KR100581855B1 - Ink chamber and system for supplying ink therewith - Google Patents

Abstract

The present invention provides a manufacturing apparatus for manufacturing an organic electroluminescent element by an ink jet manufacturing method, the pressure control such as the negative pressure control of the head portion and the maintenance of the meniscus shape is easy, and combines the purification function of the head portion and the bubble removal function in the ink. In order to provide an ink chamber and an ink supply system having excellent chemical resistance, ink is supplied and stored for this purpose, and the upper space of the stored ink is decompressed or pressurized using a separate pressure regulator to pressurize the head portion. A first space portion for controlling the first space portion and communicating with the first space portion, wherein a membrane is formed in which ink does not pass through and at least bubbles in the ink pass therethrough, and is provided upstream of the ink around the membrane. The ink storage unit and a downstream side of the ink, the membrane being decompressed by the pressure adjusting device. To provide ink chambers and the ink supply system having the same according to the bubble removal to remove the air bubbles pass through, characterized in that formed, including a second space having a discharge for discharging ink of the ink storage portion to the outside.

Description

Ink chamber and system for supplying ink therewith

1 is a block diagram of an ink supply system according to a preferred embodiment of the present invention.

2 is a view showing a process in which ink is injected from the nozzle tip of the head portion.

3 is a block diagram of an ink supply system according to another preferred embodiment of the present invention.

4 is an exploded perspective view of the ink chamber according to the preferred embodiment of the present invention.

5 is a sectional view of the ink chamber according to FIG. 4;

6 is a perspective view of the main body of the ink chamber according to FIG. 4;

7 is a partially enlarged cross-sectional view showing a second space portion of the ink chamber according to FIG. 4.

8 and 9 are side views each showing opposite surfaces of a main body and a rear head forming a second space portion of the ink chamber according to FIG. 4;

10 is a cross-sectional view showing the operation of the water level measuring device of the ink chamber according to FIG. 4;

<Brief description of symbols for the main parts of the drawings>

10: first chamber 20: second chamber

22,140 membrane 30: pressure regulator

40: head portion 60: solvent chamber

100: ink chamber 110: main body

111: first space portion 112: second space portion

120: front head 130: rear head

150: water level measuring device

The present invention relates to an ink supply apparatus of an ink jet printing apparatus, and more particularly, to an ink chamber and an ink supply system of an ink jet printing apparatus capable of printing an organic film of a full color organic electroluminescent element (OLED).

In general, organic light emitting diodes are self-luminous displays that electrically excite fluorescent organic compounds to emit light, and can be driven at low voltages and thinned. Have In addition, the organic light emitting display device is attracting attention as a next-generation display that can solve the disadvantages pointed out as a problem in the liquid crystal display device, such as wide viewing angle, fast response speed.

The organic EL device capable of realizing a full color display device may be classified into a low molecular organic EL device using a low molecular weight light emitting material and a polymer organic EL device using a polymer light emitting material according to the type of the OLED.

Among them, a polymer organic electroluminescent device generally has two electrodes, an anode and a cathode, facing each other on a substrate, and a hole transport layer (HTL) and an emission layer between the anode and the cathode. It has a structure provided with organic film layers, such as Layer). In this case, the polymer organic electroluminescent device forms the hole transport layer and the light emitting layer with a polymer organic material. The polymer organic electroluminescent device has a lower driving voltage and power consumption than a low molecular organic electroluminescent device, and is easier to implement a large-area full color display device.

On the other hand, a low molecular organic electroluminescent element forms a low molecular organic material on a substrate on which an electrode is formed by a vapor deposition method, and a high molecular organic electroluminescent element forms a high molecular organic material by spin coating or an inkjet printing method.

Among them, the inkjet printing method is a method of dissolving or dispersing a light emitting material made of a polymer into a solvent to make a polymer ink, and printing the polymer ink on a substrate through an inkjet printing head.

In such an inkjet printing method, it is important to maintain a liquid meniscus shape at the nozzle of the head in order to prevent the image from being damaged, and to control the sound pressure of the head precisely, it is cleaner and the printing accuracy is higher. Can print. In addition, in order to accurately print the ink at a predetermined position, no foreign matter or bubbles exist in the head portion, and the ink using the xylene-based solvent which is mainly used as a solvent of the polymer organic film of the organic electroluminescent device is It must be volatile and chemically resistant.

 On the other hand, in the inkjet printing method using the piezoelectric drive method using the piezoelectric element to eject the ink from the head of the conventional inkjet printing method, the ink supply device to the head portion is a method of supplying ink with the water level difference by atmospheric pressure, It is classified in such a manner as to supply ink by the control system.

Among them, the ink is supplied by using the water level difference due to atmospheric pressure. The ink is supplied by the height difference between the head and the ink chamber. The ink is simple in configuration, easy to replace, and inexpensive. Fine adjustment of the supply is difficult, it is difficult to remove bubbles, and there is a fear that the nozzle of the head portion is clogged.

On the other hand, the method of supplying the ink by the control system is to store the ink in a Teflon coated storage bag (bag) and then pressurize the storage bag to adjust the discharge amount of the ink, the pressurized structure is fine liquid supply, Pressure control and cleaning is difficult.

Another way of supplying ink by the control system is to apply pressure directly to the ink in the auxiliary ink chamber connected to the head, so that bubbles can be removed and the negative pressure of the head can be easily controlled. It is vulnerable to the xylene solvent mainly used for the organic light emitting material of the light emitting element, and does not have a function of purging the solvent.

The present invention is to solve the above problems, in the manufacturing apparatus for manufacturing an organic electroluminescent device by the inkjet manufacturing method, it is possible to facilitate the pressure adjustment, such as the sound pressure control of the head portion and the maintenance of the meniscus shape. It is an object of the present invention to provide an ink chamber and an ink supply system.

It is another object of the present invention to provide an ink chamber and an ink supply system having a purifying function of the head portion and a bubble removing function in the ink.

It is another object of the present invention to provide an ink chamber and an ink supply system excellent in chemical resistance.

In order to achieve the above object, the present invention is the ink is supplied and stored, the first space portion for adjusting the pressure of the front end of the head portion by reducing or pressing the upper space of the stored ink using a separate pressure regulator, and An ink reservoir provided in an upstream side of the ink with a membrane mounted therein, the membrane being in communication with the first space portion, through which ink does not pass but at least bubbles in the ink pass therethrough, and downstream of the ink; And a second space portion having a bubble removing portion for removing bubbles that have passed through the membrane at a reduced pressure by the pressure adjusting device, and a discharge portion for discharging the ink of the ink storage portion to the outside. Provide an ink chamber.

According to another feature of the present invention, a height measuring unit for communicating with the first space portion outside the first space portion to measure the upper and lower limits of the stored ink may be further provided.

According to another feature of the invention, at least the inner surface of the first space portion and the second space portion may be provided with a Teflon material.

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

1 is a configuration diagram of an ink supply system according to an exemplary embodiment of the present invention. Referring to the drawings, the ink supply system includes a first chamber 10 in which ink is supplied and stored, and the first chamber 10. And a second chamber 20 for supplying ink and supplying ink to the head part 40, and a pressure adjusting part 30 for adjusting pressure of the first and second chambers.

The ink supply system according to the present invention can be used in an ink jet printing apparatus capable of manufacturing a polymer organic electroluminescent element using a polymer organic material as an organic film, and the head portion 40 is a piezoelectric driving method. Spray ink.

At this time, the head portion 40 should be maintained so that the negative pressure (陰 壓) to control the injection amount of the ink. 2 (a) to 2 (c) show jetting of the ink 44 at the tip of the nozzle 42 of the head portion 40 step by step. First, as can be seen in FIG. A predetermined degree of sound pressure is maintained in the portion 40 so that the liquid shape of the ink 44 at the tip of the nozzle 42 has a meniscus shape. According to an exemplary embodiment of the present invention, in order to maintain the meniscus shape, the head part 40 and the first and second chambers 10 and 20 are positioned at the same height in FIG. 1. In order to walk the pressure of -0.6 to -1.6 Kpa using the pressure regulator 30.

When the pressure of the nozzle 42 is applied by driving the piezoelectric element while the negative pressure is maintained and the ink 44 liquid at the tip of the nozzle is maintained in the meniscus shape, as shown in FIGS. 2B and 2C. , The desired amount of ink droplets 46 can be ejected.

In the present invention, in order to maintain the negative pressure at the tip of the nozzle 42 of the head portion 40 as described above, instead of connecting the pressure regulator 30 directly to the head portion 40, the pressure in the first chamber 10 The control unit 30 was connected. That is, the applicable first pressure reducing line 31 is connected between the first chamber 10 and the pressure regulating unit 30, whereby the pressure regulating unit 30 stores the ink stored in the first chamber 10. By depressing the upper part of the head pressure of the nozzle of the head portion 40 connected thereto is adjusted. The first pressure reducing line 31 can be applied to any pneumatic circuit that can adjust the pressure to a minute degree.

On the other hand, the second chamber 20 communicated with the first chamber 10 has a membrane 22 mounted therein to remove bubbles in the ink. That is, as shown in FIG. 1, the membrane 22 is mounted in the second chamber 20, which has a pore size of about 0.2 μm and ink does not pass through. Only bubbles in the ink can pass through. As shown in FIG. 1, the membrane 22 is mounted in the second chamber 20, and the pressure control unit 30 and the opposite side of the membrane 22 in which the ink is not stored in the second chamber 20 are stored. When the pressure is reduced by connecting the second pressure reducing line 33, bubbles in the ink are discharged to the side not contacted with the ink of the membrane 22, so that the ink supplied to the head portion 40 is the ink in which the bubble is removed. Can be. In the present invention, any of the second pressure reducing lines 33 may be applied to any pneumatic circuit capable of adjusting a minute pressure.

On the other hand, the nozzle of the head portion 40 should be managed so as not to be contaminated with bubbles or other foreign matter remaining in the ink, the present invention can be further provided with a purification function for this purpose. That is, as shown in Figure 1, the first pressure line 32 is provided between the first chamber 10 and the pressure control unit 30, the pressure control through the first pressure line (32) When the part 30 exerts a predetermined pressure on the first chamber 10, ink is discharged from the first chamber 10 through the nozzle of the head part 40 through the second chamber 20 so that the head part ( It is possible to remove bubbles or other impurities remaining in the nozzle of 40). Purification through the first pressure line 32 is possible by a pressure of about 40Kpa.

The first pressure line 32 has a function of purifying the nozzle of the head portion 40 in addition to the function of purifying the nozzle of the head portion 40 as described above. In order to suppress it, a small amount of 0.36 to 36 ml / min is supplied.

In the ink supply system according to the preferred embodiment of the present invention as described above, each component is preferably configured to have a chemical resistance to xylene which is used as a solvent of a polymer for an organic electroluminescent device. That is, the valves, tubes, vacuum ejectors and vacuum traps constituting the pneumatic circuit of the first and second pressure reducing lines 31 and 33 and the first pressure line 32 may be chemically resistant to xylene solvent. It may be provided with a material, it may be formed on the inner surface of the first and second chambers 10, 20, Teflon coating.

The operation of the ink supply system configured as described above is as follows.

First, when ink is supplied to the first chamber 10 and then pressurized through the first pressure line 32, the ink flows into the second chamber 20. At this time, the pressure is reduced through the second pressure reducing line 33 so that the bubbles in the ink are discharged through the membrane 22. The ink from which the bubbles are removed is discharged from the second chamber 20 by the pressurization of the first pressure line 32 to reach the head portion 40, and the head portion 40 is filled with a predetermined amount. In this case, the ink is discharged out of the nozzle of the head portion 40 to remove impurities and bubbles at the tip of the nozzle, and the pressure is reduced through the first decompression line 31 so that the negative pressure at the tip of the nozzle of the head portion 40 is reduced. maintain.

On the other hand, the ink supply system as described above can be enhanced by using a separate three-way valve (3way-valve), as shown in FIG.

That is, the ink discharged from the second chamber 20 is introduced into the head portion 40 via the first valve 51 and the second valve 52, and the first and second valves 51 ( 52 may be provided as a three-way valve.

The first valve 51 receives ink from the second chamber 20 and supplies the ink to the second valve 52. A second second ink recovery line 12 is further added to the first valve 51. It is provided.

The second valve 52 receives ink from the first valve 51 to supply ink to the head 40, and a second solvent chamber 60 is connected to the second valve 52.

The second ink recovery line 12 allows the ink in the second chamber 20 to be recovered when the ink to be ejected is to be replaced, and the ink in the first chamber 10 is the first ink recovery line 11. ), And the ink in the second chamber 20 may be recovered through the second ink recovery line 12 via the first valve 51 by pressurization using the first pressure line 32.

The solvent chamber 60 is to purify the ink liquid in the head portion 40 with a separate cleaning liquid, and the solvent chamber 60 connects the pressure regulating portion 30 and the second pressure line 34. Is connected through the second valve 52 to supply the cleaning liquid to the head portion 40. In the present invention, the second pressure line 34 may be applied to any pneumatic circuit capable of finely adjusting the pressure.

In the ink supply system as described above, the movement of the head 40 and the movement of the first and second chambers 10 and 20 may be simultaneously performed, thereby making it easier to control the pressure.

1 and 3, the ink supply system according to the preferred embodiment of the present invention has a structure in which the first chamber 10 and the second chamber 20 are separated from each other. It may be provided.

4 and 5 illustrate the ink chamber 100 in which the first chamber 10 and the second chamber 20 are integrally provided.

Referring to the drawings, the ink chamber 100 may be provided as a coupling structure of the front head 120 and the rear head 130 around the main body 110.

As shown in FIGS. 4 and 5, the front head 120 is coupled to the front end of the main body 110 to form a first space 111, and the rear head 130 is the main body 110. It is coupled to the rear end of the second space portion 112 to form. The chemical resistance to the xylene solvent between the front head 120 and the main body 110 and the main body 110 and the rear head 130 forming the first and second spaces 111 and 112 as described above. O-rings 122 and 132 of Teflon or Kalrez material may be mounted.

The first space 111 is where ink supplied through the ink supply pipe 121 formed in the front head 120 is stored, and corresponds to the first chamber 10 in FIGS. 1 and 3. The second space portion 112 communicates with the first space portion 111 to remove bubbles in the ink, and corresponds to the second chamber 20 in FIGS. 1 and 3.

The main body 110 forms a first space 111 on one side of the partition 110a and a second space 112 on the other side. As shown in FIGS. 4 and 5, the first and second through holes 113 and 114 are formed on the side of the first space 111 so that the pressure line and the pressure reducing line can be connected to each other. A discharge tube 115 capable of discharging is further provided.

On the other hand, as shown in FIG. 6 on the side of the second space portion 112, a predetermined first groove 116 is formed along the surface thereof, and the first groove 116 is formed in a closed curve. Preferably, the central portion 118 of the first groove 116 has a structure that is further recessed from the surface 110b of the outer partition of the first groove 116. A third through hole 117 is formed in the first groove 116 so that ink can be supplied from the first space 111 located across the partition wall, and any portion of the first groove 116 is formed. As described later, the first communication unit 119 is provided to supply ink to the rear head 130 without passing through the membrane.

Meanwhile, as shown in FIG. 4, the rear head 130 coupled to the main body 110 to form the second space part 112 has a pattern corresponding to the pattern formed on the rear surface of the main body 110. That is, a closed curved second groove 133 is formed on the surface of the rear head 130 facing the main body 110, and the central portion 134 of the second groove 133 is more than the outer side surface thereof. It has a recessed structure. In addition, a portion of the second groove 133 is provided with a second communication portion 135 corresponding to the first communication portion 119 of the main body 110 to supply ink without passing through the membrane. In the second communication unit 135, discharge holes 136 through which ink can be discharged to the outside are formed. In addition, the center portion 134 of the second groove 133 of the rear head 130 is provided with a decompression hole 131 through which the second decompression line 33 can be connected, as shown in FIG. 1. .

The membrane 140 having a pore size of 0.2 μm so that only the bubbles can pass through the second space portion 112 formed by the main body 110 and the rear head 130 as described above. It can be mounted, the installation structure is shown in Figures 7-9.

First, as shown in FIG. 7, when the main body 110 and the rear head 130 are coupled, a second space portion 112 is formed therebetween. The second space portion 112 includes a first groove 116 and a second groove 133 provided on opposite surfaces of the main body 110 and the rear head 130, and these first and second grooves ( 116, 133 is provided by the central surface 118, 134, the second space portion 112 is provided with a membrane 140. Ink does not pass through the membrane 140, and ink flows from the first space 111 through the third through hole 117 to the second space 112, as shown in FIGS. 4 to 6. Therefore, the ink storage portion 112a in which ink is stored is formed in the main body 110 direction, that is, the upstream side of the ink, and the rear head 130 direction, that is, the downstream side of the ink, is formed around the membrane 140. Is provided with a bubble removing unit 112b from which bubbles are removed. In the bubble removing unit 112b, a pressure reducing hole 131 is formed in the central surface 134 of the second groove 133 of the rear head 130 to penetrate the outside. As can be seen from the second pressure reducing line 33 of the pressure regulator 30 is connected. Accordingly, when the pressure is reduced through the pressure reduction hole 131, bubbles are removed from the ink stored in the main body 110 in the direction of the main body 110, that is, the ink storage portion 112a located upstream of the ink 140.

The bubble-free ink must be discharged to the outside to be supplied to the head portion. For this purpose, the main body 110 and the rear head 130 communicate with the ink without passing through the membrane 140. Parts 119 and 135 are provided.

That is, as shown in FIGS. 8 and 9, the membrane 140 is provided to cover the first groove 116 and the second groove 133 of the main body 110 and the rear head 130. The first and second communication portions 119 and 135 are provided to be out of the membrane 140. Therefore, the ink flows through these first and second communication portions 119 and 135 and is discharged to the outside by the discharge holes 136 formed in the second communication portions 135. The discharge hole 136 may of course be formed in another portion of the second groove 133 of the rear head 130.

Meanwhile, in the ink chamber as described above, the water level measuring device 150 is mounted on the main body 110 in order to measure the ink level of the first space 111. As shown in FIG. 4, the water level measuring device 150 includes a communication tube 151 communicating with the first space 111, and a measurement sensor provided at an upper portion and a lower portion of the communication tube 151. 152, 153 is provided. As the ink flows into the communication tube 151 and the ink flows into the first space 111, the measurement sensor is provided with an upper limit measurement sensor 152 and a lower limit measurement sensor 153, so that the ink liquid is insufficient. Do not As can be seen in FIG. 10, the measuring sensors scan a beam across the communication tube 151 and measure the water level through it.

In the ink chamber configured as described above, the opposing surfaces of the front head 120 and the main body 110 forming the first space 111 are made of a Teflon material having chemical resistance to xylene solvent, and the second space. It is preferable that the opposite surface of the main body 110 and the rear head 130 forming the portion 112 is also provided with a Teflon material. In addition, the inner surface of the communication tube 151 of the water level measuring device 150 is also provided with a Teflon material. Of course, the front head 120, the main body 110, and the rear head 130, which are members constituting the ink chamber, are formed of stainless steel and form the first and second space portions 111 and 112. Only Teflon coating can be applied.

Next, the operation of the ink chamber configured as described above will be described with reference to the accompanying drawings.

First, as shown in FIG. 4, the ink injected through the ink supply pipe 121 of the front head 120 flows into the first space 111 and is stored. Here, when pressure is applied from the pressure line connected through the first through hole 113, the ink flows into the second space 112 through the third through hole 117.

As shown in FIG. 7, the ink flowing into the second space part 112 remains in the ink storage part 112a between the membrane 140 and the main body 110, and at this time, the rear head 130. When the pressure is reduced from the decompression line connected through the decompression hole 131, the bubbles in the ink are discharged through the membrane 140 and the bubble removing unit 112b.

On the other hand, the ink of the ink reservoir 112a flows through the first communication unit 119 and the second communication unit 135 without passing through the membrane 140 by the pressure in the first space 111. It is discharged to the outside through the discharge hole 136 to flow into the head portion. Ink sufficiently filled up to the head portion is discharged a predetermined amount for purification.

After completing the purification function of the head portion, the pressure is reduced by the decompression line connected to the second through hole 114 of the main body 110 to maintain the sound pressure and the meniscus shape at the head of the nozzle head. Ink droplets are discharged by the action of the piezoelectric element.

The printing process is completed, and in order to remove the ink in the ink chamber, the ink is ejected through the discharge tube 115 formed in the first space 111.

According to the present invention as described above, the following effects can be obtained.

First, it is easy to control the sound pressure in the head portion and maintain the meniscus shape.

Second, it is easy to clean the head portion through the purification function, it is possible to remove the bubbles in the ink using the meniscus.

Third, it is excellent in chemical resistance of the ink supply system and the ink chamber, and can be applied to xylene solvent.                     

Fourth, it is easy to adjust the pressure of the ink.

Fifth, the ink chamber can be moved together with the head portion, so that it can be used without changing the pressure set value.

Sixth, the circuit for pressure regulation can be configured more simply.

Seventh, the inkjet method can be compatible with various heads.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Could be. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

Claims (3)

A first space part configured to control the pressure at the tip of the head by supplying and storing ink, and decompressing or pressing the upper space of the stored ink using a separate pressure controller; And An ink storage portion provided in communication with the first space portion, wherein a membrane is formed in which ink does not pass but at least bubbles in the ink pass, and is provided upstream of the ink with respect to the membrane; A second space portion provided on a downstream side and having a bubble removing portion for removing bubbles passing through the membrane at a reduced pressure by the pressure adjusting device, and a discharge portion for discharging the ink of the ink storage portion to the outside; And an height measuring unit communicating with the first space portion outside the first space portion to measure an upper limit and a lower limit of the stored ink. delete The method of claim 1, At least the inner surfaces of the first space portion and the second space portion is provided with a Teflon material.

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