KR20130060848A - Apparatus of dispensing liquid crystal - Google Patents

Abstract

PURPOSE: A liquid crystal discharging device is provided to make a volume of liquid crystals loaded on a substrate uniform as the liquid crystals flowing into a body unit are free-heated by passing through a heating line. CONSTITUTION: A liquid crystal discharging device comprises a liquid crystal supply unit, a gantry, and a plurality of head members. The head members are joined to the gantry to be movable and discharges liquid crystals with an inkjet method. The head members includes: a body unit(600) with a liquid crystal storing space containing the liquid crystals; a cover unit(700) which closes the liquid crystal storing space by being joined to the body unit; and a nozzle which is connected to the body unit and discharges the liquid crystals to a substrate. The body includes a heating line for free-heating the liquid crystals supplied by the liquid crystal supply unit.

Description

Liquid crystal discharge device {APPARATUS OF DISPENSING LIQUID CRYSTAL}

The present invention relates to a liquid crystal ejection apparatus, and more particularly, to an apparatus for ejecting liquid crystal (Liquid Crystal) to the substrate by an inkjet method.

In recent years, liquid crystal displays have been widely used in display units of electronic devices such as mobile phones and portable computers. The liquid crystal display device comprises: a color filter substrate on which a black matrix, a color filter, a common electrode, and an alignment layer are formed; A liquid crystal layer is formed between the thin film transistor (TFT), the pixel electrode, and the array substrate on which the alignment layer is formed, thereby obtaining an image effect by using a difference in refractive index of light according to the anisotropy of the liquid crystal.

As a method of forming a liquid crystal layer between a color filter substrate and an array substrate, there is a liquid crystal injection method or a liquid crystal dropping method. The liquid crystal injection method is a method in which the color filter substrate and the array substrate are bonded to each other by a predetermined interval, and the liquid crystal is injected and filled into the space therebetween.

The liquid crystal dropping method is a method of dropping a liquid crystal in the display area defined by the seal line after forming the seal line in the seal line region on the color filter substrate or the array substrate. After the liquid crystal is loaded, the color filter substrate and the array substrate are aligned, and the liquid crystals are pressed to spread evenly on the entire surface, and the color filter substrate and the array substrate are bonded by curing the seal pattern through UV and heat treatment processes. .

On the other hand, Patent Document 1 describes a processing liquid discharge device having a liquid crystal tank receiving liquid crystal from a liquid crystal supply source and heads dropping liquid crystal onto a substrate in fluid communication with the liquid crystal tank. However, since the processing liquid discharge device described in Patent Document 1 has a structure in which fresh liquid supplied from the liquid crystal supply source flows directly into the liquid crystal tank, the liquid crystal dropped by causing a temperature deviation to the liquid crystal stored inside the liquid crystal tank when the fresh liquid flows into the liquid crystal tank. The volume is not uniform.

Patent Document 1: Korea Patent Publication 10-2011-0059120 (2011. 06. 20. published)

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal ejection apparatus which makes the volume of liquid crystal dropped onto a substrate uniform.

The objects of the present invention are not limited thereto, and other objects not mentioned may be clearly understood by those skilled in the art from the following description.

According to an aspect of the invention, the liquid crystal supply unit; Gantry; A plurality of head members movably coupled to the gantry and discharging a liquid crystal by an inkjet method, the head member comprising: a body part provided with a liquid crystal storage space for containing the liquid crystal; A cover part coupled to the body part to seal the liquid crystal storage space; And a nozzle in fluid communication with the body portion, the nozzle discharging the liquid crystal onto a substrate, wherein the body portion is provided with a heating line through which the liquid crystal supplied from the liquid crystal supply portion is pre-heated. An apparatus may be provided.

In addition, a hole is formed below the heating line, and the liquid crystal supplied through the liquid crystal supply part is pre-heated in the heating line, and then the liquid crystal discharged to the lower portion of the liquid crystal storage space. An apparatus may be provided.

In addition, the liquid crystal ejection apparatus may further include a head member moving unit configured to linearly move the head members disposed side by side in the longitudinal direction of the gantry along the longitudinal direction of the gantry.

In addition, the head member moving unit may be provided with a liquid crystal discharge device for linearly moving the head members along the longitudinal direction of the gantry independently of each other.

According to another aspect of the present invention, there is provided a substrate support unit comprising: a substrate support unit on which a substrate is placed and which is linearly movable in a first direction; A gantry provided above the movement path of the substrate supporting unit; A plurality of head members movably coupled to the gantry and discharging a liquid crystal by an inkjet method; A liquid crystal supply unit supplying liquid crystal to the head members, wherein the head member comprises: a body portion provided with a liquid crystal storage space for containing the liquid crystal; A cover part coupled to the body part to seal the liquid crystal storage space; And a nozzle in fluid communication with the body portion, the nozzle discharging the liquid crystal onto a substrate, wherein the body portion is provided with a heating line through which the liquid crystal supplied from the liquid crystal supply portion is pre-heated. An apparatus may be provided.

According to the exemplary embodiment of the present invention, the liquid crystal flowing into the body portion passes through the heating line and is pre-heated, thereby making it possible to make the volume of the liquid crystal dropped onto the substrate uniform.

In addition, according to the embodiment of the present invention, it is possible to make the temperature distribution of the liquid crystal stored in the body portion uniform.

1 is a view showing the configuration of an inkjet liquid crystal coating equipment.
FIG. 2 is a perspective view of the liquid crystal discharge part of FIG. 1.
3 is a plan view of the liquid crystal discharge part of FIG. 1.
4 is a view illustrating the first driving unit of FIG. 3.
5 is a view showing the side of the head member moving unit of FIGS. 2 and 3.
6 is a front view of the first mobile unit of FIG. 5.
7 is an exploded perspective view showing the reservoir tank of the head member of FIG.
FIG. 8 is a cross-sectional view taken along line AA ′ of the reservoir tank of FIG. 7.
FIG. 9 is a view illustrating a level change of a liquid crystal in a liquid crystal storage space when there is no protrusion partition in the reservoir tank of FIG. 7.
FIG. 10 is a view illustrating a level change of a liquid crystal in a liquid crystal storage space when there is a protrusion partition in the reservoir tank of FIG. 7.

Hereinafter, a liquid crystal discharge apparatus according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a view showing the configuration of an inkjet liquid crystal coating equipment.

The liquid crystal coating equipment 1 of FIG. 1 is a facility for applying liquid crystal to a substrate by an inkjet method of discharging droplets. The substrate may be a color filter (CF) substrate or a thin film transistor (TFT) substrate of the liquid crystal display panel, and the liquid crystal may be coated on the entire surface of the color filter (CF) substrate or the thin film transistor (TFT) substrate.

Referring to FIG. 1, the liquid crystal coating apparatus 1 may include a liquid crystal discharge unit 10, a substrate transfer unit 20, a loading unit 30, an unloading unit 40, a liquid crystal supply unit 50, and a main control unit 90. ). The liquid crystal discharge portion 10 and the substrate transfer portion 20 are arranged in a line in the first direction I and can be positioned adjacent to each other. A liquid crystal supply part 50 and a main control part 90 are disposed at positions facing the substrate transfer part 20 with the liquid crystal discharge part 10 as a center. The liquid crystal supply part 50 and the main control part 90 may be arranged in a line in the second direction II. The loading unit 30 and the unloading unit 40 are disposed at positions facing the liquid crystal discharge unit 10 with the substrate transfer unit 20 as a center. The loading section 30 and the unloading section 40 may be arranged in a line in the second direction II.

Here, the first direction I is an arrangement direction of the liquid crystal discharge portion 10 and the substrate transfer portion 20, the second direction II is a direction perpendicular to the first direction I on the horizontal plane, (III) is a direction perpendicular to the first direction (I) and the second direction (II).

The substrate to which the liquid crystal is to be applied is brought into the loading section 30. The substrate transferring unit 20 transfers the substrate loaded into the loading unit 30 to the liquid crystal discharging unit 10. The liquid crystal discharging portion 10 receives liquid crystal from the liquid crystal supplying portion 50 and discharges the liquid crystal onto the substrate by an ink jet method for discharging liquid droplets. When the liquid crystal discharge is completed, the substrate transfer section 20 transfers the substrate from the liquid crystal discharge section 10 to the unloading section 40. The substrate coated with the liquid crystal is taken out of the unloading portion 40. The main control unit 90 controls the overall operations of the liquid crystal discharge unit 10, the substrate transfer unit 20, the loading unit 30, the unloading unit 40, and the liquid crystal supply unit 50.

FIG. 2 is a perspective view of the liquid crystal discharge part of FIG. 1. 3 is a plan view of the liquid crystal discharge part of FIG. 1.

Referring to FIGS. 2 and 3, the liquid crystal discharge part 10 includes a base B, a substrate support unit 100, a gantry 200, a gantry moving unit 300, head members 400, and head member movement. The unit 500, the liquid crystal discharge amount measuring unit 800, the nozzle inspection unit 900, and the head member cleaning unit 1000 are included.

The base (B) may be provided in a rectangular parallelepiped shape having a constant thickness. The substrate support unit 100 is disposed on the upper surface of the base B. The substrate support unit 100 has a support plate 110 on which the substrate S is placed. The support plate 110 may be a rectangular plate. The rotation driving member 120 is connected to the lower surface of the support plate 110. The rotation drive member 120 may be a rotary motor. The rotation driving member 120 rotates the support plate 110 around a rotation center axis perpendicular to the support plate 100. [

When the support plate 110 is rotated by the rotation drive member 120, the substrate S can be rotated by the rotation of the support plate 110. [ When the long-side direction of the cell formed on the substrate to which the liquid crystal is to be applied faces the second direction II, the rotation driving member 120 can rotate the substrate such that the long-side direction of the cell is in the first direction I.

The support plate 110 and the rotation driving member 120 may be linearly moved in the first direction I by the linear driving member 130. The linear driving member 130 includes a slider 132 and a guide member 134. The rotation driving member 120 is provided on the upper surface of the slider 132. [ The guide member 134 is elongated in the first direction I in the center of the upper surface of the base B. A linear motor (not shown) may be incorporated in the slider 132 and the slider 132 is linearly moved in the first direction I along the guide member 134 by a linear motor (not shown).

The gantry 200 is provided at an upper portion of a path through which the support plate 110 is moved. The gantry 200 is spaced apart from the upper surface of the base B in the upward direction, and the gantry 200 is disposed so that the longitudinal direction thereof faces the second direction II. The head members 400 are coupled to the gantry 200 by the head member moving unit 500. The head members 400 may be linearly moved in the longitudinal direction of the gantry, that is, the second direction II by the head member moving unit 500, and may also be linearly moved in the third direction III.

The gantry moving unit 300 linearly moves the gantry 200 in the first direction (I). The gantry moving unit 300 includes a first driving unit 310 and a second driving unit 320. The first drive unit 310 is provided at one end of the gantry 200, and the second drive unit 320 is provided at the other end of the gantry 200.

4 is a view illustrating the first driving unit of FIG. 3.

Referring to FIG. 4, the first driving unit 310 linearly moves one end of the gantry 200 in the first direction I when the gantry 200 is linearly moved. The first drive unit 310 includes a first straight drive member 318. The connection member 312 is coupled to one bottom surface of the gantry 200, and the first linear driving member 318 is coupled to the bottom surface of the connection member 312. The first linear drive member 318 includes a guide rail 315 and a slider 317. The guide rail 315 has a longitudinal direction toward the first direction (I) and is disposed on one side edge portion of the upper surface of the base B with respect to the guide member 134 of the substrate support unit 100. The slider 317 is movably coupled to the guide rail 315. The connecting member 312 is coupled to the upper surface of the slider 317. The slider 317 may have a built-in linear motor (not shown). The slider 317 linearly moves in the first direction I along the guide rail 315 by the driving force of the linear motor (not shown). The second driving unit 320 has the same structure as the first driving unit 310.

Referring back to FIG. 2, the head members 400 discharge droplets of liquid crystal onto the substrate. A plurality of head members 400 may be provided. In the present embodiment, an example provided with three head members 410, 420, and 430 is provided, but is not limited thereto. The head members 400 may be arranged side by side in the second direction II and are coupled to the gantry 200. The head member 410 has a reservoir tank 411, a nozzle 413, and a bracket 415. The reservoir tank 411 contains liquid crystal supplied from the liquid crystal supply unit 50. The nozzle 413 is in fluid communication with the reservoir tank 411. The bracket 415 connects the reservoir tank 411 and the head member moving unit 500. The remaining head members 420 and 430 also have the same structure as the head member 410. The nozzle 413 is provided with a plurality of discharge holes (not shown) for discharging droplets of liquid crystal. For example, each nozzle may be provided with 128 or 256 discharge holes (not shown). The discharge holes (not shown) may be arranged in a row at intervals of a predetermined pitch. The discharge hole (not shown) may discharge the liquid crystal in an amount of μg.

The nozzle 413 may be provided with a piezoelectric element, and the droplet discharge amount of the discharge hole (not shown) may be independently controlled by controlling the voltage applied to the piezoelectric element.

The head member moving unit 500 may be provided to the individual head members 400, respectively. In the present embodiment, since three head members 410, 420, and 430 are provided by way of example, three head member moving units 500 may also be provided to correspond to the number of head members. Alternatively, one head member moving unit 500 may be provided, in which case the head members 400 may be integrally moved.

5 is a side view of the head member moving unit of FIGS. 2 and 3, and FIG. 6 is a front view of the first moving unit of FIG. 5.

5 and 6, the head member moving unit 500 includes a first moving unit 520 and a second moving unit 540. The first moving unit 520 moves the individual head member 410 linearly in the longitudinal direction of the gantry, that is, the second direction II, and the second moving unit 540 moves the individual head member 410 in the third direction. It moves linearly to (III).

The first moving unit 520 includes guide rails 522a and 522b, sliders 524a and 524b, and a moving plate 526. The guide rails 522a and 522b extend in the second direction II and may be spaced apart in the third direction III on the front surface of the gantry 200. Sliders 524a and 524b are movably coupled to the guide rails 522a and 524b, and a linear driver, for example, a linear motor (not shown) may be built in the sliders 524a and 524b. The moving plate 526 is coupled to the sliders 524a and 524b. The upper region of the moving plate 526 is coupled to the slider 524a located above, and the lower region of the moving plate 526 is coupled to the slider 524b located below. As illustrated in FIG. 6, the moving plate 526 linearly moves in the second direction II along the guide rails 522a and 522b by a driving force of a linear motor (not shown). As such, as the head members 410, 420, 430 are individually moved along the second direction II, the distance between the head members 410, 420, 430 may be adjusted.

The second moving unit 540 includes a guide member 542, a slider 544, a detector 546, and a controller 548. The guide member 542 is coupled to the moving plate 526 of the first moving unit 520 and guides the linear movement of the slider 544 in the third direction (III). The slider 544 is coupled to the guide member 542 to be linearly movable, and the slider 544 may include a linear driver, for example, a linear motor (not shown). The head member 410 is coupled to the slider 544 and is moved in the third direction III by linear movement of the slider 544 in the third direction III.

The detector 546 may be installed in the gantry 200, and detects a gap between the head member 410 and the substrate S. Detector 546 may be a laser sensor. The controller 548 generates a control signal corresponding to the detection signal of the detector 546 and transmits a control signal to the linear motor included in the slider 544 to control the driving of the linear motor. If it is determined that the distance between the head member 410 and the substrate S is out of the predetermined reference value according to the detection result of the detector 546, the controller 548 controls the driving of the linear motor (not shown) to control the head member. The gap between 410 and the substrate S is adjusted.

7 is an exploded perspective view showing the reservoir tank of the head member of FIG. FIG. 8 is a cross-sectional view taken along line AA ′ of the reservoir tank of FIG. 7.

Referring to FIG. 7, the reservoir tank 411 has a body part 600, a cover part 700, and a heat supply part 1100. The liquid crystal storage space LS is formed in the body 411. The body part 600 is provided with a liquid crystal supply unit 610, a first sensing unit 630, a pressure regulating unit 650, and a second sensing unit 670.

The liquid crystal supply unit 610 has an inflow port 611 and a heating line 613. An inlet port 611 is provided on top of the body portion 411. The inlet port 611 is connected to the liquid crystal supply unit 50 and the liquid crystal supply line 51. A valve 53 is provided between the liquid crystal supply 50 and the inlet port 611. Heating line 613 is in communication with inlet port 611. The heating line 613 is located in the liquid crystal storage space LS. The hole 615 is formed under the heating line 613. The liquid crystal supplied from the liquid crystal supply unit 50 is supplied to the liquid crystal storage space LS through the inlet port 611 and the heating line 613 through the hole 615.

The first sensing unit 630 has a first sensing port 631 and a first sensor 633. The first sensing port 631 is provided above the body 411. The first sensing port 631 is disposed adjacent to the inflow port 611. The first sensor 633 is mounted to the first sensing port 631. For example, the first sensor 633 may be an ultrasonic sensor. The first sensor 633 measures the liquid level of the liquid crystal stored in the liquid crystal storage space LS.

The pressure regulating unit 650 is provided at the top of the body portion 600. The pressure regulating unit 650 is disposed adjacent to the first sensing port 631. The pressure regulating unit 650 is connected to the pressure regulating member 651 by a pneumatic line 653. A valve 655 is provided between the pressure regulating member 651 and the pressure regulating unit 650.

Referring to FIG. 8, the second sensing unit 670 has a first port 671, a second port 673, and a tube 675. The first port 671 is coupled to communicate with the liquid crystal storage space LS at the rear lower side of the body portion 411. The second port 673 is coupled to communicate with the outside at the rear upper side of the body portion 411. The tube 675 connects the first port 671 and the second port 673. The liquid crystal stored in the liquid crystal storage space LS and the liquid crystal in the tube 675 have the same height. Therefore, the operator can determine the amount of the liquid crystal stored in the liquid crystal storage space LS by checking the height of the liquid crystal in the tube 675.

The cover part 700 is coupled to the body part 600 to close the liquid crystal storage space LS. The cover part 700 has a body plate 710 and a protruding partition 730. The body plate 710 is provided in a plate shape. The protruding partition 730 is provided in plurality in the longitudinal direction of the body plate 710 spaced apart. When the cover portion 700 is coupled to the body portion 600, the protruding partition 730 partitions the liquid crystal storage space LS. A sealing member 750 is provided around the protruding partition 730. The sealing member 750 prevents leakage of the liquid crystal stored in the liquid crystal storage space LS between the cover portion 700 and the body portion 600. By forming the protruding partition 730 on the body plate 710, the shaking of the liquid crystal surface may be minimized when the liquid crystal level in the liquid crystal storage space LS is measured by the sensing units 630 and 670. That is, referring to FIG. 9, if there is no protruding partition 730 that partitions the liquid crystal storage space LS, the surface height difference h1 of the liquid crystal generated due to the movement of the head member 410 is large. The level of the liquid crystal measured by the fields 630 and 670 is incorrect. On the contrary, referring to FIG. 10, when the protruding partition 730 partitioning the liquid crystal storage space LS is provided, since the height difference h2 of the liquid crystal generated by the movement of the head member 410 is small, sensing The liquid crystal level measured by the units 630 and 670 is accurate.

The heat supply part 1100 is provided on the side of the cover part 700. For example, the heat supply unit 1100 may be a heater. Heat generated in the heat supply unit 1100 is transferred to the body unit 600 through the cover unit 700 and heats the liquid crystal in the liquid crystal storage space LS. On the other hand, the heat of the body 600 is also transferred to the liquid crystal in the heating line 613. Therefore, the liquid crystal supplied from the liquid crystal supply unit 50 is heated in the heating line 613 and then sent to the liquid crystal storage space LS through the hole 615. Accordingly, since the liquid crystal pre-heated in the heating line 613 is supplied to the liquid crystal storage space LS, the temperature distribution of the liquid crystal in the liquid crystal storage space LS is maintained even when additional liquid crystal is introduced. Can be. In addition, since the hole 615 is present at the bottom of the heating line 613, the pre-heated liquid crystal flowing into the liquid crystal storage space LS through the hole 615 may be in the liquid crystal storage space LS due to the specific gravity difference. Are mixed evenly in the.

Referring back to FIG. 2, the liquid crystal discharge amount measuring unit 800 measures liquid crystal discharge amounts of the individual head members 410, 420, and 430. The liquid crystal discharge amount measuring unit 800 measures the amount of liquid crystal discharged from all the nozzles 413 for each of the head members 410, 420, and 430. By measuring the liquid crystal discharge amount of the individual head members 410, 420, 430, it is possible to check macroscopically whether or not the nozzles 413 of the individual head members 410, 420, 430 are abnormal. That is, when the liquid crystal discharge amount of the individual head members 410, 420, 430 deviates from the reference value, it can be seen that at least one of the nozzles 413 is abnormal.

The liquid crystal discharge amount measuring unit 800 may be disposed on one side of the substrate support unit 100 on the base B. The liquid crystal discharge amount measuring unit 800 may have first to third liquid crystal discharge amount measuring units 800a, 800b, and 800c. The first liquid crystal discharge amount measuring unit 800a measures the liquid crystal discharge amount of the head member 410, the second liquid crystal discharge amount measuring unit 800b measures the liquid crystal discharge amount of the head member 420, and the third liquid crystal discharge amount measuring unit 800c measures the liquid crystal discharge amount of the head member 430. Alternatively, one liquid crystal discharge amount measuring unit 800 may be provided. In this case, the liquid crystal discharge amount measuring unit 800 may sequentially measure the liquid crystal discharge amounts of the individual head members 410, 420, and 430. The head members 410, 420, 430 are moved in the first direction (I) and the second direction (II) by the gantry moving unit 300 and the head member moving unit 500 to be positioned above the liquid crystal discharge amount measuring unit 800. can do. The head member moving unit 500 may move the head members 410, 420, 430 in the third direction III to adjust the vertical distance between the head members 410, 420, 430 and the liquid crystal discharge amount measuring unit 800.

The nozzle inspection unit 900 checks the abnormality of the individual nozzles 413 provided to the head members 410, 420, and 430 through optical inspection. When it is determined that there is an abnormality in the macroscopic nozzles 413 by the liquid crystal discharge amount measurement unit 800, and it is determined that there is an abnormality in the unspecified nozzles 413, the nozzle inspection unit 900 may identify an abnormality of individual nozzles. You can proceed with a full inspection of the nozzle while checking. The nozzle inspection unit 900 may be disposed on one side of the substrate support unit 100 on the base B. The head members 410, 420, 430 are moved in the first direction (I) and the second direction (II) by the gantry moving unit 300 and the head member moving unit 500 to be positioned above the nozzle inspection unit 900. Can be. The head member moving unit 500 may move the head members 410, 420, 430 in the third direction III to adjust the vertical distance between the head members 410, 420, 430 and the nozzle inspection unit 900.

The head member cleaning unit 1000 performs a purging process and a suction process. The purging process is a process of spraying a part of the liquid crystal contained in the head members 410, 420, and 430 at high pressure. The suction process is a process of sucking and removing the liquid crystal remaining on the nozzle surfaces of the head members 410, 420, and 430 after the purging process.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

** Explanation of symbols on the main parts of the drawing **
B: base 100: substrate support unit
200: gantry 300: gantry moving unit
400: head member 500: head member moving unit
600: body 700: cover
800: liquid crystal discharge quantity measurement unit 900: nozzle inspection unit
1000: head cleaning unit 1100: heat supply unit

Claims (2)

A liquid crystal supply unit;
Gantry;
A plurality of head members movably coupled to the gantry and discharging a liquid crystal in an inkjet method,
The head member,
A body portion provided with a liquid crystal storage space for containing the liquid crystal;
A cover part coupled to the body part to seal the liquid crystal storage space;
And a nozzle in fluid communication with the body, for discharging the liquid crystal onto a substrate,
And a heating line in the body portion, in which the liquid crystal supplied from the liquid crystal supply portion is pre-heated. The method of claim 1,
A hole is formed in the lower portion of the heating line, and the liquid crystal supplied through the liquid crystal supply part is pre-heated in the heating line and then supplied to the lower portion of the liquid crystal storage space.

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