KR101191283B1 - Surface acoustic wave ink-jet head - Google Patents

Abstract

According to an aspect of the present invention, there is provided an ionization chamber including an ink injection hole, a surface acoustic wave generating unit installed in the ionization chamber and generating surface acoustic waves to ionize ink injected into the ionization chamber, and one side of the ionization chamber to communicate with the ionization chamber. An injection head which is installed in and has an injection nozzle for injecting the ink particles therein to the ground direction. And an ink induction unit for guiding ink particles in the ionization chamber to the injection nozzle of the injection head, wherein the ink induction unit connects the first electrode mounted in the ionization chamber to the ionization chamber and the injection head. A moving passage made of a conductive material, a gas injection port formed in the ionization chamber to inject a gas for pushing ink particles in the ionization chamber to the injection head, a second electrode provided under the injection nozzle, and the second electrode. Disclosed is a surface acoustic wave inkjet head, comprising: an electrode applying unit configured to apply one of an anode and a cathode to one electrode and a movement path, and to apply the other of the anode and the cathode to the second electrode.

Description

Surface acoustic wave inkjet head {SURFACE ACOUSTIC WAVE INK-JET HEAD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface acoustic wave inkjet head for printing ink on a substrate by vaporizing the ink using surface acoustic waves and then spraying the ink.

In general, a display for displaying visual information is applied to a mobile phone, a mobile phone, a monitor, a digital TV, and the like. Recently, various technologies have been applied to the manufacturing process of a display in order to maintain such a display and maintain high quality.

An example of such techniques is surface acoustic wave inkjet technology. For example, an inkjet technique may be employed in the process of forming an alignment film (thin film for determining the direction of liquid crystal in a liquid crystal panel) on a glass substrate of a liquid crystal panel. When surface acoustic wave inkjet technology is used for formation of the alignment film of a liquid crystal display, the uniformity of a film thickness can be improved and the image quality of a liquid crystal panel can be improved.

In the case of the inkjet head used in the surface acoustic wave inkjet technology, the liquid ink is generally configured to be vaporized by the surface acoustic wave generator and then sprayed and deposited on the substrate. Since the vaporized ink is less dense than air, the ink is ejected from the bottom of the inkjet head upwards by the rising airflow generated thereby. That is, the ink of the inkjet head is ejected upward from the ground. Therefore, if various materials are to be stacked on the substrate or other production and processing processes must be performed continuously, the substrate must be turned over for the inkjet process. As such, the manner in which the ejection of the ink is carried out from the bottom of the inkjet head is unsuitable for such processes.

The present invention is to solve the above problems, the surface of the structure that can make the size of the ink particles by using the surface acoustic wave inkjet technology to make the size of the ink particles uniform and uniformize the printing thickness and also spray the vaporized ink toward the ground direction It is for providing an acoustic wave inkjet head.

In order to achieve the above object, the present invention provides an ionization chamber having an ink injection hole, a surface acoustic wave generator for generating surface acoustic waves so that the ink injected into the ionization chamber is ionized, and the ionization chamber; An injection head installed on one side of the ionization chamber so as to be in communication with the injection nozzle for injecting the ink particles therein in the ground direction, and an ink induction unit which guides the ink particles in the ionization chamber to the injection nozzle of the injection head. The ink induction unit may include a first electrode mounted in the ionization chamber, a moving passage made of a conductive material connecting the ionization chamber and the injection head, and ink particles formed in the ionization chamber to collect ink particles in the ionization chamber. A gas inlet through which gas for pushing up is injected, And a second electrode installed below the spray nozzle, and an electrode applying unit configured to apply one of an anode and a cathode to the first electrode and the movement path, and to apply the other of the anode and the cathode to the second electrode. Disclosed is a surface acoustic wave inkjet head characterized by.

The gas may be an inert gas containing nitrogen or helium.

The surface acoustic wave generator may be formed of a piezoelectric material which vibrates repeatedly at a predetermined frequency by an applied voltage.

The ink injection hole may be provided with an ink injection tube extending to the inside of the ionization chamber, and the surface acoustic wave generating unit may be installed below the ink injection tube.

The first electrode may be disposed above the surface acoustic wave generator, and the second electrode may be formed in a plate shape for supporting a target of the ink jet.

An inlet of the movement passage may be formed at an upper portion of the ionization chamber, and an outlet of the movement passage may be formed at an upper portion of the injection head.

A compressed air injection hole for injecting compressed air may be formed on the sidewall of the injection head, and the compressed air injection hole may have a shape inclined downward in the inward direction from the outside of the injection head.

According to the present invention having the above-described configuration, the ink particles can be refined and uniformized by vaporizing (ionizing) the ink using the surface acoustic wave generator.

In addition, the present invention can provide a structure capable of injecting the ionized ink in the ground direction through the structure of the ink induction unit having a first electrode, a moving passage, a gas injection port, a second electrode, and an electrode applying unit.

According to the present invention, the inert gas may be injected into the ionization chamber to stabilize the ionized ink, and the ionized ink may be easily introduced into the moving passage.

In addition, according to the present invention by injecting the compressed air into the injection head is configured to be compressed air is injected with the ink particles so that the ink particles can be smoothly injected.

1 is a cross-sectional view of a surface acoustic wave inkjet head according to an embodiment of the present invention.
2 is an operational state diagram of the surface acoustic wave inkjet head shown in FIG. 1;

EMBODIMENT OF THE INVENTION Hereinafter, the surface acoustic wave inkjet head which concerns on this invention is demonstrated in detail with reference to drawings.

1 is a cross-sectional view of a surface acoustic wave inkjet head according to an embodiment of the present invention.

Referring to FIG. 1, the surface acoustic wave inkjet head includes an ionization chamber 110, a surface acoustic wave generator 120, an injection head 130, and an ink induction unit.

The ionization chamber 110 provides a space for ionizing (vaporizing) the liquid ink. In the present invention, conductive ink is used as ink. The ionization chamber 110 may be formed of an insulating material such as a synthetic resin.

The ionization chamber 110 has an ink injection hole 111 for injecting liquid ink. The ink injection hole 111 is provided with an ink injection tube 112 extending from the outside to the inside of the ionization chamber 110. The ink injection pipe 112 is connected to the ink supply device through a tube or the like.

The surface acoustic wave generator 120 is installed in the ionization chamber 110 and generates a surface acoustic wave to ionize the ink injected into the ionization chamber 110. The surface acoustic wave generator 120 generates surface acoustic waves by vibrating by an electrical signal, and the liquid ink vibrates by surface acoustic waves and ionizes (vaporizes) to have a particle shape.

The surface acoustic wave generator 120 may be formed of piezoelectrics repeatedly vibrating at a predetermined frequency by a voltage applied thereto, and a typical example of such piezoelectric materials may be piezoelectric ceramics. The surface acoustic wave generator 120 operates at a frequency of 9 MHz or higher to ionize high viscosity ink of 10 cps or more into ink particles having a fine and uniform shape.

The surface acoustic wave generator 120 may be installed on an inner bottom surface of the ionization chamber 110, and may be installed below the ink injection tube 112 to apply surface acoustic waves to ink ejected from the ink injection tube 112. .

The injection head 130 is installed at one side of the ionization chamber 110 so as to communicate with the ionization chamber 110, and temporarily stores ink particles (ionized ink) in the ionization chamber 110 and sprays them to the outside. do. The jet head 130 has a jet nozzle 131 for jetting ink particles in the paper direction. The injection head 130 may be formed of an insulating material like the ionization chamber 110, and the injection nozzle 131 may be installed under the injection head 130.

The ink inducing unit functions to guide ink particles in the ionization chamber to the spray nozzle 131 of the spray head 130. The ink induction unit has a configuration including a first electrode 141, a moving passage 142, a gas injection hole 143, a second electrode 144, and an electrode applying unit 145.

The first electrode 141 is mounted in the ionization chamber 110, and functions to charge ink particles by a voltage applied from the electrode applying unit 145. The first electrode 141 may be installed above the surface acoustic wave generator 120 and may be supported on the inner wall of the ionization chamber 110.

The movement passage 142 connects the ionization chamber 110 and the injection head 130, and provides a space for the ink particles in the ionization chamber 110 to move to the injection head 130. Since the ionized ink particles have a property that the density of the ionized ink is lower than that of the atmosphere to move to the upper region of the ionization chamber 110, it is preferable to form an inlet of the movement passage 142 above the ionization chamber 110. The outlet of the movement passage 142 may be formed in the upper portion of the injection head 130, and specifically, may be formed in the cover 135 installed on the upper portion of the injection head 130.

The gas injection hole 143 is formed in the ionization chamber 110, and a gas for pushing ink particles in the ionization chamber 110 to the injection head 130 is injected into the gas injection hole 143. The gas injection hole 143 may be formed at an upper portion of the ionization chamber 110, and the gas injection hole 143 may be connected to the gas supply device through a tube or the like. As the gas injected into the gas inlet 143, an inert gas including nitrogen or helium may be used. These inert gases simultaneously perform the function of stabilizing the ink particles.

The second electrode 144 is installed below the spray nozzle 131, and provides attraction to the ink particles as a voltage is applied from the electrode applying unit 145. The second electrode 144 may be formed in a plate shape so as to support the ink ejection target (eg, the substrate 150).

The electrode applying unit 145 functions to apply one of an anode and a cathode to the first electrode 141 and the movement passage 142, and to apply the other of the anode and the cathode to the second electrode 144. The electrode applying unit 145 is electrically connected to the first electrode 141, the movement passage 142, and the second electrode 144 in the form of a power source.

According to the present exemplary embodiment, the electrode applying unit 145 is configured to apply an anode to the first electrode 141 and the movement passage 142 and to apply a cathode to the second electrode 144. However, a configuration in which a cathode is applied to the first electrode 141 and the movement passage 142 and an anode is applied to the second electrode 144 is also possible.

On the other hand, the compressed air inlet 146 for injecting the compressed air may be formed on the side wall of the injection head 130. This is to inject the compressed air into the injection head 130 so that the ink particles are smoothly injected. The compressed air inlet 146 may be connected to the compressed air supply device through a tube or the like.

The compressed air inlet 146 may have a shape inclined downward along the inward direction from the outside of the injection head 130. This is to direct the injection direction of the compressed air toward the injection nozzle (131).

Hereinafter, the operation of the surface acoustic wave inkjet head of the above-described configuration will be described with reference to FIG. 2.

FIG. 2 is an operating state diagram of the surface acoustic wave inkjet head shown in FIG. 1. In FIG. 2, the flow of ink is indicated by a solid arrow, and the flow of gas or compressed air is indicated by a dotted arrow.

As the ink supply device connected to the ink injection hole 111 is operated, ink liquid is injected into the ionization chamber 110. The injected ink liquid flows toward the surface acoustic wave generator 120 under the ink injection tube 112. Here, it is preferable to adjust the flow rate of the ink liquid so that the ink liquid of a predetermined flow rate falls on the surface acoustic wave generator 120. As the surface acoustic wave generator 120 generates the surface vibration wave, the ink liquid thereon is ionized.

Since the ionized ink particles are lower in density than the atmosphere, they move upward, and are charged to have a positive polarity by the first electrode 141 during the upward movement.

The inert gas injected from the gas injection hole 143 pushes the charged ink particles to move the ink particles through the movement passage 142. Since the movement passage 142 is charged with positive polarity by the electrode applying portion 145, the movement passage 142 provides repulsive force to the ink particles. The ink particles charged with the anode move toward the injection head 130 by the pressure provided by the inert gas and the repulsive force provided by the movement passage 142 charged with the anode.

The ink particles introduced into the spray head 130 are sprayed out of the spray nozzle 131 by the pressure of the compressed air flowing into the spray head 130, and the ink particles from the spray nozzle 131 are second electrodes 144. It is deposited on the substrate 150 on the). The second electrode 144 is charged to the cathode by the electrode applying unit 145 to provide attraction to the ink particles, and the ink particles are induced to deposit onto the substrate 150 by such attraction.

On the other hand, even without adopting a configuration for injecting compressed air into the injection head 130, it will be possible to induce the movement of the ink particles in the injection head 130 only by the attraction force provided by the second electrode 144.

In the above described with reference to the accompanying drawings, the surface acoustic wave inkjet head according to the present invention, the present invention is not limited by the embodiments and drawings disclosed herein, those skilled in the art within the scope of the technical idea of the present invention Various modifications can be made by this.

Claims (9)

An ionization chamber having an ink injection hole;
A surface acoustic wave generator configured to be installed in the ionization chamber and to generate surface acoustic waves to ionize the ink injected into the ionization chamber;
An injection head installed on one side of the ionization chamber so as to communicate with the ionization chamber, and having an injection nozzle for injecting ink particles thereinto the ground direction; And
An ink guiding unit for guiding ink particles in the ionization chamber to an ejection nozzle of the ejection head,
The ink induction unit,
A first electrode mounted in the ionization chamber;
A movement passage connecting the ionization chamber and the injection head, the inlet and the outlet being formed in an upper portion of the ionization chamber and an upper portion of the injection head, respectively;
A gas injection hole formed in the ionization chamber and into which a gas for pushing ink particles in the ionization chamber to the injection head is injected;
A second electrode disposed below the spray nozzle; And
And an electrode applying unit configured to apply one of an anode and a cathode to the first electrode and the movement passage, and to apply the other of the anode and the cathode to the second electrode. The method of claim 1,
The gas is surface acoustic wave inkjet head, characterized in that the inert gas containing nitrogen or helium. The method of claim 1,
The surface acoustic wave generator is formed of a piezoelectric material which is repeatedly vibrated at a predetermined frequency by an applied voltage. The method of claim 1,
The ink injection hole is provided with an ink injection tube extending to the inside of the ionization chamber,
The surface acoustic wave generating unit is a surface acoustic wave inkjet head, characterized in that provided below the ink injection pipe. The method of claim 1,
The surface acoustic wave inkjet head of claim 1, wherein the first electrode is disposed above the surface acoustic wave generator. The method of claim 1,
The second electrode is a surface acoustic wave inkjet head, characterized in that formed in the form of a plate for supporting the ejection target of the ink. delete The method of claim 1,
Surface acoustic wave inkjet head, characterized in that the compressed air inlet for injecting compressed air is formed on the side wall of the jet head. 9. The method of claim 8,
The compressed air injection hole is a surface acoustic wave inkjet head characterized in that it has a form inclined downward in the inward direction from the outside of the injection head.

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