JP6704230B2 - Inspection method for long polarizer, inspection system, and manufacturing method - Google Patents

Description

The present invention relates to an inspection method for an elongated polarizer, an inspection system, and a manufacturing method. More specifically, the present invention relates to an inspection method, an inspection system, and a manufacturing method for an elongated polarizer having a non-polarization part.

Some image display devices such as mobile phones and notebook personal computers (PCs) are equipped with internal electronic components such as cameras. Various studies have been made for the purpose of improving the camera performance and the like of such image display devices (for example, Patent Documents 1 to 7). However, due to the rapid spread of smartphones and touch panel type information processing devices, further improvements in camera performance and the like are desired. Further, in order to cope with the diversification of the shape of the image display device and the enhancement of its function, a polarizing plate having a partial polarization performance is required. In order to realize these demands industrially and commercially, it is desired to manufacture an image display device and/or its components at an acceptable cost, and various studies are needed to establish such a technique. Matters are left.

JP, 2011-81315, A JP, 2007-241314, A US Patent Application Publication No. 2004/0212555 Korean Published Patent No. 10-2012-0118205 Korean Patent No. 10-1293210 JP2012-137738A U.S. Patent Application Publication No. 2014/0118826

The present invention has been made to solve the above-mentioned problems, and its main purpose is to realize a multifunctional and highly functionalized electronic device, and to manufacture a polarizer having no variation in quality. An object of the present invention is to provide an inspection method capable of inspecting this polarizer at high speed and efficiently.

The method for inspecting a long-sized polarizer of the present invention is a step of conveying a long-sized polarizer having non-polarizing portions arranged at least at predetermined intervals in the long-length direction, in the lengthwise direction, It includes a step of inspecting quality and a step of adjusting the transport distance according to the inspection time of the polarizer.
In one embodiment, the non-polarized portion is inspected for defects.
In one embodiment, the inspection is performed by imaging the polarizer.
In one embodiment, the above-mentioned light polarizer has a non-polarization part arranged at a predetermined interval in the length direction and the width direction.
According to another aspect of the present invention, a method for manufacturing an elongated polarizer is provided. This manufacturing method includes a step of forming a non-polarization part on a long-sized polarizer and a step of inspecting by the above-mentioned inspection method.
In one embodiment, the above-mentioned inspection is continuously performed after forming the above-mentioned non-polarization part.
In one embodiment, a basic solution is brought into contact with the polarizer to form the non-polarizing section.
In one embodiment, the basic solution is contacted with the polarizer protected by a protective material so that at least a part of the polarizer is exposed.
According to still another aspect of the present invention, an inspection system for an elongated polarizer is provided. This inspection system is provided at least on a transport line for transporting a long-sized polarizer having non-polarizing portions arranged at a predetermined interval in the long-length direction in the long-length direction, and provided on the above-mentioned transport line. And an accumulation device that is provided on the transfer line and that secures the inspection time by adjusting the distance of the transfer line.
In one embodiment, the inspection device inspects the non-polarized portion for defects.
In one embodiment, the inspection device includes a photographing device that photographs the polarizer.

ADVANTAGE OF THE INVENTION According to this invention, at the time of inspecting a predetermined site|part, conveying the elongate polarizer which has a non-polarization part, at least the flow of an inspection site|part can be decelerated or stopped. As a result, for example, inspection at higher speed and higher accuracy becomes possible.

3 is a schematic diagram illustrating an inspection method according to one embodiment of the present invention. FIG. It is a schematic plan view explaining an example of the arrangement pattern of the non-polarization part of the polarizer used for the inspection method of this invention. It is a schematic plan view explaining another example of the arrangement pattern of the non-polarization part of the polarizer used for the inspection method of this invention. It is a schematic plan view explaining another example of the arrangement pattern of the non-polarization part of the polarizer provided for the inspection method of this invention. (A) And (b) is a partial expanded view explaining the inspection method by one Embodiment of this invention. It is a figure explaining the inspection method of the polarizer by one embodiment of the present invention. It is a schematic perspective view explaining the bonding of the polarizer and the surface protection film according to one embodiment of the present invention. FIG. 3 is a partial cross-sectional view of a polarizing film laminate according to one embodiment of the present invention. 1 is a schematic perspective view of a polarizing plate according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

A. Inspection Method FIG. 1 is a schematic diagram illustrating an inspection method for an elongated polarizer according to one embodiment of the present invention. As shown in FIG. 1, the polarizer 100 is unrolled from the unrolling roll R1, transported by the transport rolls 30 to 42, and wound by the winding roll R2.

The transport line L is provided with an inspection device 10 for inspecting a polarizer. The inspection device 10 includes, for example, a photographing device that photographs the polarizer. In the illustrated example, the accumulation device 20 is provided on the upstream side of the inspection device 10. When inspecting (photographing) the polarizer by the inspection device 10, the accumulation device 20 accumulates the polarizer conveyed from the upstream side, and the polarization on the downstream side is accumulated without interrupting the flow of the polarizer on the upstream side. Slow down or stop the flow of the child. The accumulator 20 includes a dancer roll 21 that is vertically movable while supporting a polarizer. The dancer roll 21 is arranged from an imaginary line position not shown in FIG. It is lowered by a motor (moving device) to adjust the transport distance. In this case, the line on the downstream side is decelerated or stopped as the dancer roll 21 descends.

Unlike the example shown in the figure, when an accumulator is provided on the downstream side of the inspection device, the dancer roll is raised in correspondence with the timing of inspecting (imaging) the polarizer to shorten the transport distance, and It slows or stops the flow of the polarizer upstream without interrupting the flow.

Different from the illustrated example, when accumulators are provided on both the upstream side and the downstream side of the inspection apparatus, the upstream accumulator accumulates the polarizer conveyed from the upstream side and the downstream accumulator is used. Thus, by releasing the already accumulated polarizer to the downstream side, the flow of the polarizer at the inspection site can be decelerated or stopped without stopping the flow of the polarizer on the upstream side and the downstream side.

The inspection target of the inspection method of the present invention is an elongated polarizer having a non-polarization part. In the present specification, “long shape” means an elongated shape having a length sufficiently longer than the width, and for example, an elongated shape having a length 10 times or more, preferably 20 times or more the width. Including.

The non-polarizing section may be arranged in any appropriate pattern depending on the purpose. For example, the elongated polarizer has at least non-polarizing portions arranged in the longitudinal direction at a predetermined interval, and preferably has non-polarizing portions arranged in the longitudinal direction and the width direction at a predetermined interval. As a specific example, the non-polarizing section may be formed by cutting the polarizer into a predetermined size (for example, cutting in a lengthwise direction and/or a width direction, punching) when the polarizer is attached to an image display device having a predetermined size. It may be arranged at a position corresponding to the camera unit of the image display device.

In one embodiment, the non-polarization parts are arranged at substantially equal intervals in both the longitudinal direction and the width direction. In addition, "substantially equal intervals in both the longitudinal direction and the width direction" means that the intervals in the longitudinal direction are equal, and the intervals in the width direction are equal. It is not necessary that the interval in the length direction and the interval in the width direction are equal. In another embodiment, the non-polarizing parts may be arranged at substantially equal intervals in the longitudinal direction and at different intervals in the width direction. When the non-polarizing parts are arranged at different intervals in the width direction, the intervals of the adjacent non-polarizing parts may be different, or only a part (the interval of the specific adjacent non-polarizing parts) may be different. ..

FIG. 2A is a schematic plan view for explaining an example of the arrangement pattern of the non-polarization part of the polarizer used in the inspection method of the present invention, and FIG. 2B describes another example of the arrangement pattern of the non-polarization part. FIG. 2C is a schematic plan view for explaining still another example of the arrangement pattern of the non-polarization part. In one embodiment, as shown in FIG. 2A, in the non-polarizing section 110, a straight line connecting adjacent non-polarizing sections in the longitudinal direction is substantially parallel to the longitudinal direction, and The straight line connecting the non-polarizing portions adjacent to each other in the direction is arranged so as to be substantially parallel to the width direction. The non-polarizing section may be arranged such that a straight line connecting the adjacent non-polarizing sections forms predetermined angles θ _w and θ _L with respect to the longitudinal direction and/or the width direction.

As the plan view shape of the non-polarizing portion, any suitable shape can be adopted depending on the purpose. For example, as the plan view shape of the non-polarizing section, any appropriate shape can be adopted as long as it does not adversely affect the camera performance of the image display device in which the polarizer is used. Although the non-polarizing portion in the illustrated example is circular, it may be formed in, for example, an elliptical shape, a square shape, a rectangular shape, or a rhombic shape.

The transmittance of the non-polarizing part (for example, the transmittance measured with light having a wavelength of 550 nm at 23° C.) is preferably 50% or more, more preferably 60% or more, further preferably 75% or more, It is particularly preferably 90% or more. With such a transmittance, it is possible to prevent adverse effects on the shooting performance of the camera, for example, when the polarizer is arranged so that the non-polarizing section corresponds to the camera section of the image display device.

The non-polarizer can be in any suitable form. In one embodiment, the unpolarized portion is a partially bleached bleached portion. The decolorized portion is formed by, for example, laser irradiation or chemical treatment. In another embodiment, the non-polarizer is a through hole. The through hole is formed by, for example, mechanical punching (for example, punching, engraving blade punching, plotter, water jet) or removal of a predetermined portion (for example, laser ablation or chemical melting).

FIG. 3 is a partially enlarged view illustrating a method for inspecting an elongated polarizer according to an embodiment of the present invention. In the illustrated example, while the polarizer 100 is being conveyed in the direction of the arrow, the non-polarizing portions 110, 110,... Which are arranged on one line a along the lengthwise direction are inspected.

As shown in FIG. 3A, the detection sensor 200 installed corresponding to the line a detects the non-polarization part 110 that has reached the detection range. In other words, the detection sensor 200 detects that the non-polarization part 110 has passed the predetermined position b in the predetermined longitudinal direction. Any appropriate sensor can be used as the detection sensor 200 as long as it can discriminate between the non-polarizing section 110 and the area other than the non-polarizing section 110. As the detection sensor 200, for example, a transmitted light detection sensor, a reflected light detection sensor, or the like is used.

Next, as shown in FIG. 3B, the detected non-polarizing portion 110 is photographed by the photographing camera 300 installed on the downstream side of the detection sensor 200. The timing at which the non-polarizing unit 110 starts shooting by the shooting camera 300 can be determined based on the detection information from the detection sensor 200. Any appropriate camera can be adopted as the photographing camera 300. For example, a camera that irradiates light from below the polarizer and shoots the transmitted light from above the polarizer, and a camera that irradiates light from above the polarizer and shoots the light reflected by the polarizer A camera or the like may be used.

In the illustrated example, the detection sensor and the photographing camera are installed above the polarizer, but they may be installed below the polarizer. Further, the detection sensor and the camera for photographing can be installed so as to be movable in the width direction according to the position of the non-polarizing portion to be inspected. Although not shown, an illumination device may be installed on the side of the polarizer on which the photographing camera is not installed.

A plurality of photographing cameras may be installed in the width direction depending on the arrangement pattern of the non-polarizing section, the performance of the photographing camera used (for example, visual field), and the like. In this case, as shown in FIG. 4, one shooting camera 300 may be operated corresponding to one detection sensor 200, or unlike the illustrated example, one detection sensor may be used for a plurality of shooting cameras. The camera may be activated. In the illustrated example, the non-polarizing portions 110, 110... Are formed at a predetermined interval on the line a along the longitudinal direction, and are also formed at a predetermined interval on the line b along the width direction. ing. Then, a pair of detection sensor 200 and photographing camera 300 installed corresponding to each line a is installed. In this way, if the number of detection sensors is the same as the number of photographing cameras, it is possible to flexibly deal with the arrangement pattern of all non-polarizing portions.

By detecting that the non-polarization part has passed a predetermined place by the detection sensor installed on the upstream side, and by performing imaging of the non-polarization part by the imaging camera installed on the downstream side based on this detection information, The non-polarized portion formed on the elongated polarizer can be in-line inspected. Incorporating such an inspection method into the manufacturing process enables early detection of defects on the upstream side in the transport direction, which can contribute to an improvement in yield.

The image of the imaging camera is image-processed by any appropriate method to inspect the non-polarized portion and its vicinity. As a specific example, the shape of the non-polarizing portion (roundness in the case of a circular shape), the light transmittance of the non-polarizing portion, the tint of the non-polarizing portion, the presence or absence of foreign matter or bubbles, and the like are inspected. According to the present invention, at the time of continuously inspecting the non-polarization part while conveying the elongated polarizer, at least the flow at the inspection site can be decelerated or stopped. As a result, for example, the shutter speed of the photographing camera used for the inspection can be slowed down, and the photographing in a dark place and the inspection with higher accuracy (for example, spectrum measurement) can be realized.

B. Method for producing long polarizer having non-polarizing portion The method for producing an elongated polarizer having a non-polarizing portion of the present invention is to form a non-polarizing portion on a long polarizer, and the above inspection. Inspecting the unpolarized portion by a method.

B-1. Polarizer The polarizer is typically composed of a resin film containing a dichroic material. Examples of the dichroic substance include iodine and organic dyes. These may be used alone or in combination of two or more. Iodine is preferably used.

Any appropriate resin can be used as the resin forming the resin film. Preferably, a polyvinyl alcohol resin is used. Examples of the polyvinyl alcohol-based resin include polyvinyl alcohol and ethylene-vinyl alcohol copolymer. Polyvinyl alcohol is obtained by saponifying polyvinyl acetate. The ethylene-vinyl alcohol copolymer is obtained by saponifying an ethylene-vinyl acetate copolymer.

The polarizer (excluding the non-polarizing part) preferably exhibits absorption dichroism at any wavelength of 380 nm to 780 nm. The single transmittance of the polarizer (excluding the non-polarizing portion) is preferably 39% or more, more preferably 39.5% or more, still more preferably 40% or more, and particularly preferably 40.5% or more. The theoretical upper limit of the single transmittance is 50%, and the practical upper limit is 46%. In addition, the single transmittance is a Y value measured by a 2 degree visual field (C light source) of JIS Z8701 and subjected to luminosity correction. You can The polarization degree (excluding the non-polarized portion) of the polarizer is preferably 99.9% or more, more preferably 99.93% or more, still more preferably 99.95% or more.

The thickness of the polarizer can be set to any appropriate value. The thickness is preferably 30 μm or less, more preferably 25 μm or less, further preferably 20 μm or less, and particularly preferably 10 μm or less. On the other hand, the thickness is preferably 0.5 μm or more, more preferably 1 μm or more.

The absorption axis of the polarizer can be set in any appropriate direction depending on the purpose. The direction of the absorption axis may be, for example, the lengthwise direction or the width direction. A polarizer having an absorption axis in the longitudinal direction has an advantage of being excellent in manufacturing efficiency, for example. A polarizer having an absorption axis in the width direction has an advantage that it can be laminated by roll-to-roll with a retardation film having a slow axis in the long direction. In one embodiment, the absorption axis is substantially parallel to the lengthwise direction or the widthwise direction, and both widthwise ends of the polarizer are slit in parallel to the lengthwise direction. According to such a configuration, it is possible to easily manufacture a plurality of polarizers that can be cut based on the edges of the polarizer, have a non-polarizing portion at a desired position, and have an absorption axis in an appropriate direction. You can The absorption axis of the polarizer may correspond to the stretching direction in the stretching process described below.

The polarizer is typically obtained by subjecting the above resin film to various treatments such as swelling treatment, stretching treatment, dyeing treatment with the above dichroic substance, crosslinking treatment, washing treatment, and drying treatment. When performing various treatments, the resin film may be a resin layer formed on a base material. The formation of the non-polarizing portion may be performed during the process of manufacturing the polarizer.

B-2. Formation of Non-Polarizing Portion Preferably, the non-polarizing portion is a decolorizing portion. According to such a configuration, compared with the case where the through hole is formed mechanically (for example, by a method of mechanically using an engraving blade punching, a plotter, a water jet, etc.), cracks and delaminations are formed. Quality problems such as (delamination) and squeeze out of glue are avoided. The decolorization part is preferably formed by bringing a basic solution into contact with a desired position of a polarizer (resin film containing a dichroic substance). The non-polarization part formed by such a method may be a low-concentration part having a lower dichroic substance content than other parts (non-contact part). The low-concentration part has a low content of the dichroic substance itself, so the transparency of the non-polarizing part is maintained better than when the decolorizing part is formed by decomposing the dichroic substance with laser light etc. To be done.

The content of the dichroic substance in the low concentration part is preferably 1.0% by weight or less, more preferably 0.5% by weight or less, and further preferably 0.2% by weight or less. The lower limit of the content of the dichroic substance in the low concentration part is usually below the detection limit value. The difference between the content of the dichroic substance in the other portion and the content of the dichroic substance in the low concentration part is preferably 0.5% by weight or more, more preferably 1% by weight or more. When iodine is used as the dichroic substance, the iodine content is obtained from an X-ray intensity measured by fluorescent X-ray analysis using a calibration curve prepared in advance using a standard sample.

Any appropriate compound can be used as the basic compound contained in the basic solution. Examples of the basic compound include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide, alkaline earth metal hydroxides such as calcium hydroxide, and inorganic alkali metal salts such as sodium carbonate. , Organic alkali metal salts such as sodium acetate, aqueous ammonia and the like. Among these, hydroxides of alkali metals and/or alkaline earth metals are preferably used, and more preferably sodium hydroxide, potassium hydroxide and lithium hydroxide are used. The dichroic substance can be efficiently ionized, and the decolorized portion can be formed more easily. These basic compounds may be used alone or in combination of two or more.

Water and alcohol are preferably used as the solvent of the basic solution. The concentration of the basic solution is, for example, 0.01N to 5N, preferably 0.05N to 3N, and more preferably 0.1N to 2.5N. The liquid temperature of the basic solution is, for example, 20°C to 50°C. The contact time of the basic solution can be set according to the thickness of the polarizer and the type and concentration of the basic compound contained in the basic solution. The contact time is, for example, 5 seconds to 30 minutes, preferably 5 seconds to 5 minutes.

Any appropriate method can be adopted as a method of contacting the basic solution. For example, a method of dropping, coating and spraying a basic solution on the polarizer, and a method of immersing the polarizer in the basic solution can be mentioned. Upon contact with the basic solution, the polarizer may be protected by any appropriate protective material so that the basic solution does not contact other than the desired site. As such a protective material, for example, a protective film or a surface protective film is used. The protective film can be used as it is as a protective film for a polarizer. The surface protection film is used temporarily during the production of the polarizer. Since the surface protective film is removed from the polarizer at any appropriate timing, it is typically attached to the polarizer via an adhesive layer. Another specific example of the protective material is a photoresist or the like. Further, the base material used in the above-mentioned polarizer manufacturing process can also be used as a protective material.

Preferably, the surface of the polarizer is covered with a surface protective film so that at least a part of the surface of the polarizer is exposed upon contact with the basic solution. The polarizer having the arrangement pattern of the non-polarizing part as in the illustrated example has a surface protection film in which a small circular through hole corresponding to a desired non-polarizing part size is formed at a position corresponding to the arrangement pattern. A polarizing film laminate is prepared by adhering the polarizing film laminate to one side of the above, and a basic solution is brought into contact with the laminate to produce a polarizing film. At that time, it is preferable that the other side of the polarizer (the side on which the surface protective film having the through holes is not arranged) is also protected. As shown in FIG. 5, it is preferable that the protective film and the surface protective film are bonded together by roll-to-roll. In the present specification, the term “roll to roll” refers to stacking the roll-shaped films while transporting the roll-shaped films so that their lengthwise directions are aligned.

FIG. 6 is a partial cross-sectional view of a polarizing film laminate according to one embodiment of the present invention. The polarizing film layered body 101 includes a polarizer 100, a first surface protection film 50 arranged on one surface side (upper surface side in the illustrated example) of the polarizer 100, and another surface side (lower surface in the illustrated example) of the polarizer 100. The protective film 60 and the second surface protective film 70 arranged on the side). The polarizing film laminate 101 has exposed portions 120, 120,... On which one side (the upper side in the illustrated example) of the polarizer 100 is exposed. The exposed portion 120 is provided by forming the through hole 51 in the first surface protection film 50.

Examples of the material for forming the surface protective film include ester-based resins such as polyethylene terephthalate-based resins, cycloolefin-based resins such as norbornene-based resins, olefin-based resins such as polyethylene and polypropylene, polyamide-based resins, polycarbonate-based resins, and combinations thereof. Examples thereof include polymer resins. Preferred are ester resins (particularly polyethylene terephthalate resins). This is because the elastic modulus is sufficiently high, and for example, deformation of the through holes does not easily occur even when tension is applied during transportation and/or bonding. The thickness of the surface protective film is typically 20 μm to 250 μm, preferably 30 μm to 150 μm.

The first surface protective film has through holes arranged in a predetermined pattern. The position of the through hole corresponds to the position where the non-polarization part is formed. The shape of the through hole corresponds to the shape of the desired non-polarizing portion. The through holes are formed by, for example, mechanical punching (for example, punching, engraving blade punching, plotter, water jet) or removal of a predetermined portion of the film (for example, laser ablation or chemical melting).

The surface protection film is peeled and removed at any appropriate timing after the contact with the basic solution, for example.

Examples of materials for forming the protective film include cellulosic 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 resin. Examples thereof include resins, polyamide-based resins, polycarbonate-based resins, and copolymer resins of these. The thickness of the protective film is preferably 10 μm to 100 μm.

A surface of the protective film on which the polarizer is not laminated may be subjected to a hard coat layer, an antireflection treatment, or a treatment for the purpose of diffusion or antiglare as a surface treatment layer. The protective film is typically attached to the polarizer via an adhesive layer.

In one embodiment, the basic solution is removed from the polarizer by any suitable means after contacting the polarizer. According to such an embodiment, for example, it is possible to more reliably prevent a decrease in the transmittance of the non-polarizing portion due to the use of the polarizer. Specific examples of the method for removing the basic solution include washing, wiping and removing with a waste cloth, suction removal, natural drying, heat drying, blow drying, reduced pressure drying and the like. Preferably the basic solution is washed. Examples of the cleaning liquid used for cleaning include water (pure water), alcohols such as methanol and ethanol, and mixed solvents thereof. Water is preferably used. The number of times of washing is not particularly limited and may be performed plural times. When the basic solution is removed by drying, the drying temperature is, for example, 20°C to 100°C.

Preferably, after the contact with the basic solution, the alkali metal and/or the alkaline earth metal contained in the resin film is reduced at the contact portion where the basic solution is contacted. By reducing the amount of alkali metal and/or alkaline earth metal, it is possible to obtain a non-polarizing portion having excellent dimensional stability. Specifically, even in a humid environment, the shape of the non-polarizing portion formed by contact with the basic solution can be maintained as it is.

By contacting with the basic solution, hydroxides of alkali metal and/or alkaline earth metal may remain at the contact portion. In addition, by contacting with a basic solution, a metal salt of an alkali metal and/or an alkaline earth metal (for example, borate) can be generated at the contact portion. These can generate hydroxide ions, and the generated hydroxide ions act (decompose/reduce) on the dichroic substance (for example, iodine complex) existing around the contact area to expand the non-polarization region. obtain. Therefore, it is considered that by reducing the amount of the alkali metal and/or the alkaline earth metal salt, it is possible to suppress the expansion of the non-polarization region over time and maintain the desired non-polarization portion shape.

The non-polarizing part has an alkali metal and/or alkaline earth metal content of preferably 3.6% by weight or less, more preferably 2.5% by weight or less, and further preferably 1.0% by weight. % Or less, particularly preferably 0.5% by weight or less. The content of the alkali metal and/or the alkaline earth metal can be determined, for example, from an X-ray intensity measured by fluorescent X-ray analysis using a calibration curve prepared in advance using a standard sample.

As a method for reducing the above, preferably used is a method of bringing an acidic solution into contact with the contact portion with the basic solution. According to such a method, the alkali metal and/or the alkaline earth metal can be efficiently transferred to the acidic solution, and the content thereof can be reduced. The contact with the acidic solution may be carried out after removing the basic solution or without removing the basic solution.

Any appropriate acidic compound can be used as the acidic compound contained in the acidic solution. Examples of the acidic compound include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and hydrogen fluoride, and organic acids such as formic acid, oxalic acid, citric acid, acetic acid and benzoic acid. Among these, the acidic compound contained in the acidic solution is preferably an inorganic acid, more preferably hydrochloric acid, sulfuric acid or nitric acid. These acidic compounds may be used alone or in combination of two or more.

Water and alcohol are preferably used as the solvent of the acidic solution. The concentration of the acidic solution is, for example, 0.01N to 5N, preferably 0.05N to 3N, and more preferably 0.1N to 2.5N. The liquid temperature of the acidic solution is, for example, 20°C to 50°C. The contact time of the acidic solution is, for example, 5 seconds to 5 minutes. The method of contacting the acidic solution may be the same as the method of contacting the basic solution. Also, the acidic solution can be removed from the polarizer. As the method for removing the acidic solution, the same method as the method for removing the basic solution can be adopted.

B-3. Inspection of Non-Polarizing Part After forming the non-polarizing part, the non-polarizing part is inspected by the above-mentioned inspection method. At the time of inspection, the surface protective film may be laminated on the polarizer, or the surface protective film may be peeled off. In addition, when performing the inspection, it is preferable that the polarizer is in a state of a polarizing plate with a protective film attached to at least one side.

In one embodiment, after forming the non-polarization part, the non-polarization part is continuously inspected. Specifically, after forming the non-polarizing portion, the non-polarizing portion is inspected without winding the polarizer once. For example, after forming a non-polarizing part on a polarizing film laminate as shown in FIG. 6, the film is subjected to an inspection step of the non-polarizing part as it is. In this way, by performing the inspection continuously after the formation of the non-polarization part (specifically, by determining whether the size of the formed non-polarization part is larger or smaller than a predetermined size), for example, It is possible to early detect defects in the contact step with the basic solution (for example, the state of through holes in the surface protection film, the immersion state of the basic solution). The accumulation device as shown in FIG. 1 can be installed at any appropriate position on the polarizer production line.

After inspection, the polarizer may practically be provided as a polarizing plate. In one embodiment, the polarizing plate has a pressure-sensitive adhesive layer for bonding to another member. Preferably, a separator is temporarily attached to the surface of this pressure-sensitive adhesive layer to protect the pressure-sensitive adhesive layer until actual use and to enable roll formation as shown in FIG.

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

L transport line 10 inspection device 20 accumulation device 100 polarizer 110 non-polarization part 200 detection sensor 300 camera for photography

Claims (8)

At least a long polarizer having a non-polarizing portion arranged at a predetermined interval in the long direction, in a conveying line, the step of conveying in the long direction, and
Including a step of inspecting the quality of the polarizer, including inspecting a defect of the non-polarization part by photographing the polarizer on the transport line , and
Adjusting the distance of the transport line, including slowing or stopping the flow of the polarizer at the inspection site,
Inspection method. The inspection method according to claim 1, wherein the polarizer has non-polarizing portions arranged at predetermined intervals in a lengthwise direction and a width direction. A step of forming a non-polarizing portion on a long polarizer, and
The manufacturing method of the elongate polarizer which has a non-polarization part including the process which inspects by the inspection method of Claim 1 or 2. The manufacturing method according to claim 3, wherein the inspection is continuously performed after the formation of the non-polarizing portion. The manufacturing method according to claim 3, wherein the non-polarizing part is formed by contacting a basic solution with a polarizer. The manufacturing method according to claim 5, wherein the polarizer is contacted with the basic solution while being protected by a protective material so that at least a part of the polarizer is exposed. At least a transport line for transporting the elongated polarizer having a non-polarizing portion arranged at a predetermined interval in the elongated direction in the elongated direction,
An inspection device which is provided in the transport line and inspects the defects of the non-polarizing portion to inspect the quality of the polarizer,
And an accumulator device provided on the transfer line to secure the inspection time by adjusting the distance of the transfer line. The inspection system according to claim 7, wherein the inspection device includes an image capturing device that captures an image of the polarizer.

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