WO2019202987A1 - Window glare prevention film - Google Patents

Window glare prevention film Download PDF

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Publication number
WO2019202987A1
WO2019202987A1 PCT/JP2019/014781 JP2019014781W WO2019202987A1 WO 2019202987 A1 WO2019202987 A1 WO 2019202987A1 JP 2019014781 W JP2019014781 W JP 2019014781W WO 2019202987 A1 WO2019202987 A1 WO 2019202987A1
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Prior art keywords
polarizer
film
window
retardation
layer
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PCT/JP2019/014781
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French (fr)
Japanese (ja)
Inventor
将寛 八重樫
義浩 大西
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日東電工株式会社
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Publication of WO2019202987A1 publication Critical patent/WO2019202987A1/en

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    • E—FIXED CONSTRUCTIONS
    • E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06B—FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES
    • E06B9/00—Screening or protective devices for wall or similar openings, with or without operating or securing mechanisms; Closures of similar construction
    • E06B9/24—Screens or other constructions affording protection against light, especially against sunshine; Similar screens for privacy or appearance; Slat blinds
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements

Definitions

  • the present invention relates to an antiglare film for windows.
  • the present invention has been made to solve the above-described conventional problems, and the object of the present invention is for a window that can suppress glare due to reflected light of incident sunlight and can maintain internal brightness.
  • the object is to provide an antiglare film.
  • the antiglare film for windows is an antiglare film for windows that is bonded to a window.
  • This window antiglare film includes a polarizer, and is bonded to the window such that the transmission axis of the polarizer is substantially perpendicular to the vibration direction of reflected sunlight incident on the window.
  • the polarizer is an absorptive polarizer.
  • the polarization degree of the polarizer is 99.0% or more.
  • the polarizer is a reflective polarizer.
  • the antiglare film for windows further includes a retardation layer having an in-plane retardation Re (550) of 100 nm to 200 nm, which is disposed on the opposite side of the polarizer from the window.
  • the angle formed by the slow axis of the retardation layer and the transmission axis of the polarizer is 38 ° to 52 °.
  • the antiglare film for windows further includes another retardation layer having an in-plane retardation Re (550) of 180 nm to 320 nm, which is disposed on the window side of the polarizer.
  • the angle formed between the slow axis of another retardation layer and the transmission axis of the polarizer is 38 ° to 52 °.
  • a polarizer is introduced into a film to be bonded to a window so that the transmission axis of the polarizer is substantially orthogonal to the vibration direction of reflected sunlight incident on the window.
  • the expressions “substantially vertical”, “substantially orthogonal” and “substantially orthogonal” include the case where the angle between the two directions is 90 ° ⁇ 10 °, preferably 90 °. ⁇ 7 °, more preferably 90 ° ⁇ 5 °.
  • the expressions “substantially parallel” and “substantially parallel” include the case where the angle between two directions is 0 ° ⁇ 10 °, preferably 0 ° ⁇ 7 °, more preferably 0 ° ⁇ 5 °.
  • the term “vertical”, “orthogonal” or “parallel” may include a substantially vertical, orthogonal or substantially parallel state.
  • the said angle includes both clockwise rotation and counterclockwise rotation with respect to a reference direction.
  • FIG. 1 is a schematic cross-sectional view of a window antiglare film according to one embodiment of the present invention.
  • the window antiglare film 100 in the illustrated example includes a polarizer 10.
  • the polarizer may be an absorptive polarizer or a reflective polarizer. If necessary, a protective film (not shown) may be provided on one side or both sides of the polarizer.
  • the transmission axis of the polarizer is substantially orthogonal to the vibration direction of the reflected sunlight that enters the window. It is configured. More details are as follows.
  • the reflected light of sunlight by a surface (for example, a lake surface or a road) in a direction substantially parallel to the ground is a direction (typically, a horizontal direction) whose vibration direction is substantially parallel to the ground.
  • the reflected light of sunlight from a surface in a direction substantially perpendicular to the ground is a direction in which the vibration direction is substantially perpendicular to the ground (typically, the vertical direction). It is. Therefore, when the ground or horizontal plane is dominant in the external scenery (when the surroundings of the building or vehicle are, for example, a lakeside, coast, or plain), the direction of vibration of the reflected sunlight is controlled by the horizontal direction.
  • the transmission axis of the polarizer can typically be arranged in a direction substantially parallel to the vertical direction; in an external landscape, the plane perpendicular to the ground or horizontal plane is dominant In some cases (when the surroundings of the building or vehicle are, for example, an urban area where the building is forested), the vertical direction is dominant in the oscillation direction of the reflected solar light, so the transmission axis of the polarizer is representative. May be arranged in a direction substantially parallel to the horizontal direction.
  • the external landscape includes a certain percentage of the ground or horizontal plane and a plane perpendicular to the ground or horizontal plane (for example, a certain percentage of lake or sea level and buildings are included).
  • the transmission axis of the polarizer can typically be arranged at a predetermined angle (for example, 45 °) corresponding to the ratio with respect to the horizontal or vertical direction.
  • a predetermined angle for example, 45 °
  • the antiglare film for windows according to the embodiment of the present invention suppresses the reflected light of sunlight from entering the inside, and thus suppresses the glare caused by such reflected light, and as a result, the external The beauty and visibility of the scenery can be maintained.
  • the antiglare film for windows according to the embodiment of the present invention can selectively block the reflected light of sunlight that causes glare, unlike a general light shielding film, so that the internal brightness is maintained. Can do.
  • the window antiglare film 100 may further include a retardation layer 20 on one side of the polarizer as shown in the illustrated example.
  • the retardation layer 20 can be typically disposed on the opposite side (inside) of the polarizer window.
  • the in-plane retardation Re (550) of the retardation layer 20 is preferably 100 nm to 200 nm.
  • the angle formed by the slow axis of the retardation layer 20 and the transmission axis of the polarizer 10 is preferably 38 ° to 52 °.
  • the antiglare film 100 for windows may further include another retardation layer 30 on the other side of the polarizer as shown in the illustrated example.
  • the other retardation layer 30 can be typically disposed on the window side (external side) of the polarizer when the window antiglare film is bonded to the window.
  • Another retardation layer 30 has an in-plane retardation Re (550) of preferably 180 nm to 320 nm.
  • the angle formed between the slow axis of the other retardation layer 30 and the transmission axis of the polarizer 10 is preferably 38 ° to 52 °.
  • the operability of bonding to the window can be significantly improved. More details are as follows.
  • the polarizer is often in a direction in which the transmission axis is orthogonal to the longitudinal direction of the roll due to the production method. Therefore, according to such bonding, the transmission axis of the polarizer is in a direction substantially parallel to the horizontal direction. Therefore, if you want to arrange the transmission axis of the polarizer so that it is substantially parallel to the vertical direction (when the ground or horizontal plane is dominant in the external scenery), cut out the film and adjust the transmission axis direction. And must be attached to the window.
  • phase difference layer 20 and the other phase difference layer 30 are optional components, and either one or both of them can be omitted depending on the purpose and the position of the window (substantially the external scenery).
  • each slow axis direction is orthogonal or parallel.
  • An absorptive polarizer (hereinafter sometimes simply referred to as a polarizer) is typically a resin film in which a dichroic substance (for example, iodine) is adsorbed and oriented.
  • the resin film forming the absorption polarizer may be a single layer resin film or a laminate of two or more layers.
  • the absorption polarizer composed of a single-layer resin film include high hydrophilicity such as polyvinyl alcohol (PVA) film, partially formalized PVA film, and ethylene / vinyl acetate copolymer partially saponified film.
  • PVA polyvinyl alcohol
  • molecular films that have been dyed and stretched with dichroic substances such as iodine and dichroic dyes
  • polyene-based oriented films such as PVA dehydrated products and polyvinyl chloride dehydrochlorinated products It is done.
  • a polarizer obtained by dyeing a PVA film with iodine and uniaxially stretching is used because of excellent optical properties.
  • the dyeing with iodine is performed, for example, by immersing a PVA film in an aqueous iodine solution.
  • the stretching ratio of the uniaxial stretching is preferably 3 to 7 times.
  • the stretching may be performed after the dyeing treatment or may be performed while dyeing. Moreover, you may dye
  • the PVA film is subjected to swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like. For example, by immersing the PVA film in water and washing it before dyeing, not only can the surface of the PVA film be cleaned of dirt and anti-blocking agents, but the PVA film can be swollen to cause uneven staining. Can be prevented.
  • the absorption polarizer obtained using the laminate a laminate of a resin substrate and a PVA resin layer (PVA resin film) laminated on the resin substrate, or a resin substrate and Examples thereof include a polarizer obtained by using a laminate with a PVA-based resin layer formed by coating on the resin base material.
  • a polarizer obtained by using a laminate of a resin base material and a PVA resin layer applied and formed on the resin base material may be obtained by, for example, applying a PVA resin solution to a resin base material and drying it.
  • a PVA-based resin layer is formed thereon to obtain a laminate of a resin base material and a PVA-based resin layer; the laminate is stretched and dyed to make the PVA-based resin layer a polarizer; obtain.
  • stretching typically includes immersing the laminate in an aqueous boric acid solution and stretching.
  • the stretching may further include, if necessary, stretching the laminate in the air at a high temperature (for example, 95 ° C. or higher) before stretching in the aqueous boric acid solution.
  • the obtained resin base material / polarizer laminate may be used as it is (that is, the resin base material may be used as a protective layer of the polarizer), and the resin base material is peeled from the resin base material / polarizer laminate.
  • Any appropriate protective layer according to the purpose may be laminated on the release surface. Details of a method for manufacturing such a polarizer are described in, for example, Japanese Patent Application Laid-Open No. 2012-73580. This publication is incorporated herein by reference in its entirety.
  • the absorptive polarizer preferably exhibits absorption dichroism at any wavelength between 380 nm and 780 nm.
  • the single transmittance of the absorptive polarizer is preferably 40.0% to 46.5%, more preferably 40.0% to 43.0%, and further preferably 40.5% to 42.5%. %.
  • the degree of polarization of the absorbing polarizer is preferably 99.0% or more, more preferably 99.5% or more, and further preferably 99.9% or more.
  • the single transmittance is a Y value obtained by correcting the visibility with a two-degree field of view (C light source) of JIS Z 8701-1982.
  • the thickness of the absorbing polarizer can be, for example, 1 ⁇ m to 80 ⁇ m.
  • the reflective polarizer has a function of transmitting polarized light in a specific polarization state (polarization direction) and reflecting light in other polarization states.
  • the reflective polarizer may be a linearly polarized light separation type or a circularly polarized light separation type.
  • a linearly polarized light separation type reflective polarizer will be briefly described.
  • Examples of the circularly polarized light separation type reflective polarizer include a laminate of a film in which cholesteric liquid crystal is fixed and a ⁇ / 4 plate.
  • FIG. 2 is a schematic perspective view of an example of a reflective polarizer.
  • the reflective polarizer is a multilayer laminate in which layers A having birefringence and layers B having substantially no birefringence are alternately laminated.
  • the total number of layers in such a multilayer stack can be 50-1000.
  • the refractive index nx in the x-axis direction of the A layer is larger than the refractive index ny in the y-axis direction, and the refractive index nx in the x-axis direction and the refractive index ny in the y-axis direction of the B layer are substantially the same. is there.
  • the difference in refractive index between the A layer and the B layer is large in the x-axis direction and is substantially zero in the y-axis direction.
  • the x-axis direction becomes the reflection axis
  • the y-axis direction becomes the transmission axis.
  • the refractive index difference in the x-axis direction between the A layer and the B layer is preferably 0.2 to 0.3.
  • the x-axis direction corresponds to the extending direction of the reflective polarizer in the reflective polarizer manufacturing method.
  • the reflective polarizer may include a reflective layer R as the outermost layer as shown in the example of the drawing.
  • the A layer is preferably made of a material that develops birefringence by stretching.
  • Representative examples of such materials include naphthalene dicarboxylic acid polyesters (for example, polyethylene naphthalate), polycarbonates, and acrylic resins (for example, polymethyl methacrylate). Polyethylene naphthalate is preferred.
  • the B layer is preferably made of a material that does not substantially exhibit birefringence even when stretched.
  • a typical example of such a material is a copolyester of naphthalenedicarboxylic acid and terephthalic acid.
  • the reflective polarizer for example, the one described in JP-T-9-507308 can be used.
  • a commercially available product may be used as it is, or a commercially available product may be used after secondary processing (for example, stretching).
  • 3M company brand name DBEF and 3M company brand name APF are mentioned, for example.
  • the protective film can be typically used when the polarizer is an absorptive polarizer.
  • any appropriate resin film that can be used as a protective film for a polarizer can be adopted.
  • the material as the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyester-based, polyvinyl alcohol-based, polycarbonate-based, polyamide-based, polyimide-based, polyethersulfone-based, and polysulfone-based materials.
  • transparent resins such as polystyrene, polynorbornene, polyolefin, (meth) acryl, and acetate.
  • thermosetting resins such as (meth) acrylic, urethane-based, (meth) acrylurethane-based, epoxy-based, and silicone-based or ultraviolet curable resins are also included.
  • a glassy polymer such as a siloxane polymer is also included.
  • a polymer film described in JP-A-2001-343529 (WO01 / 37007) can also be used.
  • a resin composition containing a thermoplastic resin having a substituted or unsubstituted imide group in the side chain and a thermoplastic resin having a substituted or unsubstituted phenyl group and nitrile group in the side chain for example, a resin composition having an alternating copolymer of isobutene and N-methylmaleimide and an acrylonitrile / styrene copolymer can be mentioned.
  • the polymer film can be, for example, an extruded product of the resin composition.
  • the hard coating treatment, antireflection treatment, antisticking treatment, Surface treatment such as anti-glare treatment may be applied.
  • the protective film is preferably optically isotropic.
  • “optically isotropic” means that the in-plane retardation Re (550) is 0 nm to 10 nm and the thickness direction retardation Rth (550) is ⁇ 10 nm to +10 nm.
  • Re ( ⁇ ) is an in-plane retardation measured with light having a wavelength of ⁇ nm at 23 ° C.
  • Re (550) is an in-plane retardation measured with light having a wavelength of 550 nm at 23 ° C.
  • Rth ( ⁇ ) is a retardation in the thickness direction measured with light having a wavelength of ⁇ nm at 23 ° C.
  • Rth (550) is a retardation in the thickness direction measured with light having a wavelength of 550 nm at 23 ° C.
  • Nx is the refractive index in the direction in which the in-plane refractive index is maximum (ie, the slow axis direction), and “ny” is the direction orthogonal to the slow axis in the plane (ie, the fast axis direction). “Nz” is the refractive index in the thickness direction.
  • the retardation layer 20 has an in-plane retardation Re (550) of preferably 100 nm to 200 nm, more preferably 120 nm to 180 nm, and still more preferably 130 nm to 160 nm as described above.
  • Re in-plane retardation Re
  • the retardation layer preferably exhibits a refractive index characteristic of nx> ny ⁇ nz. Therefore, the retardation layer has a slow axis.
  • the angle formed by the transmission axis of the polarizer 10 and the slow axis of the retardation layer 20 is preferably 38 ° to 52 °, more preferably 42 ° to 48 °, and even more preferably about 45 °. .
  • the Nz coefficient of the retardation layer is preferably 0.9 to 2.5, more preferably 0.9 to 1.5, and still more preferably 0.9 to 1.3.
  • the retardation layer may exhibit reverse dispersion wavelength characteristics in which the retardation value increases with the wavelength of the measurement light, or may exhibit positive wavelength dispersion characteristics in which the retardation value decreases with the wavelength of the measurement light.
  • the phase difference value may exhibit a flat chromatic dispersion characteristic that hardly changes depending on the wavelength of the measurement light.
  • Re (450) / Re (550) is preferably 0.85 or more and less than 1.00, more preferably 0.95 or more and less than 1.00
  • Re (550) / Re (650) is preferably 0.90 or more and less than 1.00, and more preferably 0.95 or more and less than 1.00.
  • Re (450) / Re (550) is preferably 1.00 to 1.15, more preferably 1.00 to 1.
  • Re (550) / Re (650) is preferably 1.00 to 1.10, more preferably 1.00 to 1.05.
  • the thickness of the retardation layer can be set so as to obtain the desired in-plane retardation.
  • the thickness of the retardation layer is preferably 20 ⁇ m to 100 ⁇ m, more preferably 30 ⁇ m to 70 ⁇ m.
  • the retardation layer may be composed of any appropriate resin film that can realize the above characteristics.
  • the resin forming the retardation layer include polyarylate, polyamide, polyimide, polyester, polyaryletherketone, polyamideimide, polyesterimide, polyvinyl alcohol, polyfumaric acid ester, polyethersulfone, polysulfone, norbornene resin, and polycarbonate. Resins, cellulose resins and polyurethanes can be mentioned. These resins may be used alone or in combination.
  • the retardation layer can be obtained by stretching a film formed from these resins under conditions according to the type of resin and the desired characteristics.
  • Another Retardation Layer 30 has an in-plane retardation Re (550) of preferably 180 nm to 320 nm, more preferably 200 nm to 290 nm, and further preferably 230 nm to 280 nm as described above. .
  • Re in-plane retardation Re
  • the thickness of the other retardation layer can be set so as to obtain the desired in-plane retardation.
  • the thickness of the other retardation layer is preferably 20 ⁇ m to 150 ⁇ m, more preferably 40 ⁇ m to 100 ⁇ m.
  • the parallel transmittance (H 0 ) is a transmittance value of a parallel laminated polarizing plate produced by superposing two identical polarizing plates so that their absorption axes are parallel to each other.
  • the orthogonal transmittance (H 90 ) is a value of the transmittance of an orthogonal laminated polarizing plate produced by superposing two identical polarizing plates so that their absorption axes are orthogonal to each other.
  • These transmittances are Y values obtained by correcting the visibility with a two-degree field of view (C light source) of JIS Z 8701-1982.
  • the light shielding film used by the comparative example does not have a polarizer and does not have optical anisotropy, it measured by having piled up two films
  • a glass plate with a film prepared in Examples and Comparative Examples was installed between a luminance meter and an aluminum bat as a substitute for window glass, and the reflected luminance from the water surface was measured through the glass.
  • Outdoor brightness A brightness meter ("LS-150" manufactured by Konica Minolta Co., Ltd .: measurement angle 1 °, measurement area ⁇ 14.4 mm) is installed in a predetermined position and in a predetermined direction in the sunny day. The brightness of the tiled roof of the building can be measured.
  • the glass plate with a film produced in the examples and comparative examples was installed between the luminance meter and the building as a substitute for window glass, and the luminance of the tile roof was measured through the glass.
  • a polymer film composed mainly of polyvinyl alcohol (manufactured by Kuraray, trade name “9P75R (thickness: 75 ⁇ m, average polymerization degree: 2,400, saponification degree 99.9 mol%)”) is immersed in a water bath for 1 minute. While stretching 1.2 times in the transport direction, it is immersed in an aqueous solution having an iodine concentration of 0.3% by weight for 1 minute to dye a film (original length) that is not stretched in the transport direction while being dyed.
  • polyvinyl alcohol manufactured by Kuraray, trade name “9P75R (thickness: 75 ⁇ m, average polymerization degree: 2,400, saponification degree 99.9 mol%)
  • a polarizer (thickness 28 ⁇ m) was produced.
  • Table 1 shows the single transmittance and the degree of polarization of the polarizer.
  • a protective film (TAC film, thickness 40 ⁇ m) was bonded to both sides of the obtained polarizer to obtain a polarizing plate.
  • the obtained polarizing plate was bonded to a glass plate via an adhesive layer (thickness: 23 ⁇ m) to produce a polarizing plate-attached glass plate.
  • Example 2 A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the production conditions of the polarizer were changed and the single transmittance and the degree of polarization were as shown in Table 1. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 3 A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the production conditions of the polarizer were changed and the single transmittance and the degree of polarization were as shown in Table 1. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 4 A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that a reflective polarizer (“APF” manufactured by 3M) was used instead of the polarizing plate.
  • the obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 5 A glass plate with a polarizing plate was obtained in the same manner as in Example 1 except that a retardation film (so-called ⁇ / 4 plate) was bonded to the surface of the protective film disposed on the side opposite to the glass plate of the polarizing plate of Example 1.
  • the retardation film was a stretched film of a polyarylate resin film, and the in-plane retardation Re (550) thereof was 147 nm. Furthermore, the retardation film was bonded so that the angle formed between the slow axis and the absorption axis of the polarizer was 45 °.
  • the obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 6 The retardation film (so-called ⁇ / 2 plate) was bonded to the surface of the protective film disposed on the glass plate side of the polarizing plate of Example 1, and the transmission axis of the polarizer was substantially parallel to the horizontal direction.
  • a glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the polarizing plate and the glass plate were bonded together (so as to be substantially parallel to the vibration direction of the reflected light).
  • the retardation film was a stretched film of a polycarbonate resin film, and the in-plane retardation Re (550) was 270 nm.
  • Example 7 On the surface of the protective film disposed on the glass plate side, the retardation film ( ⁇ / 4 plate) of Example 5 was bonded to the surface of the protective film disposed on the side opposite to the glass plate of the polarizing plate of Example 1. The retardation film ( ⁇ / 2 plate) of Example 6 was bonded, and the transmission axis of the polarizer was substantially parallel to the horizontal direction (substantially with respect to the vibration direction of the reflected light).
  • a glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the polarizing plate and the glass plate were bonded together (in parallel).
  • the ⁇ / 4 plate and the ⁇ / 2 plate were bonded together so that the angle formed between the slow axis and the absorption axis of the polarizer was 45 °.
  • the obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 2 A glass plate with a light-shielding film was produced in the same manner as in Example 1 except that a commercially available light-shielding film (“TSF4518SMK” manufactured by Trusco Nakayama Co., Ltd.) was used instead of the polarizing plate.
  • TSF4518SMK commercially available light-shielding film
  • the said light shielding film did not have optical anisotropy, it bonded together so that a film short side might become a horizontal direction (substantially parallel to the vibration direction of reflected light).
  • the obtained glass plate with a light-shielding film was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 4 A glass plate with a light-shielding film was produced in the same manner as in Example 1 except that a commercially available light-shielding film (“TSF4518TM” manufactured by Trusco Nakayama Co., Ltd.) was used instead of the polarizing plate.
  • TSF4518TM commercially available light-shielding film
  • the said light shielding film did not have optical anisotropy, it bonded together so that a film short side might become a horizontal direction (substantially parallel to the vibration direction of reflected light).
  • the obtained glass plate with a light-shielding film was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • Example 1 except that the polarizing plate is bonded to the glass plate so that the transmission axis of the polarizer is substantially parallel to the horizontal direction (so that it is substantially parallel to the vibration direction of the reflected light).
  • a glass plate with a polarizing plate was produced.
  • the obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
  • the glare-preventing film for windows according to the examples of the present invention can suppress glare caused by incident sunlight reflected light while maintaining internal brightness. Further, as is clear when Examples 1 and 2 are compared with Examples 3 and 4, it can be seen that the effect becomes remarkable by reducing the single transmittance of the polarizer (increasing the degree of polarization).
  • the antiglare film for windows according to the embodiment of the present invention can be suitably used for windows of buildings and vehicles.

Abstract

Provided is a window glare prevention film that is capable of suppressing glare caused by reflected light of sunlight incident on the film and capable of maintaining brightness inside. A window glare prevention film according to an embodiment of the present invention is a film attached to a window. This window glare prevention film includes a polarizer, and is stuck to the window so that the transmission axis of the polarizer is substantially orthogonal to the vibration direction of the reflected light of sunlight incident on the window. The polarizer may be an absorptive polarizer or a reflective polarizer.

Description

窓用ギラツキ防止フィルムAntiglare film for windows
　本発明は窓用ギラツキ防止フィルムに関する。 The present invention relates to an antiglare film for windows.
　建物内または乗り物内から外部の景色を見る際、湖面、海面、建物の窓または壁面、あるいは看板（例えば、金属製の看板、デジタルサイネージ）などからの太陽光の反射光が強いと、ギラツキにより外部景色の美観および視認性が損なわれる場合がある。このような問題に対応するために、建物または乗り物の窓に遮光フィルムを貼り合わせる技術が提案されている（例えば、特許文献１～３）。しかし、遮光フィルムを貼り合わせると、建物または乗り物内部が暗くなりすぎるという問題がある。 When looking at the outside scenery from inside a building or vehicle, if the reflected light of sunlight from a lake surface, sea surface, building window or wall, or a signboard (for example, a metal signboard or digital signage) is strong, The appearance and visibility of the external scenery may be impaired. In order to cope with such a problem, a technique for attaching a light shielding film to a window of a building or a vehicle has been proposed (for example, Patent Documents 1 to 3). However, when a light-shielding film is attached, there is a problem that the inside of the building or vehicle becomes too dark.
特開２０１０－０６５５１４号公報JP 2010-0665514 A 特開２０１２－１０２４９６号公報JP 2012-102496 A 特開平８－０９９５３０号公報JP-A-8-099530
　本発明は上記従来の課題を解決するためになされたものであり、その目的とするところは、入射する太陽光の反射光によるギラツキが抑制され、かつ、内部の明るさを維持し得る窓用ギラツキ防止フィルムを提供することにある。 The present invention has been made to solve the above-described conventional problems, and the object of the present invention is for a window that can suppress glare due to reflected light of incident sunlight and can maintain internal brightness. The object is to provide an antiglare film.
　本発明の実施形態による窓用ギラツキ防止フィルムは、窓に貼り合わせられる窓用ギラツキ防止フィルムである。この窓用ギラツキ防止フィルムは偏光子を含み、該偏光子の透過軸が該窓に入射する太陽光の反射光の振動方向に対して実質的に直交するようにして該窓に貼り合わせられる。
　１つの実施形態においては、上記偏光子は吸収型偏光子である。１つの実施形態においては、上記偏光子の偏光度は９９．０％以上である。
　１つの実施形態においては、上記偏光子は反射型偏光子である。
　１つの実施形態においては、上記窓用ギラツキ防止フィルムは、上記偏光子の上記窓と反対側に配置される、面内位相差Ｒｅ（５５０）が１００ｎｍ～２００ｎｍである位相差層をさらに含み、該位相差層の遅相軸と該偏光子の透過軸とのなす角度が３８°～５２°である。
　１つの実施形態においては、上記窓用ギラツキ防止フィルムは、上記偏光子の上記窓側に配置される、面内位相差Ｒｅ（５５０）が１８０ｎｍ～３２０ｎｍである別の位相差層をさらに含み、該別の位相差層の遅相軸と該偏光子の透過軸とのなす角度が３８°～５２°である。 The antiglare film for windows according to the embodiment of the present invention is an antiglare film for windows that is bonded to a window. This window antiglare film includes a polarizer, and is bonded to the window such that the transmission axis of the polarizer is substantially perpendicular to the vibration direction of reflected sunlight incident on the window.
In one embodiment, the polarizer is an absorptive polarizer. In one embodiment, the polarization degree of the polarizer is 99.0% or more.
In one embodiment, the polarizer is a reflective polarizer.
In one embodiment, the antiglare film for windows further includes a retardation layer having an in-plane retardation Re (550) of 100 nm to 200 nm, which is disposed on the opposite side of the polarizer from the window. The angle formed by the slow axis of the retardation layer and the transmission axis of the polarizer is 38 ° to 52 °.
In one embodiment, the antiglare film for windows further includes another retardation layer having an in-plane retardation Re (550) of 180 nm to 320 nm, which is disposed on the window side of the polarizer. The angle formed between the slow axis of another retardation layer and the transmission axis of the polarizer is 38 ° to 52 °.
　本発明の実施形態によれば、窓に貼り合わせられるフィルムに偏光子を導入し、当該偏光子の透過軸が窓に入射する太陽光の反射光の振動方向に対して実質的に直交するようにして窓に貼り合わせることにより、入射する太陽光の反射光によるギラツキが抑制され、かつ、内部の明るさを維持し得る窓用ギラツキ防止フィルムを実現することができる。 According to an embodiment of the present invention, a polarizer is introduced into a film to be bonded to a window so that the transmission axis of the polarizer is substantially orthogonal to the vibration direction of reflected sunlight incident on the window. By sticking to the window in this way, it is possible to realize a glare-preventing film for windows that can suppress glare due to reflected light of incident sunlight and can maintain the internal brightness.
本発明の１つの実施形態による窓用ギラツキ防止フィルムの概略断面図である。It is a schematic sectional drawing of the antiglare film for windows by one Embodiment of this invention. 本発明の実施形態による窓用ギラツキ防止フィルムに用いられ得る反射型偏光子の一例の概略斜視図である。It is a schematic perspective view of an example of the reflective polarizer which can be used for the glare prevention film for windows by embodiment of this invention.
　以下、本発明の実施形態について説明するが、本発明はこれらの実施形態には限定されない。本明細書において、「実質的に垂直」、「実質的に直交」および「略直交」という表現は、２つの方向のなす角度が９０°±１０°である場合を包含し、好ましくは９０°±７°であり、さらに好ましくは９０°±５°である。「実質的に平行」および「略平行」という表現は、２つの方向のなす角度が０°±１０°である場合を包含し、好ましくは０°±７°であり、さらに好ましくは０°±５°である。さらに、本明細書において単に「垂直」または「直交」あるいは「平行」というときは、実質的に垂直または直交あるいは実質的に平行な状態を含み得るものとする。なお、本明細書において角度に言及するときは、当該角度は基準方向に対して時計回りおよび反時計回りの両方を包含する。 Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments. In the present specification, the expressions “substantially vertical”, “substantially orthogonal” and “substantially orthogonal” include the case where the angle between the two directions is 90 ° ± 10 °, preferably 90 °. ± 7 °, more preferably 90 ° ± 5 °. The expressions “substantially parallel” and “substantially parallel” include the case where the angle between two directions is 0 ° ± 10 °, preferably 0 ° ± 7 °, more preferably 0 ° ± 5 °. Furthermore, in the present specification, the term “vertical”, “orthogonal” or “parallel” may include a substantially vertical, orthogonal or substantially parallel state. In addition, when mentioning an angle in this specification, the said angle includes both clockwise rotation and counterclockwise rotation with respect to a reference direction.
Ａ．窓用ギラツキ防止フィルムの全体構成
　図１は、本発明の１つの実施形態による窓用ギラツキ防止フィルムの概略断面図である。図示例の窓用ギラツキ防止フィルム１００は、偏光子１０を含む。偏光子は、吸収型偏光子であってもよく、反射型偏光子であってもよい。必要に応じて、偏光子の片側または両側に保護フィルム（図示せず）が設けられてもよい。本発明の実施形態においては、窓用ギラツキ防止フィルムが窓に貼り合わされる際に、偏光子の透過軸が当該窓に入射する太陽光の反射光の振動方向に対して実質的に直交するように構成されている。より詳細には以下のとおりである。地面に実質的に平行な方向の面（例えば、湖面や道路）による太陽光の反射光は、その振動方向が地面に実質的に平行な方向（代表的には、水平方向）である。一方、地面に実質的に垂直な方向の面（例えば、建物の壁面や看板）による太陽光の反射光は、その振動方向が地面に実質的に垂直な方向（代表的には、鉛直方向）である。したがって、外部の景色において地面または水平面が支配的である場合には（建物または乗り物の周囲が、例えば湖畔、海岸または平原である場合）、入射する太陽の反射光の振動方向は水平方向が支配的となるので、偏光子の透過軸は、代表的には鉛直方向に実質的に平行な方向に配置され得；外部の景色において地面または水平面に対して垂直な方向の面が支配的である場合には（建物または乗り物の周囲が、例えば建物が林立する市街地である場合）、入射する太陽の反射光の振動方向は鉛直方向が支配的となるので、偏光子の透過軸は、代表的には水平方向に実質的に平行な方向に配置され得る。また、外部の景色において地面または水平面と地面または水平面に対して垂直な方向の面とがそれぞれ一定の割合で含まれている場合には（例えば、湖面または海面と建物とが一定の割合で含まれている場合）、偏光子の透過軸は、代表的には水平方向または鉛直方向に対して当該割合に応じた所定の角度（例えば、４５°）をなすようにして配置され得る。このように、本発明の実施形態による窓用ギラツキ防止フィルムは、太陽光の反射光が内部に入射することを抑制するので、そのような反射光に起因するギラツキを抑制し、結果として、外部景色の美観および視認性を維持し得る。さらに、本発明の実施形態による窓用ギラツキ防止フィルムは、一般的な遮光フィルムと異なり、ギラツキの原因となる太陽光の反射光を選択的に遮断することができるので、内部の明るさを維持し得る。 A. FIG. 1 is a schematic cross-sectional view of a window antiglare film according to one embodiment of the present invention. The window antiglare film 100 in the illustrated example includes a polarizer 10. The polarizer may be an absorptive polarizer or a reflective polarizer. If necessary, a protective film (not shown) may be provided on one side or both sides of the polarizer. In the embodiment of the present invention, when the antiglare film for windows is bonded to the window, the transmission axis of the polarizer is substantially orthogonal to the vibration direction of the reflected sunlight that enters the window. It is configured. More details are as follows. The reflected light of sunlight by a surface (for example, a lake surface or a road) in a direction substantially parallel to the ground is a direction (typically, a horizontal direction) whose vibration direction is substantially parallel to the ground. On the other hand, the reflected light of sunlight from a surface in a direction substantially perpendicular to the ground (for example, a building wall or a signboard) is a direction in which the vibration direction is substantially perpendicular to the ground (typically, the vertical direction). It is. Therefore, when the ground or horizontal plane is dominant in the external scenery (when the surroundings of the building or vehicle are, for example, a lakeside, coast, or plain), the direction of vibration of the reflected sunlight is controlled by the horizontal direction. Thus, the transmission axis of the polarizer can typically be arranged in a direction substantially parallel to the vertical direction; in an external landscape, the plane perpendicular to the ground or horizontal plane is dominant In some cases (when the surroundings of the building or vehicle are, for example, an urban area where the building is forested), the vertical direction is dominant in the oscillation direction of the reflected solar light, so the transmission axis of the polarizer is representative. May be arranged in a direction substantially parallel to the horizontal direction. In addition, when the external landscape includes a certain percentage of the ground or horizontal plane and a plane perpendicular to the ground or horizontal plane (for example, a certain percentage of lake or sea level and buildings are included). The transmission axis of the polarizer can typically be arranged at a predetermined angle (for example, 45 °) corresponding to the ratio with respect to the horizontal or vertical direction. As described above, the antiglare film for windows according to the embodiment of the present invention suppresses the reflected light of sunlight from entering the inside, and thus suppresses the glare caused by such reflected light, and as a result, the external The beauty and visibility of the scenery can be maintained. Furthermore, the antiglare film for windows according to the embodiment of the present invention can selectively block the reflected light of sunlight that causes glare, unlike a general light shielding film, so that the internal brightness is maintained. Can do.
　窓用ギラツキ防止フィルム１００は、図示例のように、偏光子の一方の側に位相差層２０をさらに含んでいてもよい。位相差層２０は、窓用ギラツキ防止フィルムが窓に貼り合わされる際に、代表的には偏光子の窓と反対側（内部側）に配置され得る。位相差層２０は、面内位相差Ｒｅ（５５０）が好ましくは１００ｎｍ～２００ｎｍである。さらに、位相差層２０の遅相軸と偏光子１０の透過軸とのなす角度は、好ましくは３８°～５２°である。このような位相差層を内部側に設けることにより、窓から入射する光を円偏光化することができる。その結果、内部で液晶表示装置（例えば、ノートパソコン、スマートフォン、テレビ）を用いる場合の視認性に対する悪影響を防止することができる。 The window antiglare film 100 may further include a retardation layer 20 on one side of the polarizer as shown in the illustrated example. When the antiglare film for windows is bonded to the window, the retardation layer 20 can be typically disposed on the opposite side (inside) of the polarizer window. The in-plane retardation Re (550) of the retardation layer 20 is preferably 100 nm to 200 nm. Furthermore, the angle formed by the slow axis of the retardation layer 20 and the transmission axis of the polarizer 10 is preferably 38 ° to 52 °. By providing such a retardation layer on the inner side, light incident from the window can be circularly polarized. As a result, it is possible to prevent an adverse effect on visibility when a liquid crystal display device (for example, a notebook computer, a smartphone, or a television) is used inside.
　さらに、窓用ギラツキ防止フィルム１００は、図示例のように、偏光子のもう一方の側に別の位相差層３０をさらに含んでいてもよい。別の位相差層３０は、窓用ギラツキ防止フィルムが窓に貼り合わされる際に、代表的には偏光子の窓側（外部側）に配置され得る。別の位相差層３０は、面内位相差Ｒｅ（５５０）が好ましくは１８０ｎｍ～３２０ｎｍである。さらに、別の位相差層３０の遅相軸と偏光子１０の透過軸とのなす角度は、好ましくは３８°～５２°である。このような別の位相差層を外部側に設けることにより、偏光子１０に入射する太陽光の反射光の振動方向（偏光方向）を代表的には９０°回転させることができる。その結果、窓への貼り合わせの操作性を格段に向上させることができる。より詳細には以下のとおりである。窓用フィルムは通常、ロールから繰り出したフィルムを窓に対して上下方向に貼り合わせるところ、偏光子は製造方法に起因して透過軸がロールの長手方向に対して直交する方向である場合が多いので、このような貼り合わせによれば、偏光子の透過軸は水平方向に実質的に平行な方向となる。したがって、偏光子の透過軸を鉛直方向に実質的に平行な方向となるよう配置したい場合（外部の景色において地面または水平面が支配的である場合）には、フィルムを切り出し、透過軸方向を調整し、窓に貼り合わせなければならない。別の位相差層を設けることにより、貼り合わせ方法を変更することなく（したがって、透過軸を水平方向に維持したまま）入射光の振動方向を変えることによって偏光子での遮断が可能となるので、上記のような煩雑な操作を省略することができる。なお、横延伸の偏光子（長手方向に透過軸を有する偏光子）を用いても、同様の効果が得られ得る。 Further, the antiglare film 100 for windows may further include another retardation layer 30 on the other side of the polarizer as shown in the illustrated example. The other retardation layer 30 can be typically disposed on the window side (external side) of the polarizer when the window antiglare film is bonded to the window. Another retardation layer 30 has an in-plane retardation Re (550) of preferably 180 nm to 320 nm. Furthermore, the angle formed between the slow axis of the other retardation layer 30 and the transmission axis of the polarizer 10 is preferably 38 ° to 52 °. By providing such another retardation layer on the outside, the vibration direction (polarization direction) of the reflected sunlight incident on the polarizer 10 can be typically rotated by 90 °. As a result, the operability of bonding to the window can be significantly improved. More details are as follows. When a film for a window is usually laminated with a film drawn from a roll in a vertical direction with respect to the window, the polarizer is often in a direction in which the transmission axis is orthogonal to the longitudinal direction of the roll due to the production method. Therefore, according to such bonding, the transmission axis of the polarizer is in a direction substantially parallel to the horizontal direction. Therefore, if you want to arrange the transmission axis of the polarizer so that it is substantially parallel to the vertical direction (when the ground or horizontal plane is dominant in the external scenery), cut out the film and adjust the transmission axis direction. And must be attached to the window. By providing another retardation layer, it is possible to block with a polarizer by changing the vibration direction of incident light without changing the bonding method (and thus maintaining the transmission axis in the horizontal direction). The complicated operation as described above can be omitted. The same effect can be obtained even when a horizontally stretched polarizer (a polarizer having a transmission axis in the longitudinal direction) is used.
　位相差層２０および別の位相差層３０は任意の構成要素であり、目的および窓の位置（実質的には、外部の景色）に応じていずれか一方または両方が省略され得る。なお、位相差層２０および別の位相差層３０の両方が存在する場合、それぞれの遅相軸方向は、直交または平行である。 The phase difference layer 20 and the other phase difference layer 30 are optional components, and either one or both of them can be omitted depending on the purpose and the position of the window (substantially the external scenery). In addition, when both the phase difference layer 20 and another phase difference layer 30 exist, each slow axis direction is orthogonal or parallel.
Ｂ．吸収型偏光子
　吸収型偏光子（以下、単に偏光子と称する場合がある）は、代表的には、二色性物質（例えば、ヨウ素）が吸着配向された樹脂フィルムである。例えば、吸収型偏光子を形成する樹脂フィルムは、単層の樹脂フィルムであってもよく、二層以上の積層体であってもよい。 B. Absorptive Polarizer An absorptive polarizer (hereinafter sometimes simply referred to as a polarizer) is typically a resin film in which a dichroic substance (for example, iodine) is adsorbed and oriented. For example, the resin film forming the absorption polarizer may be a single layer resin film or a laminate of two or more layers.
　単層の樹脂フィルムから構成される吸収型偏光子の具体例としては、ポリビニルアルコール（ＰＶＡ）系フィルム、部分ホルマール化ＰＶＡ系フィルム、エチレン・酢酸ビニル共重合体系部分ケン化フィルム等の親水性高分子フィルムに、ヨウ素や二色性染料等の二色性物質による染色処理および延伸処理が施されたもの、ＰＶＡの脱水処理物やポリ塩化ビニルの脱塩酸処理物等ポリエン系配向フィルム等が挙げられる。好ましくは、光学特性に優れることから、ＰＶＡ系フィルムをヨウ素で染色し一軸延伸して得られた偏光子が用いられる。 Specific examples of the absorption polarizer composed of a single-layer resin film include high hydrophilicity such as polyvinyl alcohol (PVA) film, partially formalized PVA film, and ethylene / vinyl acetate copolymer partially saponified film. Examples of molecular films that have been dyed and stretched with dichroic substances such as iodine and dichroic dyes, polyene-based oriented films such as PVA dehydrated products and polyvinyl chloride dehydrochlorinated products It is done. Preferably, a polarizer obtained by dyeing a PVA film with iodine and uniaxially stretching is used because of excellent optical properties.
　上記ヨウ素による染色は、例えば、ＰＶＡ系フィルムをヨウ素水溶液に浸漬することにより行われる。上記一軸延伸の延伸倍率は、好ましくは３～７倍である。延伸は、染色処理後に行ってもよいし、染色しながら行ってもよい。また、延伸してから染色してもよい。必要に応じて、ＰＶＡ系フィルムに、膨潤処理、架橋処理、洗浄処理、乾燥処理等が施される。例えば、染色の前にＰＶＡ系フィルムを水に浸漬して水洗することで、ＰＶＡ系フィルム表面の汚れやブロッキング防止剤を洗浄することができるだけでなく、ＰＶＡ系フィルムを膨潤させて染色ムラなどを防止することができる。 The dyeing with iodine is performed, for example, by immersing a PVA film in an aqueous iodine solution. The stretching ratio of the uniaxial stretching is preferably 3 to 7 times. The stretching may be performed after the dyeing treatment or may be performed while dyeing. Moreover, you may dye | stain after extending | stretching. If necessary, the PVA film is subjected to swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like. For example, by immersing the PVA film in water and washing it before dyeing, not only can the surface of the PVA film be cleaned of dirt and anti-blocking agents, but the PVA film can be swollen to cause uneven staining. Can be prevented.
　積層体を用いて得られる吸収型偏光子の具体例としては、樹脂基材と当該樹脂基材に積層されたＰＶＡ系樹脂層（ＰＶＡ系樹脂フィルム）との積層体、あるいは、樹脂基材と当該樹脂基材に塗布形成されたＰＶＡ系樹脂層との積層体を用いて得られる偏光子が挙げられる。樹脂基材と当該樹脂基材に塗布形成されたＰＶＡ系樹脂層との積層体を用いて得られる偏光子は、例えば、ＰＶＡ系樹脂溶液を樹脂基材に塗布し、乾燥させて樹脂基材上にＰＶＡ系樹脂層を形成して、樹脂基材とＰＶＡ系樹脂層との積層体を得ること；当該積層体を延伸および染色してＰＶＡ系樹脂層を偏光子とすること；により作製され得る。本実施形態においては、延伸は、代表的には積層体をホウ酸水溶液中に浸漬させて延伸することを含む。さらに、延伸は、必要に応じて、ホウ酸水溶液中での延伸の前に積層体を高温（例えば、９５℃以上）で空中延伸することをさらに含み得る。得られた樹脂基材／偏光子の積層体はそのまま用いてもよく（すなわち、樹脂基材を偏光子の保護層としてもよく）、樹脂基材／偏光子の積層体から樹脂基材を剥離し、当該剥離面に目的に応じた任意の適切な保護層を積層して用いてもよい。このような偏光子の製造方法の詳細は、例えば特開２０１２－７３５８０号公報に記載されている。当該公報は、その全体の記載が本明細書に参考として援用される。 As a specific example of the absorption polarizer obtained using the laminate, a laminate of a resin substrate and a PVA resin layer (PVA resin film) laminated on the resin substrate, or a resin substrate and Examples thereof include a polarizer obtained by using a laminate with a PVA-based resin layer formed by coating on the resin base material. For example, a polarizer obtained by using a laminate of a resin base material and a PVA resin layer applied and formed on the resin base material may be obtained by, for example, applying a PVA resin solution to a resin base material and drying it. A PVA-based resin layer is formed thereon to obtain a laminate of a resin base material and a PVA-based resin layer; the laminate is stretched and dyed to make the PVA-based resin layer a polarizer; obtain. In the present embodiment, stretching typically includes immersing the laminate in an aqueous boric acid solution and stretching. Furthermore, the stretching may further include, if necessary, stretching the laminate in the air at a high temperature (for example, 95 ° C. or higher) before stretching in the aqueous boric acid solution. The obtained resin base material / polarizer laminate may be used as it is (that is, the resin base material may be used as a protective layer of the polarizer), and the resin base material is peeled from the resin base material / polarizer laminate. Any appropriate protective layer according to the purpose may be laminated on the release surface. Details of a method for manufacturing such a polarizer are described in, for example, Japanese Patent Application Laid-Open No. 2012-73580. This publication is incorporated herein by reference in its entirety.
　吸収型偏光子は、好ましくは、波長３８０ｎｍ～７８０ｎｍのいずれかの波長で吸収二色性を示す。吸収型偏光子の単体透過率は、好ましくは４０．０％～４６．５％であり、より好ましくは４０．０％～４３．０％であり、さらに好ましくは４０．５％～４２．５％である。吸収型偏光子の偏光度は、好ましくは９９．０％以上であり、より好ましくは９９．５％以上であり、さらに好ましくは９９．９％以上である。なお、単体透過率は、ＪＩＳ Ｚ ８７０１－１９８２の２度視野（Ｃ光源）により、視感度補正を行ったＹ値である。 The absorptive polarizer preferably exhibits absorption dichroism at any wavelength between 380 nm and 780 nm. The single transmittance of the absorptive polarizer is preferably 40.0% to 46.5%, more preferably 40.0% to 43.0%, and further preferably 40.5% to 42.5%. %. The degree of polarization of the absorbing polarizer is preferably 99.0% or more, more preferably 99.5% or more, and further preferably 99.9% or more. The single transmittance is a Y value obtained by correcting the visibility with a two-degree field of view (C light source) of JIS Z 8701-1982.
　吸収型偏光子の厚みは、例えば１μｍ～８０μｍであり得る。 The thickness of the absorbing polarizer can be, for example, 1 μm to 80 μm.
Ｃ．反射型偏光子
　反射型偏光子は、特定の偏光状態（偏光方向）の偏光を透過し、それ以外の偏光状態の光を反射する機能を有する。反射型偏光子は、直線偏光分離型であってもよく、円偏光分離型であってもよい。以下、一例として、直線偏光分離型の反射型偏光子について簡単に説明する。なお、円偏光分離型の反射型偏光子としては、例えば、コレステリック液晶を固定化したフィルムとλ／４板との積層体が挙げられる。 C. Reflective Polarizer The reflective polarizer has a function of transmitting polarized light in a specific polarization state (polarization direction) and reflecting light in other polarization states. The reflective polarizer may be a linearly polarized light separation type or a circularly polarized light separation type. Hereinafter, as an example, a linearly polarized light separation type reflective polarizer will be briefly described. Examples of the circularly polarized light separation type reflective polarizer include a laminate of a film in which cholesteric liquid crystal is fixed and a λ / 4 plate.
　図２は、反射型偏光子の一例の概略斜視図である。反射型偏光子は、複屈折性を有する層Ａと複屈折性を実質的に有さない層Ｂとが交互に積層された多層積層体である。例えば、このような多層積層体の層の総数は、５０～１０００であり得る。図示例では、Ａ層のｘ軸方向の屈折率ｎｘがｙ軸方向の屈折率ｎｙより大きく、Ｂ層のｘ軸方向の屈折率ｎｘとｙ軸方向の屈折率ｎｙとは実質的に同一である。したがって、Ａ層とＢ層との屈折率差は、ｘ軸方向において大きく、ｙ軸方向においては実質的にゼロである。その結果、ｘ軸方向が反射軸となり、ｙ軸方向が透過軸となる。Ａ層とＢ層とのｘ軸方向における屈折率差は、好ましくは０．２～０．３である。なお、ｘ軸方向は、反射型偏光子の製造方法における反射型偏光子の延伸方向に対応する。また、反射型偏光子は、図示例のように、最外層として反射層Ｒを含んでいてもよい。 FIG. 2 is a schematic perspective view of an example of a reflective polarizer. The reflective polarizer is a multilayer laminate in which layers A having birefringence and layers B having substantially no birefringence are alternately laminated. For example, the total number of layers in such a multilayer stack can be 50-1000. In the illustrated example, the refractive index nx in the x-axis direction of the A layer is larger than the refractive index ny in the y-axis direction, and the refractive index nx in the x-axis direction and the refractive index ny in the y-axis direction of the B layer are substantially the same. is there. Accordingly, the difference in refractive index between the A layer and the B layer is large in the x-axis direction and is substantially zero in the y-axis direction. As a result, the x-axis direction becomes the reflection axis, and the y-axis direction becomes the transmission axis. The refractive index difference in the x-axis direction between the A layer and the B layer is preferably 0.2 to 0.3. The x-axis direction corresponds to the extending direction of the reflective polarizer in the reflective polarizer manufacturing method. Further, the reflective polarizer may include a reflective layer R as the outermost layer as shown in the example of the drawing.
　上記Ａ層は、好ましくは、延伸により複屈折性を発現する材料で構成される。このような材料の代表例としては、ナフタレンジカルボン酸ポリエステル（例えば、ポリエチレンナフタレート）、ポリカーボネートおよびアクリル系樹脂（例えば、ポリメチルメタクリレート）が挙げられる。ポリエチレンナフタレートが好ましい。上記Ｂ層は、好ましくは、延伸しても複屈折性を実質的に発現しない材料で構成される。このような材料の代表例としては、ナフタレンジカルボン酸とテレフタル酸とのコポリエステルが挙げられる。 The A layer is preferably made of a material that develops birefringence by stretching. Representative examples of such materials include naphthalene dicarboxylic acid polyesters (for example, polyethylene naphthalate), polycarbonates, and acrylic resins (for example, polymethyl methacrylate). Polyethylene naphthalate is preferred. The B layer is preferably made of a material that does not substantially exhibit birefringence even when stretched. A typical example of such a material is a copolyester of naphthalenedicarboxylic acid and terephthalic acid.
　反射型偏光子としては、例えば、特表平９－５０７３０８号公報に記載のものが使用され得る。また、反射型偏光子は、市販品をそのまま用いてもよく、市販品を２次加工（例えば、延伸）して用いてもよい。市販品としては、例えば、３Ｍ社製の商品名ＤＢＥＦ、３Ｍ社製の商品名ＡＰＦが挙げられる。 As the reflective polarizer, for example, the one described in JP-T-9-507308 can be used. As the reflective polarizer, a commercially available product may be used as it is, or a commercially available product may be used after secondary processing (for example, stretching). As a commercial item, 3M company brand name DBEF and 3M company brand name APF are mentioned, for example.
Ｄ．保護フィルム
　保護フィルムは、代表的には、偏光子が吸収型偏光子である場合に用いられ得る。保護フィルムとしては、偏光子の保護フィルムとして使用できる任意の適切な樹脂フィルムが採用され得る。当該フィルムの主成分となる材料の具体例としては、トリアセチルセルロース（ＴＡＣ）等のセルロース系樹脂や、ポリエステル系、ポリビニルアルコール系、ポリカーボネート系、ポリアミド系、ポリイミド系、ポリエーテルスルホン系、ポリスルホン系、ポリスチレン系、ポリノルボルネン系、ポリオレフィン系、（メタ）アクリル系、アセテート系等の透明樹脂等が挙げられる。また、（メタ）アクリル系、ウレタン系、（メタ）アクリルウレタン系、エポキシ系、シリコーン系等の熱硬化型樹脂または紫外線硬化型樹脂等も挙げられる。この他にも、例えば、シロキサン系ポリマー等のガラス質系ポリマーも挙げられる。また、特開２００１－３４３５２９号公報（ＷＯ０１／３７００７）に記載のポリマーフィルムも使用できる。このフィルムの材料としては、例えば、側鎖に置換または非置換のイミド基を有する熱可塑性樹脂と、側鎖に置換または非置換のフェニル基ならびにニトリル基を有する熱可塑性樹脂を含有する樹脂組成物が使用でき、例えば、イソブテンとＮ－メチルマレイミドからなる交互共重合体と、アクリロニトリル・スチレン共重合体とを有する樹脂組成物が挙げられる。当該ポリマーフィルムは、例えば、上記樹脂組成物の押出成形物であり得る。 D. Protective film The protective film can be typically used when the polarizer is an absorptive polarizer. As the protective film, any appropriate resin film that can be used as a protective film for a polarizer can be adopted. Specific examples of the material as the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyester-based, polyvinyl alcohol-based, polycarbonate-based, polyamide-based, polyimide-based, polyethersulfone-based, and polysulfone-based materials. And transparent resins such as polystyrene, polynorbornene, polyolefin, (meth) acryl, and acetate. Further, thermosetting resins such as (meth) acrylic, urethane-based, (meth) acrylurethane-based, epoxy-based, and silicone-based or ultraviolet curable resins are also included. In addition to this, for example, a glassy polymer such as a siloxane polymer is also included. Further, a polymer film described in JP-A-2001-343529 (WO01 / 37007) can also be used. As a material for this film, for example, a resin composition containing a thermoplastic resin having a substituted or unsubstituted imide group in the side chain and a thermoplastic resin having a substituted or unsubstituted phenyl group and nitrile group in the side chain For example, a resin composition having an alternating copolymer of isobutene and N-methylmaleimide and an acrylonitrile / styrene copolymer can be mentioned. The polymer film can be, for example, an extruded product of the resin composition.
　窓用ギラツキ防止フィルムにおいて視認側（窓と反対側、内部側）に保護フィルムが配置される場合、視認側保護フィルムには、必要に応じて、ハードコート処理、反射防止処理、スティッキング防止処理、アンチグレア処理等の表面処理が施されていてもよい。 When a protective film is disposed on the viewing side (opposite side of the window, inside) in the antiglare film for windows, the hard coating treatment, antireflection treatment, antisticking treatment, Surface treatment such as anti-glare treatment may be applied.
　窓用ギラツキ防止フィルムにおいて視認側と反対側（窓側、外部側）に保護フィルムが配置される場合、当該保護フィルムは、光学的に等方性であることが好ましい。本明細書において「光学的に等方性である」とは、面内位相差Ｒｅ（５５０）が０ｎｍ～１０ｎｍであり、厚み方向の位相差Ｒｔｈ（５５０）が－１０ｎｍ～＋１０ｎｍであることをいう。本明細書において「Ｒｅ（λ）」は、２３℃における波長λｎｍの光で測定した面内位相差である。例えば、「Ｒｅ（５５０）」は、２３℃における波長５５０ｎｍの光で測定した面内位相差である。Ｒｅ（λ）は、層（フィルム）の厚みをｄ（ｎｍ）としたとき、式：Ｒｅ（λ）＝（ｎｘ－ｎｙ）×ｄによって求められる。「Ｒｔｈ（λ）」は、２３℃における波長λｎｍの光で測定した厚み方向の位相差である。例えば、「Ｒｔｈ（５５０）」は、２３℃における波長５５０ｎｍの光で測定した厚み方向の位相差である。Ｒｔｈ（λ）は、層（フィルム）の厚みをｄ（ｎｍ）としたとき、式：Ｒｔｈ（λ）＝（ｎｘ－ｎｚ）×ｄによって求められる。「ｎｘ」は面内の屈折率が最大になる方向（すなわち、遅相軸方向）の屈折率であり、「ｎｙ」は面内で遅相軸と直交する方向（すなわち、進相軸方向）の屈折率であり、「ｎｚ」は厚み方向の屈折率である。 When a protective film is disposed on the side opposite to the viewing side (window side, external side) in the antiglare film for windows, the protective film is preferably optically isotropic. In this specification, “optically isotropic” means that the in-plane retardation Re (550) is 0 nm to 10 nm and the thickness direction retardation Rth (550) is −10 nm to +10 nm. Say. In this specification, “Re (λ)” is an in-plane retardation measured with light having a wavelength of λ nm at 23 ° C. For example, “Re (550)” is an in-plane retardation measured with light having a wavelength of 550 nm at 23 ° C. Re (λ) is determined by the formula: Re (λ) = (nx−ny) × d, where d (nm) is the thickness of the layer (film). “Rth (λ)” is a retardation in the thickness direction measured with light having a wavelength of λ nm at 23 ° C. For example, “Rth (550)” is a retardation in the thickness direction measured with light having a wavelength of 550 nm at 23 ° C. Rth (λ) is determined by the formula: Rth (λ) = (nx−nz) × d, where d (nm) is the thickness of the layer (film). “Nx” is the refractive index in the direction in which the in-plane refractive index is maximum (ie, the slow axis direction), and “ny” is the direction orthogonal to the slow axis in the plane (ie, the fast axis direction). “Nz” is the refractive index in the thickness direction.
Ｅ．位相差層
　位相差層２０は、面内位相差Ｒｅ（５５０）が上記のとおり好ましくは１００ｎｍ～２００ｎｍであり、より好ましくは１２０ｎｍ～１８０ｎｍ、さらに好ましくは１３０ｎｍ～１６０ｎｍである。 E. Retardation Layer The retardation layer 20 has an in-plane retardation Re (550) of preferably 100 nm to 200 nm, more preferably 120 nm to 180 nm, and still more preferably 130 nm to 160 nm as described above.
　位相差層は、好ましくは、ｎｘ＞ｎｙ≧ｎｚの屈折率特性を示す。したがって、位相差層は遅相軸を有する。偏光子１０の透過軸と位相差層２０の遅相軸とのなす角度は、好ましくは３８°～５２°であり、より好ましくは４２°～４８°であり、さらに好ましくは約４５°である。なお、本明細書において「ｎｙ＝ｎｚ」はｎｙとｎｚが完全に等しい場合だけではなく、実質的に等しい場合を包含する。したがって、本発明の効果を損なわない範囲で、ｎｙ＜ｎｚとなる場合があり得る。 The retardation layer preferably exhibits a refractive index characteristic of nx> ny ≧ nz. Therefore, the retardation layer has a slow axis. The angle formed by the transmission axis of the polarizer 10 and the slow axis of the retardation layer 20 is preferably 38 ° to 52 °, more preferably 42 ° to 48 °, and even more preferably about 45 °. . In the present specification, “ny = nz” includes not only the case where ny and nz are completely equal, but also the case where they are substantially equal. Therefore, ny <nz may be satisfied as long as the effects of the present invention are not impaired.
　位相差層のＮｚ係数は、好ましくは０．９～２．５であり、より好ましくは０．９～１．５であり、さらに好ましくは０．９～１．３である。Ｎｚ係数は、Ｎｚ＝Ｒｔｈ／Ｒｅによって求められる。 The Nz coefficient of the retardation layer is preferably 0.9 to 2.5, more preferably 0.9 to 1.5, and still more preferably 0.9 to 1.3. The Nz coefficient is obtained by Nz = Rth / Re.
　位相差層は、位相差値が測定光の波長に応じて大きくなる逆分散波長特性を示してもよく、位相差値が測定光の波長に応じて小さくなる正の波長分散特性を示してもよく、位相差値が測定光の波長によってもほとんど変化しないフラットな波長分散特性を示してもよい。位相差層が逆分散波長特性を示す場合、Ｒｅ（４５０）／Ｒｅ（５５０）は、好ましくは０．８５以上１．００未満であり、より好ましくは０．９５以上１．００未満であり；Ｒｅ（５５０）／Ｒｅ（６５０）は、好ましくは０．９０以上１．００未満であり、より好ましくは０．９５以上１．００未満である。位相差層が正の分散波長特性またはフラットな波長分散特性を示す場合、Ｒｅ（４５０）／Ｒｅ（５５０）は、好ましくは１．００～１．１５であり、より好ましくは１．００～１．０７であり；Ｒｅ（５５０）／Ｒｅ（６５０）は、好ましくは１．００～１．１０であり、より好ましくは１．００～１．０５である。 The retardation layer may exhibit reverse dispersion wavelength characteristics in which the retardation value increases with the wavelength of the measurement light, or may exhibit positive wavelength dispersion characteristics in which the retardation value decreases with the wavelength of the measurement light. The phase difference value may exhibit a flat chromatic dispersion characteristic that hardly changes depending on the wavelength of the measurement light. When the retardation layer exhibits reverse dispersion wavelength characteristics, Re (450) / Re (550) is preferably 0.85 or more and less than 1.00, more preferably 0.95 or more and less than 1.00; Re (550) / Re (650) is preferably 0.90 or more and less than 1.00, and more preferably 0.95 or more and less than 1.00. When the retardation layer exhibits positive dispersion wavelength characteristics or flat wavelength dispersion characteristics, Re (450) / Re (550) is preferably 1.00 to 1.15, more preferably 1.00 to 1. Re (550) / Re (650) is preferably 1.00 to 1.10, more preferably 1.00 to 1.05.
　位相差層の厚みは、上記所望の面内位相差が得られるように設定され得る。位相差層の厚みは、好ましくは２０μｍ～１００μｍであり、より好ましくは３０μｍ～７０μｍである。 The thickness of the retardation layer can be set so as to obtain the desired in-plane retardation. The thickness of the retardation layer is preferably 20 μm to 100 μm, more preferably 30 μm to 70 μm.
　位相差層は、上記特性を実現し得る任意の適切な樹脂フィルムで構成され得る。位相差層を形成する樹脂としては、例えば、ポリアリレート、ポリアミド、ポリイミド、ポリエステル、ポリアリールエーテルケトン、ポリアミドイミド、ポリエステルイミド、ポリビニルアルコール、ポリフマル酸エステル、ポリエーテルサルフォン、ポリサルフォン、ノルボルネン樹脂、ポリカーボネート樹脂、セルロース樹脂およびポリウレタンが挙げられる。これらの樹脂は、単独で用いてもよく組み合わせて用いてもよい。位相差層は、これらの樹脂から形成されたフィルムを、樹脂の種類および上記所望の特性に応じた条件で延伸することにより得られ得る。 The retardation layer may be composed of any appropriate resin film that can realize the above characteristics. Examples of the resin forming the retardation layer include polyarylate, polyamide, polyimide, polyester, polyaryletherketone, polyamideimide, polyesterimide, polyvinyl alcohol, polyfumaric acid ester, polyethersulfone, polysulfone, norbornene resin, and polycarbonate. Resins, cellulose resins and polyurethanes can be mentioned. These resins may be used alone or in combination. The retardation layer can be obtained by stretching a film formed from these resins under conditions according to the type of resin and the desired characteristics.
Ｆ．別の位相差層
　別の位相差層３０は、面内位相差Ｒｅ（５５０）が上記のとおり好ましくは１８０ｎｍ～３２０ｎｍであり、より好ましくは２００ｎｍ～２９０ｎｍであり、さらに好ましくは２３０ｎｍ～２８０ｎｍである。 F. Another Retardation Layer Another retardation layer 30 has an in-plane retardation Re (550) of preferably 180 nm to 320 nm, more preferably 200 nm to 290 nm, and further preferably 230 nm to 280 nm as described above. .
　別の位相差層の厚みは、上記所望の面内位相差が得られるように設定され得る。別の位相差層の厚みは、好ましくは２０μｍ～１５０μｍであり、より好ましくは４０μｍ～１００μｍである。 The thickness of the other retardation layer can be set so as to obtain the desired in-plane retardation. The thickness of the other retardation layer is preferably 20 μm to 150 μm, more preferably 40 μm to 100 μm.
　別の位相差層の上記以外の特性、構成材料、軸角度等は、位相差層に関して上記Ｅ項で説明したとおりである。 Other characteristics, constituent materials, shaft angles, etc. of the other retardation layer are as described in the above section E for the retardation layer.
　以下、実施例によって本発明を具体的に説明するが、本発明はこれら実施例によって限定されるものではない。実施例における評価方法は下記の通りである。また、特に明記しない限り、実施例における「部」および「％」は重量基準である。 Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. Evaluation methods in the examples are as follows. Unless otherwise specified, “parts” and “%” in the examples are based on weight.
（１）単体透過率および偏光度
　実施例および比較例のフィルムについて、分光光度計［村上色彩技術研究所（株）製、製品名「ＤＯＴ－３」］を用いて測定した。偏光度は、偏光板の平行透過率（Ｈ０）および直交透過率（Ｈ９０）を測定し、式：偏光度（％）＝｛（Ｈ０－Ｈ９０）／（Ｈ０＋Ｈ９０）｝(１／２)×１００より求めた。平行透過率（Ｈ０）は、同じ偏光板２枚を互いの吸収軸が平行となるように重ね合わせて作製した平行型積層偏光板の透過率の値である。また、直交透過率（Ｈ９０）は、同じ偏光板２枚を互いの吸収軸が直交するように重ね合わせて作製した直交型積層偏光板の透過率の値である。これらの透過率は、ＪＩＳ Ｚ ８７０１－１９８２の２度視野（Ｃ光源）により、視感度補正を行ったＹ値である。なお、比較例で用いた遮光フィルムは偏光子を含ず光学的異方性を有さないので、単純にフィルムを２枚重ねて測定した。
（２）屋内輝度
　ＬＥＤベースライト（大光電機社製「ＬＺＤ－９２２８８ＮＷ」）を用いて、水を張ったアルミバットに入射角６０°で光照射を行った。当該照射光の正反射光が射す位置に輝度計（コニカミノルタ社製「ＬＳ－１５０」：測定角１°、測定エリアφ１４．４ｍｍ）を設置した。輝度計とアルミバットとの間に実施例および比較例で作製したフィルム付ガラス板を窓ガラス代替品として設置し、ガラス越しに水面からの反射輝度を測定した。
（３）屋外輝度
　晴天時の屋外の日向の所定の位置かつ所定の方向に輝度計（コニカミノルタ社製「ＬＳ－１５０」：測定角１°、測定エリアφ１４．４ｍｍ）を設置し、所定の建物の瓦屋根の輝度を測定できるようにした。輝度計と当該建物との間に実施例および比較例で作製したフィルム付ガラス板を窓ガラス代替品として設置し、ガラス越しに瓦屋根の輝度を測定した。
（４）景観
　上記（３）の輝度計を設置した位置から上記（３）と同様のガラス越しに景観を目視により観察し、ギラツキおよび明るさを評価した。 (1) Single transmittance and degree of polarization The films of Examples and Comparative Examples were measured using a spectrophotometer [manufactured by Murakami Color Research Laboratory Co., Ltd., product name “DOT-3”]. The degree of polarization is obtained by measuring the parallel transmittance (H 0 ) and orthogonal transmittance (H 90 ) of the polarizing plate, and the formula: degree of polarization (%) = {(H 0 −H 90 ) / (H 0 + H 90 )} Obtained from (1/2) × 100. The parallel transmittance (H 0 ) is a transmittance value of a parallel laminated polarizing plate produced by superposing two identical polarizing plates so that their absorption axes are parallel to each other. The orthogonal transmittance (H 90 ) is a value of the transmittance of an orthogonal laminated polarizing plate produced by superposing two identical polarizing plates so that their absorption axes are orthogonal to each other. These transmittances are Y values obtained by correcting the visibility with a two-degree field of view (C light source) of JIS Z 8701-1982. In addition, since the light shielding film used by the comparative example does not have a polarizer and does not have optical anisotropy, it measured by having piled up two films | membranes simply.
(2) Indoor Luminance Using an LED base light (“LZD-92288NW” manufactured by Daiko Electric Co., Ltd.), the aluminum bat filled with water was irradiated with light at an incident angle of 60 °. A luminance meter (“LS-150” manufactured by Konica Minolta, Inc .: measurement angle 1 °, measurement area φ14.4 mm) was installed at a position where the regular reflection light of the irradiation light was emitted. A glass plate with a film prepared in Examples and Comparative Examples was installed between a luminance meter and an aluminum bat as a substitute for window glass, and the reflected luminance from the water surface was measured through the glass.
(3) Outdoor brightness A brightness meter ("LS-150" manufactured by Konica Minolta Co., Ltd .: measurement angle 1 °, measurement area φ14.4 mm) is installed in a predetermined position and in a predetermined direction in the sunny day. The brightness of the tiled roof of the building can be measured. The glass plate with a film produced in the examples and comparative examples was installed between the luminance meter and the building as a substitute for window glass, and the luminance of the tile roof was measured through the glass.
(4) Landscape The scenery was visually observed through the same glass as in (3) above from the position where the luminance meter of (3) was installed, and glare and brightness were evaluated.
＜実施例１＞
　ポリビニルアルコールを主成分とする高分子フィルム［クラレ製、商品名「９Ｐ７５Ｒ（厚み：７５μｍ、平均重合度：２，４００、ケン化度９９．９モル％）」］を水浴中に１分間浸漬させつつ搬送方向に１．２倍に延伸した後、ヨウ素濃度０．３重量％の水溶液中で１分間浸漬することで、染色しながら、搬送方向に、全く延伸していないフィルム（原長）を基準として３倍に延伸し、ホウ酸濃度４重量％、ヨウ化カリウム濃度５重量％の水溶液中に浸漬しながら、搬送方向に、原長基準で６倍に延伸し、７０℃で２分間乾燥することにより、偏光子（厚み２８μｍ）を作製した。偏光子の単体透過率および偏光度を表１に示す。得られた偏光子の両側に保護フィルム（ＴＡＣフィルム、厚み４０μｍ）を貼り合わせて偏光板を得た。得られた偏光板を、粘着剤層（厚み２３μｍ）を介してガラス板に貼り合わせ、偏光板付ガラス板を作製した。このとき、偏光子の透過軸が鉛直方向と実質的に平行となるように（反射光の振動方向に対して実質的に直交するように）貼り合わせた。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 1>
A polymer film composed mainly of polyvinyl alcohol (manufactured by Kuraray, trade name “9P75R (thickness: 75 μm, average polymerization degree: 2,400, saponification degree 99.9 mol%)”) is immersed in a water bath for 1 minute. While stretching 1.2 times in the transport direction, it is immersed in an aqueous solution having an iodine concentration of 0.3% by weight for 1 minute to dye a film (original length) that is not stretched in the transport direction while being dyed. Stretched 3 times as a standard, dipped in an aqueous solution of boric acid concentration 4% by weight and potassium iodide concentration 5% by weight, stretched 6 times on the basis of the original length in the transport direction, and dried at 70 ° C. for 2 minutes Thus, a polarizer (thickness 28 μm) was produced. Table 1 shows the single transmittance and the degree of polarization of the polarizer. A protective film (TAC film, thickness 40 μm) was bonded to both sides of the obtained polarizer to obtain a polarizing plate. The obtained polarizing plate was bonded to a glass plate via an adhesive layer (thickness: 23 μm) to produce a polarizing plate-attached glass plate. At this time, bonding was performed such that the transmission axis of the polarizer was substantially parallel to the vertical direction (substantially perpendicular to the vibration direction of the reflected light). The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜実施例２＞
　偏光子の製造条件を変更して単体透過率および偏光度を表１のようにしたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 2>
A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the production conditions of the polarizer were changed and the single transmittance and the degree of polarization were as shown in Table 1. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜実施例３＞
　偏光子の製造条件を変更して単体透過率および偏光度を表１のようにしたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 3>
A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the production conditions of the polarizer were changed and the single transmittance and the degree of polarization were as shown in Table 1. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜実施例４＞
　偏光板の代わりに反射型偏光子（３Ｍ社製「ＡＰＦ」）を用いたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 4>
A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that a reflective polarizer (“APF” manufactured by 3M) was used instead of the polarizing plate. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜実施例５＞
　実施例１の偏光板のガラス板と反対側に配置される保護フィルム表面に位相差フィルム（いわゆるλ／４板）を貼り合わせたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。なお、位相差フィルムは、ポリアリレート系樹脂フィルムの延伸フィルムであり、その面内位相差Ｒｅ（５５０）は１４７ｎｍであった。さらに、位相差フィルムは、その遅相軸と偏光子の吸収軸とのなす角度が４５°となるようにして貼り合わせた。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 5>
A glass plate with a polarizing plate was obtained in the same manner as in Example 1 except that a retardation film (so-called λ / 4 plate) was bonded to the surface of the protective film disposed on the side opposite to the glass plate of the polarizing plate of Example 1. Produced. The retardation film was a stretched film of a polyarylate resin film, and the in-plane retardation Re (550) thereof was 147 nm. Furthermore, the retardation film was bonded so that the angle formed between the slow axis and the absorption axis of the polarizer was 45 °. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜実施例６＞
　実施例１の偏光板のガラス板側に配置される保護フィルム表面に位相差フィルム（いわゆるλ／２板）を貼り合わせたこと、および、偏光子の透過軸が水平方向と実質的に平行となるように（反射光の振動方向に対して実質的に平行となるように）偏光板とガラス板とを貼り合わせたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。なお、位相差フィルムは、ポリカーボネート系樹脂フィルムの延伸フィルムであり、その面内位相差Ｒｅ（５５０）は２７０ｎｍであった。さらに、位相差フィルムは、その遅相軸と偏光子の吸収軸とのなす角度が４５°となるようにして貼り合わせた。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 6>
The retardation film (so-called λ / 2 plate) was bonded to the surface of the protective film disposed on the glass plate side of the polarizing plate of Example 1, and the transmission axis of the polarizer was substantially parallel to the horizontal direction. A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the polarizing plate and the glass plate were bonded together (so as to be substantially parallel to the vibration direction of the reflected light). The retardation film was a stretched film of a polycarbonate resin film, and the in-plane retardation Re (550) was 270 nm. Furthermore, the retardation film was bonded so that the angle formed between the slow axis and the absorption axis of the polarizer was 45 °. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜実施例７＞
　実施例１の偏光板のガラス板と反対側に配置される保護フィルム表面に実施例５の位相差フィルム（λ／４板）を貼り合わせたこと、ガラス板側に配置される保護フィルム表面に実施例６の位相差フィルム（λ／２板）を貼り合わせたこと、および、偏光子の透過軸が水平方向と実質的に平行となるように（反射光の振動方向に対して実質的に平行となるように）偏光板とガラス板とを貼り合わせたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。なお、λ／４板およびλ／２板は、それぞれの遅相軸と偏光子の吸収軸とのなす角度が４５°となるようにして貼り合わせた。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Example 7>
On the surface of the protective film disposed on the glass plate side, the retardation film (λ / 4 plate) of Example 5 was bonded to the surface of the protective film disposed on the side opposite to the glass plate of the polarizing plate of Example 1. The retardation film (λ / 2 plate) of Example 6 was bonded, and the transmission axis of the polarizer was substantially parallel to the horizontal direction (substantially with respect to the vibration direction of the reflected light). A glass plate with a polarizing plate was produced in the same manner as in Example 1 except that the polarizing plate and the glass plate were bonded together (in parallel). The λ / 4 plate and the λ / 2 plate were bonded together so that the angle formed between the slow axis and the absorption axis of the polarizer was 45 °. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜比較例１＞
　偏光板を貼り付けないガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Comparative Example 1>
A glass plate without a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜比較例２＞
　偏光板の代わりに市販の遮光フィルム（トラスコ中山社製「ＴＳＦ４５１８ＳＭＫ」）を用いたこと以外は実施例１と同様にして、遮光フィルム付ガラス板を作製した。なお、当該遮光フィルムに光学的な異方性はないが、フィルム短辺が水平方向（反射光の振動方向に対して実質的に平行）となるようにして貼り合わせた。得られた遮光フィルム付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Comparative Example 2>
A glass plate with a light-shielding film was produced in the same manner as in Example 1 except that a commercially available light-shielding film (“TSF4518SMK” manufactured by Trusco Nakayama Co., Ltd.) was used instead of the polarizing plate. In addition, although the said light shielding film did not have optical anisotropy, it bonded together so that a film short side might become a horizontal direction (substantially parallel to the vibration direction of reflected light). The obtained glass plate with a light-shielding film was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜比較例３＞
　フィルム長辺が水平方向（反射光の振動方向に対して実質的に平行）となるようにして貼り合わせたこと以外は比較例２と同様にして遮光フィルム付ガラス板を作製した。得られた遮光フィルム付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Comparative Example 3>
A glass plate with a light-shielding film was produced in the same manner as in Comparative Example 2, except that the film was bonded so that the long side of the film was in the horizontal direction (substantially parallel to the vibration direction of the reflected light). The obtained glass plate with a light-shielding film was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜比較例４＞
　偏光板の代わりに市販の遮光フィルム（トラスコ中山社製「ＴＳＦ４５１８ＴＭ」）を用いたこと以外は実施例１と同様にして、遮光フィルム付ガラス板を作製した。なお、当該遮光フィルムに光学的な異方性はないが、フィルム短辺が水平方向（反射光の振動方向に対して実質的に平行）となるようにして貼り合わせた。得られた遮光フィルム付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Comparative example 4>
A glass plate with a light-shielding film was produced in the same manner as in Example 1 except that a commercially available light-shielding film (“TSF4518TM” manufactured by Trusco Nakayama Co., Ltd.) was used instead of the polarizing plate. In addition, although the said light shielding film did not have optical anisotropy, it bonded together so that a film short side might become a horizontal direction (substantially parallel to the vibration direction of reflected light). The obtained glass plate with a light-shielding film was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜比較例５＞
　フィルム長辺が水平方向（反射光の振動方向に対して実質的に平行）となるようにして貼り合わせたこと以外は比較例４と同様にして遮光フィルム付ガラス板を作製した。得られた遮光フィルム付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Comparative Example 5>
A glass plate with a light-shielding film was produced in the same manner as in Comparative Example 4 except that the film was bonded so that the long side of the film was in the horizontal direction (substantially parallel to the vibration direction of the reflected light). The obtained glass plate with a light-shielding film was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
＜比較例６＞
　偏光子の透過軸が水平方向と実質的に平行となるように（反射光の振動方向に対して実質的に平行となるように）偏光板をガラス板に貼り合わせたこと以外は実施例１と同様にして、偏光板付ガラス板を作製した。得られた偏光板付ガラス板を上記（２）～（４）の評価に供した。結果を表１に示す。 <Comparative Example 6>
Example 1 except that the polarizing plate is bonded to the glass plate so that the transmission axis of the polarizer is substantially parallel to the horizontal direction (so that it is substantially parallel to the vibration direction of the reflected light). In the same manner, a glass plate with a polarizing plate was produced. The obtained glass plate with a polarizing plate was subjected to the evaluations (2) to (4) above. The results are shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　表１から明らかなように、本発明の実施例の窓用ギラツキ防止フィルムは、内部の明るさを維持しつつ、入射する太陽光の反射光によるギラツキが抑制することができる。さらに、実施例１および２と実施例３および４とを比較すると明らかなように、偏光子の単体透過率を低くする（偏光度を高くする）ことにより、効果が顕著となることがわかる。 As can be seen from Table 1, the glare-preventing film for windows according to the examples of the present invention can suppress glare caused by incident sunlight reflected light while maintaining internal brightness. Further, as is clear when Examples 1 and 2 are compared with Examples 3 and 4, it can be seen that the effect becomes remarkable by reducing the single transmittance of the polarizer (increasing the degree of polarization).
　本発明の実施形態による窓用ギラツキ防止フィルムは、建物および乗り物等の窓に好適に利用され得る。 The antiglare film for windows according to the embodiment of the present invention can be suitably used for windows of buildings and vehicles.
　１０　　　偏光子
　２０　　　位相差層
　３０　　　別の位相差層
１００　　　窓用ギラツキ防止フィルム
 
  DESCRIPTION OF SYMBOLS 10 Polarizer 20 Phase difference layer 30 Another phase difference layer 100 Glare prevention film for windows

Claims (6)

  1. 　窓に貼り合わせられる窓用ギラツキ防止フィルムであって、
    　偏光子を含み、
    　該偏光子の透過軸が該窓に入射する太陽光の反射光の振動方向に対して実質的に直交するようにして該窓に貼り合わせられる、
    　窓用ギラツキ防止フィルム。     An antiglare film for windows that is bonded to a window,
    Including a polarizer,
    The polarizer is bonded to the window so that the transmission axis is substantially orthogonal to the vibration direction of the reflected sunlight incident on the window.
    Antiglare film for windows.
  2. 　前記偏光子が吸収型偏光子である、請求項１に記載の窓用ギラツキ防止フィルム。 The antiglare film for windows according to claim 1, wherein the polarizer is an absorptive polarizer.
  3. 　前記偏光子の偏光度が９９．０％以上である、請求項２に記載の窓用ギラツキ防止フィルム。 The antiglare film for windows according to claim 2, wherein the polarizer has a polarization degree of 99.0% or more.
  4. 　前記偏光子が反射型偏光子である、請求項１に記載の窓用ギラツキ防止フィルム。 The antiglare film for windows according to claim 1, wherein the polarizer is a reflective polarizer.
  5. 　前記偏光子の前記窓と反対側に配置される、面内位相差Ｒｅ（５５０）が１００ｎｍ～２００ｎｍである位相差層をさらに含み、該位相差層の遅相軸と該偏光子の透過軸とのなす角度が３８°～５２°である、請求項１から４のいずれかに記載の窓用ギラツキ防止フィルム。 A retardation layer having an in-plane retardation Re (550) of 100 nm to 200 nm, which is disposed on the opposite side of the polarizer from the window; and a slow axis of the retardation layer and a transmission axis of the polarizer The antiglare film for windows according to any one of claims 1 to 4, wherein an angle between the window and the window is 38 ° to 52 °.
  6. 　前記偏光子の前記窓側に配置される、面内位相差Ｒｅ（５５０）が１８０ｎｍ～３２０ｎｍである別の位相差層をさらに含み、該別の位相差層の遅相軸と該偏光子の透過軸とのなす角度が３８°～５２°である、請求項１から５のいずれかに記載の窓用ギラツキ防止フィルム。 And further including another retardation layer disposed on the window side of the polarizer and having an in-plane retardation Re (550) of 180 nm to 320 nm, and the slow axis of the other retardation layer and the transmission of the polarizer The antiglare film for windows according to any one of claims 1 to 5, wherein an angle formed with the shaft is 38 ° to 52 °.
PCT/JP2019/014781 2018-04-18 2019-04-03 Window glare prevention film WO2019202987A1 (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11131945A (en) * 1997-10-31 1999-05-18 Minnesota Mining & Mfg Co <3M> Dimmer
WO2015134609A1 (en) * 2014-03-05 2015-09-11 5.11, Inc. Tactical circular polarized eyewear
JP2017021124A (en) * 2015-07-09 2017-01-26 大日本印刷株式会社 Dimmer and dimming plate
JP2017534076A (en) * 2014-10-17 2017-11-16 スリーエム イノベイティブ プロパティズ カンパニー Multilayer optical film with overlapping harmonics

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11131945A (en) * 1997-10-31 1999-05-18 Minnesota Mining & Mfg Co <3M> Dimmer
WO2015134609A1 (en) * 2014-03-05 2015-09-11 5.11, Inc. Tactical circular polarized eyewear
JP2017534076A (en) * 2014-10-17 2017-11-16 スリーエム イノベイティブ プロパティズ カンパニー Multilayer optical film with overlapping harmonics
JP2017021124A (en) * 2015-07-09 2017-01-26 大日本印刷株式会社 Dimmer and dimming plate

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