WO2022102166A1 - Procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase - Google Patents

Procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase Download PDF

Info

Publication number
WO2022102166A1
WO2022102166A1 PCT/JP2021/025057 JP2021025057W WO2022102166A1 WO 2022102166 A1 WO2022102166 A1 WO 2022102166A1 JP 2021025057 W JP2021025057 W JP 2021025057W WO 2022102166 A1 WO2022102166 A1 WO 2022102166A1
Authority
WO
WIPO (PCT)
Prior art keywords
retardation layer
polarizing plate
layer
liquid crystal
water
Prior art date
Application number
PCT/JP2021/025057
Other languages
English (en)
Japanese (ja)
Inventor
拓弥 南原
理 小島
周作 後藤
Original Assignee
日東電工株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日東電工株式会社 filed Critical 日東電工株式会社
Priority to CN202180076084.5A priority Critical patent/CN116438060A/zh
Publication of WO2022102166A1 publication Critical patent/WO2022102166A1/fr

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B38/00—Ancillary operations in connection with laminating processes
    • B32B38/18—Handling of layers or the laminate
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/02—Physical, chemical or physicochemical properties
    • B32B7/023—Optical properties
    • 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 a method for manufacturing a polarizing plate with a retardation layer.
  • Image display devices represented by liquid crystal displays and electroluminescence (EL) display devices are rapidly becoming widespread.
  • a polarizing plate and a retardation plate are typically used in an image display device.
  • a polarizing plate with a retardation layer in which a polarizing plate and a retardation plate are integrated is widely used (for example, Patent Document 1).
  • Patent Document 1 a polarizing plate with a retardation layer in which a polarizing plate and a retardation plate are integrated is widely used.
  • Patent Document 1 a polarizing plate with a retardation layer in which a polarizing plate and a retardation plate are integrated
  • the thin polarizing plate with a retardation layer has a problem that warpage is likely to occur.
  • the problem of warpage is remarkable in a polarizing plate with a retardation layer, which has a protective layer having a small moisture permeability on only one side of the polarizing element and includes a retardation layer which is an orientation-solidifying layer of a liquid crystal compound.
  • the present invention has been made to solve the above-mentioned conventional problems, and a main object thereof is to provide a simple and efficient method for manufacturing a polarizing plate with a retardation layer in which warpage is suppressed.
  • Manufacturing method is provided. The manufacturing method is to humidify an intermediate laminate having a water-absorbent film temporarily attached to the retard layer side of a polarizing plate with a retardation layer while transporting it in a roll; the humidified intermediate laminate is stored for 12 hours or more.
  • the protective layer has a moisture permeability of 100 g / m 2.24 h or less at 40 ° C. and 92% RH, and the retardation layer is an oriented solidified layer of a liquid crystal compound.
  • the water absorption rate of the water-absorbent film is 2% or more. In one embodiment, the water-absorbent film is a triacetyl cellulose film. In one embodiment, the thickness of the water-absorbent film is 40 ⁇ m or more. In one embodiment, the water-absorbent film has a moisture permeability of 300 g / m 2.24 h or more at 40 ° C. and 92% RH. In one embodiment, the humidification treatment is performed in an environment where the temperature is 34 ° C. or lower and the amount of water vapor is 13.8 g / m 3 or more. In one embodiment, the humidification time in the humidification treatment is 5 minutes or more.
  • the humidified intermediate laminate has a storage time of 24 hours or more. In one embodiment, the humidified intermediate laminate is stored in an environment where the temperature is 34 ° C. or lower. In one embodiment, the manufacturing method further comprises stripping and removing the water-absorbent film from the intermediate laminate after storage.
  • the retardation layer has a moisture permeability of 300 g / m 2.24 h or more at 40 ° C. and 92% RH. In one embodiment, the retardation layer is a single layer, the Re (550) of the retardation layer is 100 nm to 190 nm, and the Re (450) / Re (550) of the retardation layer is 0.
  • the angle formed by the slow axis of the retardation layer and the absorption axis of the polarizing element is 40 ° to 50 °.
  • the retardation layer has a laminated structure of an oriented solidified layer of a first liquid crystal compound and an oriented solidified layer of a second liquid crystal compound; an oriented solidified layer of the first liquid crystal compound.
  • Re (550) of the second liquid crystal compound is 200 nm to 300 nm, and the angle formed by the slow axis thereof and the absorption axis of the above-mentioned polarizing element is 10 ° to 20 °; Re (550) of the oriented solidification layer of the second liquid crystal compound. ) Is 100 nm to 190 nm, and the angle formed by the slow axis thereof and the absorption axis of the substituent is 70 ° to 80 °. In one embodiment, the total thickness of the polarizing plate with a retardation layer is 45 ⁇ m or less.
  • an intermediate laminate temporarily coated with a predetermined water-absorbent film is subjected to a predetermined humidification treatment, and the humidified intermediate laminate is predetermined.
  • Refractive index (nx, ny, nz) "Nx" is the refractive index in the direction in which the refractive index in the plane is maximized (that is, the direction of the slow phase axis), and "ny” is the direction orthogonal to the slow phase axis in the plane (that is, the direction of the phase advance axis). Is the refractive index of, and "nz” is the refractive index in the thickness direction.
  • In-plane phase difference (Re) “Re ( ⁇ )” is an in-plane phase difference measured with light having a wavelength of ⁇ nm at 23 ° C.
  • Re (550) is an in-plane phase difference measured with light having a wavelength of 550 nm at 23 ° C.
  • Phase difference in the thickness direction (Rth) is a phase difference in the thickness direction measured with light having a wavelength of ⁇ nm at 23 ° C.
  • Rth (550) is a phase difference in the thickness direction measured with light having a wavelength of 550 nm at 23 ° C.
  • FIG. 1 is a schematic cross-sectional view showing an example of the polarizing plate with a retardation layer obtained by the manufacturing method according to the embodiment of the present invention.
  • the polarizing plate 100 with a retardation layer in the illustrated example has a polarizing element 11, a protective layer 12 arranged on one side of the polarizing element 11 (typically, the viewing side), and the other side of the polarizing element 11. It has a retardation layer 20 arranged in the.
  • the polarizing plate 100 with a retardation layer has a protective layer 12 only on the visible side (opposite side of the retardation layer 20) of the polarizing element 11.
  • the effect (described later) according to the embodiment of the present invention can be remarkable.
  • an adhesive layer (not shown) is provided on the opposite side of the retardation layer 20 from the polarizing element 11 (that is, as the outermost layer on the side opposite to the visual recognition side), and the polarizing plate with the retardation layer is an image. It can be pasted on the display panel.
  • a release film (not shown) is temporarily attached to the surface of the pressure-sensitive adhesive layer until the polarizing plate with a retardation layer is used.
  • the release film By temporarily attaching the release film, the pressure-sensitive adhesive layer can be protected and a roll of the polarizing plate with a retardation layer can be formed.
  • a laminated body of a polarizing element and a protective layer may be referred to as a polarizing plate.
  • the moisture permeability of the protective layer 12 at 40 ° C. and 92% RH (hereinafter, simply referred to as moisture permeability) is 100 g / m 2.24 h or less.
  • the moisture permeability of the protective layer is preferably 80 g / m 2.24 h or less, and more preferably 60 g / m 2.24 h or less.
  • the lower limit of the moisture permeation may be, for example, 5 g / m 2.24 h.
  • the retardation layer 20 is an oriented solidified layer (liquid crystal oriented solidified layer) of a liquid crystal compound.
  • a liquid crystal compound By using a liquid crystal compound, the difference between nx and ny of the obtained retardation layer can be significantly increased as compared with the non-liquid crystal material, so that the thickness of the retardation layer for obtaining a desired in-plane retardation can be obtained. Can be made much smaller. Therefore, it is possible to realize a remarkable reduction in thickness of the polarizing plate with a retardation layer. In such a polarizing plate with a retardation layer, the effect (described later) according to the embodiment of the present invention can be remarkable.
  • the term "aligned solidified layer” refers to a layer in which a liquid crystal compound is oriented in a predetermined direction within the layer and the oriented state is fixed.
  • the "oriented solidified layer” is a concept including an oriented cured layer obtained by curing a liquid crystal monomer as described later.
  • the rod-shaped liquid crystal compounds are typically oriented in a state of being aligned in the slow axis direction of the retardation layer (homogeneous orientation).
  • the retardation layer 20 may be a single layer as shown in FIG. 1, or may have a laminated structure of two or more layers as shown in FIG.
  • the moisture permeability of the retardation layer is preferably 300 g / m 2.24 h or more, more preferably 300 g / m 2.24 h to 1000 g / m 2.24 h, and further preferably 400 g / m 2.24 h to 800 g. / M 2.24h .
  • the difference between the moisture permeability of the protective layer and the moisture permeability of the retardation layer is preferably 200 g / m 2.24 h or more, and more preferably 250 g / m 2.24 h to 750 g / m 2.24 h.
  • the total thickness of the polarizing plate with a retardation layer (total thickness of the polarizing element, the protective layer, the retardation layer, and the adhesive layer in which these are laminated) is preferably 45 ⁇ m or less, more preferably 40 ⁇ m or less, and further preferably. Is 35 ⁇ m or less.
  • the total thickness of the polarizing plate with a retardation layer can be, for example, 25 ⁇ m or more.
  • the ratio of the thickness of the polarizing plate (polarizer and the protective layer) to the thickness of the retardation layer (polarizing plate / retardation layer: hereinafter, may be simply referred to as "thickness ratio".
  • Such a thickness ratio can be realized by having a protective layer on only one side of the polarizing element, the retardation layer being an orientation-solidifying layer of the liquid crystal compound, and the thickness of the polarizing element being thin as described later.
  • the polarizing plate with a retardation layer may further include other optical functional layers.
  • the type, characteristics, number, combination, arrangement position, and the like of the optical functional layers that can be provided on the polarizing plate with a retardation layer can be appropriately set according to the purpose.
  • the polarizing plate with a retardation layer may further have a conductive layer or an isotropic substrate with a conductive layer (neither is shown).
  • the conductive layer or the isotropic base material with the conductive layer is typically provided on the outside of the retardation layer 20 (on the opposite side of the polarizing plate 10).
  • the conductive layer or the isotropic base material with the conductive layer is typically any layer provided as needed, and may be omitted.
  • the polarizing plate with a retardation layer is a so-called inner in which a touch sensor is incorporated between an image display cell (for example, an organic EL cell) and the polarizing plate. It can be applied to a touch panel type input display device.
  • the polarizing plate with a retardation layer may further include another retardation layer.
  • the optical characteristics for example, refractive index characteristics, in-plane retardation, Nz coefficient, photoelastic coefficient
  • thickness, arrangement position, and the like of the other retardation layer can be appropriately set according to the purpose.
  • the surface of the protective layer 12 is provided with a layer (typically, a (elliptical) circular polarization function) for improving visibility when visually recognizing through polarized sunglasses.
  • a layer typically, a (elliptical) circular polarization function
  • a plate, an ultra-high retardation layer may be provided. With such a configuration, excellent visibility can be realized even when the display screen is visually recognized through a polarizing lens such as polarized sunglasses. Therefore, the polarizing plate with a retardation layer can be suitably applied to an image display device that can be used outdoors.
  • Polarizers can be made by any suitable method.
  • the polarizing plate may contain a polarizing element made of a single-layer resin film, or may contain a polarizing element made of a laminated body having two or more layers.
  • a method for producing a polarizing plate from a single-layer resin film is typically a resin film with iodine, a dichroic dye, or the like. It includes performing a dyeing treatment with a color substance and a stretching treatment.
  • the resin film include a hydrophilic polymer film such as a polyvinyl alcohol (PVA) -based film, a partially formalized PVA-based film, and an ethylene / vinyl acetate copolymer-based partially saponified film.
  • the method may further include insolubilization treatment, swelling treatment, cross-linking treatment and the like.
  • a polarizing plate can be obtained by laminating a protective layer (protective film) on at least one of the obtained polarizing elements. Since such a manufacturing method is well-known and customary in the art, detailed description thereof will be omitted.
  • the laminate is a resin base material and a PVA-based resin layer (PVA-based) laminated on the resin base material. It may be a laminate with a resin film), or it may be a laminate of a resin base material and a PVA-based resin layer coated and formed on the resin base material.
  • PVA-based resin layer PVA-based resin layer coated and formed on the resin base material.
  • a PVA-based resin solution is applied to a resin base material and dried to form a PVA-based resin layer on the resin base material, and the resin base material and the PVA-based resin layer are laminated.
  • a polyvinyl alcohol-based resin layer containing a halide and a polyvinyl alcohol-based resin is preferably formed on one side of the resin base material.
  • Stretching typically involves immersing the laminate in an aqueous boric acid solution for stretching. Further, stretching may further comprise, if necessary, stretching the laminate in the air at a high temperature (eg, 95 ° C.
  • the laminate is subjected to a drying shrinkage treatment in which the laminate is shrunk by 2% or more in the width direction by heating while being conveyed in the longitudinal direction.
  • the production method includes subjecting the laminate to an aerial auxiliary stretching treatment, a dyeing treatment, an underwater stretching treatment, and a drying shrinkage treatment in this order.
  • the optical characteristics can be improved by shrinking the laminated body in the width direction by the drying shrinkage treatment.
  • the obtained resin base material / polarizing element laminate may be used as it is (that is, the resin base material may be used as a protective layer for the polarizing element), and the resin base material is peeled off from the resin base material / polarizing element laminate. Then, an arbitrary appropriate protective layer according to the purpose may be laminated on the peeled surface and used. Details of the method for producing such a polarizing element are described in, for example, Japanese Patent Application Laid-Open No. 2012-73580 and Japanese Patent No. 6470455. The entire description of these publications is incorporated herein by reference.
  • a retardation layer (liquid crystal oriented solidified layer)
  • the surface of a predetermined base material is subjected to an orientation treatment, and a coating liquid containing a liquid crystal compound is applied to the surface to orient the liquid crystal compound in a direction corresponding to the alignment treatment. It can be formed by fixing the state.
  • the orientation treatment any appropriate orientation treatment can be adopted. Specific examples thereof include mechanical orientation treatment, physical orientation treatment, and chemical orientation treatment. Specific examples of the mechanical orientation treatment include a rubbing treatment and a stretching treatment. Specific examples of the physical orientation treatment include magnetic field orientation treatment and electric field orientation treatment. Specific examples of the chemical alignment treatment include an orthorhombic vapor deposition method and a photoalignment treatment.
  • the treatment conditions for various orientation treatments any appropriate conditions may be adopted depending on the purpose.
  • the orientation of the liquid crystal compound is performed by treating at a temperature indicating the liquid crystal phase according to the type of the liquid crystal compound. By performing such temperature treatment, the liquid crystal compound takes a liquid crystal state, and the liquid crystal compound is oriented according to the orientation treatment direction of the surface of the substrate.
  • the alignment state is fixed by cooling the liquid crystal compound oriented as described above.
  • the orientation state is fixed by subjecting the liquid crystal compound oriented as described above to a polymerization treatment or a crosslinking treatment.
  • liquid crystal compound and details of the method for forming the oriented solidified layer are described in Japanese Patent Application Laid-Open No. 2006-163343. The description of this publication is incorporated herein by reference.
  • the liquid crystal oriented solidified layer is formed on the base material.
  • a polarizing plate with a retardation layer can be obtained by laminating the polarizing plate obtained above and the retardation layer.
  • the lamination of the polarizing plate and the retardation layer is typically performed while transporting them in a roll (that is, by so-called roll-to-roll).
  • Lamination can be typically performed by transferring a liquid crystal oriented solidified layer formed on the substrate.
  • each retardation layer may be sequentially laminated (transferred) on the polarizing plate, or the laminated body of the retardation layer may be laminated (transferred) on the polarizing plate. Transfer is typically carried out via an active energy ray-curable adhesive.
  • the thickness of the active energy ray-curable adhesive after curing is preferably 0.4 ⁇ m or more, more preferably 0.4 ⁇ m to 3.0 ⁇ m, and further preferably 0.6 ⁇ m to 1.5 ⁇ m.
  • the polarizing plate with a retardation layer further includes other optical functional layers (eg, a conductive layer, another retardation layer), these optical functional layers are laminated or formed in a predetermined arrangement position by any suitable method. obtain.
  • other optical functional layers eg, a conductive layer, another retardation layer
  • the production (lamination) of the polarizing plate with a retardation layer is typically performed in an environment where the amount of water vapor is 11.5 g / m 3 or less.
  • the amount of water vapor in the lamination is preferably 6.0 g / m 3 to 11.5 g / m 3 , and more preferably 8.0 g / m 3 to 11.5 g / m 3 .
  • Such an amount of water vapor in the lamination can be realized, for example, by changing the relative humidity according to the temperature in the temperature range of 18 ° C. to 25 ° C.
  • the amount of water vapor can be achieved, for example, by setting the relative humidity to 65% RH or less when the temperature is 18 ° C; and also, for example, when the temperature is 20 ° C, the relative humidity is 55% RH. It can be realized by setting the relative humidity to 45% RH or less, for example, when the temperature is 23 ° C.
  • the lower limit of relative humidity can be, for example, 30% RH.
  • the water-absorbent film 150 is temporarily attached to the retardation layer side of the polarizing plate with the retardation layer obtained above to prepare the intermediate laminate 200.
  • the intermediate laminate is produced by roll-to-roll in the same manner as described above.
  • the polarizing plate with a retardation layer at the time of producing the intermediate laminate has the same layer structure as the polarizing plate with a retardation layer finally obtained, but is substantially an intermediate, so that it is shown in FIG.
  • the intermediate corresponding to the polarizing plate with a retardation layer 100 in FIG. 1 is indicated by reference numeral 100'
  • the intermediate corresponding to the polarizing plate with a retardation layer 101 in FIG. 2 is indicated by reference numeral 101'.
  • the water absorption rate of the water-absorbent film is preferably 2% or more, more preferably 2% to 20%, and further preferably 2% to 10%.
  • the amount of water that can reach the polarizing element can be adjusted to an appropriate range by the humidification treatment and storage after the humidification treatment (both described later). More specifically, the water-absorbent film can absorb an appropriate amount of water by the humidification treatment and retain a predetermined amount of the absorbed water. Moisture retained in the water-absorbent film can transfer to the polarizing element during storage.
  • the conditions of the humidification treatment are appropriately set to adjust the amount of water absorbed and retained in the water-absorbent film, and the storage conditions are appropriately adjusted to adjust the amount of water transferred from the water-absorbent film to the polarizing element.
  • the water content of the stator can be set in an appropriate range.
  • the warp of the polarizing plate with a retardation layer can be remarkably suppressed. If the water absorption rate is too low, the suppression of warpage may be insufficient. If the water absorption is too high, warpage may occur in the opposite direction and / or in the plane in a direction orthogonal to the initial direction.
  • the polarizing plate with a retardation layer typically causes a convex warp on the protective layer side.
  • a convex warp is generated on the retardation layer side.
  • the warpage in the opposite directions is canceled out, so that the warp can be suppressed in the obtained polarizing plate with a retardation layer. Therefore, if the water absorption rate is too high, the convex warp toward the retardation layer side becomes too large, and the obtained polarizing plate with the retardation layer has the opposite direction (convex toward the protective layer side) and / or the initial direction in the plane. Can cause warpage in orthogonal directions.
  • the water-absorbent film can be made of any suitable material as long as it has the above-mentioned desired water absorption rate.
  • Examples of the material constituting the water-absorbent film include triacetyl cellulose (TAC) and an acrylic resin. TAC is preferable.
  • the thickness of the water-absorbent film is preferably 40 ⁇ m or more, more preferably 60 ⁇ m or more, and further preferably 70 ⁇ m or more.
  • the upper limit of the thickness of the water-absorbent film can be, for example, 200 ⁇ m. If the thickness of the water-absorbent film is within such a range, the amount of water that can reach the polarizing element in the humidification treatment can be adjusted to an appropriate range by a synergistic effect with the effect of setting the water absorption rate within a predetermined range. Therefore, storage after the humidification treatment can bring the water content of the stator to an appropriate range. As a result, the warp of the polarizing plate with a retardation layer can be remarkably suppressed.
  • the moisture permeability of the water-absorbent film is preferably 300 g / m 2.24 h or more, more preferably 300 g / m 2.24 h to 1000 g / m 2.24 h, and further preferably 300 g / m 2.24 h to 800 g. / M 2.24h . If the moisture permeability of the water-absorbent film is within such a range, an appropriate amount of the water absorbed by the water-absorbent film by the humidification treatment and retained in the water-absorbent film becomes a polarizing element by storage after the humidification treatment. Can be migrated. Therefore, by storing after the humidification treatment, the water content of the polarizing element can be set in an appropriate range. As a result, the warp of the polarizing plate with a retardation layer can be remarkably suppressed.
  • the production (lamination) of the intermediate laminate can be typically performed in the same environment as the production (lamination) of the polarizing plate with a retardation layer.
  • the intermediate laminate 200 obtained above is subjected to a humidification treatment.
  • the humidification treatment is typically performed while the intermediate laminate is being rolled and conveyed.
  • the humidification treatment is typically performed in an environment where the temperature is 34 ° C. or lower and the amount of water vapor is 13.8 g / m 3 or more.
  • the temperature in the humidification treatment is preferably 18 ° C to 34 ° C.
  • the amount of water vapor in the humidification treatment is preferably 13.8 g / m 3 to 30 g / m 3 , and more preferably 13.8 g / m 3 to 24 g / m 3 .
  • Such an amount of water vapor in the humidification treatment can be achieved, for example, by setting the relative humidity to 80% RH or higher when the temperature is 20 ° C; and also, for example, when the temperature is 23 ° C. It can be achieved by setting the relative humidity to 70% RH or higher; and for example, if the temperature is 25 ° C, it can be achieved by setting the relative humidity to 60% RH or higher; and for example, the temperature is 28 ° C. If so, it can be achieved by increasing the relative humidity to more than 50% RH.
  • the upper limit of relative humidity can be, for example, 100% RH.
  • the humidification time in the humidification treatment is preferably 5 minutes or more, more preferably 5 minutes to 30 minutes, still more preferably 5 minutes to 20 minutes, and particularly preferably 5 minutes to 15 minutes. If the humidification time is 5 minutes or more, the desired amount of water absorption can be achieved. Since the effect does not change even if the humidification time becomes excessively long, the upper limit of the humidification time can be determined by the balance between the desired amount of water absorption and the production efficiency.
  • the humidification treatment is performed so that the weight per unit volume of the polarizing plate with a retardation layer is increased by, for example, 0.2% or more.
  • the weight increase per unit volume of the polarizing plate with a retardation layer in the humidification treatment is preferably 0.2% to 2.5%, more preferably 0.3% to 2.0%, still more preferably. It is 0.3% to 1.0%.
  • the weight increase in the humidification treatment means that the polarizing plate with a retardation layer has absorbed water. Therefore, by setting the weight increase amount in such a range, the polarizing element can absorb a desired amount of water. .. As a result, the warp of the polarizing plate with a retardation layer can be suppressed.
  • the humidified intermediate laminate is stored as shown in FIG.
  • the intermediate laminate is wound into a roll and stored in a roll state.
  • the moisture imparted to the intermediate laminate (substantially, the water-absorbent film) by the humidification treatment can be satisfactorily transferred to the polarizing element.
  • the water content of the polarizing element can be increased, and as a result, the warp of the polarizing plate with a retardation layer can be suppressed.
  • the storage time is 12 hours or more, preferably 16 hours or more, more preferably 24 hours or more, still more preferably 30 hours or more, as described above. Since the effect does not change even if the storage time becomes excessively long, the upper limit of the storage time can be determined by the balance between the desired amount of water absorption and the production efficiency.
  • Storage can typically be done near room temperature.
  • the temperature in storage is typically 34 ° C. or lower, preferably 30 ° C. or lower, more preferably 20 ° C. to 30 ° C., and even more preferably 23 ° C. to 27 ° C. If the storage temperature is too high, the water imparted (absorbed) to the polarizing plate with a retardation layer by the humidification treatment evaporates to the outside, and may not be transferred to the polarizing element satisfactorily.
  • Storage is typically performed in an environment with a water vapor content of 11.5 g / m 3 or less. In other words, storage takes place without substantially humidifying the intermediate laminate. By storing in such an environment, moisture can be satisfactorily transferred from the water-absorbent film to the polarizing element.
  • the water-absorbent film After storage, the water-absorbent film is peeled off from the intermediate laminate as shown in FIG. In this way, a polarizing plate with a retardation layer can be obtained.
  • the splitter 11 is typically a resin film containing a dichroic substance (for example, iodine).
  • a dichroic substance for example, iodine
  • examples of the resin film include a hydrophilic polymer film such as a polyvinyl alcohol (PVA) -based film, a partially formalized PVA-based film, and an ethylene / vinyl acetate copolymer-based partially saponified film.
  • PVA polyvinyl alcohol
  • the thickness of the splitter is preferably 15 ⁇ m or less, more preferably 1 ⁇ m to 12 ⁇ m, and further preferably 3 ⁇ m to 12 ⁇ m.
  • a desired amount of water can be satisfactorily absorbed by the humidification treatment as described above.
  • the splitter preferably exhibits absorption dichroism at any wavelength of 380 nm to 780 nm.
  • the simple substance transmittance of the substituent is, for example, 41.5% to 46.0%, preferably 42.0% to 46.0%, and preferably 44.5% to 46.0%.
  • the degree of polarization of the polarizing element is preferably 97.0% or more, more preferably 99.0% or more, and further preferably 99.9% or more.
  • the protective layer 12 is formed of any suitable film that can be used as a protective layer for a polarizing element as long as it has the above-mentioned moisture permeability.
  • the material that is the main component of the film include polyester-based, polyvinyl alcohol-based, polycarbonate-based, polyamide-based, polyimide-based, polyethersulfone-based, polysulfone-based, polystyrene-based, and cyclic olefin-based (for example, polynorbornene-based). ), Polystyrene-based, (meth) acrylic-based, acetate-based transparent resins and the like.
  • the protective layer 12 may be composed of a cyclic olefin-based (eg, polynorbornene-based) resin film.
  • the polarizing plate with a retardation layer obtained by the manufacturing method of the embodiment of the present invention is typically arranged on the visible side of an image display device, and the protective layer 12 is arranged on the visible side thereof. Therefore, the protective layer 12 may be subjected to surface treatment such as hard coat treatment, antireflection treatment, sticking prevention treatment, and antiglare treatment, if necessary.
  • the thickness of the protective layer 12 is preferably 5 ⁇ m to 80 ⁇ m, more preferably 10 ⁇ m to 40 ⁇ m, and even more preferably 15 ⁇ m to 35 ⁇ m. When the surface treatment is applied, the thickness of the protective layer 12 is the thickness including the thickness of the surface treatment layer.
  • phase difference layer 20 may be a single layer or may have a laminated structure of two or more layers.
  • the retardation layer 20 can function as a ⁇ / 4 plate in one embodiment.
  • the Re (550) of the retardation layer is preferably 100 nm to 180 nm, more preferably 110 nm to 170 nm, and further preferably 110 nm to 160 nm.
  • the thickness of the retardation layer can be adjusted to obtain the desired in-plane retardation of the ⁇ / 4 plate.
  • the thickness of the retardation layer can be, for example, 1.0 ⁇ m to 2.5 ⁇ m.
  • the angle formed by the slow axis of the retardation layer and the absorption axis of the polarizing element is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, and even more preferably 44. ° to 46 °.
  • the retardation layer preferably exhibits a reverse dispersion wavelength characteristic in which the retardation value increases with the wavelength of the measurement light.
  • the retardation layer 20 When the retardation layer 20 has a laminated structure, the retardation layer typically has a two-layer structure of an H layer 21 and a Q layer 22 in order from the polarizing plate side as shown in FIG.
  • the H layer can typically function as a ⁇ / 2 plate
  • the Q layer can typically function as a ⁇ / 4 plate.
  • the Re (550) of the H layer is preferably 200 nm to 300 nm, more preferably 220 nm to 290 nm, still more preferably 230 nm to 280 nm; and the Re (550) of the Q layer is preferably.
  • the thickness of the H layer can be adjusted to obtain the desired in-plane phase difference of the ⁇ / 2 plate.
  • the thickness of the H layer can be, for example, 2.0 ⁇ m to 4.0 ⁇ m.
  • the thickness of the Q layer can be adjusted to obtain the desired in-plane phase difference of the ⁇ / 4 plate.
  • the thickness of the Q layer can be, for example, 1.0 ⁇ m to 2.5 ⁇ m.
  • the angle formed by the slow phase axis of the H layer and the absorption axis of the polarizing element is preferably 10 ° to 20 °, more preferably 12 ° to 18 °, and even more preferably 12 °.
  • the angle between the slow axis of the Q layer and the absorption axis of the stator is preferably 70 ° to 80 °, more preferably 72 ° to 78 °, and even more preferably 72 °. It is ⁇ 76 °.
  • the arrangement order of the H layer and the Q layer may be reversed, and the angle formed by the slow axis of the H layer and the absorption axis of the stator and the slow axis of the Q layer and the absorption axis of the splitter are formed.
  • each layer for example, H layer and Q layer
  • each layer may exhibit a reverse dispersion wavelength characteristic in which the retardation value increases according to the wavelength of the measurement light, and the retardation value may be exhibited. May show a positive wavelength dispersion characteristic that decreases according to the wavelength of the measurement light, or may show a flat wavelength dispersion characteristic in which the phase difference value hardly changes depending on the wavelength of the measurement light.
  • the Nz coefficient of the retardation layer is preferably 0.9 to 1.5, and more preferably 0.9 to 1.3.
  • the retardation layer is a liquid crystal oriented solidifying layer as described above.
  • the liquid crystal compound include a liquid crystal compound (nematic liquid crystal) in which the liquid crystal phase is a nematic phase.
  • a liquid crystal compound for example, a liquid crystal polymer or a liquid crystal monomer can be used.
  • the liquid crystal expression mechanism of the liquid crystal compound may be either lyotropic or thermotropic.
  • the liquid crystal polymer and the liquid crystal monomer may be used alone or in combination.
  • the liquid crystal monomer is preferably a polymerizable monomer and a crosslinkable monomer. This is because the orientation state of the liquid crystal monomer can be fixed by polymerizing or cross-linking (that is, curing) the liquid crystal monomer. After the liquid crystal monomers are oriented, for example, if the liquid crystal monomers are polymerized or crosslinked with each other, the oriented state can be fixed.
  • the polymer is formed by polymerization, and the three-dimensional network structure is formed by crosslinking, but these are non-liquid crystal.
  • the formed retardation layer does not undergo a transition to a liquid crystal phase, a glass phase, or a crystal phase due to a temperature change peculiar to a liquid crystal compound, for example.
  • the retardation layer becomes an extremely stable retardation layer that is not affected by temperature changes.
  • the temperature range in which the liquid crystal monomer exhibits liquid crystal properties differs depending on the type. Specifically, the temperature range is preferably 40 ° C. to 120 ° C., more preferably 50 ° C. to 100 ° C., and most preferably 60 ° C. to 90 ° C.
  • any suitable liquid crystal monomer can be adopted as the liquid crystal monomer.
  • the polymerizable mesogen compounds described in Special Tables 2002-533742 WO00 / 37585
  • EP358208 US5211877
  • EP66137 US43884553
  • WO93 / 22397 EP0261712, DE19504224, DE4408171, and GB2280445
  • Specific examples of such a polymerizable mesogen compound include, for example, BASF's trade name LC242, Merck's trade name E7, and Wacker-Chem's trade name LC-Silicon-CC3767.
  • the liquid crystal monomer for example, a nematic liquid crystal monomer is preferable.
  • the change in the amount of warpage is ⁇ 25 mm or less
  • ⁇ The change in the amount of warpage is greater than ⁇ 25 mm. Is represented by "negative (-)".
  • the stationary surface side is the retardation layer (Q layer) side.
  • Example 1 Fabrication of Polarizing Plate
  • a thermoplastic resin base material an amorphous isophthal copolymerized polyethylene terephthalate film (thickness: 100 ⁇ m) having a Tg of about 75 ° C. was used, and one side of the resin base material was treated with corona. Was given. 100 parts by weight of PVA-based resin in which polyvinyl alcohol (polymerization degree 4200, saponification degree 99.2 mol%) and acetacetyl-modified PVA (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "Gosefimer”) are mixed at a ratio of 9: 1.
  • a PVA aqueous solution (coating solution) was prepared by dissolving 13 parts by weight of potassium iodide in water.
  • the PVA aqueous solution was applied to the corona-treated surface of the resin base material and dried at 60 ° C. to form a PVA-based resin layer having a thickness of 13 ⁇ m, and a laminate was prepared.
  • the obtained laminate was uniaxially stretched 2.4 times in the vertical direction (longitudinal direction) in an oven at 130 ° C. (aerial auxiliary stretching treatment). Next, the laminate was immersed in an insolubilizing bath at a liquid temperature of 40 ° C.
  • boric acid aqueous solution obtained by blending 3 parts by weight of potassium iodide and 5 parts by weight of boric acid with respect to 100 parts by weight of water
  • a boric acid aqueous solution obtained by blending 3 parts by weight of potassium iodide and 5 parts by weight of boric acid with respect to 100 parts by weight of water
  • a boric acid aqueous solution boric acid concentration 4% by weight, potassium iodide concentration 5% by weight
  • Uniaxial stretching was performed so that the stretching ratio was 5.5 times (underwater stretching treatment).
  • the laminate was immersed in a washing bath having a liquid temperature of 20 ° C.
  • an HC-COP film was attached to the surface of the obtained polarizing element (the surface opposite to the resin base material) as a protective layer on the visible side via an ultraviolet curable adhesive.
  • the HC-COP film is a film in which an HC layer (thickness 2 ⁇ m) is formed on a cycloolefin resin (COP) film (thickness 25 ⁇ m), and the COP film is bonded so as to be on the splitter side.
  • the resin base material was peeled off to obtain a polarizing plate having an HC-COP film (visible side protective layer) / polarizing element.
  • the moisture permeability of the protective layer on the visual recognition side was 100 g / m 2.24 h.
  • Phase Difference Layer 10 g of polymerizable liquid crystal (manufactured by BASF: trade name "Pariocolor LC242", represented by the following formula) showing a nematic liquid crystal phase and a photopolymerization initiator for the polymerizable liquid crystal compound (manufactured by BASF:
  • a liquid crystal composition (coating liquid) was prepared by dissolving 3 g of the trade name "Irgacure 907") in 40 g of toluene.
  • the surface of a polyethylene terephthalate (PET) film was rubbed with a rubbing cloth and subjected to an orientation treatment.
  • PET polyethylene terephthalate
  • the direction of the alignment treatment was set to be 15 ° when viewed from the visual recognition side with respect to the direction of the absorption axis of the polarizing element when the polarizing plate was attached.
  • the liquid crystal coating liquid was applied to the alignment-treated surface with a bar coater, and the liquid crystal compound was oriented by heating and drying at 90 ° C. for 2 minutes.
  • the liquid crystal layer thus formed was irradiated with light of 1 mJ / cm 2 using a metal halide lamp, and the liquid crystal layer was cured to form a liquid crystal oriented solidified layer A on the PET film.
  • the thickness of the liquid crystal oriented solidified layer A was 2.0 ⁇ m, and the in-plane retardation Re (550) was 270 nm.
  • the liquid crystal oriented solidified layer A was used as the H layer.
  • the liquid crystal oriented solidified layer B was formed.
  • the thickness of the liquid crystal oriented solidified layer B was 1.0 ⁇ m, and the in-plane retardation Re (550) was 140 nm.
  • the liquid crystal alignment solidification layer B was used as the Q layer.
  • a polarizing plate with a retardation layer having a structure of a protective layer / adhesive / polarizing element / adhesive / retardation layer (H layer) / adhesive / retardation layer (Q layer) was obtained.
  • the total thickness of the polarizing plate with a retardation layer was 38 ⁇ m.
  • the transfer (bonding) was performed while transporting the rolls.
  • Humidification treatment and storage 3 The intermediate laminate obtained in 1) was subjected to a humidification treatment while being transported by roll. The humidification treatment was carried out at 23 ° C. and 70% RH (water vapor content: 14.4 g / m 3 ) for 10 minutes. The humidified polarizing plate with a retardation layer was wound into a roll, and the roll was stored at 23 ° C. and 55% RH (water vapor content: 11.3 g / m 3 ) for 24 hours. The polarizing plates with a retardation layer before the humidification treatment and after the roll storage were subjected to the evaluation of (1) above, respectively. The results are shown in Table 1.
  • Example 2 A polarizing plate with a retardation layer was obtained in the same manner as in Example 1 except that the humidification treatment was carried out at 20 ° C. and 80% RH (water vapor amount was 13.8 / m 3 ) for 10 minutes.
  • the polarizing plates with a retardation layer before the humidification treatment and after the roll storage were subjected to the same evaluation as in Example 1, respectively. The results are shown in Table 1.
  • Example 1 A polarizing plate with a retardation layer was obtained in the same manner as in Example 1 except that the humidification treatment and the roll storage were performed without laminating the TAC film.
  • the polarizing plates with a retardation layer before the humidification treatment and after the roll storage were subjected to the same evaluation as in Example 1, respectively. The results are shown in Table 1.
  • Example 2 A polarizing plate with a retardation layer (before the production of the intermediate laminate) was obtained in the same manner as in Example 1.
  • the polarizing plate with a retardation layer was stored as it was (that is, without producing an intermediate laminate or subjected to a humidification treatment) and stored in a roll in the same manner as in Example 1.
  • the polarizing plates with a retardation layer after roll storage were subjected to the same evaluation as in Example 1. The results are shown in Table 1.
  • a TAC film (thickness 25 ⁇ m) is attached to the other surface of the polarizing element via a PVA-based adhesive to have a protective layer (HC-COP film) / polarizing element / protective layer (TAC film).
  • a polarizing plate was obtained. The following procedure is the same as in Example 1, and the protective layer (HC-COP film) / adhesive / polarizing element / adhesive / protective layer (TAC film) / adhesive / retardation layer (H layer) / adhesive.
  • a polarizing plate with a retardation layer having a configuration of a retardation layer (Q layer) was obtained. The total thickness of the polarizing plate with a retardation layer was 71 ⁇ m.
  • Example 1 The following procedure was the same as in Example 1, an intermediate laminate was prepared, the intermediate laminate was subjected to a humidification treatment, and then stored in a roll.
  • the polarizing plates with a retardation layer before the humidification treatment and after the roll storage were subjected to the same evaluation as in Example 1, respectively. The results are shown in Table 1.
  • the polarizing plate with a retardation layer obtained by the embodiment of the present invention is warped by subjecting the intermediate laminate to which the water-absorbent film is bonded to a predetermined humidification treatment and roll storage. It can be seen that it is suppressed. Further, as is clear from the reference example, it can be seen that such a warp is a problem peculiar to a polarizing plate with a retardation layer having a visible side protective layer having a thin total thickness and a small moisture permeability.
  • the polarizing plate with a retardation layer obtained by the manufacturing method of the embodiment of the present invention is used as a polarizing plate with a retardation layer for an image display device, and is particularly curved, bendable, foldable, or windable. It can be suitably used for an image display device (such an image display device typically uses a resin substrate as a substrate).
  • Typical examples of the image display device include a liquid crystal display device, an organic EL display device, and an inorganic EL display device.
  • Polarizer 12 Protective layer 20 Phase difference layer 21 Phase difference layer (H layer) 22 Phase difference layer (Q layer) 100 Polarizing plate with retardation layer 100'Polarizer with retardation layer (intermediate) 101 Polarizing plate with retardation layer 101'Polarizer with retardation layer (intermediate) 150 Water-absorbent film 200 Intermediate laminate

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Polarising Elements (AREA)
  • Laminated Bodies (AREA)

Abstract

L'invention concerne un procédé simple et efficace de production d'une plaque de polarisation équipée d'une couche à différence de phase dans laquelle la chaîne est supprimée. Dans un mode de réalisation de la présente invention, l'invention concerne un procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase ayant un polariseur, une couche protectrice positionnée sur un côté du polariseur, et une couche de différence de phase positionnée sur l'autre côté du polariseur. Ce procédé de production comprend : l'humidification d'un corps stratifié intermédiaire dans lequel un film absorbant l'eau est temporairement collé au côté couche de différence de phase de la plaque de polarisation équipée d'une couche à différence de phase, tout en transportant en rouleau le corps intermédiaire; et le stockage du corps stratifié intermédiaire humidifié pendant au moins 12 heures, la perméabilité à l'humidité de la couche protectrice à 40 °C et 92 % RH étant de 100 g/m2∙24 h ou moins, et la couche de différence de phase étant une couche solidifiée alignée d'un composé de cristaux liquides.
PCT/JP2021/025057 2020-11-11 2021-07-02 Procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase WO2022102166A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202180076084.5A CN116438060A (zh) 2020-11-11 2021-07-02 带相位差层的偏振片的制造方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2020187767A JP7565192B2 (ja) 2020-11-11 2020-11-11 位相差層付偏光板の製造方法
JP2020-187767 2020-11-11

Publications (1)

Publication Number Publication Date
WO2022102166A1 true WO2022102166A1 (fr) 2022-05-19

Family

ID=81601015

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2021/025057 WO2022102166A1 (fr) 2020-11-11 2021-07-02 Procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase

Country Status (4)

Country Link
JP (1) JP7565192B2 (fr)
CN (1) CN116438060A (fr)
TW (1) TW202219138A (fr)
WO (1) WO2022102166A1 (fr)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008015145A (ja) * 2006-07-05 2008-01-24 Seiko Epson Corp 偏光素子の製造方法、偏光素子、およびプロジェクタ
JP2009086047A (ja) * 2007-09-27 2009-04-23 Fujifilm Corp 偏光板及び液晶表示装置
JP2009258570A (ja) * 2007-05-08 2009-11-05 Nitto Denko Corp 粘着型光学フィルムおよび画像表示装置
JP2018205663A (ja) * 2017-06-09 2018-12-27 日東電工株式会社 位相差層付偏光板および画像表示装置
WO2019167926A1 (fr) * 2018-02-28 2019-09-06 富士フイルム株式会社 Corps multicouche, dispositif électroluminescent organique et dispositif d'affichage à cristaux liquides
JP2020024352A (ja) * 2018-07-31 2020-02-13 住友化学株式会社 円偏光板および表示装置
JP2020095255A (ja) * 2018-12-07 2020-06-18 住友化学株式会社 偏光板および表示装置
JP2020134934A (ja) * 2019-02-12 2020-08-31 住友化学株式会社 円偏光板およびそれを用いる有機ｅｌ表示装置

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008015145A (ja) * 2006-07-05 2008-01-24 Seiko Epson Corp 偏光素子の製造方法、偏光素子、およびプロジェクタ
JP2009258570A (ja) * 2007-05-08 2009-11-05 Nitto Denko Corp 粘着型光学フィルムおよび画像表示装置
JP2009086047A (ja) * 2007-09-27 2009-04-23 Fujifilm Corp 偏光板及び液晶表示装置
JP2018205663A (ja) * 2017-06-09 2018-12-27 日東電工株式会社 位相差層付偏光板および画像表示装置
WO2019167926A1 (fr) * 2018-02-28 2019-09-06 富士フイルム株式会社 Corps multicouche, dispositif électroluminescent organique et dispositif d'affichage à cristaux liquides
JP2020024352A (ja) * 2018-07-31 2020-02-13 住友化学株式会社 円偏光板および表示装置
JP2020095255A (ja) * 2018-12-07 2020-06-18 住友化学株式会社 偏光板および表示装置
JP2020134934A (ja) * 2019-02-12 2020-08-31 住友化学株式会社 円偏光板およびそれを用いる有機ｅｌ表示装置

Also Published As

Publication number Publication date
JP2022077101A (ja) 2022-05-23
TW202219138A (zh) 2022-05-16
JP7565192B2 (ja) 2024-10-10
CN116438060A (zh) 2023-07-14

Similar Documents

Publication Publication Date Title
JP6797499B2 (ja) 位相差層付偏光板およびそれを用いた画像表示装置
WO2021024544A1 (fr) Plaque de polarisation équipée d'une couche de retard et dispositif d'affichage d'image l'utilisant
JP2024007555A (ja) 位相差層付偏光板およびそれを用いた画像表示装置
JP7475241B2 (ja) 円偏光板の製造方法
TW202237382A (zh) 偏光板及偏光板的製造方法
WO2022102166A1 (fr) Procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase
JP7385380B2 (ja) 位相差層およびハードコート層付偏光板の製造方法
WO2022049847A1 (fr) Procédé de production d'une plaque de polarisation équipée d'une couche à différence de phase
JP6804168B2 (ja) 位相差層付偏光板およびそれを用いた画像表示装置
WO2022074872A1 (fr) Procédé de fabrication de plaque de polarisation équipée d'une couche à différence de phase
WO2022209791A1 (fr) Procédé de fabrication d'une plaque de polarisation équipée d'une couche à différence de phase et procédé de stockage pour plaque de polarisation équipée d'une couche à différence de phase
JP7566663B2 (ja) 積層体および画像表示パネルの製造方法
JP7572216B2 (ja) 位相差層付偏光板の製造方法および位相差層付偏光板の保管方法
JP2022106205A (ja) 積層体および位相差層付偏光板の製造方法
JP2022074936A (ja) 位相差層付偏光板の製造方法および位相差層付偏光板の保管方法
JP7288465B2 (ja) 偏光板およびその製造方法、ならびに該偏光板を用いた画像表示装置
WO2022091471A1 (fr) Plaque de polarisation équipée d'une couche de retard et dispositif d'affichage d'image
JP2023075748A (ja) 位相差層付偏光板およびそれを用いた画像表示装置
KR20240115165A (ko) 광학 적층체 및 해당 광학 적층체를 이용한 화상 표시 장치
JP2024101531A (ja) 光学積層体および該光学積層体を用いた画像表示装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21891414

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21891414

Country of ref document: EP

Kind code of ref document: A1