KR101171154B1 - Recycling method of display panel - Google Patents

Abstract

The present invention relates to a recycling method of a display panel and a display device using the same. The recycling method divides the display panel into two or more panel portions by cutting the display panel along a predetermined cut surface, and divides the display panel into two or more panel portions. A panel cutting process of cutting the TFT array substrate larger than the color filter array substrate so that the lines are exposed to form stepped cut surfaces in each of the panel portions; A cut surface sealing process of bonding the TFT array substrate and the color filter array substrate with a sealant at a stepped cut surface of the panel portion; A bus line exposing step of exposing the bus lines by removing the thin films formed on the bus lines at a portion of the stepped cut surface not coated with the sealant; And a drive IC attaching process for attaching a drive IC or a flexible substrate to the bus lines exposed at the stepped cut surface.

Description

Recycling method of display panel {RECYCLING METHOD OF DISPLAY PANEL}

The present invention relates to a recycling method of a display panel used for a special purpose by cutting a liquid crystal module manufactured to a standard size to non-standard or other standard size and shape.

Various flat panel displays (FPDs) are being developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include liquid crystal displays (hereinafter referred to as "LCDs"), field emission displays (FEDs), plasma display panels (PDPs), and electroluminescence devices (electroluminescence devices). ). The flat panel display device is divided into a PM (Passive Matrix) display device and an AM (Active Matrix) display device according to its driving method. The electroluminescent device is divided into an inorganic electroluminescent device and an organic light emitting diode device (OLED) according to the material of the light emitting layer.

In the TFT TFT LCD, a thin film transistor (TFT) is formed as a switching element for each pixel. AM TFT LCD can be miniaturized compared to Cathode Ray Tube (CRT), which is applied to display in portable information equipment, office equipment, computer, etc., and is also rapidly replacing cathode ray tube in TV.

The liquid crystal module is bonded by a sealant and includes a liquid crystal panel including a TFT array substrate and a color filter array substrate, a backlight unit disposed below the liquid crystal panel, and various frames and cover members for assembling the liquid crystal panel and the backlight unit into one module. (Not shown). In the manufacturing process of the liquid crystal module, the manufacturing process of the AM TFT LCD includes substrate cleaning, substrate patterning process, alignment film forming / rubbing process, substrate bonding process, liquid crystal injection (or liquid crystal dropping) process, mounting process, inspection process, repair Process, module assembly process, and the like. Generally, liquid crystal module makers mass produce liquid crystal modules having the size and shape of standard specifications and deliver them to set makers.

In recent years, demand for display devices having sizes and shapes of non-standard specifications has been generated in various fields. In order to meet these demands, some LCD module remanufacturing makers purchase some defective liquid crystal modules such as A1, B, and C grade among standard standard liquid crystal modules shipped as finished products by liquid crystal module makers, and select the desired size of the liquid crystal module. After cutting in the form of and re-seal the cut surface to produce non-standard liquid crystal module. However, in the liquid crystal module reprocessing process, the portion without the drive IC (Integrated Circuit) is discarded due to the lack of the drive IC. Some of the liquid crystal panels discarded in the liquid crystal module reprocessing process are industrial wastes, causing waste of resources and adversely affecting the environment.

The present invention provides a method of cutting a display panel bonded with a sealant and recycling the display panel implemented as a part of the cut panel.

In the present invention, a recycling method of a display panel includes a TFT array substrate having source bus lines supplied with a data signal, bus lines intersecting the source bus lines and gate bus lines supplied with scan pulses, and A method of recycling a display panel including a color filter array bonded to the TFT array substrate with a first sealant and facing a TFT array substrate, wherein a color filter is formed, wherein the display panel is cut by cutting the display panel along a predetermined cut surface. A panel cutting process of dividing the above-described panel portion and cutting the TFT array substrate larger than the color filter array substrate so that the bus lines are exposed at a portion of the display panel to form stepped cut surfaces in each of the panel portions; A cut surface sealing process of joining the TFT array substrate and the color filter array substrate with a second sealant at a stepped cut surface of the panel portion; A bus line exposing step of exposing the bus lines by removing the thin films formed on the bus lines at a portion of the stepped cut surface not coated with the second sealant; And a drive IC attaching process for attaching a drive IC or a flexible substrate to the bus lines exposed at the stepped cut surface.

In the display device of the present invention, the drive IC is attached to the panel portion divided through the cutting process, the cut surface sealing process, the bus line exposure process, and the drive IC attaching process.

The present invention can recycle a panel portion which has been previously discarded by using a method of dividing the display panel and attaching the drive IC to the stepped cut surface of the divided panel portion. As a result, the present invention can minimize the waste of resources generated in the reprocessing process of the display panel, and furthermore, it is possible to open new types of applications by applying the present invention.

1 is an exploded perspective view showing a part of an LCD panel.
2 is a plan view showing a portion of a TFT array substrate.
FIG. 3 is a cross-sectional view showing a cross section of the TFT array substrate taken along the line "I '" in FIG.
4 is a flowchart illustrating a process step of a recycling method of a display device according to an exemplary embodiment of the present invention.
5 is a plan view illustrating an example of a cutting line in the panel cutting process S1.
FIG. 6 is a plan view showing the stepped cut plane in the panel portions P2-P4 under the line “AA” in FIG. 5.
FIG. 7 is a cross-sectional view showing a portion of the panel cut along the line "II-II '" in FIG.
8 is a cross-sectional view showing a cut surface to which the sealant is applied after the cut surface sealing process S2.
9 is a plan view showing the first embodiment of the drive IC attaching process S4.
10 is a plan view showing a second embodiment of the drive IC attaching process S4.

The display device of the present invention includes a display panel fabricated in a size and a shape of a nonstandard or another standard standard by reprocessing a standard standard display panel. Although an embodiment will be described below with reference to the LCD, it should be noted that the display device of the present invention is not limited to the LCD but can also be implemented as a panel in which a TFT array substrate and a color filter array are bonded, for example, an OLED panel. . The present invention cuts a part of an LCD panel or an OLED panel to which a TFT array substrate and a color filter array substrate are bonded, and seals a cut surface of a portion without a drive IC (a part of the panel that is conventionally discarded) with a separate sealant, and then cuts the cut surface. After exposing the bus lines, a separate drive IC is attached to the exposed surfaces of the bus lines, or a drive IC is attached through a flexible circuit board.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. In the following description, when it is determined that a detailed description of known functions or configurations related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Component names used in the following description are selected in consideration of ease of specification, and may be different from the actual product.

1 to 3 are views showing the structure of the LCD panel.

1 to 3, the LCD panel includes a TFT array substrate TFTA, a color filter array substrate CFA, and a liquid crystal layer LC formed between the substrates.

The TFT array substrate TFTA includes bus lines DL and GL, TFTs, a pixel electrode PXL, a storage capacitor Cst connected to the pixel electrode PXL, and the like formed on the lower glass substrate GLSL. . Bus lines include source bus lines and gate bus lines intersecting the source bus lines. The liquid crystal cells are driven by the voltage difference between the pixel electrode charging the data voltage through the TFT and the common electrode to which the common voltage is applied, thereby adjusting the transmission amount of light to display an image of the video data.

The color filter array substrate CFA includes a black matrix BM, a color filter CF (R), CF (G), CF (B)) and an overcoat layer (OCL) formed on the upper glass substrate GLSU. The overcoat layer OCL is a transparent resin layer covering the black matrix BM and the color filters CF (R), CF (G), and CF (B). The color filter array substrate CFA is in contact with the liquid crystal layer LC. Planarizes the inner surface.

An alignment film for setting the pre-tilt angle of the liquid crystal is formed on the inner surface of the TFT array substrate TFTA and the inner surface of the color filter array substrate CFA, which are in contact with the liquid crystal layer LC. The common electrode is formed on the color filter array substrate (CFA) in a vertical electric field driving method such as twisted nematic (TN) mode and vertical alignment (VA) mode, and is characterized by an in plane switching (IPS) mode and a fringe field switching (FFS) mode. In the same horizontal electric field driving method, the TFT array substrate TFTA is formed together with the pixel electrode PXL. A polarizing plate is attached to each of the outer surface of the TFT array substrate and the outer surface of the color filter array substrate.

Looking at the cross-sectional structure of the TFT array substrate TFTA, a gate metal pattern is formed on the lower glass substrate GLSL. The gate metal pattern is patterned with a metal such as aluminum-based or copper. The gate metal pattern includes a gate electrode GE of the TFT, a gate bus line GL connected to the gate electrode GE of the TFT, and a lower electrode of the gate pad GP formed at the end of the gate bus line GL.

The gate insulating layer GI is formed on the lower glass substrate to cover the gate metal pattern by including an insulating material such as silicon oxide (SiOx) or silicon nitride (SiNx). On the gate insulating layer GI, an active layer ACT and an ohmic contact layer OHM made of a semiconductor material such as amorphous silicon or polysilicon are formed, and a source-drain metal pattern is formed thereon. The source-drain metal pattern is patterned with metals such as molybdenum (Mo), titanium, tantalum, and molybdenum alloys (Mo alloy). The source-drain metal pattern includes the source electrode SE of the TFT, the source bus line connected to the source electrode SE of the TFT, the drain electrode DE of the TFT electrically connected to the pixel electrode PIX, and the end of the source bus line. And a lower electrode of the formed data pad DP.

The passivation layer PASSI is an inorganic insulating material such as a gate insulating film GI, an organic insulating material such as an acryl-based organic compound having a low dielectric constant, BCB, or PFCB, and covers the source drain metal pattern. Is formed. The passivation layer PASSI may include a first contact hole exposing a part of the source electrode SE of the TFT, a second contact hole exposing the bottom electrode of the data pad GP, and a bottom electrode of the gate pad GP. 3 contact holes are formed.

The pixel electrode PXL, the upper electrode of the gate pad GP, and the upper electrode of the data pad DP include indium tin oxide (ITO), tin oxide (TO), and indium tin zinc oxide (Indium). It is patterned with a transparent conductive material such as Tin Zinc Oxide (IZO) and Indium Zinc Oxide (IZO). The pixel electrode PXL is in contact with the source electrode SE of the TFT through the first contact hole. The upper electrode of the data pad DP is in contact with the lower electrode of the gate pad GP through the second contact hole. The upper electrode of the gate pad GP is in contact with the lower electrode of the gate pad GP through the third contact hole.

The output terminal of the source drive IC SIC shown in FIG. 5 is connected to the data pad GP through an anisotropic conductive film (ACF). The source drive IC (SIC) converts the digital video data into a gamma compensation voltage to generate a data voltage, and supplies the data voltage to the source bus lines DL through the data pad DP. Output terminals of the gate drive IC GIC shown in FIG. 5 are connected to the gate pad GP through the ACF. The gate drive IC GIC sequentially supplies a gate pulse (or scan pulse) to the gate bus lines GL through the gate pad GP.

4 is a flowchart illustrating a process step of a recycling method of a display device according to an exemplary embodiment of the present invention. The process description of FIG. 4 will be described with reference to FIGS. 5 to 8.

4 to 8, a recycling method of a display device according to an exemplary embodiment of the present invention may include a panel cutting process S1, a cut surface sealing process S2, a bus line exposing process S3, and a drive IC attaching process S4. ), And a module reassembly process (S5).

The panel cutting process S1 is a process of cutting an LCD panel in which a TFT array substrate and a color filter array substrate are bonded with a laser or a diamond cutter. For example, the LCD panel may be cut along line "A-A '" and / or line "B-B'" in FIG. Here, the TFT array substrate TFTA is cut larger than the color filter array substrate CFA in the cutting process so that the signal lines DL and GL are exposed as shown in FIGS. 6 to 8.

Conventional liquid crystal module reprocessing process is the first panel portion (P1) attached to both the source drive IC (SIC) and gate drive IC (GIC) of the separated panel portion in the cutting process (S1) for the LCD panel of FIG. Only the second to fourth panel portions P2 to P4 to which the source drive IC (SIC) and / or the gate drive IC (GIC) are not attached are discarded. In contrast, the present invention provides an output terminal of the drive ICs (SIC, GIC) in the process of attaching the drive IC, which will be described later, for the panel portions without the source drive IC (SIC) and / or the gate drive IC (GIC) after the cutting process. To the bus lines in the panel section.

Subsequent to the panel cutting process S1, the cut surface sealing process S2 is applied to the second sealant SEAL2 near the corners where the upper glass substrate GLSU and the lower glass substrate GLSL are in contact with each other in a stepped cut surface as shown in FIG. 7. The second sealant SEAL2 is irradiated with ultraviolet rays UV to cure the sealant SEAL2. Here, the second sealant SEAL2 is formed near the edge except for the portion where the bus lines are exposed on the stepped cut surface. The second sealant SEAL2 seals the gap between the TFT array substrate and the color filter array substrate at the cutting surface so that the liquid crystal does not leak at the cutting surface.

On the other hand, the module maker applies and hardens the first sealant SEAL1 on the opposite surface of the upper glass substrate GLSU and the lower glass substrate GLSL in the substrate bonding process. Therefore, the first sealant SEAL1 is used when the TFT array substrate and the color filter array substrate are first bonded to each other, and the second sealant SEAL2 forms the TFT array substrate and the color filter array substrate bonded with the first sealant SEAL1. It is used after the cutting process (S1) of the rework process for the included LCD panel.

Following the cut surface sealing process S2, the bus line exposing process S3 may include an insulating layer covered on the bus lines DL and GL to expose the source bus lines DL and the gate bus lines GL. The protective film, the alignment film, etc. are removed. In order to expose the source bus lines DL, the bus line exposing step S3 is a CMP used in a semiconductor process by aligning an alignment film made of polyimide (PI) covered on the source bus lines DL at a cut plane. (Chemical Mechanical Polishing) process to remove the thin film, or to remove the alignment layer etching solution including an alkali solution such as alcohol (alcohol) / potassium hydroxide (KOH) or a mixture thereof, and the protective film (PASSI) containing hydrofluoric acid or a mixture thereof Remove with protective etch. In order to expose the gate bus lines GL, the bus line exposing process S3 may remove the alignment layer and the passivation layer PASSI in the same manner as described above, and then may remove the source bus lines formed on the gate bus lines GL at the cut surface. DL) is removed using an etchant such as sulfuric acid or hydrochloric acid or nitric acid, or a source-drain metal etchant including a mixture thereof, and then the gate insulating layer GI and the semiconductor patterns ACT and OHM are replaced with hydrofluoric acid or a mixture thereof. Removed with the insulating film and semiconductor etching solution included. Meanwhile, the cut surface sealing process S2 may collectively remove thin films formed on the source bus lines DL and the gate bus lines GL by using the mixed solution of the above-described etching liquids. In addition, the cut surface sealing process S2 may be performed by applying the CMP process and the etching process using the etching solution to the thin films formed on the source bus lines DL and the gate bus lines GL using the above-described mixture of etching solutions. You can also remove it.

The drive IC attaching process S4 attaches the drive ICs SIC and GIC to the bus lines DL and GL exposed by the bus line exposing process S3 in the same manner as in FIG. 9 or 10. Taking the LCD panel shown in FIG. 5 separated by the cutting process S1 as an example, the drive IC attaching process S4 uses the ACF to expose the gate bus lines GL exposed to the cut surface of the second panel portion P2. Gate drive ICs (GIC). In the case of the third panel portion P3, the drive IC attaching process S4 uses the ACF to source drive ICs SIC on the source bus lines SL exposed to the cut surface of the third panel portion P3. Attach. In the case of the third panel portion P3, the drive IC attaching process S4 uses the ACF to source drive ICs SIC on the source bus lines SL exposed to the cut surface of the third panel portion P3. Attach. In the case of the fourth panel portion P4, the drive IC attaching process S4 uses the ACF to source drive ICs SIC on the source bus lines SL exposed to the cut surface of the fourth panel portion P2. Also, the gate drive ICs GIC are attached to the gate bus lines GL exposed on the cut surface of the fourth panel portion P4.

The module reassembly process S5 aligns the backlight unit under the panel portions P2 to P4 to which the drive ICs SIC and GIC are attached by the drive IC attaching process S4, and the panel portions P2 and P4. ) And backlight unit into one module. On the other hand, in the case of an OLED panel or a reflective LCD panel, a backlight unit is not required, so the module reassembly process (S5) is omitted when reprocessing the OLED panel or the reflective LCD panel.

9 is a plan view showing the first embodiment of the drive IC attaching process S4.

Referring to FIG. 9, the drive IC attaching process S4 directly attaches the drive ICs SIC and GIC to the bus lines DL and GL exposed by the bus line exposing process S3 using the ACF. . For this purpose, the pitch between the output terminals formed in the drive ICs SIC and GIC should be equal to the pitch P1 of the bus lines DL and GL exposed at the cut surface of the panel.

On the other hand, since the conventional drive ICs SIC and GIC are attached to the pads GP and DP arranged at a pitch narrower than the pitch between the bus lines, the pitch between the output terminals is between the pads GP and DP. It is set equal to the pitch. Therefore, when the drive ICs SIC and GIC are to be directly attached to the bus lines DL and GL exposed to the cut planes as illustrated in FIG. 9, the output terminal pitches of the drive ICs SIC and GIC are determined by the bus lines. It is necessary to redesign the drive ICs (SIC, GIC) because they must be equal to the pitch of (DL, GL).

10 is a plan view showing a second embodiment of the drive IC attaching process S4.

Referring to FIG. 9, the drive IC attaching process S4 adheres the output terminals of the flexible substrate FPC to the bus lines DL and GL exposed by the bus line exposing process S3 using an ACF. The drive ICs SIC and GIC are attached to the input terminals of the flexible printed circuit board FPC using the ACF. The flexible printed circuit board (FPC) may be selected from FPC (Flexible Printed Circuit), FW (Flexible Wire), FC (Flexible Circuitry) and the like.

The output terminal pitch of the flexible printed circuit board FPC should be equal to the pitch P1 of the bus lines DL and GL exposed at the cut surface of the panel. The input terminal terminal pitch of the flexible circuit board FPC should be equal to the output terminal pitch P2 of the conventional drive ICs SIC and GIC. Thus, in the case of the embodiment as shown in FIG. 10, the drive ICs do not need to be redesigned since they can be used as existing drive ICs.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. For example, the LCD panel described in the above embodiment can be replaced with an OLED panel. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

P1, P2, P3, P3: LCD Panel SIC, GIC: Drive IC
DL, GL: Bus Lines of LCD Panels

Claims (8)

A TFT array substrate having source bus lines supplied with a data signal, bus lines intersecting the source bus lines and gate bus lines supplied with a scan pulse, and a first sealant to face the TFT array substrate; A recycling method of a display panel including a color filter array bonded to a TFT array substrate and having a color filter formed thereon,
Cutting the display panel along a predetermined cutting surface to divide the display panel into two or more panel portions, and cutting the TFT array substrate larger than the color filter array substrate so that the bus lines are exposed at a portion of the display panel. A panel cutting process for forming a stepped cut surface in each of the panel portions;
A cut surface sealing process of joining the TFT array substrate and the color filter array substrate with a second sealant at a stepped cut surface of the panel portion;
A bus line exposing step of exposing the bus lines by removing the thin films formed on the bus lines at a portion of the stepped cut surface not coated with the second sealant; And
And a drive IC attaching process for attaching a drive IC or a flexible substrate to the bus lines exposed at the stepped cut surfaces. The method of claim 1,
And a module reassembly process of assembling the backlight unit on the panel portion to which the drive IC is adhered after the drive IC attaching process. The method of claim 1,
The drive IC attaching process,
Attaching an output terminal of a flexible circuit board to the bus lines exposed at the stepped cut surface using an anisotropic conductive film (ACF); And
And attaching the drive IC to the input terminals of the flexible circuit board by using the ACF. The method of claim 3, wherein
And a pitch between output terminals of the flexible printed circuit board is wider than a pitch between input terminals of the flexible printed circuit board. The method of claim 1,
The bus line exposure process,
Removing the thin film from the stepped cut surface by a chemical mechanical polishing (CMP) process, or removing the alignment film of the TFT array substrate with an etching solution of the alignment film; and
Removing the passivation layer of the TFT array substrate with an etchant of the passivation layer at the stepped cut surface to expose the source bus lines;
The drive IC attaching process,
And attaching a source drive IC for outputting the data signal to the source bus lines. The method of claim 5, wherein
The bus line exposure process,
Removing the source bus lines with an etchant of a source-drain metal at the stepped cut plane after removing the alignment layer and the protective layer; And
Exposing the gate bus lines by removing the gate insulating film and the semiconductor pattern covering the gate bus lines with the insulating film and the semiconductor etching solution from the stepped cut surface;
The drive IC attaching process,
And attaching a gate drive IC outputting the scan pulse to the gate bus lines. The method of claim 1,
The bus line exposure process,
And removing the thin film formed on the source bus lines and the gate bus lines by applying a chemical mechanical polishing (CMP) process and an etching process using an etchant. delete

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