Automatic bonding system for liquid crystal display device and automatic bonding method using the same
09835883 · 2017-12-05
Assignee
Inventors
- Wan Woo Jung (Daegu, KR)
- Seung Lyul Lee (Paju-si, KR)
- Chun Il Kim (Goyang-si, KR)
- Chang Yeol Park (Paju-si, KR)
- Seung kil Lee (Goyang-si, KR)
Cpc classification
Y10T156/1744
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B32B39/00
PERFORMING OPERATIONS; TRANSPORTING
International classification
B32B37/00
PERFORMING OPERATIONS; TRANSPORTING
B32B37/10
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Disclosed is an automatic bonding system for an LCD device. The automatic bonding system includes a bonding unit configured to perform a process of bonding a first substrate to a second substrate, a first substrate supply unit configured to include an inverting arm and supply the first substrate to the bonding unit, a second substrate supply unit configured to include an adhesive resin coating unit and supply the second substrate to the bonding unit, a pre-hardening unit configured to perform a process of pre-hardening an adhesive resin that adheres the first and second substrates, and a hardening unit configured to perform a process of hardening the adhesive resin that adheres the first and second substrates. A gap between the first and second substrates bonded to each other by the bonding unit is a bonding gap controlled by a gap variable control stage.
Claims
1. An automatic bonding system for a liquid crystal display (LCD) device, the automatic bonding system comprising: a bonding unit configured to perform a process of bonding a first substrate to a second substrate; a first substrate supply unit configured to comprise an inverting arm, and supply the first substrate to the bonding unit; a second substrate supply unit configured to comprise an adhesive resin coating unit, and supply the second substrate to the bonding unit; a pre-hardening unit configured to perform a process of pre-hardening an adhesive resin that adheres the first and second substrates; and a hardening unit configured to perform a process of hardening the adhesive resin that adheres the first and second substrates, wherein the bonding unit comprises a gap variable control stage and supporters, wherein the supporters are configured to be positioned at edges of a bottom surface of the first substrate and support the first substrate, wherein a gap between the first and second substrates bonded to each other by the bonding unit is a bonding gap controlled by the gap variable control stage, wherein the gap variable control stage comprises a roll and a gap block which enable respective heights thereof to be adjusted, wherein the roll is configured to be positioned at an edge of a top surface of the first substrate unit such that bonding of the first and second substrates is initiated at one side edge of the first substrate, and wherein the gap block is disposed at side edges of the second substrate and is raised or lowered so that the height of the gap block is set to a thickness of the adhesive resin coated on the second substrate before bonding is performed by the roll.
2. The automatic bonding system of claim 1, wherein the gap variable control stage adjusts the bonding gap according to a size of each of the first and second substrates.
3. The automatic bonding system of claim 1, wherein in the bonding unit, the adhesive resin is raised along the first substrate by using a surface tension between the first substrate and the adhesive resin coated on the second substrate, thereby bonding the first and second substrates.
4. The automatic bonding system of claim 1, wherein the bonding unit comprises a gap dispenser configured to, before the first substrate is bonded to the second substrate, previously coat the same adhesive resin as the adhesive resin on one side surface of the first substrate to reduce air bubbles formed at a bonding timing.
5. The automatic bonding system of claim 1, wherein the pre-hardening unit comprises an ultraviolet (UV) light emitting diode (LED) configured to directly irradiate UV onto side surfaces of the bonded first and second substrates to enhance a hardening rate of the adhesive resin.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:
(2)
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(5)
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DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
(11) Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
(12) The terms described in the specification should be understood as follows.
(13) As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “first” and “second” are for differentiating one element from the other element, and these elements should not be limited by these terms.
(14) It will be further understood that the terms “comprises”, “comprising,”, “has”, “having”, “includes” and/or “including”, when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
(15) The term “at least one” should be understood as including any and all combinations of one or more of the associated listed items. For example, the meaning of “at least one of a first item, a second item, and a third item” denotes the combination of all items proposed from two or more of the first item, the second item, and the third item as well as the first item, the second item, or the third item.
(16) The term “on” should be construed as including a case where one element is formed at a top of another element and moreover a case where a third element is disposed therebetween.
(17)
(18) As illustrated, the touch panel type LCD device 10 according to an embodiment of the present invention includes a liquid crystal panel 20 and a touch panel 30 disposed on the liquid crystal panel 20.
(19) To provide a detailed description, the liquid crystal panel 20 includes a first substrate 21 that is an array substrate, a second substrate (a color filter substrate) 22 that faces the first substrate 21 to be separated from the first substrate 21, and a liquid crystal layer 23 that is formed between the first and second substrates 21 and 22. Although not shown, a plurality of gate lines that are formed in parallel to be separated from each other by a certain interval and a plurality of data lines, which defines a plurality of pixel areas by intersecting the plurality of gate lines, are formed on the first substrate 21. A thin film transistor (TFT) is formed at an intersection point of a corresponding gate line and data line in each of the plurality of pixel areas, and a plurality of pixel electrodes connected to the TFT through a contact hole are formed in each pixel area.
(20) The TFT includes a gate electrode, a gate insulating layer, a semiconductor layer, a source electrode, and a drain electrode.
(21) The plurality of pixel electrodes are separated from each other in a bar type, and are formed in each pixel area. Also, a common line and the gate line are formed in parallel on the same layer, and a plurality of common electrodes are formed in each pixel area. The plurality of common electrodes are electrically connected to the common line, and are arranged alternately with the plurality of pixel electrodes to be separated from a pixel electrode adjacent thereto.
(22) As a modification example, one pixel electrode may be formed in each pixel electrode in a plate type. In this case, a portion of the one pixel electrode may overlap a corresponding gate line to form a storage capacitor.
(23) When a plurality of pixel electrodes and common electrodes are formed to be separated from each other in each pixel area, the first substrate 21 is formed to operate in an in-plane switching (IPS) mode. When only a plate type pixel electrode except a common electrode is formed in each pixel area, the first substrate 21 is formed to operate in one of a twisted nematic (TN) mode, an electrically controlled birefringence (ECB) mode, and a vertical alignment (VA). In the present embodiment, the first substrate 21 operating in the IPS mode will be described as an example.
(24) A black matrix, which has an opening corresponding to a pixel area, is formed on the second substrate 22 facing the first substrate 21. A color filter layer, including a plurality of red, green, and blue color filters which are sequentially arranged repeatedly in correspondence with a plurality of the openings, is formed on the second substrate 22.
(25) An overcoat layer is formed on the color filter layer.
(26) First and second polarizers 25a and 25b , which selectively transmit specific light, are adhered to respective outer surfaces of the first and second substrates 21 and 22.
(27) The touch panel 30 is disposed on the liquid crystal panel 20.
(28) Here, the touch panel 30 disposed on the liquid crystal panel 20 is a resistive digitizer, and includes a film type upper substrate 32 (see
(29) When one position of the upper substrate 32 (see
(30)
(31) For convenience of description, only the touch panel 30 is schematically illustrated without illustrating the liquid crystal panel (20 of
(32) As illustrated in
(33) However, as illustrated in
(34) That is, the touch sensor of the touch panel 30 includes a capacitor that includes the lower electrode 33, the upper electrode 35, and a gap therebetween. In this case, when the finger 37 touches the touch panel 30, the touch sensor detects a capacitance change caused by a fringe field change of the capacitor.
(35) The touch panel 30 may be implemented as a resistive type, an infrared type, or an ultrasound type, in addition to the capacitive type.
(36) Here, the touch panel 30 is bonded to the liquid crystal panel (20 of
(37) The liquid crystal panel (20 of
(38) Moreover, the optical adhesive resin 220 (see
(39) Here, an automatic bonding system 100 (see
(40)
(41) As illustrated in
(42) A first loader/unloader unit 201, which supply the liquid crystal panel 20 onto a first stage 210, is disposed at the liquid crystal panel supply unit 200. A second loader unit 301, which inverts the touch panel 30 and provides the inverted touch panel 30 onto a supporter of a bonding unit, is disposed at the touch panel supply unit 300.
(43) The adhesive unit 400 includes a bonding unit 402 (which bonds the liquid crystal panel 20 and the touch panel 30 which are respectively supplied from the liquid crystal panel supply unit 200 and the touch panel supply unit 300), a pre-hardening unit 403, a loader/unloader unit 401, a hardening unit 404, and an unloader unit 405 which are sequentially disposed on a second stage 410.
(44) Here, the touch panel supply unit 300 is provided in the in-line type until loading of the touch panel 30, cleaning, stripping of a protective film, and measuring of a thickness are performed for the touch panel 30, and the touch panel 30 is inverted and supplied to a supporter 412 (see
(45) Here, the cleaning, the stripping of the projective film, and the measuring of the thickness which are performed for the liquid crystal panel 20 and the touch panel 30 are known technology, and thus, their additional descriptions are not provided.
(46) The adhesive unit 400 is provided in the in-line type by using the second stage 410 and a third stage 420.
(47) To provide a more detailed description, the first loader/unloader 201 is a general element, and allows a plurality of the liquid crystal panels 20 to be sequentially supplied to the first stage 210. A second loader unit (an inverting arm) 301 is a general element, and allows a plurality of the touch panels 30 to be sequentially supplied to the supporter 412 of the bonding unit 402.
(48) That is, the liquid crystal panel 20 is provided onto the first stage 210 by a loading robot (not shown) of the first loader unit 210. Also, the touch panel 20 is provided onto the supporter (412 of
(49) Here, the first stage 210 is an element on which the liquid crystal panel 20 is disposed for coating of the adhesive resin, and the supporter (412 of
(50) A slit nozzle unit (230 of
(51) Here, the adhesive resin 220 is an optical adhesive resin having an photocurable characteristic which is hardened by ultraviolet (UV), and has a high light transmittance and elasticity.
(52) Moreover, the adhesive resin 220 is coated on an entire surface except a partial border of the liquid crystal panel 20 by using the adhesive resin coating unit 202, and does not overflow to outside the liquid crystal panel 20.
(53) Therefore, in a process of bonding the touch panel 30 to the liquid crystal panel 20, the bonding unit 402 of the adhesive unit 400 adjusts a height of each roll 432 (see
(54) Accordingly, a separate cleaning process of removing the adhesive resin 220 overflowing to the outside is not performed, thereby enhancing an efficiency of a process.
(55) When a model of the bonded liquid crystal panel 20 and touch panel 30 is changed and thus a thickness or a bonding gap is changed, the bonding unit 402 receives information about the changed thickness or bonding gap and previously adjusts a height of each of the roll 432 (see
(56) As illustrated in
(57) That is, the adhesive resin coating unit 202 includes the storage tank 240, which stores the adhesive resin 220 filled thereinto, and the spray head 250 that includes the nozzle (not shown) discharging the stored adhesive resin 220 to the outside. The spray head 250 is connected to the adhesive resin storage tank 240 and a supply pipe (not shown), and in more detail, the adhesive resin 220 is supplied to the nozzle (not shown) of the spray head 250 through the supply pipe (not shown) of the adhesive resin storage tank 240.
(58) In this case, in the split nozzle unit 230, the spray head 250 scan-moves in one direction to discharge the adhesive resin 220 onto an entire surface except a partial border of the liquid crystal panel 20, thereby forming an adhesive resin layer.
(59) That is, the spray head 250 is provided in an approximate bar type crossing an upper portion of the liquid crystal panel 20, and has a length corresponding to an edge of one side of the liquid crystal panel 20 on which the adhesive resin 220 is to be coated.
(60) Therefore, the spray head 250 of the slit nozzle unit 230 is moved at a certain speed from one side edge to the other side edge of the liquid crystal panel 20, and simultaneously, a certain pressure is applied to the adhesive resin storage tank 240. Accordingly, the adhesive resin 220 filled into the adhesive resin storage tank 240 is discharged through the nozzle (not shown), thereby forming the adhesive resin layer on the liquid crystal panel 20.
(61) As a result, the adhesive resin 220 is coated on an entire surface except a partial border of the liquid crystal panel 20, and thus, an adhesive resin non-charging section is not formed in an area with the adhesive resin 220 coated thereon. Accordingly, air bubbles are considerably reduced, and an efficiency of an adhesive resin coating process can be more enhanced.
(62) The slit nozzle unit 230 includes a control unit (not shown) that precisely controls an amount of coated adhesive resin 200. The control unit precisely controls an amount and a thickness of the adhesive resin 220 coated on the liquid crystal panel 20. In detail, the laser displacement sensor measures a height of the coated adhesive resin 220 in real time, and the control unit receives the measured coating height to calculate an amount of coating. Also, the control unit transfers the coating thickness to the bonding unit 402, and allows the bonding unit 402 to adjust the roll (432 of
(63) As described above, the liquid crystal panel 20 with the adhesive resin 220 coated thereon is unloaded and transferred to a buffer (not shown) by a robot (not shown) of the first loader/unloader unit 201, and then, the transferred liquid crystal panel 20 is again unloaded and transferred to the second stage 410 by a third loader/unloader unit 401 and a robot (not shown) of the adhesive unit 400. The second stage 410 with the liquid crystal panel 20 transferred thereto is transferred to under the supporter (412 of
(64) Therefore, the touch panel 30 and the liquid crystal panel 20 are aligned, and are bonded to each other with the adhesive resin 220 therebetween.
(65) A bonding method will be described below with reference to
(66) When the robot of the third loader/unloader (401 of
(67) Subsequently, the supporter 412 and the second stage 410 (on which the liquid crystal panel 20 and the touch panel 30 are loaded at the rightmost side in
(68) A subsequent bonding method will be described with reference to a side view of
(69) The gap dispenser (422 of
(70) As described above, the bonding unit 402 includes the roll 432 enabling a height to be adjusted and a gap variable control stage including the gap block 442 of the second stage, and a gap may be adjusted according to a thickness of the two substrates.
(71) The roll 432 is lowered by the determined bonding height, and bonding is started from one side surface of each of the liquid crystal panel 20 and the touch panel 30. Subsequently, a position of the lowered roll 432 is maintained in a fixed state, and the supporter 412, which supports the second stage 410 with the liquid crystal panel 20 disposed therein and the touch panel 30 so as to be inclined, moves to the pre-hardening unit 403 disposed at the left in
(72) A height of the gap block 442 and a lowering height of the roll 432 may not be set to be more thinned than a thickness of the adhesive resin 220 coated on the liquid crystal panel 20 when the touch panel 30 is bonded to the liquid crystal panel 20. Instead of a method that applies a pressure to the touch panel 30 such that the gap block 442 and the roll 432 are more thinned than a thickness of the coated adhesive resin 220, the height of the gap block 442 is set to the thickness of the adhesive resin 220 coated on the liquid crystal panel 20, and when bonding is performed by the roll 432, the bonding is performed by a surface tension in which the adhesive resin 220 coated on the liquid crystal panel 20 is raised along a bonding surface of the touch panel 30 pushed by the roll 432. Therefore, after the bonding is performed, the adhesive resin 220 does not overflow to outside the two bonded substrates.
(73) The second stage 410, on which the bonded touch panel 30 and liquid crystal panel 20 are disposed, is transferred to the pre-hardening unit 403 disposed at the left, and a process of pre-hardening the adhesive resin 220 charged between the touch panel 30 and the liquid crystal panel 20 is performed.
(74) Subsequently, a pre-hardening method will be described with reference to the perspective view of
(75) The pre-hardening unit 403 includes four bar type UV hardeners 413 that irradiate UV. Each of the UV hardeners 413 includes a plurality of UV light emitting diodes (LEDs) 423. When the second stage 410 with a bonding panel 40 disposed thereon is moved to a lower portion of a space between the four bar type UV hardeners 413, the UV hardeners 413 are lowered to be respectively disposed at four edges of the bonding panel 40, and allow UV to be irradiated from the UV LEDs 423.
(76) Therefore, a process of hardening the adhesive resin 220 charged into the bonding panel 40 is performed.
(77) According to the present invention, since the UV LEDs 423 are respectively disposed at four side surfaces of the bonding panel 40, the UV hardeners 413 of the pre-hardening unit 403 may directly irradiate UV on respective side surfaces, thus preventing UV from being scattered and irradiating a more amount of UV than the existing method. Accordingly, a hardening rate and an efficiency of a process can increase, and the process cost can be reduced.
(78) In detail, a mercury UV lamp or a metal halide lamp may irradiate UV, but has a service life of 1,400 to 2,000 hours which is shorter than that of the UV LED.
(79) Therefore, the mercury UV lamp or the metal halide lamp is frequently replaced. However, by using the UV LED having a service life longer than that of the lamps, the present invention can enhance an efficiency of a process, and reduce the process cost.
(80) Moreover, the UV LED releases lower heat and consumes lower power than the mercury UV lamp or the metal halide lamp, thus more enhancing an efficiency of a process.
(81) The bonding panel 40 pre-hardened on the second stage 410 is again unloaded and transferred to the third stage 420 of the hardening unit 404 by the third loader/unloader 401 of
(82) Subsequently, a hardening method will be described with reference to the perspective view of
(83) The hardening unit 404 includes four bar type UV hardeners 414 that irradiate UV. Each of the UV hardeners 414 includes a plurality of UV lamps 424.
(84) The third stage 420 of the hardening unit 404 is raised up to a height of each of the UV lamps (lamp type side UV lamps) 424 which are respectively disposed at four side surfaces of the bonding panel 40 which has been pre-hardened after bonding, and a lamp type top UV lamp 434 performs hardening along with the side UV lamps 424. When the hardening is ended, the touch panel type LCD device is finished, and the third stage 420 is lowered and unloaded by the unloader unit 405.
(85) As described above, the automatic bonding system 100 performs the process of bonding the liquid crystal panel 20 to the touch panel 30 with the optical adhesive resin 220, and thus, bonding work of the liquid crystal panel 20 and the touch panel 30 is automated. Accordingly, a productivity increases, a bonding state is uniform and stable, and a reliability of a product is enhanced.
(86) In addition to the process of bonding the touch panel 30 to the liquid crystal panel 20, according to the present invention, the automatic bonding system 100 may perform a process of bonding the touch panel 30 to a protective window (not shown) which performs a function of a window for protecting the LCD device from an external impact, or may perform a process of bonding the protective window to the liquid crystal panel 20.
(87) As described above, the automatic bonding system performs the process of bonding the liquid crystal panel to the touch panel with the optical adhesive resin, and thus, bonding work of the liquid crystal panel and the touch panel is automated. Accordingly, a productivity increases, a bonding state is uniform and stable, and a reliability of a product is enhanced. In particular, panels having various thicknesses are bonded to have various gaps by using the gap block and roll of the bonding unit that adjusts the gap between the touch panel and the liquid crystal panel, and by using the gap dispenser that coats the adhesive resin on one side surface of the touch panel, the touch panel is bonded to the liquid crystal panel in a state where formation of air bubbles is minimized by a contact between the adhesive resins when the bonding process starts to be performed, thus securing the optimal process condition. Also, the coated adhesive resin can be prevented from overflowing, and thus, a separate cleaning process of removing the adhesive resin overflowing to the outside is not performed, thereby more enhancing an efficiency of a process.
(88) Moreover, the adhesive resin coating unit scan-moves the adhesive resin to coat the adhesive resin at one time, thus more enhancing an efficiency of the adhesive resin coating process. Also, since a whole surface of the substrate is coated, an adhesive resin non-charging section is not formed, and thus, air bubbles are considerably reduced. In addition, an amount of coated adhesive resin can be precisely controlled, thus enhancing an efficiency of a process.
(89) Moreover, by pre-hardening the adhesive resin with the UV LED, a more amount of light is irradiated than a case of using the mercury UV lamp or the metal halide lamp, and thus, a hardening rate increase, thereby increasing an efficiency of a process.
(90) Moreover, a quality of an image can be prevented from being degraded, and an internal intensity against an external impact or pressure can be enhanced.
(91) It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.