JP2014167547A - Method of manufacturing image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of manufacturing an image display device excellent in a camera performance in high production efficiency.SOLUTION: A method of manufacturing an image display device includes the steps of: laminating a polarizer which is formed with a resin film containing a dichroic substance at least on one side of a picture display panel having a mark can be recognized from outside; and forming a decolorization part in a part of the polarizer, using the mark provided in the picture display panel as an alignment reference.

Description

  The present invention relates to a method for manufacturing an image display device.

  An image display device such as a mobile phone or a notebook personal computer (PC) is usually equipped with a camera. Various studies have been made for the purpose of improving the camera performance of such an image display device (for example, Patent Document 1). However, with the rapid spread of smartphones and touch panel type information processing devices, further improvement in camera performance is desired.

JP 2011-81315 A

  The present invention has been made to solve the above-described conventional problems, and a main object thereof is to provide a method capable of manufacturing an image display device excellent in camera performance with high production efficiency.

  The inventors of the present invention have developed an image display device having excellent camera performance by forming a decoloring portion at a portion corresponding to the camera hole portion of an image display device on which the polarizer is mounted to improve transparency. It was found that it can be obtained. Furthermore, by forming a decoloring part on the polarizer in a state of being stacked on the image display panel using the mark provided on the image display panel as a positioning reference, the positional accuracy of the decoloring part is remarkably improved. The inventors have found that the object can be achieved and have completed the present invention.

According to the present invention, a method for manufacturing an image display device is provided. The method for manufacturing an image display device according to the present invention includes a step of laminating a polarizer composed of a resin film containing a dichroic material on at least one side of an image display panel having a mark recognizable from the outside, and the lamination A step of forming a decoloring portion on a part of the polarizer using a mark provided in the image display panel as an alignment reference is included.
In preferable embodiment, the said decoloring part respond | corresponds to the camera hole part of the image display apparatus manufactured.
In preferable embodiment, the said decoloring part is formed by irradiation of a laser beam.
In a preferred embodiment, the laser light includes light having a wavelength of at least 1500 nm.
In a preferred embodiment, the laser is a solid state laser.
In a preferred embodiment, the polarizer is laminated on at least one side of the image display panel with a protective film laminated on at least one side thereof.
In a preferred embodiment, the method for manufacturing an image display device of the present invention includes a step of dividing a large image display panel into a predetermined size before the step of laminating.
In a preferred embodiment, the method for manufacturing an image display device of the present invention includes a step of attaching an electronic circuit for driving the image display panel to the image display panel after the step of forming the decoloring portion.

  According to the present invention, the decoloring unit and the camera hole unit of the image display device are formed on the polarizer laminated on the image display panel by forming the decoloring unit using the mark provided on the image display panel as an alignment reference. Is easy to align, and the positional accuracy is improved. As a result, since the transparency of the camera hole portion can be easily ensured at a high level, an image display device having excellent camera performance can be obtained with high production efficiency.

It is the schematic explaining the mark with which an image display panel is provided. It is the schematic explaining the procedure which determines the formation position of a decoloring part in this invention.

  The method for manufacturing an image display device according to the present invention includes a step of laminating a polarizer made of a resin film containing a dichroic substance on at least one side of an image display panel having a mark recognizable from the outside (hereinafter referred to as “lamination”). And a step of forming a decoloring part on a part of the laminated polarizer and using a mark provided on the image display panel as an alignment reference (hereinafter, referred to as a “decoloring step”). )including. As described above, an image display device having excellent camera performance can be obtained by forming a decoloring portion in a portion corresponding to the camera hole portion of the image display device on which the polarizer is mounted. However, when a part of a polarizer (or a polarizing film having a protective film laminated on at least one side thereof), for example, an edge portion is used as an alignment reference, it is more accurate due to the influence of chipping, cracking, bending, stretching, etc. of the end portion. In some cases, the position is not calculated and a decoloring portion is formed at a position shifted from a desired position. Further, when a decoloring part is formed on the polarizer and then laminated on the image display panel, the decoloring part may be further deviated from a desired position as a result of alignment between the polarizer and the image display panel. On the other hand, according to the manufacturing method of the present invention, such a problem can be avoided and the decoloring part can be accurately formed at a desired position.

  Examples of the image display device manufactured by the manufacturing method of the present invention include a liquid crystal display device and an organic EL display device. Preferably, these image display devices are equipped with cameras.

[Lamination process]
In the stacking step, a polarizer is stacked on at least one side of an image display panel having a mark that can be recognized from the outside.

  The said polarizer is comprised from the resin film containing a dichroic substance, for example, dye | stains a resin film with a dichroic substance, and is obtained by extending | stretching. The polarizer is usually laminated on the image display panel in a state of a polarizing film in which a protective film is laminated on at least one side thereof.

  Any appropriate resin can be used as the resin for forming the resin film. Preferably, polyvinyl alcohol resin (hereinafter referred to as “PVA resin”) is used. Examples of the PVA resin include polyvinyl alcohol and ethylene-vinyl alcohol copolymer. Polyvinyl alcohol is obtained by saponifying polyvinyl acetate. An ethylene-vinyl alcohol copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer. The saponification degree of the PVA resin is usually 85 mol% or more and less than 100 mol%, preferably 95.0 mol% to 99.95 mol%, more preferably 99.0 mol% to 99.93 mol%. is there. The saponification degree can be determined according to JIS K 6726-1994. By using a PVA-based resin having such a saponification degree, a polarizer having excellent durability can be obtained. If the degree of saponification is too high, there is a risk of gelation. The resin film may be a resin layer (PVA resin layer) formed on a resin base material. According to such a form, a thin polarizer (for example, 10 micrometers or less) can be obtained.

  The average degree of polymerization of the PVA-based resin can be appropriately selected according to the purpose. The average degree of polymerization is usually 1000 to 10000, preferably 1200 to 4500, more preferably 1500 to 4300. The average degree of polymerization can be determined according to JIS K 6726-1994.

  Examples of the dichroic substance include iodine and organic dyes. These may be used alone or in combination of two or more. Preferably, iodine is used.

  The dyeing with iodine is performed, for example, by immersing the resin film in an iodine aqueous solution. Any appropriate method can be adopted as a stretching method of the stretching treatment. Specifically, free end stretching or fixed end stretching may be used. The stretching direction can also be set as appropriate, and may be, for example, the longitudinal direction of the long resin film or the width direction of the long resin film. The draw ratio is typically 3 to 7 times. The stretching may be performed after the dyeing treatment or may be performed while dyeing. Moreover, you may dye | stain after extending | stretching. If necessary, the resin film is subjected to swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like. For example, by immersing the resin film in water before washing and washing it with water, not only can the dirt on the surface of the resin film and the anti-blocking agent be washed, but also swelling of the resin film to prevent uneven dyeing, etc. Can do.

  The polarizer preferably exhibits absorption dichroism in the wavelength range of 380 nm to 780 nm. The single transmittance (Ts) of the polarizer is preferably 40% or more, more preferably 41% or more, still more preferably 42% or more, and particularly preferably 43% or more. The theoretical upper limit of the single transmittance is 50%, and the practical upper limit is 46%. Further, the single transmittance (Ts) is a Y value measured with a 2 degree visual field (C light source) of JIS Z8701 and corrected for visibility, for example, using a microspectroscopic system (Lambda Vision, LVmicro). Can be measured. The polarization degree of the polarizer is preferably 99.8% or more, more preferably 99.9% or more, and further preferably 99.95% or more.

  The thickness of the polarizer can be set to any appropriate value. The thickness is typically about 1 μm to 80 μm, preferably 30 μm or less. The thinner the thickness, the better the decolorization part can be formed. For example, in laser light irradiation described later, the absorbance per unit film thickness is high, and a decolorized portion can be formed efficiently.

  Examples of the material for forming the protective film include cellulose resins such as diacetyl cellulose and triacetyl cellulose, (meth) acrylic resins, cycloolefin resins, olefin resins such as polypropylene, and ester resins such as polyethylene terephthalate resins. , Polyamide resins, polycarbonate resins, copolymer resins thereof, and the like.

  The surface of the protective film where the polarizer is not laminated may be subjected to a treatment for the purpose of a hard coat layer, antireflection treatment, diffusion or antiglare as a surface treatment layer. For example, the surface treatment layer is preferably a layer having a low moisture permeability for the purpose of improving the humidification durability of the polarizer.

  The thickness of the protective film is preferably 20 μm to 100 μm. The protective film is typically laminated on the polarizer via an adhesive layer (specifically, an adhesive layer or an adhesive layer). The adhesive layer is typically formed of a PVA adhesive. The pressure-sensitive adhesive layer is typically formed of an acrylic pressure-sensitive adhesive.

  If necessary, a pressure-sensitive adhesive layer and a release liner may be provided on the side of the protective film where the polarizer is not laminated.

  Examples of the image display panel include a liquid crystal panel and an organic EL panel. Preferably, it is a sheet-like image display panel obtained by dividing a large image display panel (so-called mother board) into a predetermined size.

  The mark provided in the image display panel is not limited as long as it can be recognized from the outside. Here, the mark recognizable from outside means a mark recognizable from outside by any image recognition technology such as a transparent camera. As illustrated in FIG. 1A, a substrate (for example, a color filter substrate or an array substrate) 11 that constitutes the image display panel 10 is usually bonded accurately to each other, which usually determines the cutting position accurately. From such a viewpoint, the alignment mark 20 is printed in advance. Further, as illustrated in FIG. 1B, in the color filter substrate 12, a display unit 22 composed of R, G, and B pixels and a black matrix of pixel gaps is usually displayed on the glass substrate 21 as an image display. It is formed with an area corresponding to the apparatus, and a black matrix outer frame 23 is formed around it. Therefore, if such a boundary line between the alignment mark 20 or the display unit 22 and the black matrix 23 of the outer frame is used as a mark, it is advantageous in that it is not necessary to separately provide a new mark. The shape and size of the alignment mark can be any suitable shape and size. From the viewpoint of more accurately determining the irradiation position, the image display panel preferably includes a plurality of alignment marks. In addition, a characteristic panel wiring or the like can be used as a mark. Further, a mark for alignment reference of the decoloring part may be separately provided on the image display panel by means such as printing.

  There is no restriction | limiting in particular as a method of laminating | stacking a polarizer on an image display panel, Arbitrary appropriate methods are employ | adopted. Typically, a polarizer is laminated | stacked on an image display panel through an adhesive layer in the state of a polarizing film. For example, from a long polarizing film having an adhesive layer and a release liner in this order on the side of the protective film on which the polarizer is not laminated, a polarizing film having a shape corresponding to the size of the image display panel or a shape larger than that is used. Punching is performed by peeling the release liner from the obtained sheet-like polarizing film, and laminating it on one surface of the image display device via an adhesive layer. When laminating on both sides, a sheet-like polarizing film may be similarly bonded to the other side. At this time, they may be bonded so that the absorption axis directions of the polarizers are orthogonal to each other, may be bonded so as to be parallel, or may be bonded so as to define any appropriate angle. Bonding of such a polarizing film and an image display panel can be suitably performed using any appropriate apparatus (for example, JP-A-2005-305999).

  In the stacking step, it is preferable to sequentially stack polarizers on both sides of the image display panel from the viewpoint of manufacturing efficiency. However, it is also possible to stack the polarizer only on one side (for example, the viewing side) of the image display panel. . In that case, after the decoloring process described later, a second stacking process for stacking the polarizer on the other side (for example, the backlight side) can be performed in the same manner as the first stacking process. In addition, when a polarizing film larger than the size of the panel is laminated on the image display panel, the excess polarizing film is cut before or after the decoloring process described later or simultaneously with the decoloring process. The polarizing film can be cut by, for example, a cutting blade or laser light irradiation.

[Decolorization process]
In the decoloring step, a decoloring part is formed on a part of the polarizer stacked on the image display panel using a mark provided in the image display panel as an alignment reference. By using the mark provided in the image display panel as the alignment reference, the decolorization part can be formed with higher positional accuracy than when a part of the polarizer (or polarizing film) is used as the alignment reference.

  The decoloring part is preferably formed by irradiating a polarizer laminated on the image display panel with laser light from the polarizer side. According to laser light irradiation, a decoloring part having a desired shape can be formed satisfactorily. Moreover, even if it is a case where it has irradiated to the polarizer laminated | stacked in the state of the polarizing film (namely, when irradiated through a protective film), a decoloring part can be formed favorably. Furthermore, it can be excellent in mass productivity.

  The laser beam preferably includes light having a wavelength of at least 1500 nm. With a laser beam including such a wavelength, a decoloring part can be formed. More preferably, it contains light with a wavelength of at least 1000 nm or less, more preferably contains light with a wavelength of 200 nm to 800 nm, and particularly preferably contains light with a wavelength of 200 nm to 600 nm. According to the laser light including such a wavelength, the decoloring part can be formed while achieving surface uniformity. Specifically, the decoloring part can be formed without damaging (for example, thermal deformation) the polarizer peripheral optical member (for example, the protective film). Note that the damage to the polarizer peripheral optical member is considered to be one of the factors because the difference in absorbance between the polarizer and the peripheral optical member becomes large. Moreover, a decoloring part can be favorably formed without damaging the resin film itself. As a result, the flatness of the obtained image display device (image display panel) can be ensured, and a good module design can be achieved. Furthermore, according to the laser beam containing the said wavelength, the transmittance | permeability of the below-mentioned decoloring part can be achieved favorably.

  Examples of the laser include solid lasers such as YAG laser, YLF laser, YVO4 laser, and titanium sapphire laser, gas lasers including argon ion laser and krypton ion laser, fiber lasers, semiconductor lasers, and dye lasers. Preferably, a solid laser is used.

  As the laser, a short pulse laser (a laser that emits light having a pulse width of 1 nanosecond or less, such as a picosecond laser or a femtosecond laser) is preferably used. In order to suppress thermal damage to the resin film, a pulse width of 500 picoseconds or less (for example, 10 picoseconds to 50 picoseconds) is particularly preferable. By suppressing the thermal damage, it is possible to satisfactorily suppress the melting of the resin (for example, PVA resin) constituting the resin film. Therefore, a decoloring part having no unevenness and extremely excellent uniformity can be obtained, and as a result, distortion of the image of the camera can be prevented. In one embodiment, irradiation with laser light having different wavelengths and / or pulse widths may be combined. The type of laser light to be irradiated and the irradiation order can be appropriately set according to the purpose. For example, by irradiating with a picosecond laser and then with a nanosecond laser, both hue and transparency can be improved as compared with the case of irradiating with a picosecond laser alone. In this case, the nanosecond laser preferably has a shorter wavelength (for example, 400 nm to 460 nm) than the picosecond laser.

  The irradiation condition of the laser beam can be set to any appropriate condition. For example, when a solid laser (YVO4 laser) is used, the pulse energy is preferably 10 μJ to 150 μJ, more preferably 25 μJ to 71 μJ. The scanning speed is preferably 10 mm / second to 10000 mm / second, and more preferably 100 mm / second to 1000 mm / second. The repetition frequency can be appropriately set according to the set scanning speed and pulse energy so as to realize an optimum bleaching state. The repetition frequency is, for example, 100 Hz to 12480 Hz. The scan pitch is preferably 10 μm to 50 μm. The beam shape at the irradiation position of the laser beam can be appropriately set according to the purpose and the desired shape of the decoloring part. The beam shape may be, for example, a circle or a line. Any appropriate means can be adopted as means for setting the beam shape to a predetermined shape. For example, laser irradiation may be performed through a mask having a predetermined opening, or beam shaping may be performed using a diffractive optical element or the like. For example, when the beam shape is circular, the focal diameter (spot diameter) is preferably 50 μm to 60 μm. According to the above conditions, a decoloring part can be formed satisfactorily without damaging the polarizing film peripheral member and the resin film itself. Moreover, the optical characteristic of the decoloring part mentioned later can be achieved favorably.

  In addition, the said decoloring part can be formed favorably, achieving surface uniformity also by irradiating X-rays. In addition to this, for example, the decoloring portion can also be formed by a light source (for example, a Xe lamp) that emits light having a wavelength of 100 pm to 1500 nm, a heating means such as a heating plate for barcode printing, or the like.

  When irradiating the laser beam or the like, an irradiation position (that is, a decolored portion forming position) is determined using a mark included in the image display panel as an alignment reference. The irradiation position can be determined using, for example, a galvano scanner or a resonant scanner on the basis of the coordinate position of the read image by reading a mark such as an alignment mark with a transmission camera or the like. A representative example of the procedure for determining the irradiation position will be briefly described. One example uses the corners (typically, the upper two corners) of the boundary between the display part of the image display panel and the black matrix. More specifically, it is as follows: A transparent camera is scanned in the horizontal direction (left-right direction) and the vertical direction (up-down direction) of the panel to detect a portion with a large brightness change. The number of parts to be detected can be set appropriately. For example, it can be detected at about 100 points in each of the horizontal direction and the vertical direction. A tangent line is calculated from the portion thus detected, and an imaginary line (straight line) of the edge line is drawn. The intersection of the horizontal virtual line and the vertical virtual line is recognized as a corner, and the coordinates of each corner in the image display panel (corresponding to the panel origin in FIG. 2) are calculated. Here, if the positioning procedure is as described above, as shown in FIG. 2, even if the image display panel on which the polarizer is laminated is transported or arranged out of the reference position, the irradiation position is set. Can be determined accurately. That is, even when the reference position is deviated, the deviation angle θ can be calculated for the panel origin obtained by the above procedure. The camera origin (coordinates) and the processing origin (coordinates) are determined in advance on the production line (manufacturing apparatus), and their positional relationship does not change. Further, as shown in FIG. 2, the coordinates (X, Y) of the irradiation position are calculated from the panel origin by X = A1 cos (θ + θ ′) and Y = A1 cos (θ + θ ′). Since the positional relationship (deviation) between the camera origin and the panel origin can be calculated within the camera, the irradiation position can be determined based on the invariable processing origin and camera origin. As a result, the irradiation position can be determined very accurately. Another example uses the alignment mark of the image display panel. More specifically, it is as follows: Alignment marks (usually provided at two locations as shown in FIG. 1A) are registered in the camera in advance. The same mark as the registered mark is detected by the camera, and the coordinates of the mark in the camera field of view are calculated. By connecting the two marks with a line, the coordinates of the respective alignment marks on the image display panel are calculated. The subsequent procedure is the same as that in the case of using the corner portion of the boundary portion of the black matrix (FIG. 2), and as a result, the irradiation position can be determined very accurately.

  The transmittance of the decolorized part formed as described above (for example, the transmittance measured with light having a wavelength of 550 nm at 23 ° C.) is preferably 46% or more, more preferably 60% or more, and further preferably 75% or more. Particularly preferably, it is 90% or more.

Birefringence _{R PVA} bleaching unit is 0.035 or less, preferably 0.032 or less, more preferably 0.030 or less. The lower limit of the birefringence _{R PVA} bleaching unit is, for example, 0.010. With such a range birefringence R _PVA bleaching unit, not only to impart the desired transparency bleaching unit, in the case of using a bleaching unit as a camera hole portion of the image display device, brightness and color From both viewpoints, it is possible to achieve very good shooting performance. It is presumed that such birefringence can be realized when a complex of a resin (for example, a polyvinyl alcohol-based resin) that constitutes a resin film and iodine in the decolorization part is destroyed at an appropriate ratio. Such birefringence can be realized by using the above laser light and performing irradiation under the above conditions. In addition, birefringence _RPVA is calculated | required by a formula: _RPVA = nx-ny. Here, nx is the refractive index in the direction in which the refractive index in the film plane is maximum (that is, the slow axis direction), and ny is the direction that is orthogonal to the slow axis in the film plane (that is, the fast axis direction). ).

  The decolorization part has an absorbance at a wavelength of 350 nm of preferably 2.5 or less, more preferably 2.3 or less, and even more preferably 2.1 or less. The lower limit of the absorbance is 1.2, for example. When the decoloring part has such absorbance, when the decoloring part is used as the camera hole part of the image display device, it is possible to realize a very excellent photographing performance from the viewpoint of both brightness and color. This effect can be exhibited synergistically with the above-described effect due to birefringence. In the decolorization part, as described above, it is estimated that such an effect is realized by the decomposition of the complex of the PVA resin and iodine at an appropriate ratio. Furthermore, the iodine complex is also in an appropriate ratio. The above-mentioned desired absorbance can be realized by collapsing with, and a synergistic effect can be exhibited. Such absorbance can be realized by irradiating under the conditions as described above using the laser light as described above.

  The arrangement, shape, size, etc. of the decoloring part can be designed as appropriate. Preferably, it is designed according to the position, shape, size, etc. of the camera hole part of the image display device to be manufactured. Specifically, it is designed so that the decoloring part does not correspond to the display screen of the manufactured image display device.

  In the manufacturing method of the present invention, the decoloring part may be formed only on one of the polarizers laminated on both sides of the image display panel, or the decoloring part may be formed on both. For example, from the viewpoint of spatial restrictions, designability, and the like, there is a case where a backlight-side polarizer is not disposed at a position corresponding to the camera hole portion, particularly in a small image display device. In such a case, a decoloring part should just be formed only in the polarizer by the side of visual recognition, and a decoloring process can be performed only with respect to the polarizer (polarizing film) laminated | stacked by the visual recognition side. On the other hand, when forming a decoloring part in both polarizers, the said decoloring process is performed with respect to each of the polarizer (polarizing film) laminated | stacked on the both sides of the image display panel. In this case, the order of each process may be [a lamination process on one side / a decoloring process on one side / a laminating process on the other side / a decoloring process on the other side]. Lamination process / decolorization process on one side / decolorization process on the other side].

[Other processes]
Preferably, the method for manufacturing an image display device of the present invention includes a step of dividing the large-sized image display panel into a predetermined size (hereinafter sometimes referred to as “division step”) before the step of laminating. . A large image display panel (a so-called mother substrate) has a plurality of image display panels arranged, and a plurality of image display panels can be obtained by dividing.

  Examples of the dividing method include a scribing method in which a mother substrate is irradiated with laser light to form a scribe line. In the scribing method, for example, an alignment mark provided on the mother substrate is read by a camera or the like, and the cutting is performed at a scribing position determined based on the position.

  Preferably, in the method for manufacturing an image display device of the present invention, a step of mounting an electronic circuit for driving the image display panel after the step of forming the decoloring portion (hereinafter, referred to as a “mounting step”). Included). Examples of the mounting method of the driving electronic circuit include a TAB (Tape Automated Bonding) method, a COG (Chip on Glass) method, and the like.

  Therefore, in one preferable embodiment, the manufacturing method of the present invention includes a dividing step, a laminating step, a decoloring step, and a mounting step.

  After the mounting process, connection of a printed circuit board using a flexible printed board, assembly of a backlight component, etc., and then a lighting inspection or the like can be performed as appropriate.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples.

[Measurement of transmittance (Ts)]
Measurement was performed using a microspectroscopic system (Lambda Vision Co., Ltd., LVmicro). Note that Ts is a Y value measured by a two-degree field of view (C light source) of JIS Z8701 and corrected for visibility.
[Measurement of misalignment]
Measure the outer shape and center of the part corresponding to the camera hole part of the mounted image display device and the outer shape and center of the decoloring part actually formed, and the distance between the gaps and the center value of each outer shape Were compared to detect misalignment.

[Example 1]
<Image display panel>
A liquid crystal panel (194 mm long × 344 mm wide) was taken out from a commercially available notebook computer (product number VPCEB48FJ, manufactured by Sony Corporation), the polarizing plate attached to both sides thereof was removed, and the substrate surface was washed.

<Polarized film>
Commercially available polarizing film with pressure-sensitive adhesive layer (manufactured by Nitto Denko Corporation, product number “PFILV”, configuration: release liner / acrylic pressure-sensitive adhesive layer (20 μm) / second protective film (40 μm) / polarizer (25 μm) / number No. 1 protective film (40 μm) was punched into a shape corresponding to the shape of the liquid crystal panel.

<Lamination process and decolorization process>
The release liner was peeled from the polarizing film and attached to both sides of the liquid crystal panel via an adhesive layer. Next, the alignment marks printed on the upper corners of the glass substrate constituting the liquid crystal panel are read by the camera, and the irradiation position (that is, the note) on the viewing-side polarizing film (polarizer) with reference to those positions. The part corresponding to the camera hole part of the personal computer) was determined using a galvano scanner (product number “Nmark CLS” manufactured by Aerotech Co., Ltd.). Next, using a solid laser (wavelength: 532 nm), the viewing-side polarizing film (polarizer) was irradiated with laser light from the first protective film side. The irradiation conditions were a pulse energy of 40 μJ, a scanning speed of 100 mm / sec, and a repetition frequency of 6240 Hz. In this way, a circular decoloring part having a diameter of 3 mm was formed on the polarizing film (polarizer) laminated on the viewing side of the image display panel.

  The irradiated polarizing film (polarizer) is decolorized only in the area irradiated with the laser beam, the transmittance of the unirradiated portion is 44.0%, and the transmittance of the irradiated portion is 66.2%. It was. Further, the decoloring part was formed with high positional accuracy in a part corresponding to the camera hole part of the mobile phone, and the deviation between the position of the decoloring part and the part corresponding to the camera hole part was less than 20 μm.

[Example 2]
Polarized light laminated on the viewing side of the image display panel in the same manner as in Example 1 except that the boundary portion between the display portion provided on the color filter substrate of the liquid crystal panel and the black matrix of the outer frame was used as the alignment reference. A circular decolorization part having a diameter of 3 mm was formed on the film (polarizer).

  The irradiated polarizing film (polarizer) was decolorized only in the area irradiated with the laser beam, and the transmittance of the unirradiated portion and the transmittance of the irradiated portion were the same values as in Example 1. Further, the decoloring part was formed with high positional accuracy in a part corresponding to the camera hole part of the mobile phone, and the deviation between the position of the decoloring part and the part corresponding to the camera hole part was less than 20 μm.

[Comparative Example 1]
The polarizing film (polarizer) laminated on the viewing side of the image display panel is 3 mm in diameter in the same manner as in Example 1 except that both corners formed by the upper side and both sides of the polarizer are used as the alignment reference. A circular decolorization part was formed.

  The irradiated polarizing film (polarizer) was decolorized only in the area irradiated with the laser beam, and the transmittance of the unirradiated portion and the transmittance of the irradiated portion were the same values as in Example 1. The position of the formed decoloring part was shifted by 500 μm from the part corresponding to the camera hole part of the mobile phone.

[Comparative Example 2]
<Image display panel>
A liquid crystal panel similar to that used in Example 1 was used.

<Polarized film>
Two commercially available polarizing films with a pressure-sensitive adhesive layer as in Example 1 were punched into a shape corresponding to the shape of the liquid crystal panel. The irradiation position (that is, the part corresponding to the camera hole part of the mobile phone) is determined with respect to one of the punched polarizing films using the two corners formed by the upper side and both sides as an alignment reference, and the first protective film Laser light was irradiated from the side. Irradiation conditions were the same as in Example 1. The polarized film (polarizer) after irradiation was decolored only in the area irradiated with the laser beam, and a circular decoloring part having a diameter of 3 mm was formed. The transmittance of the unirradiated portion and the transmittance of the irradiated portion were the same values as in Example 1.

<Lamination process>
The release liner was peeled off from the polarizing film on which the decoloring part was formed, and was attached to the viewing side of the liquid crystal panel via an adhesive layer in the same manner as in Example 1. Moreover, the polarizing film which does not have a decoloring part was affixed on the backlight side similarly. The position of the decoloring part of the polarizing film (polarizer) after pasting was shifted by 500 μm from the part corresponding to the camera hole part of the mobile phone.

  The polarizer of the present invention is suitably used for an image display device with a camera (liquid crystal display device, organic EL device) such as a mobile phone such as a smartphone, a notebook PC, or a tablet PC.

DESCRIPTION OF SYMBOLS 10 Image display panel 11 Board | substrate 12 Color filter board | substrate 20 Alignment mark 21 Glass substrate 22 Display part 23 Black matrix

Claims (8)

A step of laminating a polarizer composed of a resin film containing a dichroic substance on at least one side of an image display panel having a mark recognizable from the outside, and the image display on a part of the laminated polarizer Forming a decoloring part using a mark provided on the panel as an alignment reference;
A method for manufacturing an image display device.   The method for manufacturing an image display device according to claim 1, wherein the decoloring portion corresponds to a camera hole portion of the image display device to be manufactured.   The method for manufacturing an image display device according to claim 1, wherein the decoloring portion is formed by laser light irradiation.   The method for manufacturing an image display device according to claim 3, wherein the laser light includes light having a wavelength of at least 1500 nm.   The method for manufacturing an image display device according to claim 3, wherein the laser is a solid-state laser.   The method for manufacturing an image display device according to claim 1, wherein the polarizer is laminated on one side or both sides of the image display panel in a state where a protective film is laminated on at least one side thereof.   The manufacturing method of the image display apparatus in any one of Claim 1 to 6 including the process of dividing | segmenting a large-sized image display panel into predetermined size before the said process to laminate | stack. The method for manufacturing an image display device according to claim 1, further comprising a step of attaching an electronic circuit for driving the image display panel to the image display panel after the step of forming the decoloring portion.