CN111347792B

CN111347792B - Printing apparatus and printing method

Info

Publication number: CN111347792B
Application number: CN201911265526.1A
Authority: CN
Inventors: 金仁浩; 孙尚郁; 金大星; 丁宣旭
Original assignee: Semes Co Ltd
Current assignee: Semes Co Ltd
Priority date: 2018-12-21
Filing date: 2019-12-11
Publication date: 2021-11-02
Anticipated expiration: 2039-12-11
Also published as: CN111347792A; KR20200077889A

Abstract

The present invention relates to a printing apparatus and a printing method. The printing apparatus may include an inkjet head supplying a chemical solution onto a substrate, a first voltage supply unit, and a second voltage supply unit. The first voltage supply part may apply a first voltage with a first polarity to the liquid medicine until the liquid medicine is discharged from the inkjet head, and the liquid medicine may be charged with the first polarity. The second voltage supply unit may apply a second voltage having a second polarity to the chemical solution until the chemical solution reaches the substrate, and may control a discharge path of the chemical solution between the inkjet head and the substrate. According to the present invention, the chemical solution can be accurately supplied from the nozzle of the inkjet head to a desired portion of the substrate.

Description

Printing apparatus and printing method

The present application has priority to korean patent application No. 10-2018-.

Technical Field

Exemplary embodiments of the present invention relate to a printing apparatus and a printing method. More particularly, exemplary embodiments of the present invention relate to a printing apparatus including an inkjet head capable of supplying a chemical solution onto a substrate and a printing method performed using the printing apparatus.

Background

In order to manufacture a display device such as a liquid crystal display device or an organic light emitting display device, when an alignment film or a color filter is formed on a substrate, a printing device using an ink jet head that discharges a chemical solution onto the substrate is used. Preferably, the chemical solution supplied from the inkjet head is vertically discharged onto the substrate from a nozzle disposed on a discharge surface of the inkjet head.

However, in practice, the chemical solution is frequently discharged from the nozzles of the inkjet head onto the substrate at an arbitrary angle called a jetting angle (jetting angle), and thus the chemical solution cannot be accurately supplied onto a desired portion of the substrate.

Disclosure of Invention

Technical problem

The invention aims to provide a printing device which can accurately discharge liquid medicine from a nozzle of an ink jet head to a substrate.

Another object of the present invention is to provide a printing method using a printing apparatus capable of accurately discharging a chemical solution from a nozzle of an inkjet head onto a substrate.

Technical scheme

According to one aspect of the present invention, there is provided a printing apparatus including an inkjet head, a first voltage supply unit, and a second voltage supply unit. The ink jet head is capable of supplying a liquid chemical onto a substrate. The first voltage supply part may apply a first voltage with a first polarity to the liquid medicine until the liquid medicine is discharged from the inkjet head, and the liquid medicine may be charged with the first polarity. The second voltage supply unit may apply a second voltage having a second polarity to the chemical solution until the chemical solution reaches the substrate, and may control a discharge path of the chemical solution between the inkjet head and the substrate.

In an exemplary embodiment, the first voltage supply part may apply the first voltage to a periphery of a plurality of nozzles of the inkjet head, and the second voltage supply part may apply the second voltage to the chemical in a direction substantially perpendicular to a direction in which the chemical is discharged toward the substrate.

In some exemplary embodiments, a grounding part may be further included to ground the inkjet head and the substrate. For example, the grounding member may ground the discharge surface of the inkjet head and the back surface of the substrate.

In an exemplary embodiment, a medical fluid supply part supplying the medical fluid to the inkjet head may be further included. The liquid medicine supplied from the liquid medicine supply part to the inkjet head may not have polarity.

According to another aspect of the present invention, there is provided a printing method for supplying a liquid medicine from an inkjet head onto a substrate. The printing method may apply a first voltage having a first polarity to the chemical solution until the chemical solution is discharged from the inkjet head, may charge the chemical solution to the first polarity, may apply a second voltage having a second polarity to the chemical solution until the chemical solution reaches the substrate, and may control a discharge path of the chemical solution between the inkjet head and the substrate.

In an exemplary embodiment, the first voltage may be applied to a periphery of a plurality of nozzles of the inkjet head, and the second voltage may be applied to the chemical solution in a direction substantially perpendicular to a direction in which the chemical solution is discharged toward the substrate.

In some exemplary embodiments, the inkjet head and the substrate can be grounded. For example, the discharge surface of the inkjet head and the back surface of the substrate can be grounded.

In an exemplary embodiment, the liquid medicine can be supplied from a liquid medicine supply device to the inkjet head. The liquid medicine supplied to the ink-jet head may not have polarity.

Technical effects

According to an exemplary embodiment of the present invention, a voltage with a first polarity may be applied to the medical fluid such that the medical fluid is charged with the first polarity, and a second voltage with a second polarity may be applied to the medical fluid to control a discharge path of the medical fluid. Therefore, the chemical liquid can be discharged substantially perpendicularly to the substrate from the plurality of nozzles disposed on the discharge surface of the inkjet head. As a result, the chemical solution can be accurately supplied from the nozzles of the inkjet head to a desired portion of the substrate. However, the effects of the present invention are not limited to the above-described effects, and various expansions can be made without departing from the spirit and scope of the present invention.

Drawings

FIG. 1 is a schematic diagram of a printing apparatus used to illustrate an exemplary embodiment of the present invention;

fig. 2 is a flowchart for explaining a printing method of an exemplary embodiment of the present invention.

Detailed Description

Illustrative embodiments of the invention are described below. The present invention can be variously modified and variously modified, and the embodiments will be described in detail in this specification. However, the present invention is not intended to be limited to the specific forms disclosed, and all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention are to be understood. Like reference numerals are used for like components in describing the respective drawings. The terms first, second, etc. may be used to describe various components, but the components are not limited by the terms. The terms are used only to distinguish one constituent element from another constituent element. The terminology used in the description presented herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular references also include plural references without explicit recitation herein. The terms "comprises" or "comprising" or the like in the present application should be interpreted as referring to the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should not be interpreted as excluding the possibility of the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof in advance.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms defined in commonly used dictionaries should be interpreted as having meanings consistent with the meanings of the contexts of the related art, and should not be interpreted in an ideal or excessive formal sense unless explicitly defined in the present application.

Exemplary embodiments of the present invention are described below with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of a printing apparatus for explaining an exemplary embodiment of the present invention.

Referring to fig. 1, a printing apparatus 100 of an exemplary embodiment may be used in a printing process of supplying a chemical solution onto a substrate 10 to form a desired thin film or pattern on the substrate 10. For example, the printing apparatus 100 may be used in a printing process of supplying Ultraviolet (UV) ink onto the substrate 10 to form an alignment film or a color filter of a display device on the substrate 10.

In an exemplary embodiment, the printing apparatus 100 may include an inkjet head 11, a first voltage supply unit 17, and a second voltage supply unit 19.

The inkjet head 11 may supply a desired chemical solution onto the substrate 10 in the printing process. In an exemplary embodiment, the printing apparatus 100 may include a plurality of inkjet heads 11 that can be provided in one package. For example, 3 inkjet heads 11 in the printing apparatus 100 may be provided in one package.

The inkjet head 11 may include a plurality of nozzles 13 capable of discharging the chemical solution toward the substrate 10. For example, the inkjet head 11 may include about 128 nozzles or about 256 nozzles. The plurality of nozzles 13 of the inkjet head 11 may be arranged at substantially regular intervals. In other words, the plurality of nozzles 13 may be arranged at predetermined intervals on the discharge surface 15 of the inkjet head 11.

As illustrated in fig. 1, the substrate 10 may be positioned below the inkjet head 11. For example, the discharge surface 15 of the inkjet head 11 may substantially face the substrate 10. In this case, the plurality of nozzles 13 of the inkjet head 11 may be aligned in a direction substantially perpendicular to the upper surface of the substrate 10. Therefore, the chemical solution can be discharged from the plurality of nozzles 13 of the inkjet head 11 to a desired portion of the substrate 10 in a direction substantially perpendicular to the upper surface of the substrate 10.

The plurality of nozzles 13 of each of the inkjet heads 11 may discharge the chemical solution onto the substrate 10 in units of substantially μ g. In an exemplary embodiment, the inkjet head 11 may include piezoelectric elements corresponding to the plurality of nozzles 13. In this case, the number of the piezoelectric elements may be the same as the number of the nozzles 13. The chemical liquid may be supplied onto the substrate 10 through the plurality of nozzles 13 by operating the piezoelectric elements. The amount of the liquid medicine discharged from each of the plurality of nozzles 13 may be independently adjusted by individually controlling the voltage applied to the piezoelectric elements of the inkjet head 11.

The inkjet head 11 may supply the chemical solution onto a desired portion of the substrate 10 through the plurality of nozzles 13 during a printing process performed on the substrate 10 by the printing apparatus 100. However, the chemical solution is often not discharged from the nozzle 13 to a desired portion of the substrate 10 in the printing process. To solve these problems, the printing apparatus 100 of the exemplary embodiment may include the first voltage supply part 17 and the second voltage supply part 19. Also, the printing apparatus 100 may include a chemical supplying part (not shown) that may include a reservoir tank in order to supply the chemical to the inkjet head 11.

In an exemplary embodiment, the first voltage supply part 17 may apply a first voltage with a first polarity to the medical fluid until the medical fluid supplied from the medical fluid supply part is discharged from the inkjet head 11. For example, the first voltage supply part 17 may apply the first voltage with the first polarity to the chemical liquid supplied from the chemical liquid supply part to the inkjet head 11 until the chemical liquid is discharged through the nozzles 13 of the inkjet head 11 onto a desired portion of the substrate 10.

The chemical may not be charged when stored in the chemical supplying apparatus and when supplied from the chemical supplying apparatus to the inkjet head 11. In other words, the chemical liquid stored in the storage tank of the chemical liquid supply device may not have polarity, and thus the chemical liquid supplied from the chemical liquid supply part to the inkjet head 11 may not have polarity.

According to an exemplary embodiment, the first voltage supply part 17 of the printing device 100 applies the first voltage with the first polarity to the chemical solution that is not charged before the chemical solution is discharged from the inkjet head 11 onto the substrate 10, so that the chemical solution discharged from the inkjet head 11 onto the substrate 10 can be charged with the first polarity. Therefore, the liquid medicine supplied from the inkjet head 11 onto the substrate 10 can be charged with the first polarity. In this case, the first voltage supply unit 17 may apply the first voltage having the first polarity to the periphery of the plurality of nozzles 13 arranged on the discharge surface 15 of the inkjet head 11. For example, the first voltage supply unit 17 may apply a first voltage having the first polarity to the periphery of the plurality of nozzles 13 for discharging the chemical solution onto the substrate 10, thereby forming an electric field around each of the plurality of nozzles 13. The medical liquid can be charged by an electric field generated by the first voltage applied from such a first voltage supply part 17, and thus the medical liquid can have the first polarity. In an exemplary embodiment, the first voltage may have a negative polarity. Alternatively, the first voltage may have a positive polarity.

In an exemplary embodiment, the second voltage supply part 19 of the printing apparatus 100 may apply the second voltage having the second polarity to the chemical solution having the first polarity in a direction substantially perpendicular to a direction in which the chemical solution is discharged from the plurality of nozzles 13 toward the substrate 10. Wherein the second polarity may be opposite to the first polarity. For example, the second voltage supply part 19 may apply a second voltage with the second polarity to the chemical solution so as to generate an electric field substantially surrounding a direction in which the chemical solution is discharged toward the substrate 10. According to an exemplary embodiment, the second voltage supply part 19 may apply a second voltage with the second polarity to the chemical in order to control a discharge path of the chemical between the inkjet head 11 and the substrate 10. In other words, while the chemical solution discharged from each of the plurality of nozzles 13 of the inkjet head 11 reaches the substrate 10, the second voltage having the second polarity may be applied from the second voltage supplying part 19 to the chemical solution having the first polarity. Therefore, the chemical liquid can be accurately discharged from the plurality of nozzles 13 of the inkjet head 11 to a desired portion of the substrate 10. In an exemplary embodiment, the second voltage may have a positive polarity. Alternatively, the second voltage may have a negative polarity.

More specifically, the second voltage supply part 19 applies the second voltage with the second polarity to the chemical solution with the first polarity discharged from the nozzle 13, so that the discharge path of the chemical solution can be controlled between the inkjet head 11 and the substrate 10, and thus the chemical solution can be accurately supplied onto a desired portion of the substrate 10. Here, the discharge path of the chemical between the inkjet head 11 and the substrate 10 can be adjusted to the right or left by the level of the second voltage applied from the second voltage supply part 19. For example, the level of the second voltage having the second polarity applied from the second voltage supply unit 19 may be increased or decreased, and the discharge path of the chemical liquid having the first polarity may be moved to the right or left side on the upper portion of the substrate 10 by adjusting the level of the second voltage.

As described above, the printing apparatus 100 may include the first voltage supplying part 17 and the second voltage supplying part 19, and thus may apply a first voltage with the first polarity to the chemical solution until the chemical solution is discharged from the inkjet head 11 to charge the chemical solution with the first polarity, and may apply a second voltage with the second polarity to the chemical solution until the chemical solution reaches the substrate 10 to control a discharge path of the chemical solution between the inkjet head 11 and the substrate 10. In other words, a second voltage having the second polarity can be applied to the liquid medicine having the first polarity during the liquid medicine is supplied from the inkjet head 11 onto the substrate 10, and thus an attractive or repulsive force caused by the second voltage can act on the liquid medicine. The magnitude of the attractive force or the repulsive force affecting the liquid medicine may be increased or decreased by adjusting the level of the second voltage applied from the second voltage supply part 19. Therefore, the discharge path of the chemical solution can be accurately controlled between the inkjet head 11 and the substrate 10. As a result, the chemical solution can be accurately supplied from the inkjet head 11 to a desired portion of the substrate 10.

When the first voltage is applied from the first voltage supply unit 17 to the chemical solution and the second voltage is applied from the second voltage supply unit 19 to the chemical solution, other electronic factors affecting the chemical solution can be excluded. For this, in some exemplary embodiments, the printing apparatus 100 may include a grounding part 21 capable of grounding the inkjet head 11 and the substrate 10. For example, the grounding member 21 can be grounded to the discharge surface 15 of the inkjet head 11, and can be grounded to the back surface of the substrate 10. In this way, while the chemical solution is supplied from the nozzles 15 of the inkjet head 11 onto the substrate 10, other electronic factors that can affect the chemical solution can be excluded, and thus, the chemical solution can be more accurately discharged from the nozzles 15 of the inkjet head 11 onto a desired portion of the substrate 10.

Hereinafter, a printing method according to an exemplary embodiment of the present invention will be described with reference to the drawings.

Referring to fig. 1 and 2, the chemical may be supplied to the inkjet head 11 from a chemical supply part including the reservoir tank. In this case, the chemical supplied from the chemical supply part to the inkjet head 11 may not have polarity. Thereafter, a first voltage with the first polarity may be applied to the chemical solution until the chemical solution is discharged from the inkjet head 11 (step S201). That is, the first voltage supply unit 17 may apply the first voltage having the first polarity to the chemical solution until the chemical solution is discharged from the nozzles 13 of the inkjet head 11. Here, the first voltage having the first polarity may be applied to the periphery of the nozzles 13 arranged at predetermined intervals on the discharge surface 15 of the inkjet head 11. Accordingly, the liquid medicine discharged from the nozzles 13 of the inkjet head 11 can be charged with the first polarity. In an exemplary embodiment, the first voltage can have a negative polarity. Optionally, the first voltage can have a positive polarity.

A second voltage with the second polarity may be applied to the chemical solution until the chemical solution reaches the substrate 10 (step S203). That is, the second voltage supplying part 19 can apply the second voltage with the second polarity to the chemical solution while the chemical solution is discharged from the inkjet head 11 onto the substrate 10. Therefore, the discharge path of the chemical solution can be controlled between the inkjet head 11 and the substrate 10 by applying an attractive force or a repulsive force to the chemical solution. The second voltage with the second polarity may be applied in a direction substantially perpendicular to a direction in which the chemical solution is discharged onto the substrate 10. In an exemplary embodiment, the second voltage can have a positive polarity. Optionally, the second voltage can have a negative polarity. The magnitude of the attractive force or the repulsive force affecting the discharge path of the liquid medicine can be increased or decreased by adjusting the level of the second voltage applied from the second voltage supply part 19. Therefore, the discharge path of the chemical solution can be accurately controlled between the inkjet head 11 and the substrate 10.

As described above, by applying the second voltage to the chemical liquid with the first polarity while the chemical liquid is discharged from the inkjet head 11 onto the substrate 10, the chemical liquid can be discharged substantially perpendicularly to the substrate 10 regardless of the ejection angle of the chemical liquid discharged from the inkjet head 11. Therefore, the chemical solution can be accurately supplied to a desired portion of the substrate 10.

The first voltage is applied to the chemical solution from the first voltage supply unit 17, and the ink jet head 11 and the substrate 10 can be grounded while the second voltage is applied to the chemical solution from the second voltage supply unit 19 (step S205). In this case, the discharge surface 15 of the ink jet head 11 and the back surface of the substrate 10 can be grounded. Therefore, other electronic factors that can affect the chemical solution during the chemical solution is supplied from the nozzles 15 of the inkjet head 11 onto the substrate 10 can be excluded, and thus the chemical solution can be more accurately discharged from the nozzles 15 of the inkjet head 11 onto a desired portion of the substrate 10.

The printing apparatus and the printing method of the exemplary embodiments of the present invention can be applied to a process for manufacturing a display device such as a liquid crystal display device, an organic light emitting display device, or the like. For example, the printing apparatus and the printing method can be advantageously applied to a process for coating UV ink on a substrate.

The exemplary embodiments of the present invention have been described above, but it should be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the appended claims.

Claims

1. A printing apparatus, comprising:

an ink jet head for supplying a chemical solution onto a substrate;

a first voltage supplying unit that applies a first voltage having a first polarity to the periphery of a plurality of nozzles arranged on a discharge surface of the inkjet head until the liquid chemical is discharged from the inkjet head, and charges the liquid chemical to have the first polarity by an electric field generated by the first voltage; and

a second voltage supplying unit that applies a second voltage having a second polarity to the chemical liquid in a direction perpendicular to a direction in which the chemical liquid is discharged toward the substrate until the chemical liquid reaches the substrate, to control a discharge path of the chemical liquid between the inkjet head and the substrate.

2. The printing device of claim 1, further comprising:

and a grounding member that grounds the inkjet head and the substrate.

3. A printing device according to claim 2, wherein:

the grounding member grounds the discharge surface of the ink jet head and the back surface of the substrate.

4. The printing device of claim 1, further comprising:

a chemical liquid supply part supplying the chemical liquid to the inkjet head,

wherein the chemical liquid supplied from the chemical liquid supply part to the inkjet head has no polarity.

5. A printing method for supplying a liquid chemical from an ink jet head onto a substrate, comprising:

applying a first voltage having a first polarity to the periphery of a plurality of nozzles arranged on a discharge surface of the inkjet head until the liquid chemical is discharged from the inkjet head, and charging the liquid chemical to have the first polarity by an electric field generated by the first voltage; and

and applying a second voltage having a second polarity to the chemical liquid in a direction perpendicular to a direction in which the chemical liquid is discharged toward the substrate until the chemical liquid reaches the substrate, to control a discharge path of the chemical liquid between the inkjet head and the substrate.

6. The printing method of claim 5, further comprising:

grounding the ink jet head and the substrate.

7. The printing method according to claim 6, wherein:

the discharge surface of the ink jet head and the back surface of the substrate are grounded.

8. The printing method of claim 5, further comprising:

a step of supplying the liquid medicine from a liquid medicine supply part to the ink jet head,

wherein the liquid medicine supplied to the ink jet head has no polarity.