JP2006171061A - Luminance spot defect repairing method of polarizing plate for liquid crystal panel, and liquid crystal display using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a luminance spot repairing method of a polarizing plate for a liquid crystal panel by which a luminance spot defect caused by a polarizing plate (or a polarizing plate with an adhesive layer) which constitutes the liquid crystal panel can be repaired, a liquid crystal is not deteriorated, the area and the thickness of a light shielding part can be easily controlled without changing the total thickness of the liquid crystal panel and falling of a repaired part at the time of handling or the like after repair can be prevented. <P>SOLUTION: The luminance spot defect repairing method for repairing the luminance spot defect generated in the polarizing plate 100 for the liquid crystal panel provided with a polarizing plate 1 and an adhesive layer 2 provided on at least one surface side of the polarizing plate 1 includes a first step for forming a recessed part 3 (or a through hole) at a part of the adhesive layer 2 corresponding to the luminance spot defect and a second step for filling the recessed part 3 (or the through hole) with a light shielding material 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method of repairing a bright spot defect (white defect) generated in a polarizing plate for a liquid crystal panel by making it a black spot, and a liquid crystal display device equipped with a polarizing plate for a liquid crystal panel repaired using this method.

  In recent years, liquid crystal display devices are becoming larger, extremely thin, and higher in density (higher definition). Therefore, it is inevitable that display defects (pixel defects) occur in units of pixels in the manufacturing process and the like. It is a situation. Such pixel defects often have white display (bright spots) when light emitted from the backlight passes through the liquid crystal panel and leaks outside when black display is performed on the liquid crystal display device. Therefore, it is necessary to repair (repair) the defect. Such pixel defects (bright spot defects) are caused by various kinds of damage such as scratches on members constituting the liquid crystal panel mounted on the liquid crystal display device, contamination of foreign substances and air layers when assembling the liquid crystal panel, and short-circuiting of the switching elements. Caused by the cause.

Here, as a conventional bright spot defect repairing method, for example, (1) a method of disconnecting a short circuit portion of a switching element such as a TFT (thin film transistor) corresponding to the bright spot defect (refer to the column of prior art in Patent Document 1) (2) A method of disturbing or controlling the alignment regulating force of the liquid crystal layer by irradiating a portion of the liquid crystal panel corresponding to the bright spot defect to control the amount of transmitted light (Patent Document 2, Patent) Document 3), (3) A method of applying a light-blocking photocurable resin (ink) to a portion corresponding to a bright spot defect on the surface of a liquid crystal panel (polarizing plate surface) (see Patent Document 4), etc. has been proposed. Yes.
JP-A 63-240521 JP-A-60-243635 JP-A-8-146370 JP-A-7-181438

  However, the repair method (1) has a problem that only a short circuit portion of the switching element can be repaired (only a bright spot defect caused by a short circuit of the switching element can be repaired). Further, in the repair method (2), there is a problem in that the liquid crystal is deteriorated in the laser light irradiated portion and the reliability is lowered and the light is not completely shielded. Furthermore, in the repair method of (3) above, the total thickness of the liquid crystal panel is increased due to the increased thickness of the ink to be applied, which is contrary to the demand for ultra-thinning, and the area and thickness of the ink to be applied (light shielding portion). There are problems that it is difficult to control the surface area and thickness), and that the applied ink may be rubbed off during handling in the manufacturing process.

  The present invention has been made to solve such problems of the prior art, and can repair bright spot defects caused by a polarizing plate (or a polarizing plate with an adhesive layer) constituting a liquid crystal panel. At the same time, the area and thickness of the light-shielding part can be easily controlled without degrading the liquid crystal and without changing the total thickness of the liquid crystal panel, and it is also possible to prevent missing repaired parts during handling after repairing. It is an object of the present invention to provide a method for repairing a bright spot defect of a certain polarizing plate for a liquid crystal panel and a liquid crystal display device equipped with a polarizing plate for a liquid crystal panel repaired by using this method.

  The inventors of the present invention have intensively studied to solve the above problems, and as a result, if a portion corresponding to a bright spot defect in a polarizing plate for a liquid crystal panel (or a polarizing plate with an adhesive layer) is filled with a light shielding material, The present inventors have found that the problem can be solved and have completed the present invention.

  That is, the present invention is a method for repairing bright spot defects generated in a polarizing plate for a liquid crystal panel comprising a polarizing plate and an adhesive layer provided on at least one surface of the polarizing plate, the adhesive layer A polarizing plate for a liquid crystal panel, comprising: a first step of forming a concave portion or a through hole in a portion corresponding to a bright spot defect in the first step; and a second step of filling a light shielding material into the concave portion or the through hole. A method for repairing bright spot defects on a plate is provided.

  According to such an invention, the part corresponding to the bright spot defect in the adhesive layer provided on the polarizing plate (the adhesive layer intersecting with the straight line extending in the normal direction of the polarizing plate from the part where the cause of the bright spot defect occurs). When the backlight is applied to the liquid crystal panel to which the polarizing plate for the liquid crystal panel is mounted after the light shielding material is filled, the light emitted from the backlight is applied to the liquid crystal panel. When transmitting, light is always blocked (blackened) at the portion filled with the light blocking material, and it is possible to repair the bright spot defect. In addition, the liquid crystal panel is not in the state of a liquid crystal panel laminated, but in the state of a single polarizing plate for a liquid crystal panel, a concave portion or a through hole is formed in the adhesive layer, and this is filled with a light shielding material. The liquid crystal is not deteriorated without being affected, the thickness of the polarizing plate for the liquid crystal panel is not changed, and the total thickness of the liquid crystal panel is not changed. Furthermore, by appropriately adjusting the size of the recess or the through hole, the area and thickness of the light shielding part (filled part of the light shielding material) can be easily controlled, and the restoration part (light shielding part) can be prevented from being lost. is there.

  Further, in order to solve the above problems, the present invention is a method for repairing a bright spot defect generated in a polarizing plate for a liquid crystal panel, wherein a concave portion or a through hole is formed in a portion corresponding to the bright spot defect in the polarizing plate. And a second step of filling the concave portion or the through hole with a light-shielding material. The method is also provided as a bright spot defect repairing method for a polarizing plate for a liquid crystal panel.

  Also according to such an invention, the same effect as the case where the light shielding material is filled in the concave portion or the through hole formed in the adhesive layer is obtained.

  Preferably, in the second step, after the light shielding material is filled into a partial region of the recess or the through hole, the remaining region is further filled with a protective material.

  According to such a configuration, after the light shielding material is filled in the partial region of the recess or the through hole, the remaining region is further filled with the protective material, so that the thickness of the polarizing plate for the liquid crystal panel is not changed. The surface of the light-shielding material is coated with the protective material (without changing the total thickness of the liquid crystal panel), and the repaired state can be reliably maintained.

  In the case where it includes a first step of forming a recess or a through hole in a portion corresponding to a bright spot defect in the adhesive layer and a second step of filling the recess or the through hole with a light shielding material, preferably the second step In the process, after the light shielding material is filled into a partial region of the recess or the through hole, the remaining region is further filled with an adhesive material.

  According to such a configuration, since the adhesive material is further filled in the remaining region after the light shielding material is filled in the partial region of the recess or the through hole, the thickness of the polarizing plate for the liquid crystal panel is not changed. The surface of the light-shielding material is coated with the adhesive material (without changing the total thickness of the liquid crystal panel), so that the repaired state can be reliably maintained and the adhesive function of the adhesive layer can be maintained. The advantage of not harming at all is obtained.

  Preferably, in the first step, a recess or a through hole is formed using a laser beam.

  According to such a configuration, since the concave portion or the through hole is formed using the laser beam, the size (area, thickness) of the concave portion or the through hole can be easily controlled by appropriately adjusting the size and energy density of the laser spot. In addition, the concave portion or the through hole can be easily positioned by appropriately adjusting the irradiation position of the laser spot.

  As the laser beam, one having an ultraviolet wavelength is preferably used.

  According to such a configuration, since the laser light has a wavelength in the ultraviolet region, it is possible to suppress degradation of the portion other than the recess or the through hole formed in the polarizing plate for the liquid crystal panel, and the laser spot can be narrowed down to reduce the laser spot. Or it is possible to make the dimension of a through-hole small as needed.

  As the light-shielding material, various curable resins such as an ultraviolet curable resin and a thermosetting resin, a metal paste, or a resin having adhesiveness temporarily or with time can be used.

  Note that the present invention is also provided as a liquid crystal display device including a polarizing plate for a liquid crystal panel repaired by the bright spot defect repairing method.

  According to the present invention, the portion corresponding to the bright spot defect in the adhesive layer (or the polarizing plate) provided on the polarizing plate (crossed with the straight line extending in the normal direction of the polarizing plate from the portion causing the bright spot defect) When the backlight is irradiated to the liquid crystal panel to which the polarizing plate for a liquid crystal panel is attached after the light shielding material is filled, the backlight is backlit. When the light irradiated from the light passes through the liquid crystal panel, the light is always shielded (black spots) at the portion filled with the light shielding material, and the bright spot defect can be repaired. In addition, the liquid crystal panel is not in the state of a liquid crystal panel laminated, but in a state of a single polarizing plate for a liquid crystal panel, a concave portion or a through hole is formed in the adhesive layer (or polarizing plate), and this is filled with a light shielding material. Therefore, the liquid crystal is not deteriorated without affecting the liquid crystal, the thickness of the polarizing plate for the liquid crystal panel is not changed, and the total thickness of the liquid crystal panel is not changed. Furthermore, by appropriately adjusting the size of the recess or the through hole, the area and thickness of the light shielding part (filled part of the light shielding material) can be easily controlled, and the restoration part (light shielding part) can be prevented from being lost. is there.

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

<First Embodiment>
FIG. 1 is a longitudinal sectional view showing a schematic configuration of a polarizing plate for a liquid crystal panel in a state where the bright spot defect repairing method according to the first embodiment of the present invention is applied. As shown in FIG. 1A, a polarizing plate 100 for a liquid crystal panel according to the present embodiment is provided on the polarizing plate 1 and at least one surface side of the polarizing plate 1 (only one surface side in the present embodiment). An adhesive layer 2 is provided.

  In the bright spot defect repairing method according to the present embodiment, first, a portion corresponding to the bright spot defect in the adhesive layer 2 (crossing with a straight line extending in the normal direction of the polarizing plate 100 from the portion where the cause D of the bright spot defect occurs). A concave portion or a through hole (in this embodiment, the concave portion 3) is formed in the adhesive layer 2 portion to be formed.

  More specifically, in the present embodiment, a method of irradiating a portion of the adhesive layer 2 corresponding to the bright spot defect with laser light and forming the recess 3 or the through hole by ablation processing with the laser light is applied. ing. Note that the size of the laser spot of the irradiated laser beam (corresponding to the area of the formed recess 3 or through-hole) can be adjusted by an appropriate optical system such as an aperture or a condenser lens, but it is bright at the irradiation position. It is preferably set to 1.1 to 10 times the size of the point defect (the size of the observed bright spot). Various laser light sources such as an excimer laser, a YAG laser, a CO2 laser, and a femtosecond laser can be used as the laser light source that emits the laser light, but the adhesive layer 2 constituting the polarizing plate 100 for the liquid crystal panel. In view of the fact that it is possible to suppress deterioration of members other than the above and deterioration of parts other than the part where the concave portion 3 is formed in the adhesive layer 2, and to narrow down the laser spot, the oscillation wavelength in the ultraviolet region (for example, 193 nm) can be reduced. It is preferable to use a laser light source.

  Next, in the bright spot defect repairing method according to this embodiment, the light shielding material 4 is filled into the formed recesses 3 or through holes.

  More specifically, in the present embodiment, the filling is performed while controlling the coating amount of the light shielding material 4 using a dispenser or an inkjet. Various materials can be applied as the light-shielding material 4 as long as they have the property of shielding the light emitted from the backlight. For example, adhesive / adhesive materials, dye / pigment inks, heat / ultraviolet curing It is also possible to fill a multilayer with a plurality of mixed materials in addition to the conductive resin and the metal paste. Further, from the viewpoint of not harming the adhesive function of the adhesive layer 2, it is preferable to use a resin having adhesive properties temporarily or continuously as the light shielding material 4.

  In addition, as shown in FIG. 1B, after the light-shielding material 4 is filled in a partial region in the depth direction of the formed recess 3 or through hole, the remaining region is further filled with the protective material 5. Is also possible. According to such a configuration, the surface of the light shielding material 4 is a protective material without changing the thickness of the polarizing plate for liquid crystal panel 100 (and thus without changing the total thickness of the liquid crystal panel including the polarizing plate for liquid crystal panel 100). It is possible to reliably hold the repaired state. Although it does not specifically limit as the protective material 5, For example, an adhesive material and a thermo / photocurable resin can be used suitably. Various materials such as acrylic, rubber-based, urethane-based, epoxy-based, and polyimide-based materials can also be used.

  Further, as shown in FIG. 1C, after the light shielding material 4 is filled into a partial region in the depth direction of the formed recess 3 or through-hole, an adhesive material 6 (for example, an adhesive layer) is formed in the remaining region. It is also possible to further fill the same adhesive material as the material constituting 2). Even in such a configuration, the surface of the light-shielding material 4 is not changed in the adhesive material 6 without changing the thickness of the polarizing plate 100 for the liquid crystal panel (and thus without changing the total thickness of the liquid crystal panel including the polarizing plate 100 for the liquid crystal panel). It is possible to reliably hold the repaired state and the adhesive material 6 exhibits an adhesive function, so that the adhesive function of the adhesive layer 2 is not adversely affected.

  As shown in FIG. 2, the polarizing plate 100 for a liquid crystal panel after being repaired by the bright spot defect repairing method according to the present embodiment described above is formed by laminating a glass substrate 7a, a liquid crystal layer 8, and a glass substrate 7b. A liquid crystal panel is assembled by bonding to the liquid crystal cell 200 thus configured (not shown, but a polarizing plate is actually bonded to the opposite surface of the liquid crystal cell 200).

  According to the bright spot defect repairing method according to the present embodiment, since the portion corresponding to the bright spot defect in the adhesive layer 2 provided on the polarizing plate 1 is filled with the light shielding material 4, When the backlight is applied to the liquid crystal panel (see FIG. 2) to which the polarizing plate 100 for the liquid crystal panel is attached, the portion filled with the light shielding material 4 when the light emitted from the backlight passes through the liquid crystal panel. Therefore, light is always blocked (turns to a black spot), and it is possible to repair bright spot defects. In addition, the liquid crystal panel 8 is not in the state of the liquid crystal panel, but the liquid crystal panel polarizing plate 100 is in a single state, and the concave portion 3 or the through hole is formed in the adhesive layer 2 and the light shielding material 4 is filled therein. For this reason, the liquid crystal is not deteriorated without affecting the liquid crystal, and the thickness of the polarizing plate 100 for the liquid crystal panel is not changed, so that the total thickness of the liquid crystal panel is not changed. Furthermore, by appropriately adjusting the size of the recess 3 or the through-hole, the area and thickness of the light-shielding part (filled part of the light-shielding material 4) can be easily controlled, and the restoration part (light-shielding part) can be prevented from being lost. Is possible.

  In particular, in the bright spot defect repairing method according to the present embodiment, the concave portion 3 or the through hole is formed using laser light, so that the size of the laser spot or the energy density is appropriately adjusted to adjust the size of the concave portion 3 or the through hole. The dimensions (area and thickness) can be easily controlled, and the concave portion 3 or the through hole can be easily positioned by appropriately adjusting the irradiation position of the laser spot.

  It should be noted that as to which part of the pressure-sensitive adhesive layer 2 included in the polarizing plate for liquid crystal panel 100 should have the recess 3 or the through hole (which part corresponds to a bright spot defect), the bright spot defect cause D Can be directly recognized visually (for example, when two polarizing plates 100 are overlapped), the concave portion 3 or the through-hole is formed in a portion corresponding to the portion where the bright spot defect cause D occurs. That's fine. In addition, when the bright spot defect cause D cannot be directly recognized visually, a liquid crystal panel including the polarizing plate 100 for the liquid crystal panel is temporarily assembled (for example, the respective members are stacked without being bonded), and the backlight is attached thereto. After the portion corresponding to the bright spot defect is identified by irradiating light from the liquid crystal, only the liquid crystal panel polarizing plate 100 is removed to form the recess 3 or the through hole in the portion corresponding to the identified bright spot defect. That's fine. In any case, as described above, a concave portion 3 or a through hole is formed in the adhesive layer 2 in the state of the liquid crystal panel polarizing plate 100 alone, not in the state of the liquid crystal panel, and the light shielding material 4 is filled therein. Therefore, there is an advantage that the liquid crystal is not deteriorated without affecting the liquid crystal.

Second Embodiment
FIG. 3 is a longitudinal sectional view showing a schematic configuration of a polarizing plate for a liquid crystal panel in a state where the bright spot defect repairing method according to the second embodiment of the present invention is applied. As shown in FIG. 3, the polarizing plate 300 for a liquid crystal panel according to this embodiment is configured to include only the polarizing plate 1 described in the first embodiment.

  In the bright spot defect repair method according to the present embodiment, first, a portion corresponding to the bright spot defect in the polarizing plate 1 (crossing with a straight line extending in the normal direction of the polarizing plate 300 from the portion where the cause D of the bright spot defect occurs). A concave portion or a through hole (in this embodiment, the concave portion 3) is formed in a portion of the polarizing plate 1 to be processed.

  More specifically, a method of applying a laser beam to a portion corresponding to a bright spot defect in the polarizing plate 1 and forming the recess 3 or the through hole by ablation processing with the laser beam is applied. Note that the size of the laser spot of the irradiated laser beam (corresponding to the area of the recessed portion 5 or the through hole formed) can be adjusted by an appropriate optical system such as an aperture or a condenser lens. It is preferably set to 1.1 to 10 times the size of the point defect (the size of the observed bright spot). Since the laser light source that emits the laser light is the same as that of the first embodiment, the description thereof is omitted.

  Next, in the bright spot defect repair method according to the present embodiment, the light shielding material 4 is filled into the formed recesses 3 or through-holes as in the first embodiment. In addition, since the filling method of the light shielding material 4 and the kind of the light shielding material 4 are the same as those in the first embodiment, the description thereof is omitted.

  As for the bright spot defect repairing method according to the present embodiment, as in the first embodiment, after the light shielding material 4 is filled into a partial region in the depth direction of the formed recess 3 or through hole, the remaining portion is repaired. It is possible to further fill the area with a protective material 5. With this configuration, the surface of the light-shielding material 4 is the protective material 5 without changing the thickness of the polarizing plate for liquid crystal panel 300 (and without changing the total thickness of the liquid crystal panel including the polarizing plate for liquid crystal panel 300). It will be covered, and the repaired state can be reliably maintained.

  As shown in FIG. 4, the polarizing plate 300 for a liquid crystal panel after being repaired by the bright spot defect repairing method according to the present embodiment described above is coated with the adhesive material 2 on at least one surface side of the polarizing plate 1. Alternatively, after the casting, the glass substrate 7a, the liquid crystal layer 8, and the glass substrate 7b are laminated and bonded to the liquid crystal cell 200, thereby assembling a liquid crystal panel (not shown, but actually the liquid crystal panel is omitted). A polarizing plate is also bonded to the opposite surface of the cell 200).

  According to the bright spot defect repairing method according to the present embodiment, since the light shielding material 4 is filled in the portion corresponding to the bright spot defect in the polarizing plate 1, the liquid crystal panel polarizing plate 300 after filling the light shielding material 4 is provided. When the attached liquid crystal panel (see FIG. 4) is irradiated with a backlight, when the light emitted from the backlight passes through the liquid crystal panel, the light is always blocked at the portion filled with the light shielding material 4 (see FIG. 4). It becomes possible to repair bright spot defects. Further, the liquid crystal panel 8 is not in the state of the liquid crystal panel, but in the state of the liquid crystal panel polarizing plate 300 alone, the concave portion 3 or the through hole is formed in the polarizing plate 1, and the light shielding material 4 is filled therein. For this reason, the liquid crystal is not deteriorated without affecting the liquid crystal, and the thickness of the polarizing plate 300 for the liquid crystal panel is not changed, so that the total thickness of the liquid crystal panel is not changed. Furthermore, by appropriately adjusting the size of the recess 3 or the through-hole, the area and thickness of the light-shielding part (filled part of the light-shielding material 4) can be easily controlled, and the restoration part (light-shielding part) can be prevented from being lost. Is possible.

  Further, in the bright spot defect repairing method according to the present embodiment, since the recess 3 or the through hole is formed using laser light, the size of the recess 3 or the through hole (by adjusting the size and energy density of the laser spot as appropriate). (Area, thickness) can be easily controlled, and the positioning of the recess 3 or the through hole can be easily performed by appropriately adjusting the irradiation position of the laser spot.

  It should be noted that the bright spot defect cause D depends on which part of the polarizing plate 1 included in the polarizing plate 300 for the liquid crystal panel should have the recess 3 or the through hole (which part corresponds to the bright spot defect). Can be directly recognized visually, the concave portion 3 or the through hole may be formed at a site corresponding to the location where the bright spot defect cause D occurs. In addition, when the bright spot defect cause D cannot be directly recognized visually, a liquid crystal panel including the polarizing plate 300 for the liquid crystal panel is temporarily assembled, and the portion corresponding to the bright spot defect is irradiated with light from the backlight. Then, only the polarizing plate for liquid crystal panel 300 may be removed, and the recess 3 or the through hole may be formed in a portion corresponding to the specified bright spot defect. In any case, as described above, the concave portion 3 or the through hole is formed in the polarizing plate 1 not in the state of the liquid crystal panel but in the state of the polarizing plate 300 for the liquid crystal panel, and the light shielding material 4 is filled therein. Therefore, there is an advantage that the liquid crystal is not deteriorated without affecting the liquid crystal.

  In the bright spot defect repairing method according to the first embodiment and the second embodiment described above, the method of forming the concave portion 3 or the through hole using laser light has been described as a preferred mode, but the present invention is not limited to this. Instead of this, it is also possible to form the recess 3 or the through hole by using a drilling tool such as a drill or applying a chemical etching method.

  Hereinafter, the features of the present invention will be further clarified by showing examples and comparative examples.

<Example 1>
A liquid crystal panel in which a white display (observed as a white display (bright spot) of about φ150 μm) occurs during black display due to a foreign matter having a size of about φ50 μm existing in the adhesive layer 2 shown in FIG. A polarizing plate 100 was prepared. A portion corresponding to the bright spot defect in the adhesive layer 2 was irradiated with a laser beam having a wavelength of 193 nm using an excimer laser to form a recess 3 having a depth of about 10 μm. The size of the laser spot (corresponding to the area of the recess) on the irradiated surface of the irradiated laser light was about 200 μm, and the energy density was about 2.0 J / cm ² . Next, using a dispenser, the black oil-based ink 4 as a light-shielding material was filled in the recesses 5 until the depth of 10 μm was filled, and the bright spot defects were repaired by drying and curing at room temperature for 3 hours.

  When the liquid crystal panel is assembled by attaching the liquid crystal panel polarizing plate 100 after repairing the bright spot defect according to this embodiment, and light is irradiated from the backlight, the black oil-based ink 4 always blocks the light. As a result, white display could be prevented (black spots). Further, the adhesive function of the adhesive layer 2 could be easily bonded to the liquid crystal cell without harming. Further, as compared with the conventional method of simply applying ink to the surface of the polarizing plate, the concave portion 3 is formed as a guide for filling the ink 4 with laser light. Therefore, by appropriately adjusting the position and dimensions of the concave portion 3, The area and thickness of the repaired part (light-shielding part) and the positioning of the repaired part can be determined very easily, and the total thickness of the liquid crystal panel including the repaired part does not change at all before and after the repair.

<Example 2>
A bright spot defect of the polarizing plate for a liquid crystal panel was repaired under the same conditions as in Example 1 except that a UV (ultraviolet) YAG laser was used as a laser light source and a laser beam having a wavelength of 355 nm was irradiated to form a recess. Also in this example, the same effect as in Example 1 could be achieved.

<Example 3>
The bright spot defect of the polarizing plate for a liquid crystal panel was repaired under the same conditions as in Example 1 except that a UV (ultraviolet) YAG laser was used as a laser light source and a laser beam having a wavelength of 266 nm was irradiated to form a recess. Also in this example, the same effect as in Example 1 could be achieved.

<Example 4>
A bright spot defect of the polarizing plate for a liquid crystal panel was repaired under the same conditions as in Example 1 except that a UV (ultraviolet) YAG laser was used as a laser light source and a laser beam having a wavelength of 213 nm was irradiated to form a recess. Also in this example, the same effect as in Example 1 could be achieved.

<Example 5>
The bright spot defect of the polarizing plate for a liquid crystal panel was repaired under the same conditions as in Example 1 except that an excimer laser was used as a laser light source and a laser beam having a wavelength of 248 nm was irradiated to form a recess. Also in this example, the same effect as in Example 1 could be achieved.

<Example 6>
The bright spot defect of the polarizing plate for liquid crystal panel was repaired under the same conditions as in Example 1 except that a concave portion was formed at a site corresponding to the bright spot defect in the polarizing plate 1 of the polarizing plate 100 for liquid crystal panel. Also in this example, the same effect as in Example 1 could be achieved.

<Comparative example>
Bright spot defects were repaired by applying ink to the surface of the adhesive layer of the polarizing plate for liquid crystal panel used in Example 1 before repairing the bright spot defects so that the thickness was 10 μm and the diameter was about φ200 μm.

  When the liquid crystal panel was assembled by laminating the polarizing plate for a liquid crystal panel after repairing the bright spot defect according to this comparative example to the liquid crystal cell, the total thickness of the liquid crystal panel increased by about 5 μm before and after the repair. In addition, when the repaired polarizing plate for a liquid crystal panel is bonded to the liquid crystal cell, the ink application part (restoration part) is displaced and the repaired liquid crystal panel is irradiated with light from the backlight. As for the peripheral part, light leaked to the outside, and white display could not be completely prevented (black spot). In other words, when the light-shielding material having the same dimensions as in Example 1 was applied to the luminescent spot defect under the same conditions as in Example 1, the luminescent spot defect could not be completely repaired.

FIG. 1 is a longitudinal sectional view showing a schematic configuration of a polarizing plate for a liquid crystal panel in a state where the bright spot defect repairing method according to the first embodiment of the present invention is applied. FIG. 2 is an explanatory diagram for explaining a process of assembling a liquid crystal panel using a polarizing plate for a liquid crystal panel to which the bright spot defect repair method according to the first embodiment of the present invention is applied. FIG. 3 is a longitudinal sectional view showing a schematic configuration of a polarizing plate for a liquid crystal panel in a state where the bright spot defect repairing method according to the second embodiment of the present invention is applied. FIG. 4 is an explanatory diagram for explaining a process of assembling a liquid crystal panel using a polarizing plate for a liquid crystal panel to which the bright spot defect repairing method according to the second embodiment of the present invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Polarizing plate 2 ... Adhesive layer 3 ... Recessed part (or through-hole)
DESCRIPTION OF SYMBOLS 4 ... Light-shielding material 5 ... Protective material 6 ... Adhesive material 7a, 7b ... Glass substrate 8 ... Liquid crystal layer 100, 300 ... Polarizing plate for liquid crystal panels 200 ... Liquid crystal cell D ... Causes of bright spot defects

Claims (10)

A method of repairing bright spot defects generated in a polarizing plate for a liquid crystal panel comprising a polarizing plate and an adhesive layer provided on at least one surface side of the polarizing plate,
A first step of forming a recess or a through hole at a site corresponding to a bright spot defect in the adhesive layer;
A second step of filling the concave portion or the through hole with a light shielding material;
A method of repairing a bright spot defect in a polarizing plate for a liquid crystal panel, comprising: A method for repairing bright spot defects generated in a polarizing plate for a liquid crystal panel,
A first step of forming a recess or a through hole at a site corresponding to a bright spot defect in the polarizing plate;
A second step of filling the concave portion or the through hole with a light shielding material;
A method of repairing a bright spot defect in a polarizing plate for a liquid crystal panel, comprising:   3. The liquid crystal panel according to claim 1, wherein in the second step, after a light shielding material is filled in a partial region of the recess or the through hole, a protective material is further filled in the remaining region. Method for repairing bright spot defects in polarizing plates for use in an automobile.   2. The polarized light for a liquid crystal panel according to claim 1, wherein in the second step, after a light shielding material is filled in a partial region of the recess or the through hole, an adhesive material is further filled in the remaining region. A method for repairing bright spot defects on plates.   5. The method for repairing a bright spot defect in a polarizing plate for a liquid crystal panel according to claim 1, wherein in the first step, a recess or a through hole is formed using a laser beam.   6. The bright spot defect repairing method for a polarizing plate for a liquid crystal panel according to claim 5, wherein the laser light has a wavelength in the ultraviolet region.   The method for repairing a bright spot defect in a polarizing plate for a liquid crystal panel according to claim 1, wherein the light shielding material is an ultraviolet curable resin.   The method for repairing a bright spot defect in a polarizing plate for a liquid crystal panel according to claim 1, wherein the light shielding material is a thermosetting resin.   7. The method for repairing a bright spot defect in a polarizing plate for a liquid crystal panel according to claim 1, wherein the light shielding material is a metal paste.   A liquid crystal display device comprising a polarizing plate for a liquid crystal panel repaired by the bright spot defect repairing method according to claim 1.

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