JP2004118012A - Method for sticking polarizing plate to liquid crystal panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for sticking a polarizing plate to a liquid crystal panel by which fluctuation in the inspection accuracy for the preliminary visual inspection of the polarizing plate as a single body before sticking is prevented and the inspection can be accurately and efficiently carried out, failures in the liquid crystal panel with the polarizing plate stuck are prevented, and the yield of the liquid crystal cell is improved. <P>SOLUTION: The method for sticking a polarizing plate to a liquid crystal panel by using an adhesive layer 4 applied on one surface of the polarizing plate B to stick the polarizing plate B to the liquid crystal panel A includes the following processes. They are: a process of peeling a release paper 5 which protects the adhesive layer 4 on the polarizing plate B to expose the adhesive layer 4 just before the polarizing plate B is to be stuck to the liquid crystal panel A; a process of detecting foreign matters or flaws in the adhesive layer 4 of the polarizing plate B by using an appropriate inspection apparatus 18 after or while the release paper 5 is peeled from the polarizing plate B; and a process of immediately sticking only the polarizing plate B judged as a good product by the above inspection to the liquid crystal panel A. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for attaching a polarizing plate to a liquid crystal panel, and more particularly, to attaching a polarizing plate to a liquid crystal panel immediately after attaching the polarizing plate to a liquid crystal panel, after releasing (or peeling off) release paper from the polarizing plate. The present invention relates to a method of attaching a polarizing plate to a liquid crystal panel, in which a surface (adhesive surface) is inspected for defects such as foreign matter and flaws by an appropriate inspection device, and after inspection, only a polarizing plate determined to be non-defective is immediately attached to the liquid crystal panel.
[0002]
[Prior art]
In the process of manufacturing a liquid crystal unit, a method of pasting a polarizing plate to a liquid crystal panel, which has been conventionally performed, is a method in which a polarizing plate in which an adhesive layer is provided in advance on one surface of a liquid crystal panel is used. And two polarizing plates are attached to both surfaces of one liquid crystal panel to form a liquid crystal cell.
[0003]
As shown in FIG. 7, the polarizing plate B is an optical member that transmits only a specific polarization component with respect to incident light, and a polarizer 1 in which iodine or a dichroic dye is adsorbed and rolled on a polymer film, The two protective layers 2 for protecting both surfaces of the polarizer 1, a protective film 3 for covering the outer layer side of one protective layer 2, and the above-mentioned liquid crystal panel provided on the outer layer side of the other protective layer 2. A release paper 5 is adhered so as to cover the entire surface of the pressure-sensitive adhesive layer 4 in order to protect the pressure-sensitive adhesive layer 4 during storage.
[0004]
In the above-mentioned step of attaching the polarizing plate to the liquid crystal panel, in order to reduce defective products and improve the yield as much as possible, an optical or electrical inspection device is used, or the liquid crystal panel being manufactured by visual inspection or the like is used. The quality of the products is inspected as appropriate.
[0005]
For example, as described in Japanese Patent Application Laid-Open No. H10-31777, a defect inspection of a polarizing plate alone before pasting to a liquid crystal panel is disclosed. Inspection accuracy, presence of air bubbles, presence or absence of foreign matter, etc.) are also performed.
[0006]
By the way, a polarizing plate is shipped after the product inspection of a polarizing plate maker is completed, but 100% of the shipped polarizing plate is not necessarily a non-defective product. Therefore, a method of inspecting a polarizing plate in a delivered state as disclosed in Japanese Patent Application Laid-Open No. 9-229817 has been proposed.
[0007]
In this inspection method, a defect-free polarizing plate is interposed between a light source and a polarizing plate to be inspected, and inspection is performed while rotating the polarizing plate to be inspected. A protective sheet (release paper) is attached to the polarizing plate to be inspected. It is stated that a defect (defect) of the polarizing plate to be inspected can be detected even in the state where the mark is attached.
[0008]
[Problems to be solved by the invention]
However, the above-mentioned inspection method is a visual inspection by an operator after all, and the inspection is inefficient and varies, and the inspection is performed with the protective sheet (release paper) attached. There is a problem that the inspection accuracy is reduced.
[0009]
The inspected polarizing plates are stocked and then supplied to the polarizing plate sticking device. Then, in this sticking device, the supplied polarizing plate is first stripped of the release paper to expose the adhesive layer, and then is stuck to the liquid crystal panel.
[0010]
When peeling off the release paper from the polarizing plate, static electricity may be generated, so that there is a great possibility that foreign matters such as dust and dust floating near the release paper will adhere to the adhesive layer of the polarizing plate. This is because the room where the polarizing plate sticking device is located is a clean room.However, since it is impossible to completely eliminate foreign matter in machines and devices, the release paper is peeled off and the polarizing plate is attached to the liquid crystal panel. The longer the time until the attachment, the higher the rate of foreign matter adhering to the pressure-sensitive adhesive layer.
[0011]
Thus, even if the polarizing plate alone is inspected by the above-described inspection method and determined to be non-defective, in the next polarizing plate attaching step, after the release paper is peeled off and before the polarizing plate is attached to the liquid crystal panel. If the foreign matter adheres to the pressure-sensitive adhesive layer of the polarizing plate, the above-mentioned inspection is useless.
[0012]
If a defect such as a foreign substance is detected as a result of performing an inspection after attaching the polarizing plate to the liquid crystal panel, repair such as peeling the defective polarizing plate from the liquid crystal panel and attaching a non-defective polarizing plate again. Work is required. However, in this repair work, since the polarizing plate has high adhesiveness, it is not easy to peel off the polarizing plate once adhered. For this reason, when the polarizing plate is peeled off, the liquid crystal panel itself is seriously damaged, and as a result, the yield is hindered.
[0013]
Especially in recent years, as the size and definition of liquid crystal panels have increased, the burden and damage when peeling off the polarizers has increased, and it is important for liquid crystal panel manufacturers to solve the problem of sticking the polarizers to these panels. This is one of the major issues.
[0014]
Accordingly, an object of the present invention is to provide a method of attaching a polarizing plate to a liquid crystal panel, which eliminates the conventional defect inspection work of a polarizing plate alone, can increase the efficiency of a liquid crystal panel production process, and can save labor. It is an object of the present invention to provide a method of attaching a polarizing plate to a liquid crystal panel, in which the repair work after the attachment is eliminated by attaching the polarizing plate to the liquid crystal panel, thereby greatly improving the yield of the liquid crystal panel.
[0015]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention according to claim 1 is directed to a method of attaching a polarizing plate to a liquid crystal panel using an adhesive layer provided on one surface of the polarizing plate. Exposing the release layer to protect the pressure-sensitive adhesive layer of the polarizing plate immediately before attaching the polarizing plate to the panel to expose the pressure-sensitive adhesive layer, after releasing the release paper from the polarizing plate, or while peeling, The step of inspecting the pressure-sensitive adhesive layer of the plate for defects such as foreign matter and flaws using an appropriate inspection device, and the step of immediately attaching only the polarizing plate determined to be good as a result of the above inspection to the liquid crystal panel were adopted. Things.
[0016]
According to the above configuration, the pressure-sensitive adhesive layer is inspected by an inspection device after or while the release paper of the polarizing plate is peeled off, and if there is a defect such as a foreign substance or a flaw, the pressure-sensitive adhesive layer is not attached to the liquid crystal panel by discharging as it is. Since only non-defective products are attached to the liquid crystal panel, there is no need to perform a preliminary inspection of the polarizing plate or an inspection of the liquid crystal panel after the attachment, thereby improving the yield and reducing the cost.
[0017]
Further, the invention of claim 2 is that the release paper protecting the pressure-sensitive adhesive layer of the polarizing plate provided with the pressure-sensitive adhesive layer on one surface is peeled at the release paper peeling position, and the adhesive of the polarizing plate is adhered at the polarizing plate sticking position. In the method of attaching the polarizing plate to the liquid crystal panel using the agent layer, in the method of attaching the polarizing plate to the liquid crystal panel, a suitable inspection device was incorporated between the release sheet peeling position and the polarizing plate attaching position, and the release paper of the polarizing plate was peeled off. After or during peeling, the pressure-sensitive adhesive layer of the polarizing plate is inspected by the above-described inspection device, and only the polarizing plate determined as a good product as a result of the inspection is immediately attached to the liquid crystal panel.
[0018]
According to the above configuration, since an inspection device can be provided between the release sheet peeling position and the polarizing plate sticking position and integrated with the polarizing plate sticking device, no space is required, and after the release sheet of the polarizing plate is peeled off. Inspection can be performed when moving or peeling off, the time from peeling the release paper to pasting it on the liquid crystal panel can be shortened, and the adhesion of foreign matter such as dust in the air to the adhesive layer can be reduced. Can be prevented.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0020]
FIG. 1 is a plan view showing an entire polarizing plate sticking apparatus used for carrying out the method for sticking a polarizing plate to a liquid crystal panel according to the present invention.
[0021]
As shown, the polarizing plate sticking apparatus is divided into a front stage on the left side and a rear stage on the right side, and a processing line for the polarizing plate B and a polarizing plate sticking line for the liquid crystal panel A are provided on a horizontal machine base 11, respectively. A polarizing plate supply position a and a release sheet peeling position b are set on the processing line of the polarizing plate B, and a liquid crystal panel supply position c in the preceding stage is provided on the polarizing plate attaching line. In addition, a liquid crystal panel supply position c, a polarizer paste position d, and a liquid crystal cell discharge position f are set in a later stage, respectively.
[0022]
A liquid crystal panel supply line 12 faces the liquid crystal panel supply position c of the polarizing plate sticking line in the above-mentioned polarizing plate sticking apparatus, and the liquid crystal panel A that has gone through the cullet removing and cleaning steps supplies the liquid crystal panel with the liquid crystal panel supply line 12. It is sent to position c.
[0023]
Similarly, a polarizing plate storage box 13 for storing the polarizing plates B in a stacked state is provided at the polarizing plate supply position a of the processing line of the polarizing plate B in the preceding polarizing plate bonding apparatus.
[0024]
Two cylindrical brushes 14 facing each other are provided between the polarizing plate supply position a and the release paper peeling position b, and polarized light conveyed from the polarizing plate supply position a to the release paper peeling position b by appropriate means. The plate B passes between the two brushes 14 to remove dust and dirt on the surface.
[0025]
A release paper peeling device 16 that peels release paper from the polarizing plate B by a release paper peeling roller 15 is provided at the release paper peeling position b.
[0026]
Further, the polarizing plate B supplied from the polarizing plate storage box 13 is sucked and held on the upper surface thereof, and the release paper is peeled off by the release paper peeling device 16 to expose the surface adhesive layer. A polarizing plate suction table 17 for transferring the polarizing plate to the polarizing plate sticking position d of the line is arranged.
[0027]
The inspection for inspecting the surface of the polarizing plate B sucked and transferred to the polarizing plate suction table 17 between the release sheet peeling position b of the polarizing plate processing line and the polarizing plate sticking position d of the polarizing plate sticking line. An apparatus 18 is provided.
[0028]
At the liquid crystal panel supply position c of the polarizing plate sticking line, a liquid crystal panel A sent by the liquid crystal panel supply line 12 is sucked and held on its upper surface, and a liquid crystal panel supply table 19 that moves up a predetermined stroke after this sucking is provided. The sticking roller 20 is disposed below the polarizing plate sticking position d so that the sticking roller 20 moves up and down by the elevating means, and the liquid crystal panel A after the polarizing plate sticking is also adsorbed on the upper surface of the liquid crystal panel discharging position e. A holding liquid crystal panel discharge table 21 is provided.
[0029]
FIG. 2 is a front view taken along the arrow II of FIG. 1, and shows the entirety of a polarizing plate sticking line for sticking a polarizing plate B having an adhesive layer exposed on a liquid crystal panel A.
[0030]
As shown in the figure, the liquid crystal panel A is sucked and held by the lower surface on the upper part of the polarizing plate sticking line, and a horizontal space is provided between the liquid crystal panel supply table 19 at the liquid crystal panel supply position c and the liquid crystal panel discharge table 21. The liquid crystal panel suction table 22 is reciprocated, and the liquid crystal panel suction table 22 is stopped at the liquid crystal panel supply position c. In this state, the liquid crystal panel supply table 19 is raised and held on the upper surface of the liquid crystal panel supply table 19. When the liquid crystal panel A is pressed against the lower surface of the liquid crystal panel suction table 22 and the liquid crystal panel suction table 22 sucks the liquid crystal panel A, the liquid crystal panel supply table 19 is released and returns to the lowered position.
[0031]
Next, the liquid crystal panel suction table 22 on which the liquid crystal panel A is sucked on the lower surface moves to the polarizing plate sticking position d and stops, and the above-described polarizing plate suction table 17 moves immediately below the liquid crystal panel suction table 22. The liquid crystal panel A and the polarizing plate B are arranged so as to face up and down at the polarizing plate sticking position d.
[0032]
The function of attaching the polarizing plate B to the liquid crystal panel A will be described. First, as shown by a two-dot chain line in FIG. The tip is made to approach the lower surface of the liquid crystal panel A. In this state, the cylinder 24 is operated to raise the sticking roller 20, and the end of the polarizing plate B protruding from the polarizing plate suction table 17 is attached to the liquid crystal panel A by the sticking roller 20. Then, the pressure of the polarizing plate B by the polarizing plate suction table 17 is set to be weak, and the pressing force of the sticking roller 20 and the movement of the liquid crystal panel suction table 22 are prevented while preventing the polarizing plate B from falling off the inclined polarizing plate suction table 17. Due to the horizontal movement of the liquid crystal panel A accompanying the above, the polarizing plate B is attached to the liquid crystal panel A with the surface adhesive layer of the polarizing plate B.
[0033]
The pressing force of the cylinder 24 that pushes up the sticking roller 20 is controlled by the load sensor 25.
[0034]
When the liquid crystal panel suction table 20 stops at the liquid crystal panel discharge position e, the liquid crystal panel discharge table 21 rises, receives the liquid crystal panel A with the polarizing plate B stuck from the liquid crystal panel suction table 22, returns to the lowered position, and returns to the lower position. The table 22 returns to the liquid crystal panel supply position c.
[0035]
FIG. 3 is a front view taken along the arrow II-II of FIG. 1, wherein (A) shows the entire polarizing plate processing line, and (A), (B) and (C) show the release paper at the release paper peeling position b. It shows a peeled state sequentially.
[0036]
In the release paper peeling device 16, a release tape 26 having an adhesive layer on one side is wound around a release tape supply reel 28 together with a separate sheet 27 covering the surface of the adhesive layer. A plurality of rows (for example, two or three rows) are arranged and arranged on the right side of the polarizing plate B so as to have a width of the polarizing plate B as a whole. The adhesive layer of the release tape 26 was supplied downward to the upper surface of the polarizing plate suction table 17, and further disposed on the supply reel 28 via the release paper peeling roller 15 disposed on the left side position of the polarizing plate suction table 17. The tape is wound around a peeling tape winding reel 29.
[0037]
The release paper peeling roller 15 can be moved up and down by appropriate means at the end to a position indicated by a solid line and a position indicated by a two-dot chain line in FIG. 3 (A). 17 can be brought into contact with and separated from the vicinity of the end of the polarizing plate B placed thereon.
[0038]
Further, the release paper peeling roller 15 is horizontally movable in a direction perpendicular to its axis in a descending state in contact with the polarizing plate B, and is always urged to the left to maintain the tension state of the peeling tape 26. As the take-up reel 29 takes up, as shown in FIG. 3B, the peeling tapes 26 move while rotating to the right in the drawing along the upper surface of the polarizing plate B while keeping the tension state of the group. .
[0039]
Here, the step of removing the release paper 5 of the polarizing plate B will be described. First, as shown in FIG. 3A, the polarizing plate stored in the polarizing plate storage box 13 in the polarizing plate supply position a. B is taken out by an appropriate means and transported to the release paper peeling position b. At this time, the polarizing plate B passes between the two cylindrical brushes 14 to remove dust and dirt on the surface.
[0040]
The polarizing plate B transported to the polarizing plate suction table 17 in the release paper peeling device 16 at the release paper peeling position b is suctioned by the vacuum suction of the polarizing plate suction table 17.
[0041]
Next, the release paper peeling roller 15 is lowered by the elevating means, and the adhesive surface of the release tape 26 group wound around the release paper peeling roller 15 with the adhesive surface outside contacts the surface of one end of the polarizing plate B.
[0042]
Thereafter, as shown in FIG. 3B, when the release tape take-up reel 29 is rotated in the take-up direction while the release tape supply reel 28 is fixed, the release paper release tape 26 group is pulled toward the take-up reel 29. Accordingly, the release paper peeling roller 15 moves along the surface of the polarizing plate B from one end to the other end while rotating.
[0043]
At that time, since the adhesive force of the adhesive surface of the release paper release tape 26 group to the surface of the release paper 5 is stronger than the adhesive force of the adhesive layer 4 of the polarizing plate B, the release paper 5 is separated from the polarizing plate B. The release paper 5 adheres to the release tape 26 and moves, and the release paper 5 is completely released from the polarizing plate B as shown in FIG.
[0044]
FIG. 4 is a side view taken along the arrow III-III of FIG. 1. The polarizing plate B from which the release paper 5 has been peeled at the release paper peeling position b is held while being held by the polarizing plate suction table 17. 17 is moved to the polarizing plate attaching position d by the movement along the axis 23. At this time, the inspection device 18 inspects the surface for defects.
[0045]
The inspection device 18 includes a light source 31 and a line CCD camera 32. The light emitted from the light source 31 and reflected by the polarizing plate B is captured as an image by the line CCD camera 32, and the surface of the polarizing plate B (adhesive layer 4). Check for dust or dirt on the surface.
[0046]
FIG. 5 is a general block diagram of an inspection process performed by the inspection device 18. Light from a light source 31 transmitted (reflected in this embodiment) through a polarizing plate B is input to a line CCD camera 32. The image is captured as an analog signal image, the analog signal is converted into a digital signal by A / D conversion, image pre-processing is performed in real time as a filter function such as noise removal, and further image processing is performed, and then monitored by an image display device. At the same time, the host computer determines defects due to the presence of scratches on the surface of the polarizing plate B or the presence of foreign matter such as dust or dirt, and determines the quality of the defect. Non-defective products are conveyed to the polarizing plate sticking position d as they are. The sticking operation to the liquid crystal panel A is performed, and the defective product, which is confirmed to be defective, is removed from the polarizing plate sticking position d by appropriate means (not shown). Is, joining work to the liquid crystal panel A at the polarizing plate joining position d is not performed.
[0047]
The polarizing plate B determined to be non-defective by the inspection of the inspection device 18 is affixed to the liquid crystal panel A at the polarizing plate affixing position d, and is inverted from the liquid crystal panel discharge table 21 at the liquid crystal panel discharging position e to be a liquid crystal panel at the subsequent stage. It is supplied on the supply table 19.
[0048]
The latter-stage polarizing plate sticking device performs the same processing steps as the above-mentioned first-stage polarizing plate sticking device once again, and pastes the polarizing plate B on the other surface of the liquid crystal panel A. The same parts are denoted by the same reference numerals and description will be omitted.
[0049]
FIGS. 6A and 6B are front views taken along arrows IV-IV in FIGS. 1A and 1B, wherein FIGS. 6A and 6B show the peeling state of the release paper and the inspection state of the polarizing plate B between the release paper peeling position b and the polarizing plate attaching position d. Are sequentially shown.
[0050]
In the release paper peeling device 16, a release tape 26 having an adhesive layer on one side is wound around a release tape supply reel 28 together with a separate sheet 27 covering the surface of the adhesive layer. A plurality of rows (for example, two or three rows) are arranged and arranged on the right side of the polarizing plate B so as to have a width of the polarizing plate B as a whole. The adhesive layer of the release tape 26 was supplied downward to the upper surface of the polarizing plate suction table 17, and further disposed on the supply reel 28 via the release paper peeling roller 15 disposed on the left side position of the polarizing plate suction table 17. The tape is wound around a peeling tape winding reel 29.
[0051]
The release paper peeling roller 15 can be moved up and down by appropriate means at the end to a position indicated by a solid line and a position indicated by a two-dot chain line in FIG. 6 (A). 17 can be brought into contact with and separated from the vicinity of the end of the polarizing plate B placed thereon.
[0052]
Here, the step of peeling the release sheet 5 of the polarizing plate B will be described. First, the polarized light stored in the polarizing plate storage box 13 in the polarizing plate supply position a in the subsequent polarizing plate attaching apparatus shown in FIG. The plate B is taken out by appropriate means and transported to the release sheet peeling position b. At this time, the polarizing plate B passes between the two cylindrical brushes 14 to remove dust and dirt on the surface.
[0053]
The polarizing plate B transported to the polarizing plate suction table 17 in the release paper peeling device 16 at the release paper peeling position b is suctioned by the vacuum suction of the polarizing plate suction table 17.
[0054]
Next, the release paper peeling roller 15 is lowered by the elevating means, and the adhesive surface of the release tape 26 wound around the release paper peeling roller 15 with the adhesive surface outside contacts the surface of one end of the polarizing plate B.
[0055]
Thereafter, as shown in FIG. 6B, while the position of the peeling roller 15 is fixed, the polarizing plate suction table 17 is moved to the polarizing plate sticking position d side, and the peeling tape winding reel 29 is also moved in the winding direction. When the release tape supply reel 28 is also rotated freely and the release tape 26 is sent out, the release paper release roller 15 is rotated at a fixed position, and the adhesive surface of the release tape 26 group is applied to the entire surface of the polarizing plate B which moves. Press.
[0056]
At that time, since the adhesive force of the adhesive surface of the release paper release tape 26 group to the surface of the release paper 5 is stronger than the adhesive force of the adhesive layer 4 of the polarizing plate B, the release paper 5 is separated from the polarizing plate B. The release paper 5 adheres to the release tape 26 and moves, and the release paper 5 peels off from the polarizing plate B.
[0057]
At the same time, the polarizing plate B, which moves together with the polarizing plate suction table 17, reflects the light from the light source 31 of the inspection device 18, transfers an image of the surface to the line CCD camera 32, and displays the surface of the polarizing plate B (the adhesive layer 4). ) Is checked based on the block diagram shown in FIG. 5, and the host computer determines defects due to scratches on the surface of the polarizing plate B or the presence of foreign matter such as dust or dust. Pass / fail is determined, and a non-defective product is transported to the polarizing plate attaching position d as it is, and is adhered to the liquid crystal panel A, and a defective product for which a defect is confirmed is appropriately determined from the polarizing plate attaching position d by means (not shown). ), And is not attached to the liquid crystal panel A at the polarizing plate attaching position d.
[0058]
According to the configuration of the above-described polarizing plate sticking device, the release paper 5 is peeled off as the polarizing plate suction table 17 moves to the polarizing plate sticking position d, and at the same time, the adhesion of the polarizing plate B immediately after peeling is performed by the inspection device 18. Since the agent layer 4 can be inspected and the operation of attaching the liquid crystal panel A to the liquid crystal panel A can be performed continuously, the operation time is shortened and the operation efficiency is improved. Can be attached in a short time, thereby reducing the possibility that dust or dirt in the air adheres during that time.
[0059]
The release plate is peeled off and the polarizing plate B determined to be non-defective by the inspection device 18 is provided on the back surface of the liquid crystal panel A on which the polarizing plate B has not yet been bonded by the same process as FIG. The polarizing plate B is attached. The liquid crystal panel discharge position e composed of the liquid crystal panel discharge table 21 in FIG. 2 in the preceding stage is the liquid crystal cell discharge position f composed of the liquid crystal cell discharge table 33 in the subsequent stage.
[0060]
After the above-mentioned first and second processing steps, the liquid crystal panel A having the polarizing plates B adhered to both sides becomes a liquid crystal cell C, and is moved from the liquid crystal panel suction table 22 to the liquid crystal cell discharge table 33 at the latter liquid crystal cell discharge position f. Then, a liquid crystal cell discharge line 34 is arranged, and the liquid crystal cell C is transferred to a mounting process such as a TCP and an FPC through the liquid crystal cell discharge line 34.
[0061]
In the above-described embodiment, in the release paper peeling device 16 in the first stage, the release roller 15 moves in the horizontal direction with respect to the polarizing plate B and peels the release paper 5. Although the release roller 15 is fixed and the release paper 5 is peeled off as the polarizing plate B moves, any release paper release device may be used for both the first and second stages, and the same release paper is used for both the first and second stages. Device 16 can also be used.
[0062]
【The invention's effect】
As described above, according to the present invention, after releasing the release paper from the polarizing plate, or while peeling, the adhesive layer of the polarizing plate is inspected by the inspection device to remove defective products. Among the polarizing plates obtained, defective polarizing plates that originally had defects such as scratches and impurities such as dust and dust in the adhesive layer, and dust and dust in the air after peeling off release paper Defective products taken into the layer can be eliminated immediately before pasting to the liquid crystal panel, so that the prior inspection of the polarizing plate alone can be omitted, and defects in the liquid crystal cell due to defects in the polarizing plate Can be prevented beforehand, and the yield can be improved.
[0063]
In addition, by arranging the inspection device between the release position of the release paper and the polarizing plate sticking position, the space efficiency of the whole device is improved, and the inspection can be performed immediately after the release paper is released, and further to the liquid crystal panel. The time required between peeling the release paper and pasting it to the LCD panel is shortened, and there is less danger of taking in dust and dirt in the air due to static electricity when the release paper is peeled off, which reduces the yield. improves.
[Brief description of the drawings]
FIG. 1 is a plan view of a polarizing plate sticking apparatus for carrying out a method of sticking a polarizing plate to a liquid crystal panel according to the present invention; FIG. 2 is an enlarged front view taken along the arrow II of FIG. 1 FIG. FIG. 4 is an enlarged front view along arrows II-II, in which (A), (B), and (C) sequentially show the release state of the release paper. FIG. 4 is an enlarged side view along arrows III-III in FIG. FIG. 6 is a block diagram showing an example of the inspection apparatus. FIG. 6 is an enlarged side view taken along the arrow IV-IV of FIG. 1, wherein (A) and (B) sequentially show the release state of the release paper and the inspection state. Cross-sectional side view showing an example of the configuration of a polarizing plate.
Reference Signs List A Liquid crystal panel B Polarizing plate C Liquid crystal cell 1 Polarizer 2 Protective layer 3 Protective film 4 Adhesive layer 5 Release paper 11 Machine stand 12 Liquid crystal panel supply line 13 Polarizer storage box 14 Brush 15 Release paper peeling roller 16 Release paper peeling device Reference Signs List 17 Polarizing plate suction table 18 Inspection device 19 Liquid crystal panel supply table 20 Sticking roller 21 Liquid crystal panel discharge table 22 Liquid crystal panel suction table 23 Shaft 24 Cylinder 25 Load sensor 26 Peeling tape 27 Separate sheet 28 Peeling tape supply reel 29 Peeling tape winding reel 30 Guide roll 31 Light source 32 Line CCD camera 33 Liquid crystal cell discharge table 34 Liquid crystal cell discharge line a Polarizer supply position b Release paper peeling position c Liquid crystal panel supply position d Polarizer attachment position The liquid crystal panel discharge position f the liquid crystal cell discharge position

Claims (2)

In the method of attaching a polarizing plate to a liquid crystal panel using an adhesive layer provided on one surface of the polarizing plate, the adhesive layer of the polarizing plate is protected immediately before attaching the polarizing plate to the liquid crystal panel. Exposing the pressure-sensitive adhesive layer by peeling off the release paper, after peeling off the release paper from the polarizing plate, or while peeling off the pressure-sensitive adhesive layer of the polarizing plate by using an appropriate inspection device using a suitable inspection device. A method of adhering a polarizing plate to a liquid crystal panel, comprising the steps of: (a) inspecting the defect; and (b) immediately adhering only the polarizing plate determined as a non-defective product as a result of the inspection to the liquid crystal panel. At the release paper release position, release the release paper protecting the pressure-sensitive adhesive layer of the polarizing plate provided with the adhesive layer on one surface, and use the pressure-sensitive adhesive layer of the polarizing plate at the polarizing plate attachment position to apply the liquid crystal to the polarizing plate. In the method of attaching the polarizing plate to the liquid crystal panel to be attached to the panel, incorporating an appropriate inspection device between the release sheet peeling position and the polarizing plate sticking position, after peeling the release paper of the polarizing plate or while peeling the polarizing plate. A method of attaching a polarizing plate, wherein the pressure-sensitive adhesive layer is inspected by the above-described inspection device, and only the polarizing plate determined as a good product as a result of the inspection is immediately attached to the liquid crystal panel.

Images