TW201707941A - Method for manufacturing polarizer - Google Patents

Abstract

Provided is a method for manufacturing a polarizer that allows an electronic device such as an image display device to be multifunctional and highly functional and makes it possible to precisely form a non-polarizing section into a desired shape. The method for manufacturing a polarizer according to the present invention comprises a step for stacking a surface protection film on one side of the polarizer with an adhesive layer having a thickness of 10 [mu]m or smaller interposed therebetween and preparing a polarizing film laminate having an exposed section where at least a portion of the polarizer is exposed on the one side, a step for bringing a basic solution into contact with the exposed part of the polarizing film laminate, and a step for removing the surface protection film from the polarizing film laminate.

Description

Method for manufacturing polarizer Technical field

The present invention relates to a method of manufacturing a polarizing member. More specifically, the present invention relates to a method of fabricating a polarizer having a non-polarizing portion.

Background technique

An internal electronic component such as a camera is mounted on an image display device such as a mobile phone or a notebook computer (PC). Various reviews have been made for the purpose of improving the performance of the camera of such an image display device (for example, Patent Documents 1 to 7). However, due to the rapid spread of smart phone and touch panel type information processing devices, it is desired to further improve camera performance and the like. Further, in order to respond to the diversification and high performance of the shape of the image display device, a polarizing plate partially having polarizing performance is required. In order to achieve such demand in industrial and commercial locations, it is desirable to manufacture image display devices and/or their components at an affordable cost, and there are still various issues that need to be reviewed in order to establish such technology.

Prior technical literature Patent literature

Patent Document 1: Japanese Laid-Open Patent Publication No. 2011-81315

Patent Document 2: Japanese Laid-Open Patent Publication No. 2007-241314

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

Patent Document 4: Korean Laid-Open Patent Publication No. 10-2012-0118205

Patent Document 5: Korean Patent No. 10-1293210

Patent Document 6: Japanese Laid-Open Patent Publication No. 2012-137738

Patent Document 7: Japanese Laid-Open Patent Publication No. 2014-211548

Summary of invention

The present invention has been made to solve the above problems, and a main object of the present invention is to provide a method for manufacturing a polarizer capable of realizing multi-function and high performance of an electronic device such as an image display device, which can form a desired high precision. The shape of the non-polarized portion.

The method for producing a polarizing member of the present invention comprises the steps of: transmitting a surface layer protective film of an adhesive layer having a thickness of 10 μm or less on one side of the polarizing member, and forming a polarizing film having an exposed portion exposing at least a portion of the polarizing member on one side thereof a film laminate; contacting the exposed portion of the polarizing film laminate with an alkaline solution; and removing the surface protection film from the polarizing film laminate.

In one embodiment, the step of contacting the exposed portion with the alkaline solution comprises immersing the polarizing film laminate in an alkaline solution.

In one embodiment, the adhesive layer contains an acrylic resin.

In one embodiment, the manufacturing method further includes a step of bringing the exposed portion of the polarizing film laminate into contact with an acidic solution.

In one embodiment, the step of contacting the exposed portion with the acidic solution includes immersing the polarizing film laminate in an acidic solution.

In one embodiment, the step of contacting the exposed portion with the alkaline solution comprises immersing the polarizing film laminate in an alkaline solution, and the step of contacting the exposed portion with the acidic solution comprises immersing the polarizing film laminate in the layer In an acidic solution.

In one embodiment, the polarizing film laminate is elongated.

Another aspect of the invention produces a polarizer. The polarizer is produced by the above manufacturing method.

In still another aspect of the invention, a polarizing plate is produced. The polarizing plate includes the above polarizing member.

In still another aspect of the invention, an image display device is provided. The image display device includes the above polarizing plate.

The polarizing film layering system used in the production method of the present invention transmits the surface layer protective film of the adhesive layer having a thickness of 10 μm or less on one side of the polarizing member. By using such a polarizing film laminate, the non-polarized portion of a desired shape can be formed with high precision.

1,10‧‧‧ polarizer

2‧‧‧Non-polarized section

20‧‧‧Protective film

30,50‧‧‧Surface protection film

51‧‧‧Exposed Department

60‧‧‧Adhesive layer

71‧‧‧through holes

100‧‧‧Polarized film laminate

a, b‧‧‧ the distance between the non-polarized part and the non-polarized part

Fig. 1 is a schematic cross-sectional view showing a polarizing film laminate used in an embodiment of the present invention.

2A is a view showing a surface protection film used in an embodiment of the present invention. A schematic plan view of an example of a through-hole arrangement pattern.

Fig. 2B is a schematic plan view showing another example of a through hole arrangement pattern of a surface protective film used in an embodiment of the present invention.

Fig. 2C is a schematic plan view showing still another example of a through hole arrangement pattern of the surface protective film used in the embodiment of the present invention.

Fig. 3A is a schematic view showing a method of measuring the roughness of a hole. When the boundary (solid line) of the polarizer 1 and the non-polarized portion 2 is displayed outside the non-polarized portion approximate circle (dotted line), the non-polarized portion and the non-polarized portion are approximately rounded by a distance a.

Fig. 3B is a schematic view showing a method of measuring the roughness of the hole. When the boundary (solid line) between the polarizer 1 and the non-polarized portion 2 is displayed inside the non-polarized portion approximate circle (dotted line), the non-polarized portion and the non-polarized portion are approximately rounded by a distance b.

Form for implementing the invention

Hereinafter, an embodiment of the present invention will be described, but the present invention is not limited to the embodiment.

A. Method of manufacturing polarizing member

The method for producing a polarizing member of the present invention comprises the steps of: transmitting an adhesive layer-layered surface protective film having a thickness of 10 μm or less on one side of the polarizing member, and fabricating a polarized light having an exposed portion exposing at least a portion of the polarizing member on one side thereof. a film laminate; contacting the exposed portion of the polarizing film laminate with an alkaline solution; and removing the surface protection film from the polarizing film laminate. By using the polarizing film laminate having the exposed portion, only a desired portion of the polarizer (that is, a portion exposed by the exposed portion) can be brought into contact with the alkaline solution. By contacting the polarizer with the alkaline solution, the contact portion can be reduced The content of the dichroic substance can thus form a non-polarizing portion having a lower dichroic substance content than other portions.

Further, in the production method of the present invention, a polarizing film laminate in which a layer polarizer and a surface protective film are laminated through an adhesive having a thickness of 10 μm or less is used. By making the thickness of the adhesive layer 10 μm or less, it is possible to prevent bubbles from adhering to the exposed portion by the surface tension of the adhesive. As a result, the alkaline solution sufficiently contacts the entire exposed portion, and the non-polarized portion of a desired shape can be formed with high precision. Further, the polarizing member before forming the non-polarizing portion is strictly an intermediate body of a polarizing member having a non-polarizing portion obtained by the manufacturing method of the present invention, but is merely referred to as a polarizing member in the present specification. As long as the person having ordinary skill in the art has read the description of the present specification, it can be easily understood that the "polarizer" means an intermediate or a polarizing member having a non-polarizing portion which is produced by the manufacturing method of the present invention.

A-1. Production of polarizing film laminate

An adhesive layer-layered surface protective film having a thickness of 10 μm or less is passed through one side of the polarizer to form a polarizing film laminate. The polarizing film laminate used in the present invention has an exposed portion exposing at least a part of the polarizing member on one of the one side faces.

Fig. 1 is a schematic cross-sectional view showing a polarizing film laminate used in an embodiment of the present invention. In this embodiment, a polarizing plate having a structure of a polarizer/protective film is used. In the polarizing film laminate 100, the surface protective film 50 is laminated on the surface of the polarizer 10 of the laminate of the polarizer 10/protective film 20 through the adhesive layer 60 having a thickness of 10 μm or less. The surface protection film 50 has a through hole 71. The polarizing film laminate 100 has a polarizing member exposed through the through hole 71 The exposed portion 51 of 10. The surface protective film 50 is peelably laminated on the polarizing plate (essentially the polarizing member 10). Further, of course, the same procedure can be applied to a polarizing member having a form other than the polarizing plate form (for example, a polarizing member of a single resin film, a laminated body of a resin substrate/polarizer).

In one embodiment, the polarizing film laminate 100 may further laminate another surface protection film (the surface protection film 30 in FIG. 1) on the surface of the surface protective film 50 having the through holes. Hereinafter, the surface protective film 50 having a through hole is also referred to as a first surface protective film, and the surface protective film 30 laminated on the surface of the polarizing film laminate 100 having the through-hole surface protective film is also referred to as a second surface protection. film.

The representative polarizing film laminate has a long strip shape. The long-length polarizing film laminate can be produced, for example, by laminating an elongated surface protective film having a through-hole arranged at a predetermined interval in the longitudinal direction and/or the width direction, and a long polarizing member. By using a long strip of polarizing film laminate, for example, a step of contacting an alkaline solution by immersion and a step of contacting other treatment liquid (for example, a step of contacting an acidic solution) can be carried out. As a result, the productivity of the polarizer can be further improved. Further, the elongated polarizing film laminate may have a plurality of exposed portions. In such a case, the alkaline solution can be sufficiently brought into contact with each of the exposed portions, so that the non-polarized portion of a desired shape can be formed with high precision.

Further, by using the polarizing film laminate, the polarizer having the non-polarizing portion can be obtained by the pattern corresponding to the exposed portion pattern, so that the non-polarizing portion can be precisely controlled and disposed on the entire elongated polarizing member. As a result, the long-length polarizer cuts the predetermined size of the polarized light as the final product. In the case of a piece, the quality variation of each final product can be significantly controlled. Moreover, since such a non-polarized portion is selectively and easily formed at the position of the through hole, a complicated device or operation is not required. Further, according to the present embodiment, the position of the non-polarizing portion can be set in accordance with the size of the polarizing member that is mounted on the image display device as the final product and the position of the camera portion of the image display device, so that the predetermined size can be obtained. The yield of the polarizer is excellent.

A-1-1. Polarizer

The polarizing member is composed of a resin film containing a dichroic substance. The resin film is, for example, a film of a polyvinyl alcohol resin (hereinafter referred to as "PVA resin"). The dichroic substance may be exemplified by iodine or an organic dye. These dichroic substances may be used singly or in combination of two or more. Among them, the use of iodine is preferred. This is because the iodine content can be reduced by contacting the alkaline solution by reducing the iodine complex as described later, and as a result, a non-polarizing portion having characteristics suitable for use as a part of the corresponding camera can be formed.

Any suitable resin may be used as the resin forming the above resin film. It is preferred to use a PVA resin. The PVA-based resin may, for example, be a polyvinyl alcohol or an ethylene-vinyl alcohol copolymer. Polyvinyl alcohol can be obtained by saponifying polyvinyl acetate. The ethylene-vinyl alcohol copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer. The degree of saponification of the PVA-based resin is usually 85 mol% or more and less than 100 mol%, and is preferably 95.0 mol% to 99.95 mol%, and more preferably 99.0 mol% to 99.93 mol%. The degree of saponification can be determined in accordance with JIS K 6726-1994. By using such a saponification degree PVA-based resin, a polarizing member having excellent durability can be obtained. When the degree of saponification is too high, there is a fear of gelation.

The average degree of polymerization of the PVA-based resin can be appropriately selected depending on the purpose. The average degree of polymerization is usually from 1,000 to 10,000, and preferably from 1200 to 4500, and more preferably from 1,500 to 4,300. Further, the average degree of polymerization can be obtained in accordance with JIS K 6726-1994.

The thickness of the polarizing member (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, and more preferably 1 μm or more. If it is such a thickness, the non-polarizing portion can be favorably formed by contacting the alkaline solution. In addition, the time to contact the alkaline solution can be shortened. In addition, there is a case where the thickness of the portion in contact with the alkaline solution is thinner than the other portions. By using a resin film having a small thickness, the difference in thickness between the portion in contact with the alkaline solution and the portion not in contact with the alkaline solution can be reduced, so that adhesion to other constituent elements such as a protective film can be favorably performed.

The resin film is preferably subjected to various treatments such as swelling treatment, stretching treatment, dyeing treatment of the above-described dichroic material, crosslinking treatment, washing treatment, and drying treatment, and has a function as a polarizing member. 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 obtained, for example, by a method of applying a coating liquid containing a material for forming the resin film on a substrate, a method of laminating a resin film on a substrate, or the like.

The dyeing treatment is carried out, for example, by immersing a resin film in a dyeing liquid. The aqueous solution of iodine is preferably used as the dyeing solution. The amount of iodine blended is preferably from 0.04 parts by weight to 5.0 parts by weight relative to 100 parts by weight of water. Since the solubility of iodine to water can be increased, it is desirable to incorporate iodide in an aqueous solution of iodine. Potassium iodide is preferred for the iodide. Iodide blending relative to 100 parts by weight of water The combined amount is preferably from 0.3 part by weight to 15 parts by weight.

In the above extension treatment, the resin film represents a uniaxial extension of from 3 times to 7 times. Further, the extending direction may correspond to the absorption axis direction of the polarizer produced.

A-1-2. Surface protection film

The surface protection film 50 is provided with a through hole 71 corresponding to a portion where the polarizer obtained is not in contact with the alkaline solution (that is, the exposed portion 51 corresponding to the polarizing film laminate).

The shape of the through hole of the surface protective film may be any suitable shape depending on the purpose. Specific examples include a circle, an ellipse, a square, a rectangle, and a diamond. As described above, according to the manufacturing method of the present invention, it is possible to prevent the polarizing member exposed from the exposed portion from being in sufficient contact with the alkaline solution due to the adhesion of the bubble, and thus even a more complicated shape (for example, a star shape) and/or small. The exposed portion of the size may also form a non-polarized portion of a desired shape.

The through hole of the surface protection film can be, for example, a predetermined portion of the surface protective film by mechanical punching (for example, punching, engraving knife punching, plotter, water jet) or removing (for example, laser ablation or chemical dissolution). To form.

The arrangement pattern (pattern formation) of the through holes can be appropriately set depending on the purpose. 2A is a schematic plan view showing an example of a through-hole arrangement pattern of a surface protective film, FIG. 2B is a schematic plan view showing another example of the arrangement pattern of the through holes, and FIG. 2C is a schematic plan view showing still another example of the arrangement pattern of the through holes. For example, as shown in FIG. 2A, the through holes 71 may be disposed at substantially equal intervals along the longitudinal direction and the width direction of the surface protection film 50. In addition, "arranged at substantially equal intervals along the strip direction and the width direction" means a strip direction The intervals are equally spaced, and the intervals in the width direction are equally spaced, and the intervals between the strip directions and the width directions are not necessarily equal. For example, when the interval between the strip directions is L1 and the interval between the width directions is L2, L1=L2 or L1≠L2. Alternatively, the through holes may be arranged at substantially equal intervals along the strip direction, and may be arranged at different intervals in the width direction; they may be arranged at different intervals along the strip direction, and may be arranged at substantially equal intervals in the width direction (all not shown) ). When the through holes are arranged at different intervals in the longitudinal direction or the width direction, the intervals of the adjacent through holes may be all different, or only a part (the interval of the specific adjacent through holes) may be different. Further, a plurality of regions may be defined along the strip direction of the surface protective film, and the intervals of the through holes in the strip direction and/or the width direction may be set in each region.

Further, in one embodiment, the through holes 71 are arranged such that, as shown in FIG. 2A, the straight lines connecting the through holes adjacent in the longitudinal direction are substantially parallel with respect to the strip direction, and are connected in the width direction. The straight lines of the adjacent through holes are substantially parallel with respect to the width direction. In another embodiment, the through holes 71 are disposed such that, as shown in FIG. 2B, the straight lines connecting the through holes adjacent in the longitudinal direction are substantially parallel with respect to the strip direction, and the connections are adjacent in the width direction. The straight line of the through hole has a predetermined angle θ _W with respect to the width direction. In still another embodiment, the through hole 71 is disposed such that, as shown in FIG. 2C, the straight line connecting the through holes adjacent in the longitudinal direction has a predetermined angle θ _L with respect to the longitudinal direction, and is connected in the width direction. The straight line of the adjacent through hole has a predetermined angle θ _W with respect to the width direction. θ _L and/or θ _W should preferably exceed 0° and be less than ±10°. Here, "±" means any direction of clockwise rotation and counterclockwise rotation with respect to the reference direction (length direction or width direction).

The embodiment shown in Figures 2B and 2C has the following advantages. When a long-length polarizing film laminate is used, the non-polarized portion can be formed in a desired pattern (a pattern corresponding to the arrangement pattern of the through holes) while being conveyed by a roll. As a result, the arrangement pattern can be precisely controlled on the entire strip-shaped polarizer to form a non-polarized portion. Here, in order to improve the display characteristics of the image display device, it is sometimes necessary to arrange the absorption axis of the polarizer to be shifted by about 10° with respect to the long side or the short side of the device. Since the absorption axis of the polarizer is in the strip direction or the width direction, by forming a non-polarized portion of the pattern as shown in FIGS. 2B and 2C, in such a case, the entire strip-shaped polarizer can be unified. The positional relationship between the non-polarizing portion and the absorption axis is controlled, so that a final product having excellent axial precision (and therefore excellent optical characteristics) can be obtained. Therefore, the absorption axis direction of the single polarizing member which is cut (for example, cut and punched in the longitudinal direction and/or the width direction) can be precisely controlled at a desired angle, and each polarized light can be remarkably suppressed. The variation of the absorption axis direction of the piece. Further, the arrangement pattern of the through holes is of course not limited to the illustrated example. For example, the through hole 71 may be disposed such that a straight line connecting the through holes adjacent in the longitudinal direction has a predetermined angle θ _L with respect to the longitudinal direction, and a straight line connecting the through holes adjacent in the width direction with respect to the width The directions are substantially parallel. Further, a plurality of regions may be defined along the strip direction of the surface protection film 50, and θ _L and/or θ _{W may be} set in each region.

The surface protective film is preferably a film having a high hardness (for example, a modulus of elasticity). This is because the deformation of the through hole can be prevented, and the through hole can be prevented from being transported and/or adhered particularly when used as a polarizing film laminate having a long strip shape. Deformation. The material for forming the surface protective film may, for example, be an ester resin such as a polyethylene terephthalate resin, a cycloolefin resin such as a norbornene resin, an olefin resin such as polypropylene, or a polyamide resin. A polycarbonate resin, a copolymer resin of the resins, and the like. Among them, an ester resin (particularly a polyethylene terephthalate resin) is preferred. In the case of such a material, the modulus of elasticity is extremely high, and the deformation of the through-hole can be prevented. When the polarizing film laminate is used in the form of a long strip, the through-hole is hardly deformed even when tension is applied during conveyance and/or adhesion. The advantages.

The thickness of the surface protective film can be set to any appropriate value. For example, when used as a polarizing film laminate having a long strip shape, the thickness of the surface protective film is, for example, 30 μm to 150 μm, because the tension is hard to be deformed even when tension is applied during conveyance and/or adhesion.

The surface protective film preferably has an elastic modulus of from 2.2 kN/mm ² to 4.8 kN/mm ² . When the elastic modulus of the surface protective film is within such a range, deformation of the through hole can be prevented, and particularly when used as a polarizing film laminate having a long strip shape, it is difficult to apply a through hole even when a tension is applied during conveyance and/or adhesion. The advantage of deformation. Further, the elastic modulus is measured in accordance with JIS K 6781.

The degree of stretching of the surface protective film is preferably from 90% to 170%. When the degree of stretching of the surface protective film is within such a range, when it is used as a polarizing film laminate having a long strip shape, it has an advantage that it is not easily broken during transportation. Further, the degree of stretching is measured in accordance with JIS K 6781.

A-1-3. Adhesive layer

The thickness of the adhesive layer 60 is 10 μm or less, and preferably 5 μm or less. Make When the polarizing film laminate is used and the alkaline solution is contacted, the bubbles adhere to the surface protective film of the exposed portion, and the alkaline solution may not sufficiently contact the exposed portion. When the size of the exposed portion is small or the shape of the exposed portion is complicated, the influence is remarkable, and there is a fear that a non-polarized portion of a desired shape cannot be formed. By the thickness of the adhesive layer being within such a range, the bubble can be prevented from adhering to the exposed portion by the surface tension of the adhesive. As a result, the alkaline solution can be sufficiently brought into contact with the exposed portion, and a polarizing member having a non-polarizing portion of a desired shape can be obtained.

The adhesive layer can be formed using any suitable composition. The composition for forming an adhesive layer contains, for example, a resin component and any appropriate additives. As the base resin of the adhesive, any appropriate resin may be used, and a resin having a glass transition temperature Tg of 0 ° C or less is preferred. Specifically, an acrylic resin, a rhodium-based resin, or a urethane-based resin can be exemplified. The acrylic resin is preferable because the thickness of the surface protective film and the polarizing member can be favorably maintained even with a thickness of 10 μm or less.

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

The (meth) acrylate having an alkyl group having 1 to 14 carbon atoms may, for example, be methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, or (meth)acrylic acid. Tertiary butyl ester, isobutyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate Ester, n-decyl (meth)acrylate, (methyl) Isodecyl acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-methyl (meth) acrylate Tetraester 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-decyl (meth)acrylate, isodecyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, (methyl) (Meth) acrylate having a C 4 to 14 alkyl group such as n-tridecyl acrylate or n-tetradecyl (meth) acrylate. By including a (meth) acrylate having an alkyl group having 4 to 14 carbon atoms, the adhesion can be easily controlled, and thus the removability is excellent.

The acrylic polymer may contain any suitable other monomer component in addition to the (meth) acrylate having an alkyl group having 1 to 14 carbon atoms. The other monomer component may, for example, be a monomer having a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, a cyano group-containing monomer, a vinyl ester or an aromatic vinyl compound, which can contribute to improvement in cohesive force and heat resistance. Component, carboxyl group-containing monomer, acid anhydride group-containing monomer, hydroxyl group-containing monomer, guanamine-containing monomer, amine group-containing monomer, epoxy group-containing monomer, N-propenyl fluorenylmorpholine, vinyl ether The monomer component having a functional group which acts to increase the adhesion or act as a crosslinking crosslinking point. The other monomer components may be used alone or in combination of two or more.

Examples of the sulfonic acid group-containing monomer include styrenesulfonic acid, allylsulfonic acid, 2-(methyl)acrylamidoxime-2-methylpropanesulfonic acid, and (meth)acrylamide aminesulfonic acid. Sulfopropyl (meth)acrylate, (meth)acryloxynaphthalenesulfonic acid, and the like. Contain The phosphate group monomer is exemplified by 2-hydroxyethyl acryloyl phosphate. The cyano group-containing monomer may be exemplified by acrylonitrile. The vinyl esters may be exemplified by ethyl acetate. The aromatic vinyl compound can be exemplified by styrene.

Examples of the carboxylic acid group-containing monomer include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxyheptyl (meth)acrylate, itaconic acid, maleic acid, and fumaric acid. Crotonic acid, etc. The acid anhydride group-containing monomer may, for example, be maleic anhydride or itaconic anhydride. The hydroxyl group-containing monomer may, for example, be 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, or (meth)acrylic acid- 6-hydroxyhexyl ester, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxydodecyl (meth)acrylate, (4-hydroxymethyl ring) Hexyl)-methacrylate, N-methylol (meth) acrylamide, vinyl alcohol, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monoethylene Ether, etc. The guanamine-containing monomer may, for example, be acrylamide or diethyl acrylamide. The amine group-containing monomer may, for example, be N,N-dimethylamine ethyl (meth)acrylate or N,N-dimethylaminopropyl (meth)acrylate. Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate and allyl epoxypropyl ether. The vinyl ethers can be exemplified by vinyl ether.

For example, from the viewpoint of easy adjustment of the adhesive force, other monomer components can be used, and the obtained polymer has a Tg of 0 ° C or lower. Further, the Tg of the polymer is preferably, for example, -100 ° C or higher.

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

The above acrylic polymer can be obtained by any appropriate polymerization method. For example, solution polymerization, emulsion polymerization, bulk polymerization, suspension A polymerization method generally used as a method of synthesizing an acrylic polymer, such as polymerization.

The adhesive layer-forming composition may contain a resin other than the above-mentioned base resin as a resin component. Other resins may be exemplified by a polyether resin, a modified polyether resin, an epoxy resin, and the like. When other resin is contained, the content ratio of the other resin is preferably 20% by weight or less.

The composition for forming an adhesive layer may contain any appropriate additives in addition to the resin component. For example, a crosslinking agent, a coupling agent, an adhesion imparting agent, a surface lubricant, a leveling agent, a surfactant, an antistatic agent, a slidability improver, a wettability improver, an antioxidant, an anticorrosive agent, and a light stabilizer A powder, a particulate form, a foil, or the like of a solvent, a UV absorber, a polymerization inhibitor, a crosslinking accelerator, a crosslinking catalyst, an inorganic or organic filler, a metal powder, a pigment, or the like.

Any suitable crosslinking agent can be used as the crosslinking agent. An isocyanate compound, an epoxy compound, a hydrazine propane compound, and a melamine compound are mentioned as an example. The crosslinking agent may be used singly or in combination of two or more.

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

The adhesive layer can be formed by any suitable method. Specific examples thereof include a method in which a composition for forming an adhesive is applied onto the surface protective film and dried, a method in which an adhesive layer is formed on the separator, and the adhesive layer is transferred onto the surface protective film. The coating method may, for example, be a roll coating method such as reverse coating or gravure coating, a spin coating method, a screen coating method, a jet knife coating method, a dip coating method, or a spray coating method.

In one embodiment, the first surface protective film is an adhesive sheet having an adhesive layer having a thickness of 10 μm or less. The first surface protection film of the embodiment has a laminate of a resin film used as the surface protection film and an adhesive layer provided on one surface of the resin film, and has a through hole penetrating the resin film and the adhesive layer. . When the first surface protective film is an adhesive sheet, the long polarizing member and the long first surface protective film can be adhered by a roll-to-roll method, so that the manufacturing efficiency can be further improved. In this embodiment, the separator is temporarily adhered to the adhesive.

The separator has a function as a protective material for protecting the adhesive layer until it is actually used. The separator may be, for example, a plastic coated with a surface-coated release agent such as a silicone-based release agent, a fluorine-based release agent, or a long-chain alkyl acrylate release agent (for example, polyethylene terephthalate (PET). ), polyethylene, polypropylene) film, non-woven fabric or paper. The thickness of the separator may be any suitable thickness depending on the purpose. The thickness of the separator is, for example, 10 μm to 100 μm. The separator may be laminated on the laminate of the resin film and the adhesive layer used as the surface protective film, or an adhesive layer may be formed on the separator and a laminated layer of the separator and the adhesive layer may be used as the surface protective film. Used on the resin film.

As described above, the polarizing film laminate 100 may further laminate the second surface protection film 30 on the side where the first surface protection film 50 is not disposed. As the second surface protection film, a film similar to the first surface protection film 50 can be used except that no through hole is provided. In addition, the second surface protection film may also be soft such as a polyolefin (for example, polyethylene) film (example) For example, a film with a low modulus of elasticity. By using the second surface protective film, the polarizing plate (polarizer/protective film) can be further suitably protected in the step of contacting with the alkaline solution, and as a result, the step of contacting the polarizing member with the alkaline solution can be performed more satisfactorily.

A-2. Steps of contacting with an alkaline solution

Next, the alkaline solution is brought into contact with the exposed portion of the polarizing film laminate. By contacting the alkaline solution, the content of the dichroic substance in the exposed portion can be reduced, so that the non-polarizing portion can be formed by reducing the content of the dichroic substance. Further, the polarizing member used for the polarizing film laminate is preferably a polarizing member containing iodine as described above. When the polarizer contains iodine as a dichroic substance, the iodine content of the exposed portion can be reduced by contacting the exposed portion of the polarizer and the alkaline solution, and as a result, the non-polarized portion can be selectively formed only in the exposed portion. Therefore, the non-polarizing portion can be selectively formed in a predetermined portion of the polarizing member without a complicated operation with a very high manufacturing efficiency. Further, when iodine remains in the polarizer, even if the iodine complex is destroyed to form the non-polarized portion, the iodine complex is formed again with the use of the polarizer, and the non-polarized portion may have no desired characteristics. In the present invention, iodine itself may be removed by a polarizing member (substantially a non-polarizing portion). As a result, the characteristics of the non-polarizing portion can be prevented from changing with the use of the polarizing member.

The step of bringing the alkaline solution into contact with the polarizing film laminate may employ any appropriate means. For example, immersion, dripping, coating, spraying, etc. are mentioned. As described above, by using the first surface protective film (and, if necessary, the second surface protective film), the iodine content of the polarizing member can be reduced in portions other than the exposed portion of the polarizing film laminate, and therefore, by impregnation only A non-polarizing portion is formed in a desired portion. Specifically, by using a polarizing film laminate It is immersed in an alkaline solution, and only the exposed portion in the polarizing film laminate is in contact with the alkaline solution.

The non-polarizing portion is formed by an alkaline solution in more detail below. After coming into contact with the exposed portion of the polarizing film laminate, the alkaline solution penetrates into the exposed portion (specifically, the polarizer). The iodine complex contained in the polarizer is reduced by the alkali contained in the alkaline solution to become iodine. When the iodine complex is reduced to iodide 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. Further, by reducing the iodine complex, the transmittance of the exposed portion can be improved. The iodine which becomes an iodide ion moves from the exposed part to the solvent of the alkaline solution. As a result, the iodide ions are removed from the polarizer together with the alkaline solution. In this manner, the non-polarizing portion can be selectively formed in a predetermined portion of the polarizing member, and the non-polarizing portion can be changed and stabilized without passing through time. In addition, by adjusting the material, thickness and mechanical properties of the first surface protective film, the concentration of the alkaline solution, and the immersion time of the polarizing film laminate in the alkaline solution, the alkaline solution can be prevented from impregnating into the undesired portion. (As a result, a non-polarized portion is formed in an undesired portion).

Any basic compound may be used as the basic compound contained in the above alkaline solution. Examples of the basic compound include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide; inorganic alkali metal salts such as sodium carbonate; and organic sodium acetate. Alkali metal salt, ammonia water, and the like. The alkaline compound contained in the alkaline solution is preferably an alkali metal hydroxide, and sodium hydroxide, potassium hydroxide or lithium hydroxide is more preferable. By using an alkaline solution containing an alkali metal hydroxide, the iodine complex can be efficiently ionized, so that the non-polarized portion can be formed more easily. The alkali The compound may be used alone or in combination of two or more.

As the solvent of the above alkaline solution, any appropriate solvent can be used. Specific examples thereof include alcohols such as water, ethanol, and methanol, ethers, benzene, chloroform, and a mixed solvent of the solvents. The iodide ion can be well moved into the solvent, and the iodide ion can be easily removed. The solvent is preferably water or alcohol.

The concentration of the above alkaline solution is, for example, 0.01 N to 5 N, and preferably 0.05 N to 3 N, and more preferably 0.1 N to 2.5 N. When the concentration of the alkaline solution is within such a range, the iodine content inside the polarizer can be efficiently reduced, and the iodine complex can be prevented from being ionized in a portion other than the exposed portion.

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

After the alkaline solution is brought into contact with the exposed portion of the polarizer (after forming the non-polarized portion), it may be removed by any appropriate means as needed. Specific examples of the method for removing the alkaline solution include, for example, wiping off with a rag, suction removal, natural drying, heat drying, air drying, reduced pressure drying, washing, and the like. The drying temperature at which the alkaline solution is removed by drying is, for example, 20 ° C to 100 ° C.

A-3. Step of removing the surface protective film

After the necessary steps are performed, the surface protective film can be removed from the polarizing film laminate. As described above, the surface protective film is peelably adhered to the surface of the polarizing member through the adhesive layer. Therefore, the production of the non-polarized portion is biased.

After the steps required for the light member, the surface of the polarizer can be easily removed.

A-4. Other steps

The method for producing a non-polarizing portion having a non-polarizing portion according to the present invention may further include a step of forming a polarizing film laminate, a step of bringing the exposed portion of the polarizing film laminate into contact with the alkaline solution, and a step of removing the surface protective film. Any appropriate steps. Other steps may be exemplified by a step of contacting with an acidic solution and a washing step.

A-4-1. Steps of contacting with acidic solution

The production method of the present invention may further comprise a step of bringing the exposed portion of the polarizing film laminate into contact with the acidic solution. By further including the step of contacting with the acidic solution, the non-polarized portion of the desired size and shape can be more stably maintained (especially in a humidified environment). The step of contacting the acidic solution can be carried out, for example, after the step of contacting with the alkaline solution.

Any acidic compound may be used as the acidic compound contained in the acidic solution. Examples of the acidic compound include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, hydrogen fluoride, and boric acid, organic acids such as formic acid, oxalic acid, citric acid, acetic acid, and benzoic acid. The concentration of the acidic solution is, for example, 0.01 N to 5 N, and preferably 0.05 N to 3 N, and more preferably 0.1 N to 2.5 N.

The solvent used for the acidic solution, the liquid temperature of the acidic solution, the time of contact with the acidic solution, and the contact method may be the same as those which can be employed in the step of contacting the alkaline solution described in the above item A-2.

The step of contacting with the acidic solution is preferably carried out before the peeling step of the above surface protective film (specifically, in the state of the polarizing film laminate). It can be contacted with an alkaline solution by being carried out in a state of a polarizing film laminate The step of continuously performing the step of contacting with the acidic solution.

A-4-2. Washing step

The manufacturing method of the present invention may further comprise a washing step. The washing step can be carried out only once or for most times. The cleaning step can be carried out at any appropriate stage of the manufacturing steps of the polarizer having the non-polarizing portion. For example, after the polarizing member that is in contact with the alkaline solution is washed with any appropriate liquid, the step of contacting with the acidic solution may be performed, or the step of contacting with the alkaline solution and the step of contacting with the acidic solution may be performed. A washing step for a suitable liquid.

Any suitable liquid can be used for the liquid to be used for washing. For example, an alcohol such as pure water, methanol or ethanol, an acidic aqueous solution, and a mixed solvent of the liquids may be mentioned. Further, the temperature of the liquid to be used may be set to any appropriate temperature.

B. Polarizer with non-polarizing portion

The polarizing member obtained by the method of the present invention may have a non-polarizing portion of a desired shape and size formed with high precision. Therefore, the polarizing member of the present invention can have excellent performance and design.

A polarizer having a non-polarizing portion can be used, for example, for an image display device having a camera. This is because even if a non-polarized portion having a smaller size is formed, the camera can sufficiently exhibit the camera function, and the appearance of the obtained image display device is also good.

The planar shape of the non-polarizing portion may be any appropriate shape as long as it does not adversely affect the camera performance of the image display device. In addition, the transmittance of the non-polarizing portion (for example, measured at 23 ° C with a wavelength of 550 nm light) The transmittance is preferably 50% or more, more preferably 60% or more, more preferably 75% or more, and more preferably 90% or more. With such a transmittance, the desired transparency as a non-polarized portion can be ensured. As a result, when the polarizer is disposed so that the non-polarizing portion corresponds to the camera portion of the video display device, it is possible to prevent adverse effects on the imaging performance of the camera.

The non-polarizing portion is a portion having a smaller content of the dichroic material than the other portion of the polarizing member (the portion having the polarizing property). The content of the dichroic substance contained in the non-polarizing portion is preferably 1.0% by weight or less, more preferably 0.5% by weight or less, and still more preferably 0.2% by weight or less. Further, the lower limit of the dichroic substance content of the non-polarized portion is usually below the detection limit value. When the content of the dichroic substance in the non-polarizing portion is within such a range, not only the desired transparency of the non-polarizing portion but also the brightness and the hue when the non-polarizing portion is used as the portion corresponding to the camera of the image display device is used. From the point of view, very good photographic performance can also be achieved. Further, when iodine is used as the dichroic substance, the iodine content of the non-polarized portion is a value obtained by using a calibration curve prepared in advance by a standard sample by the X-ray intensity measured by fluorescent X-ray analysis.

The difference between the content of the dichroic substance contained in the portion other than the non-polarizing portion of the polarizer (the portion having the polarizing performance) and the content of the dichroic material contained in the non-polarizing portion is preferably 0.5% by weight or more, and more preferably 1% by weight or more. . The difference between the content of the dichroic substance contained in the portion other than the non-polarizing portion and the content of the dichroic substance contained in the non-polarizing portion is within such a range, and the non-polarizing portion may have sufficient transparency, and for example, it may be preferably used. The non-polarized portion serves as a camera portion corresponding to the image display.

C. Polarizer

Practically, a polarizing member can be provided as a polarizing plate. The polarizing plate has a polarizing member and a protective film disposed on at least one side of the polarizing member. Practically, the polarizing plate has an adhesive layer as the outermost layer. The representative adhesive layer becomes the outermost layer on the side of the image display device. The separator is temporarily peeled off on the adhesive layer.

The material for forming the protective film may, for example, be a cellulose resin such as diethyl ketone cellulose or triacetyl cellulose, an olefin resin such as a (meth)acrylic resin, a cycloolefin resin or polypropylene, or a poly pair. An ester resin such as an ethylene phthalate resin, a polyamide resin, a polycarbonate resin, or a copolymer resin of the resins. The thickness of the protective film is preferably from 10 μm to 100 μm. The protective film represented by the laminate is laminated on the polarizer through an adhesive layer (specifically, an adhesive layer, an adhesive layer). The representative adhesive layer is formed of a PVA-based adhesive or an activated energy beam hardening type adhesive. The representative adhesive layer is formed of an acrylic adhesive.

The polarizing plate may further have any suitable 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. Further, the protective film may have an optical compensation function (specifically, an appropriate refractive index ellipsoid, an in-plane phase difference, and a thickness direction phase difference may be used depending on the purpose).

The surface treatment layer may be disposed on the viewing side of the polarizing plate. Representative examples of the surface treatment layer include a rod coating layer, an antireflection layer, and an antiglare layer.

D. Image display device

The image display device of the present invention has the above polarizer. The image display device can be exemplified by a liquid crystal display device and an organic EL device. Specifically, liquid crystal The display device has a liquid crystal panel, and the liquid crystal panel includes a liquid crystal cell and the polarizing member disposed on one side or both sides of the liquid crystal cell. The organic EL device has an organic EL panel in which the above-described polarizer is disposed on the viewing side. The polarizer may be disposed such that the non-polarized portion corresponds to the camera portion of the mounted image display device.

Example

Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited to the examples.

[Manufacturing Example 1] Production of Surface Protective Film 1 with Adhesive Layer

100 parts by weight of an acrylic resin (acrylic polymer having a weight average molecular weight of 600,000 formed from a composition ratio of butyl acrylate/acrylic acid = 95/5) and 5 parts by weight of an epoxy crosslinking agent (MITSUBISH GAS CHEMICAL) (Stock), trade name: TETRAD-C), modulating the acrylic adhesive 1.

The obtained acrylic adhesive was applied to a PET film (manufactured by MITSUBISH CHEMICAL POLYESTER FILM, trade name: Diafoil T100C) having a thickness of 38 μm (width: 1200 mm, length: 43 m) to a thickness of 10 μm after drying. Forming an adhesive layer. The separator is adhered to the formed adhesive layer to form an adhesive sheet. On the obtained adhesive sheet, 1000 circular holes having a diameter of 2 mm were formed using a sharp knife (Pinnacle Knife). Each of the small holes was formed at intervals of 250 mm in length and 400 mm in width to obtain a surface protective film 1 having an adhesive layer.

[Manufacturing Example 2] The surface protective film 2 having an adhesive layer was produced. Make

A surface protective film 2 having an adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the adhesive layer was 5 μm.

[Production Example 3] Production of surface protective film C1 having an adhesive layer

A surface protective film C1 having an adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the adhesive layer was 30 μm.

[Production Example 4] Production of surface protective film C2 having an adhesive layer

A surface protective film C2 having an adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the adhesive layer was 20 μm.

[Manufacturing Example 5] Production of Surface Protective Film C3 with Adhesive Layer

A surface protective film C3 having an adhesive layer was obtained in the same manner as in Production Example 1 except that the thickness of the adhesive layer was 15 μm.

[Manufacturing Example 6] Production of Surface Protective Film 3 with Adhesive Layer

100 parts by weight of an acrylic resin (acrylic polymer having a weight average molecular weight of 500,000 formed from a composition ratio of 2-ethylhexyl acrylate/2-hydroxyethyl acrylate = 96/4) and 4 parts by weight of isocyanate A binder (manufactured by NIPPON POLYURETHANE INDUSTRY, trade name: CORONATE HX) was used to prepare an acrylic adhesive 2.

The obtained propylene was coated on a PET film (manufactured by Toyobo Co., Ltd., trade name: E5000) having a thickness of 38 μm (width: 1200 mm, length: 43 m). The acid-based adhesive was dried to a thickness of 10 μm to form an adhesive layer. The separator is adhered to the formed adhesive layer to form an adhesive sheet. On the obtained adhesive sheet, 1000 circular holes having a diameter of 2 mm were formed using a sharp knife. Each of the small holes was formed at intervals of 250 mm in length and 400 mm in width, and a surface protective film 3 having an adhesive layer was obtained.

[Manufacturing Example 7] Production of Surface Protective Film 4 with Adhesive Layer

A surface protective film 4 having an adhesive layer was produced in the same manner as in Production Example 6, except that the thickness of the adhesive layer was 5 μm.

[Production Example 8] Production of surface protective film C4 having an adhesive layer

A surface protective film C4 having an adhesive layer was obtained in the same manner as in Production Example 6, except that the thickness of the adhesive layer was 30 μm.

[Manufacturing Example 9] Production of Surface Protective Film C5 with Adhesive Layer

A surface protective film C5 having an adhesive layer was obtained in the same manner as in Production Example 6, except that the thickness of the adhesive layer was 20 μm.

[Manufacturing Example 10] Production of Surface Protective Film C6 with Adhesive Layer

A surface protective film C6 having an adhesive layer was obtained in the same manner as in Production Example 6, except that the thickness of the adhesive layer was 15 μm.

[Production Example 11] Production of surface protective film 5 having an adhesive layer

In addition to making the diameter of the small hole formed on the adhesive sheet 4 mm, In the same manner as in Example 1, a surface protective film 5 having an adhesive layer was obtained.

[Manufacturing Example 12] Production of Surface Protective Film 6 with Adhesive Layer

A surface protective film 6 having an adhesive layer was produced in the same manner as in Production Example 2 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Production Example 13] Production of surface protective film C7 having an adhesive layer

A surface protective film C7 having an adhesive layer was obtained in the same manner as in Production Example 3 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Production Example 14] Production of surface protective film C8 having an adhesive layer

A surface protective film C8 having an adhesive layer was obtained in the same manner as in Production Example 4 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Production Example 15] Production of surface protective film C9 having an adhesive layer

A surface protective film C9 having an adhesive layer was obtained in the same manner as in Production Example 5 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Manufacturing Example 16] Production of Surface Protective Film 7 with Adhesive Layer

A surface protective film 7 having an adhesive layer was produced in the same manner as in Production Example 6, except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Manufacturing Example 17] Production of Surface Protective Film 8 with Adhesive Layer

In addition to making the diameter of the small hole formed on the adhesive sheet 4 mm, In the same manner as in Example 7, a surface protective film 8 having an adhesive layer was obtained.

[Manufacturing Example 18] Production of Surface Protective Film C10 with Adhesive Layer

A surface protective film C10 having an adhesive layer was produced in the same manner as in Production Example 8 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Production Example 19] Production of surface protective film C11 having an adhesive layer

A surface protective film C11 having an adhesive layer was obtained in the same manner as in Production Example 9 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

[Production Example 20] Production of surface protective film C12 having an adhesive layer

A surface protective film C12 having an adhesive layer was obtained in the same manner as in Production Example 10 except that the diameter of the small holes formed in the adhesive sheet was 4 mm.

<Example 1>

An amorphous isophthalic acid copolymerized polyethylene terephthalate (IPA copolymerized PET) film (thickness: 100 μm) having a long strip shape, a water absorption ratio of 0.75%, and a Tg of 75 ° C was used as a substrate. Corona treatment was carried out on one side of the substrate, and coating and drying at 25 ° C on the corona-treated surface contained polyvinyl alcohol (degree of polymerization 4200, degree of saponification 99.2 mol%) at a ratio of 9:1. And an aqueous solution of PVA (polymerization degree 1200, acetylation degree 4.6%, saponification degree 99.0 mol% or more, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "GOHSEFIMER Z200"), A PVA-based resin layer having a thickness of 11 μm was formed to form a laminate.

The resulting laminate is placed in an oven at 120 ° C between rolls with different peripheral speeds The free end uniaxially extends to 2.0 times in the longitudinal direction (longitudinal direction) (auxiliary extension in air).

Next, the laminate was immersed in an insolubilizing bath (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 polarizing plate was immersed in a dye bath having a liquid temperature of 30 ° C to have a predetermined transmittance. In the present embodiment, it was immersed in an aqueous iodine solution prepared by blending 0.2 part by weight of iodine with respect to 100 parts by weight of water and blending 1.5 parts by weight of potassium iodide for 60 seconds (dyeing treatment).

Next, immersed in a cross-linking bath at a liquid temperature of 30 ° C (with respect to 100 parts by weight of water, blending 3 parts by weight of potassium iodide and blending 3 parts by weight of boric acid to prepare an aqueous solution of boric acid) for 30 seconds. Joint processing).

Then, one side of the laminate was immersed in an aqueous solution of boric acid at a liquid temperature of 70 ° C (an aqueous solution obtained by blending 4 parts by weight of boric acid with 5 parts by weight of potassium iodide with respect to 100 parts by weight of water). Uniaxial stretching is performed in the longitudinal direction (longitudinal direction) between rolls having different circumferential speeds so that the total stretching ratio is 5.5 times (water extension).

Then, the laminate was immersed in a washing bath at a liquid temperature of 30 ° C (an aqueous solution obtained by blending 4 parts by weight of potassium iodide with respect to 100 parts by weight of water) (washing treatment).

Next, a PVA-based resin aqueous solution (manufactured by Nippon Synthetic Chemical Co., Ltd., trade name "GOHSEFIMER (registered trademark) Z-200", and a resin concentration of 3 weights were applied to the surface of the PVA-based resin layer of the laminate. %) and a protective film (thickness 25 μm) was adhered, followed by heating in an oven maintained at 60 ° C for 5 minutes. Then, the substrate was peeled off from the PVA-based resin layer to obtain a polarizing plate (width: 1200 mm, length: 43 m) having a polarizing plate having a transmittance of 42.3% and a thickness of 5 μm.

Next, on the side surface of the polarizer of the obtained polarizing plate, the surface protective film 1 having the adhesive layer peeled off from the separator was adhered through the adhesive layer to obtain a laminate. The obtained laminates were each immersed in an alkaline solution (aqueous sodium hydroxide solution, 1 mol/L (1 N)) at room temperature for 8 seconds, and 0.1 mol/L (0.1 N) hydrochloric acid for 30 seconds. Then, it was dried at 60 ° C, and the PET film was peeled off to obtain a polarizing plate comprising a polarizing member having a transparent portion.

[Examples 2 to 8]

A polarizing plate including a polarizing member having a transparent portion was produced in the same manner as in Example 1 except that the surface protective film having an adhesive layer described in Table 1 was used.

(Comparative Examples 1 to 12)

A polarizing plate including a polarizing member having a transparent portion was produced in the same manner as in Example 1 except that the surface protective film having an adhesive layer described in Table 1 was used.

The transmittance and the iodine content of the transparent portion of the polarizer formed in each of the examples and the comparative examples were measured by the following methods.

1. Transmittance (Ts)

It was measured using a spectrophotometer (Murako Color Technology Research Institute Co., Ltd., product name "DOT-3"). The transmittance (T) is a Y value after visual sensitivity correction by a 2 degree field of view (C light source) of JIS Z 8701-1982.

2. Iodine content

The iodine content of the transparent portion of the polarizing member was determined by fluorescent X-ray analysis. Specifically, the iodine content of the polarizing member was determined from the X-ray intensity measured by the following conditions by using a calibration curve prepared in advance using a standard sample.

Analytical device: XSX100e, a fluorescent X-ray analyzer (XRF) manufactured by Rigaku Electric Industrial Co., Ltd.

For the cathode: 铑

Spectroscopic crystallization: lithium fluoride

Excitation light energy: 40kV-90mA

Iodine measurement line: I-LA

Quantitative method: FP method

2θ angle peak: 103.078deg (iodine)

Measurement time: 40 seconds

The transparent portions of the polarizers produced in the respective Examples and Comparative Examples all had a transmittance of 90% or more and an iodine content of less than 1% by weight. The transparent portions may have functions as non-polarizing portions.

[Evaluation method]

The degree of shape integration of each of the transparent portions formed on the polarizing plate was measured by the following method. In the 1000 transparent portions on the polarizer, the ratio of the degree of shape integration of more than 0.05 is 40% or less, ◎, 50% or less is ○, and more than 60% is ×. The results are shown in Table 1.

[shape integration]

The ultrahigh-speed flexible image display system (manufactured by KEYENCE Co., Ltd., trade name: XG7700) was used to carry out the preparations of Examples 1 to 8 and Comparative Examples 1 to 12. The non-polarized portion edge of the polarizer is detected, and the non-polarized portion is approximated to be round. The distance between the circumference of the non-polarized portion approximate circle (the broken line portion of FIGS. 3A and 3B) and the boundary between the polarizer 1 and the non-polarized portion 2 (the solid line portion of FIGS. 3A and 3B) is measured every 2°, and the total is obtained. 180 points distance. In the case of the measurement point, when the boundary between the polarizer 1 and the non-polarizing portion 2 is located outside the approximate circle of the non-polarizing portion (that is, in the case of FIG. 3A), the distance a between the non-polarizing portion 2 and the non-polarizing portion is measured, and When the boundary between the polarizer 1 and the non-polarizing portion 2 is located inside the non-polarizing portion approximate circle (that is, in the case of FIG. 3B), the distance b between the non-polarizing portion 2 and the non-polarizing portion is measured. The sum value of the maximum value of the distance a and the maximum value of the distance b is calculated as the hole roughness. Calculated pore roughness values except for the pore diameter formed on 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 12:4mm), find the value of shape integration.

In Examples 1 to 8 using a polarizing film laminate having a thickness of the adhesive layer of 10 μm or less, a polarizing member having a non-polarizing portion corresponding to the shape of a small hole formed on the PET film was produced in high yield. In the case of the polarizer having such a non-polarizing portion, for example, when the non-polarizing portion is used corresponding to the portion of the camera portion of the image display device, the alignment workability can be improved, so that the alignment of the camera can be satisfactorily performed. Even in Examples 1 to 4 provided in the small pores of the surface protective film as small as 2 mm, a polarizing member having a non-polarizing portion close to the shape of a small hole formed on the PET film can be obtained.

Industrial availability

The polarizing member obtained by the method of the present invention can be applied to wisdom A video display device (liquid crystal display device, organic EL device) having a camera such as a mobile phone such as a mobile phone, a notebook PC, or a tablet PC.

10‧‧‧ polarizer

20‧‧‧Protective film

30,50‧‧‧Surface protection film

51‧‧‧Exposed Department

60‧‧‧Adhesive layer

71‧‧‧through holes

100‧‧‧Polarized film laminate

Claims (10)

A manufacturing method of a polarizing member having a non-polarizing portion, comprising the steps of: transmitting an adhesive layering surface protective film having a thickness of 10 μm or less on one side of a polarizing member, and forming at least one portion of the polarizing member on one side thereof a polarizing film laminate of the exposed portion; contacting the exposed portion of the polarizing film laminate with an alkaline solution; and removing the surface protective film from the polarizing film laminate. The method of producing a polarizing member according to claim 1, wherein the step of contacting the exposed portion with the alkaline solution comprises immersing the polarizing film layered body in an alkaline solution. The method of producing a polarizing member according to claim 1 or 2, wherein the adhesive layer contains an acrylic resin. The method of producing a polarizing member according to any one of claims 1 to 3, further comprising the step of contacting the exposed portion of the polarizing film laminate with an acidic solution. The method of producing a polarizing member according to claim 4, wherein the step of contacting the exposed portion with the acidic solution comprises immersing the polarizing film layered body in an acidic solution. The method for producing a polarizing member according to claim 5, wherein the step of contacting the exposed portion with the alkaline solution comprises immersing the polarizing film layered body in an alkaline solution, and the step of contacting the exposed portion with the acidic solution comprises The polarizing film laminate is immersed in an acidic solution. The method of producing a polarizing member according to any one of claims 1 to 6, wherein the polarizing film laminate is elongated. A polarizing member is produced by the method of any one of claims 1 to 7. A polarizing plate having the polarizing member of claim 8. An image display device having the polarizing plate of claim 9.