JP6514464B2 - Method of manufacturing polarizer having non-polarization part - Google Patents

Description

  The present invention relates to a method of manufacturing a polarizer having a nonpolarizing portion.

  Some image display devices such as mobile phones and laptop personal computers (PCs) are equipped with internal electronic components such as a camera. Various studies have been made for the purpose of improving the camera performance and the like of such image display devices (for example, Patent Documents 1 to 6). However, with the rapid spread of smartphones and touch panel information processing apparatuses, further improvement of camera performance and the like is desired. Moreover, in order to cope with diversification and high functionalization of the shape of an image display apparatus, the polarizing plate which has a polarization performance in part is calculated | required. Where it is desired to manufacture an image display device and / or its parts at an acceptable cost in order to realize these needs industrially and commercially, various considerations are required to establish such a technology. Matters are left.

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

  The present invention has been made to solve the above-described conventional problems, and the main object thereof is excellent even when wet processing is performed using a polarizing film laminate having an exposed portion in which a polarizer is exposed. It is an object of the present invention to provide a method of manufacturing a polarizer capable of providing a polarizer having a different appearance.

The method for producing a polarizer having a nonpolarizing part of the present invention comprises a polarizer and a surface protective film disposed on one side of the polarizer, and has an exposed part on the one side of which the polarizer is exposed. The process of carrying out the wet process of the polarizing film laminated body, The process of removing the process liquid used by this wet process adhering to this polarizing film laminated body surface, The process of removing this process liquid can follow an exposed part It is carried out by bringing the processing liquid removing member made of a material and the polarizing film laminate into contact from the surface protective film side of the polarizing film laminate.
In one embodiment, the treatment liquid removing member is at least one selected from the group consisting of a rag, cloth, sponge, chamomile towel, and chamomile skin.
In one embodiment, in the step of removing the treatment liquid, the member for treatment liquid removal and the polarizing film laminate are brought into contact by applying a pressure of 0.1 kPa to 500 kPa.
In one embodiment, the step of removing the treatment liquid is performed by the treatment liquid removing member attached to a rotating body.
In one embodiment, the method for producing a polarizer having a non-polarization part according to the present invention comprises alkali treatment with a basic solution as the wet treatment, wet treatment using an acid treatment basic solution with an acidic solution, and washing And at least one selected from the group consisting of:

  A polarizer and a surface protection film disposed on one side of the polarizer for the purpose of performing wet processing only on a desired portion, and a polarizing film laminate having an exposed portion on the one side of which the polarizer is exposed Wet treatment may be performed using the body. In this polarizing film laminated body, an unevenness | corrugation arises between the surface protection film side surface and an exposure part. Therefore, the treatment liquid used in the wet treatment may remain in the exposed portion. Usually, after the wet treatment, a step of removing the treatment liquid is provided. However, when using the polarizing film laminated body which has an exposed part, the process liquid which remained in the exposed part may not fully be removed. The remaining treatment liquid may become traces of water by drying, which may impair the appearance of the obtained polarizer. In addition, when the surface protection film is peeled off with the treatment liquid remaining in the exposed part, the treatment liquid may adhere to the untreated part, and the property may be adversely affected particularly at the boundary between the exposed part and the other part. .

  According to the manufacturing method of the present invention, it is provided with a polarizer and a surface protection film disposed on one surface side of the polarizer, and using a polarizing film laminate having an exposed part on the one surface side of which the polarizer is exposed. Even when wet processing is performed, a polarizer having an excellent appearance can be provided. The manufacturing method of the present invention is a process comprising a material capable of following the exposed portion in the step of wet-treating the polarizing film laminate and removing the treatment liquid used in the wet treatment adhering to the surface of the polarizing film laminate. The member for liquid removal and the polarizing film laminate are brought into contact from the surface protective film side of the polarizing film laminate. The treatment liquid removing member enters the exposed portion by bringing the treatment liquid removing member made of a material capable of following the exposed portion into contact with the polarizing film laminate from the surface protective film side of the polarizing film laminate. It also becomes possible to remove the treatment liquid remaining in the exposed part of the polarizing film laminate. This makes it possible to provide a polarizer excellent in appearance. In addition, since the treatment liquid remaining in the exposed portion can be prevented from flowing out to a portion not subjected to wet treatment as the surface protection film is peeled off from the polarizing film laminate, the untreated portion, particularly the boundary An adverse effect on the properties of the part can also be prevented.

It is a schematic sectional drawing of the polarizing film laminated body used by one embodiment of this invention. It is a schematic sectional drawing of the surface protection film used in one embodiment of this invention. It is a schematic perspective view of the surface protection film by one embodiment of the present invention. It is a schematic perspective view explaining pasting of a surface protection film and a polarizing plate in a manufacturing method of light polarizer using a surface protection film by one embodiment of the present invention. FIG. 5 is a schematic view showing a process liquid removing process performed by one embodiment of the present invention. It is the schematic which shows the process liquid removal process performed by other embodiment of this invention.

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

  The method for producing a polarizer having a nonpolarizing part of the present invention comprises a polarizer and a surface protective film disposed on one side of the polarizer, and has an exposed part on the one side of which the polarizer is exposed. The process of wet-processing a polarizing film laminated body, The process of removing the process liquid used by this wet process adhering to this polarizing film laminated body surface (henceforth a process liquid removal process) are included. In the production method of the present invention, the treatment liquid removing member composed of a material capable of following the treatment liquid in the step of removing the treatment liquid, and the polarizing film laminate are the surface protection film side of the polarizing film laminate. It is done by contacting from. As a result, the treatment liquid removing member enters the exposed portion, and the treatment liquid remaining on the exposed portion of the polarizing film laminate can be removed in the treatment liquid removing step, and a polarizer excellent in appearance is provided. Can. In addition, since the treatment liquid remaining in the exposed portion can be prevented from flowing out to a portion not subjected to wet treatment as the surface protection film is peeled off from the polarizing film laminate, the untreated portion, particularly the boundary An adverse effect on the properties of the part can also be prevented. In addition, although the polarizer before forming a non-polarization part is an intermediate 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. Those skilled in the art will easily understand, from the description herein, whether "polarizer" means an intermediate or a polarizer having a non-polarizing portion obtained by the production method of the present invention. be able to.

A. Process for producing a polarizing film laminate The method for producing a polarizer of the present invention comprises a polarizer and a surface protective film disposed on one side of the polarizer, and an exposed portion in which the polarizer is exposed on the one side Wet processing is performed using the polarizing film laminated body which has these. Since this polarizing film laminate has an exposed portion where the polarizer is exposed, only the exposed portion of the polarizer is subjected to the wet processing in the wet processing.

  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, when wet processing is performed on the surface of the polarizer 10 of the laminate of the polarizer 10 / protective film 20, a surface protective film 50 for protecting a portion not to be subjected to wet treatment is laminated. The surface protective film 50 has through holes 61 arranged at predetermined intervals (that is, in a predetermined pattern) in the longitudinal direction and / or the width direction. The polarizing film laminate 100 has an exposed portion 51 in which the polarizer 10 is exposed from the through hole 61. The surface protective film 50 is peelably laminated to the polarizing plate (substantially, the polarizer 10) via any appropriate adhesive. It is needless to say that the same procedure can be applied to a polarizer (for example, a polarizer which is a single resin film, a laminate of a resin base material / a polarizer) having a form other than the form of the polarizing plate.

  Moreover, in this embodiment, another surface protective film 30 is laminated on the protective film 20 of the polarizing plate. Hereinafter, the surface protection film 30 having a through hole is referred to as a first surface protection film, and the surface protection film 30 laminated on the side of the polarizing film laminate 100 on which the surface protection film having a through hole is not laminated is referred to as a second surface. It is also called a protective film.

  FIG. 2 is a schematic cross-sectional view of a surface protective film used in one embodiment of the present invention. The surface protective film 50 has a resin film 70 and an adhesive layer 80 provided on one side of the resin film 70. The surface protective film 50 has through holes 61 penetrating the resin film 70 and the pressure-sensitive adhesive layer 80, which are disposed at predetermined intervals (that is, in a predetermined pattern) in the longitudinal direction and / or the width direction. The arrangement pattern of the through holes 61 can be appropriately set according to the purpose. FIG. 3 is a schematic perspective view of a surface protection film according to one embodiment of the present invention. For example, as shown in FIG. 3, the through holes 61 can be arranged at substantially equal intervals in both the longitudinal direction and the width direction. Note that "substantially equally spaced in any of the longitudinal direction and the width direction" means that the intervals in the longitudinal direction are equal intervals, and the intervals in the width direction are equal intervals. It is not necessary for the distance in the longitudinal direction to be equal to the distance in the width direction. For example, when an interval in the longitudinal direction is L1 and an interval in the width direction is L2, L1 = L2 may be satisfied, or L1 ≠ L2.

  FIG. 4 is a schematic perspective view illustrating the bonding of the surface protective film and the polarizing plate in the method of manufacturing a polarizer using the surface protective film according to one embodiment of the present invention. In one embodiment, a polarizing film laminate is produced using a surface protective film having a long polarizer and a long pressure-sensitive adhesive layer. By using the surface protection film having the pressure-sensitive adhesive layer, as shown in FIG. 4, a polarizing film laminate can be produced by roll-to-roll.

A-1. Production of Polarizer As the polarizer 10 used for the polarizing film laminate 100, any appropriate polarizer may be employed. The polarizer is typically composed of a resin film. The resin film is typically a polyvinyl alcohol resin (hereinafter referred to as "PVA resin") film containing a dichroic substance such as iodine or an organic dye. The resin film (typically, a PVA-based resin film) constituting the polarizer may be a single film, and a resin layer (typically, a PVA-based resin layer) formed on a resin substrate ) May be.

  The polarizer may be made by any suitable method. When the polarizer is a single PVA-based resin film, the polarizer can be produced by methods well known and used in the art. When the polarizer is a PVA-based resin layer formed on a resin substrate, the polarizer can be produced, for example, by the method described in JP-A-2012-73580. The publication is incorporated herein by reference in its entirety.

  The thickness of the polarizer may 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, 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. With such a thickness, a polarizer having excellent durability and optical properties can be obtained. Moreover, when an alkaline process is included as a wet process, a non-polarization part may be formed favorable, so that thickness is thin. For example, when forming a non-polarization part by decolorization by alkali treatment, the contact time of a process liquid and a resin film (polarizer) can be shortened.

  When producing a polarizing film laminated body using a polarizing plate, in one embodiment, a protective film is pasted together to one side or both sides of a polarizer which is a single resin film. In another embodiment, a protective film is attached to the surface of the polarizer of the laminate of resin substrate / polarizer, and then the resin substrate is peeled off, and if necessary, it is separated on the peeling surface of the resin substrate. The protective film of can be laminated. In addition, when it only says a protective film in this specification, the above-mentioned polarizer protective film is meant and it differs from a surface protective film (film which protects a polarizing plate temporarily at the time of operation | work). The lamination of the protective film can be typically performed by roll to roll.

  Examples of materials 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 resin And polyamide resins, polycarbonate resins, and copolymer resins thereof.

  The thickness of the protective film is preferably 10 μm to 100 μm. The protective film is typically laminated to the polarizer via an adhesive layer (specifically, an adhesive layer, an adhesive layer). The adhesive layer is typically formed of a PVA-based adhesive or an activated 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. As a representative example of the optical functional layer, a retardation film (optical compensation film) and a surface treatment layer can be mentioned.

A-2. Production of Surface Protective Film The surface protective film 50 is provided with the through holes 61 corresponding to the portions of the obtained polarizer to be subjected to wet processing (that is, the portions corresponding to the exposed portions 51 of the polarizing film laminate). In one embodiment, the surface protective film is a laminate having any appropriate resin film and an adhesive layer provided on one side of the resin film, and the resin film and the adhesive layer Through-holes (surface protective film in FIG. 2).

  For example, as described above, the through holes 61 of the surface protective film 50 may be arranged at substantially equal intervals in both the longitudinal direction and the width direction (FIG. 3). Alternatively, the through holes 61 may be disposed substantially at equal intervals in the longitudinal direction and may be disposed at different intervals in the width direction; they may be disposed at different intervals in the longitudinal direction and substantially in the width direction. It may be equally spaced (not shown). When the through holes are arranged at different intervals in the longitudinal direction or width direction, the intervals between adjacent through holes may be all different, even if only a part (the interval between specific adjacent through holes) is different. Good. Alternatively, a plurality of regions may be defined in the longitudinal direction of the surface protective film 50, and the intervals of the through holes 61 in the longitudinal direction and / or the width direction may be set for each region.

In one embodiment, in the through holes 61, a straight line connecting adjacent through holes in the long direction is substantially parallel to the long direction, and a straight line connecting adjacent through holes in the width direction. Are arranged substantially parallel to the width direction. In another embodiment, in the through hole 61, a straight line connecting adjacent through holes in the longitudinal direction is substantially parallel to the longitudinal direction, and a straight line connecting adjacent through holes in the width direction Are arranged to have a predetermined angle θ _W with respect to the width direction. In yet another embodiment, in the through hole 61, a straight line connecting adjacent through holes in the longitudinal direction has a predetermined angle θ _L with respect to the longitudinal direction, and adjacent through holes in the width direction A straight line connecting the two 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 ± 10 ° or less. Here, "±" is meant to include both clockwise and counterclockwise directions with respect to the reference direction (longitudinal direction or width direction). By using the surface protective film in which the through holes are arranged as described above, it is possible to form a non-polarization portion in a desired pattern while roll-transporting a long polarizer. As a result, the arrangement pattern can be precisely controlled throughout the elongated polarizer to form a non-polarization portion. Here, depending on the image display device, in order to improve display characteristics, it may be required to shift the absorption axis of the polarizer by about 10 ° at the maximum with respect to the long side or the short side of the device. Since the absorption axis of the polarizer appears in the longitudinal direction or the width direction, by forming the non-polarization portion using the above surface protection film, in such a case, the positional relationship between the non-polarization portion and the absorption axis Can be uniformly controlled in the entire long polarizer, and a final product excellent in axial accuracy (and hence excellent in optical characteristics) can be obtained. Therefore, it is possible to precisely control the direction of the absorption axis of the cut (for example, cut in the longitudinal direction and / or width direction, absorption in the width direction, and the absorption axis of the sheet polarizer) to a desired angle, and Variations in the direction of the absorption axis of can be significantly suppressed. Needless to say, the arrangement pattern of the through holes is not limited to the illustrated example. For example, in the through hole 61, 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 has a width 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 planar view shape of the through hole of the surface protective film may be any suitable shape depending on the purpose. Examples include circles, ovals, squares, rectangles and diamonds.

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

  The surface protective film is preferably a film having high hardness (for example, elastic modulus). This is because deformation of the through hole at the time of transportation and / or pasting can be prevented. As materials for forming the surface protective film, 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. Preferably, it is an ester resin (in particular, a polyethylene terephthalate resin). Such a material has an advantage that the elastic modulus is sufficiently high and deformation of the through hole is unlikely to occur even when tension is applied during transportation and / or bonding.

  The thickness of the surface protective film is typically 20 μm to 250 μm, preferably 25 μm to 200 μm, from the viewpoint that the treatment liquid can be efficiently removed in the treatment liquid removal step described later. In addition, the thickness of the surface protective film may be 30 μm to 150 μm because it has the advantage that deformation of the through holes is unlikely to occur even when tension is applied during transport and / or bonding.

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, there is an advantage that deformation of the through hole is less likely to occur even when tension is applied at the time of conveyance and / or bonding. The elastic modulus is measured in accordance with JIS K 6781.

  The tensile elongation of the surface protective film is preferably 90% to 170%. If the tensile elongation of the surface protective film is in such a range, it has the advantage of being less likely to break during transport. The tensile elongation is measured in accordance with JIS K 6781.

  In the polarizing film laminate 100, as described above, the second surface protective film 30 may be further laminated on the side on which the surface protective film is not disposed. As this second surface protective film, a film similar to the above surface protective film may 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, it is possible to more appropriately protect the polarizing plate (polarizer / protective film) when alkali treatment is included as wet treatment, and as a result, the alkali treatment can be made better. It can be carried out.

  In addition, by using a long film as the second protective film, the second protective film can be laminated by roll-to-roll. In this case, the second surface protective film may be bonded simultaneously with the surface protective film having the through hole, or may be bonded before the surface protective film having the through hole is bonded, the surface having the through hole It may be pasted after pasting together a protective film.

  Any appropriate pressure-sensitive adhesive layer may be employed as the pressure-sensitive adhesive layer as long as the effects of the present invention can be obtained. As base resin of an adhesive, acrylic resin, a styrene resin, silicone resin is mentioned, for example. Acrylic resins are preferable from the viewpoints of chemical resistance, adhesion for preventing the infiltration of the treatment liquid at the time of immersion, freedom to the adherend, and the like. The adhesive may contain a crosslinking agent. Examples of the crosslinking agent that can be contained in the adhesive include isocyanate compounds, epoxy compounds, and aziridine compounds. The adhesive may contain, for example, a silane coupling agent. The formulation of the adhesive may be appropriately set depending on the purpose.

  The pressure-sensitive adhesive layer may be formed by any appropriate method. As a specific example, the method of apply | coating and drying an adhesive solution on a resin film, the method of forming an adhesive layer on a separator, and transferring the said adhesive layer to a resin film etc. are mentioned. Examples of the coating method include reverse coating, roll coating such as gravure coating, spin coating, screen coating, fountain coating, dipping, and spraying.

  The thickness of the pressure-sensitive adhesive layer is preferably 5 μm to 60 μm, more preferably 5 μm to 30 μm. When the thickness is too thin, the adhesiveness is insufficient, and air bubbles and the like may enter the adhesive interface. If the thickness is too thick, problems such as sticking out of the adhesive will easily occur. The thickness of the pressure-sensitive adhesive layer may be adjusted together with the thickness of the resin film so that the thickness of the surface protective film falls within the above range.

B. Wet treatment process In the production method of the present invention, wet treatment is performed using the polarizing film laminate obtained by the above process. Thereby, wet processing can be performed only on the desired portion of the polarizer. Specifically, when performing alkali treatment with a basic solution as wet treatment, the alkali treatment can be performed only on the portion exposed from the surface protective film of the polarizer, and the non-polarization portion may be formed only on this portion it can. Further, in the manufacturing method of the present invention, substantially all the processing liquid can be removed in the processing liquid removing step performed after the wet processing. Therefore, an adverse effect on the appearance of the polarizer due to a water mark or the like formed by evaporation of the remaining treatment liquid can be prevented. In addition, since the treatment liquid remaining in the exposed portion can be prevented from flowing out to a portion not subjected to wet treatment as the surface protection film is peeled off from the polarizing film laminate, the untreated portion, particularly the boundary An adverse effect on the properties of the part can also be prevented.

  There is no restriction | limiting in particular in the contact method of the process liquid and polarizing film laminated body in wet processing, The immersion to a process liquid, the dripping of a process liquid, application | coating or spraying etc. are mentioned. In addition, the contact time between the polarizing film laminate and the treatment liquid may be set to any appropriate time depending on conditions such as the purpose of the wet treatment, the concentration of the treatment liquid, and the thickness of the polarizing film laminate.

  There is no restriction | limiting in particular as a wet process which the said polarizing film laminated body may be provided, The wet process which may be used by the manufacturing process of a polarizer is mentioned. Typically, in a method for producing a polarizer having a non-polarization portion, wet treatment using a basic solution, wet treatment using an acidic solution, and washing after wet treatment using a basic solution and / or an acidic solution Including the steps.

B-1. Wet treatment with alkaline solution (alkali treatment)
The wet treatment (hereinafter also referred to as alkali treatment) using a basic solution can be performed by bringing the polarizing film laminate into contact with the basic solution. Wet treatment with a basic solution may decolorize the exposed parts and the decolorization may form non-polarized parts. In addition, when performing the wet process using a basic solution, as a polarizer used for a polarizing film laminated body, the polarizer containing iodine is preferable. When the polarizer contains iodine as a dichroic substance, the iodine concentration of the exposed portion is reduced by bringing the exposed portion of the polarizer into contact with the basic solution, and as a result, only the exposed portion is selectively non-polarized. The part can be formed. Therefore, the non-polarization part can be selectively formed in a predetermined part of the polarizer with very high manufacturing efficiency without complicated operation. When iodine is left in the polarizer, even if the iodine complex is destroyed to form the non-polarization part, the iodine complex is formed again as the polarizer is used, and the non-polarization part has the desired characteristics. There is a risk that it will not be. In this embodiment, iodine itself is removed from the polarizer (substantially, non-polarization part) by removal of the basic solution described later. As a result, the characteristic change of the non-polarization part accompanying use of a polarizer can be prevented.

  The contacting of the polarizing film laminate with the basic solution may be performed by any suitable means, as described above. In the case of using a long polarizing film laminate as the polarizing film laminate, since the decoloring treatment can be performed while conveying the polarizing film laminate, immersion is preferred from the viewpoint that the production efficiency is significantly increased. . As described above, by using the first surface protective film (and, if necessary, the second surface protective film), the iodine concentration is not reduced in the parts other than the exposed part of the polarizing film, and therefore the non-polarizing part by immersion It is possible to form Specifically, by immersing the polarizing film laminate in a basic solution, only the exposed part in the polarizing film laminate is in contact with the basic solution.

  The formation of the non-polarization part by the basic solution will be described in more detail. After contact with the exposed part of the polarizer in the polarizing film laminate, the basic solution penetrates into the exposed part. The iodine complex contained in the exposed portion is reduced by the base contained in the basic solution to form an iodine ion. By reducing the iodine complex to iodine ions, the polarization performance of the exposed portion substantially disappears, and a non-polarized portion is formed in the exposed portion. In addition, reduction of the iodine complex improves the transmittance of the exposed portion. The iodine ionized moves from the exposed part into the solvent of the basic solution. As a result, iodine ions are also removed from the exposed portion together with the basic solution by the removal of the basic solution described later. In this manner, a non-polarization portion is selectively formed on a predetermined portion of the polarizer, and the non-polarization portion is stable with no change with time. In addition, 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. It is possible to prevent the penetration of the light (as a result, the formation of the non-polarization portion in the undesired portion).

  Any appropriate basic compound can be used as the basic compound contained in the above-mentioned basic solution. As a basic compound, 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 a hydroxide of an alkali metal, the iodine complex can be efficiently ionized, and the non-polarization part can be more easily formed. These basic compounds may be used alone or in combination of two or more.

  Any appropriate solvent can be used as a solvent for the above basic solution. Specific examples thereof include water, alcohols such as ethanol and methanol, ethers, benzene, chloroform, and mixed solvents thereof. The solvent is preferably water or an alcohol, since the iodine ion is favorably transferred to the solvent and the iodine ion can be easily removed in the subsequent removal of the basic solution.

  The concentration of the basic solution is, for example, 0.01 N to 5 N, preferably 0.05 N to 3 N, and more preferably 0.1 N to 2.5 N. If the concentration of the basic solution is in such a range, the iodine concentration in 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 part of the polarizer) and the basic solution is determined by the thickness of the polarizer, the type of basic compound contained in the basic solution to be used, and the basic compound. It can be set according to the concentration of, for example, 5 seconds to 30 minutes.

  The above-mentioned basic solution may be removed by any appropriate means after the contact with the exposed part of the polarizer (after the formation of the non-polarized part) as needed. Specific examples of the method of removing the basic solution include suction and removal, natural drying, heat drying, blast drying, reduced pressure drying, and a treatment liquid removing step and washing using a treatment liquid removing member described later. The drying temperature when removing the basic solution by drying is, for example, 20 ° C. to 100 ° C.

B-2. Wet treatment using an acidic solution (acid treatment)
The wet treatment (hereinafter also referred to as acid treatment) using an acidic solution can be performed by contacting the polarizing film laminate with an acidic solution. It is preferable that wet treatment using an acidic solution is performed in combination with the above-mentioned alkali treatment, and after alkaline treatment, wet treatment using an acidic solution is performed. After alkali treatment, by contacting with an acidic solution, the basic solution remaining in the non-polarization part can be removed to an even better level. Moreover, the dimensional stability and durability of the non-polarization part can be improved by contacting with an acidic solution.

  The contacting of the polarizing film laminate with the acidic solution may be performed by any suitable means. Specifically, the immersion in the acidic solution of a polarizing film laminated body, or the dripping to the polarizing film laminated body of an acidic solution, application | coating, or spraying is mentioned. The contact with the acidic solution is preferably immersion, as in the case of the contact with the basic solution. The contact with the acidic solution may be performed after removing the basic solution, or may be performed without removing the basic solution.

  Any appropriate acidic compound can be used as the acidic compound contained in the above-mentioned 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 acidic compound contained in the acidic solution is preferably an inorganic acid, more preferably hydrochloric acid, sulfuric acid or nitric acid. These acidic compounds may be used alone or in combination.

  As a solvent of the above-mentioned acidic solution, what was illustrated as a solvent of the above-mentioned basic solution can be used. The concentration of the acidic solution is, for example, 0.01 N to 5 N, preferably 0.05 N to 3 N, and more preferably 0.1 N to 2.5 N.

  The liquid temperature of the acidic solution is, for example, 20 ° C to 50 ° C. The contact time between the polarizing film laminate (substantially, the exposed part of the polarizer) and the acidic solution is determined by the thickness of the resin film (polarizer), the type of acidic compound contained in the acidic solution to be used, and the acidic compound It can be set according to the concentration of, for example, 5 seconds to 30 minutes. As needed, after contacting a polarizing film laminated body and an acidic solution, you may remove immediately.

  The above acidic solution may be removed by any appropriate means after the contact with the exposed part of the polarizer, as needed. Specific examples of the method of removing the acidic solution include suction and removal, natural drying, heat drying, blast drying, reduced pressure drying, and a treatment liquid removing step and washing using a treatment liquid removing member described later. When removing an acidic solution by drying, it can carry out, for example by conveying a polarizing film laminated body in oven. The drying temperature is, for example, 20 ° C. to 100 ° C., and the drying time is, for example, 5 seconds to 600 seconds.

B-3. Cleaning Cleaning may be performed to remove the treatment liquid and foreign matter adhering to the surface of the polarizing film laminate in each step. For example, in the production method of the present invention, it can be performed after the above-mentioned alkali treatment and / or acid treatment.

  Examples of the liquid used for washing include water (pure water), alcohols such as methanol and ethanol, an acidic aqueous solution, and a mixed solvent of these. Preferably, it is water. The washing may be performed once or a plurality of washings may be performed as one step.

  The treatment liquid after washing may be removed by any appropriate means as needed. Specific examples of the method for removing the treatment liquid after washing include suction and removal, natural drying, heating and drying, blast drying, reduced pressure drying, and a treatment liquid removing step using a treatment liquid removing member described later. It is preferable to be removed by the process liquid removal process using the process liquid removal member mentioned later. The washing step can usually be performed at the end of the wet processing that can be included in the manufacturing process of the polarizer. Therefore, by removing the treatment liquid after the washing treatment using the treatment liquid removing member, it is possible to prevent the loss of the appearance of the obtained polarizer due to water marks and the like due to evaporation of the treatment liquid remaining. In addition, since the treatment liquid remaining in the exposed portion of the polarizing film laminate can be prevented from flowing out to a portion not subjected to wet treatment as the surface protective film is peeled off, an untreated portion of the polarizer, In particular, adverse effects on the characteristics of the boundary portion can also be prevented.

C. Treatment Liquid Removal Step In the treatment liquid removal step of the present invention, the member for treatment liquid removal made of a material capable of following the exposed portion is brought into contact with the polarizing film laminate from the surface protective film side of the polarizing film laminate. To be done. As a result, the treatment liquid removing member may enter the exposed portion, and the treatment liquid remaining on the exposed portion of the polarizing film laminate may be removed. As a result, the appearance of the polarizer can be prevented from being impaired due to water marks and the like due to evaporation of the treatment liquid remaining in the exposed portion. In addition, depending on the treatment liquid used for the wet treatment, the characteristics of the polarizer may be affected. Therefore, when the removal of the treatment liquid remaining in the exposed part is insufficient, when the surface protective film is peeled off, the treatment liquid may also adhere to parts other than the exposed part of the polarizer. In this case, the characteristics of the non-wet-treated portion of the polarizer may be changed, and the effect of treating only the exposed portion using the surface protective film may not be obtained sufficiently. However, by passing through the treatment liquid removal step after the wet treatment, it is possible to prevent the influence of the remaining treatment liquid on the characteristics of the untreated part of the polarizer. Therefore, the effect which processes only to a desired part using a surface protective film may be exhibited further.

  In the method of manufacturing a polarizer having a non-polarization portion, when a plurality of wet treatments are performed, the treatment liquid removing step may be performed only after the last wet treatment, or may be performed for each wet treatment. It may be performed only after wet treatment.

  The contact between the member for removing the treatment liquid and the polarizing film laminate may be performed continuously using a means such as a roll, and the member for removing the treatment liquid and the polarizing film laminate are brought into contact with each other by hand. You may go. The treatment liquid removing step is preferably performed by attaching a treatment liquid removing member to a rotating body such as a roll and passing the polarizing film laminate between a pair of rotating bodies. When processing is performed by attaching a treatment liquid removing member to a rotating body, a long polarizing film laminate is suitably used. Thus, the production efficiency of the polarizer having the non-polarization part can be improved by performing the treatment liquid removing step. Hereinafter, the process liquid removal process is concretely demonstrated by making a elongate polarizing film laminated body into an example.

  FIG. 5 is a schematic view showing a process liquid removing process according to one embodiment of the present invention. The polarizing film laminate 100 subjected to the wet processing was taken up from the processing bath, and the processing liquid removing members 200 and 200 'made of a material capable of following the exposed portion were attached so as to surround the circumference thereof. It passes between the rotating bodies 300 and 300 ', such as rolls, and is subjected to a later process. As a result, the treatment liquid removing member 200 made of a material capable of following the exposed portion enters the exposed portion, and the remaining treatment liquid is removed. Preferably, the polarizing film laminate 100 is passed between the rotating bodies 300 and 300 'under any appropriate pressure. In the illustrated example, the members 200 and 200 'for removing the treatment liquid are attached to both of the rotating bodies 300 and 300', but the member for removing the treatment liquid is at least the rotating body on the side in contact with the exposed portion 51 of the polarizing film laminate. It should just be attached to.

  The treatment liquid removing member 200 is a member for removing the treatment liquid attached to the surface of the polarizing film laminate by contacting from the surface protective film 50 side of the polarizing film laminate. The treatment liquid removing member is made of a material that can follow the exposed portion. Thereby, when the member 200 for a process liquid removal contacts a surface protection film, it may approach in the exposed part 51, and may contact with the wall surface of the through-hole 61, and / or the surface of the polarizer exposed from the surface protection film. The treatment liquid removing member made of a material capable of following the exposed portion comes in contact with the wall surface of the through hole 61 and / or the surface of the polarizer exposed from the surface protective film, thereby removing the treatment liquid remaining in the exposed portion It can be done. The member for removing the treatment liquid preferably has water absorbency. By using the treatment liquid removing member having water absorbability, the treatment liquid can be removed more efficiently. In the illustrated example, the surface shape of the treatment liquid removing members 200 and 200 ′ is flat, but the surface of the treatment liquid removing member may have unevenness. When the surface of the treatment liquid removing member has irregularities, the irregularities may be irregularities derived from the member to be used (for example, irregularities of the cloth surface which may be formed of fibers) or even irregularities optionally formed. Good.

  Any appropriate material can be used as a material that constitutes the treatment liquid removal member. For example, rags, cloth, sponge, chamomile towel, chamomile skin, etc. may be mentioned. It is preferable to use a member having flexibility because it can follow the shape of the exposed part of the polarizing film laminate. A member having water absorption and flexibility is particularly preferably used. The treatment liquid removing member may be composed of one kind of material, or may be composed of two or more kinds of materials in combination.

  The cloth used as the treatment liquid removing member may be a woven or non-woven fabric. Arbitrary suitable fiber can be used as a fiber which comprises the cloth used as a member for process liquid removal. Examples of the fibers include cotton, wool, rayon, polyamide fibers (specifically, nylon), polyester fibers, acrylic fibers, polyvinyl alcohol (PVA) fibers and the like. PVA-based fibers are preferred in terms of excellent water absorption and flexibility.

  The sponge used as the treatment liquid removing member can be configured using any appropriate material. Examples of the material constituting the sponge include sponge rubber, rubber such as natural rubber or synthetic rubber, polyurethane resin, melamine resin, PVA resin, polyvinyl chloride (PVC) resin and the like. From the viewpoint of excellent water absorption and flexibility, PVA resins are preferable. When manufacturing the polarizer which has a non-polarization part using a elongate polarizing film laminated body, the sponge roll comprised with a sponge is used suitably.

  The same towel used as a treatment liquid removing member is made of any appropriate material. Examples of the material constituting the same towel include PVA-based resin, polyester-based resin and the like. In addition, as chamomile skin, natural chamomile skin may be used, or synthetic chamomile skin may be used. Any suitable material can be used as a material for synthetic chamois.

  When a sponge is used as the treatment liquid removing member, the porosity of the sponge is preferably 80% or more, more preferably 90% or more, and still more preferably 95% or more. When the porosity of the sponge is 80% or more, it is possible to obtain a treatment liquid removing member having high water absorption and excellent in the removal efficiency of the treatment liquid.

The member used for the treatment liquid removing member preferably has a water absorption of 50% or more, more preferably 100% or more, still more preferably 200% or more, and particularly preferably 300% or more. By using a member having a water absorption of 50% or more, the treatment liquid can be more suitably removed. The higher the water absorption, the better, and the upper limit may vary depending on the member used. In the present specification, the water absorption rate of the treatment liquid removing member refers to a value obtained by the following equation.

Water absorption rate (%) = (weight of test piece after immersion−weight of test piece before immersion) / weight of test piece before immersion × 100

  The treatment liquid removing member has, for example, a sponge hardness of 0 to 80, preferably 10 to 30. When the sponge hardness is within the above range, the treatment liquid removing member and the exposed portion of the surface protective film can be sufficiently brought into contact, and the treatment liquid remaining in the exposed portion can be sufficiently removed. In the present specification, the sponge hardness refers to a value measured by an Asker C-type hardness tester in accordance with SRIS 0101.

  The thickness of the treatment liquid removing member may be set to any appropriate value depending on the depth of the exposed portion (i.e., the thickness of the surface protective film). The thickness of the treatment liquid removing member is, for example, 5 mm to 50 mm, preferably 7 mm to 30 mm, and more preferably 10 mm to 25 mm. When the thickness of the treatment liquid removing member is in the above range, the treatment liquid can be efficiently removed. In addition, even when pressure is applied, the thickness of the treatment liquid removing member can be sufficiently maintained, and the removal efficiency can be maintained.

  In FIG. 5, the rotating bodies 300 and 300 ′ to which the processing liquid removing members 200 and 200 ′ are attached are one set, but two or more sets of rotating bodies may be arranged to perform the processing liquid removing step. When the treatment liquid removing process is performed using two or more sets of rotating bodies, the members for treatment liquid removing attached to each rotating body may be the same or different.

  The treatment liquid removal step is preferably performed by bringing the polarizing film laminate and the treatment liquid removal member into contact with each other while applying any appropriate pressure. By bringing the polarizing film laminate into contact with the treatment liquid removing member while applying pressure, the treatment liquid removing member made of a material capable of following the exposed part is more closely attached to the exposed part of the polarizing film laminate. It can. Therefore, the treatment liquid can be more preferably removed from the surface of the polarizing film laminate, particularly from the exposed portion.

  FIG. 6 is a schematic view showing a treatment liquid removing process according to another embodiment of the present invention, and is a schematic view in the case where the treatment liquid removing process is performed while applying pressure to the elongated polarizing film laminate. In this embodiment, by applying pressure, the treatment liquid removing member made of a material capable of following the exposed portion can be more closely attached to the exposed portion. In this embodiment, the polarizing film laminate 100 is passed between the rolls 300, 300 'while applying any appropriate pressure to the rolls 300, 300' to which the treatment liquid removing members 200, 200 'are attached. By applying pressure, the treatment liquid removing member 200 made of a material capable of following the exposed portion penetrates deeper into the exposed portion 51 and contacts at least the bottom of the exposed portion 51 (that is, the surface of the polarizer). Do. By applying pressure, it is preferable that the treatment liquid removing member be in contact so as to sufficiently follow the shape of the exposed portion 51. Usually, the treatment liquid attached to the wall surface of the bottom of the exposed portion is also in contact with the bottom surface of the exposed portion by surface tension. Therefore, the treatment liquid can be removed by contacting the treatment liquid removing member made of a material capable of following the exposed portion at least with the bottom surface of the exposed portion. In addition, since the material capable of following the exposed portion has flexibility, the processing liquid removing member also functions as a buffer. Therefore, even when the treatment liquid removal step is performed while applying pressure, excessive load on the polarizing film laminate can be prevented.

  The pressure at the time of bringing the processing liquid removing member into contact with the polarizing film laminate may be set to any appropriate value. The pressure at the time of bringing the member for treatment liquid removal into contact with the polarizing film laminate is preferably 0.1 kPa to 500 kPa, and more preferably 1 kPa to 100 kPa. When the pressure is in the above range, the treatment liquid can be removed without applying an excessive load to the polarizing film laminate.

  In addition, before the process liquid removing step by the process liquid removing member, the process solution may be removed in advance by other means such as a drainage blower. By removing the treatment liquid in advance by a drainage blower or the like, the amount of treatment liquid remaining in the exposed portion can be reduced, and the removal efficiency of the treatment liquid in the treatment liquid removing step can be further improved.

D. Other Steps After the treatment liquid removal step, a further drying step may be performed by any appropriate means. The treatment liquid is sufficiently removed in the polarizing film laminate which has passed the treatment liquid removal step. Therefore, even when it is subjected to a drying process thereafter, the formation of a water mark or the like due to the remaining treatment liquid can be prevented. Therefore, the appearance defect of the polarizer finally obtained can be prevented.

  As a drying means, any suitable method can be used. As a drying means, oven, IR heater, warm air drying etc. are mentioned, for example. The drying temperature and the drying time may be set to any appropriate values depending on the thickness, properties and the like of the polarizing film laminate. The drying temperature may be set, for example, at 30 ° C to 80 ° C. The drying time may be set to, for example, 0.2 minutes to 30 minutes.

  After finishing the necessary steps, the surface protective film can be peeled off from the polarizing film laminate.

E. A Polarizer Having a Non-Polarized Part The manufacturing method of the present invention, as described above, comprises a member for removing a treatment liquid made of a material capable of following an exposed part, and the polarizing film laminate, the surface of the polarizing film laminate. The process liquid removal process made to contact from the protective film side is included. Therefore, it can be prevented that the treatment liquid used for the wet treatment remains, and the residual treatment liquid evaporates to form a water mark or the like. Therefore, a polarizer having a non-polarization part obtained by the production method of the present invention has an excellent appearance. Furthermore, by passing through the treatment liquid removing step, the treatment liquid remaining in the exposed part is prevented from flowing out to the part not subjected to the wet treatment along with the peeling of the surface protective film from the polarizing film laminate. Can also prevent adverse effects on the properties of the untreated part, in particular of the border part.

  The single transmittance (Ts) of the obtained polarizer (excluding the non-polarized portion) is preferably 39% or more, more preferably 39.5% or more, still more preferably 40% or more, particularly preferably 40.5% or more It is. The theoretical upper limit of single transmittance is 50%, and the practical upper limit is 46%. Moreover, single-piece | unit transmittance | permeability (Ts) is Y value which measured and measured visual sensitivity by 2 degree visual field (C light source) of JISZ8701, for example, using a microspectroscopic light system (lambda vision made, LVmicro) It can be measured. The degree of polarization (excluding the non-polarization portion) of the polarizer is preferably 99.9% or more, more preferably 99.93% or more, and still more preferably 99.95% or more.

  The transmittance of the non-polarization portion (for example, the transmittance measured at a wavelength of 550 nm at 23 ° C.) is preferably 50% or more, more preferably 60% or more, and still more preferably 75% or more. Particularly preferably, it is 90% or more. With such a transmittance, desired transparency as a non-polarization part can be secured. As a result, when the polarizer is disposed such that the non-polarization 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.

  The planar view shape of the non-polarization part may be any suitable shape as long as it does not adversely affect the camera performance of the image display device in which the polarizer is used. The planar view shape of the non-polarization part corresponds to the shape of the through hole of the first surface protective film.

  In one embodiment, the absorption axis of the polarizer is substantially parallel to the longitudinal or width direction, and both ends of the polarizer are slit parallel to the longitudinal direction. With such a configuration, by performing the cutting operation based on the end face of the polarizer, it is possible to easily manufacture a plurality of polarizers having a non-polarization portion and having an absorption axis in an appropriate direction. .

  The polarizer may 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 (not shown). Practically, the polarizing plate has a pressure-sensitive adhesive layer as the outermost layer. The pressure-sensitive adhesive layer is typically the outermost layer on the image display device side. A separator is releasably and temporarily attached to the pressure-sensitive adhesive layer, thereby protecting the pressure-sensitive adhesive layer until actual use and enabling roll formation.

  The polarizing plate may further have any appropriate optical functional layer depending on the purpose. As a representative example of the optical functional layer, a retardation film (optical compensation film) and a surface treatment layer can be mentioned. For example, a retardation film may be disposed between the protective film and the pressure-sensitive adhesive layer. The optical properties (for example, refractive index ellipsoid, in-plane retardation, thickness direction retardation) of the retardation film may be appropriately set according to the purpose, the characteristics of the image display apparatus, and the like. For example, when the image display device is a liquid crystal display device of IPS mode, a retardation film having a refractive index ellipsoid of nx> ny> nz and a retardation film having a refractive index ellipsoid of nz> nx> ny It can be arranged. The retardation film may also serve as a protective film. In this case, the protective film may be omitted. Conversely, the protective film may have an optical compensation function (that is, may have an appropriate refractive index ellipsoid, in-plane retardation, and thickness retardation) according to the purpose. Here, "nx" is the refractive index in the direction in which the refractive index in the film plane is maximum (that is, the slow axis direction), and "ny" is the refractive index in the film plane in the direction orthogonal to the slow axis. “Nz” is the refractive index in the thickness direction.

  The surface treatment layer may be disposed on the viewing side of the polarizing plate. As a representative example of the surface treatment layer, a hard coat layer, an antireflective layer and an antiglare layer can be mentioned. The surface treatment layer is preferably, for example, a layer having a low moisture permeability for the purpose of improving the humidification durability of the polarizer. The hard coat layer is provided for the purpose of preventing the surface of the polarizing plate from being scratched or the like. The hard coat layer can be formed, for example, by a method of adding a cured film excellent in hardness, slip characteristics and the like by an appropriate ultraviolet curable resin such as acrylic resin or silicone resin to the surface. The hard coat layer preferably has a pencil hardness of 2H or more. The antireflective layer is a low reflective layer provided for the purpose of preventing the reflection of external light on the surface of the polarizing plate. As the antireflection layer, for example, a thin layer type which prevents reflection by utilizing the canceling effect of the reflected light due to the interference of light as disclosed in JP-A-2005-248173, JP-A-2011-2759. The surface structure type which expresses low reflectance by giving a fine structure to the surface as disclosed in is mentioned. The antiglare layer is provided for the purpose of preventing external light from being reflected on the surface of the polarizing plate to thereby inhibit visual recognition of the light transmitted through the polarizing plate. The antiglare layer is formed, for example, by imparting a fine uneven structure to the surface by an appropriate method such as a roughening method by a sand blast method or an embossing method, or a compounding method of transparent fine particles. The antiglare layer may also function as a diffusion layer (such as a viewing angle enlargement function) for diffusing the light transmitted through the polarizing plate to enlarge the viewing angle or the like. Instead of providing the surface treatment layer, the surface of the protective film on the viewing side may be subjected to the same surface treatment.

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

Example 1
A pressure-sensitive adhesive (acrylic pressure-sensitive adhesive) was applied to one surface of a resin film (thickness 38 μm) to a thickness of 10 μm. Subsequently, the through-hole of diameter 4 mm was produced using the picnal blade for the laminated body of the obtained resin film and an adhesive layer, and the surface protection film was obtained.
Bonding so that the polarizer side surface of the polarizing plate (polarizer (transmittance 42.3%, thickness 5 μm) / protective film (thickness 25 μm)) with a total thickness of 30 μm is in contact with the adhesive layer side of the surface protective film A polarizing film laminate was obtained. From the surface protective film of the obtained polarizing film laminate, an aqueous solution of sodium hydroxide (0.5 mol / L (0.5 N)) at ordinary temperature was dropped to a portion where the polarizer was exposed, and left for 1 minute. Then, the dropped aqueous solution of sodium hydroxide was removed by wiping using a rag as a member for removing a treatment liquid. After removal, the polarizing film laminate was dried in an oven at 40 ° C. for 1 minute. After drying, the surface protective film was peeled off to obtain a polarizing plate having a non-polarization portion.
The periphery of the non-polarization part (part exposed from the through-hole of the surface protection film) of the obtained polarizing plate was visually observed, and the external appearance was evaluated. In the obtained polarizing plate, the exposed part of the polarizer (the part corresponding to the through hole of the surface protective film) is a non-polarized part. No traces of the liquid used for the treatment were found around the non-polarization part of the obtained polarizing plate.

Example 2
A polarizing plate having a non-polarization portion was obtained in the same manner as in Example 1 except that a cloth (synthetic chamois skin) was used as a treatment liquid removing member.
The periphery of the non-polarization part (part exposed from the through-hole of the surface protection film) of the obtained polarizing plate was visually observed, and the external appearance was evaluated. In the obtained polarizing plate, the exposed part of the polarizer (the part corresponding to the through hole of the surface protective film) is a non-polarized part. No traces of the liquid used for the treatment were found around the non-polarization part of the obtained polarizing plate.

[Example 3]
Using a sponge roll (PVA sponge) as a treatment liquid removing member, after dropping an aqueous solution of sodium hydroxide, the polarizing film laminate which was left to stand for 1 minute was passed between two sponge rolls, except that Similarly, a polarizing plate having a nonpolarizing portion was obtained.
The periphery of the non-polarization part (part exposed from the through-hole of the surface protection film) of the obtained polarizing plate was visually observed, and the external appearance was evaluated. In the obtained polarizing plate, the exposed part of the polarizer (the part corresponding to the through hole of the surface protective film) is a non-polarized part. No traces of the liquid used for the treatment were found around the non-polarization part of the obtained polarizing plate.

Example 4
A polarizing plate was obtained in the same manner as in Example 1 except that pure water was used instead of the aqueous sodium hydroxide solution.
The periphery of the part exposed from the through-hole of the surface protection film of the obtained polarizing plate was visually observed, and the external appearance was evaluated. No trace of the liquid used for the treatment was observed around the portion corresponding to the through hole of the surface protective film of the obtained polarizing plate.

(Comparative example 1)
A polarizing plate having a non-polarization portion was obtained in the same manner as in Example 1 except that the step of contacting with the treatment liquid removing member was not performed.
The periphery of the non-polarization part (part exposed from the through-hole of the surface protection film) of the obtained polarizing plate was visually observed, and the external appearance was evaluated. In the obtained polarizing plate, the exposed part of the polarizer (the part corresponding to the through hole of the surface protective film) is a non-polarized part. A white powder was deposited on the exposed portion (the portion treated with the aqueous sodium hydroxide solution) from the surface protective film of the obtained polarizing plate.

(Comparative example 2)
A polarizing plate having a non-polarization portion was obtained in the same manner as in Example 1 except that a metal blade was used as a treatment liquid removing member.
The periphery of the non-polarization part (part exposed from the through-hole of the surface protection film) of the obtained polarizing plate was visually observed, and the external appearance was evaluated. In the obtained polarizing plate, the exposed part of the polarizer (the part corresponding to the through hole of the surface protective film) is a non-polarized part. In the exposed portion from the surface protective film of the obtained polarizing plate (the portion treated with an aqueous solution of sodium hydroxide), white powder precipitated in a circular shape (corresponding to the shape of the through hole) around the non-polarized portion.

(Comparative example 3)
A polarizing plate having a non-polarization portion was obtained in the same manner as in Example 1 except that a blower was used instead of the treatment liquid removing member in the treatment liquid removing step.
The periphery of the non-polarization part (part exposed from the through-hole of the surface protection film) of the obtained polarizing plate was visually observed, and the external appearance was evaluated. In the obtained polarizing plate, the exposed part of the polarizer (the part corresponding to the through hole of the surface protective film) is a non-polarized part. In the exposed portion from the surface protective film of the obtained polarizing plate (the portion treated with an aqueous solution of sodium hydroxide), white powder precipitated in a circular shape (corresponding to the shape of the through hole) around the non-polarized portion.

(Comparative example 4)
A polarizing plate was obtained in the same manner as in Example 1 except that pure water was used instead of the aqueous sodium hydroxide solution, and a blower was used instead of the processing liquid removal member in the processing liquid removal step.
The periphery of the part exposed from the through-hole of the surface protection film of the obtained polarizing plate was visually observed, and the external appearance was evaluated. Water marks were generated in a circular shape (corresponding to the shape of the through hole) around the portion corresponding to the through hole of the surface protective film of the obtained polarizing plate.

  In Examples 1 to 4 in which the liquid was removed by bringing the treatment liquid removing member into contact with the surface protection film and the portion exposed from the surface protection film of the polarizer, the obtained polarizing plate was used for the treatment. No traces of liquid were observed, and a polarizing plate having an excellent appearance was obtained.

  In Comparative Example 1 in which the treatment liquid removing step was not performed, white powder was deposited on the wet-treated portion of the polarizing plate. In Comparative Example 2 in which a metal blade was used as a treatment liquid removing member, white powder was deposited around the non-polarization portion (portion corresponding to the periphery of the through hole). It was considered that the metal blade, which had difficulty in following the exposed portion, did not have sufficient contact with the exposed portion of the polarizer, so that the liquid used for the wet treatment remained in the exposed portion, particularly at the edge. In addition, white powder was deposited around non-polarized light (a portion corresponding to the periphery of the through hole) also in Comparative Example 3 in which the liquid was removed by blowing air using a blower instead of the contact. Even when a blower was used, it was considered that the liquid used in the treatment was sprayed to the wall surface portion of the exposed portion by air blowing, and as a result, white powder was deposited on the portion corresponding to the periphery of the exposed portion. In Comparative Examples 1 to 3, a sodium hydroxide aqueous solution is used for the wet treatment. Therefore, it was considered that sodium hydroxide was precipitated in the polarizing plates obtained in Comparative Examples 1 to 3. Also, in Comparative Example 4 in which pure water was used instead of the aqueous solution of sodium hydroxide, traces of water evaporated by drying were observed in the portions corresponding to the peripheries of the through holes.

  The polarizer of the present invention is suitably used for a camera-equipped image display device (liquid crystal display device, organic EL device) such as a mobile phone such as a smartphone, a notebook PC, and a tablet PC.

DESCRIPTION OF SYMBOLS 10 Polarizer 20 Protective layer 30 2nd surface protective film 50 1st surface protective film 70 Resin film 80 Adhesive layer 100 Polarized film laminated body 200 Member for processing liquid removal 300 Rotor

Claims (5)

Wet processing of a polarizing film laminate having a polarizer and a surface protection film having through holes disposed on one side of the polarizer, and having an exposed part in which the polarizer is exposed from the through holes on the one side The process to
Removing the treatment liquid used in the wet treatment attached to the surface of the polarizing film laminate,
As the wet treatment, a step of contacting the exposed portion with a basic solution as a treatment liquid to form a non-polarized portion,
The step of removing the treatment liquid is performed by bringing the member for treatment liquid removal constituted of a material capable of following the exposed portion and the polarizing film laminate from the surface protective film side of the polarizing film laminate. And a method of manufacturing a polarizer having a non-polarization part.   The method for producing a polarizer having a non-polarization part according to claim 1, wherein the treatment liquid removing member is at least one selected from the group consisting of waste, cloth, sponge, chamomile towel, and chamois skin.   The polarizer which has a non-polarization part according to claim 1 or 2 which contacts said member for processing solution removal and a polarizing film layered product under pressure of 0.1 kPa-500 kPa in the process of removing said processing solution. Manufacturing method.   The method for manufacturing a polarizer having a non-polarization part according to any one of claims 1 to 3, wherein the step of removing the treatment liquid is performed by the member for treatment liquid removal attached to a rotating body. The wet processing to sanshool sense with the acid solution, and at least one selected from the group consisting of the washing step further, the polarizer having a non-polarizing unit according to any one of claims 1 to 4 Production method.

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