KR20220144876A - Circular polarizing plate with antireflection layer and image display device using the circular polarizing plate with antireflection layer - Google Patents

Abstract

In the present invention, there is provided a circularly polarizing plate with an antireflection layer capable of realizing an image display device having high transmittance and excellent durability in a high-temperature, high-humidity environment. A circularly polarizing plate with an antireflection layer according to an embodiment of the present invention includes a polarizing plate containing a polarizer, an antireflection layer disposed on one side of the polarizing plate, and a retardation layer disposed on the other side of the polarizing plate. The transmittance of the circularly polarizing plate with an antireflection layer is 45.5% or more, and the reflectance after 500 hours of heating and humidification test at 60 degreeC and 90%RH is 2.5% or less.

Description

Circular polarizing plate with antireflection layer and image display device using the circular polarizing plate with antireflection layer

The present invention relates to a circularly polarizing plate with an antireflection layer and an image display device using the circularly polarizing plate with an antireflection layer.

BACKGROUND ART In recent years, an image display device typified by a liquid crystal display device and an electroluminescent (EL) display device (eg, an organic EL display device, an inorganic EL display device) has spread rapidly. In an image display apparatus, the circularly polarizing plate containing a polarizing plate and a retardation plate may be used. About a circularly-polarizing plate, a circularly-polarizing plate with high transmittance|permeability is desired from a viewpoint of the low power consumption and brightness (luminance) of an image display apparatus (especially organic electroluminescent display apparatus). However, a circularly polarizing plate with a high transmittance|permeability may generate|occur|produce display nonuniformity (for example, a stripe) in an image display apparatus under a high temperature, high humidity environment.

Japanese Patent No. 5876441 Japanese Laid-Open Patent Publication No. 2014-0226266

The present invention has been made in order to solve the above conventional problems, and its main object is to provide an image display device having high transmittance and excellent durability in a high temperature and high humidity environment, and as a result, display unevenness is suppressed in a bright and high temperature and high humidity environment. It is to provide a circularly polarizing plate with an antireflection layer which can be realized.

A circularly polarizing plate with an antireflection layer according to an embodiment of the present invention includes a polarizing plate containing a polarizer, an antireflection layer disposed on one side of the polarizing plate, and a retardation layer disposed on the other side of the polarizing plate. The transmittance of the circularly polarizing plate with an antireflection layer is 45.5% or more, and the reflectance after 500 hours of heating and humidification test at 60°C and 90%RH is 2.5% or less.

In one embodiment, the said polarizer and the protective layer by the side of the said antireflection layer are bonded together via a 1st adhesive bond layer, The said polarizer and the said retardation layer are bonded via a 2nd adhesive bond layer, This 1st adhesive bond layer And at least one of the adhesive agent of this 2nd adhesive bond layer is comprised from the active energy ray hardening-type adhesive agent composition. The active energy ray-curable adhesive composition has an active energy ray-curable compound (A) having an SP value of 29.0 (MJ/m3) ^1/2 or more and 32.0 (MJ/m3) ^1/2 or less, when the total amount of the composition is 100% by weight. 0.0 wt% to 4.0 wt% of an active energy ray-curable compound (B) having an SP value of 18.0 (MJ/m3) ^1/2 or more and less than 21.0 (MJ/m3) ^1/2 5.0 wt% to 98.0 wt%, and , SP value contains 5.0 wt% to 98.0 wt% of an active energy ray-curable compound (C) of 21.0 (MJ/m 3 ) ^1/2 or more and 26.0 (MJ/m 3 ) ^1/2 or less.

In one embodiment, the reflectance of the antireflection layer is 1.5% or less.

In one embodiment, Re (550) of the retardation layer is 100 nm to 200 nm, and the angle between the slow axis of the retardation layer and the absorption axis of the polarizer is 40° to 50° or 130 ° to 140 °.

In one embodiment, the said retardation layer is comprised from the stretched film of a resin film, Re(450)/Re(550) is 0.80-1.03. Here, Re(450) and Re(550) are in-plane retardation measured with the light of wavelength 450nm and 550nm at 23 degreeC, respectively.

According to another aspect of the present invention, an image display apparatus is provided. This image display apparatus is equipped with said circularly-polarizing plate with an antireflection layer on the visual recognition side. The circularly polarizing plate with an antireflection layer is arrange|positioned so that the said antireflection layer may become a visual recognition side. The reflectance of the image display device is 40% or less.

In one embodiment, the said image display apparatus is an organic electroluminescent display apparatus.

According to an embodiment of the present invention, in a circularly polarizing plate, an antireflection layer is provided on the side that becomes the viewing side when applied to an image display device, and the protective layer and/or retardation layer of the polarizer and the antireflection layer is formed with a predetermined adhesive. By bonding together, the transmittance|permeability is high and it is excellent in durability in a high-temperature, high-humidity environment, As a result, the circularly polarizing plate with an antireflection layer which can implement|achieve the image display apparatus with which display unevenness was suppressed in a bright, high-temperature, high-humidity environment can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing of the circularly-polarizing plate with an antireflection layer which concerns on one Embodiment of this invention.

EMBODIMENT OF THE INVENTION Hereinafter, although typical embodiment of this invention is described, this invention is not limited to these embodiment.

(Definition of terms and symbols)

Definitions of terms and symbols in the present specification are as follows.

(1) refractive index (nx, ny, nz)

'nx' is the refractive index in the direction in which the in-plane refractive index is maximized (ie, the slow axis direction), and 'ny' is the refractive index in the direction orthogonal to the slow axis in the plane (ie, the fast axis direction). , 'nz' is the refractive index in the thickness direction.

(2) In-plane phase difference (Re)

'Re(λ)' is the in-plane retardation of the film measured with light having a wavelength of λ nm at 23°C. For example, 'Re(450)' is the in-plane retardation of the film measured with light having a wavelength of 450 nm at 23°C. Re(λ) can be calculated by the formula: Re=(nx-ny)×d when the thickness of the film is d (nm).

(3) retardation in thickness direction (Rth)

'Rth(λ)' is the retardation in the thickness direction of the film measured with light having a wavelength of λ nm at 23°C. For example, 'Rth (450)' is the retardation in the thickness direction of the film measured with light having a wavelength of 450 nm at 23°C. Rth(λ) can be obtained by the formula: Rth=(nx-nz)×d when the thickness of the film is d (nm).

(4) Nz coefficient

The Nz coefficient can be calculated|required by Nz=Rth/Re.

(5) angle

When referring to an angle in the present specification, unless otherwise specified, the angle includes angles in both clockwise and counterclockwise directions.

A. Overall configuration of circular polarizing plate with anti-reflection layer

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing of the circularly-polarizing plate with an antireflection layer which concerns on one Embodiment of this invention. A circularly polarizing plate 100 with an antireflection layer of the illustrated example includes a polarizing plate 10 and a reflection disposed on one side of the polarizing plate 10 (eg, on the opposite side to the image display cell when applied to an image display device, that is, the viewer side). It has the prevention layer 30 and the retardation layer 40 arrange|positioned on the other side of the polarizing plate 10 (for example, the image display cell side when applied to an image display apparatus). The polarizing plate 10 includes a polarizer 11 and a first protective layer 12 disposed on one side (antireflection layer side) of the polarizer 11 . Depending on the purpose, a second protective layer (not shown) may be provided on the retardation layer 40 side of the polarizer 11 . In addition, the protective layers on both sides of a polarizer may be abbreviate|omitted. For example, although the antireflection layer is typically formed on a substrate as described later, a laminate of the substrate/antireflection layer functions as a protective layer in some cases. In this case, the first protective layer 12 may be omitted. The laminate of the base material/antireflection layer may further include a hard coat layer. Accordingly, in the polarizing plate with a reflective layer, the protective layers on both sides are omitted, and the polarizer 11 , the antireflection layer 30 arranged on one side of the polarizer 11 , and the retardation arranged on the other side of the polarizer 11 . A configuration having the layer 40 may be used. Practically, any suitable pressure-sensitive adhesive layer 50 is provided as the outermost layer on the side opposite to the polarizing plate 10 of the retardation layer 40, and the circularly polarizing plate with an antireflection layer can be affixed to the image display cell.

In embodiment of this invention, the transmittance|permeability of a circularly-polarizing plate with an antireflection layer is 45.5 % or more, Preferably it is 46.0 % or more. The upper limit of the transmittance may be, for example, 46.5%. If the transmittance is within such a range, an image display device having a sufficiently high luminance can be realized. By providing the antireflection layer 30 , a high transmittance that is difficult to achieve with a circularly polarizing plate alone can be realized. In the embodiment of the present invention, further, the circularly polarizing plate with an antireflection layer has a reflectance of 2.5% or less, preferably 2.2% or less, and more preferably 2.0% after a heat and humidification test at 60°C and 90%RH for 500 hours. % or less. The lower limit of the reflectance may be, for example, 1.0%. By controlling the reflectance after the heating and humidification test to a predetermined value or less, when a circularly polarizing plate with an antireflection layer is applied to an image display device, it is possible to suppress display unevenness (particularly, stripe unevenness) in a high-temperature, high-humidity environment.

The retardation layer 40 is typically comprised by the stretched film of a resin film. Re (550) of the retardation layer 40 is typically 100 nm to 200 nm. Re(450)/Re(550) of the retardation layer is preferably 0.85 to 1.03. The angle between the slow axis of the retardation layer and the absorption axis of the polarizer 11 is preferably 40° to 50°, more preferably 42° to 48°, still more preferably 44° to 46°, particularly preferably about 45°; Alternatively, it is preferably 130° to 140°, more preferably 132° to 138°, still more preferably 134° to 136°, and particularly preferably about 135°.

The polarizer 11 and the protective layer 12 on the side of the antireflection layer 30 (a base material which forms an antireflection layer may be sufficient) are bonded together through the 1st adhesive bond layer 21 typically. In addition, the polarizer 11 and the retardation layer 40 are bonded together through the 2nd adhesive bond layer 22 typically. At least one of the adhesive agent of the 1st adhesive bond layer 21 and the 2nd adhesive bond layer 22 is comprised typically from the active energy ray hardening-type adhesive agent composition. The active energy ray-curable adhesive composition is an active energy ray-curable compound (A) having an SP value of 29.0 (MJ/m3) ^1/2 or more and 32.0 (MJ/m3) ^1/2 or less when the total amount of the composition is 100% by weight. 5.0 wt% to 98.0 wt% of an active energy ray-curable compound (B) having an SP value of 0.0 wt% to 4.0 wt%, 18.0 (MJ/m3) ^1/2 or more and less than 21.0 (MJ/m3) ^1/2 , and, The SP value contains 5.0 weight% - 98.0 weight% of active energy ray-curable compound (C) which are 21.0 (MJ/m<3>) ^1/2 or more and 26.0 (MJ/m<3>) ^1/2 or less. With such a configuration, a circularly polarizing plate with an antireflection layer having excellent durability in a high-temperature, high-humidity environment (for example, having a reflectance after the heating and humidification test as described above) is obtained, and as a result, an image display device in which display unevenness is suppressed in a high-temperature, high-humidity environment can be realized Preferably, at least the first adhesive layer 21 is composed of the active energy ray-curable adhesive composition, more preferably, both the first adhesive layer 21 and the second adhesive layer 22 are It is comprised from an active energy ray-curable adhesive composition. When the adhesive as described above is used, the durability of the polarizing plate under high temperature and high humidity is improved (display unevenness is suppressed), while there is a problem that the luminance (brightness) is insufficient when such a polarizing plate is applied to an image display device, the present invention According to embodiment, the circularly polarizing plate with an antireflection layer which can implement|achieve the image display apparatus with which display nonuniformity was suppressed in bright, high-temperature, high-humidity environment can be obtained.

In one embodiment, the circularly polarizing plate with an antireflection layer may further have another retardation layer (not shown) between the retardation layer 40 and the adhesive layer 50. FIG. The other retardation layer typically exhibits a relationship of refractive index characteristics of nz>nx=ny. By providing such another phase difference layer, reflection in an oblique direction can be prevented favorably, and wide viewing angle-ization of a reflection prevention function becomes possible.

In one embodiment, the circularly polarizing plate with an antireflection layer may further have a conductive layer or an isotropic base material with a conductive layer (not shown). When a conductive layer or an isotropic substrate with a conductive layer is provided, the circularly polarizing plate with an antireflection layer has a built-in touch sensor between the image display cell (eg, organic EL cell) and the polarizing plate, so-called inner touch panel type input display device can be applied to A conductive layer or an isotropic substrate with a conductive layer is typically provided between the retardation layer 40 and the pressure-sensitive adhesive layer 50 . When another phase difference layer is provided, another phase difference layer and a conductive layer or an isotropic base material with a conductive layer are typically provided in this order from the phase difference layer 40 side.

The circularly polarizing plate with an antireflection layer may have another retardation layer (not shown). Another retardation layer may be provided in combination with another retardation layer, and may be provided independently (that is, without providing another retardation layer). The optical characteristics (eg, refractive index characteristics, in-plane retardation, Nz coefficient, photoelastic coefficient), thickness, arrangement position, and the like of the other retardation layer may be appropriately set according to the purpose.

The circularly polarizing plate with an antireflection layer may have a sheet shape or a long picture shape may be sufficient as it. As used herein, "long shape" means an elongate shape having a sufficiently long length with respect to the width, and includes, for example, an elongated shape having a length of 10 times or more, preferably 20 times or more with respect to the width. A circularly polarizing plate with an elongate antireflection layer can be wound in roll shape.

Practically, it is preferable that the peeling film is temporarily attached to the surface of the adhesive layer 50 until the circularly-polarizing plate with an antireflection layer is provided for use. By temporarily adhering a peeling film, while protecting an adhesive layer, roll formation of a circularly-polarizing plate with an antireflection layer is attained.

Hereinafter, the components of a circularly polarizing plate with an antireflection layer are demonstrated.

B. Polarizer

As the polarizer 11, any suitable polarizer may be employed. For example, a single-layered resin film may be sufficient as the resin film which forms a polarizer, and the laminated body of two or more layers may be sufficient as it.

Specific examples of the polarizer composed of a single-layer resin film include polyvinyl alcohol (PVA)-based films, partially formalized PVA-based films, and hydrophilic polymer films such as ethylene/vinyl acetate copolymer-based partially saponified films, iodine, dichroic dyes, etc. polyene-based oriented films such as those subjected to a dyeing treatment and stretching treatment with a dichroic substance of PVA, dehydration treatment products of PVA, and dehydrochloric acid treatment products of polyvinyl chloride. Preferably, a polarizer obtained by dyeing a PVA-based film with iodine and uniaxially stretching from the viewpoint of excellent optical properties is used.

The dyeing with iodine is performed, for example, by immersing a PVA-based film in an aqueous iodine solution. The draw ratio of the said uniaxial stretching becomes like this. Preferably it is 3 to 7 times. Extending|stretching may be performed after a dyeing process, and may be performed, dyeing|staining. Moreover, you may dye|dye after extending|stretching. A swelling process, a crosslinking process, a washing process, a drying process, etc. are given to a PVA-type film as needed. For example, by immersing the PVA-based film in water and washing with water before dyeing, it is possible not only to wash the surface of the PVA-based film from stains and anti-blocking agents, but also to swell the PVA-based film to prevent staining of dyeing and the like.

As a specific example of the polarizer obtained using a laminated body, a laminated body of a resin substrate and the PVA system resin layer (PVA system resin film) laminated|stacked on the said resin substrate, or a resin substrate and the PVA system resin layer coated and formed on the said resin substrate. The light polarizer obtained using the laminated body of this is mentioned. A polarizer obtained by using a laminate of a resin substrate and a PVA-based resin layer applied and formed on the resin substrate is, for example, a PVA-based resin solution applied to a resin substrate, dried to form a PVA-based resin layer on the resin substrate, obtaining a laminate of a resin substrate and a PVA-based resin layer; stretching and dyeing the laminate to use the PVA-based resin layer as a polarizer; In this embodiment, extending|stretching includes extending|stretching by immersing a laminated body in boric-acid aqueous solution typically. In addition, stretching may further include, if necessary, aerial stretching of the laminate at a high temperature (eg, 95°C or higher) before stretching in an aqueous boric acid solution. The obtained laminated body of resin substrate / polarizer may be used as it is (that is, the resin substrate may be used as a protective layer of polarizer), and the resin substrate is peeled from the laminate of resin substrate / polarizer, and the said peeling surface is used for the purpose. Any suitable protective layer may be laminated and used. The detail of the manufacturing method of such a polarizer is described in Unexamined-Japanese-Patent No. 2012-73580, Unexamined-Japanese-Patent No. 6470455, for example. The description of these patent documents is incorporated herein by reference.

The polarizer may be preferably composed of a single-layered resin film. With such a structure, the circularly polarizing plate with the antireflection layer in which the phase difference nonuniformity in a high temperature environment was suppressed can be obtained by the synergistic effect with the optimization of a 1st adhesive layer and a 2nd adhesive layer.

The thickness of the polarizer is preferably about 1 µm to 30 µm, and more preferably about 5 µm to 25 µm. In particular, in order to obtain a polarizer having a thickness of 10 μm or less, as the polyvinyl alcohol-based film disclosed in Japanese Patent Application Laid-Open Nos. 2012-73580 and 6470455, etc., a polyvinyl alcohol-based film formed on a thermoplastic resin substrate. A manufacturing method of a thin polarizer using a laminate comprising a can be applied. If the thickness of a polarizer is such a range, the curl at the time of a heating can be suppressed favorably, and favorable external appearance durability at the time of a heating can be acquired.

The polarizer preferably exhibits absorption dichroism at any wavelength of 380 nm to 780 nm. The single transmittance of the polarizer is, for example, 41.5% to 46.0%, preferably 43.0% to 46.0%, and more preferably 44.5% to 46.0%. The single transmittance of the polarizer may be, for example, 44.0% or more, and may be, for example, 44.2% or more, or may be, for example, 44.6% or more. The polarization degree of a polarizer becomes like this. Preferably it is 97.0 % or more, More preferably, it is 99.0 % or more, More preferably, it is 99.9 % or more.

C. protective layer

The 1st protective layer 12 and the 2nd protective layer 13 are respectively formed from arbitrary suitable films which can be used as a protective layer of a polarizer. Specific examples of the material used as the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyester, polyvinyl alcohol, polycarbonate, polyamide, polyimide, polyethersulfone, and transparent resins such as polysulfone-based, polystyrene-based, polynorbornene-based, polyolefin-based, (meth)acrylic-based and acetate-based resins. Moreover, thermosetting resins, such as (meth)acrylic type, a urethane type, a (meth)acrylic urethane type, an epoxy type, a silicone type, or ultraviolet curable resin, etc. are mentioned. In addition, for example, glassy polymers, such as a siloxane type polymer, are mentioned. Moreover, the polymer film described in Unexamined-Japanese-Patent No. 2001-343529 (WO 01/37007) can also be used. As a material of this film, for example, a resin composition containing a thermoplastic resin having a substituted or unsubstituted imide group in a side chain and a thermoplastic resin having a substituted or unsubstituted phenyl group and a nitrile group in the side chain can be used, for example, isobutene and and a resin composition comprising an alternating copolymer composed of N-methylmaleimide and an acrylonitrile/styrene copolymer. The polymer film may be, for example, an extrusion molding of the resin composition.

The circularly polarizing plate with an antireflection layer is typically arrange|positioned on the visual recognition side of an image display apparatus so that it may mention later, and the 1st protective layer 12 is typically arrange|positioned on the visual recognition side. Accordingly, the first protective layer 12 may be subjected to a surface treatment such as a hard coat treatment, an antireflection treatment, an antistick treatment, and an antiglare treatment, if necessary. Further, to the first protective layer 12, if necessary, a process for improving visibility when visually viewed through polarized sunglasses (typically, imparting a (other) circular polarization function, and applying a super high phase difference ) may be performed. By performing such a process, even when a display screen is visually recognized through polarizing lenses, such as polarized sunglasses, the outstanding visibility can be implement|achieved. Therefore, the circularly polarizing plate with an antireflection layer can be suitably applied also to the image display apparatus which can be used outdoors.

The thickness of the first protective layer is typically 300 µm or less, preferably 100 µm or less, more preferably 5 µm to 80 µm, still more preferably 10 µm to 60 µm. In addition, when the surface treatment is performed, the thickness of the outer side protective layer is the thickness including the thickness of the surface treatment layer.

In one embodiment, the second protective layer 13 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 retardation Rth(550) in the thickness direction is -10 nm to +10 nm.

D. Retardation layer

As described above, the in-plane retardation Re(550) of the retardation layer is typically 100 nm to 200 nm, preferably 110 nm to 180 nm, more preferably 120 nm to 160 nm, further preferably 130 nm to 150 nm. That is, the retardation layer can function as a so-called λ/4 plate.

The retardation layer may exhibit wavelength dependence of inverse dispersion in which the retardation value increases with the wavelength of the measurement light, or may exhibit a flat wavelength dependence in which the retardation value is substantially constant regardless of the wavelength of the measurement light. When the phase difference value shows the wavelength dependence of the inverse dispersion, Re(450)/Re(550) is preferably 0.80 to 0.97, more preferably 0.85 to 0.95. When a phase difference value shows flat wavelength dependence, Re(450)/Re(550) becomes like this. Preferably it is 0.97-1.03, More preferably, it is 0.98-1.02.

Since the retardation layer has an in-plane retardation as described above, it has a relationship of nx>ny. The retardation layer exhibits any appropriate refractive index characteristic as long as it has a relationship of nx>ny. The refractive index characteristic of the retardation layer typically shows a relationship of nx>ny≥nz. In addition, 'ny=nz' includes not only the case where ny and nz are completely the same, but also the case where 'ny=nz' is substantially the same. Therefore, there may be a case where ny<nz is within a range that does not impair the effects of the present invention. Nz coefficient of retardation layer becomes like this. Preferably it is 0.9-2.0, More preferably, it is 0.9-1.5, More preferably, it is 0.9-1.2. By satisfying such a relationship, when a circularly polarizing plate with an antireflection layer is used for an image display apparatus, a very excellent reflection color can be achieved.

The thickness of the retardation layer can be set so that it can function most appropriately as a λ/4 plate. In other words, the thickness can be set so that a desired in-plane retardation is obtained. Specifically, the thickness is preferably 70 µm or less, and preferably 45 µm to 60 µm. Curl|Karl at the time of bonding can be adjusted favorably, suppressing the curl at the time of a heating favorably that the thickness of a phase difference layer is such a range.

The retardation layer has an absolute value of the photoelastic coefficient of preferably 20×10 ^-12 (m 2 /N) or less, more preferably 1.0×10 ^-12 (m 2 /N) to 15×10 ^-12 (m 2 /N). ), and more preferably 2.0×10 ^-12 (m 2 /N) to 12×10 ^-12 (m 2 /N). When the absolute value of a photoelastic coefficient is such a range, when a circularly-polarizing plate with an antireflection layer is applied to an image display apparatus, display nonuniformity can be suppressed.

The retardation layer may be composed of any suitable resin film capable of satisfying the above characteristics. Representative examples of such resins include polycarbonate resins, polyester carbonate resins, polyester resins, polyvinyl acetal resins, polyarylate resins, cyclic olefin resins, cellulose resins, polyvinyl alcohol resins, and polyamide-based resins, polyimide-based resins, polyether-based resins, polystyrene-based resins, and acrylic resins. These resins may be used individually or may be used in combination (for example, blending, copolymerization). The retardation layer, typically, may be composed of a polycarbonate-based resin or a polyester carbonate-based resin (hereinafter, simply referred to as a polycarbonate-based resin).

As said polycarbonate-type resin, arbitrary appropriate polycarbonate-type resin can be used. In one embodiment, the polycarbonate-based resin includes a structural unit derived from a fluorene-based dihydroxy compound, a structural unit derived from an isosorbide-based dihydroxy compound, an alicyclic diol, an alicyclic dimethanol, di, tri or polyethylene glycol, and a structural unit derived from at least one dihydroxy compound selected from the group consisting of alkylene glycol or spiro glycol. Preferably, the polycarbonate-based resin includes a structural unit derived from a fluorene-based dihydroxy compound, a structural unit derived from an isosorbide-based dihydroxy compound, a structural unit derived from an alicyclic dimethanol, and / or a structural unit derived from di, tri or polyethylene glycol; More preferably, it contains a structural unit derived from a fluorene-based dihydroxy compound, a structural unit derived from an isosorbide-based dihydroxy compound, and a structural unit derived from di, tri, or polyethylene glycol. . Polycarbonate-type resin may contain the structural unit derived from another dihydroxy compound as needed. Details of such polycarbonate-based resins are, for example, Japanese Patent Application Laid-Open No. 2014-10291, Japanese Unexamined Patent Publication No. 2014-26266, Japanese Unexamined Patent Publication No. 2015-212816, and Japanese Patent Application Laid-Open No. 2015-212817 No., Japanese Unexamined Patent Publication No. 2015-212818, the disclosure of which is incorporated herein by reference.

In another embodiment, polycarbonate-type resin contains the structural unit derived from the dihydroxy compound which has a bonding structure represented by following formula (I).

[Formula 1]

As a dihydroxy compound, the compound represented by following formula (II) is mentioned, for example. Examples of such a dihydroxy compound include isosorbide, isomannide, and isoidet, which have a stereoisomer relationship. These may be used independently and may be used in combination of 2 or more type.

[Formula 2]

You may use combining the said dihydroxy compound and another dihydroxy compound. As another dihydroxy compound, the alicyclic dihydroxy compound represented by following formula (III) is mentioned, for example.

HOCH ₂ -R ¹ -CH ₂ OH...(III)

In formula (III), R< ¹ > represents a C4-C20 cycloalkylene group. The alicyclic dihydroxy compound may be, for example, tricyclodecanedimethanol or pentacyclopentadecanedimethanol. These include various isomers in which R ¹ in the formula (III) is represented by the following formula (IV) (wherein n represents 0 or 1).

[Formula 3]

In one embodiment, polycarbonate-type resin contains the structural unit represented by following formula (V). That is, the polycarbonate-based resin may be a copolymer of diphenyl carbonate, isosorbide, and tricyclodecane dimethanol.

[Formula 4]

The detail of such polycarbonate-type resin is described in Unexamined-Japanese-Patent No. 2012-031370, for example, and description of this publication is taken in here as a reference.

It is preferable that the glass transition temperature of polycarbonate-type resin is 110 degreeC or more and 250 degrees C or less, More preferably, they are 120 degreeC or more and 230 degrees C or less. When the glass transition temperature is excessively low, heat resistance tends to deteriorate, and there is a possibility of causing a dimensional change after film forming. When the glass transition temperature is excessively high, the molding stability at the time of film forming may deteriorate, and the transparency of the film may be impaired. In addition, a glass transition temperature can be calculated|required according to JISK7121 (1987).

The molecular weight of polycarbonate-type resin can be represented by reduced viscosity. The reduced viscosity is measured by using methylene chloride as a solvent, precisely adjusting the polycarbonate concentration to 0.6 g/dL, and using an Uberode viscosity tube at a temperature of 20.0°C ±0.1°C. As for the lower limit of a reduced viscosity, 0.30 dL/g is preferable normally, More preferably, it is 0.35 dL/g or more. As for the upper limit of reduced viscosity, 1.20 dL/g is preferable normally, More preferably, it is 1.00 dL/g, More preferably, it is 0.80 dL/g. When a reduced viscosity is smaller than the said lower limit, the problem that the mechanical strength of a molded article becomes small may arise. On the other hand, when a reduced viscosity is larger than the said upper limit, the fluidity|liquidity at the time of shaping|molding may fall, and the problem that productivity and a moldability fall may arise.

You may use a commercially available film as a polycarbonate-type resin film. Specific examples of the commercially available products include “Pure Ace WR-S” manufactured by Teijin Corporation, “Pure Ace WR-W”, “Pure Ace WR-M” and “NRF” manufactured by Nitto Denko Corporation.

The retardation layer can be obtained by, for example, stretching a film formed of the polycarbonate-based resin. As a method for forming a film from a polycarbonate-based resin, any suitable molding processing method may be employed. Specific examples include a compression molding method, a transfer molding method, an injection molding method, an extrusion molding method, a blow molding method, a powder molding method, an FRP molding method, a cast coating method (eg, a casting method), a calender molding method, a hot press method, and the like. An extrusion molding method or a cast coating method is preferable. It is because the smoothness of the film obtained can be improved and favorable optical uniformity can be acquired. Molding conditions can be suitably set according to the composition and kind of resin used, characteristics desired for retardation layer, etc. In addition, as mentioned above, since many film products are marketed as for polycarbonate-type resin, you may use the said commercially available film for a extending|stretching process as it is.

The thickness of the resin film (unstretched film) can be set to any appropriate value according to the desired thickness of the retardation layer, desired optical properties, stretching conditions described later, and the like. Preferably it is 50 micrometers - 300 micrometers.

For the above stretching, any suitable stretching method and stretching conditions (eg, stretching temperature, stretching ratio, stretching direction) may be employed. Specifically, various stretching methods such as free-end stretching, fixed-end stretching, free-end contraction, and fixed-end contraction may be used alone, simultaneously or sequentially. The stretching direction can also be carried out in various directions and dimensions, such as the longitudinal direction, the width direction, the thickness direction, and the oblique direction. It is preferable that the temperature of extending|stretching is Tg-30 degreeC - Tg+60 degreeC with respect to the glass transition temperature (Tg) of a resin film, More preferably, they are Tg-10 degreeC - Tg+50 degreeC.

By appropriately selecting the stretching method and stretching conditions, a retardation film having the desired optical properties (eg, refractive index characteristic, in-plane retardation, Nz coefficient) can be obtained.

In one embodiment, the retardation film is produced by uniaxially stretching a resin film or uniaxially stretching a fixed end. As a specific example of fixed-end uniaxial stretching, the method of extending|stretching in the width direction (transverse direction) is mentioned, driving a resin film in a long longitudinal direction. A draw ratio becomes like this. Preferably it is 1.1 times - 3.5 times.

In another embodiment, the retardation film can be produced by continuously obliquely stretching a long resin film in the direction of the above angle θ with respect to the longitudinal direction. By employing oblique stretching, an elongated stretched film having an orientation angle of an angle θ (slow axis in the direction of angle θ) with respect to the longitudinal direction of the film is obtained, for example, at the time of lamination with a polarizing film. A roll-to-roll becomes possible, and a manufacturing process can be simplified. In addition, the angle θ may be an angle between the absorption axis of the polarizing film and the slow axis of the retardation layer in the polarizing plate with a retardation layer. As described above, the angle θ is preferably 40° to 50°, more preferably 42° to 48°, and still more preferably about 45°.

As a stretching machine used for diagonal stretching, for example, a tenter type stretching machine capable of applying a feeding force or a tensile force or a pulling force at different speeds in the transverse and/or longitudinal direction is mentioned. Although there exist a horizontal uniaxial stretching machine, a simultaneous biaxial stretching machine, etc. as a tenter type stretching machine, any suitable stretching machine can be used as long as it can diagonally stretch a long resin film continuously.

By appropriately controlling the left and right speeds in the stretching machine, a retardation layer (substantially, a long retardation film) having the desired in-plane retardation and having a slow axis in the desired direction can be obtained.

The stretching temperature of the film may vary depending on the in-plane retardation value and thickness desired for the retardation layer, the type of resin used, the thickness of the film used, the draw ratio, and the like. Specifically, the stretching temperature is preferably Tg-30°C to Tg+30°C, more preferably Tg-15°C to Tg+20°C, and most preferably Tg-10°C to Tg+15°C. By stretching at such a temperature, a retardation layer having suitable properties in the present invention can be obtained. In addition, Tg is the glass transition temperature of the constituent material of a film.

E. Anti-reflection layer

The antireflection layer 30 is typically a cured layer of an ionizing radiation curable resin composition. As described above, by providing the antireflection layer, a high transmittance that is difficult to achieve with a circularly polarizing plate alone can be realized. The reflectance of the antireflection layer is preferably 1.5% or less, more preferably 1.3% or less, and still more preferably 1.0% or less. The smaller the reflectance, the more preferable, and the lower limit thereof may be, for example, 0.2%. If the reflectance is within such a range, it is possible to prevent the reflection of external light and the like.

The ionizing radiation curable resin composition contains an ionizing radiation curable resin. The ionizing radiation curable resin composition may further contain a reactive diluent, a fluorine-containing additive, hollow particles, and/or solid particles according to the purpose.

Typical examples of the ionizing radiation curable resin include a thermosetting resin, an ultraviolet curable resin, a light (visible light) curable resin, and an electron beam curable resin. Examples of the ionizing radiation curable resin include a silicone resin, a polyester resin, a polyether resin, an epoxy resin, a urethane resin, an alkyd resin, a spiroacetal resin, a polybutadiene resin, and a polythiol polyene resin. Further, for example, the ionizing radiation curable resin may be a curable compound having an acrylate group and/or a methacrylate group that is cured by heat, light (such as ultraviolet rays) or electron beams. Specific examples include oligomers or prepolymers such as acrylates and/or methacrylates of polyfunctional compounds such as polyhydric alcohols. Ionizing radiation curable resin may be used independently and may be used in combination of 2 or more type.

The ionizing radiation curable resin may have a weight average molecular weight before curing, for example, 100 or more, 300 or more, 500 or more, 1000 or more, or 2000 or more, 100000 or less, 70000 or less, 50000 or less, 30000 or less, or 10000 or less. . When the weight average molecular weight before hardening is large, while hardness falls, there exists a tendency for a crack to become difficult to occur when it bends. When the weight average molecular weight before hardening is small, there exists a tendency for an intermolecular crosslinking density to improve and hardness to become high.

The reactive diluent typically contains an acrylate group and/or a methacrylate group. As a reactive diluent, the reactive diluent described in Unexamined-Japanese-Patent No. 2008-88309 can be used, for example. Specific examples of the reactive diluent include monofunctional acrylates, monofunctional methacrylates, polyfunctional acrylates and polyfunctional methacrylates. Preferably, they are trifunctional or more than trifunctional acrylate, and trifunctional or more than trifunctional methacrylate. Examples of the reactive diluent include butanediol glycerin ether diacrylate, acrylate of isocyanuric acid, methacrylate of isocyanuric acid, and the like. A reactive diluent may be used independently and may be used in combination of 2 or more type.

As the elemental fluorine-containing additive, any suitable compound can be used. The elemental fluorine-containing additive may be, for example, an organic compound or an inorganic compound containing fluorine in its molecule. Examples of the organic compound include a fluorine-containing antifouling coating agent, a fluorine-containing acrylic compound, and a fluorine/silicon-containing acrylic compound. As the organic compound, a commercially available product may be used. As a specific example, the brand name "KY-1203" manufactured by Shin-Etsu Chemical Industry Co., Ltd. and the brand name "Megapack" manufactured by DIC Corporation are mentioned. As the inorganic compound, any suitable fluorine-containing inorganic compound can be used.

The blending amount of the elemental fluorine additive may be, for example, 0.05 parts by weight or more, 0.1 parts by weight or more, 0.15 parts by weight or more, 0.20 parts by weight or more, or 0.25 parts by weight or more, and 20 parts by weight based on 100 parts by weight of the ionizing radiation curable resin. Parts by weight or less, 15 parts by weight or less, 10 parts by weight or less, 5 parts by weight or less, or 3 parts by weight or less may be sufficient.

As the hollow particles, any suitable hollow particles may be used. As a specific example, a silica particle, an acryl particle, and acryl- styrene copolymer particle|grains are mentioned. The hollow particle may use a commercial item. As a specific example of the commercial item of a silica particle, the Nikki Shokubai Chemicals Co., Ltd. product brand name "Sururia 5320", and "Sururia 4320" are mentioned. The weight average particle diameter of the hollow particles may be, for example, 30 nm or more, 40 nm or more, 50 nm or more, 60 nm or more, or 70 nm or more, 150 nm or less, 140 nm or less, 130 nm or less, 120 nm or less; Or 110 nm or less may be sufficient. As the shape of the hollow particles, any suitable shape can be adopted. The shape of the hollow particles may be, for example, a substantially spherical shape of a bead or an amorphous one such as a powder. Preferably it is substantially spherical, More preferably, it is substantially spherical with an aspect-ratio 1.5 or less, More preferably, it is substantially spherical shape. By blending the hollow particles, an antireflection layer having a low refractive index and good antireflection properties can be obtained. The blending amount of the hollow particles may be, for example, 30 parts by weight or more, 50 parts by weight or more, 70 parts by weight or more, 90 parts by weight or more, or 100 parts by weight or more, and 300 parts by weight or less with respect to 100 parts by weight of the ionizing radiation curable resin. , 270 parts by weight or less, 250 parts by weight or less, 200 parts by weight or less, or 180 parts by weight or less may be sufficient. When the blending amount is within such a range, an antireflection layer having excellent mechanical properties and a low refractive index can be obtained.

As the solid particles, any suitable solid particles may be used. As a specific example, a silica particle, a zirconium oxide particle, and a titanium particle are mentioned. A commercial item may be used for solid particle|grains. As a specific example of the commercial item of a silica particle, the Nissan Chemical Industry Co., Ltd. brand names 'MEK-2140Z-AC', 'MIBK-ST', and 'IPA-ST' are mentioned. The weight average particle diameter of the solid particles may be, for example, 5 nm or more, 10 nm or more, 15 nm or more, 20 nm or more, or 25 nm or more, 3300 nm or less, 250 nm or less, 200 nm or less, 150 nm or less; Or 100 nm or less may be sufficient. As the shape of the solid particles, any suitable shape can be adopted. The shape of the solid particles may be, for example, a substantially spherical shape of a bead or an amorphous one such as a powder. Preferably it is substantially spherical, More preferably, it is substantially spherical with an aspect-ratio 1.5 or less, More preferably, it is substantially spherical shape. By blending the solid particles, the elemental fluorine-containing additive tends to be unevenly distributed on the surface of the antireflection layer, and as a result, an antireflection layer having a low refractive index and good antireflection properties can be obtained. The blending amount of the solid particles may be, for example, 5 parts by weight or more, 10 parts by weight or more, 15 parts by weight or more, 20 parts by weight or more, or 25 parts by weight or more, and 150 parts by weight or less with respect to 100 parts by weight of the ionizing radiation curable resin. , 120 parts by weight or less, 100 parts by weight or less, or 80 parts by weight or less may be sufficient. If the blending amount is within such a range, an antireflection layer excellent in the balance of mechanical properties, refractive index, and transparency can be obtained.

The antireflection layer can typically be formed by the following manufacturing method: A coating solution for forming an antireflection layer obtained by diluting an ionizing radiation curable resin composition with a diluting solvent is applied; dry the coating; And, the dried coating film is cured.

As the diluting solvent, any suitable solvent may be used depending on the ionizing radiation curable resin. Examples of the diluting solvent include alcohols such as methanol, ethanol, isopropyl alcohol, butanol, TBA (tertiary butyl alcohol) and 2-methoxyethanol; ketones such as acetone, methyl ethyl ketone, MIBK (methyl isobutyl ketone), and cyclopentanone; esters such as methyl acetate, ethyl acetate, butyl acetate, and PMA (propylene glycol monomethyl ether acetate); ethers such as diisopropyl ether and propylene glycol monomethyl ether; glycols such as ethylene glycol and propylene glycol; cellosolves such as ethyl cellosolve and butyl cellosolve; aliphatic hydrocarbons such as hexane, heptane and octane; and aromatic hydrocarbons such as benzene, toluene and xylene. A dilution solvent may be used independently and may be used in combination of 2 or more type. The polarity can be adjusted by mixing a plurality of solvents in any suitable ratio according to the purpose.

The dilution solvent may be, for example, a mixed solvent including MIBK and PMA. The mixing ratio in this case may be appropriately set according to the purpose. The mixing ratio may be, for example, 20 parts by weight or more, 50 parts by weight or more, 100 parts by weight or more, 150 parts by weight or more, or 200 parts by weight or more, 400 parts by weight or less, 350 parts by weight with respect to 100 parts by weight of MIBK. A weight part or less, 300 weight part or less, or 250 weight part or less may be sufficient.

The dilution solvent may be, for example, a mixed solvent including TBA in addition to MIBK and PMA. The mixing ratio in this case may also be appropriately set according to the purpose. The mixing ratio may be, for example, 10 parts by weight or more, 30 parts by weight or more, 50 parts by weight or more, 80 parts by weight or more, or 100 parts by weight or more, 200 parts by weight or less, 180 parts by weight with respect to 100 parts by weight of MIBK. may be less than or equal to 150 parts by weight, less than or equal to 130 parts by weight, or less than or equal to 110 parts by weight; TBA may be, for example, 10 parts by weight or more, 30 parts by weight or more, 50 parts by weight or more, 80 parts by weight or more, or 100 parts by weight or more, 200 parts by weight or less, 180 parts by weight or less, 150 parts by weight or less, 130 parts by weight or less. part or less, or 110 weight part or less may be sufficient.

The solid content concentration of the coating solution may be, for example, 0.1% by weight or more, 0.3% by weight or more, 0.5% by weight or more, 1.0% by weight or more, or 1.5% by weight or more, 20% by weight or less, 15% by weight or less, You may make it 10 weight% or less, 5 weight% or less, or 3 weight% or less. When the solid content concentration is within such a range, it is possible to achieve both coatability (eg, wetting, leveling) and prevention of poor appearance of the coating film (eg, air drying stains, whitening).

A hardening|curing agent may be added to a coating liquid as needed. As the curing agent, any suitable polymerization initiator (eg, thermal polymerization initiator, photopolymerization initiator, etc.) can be used. The amount of the curing agent added may be, for example, 0.5 parts by weight or more, 1.0 parts by weight or more, 1.5 parts by weight or more, 2.0 parts by weight or more, or 2.5 parts by weight or more, 15 parts by weight or less, based on 100 parts by weight of the ionizing radiation curable resin; 13 parts by weight or less, 10 parts by weight or less, 7 parts by weight or less, or 5 parts by weight or less may be sufficient.

An antireflection layer is typically laminated|stacked on a polarizer or a polarizing plate via arbitrary suitable adhesive bond layers or adhesive layers, after being formed on arbitrary suitable base materials. First, a coating liquid is coated on a base material. As a coating method, any suitable method can be employ|adopted. Specific examples include a panten coating method, a die coating method, a spin coating method, a spray coating method, a gravure coating method, a roll coating method, and a bar coating method. The coating amount of the coating liquid can be appropriately set according to the thickness of the antireflection layer to be formed. The thickness of the antireflection layer to be formed may be, for example, 0.1 µm or more, 0.3 µm or more, 0.5 µm or more, 1.0 µm or more, or 2.0 µm or more, and 50 µm or less, 40 µm or less, 30 µm or less, 20 µm or less, or 10 micrometers or less may be sufficient.

Next, the coated coating liquid is dried to form a coating film. The drying temperature may be appropriately set according to the purpose. The drying temperature may be, for example, 30 °C or higher, 40 °C or higher, 50 °C or higher, 60 °C or higher, 70 °C or higher, 80 °C or higher, 90 °C or higher, or 100 °C or higher, 200 °C or lower, 190 °C or lower, 180 °C or higher. °C or lower, 170 °C or lower, 160 °C or lower, 150 °C or lower, 140 °C or lower, 135 °C or lower, 130 °C or lower, 120 °C or lower, or 110 °C or lower may be sufficient. The drying time may also be appropriately set according to the purpose. The drying time may be, for example, 30 seconds or more, 40 seconds or more, 50 seconds or more, or 60 seconds or more, and may be 150 seconds or less, 130 seconds or less, 110 seconds or less, or 90 seconds or less.

Next, the coating film is cured. Curing can be performed, for example, by heating, light irradiation, or the like. The light used for light irradiation may be, for example, ultraviolet light or visible light. The light source of the light irradiation may be, for example, a high-pressure mercury lamp. The irradiation amount of the energy ray source in ultraviolet curing is an accumulated exposure amount at an ultraviolet wavelength of 365 nm, and is 50 mJ/cm 2 to 500 mJ/cm 2 desirable. When an irradiation amount is 50 mJ/cm<2> or more, hardening will fully advance easily and the hardness of the antireflection layer formed will become high easily. When the irradiation amount is 500 mJ/cm 2 or less, it is possible to prevent discoloration of the formed antireflection layer.

F. First Adhesive Layer and Second Adhesive Layer

As mentioned above, at least one of the adhesive agent of the 1st adhesive bond layer 21 and the 2nd adhesive bond layer 22 is comprised typically from the active energy ray hardening-type adhesive agent composition. The active energy ray-curable adhesive composition is an active energy ray-curable compound (A) having an SP value of 29.0 (MJ/m3) ^1/2 or more and 32.0 (MJ/m3) ^1/2 or less when the total amount of the composition is 100% by weight. 5.0 wt% to 98.0 wt% of an active energy ray-curable compound (B) having an SP value of 0.0 wt% to 4.0 wt%, 18.0 (MJ/m3) ^1/2 or more and less than 21.0 (MJ/m3) ^1/2 , and, The SP value contains 5.0 weight% - 98.0 weight% of active energy ray-curable compound (C) whose SP value is 21.0 (MJ/m<3>) ^1/2 or more and 26.0 (MJ/m<3>) ^1/2 or less. Preferably, at least the first adhesive layer 21 is composed of the active energy ray-curable adhesive composition, more preferably, both the first adhesive layer 21 and the second adhesive layer 22 are It is comprised from an active-energy-ray-curable adhesive composition. Further, when only one side of the first adhesive layer 21 or the second adhesive layer 22 is composed of the active energy ray-curable adhesive composition, the other adhesive layer may be composed of any suitable adhesive.

Hereinafter, said active energy ray hardening-type adhesive composition is demonstrated.

Specific examples of the active energy ray-curable compound (A) include hydroxyethyl acrylamide (SP value 29.5) and N-methylolacrylamide (SP value 31.5). The content of the compound (A) is preferably 4.0% by weight or less, more preferably 2.0% by weight, still more preferably 1.5% by weight, particularly preferably 1.0 when the total amount of the composition is 100% by weight. % by weight. The composition preferably does not contain the compound (A).

Specific examples of the active energy ray-curable compound (B) include tripropylene glycol diacrylate (SP value 19.0), 1,9-nonanediol diacrylate (SP value 19.2), tricyclodecane dimethanol diacrylate (SP value) 20.3), cyclic trimethylolpropane formal acrylate (SP value 19.1), dioxane glycol diacrylate (SP value 19.4), and EO modified diglycerin tetraacrylate (SP value 20.9). You may use a commercial item as a compound (B). Specific examples of the commercial product include Aronix M-220 (manufactured by Dong-A Synthetic Co., Ltd., SP value 19.0), light acrylate 1,9ND-A (manufactured by Gongyeong Chemical Co., Ltd., SP value 19.2), light acrylate DGE-4A (manufactured by Gongyeong Chemical Co., Ltd.) , SP value 20.9), light acrylate DCP-A (manufactured by Gongyeong Chemical Co., Ltd., SP value 20.3), SR-531 (manufactured by SARTOMER, SP value 19.1), CD-536 (SARTOMER) Manufacture, SP value 19.4) is mentioned. When content of a compound (B) makes composition whole quantity 100 weight%, Preferably it is 20 weight% - 80 weight%, More preferably, it is 25 weight% - 70 weight%.

Specific examples of the active energy ray-curable compound (C) include acryloylmorpholine (SP value 22.9), N-methoxymethylacrylamide (SP value 22.9), and N-ethoxymethylacrylamide (SP value 22.3). can You may use a commercial item as a compound (C). As a specific example of a commercial item, ACMO (made by Heungin, SP value 22.9), Wasmer 2MA (made by Kasanokosan, SP value 22.9), Wasmer EMA (made by Kasanokosan, SP value 22.3), Wasmer 3MA (Kasanoko Corporation, SP value 22.3), Wasmer 3MA (Kasanoko) The acid company make, SP value 22.4) is mentioned. The content of the compound (C) is preferably 20 wt% to 80 wt%, more preferably 25 wt% to 70 wt%, when the total amount of the composition is 100 wt%.

SP value (solubility parameter) is calculated by Fedors' method (see "Polymer Eng. & Sci.", Vol. 14, No. 2 (1974), pages 148 to 154). can be saved

The active energy ray-curable adhesive composition may further contain the acryl-type oligomer (D) formed by superposing|polymerizing a (meth)acryl monomer. By containing the oligomer, the adhesion between the antireflection layer and the polarizing plate (substantially, the first protective layer) and/or the adhesion between the antireflection layer and the retardation layer can be increased. When content of an oligomer (D) makes the composition whole quantity 100 weight%, Preferably it is 3.0 weight% or more, More preferably, it is 5.0 weight% or more. On the other hand, content becomes like this. Preferably it is 25 weight% or less, More preferably, it is 15 weight% or less. In such a range, curing shrinkage (excessive curing) and poor curing (insufficient curing) can be suppressed. The weight average molecular weight (Mw) of an oligomer (D) becomes like this. Preferably it is 15000 or less, More preferably, it is 10000 or less, More preferably, it is 5000 or less. On the other hand, the weight average molecular weight (Mw) becomes like this. Preferably it is 500 or more, More preferably, it is 1000 or more, More preferably, it is 1500 or more.

The active energy ray-curable adhesive composition may further contain a radical polymerization initiator (E) having a hydrogen extraction action. As a radical polymerization initiator (E), a thioxanthone type radical polymerization initiator and a benzophenone type radical polymerization initiator are mentioned, for example. Diethylthioxanthone is preferred.

The thickness of the first adhesive layer and/or the second adhesive layer composed of the active energy ray-curable adhesive composition is preferably 0.01 μm to 3.0 μm, more preferably 0.1 μm to 2.5 μm, still more preferably 0.5 μm to 1.5 μm.

An easily adhesive layer may be provided between the polarizing plate and the first adhesive layer and/or the second adhesive layer.

The detail of the composition which forms said active energy ray hardening-type adhesive composition and an easily adhesive layer is described in Unexamined-Japanese-Patent No. 2019-147865, for example. The description of the said publication is taken in in this specification as a reference.

G. Image display device

The circularly polarizing plate with an antireflection layer according to the above items A to F can be applied to an image display device. Accordingly, the embodiment of the present invention also includes an image display device using such a circularly polarizing plate with an antireflection layer. An image display device according to an embodiment of the present invention is typically provided with the circularly polarizing plate with an antireflection layer according to the items A to F above on the visual recognition side thereof. The circularly polarizing plate with an antireflection layer is arrange|positioned so that the said antireflection layer may become a visual recognition side. The reflectance of the image display device is preferably 40% or less. In the image display device having such a reflectance, the effect of the circularly polarizing plate with an antireflection layer as described in the said A to F items becomes a remarkable thing. Specifically, it is as follows. When the reflectance of the image display device is low, while the reflection of the displayed image and the like can be made small, the display unevenness (eg, streaks) is also difficult to be visually recognized by the image display device under a high temperature, high humidity environment. A liquid crystal display device and an organic electroluminescent (EL) display device are mentioned as a representative example of an image display apparatus. Preferably, it is an organic electroluminescence display.

[Example]

Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples. In addition, the measuring method of each characteristic is as follows.

(1) transmittance

The transmittance|permeability of the circularly-polarizing plate with an antireflection layer obtained by the Example and the comparative example was measured using the ultraviolet/visible light spectrophotometer (V-7100 made by Nippon Bunko Corporation). In addition, the single transmittance|permeability is the Y value which measured with the 2 degree field of view (C light source) of JISZ8701, and performed the visibility correction|amendment.

(2) reflectance

The circularly polarizing plate with an antireflection layer obtained in the Example and the comparative example was cut out to a predetermined size, and the surface of the phase difference layer was corona-treated. The corona-treated surface of the circularly polarizing plate with an antireflection layer was bonded to an alkali-free glass plate through an acrylic adhesive (20 µm) to prepare a laminate. This laminate was subjected to a heat and humidification test at 60°C and 90%RH for 500 hours. The laminated body after a heating and humidification test was mounted on the organic electroluminescent apparatus replacement product so that a glass plate surface might oppose, and it was set as the test sample. About this test sample, the front reflectance was measured using the spectrophotometer "CM-2600d" manufactured by Konica Minolta. Frontal reflectance was measured by the SCI method.

In addition, the organic electroluminescent display apparatus substitute was produced as follows. An aluminum vapor deposition film (manufactured by Toray Film Processing Co., Ltd., trade name 'DMS vapor deposition X-42', thickness 50 µm) was bonded to an acrylic plate with an adhesive, and this was used as a substitute for an organic EL display device.

(3) Display unevenness

About the test sample produced in the same manner as in (1) above, the display unevenness (streak, color unevenness, luminance unevenness, etc.) of the test sample was visually observed under a fluorescent lamp, and evaluated according to the following criteria.

(circle): Display nonuniformity is not recognized in any of the front direction and the oblique direction.

(triangle|delta): Display nonuniformity was not confirmed in the front direction, but display nonuniformity was confirmed in the oblique direction.

x: Display nonuniformity is recognized in both the front direction and the oblique direction

(4) luminance

The organic EL panel was taken out from the organic EL display (manufactured by Samsung, product name 'Galaxy S5'), the polarizing film affixed to the organic EL panel was peeled off, and instead the originals obtained in Examples and Comparative Examples The polarizing plate was bonded together to obtain an organic EL display device. A white image was displayed on the obtained organic EL display device, and the front luminance (cd) was measured using a spectroradiometer (trade name: 'SR-UL1R') manufactured by TOPCON.

[Production Example 1: Preparation of a polarizing plate]

(Manufacture of polarizer)

A 45-micrometer-thick polyvinyl alcohol film having an average degree of polymerization of 2400 and a degree of saponification of 99.9 mol% was immersed in hot water at 30°C for 60 seconds to swell. Then, the film was immersed in an aqueous solution having a concentration of 0.3% of iodine/potassium iodide (weight ratio = 1/7), and the film was dyed while stretching to 2.6 times. Then, it extended|stretched so that the total draw ratio might become 6 times in a 65 degreeC 4 weight% boric acid aqueous solution. After extending|stretching, it dried in 55 degreeC oven for 1 minute, and obtained the PVA system polarizer. The thickness of this polarizer was 18 micrometers, and the moisture content was 15 weight%.

(Production of polarizing plate)

On the surface (surface on the opposite side to the resin base material) of the obtained polarizer, a cycloolefin-based film (manufactured by Nippon Zeon, ZF-12, 23 µm) as a protective layer was bonded through an ultraviolet curable adhesive. Specifically, it coated so that the total thickness of a curable adhesive might be set to about 1.0 micrometer, and it bonded together using the roll machine. Thereafter, UV rays were irradiated from the cycloolefin-based film side to cure the adhesive. Next, the resin base material was peeled, and the polarizing plate which has the structure of a cycloolefin type film (protective layer)/polarizer was obtained.

[Production Example 2: Preparation of retardation film constituting retardation layer]

Polymerization was carried out using a batch polymerization apparatus comprising two vertical reactors equipped with stirring blades and a reflux condenser controlled at 100°C. Bis[9-(2-phenoxycarbonylethyl)fluoren-9-yl]methane 29.60 parts by mass (0.046 mol), isosorbide (ISB) 29.21 parts by mass (0.200 mol), spiroglycol (SPG) 42.28 mass Parts (0.139 mol), 63.77 parts by mass (0.298 mol) of diphenyl carbonate (DPC), and 1.19×10 ^-2 parts by mass (6.78×10 ^-5 mol) of calcium acetate monohydrate as a catalyst were added. After replacing the inside of the reactor with reduced pressure nitrogen, heating was performed with a heat medium, and stirring was started when the internal temperature reached 100°C. The internal temperature was made to reach 220 degreeC 40 minutes after the start of temperature rise, and while controlling so that this temperature might be maintained, pressure reduction was started, and it was 13.3 kPa in 90 minutes after reaching 220 degreeC. The phenol vapor produced by the polymerization reaction was guided to a reflux condenser at 100° C., the monomer component contained in a small amount in the phenol vapor was returned to the reactor, and the phenol vapor that was not condensed was recovered by inducing it to a condenser at 45° C. After nitrogen was introduced into the first reactor and the pressure was returned to atmospheric pressure, the oligomerized reaction solution in the first reactor was transferred to the second reactor. Then, the temperature rise and pressure reduction in the 2nd reactor were started, and it was set as the internal temperature of 240 degreeC and the pressure of 0.2 kPa in 50 minutes. Thereafter, polymerization was allowed to proceed until a predetermined stirring power was reached. At the time when a predetermined power was reached, nitrogen was introduced into the reactor and the pressure was restored, the resulting polyester carbonate-based resin was extruded into water, and the strands were cut to obtain pellets.

After vacuum drying the obtained polyester carbonate-based resin (pellet) at 80 ° C. for 5 hours, a single screw extruder (manufactured by Toshiba Machinery Co., Ltd., cylinder set temperature: 250 ° C), T-die (width 200 mm, set temperature: 250 ° C) , a 135-micrometer-thick long resin film was produced using the film film forming apparatus provided with , a chill roll (set temperature: 120-130 degreeC) and a winder. The obtained elongate resin film was extended|stretched by the extending|stretching temperature of 133 degreeC, and a draw ratio of 2.8 times in the width direction, and the 48-micrometer-thick retardation film I was obtained. Re(550) of the obtained retardation film was 141 nm, Re(450)/Re(550) was 0.82, and Nz coefficient was 1.12.

[Production Example 3: Preparation of retardation film constituting retardation layer]

To 81.98 parts by mass of isosorbide (hereinafter sometimes abbreviated as 'ISB'), 47.19 parts by mass of tricyclodecanedimethanol (hereinafter sometimes abbreviated as 'TCDDM'), diphenyl carbonate (hereinafter, 'DPC') 175.1 parts by mass, and 0.979 parts by mass of a 0.2 mass % cesium carbonate aqueous solution as a catalyst are put into a reaction vessel, and in a nitrogen atmosphere, as the first step of the reaction, the heating bath temperature is heated to 150 ° C. , while stirring as needed, the raw material was dissolved (about 15 minutes). Next, the generated phenol was taken out of the reaction vessel while the pressure was set to 13.3 kPa from normal pressure and the heating bath temperature was raised to 190°C in 1 hour. After holding the entire reaction vessel at 190°C for 15 minutes, as a second step, the pressure in the reaction vessel is set to 6.67 kPa, the heating bath temperature is raised to 230°C in 15 minutes, and the generated phenol is removed from the reaction vessel ejected outside. Since the stirring torque of the stirrer increased, the temperature was raised to 250°C in 8 minutes, and the pressure in the reaction vessel was set to 0.200 kPa or less in order to remove the phenol generated further. After reaching a predetermined stirring torque, the reaction was terminated, and the resulting reactant was extruded into water to obtain pellets of a polycarbonate copolymer.

After vacuum drying the obtained pellets at 80 ° C. for 5 hours, a single screw extruder (manufactured by Toshiba Machinery Co., Ltd., cylinder set temperature: 250 ° C), T-die (width 200 mm, set temperature: 250 ° C), chill roll (set temperature: 120-130 degreeC) and the film film forming apparatus provided with the winding machine was used, and the resin film was produced. The obtained elongate resin film was extended|stretched diagonally at the extending|stretching temperature of 140 degreeC, and the draw ratio of 2.2 times, and 30-micrometer-thick retardation film II was obtained. Re(550) of the obtained retardation film was 144 nm, Re(450)/Re(550) was 1.02, and the Nz coefficient was 1.2.

[Production Example 4: Preparation of anti-reflection layer]

[Production Example 4-1: Preparation of hard coat layer]

As a resin included in the hard coat layer, 100 parts by weight of an ultraviolet curable urethane acrylate resin (manufactured by DIC Co., Ltd., trade name 'Unidic 17-806', solid content 80%) was prepared. Per 100 parts by weight of the resin solid content of the resin, 3 parts by weight of a photopolymerization initiator (manufactured by BASF, trade name 'OMNIRAD907'), a leveling agent (manufactured by DIC Co., Ltd., trade name 'GRANDIC PC4100', solid content 10 %) was mixed in 0.01 parts by weight. This mixture was diluted with a butyl acetate/cyclopentanone mixed solvent (weight ratio 80/20) so that the solid content concentration was 40% to prepare a hard coat layer forming material (coating solution). On the surface of a substrate (a TAC film having a thickness of 60 µm), the coating solution was applied with a wire bar. The coated coating solution was heated at 80°C for 1 minute and dried to form a coating film. The coating film after drying was irradiated with an ultraviolet-ray of 300 mJ/cm<2> of accumulated light quantity with a high pressure mercury lamp, it hardened, and the hard coat film (hard-coat layer) was obtained on the base material.

[Production Example 4-2: Preparation of anti-reflection layer]

100 parts by weight of a polyfunctional acrylate containing pentaerythritol triacrylate as a main component (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name 'Viscoat #300', solid content 100% by weight), hollow nanosilica particles (manufactured by Nikki Catalyst Chemical Industry Co., Ltd.) , trade name 'Sururia 5320', solid content 20% by weight, weight average particle diameter 75nm) 100 parts by weight, solid nano-silica particles (manufactured by Nissan Chemical Industry Co., Ltd., trade name 'MEK-2140Z-AC', solid content 30% by weight, weight Average particle diameter of 10 nm) 40 parts by weight, elemental fluorine-containing additive (manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name 'KY-1203', solid content 20% by weight) 12 parts by weight, and a photopolymerization initiator (IGM Resins B.V. 3 parts by weight (manufactured by Company, trade name 'Omnirad 907', solid content 100% by weight) were mixed. To the mixture, a mixed solvent in which TBA (tertiary butyl alcohol), MIBK (methyl isobutyl ketone) and PMA (propylene glycol monomethyl ether acetate) were mixed in a weight ratio of 60:25:15 as a diluting solvent was added, and the total solid content It was made to become this 4 weight%, and it stirred, and prepared the coating liquid for antireflection layer formation.

On the surface of the hard coat layer of the laminate of the base material/hard coat layer obtained in Production Example 4-1, the coating solution for forming an antireflection layer obtained in Production Example 4-2 was coated with a wire bar. The coated coating solution was heated at 80°C for 1 minute and dried to form a coating film. The coating film after drying was cured by irradiating ultraviolet rays with an accumulated light amount of 300 mJ/cm 2 with a high-pressure mercury lamp to form an antireflection layer. In this way, the laminate of the base material/hard coat (HC) layer/reflection prevention layer was produced.

[Production Example 5: Preparation of the adhesive composition constituting the adhesive layer]

45 parts by mass of acryloylmorpholine (manufactured by Heungin, trade name 'ACMO', SP value: 22.9), 1,9-nonanediol diacrylate (trade name 'light acrylate 1,9ND-A', manufactured by Gongyeong Chemical Co., Ltd.) ) 41 parts by mass, 10 parts by mass of an acrylic oligomer obtained by polymerizing a (meth)acrylic monomer (trade name 'ARUFON UG4010', manufactured by Dong-A Synthesis Co., Ltd.), diethylthioxanthone as a photopolymerization initiator (trade name 'KAYACURE DETX-S', Nippon Kaya) 1.5 parts by mass (manufactured by Co., Ltd.) and 2.5 mass parts by mass of 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (trade name "IRGACURE907", manufactured by BASF) which is a photoinitiator The adhesive composition was prepared by mixing parts and stirring at 50 degreeC for 1 hour. For convenience, this adhesive composition is referred to as a high-durability adhesive composition.

[Production Example 6: Preparation of the adhesive composition constituting the adhesive layer]

As an adhesive, 12 parts by weight of hydroxyethylacrylamide (manufactured by Heungin, trade name 'HEAA', SP value: 29.5), acryloylmorpholine (manufactured by Heungin Corporation, trade name 'ACMO', SP value: 22.9) 35 parts by weight , 1,9-nonanediol diacrylate (trade name: 'Light acrylate 1,9ND-A', manufactured by Gongyeong Chemical) 40 parts by weight, acrylic oligomer (trade name: 'ARUFON UG4010', manufactured by Dong-A Synthesis) 10 parts by weight, photopolymerization As an initiator, 2 parts by weight of KAYACURE DETX-S ((2,4-diethylthioxanthone), manufactured by Nippon Kayaku Co., Ltd.) and a photosensitizer IRGACURE907 (2-methyl-1-(4-methylthiophenyl)-2- Morpholinopropan-1-one, trade name 'IRGACURE907', manufactured by BASF) was mixed in a ratio of 1 part by weight and stirred at 50°C for 1 hour to prepare an adhesive composition. For convenience, this adhesive composition is usually referred to as an adhesive composition.

[Production Example 7: Preparation of composition (easy-adhesive composition) constituting the easily-adhesive layer]

50 parts by mass of acryloylmorpholine (manufactured by Heungin Co., Ltd., trade name 'ACMO', SP value: 22.9) and 0.9 parts by mass of 3-acrylamidephenylboronic acid (manufactured by Sunjeong Chemical Co., Ltd.) were mixed, and the resulting mixture was stirred at 25°C for 30 minutes. An easily adhesive composition was prepared by stirring and mixing 48.3 mass parts of water and 0.8 mass parts of a leveling agent (the Nisshin Chemical Industry Co., Ltd. make, brand name "Olphin EXP.4123") to the mixture, and stirring at 25 degreeC for 10 minutes.

[Examples 1 to 4 and Comparative Examples 1 to 5]

A polarizing plate, a retardation film (retardation layer), an antireflection layer, and an adhesive agent (a first adhesive layer and a second adhesive layer) were combined as shown in Table 1, as shown in FIG. 1 (provided that the first and second protection No layer) A circularly polarizing plate with an antireflection layer was produced. The specific production method was as follows. The easily-adhesive composition of Preparation Example 7 was coated on both surfaces of a polarizer with the initially set thickness of 1100 nm. On the other hand, the 1st adhesive bond layer was formed on the base material surface of the laminated body obtained by manufacture example 4, and the antireflection layer was bonded to the polarizing plate (substantially, an easily adhesive layer) through the 1st adhesive bond layer. Similarly, a second adhesive layer was formed on one side of the retardation film constituting the retardation layer obtained in Production Example 3, and the retardation film was bonded to a polarizing plate (substantially, an easily adhesive layer) through the second adhesive layer. Next, visible light was irradiated with an active energy ray irradiation device, the first and second adhesive layers were cured, and further, hot air dried at 70° C. for 3 minutes to prepare a circularly polarizing plate with an antireflection layer. Moreover, the acrylic adhesive layer (23 micrometers) was provided on the retardation layer surface (opposite side to a polarizer) of a circularly-polarizing plate with an antireflection layer. Here, the polarizing plate and the retardation layer (retardation film) were bonded together so that the absorption axis of a polarizer and the slow axis of retardation film made an angle of 45 degrees. The obtained circularly polarizing plate with an antireflection layer was used for evaluation of said (1)-(4). A result is shown in Table 1.

[Table 1]

[evaluation]

As is clear from Table 1, according to the circularly polarizing plate with an antireflection layer of the Example of this invention, it turns out that the image display apparatus with which display nonuniformity was suppressed in a bright, high temperature, high humidity environment can be implement|achieved.

[Industrial Applicability]

The circularly polarizing plate with an antireflection layer of this invention can be used suitably for an image display device (representatively, a liquid crystal display device, an organic electroluminescent display device).

10: polarizer
11: Polarizer
12: first protective layer
21: first adhesive layer
22: second adhesive layer
30: anti-reflection layer
40: retardation layer
100: circularly polarizing plate with anti-reflection layer

Claims (7)

A polarizing plate including a polarizer, an antireflection layer disposed on one side of the polarizing plate, and a retardation layer disposed on the other side of the polarizing plate,
The transmittance is 45.5% or more,
The reflectance after 500 hours of heating and humidification test at 60 ° C and 90% RH is 2.5% or less,
A circularly polarizing plate with an antireflection layer. According to claim 1,
The polarizer and the protective layer on the side of the antireflection layer are bonded via a first adhesive layer, the polarizer and the retardation layer are bonded via a second adhesive layer,
At least one of the adhesive of the first adhesive layer and the second adhesive layer is composed of an active energy ray-curable adhesive composition,
When the said active energy ray-curable adhesive composition makes composition whole quantity 100 weight%, SP value is 29.0 (MJ/m<3>) ^1/2 or more 0.0 wt% to 4.0 wt% of the active energy ray-curable compound (A) of 32.0 (MJ/m3) ^1/2 or less, SP value of 18.0 (MJ/m3) ^1/2 or more and 21.0 (MJ/m3) ^1/2 or less 5.0 wt% to 98.0 wt% of the active energy ray-curable compound (B), and an active energy ray-curable compound (C) having an SP value of 21.0 (MJ/m3) ^1/2 or more and 26.0 (MJ/m3) ^1/2 or less containing 5.0 wt% to 98.0 wt%,
A circularly polarizing plate with an antireflection layer. 3. The method of claim 1 or 2,
A circularly polarizing plate with an antireflection layer, wherein the reflectance of the antireflection layer is 1.5% or less. 4. The method according to any one of claims 1 to 3,
A circularly polarizing plate with an antireflection layer, wherein Re (550) of the retardation layer is 100 nm to 200 nm, and the angle between the slow axis of the retardation layer and the absorption axis of the polarizer is 40° to 50° or 130° to 140°. . 5. The method according to any one of claims 1 to 4,
A circularly polarizing plate with an antireflection layer, wherein the retardation layer is composed of a stretched film of a resin film, and Re(450)/Re(550) is 0.80 to 1.03:
Here, Re(450) and Re(550) are in-plane retardation measured with the light of wavelength 450nm and 550nm at 23 degreeC, respectively. The circularly polarizing plate with an antireflection layer according to any one of claims 1 to 5 is provided on the visual recognition side,
The antireflection layer of the circularly polarizing plate with the antireflection layer is disposed on the viewing side,
The reflectance is less than 40%,
image display device. 7. The method of claim 6,
The image display apparatus which is an organic electroluminescent display apparatus.

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