TWI699421B - Manufacturing method of adhesive film and manufacturing method of polarizer - Google Patents

Abstract

The present invention provides a method for manufacturing an adhesive film and a method for manufacturing a polarizer using the adhesive film. The adhesive film is suitable for use as a surface protection film when selectively processing predetermined parts of an object. The manufacturing method of the adhesive film of the present invention includes the following steps: preparing a laminate having a resin substrate, an adhesive layer provided on one side of the resin substrate, and a separator temporarily attached to the adhesive surface of the adhesive layer; And, the through hole is formed by cutting from the separator side of the laminate to form a through hole that integrally penetrates the separator, the adhesive layer and the resin base material.

Description

Manufacturing method of adhesive film and manufacturing method of polarizer Technical field

The invention relates to a method for manufacturing an adhesive film and a method for manufacturing a polarizer. More specifically, the present invention relates to a method of manufacturing an adhesive film with through holes, and a method of manufacturing a polarizer with a non-polarizing portion using the adhesive film.

Background technique

Adhesive films are excellent in processability and can be imparted with various characteristics, so they are used in a wide range of applications. For example, it is desired to be used as a surface protection film when selectively processing a predetermined part of an object.

However, video display devices such as mobile phones and notebook personal computers (PCs) sometimes carry internal electronic components such as cameras. For the purpose of improving the camera performance of such image display devices, various reviews are currently being conducted (for example, Patent Documents 1 to 6). However, due to the rapid spread of smartphones and touch panel-type information processing devices, it is expected that camera performance can be further improved. In addition, in order to cope with the diversification of the shape and high performance of the image display device, a polarizing plate with partial polarization performance is required.

Advanced technical literature Patent literature

Patent Document 1: Japanese Patent Application Publication No. 2011-81315

Patent Document 2: Japanese Patent Application Publication No. 2007-241314

Patent Document 3: Specification of US Patent Application Publication No. 2004/0212555

Patent Document 4: JP 2012-137738 A

Patent Document 5: Korean Published Patent No. 10-2012-0118205

Patent Document 6: Specification of US Patent Application Publication No. 2014/0118826

Summary of the invention

The present invention is completed to solve the above-mentioned conventional problems, and its main purpose is to provide an adhesive film suitable for use as a surface protection film when selectively processing predetermined parts of an object (such as a polarizer). Another object of the present invention is to provide a polarizer, which can realize multi-function and high-performance of electronic components such as image display devices.

The manufacturing method of the adhesive film of the present invention includes the following steps: preparing a laminate having a resin substrate, an adhesive layer provided on one side of the resin substrate, and a partition of the adhesive surface temporarily attached to the adhesive layer And, forming a through hole, cut from the separator side of the laminate, forming a through hole integrally penetrating the separator, the adhesive layer, and the resin substrate.

In one embodiment, the through hole is formed in a state where the abutting material has been in contact with the resin base material side of the laminate.

In one embodiment, the through hole is formed by cutting into the contact material from the surface of the separator.

In one embodiment, the contact material is adhered to the laminated body by an adhesive.

In one embodiment, the method of manufacturing the adhesive film further includes the step of removing the abutting material from the laminate.

In one embodiment, the formation of the through hole is performed by cutting with a cutting knife.

In one embodiment, the formation of the above-mentioned through hole is performed by laser light irradiation.

According to another aspect of the present invention, a method for manufacturing a thin film is provided. In this method, the adhesive film produced by the above manufacturing method is adhered to the film, and the part of the film corresponding to the through hole is selectively processed.

According to another aspect of the present invention, a method for manufacturing a polarizer is provided. The manufacturing method of the polarizer includes the following steps: peeling the separator from the adhesive film produced by the manufacturing method; and bonding the adhesive film of the peeled separator to a resin film containing a dichroic substance, Then, a non-polarized portion is formed on the resin film corresponding to the through hole of the adhesive film.

In one embodiment, the adhesive film of the peeled separator has a resin substrate and an adhesive layer provided on one surface of the resin substrate, and a through hole is formed integrally penetrating the resin substrate and the adhesive layer. The through hole The side periphery of the adhesive layer is formed as an arc surface.

In one embodiment, the method for manufacturing the polarizer further includes the step of: after forming the non-polarizing portion, peeling the adhesive film from the resin film containing the dichroic substance.

In one embodiment, the non-polarizing portion is formed by contacting the resin film containing the dichroic substance with an alkaline solution.

In one embodiment, the alkaline solution contains alkali metal and/or alkaline earth metal hydroxides.

In one embodiment, the manufacturing method of the polarizer further includes the following step: reducing the alkali metal and/or alkaline earth metal contained in the resin film in the contact portion with the alkaline solution.

In one embodiment, the alkali metal and/or alkaline earth metal is directly reduced in a state where the adhesive film has been 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 suitable for use as a surface protection film when selectively processing a predetermined part of an object (for example, a polarizer). By using such an adhesive film, a non-polarized portion having a desired shape can be formed well. The polarizer prepared by the present invention can realize multi-function and high-function of electronic components, and is suitable for use in electronic components. In addition, the polarizer prepared by the present invention is not only suitable for receiving electronic components such as images or monitors, but also suitable for transmitting electronic components such as LED lights or infrared sensors, and ensures the transparency and light transmission to the naked eye. The straightforward image display device.

1‧‧‧Polarizer (resin film)

2‧‧‧Non-polarized part

3‧‧‧Other parts

10‧‧‧Layered body

10a‧‧‧Adhesive film

11‧‧‧Resin substrate

12‧‧‧Adhesive layer

13‧‧‧Partition

14‧‧‧Through hole

20‧‧‧Resin film

21‧‧‧Exposed part

30‧‧‧Protective film

40‧‧‧Surface protection film

100‧‧‧Polarizing film laminate

Fig. 1 is a cross-sectional view of a laminate according to an embodiment of the present invention.

Fig. 2 is a top view of a polarizer according to an embodiment of the present invention.

Fig. 3 is a cross-sectional view of a polarizing film laminate according to an embodiment of the present invention.

FIG. 4(a) is an observation photograph of the state where the adhesive film of the example has been bonded to the polarizing member, and FIG. 4(b) is an observation photograph of the state where the adhesive film of the comparative example has been bonded to the polarizing member.

The form used to implement the invention

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

The manufacturing method of the adhesive film of the present invention includes the following steps: preparing a laminate having a resin substrate, an adhesive layer provided on one side of the resin substrate, and a partition of the adhesive surface temporarily attached to the adhesive layer And, forming a through hole in the laminate.

A. Layered body

Fig. 1 is a cross-sectional view of a laminate according to an embodiment of the present invention. The laminated body 10 has: a resin substrate 11; an adhesive layer 12 provided on one surface of the resin substrate 11; and a separator 13 temporarily attached to the adhesive surface of the adhesive layer 12. For example, the layered body is a long strip. In this specification, the term "strip shape" refers to an elongated shape with a very long length relative to the width. For example, it includes a length of 10 times or more relative to the width. The slender shape is more than 20 times. In this case, the laminate may be wound into a roll shape.

The resin substrate can function as a substrate for the adhesive film produced. The resin substrate is preferably a film with high hardness (for example, elastic coefficient). This is because deformation of the through hole can be prevented. Specifically, when the produced adhesive film is used (for example, during transportation and/or bonding), even if tension is applied, deformation of the through hole can be prevented.

Examples of materials for forming the resin substrate include ester resins such as polyethylene terephthalate resins, cycloolefin resins such as norbornene resins, olefin resins such as polypropylene, polyamide resins, and polyamide resins. Carbonate resins, these copolymer resins, etc. More desirable is an ester resin (especially a polyethylene terephthalate resin). If it is such a material, the coefficient of elasticity is very high, and it has the advantage that the deformation of the through hole is not easily generated.

The thickness of the resin substrate is typically 20μm~250μm, preferably 30μm~150μm. If it is such a thickness, there is an advantage that the deformation of the through hole described above is unlikely to occur.

The elastic modulus of the resin base material should be 2.2kN/mm ² ~4.8kN/mm ² . If the coefficient of elasticity of the resin substrate is in this range, there is an advantage that the through-hole deformation described above is unlikely to occur. In addition, the coefficient of elasticity is measured in accordance with JIS K 6781.

The tensile elongation of the resin substrate should be 90%~170%. If the tensile elongation of the resin base material is in this range, it has the advantage that it is not easy to break during transportation, for example. In addition, the tensile elongation is measured in accordance with JIS K 6781.

As long as the effect of the present invention can be obtained, the above-mentioned adhesive layer can be used It is formed by any suitable adhesive. For example, the matrix resin of the adhesive may be acrylic resin, styrene resin, and silicone resin. From the viewpoints of the chemical resistance of the adhesive film, the adhesion with the adherend (for example, the adhesion to prevent the treatment liquid from infiltrating during immersion), and the degree of freedom of the adherend, acrylic is preferable Department resin. For example, the adhesive may contain a crosslinking agent, such as isocyanate compounds, epoxy compounds, and acridine compounds. The adhesive may also contain, for example, a silane coupling agent. The blending formula of the adhesive can be appropriately set according to the purpose.

The adhesive layer can be formed by any appropriate method. Specific examples include: a method of coating an adhesive solution on a resin substrate and drying; a method of laminating an adhesive previously formed on a separator on the resin substrate, and the like. For example, the coating method may 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 adhesive layer is preferably 1μm~60μm, more preferably 3μm~30μm. If the thickness is too thin, the adhesion will be insufficient, and air bubbles may enter the adhesion interface. If the thickness is too thick, problems such as bleeding of the adhesive are likely to occur.

The above-mentioned separator may have a function as a protective material for protecting the adhesive layer (adhesive film) until it is used for practical use. In addition, by using the separator, the adhesive film can be wound into a roll well. For example, the separator can include plastics that have been surface-coated with release agents such as silicone-based release agents, fluorine-based release agents, and long-chain alkyl acrylate-based release agents (such as polyterephthalic acid). Ethylene glycol (PET), polyethylene, polypropylene) film, non-woven fabric Or paper etc. The thickness of the partition can be set to any appropriate thickness according to the purpose. The thickness of the separator is, for example, 10 μm to 100 μm.

The above-mentioned laminated body can be produced by any appropriate method. Specifically, it can be produced by laminating a separator on an adhesive layer already formed on a resin substrate, or it can be produced by laminating a resin substrate on an adhesive layer already formed on the separator.

B. Formation of through holes

Next, through holes are formed in the above-mentioned laminate. Specifically, the laminate is cut by any appropriate cutting method to form a through hole that integrally penetrates the resin substrate, the adhesive layer, and the separator. For example, the cutting method may include: using Thomson knife, sharp knife and other cutting knives (punch type), water jet, etc., the method of cutting mechanically; the method of irradiating laser light for cutting.

For example, when a plurality of through holes are formed in the laminated body, the above-mentioned cutter can be suitably used for cutting. The cutting with the cutting knife can be carried out in any suitable style. For example, it can be carried out by using a punching device with a plurality of cutting knives arranged in a predetermined pattern, or by using a device such as an XY plotter to move the cutting knives. According to this, since the movable cutting knife performs cutting corresponding to the predetermined position of the laminated body, the through hole can be formed with high precision at the desired position of the laminated body. In one embodiment, the cutting by the cutter blade can be carried out by appropriately interlocking with the conveyance of the long-shaped laminate while being conveyed by the roller. In more detail, by appropriately adjusting the cutting timing and/or the moving speed of the cutting blade in consideration of the conveying speed of the laminate, a through hole can be formed at a desired position of the laminate. In addition, the above hit The hole device can be a reciprocating method (translation) or a rotating method (rotation).

As long as the laminated body can be cut, the above-mentioned laser can be any suitable laser. It is ideal to use a laser that can emit light in the range of 193nm to 10.6μm. Specific examples include gas lasers such as CO ₂ lasers and excimer lasers; solid lasers such as YAG lasers; and semiconductor lasers. It is more ideal to use CO ₂ lasers.

The irradiation conditions of the laser light can be set to any appropriate conditions, for example, according to the laser used. When a CO ₂ laser is used, the output condition is, for example, 0.1W~250W.

When cutting the laminate, it is advisable to abut the abutting material on one side of the laminate. Specifically, the contact material is contacted to the surface of the laminate on the terminal side in the cutting direction. By using the abutting material, when the abutting material is peeled from the laminate after cutting, it is also possible to simultaneously remove perforation waste. Specifically, the abutting material can be peeled from the laminate in a state where the punching waste is attached to the abutting material. In addition, by using the contact material, deformation of the laminate due to cutting can be suppressed. For example, when cutting with a cutting knife, the deformation of the adhesive layer can be particularly suppressed.

In an ideal embodiment, the through hole is formed by cutting into the contact material from the surface of the laminate. With such a configuration, the through hole that integrally penetrates the resin substrate, the adhesive layer, and the separator can be formed well. In addition, when the abutting material is peeled from the laminate, the piercing waste can be removed favorably.

It is preferable to use a polymer film as the abutting material. The polymer film can use the same film as the above-mentioned resin substrate. Furthermore, a flexible (e.g. low coefficient of elasticity) film like polyolefin (e.g. polyethylene) film can also be used. Yu Yi In the embodiment, it is preferable to use a polymer film having a high hardness (for example, elastic coefficient). This is because the deformation of the laminate due to cutting can be well suppressed. The thickness of the polymer film should be 20μm~100μm.

Preferably, the contact material is bonded to the laminate by an adhesive. By bonding the abutting material to the laminate, it is possible to prevent the displacement of the abutting material during cutting. In addition, when the abutting material is peeled from the laminate, the piercing waste can be removed favorably. Any suitable adhesive can be used for the adhesive of the adhesive as long as it has the adhesive force that can peel off the abutting material from the laminate after cutting. In one embodiment, an adhesive layer is formed on the abutting material in advance. The thickness of the adhesive layer formed on the abutting material is preferably 1 μm to 50 μm.

In one embodiment, it is preferable that the shape of the abutting material corresponds to the shape of the laminate. For example, when the laminated body is a long strip, a long strip of abutting material can be used. With such a shape, when the abutting material is peeled from the laminate, the punching waste can be removed well. In addition, when a plurality of through holes are formed in the laminate, the perforation waste can be continuously removed, and the productivity can be significantly improved.

When forming the through hole, cut from the side of the separator of the laminate. By cutting from the side of the separator, the influence of cutting on the adhesion of the adhesive film produced can be suppressed. Specifically, when cutting with a dicing knife, the adhesive layer of the laminated body may be deformed in response to the dicing knife. If cut from the resin substrate side, the adhesive layer will swell on the adhesive surface side of the produced adhesive film, and a bulge will be formed on the periphery of the through hole. As a result, if the produced adhesive film is adhered to the adherend, air bubbles may be generated around the through hole. On the other hand, if cutting from the side of the separator, although the adhesive layer may be deformed to cater to the cutting blade, however, due to the penetration of the adhesive film produced The perimeter of the hole on the adhesive surface side is in a smooth state (for example, an arc surface), so even if it is adhered to the adherend, the generation of bubbles can be prevented. In addition, by cutting from the separator side, when the abutting material is used, when the abutting material is peeled from the laminate after cutting, the perforation waste can be removed well.

The top view shape of the through hole can be any suitable shape according to the purpose. Specific examples include: circle, oval, square, rectangle, and rhombus. In one embodiment, the top-view shape of the through hole has a shape corresponding to the shape of the desired non-polarized portion in the manufacture of the polarizer described later. Specifically, when the polarizer (described later) of the example shown in the figure is manufactured, the plan view shape of the through hole is made into a small circle. By appropriately configuring the through hole forming mechanism, a through hole having a desired top view shape can be formed. When using a device such as a punching device or an XY plotter, a through hole in a top view corresponding to the shape of the cutting knife (punch type) can be formed.

C. Use case

The adhesive film of the present invention is suitable for use as a surface protection film when, for example, a predetermined part of an object (representatively, a film) is selectively treated. For example, the selective treatment may include: decolorization, coloring, perforation, development, etching, patterning (for example, formation of an active energy ray-curable resin layer), chemical modification, and heat treatment. Hereinafter, as a specific example, a method of manufacturing a polarizer having a non-polarizing portion will be described.

C-1. Polarizing parts

Fig. 2 is a top view of a polarizer according to an embodiment of the present invention. The polarizer 1 is composed of a resin film containing a dichroic substance. The polarizer (resin film) 1 has a non-polarizing portion 2. The non-polarizing part 2 should be made into a dichroic substance The content is lower than the low-concentration part of other parts 3. With this structure, compared to the case where the through hole is formed mechanically (for example, by mechanically punching with a carving knife, a plotter, a waterjet, etc.), it can avoid breakage and peeling. Quality problems such as layer (peeling between layers) and paste bleeding. In addition, the low-concentration portion is due to the low content of the dichroic substance itself. Therefore, compared to the case where the dichroic substance is decomposed by laser light or the like to form the non-polarized portion, the transparency of the non-polarized portion can be maintained well.

In the example shown in the figure, the small circular non-polarizing portion 2 is formed at the center of the upper end of the polarizer 1. However, the number, arrangement, shape, and size of the non-polarizing portion can be appropriately designed. For example, it can be designed according to the position, shape, and size of the camera part of the mounted image display device. Specifically, it can be designed such that the non-polarized portion does not correspond to a portion other than the camera of the image display device (for example, the image display portion).

The transmittance of the non-polarized part (for example, the transmittance measured by light with a wavelength of 550nm at 23°C) is preferably 50% or more, more preferably 60% or more, more preferably 75% or more, and particularly ideal It is more than 90%. If it is such a transmittance, the desired transparency can be ensured. For example, when the non-polarized portion corresponds to the camera portion of the image display device, adverse effects on the shooting performance of the camera can be prevented.

Polarizing parts (except for non-polarizing parts) are suitable for showing absorption dichroism in the wavelength range of 380nm~780nm. The single transmittance (Ts) of the polarizer (except for the non-polarized portion) is preferably 39% or more, more preferably 39.5% or more, more preferably 40% or more, and particularly preferably 40.5% or more. In addition, the theoretical upper limit of the monomer transmittance is 50%, and the practical upper limit is 46%. Also, the single transmittance (Ts) The Y value is measured by JIS Z8701 2 degree field of view (C light source) and corrected for visual sensitivity. For example, it can be measured using a microscope light system (manufactured by Lambda Vision, LVmicro) . The degree of polarization of the polarizer (except for the non-polarized part) is preferably above 99.8%, more preferably above 99.9%, and more preferably above 99.95%.

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, more 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 thinner the thickness, the better the formation of the aforementioned low-concentration portion. Specifically, in the contact with the decolorizing liquid described later, the low-concentration portion can be formed in a shorter time. In addition, the thickness of the part contacting the decolorizing liquid may be thinner than other parts. By making the thickness thin, the thickness difference between the contact part with the decolorizing liquid and other parts can be reduced, and the adhesion with other components such as the protective film can be performed well.

For example, the above-mentioned dichroic substance may include iodine, organic dyes, and the like. These can be used alone or in combination of two or more kinds. It is more desirable to use iodine. This is because the low-concentration part can be formed satisfactorily by contact with the alkaline solution described later.

The aforementioned low-concentration part is a part where the content of the dichroic substance is lower than the aforementioned other parts. 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 more preferably 0.2% by weight or less. If the content of the dichroic substance in the low-concentration part is in this range, the desired transparency can be sufficiently imparted to the low-concentration part. For example, make When the low-density portion corresponds to the camera portion of the image display device, from the viewpoint of both brightness and hue, very excellent shooting performance can be achieved. On the other hand, the lower limit of the content of the dichroic substance in the low-concentration part is usually below the detection limit value. In addition, when iodine is used as the dichroic substance, the iodine content can be obtained from the X-ray intensity measured by fluorescent X-ray analysis, for example, using a calibration curve prepared using a standard sample in advance.

The difference between the content of the dichroic substance in other parts and the content of the dichroic substance in the low-concentration portion is preferably 0.5% by weight or more, and more preferably 1% by weight or more.

Any appropriate resin can be used for the resin forming the resin film. It is preferable to use polyvinyl alcohol-based resin (hereinafter referred to as "PVA-based resin"). For example, PVA-based resins include polyvinyl alcohol and ethylene-vinyl alcohol copolymers. Polyvinyl alcohol can be prepared by saponifying polyvinyl acetate. The ethylene-vinyl alcohol copolymer can be prepared by saponifying an ethylene-vinyl acetate copolymer. The degree of saponification of PVA resins is usually above 85 mol% and less than 100 mol%, preferably 95.0 mol%~99.95 mol%, and more ideally 99.0 mol%~99.93 mol%. The degree of saponification can be determined according to JIS K 6726-1994. By using PVA-based resins with such a degree of saponification, polarizers with excellent durability can be produced. When the saponification is too high, there is a risk of gelation.

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

C-2. Manufacturing method of polarizing parts

The manufacturing method of the above-mentioned polarizing member includes the following steps: bonding the adhesive film of the separated separator to a resin film containing a dichroic substance to prepare a polarizing film laminate; and, in the through hole of the corresponding adhesive film of the resin film The part formed the non-polarized part.

C-2-1. Polarizing film laminate

The separator is peeled off from the adhesive film prepared 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 an embodiment of the present invention. The polarizing film laminate 100 has: a resin film (polarizer) 20 containing a dichroic substance; an adhesive film 10a arranged on one side of the resin film 20 (upper side in the example of the figure); and a protective film 30 The surface protection film 40 is arranged on the other side of the resin film 20 (the lower side in the example shown in the figure). The adhesive film 10a is adhered to the resin film 20 by the adhesive layer 12 thereof. The through hole 14 already formed in the adhesive film 10a has an exposed portion 21 where the resin film 20 is exposed on one side of the polarizing film laminate 100 (the upper side in the illustrated example).

The shape of the adhesive film 10a should correspond to the shape of the resin film 20 to be bonded. For example, when the resin film 20 is elongated, the adhesive film 10a is elongated. In this case, the lamination of the resin film and the adhesive film should be done by roll to roll. The so-called "roller-to-roller" refers to conveying a roll-shaped film while aligning the longitudinal direction of each other and layering it. The width dimension of the elongated adhesive film 10a can be designed to be substantially the same as the width dimension of the resin film 20 or greater than the width dimension of the resin film 20.

When the resin film and the adhesive film are laminated by roll-to-roll, the long adhesive film can be rolled out from the adhesive film that has been wound into a roll to be laminated on the resin film, or it can be formed through the above laminate After making the adhesive film through holes, it is laminated on the resin film in a continuous manner (without winding the adhesive film once).

When the adhesive film 10a is elongated, the through holes 14 may be formed in the longitudinal direction and/or the width direction of the adhesive film 10a with predetermined intervals (ie, predetermined patterns). The formation pattern of the through holes 14 can be appropriately set according to the purpose. Representatively, the through hole 14 is formed when the polarizer 20 is installed in an image display device of a predetermined size and is cut (for example, cut and punched in the longitudinal direction and/or width direction) to a predetermined size. The location of the camera section of the image display device.

C-2-2. Formation of non-polarizing part

As mentioned above, it is preferable to form a non-polarized portion by forming a low-concentration portion with a lower content of dichroic substance than other portions. For example, the low-concentration portion can be formed by contacting a resin film containing a dichroic substance with any appropriate decolorizing liquid. Alkaline solution should be used as decolorizing liquid. When iodine is used as a dichroic substance, the iodine content in the contact part can be easily reduced by contacting the desired part of the resin film with an alkaline solution. Specifically, the alkaline solution can penetrate into the inside of the resin film by contact. The iodine complex contained in the resin film can be reduced by the alkali contained in the alkaline solution to form iodide ions. By reducing the iodine complex to iodide ions, the transmittance of the contact portion can be improved. In addition, the iodine constituting the iodide ion moves from the resin film to the solvent of the alkaline solution. The low-concentration part prepared in this way can maintain its transparency well. Specifically, destroying iodine complexes When the transmittance is increased, the iodine remaining in the resin film may re-form iodine complexes with the use of the polarizer and reduce the transmittance. However, when the iodine content is reduced, this problem can be prevented.

Any appropriate basic compound can be used for the above-mentioned basic compound. For example, the alkaline compound may include: hydroxides of alkali metals such as sodium hydroxide, potassium hydroxide, and lithium hydroxide; hydroxides of alkaline earth metals such as calcium hydroxide; inorganic alkali metal salts such as sodium carbonate; Organic alkali metal salts such as sodium acetate; ammonia water, etc. Among these, it is more desirable to use hydroxides of alkali metals and/or alkaline earth metals, and it is more desirable to use sodium hydroxide, potassium hydroxide, and lithium hydroxide. The dichroic substance can be ionized with good efficiency, and the low concentration part can be formed more simply. These basic compounds may be used alone or in combination of two or more kinds.

Any suitable solvent can be used as the solvent of the alkaline solution. Specifically, for example, alcohols such as water, ethanol, methanol, ethers, benzene, chloroform, and mixed solvents of these can be cited. Among them, if the ionized dichroic substance can be transferred to the solvent well, it is preferable to use water and alcohol.

The concentration of the alkaline solution is, for example, 0.01N to 5N, preferably 0.05N to 3N, and more preferably 0.1N to 2.5N. If the concentration is in such a range, a desired low-concentration part can be formed well.

The liquid temperature of the alkaline solution is, for example, 20°C to 50°C. The contact time of the alkaline solution can be set according to, for example, the thickness of the resin film and the type or concentration of the alkaline compound contained in the alkaline solution. The contact time is, for example, 5 seconds to 30 minutes, and preferably 5 seconds to 5 minutes.

The contact method of the decolorizing liquid can be any suitable method. For example In other words, for example, a method of titrating, coating, and spraying a resin film (exposed portion) with a decolorizing solution; and a method of immersing a resin film (polarizing film laminate) in a decolorizing solution. By using the above-mentioned adhesive film, it is possible to prevent the bleaching liquid from coming into contact with areas other than the desired part. As a result, a non-polarized portion having a desired shape can be formed well.

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. Accordingly, when the non-polarizing part is formed, it is also suitable to protect the other side of the resin film (the side where the adhesive film is not arranged). The protective film can be directly used as the protective film of the polarizer. The surface protection film is temporarily used in the manufacture of polarizers. Therefore, the adhesive film 10a can function as a surface protection film. In the example shown in the figure, one side of the resin film 20 is protected by the protective film 30 and the surface protective film 40, however, it is also possible to use either one for protection. Moreover, you may use a photoresist etc. instead of a protective film or a surface protective film. In addition, the details of the protective film are described in the following paragraph.

When forming the non-polarizing part, the resin film is preferably made into a state that can be used as a polarizer. Specifically, various treatments such as swelling treatment, elongation treatment, dyeing treatment using the aforementioned dichroic substance, cross-linking treatment, washing treatment, and drying treatment are suitable. In addition, when various treatments are performed, the resin film may be a resin layer formed on the substrate. The laminate of the substrate and the resin layer can be produced by, for example, the following methods: a method of applying a coating solution containing the above-mentioned resin film forming material to the substrate; a method of laminating a resin film on the substrate.

Representatively, the above-mentioned dyeing treatment is performed by adsorbing dichroic substances. For example, the adsorption method may include: impregnating resin film A method of a dyeing solution containing a dichroic substance; a method of coating the dyeing solution on a resin film; a method of spraying the dyeing solution on a resin film, etc. It is more desirable to immerse the resin film in the dyeing solution. This is because dichroic substances can be adsorbed well.

When iodine is used as a dichroic substance, it is preferable to use an iodine aqueous solution as the above-mentioned dyeing solution. The blending amount of iodine is preferably 0.04 parts by weight to 5.0 parts by weight relative to 100 parts by weight of water. In order to increase the solubility of iodine in water, it is advisable to mix iodide in the iodine aqueous solution. Potassium iodide should be used as iodide. The blending amount of iodide is preferably 0.3 parts by weight to 15 parts by weight relative to 100 parts by weight of water.

In the above-mentioned stretching treatment, the resin film representatively stretches uniaxially from 3 to 7 times. In addition, the extending direction may correspond to the direction of the absorption axis of the obtained polarizer.

Through the above-mentioned various treatments, boric acid can be contained in the resin film. For example, in the above-mentioned stretching treatment and cross-linking treatment, by contacting with a boric acid solution (for example, a boric acid aqueous solution), the resin film may contain boric acid. The boric acid content of the resin film is, for example, 10% by weight to 30% by weight. In addition, the content of boric acid in the contact portion with the alkaline solution is, for example, 5 wt% to 12 wt%.

C-2-3. Other

The above-mentioned polarizing film laminate (resin film) can be subjected to any appropriate other treatment. For example, other treatments may include the reduction of alkali metals and/or alkaline earth metals. Specifically, after contact with the above-mentioned alkaline solution, the alkali metal and/or alkaline earth metal contained in the resin film is reduced in the contact portion of the alkaline solution. By reducing alkali metals and/or alkaline earth metals, a non-polarized portion with excellent dimensional stability can be obtained. Specifically, even in humidified environments Next, the shape of the low-concentration part formed by contact with the alkaline solution can also be directly maintained.

By contacting the resin film with an alkaline solution, hydroxides of alkali metals and/or alkaline earth metals can remain in the contact portion. In addition, by contacting the resin film with an alkaline solution, a metal salt of alkali metal and/or alkaline earth metal can be generated at the contact portion. These can generate hydroxide ions, and the generated hydroxide ions can interact (decompose, reduce) with dichroic substances (such as iodine complexes) existing around the contact part to expand the non-polarized region (low concentration region) ). Therefore, by reducing alkali metals and/or alkaline earth metals, it is generally believed that the non-polarized region can be prevented from expanding for a long time and the desired non-polarized region shape can be maintained.

For example, the metal salt that can generate the above-mentioned hydroxide ion can be exemplified by borate. The boric acid contained in the resin film is neutralized with an alkaline solution (a solution of alkali metal hydroxide and/or alkaline earth metal hydroxide) to generate borate. In addition, for example, by placing the polarizer in a humidified environment, as shown in the following formula, the borate (metaborate) is hydrolyzed to generate hydroxide ions.

(In the formula, X represents alkali metal or alkaline earth metal)

The content of alkali metals and/or alkaline earth metals in contact parts should be reduced It is as low as 3.6% by weight or less, preferably as low as 2.5% by weight or less, and more preferably as 1.0% by weight or less. The reduction rate should be more than 10%, more preferably more than 40%, and more preferably more than 80%. In addition, as mentioned above, alkali metals and/or alkaline earth metals can exist in the contact part, for example, in the state of metal compounds (hydroxides, metal salts), and the above content can be used, for example, by using a standard sample prepared in advance. The line is obtained from the X-ray intensity measured by fluorescent X-ray analysis.

In addition, by performing various treatments for making the polarizing member, the resin film may contain alkali metals and/or alkaline earth metals in advance. Specifically, by contacting a solution of iodide such as potassium iodide, alkali metals and/or alkaline earth metals can be contained in the resin film. Based on this, it is generally believed that the alkali metals and/or alkaline earth metals contained in the polarizing element will not adversely affect the dimensional stability of the non-polarizing portion.

The above reduction method preferably uses the following method: the contact part with the alkaline solution is brought into contact with the treatment liquid. According to this method, alkali metals and/or alkaline earth metals can be moved from the resin film to the treatment liquid to reduce their content.

The contact method of the treatment liquid can be any suitable method. For example, a method of titrating, coating, and spraying the treatment liquid on the contact portion with the alkaline solution; and the method of immersing the contact portion with the alkaline solution in the treatment solution. In addition, it is suitable to directly contact the treatment liquid with the adhesive film bonded to the resin film (especially when the temperature of the treatment liquid is 50°C or higher). According to this form, it is possible to prevent the degradation of the polarization characteristics caused by the treatment liquid in the parts other than the contact part with the alkaline solution.

The above-mentioned treatment liquid may contain any appropriate solvent. For example, Examples of the solvent include alcohols such as water, ethanol, methanol, ether, benzene, chloroform, and mixed solvents of these. Among these, from the viewpoint of effectively migrating alkali metals and/or alkaline earth metals, water and alcohol are preferably used. Any appropriate water can be used for the water. For example, tap water, pure water, deionized water, etc. can be cited.

The temperature of the treatment liquid during the contact is, for example, 20°C or higher, preferably 50°C or higher, more preferably 60°C or higher, and more preferably 70°C or higher. At such a temperature, alkali metals and/or alkaline earth metals can be efficiently transferred to the treatment liquid. Specifically, the swelling rate of the resin film can be significantly increased, and the alkali metals and/or alkaline earth metals 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 or temperature of the treatment liquid, and the thickness of the resin film. For example, when immersed in warm water (above 50°C), the contact time should be 10 seconds to 30 minutes, preferably 30 seconds to 15 minutes, and more ideally 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 can be neutralized, and the alkali metal and/or alkaline earth metal in the resin film can be chemically removed.

Any appropriate acidic compound can be used for the acidic compound contained in the acidic solution. For example, the acidic compound may include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, hydrogen fluoride, and boric acid; 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, and nitric acid. Acidification The compound can be used alone or in combination of two or more kinds.

It is more desirable that the above-mentioned acidic compounds are suitable to use acidic compounds with stronger acidity than boric acid. This is because it can also interact with metal salts (borates) of the above-mentioned alkali metals and/or alkaline earth metals. Specifically, boric acid can be freed from borate to chemically remove alkali metals and/or alkaline earth metals in the resin film.

For example, the above-mentioned index of acidity can be exemplified as: acid dissociation constant (pKa), and it is preferable to use an acidic compound with a pKa smaller than that of boric acid (9.2). Specifically, pKa is preferably less than 9.2, and more preferably 5 or less. The pKa can be measured using any appropriate measuring device, and it can also refer to the value disclosed in literature such as the revised 5th edition of the Basic Handbook of Chemistry (Edited by the Chemical Society of Japan, Maruzen Publishing). Furthermore, if it is an acidic compound that dissociates in multiple stages, the value of pKa can be changed at each stage. When such an acidic compound is used, an acidic compound whose pKa value at each stage is all within the above range can be used. In addition, in this specification, pKa refers to the value in an aqueous solution at 25°C.

The difference between the pKa of the acidic compound and the pKa of the boric acid is, for example, 2.0 or more, preferably 2.5-15, and more preferably 2.5-13. If it is in this range, alkali metals and/or alkaline earth metals can be efficiently transferred to the treatment liquid.

For example, 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), and 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), etc. .

In addition, the solvent of the acidic solution (treatment liquid) is as described above, and even in the present form in which the acidic solution is used as the treatment liquid, the alkali metal and/or alkaline earth metal in the resin film can be physically removed.

The concentration of the acidic solution is, for example, 0.01N~5N, preferably 0.05N~3N, and more preferably 0.1N~2.5N.

The liquid temperature of the aforementioned acidic solution is, for example, 20°C to 50°C. The contact time of the acidic solution can be set according to the thickness of the resin film and the type or concentration of acidic compounds contained in the acidic solution, for example. The contact time is, for example, 5 seconds to 30 minutes.

Other examples of the above-mentioned other treatment include the removal of the above-mentioned alkaline solution and/or treatment liquid. Specific examples of the removal method include washing, wiping removal with rags, etc., suction removal, natural drying, heat drying, air blowing drying, and vacuum drying. For example, the cleaning liquid used in the cleaning can include alcohols such as water (pure water), methanol, ethanol, and mixtures thereof. It is more desirable to use water. There is no special restriction on the washing times, and it can be carried out multiple times. When removing by drying, the drying temperature is, for example, 20°C to 100°C.

The adhesive film can be peeled from the resin film (polarizer) at any appropriate timing after the non-polarized portion is formed. For example, when the alkali metal and/or alkaline earth metal is reduced, it is advisable to peel the adhesive film from the resin film after the reduction.

C-3. Polarizing plate

The polarizing plate of the present invention has the above-mentioned polarizing member. Representatively, the above-mentioned polarizer is used by laminating a protective film on at least one side thereof. For example, protect Examples of the film forming materials include: cellulose resins such as diacetyl cellulose and triacetyl cellulose; (meth)acrylic resins; cycloolefin resins; olefin resins such as polypropylene; polyterephthalic acid Ester resins such as ethylene diester resins; polyamide resins; polycarbonate resins; these copolymer resins, etc.

On the side of the protective film that is not laminated with the polarizer, the surface treatment layer can also be hard-coated, anti-reflection treatment, or treatment for the purpose of diffusion or anti-glare.

The thickness of the protective film should be 10μm~100μm. Representatively, the protective film is laminated on the polarizer through the adhesive layer (specifically, the adhesive layer and the adhesive layer). The adhesive layer is typically formed by a PVA-based adhesive or an active energy ray curable adhesive. The adhesive layer represents the upper system formed by acrylic adhesive.

Example

[Example 1]

A long laminate (surface protective film) having a structure of ester film (thickness 38 μm)/adhesive layer (thickness 5 μm)/separator (thickness 25 μm) was prepared. A carrier film having a structure of ester film (thickness 38 μm)/adhesive layer (thickness 5 μm) was bonded to the ester film surface of the laminate, and a laminate having the carrier film was produced.

Next, using a punching device, the laminate with the carrier film was cut into a dicing knife with a depth of 80 μm from the separator surface, and the carrier film was cut into half into a circle with a diameter of 2.4 mm so as not to penetrate the carrier film.

Next, the carrier film was peeled from the laminate, and an adhesive film was produced.

[Example 2]

Except that instead of the punching device, a laser cutter (CO ₂ laser, wavelength: 9.4 μm, output: 10 W) was used to cut in half (cutting depth: 80 μm), the same as in Example 1 was prepared to produce an adhesive film.

[Comparative Example 1]

The adhesive film was prepared in the same manner as in Example 1, except that the carrier film was adhered to the separator surface of the laminate and cut in half from the ester-based film (resin substrate) surface.

The following evaluations were performed for Examples 1 and 2 and Comparative Example 1.

1. Perforated waste

Confirm whether the perforation waste caused by cutting is removed when the carrier film is peeled off.

2. Adhesive appearance of adhesive film

The separator was peeled off to bond the adhesive film to a commercially available polarizer, and its appearance was observed with a microscope.

In Examples 1 and 2, when the carrier film is peeled off, the perforation waste generated by cutting in half can be completely removed. In contrast, in Comparative Example 1, when the carrier film was peeled off, the punching waste could not be completely removed. Specifically, only the separator part of the laminate is removed.

Bond the prepared adhesive film to the polarizer, and observe the bonding state of the polarizer and the adhesive film. In addition, regarding Comparative Example 1, after removing the perforation waste in advance, the adhesive film was bonded to the polarizer.

In Examples 1 and 2, as shown in Figure 4(a), no bubbles were found to be mixed between the polarizer and the adhesive film. However, in Comparative Example 1, as shown in Figure 4(b) As shown, around the through hole, air bubbles are mixed between the polarizer and the adhesive film.

[Example 3]

(Making of polarizing plate)

A long strip of amorphous isophthalic acid copolymerized polyethylene terephthalate (IPA copolymerized PET) film (thickness: 100μm) with a water absorption rate of 0.75% and a Tg of 75°C is used as the substrate. Perform corona treatment on one side of the substrate, and coat the corona treated surface at 25°C containing polyvinyl alcohol (polymerization degree 4200, saponification degree 99.2 mol%) and acetone in a ratio of 9:1 Acetyl-modified PVA (polymerization degree 1200, acetyl-acetyl-denaturation degree 4.6%, saponification degree 99.0 mol% or more, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "GOHSEFIMER Z200") aqueous solution, and dried to form A PVA-based resin layer with a thickness of 11 μm, and a laminate is produced.

The resulting laminate was uniaxially stretched to 2.0 times in the longitudinal direction (long direction) between rollers with different peripheral speeds in an oven at 120°C (air-assisted stretch).

Next, the layered body was immersed in an insolubilization bath (a boric acid aqueous solution prepared by blending 4 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 30°C for 30 seconds (insolubilization treatment).

Next, while adjusting the iodine concentration and the immersion time, the polarizer was immersed in a dye bath at a liquid temperature of 30°C so that the polarizing plate had a predetermined transmittance. Implemented in this In the example, it is immersed in an iodine aqueous solution prepared by blending 0.2 parts by weight of iodine and 1.5 parts by weight of potassium iodide with respect to 100 parts by weight of water for 60 seconds (dyeing treatment).

Next, it was immersed in a cross-linking bath (a boric acid aqueous solution prepared 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 with a liquid temperature of 30°C) for 30 seconds (cross-linking treatment).

Then, while immersing the layered body in an aqueous solution of boric acid at a liquid temperature of 70°C (an aqueous solution prepared by blending 4 parts by weight of boric acid and 5 parts by weight of potassium iodide per 100 parts by weight of water), the layered body was placed on rolls with different peripheral speeds. Uniaxial stretching is carried out in the longitudinal direction (long direction) so that the total stretching ratio is 5.5 times (underwater stretching).

Then, the layered body was immersed in a washing bath (an aqueous solution prepared 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 (washing treatment).

Next, a PVA-based resin aqueous solution (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., brand name "GOHSEFIMER (registered trademark) Z-200", resin concentration: 3% by weight) is coated on the surface of the PVA-based resin layer of the laminate, and a protective film is bonded (Thickness 25μm), and heat it for 5 minutes in an oven maintained at 60°C. Then, the base material was peeled from the PVA-based resin layer, and a polarizing plate (polarizer (transmittance 42.3%, thickness 5 μm)/protective film) was produced.

(Formation of transparent part)

The separator was peeled off, and the adhesive film prepared in Example 1 was adhered to the polarizing member side of the prepared polarizing plate, and a polarizing film laminate was prepared.

Titrate an aqueous solution of sodium hydroxide (1.0mol/L (1.0N)) at room temperature on the part of the polarizer exposed from the adhesive film of the polarizing film laminate prepared, and leave it for 60 seconds. Then, use a rag to remove the titrated sodium hydroxide aqueous solution and peel off the adhesive film to prepare a polarizing plate (polarizer) with a transparent portion.

[Example 4]

Except that the adhesive film prepared in Example 2 was used, the same as in Example 3 was used to prepare a polarizing plate (polarizer) having a transparent portion.

[Comparative Example 2]

Except that the adhesive film prepared in Comparative Example 1 was used, the same as in Example 3 was used to prepare a polarizing plate (polarizer) having a transparent portion. In addition, regarding the adhesive film prepared in Comparative Example 1, the perforation waste was removed beforehand and then bonded.

The following measurements were performed on the transparent part of the polarizers prepared in Examples 3 and 4 and Comparative Example 2.

1. Transmittance (Ts)

A spectrophotometer (product name "DOT-3" manufactured by Murakami Color Research Institute Co., Ltd.) was used for measurement. The transmittance (T) is the Y value corrected by the visual sensitivity of the 2 degree field of view (C light source) of JIS Z 8701-1982.

2. Iodine content

Calculate the iodine content in the transparent part of the polarizer by fluorescent X-ray analysis. Specifically, the iodine content of the polarizer was obtained from the X-ray intensity measured under the following conditions using a calibration curve prepared using a standard sample in advance.

. Analysis device: Fluorescent X-ray analysis device (XRF) manufactured by Rigaku Denki, product name "ZSX100e"

. On the cathode: rhodium

. Analysis crystal: lithium fluoride

. Excitation light energy: 40kV-90mA

. Iodine measuring line: I-LA

. Quantitative method: FP method

. Peak 2θ angle: 103.078deg (iodine)

. Measurement time: 40 seconds

In any of them, transparent parts having a transmittance of 93% to 94% and an iodine content of 0.15 wt% or less are formed, and these parts can function as non-polarizing parts. The shape of the non-polarizing part of the polarizer of Examples 3 and 4 corresponds to the shape of the through hole of the adhesive film and is a circle with a diameter of 2.4 mm. In contrast, the shape of the non-polarizing part of the polarizer of Comparative Example 2 is due to the mixing of the polarizer Sodium hydroxide aqueous solution penetrated into the bubbles between the adhesive film and the adhesive film, so the shape of the through hole corresponding to the adhesive film (not circular) could not be obtained.

In Example 3, after the transparent part was formed (after removing the sodium hydroxide aqueous solution with a rag), the adhesive film was not peeled off, and normal temperature hydrochloric acid (1.0mol/L (1.0N) was titrated at the contact part with the sodium hydroxide aqueous solution) ) And leave it for 30 seconds. Then, remove the titrated hydrochloric acid with a rag. By fluorescent X-ray analysis, the sodium content of the transparent part before and after the hydrochloric acid contact was determined. Specifically, the sodium content of the transparent part is obtained from the X-ray intensity measured under the following conditions using a calibration curve prepared using a standard sample in advance.

. Analysis device: manufactured by Rigaku Denki Kogyo Fluorescent X-ray Analyzer (XRF) Product name "ZSX100e"

. On the cathode: rhodium

. Analysis crystal: lithium fluoride

. Excitation light energy: 40kV-90mA

. Sodium determination line: Na-KA

. Quantitative method: FP method

. Measurement time: 40 seconds

The sodium content of the transparent part was 4.0% by weight before the hydrochloric acid contact, and 0.04% by weight after the hydrochloric acid contact. In addition, when the polarizing plate with the transparent part was placed in an environment of 65°C/90%RH for 500 hours, the size of the transparent part in contact with hydrochloric acid hardly changed before and after the humidification test. The size of the transparent part becomes approximately 1.3 times larger.

Industrial availability

The adhesive film produced by the manufacturing method of the present invention can be suitably used as a surface protection film when selectively treating a predetermined part of an object. The polarizer manufactured by the manufacturing method of the present invention can be suitably used in image display devices (liquid crystal display devices, organic EL elements) with cameras such as mobile phones such as smartphones, notebook PCs, and tablet PCs.

10‧‧‧Layered body

11‧‧‧Resin substrate

12‧‧‧Adhesive layer

13‧‧‧Partition

Claims (10)

A method for manufacturing an adhesive film, wherein the adhesive film is used to selectively decolorize a predetermined part of the adherend, that is, a resin film containing a dichroic substance, through a through hole. The manufacturing method includes the following steps: Prepare a laminate, the laminate having a resin substrate, an adhesive layer provided on one side of the resin substrate, and a separator temporarily attached to the adhesive surface of the adhesive layer; and forming through holes from the foregoing laminate The separator side is cut to form a through hole that integrally penetrates the separator, the adhesive layer, and the resin base material. According to the manufacturing method of the adhesive film of Claim 1, the said through-hole is formed in the state in which the contact material was contact|abutted to the resin base material side of the said laminated body. Such as the manufacturing method of the adhesive film of claim 2, which cuts from the surface of the separator into the abutment material to form the through hole. The method of manufacturing an adhesive film according to claim 2, wherein the abutting material is adhered to the laminate by an adhesive. For example, the manufacturing method of the adhesive film of claim 2 further includes the following step: removing the abutting material from the laminate. The method for manufacturing an adhesive film according to any one of claims 1 to 5, wherein the formation of the through hole is performed by cutting with a cutting knife. Such as the manufacturing method of the adhesive film of any one of claims 1 to 5, wherein the former The formation of the through hole is performed by laser light irradiation. An adhesive film, which is produced by the manufacturing method of claim 6, and has a resin base material and an adhesive layer provided on one side of the resin base material, and forms an integrally penetrating resin base material and the adhesive layer Through holes, the adhesive layer side peripheral edge of the through holes is formed as an arc surface. A method of manufacturing a film is to adhere an adhesive film made by the manufacturing method of any one of claims 1 to 7 to the film, and selectively process the portion of the film corresponding to the aforementioned through holes. A manufacturing method of a polarizing member, comprising the steps of: peeling off the aforementioned separator from an adhesive film made by the manufacturing method of any one of claims 1 to 7; and bonding the aforementioned adhesive film of the separated separator A non-polarizing part is formed on the resin film containing the dichroic substance, and then on the part of the resin film corresponding to the through hole of the adhesive film.

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