TW201700307A - Apparatus for ink drying prevention capable of preventing ink from drying in the nozzle even when the solvent or the like evaporates with the passage of time - Google Patents

Abstract

The present invention provides an apparatus for ink drying prevention that prevents ink from drying in the nozzle, even when the solvent or the like evaporates with the passage of time. According to this invention, an apparatus for ink drying prevention is presented. That is ejected from a coating head with a plurality of nozzles for ejecting ink drying. The apparatus comprising: a washing tray formed with a solvent storage unit for storing a solvent of ink, and a porous member, which is disposed, so as to be immersed in a solvent storage unit of the washing tray and contains a solvent of ink, and the porous member has a nozzle-facing surface opposed to the nozzle, and the height of the porous member is set in the following manner: the front end of the nozzle is positioned in a solvent atmosphere formed between the nozzle facing surface and the front end of the nozzle, making it suitable for preventing the ink from drying in a state of the coating head being positioned above the processing tray.

Description

Anti-ink drying device

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an ink-jet preventing apparatus for preventing ink drying in a coating head for ejecting ink from an ink-jet coating apparatus that ejects ink from a plurality of nozzles.

A color filter is used in a flat panel display such as a color liquid crystal display. This color filter is efficiently produced by an inkjet coating device or the like. The inkjet coating device has a coating head including a plurality of nozzles, and is capable of ejecting various inks to a specific position with high precision.

For example, the formation of a color filter is performed by applying ink of three colors to a substrate such as glass with high precision in a specific pattern. In order to form a color filter with high precision and good quality, it is necessary to appropriately store the ink in the nozzle (ink in the nozzle that is in contact with the atmosphere). That is, if the ink in the nozzle is dried, the viscosity of the ink is increased to affect the flight of the ink, or the ink solidified by drying is dropped onto the substrate, etc., which brings a large color filter to a high quality. The impact. Therefore, when the coating operation is not performed for a predetermined period of time such as replacement of the substrate, the coating head is placed in the ink drying prevention device, and the ink is dried by the coating head by performing the rinsing operation.

As shown in FIG. 5, the ink-preventing drying device is provided with a washing tray 101 that receives ink ejected from the coating head 100. A solvent storage unit 102 that stores ink or a solvent constituting the ink (referred to as a solvent or the like) is formed in the rinsing tray 101. Further, when the coating operation is not performed for a certain period of time, the coating head 100 is placed on the solvent storage portion 102 of the rinse tray 101 to prevent the respective nozzles of the coating head 100 from drying. That is, in the solvent storage unit 102, a certain solvent vapor pressure is formed by a solvent or the like evaporated from the solvent storage unit 102. In the solvent atmosphere SB, by disposing all the nozzles in the solvent atmosphere SB, it is possible to prevent the ink of each nozzle from drying (see, for example, Patent Document 1 below).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2011-036798

However, in the above-described ink drying preventing device, there is a problem that the ink cannot be completely prevented from drying. In other words, the ink drying prevention device is placed on the solvent storage unit 102, and the nozzle is placed at a height position of a specific solvent atmosphere SB capable of preventing drying of the solvent vapor pressure (appropriate solvent vapor pressure), thereby preventing drying.

However, as shown in Fig. 6, the liquid level of the solvent or the like changes due to evaporation of the solvent or the like. Therefore, the nozzle which is initially located in the specific solvent atmosphere SB leaves the solvent atmosphere SB of the appropriate solvent vapor pressure over time, so that it is not suitable. The drying is prevented from causing the ink in the nozzle to dry, whereby there is a problem that the unsprayed or the ejection speed is lowered.

The present invention has been made in view of the above problems, and it is an object of the invention to provide an ink drying preventing apparatus capable of preventing drying of ink in a nozzle even if evaporation of a solvent or the like progresses with time.

In order to solve the above problems, the ink drying prevention device of the present invention is characterized in that it is an ink dryer for preventing a coating head having a plurality of nozzles for ejecting ink, and comprises: a rinsing tray formed with a solvent for storing the ink. a solvent storage unit; and a porous member which is disposed in a state of being immersed in a solvent storage portion of the rinse tray and containing a solvent of the ink; and the porous member has a nozzle facing surface opposite to the nozzle, the porous The height of the mass member is set in such a manner that in the state in which the coating head is located on the flushing tray, the front end of the nozzle is located on the opposite surface of the nozzle. Within the specific solvent atmosphere between the front ends of the nozzles.

According to the above-described ink drying prevention device, a porous member containing a solvent of ink is disposed in the rinse tray, and the nozzle is disposed in a specific solvent atmosphere formed on the nozzle facing surface of the porous member, so that the nozzle can be prevented from being inside. The ink is dry. That is, since the shape of the porous member does not change over time, it is possible to suppress the change in the distance between the nozzle facing surface of the porous member and the tip end of the nozzle with time. In other words, the solvent is absorbed in the porous member, and the distance between the solvent absorbed by the porous member and the tip end of the nozzle is maintained constant even with the passage of time. Therefore, the solvent atmosphere of the tip end portion of the nozzle when the nozzle tip is initially disposed can be used. After a certain period of time, the solvent atmosphere of the tip end portion of the nozzle is suppressed to be substantially the same solvent atmosphere. Therefore, the change in the solvent atmosphere at the tip end of the nozzle can be suppressed as compared with the conventional ink-repellent drying device in which the liquid level changes with time, so that drying of the ink in the nozzle can be suppressed.

Moreover, the nozzle opposing surface may be formed of a solvent film formed on the porous member.

According to this configuration, since the solvent film is formed on the porous member, a sufficient solvent atmosphere can be formed, and drying of the ink in the nozzle can be further suppressed.

Further, it is preferable that the porous member has an open cell structure.

According to this configuration, when the solvent or the like stored in the rinse tray is absorbed by the porous member, the absorbed solvent or the like easily moves in the porous member by the continuous bubbles. Therefore, even if the evaporation of the solvent or the like progresses with time, since the absorbed solvent or the like moves toward the nozzle opposing surface, it is easy to continuously form a solvent atmosphere on the nozzle opposing surface. Therefore, the effect of preventing the ink in the nozzle from drying can be maintained for a long period of time.

According to the ink-preventing apparatus of the present invention, even if the evaporation of the solvent or the like advances with time, the ink in the nozzle can be prevented from drying.

1‧‧‧Inkjet coating device

2‧‧‧ platform

3‧‧‧ Coating unit

4‧‧‧Anti-ink drying device

5‧‧‧ head module

10‧‧‧Substrate

21‧‧‧ Track

31‧‧‧ head unit

32‧‧‧ bracket

32a‧‧‧Support components

32b‧‧ ‧ Beam Department

41‧‧‧Abutment

42‧‧‧ rinse tray

44‧‧‧Solvent storage department

46‧‧‧Porous components

46a‧‧‧Nozzle facing

51‧‧‧Coating head

51a‧‧・Nozzle surface

100‧‧‧Coating head

101‧‧‧ rinse tray

102‧‧‧Solvent Storage Department

SB‧‧‧ solvent atmosphere

X‧‧‧ axis

Y‧‧‧ axis

Z‧‧‧ axis

Fig. 1 is a side view schematically showing an inkjet coating apparatus including an ink drying device according to an embodiment of the present invention.

Fig. 2 is a front view schematically showing the above inkjet coating device.

Fig. 3 is a front view schematically showing the above-described ink drying preventing device and the head unit.

Fig. 4 is a view schematically showing a flushing tray and a head module.

Fig. 5 is a view showing a conventional ink drying preventing device.

Fig. 6 is a view showing a state in which the solvent or the like in the rinsing tray is reduced in the conventional ink-preventing apparatus.

An embodiment of the ink-preventing apparatus of the present invention will be described with reference to the drawings.

1 is a side view showing an embodiment of an inkjet coating device having an ink drying preventing device, FIG. 2 is a front view of the inkjet coating device, and FIG. 3 is a front view showing the ink drying preventing device and the head unit, FIG. A diagram schematically showing the flushing tray and the head module. In the present embodiment, the ink in the case where the ink of the inkjet coating device is used as the color filter is described. However, the ink is electrically conductive (Electroluminescence) or wiring pattern. If the ink or the like can be ejected in the form of an inkjet, it is possible to target all the inks.

In FIGS. 1 to 4, the inkjet coating apparatus 1 can produce, for example, a flat panel for a color liquid crystal display by ejecting various inks of R (red), G (green), and B (blue) onto the substrate 10. Color filter for the display. As shown in FIGS. 1 and 2, the inkjet coating apparatus 1 has a stage 2 on which a substrate 10 is placed, and an application unit 3 that applies ink to the substrate 10. The coating unit 3 is placed on the stage 2 The substrate 10 is moved, and three colors of ink are ejected toward a specific position, whereby a color filter of a specific pattern is formed on the substrate 10. Further, in the case where the coating is not performed for a long period of time, the coating unit 3 is disposed in the ink-preventing prevention device 4 disposed beside the stage 2 in order to prevent the ink of the coating unit 3 from drying.

Furthermore, in the following description, the direction in which the coating unit 3 is moved is set to the X-axis side. The direction orthogonal to the horizontal plane on the X-axis direction is referred to as the Y-axis direction, and the direction orthogonal to both the X-axis and the Y-axis direction is referred to as the Z-axis direction.

In the present embodiment, the coating unit 3 is formed by applying ink of three colors of RGB onto the substrate 10, and has a head unit 31 for ejecting ink and a holder 32 for supporting the head unit 31. The holder 32 has a support member 32a provided at both end portions of the stage 2 in the Y-axis direction, and a beam portion 32b that connects the two support members 32a, and has a substantially gate shape by the support member 32a and the beam portion 32b. Further, a rail 21 extending in the X-axis direction is provided at a position adjacent to the stage 2, and the support members 32a are slidably provided on the rails 21, respectively. Further, the supporting member 32a is provided with a driving device such as a linear motor, and by driving the linear motor, the supporting member 32a can be moved in the X-axis direction and stopped at an arbitrary position. That is, the coating unit 3 can be moved in the X-axis direction across the state on the stage 2, and stopped at an arbitrary position. Further, the rail 21 is extended until the ink drying device 4 is prevented, and the coating unit 3 can prevent the ink drying device 4 from being stopped by driving the linear motor.

Further, the beam unit 32b is provided with a head unit 31 for ejecting ink. The head unit 31 can be moved up and down with respect to the substrate 10 by the raising and lowering operation of the beam portion 32b with respect to the support member 32a. Thereby, when the application operation of ejecting the ink to the substrate 10 is performed, the distance between the substrate 10 and the head unit 31 is adjusted to be appropriate. Further, the head unit 31 has a size of about half of the dimension of the stage 2 in the Y-axis direction, and is attached to the beam portion 32b so as to be movable in the Y-axis direction. That is, the head unit 31 opposed to the substrate 10 at a specific position in the X-axis direction can be moved in the Y-axis direction to face the entire Y-axis direction region of the substrate 10 at a specific position in the X-axis direction. Further, the head unit 31 may be formed to have a size sufficiently larger than the dimension of the substrate 10 in the Y-axis direction.

Further, the head unit 31 is provided with a plurality of head modules 5, and ink is ejected from the head module 5. That is, the head module 5 is formed by integrating a plurality of coating heads 51, and a plurality of head modules 5 are arranged side by side at a predetermined interval. The coating head 51 is an ink ejecting apparatus that uses a piezoelectric element as a driving source, and has a nozzle surface 51a (see FIG. 3) in which a plurality of nozzles for ejecting ink are arranged. to In the present embodiment, a nozzle hole is formed in the nozzle surface 51a, and the nozzle front end substantially coincides with the nozzle surface 51a. Further, in the head module 5, the nozzle faces 51a of all the coating heads 51 that are integrated are disposed toward the substrate 10 side. Further, by driving the piezoelectric element, the ink can be ejected dropwise from the respective nozzles arranged on the nozzle surface 51a. Thereby, the discharge pattern can be formed by ejecting a specific ink to a specific position of the application region on the substrate 10. That is, while the holder 32 is moved in the X-axis direction (+ direction), ink is ejected from a nozzle located at a specific position on the substrate 10. Then, the head unit 31 is moved to the Y-axis direction end portion of the beam portion 32b while the holder 32 is stopped at the X-axis direction end portion of the substrate 10, and the holder 32 is moved in the X-axis direction (-direction). The ink is ejected from a nozzle located at a specific position on the substrate 10, whereby a specific pattern can be formed on the entire substrate 10.

Here, when the production operation of the substrate 10 is not stopped for a long period of time, such as the production of the color filter is temporarily stopped, the ink drying device 4 prevents the ink of the coating head 51 from drying.

The ink drying prevention device 4 prevents the ink in the nozzle (ink in contact with the atmosphere) from drying out by ejecting ink from the nozzle of the coating unit 3 and performing a rinsing operation. The ink drying prevention device 4 has a rinsing tray 42 that discards (flushes) ink.

The rinsing tray 42 is disposed on the base 41 in plural, and is disposed for each of the head modules 5. That is, when the rinsing tray 42 is stopped when the head unit 31 is stopped on the ink drying device 4, all the head modules 5 and the rinsing tray 42 are disposed to face each other.

Further, as shown in FIG. 4, the rinsing tray 42 has a box shape that is open on the side of the head module 5, and is formed to cover the entire size of the head module 5 in a state of being opposed to the head module 5. and. The rinsing tray 42 has a solvent storage portion 44 for storing ink or a solvent constituting the ink (referred to as a solvent or the like), and stores a certain amount of a solvent or the like at the bottom. The solvent storage unit 44 is provided to supply a solvent or the like to the porous member 46 to be described later, and the solvent or the like of the solvent storage unit 44 is not used up by supplying a solvent or the like from an external supply device (not shown).

In the rinsing tray 42, a porous member 46 is disposed substantially at the center. Porous texture The member 46 is used to form a solvent atmosphere with the head module 5. The porous member 46 is disposed in the solvent storage portion 44 of the rinse tray 42 and forms a solvent atmosphere on the porous member 46 by absorbing the solvent of the solvent reservoir 44, thereby preventing the ink in the nozzle from drying.

The porous member 46 is a sponge-like substance, and in the present embodiment, TECHNOPOROUS (registered trademark) is used. In addition, the porous member 46 may be other than TECHNOPOROUS, and may be a solvent that absorbs the solvent or the like of the solvent storage unit 44 and forms a solvent atmosphere. For example, if it has a continuous bubble structure like TECHNOPOROUS (registered trademark), the absorbed solvent or the like easily moves in the porous member 46 by continuous bubbles, even if the evaporation of the solvent or the like progresses with time, due to the absorbed solvent. Since it moves to the nozzle opposing surface 46a, it is easy to form a solvent atmosphere continuously on the nozzle opposing surface 46a.

The porous member 46 is formed in a rectangular parallelepiped shape and has a nozzle opposing surface 46a opposed to the nozzle of the head module 5. The nozzle facing surface 46a is formed in a flat shape and is formed to be substantially parallel to the nozzle surface 51a. By forming this flat shape, a uniform solvent atmosphere can be formed on the nozzle opposing surface 46a. In other words, when the solvent or the like of the solvent storage unit 44 is absorbed by the porous member 46, the solvent or the like moves in the porous member 46 and is substantially uniformly dispersed in the porous member 46. Further, when the solvent or the like evaporates from the surface of the porous member 46 with time, since the nozzle opposing surface 46a is formed flat, the solvent or the like evaporates throughout the entire nozzle opposing surface 46a, and is parallel to the nozzle opposing surface 46a. A uniform solvent atmosphere is formed in the area. Further, a solvent atmosphere having a high solvent concentration (a solvent atmosphere having a high solvent vapor pressure) is formed near the nozzle opposing surface 46a, and a solvent atmosphere having a small solvent concentration (solvent) is formed as it goes away from the nozzle opposing surface 46a. A solvent atmosphere with a low vapor pressure). A solvent atmosphere SB (specific solvent atmosphere) capable of preventing solvent vapor pressure (appropriate solvent vapor pressure) in which the ink in the nozzle is dried is selected from the solvent atmosphere, and a nozzle is placed in the solvent atmosphere SB, thereby suppressing the nozzle The ink inside evaporates to prevent the ink from drying out.

In the present embodiment, the nozzle facing surface 46a and the nozzle front end (nozzle surface 51a) In the positional relationship, the front end of the nozzle is set at a position where the solvent atmosphere SB is disposed. Specifically, the height of the porous member may be set such that the nozzle front end (nozzle surface 51a) is disposed in the solvent atmosphere SB, or the nozzle front end (nozzle surface 51a) may be used by the lifting mechanism of the head unit 31. The adjustment is performed in a manner of being disposed in the solvent atmosphere SB. In either case, the height of the porous member 44 is set such that the nozzle front end (nozzle surface 51a) is disposed in the solvent atmosphere SB. Therefore, when the head unit 31 is stopped on the drying prevention device 4, the respective head modules 5 are stopped at positions facing the nozzle opposing faces 46a of the respective porous members 44, and all the nozzles are disposed on the porous member 44. The state of the solvent vapor pressure in the specific solvent atmosphere SB.

Further, even when the time elapses, the solvent or the like in the rinse tray 42 evaporates with the solvent or the like absorbed by the porous member 46, but the nozzle facing surface 46a of the porous member 46 and the nozzle surface 51a of the head module 5 are The positional relationship also remains unchanged. In other words, even if the solvent or the like in the porous member 46 evaporates, the solvent or the like in the rinse tray 42 is absorbed, and the absorbed solvent or the like moves to the nozzle opposing surface 46a, thereby always supplying the nozzle forming the solvent atmosphere. The solvent or the like in the vicinity of the facing surface 46a can suppress the change in the positional relationship between the nozzles of the head module 5 and the liquid surface of the solvent or the like with time. That is, by arranging the front end of the nozzle in the solvent atmosphere SB for a long time, it is possible to prevent the ink in the nozzle from drying.

As described above, according to the ink-preventing apparatus of the above-described embodiment, the porous member 46 containing the solvent of the ink is disposed in the rinse tray 42, and the nozzle is disposed in the solvent atmosphere formed on the nozzle opposing surface 46a of the porous member 46. SB, therefore, it is possible to prevent the ink in the nozzle from drying. That is, since the shape of the porous member 46 does not change over time, the distance between the nozzle opposing surface 46a of the porous member 46 and the front end of the nozzle is suppressed from changing with time. In other words, the solvent is absorbed in the porous member 46, and the distance between the solvent absorbed by the porous member 46 and the tip end of the nozzle can be maintained in a fixed relationship even when the time passes. Therefore, the solvent at the tip end portion of the nozzle when the nozzle tip is first disposed can be disposed. The atmosphere and the solvent atmosphere at the tip end portion of the nozzle after a certain period of time are suppressed to substantially the same solvent atmosphere SB. Therefore, with Since the change in the solvent atmosphere at the tip end of the nozzle can be suppressed as compared with the conventional ink-preventing device in which the liquid level changes with time, it is possible to suppress the drying of the ink in the nozzle (the ink in the nozzle which is in contact with the atmosphere). Further, since the nozzle tip end can be disposed in the solvent atmosphere SB to prevent the ink in the nozzle from drying, it is possible to suppress the amount of ink discarded during the flushing, and to suppress the ink from being consumed endlessly.

Further, in the above embodiment, the example in which the flushing tray 42 is provided for each of the head modules 5 has been described. However, the plurality of head modules 5 may be provided as one set, and the plurality of flushing trays 42 may be provided. It is also possible to provide one flush tray 42 for the entire head unit 31.

In the above embodiment, the nozzle opposing surface 46a is an example of the surface of the porous member 46. However, depending on the choice of the solvent or the like and the material of the porous member 46, it is formed on the porous member 46. Liquid film (solvent film). In this case, the surface formed by the solvent film may be set to the nozzle facing surface 46a.

5‧‧‧ head module

42‧‧‧ rinse tray

44‧‧‧Solvent storage department

46‧‧‧Porous components

46a‧‧‧Nozzle facing

51a‧‧・Nozzle surface

SB‧‧‧ solvent atmosphere

Claims (3)

An ink-preventing device for preventing ink drying of a coating head having a plurality of nozzles for ejecting ink, and comprising: a rinsing tray formed with a solvent storage portion for storing a solvent of the ink; and a porous a porous member having a solvent that is immersed in a solvent storage portion of the rinse tray and containing the ink; and the porous member has a nozzle facing surface opposite to the nozzle, and the height of the porous member is The method is as follows: in a state where the coating head is located on the rinsing tray, the front end of the nozzle is located in a specific solvent atmosphere formed between the opposite surface of the nozzle and the front end of the nozzle. An ink-preventing apparatus according to claim 1, wherein said nozzle facing surface is formed of a solvent film formed on said porous member. An ink-preventing preventing device according to claim 1 or 2, wherein said porous member has a continuous bubble configuration.