WO2016208464A1 - Adhesive-film manufacturing method and polarizer manufacturing method - Google Patents

Abstract

Provided are a manufacturing method of an adhesive film that is suitably employed as a surface protection film when selectively processing a predetermined portion of a subject and a manufacturing method of a polarizer employing such an adhesive film. An adhesive-film manufacturing method according to the present invention includes: preparing a laminated body 10 that has a resin substrate 11, an adhesive-agent layer 12 provided on one side of the resin substrate 11, and a separator 13 that is temporarily attached to an adhesive surface of the adhesive-agent layer 12; and forming a through-hole that passes through the separator 13, the adhesive-agent layer 12, and the resin substrate 11 as a single unit by cutting the laminated body 10 from the separator 13 side.

Description

Method for producing adhesive film and method for producing polarizer

The present invention relates to a method for producing an adhesive film and a method for producing a polarizer. In more detail, this invention relates to the manufacturing method of the adhesive film which has a through-hole, and the manufacturing method of the polarizer which has a non-polarizing part using the said adhesive film.

Adhesive films are used in a wide range of applications because they are excellent in processability and can impart a wide variety of properties. For example, utilization as a surface protective film when a predetermined portion of an object is selectively processed is desired.

Incidentally, 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 an image display device (for example, Patent Documents 1 to 6). However, with 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 diversification and high functionality of the shape of the image display device, there is a demand for a polarizing plate partially having polarization performance.

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

The present invention has been made to solve the above-described conventional problems, and its main purpose is to be suitably used as a surface protective film when a predetermined portion of an object (for example, a polarizer) is selectively processed. It is in providing the adhesive film made. Another object of the present invention is to provide a polarizer capable of realizing multi-functionality and high functionality of an electronic device such as an image display device.

The method for producing an adhesive film of the present invention prepares a laminate having a resin substrate, an adhesive layer provided on one surface of the resin substrate, and a separator temporarily attached to the adhesive surface of the adhesive layer. And cutting from the separator side of the laminate to form a through-hole that integrally penetrates the separator, the pressure-sensitive adhesive layer, and the resin base material.
In one embodiment, the through hole is formed in a state in which a patch is applied to the resin base material side of the laminate.
In one embodiment, it cuts in the middle of the above-mentioned patch from the above-mentioned separator surface, and forms the above-mentioned penetration hole.
In one embodiment, the said contact material is bonded together by the adhesive to the said laminated body.
In one embodiment, the manufacturing method of the above-mentioned adhesive film further includes removing the above-mentioned patch from the above-mentioned layered product.
In one embodiment, the through hole is formed by cutting with a cutting blade.
In one embodiment, the through hole is formed by laser light irradiation.
According to another aspect of the present invention, a method for producing a film is provided. In this method, the pressure-sensitive adhesive film obtained by the above production method is bonded to a film, and a portion corresponding to the through hole of the film is selectively processed.
According to still another aspect of the present invention, a method for producing a polarizer is provided. The polarizer is manufactured by peeling the separator from the adhesive film obtained by the manufacturing method, and bonding the adhesive film from which the separator is peeled to a resin film containing a dichroic substance. Forming a non-polarizing portion in a portion corresponding to the through hole of the adhesive film.
In one embodiment, the pressure-sensitive adhesive film from which the separator is peeled has a resin base material and a pressure-sensitive adhesive layer provided on one surface of the resin base material. A through-hole penetrating integrally is formed, and the peripheral edge of the through-hole on the pressure-sensitive adhesive layer side is formed on an arc surface.
In one embodiment, the manufacturing method of the above-mentioned polarizer further includes peeling the above-mentioned adhesion film from the resin film containing the above-mentioned dichroic substance after forming the above-mentioned non-polarization part.
In one embodiment, the said non-polarizing part is formed by making a basic solution contact the resin film containing the said dichroic substance.
In one embodiment, the basic solution comprises an alkali metal and / or alkaline earth metal hydroxide.
In one embodiment, the manufacturing method of the said polarizer further includes reducing the alkali metal and / or alkaline-earth metal which are contained in the said resin film in a contact part with the said basic solution.
In one embodiment, the alkali metal and / or alkaline earth metal is reduced while the adhesive film is bonded to the resin film containing the dichroic substance.

According to one embodiment of the present invention, it is possible to provide an adhesive film that is suitably used as a surface protective film when a predetermined portion of an object (for example, a polarizer) is selectively processed. By using such an adhesive film, it is possible to satisfactorily form a non-polarizing part having a desired shape. The polarizer obtained by the present invention can realize multi-functionality and high functionality of electronic devices, and is suitably used for electronic devices. Further, the polarizer obtained by the present invention is not only a receiving electronic device such as an image or a monitor, but also a transmitting electronic device such as an LED light or an infrared sensor, and transparency to the naked eye and light straightness. Can be suitably used for an image display device that secures the image quality.

It is sectional drawing of the laminated body by one Embodiment of this invention. 1 is a plan view of a polarizer according to one embodiment of the present invention. FIG. It is sectional drawing of the polarizing film laminated body by one Embodiment of this invention. (A) is an observation photograph in the state where the pressure-sensitive adhesive film of the example is bonded to a polarizer, and (b) is an observation photograph in a state where the pressure-sensitive adhesive film of a comparative example is bonded to the polarizer.

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

The method for producing an adhesive film of the present invention prepares a laminate having a resin substrate, an adhesive layer provided on one surface of the resin substrate, and a separator temporarily attached to the adhesive surface of the adhesive layer. And forming a through hole in the laminate.

A. Laminate FIG. 1 is a cross-sectional view of a laminate according to one embodiment of the present invention. The laminate 10 includes a resin base material 11, a pressure-sensitive adhesive layer 12 provided on one surface of the resin base material 11, and a separator 13 temporarily attached to the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer 12. For example, the laminated body has a long shape. In the present specification, the “elongate shape” means an elongated shape having a sufficiently long length with respect to the width, for example, an elongated shape having a length of 10 times or more, preferably 20 times or more with respect to the width. Including. In this case, the laminate can be wound into a roll.

Resin base material can function as a base material for the resulting adhesive film. The resin base material is preferably a film having high hardness (for example, elastic modulus). This is because the deformation of the through hole can be prevented. Specifically, deformation of the through-hole can be prevented even when tension is applied when using the obtained adhesive film (for example, when transporting and / or bonding).

Examples of the resin base material include ester resins such as polyethylene terephthalate resins, cycloolefin resins such as norbornene resins, olefin resins such as polypropylene, polyamide resins, polycarbonate resins, and copolymer resins thereof. Etc. Preference is given to ester resins (especially polyethylene terephthalate resins). Such a material has an advantage that the elastic modulus is sufficiently high and deformation of the through hole is difficult to occur.

The thickness of the resin base material is typically 20 μm to 250 μm, preferably 30 μm to 150 μm. Such a thickness has the advantage that deformation of the through hole is difficult to occur.

The elastic modulus of the resin base material is preferably 2.2 kN / mm ² to 4.8 kN / mm ² . If the elastic modulus of the resin substrate is in such a range, there is an advantage that the deformation of the through hole is difficult to occur. The elastic modulus is measured according to JIS K 6781.

The tensile elongation of the resin base material is preferably 90% to 170%. If the tensile elongation of the resin substrate is in such a range, for example, there is an advantage that it is difficult to break during transportation. The tensile elongation is measured according to JIS K 6781.

The pressure-sensitive adhesive layer can be formed of any appropriate pressure-sensitive adhesive as long as the effects of the present invention are obtained. Examples of the base resin for the pressure-sensitive adhesive include acrylic resins, styrene resins, and silicone resins. From the viewpoints of chemical resistance of the resulting adhesive film, adhesion to the adherend (for example, adhesion to prevent the treatment liquid from entering during immersion), and the degree of freedom for the adherend, an acrylic resin Is preferred. Examples of the crosslinking agent that can be included in the pressure-sensitive adhesive include isocyanate compounds, epoxy compounds, and aziridine compounds. The pressure-sensitive adhesive may contain, for example, a silane coupling agent. The formulation of the pressure-sensitive adhesive can be appropriately set according to the purpose.

The pressure-sensitive adhesive layer can be formed by any appropriate method. Specific examples include a method of applying a pressure-sensitive adhesive solution on a resin substrate and drying, a method of previously laminating a pressure-sensitive adhesive layer previously formed on a separator, and the like. Examples of the coating method include roll coating methods such as reverse coating and gravure coating, spin coating methods, screen coating methods, fountain coating methods, dipping methods, and spray methods.

The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 60 μm, more preferably 3 μm to 30 μm. If the thickness is too thin, the adhesiveness becomes insufficient, and bubbles or the like may enter the adhesive interface. If the thickness is too thick, problems such as sticking out of the adhesive easily occur.

The separator can function as a protective material that protects the adhesive layer (adhesive film) until it is practically used. Moreover, an adhesive film can be favorably wound up in roll shape by using a separator. As the separator, for example, a plastic (for example, polyethylene terephthalate (PET), polyethylene, polypropylene) film, non-woven fabric or surface coated with a release agent such as a silicone release agent, a fluorine release agent, or a long-chain alkyl acrylate release agent For example, paper. The thickness of the separator can be set to any appropriate thickness depending on the purpose. The thickness of the separator is, for example, 10 μm to 100 μm.

The laminate can be produced by any appropriate method. Specifically, it may be produced by laminating a separator on an adhesive layer formed on a resin base material, or may be produced by laminating a resin base material on an adhesive layer formed on a separator. .

B. Formation of a through hole Next, a through hole is formed in the laminate. Specifically, the laminate is cut by any appropriate cutting method to form a through hole that integrally penetrates the resin base material, the pressure-sensitive adhesive layer, and the separator. Examples of the cutting method include a cutting blade (punching die) such as a Thomson blade and a pinnacle blade, a method of mechanically cutting using a water jet or the like, and a method of cutting by irradiating a laser beam.

For example, when a plurality of through holes are formed in the laminate, cutting with the above cutting blade can be suitably employed. Cutting with the cutting blade can be performed in any suitable manner. For example, it may be performed using a punching device in which a plurality of cutting blades are arranged in a predetermined pattern, or may be performed by moving the cutting blades using a device such as an XY plotter. Thus, since the cutting blade can be moved and cut so as to correspond to a predetermined position of the laminated body, a through-hole can be formed with high accuracy at a desired position of the laminated body. In one embodiment, cutting with a cutting blade can be performed in conjunction with the conveyance appropriately while roll conveying a long laminate. More specifically, the through hole can be formed at a desired position of the laminate by appropriately adjusting the cutting timing and / or the moving speed of the cutting blade in consideration of the conveyance speed of the laminate. The punching device may be a reciprocating method (flat driving) or a rotary method (rotating).

Any appropriate laser can be adopted as the laser as long as the laminate can be cut. Preferably, a laser capable of emitting light having a wavelength in the range of 193 nm to 10.6 μm is used. Specific examples include a gas laser such as a CO ₂ laser and an excimer laser; a solid laser such as a YAG laser; and a semiconductor laser. Preferably, a CO ₂ laser is used.

The irradiation condition of the laser beam can be set to any appropriate condition depending on, for example, the laser to be used. The output condition is, for example, 0.1 W to 250 W when a CO ₂ laser is used.

When cutting the laminate, it is preferable to apply a patch to one side of the laminate. Specifically, the contact material is applied to the surface of the laminate on the end side in the cutting direction. By using the pad, when the pad is peeled from the laminate after cutting, the perforated residue can be removed at the same time. Specifically, the contact material can be peeled from the laminated body with the perforated residue attached to the contact material. Moreover, the deformation | transformation of the laminated body by cutting | disconnection can be suppressed by using a patch. For example, when cutting with a cutting blade, deformation of the adhesive layer can be particularly suppressed.

In a preferred embodiment, the through hole is formed by cutting from the surface of the laminate to the middle of the pad. According to such a form, the through-hole which penetrates the said resin base material, an adhesive layer, and a separator integrally can be formed favorably. Moreover, when peeling off a patch from a laminated body, perforated debris can be removed favorably.

As the above-mentioned adhesive material, a polymer film is preferably used. As the polymer film, a film similar to the resin substrate can be used. Furthermore, a soft (eg, low elastic modulus) film such as a polyolefin (eg, polyethylene) film can also be used. In one embodiment, a film having high hardness (for example, elastic modulus) is preferably used as the polymer film. This is because deformation of the laminate due to cutting can be satisfactorily suppressed. The thickness of the polymer film is preferably 20 μm to 100 μm.

Preferably, the patch is bonded to the laminate with an adhesive. By sticking the backing material to the laminate, it is possible to prevent problems such as shifting of the backing material during cutting. Moreover, when peeling off a patch from a laminated body, perforated debris can be removed favorably. Any appropriate pressure-sensitive adhesive can be used as the pressure-sensitive adhesive to which the patch is bonded, as long as it has an adhesive force capable of peeling the patch from the laminate after cutting. In one embodiment, the adhesive layer is previously formed in the patch. The thickness of the pressure-sensitive adhesive layer formed on the patch is preferably 1 μm to 50 μm.

In one embodiment, it is preferable that the shape of the pad material corresponds to the shape of the laminated body. For example, when the laminated body is long, a long patch is used. According to such a shape, perforated debris can be satisfactorily removed when the patch is peeled from the laminate. Further, when a plurality of through-holes are formed in the laminate, perforated debris can be removed continuously, and productivity can be significantly improved.

When forming the through hole, cut from the separator side of the laminate. By cutting from the separator side, the influence on the bonding of the adhesive film obtained by cutting can be suppressed. Specifically, when cutting with a cutting blade, the adhesive layer of the laminate can be deformed following the cutting blade. When cut from the resin substrate side, the pressure-sensitive adhesive layer swells on the pressure-sensitive adhesive surface side of the resulting pressure-sensitive adhesive film, and a bulge is formed on the periphery of the through hole. As a result, when the obtained adhesive film is bonded to the adherend, bubbles can be generated around the through holes. On the other hand, when cut from the separator side, the pressure-sensitive adhesive layer can be deformed following the cutting blade, but the peripheral edge on the pressure-sensitive adhesive side of the through-hole of the pressure-sensitive adhesive film is smooth (for example, an arc surface) Even if they are attached to the body, the generation of bubbles can be prevented. In addition, by cutting from the separator side, when the pad is used, the perforated debris can be removed well when the pad is peeled from the laminate after cutting.

Any appropriate shape can be adopted as the plan view shape of the through hole depending on the purpose. Specific examples include a circle, an ellipse, a square, a rectangle, and a rhombus. In one embodiment, the shape of the through hole in plan view has a shape corresponding to the shape of a desired non-polarizing part in the manufacture of the polarizer described later. Specifically, when the illustrated polarizer (described later) is produced, the plan view shape of the through hole is a small circle. By appropriately configuring the through hole forming means, a through hole having a desired planar view shape can be formed. When a device such as a punching device or an XY plotter is used, a through hole having a shape in plan view corresponding to the shape of the cutting blade (punching die) can be formed.

C. Use example The adhesive film of this invention is used suitably as a surface protection film at the time of selectively processing the predetermined | prescribed part of a target object (typically a film), for example. Examples of the selective treatment include decolorization, coloring, perforation, development, etching, patterning (for example, formation of an active energy ray-curable resin layer), chemical modification, and heat treatment. Hereinafter, the manufacturing method of the polarizer which has a non-polarizing part is demonstrated as a specific example.

C-1. Polarizer FIG. 2 is a plan view of a polarizer according to one embodiment of the invention. The polarizer 1 is composed of a resin film containing a dichroic substance. The polarizer (resin film) 1 has a non-polarizing part 2. The non-polarizing part 2 is preferably a low-concentration part in which the content of the dichroic substance is lower than that of the other part 3. According to such a configuration, cracks and delamination are mechanically compared (for example, by a method of mechanical engraving using a sculpture blade punching, a plotter, a water jet, or the like), compared to a case where a through hole is formed. Quality problems such as (delamination) and paste sticking are avoided. In addition, since the content of the dichroic substance itself is low in the low-concentration part, the transparency of the non-polarizing part is higher than when the non-polarizing part is formed by decomposing the dichroic substance with laser light or the like. Maintained well.

In the illustrated example, the small circular non-polarizing part 2 is formed at the center of the upper end of the polarizer 1, but the number, arrangement, shape, size, etc. of the non-polarizing part can be appropriately designed. For example, it is designed according to the position, shape, size, etc. of the camera unit of the mounted image display device. Specifically, the non-polarizing part is designed not to correspond to a part (for example, an image display part) other than the camera of the image display apparatus.

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, still more preferably 75% or more, and particularly preferably 90% or more. It is. With such transmittance, desired transparency can be ensured. For example, when the non-polarizing part is associated with the camera part of the image display device, it is possible to prevent an adverse effect on the photographing performance of the camera.

The polarizer (excluding the non-polarized part) preferably exhibits absorption dichroism in the wavelength range of 380 nm to 780 nm. The single transmittance (Ts) of the polarizer (excluding the non-polarized part) 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%. Further, the single transmittance (Ts) is a Y value measured by a JIS Z8701 two-degree field of view (C light source) and corrected for visibility, for example, using a microspectroscopic system (Lambda Vision, LVmicro). Can be measured. The degree of polarization of the polarizer (excluding the non-polarizing part) is preferably 99.8% or more, more preferably 99.9% or more, and further preferably 99.95% or more.

The thickness of the polarizer (resin film) can be set to any appropriate value. The thickness is typically 0.5 μm or more and 80 μm or less. The thickness of the polarizer is preferably 30 μm or less, more preferably 25 μm or less, further preferably 18 μm or less, particularly preferably 12 μm or less, and most preferably less than 8 μm. On the other hand, the thickness is preferably 1 μm or more. The lower the thickness, the better the low concentration part can be formed. Specifically, the low-concentration part can be formed in a shorter time in contact with the decoloring liquid described later. Moreover, the thickness of the part which contacted the decoloring liquid may become thinner than another part. When the thickness is small, the difference in thickness between the contact portion with the decoloring liquid and other portions can be reduced, and bonding with other components such as a protective film can be performed satisfactorily.

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. This is because the low-concentration portion can be favorably formed by contact with a basic solution described later.

The low concentration portion is a portion where the content of the dichroic substance is lower than that of the other portion. 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 still more preferably 0.2% by weight or less. If the content of the dichroic substance in the low concentration part is within such a range, the desired transparency can be sufficiently imparted to the low concentration part. For example, when a low-density part is associated with the camera part of the image display device, it is possible to realize extremely excellent photographing performance from the viewpoints of both brightness and color. On the other hand, the lower limit value of the content of the dichroic substance in the low concentration part is usually not more than the detection limit value. When iodine is used as the dichroic substance, the iodine content is obtained from a calibration curve prepared in advance using a standard sample, for example, from the X-ray intensity measured by fluorescent X-ray analysis.

The difference between the content of the dichroic substance in the other part 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.

Any appropriate resin can be used as the resin 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. The 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 degree of saponification 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 average degree of polymerization of the PVA resin can be appropriately selected according to the purpose. The average degree of polymerization is usually 1000 to 10,000, preferably 1200 to 4500, and more preferably 1500 to 4300. The average degree of polymerization can be determined according to JIS K 6726-1994.

C-2. Manufacturing method of polarizer The polarizer corresponds to a through-hole of the adhesive film of the resin film by bonding the adhesive film with the separator peeled to the resin film containing the dichroic material to obtain a polarizing film laminate. Forming a non-polarizing part in the part to be performed.

C-2-1. Polarizing film laminate A separator is peeled from an adhesive film obtained by forming through-holes in the laminate, and the adhesive film is bonded to a resin film containing a dichroic substance to obtain a polarizing film laminate. FIG. 3 is a cross-sectional view of a polarizing film laminate according to one embodiment of the present invention. The polarizing film laminate 100 includes a resin film (polarizer) 20 containing a dichroic substance, an adhesive film 10a disposed on one surface side (the upper surface side in the illustrated example) of the resin film 20, and the other surface of the resin film 20. The protective film 30 and the surface protective film 40 are disposed on the side (the lower surface side in the illustrated example). The adhesive film 10 a is bonded to the resin film 20 by the adhesive layer 12. The through-hole 14 formed in the adhesive film 10a has an exposed portion 21 in which the resin film 20 is exposed on one surface side (upper surface side in the illustrated example) of the polarizing film laminate 100.

It is preferable that the shape of the adhesive film 10a corresponds to the shape of the resin film 20 to be bonded. For example, when the resin film 20 is long, the adhesive film 10a is long. In this case, the lamination of the resin film and the adhesive film is preferably performed by roll-to-roll. “Roll-to-roll” refers to laminating a roll film while aligning each other in the longitudinal direction. The width of the long adhesive film 10a may be designed to be substantially the same as or larger than the width of the resin film 20.

When laminating a resin film and an adhesive film by roll-to-roll, the adhesive film may be unwound from an adhesive film roll wound in a roll shape and laminated on the resin film, After forming a through-hole in the said laminated body and obtaining an adhesive film, you may laminate | stack on a resin film continuously (without winding up an adhesive film once).

When the adhesive film 10a is long, the through holes 14 can be formed at predetermined intervals (that is, in a predetermined pattern) in the longitudinal direction and / or the width direction of the adhesive film 10a. The formation pattern of the through-hole 14 can be appropriately set according to the purpose. Typically, the through-hole 14 is formed when the polarizer 20 is cut to a predetermined size (for example, cutting and punching in the longitudinal direction and / or the width direction) in order to attach the polarizer 20 to an image display device of a predetermined size. It is formed at a position corresponding to the camera unit of the image display device.

C-2-2. Formation of a non-polarizing part As above-mentioned, it is preferable to form a non-polarizing part by forming the low concentration part whose content of a dichroic substance is lower than another site | part. A low concentration part is formed by making arbitrary appropriate decoloring liquids contact the resin film containing a dichroic substance, for example. As the decoloring solution, a basic solution is preferably used. When iodine is used as the dichroic substance, the iodine content in the contact portion can be easily reduced by bringing the basic solution into contact with a desired portion of the resin film. Specifically, the basic solution can penetrate into the resin film by contact. The iodine complex contained in the resin film is reduced by the base contained in the basic solution to become iodine ions. By reducing the iodine complex to iodine ions, the transmittance of the contact portion can be improved. And the iodine which became the iodine ion moves to the solvent of a basic solution from a resin film. The transparency of the low concentration part obtained in this way can be maintained well. Specifically, when the transmittance is improved by destroying the iodine complex, iodine remaining in the resin film may form an iodine complex again with the use of the polarizer, and the transmittance may decrease. Such a problem is prevented when the content is reduced.

Any appropriate basic compound can be used as the basic compound. 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, an alkali metal and / or alkaline earth metal hydroxide is preferably used, and sodium hydroxide, potassium hydroxide, and lithium hydroxide are more preferably used. A dichroic substance can be ionized efficiently, and a low concentration part can be formed more easily. These basic compounds may be used alone or in combination of two or more.

Any appropriate solvent can be used as a solvent for the basic solution. Specific examples include water, alcohols such as ethanol and methanol, ethers, benzene, chloroform, and mixed solvents thereof. Among these, water and alcohol are preferably used because the ionized dichroic substance can be transferred to the solvent satisfactorily.

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. When the concentration is in such a range, a desired low concentration portion can be formed satisfactorily.

The liquid temperature of the basic solution is, for example, 20 ° C. to 50 ° C. The contact time of the basic solution is set according to, for example, the thickness of the resin film 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 the contact method of the decolorizing liquid. For example, a method of dropping, coating, and spraying a decolorizing solution on a resin film (exposed portion), and a method of immersing a resin film (polarizing film laminate) in the decolorizing solution are exemplified. By using the said adhesive film, it can prevent that a decoloring liquid contacts other than a desired site | part. As a result, it is possible to satisfactorily form a non-polarizing part having a desired shape.

In the illustrated example, one side of the resin film 20 is protected by the adhesive film 10a, and the other side is protected by the protective film 30 and the surface protective film 40. Thus, it is preferable to protect the other side of the resin film (the side on which the adhesive film is not disposed) when forming the non-polarizing portion. The protective film can be used as it is as a protective film for a polarizer. The surface protective film is temporarily used when manufacturing the polarizer. Therefore, the adhesive film 10a can function as a surface protective film. In the illustrated example, one side of the resin film 20 is protected by the protective film 30 and the surface protective film 40, but may be protected using only one of them. Further, a photoresist or the like may be used instead of the protective film or the surface protective film. The details of the protective film will be described later.

When forming the non-polarizing part, the resin film is preferably in a state that can be used as a polarizer. Specifically, it is preferable that various treatments such as a swelling treatment, a stretching treatment, a dyeing treatment with the dichroic substance, a crosslinking treatment, a washing treatment, and a drying treatment are performed. In addition, when performing various processes, the resin film formed on the base material may be sufficient as the resin film. The laminated body of a base material and a resin layer can be obtained by the method of apply | coating the coating liquid containing the formation material of the said resin film to a base material, the method of laminating | stacking a resin film on a base material, etc., for example.

The above dyeing treatment is typically performed by adsorbing a dichroic substance. Examples of the adsorption method include a method of immersing a resin film in a staining solution containing a dichroic substance, a method of applying the staining solution to a resin film, and a method of spraying the staining solution onto a resin film. . Preferably, the resin film is immersed in the dyeing solution. It is because a dichroic substance can adsorb | suck favorably.

When iodine is used as the dichroic substance, an aqueous iodine solution is preferably used as the staining solution. The amount of iodine is preferably 0.04 to 5.0 parts by weight per 100 parts by weight of water. In order to increase the solubility of iodine in water, it is preferable to add an iodide to the aqueous iodine solution. As the iodide, potassium iodide is preferably used. The blending amount of iodide is preferably 0.3 to 15 parts by weight with respect to 100 parts by weight of water.

In the above stretching treatment, the resin film is typically uniaxially stretched 3 to 7 times. The stretching direction can correspond to the absorption axis direction of the obtained polarizer.

The resin film may contain boric acid by the above various treatments. For example, boric acid can be contained in the resin film by bringing a boric acid solution (for example, a boric acid aqueous solution) into contact with each other during the stretching treatment and the crosslinking treatment. The boric acid content of the resin film is, for example, 10 to 30% by weight. The boric acid content in the contact portion with the basic solution is, for example, 5% by weight to 12% by weight.

C-2-3. Others The polarizing film laminate (resin film) may be subjected to any appropriate other treatment. Examples of the other treatment include reduction of alkali metal and / or alkaline earth metal. Specifically, after the contact with the basic solution, the alkali metal and / or alkaline earth metal contained in the resin film is reduced in the contact portion where the basic solution is contacted. By reducing the alkali metal and / or alkaline earth metal, a non-polarizing part having excellent dimensional stability can be obtained. Specifically, even in a humid environment, the shape of the low concentration part formed by contact with the basic solution can be maintained as it is.

By bringing a basic solution into contact with the resin film, alkali metal and / or alkaline earth metal hydroxide can remain in the contact portion. Further, by bringing a basic solution into contact with the resin film, an alkali metal and / or alkaline earth metal metal salt can be produced at the contact portion. These can generate hydroxide ions, and the generated hydroxide ions act (decompose and reduce) on the dichroic substance (for example, iodine complex) existing around the contact portion, thereby causing a non-polarized region (low level). Concentration range) can be widened. Therefore, it is considered that by reducing the alkali metal and / or alkaline earth metal, it is possible to suppress the spread of the non-polarized region over time and maintain the desired non-polarized part shape.

As a metal salt which can produce | generate the said hydroxide ion, borate is mentioned, for example. The borate can be generated by neutralizing boric acid contained in the resin film with a basic solution (a solution of an alkali metal hydroxide and / or an alkaline earth metal hydroxide). In addition, borate (metaborate) can be hydrolyzed to generate hydroxide ions as shown in the following formula, for example, when a polarizer is placed in a humidified environment.

(Wherein X represents an alkali metal or alkaline earth metal)

It is preferable to reduce the content of alkali metal and / or alkaline earth metal in the contact portion to 3.6% by weight or less, more preferably 2.5% by weight or less, and still more preferably 1.0% by weight. Reduce so that: The reduction rate is preferably 10% or more, more preferably 40% or more, and further preferably 80% or more. As described above, the alkali metal and / or alkaline earth metal may be present in the contact portion, for example, in the form of a metal compound (hydroxide, metal salt). It can be obtained from an X-ray intensity measured by X-ray analysis using a calibration curve prepared in advance using a standard sample.

In addition, the alkali metal and / or alkaline-earth metal can be previously contained in the resin film by performing various treatments for forming a polarizer. Specifically, an alkali metal and / or an alkaline earth metal can be contained in the resin film by contacting an iodide solution such as potassium iodide. Thus, it is generally considered that the alkali metal and / or alkaline earth metal contained in the polarizer does not adversely affect the dimensional stability of the non-polarizing part.

As the above reduction method, a method of bringing the treatment liquid into contact with the basic solution is preferably used. According to such a method, the content of the alkali metal and / or alkaline earth metal can be reduced by transferring the alkali metal and / or alkaline earth metal from the resin film to the treatment liquid.

Any appropriate method can be adopted as the contact method of the treatment liquid. For example, a method of dropping, coating, and spraying the treatment liquid on the contact portion with the basic solution, and a method of immersing the contact portion with the basic solution in the treatment solution can be mentioned. In addition, it is preferable to make a process liquid contact in the state which bonded the adhesive film to the resin film (especially when the temperature of a process liquid is 50 degreeC or more). According to such a form, it is possible to prevent the polarization characteristics from being deteriorated by the treatment liquid at a portion other than the contact portion with the basic solution.

The treatment liquid may contain any appropriate solvent. Examples of the solvent include water, alcohols such as ethanol and methanol, ether, benzene, chloroform, and mixed solvents thereof. Among these, water and alcohol are preferably used from the viewpoint of efficiently transferring alkali metal and / or alkaline earth metal. Any appropriate water can be used as the water. For example, tap water, pure water, deionized water and the like can be mentioned.

The temperature of the treatment liquid at the time of contact is, for example, 20 ° C. or more, preferably 50 ° C. or more, more preferably 60 ° C. or more, and further preferably 70 ° C. or more. If it is such temperature, an alkali metal and / or alkaline-earth metal can be efficiently transferred to a processing liquid. Specifically, the swelling rate of the resin film can be remarkably improved, and the alkali metal and / or alkaline earth metal in the resin film can be physically removed. On the other hand, the temperature of water is substantially 95 ° C. or less.

The contact time can be appropriately adjusted according to the contact method, the type and temperature of the treatment liquid, the thickness of the resin film, and the like. For example, when immersed in warm water (50 ° C. or higher), the contact time is preferably 10 seconds to 30 minutes, more preferably 30 seconds to 15 minutes, and even more preferably 60 seconds to 10 minutes.

In one embodiment, an acidic solution is used as the treatment liquid. By using an acidic solution, the alkali metal and / or alkaline earth metal hydroxide remaining in the resin film is neutralized, and the alkali metal and / or alkaline earth metal in the resin film is chemically removed. be able to.

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, hydrogen fluoride, and boric acid, and organic acids such as formic acid, oxalic acid, citric acid, acetic acid, and benzoic acid. 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.

Preferably, an acidic compound having a higher acidity than boric acid is suitably used as the acidic compound. It is because it can act also on the metal salt (borate) of the alkali metal and / or alkaline earth metal. Specifically, boric acid can be liberated from the borate and the alkali metal and / or alkaline earth metal in the resin film can be chemically removed.

Examples of the acidity index include an acid dissociation constant (pKa), and an acidic compound having a pKa smaller than that of boric acid (pKa (9.2)) is preferably used. Specifically, pKa is preferably less than 9.2, more preferably 5 or less. The pKa may be measured using any appropriate measuring device, and values described in documents such as the Chemical Handbook, Basic Edition, Rev. 5 (Edited by The Chemical Society of Japan, Maruzen Publishing) may be referred to. For acidic compounds that dissociate in multiple stages, the pKa value can change at each stage. When such an acidic compound is used, one having a pKa value in each stage within the above range is used. In addition, in this specification, pKa means the value in 25 degreeC aqueous solution.

The difference between the pKa of the acidic compound and the pKa of boric acid is, for example, 2.0 or more, preferably 2.5 to 15, and more preferably 2.5 to 13. Within such a range, the alkali metal and / or alkaline earth metal can be efficiently transferred to the treatment liquid.

Examples of acidic compounds that can satisfy the above pKa include hydrochloric acid (pKa: -3.7), sulfuric acid (pK ₂ : 1.96), nitric acid (pKa: -1.8), hydrogen fluoride (pKa: 3 .17), formic acid (pKa: 3.54), oxalic acid (pK ₁ : 1.04, pK ₂ : 3.82), citric acid (pK ₁ : 3.09, pK ₂ : 4.75, pK ₃ : 6.41), acetic acid (pKa: 4.8), benzoic acid (pKa: 4.0), and the like.

The solvent of the acidic solution (treatment liquid) is as described above, and physical removal of the alkali metal and / or alkaline earth metal in the resin film occurs also in this embodiment using the acidic solution as the treatment liquid. obtain.

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 set according to, for example, the thickness of the resin film and the type and concentration of the acidic compound contained in the acidic solution. The contact time is, for example, 5 seconds to 30 minutes.

Another example of the other treatment is removal of the basic solution and / or the treatment solution. Specific examples of the removing method include washing, wiping and removing with a waste cloth, suction removal, natural drying, heat drying, air drying, vacuum drying, and the like. Examples of the cleaning liquid used for cleaning include water (pure water), alcohols such as methanol and ethanol, and mixed liquids thereof. Preferably, water is used. The number of washings is not particularly limited, and may be performed a plurality of times. When removed by drying, the drying temperature is, for example, 20 ° C. to 100 ° C.

The adhesive film is peeled from the resin film (polarizer) at any appropriate timing after the formation of the non-polarizing part. For example, when reducing the alkali metal and / or alkaline earth metal, it is preferable to peel the adhesive film from the resin film after the reduction.

C-3. Polarizing plate The polarizing plate of this invention has the said polarizer. The polarizer is typically used by laminating a protective film on at least one side thereof. 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, and copolymer resins thereof.

The surface of the protective film on which 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.

The thickness of the protective film is preferably 10 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 or an active energy ray curable adhesive. The pressure-sensitive adhesive layer is typically formed of an acrylic pressure-sensitive adhesive.

[Example 1]
A long laminate (surface protective film) having a configuration of ester film (thickness 38 μm) / adhesive layer (thickness 5 μm) / separator (thickness 25 μm) was prepared. A carrier film having a configuration of ester film (thickness 38 μm) / adhesive layer (thickness 5 μm) was bonded to the ester film surface of the laminate to prepare a laminate with a carrier film.
Next, a cutting blade having a depth of 80 μm from the separator surface was inserted into the laminate with a carrier film using a punching device, and half cut into a circle having a diameter of 2.4 mm so as not to penetrate the carrier film.
Subsequently, the carrier film was peeled from the laminate to obtain an adhesive film.

[Example 2]
Adhesion in the same manner as in Example 1 except that a laser cutting machine (CO ₂ laser, wavelength: 9.4 μm, output: 10 W) was used instead of the punching device, and half cut (cutting depth: 80 μm) was used. A film was obtained.

[Comparative Example 1]
An adhesive film was obtained in the same manner as in Example 1 except that the carrier film was bonded to the separator surface of the laminate and half-cut from the ester film (resin substrate) surface.

Examples 1 and 2 and Comparative Example 1 were evaluated as follows.
1. It was confirmed whether or not the perforated residue due to the perforated residue was removed when the carrier film was peeled off.
2. Bonding appearance of adhesive film The separator was peeled off and the adhesive film was bonded to a commercially available polarizer, and the appearance was observed with a microscope.

In Examples 1 and 2, when the carrier film was peeled off, the perforated residue generated by the half cut was completely removed. On the other hand, in Comparative Example 1, when the carrier film was peeled off, the perforated residue was not completely removed. Specifically, only the separator part of the laminate was removed.

The obtained adhesive film was bonded to a polarizer, and the bonded state of the polarizer and the adhesive film was observed. For Comparative Example 1, an adhesive film was bonded to the polarizer after removing the perforated residue in advance.
In Examples 1 and 2, no air bubbles were found between the polarizer and the adhesive film as shown in FIG. 4A, but in Comparative Example 1, the periphery of the through-hole was shown in FIG. 4B. In FIG. 2, bubbles were mixed between the polarizer and the adhesive film.

[Example 3]
(Preparation of polarizing plate)
As the base material, an amorphous isophthalic acid copolymerized polyethylene terephthalate (IPA copolymerized PET) film (thickness: 100 μm) having a long water absorption rate of 0.75% and Tg of 75 ° C. was used. One side of the substrate was subjected to corona treatment, and polyvinyl alcohol (degree of polymerization 4200, saponification degree 99.2 mol%) and acetoacetyl-modified PVA (degree of polymerization 1200, degree of acetoacetyl modification 4.6) were applied to this corona-treated surface. %, A saponification degree of 99.0 mol% or more, an aqueous solution containing 9: 1 ratio of Nippon Gosei Kagaku Kogyo Co., Ltd., trade name “Gosefimer Z200”) was applied and dried at 25 ° C. to a thickness of 11 μm. A PVA resin layer was formed to prepare a laminate.
The obtained laminate was uniaxially stretched in the longitudinal direction (longitudinal direction) 2.0 times between rolls having different peripheral speeds in an oven at 120 ° C. (air-assisted stretching).
Next, the laminate was immersed in an insolubilization bath (a boric acid aqueous solution obtained by blending 4 parts by weight of boric acid with respect to 100 parts by weight of water) for 30 seconds (insolubilization treatment).
Subsequently, it was immersed in a dyeing bath having a liquid temperature of 30 ° C. while adjusting the iodine concentration and the immersion time so that the polarizing plate had a predetermined transmittance. In this example, 0.2 parts by weight of iodine was blended with 100 parts by weight of water and immersed in an aqueous iodine solution obtained by blending 1.5 parts by weight of potassium iodide (dyeing treatment). .
Subsequently, it was immersed for 30 seconds in a crosslinking bath having a liquid temperature of 30 ° C. (a boric acid aqueous solution obtained by blending 3 parts by weight of potassium iodide and 3 parts by weight of boric acid with respect to 100 parts by weight of water). (Crosslinking treatment).
Thereafter, the laminate was immersed in a boric acid aqueous solution (an aqueous solution obtained by blending 4 parts by weight of boric acid and 5 parts by weight of potassium iodide with respect to 100 parts by weight of water) at a liquid temperature of 70 ° C. However, uniaxial stretching was performed in the longitudinal direction (longitudinal direction) between rolls having different peripheral speeds so that the total stretching ratio was 5.5 times (in-water stretching).
Thereafter, the laminate was immersed in a cleaning bath (an aqueous solution obtained by blending 4 parts by weight of potassium iodide with respect to 100 parts by weight of water) at a liquid temperature of 30 ° C. (cleaning treatment).
Subsequently, a PVA resin aqueous solution (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “GOHSEPIMAR (registered trademark) Z-200”, resin concentration: 3% by weight) is applied to the surface of the PVA resin layer of the laminate. Then, a protective film (thickness 25 μm) was bonded, and this was heated in an oven maintained at 60 ° C. for 5 minutes. Thereafter, the substrate was peeled from the PVA resin layer to obtain a polarizing plate (polarizer (transmittance 42.3%, thickness 5 μm) / protective film).

(Formation of transparent part)
The pressure-sensitive adhesive film obtained in Example 1 was bonded to the polarizer side of the obtained polarizing plate by peeling off the separator, thereby obtaining a polarizing film laminate.
A sodium hydroxide aqueous solution (1.0 mol / L (1.0 N)) at room temperature was dropped onto a portion where the polarizer was exposed from the adhesive film of the obtained polarizing film laminate, and left for 60 seconds. Thereafter, the dropped sodium hydroxide aqueous solution was removed with a waste cloth, and then the adhesive film was peeled off to obtain a polarizing plate (polarizer) on which a transparent portion was formed.

[Example 4]
A polarizing plate (polarizer) on which a transparent portion was formed was obtained in the same manner as in Example 3 except that the adhesive film obtained in Example 2 was used.

[Comparative Example 2]
A polarizing plate (polarizer) having a transparent portion was obtained in the same manner as in Example 3 except that the adhesive film obtained in Comparative Example 1 was used. In addition, about the adhesive film obtained by the comparative example 1, it bonded together after removing perforated debris beforehand.

The following measurements were performed on the transparent portions of the polarizers obtained in Examples 3 and 4 and Comparative Example 2.
1. Transmittance (Ts)
The measurement was performed using a spectrophotometer (product name “DOT-3” manufactured by Murakami Color Research Laboratory Co., Ltd.). The transmittance (T) is a Y value obtained by correcting the visibility with a 2-degree field of view (C light source) of JlS Z 8701-1982.
2. Iodine content The iodine content in the transparent part of the polarizer was determined by fluorescent X-ray analysis. Specifically, the iodine content of the polarizer was determined from an X-ray intensity measured under the following conditions, using a calibration curve prepared in advance using a standard sample.
・ Analyzer: X-ray fluorescence analyzer (XRF) manufactured by Rigaku Corporation, product name “ZSX100e”
・ Anti-cathode: Rhodium ・ Spectral crystal: Lithium fluoride ・ Excitation light energy: 40 kV-90 mA
・ Iodine measurement line: I-LA
Quantitative method: FP method 2θ angle peak: 103.078 deg (iodine)
・ Measurement time: 40 seconds

In any case, a transparent part having a transmittance of 93% to 94% and an iodine content of 0.15% by weight or less is formed, and these can function as a non-polarizing part. The shape of the non-polarizing portion of the polarizer of Examples 3 and 4 is a circle having a diameter of 2.4 mm corresponding to the shape of the through-hole of the adhesive film, whereas the shape of the non-polarizing portion of the polarizer of Comparative Example 2 Since the aqueous solution of sodium hydroxide soaked into the bubbles mixed between the polarizer and the adhesive film, a shape corresponding to the through-hole of the adhesive film was not obtained (not circular).

After forming the transparent portion in Example 3 (after removing the aqueous sodium hydroxide solution with a waste cloth), hydrochloric acid (1.0 mol / L (1.0 N)) at room temperature was hydroxylated without peeling off the adhesive film. It was dripped at the contact part with sodium aqueous solution, and left to stand for 30 seconds. Thereafter, the dropped hydrochloric acid was removed with a waste cloth. The sodium content of the transparent part before and after contact with hydrochloric acid was determined by fluorescent X-ray analysis. Specifically, the sodium content of the transparent portion was determined from a calibration curve prepared in advance using a standard sample from the X-ray intensity measured under the following conditions.
・ Analyzer: X-ray fluorescence analyzer (XRF) manufactured by Rigaku Denki Kogyo Co., Ltd. Product name “ZSX100e”
・ Anti-cathode: Rhodium ・ Spectral crystal: Lithium fluoride ・ Excitation light energy: 40 kV-90 mA
・ Sodium measurement line: Na-KA
・ Quantitative method: FP method ・ Measurement time: 40 seconds

The sodium content of the transparent part was 4.0% by weight before contact with hydrochloric acid and 0.04% by weight after contact with hydrochloric acid. In addition, when the polarizing plate on which the transparent portion was formed was placed in an environment of 65 ° C./90% RH for 500 hours, the size of the transparent portion contacted with hydrochloric acid hardly changed before and after the humidification test. The transparent part not contacted with hydrochloric acid was about 1.3 times larger in size.

The pressure-sensitive adhesive film obtained by the production method of the present invention can be suitably used as a surface protective film when a predetermined portion of an object is selectively processed. The polarizer obtained by the production method 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.

1 Polarizer (resin film)
2 Non-polarizing part 10 Laminated body 10a Adhesive film 11 Resin base material 12 Adhesive layer 13 Separator 14 Through-hole 20 Resin film 21 Exposed part 30 Protective film 40 Surface protective film 100 Polarized film laminated body

Claims (15)

1. Preparing a laminate having a resin base material, a pressure-sensitive adhesive layer provided on one surface of the resin base material, and a separator temporarily attached to the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer; and
   A method for producing an adhesive film, comprising: cutting from the separator side of the laminate to form a through hole integrally penetrating the separator, the adhesive layer, and the resin substrate.
2. The manufacturing method of the adhesive film of Claim 1 which forms the said through-hole in the state which applied the contact material to the resin base material side of the said laminated body.
3. The method for producing a pressure-sensitive adhesive film according to claim 2, wherein the through-hole is formed by cutting from the separator surface to the middle of the pad.
4. The manufacturing method of the adhesive film of Claim 2 or 3 with which the said adhesive material is bonded together by the said laminated body with the adhesive.
5. The method for producing an adhesive film according to any one of claims 2 to 4, further comprising removing the contact material from the laminate.
6. The method for producing an adhesive film according to any one of claims 1 to 5, wherein the through hole is formed by cutting with a cutting blade.
7. The method for producing an adhesive film according to any one of claims 1 to 5, wherein the through hole is formed by laser light irradiation.
8. A method for producing a film, wherein the adhesive film obtained by the production method according to any one of claims 1 to 7 is bonded to a film, and a portion corresponding to the through hole of the film is selectively treated.
9. Peeling the separator from the adhesive film obtained by the production method according to claim 1, and
   A method for producing a polarizer, comprising: adhering an adhesive film from which the separator has been peeled off to a resin film containing a dichroic substance, and forming a non-polarizing portion at a portion corresponding to the through hole of the adhesive film of the resin film. .
10. The through hole is formed by cutting with a cutting blade,
    The pressure-sensitive adhesive film from which the separator has been peeled has a resin base material and a pressure-sensitive adhesive layer provided on one surface of the resin base material, and a through-hole that integrally penetrates the resin base material and the pressure-sensitive adhesive layer The method for producing a polarizer according to claim 9, wherein a peripheral edge of the through hole on the pressure-sensitive adhesive layer side is formed in an arc surface.
11. The method for producing a polarizer according to claim 9 or 10, further comprising peeling the adhesive film from the resin film containing the dichroic material after forming the non-polarizing part.
12. The method for producing a polarizer according to any one of claims 9 to 11, wherein the non-polarizing part is formed by bringing a basic solution into contact with the resin film containing the dichroic substance.
13. The method for producing a polarizer according to claim 12, wherein the basic solution contains a hydroxide of an alkali metal and / or an alkaline earth metal.
14. The method for producing a polarizer according to claim 12 or 13, further comprising reducing alkali metal and / or alkaline earth metal contained in the resin film in a contact portion with the basic solution.
15. The manufacturing method of the polarizer of Claim 14 which reduces the said alkali metal and / or alkaline-earth metal in the state which bonded the said adhesive film to the resin film containing the said dichroic substance.
    
    

Images