the control unit for controlling the operation of the cleaning unit for supplying gas to the head; head cleaning apparatus of a non-contact inkjet printer further comprising. The method according to claim 1 or 2, The head drive unit head cleaning apparatus of the non-contact inkjet printer, characterized in that it comprises a vibration means. The method of claim 1, The cleaning unit, An injection hole for injecting gas toward the head to separate the foreign matter and the cleaning liquid from the head; And a suction hole formed to be spaced apart from the injection hole by a predetermined distance to suck and discharge the foreign matter and the cleaning liquid separated by the gas. The method of claim 4, wherein And the ejection hole has an inclined angle inclined in one direction with respect to the nozzle of the head such that the gas ejection direction ejected from the ejection hole does not coincide with the head nozzle facing the nozzle. The method of claim 4, wherein The suction hole is a head cleaning device of a non-contact inkjet printer, characterized in that the venturi structure has a narrow narrow cross section in the center portion compared to the inlet. The method according to claim 1 or 4, The gas is a head cleaning device for a non-contact inkjet printer, characterized in that N ₂ or Ar gas. The method according to claim 1 or 4, The cleaning unit is a head cleaning apparatus of a non-contact inkjet printer, characterized in that the movable base is configured to be moved to a close position facing the bottom of the head. The method of claim 8, The mobile base is, An X-axis driving unit for horizontally moving the cleaning unit, and a Y-axis driving unit for vertically moving the cleaning unit, the head cleaning apparatus of a non-contact inkjet printer.

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