JP6152138B2 - Manufacturing method of polarizer - Google Patents

Description

  The present invention relates to a method for manufacturing a polarizer. In more detail, this invention relates to the manufacturing method of the polarizer which has a non-polarizing part.

  Some image display devices such as mobile phones and notebook personal computers (PCs) are equipped with internal electronic components such as cameras. Various studies have been made for the purpose of improving the camera performance and the like of such an image display device (for example, Patent Documents 1 to 7). 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. In order to realize these demands industrially and commercially, it is desired to manufacture an image display device and / or its components at an acceptable cost. Matters are left behind.

JP 2011-81315 A JP 2007-241314 A US Patent Application Publication No. 2004/0212555 Korean Published Patent No. 10-2012-0118205 Korean Patent No. 10-1293210 JP 2012-137738 A JP 2014-2111548 A

  The present invention has been made to solve the above-described conventional problems, and a main object thereof is a method for manufacturing a polarizer capable of realizing multi-function and high-performance electronic devices such as image display apparatuses. Thus, it is an object of the present invention to provide a method capable of forming a desired non-polarizing portion shape with high accuracy.

In the method for producing a polarizer of the present invention, a surface protective film is laminated on one side of the polarizer via an adhesive layer having a thickness of 10 μm or less, and at least a part of the polarizer is exposed on the one side. A step of producing a polarizing film laminate having a portion, a step of bringing a basic solution into contact with an exposed portion of the polarizing film laminate, and a step of removing the surface protective film from the polarizing film laminate.
In one embodiment, the step of bringing the basic solution into contact with the exposed portion includes immersing the polarizing film laminate in the basic solution.
In one embodiment, the pressure-sensitive adhesive layer contains an acrylic resin.
In one embodiment, the said manufacturing method further includes the process of making an acidic solution contact the exposed part of the said polarizing film laminated body.
In one embodiment, the step of bringing the acidic solution into contact with the exposed portion includes immersing the polarizing film laminate in the acidic solution.
In one embodiment, the polarizing film laminate is elongated.
In another aspect of the present invention, a polarizer is obtained. This polarizer is obtained by the manufacturing method described above.
In still another aspect of the present invention, a polarizing plate is obtained. This polarizing plate includes the polarizer.
In still another aspect of the present invention, an image display device is provided. The image display device includes the polarizing plate.

  The polarizing film laminated body used with the manufacturing method of this invention has laminated | stacked the surface protection film on the one surface side of the polarizer through the 10-micrometer-thick adhesive layer. By using such a polarizing film laminate, a non-polarizing portion having a desired shape can be formed with high accuracy.

It is a schematic sectional drawing of the polarizing film laminated body used by one Embodiment of this invention. It is a schematic plan view explaining an example of the arrangement pattern of the through-hole in the surface protection film used by one Embodiment of this invention. It is a schematic plan view explaining another example of the arrangement pattern of the through-hole in the surface protection film used by one embodiment of this invention. It is a schematic plan view explaining another example of the arrangement pattern of the through-hole in the surface protection film used in one embodiment of the present invention. FIG. 3A is a schematic diagram for explaining a method for measuring hole roughness. This represents the distance a between the non-polarizing part and the non-polarizing part approximate circle when the boundary (solid line) between the polarizer 1 and the non-polarizing part 2 is outside the non-polarizing part approximate circle (broken line). FIG. 3B is a schematic diagram illustrating a method for measuring hole roughness. This represents the distance b between the non-polarizing part and the non-polarizing part approximate circle when the boundary (solid line) between the polarizer 1 and the non-polarizing part 2 is inside the non-polarizing part approximate circle (broken line).

  Hereinafter, although one embodiment of the present invention is described, the present invention is not limited to these embodiments.

A. Manufacturing method of polarizer In the manufacturing method of the present invention, a surface protective film is laminated on one surface side of a polarizer via an adhesive layer having a thickness of 10 μm or less, and at least a part of the polarizer is exposed on the one surface side. A step of producing a polarizing film laminate having the exposed portion, a step of bringing a basic solution into contact with the exposed portion of the polarizing film laminate, and a step of removing the surface protective film from the polarizing film laminate. By using the polarizing film laminate having an exposed portion, only a desired portion of the polarizer (that is, a portion exposed from the exposed portion) can be brought into contact with the basic solution. By bringing the polarizer into contact with the basic solution, the content of the dichroic substance contained in the contact part can be reduced, and the non-polarizing part having a lower content of the dichroic substance than other parts can be obtained. Can be formed.

  Furthermore, in the manufacturing method of this invention, the polarizing film laminated body which laminated | stacked the polarizer and the surface protection film via the adhesive layer of thickness 10 micrometers or less is used. By setting the thickness of the pressure-sensitive adhesive layer to 10 μm or less, it is possible to prevent bubbles from adhering to the exposed portion due to the surface tension of the pressure-sensitive adhesive. As a result, the basic solution is sufficiently in contact with the entire exposed portion, and a non-polarized portion having a desired shape can be formed with high accuracy. In addition, although the polarizer before forming a non-polarization part is an intermediate body of the polarizer which has a non-polarization part obtained by the manufacturing method of this invention strictly, it is only called a polarizer in this specification. A person skilled in the art can easily understand from the description of the present specification whether "polarizer" means an intermediate or a polarizer having a non-polarization part obtained by the production method of the present invention. be able to.

A-1. Production of Polarizing Film Laminate A polarizing film laminate is produced by laminating a surface protective film on one side of a polarizer with a pressure-sensitive adhesive layer having a thickness of 10 μm or less. The polarizing film laminate used in the present invention has an exposed portion where at least a part of the polarizer is exposed on the one surface side.

  FIG. 1 is a schematic cross-sectional view of a polarizing film laminate used in one embodiment of the present invention. In this embodiment, a polarizing plate having a polarizer / protective film configuration is used. In the polarizing film laminate 100, the surface protective film 50 is laminated on the surface of the polarizer 10 of the polarizer 10 / protective film 20 via an adhesive layer 60 having a thickness of 10 μm or less. The surface protective film 50 has a through hole 71. The polarizing film laminate 100 has an exposed portion 51 where the polarizer 10 is exposed from the through hole 71. The surface protective film 50 is detachably laminated on the polarizing plate (substantially, the polarizer 10). It goes without saying that the same procedure can be applied to a polarizer having a form other than that of the polarizing plate (for example, a polarizer that is a single resin film, a laminate of a resin base material / polarizer).

  In one embodiment, the polarizing film laminate 100 may have another surface protective film (the surface protective film 30 in FIG. 1) further laminated on the surface where the surface protective film 50 having a through hole is not laminated. Good. Hereinafter, the surface protective film 50 having a through hole is used as the first surface protective film, and the surface protective film 30 laminated on the side where the surface protective film having the through hole of the polarizing film laminate 100 is not laminated is the second surface. Also called protective film.

  The polarizing film laminate is typically long. The long polarizing film laminate is formed by, for example, laminating a long surface protective film having through holes arranged at predetermined intervals in the long direction and / or the width direction and a long polarizer. Can be obtained. By using a long polarizing film laminate, for example, a step of contacting with a basic solution and a step of contacting with another treatment solution (for example, a step of contacting with an acidic solution) are continuously performed by immersion. be able to. As a result, the productivity of the polarizer can be further improved. Moreover, the elongate polarizing film laminated body may have a some exposed part. Even in such a case, the basic solution can be sufficiently brought into contact with each exposed portion, and a non-polarizing portion having a desired shape can be formed with high accuracy.

  Furthermore, by using a polarizing film laminate, it is possible to obtain a polarizer having a non-polarizing part in a pattern corresponding to the pattern of the exposed part, so that the non-polarizing part is precisely controlled over the entire long polarizer. Can be arranged. As a result, when a polarizer as a final product of a predetermined size is cut from the long polarizer, the quality variation for each final product can be remarkably suppressed. In addition, such a non-polarizing part is selectively and easily formed at the position of the through hole, and thus does not require a complicated device or operation. Further, according to the present embodiment, the position of the non-polarizing portion can be set in accordance with the size of the polarizer as the final product cut and mounted on the image display device and the position of the camera portion of the image display device. The yield in obtaining a sized polarizer is very good.

A-1-1. Polarizer The polarizer is typically composed of a resin film containing a dichroic substance. The resin film is, for example, a polyvinyl alcohol resin (hereinafter referred to as “PVA resin”) film. 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. By contacting with a basic solution as described below, the iodine complex is reduced and the content of iodine is reduced, resulting in the formation of a non-polarizing part with properties suitable for use as a part corresponding to a camera Because it can be done.

  Arbitrary appropriate resin may be used as resin which forms the said resin film. Preferably, a PVA resin is used. Examples of the PVA resin include polyvinyl alcohol and ethylene-vinyl alcohol copolymer. Polyvinyl alcohol is obtained by saponifying polyvinyl acetate. An ethylene-vinyl alcohol copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer. The saponification degree of the PVA resin is usually 85 mol% or more and less than 100 mol%, preferably 95.0 mol% to 99.95 mol%, more preferably 99.0 mol% to 99.93 mol%. is there. The saponification degree can be determined according to JIS K 6726-1994. By using a PVA-based resin having such a saponification degree, a polarizer having excellent durability can be obtained. If the degree of saponification is too high, there is a risk of gelation.

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

  The thickness of the polarizer (resin film) can be set to any appropriate value. The thickness is preferably 30 μm or less, more preferably 25 μm or less, still more preferably 20 μm or less, and particularly preferably less than 10 μm. On the other hand, the thickness is preferably 0.5 μm or more, more preferably 1 μm or more. If it is such thickness, a non-polarizing part can be favorably formed by making it contact with a basic solution. Furthermore, the time for contacting the basic solution can be shortened. Moreover, the thickness of the part contacted with the basic solution may be thinner than other parts. By using a thin resin film, it is possible to reduce the difference in thickness between the part that is in contact with the basic solution and the part that is not in contact with it. Can be done.

  The resin film is preferably in a state capable of functioning as a polarizer after being subjected to various treatments such as swelling treatment, stretching treatment, dyeing treatment with the dichroic substance, crosslinking treatment, washing treatment, and drying treatment. When performing various treatments, the resin film may be a resin layer formed on a substrate. 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 said dyeing | staining process is performed by immersing a resin film in a dyeing liquid, for example. As the staining solution, an aqueous iodine solution is preferably used. The blending amount of iodine is preferably 0.04 to 5.0 parts by weight with respect to 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.

A-1-2. Surface Protective Film The surface protective film 50 is provided with a through hole 71 corresponding to a portion to be brought into contact with the obtained basic solution of the polarizer (that is, a portion corresponding to the exposed portion 51 of the polarizing film laminate).

  Arbitrary appropriate shapes may be employ | adopted for the planar view shape of the through-hole of a surface protection film according to the objective. Specific examples include a circle, an ellipse, a square, a rectangle, and a rhombus. As described above, according to the production method of the present invention, it is possible to prevent the polarizer exposed from the exposed portion and the basic solution from being unable to sufficiently contact due to the adhesion of bubbles, so that more complicated shapes (for example, (Star shape) and / or a small-sized exposed portion can form a non-polarizing portion having a desired shape.

  The through hole of the surface protective film can be formed by, for example, mechanical punching (for example, punching, engraving blade punching, plotter, water jet) or removal of a predetermined portion of the surface protective film (for example, laser ablation or chemical dissolution). .

  The arrangement pattern (formation pattern) of the through holes can be appropriately set according to the purpose. FIG. 2A is a schematic plan view for explaining an example of the arrangement pattern of the through holes of the surface protective film, FIG. 2B is a schematic plan view for explaining another example of the arrangement pattern of the through holes, and FIG. It is a schematic plan view explaining another example of the arrangement pattern of the through holes. For example, as shown in FIG. 2A, the through holes 71 can be arranged at substantially equal intervals in both the longitudinal direction and the width direction of the surface protection film 50. Note that “substantially equidistant in both the longitudinal direction and the width direction” means that the spacing in the longitudinal direction is equal and the spacing in the width direction is equal. The interval in the scale direction and the interval in the width direction need not be equal. For example, when the interval in the longitudinal direction is L1 and the interval in the width direction is L2, L1 = L2 may be satisfied, or L1 ≠ L2. Alternatively, the through holes may be arranged at substantially equal intervals in the longitudinal direction and at different intervals in the width direction; they are arranged at different intervals in the longitudinal direction and substantially in the width direction. May be arranged at equal intervals (none of which are shown). When the through holes are arranged at different intervals in the longitudinal direction or the width direction, the intervals between the adjacent through holes may be all different, or only a part (the interval between specific adjacent through holes) may be different. Good. Moreover, you may prescribe | regulate a some area | region in the elongate direction of a surface protection film, and set the space | interval of the through-hole in a elongate direction and / or the width direction for every area | region.

Further, in one embodiment, as shown in FIG. 2A, the through-hole 71 has a straight line that connects adjacent through-holes in the longitudinal direction substantially parallel to the longitudinal direction, and has a width. A straight line connecting adjacent through holes in the direction may be arranged to be substantially parallel to the width direction. In another embodiment, as shown in FIG. 2B, the through-hole 71 has a straight line connecting adjacent through-holes in the longitudinal direction substantially parallel to the longitudinal direction, and in the width direction. a straight line connecting the adjacent through-holes are arranged so as to have a predetermined angle theta _W in the width direction. In yet another embodiment, as shown in FIG. 2C, in the through hole 71, a straight line connecting adjacent through holes in the longitudinal direction has a predetermined angle θ _L with respect to the longitudinal direction, and A straight line connecting adjacent through holes in the width direction is arranged to have a predetermined angle θ _W with respect to the width direction. θ _L and / or θ _W is preferably more than 0 ° and not more than ± 10 °. Here, “±” means to include both clockwise and counterclockwise directions with respect to the reference direction (long direction or width direction).

The embodiment shown in FIGS. 2B and 2C has the following advantages. When using a long polarizing film laminated body, a non-polarizing part can be formed by a desired pattern (pattern corresponding to the arrangement pattern of a through-hole), carrying a roll. As a result, it is possible to form the non-polarizing portion by precisely controlling the arrangement pattern over the entire long polarizer. Here, depending on the image display apparatus, in order to improve the display characteristics, it may be required to dispose the polarizer at a maximum offset of about 10 ° with respect to the long side or the short side of the apparatus. Since the absorption axis of the polarizer is expressed in the longitudinal direction or the width direction, in such a case, by forming the non-polarizing part having a pattern as shown in FIGS. 2B and 2C, the non-polarizing part and the absorption axis Can be controlled uniformly over the entire long polarizer, and a final product with excellent axial accuracy (and therefore excellent optical properties) can be obtained. Therefore, the direction of the absorption axis of the cut polarizer (for example, cutting in the longitudinal direction and / or the width direction, punching) can be precisely controlled to a desired angle, and for each polarizer. Variation in the direction of the absorption axis can be remarkably suppressed. It goes without saying that the arrangement pattern of the through holes is not limited to the illustrated example. For example, in the through hole 71, a straight line connecting adjacent through holes in the longitudinal direction has a predetermined angle θ _L with respect to the longitudinal direction, and a straight line connecting adjacent through holes in the width direction is It may be arranged to be substantially parallel to the direction. Further, a plurality of regions may be defined in the longitudinal direction of the surface protective film 50, and θ _L and / or θ _W may be set for each region.

  The surface protective film is preferably a film having a high hardness (for example, elastic modulus). This is because deformation of the through-hole can be prevented, and particularly when used as a long polarizing film laminate, deformation of the through-hole during transportation and / or bonding can be prevented. Surface protective film forming materials 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). With such a material, the elastic modulus is sufficiently high and deformation of the through-hole can be prevented. When used as a long polarizing film laminate, even if tension is applied during transportation and / or laminating. There is an advantage that deformation of the through hole is difficult to occur.

  The thickness of the surface protective film can be set to any appropriate value. For example, when used as a long polarizing film laminate, the thickness of the surface protective film is, for example, 30 μm because it has the advantage that deformation of the through-hole hardly occurs even when tension is applied during transportation and / or bonding. ~ 150 μm.

The elastic modulus of the surface protective film is preferably 2.2 kN / mm ^{2 to} 4.8 kN / mm ² . If the elastic modulus of the surface protective film is in such a range, deformation of the through-hole can be prevented, and particularly when used as a long polarizing film laminate, tension is applied during transportation and / or bonding. Also has the advantage that deformation of the through-hole is unlikely to occur. The elastic modulus is measured according to JIS K 6781.

  The tensile elongation of the surface protective film is preferably 90% to 170%. When the tensile elongation of the surface protective film is in such a range, when it is used as a long polarizing film laminate, there is an advantage that it is difficult to break during transportation. The tensile elongation is measured according to JIS K 6781.

A-1-3. Adhesive Layer The thickness of the adhesive layer 60 is 10 μm or less, preferably 5 μm or less. When making it contact with a basic solution using a polarizing film laminated body, a basic solution may not fully contact an exposed part by a bubble adhering to the surface protection film and adhesive layer of an exposed part. When the size of the exposed portion is small or the shape of the exposed portion is complicated, this influence becomes remarkable, and there is a possibility that a non-polarized portion having a desired shape cannot be formed. When the thickness of the pressure-sensitive adhesive layer is in such a range, it is possible to prevent bubbles from attaching to the exposed portion due to the surface tension of the pressure-sensitive adhesive. As a result, the basic solution can be sufficiently brought into contact with the exposed portion, and a polarizer having a non-polarized portion having a desired shape can be obtained.

  The pressure-sensitive adhesive layer is formed using any appropriate composition. The composition for forming an adhesive layer includes, for example, a resin component and any appropriate additive. Any appropriate resin can be used as the base resin of the pressure-sensitive adhesive, and a resin having a glass transition temperature Tg of 0 ° C. or lower is preferable. Specific examples include acrylic resins, silicone resins, rubber resins, and urethane resins. An acrylic resin is preferred because the laminated state of the surface protective film and the polarizer can be maintained well even with a thickness of 10 μm or less.

  As the acrylic resin, an acrylic polymer containing at least one acrylate and / or methacrylate (hereinafter also referred to as (meth) acrylate) having an alkyl group having 1 to 14 carbon atoms is preferable. The acrylic polymer preferably contains 50 wt% to 100 wt% of (meth) acrylate having an alkyl group having 1 to 14 carbon atoms as a monomer component.

  Examples of the (meth) acrylate having an alkyl group having 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, and isobutyl (meth) ) Acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) ) Acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, and the like. These (meth) acrylates may be used alone or in combination of two or more.

  Among them, butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate , N-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate and the like, having an alkyl group having 4 to 14 carbon atoms It preferably contains (meth) acrylate. By including (meth) acrylate having an alkyl group having 4 to 14 carbon atoms, it becomes easy to control the adhesive force, and it has excellent removability.

  The said acrylic polymer may contain arbitrary appropriate other monomer components other than the (meth) acrylate which has a C1-C14 alkyl group. Other monomer components include sulfonic acid group-containing monomers, phosphate group-containing monomers, cyano group-containing monomers, vinyl esters, aromatic vinyl compounds and other monomer components that can contribute to improving cohesion and heat resistance, and carboxyl groups Functional group that acts as a crosslinking base point for improving adhesive strength of monomer containing acid, anhydride group-containing monomer, hydroxyl group-containing monomer, amide group-containing monomer, amino group-containing monomer, epoxy group-containing monomer, N-acryloylmorpholine, vinyl ethers, etc. The monomer component which has is mentioned. Other monomer components may be used alone or in combination of two or more.

  Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, and (meth). Examples include acryloyloxynaphthalene sulfonic acid. Examples of the phosphoric acid group-containing monomer include 2-hydroxyethylacryloyl phosphate. Examples of the cyano group-containing monomer include acrylonitrile. Examples of vinyl esters include vinyl acetate. Examples of the aromatic vinyl compound include styrene.

  Examples of the carboxyl group-containing monomer include (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of the acid anhydride group-containing monomer include maleic anhydride and itaconic anhydride. Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl ( (Meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl acrylate, N-methylol (meth) acrylamide, vinyl alcohol, allyl alcohol, 2-hydroxyethyl Examples include vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. Examples of the amide group-containing monomer include acrylamide and diethyl acrylamide. Examples of the amino group-containing monomer include N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate. Examples of the epoxy group-containing monomer include glycidyl (meth) acrylate and allyl glycidyl ether. Examples of vinyl ethers include vinyl ethyl ether.

  The other monomer component is used, for example, so that the Tg of the resulting polymer is 0 ° C. or less from the viewpoint that the adhesive force can be easily adjusted. In addition, it is preferable that Tg of a polymer is -100 degreeC or more, for example.

  The weight average molecular weight of the acrylic polymer is, for example, 100,000 or more.

  The acrylic polymer can be obtained by any appropriate polymerization method. For example, polymerization methods generally used as synthetic methods for acrylic polymers such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, and the like can be mentioned.

  The composition for forming an adhesive layer may contain a resin other than the base resin as a resin component. Examples of other resins include polyether resins, modified polyether resins, and epoxy resins. When other resins are included, the content of other resins is preferably 20% by weight or less.

  The composition for forming an adhesive layer can contain any appropriate additive in addition to the resin component. For example, crosslinking agent, coupling agent, tackifier, surface lubricant, leveling agent, surfactant, antistatic agent, slipperiness improver, wettability improver, antioxidant, corrosion inhibitor, light Examples thereof include stabilizers, ultraviolet absorbers, polymerization inhibitors, crosslinking accelerators, crosslinking catalysts, inorganic or organic fillers, powders such as metal powders and pigments, particles, and foils.

  Any appropriate crosslinking agent can be used as the crosslinking agent. For example, an isocyanate compound, an epoxy compound, an aziridine compound, and a melamine compound are mentioned. A crosslinking agent may be used independently and may be used in combination of 2 or more type.

  The content of the crosslinking agent is preferably 0.1 parts by weight to 15 parts by weight, and more preferably 2 parts by weight to 10 parts by weight with respect to 100 parts by weight of the resin component.

  The pressure-sensitive adhesive layer can be formed by any appropriate method. Specific examples include a method of applying and drying a pressure-sensitive adhesive forming composition on the surface protective film, a method of forming a pressure-sensitive adhesive layer on a separator, and transferring the pressure-sensitive adhesive layer to the surface protective film. . 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.

  In one embodiment, the surface protective film is an adhesive sheet provided with an adhesive layer having a thickness of 10 μm or less. The surface protective film in this embodiment is a laminate having a resin film used as the surface protective film and an adhesive layer provided on one surface of the resin film, and the resin film and the adhesive layer Through-holes. When the surface protective film is a pressure-sensitive adhesive sheet, the long polarizer and the long surface protective film can be bonded by roll-to-roll, and the production efficiency can be further improved. In this embodiment, a separator can be temporarily attached to the pressure-sensitive adhesive layer in a peelable manner.

  A separator has a function as a protective material which protects an adhesive layer until it uses for practical use. 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. Arbitrary appropriate thickness can be employ | adopted for the thickness of a separator according to the objective. The thickness of the separator is, for example, 10 μm to 100 μm. The separator may be laminated on a laminate of the resin film used as the surface protective film and the pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer is formed on the separator, and the laminate of the separator and the pressure-sensitive adhesive layer is formed on the surface protective film. You may laminate | stack on the resin film used as.

  As described above, in the polarizing film laminate 100, the second surface protective film 30 may be further laminated on the side where the surface protective film 50 is not disposed. As the second surface protective film, a film similar to the surface protective film 50 can be used except that no through hole is provided. Furthermore, as the second surface protective film, a soft (eg, low elastic modulus) film such as a polyolefin (eg, polyethylene) film can be used. By using the second surface protective film, the polarizing plate (polarizer / protective film) can be more appropriately protected in the step of contacting with the basic solution. As a result, the polarizer and the basic solution It is possible to perform the step of contacting the substrate more favorably.

A-2. Step of contacting with basic solution Next, the basic solution is brought into contact with the exposed portion of the polarizing film laminate. By contacting the basic solution, the content of the dichroic material in the exposed portion is reduced, and the non-polarizing portion can be formed by reducing the content of the dichroic material. In addition, as a polarizer used for a polarizing film laminated body, as above-mentioned, the polarizer containing an iodine is preferable. When the polarizer contains iodine as a dichroic substance, the exposed portion of the polarizer and the basic solution are brought into contact with each other to reduce the iodine content of the exposed portion. A polarizing part can be formed. Therefore, it is possible to selectively form the non-polarizing portion in a predetermined portion of the polarizer with very high manufacturing efficiency without complicated operation. When iodine remains in the polarizer, even if the iodine complex is destroyed to form a non-polarizing part, the iodine complex is formed again with the use of the polarizer, and the non-polarizing part has the desired characteristics. There is a risk that it will disappear. In the present invention, iodine itself is removed from the polarizer (substantially, the non-polarizing part). As a result, it is possible to prevent a change in the characteristics of the non-polarizing part accompanying the use of the polarizer.

  The step of bringing the basic solution into contact with the polarizing film laminate can be performed by any appropriate means. For example, immersion, dripping, coating, spraying and the like can be mentioned. As described above, by using the first surface protective film (and the second surface protective film as necessary), the iodine content contained in the polarizer is reduced in portions other than the exposed portion of the polarizing film laminate. Therefore, it becomes possible to form a non-polarizing part only in a desired part by immersion. Specifically, by immersing the polarizing film laminate in the basic solution, only the exposed portion of the polarizing film laminate contacts the basic solution.

  The formation of the non-polarizing part by the basic solution will be described in more detail. After the contact with the exposed part of the polarizing film laminate, the basic solution penetrates into the exposed part (specifically, the polarizer). The iodine complex contained in the polarizer is reduced by the base contained in the basic solution to become iodine ions. When the iodine complex is reduced to iodine ions, the polarizing performance of the polarizer exposed from the exposed portion substantially disappears, and a non-polarized portion is formed in the exposed portion. Moreover, the transmittance | permeability of an exposed part improves by reduction | restoration of an iodine complex. Iodine that has become iodine ions moves from the exposed portion into the solvent of the basic solution. As a result, iodine ions are removed from the polarizer together with the basic solution. In this way, a non-polarizing portion is selectively formed in a predetermined portion of the polarizer, and the non-polarizing portion is stable without change over time. A portion where the basic solution is not desired by adjusting the material, thickness and mechanical properties of the first surface protective film, the concentration of the basic solution, and the immersion time of the polarizing film laminate in the basic solution, etc. (As a result, a non-polarizing part is formed in an undesired part) can be prevented.

  Any appropriate basic compound can be used as the basic compound contained in the basic solution. Examples of basic compounds 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, acetic acid Organic alkali metal salts such as sodium, aqueous ammonia and the like can be mentioned. The basic compound contained in the basic solution is preferably an alkali metal hydroxide, more preferably sodium hydroxide, potassium hydroxide, or lithium hydroxide. By using a basic solution containing an alkali metal hydroxide, the iodine complex can be ionized efficiently, and a non-polarizing 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 the solvent of the basic solution. Specific examples include water, alcohols such as ethanol and methanol, ethers, benzene, chloroform, and mixed solvents thereof. Since iodine ions migrate to the solvent satisfactorily and iodine ions can be easily removed, the solvent is preferably water or alcohol.

  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 of the basic solution is in such a range, the iodine content inside the polarizer can be efficiently reduced, and ionization of the iodine complex in a portion other than the exposed portion can be prevented.

  The liquid temperature of the basic solution is, for example, 20 ° C to 50 ° C. The contact time between the polarizing film laminate (substantially, the exposed portion of the polarizer) and the basic solution depends on the thickness of the polarizer, the type of basic compound contained in the basic solution used, and the basic compound It can be set according to the concentration, and is, for example, 5 seconds to 30 minutes.

  The basic solution can be removed by any appropriate means as necessary after contact with the exposed portion of the polarizer (after formation of the non-polarizing portion). Specific examples of the method for removing the basic solution include wiping removal with a waste cloth, suction removal, natural drying, heat drying, air drying, vacuum drying, washing, and the like. The drying temperature in the case of removing the basic solution by drying is, for example, 20 ° C to 100 ° C.

A-3. Surface Protection Film Removal Step After performing the necessary steps, the surface protection film is removed from the polarizing film laminate. As described above, the surface protective film is detachably attached to the surface of the polarizer via the pressure-sensitive adhesive layer. Therefore, it can be easily removed from the surface of the polarizer after performing the steps necessary for producing a polarizer having a non-polarizing part.

A-4. Other steps The method for producing a polarizer having a non-polarizing part of the present invention includes a step of producing a polarizing film laminate, a step of contacting an exposed part of the polarizing film laminate and a basic solution, and a surface protective film. Any appropriate process other than the removing process may be further included. Examples of other steps include a step of contacting with an acidic solution and a washing step.

A-4-1. Step of contacting with acidic solution The production method of the present invention may further include a step of contacting the polarizing film laminate and the acidic solution. By further including the step of contacting with an acidic solution, the non-polarized portion having a desired size and shape can be maintained more stably (particularly in a humidified environment). The step of contacting with the acidic solution can be performed, for example, after the step of contacting with the basic solution.

  Any appropriate acidic compound can be used as the acidic compound contained in the acidic solution. Examples of the acidic compound include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and hydrogen fluoride, and organic acids such as formic acid, oxalic acid, citric acid, acetic acid, and benzoic acid. The density | concentration of an acidic solution is 0.01N-5N, for example, Preferably it is 0.05N-3N, More preferably, it is 0.1N-2.5N.

  The solvent used for the acidic solution, the temperature of the acidic solution, the contact time with the acidic solution, and the contact method are the same as the conditions that can be employed in the contact step with the basic solution described in the above section A-2. Conditions can be employed.

  The contact step with the acid solution is preferably performed before the surface protective film peeling step (specifically, in the state of a polarizing film laminate). By performing in the state of a polarizing film laminated body, a contact process with an acidic solution can be performed continuously with a contact process with a basic solution.

A-4-2. Cleaning Step The production method of the present invention may further include a cleaning step. The cleaning process may be performed only once or a plurality of times. The cleaning process can be performed at any suitable stage in the process of manufacturing a polarizer having a non-polarizing part. For example, after washing the polarizer brought into contact with the basic solution with any appropriate liquid, the contact step with the acidic solution may be performed, or the contact step with the basic solution and the contact step with the acidic solution are performed. Thereafter, a cleaning step with any appropriate liquid may be performed.

  Any appropriate liquid can be used as the liquid used for cleaning. Examples thereof include pure water, alcohols such as methanol and ethanol, acidic aqueous solutions, and mixed solvents thereof. Moreover, the temperature of the liquid to be used can be set to any appropriate temperature.

B. Polarizer Having Non-Polarizing Portion The polarizer obtained by the method of the present invention may have a non-polarizing portion having a desired shape and size formed with high accuracy. Therefore, the polarizer of the present invention can have excellent functionality and design.

  A polarizer having a non-polarizing portion can be applied to, for example, an image display device including a camera. This is because even when a smaller non-polarizing portion is formed, the camera can sufficiently exhibit the photographing function and the appearance of the obtained image display device can be excellent.

  Any appropriate shape can be adopted as the planar view shape of the non-polarizing part as long as it does not adversely affect the camera performance of the image display device. Further, the transmittance of the non-polarizing part (for example, transmittance measured with light having a wavelength of 550 nm at 23 ° C.) is preferably 50% or more, more preferably 60% or more, and further preferably 75% or more. Yes, particularly preferably 90% or more. With such transmittance, desired transparency as a non-polarizing portion can be ensured. As a result, when the polarizer is arranged so that the non-polarizing part corresponds to the camera part of the image display device, it is possible to prevent an adverse effect on the photographing performance of the camera.

  A non-polarizing part is a part with little dichroic substance content compared with the other part (part which has polarization performance) of a polarizer. The content of the dichroic substance contained in the non-polarizing part is preferably 1.0% by weight or less, more preferably 0.5% by weight or less, and further preferably 0.2% by weight or less. Further, the lower limit value of the dichroic substance content of the non-polarizing part is usually not more than the detection limit value. When the content of the dichroic substance in the non-polarizing part is in such a range, not only the desired transparency is given to the non-polarizing part but also the non-polarizing part is used as a part corresponding to the camera of the image display device In addition, it is possible to realize extremely excellent photographing performance from the viewpoints of both brightness and color. When iodine is used as the dichroic substance, the iodine content of the non-polarizing part is a value obtained from a calibration curve prepared in advance using a standard sample from the X-ray intensity measured by fluorescent X-ray analysis.

  The difference between the content of the dichroic substance contained in the part other than the non-polarizing part of the polarizer (part having the polarization performance) and the content of the dichroic substance contained in the non-polarizing part is preferably 0. It is 5% by weight or more, more preferably 1% by weight or more. The difference between the content of the dichroic substance contained in the part other than the non-polarizing part and the content of the dichroic substance contained in the non-polarizing part is within this range, so that the non-polarizing part is sufficiently transparent. For example, a non-polarizing portion can be suitably used as a portion corresponding to an image display camera.

C. Polarizing plate A polarizer can be provided practically as a polarizing plate. The polarizing plate has a polarizer and a protective film disposed on at least one side of the polarizer. Practically, the polarizing plate has an adhesive layer as the outermost layer. The pressure-sensitive adhesive layer is typically the outermost layer on the image display device side. A separator can be temporarily attached to the pressure-sensitive adhesive layer in a peelable manner.

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

  The polarizing plate may further have any appropriate optical functional layer depending on the purpose. Representative examples of the optical functional layer include a retardation film (optical compensation film) and a surface treatment layer. The protective film may have an optical compensation function (specifically, it may have an appropriate refractive index ellipsoid, an in-plane retardation, and a thickness direction retardation depending on the purpose). ).

  The surface treatment layer may be disposed on the viewing side of the polarizing plate. Typical examples of the surface treatment layer include a hard coat layer, an antireflection layer, and an antiglare layer.

D. Image Display Device An image display device of the present invention includes the polarizer. Examples of the image display device include a liquid crystal display device and an organic EL device. Specifically, the liquid crystal display device includes a liquid crystal panel including a liquid crystal cell and the polarizer disposed on one side or both sides of the liquid crystal cell. The organic EL device includes an organic EL panel in which the polarizer is disposed on the viewing side. The polarizer may be arranged so as to correspond to the camera unit of the image display device on which the non-polarizing unit is mounted.

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

[Production Example 1] Preparation of surface protective film 1 with pressure-sensitive adhesive layer 100 parts by weight of an acrylic resin (acrylic polymer having a weight average molecular weight of 600,000 composed of butyl acrylate / acrylic acid = 95/5) and epoxy-based crosslinking An acrylic pressure-sensitive adhesive 1 was prepared by mixing 5 parts by weight of an agent (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Ltd.).
Thickness after drying the obtained acrylic pressure-sensitive adhesive on a PET film (product name: Diafoil T100C, manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.) having a long shape (width 1200 mm, length 43 m) and thickness 38 μm. Was applied to form an adhesive layer. A separator was bonded to the formed pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive sheet. 1000 circular small holes having a diameter of 2 mm were formed on the obtained adhesive sheet using a picnal blade. Each small hole was formed at intervals of 250 mm in length and 400 mm in width to obtain a surface protective film 1 with an adhesive layer.

[Production Example 2] Production of surface protective film 2 with pressure-sensitive adhesive layer A surface protective film 2 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the pressure-sensitive adhesive layer was changed to 5 µm.

[Production Example 3] Production of surface protective film C1 with pressure-sensitive adhesive layer A surface protective film C1 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the pressure-sensitive adhesive layer was 30 µm.

[Production Example 4] Production of surface protective film C2 with pressure-sensitive adhesive layer A surface protective film C2 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the pressure-sensitive adhesive layer was 20 µm.

[Production Example 5] Production of surface protective film C3 with pressure-sensitive adhesive layer A surface protective film C3 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the pressure-sensitive adhesive layer was 15 µm.

[Production Example 6] Production of surface protective film 3 with pressure-sensitive adhesive layer 100 parts by weight of acrylic resin (acrylic polymer having a weight average molecular weight of 500,000 composed of 2-ethylhexyl acrylate / 2-hydroxyethyl acrylate = 96/4) Acrylic adhesive 2 was prepared by mixing 4 parts by weight of an isocyanate-based crosslinking agent (Nippon Polyurethane Co., Ltd., trade name: Coronate HX).
The obtained acrylic pressure-sensitive adhesive was applied to a PET film (product name: E5000, manufactured by Toyobo Co., Ltd.) having a thickness of 1200 μm and a thickness of 38 μm and a thickness of 10 μm after drying. An agent layer was formed. A separator was bonded to the formed pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive sheet. 1000 circular small holes having a diameter of 2 mm were formed on the obtained adhesive sheet using a picnal blade. Each small hole was formed at intervals of 250 mm in length and 400 mm in width to obtain a protective film 3 with an adhesive layer.

[Production Example 7] Preparation of surface protective film 4 with pressure-sensitive adhesive layer A surface protective film 4 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 6 except that the thickness of the pressure-sensitive adhesive layer was changed to 5 µm.

[Production Example 8] Preparation of surface protective film C4 with pressure-sensitive adhesive layer A surface protective film C4 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 6 except that the thickness of the pressure-sensitive adhesive layer was 30 µm.

[Production Example 9] Production of surface protective film C5 with pressure-sensitive adhesive layer A surface protective film C5 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 6 except that the thickness of the pressure-sensitive adhesive layer was 20 µm.

[Production Example 10] Preparation of surface protective film C6 with pressure-sensitive adhesive layer A surface protective film C6 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 6 except that the thickness of the pressure-sensitive adhesive layer was 15 µm.

[Production Example 11] Preparation of surface protective film 5 with pressure-sensitive adhesive layer A surface protective film 5 with a pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 1 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was changed to 4 mm.

[Production Example 12] Production of surface protective film 6 with pressure-sensitive adhesive layer A surface protective film 6 with a pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 2 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was changed to 4 mm.

[Production Example 13] Production of surface protective film C7 with pressure-sensitive adhesive layer A surface protective film C7 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 3 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was 4 mm.

[Production Example 14] Preparation of surface protective film C8 with pressure-sensitive adhesive layer A surface protective film C8 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 4 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was 4 mm.

[Production Example 15] Preparation of surface protective film C9 with pressure-sensitive adhesive layer A surface protective film C9 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 5 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was 4 mm.

[Production Example 16] Production of surface protective film 7 with pressure-sensitive adhesive layer A surface protective film 7 with a pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 6 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was changed to 4 mm.

[Production Example 17] Production of surface protective film 8 with pressure-sensitive adhesive layer A surface protective film 8 with a pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 7 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was 4 mm.

[Production Example 18] Production of surface protective film C10 with pressure-sensitive adhesive layer A surface protective film C10 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 8 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was 4 mm.

[Production Example 19] Production of surface protective film C11 with pressure-sensitive adhesive layer A surface protective film C11 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 9 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was changed to 4 mm.

[Production Example 20] Production of surface protective film C12 with pressure-sensitive adhesive layer A surface protective film C12 with pressure-sensitive adhesive layer was obtained in the same manner as in Production Example 10 except that the diameter of the small holes formed in the pressure-sensitive adhesive sheet was 4 mm.

<Example 1>
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 between the rolls having different peripheral speeds in the longitudinal direction (longitudinal direction) 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-based resin aqueous solution (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “Gosefimer (registered trademark) Z-200”, resin concentration: 3% by weight) is applied to the surface of the PVA-based resin layer of the laminate. Then, a protective film (thickness 25 μm) was bonded, and this was heated for 5 minutes in an oven maintained at 60 ° C. Then, the base material was peeled from the PVA resin layer to obtain a polarizing plate (width: 1200 mm, length: 43 m) having a transmittance of 42.3% and a thickness of 5 μm.

  Next, the surface protective film 1 with the pressure-sensitive adhesive layer from which the separator was peeled off was bonded to the polarizer-side surface of the obtained polarizing plate via the pressure-sensitive adhesive layer to obtain a laminate. The obtained laminate was immersed in a basic solution at room temperature (aqueous sodium hydroxide solution, 1 mol / L (1N)) for 8 seconds and in 0.1 mol / L (0.1N) hydrochloric acid for 30 seconds. Then, it dried at 60 degreeC, the PET film was peeled, and the polarizing plate provided with the polarizer which has a transparent part was obtained.

[Examples 2 to 8]
A polarizing plate provided with a polarizer having a transparent part was obtained in the same manner as in Example 1 except that each of the surface protective films with the pressure-sensitive adhesive layer described in Table 1 was used.

(Comparative Examples 1-12)
A polarizing plate provided with a polarizer having a transparent part was obtained in the same manner as in Example 1 except that each of the surface protective films with the pressure-sensitive adhesive layer described in Table 1 was used.

About the transparent part of the polarizer formed in each Example and the comparative example, the transmittance | permeability and iodine content were measured with the following method.

1. Transmittance (Ts)
It measured using the spectrophotometer (Murakami Color Research Laboratory Co., Ltd. product name "DOT-3"). The transmittance (T) is a Y value obtained by correcting the visibility with a 2-degree visual field (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 Denki Kogyo
-Counter 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

  The transparent parts of the polarizers obtained in each of the examples and comparative examples all had a transmittance of 90% or more and an iodine content of less than 1% by weight. These transparent portions could function as non-polarizing portions.

[Evaluation method]
The shape matching degree of each transparent part formed on the polarizing plate was measured by the following method. Among the 1000 transparent portions on the polarizer, those having a shape matching degree exceeding 0.05 are 40% or less, ◎, those having 50% or less are ◯, and those having more than 60% are ×. . The results are shown in Table 1.

[Shape consistency]
Using an ultrahigh-speed flexible image processing system (trade name: XG7700, manufactured by Keyence Corporation), edge detection is performed on the non-polarizing part of the polarizer obtained in Examples 1 to 8 and Comparative Examples 1 to 12, and the non-polarizing part An approximate circle was obtained. The distance between the circumference of the approximate non-polarizing part circle (the broken line part in FIGS. 3A and 3B) and the boundary between the polarizer 1 and the non-polarizing part 2 (the solid line part in FIGS. 3A and 3B) is measured every 2 °. The distance was calculated with a total of 180 points. When the boundary between the polarizer 1 and the non-polarizing part 2 is outside the non-polarizing part approximate circle at the measurement point (that is, in the case of FIG. 3A), the distance between the non-polarizing part 2 and the non-polarizing part approximate circle a is measured, and when the boundary between the polarizer 1 and the non-polarization part 2 is inside the non-polarization part approximate circle (that is, in the case of FIG. 3B), the non-polarization part 2 and the non-polarization part approximate circle The distance b was measured. The total value of the maximum value of the distance a and the maximum value of the distance b was calculated as hole roughness. The calculated hole roughness value is the diameter of the small holes formed in the PET film (Examples 1 to 4 and Comparative Examples 1 to 3 and 7 to 9: 2 mm, Examples 5 to 8 and Comparative Examples 4 to 6 and 10 to 12: 4 mm) to obtain the value of the shape matching degree.

  In Examples 1 to 8 using the polarizing film laminate in which the thickness of the pressure-sensitive adhesive layer is 10 μm or less, a polarizer having a non-polarizing portion corresponding to the shape of the small hole formed in the PET film was obtained with a high yield. With a polarizer having such a non-polarizing part, for example, when the non-polarizing part is used so as to correspond to the camera part of the image display device, the alignment processability is improved and the camera can be aligned well. it can. Also in Examples 1 to 4 where the small holes provided in the surface protective film were as small as 2 mm, a polarizer having a non-polarizing part close to the shape of the small holes formed in the PET film was obtained.

  The polarizer obtained by the 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.

DESCRIPTION OF SYMBOLS 10 Polarizer 20 Protective film 30 Surface protective film 50 Surface protective film 60 Adhesive layer 51 Exposed part 71 Through-hole 100 Polarizing film laminated body

Claims (7)

A surface protective film is laminated on one surface side of the polarizer via a pressure-sensitive adhesive layer having a thickness of 10 μm or less, and a polarizing film laminate having an exposed portion where at least a part of the polarizer is exposed is produced on the one surface side. Process,
Contacting the basic solution with the exposed portion of the polarizing film laminate, and
The manufacturing method of the polarizer which has a process of removing this surface protection film from a polarizing film laminated body, and has a non-polarizing part.   The method for producing a polarizer according to claim 1, wherein the step of bringing the basic solution into contact with the exposed portion includes immersing the polarizing film laminate in the basic solution.   The manufacturing method of the polarizer of Claim 1 or 2 with which the said adhesive layer contains acrylic resin.   The manufacturing method of the polarizer in any one of Claim 1 to 3 which further includes the process of making an acidic solution contact the exposed part of the said polarizing film laminated body.   The method for producing a polarizer according to claim 4, wherein the step of bringing the acidic solution into contact with the exposed portion includes immersing the polarizing film laminate in the acidic solution. The step of the exposed portion contacting the basic solution comprises that immersing the polarizing film laminate to the basic solution, and the acid resistance step the polarizing film laminate contacting the acidic solution into the exposed portion solution The manufacturing method of the polarizer of Claim 5 including making it immerse in.   The manufacturing method of the polarizer in any one of Claim 1 to 6 whose said polarizing film laminated body is elongate.