JP6621579B2 - Polarizing film laminate and method for producing a polarizer having a non-polarizing part using the polarizing film laminate - Google Patents

Description

  The present invention relates to a polarizing film laminate and a method for producing a polarizer having a non-polarizing part using the polarizing film laminate.

  Some image display devices such as mobile phones and notebook personal computers (PCs) are equipped with internal electronic components such as cameras. Various studies have been made for the purpose of improving the camera performance and the like of such an image display device (for example, Patent Documents 1 to 6). However, with the rapid spread of smartphones and touch panel type information processing devices, further improvements in camera performance and the like are desired. Further, in order to cope with diversification and high functionality of the shape of the image display device, there is a demand for a polarizing plate partially having polarization performance. In order to realize these demands industrially and commercially, it is desired to manufacture an image display device and / or its components at an acceptable cost. Matters are left behind.

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

  The present invention has been made to solve the above-described conventional problems, and a main object thereof is to provide a polarizing film laminate that can be suitably used in manufacturing a polarizer having a non-polarizing portion. .

The polarizing film laminate of the present invention includes a polarizer, a first surface protective layer having an opening disposed on one side of the polarizer, and a second surface disposed on the other side of the polarizer. And a protective layer.
In one embodiment, the polarizing film laminate of the present invention further includes a protective film disposed between the polarizer and the second surface protective layer, and the second surface protective layer is provided on the protective film. It is pasted together.
In one embodiment, the second surface protective layer is disposed on the outermost side on one side of the polarizer.
According to another situation of this invention, the manufacturing method of the said polarizing film laminated body is provided. The polarizing film laminate manufacturing method includes the step of laminating the second surface protective layer on one side of the polarizer and the first side on the other side of the polarizer on which the second surface protective layer is laminated. Laminating a surface protective layer.
According to another situation of this invention, the manufacturing method of the polarizer which has a non-polarizing part is provided. The method for producing a polarizer having a non-polarizing part is prepared by preparing the polarizing film laminate and immersing the polarizing film laminate in a treatment liquid to partially decolorize the polarizer. Forming a polarizing portion.
In one embodiment, the method for producing a polarizer having a non-polarizing part of the present invention further includes removing the second surface protective layer after the decolorization.
In one embodiment, the polarizing film laminate is a laminate of the protective film and the second surface protective layer such that the protective film is on the polarizer side, and one of the polarizers is provided. It is obtained by laminating on the side.

  By using the polarizing film laminate of the present invention when producing a polarizer having a non-polarizing part, the polarizing film laminate can be continuously immersed in the treatment liquid while being rolled, so that various selective The processing efficiency of simple processing can be greatly increased. Furthermore, it is possible to realize a low-cost, high-yield, high-productivity manufacturing of a polarizer suitable for multifunctional and high-functionality electronic devices such as image display devices.

It is a schematic perspective view of the polarizing film laminated body by one embodiment of this invention. It is a fragmentary sectional view of the polarizing film laminated body shown in FIG. It is a schematic sectional drawing of the 2nd surface protection layer used for one embodiment of the present invention. It is a schematic sectional drawing of the 2nd surface protection layer used for another embodiment of the present invention. It is a schematic perspective view explaining the manufacturing method of the polarizing film laminated body by one Embodiment of this invention. It is the schematic explaining the manufacturing method of the polarizer which has a non-polarization part by one Embodiment of this invention.

  Hereinafter, although embodiment of this invention is described, this invention is not limited to these embodiment.

A. Polarizing film laminate A-1. 1 is a schematic perspective view of a polarizing film laminate according to one embodiment of the present invention, and FIG. 2 is a partial sectional view of the polarizing film laminate shown in FIG. As shown in FIG. 1, the polarizing film laminated body 100 may be elongate. The polarizing film laminate 100 can be wound into a roll.

  As shown in FIG. 2, the polarizing film laminate 100 includes a polarizer 30, a first surface protective layer 40 that is disposed on one side (upper surface side in the illustrated example) of the polarizer 30 and has an opening 41, And a second surface protective layer 10 disposed on the other side (lower surface side in the illustrated example) of the polarizer 30. The polarizing film laminate 100 typically has an exposed portion 31 where the polarizer 30 is exposed on the first surface protective layer 40 side. In the illustrated example, the exposed portion 31 is defined by an opening 41 formed in the first surface protective layer 40. A portion corresponding to the exposed portion 31 of the polarizer 30 may be a non-polarizing portion by any appropriate processing. In the illustrated example, the polarizing film laminate 100 further includes a protective film 20 disposed between the polarizer 30 and the second surface protective layer 10. The second surface protective layer 10 can be bonded to the protective film 20. In the illustrated example, the second surface protective layer 10 is disposed on the outermost side on one side of the polarizer 30. In addition, in this specification, a surface protective layer is a layer which protects a polarizing plate temporarily at the time of manufacture.

  The second surface protective layer 10 can be removed at any appropriate timing. The 2nd surface protective layer 10 may be laminated | stacked so that peeling is possible.

  In the example shown in FIG. 1, the second surface protective layer 10 (not shown), the polarizer 30 and the first surface protective layer 40 are elongated. The longitudinal direction of the second surface protective layer 10, the longitudinal direction of the polarizer 30, and the longitudinal direction of the first surface protective layer 40 are substantially parallel. In one embodiment, the width dimension of the second surface protective layer 10 and the first surface protective layer 40 is designed to be substantially the same as or larger than the width dimension of the polarizer 30. In the present specification, the “elongate shape” means an elongated shape having a sufficiently long length with respect to the width, for example, an elongated shape having a length of 10 times or more, preferably 20 times or more with respect to the width. Includes shape.

  In the example shown in FIG. 1, the exposed portions 31 are arranged at predetermined intervals (that is, in a predetermined pattern) in the longitudinal direction and / or the width direction. The arrangement pattern of the exposed portions 31 can be appropriately set according to the purpose. Typically, when the exposed portion 31 is cut into a predetermined size (for example, cutting and punching in the longitudinal direction and / or the width direction) in order to attach the polarizer 30 to an image display device of a predetermined size, It is arranged at a position corresponding to the camera unit of the image display device.

  In the case of cutting only one size of polarizer from one long polarizer 30, the exposed portion 31 is substantially equally spaced in both the long direction and the width direction as shown in FIG. Can be arranged. With such a configuration, it is easy to control the cutting of the polarizer to a predetermined size in accordance with the size of the image display device, and the yield can be improved. Furthermore, the dispersion | variation in the position of the non-polarizing part (exposed part) in the cut | judged sheet | seat polarizer (polarizing film laminated body) can be suppressed. Note that “substantially equidistant in both the longitudinal direction and the width direction” means that the spacing in the longitudinal direction is equal and the spacing in the width direction is equal. The interval in the scale direction and the interval in the width direction need not be equal. For example, when the interval in the longitudinal direction is L1 and the interval in the width direction is L2, L1 = L2 may be satisfied, or L1 ≠ L2.

  When cutting a plurality of size polarizers from one long polarizer 30, the interval between the exposed portions 31 in the long direction and / or the width direction should be changed according to the size of the polarizer to be cut. Can do. For example, the exposed portions 31 may be arranged at substantially equal intervals in the longitudinal direction and may be arranged at different intervals in the width direction; The directions may be arranged at substantially equal intervals. When the exposed portions 31 are arranged at different intervals in the longitudinal direction or the width direction, the intervals between adjacent exposed portions may be all different or only a part (specific adjacent exposure intervals) may be different. Good. Moreover, a some area | region may be prescribed | regulated in the elongate direction of the polarizing film laminated body 100, and the space | interval of the exposed part 31 in a elongate direction and / or the width direction may be set for every area | region. The exposed portion can be formed in any appropriate arrangement pattern according to the purpose in the long polarizing film laminate.

In one embodiment, the exposed portion 31 has a straight line connecting the adjacent exposed portions 31 in the longitudinal direction substantially parallel to the longitudinal direction, and the exposed portions 31 adjacent in the width direction. Are arranged so as to be substantially parallel to the width direction. This embodiment respond | corresponds to the arrangement pattern of the exposed part 31 in the polarizing film laminated body 100 shown in FIG. In another embodiment, the exposed portion 31 has a straight line connecting the exposed portions 31 adjacent in the longitudinal direction substantially parallel to the longitudinal direction, and the exposed portions adjacent in the width direction. connecting straight line, it is arranged to have a predetermined angle theta _W with respect to the width direction (not shown). In yet another embodiment, the exposed portion 31 has an exposure in which a straight line connecting the adjacent exposed portions in the longitudinal direction has a predetermined angle θ _L with respect to the longitudinal direction, and adjacent in the width direction. The straight lines connecting the portions are arranged so as to have a predetermined angle θ _W with respect to the width direction (not shown). The θ _L and / or θ _W is preferably more than 0 ° and not more than ± 10 °. Here, “±” means to include both clockwise and counterclockwise directions with respect to the reference direction (long direction or width direction).

  As long as the shape of the exposed portion 31 in plan view (the shape seen from one side of the polarizing film laminate 100) does not adversely affect the camera performance of the image display device using the polarizer, any appropriate shape is adopted. Can be done.

A-2. Second surface protective layer (whole structure)
FIG. 3A is a schematic cross-sectional view of a second surface protective layer used in one embodiment of the present invention. The second surface protective layer 10 typically includes a resin film 11 and an adhesive layer 12 provided on one side of the resin film 11.

  As shown to FIG. 3B, the separator 13 can be temporarily attached to the adhesive layer 12 so that peeling is possible. By having the said structure, while protecting an adhesive layer until actual use, roll formation becomes possible.

  The second surface protective layer 10 can be impermeable. In this specification, the second surface protective layer being impermeable means that the liquid is not allowed to penetrate from the resin film side of the second surface protective layer to the pressure-sensitive adhesive layer side.

  The second surface protective layer 10 is typically elongated. The second surface protective layer 10 can be wound into a roll.

(Resin film)
The resin film 11 can function as a base material for the second surface protective layer 10. Examples of the resin film forming material include olefin resins such as polyethylene and polypropylene, ester resins such as polyethylene terephthalate resin, cycloolefin resins such as norbornene resin, polyamide resins, polycarbonate resins, and copolymers thereof. Examples thereof include resins. Preferred is an olefin resin (particularly polyethylene). Olefin resins are inexpensive and have the advantage that moderate stiffness is imparted to the second surface protective layer.

  The thickness of the resin film is typically 20 μm to 250 μm, preferably 30 μm to 150 μm.

The elastic modulus of the resin film is preferably 0.2 kN / mm ^{2 to} 4.8 kN / mm ² . If the elastic modulus of the resin film is in such a range, there is an advantage that the resin film is not easily deformed even when tension is applied during transportation and / or bonding, and various types of materials can be used. The elastic modulus is measured according to JIS K 6781.

  The tensile elongation of the resin film is preferably 90% to 320%. If the tensile elongation of the resin film is in such a range, there is an advantage that it is difficult to break during transportation. The tensile elongation is measured according to JIS K 6781.

(Adhesive layer)
Arbitrary appropriate adhesives can be employ | adopted as an adhesive which forms an adhesive layer. Examples of the base resin for the pressure-sensitive adhesive include acrylic resins, styrene resins, and silicone resins. Acrylic resins are preferred from the viewpoints of chemical resistance, adhesion for preventing the treatment liquid from entering during immersion, freedom in the adherend, and the like. Examples of the crosslinking agent that can be included in the pressure-sensitive adhesive include isocyanate compounds, epoxy compounds, and aziridine compounds. The pressure-sensitive adhesive may contain, for example, a silane coupling agent. The formulation of the pressure-sensitive adhesive can be appropriately set according to the purpose.

  The thickness of the pressure-sensitive adhesive layer is preferably 5 μm to 60 μm, more preferably 5 μm to 30 μm. If the thickness is too thin, the adhesiveness becomes insufficient, and bubbles or the like may enter the adhesive interface. If the thickness is too thick, problems such as sticking out of the adhesive easily occur.

(separator)
The separator 13 has a function as a protective material that protects the second surface protective layer (adhesive layer) until practical use. Moreover, a 2nd surface protective layer can be favorably wound up by roll shape by using a separator. As the separator, for example, a plastic (for example, polyethylene terephthalate (PET), polyethylene, polypropylene) film, non-woven fabric or surface coated with a release agent such as a silicone release agent, a fluorine release agent, or a long-chain alkyl acrylate release agent For example, paper. Arbitrary appropriate thickness can be employ | adopted for the thickness of a separator according to the objective. The thickness of the separator is, for example, 10 μm to 100 μm.

A-3. Polarizer The polarizer 30 is typically composed of a resin film. The resin film is typically a polyvinyl alcohol-based resin (hereinafter referred to as “PVA-based resin”) film containing a dichroic substance.

  Examples of the dichroic substance include iodine and organic dyes. These may be used alone or in combination of two or more. Preferably, iodine is used. For example, when a non-polarizing part is formed by decoloring by chemical treatment, the iodine complex contained in the resin film (polarizer) is appropriately reduced, so that the non-polarizing part has characteristics suitable for use in a camera part. It is because it can form.

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

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

  The polarizer (excluding the non-polarized part) preferably exhibits absorption dichroism at any wavelength of 380 nm to 780 nm. The single transmittance (Ts) of the polarizer (excluding the non-polarized part) is preferably 39% or more, more preferably 39.5% or more, still more preferably 40% or more, and particularly preferably 40.5% or more. . The theoretical upper limit of the single transmittance is 50%, and the practical upper limit is 46%. Further, the single transmittance (Ts) is a Y value measured with a 2 degree visual field (C light source) of JIS Z8701 and corrected for visibility, for example, using a microspectroscopic system (Lambda Vision, LVmicro) Can be measured. The degree of polarization of the polarizer (excluding the non-polarized part) is preferably 99.9% or more, more preferably 99.93% or more, and further preferably 99.95% or more.

  The thickness of the polarizer can be set to any appropriate value. The thickness is preferably 30 μm or less, more preferably 25 μm or less, still more preferably 20 μm or less, and particularly preferably less than 10 μm. On the other hand, the thickness is preferably 0.5 μm or more, more preferably 1 μm or more. With such a thickness, a polarizer having excellent durability and optical characteristics can be obtained. Moreover, a non-polarizing part can be formed favorably, so that thickness is thin. For example, when forming a non-polarization part by decoloring by a chemical process, the contact time of a process liquid and a resin film (polarizer) can be shortened.

  The absorption axis of the polarizer can be set in any appropriate direction depending on the purpose. The direction of the absorption axis may be, for example, the long direction or the width direction. A polarizer having an absorption axis in the longitudinal direction has an advantage of excellent manufacturing efficiency. For example, a polarizer having an absorption axis in the width direction has an advantage that it can be laminated with a retardation film having a slow axis in the longitudinal direction and a so-called roll-to-roll. In this specification, “roll-to-roll” refers to laminating the rolls in the same long direction while conveying a roll-shaped film.

  A single film may be sufficient as the resin film (typically PVA-type resin film) which comprises the said polarizer, and the resin layer (typically PVA-type resin formed on the resin base material) Layer). Hereinafter, the case where a polarizer is a PVA-type resin layer formed on the resin base material is demonstrated concretely. In addition, when a polarizer is a single PVA-type resin film, since a polarizer can be produced by the method well-known and used in this industry, detailed description is abbreviate | omitted.

A-4. First surface protective layer The first surface protective layer 40 typically includes a resin film and a pressure-sensitive adhesive layer provided on one side of the resin film.

  The first surface protective layer 40 has an opening. The first surface protective layer 40 typically has openings 41, 41... Arranged in a predetermined pattern. The position where the opening is provided may correspond to the position where the exposed part (non-polarized part) is formed.

  The opening may have any suitable shape. The shape of the opening corresponds to the shape of the exposed portion (non-polarized portion) formed in plan view. The opening is formed by, for example, mechanical punching or removal of a predetermined portion.

  The resin film and the pressure-sensitive adhesive layer of the first surface protective layer can adopt the same materials and physical properties (for example, thickness and elastic modulus) as those of the resin film and the pressure-sensitive adhesive layer of the second surface protective layer, respectively.

A-5. Protective film Examples of the material for forming the protective film 20 include cellulose resins such as diacetyl cellulose and triacetyl cellulose, (meth) acrylic resins, cycloolefin resins, olefin resins such as polypropylene, and polyethylene terephthalate resins. Examples thereof include ester resins, polyamide resins, polycarbonate resins, and copolymer resins thereof. The thickness of the protective film is preferably 10 μm to 100 μm.

  The protective film may have an optical compensation function (that is, may have an appropriate refractive index ellipsoid, an in-plane retardation, and a thickness direction retardation depending on the purpose). The protective film is typically laminated on the polarizer via an adhesive layer (specifically, an adhesive layer or an adhesive layer). The adhesive layer is typically formed of a PVA adhesive or an activated energy ray curable adhesive. The pressure-sensitive adhesive layer is typically formed of an acrylic pressure-sensitive adhesive.

A-6. Others Although not shown, the polarizing film laminate of the present invention may further include any appropriate optical functional layer depending on the purpose. Representative examples of the optical functional layer include a retardation film (optical compensation film) and a surface treatment layer.

A-7. Use of Polarizing Film Laminate The polarizing film laminate of the present invention can be used for production of a polarizer having a non-polarizing part (typically, a long polarizer). The production of a polarizer having a non-polarizing part will be described in detail in Section C below.

B. Manufacturing Method of Polarizing Film Laminate FIG. 4 is a schematic perspective view illustrating a manufacturing method of a polarizing film laminate according to one embodiment of the present invention. The method for producing a polarizing film laminate of the present invention includes a step of laminating the second surface protective layer 10 on one side of the polarizer 30 and a side of the polarizer 30 on which the second surface protective layer 10 is laminated. Laminating the first surface protective layer 40. In the illustrated example, before laminating the first surface protective layer 40 on the polarizing plate, the laminate of the protective film 20 / second surface protective layer 10 is arranged so that the protective film 20 is on the polarizer 30 side. Laminated on one side of 30. By laminating the second surface protective layer before laminating the first surface protective layer on the polarizer or polarizing plate, the opening formed in the first surface protective layer is transferred to the polarizer as a mark during winding. Has the advantage that it is prevented. Furthermore, when a polarizing film laminated body is provided with a protective film, it has the advantage that damage to a protective film is prevented. The aspect of laminating the second surface protective layer before laminating the first surface protective layer can be suitably applied, for example, when the polarizer is a PVA-based resin layer formed on a resin substrate. The above lamination is typically bonding by roll-to-roll.

  When the polarizer 30 is a resin layer formed on a resin base material, the resin base material can be peeled off. In one embodiment, the second surface protective layer 10 is laminated on the surface of the polarizer of the resin substrate / polarizer laminate, and then the resin substrate is peeled off. In another embodiment, the protective film 20 is laminated on the polarizer surface of the resin substrate / polarizer laminate, and then the resin substrate is peeled off. In yet another embodiment, the laminate of the protective film 20 / second surface protective layer 10 is laminated on the polarizer surface of the resin substrate / polarizer laminate, and then the resin substrate is peeled off.

  In one embodiment, a 2nd surface protection layer is bonded together to a polarizer via an adhesive layer. When the protective film 20 is provided, the second surface protective layer is bonded to the protective film via the pressure-sensitive adhesive layer. In the illustrated example, the second surface protective layer 10 is bonded to the protective film 20 to form a protective film 20 / second surface protective layer 10 laminate, and the laminate is attached to the polarizer. The second surface protective layer 10 is typically bonded so as to be peelable. By using the second surface protective layer, the polarizer or the polarizing plate (polarizer / protective film) can be appropriately protected in the decoloring treatment described later. As a result, when manufacturing a polarizer having a non-polarizing part, it is possible to continuously immerse the polarizing film laminate in a treatment liquid while roll transporting, so that the processing efficiency of various selective treatments is extremely high. Can be high. Furthermore, it is possible to realize a low-cost, high-yield, high-productivity manufacturing of a polarizer suitable for multifunctional and high-functionality electronic devices such as image display devices.

  The first surface protective layer 40 is typically bonded to the polarizer 30 so as to be peelable. In the example of illustration, the elongate 1st surface protective layer 40 which has the opening parts 41, 41 ... in the polarizer 30 side of the elongate laminated body of polarizer 30 / protective film 20 / 2nd surface protective layer 10 is shown. Are bonded together by roll-to-roll. By using the first surface protective layer having the opening, the exposed portion (non-polarized portion) can be more favorably formed.

  As described above, a polarizing film laminate can be produced. A polarizing film laminated body may be used for manufacture of the polarizer which has a non-polarizing part, for example.

C. The manufacturing method of the polarizer which has a non-polarizing part The manufacturing method of the polarizer which has a non-polarizing part of this invention prepares the said polarizing film laminated body, and immerses the said polarizing film laminated body in a process liquid. And partially decolorizing the polarizer to form a non-polarizing part.

  The said polarizing film laminated body is typically prepared by laminating | stacking the polarizer 30, the 2nd surface protective layer 10, the 1st surface protective layer 40, and the protective film 20 as needed. The second surface protective layer may be laminated on the polarizer or the polarizing plate simultaneously with the first surface protective layer, may be laminated before the first surface protective layer is laminated, or the first surface protective layer is laminated. You may laminate | stack later. Preferably, the said polarizing film laminated body is prepared by the manufacturing method of the polarizing film laminated body of this invention demonstrated by B term.

  Next, by immersing the polarizing film laminate in the treatment liquid, the polarizer is partially decolored to form a non-polarizing part. Typically, the exposed portion is decolorized. As shown in FIG. 5, the decoloring treatment may further include removing the treatment liquid, contacting the polarizing film laminate with the acidic solution, and removing the acidic solution as necessary. This will be specifically described below. By immersing the polarizing film laminate in the treatment liquid and performing the decoloring treatment, the decoloring treatment can be performed while conveying the polarizing film laminate as shown in FIG. 5, so that the production efficiency is remarkably improved.

  As described above, immersion is possible by using the second surface protective layer. Specifically, only the exposed part of the polarizing film laminate is in contact with the treatment liquid by immersing the polarizing film laminate in the treatment liquid. For example, when the polarizer contains iodine as a dichroic substance, the exposed portion and the treatment liquid are brought into contact with each other to reduce the iodine concentration in the exposed portion. Can be formed. Thus, according to the present embodiment, the non-polarized portion can be selectively formed on the exposed portion with very high manufacturing efficiency without complicated operations. When iodine remains in the polarizer, even if the iodine complex is destroyed to form a non-polarizing part, the iodine complex is formed again with the use of the polarizer, and the non-polarizing part has the desired characteristics. There is a risk that it will disappear. In the present embodiment, iodine itself is removed from the polarizer (substantially the non-polarizing part) by removing the treatment liquid described later. As a result, it is possible to prevent a change in the characteristics of the non-polarizing part accompanying the use of the polarizer.

  The formation of the non-polarizing part by the treatment liquid will be described in more detail. After contact with the exposed portion, the processing liquid penetrates into the exposed portion. The polarizing performance of the exposed portion is substantially lost by the treatment liquid. For example, when the treatment liquid is a basic solution, the iodine complex contained in the exposed portion is reduced by the base contained in the basic solution to become iodine ions. When the iodine complex is reduced to iodine ions, the polarization performance of the exposed portion is substantially lost, and a non-polarized portion is formed in the exposed portion. Moreover, the transmittance | permeability of an exposed part improves by reduction | restoration of an iodine complex. Iodine that has become iodine ions moves from the exposed portion into the solvent of the treatment liquid. As a result, the removal of the treatment liquid described later removes iodine ions from the portion together with the treatment liquid. In this way, a non-polarizing portion is selectively formed in the exposed portion, and the non-polarizing portion is stable without change over time. In addition, the material, thickness and mechanical properties of the second surface protective layer (more specifically, the resin film and the pressure-sensitive adhesive layer), the concentration of the treatment liquid, and the immersion time of the polarizing film laminate in the treatment liquid are adjusted. By doing so, it is possible to prevent the treatment liquid from penetrating to an undesired portion (as a result, a non-polarizing portion is formed in an undesired portion).

  The treatment liquid is typically a basic solution. Any appropriate basic compound can be used as the basic compound contained in the basic solution. Examples of basic compounds include hydroxides of alkali metals such as sodium hydroxide, potassium hydroxide and lithium hydroxide, hydroxides of alkaline earth metals such as calcium hydroxide, inorganic alkali metal salts such as sodium carbonate, acetic acid Organic alkali metal salts such as sodium, aqueous ammonia and the like can be mentioned. The basic compound contained in the basic solution is preferably an alkali metal hydroxide, more preferably sodium hydroxide, potassium hydroxide, or lithium hydroxide. By using a basic solution containing an alkali metal hydroxide, the iodine complex can be ionized efficiently, and a non-polarizing part can be formed more easily. These basic compounds may be used alone or in combination of two or more.

  Any appropriate solvent can be used as the solvent of the basic solution. Specific examples include water, alcohols such as ethanol and methanol, ethers, benzene, chloroform, and mixed solvents thereof. Since iodine ions migrate to the solvent satisfactorily and iodine ions can be easily removed in the subsequent removal of the basic solution, the solvent is preferably water or alcohol.

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

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

  The treatment liquid can be removed by any appropriate means as necessary after contact with the exposed portion. Specific examples of the method for removing the treatment liquid include washing, wiping removal with a waste cloth, suction removal, natural drying, heat drying, air drying, reduced pressure drying, and the like, and washing is preferable. This is because the processing liquid removal performance is excellent, a complicated apparatus is not required, and the manufacturing efficiency is excellent. Examples of the liquid used for washing include water (pure water), alcohols such as methanol and ethanol, acidic aqueous solutions, and mixed solvents thereof. Preferably, it is water. The cleaning is typically performed while conveying the polarizing film laminate as shown in FIG. Washing may be performed multiple times. The drying temperature when removing the treatment liquid by drying is, for example, 20 ° C to 100 ° C.

  If necessary, the polarizing film laminate (substantially the exposed portion) in contact with the treatment liquid can be further brought into contact with the acidic solution. The contact between the polarizing film laminate and the acidic solution can be performed by any appropriate means. As in the case of contact with the treatment liquid, immersion is preferred. By making it contact with an acidic solution, the process liquid which remains in a non-polarizing part can be removed to a further favorable level. Moreover, the dimensional stability and durability of a non-polarizing part can improve by making it contact with an acidic solution. The contact with the acidic solution may be performed after removing the treatment liquid or may be performed without removing the treatment liquid.

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

  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 portion) and the acidic solution depends on the thickness of the resin film (polarizer), the type of acidic compound contained in the acidic solution used, and the concentration of the acidic compound. For example, the time is 5 seconds to 30 minutes. As needed, after making a polarizing film laminated body and an acidic solution contact, you may remove by wiping off etc. immediately.

  The acidic solution can be removed by any appropriate means as necessary after contact with the exposed portion. As in the case of removing the treatment liquid, washing is preferred. Examples of the liquid used for washing include water (pure water), alcohols such as methanol and ethanol, acidic aqueous solutions, and mixed solvents thereof. Preferably, it is water. The cleaning is typically performed while conveying the polarizing film laminate as shown in FIG. Washing may be performed multiple times.

  When removing an acidic solution in this embodiment by washing | cleaning, the polarizing film laminated body after acidic solution removal is used for washing | cleaning liquid removal and drying as needed (not shown). The removal of the cleaning liquid (typically water) can be performed by any suitable means. Specific examples include blowing away with a blower, passing the polarizing film laminate through a sponge roll, and combinations thereof. By removing the cleaning liquid, the cleaning liquid remaining in the opening of the first surface protective layer can be removed to a better level, so that the adverse effect of the remaining cleaning liquid on the polarizer can be prevented. Drying can be performed, for example, by conveying the polarizing film laminate in an oven. The drying temperature is, for example, 20 ° C. to 100 ° C., and the drying time is, for example, 5 seconds to 600 seconds.

  After the decolorization (eg, after the washing), the first surface protective layer and the second surface protective layer can be removed.

  As described above, the non-polarizing portion can be formed on the long polarizer with a predetermined arrangement pattern. A polarizer having a non-polarizing part can be used, for example, in an image display device having a camera part.

  Typically, the non-polarizing portion is disposed at a position corresponding to the camera portion of the image display device when the polarizer is cut to a predetermined size in order to attach the polarizer to the image display device of a predetermined size. Therefore, when only one size polarizer is cut from one long polarizer, the non-polarizing portions can be arranged at substantially equal intervals in both the long direction and the width direction. With such a configuration, it is easy to control the cutting of the polarizer to a predetermined size in accordance with the size of the image display device, and the yield can be improved. Furthermore, since the position of the non-polarizing part can be set accurately, the position of the non-polarizing part in the obtained polarizer of a predetermined size can be controlled well. As a result, since the variation in the position of the non-polarizing portion for each obtained polarizer of a predetermined size is reduced, it is possible to obtain a polarizer of a predetermined size with no quality variation. When cutting a plurality of size polarizers from one long polarizer, the interval between the non-polarizing portions in the long direction and / or the width direction may be changed according to the size of the polarizer to be cut. it can. As described above, the non-polarizing portion can be formed with a desired arrangement pattern by appropriately setting the arrangement pattern of the openings in the first surface protective layer.

  The transmittance of the non-polarizing part (for example, the transmittance measured with light having a wavelength of 550 nm at 23 ° C.) is preferably 50% or more, more preferably 60% or more, further preferably 75% or more, Particularly preferably, it is 90% or more. With such transmittance, desired transparency as a non-polarizing portion can be ensured. As a result, when the polarizer is arranged so that the non-polarizing part corresponds to the camera part of the image display device, it is possible to prevent an adverse effect on the photographing performance of the camera.

  Any appropriate shape can be adopted as the planar view shape of the non-polarizing part as long as it does not adversely affect the camera performance of the image display device using the polarizer. By appropriately setting the shape of the opening in the first surface protective layer, a non-polarizing portion having a desired planar view shape can be formed.

  The polarizing film laminate of the present invention is suitably used when producing a polarizing plate having a partially polarizing performance used in an image display device in which an internal electronic component such as a camera is mounted.

DESCRIPTION OF SYMBOLS 10 2nd surface protective layer 11 Resin film 12 Adhesive layer 20 Protective film 30 Polarizer 31 Exposed part (non-polarizing part)
40 First surface protective layer 100 Polarized film laminate

Claims (7)

A long polarizing film laminate,
A polarizer,
A first surface protective layer having an opening, which is detachably disposed on one side of the polarizer;
A second surface protective layer that is detachably disposed on the other side of the polarizer,
An exposed portion where the polarizer is exposed is defined by the opening,
The exposed portions are arranged in the longitudinal direction and / or the width direction of the elongated polarizing film laminate at intervals corresponding to the size of the polarizer to be cut , and have a substantially circular plan view shape. ,
The first surface protective layer and the second surface protective layer each include a resin film and an adhesive layer, each resin film has a thickness of 20 μm to 250 μm, and an elastic modulus of 0.2 kN / mm ² to 4.8 kN / mm ²
Polarized film laminate. A protective film disposed between the polarizer and the second surface protective layer;
The second surface protective layer is bonded to the protective film;
The polarizing film laminated body of Claim 1. The second surface protective layer is disposed on the outermost side on one side of the polarizer,
The polarizing film laminated body of Claim 1 or 2. Laminating the second surface protective layer on one side of the polarizer by roll-to-roll;
Laminating the first surface protective layer by roll-to-roll on the other side of the polarizer on which the second surface protective layer is laminated,
The manufacturing method of the polarizing film laminated body of any one of Claims 1-3. The polarizing film laminate according to any one of claims 1 to 3 is obtained by the method according to claim 4, and the polarizer is partially immersed by immersing the polarizing film laminate in a treatment liquid. A method for producing a polarizer having a non-polarizing part.   The manufacturing method according to claim 5, further comprising removing the second surface protective layer after the decolorization. The polarizing film laminate further comprises a protective film disposed between the polarizer and the second surface protective layer,
The polarizing film laminate is formed by laminating a laminate of the protective film and the second surface protective layer on one side of the polarizer by roll-to-roll so that the protective film is on the polarizer side. Is obtained by
The lamination is performed before immersing the polarizing film laminate in a treatment liquid.
The manufacturing method of Claim 5 or 6.

Images