KR20080038739A - Polarizer removal film and polarizer removal method of liquid crystal display panel - Google Patents

Abstract

A polarizer removal film and a polarizer removing method of a liquid crystal display panel are provided to reduce a fabrication unit cost by removing the necessity of discarding the entire liquid crystal panel because of a defect generated in reworking a polarizer. An adhesive layer(220) is formed on one surface of a polymer film(210) and has an adhesive strength. A protection film(230) is formed on the adhesive layer to protect the adhesive layer. The polymer film is made of at least one of materials selected from among compounds such as polypropylene, polyethylene terephthalate, polystyrene, polyvinyl alcohol, polymetal methacrylate, nylon. The thickness of the polymer film is the same as or smaller than that of a polarizer.

Description

POLARIZER REMOVAL FILM AND POLARIZER REMOVAL METHOD OF LIQUID CRYSTAL DISPLAY PANEL}

1 is a cross-sectional view showing that a polarizing plate removing film is formed for removing a polarizing plate attached to a liquid crystal display panel according to an exemplary embodiment of the present invention.

FIG. 2 is a perspective view illustrating the liquid crystal display panel of FIG. 1.

3 is a cross-sectional view illustrating a structure of the upper polarizing plate of FIGS. 1 and 2.

4 is a cross-sectional view showing the structure of a film for removing a polarizing plate according to an embodiment of the present invention.

5 is a block diagram sequentially illustrating a method of removing a polarizer of a liquid crystal display panel according to an exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

20: liquid crystal display panel 30: liquid crystal

40 thin film transistor substrate 100 color filter substrate

150: upper polarizing plate 160,161: polarizing film

170,171: support film 180,181: adhesive layer

190: lower polarizing plate 200: film for removing the polarizing plate

210: polymer film 220: adhesive layer

230: protective film

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizing plate removing method of a polarizing plate removing film and a liquid crystal display panel, and more particularly, to a polarizing plate removing film and a liquid crystal display panel removing method capable of facilitating removal of a defective polarizing plate.

A liquid crystal display device is an apparatus which displays an image by adjusting the light transmittance of a liquid crystal using an electric field. To this end, the liquid crystal display panel includes a color filter substrate and a thin film transistor substrate bonded to each other with the liquid crystal interposed therebetween. Then, the liquid crystal molecules are moved by a magnetic field generated by applying a voltage to the electrodes between the two substrates, thereby displaying an image due to the light transmittance which varies accordingly.

In the liquid crystal display, polarizers are attached to upper and lower substrates of the liquid crystal panel to control the polarization state of incident light.

The polarizing plate is formed by adhering an adhesive layer to a polarizing film, and attaching a release film on the adhesive layer to protect the adhesive layer. The polarizing plate is attached to the liquid crystal display panel through the adhesive layer after removing the release film.

In order to reduce the cost of the polarizer, researches are being conducted to reduce the thickness of the TAC (triacetylcellulose) film used as the protective layer and the retardation layer of the polarizer.

When attaching such a polarizing plate to a liquid crystal panel, there are problems such as bubbles or wrinkles. In this case, it is necessary to rework to remove and reattach the polarizer.

As a result of the decrease in the thickness of the polarizing plate, when the defect of the polarizing plate is generated and needs to be reworked, there is a problem in that the entire liquid crystal panel is discarded because it is not torn or completely removed when the polarizing plate is removed.

Accordingly, the technical problem of the present invention is to provide a polarizing plate removing film and a removing method for preventing defects occurring when the polarizing plate reworking using the polarizing plate removing film.

In order to achieve the above technical problem, the polarizing plate removal film of the present invention is a polymer film; An adhesive layer formed on one surface of the polymer film and having an adhesive force; It is characterized by comprising a protective film formed on the pressure-sensitive adhesive layer to protect the pressure-sensitive adhesive layer.

The material of the polymer film is formed of at least one material selected from compounds such as polypropylene, polyethylene terephthalate, polystyrene, polyvinyl alcohol, polymetal methacrylate, and nylon.

The thickness of the polymer film is characterized in that the same as or smaller than the thickness of the polarizing plate.

In order to achieve the above technical problem, the polarizing plate removal method of the liquid crystal display panel of the present invention comprises the steps of inspecting the defects of the upper and lower polarizers attached to the upper and lower portions of the liquid crystal panel; Attaching a polarizing plate removing film to at least one of the upper and lower polarizing plates when the defect occurs; It characterized in that it comprises the step of peeling the polarizing plate removal film and the polarizing plate in which the defect occurred.

And if the defects do not occur in the upper and lower polarizers in the step of inspecting the defects of the upper and lower polarizers, transferring the liquid crystal panel to the next process.

Other objects and features of the present invention in addition to the above object will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a cross-sectional view showing that a polarizing plate removing film is formed for removing a polarizing plate attached to a liquid crystal display panel according to an exemplary embodiment of the present invention.

Referring to FIG. 1, in order to explain a method of removing the polarizers 150 and 190 of the liquid crystal display panel 20, the liquid crystal display panel 20, the defective polarizers 150 and 190 and the defective polarizers 150 and 190 are removed. It includes a polarizing plate removal film 200 for.

FIG. 2 is a perspective view illustrating the liquid crystal display panel of FIG. 1.

Referring to FIG. 2, the liquid crystal display panel 20 includes a thin film transistor substrate 40 and a color filter substrate 100 bonded to each other with the liquid crystal 30 interposed therebetween.

The liquid crystal 30 is made of a material having dielectric anisotropy and refractive index anisotropy, and a pixel voltage from the pixel electrode 90 of the thin film transistor substrate 40 and a common voltage from the common electrode 140 of the color filter substrate 100. The light transmittance is adjusted by rotating by the difference of.

The thin film transistor substrate 40 includes a gate line 60 and a data line 70 formed on the lower substrate 50 to cross each other, the thin film transistor 80 adjacent to the intersection portion, and a pixel region provided in the crossing structure. And a pixel electrode 90 formed on it.

The gate line 60 applies a scan signal to the gate electrode of the thin film transistor 80. The data line 70 applies a data voltage to the source electrode of the thin film transistor 80.

The thin film transistor 80 applies a data voltage supplied from the data line 70 to the pixel electrode 90 in response to a scan signal supplied from the gate line 60. To this end, the thin film transistor 80 may include a gate electrode connected to the gate line 60, a source electrode connected to the data line 70, a drain electrode positioned to face the source electrode, and connected to the pixel electrode 90. And an active layer forming a channel between the source electrode and the drain electrode, and an ohmic contact layer for ohmic contact between the source electrode and the drain electrode.

The pixel electrode 90 charges itself with the pixel voltage according to the data voltage supplied from the thin film transistor 80 to generate a potential difference with the common electrode 140 formed on the color filter substrate 100. Due to the potential difference, the liquid crystal 30 positioned between the thin film transistor substrate 40 and the color filter substrate 100 is rotated by the dielectric anisotropy, and the amount of light incident from the backlight assembly via the pixel electrode 90 is adjusted. The light is transmitted toward the color filter substrate 100.

The color filter substrate 100 includes a black matrix 120, a color filter 130, and a common electrode 140 sequentially formed on the upper substrate 110.

The black matrix 120 divides the upper substrate 110 into a plurality of cell regions in which the color filter 130 is formed, and prevents light interference and external light reflection between adjacent cells. To this end, the black matrix 120 is formed on the upper substrate 110 to overlap at least one of the data line 70, the gate line 60, and the thin film transistor 80 formed on the lower substrate 50. .

The color filter 130 is formed to be divided into red (R), green (G), and blue (B) in the cell region divided by the black matrix 120 to transmit red, green, and blue light, respectively.

The common electrode 140 supplies a common voltage Vcom which is a reference when driving the liquid crystal 30 to the transparent conductive layer.

The upper polarizer 150 is disposed on the liquid crystal display panel 20, and the lower polarizer 190 is disposed below the liquid crystal display panel 20.

3 is a cross-sectional view illustrating a structure of the upper polarizing plate of FIGS. 1 and 2.

Referring to FIG. 3, the upper polarizer 150 may include polarizers 160 that absorb light in a specific direction, and support layers 170 and 171 having angles disposed on both sides of the polarizer 160 with the polarizer 160 therebetween. ). The upper polarizer 150 is adhered to the liquid crystal display panel 20 by an adhesive layer 180 positioned between the liquid crystal display panel 20 and the upper polarizer 150.

The polarizing film 160 is formed by stretching while heating a thin film of polyvinyl alcohol to deposit iodic acid in a dichroic dye solution. The polarizing film 160 has a stretching axis that is in the stretching direction and a transmission axis that is perpendicular to the stretching axis.

The polarizing film 160 is typically formed of a polymer film. Polymer films include PolyVinyl Alchoil (PVA), Polyethylene Terephthalate (PET), PolyVinyl Butyral (PVB), etc. Among them, polyvinyl alcohol has excellent effect in enhancing in-plane uniformity. In addition, the polarizing film 160 is excellent in dyeing affinity for iodine.

The upper polarizing plate 150 having the polarizing film 160 has a stretching axis (absorption axis) that is a direction in which the polarizing film 160 is stretched, and a transmission axis (polarization axis) orthogonal to the stretching axis. For this reason, the polarizing film 160 of the upper polarizing plate 150 divides incident light into two polarizing components orthogonal to each other to absorb or disperse one component and transmit the other component. The polarizing film 160 of the upper polarizing plate 150 has a thickness of several to several hundred um.

The support films 170 and 171 are disposed on both side surfaces of the polarizing film 160 having the properties of polyvinyl alcohol having a high water affinity and iodine having sublimability. The support layers 170 and 171 of the upper polarizer 150 have a thickness of several to several hundred um.

Since the configuration and characteristics of the lower polarizer 190 are the same as those of the upper polarizer 150, a detailed description thereof will be omitted.

In addition, a retardation film may be formed on at least one of the upper and lower polarizers 150 and 190. The retardation film compensates the viewing angle in the direction perpendicular to the liquid crystal display panel 20 and the direction of the viewing angle change, thereby widening the region without gray inversion, and increasing the contrast ratio in the oblique direction. One may be formed of a negative uniaxial film or a negative biaxiak film having two optical axes, but a negative biaxial film is more preferable in terms of wide viewing angle.

4 is a cross-sectional view showing the structure of a film for removing a polarizing plate according to an embodiment of the present invention.

Referring to FIG. 4, the polarizing plate removing film 200 includes a polymer film 210, an adhesive layer 220, and a protective film 230.

Specifically, the material of the polymer film 210 is polypropylene (PolyPropylene; PP), polyethylene terephthalate (PolyEthylene Terephthalate (PET), polystyrene (PS), polyvinyl alcohol (PolyVinyl Alchol; PA), polymetal methacrylate It is formed of at least one material selected from compounds such as polymethyl methacrylate (PMMA) and nylon (Nylon). In addition, the thickness of the polymer film 210 is formed equal to or smaller than the thickness of the polarizing plate (150, 190). Preferably it is 50 to 500um. Here, if the thickness of the polymer film 210 is formed to 50um or less, the thickness is too thin, the strength is not guaranteed. On the other hand, if formed to more than 500um, the strength according to the thickness is guaranteed but the manufacturing cost increases.

The adhesive layer 220 is made of an adhesive of a poly acrylate (Poly Acrylate (PA)) system having excellent adhesion, and is applied to one side of the polymer film 210. The thickness of the adhesive layer 220 is preferably formed, for example, 20um.

Here, to improve the adhesive strength of the pressure-sensitive adhesive may be added to the corona treatment (Corona).

Corona treatment uses high-frequency electrical discharges on the surface of the polymer material to increase the wettability of the surface. The low surface energy of polymer materials causes adhesion problems in inks, adhesives and coatings, which is solved by increasing the surface energy of the workpiece higher than the material. Therefore, the corona treatment increases the wettability on the surface of the adhesive layer 220 to improve the adhesive strength.

The protective film 230 for protecting the adhesive layer 220 formed as described above is attached.

5 is a block diagram sequentially illustrating a method of removing a polarizer of a liquid crystal display panel according to an exemplary embodiment of the present invention.

Referring to FIG. 5, the method of removing a polarizing plate of a liquid crystal panel according to an exemplary embodiment of the present invention includes preparing a liquid crystal panel (S1), attaching a polarizing plate to the liquid crystal panel (S2), and checking whether the polarizing plate is defective. And a step (S10) of removing the polarizer if a defect occurs in the polarizing plate, and a step (S4) of transferring the liquid crystal panel to the next process if the defect does not occur in the polarizing plate.

The upper and lower polarizers 150 and 190 attached to the upper and lower portions of the liquid crystal display panel 20 prepared as described above are checked.

For example, the failure of the polarizers 150 and 190 may be caused by the presence of foreign matter on the surfaces of the polarizers 150 and 190, or the occurrence of scratches, or when the polarizers 150 and 190 are attached to the upper and lower portions of the liquid crystal display panel 20. If entered.

When a defect occurs in the polarizing plates 160 and 190, the polarizing plates are removed (S10). Removing the polarizing plate (S10) includes providing a film for removing the polarizing plate (S11), attaching the polarizing plate removing film to the polarizing plate in which the defect has occurred (S12), and removing the polarizing plate and the film removing step for removing the polarizing plate (S13). The polarizer is attached to the liquid crystal panel (S2) again.

Removing the polarizing plate removal film 200, the polarizing plate removal film 200 formed of the polymer film 210, the adhesive layer 220, the protective film 230 to the polarizing plate (150, 190) is defective After attaching, the polarizing plates 150 and 190 and the polarizing plate removing film 200 are simultaneously removed.

The polymer film 210 may be made of polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl alcohol (PA), and polymetal methacrylate (PolyMethyl). It is formed of at least one material selected from compounds such as methacrylate (PMMA) and nylon. In addition, the thickness of the polymer film 210 is formed to be the same as or smaller than the thickness of the polarizing plate (150,190). Preferably it is 50 to 500um. Here, if the thickness of the polymer film 210 is formed to 50um or less, the thickness is too thin, the strength is not guaranteed. On the other hand, if formed to more than 500um, the strength according to the thickness is guaranteed but the manufacturing cost increases.

The adhesive layer 220 is made of a poly acrylate (Poly Acrylate (PA))-based adhesive having an adhesive force, and is applied to one side of the polymer film 210. The thickness of the adhesive layer 220 is preferably formed, for example, 20um. Then, the protective film 230 for protecting the adhesive force of the adhesive layer 220 is applied on the adhesive layer 220 to form a film 200 for removing the polarizing plate.

When the failure occurs in the polarizers 150 and 190 by determining whether the upper and lower polarizers 150 and 190 are defective, the polarizing plate removal film 200 formed as described above is attached to the polarizers 150 and 190 where the failure occurs.

Thereafter, the polarizing plates 150 and 190 and the polarizing plate removing film 200 are simultaneously peeled from the liquid crystal display panel 20.

Specifically, starting from one edge portion of the polarizing plate 150,190 and the polarizing plate removing film 200 attached on the liquid crystal display panel 20, it starts to peel off and is completely removed.

When reworking the polarizers 150 and 190 in which defects are generated in this manner, the tearing defects do not occur when the polarizers 150 and 190 are removed.

Accordingly, in the present invention, in order to solve the problems caused by the thinning of the polarizing plate, by separately manufacturing the polarizing plate removal film 200 and attaching to the polarizing plate (150,190) in which the failure occurs, the polarizing plate (150,190) and the film for removing the polarizing plate ( When the thicknesses of the 200 are combined to reinforce the strength, the polarizers 150 and 190 may not be completely removed or the defects such as tearing may not occur when the polarizers 150 and 190 are reworked.

Through this process, the liquid crystal display panel 20 from which the polarizing plates 150 and 190 are removed is subjected to a sequential process again.

On the other hand, if the failure of the upper and lower polarizers (150, 190) to determine whether the failure in the polarizers (150, 190) is transferred to the next process to go through the process according to the order.

As mentioned above, the polarizing plate removal method of the polarizing plate removal film and liquid crystal display panel which concerns on this invention can provide the polarizing plate removal film, and can easily remove the polarizing plate which a defect generate | occur | produced.

The polarizing plate removing film according to the present invention is provided with a polarizing plate removing film separately in order to solve the problems caused by the thinning of the polarizing plate and attached to the polarizing plate where the defect occurs, resulting in sufficient thickness of the polarizing plate where the defect is generated. It can prevent the defect that occurs during work.

Therefore, it is not necessary to discard the entire liquid crystal panel due to defects generated during reworking of the polarizing plate, thereby reducing manufacturing costs.

Although the detailed description of the present invention described above has been described with reference to a preferred embodiment of the present invention, those skilled in the art or those with ordinary knowledge in the technical field, the present invention described in the claims to be described later It is apparent that various modifications and changes can be made in the present invention without departing from the spirit and scope of the invention.

Claims (5)

A polymer film; An adhesive layer formed on one surface of the polymer film and having an adhesive force; And a protective film formed on the adhesive layer to protect the adhesive layer. The method of claim 1, The material of the polymer film is a film for removing a polarizing plate, characterized in that formed of at least one material selected from compounds such as polypropylene, polyethylene terephthalate, polystyrene, polyvinyl alcohol, polymetal methacrylate, nylon. The method of claim 2, The thickness of the polymer film is a film for removing a polarizing plate, characterized in that less than or equal to the thickness of the polarizing plate. Inspecting whether the upper and lower polarizers attached to the upper and lower parts of the liquid crystal panel are defective; Attaching a polarizing plate removing film to at least one of the upper and lower polarizing plates when the defect is generated; Peeling the film for removing the polarizing plate and the polarizing plate in which the defect is generated. The method of claim 4, wherein Inspecting the defects of the upper and lower polarizers And transferring the liquid crystal panel to a next process if a defect does not occur in the upper and lower polarizers.

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