TW201706641A - Polarizing plate with a retardation layer and image display apparatus - Google Patents

Abstract

There is provided a thin polarizing plate with a retardation layer excellent in reworkability. A polarizing plate with a retardation layer according to the present invention includes: a polarizing plate including a polarizer and a protective layer on at least one side of the polarizer; a retardation layer; a first adhesive layer configured to bond the polarizing plate and the retardation layer; and a second adhesive layer arranged as an outermost layer on an opposite side of the retardation layer to the polarizing plate. An average linear expansion coefficient of the second adhesive layer when an ambient temperature is changed from -150 DEG C to 20 DEG C is 38.0 (*10<SP>-5</SP>/ DEG C) or more, and is larger than an average linear expansion coefficient of the first adhesive layer when an ambient temperature is changed from -150 DEG C to 20 DEG C.

Description

Polarizing plate with phase difference layer and image display device

The present invention relates to a polarizing plate with a phase difference layer and an image display device using the same.

In recent years, image display devices typified by liquid crystal display devices and organic EL (electroluminescence) display devices have rapidly spread. In the image display device, a polarizing plate and a phase difference plate are typically used. In practical applications, a polarizing plate with a phase difference layer formed by integrating a polarizing plate and a phase difference plate is widely used (for example, Japanese Patent No. 3325560). In this case, recently, with the image display device The demand for thinning is enhanced, and the demand for thinning of the polarizing plate with a phase difference layer is also increasing.

In addition, for the purpose of preventing the variation in quality and/or the efficiency of assembly of the image display device, the polarizing plate with the retardation layer is typically provided with a state in which an adhesive layer containing an adhesive or an adhesive is attached in advance. The lower layer is attached to a liquid crystal cell or an organic EL unit (hereinafter, collectively referred to as a display unit). In this case, if a foreign matter such as a contaminant or a bubble is mixed in the display unit, the portion may become a visually impaired. Therefore, the polarizing plate with the retardation layer to which the error is applied is peeled off and removed from the display unit, and the display unit is reused. Such an operation in the assembly of an image display device is referred to as rework.

In recent years, liquid nitrogen has sometimes been used for reprocessing. In the case where the thickness of the polarizing plate is thick, even if the liquid nitrogen cannot be reworked, the display unit and the phase difference layer are The polarizing plate is peeled off, and it can be reworked by hand, so that there is no problem. On the other hand, when the thickness of the polarizing plate is thin, if the rework is to be manually performed, the polarizing plate with the retardation layer is broken and cannot be peeled off, and it is desirable to reprocess the self-display by liquid nitrogen. A thin polarizing plate with a phase difference layer that is well peeled off.

The present invention has been made in order to solve the above-mentioned problems, and a main object thereof is to provide a thin phase difference layer-attached polarizing plate which is excellent in reworkability.

The phase difference layer-attached polarizing plate of the present invention comprises: a polarizing plate comprising a polarizing element and a protective layer on at least one side of the polarizing element; a phase difference layer; a first bonding layer, the polarizing plate and the phase The second layer is disposed as the outermost layer of the phase difference layer opposite to the polarizing plate. In the present invention, the average linear expansion coefficient of the second adhesive layer when the ambient temperature is changed from -150 ° C to 20 ° C is 38.0 (×10 ⁻⁵ /° C.) or more, and is greater than the ambient temperature from -150 ° C to The average linear expansion coefficient of the first subsequent layer at 20 ° C.

In one embodiment, the total thickness of each of the polarizing plates with the retardation layer other than the second adhesive layer is 140 μm or less.

In one embodiment, the retardation layer contains a polycarbonate resin film.

In one embodiment, the polarizing plate with the retardation layer further has another retardation layer on the outer side of the retardation layer.

In one embodiment, the retardation layer is an alignment cured layer of a liquid crystal compound.

In one embodiment, the retardation layer has a laminated structure of a alignment-cured layer of the first liquid crystal compound and an alignment-cured layer of the second liquid crystal compound.

In one embodiment, the polarizing plate with the retardation layer further has a conductive layer or an isotropic substrate with a conductive layer on the outer side of the retardation layer.

According to another aspect of the present invention, an image display device is provided. This image display device includes the above-described polarizing plate with a phase difference layer.

According to the present invention, in the thin polarizing plate with a phase difference layer, the average linear expansion coefficient of the polarizing plate and the retardation layer and the subsequent layer within a specific temperature range is optimized, and the average line is expanded. The coefficient is optimized in relation to the average linear expansion coefficient of the adhesive layer to be bonded to the outermost layer of the display unit over a specific temperature range, and the reprocessing (especially the rework at low temperature using liquid nitrogen) is remarkably suppressed. The defect (typically, the phase difference layer peeled off from the polarizing plate remains in the display unit).

10‧‧‧Polar plate

11‧‧‧Polarized components

12‧‧‧1st protective layer

13‧‧‧2nd protective layer

20‧‧‧ phase difference layer

21‧‧‧1st alignment hardened layer

22‧‧‧2nd alignment hardened layer

30‧‧‧1st layer

40‧‧‧2nd layer

50‧‧‧ phase difference layer

60‧‧‧Electrically conductive layer or isotropic substrate with conductive layer

100‧‧‧Polarizer with phase difference layer

101‧‧‧Polarizer with phase difference layer

102‧‧‧Polarizer with phase difference layer

Fig. 1 is a schematic cross-sectional view showing a polarizing plate with a retardation layer according to an embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view showing a polarizing plate with a retardation layer according to another embodiment of the present invention.

Fig. 3 is a schematic cross-sectional view showing a polarizing plate with a retardation layer according to still another embodiment of the present invention.

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

(Definition of terms and symbols)

The definitions of terms and symbols in this specification are as follows.

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

"nx" is the refractive index in which the refractive index in the plane becomes the largest (ie, the direction of the slow axis), and "ny" is the refractive index in the direction orthogonal to the late phase axis (ie, the direction of the phase axis) The rate, "nz" is the refractive index in the thickness direction.

(2) In-plane phase difference (Re)

"Re(λ)" is an in-plane phase difference measured by light of a wavelength λ nm at 23 °C. For example, "Re (550)" is an in-plane phase difference measured by light having a wavelength of 550 nm at 23 °C. When the thickness of the layer (film) is d (nm), Re (λ) is obtained by the formula: Re (λ) = (nx - ny) × d.

(3) Phase difference in the thickness direction (Rth)

"Rth(λ)" is a phase difference in the thickness direction measured by light having a wavelength of λ nm at 23 °C. For example, "Rth (550)" is a phase difference in the thickness direction measured at 23 ° C using light having a wavelength of 550 nm. When the thickness of the layer (film) is d (nm), Rth (λ) is obtained by the formula: Rth (λ) = (nx - nz) × d.

(4) Nz coefficient

The Nz coefficient is obtained by Nz = Rth / Re.

A. The overall composition of the polarizing plate with phase difference layer

Fig. 1 is a schematic cross-sectional view showing a polarizing plate with a retardation layer according to an embodiment of the present invention. The phase difference layer-attached polarizing plate 100 of the present embodiment includes a polarizing plate 10, a retardation layer 20, a first subsequent layer 30, which is followed by the polarizing plate 10 and the retardation layer 20, and a second subsequent layer 40. It is the outermost layer of the phase difference layer 20 opposite to the polarizing plate 10. The second adhesive layer 40 is followed by a polarizing plate with a phase difference layer and a display unit (for example, a liquid crystal cell or an organic EL unit) of the image display device. The polarizing plate 10 includes a polarizing element 11 , a first protective layer 12 disposed on one side of the polarizing element 11 , and a second protective layer 13 disposed on the other side of the polarizing element 11 . One of the first protective layer 12 and the second protective layer 13 may be omitted depending on the purpose. For example, when the retardation layer 20 can also function as a protective layer of the polarizing element 11, the second protective layer 13 can be omitted.

As shown in FIG. 2, in the polarizing plate 101 with a phase difference layer according to another embodiment, another phase difference layer 50 and/or a conductive layer or an isotropic substrate 60 with a conductive layer may be disposed. The other retardation layer 50 and the conductive layer or the isotropic base material 60 with the conductive layer are typically disposed on the outer side of the phase difference layer 20 (opposite side of the polarizing plate 10). Another phase difference layer 50 and a conductive layer Or an isotropic substrate 60 with a conductive layer is typically disposed sequentially from the phase difference layer 20 side. The other retardation layer 50 and the conductive layer or the isotropic substrate 60 with the conductive layer are representatively any layer as desired, and either or both may be omitted. Further, for convenience, the retardation layer 20 may be referred to as a first retardation layer, and the other retardation layer 50 may be referred to as a second retardation layer. Furthermore, when a conductive layer or an isotropic substrate with a conductive layer is provided, the phase difference layer-attached polarizing plate can be applied to form a touch feeling between a display unit (for example, an organic EL unit) and a polarizing plate. The so-called touch panel type input display device of the detector.

In one embodiment, the first retardation layer 20 is made of a resin film. In another embodiment, the first retardation layer 20 may be an alignment cured layer of a liquid crystal compound. In this embodiment, the first retardation layer 20 may be a single layer or may have a laminated structure of the first alignment solidified layer 21 and the second alignment hardened layer 22 as shown in FIG. In addition, the resin film is described in detail in item C-2, and the alignment hardening layer of the liquid crystal compound will be described in detail in item C-3.

The above embodiments may be combined as appropriate, and the constituent elements in the above embodiments may be modified in a clear manner in the art. For example, the second retardation layer 50 and/or the conductive layer or the isotropic substrate 60 with the conductive layer may be provided on the polarizing plate 102 with the retardation layer of FIG. Further, for example, the configuration of the isotropic base material 60 on which the conductive layer is provided on the outer side of the second retardation layer 50 may be replaced by an optically equivalent configuration (for example, a laminate of the second retardation layer and the conductive layer).

In the embodiment of the present invention, the average linear expansion coefficient (hereinafter sometimes simply referred to as an average linear expansion coefficient) of the second adhesive layer 40 when the ambient temperature is changed from -150 ° C to 20 ° C is 38.0 (×10 ^-5 / Above °C) is preferably 39.0 (×10 ^-5 /°C) or more, more preferably 40.0 (×10 ^-5 /°C) or more. The upper limit of the average linear expansion coefficient of the second subsequent layer is, for example, 200 (×10 ^-5 /°C). When the average linear expansion coefficient of the second adhesive layer is in such a range, the polarizing plate with the retardation layer can be favorably peeled off from the display unit in reworking (especially, reworking at a low temperature using liquid nitrogen). Further, the average linear expansion coefficient of the second adhesive layer is larger than the average linear expansion coefficient of the first adhesive layer. By setting in this way, in reworking (especially reworking at a low temperature using liquid nitrogen), peeling of the polarizing plate 10 and the first retardation layer 20 can be favorably prevented, and the display unit and the phase difference layer are provided. Since the polarizing plate is favorably peeled off, it is possible to remarkably suppress the occurrence of defects in rework (typically, the phase difference layer peeled off from the polarizing plate remains on the display unit). Then the difference between the first and then the second average linear coefficient of expansion layer average linear expansion coefficient of the layer is preferably not less than ^{1.5 (× 10 -5 / ℃)} , more preferably ^{2.0 (× 10 -5 / ℃)} ~ 4.0 ( × 10 ^-5 / ℃). If the difference between the average linear expansion coefficients is such a range, the disadvantage in reworking (especially reworking at a low temperature using liquid nitrogen) can be more significantly suppressed. Further, the average coefficient of linear expansion can be determined according to the TMA measurement in accordance with JIS K 7197.

The total thickness of the polarizing plate with the retardation layer is preferably 140 μm or less, more preferably 50 μm to 135 μm, still more preferably 55 μm to 80 μm. In the case where the thickness of the polarizing plate with the phase difference layer is very thin, the occurrence of defects in reworking (especially reworking at low temperature using liquid nitrogen) is remarkable, but according to the present invention, even with a phase difference layer When the thickness of the polarizing plate is so thin, the occurrence of defects can be suppressed extremely well. Further, the total thickness of the polarizing plate with the retardation layer means the total thickness of all the layers of the polarizing plate constituting the retardation layer other than the second adhesive layer 40.

Hereinafter, each layer constituting the polarizing plate with the retardation layer, an optical film, an adhesive, and an adhesive will be described in more detail.

B. Polarizer

B-1. Polarizing element

As the polarizing element 11, any appropriate polarizing element can be employed. For example, the resin film forming the polarizing element may be a single layer of a resin film, or may be a laminate of two or more layers.

Specific examples of the polarizing element including the resin film of a single layer include a hydrophilicity such as a polyvinyl alcohol (PVA) film, a partially formalized PVA film, or an ethylene-vinyl acetate copolymer partial saponified film. Molecular film is formed by dyeing and stretching treatment of dichroic materials such as iodine or dichroic dye; dehydration of PVA or dechlorination of polyvinyl chloride A polyolefin-based alignment film such as a hydrogen-treated product. In terms of excellent optical characteristics, it is preferred to use a polarizing element obtained by dyeing a PVA-based film with iodine and performing uniaxial stretching.

The above dyeing with iodine is carried out, for example, by immersing the PVA-based film in an aqueous iodine solution. The stretching ratio of the uniaxial stretching is preferably 3 to 7 times. The stretching can be carried out after the dyeing treatment, or can be carried out while dyeing one side. Further, it is also possible to perform dyeing after stretching. The PVA film is subjected to a wetting treatment, a crosslinking treatment, a washing treatment, a drying treatment, and the like as necessary. For example, by immersing the PVA-based film in water and washing it with water before dyeing, the dirt or anti-blocking agent on the surface of the PVA-based film can be washed, and the PVA-based film can be moistened to prevent uneven dyeing.

Specific examples of the polarizing element obtained by using the laminated body include a laminate of a resin substrate and a PVA-based resin layer (PVA-based resin film) laminated on the resin substrate, or a resin substrate and coating. A polarizing element obtained by laminating a PVA-based resin layer of a resin substrate. A polarizing element obtained by using a resin substrate and a laminate obtained by coating a PVA-based resin layer formed on the resin substrate can be produced, for example, by applying a PVA-based resin solution to a resin substrate and drying it. A PVA-based resin layer is formed on the resin substrate to obtain a laminate of the resin substrate and the PVA-based resin layer, and the PVA-based resin layer is formed into a polarizing element by extending and dyeing the laminate. In the present embodiment, the extension typically includes immersing the layered body in an aqueous boric acid solution and extending it. Further, the extension may optionally include extending the laminate at a high temperature (for example, 95 ° C or higher) in the air before extending in the aqueous boric acid solution. The laminated body of the obtained resin substrate/polarizing element can be used as it is (that is, the resin substrate can be used as a protective layer of the polarizing element), or the resin substrate can be peeled off from the laminated body of the resin substrate/polarizing element. The release area layer is used in accordance with any suitable protective layer for the purpose. The details of the method for producing such a polarizing element are described, for example, in Japanese Laid-Open Patent Publication No. 2012-73580. The entire disclosure of this publication is incorporated herein by reference.

The thickness of the polarizing element is preferably 15 μm or less, more preferably 1 μm to 12 μm, and further It is preferably 3 μm to 12 μm, and more preferably 3 μm to 8 μm. According to the present invention, even if the polarizing element (resulting as a polarizing plate with a retardation layer) is very thin, the occurrence of defects in reworking (especially reworking at a low temperature using liquid nitrogen) can be remarkably suppressed. Moreover, when the thickness of the polarizing element is in such a range, the curl at the time of heating can be favorably suppressed, and the appearance durability at the time of favorable heating can be acquired.

The boronic acid content of the polarizing element is preferably 18% by weight or more, more preferably 18% by weight to 25% by weight. When the boric acid content of the polarizing element is in such a range, the synergistic effect with the iodine content described later can maintain the ease of curl adjustment at the time of bonding, and the curl during heating can be favorably suppressed, and the heating can be improved. The appearance of the time is durable. The boric acid content can be calculated, for example, by the neutralization method using the following formula as the amount of boric acid contained per unit weight of the polarizing element.

The iodine content of the polarizing element is preferably 2.1% by weight or more, more preferably 2.1% by weight to 3.5% by weight. When the iodine content of the polarizing element is in such a range, the synergistic effect with the boric acid content can maintain the ease of curl adjustment at the time of bonding, and the curl during heating can be favorably suppressed, and the heating can be improved. Durability of appearance. In the present specification, the "iodine content" means the amount of all iodine contained in a polarizing element (PVA-based resin film). More specifically, in the polarizing element, iodine exists in the form of iodide ion (I ^- ), iodine molecule (I ₂ ), polyiodide ion (I ₃ ^- , I ₅ ^- ), and the iodine content in the present specification is Refers to the amount of iodine in all such forms. The iodine content can be calculated, for example, by a calibration curve method of fluorescent X-ray analysis. Further, the polyiodide ion is present in the polarizing element in a state in which a PVA-iodine complex is formed. By forming such a complex, absorption dichroism can be exhibited in the wavelength range of visible light. Specifically, the complex of PVA and triiodide ion (PVA.I ₃ ^- ) has an absorption peak near 470 nm, and the complex of PVA and penta iodide ion (PVA.I ₅ ^- ) has absorption at around 600 nm. peak. As a result, the polyiodide ions can absorb light in a wide range of visible light depending on the form. On the other hand, the iodide ion (I ^- ) has an absorption peak near 230 nm and does not substantially participate in the absorption of visible light. Therefore, the polyiodide ion existing in the state of the complex with PVA can mainly participate in the absorption performance of the polarizing element.

The polarizing element preferably exhibits absorption dichroism at any wavelength from 380 nm to 780 nm. The monomer transmittance of the polarizing element is 43.0% to 46.0%, 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, still more preferably 99.9% or more.

B-2. First protective layer

The first protective layer 12 is formed of any suitable film which can be used as a protective layer for a polarizing element. Specific examples of the material which is a main component of the film include a cellulose resin such as triethyl cellulose (TAC), a polyester resin, a polyvinyl alcohol system, a polycarbonate system, and a polyamido compound. Polyimine, polyether oxime, polyfluorene, polystyrene, polycondensate A transparent resin such as an olefin, a polyolefin, a (meth)acrylic or an acetate. Further, examples thereof include thermosetting resins such as (meth)acrylic acid, urethane-based, (meth)acrylic acid urethane-based, epoxy-based, and polyfluorene-based resins, and ultraviolet curable resins. . Further, for example, a glassy polymer such as a siloxane-based polymer may be mentioned. Further, a polymer film described in JP-A-2001-343529 (WO 01/37007) can also be used. As the material of the film, for example, a thermoplastic resin having a substituted or unsubstituted quinone imine group in a side chain and a substituted or unsubstituted phenyl and nitrile group in a side chain can be used. The resin composition may, for example, be a resin composition containing an alternating copolymer of isobutylene and N-methylmaleimide and an acrylonitrile-styrene copolymer. The polymer film can be, for example, an extrusion molded product of the above resin composition.

As described below, the polarizing plate with a retardation layer of the present invention is typically disposed on the viewing side of the image display device, and the first protective layer 12 is typically disposed on the viewing side thereof. Therefore, for the first protective layer 12, hard coating treatment, anti-reflection treatment, and anti-blocking may be performed as needed. Surface treatment such as treatment, anti-glare treatment. Further, in the first protective layer 12, it is also possible to perform processing for improving the visibility when viewed through polarized sunglasses (typically, an (elliptical) circular polarizing function is given and an ultra-high phase difference is imparted). By performing such a process, excellent visibility can be achieved even when the display screen is viewed through a polarizing lens such as polarized sunglasses. Therefore, the polarizing plate with the phase difference layer can also be preferably applied to an image display device which can be used outdoors.

Regarding the thickness of the first protective layer, any appropriate thickness can be employed as long as the difference between the thickness of the desired polarizing plate and the thickness of the second protective layer can be obtained. The thickness of the first protective layer is, for example, 10 μm to 50 μm, preferably 15 μm to 40 μm. Further, in the case of performing the surface treatment, the thickness of the first protective layer is the thickness including the thickness of the surface treatment layer.

B-3. Second protective layer

Further, the second protective layer 13 is also formed of any appropriate film which can be used as a protective layer of the polarizing element. The material which becomes a main component of the film is as described in the above item B-2 regarding the first protective layer. The second protective layer 13 is preferably optically isotropic. In the present specification, "optical isotropic" means that the in-plane retardation Re (550) is 0 nm to 10 nm, and the thickness direction retardation Rth (550) is -10 nm to +10 nm.

The thickness of the second protective layer is, for example, 15 μm to 35 μm, preferably 20 μm to 30 μm. The difference between the thickness of the first protective layer and the thickness of the second protective layer is preferably 15 μm or less, and more preferably 10 μm or less. When the difference in thickness is in such a range, the curl at the time of bonding can be favorably suppressed. The thickness of the first protective layer may be the same as the thickness of the second protective layer, or the first protective layer may be thicker or the second protective layer may be thicker. Typically, the first protective layer is thicker than the second protective layer.

C. 1st phase difference layer

C-1. Characteristics of the first phase difference layer

The first retardation layer 20 may have any suitable optical characteristics and/or mechanical properties depending on the purpose. The first retardation layer 20 typically has a slow phase axis. In one embodiment, the first phase The angle θ between the slow phase axis of the difference layer 20 and the absorption axis of the polarizing element 11 is preferably 38 to 52, more preferably 42 to 48, and still more preferably about 45. When the angle θ is such a range, by using the first retardation layer as the λ/4 plate, a phase difference layer having excellent circular polarization characteristics (resulting in excellent anti-reflection characteristics) can be obtained as follows. Polarized plate.

The first retardation layer preferably has a relationship in which the refractive index characteristic shows nx>ny≧nz. The first retardation layer is typically provided to impart anti-reflection properties to the polarizing plate, and in one embodiment, functions as a λ/4 plate. In this case, the in-plane retardation Re (550) of the first retardation layer is preferably from 80 nm to 200 nm, more preferably from 100 nm to 180 nm, still more preferably from 110 nm to 170 nm. Furthermore, "ny=nz" here includes not only the case where ny and nz are completely equal, but also the case where they are substantially equal. Therefore, there may be a case where ny < nz within a range that does not impair the effects of the present invention.

The Nz coefficient of the first retardation layer is preferably from 0.9 to 3, more preferably from 0.9 to 2.5, still more preferably from 0.9 to 1.5, still more preferably from 0.9 to 1.3. By satisfying such a relationship, when the obtained phase difference layer-attached polarizing plate is used for an image display device, a very excellent reflected hue can be achieved.

The first retardation layer can display an inverse dispersion wavelength characteristic in which the phase difference value becomes larger as the wavelength of the measurement light becomes larger, and can also display a positive wavelength dispersion characteristic in which the phase difference value becomes smaller with the wavelength of the measurement light, and can also display the phase. The difference has almost no flat wavelength dispersion characteristic as a function of the wavelength of the measured light. In one embodiment, the first retardation layer exhibits an inverse dispersion wavelength characteristic. In this case, the Re(450)/Re(550) of the retardation layer is preferably 0.8 or more and less than 1, more preferably 0.8 or more and 0.95 or less. With such a configuration, very excellent anti-reflection characteristics can be achieved.

The absolute value of the first retardation layer including the photoelastic coefficient is preferably 2 × 10 ^-11 m ² /N or less, more preferably 2.0 × 10 ^-13 m ² /N to 1.5 × 10 ^-11 m ² /N, and further preferably ^{1.0 × 10 -12 m 2 /N~1.2×10 -11} m 2 / N of the resin. When the absolute value of the photoelastic coefficient is in such a range, the phase difference change is less likely to occur when a contraction stress is generated during heating. As a result, thermal unevenness of the obtained image display device can be satisfactorily prevented.

C-2. First retardation layer composed of a resin film

When the first retardation layer is composed of a resin film, the thickness thereof is preferably 60 μm or less, preferably 30 μm to 55 μm. When the thickness of the first retardation layer is in such a range, the curl at the time of heating can be satisfactorily suppressed, and the curl at the time of bonding can be favorably adjusted.

The first retardation layer 20 can be formed of any appropriate resin film that satisfies the characteristics described in the above item C-1. Typical examples of such a resin include a cyclic olefin resin, a polycarbonate resin, a cellulose resin, a polyester resin, a polyvinyl alcohol resin, a polyamide resin, and a polyimide. Resin, polyether resin, polystyrene resin, acrylic resin. When the first retardation layer is composed of a resin film exhibiting reverse dispersion wavelength characteristics, a polycarbonate resin can be preferably used.

As the polycarbonate resin, any suitable polycarbonate resin can be used as long as the effect of the present invention is obtained. Preferably, the polycarbonate resin comprises: a structural unit derived from a lanthanide dihydroxy compound; a structural unit derived from an isosorbide-based dihydroxy compound; and a source selected from the group consisting of an alicyclic diol, an alicyclic dimethanol, A structural unit of at least one dihydroxy compound of a group consisting of di-/tri- or polyethylene glycol, and alkylene glycol or spirodiol. Preferably, the polycarbonate resin comprises: a structural unit derived from a lanthanide dihydroxy compound; a structural unit derived from an isosorbide-based dihydroxy compound; and a structural unit derived from an alicyclic dimethanol and/or derived from a structural unit derived from -3 or polyethylene glycol; further preferably comprising: a structural unit derived from a lanthanide dihydroxy compound; a structural unit derived from an isosorbide dihydroxy compound; and derived from a second-/three - or a structural unit of polyethylene glycol. The polycarbonate resin may also contain structural units derived from other dihydroxy compounds as needed. In addition, the details of the polycarbonate resin which can be preferably used in the present invention are described in, for example, Japanese Patent Laid-Open No. Hei. No. Hei. To this manual.

The glass transition temperature of the polycarbonate resin is preferably 110 ° C or more and 150 ° C or less, more preferably 120 ° C or more and 140 ° C or less. If the glass transition temperature is too low, heat resistance is deteriorated. The tendency is to cause dimensional change after film formation, and sometimes the image quality of the obtained organic EL panel is lowered. When the glass transition temperature is too high, the molding stability at the time of film formation may be deteriorated, and the transparency of the film may be impaired. The glass transition temperature was determined in accordance with JIS K 7121 (1987).

The molecular weight of the above polycarbonate resin can be expressed by a specific viscosity. The specific viscosity was determined by using dichloromethane as a solvent, and the polycarbonate concentration was accurately prepared to 0.6 g/dL, and it was measured at 20.0 ° C ± 0.1 ° C using a Ubbelohde viscometer. The lower limit of the rich viscosity is usually preferably 0.30 dL/g, more preferably 0.35 dL/g or more. The upper limit of the rich viscosity is usually preferably 1.20 dL/g, more preferably 1.00 dL/g, and still more preferably 0.80 dL/g. When the specific viscosity is less than the above lower limit, there is a problem that the mechanical strength of the molded article becomes small. On the other hand, when the specific viscosity is larger than the above upper limit, there is a problem that the fluidity at the time of molding is lowered and the productivity or moldability is lowered.

A commercially available film can also be used as the polycarbonate resin film. Specific examples of the commercial products include the trade names "PURE-ACE WR-S", "PURE-ACE WR-W", "PURE-ACE WR-M" manufactured by Teijin Co., Ltd., and the product name manufactured by Nitto Denko Corporation. "NRF".

The first retardation layer 20 can be obtained, for example, by stretching a film formed of the above polycarbonate resin. As a method of forming a film from a polycarbonate resin, any appropriate molding method can be employed. Specific examples thereof include compression molding, transfer molding, injection molding, extrusion molding, blow molding, powder molding, FRP (fiber reinforced plastics) molding, and casting coating. (for example, casting method), calendering method, hot pressing method. It is preferably an extrusion molding method or a casting coating method. The reason for this is that the smoothness of the obtained film can be improved to obtain good optical uniformity. The molding conditions can be appropriately set depending on the composition and type of the resin to be used and the characteristics desired for the retardation layer. Further, as described above, since a variety of film products are commercially available for polycarbonate resins, the commercially available film can be directly supplied to the stretching treatment.

The thickness of the resin film (unstretched film) can be set to any appropriate value depending on the desired thickness of the first retardation layer, desired optical characteristics, elongation conditions to be described later, and the like. It is preferably 50 μm to 300 μm.

The above extension may employ any suitable extension method, extension conditions (e.g., extension temperature, extension ratio, extension direction). Specifically, various extension methods such as free end extension, fixed end extension, free end contraction, and fixed end contraction may be used alone, and may be used simultaneously or sequentially. Regarding the extending direction, it can be carried out in various directions or dimensions such as the longitudinal direction, the width direction, the thickness direction, and the oblique direction. The glass transition temperature (Tg) of the stretching temperature with respect to the resin film is preferably from Tg -30 ° C to Tg + 60 ° C, more preferably from Tg - 10 ° C to Tg + 50 ° C.

A retardation film having the above-described desired optical characteristics (for example, refractive index characteristics, in-plane retardation, and Nz coefficient) can be obtained by appropriately selecting the above-described stretching method and stretching conditions.

In one embodiment, the retardation film is produced by uniaxially stretching the resin film or uniaxially extending the fixed end. Specific examples of the uniaxial stretching of the fixed end include a method in which the resin film is extended in the longitudinal direction (lateral direction) while moving in the longitudinal direction. The stretching ratio is preferably from 1.1 times to 3.5 times.

In another embodiment, the retardation film can be produced by continuously extending the elongated resin film obliquely in the direction of the angle θ with respect to the longitudinal direction. By using an oblique extension, it is possible to obtain an elongated stretch film having an alignment angle (having a slow phase axis in the direction of the angle θ) with respect to the longitudinal direction of the film, for example, when laminated with a polarizing element. A roll-to-roll operation can be implemented, which simplifies the manufacturing steps. Furthermore, the angle θ may be an angle formed by the absorption axis of the polarizing element and the retardation axis of the phase difference layer in the polarizing plate with the phase difference layer. As described above, the angle θ is preferably from 38 to 52, more preferably from 42 to 48, still more preferably about 45.

As the stretching machine for obliquely extending, for example, a tenter type stretching machine capable of adding a feed force or a stretching force or a winding force at different speeds in the lateral direction and/or the longitudinal direction can be cited. The tenter type extender has a horizontal single-axis stretching machine, a simultaneous double-axis stretching machine, etc., but as long as it can be long The strip-shaped resin film is continuously extended obliquely, and any appropriate stretching machine can be used.

By appropriately controlling the speeds of the left and right in the extension machine, respectively, a phase difference layer having a desired in-plane phase difference and having a slow phase axis in the desired direction can be obtained (substantially a strip-like phase difference) membrane).

The extension temperature of the film may vary depending on the in-plane retardation value and thickness desired for the retardation layer, the kind of the resin to be used, the thickness of the film to be used, the stretching ratio, and the like. Specifically, the extension temperature is preferably from Tg-30 ° C to Tg + 30 ° C, more preferably from Tg - 15 ° C to Tg + 15 ° C, most preferably from Tg - 10 ° C to Tg + 10 ° C. By extending at such a temperature, the first retardation layer having appropriate characteristics in the present invention can be obtained. Further, the glass transition temperature of the constituent material of the Tg film.

C-3. The first retardation layer composed of the alignment solidified layer of the liquid crystal compound

The first retardation layer 20 may also be an alignment cured layer of a liquid crystal compound. By using a liquid crystal compound, the difference between nx and ny of the obtained phase difference layer can be significantly increased as compared with the non-liquid crystal material, so that the thickness of the phase difference layer which can be used to obtain the desired in-plane retardation is remarkably reduced. . As a result, it is possible to further reduce the thickness of the polarizing plate with the retardation layer. When the first retardation layer 20 is composed of an alignment-cured layer of a liquid crystal compound, the thickness thereof is preferably from 0.5 μm to 7 μm, more preferably from 1 μm to 5 μm. By using a liquid crystal compound, the in-plane retardation equivalent to that of the resin film can be achieved with a thickness significantly smaller than that of the resin film.

In the present specification, the term "alignment-cured layer" means a layer in which a liquid crystal compound is aligned in a specific direction in a layer and its alignment state is fixed. Further, the "alignment-cured layer" includes the concept of an alignment hardened layer obtained by curing a liquid crystal monomer as described below. In the present embodiment, the rod-shaped liquid crystal compounds are aligned (horizontal alignment) in a state in which they are arranged in the slow axis direction of the first retardation layer. The liquid crystal compound is a liquid crystal compound (nematic liquid crystal) in which a liquid crystal phase is a nematic phase. As such a liquid crystal compound, for example, a liquid crystal polymer or a liquid crystal monomer can be used. The liquid crystallinity of the liquid crystal compound can be expressed in either a lyotropic or thermotropic type. Liquid crystal polymer and liquid crystal monomer can be used separately or in groups Hehe.

In the case where the liquid crystal compound is a liquid crystal monomer, the liquid crystal monomer is preferably a polymerizable monomer and a crosslinkable monomer. The reason for this is that the liquid crystal monomer can be fixed by polymerizing or crosslinking (i.e., hardening) the liquid crystal monomer. After the liquid crystal monomers are aligned, for example, when the liquid crystal monomers are polymerized or crosslinked with each other, the above alignment state can be fixed. Here, a polymer is formed by polymerization, and a three-dimensional network structure is formed by crosslinking, and these are non-liquid crystalline. Therefore, the formed first retardation layer does not cause a transition to the liquid crystal phase, the glass phase, or the crystal phase due to, for example, a temperature change characteristic of the liquid crystal compound. As a result, the first retardation layer is a retardation layer which is extremely excellent in stability without being affected by temperature change.

The temperature range in which the liquid crystal monomer exhibits liquid crystallinity differs depending on the type thereof. Specifically, the temperature range is preferably from 40 ° C to 120 ° C, more preferably from 50 ° C to 100 ° C, most preferably from 60 ° C to 90 ° C.

As the liquid crystal monomer, any appropriate liquid crystal monomer can be employed. For example, Japanese Patent Laid-Open Publication No. 2002-533742 (WO 00/37585), EP 358208 (US Pat. No. 5,211, 877), EP 66 137 (US Pat. No. 4,388, 453), WO 93/22397, EP 0261712, DE 19504224, DE 4408171, and GB 2280445, etc. The polymerizable liquid crystal priming compound described above. Specific examples of such a polymerizable liquid crystal priming compound include, for example, trade name LC242 of BASF Corporation, trade name E7 of Merck Corporation, and trade name LC-Sillicon-CC3767 of Wacker-Chem Company. As the liquid crystal monomer, for example, a nematic liquid crystal monomer is preferable.

The alignment-cured layer of the liquid crystal compound can be formed by subjecting a surface of a specific substrate to an alignment treatment, and applying a coating liquid containing a liquid crystal compound to the surface to make the liquid crystal compound in a direction corresponding to the alignment treatment described above. Orientation and fixing the alignment state. In one embodiment, the substrate is any suitable resin film, and the alignment cured layer formed on the substrate can be transferred to the surface of the polarizing plate 10. In another embodiment, the substrate may be the second protective layer 13. In this case, the transfer step is omitted, and the roll-to-roll is continuously laminated from the formation of the cured layer (first retardation layer), so that the productivity is further improved. high.

As the above alignment treatment, any appropriate alignment treatment can be employed. Specific examples include mechanical alignment treatment, physical alignment treatment, and chemical alignment treatment. Specific examples of the mechanical alignment treatment include a rubbing treatment and an elongation treatment. Specific examples of the physical alignment treatment include a magnetic field alignment treatment and an electric field alignment treatment. Specific examples of the chemical alignment treatment include an oblique vapor deposition method and a photo alignment treatment. The processing conditions of the various alignment treatments may be any suitable conditions depending on the purpose.

The alignment of the liquid crystal compound is carried out by treatment at a temperature at which the liquid crystal phase is displayed depending on the kind of the liquid crystal compound. By performing such temperature treatment, the liquid crystal compound is in a liquid crystal state, and the liquid crystal compound is aligned in accordance with the alignment treatment direction of the surface of the substrate.

In one embodiment, the fixation in the alignment state is carried out by cooling the liquid crystal compound aligned as described above. In the case where the liquid crystal compound is a polymerizable monomer or a crosslinkable monomer, the fixation in the alignment state is carried out by subjecting the liquid crystal compound aligned as described above to a polymerization treatment or a crosslinking treatment.

Specific examples of the liquid crystal compound and a method of forming the alignment cured layer are described in Japanese Laid-Open Patent Publication No. 2006-163343. The description of this publication is incorporated herein by reference.

In one embodiment, as shown in FIG. 3, the alignment hardening layer may have a laminated structure of the first alignment solidified layer 21 and the second alignment solidified layer 22. In this case, either of the first alignment cured layer 21 and the second alignment cured layer 22 can function as a λ/4 plate, and the other can function as a λ/2 plate. Therefore, the thickness of the first alignment solidified layer 21 and the second alignment solidified layer 22 can be adjusted so that the desired in-plane phase difference of the λ/4 plate or the λ/2 plate can be obtained. For example, when the first alignment solidified layer 21 functions as a λ/4 plate and the second alignment solidified layer 22 functions as a λ/2 plate, the thickness of the first alignment solidified layer 21 is, for example, 1 μm to 1.3 μm. The thickness of the second alignment solidified layer 22 is, for example, 1.9 μm to 2.1 μm. The first alignment solidified layer 21 and the second alignment solidified layer 22 may be laminated so as to form, for example, 50° each of the retardation axes. Lamination is carried out at an angle of 70°, preferably about 60°. According to this configuration, characteristics close to the ideal reverse wavelength dispersion characteristics can be obtained, and as a result, extremely excellent antireflection characteristics can be achieved.

D. Next layer

D-1. The first subsequent layer and the second subsequent layer

The first adhesive layer and the second adhesive layer may be composed of any appropriate adhesive or adhesive as long as the average linear expansion coefficient satisfies the relationship described in the above item A.

The subsequent agent preferably has transparency and optical isotropy. Any suitable one may be employed as the form of the adhesive. Specific examples thereof include an aqueous adhesive, a solvent-based adhesive, an emulsion-based adhesive, a solventless adhesive, an active energy ray-curable adhesive, and a thermosetting adhesive. Examples of the active energy ray-curable adhesive include an electron beam curing type adhesive, an ultraviolet curing type adhesive, and a visible light curing type adhesive. An aqueous adhesive and an active energy ray-curable adhesive can be preferably used.

Specific examples of the aqueous adhesive include an isocyanate-based adhesive, a polyvinyl alcohol-based adhesive, a gelatin-based adhesive, a vinyl-based latex, an aqueous polyurethane, and an aqueous polyester. It is preferably a polyvinyl alcohol-based adhesive such as polyvinyl alcohol or modified polyvinyl alcohol, and further preferably an adhesive having a polyvinyl alcohol having an ethyl oxime group as a main component. Such an adhesive is commercially available, and a specific example of a commercially available product is Manufactured by Nippon Synthetic Chemical Co., Ltd. (trade name "Gohsefimer Z").

Specific examples of the active energy ray-curable adhesive include a (meth)acrylate-based adhesive. Further, (meth) acrylate means acrylate and/or methacrylate. Examples of the curable component in the (meth)acrylate-based adhesive include a compound having a (meth)acryl fluorenyl group and a compound having a vinyl group. The compound having a (meth) acrylonitrile group is preferably an N-substituted amide group monomer represented by the following formula (1).

CH ₂ =C(R ¹ )-CONH _2-m -(XOR ² ) _m (1)

Here, R ¹ represents a hydrogen atom or a methyl group, X represents a -CH ₂ - group or a -CH ₂ CH ₂ - group, and R ² represents a -(CH ₂ ) _n -H group (where n is 0, 1 or 2) ), m means 1 or 2.

The (meth) acrylate-based adhesive may further contain a monomer having two or more carbon-carbon double bonds, preferably a polyfunctional (meth) acrylate monomer as a curable component. More preferably, the monomer having two or more carbon-carbon double bonds is hydrophobic. Further, the (meth) acrylate-based adhesive may contain a monofunctional (meth) acrylate having various aromatic rings and a hydroxyl group, a (meth) acrylate urethane, a polyester (meth) acrylate. Etc. as a hardening component.

The (meth) acrylate-based adhesive may also contain any suitable copolymerization component.

The details of the aqueous adhesive and the active energy ray-curable adhesive are described in, for example, [0057] to [0089] of JP-A-2011-81539. The description of this publication is incorporated herein by reference.

Another specific example of the active energy ray-curable adhesive is a photocationic curable adhesive mainly comprising an epoxy compound and a photoacid generator. As the epoxy compound which can be used, for example, the compounds described in [0031] to [0085] of JP-A-2010-145537 can be mentioned. Further, examples of the photoacid generator include compounds described in [0080] to [0095] of JP-A-2009-013316. The descriptions of these publications are incorporated herein by reference.

The adhesive contains any suitable adhesive polymer. From the viewpoint of easily obtaining a balance of adhesion properties as an adhesive polymer, a polymer having a Tg of 0 ° C or less (usually -100 ° C or more) is preferred. Among such polymers, a polyester polymer or a (meth)acrylic polymer can be preferably used.

As the polyester-based polymer, a saturated polyester or a copolyester of a polyhydric alcohol and a polyvalent carboxylic acid can be typically used. Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, hexamethylene glycol, neopentyl glycol, 1,2-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, and decamethylene. Alcohol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2-bis(4-hydroxyphenyl)propane, bis (4- A diol such as hydroxyphenyl) hydrazine. Examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, 2,5-naphthalene dicarboxylic acid, and 2,6-naphthalene. Dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid, diphenylcarboxylic acid, diphenoxyethane dicarboxylic acid, diphenylphosphonium carboxylic acid, stilbene dicarboxylic acid, etc. Aromatic dicarboxylic acid; 1,3-cyclopentane dicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, hexahydroterephthalic acid, hexahydroisophthalic acid Alicyclic dicarboxylic acid such as dicarboxylic acid; malonic acid, dimethylmalonic acid, succinic acid, 3,3-diethyl succinic acid, glutaric acid, 2,2-dimethylglutaric acid, Aliphatic dicarboxylic acids such as diacid, 2-methyladipate, trimethyladipate, pimelic acid, sebacic acid, dimer acid, sebacic acid, suberic acid, dodecane dicarboxylic acid . As the polyvalent carboxylic acid, two or more kinds of polyvalent carboxylic acids are often used, and for example, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid are used in combination.

The (meth)acrylic polymer usually contains, as a main component, an alkyl (meth)acrylate as a monomer unit. The alkyl (meth)acrylate constituting the main skeleton of the (meth)acrylic polymer may, for example, be a linear or branched alkyl group having 1 to 18 carbon atoms. These may be used alone or in combination. The average carbon number of the alkyl groups is preferably from 3 to 9. Further, an alkyl (meth)acrylate containing an aromatic ring such as phenoxyethyl (meth)acrylate or benzyl (meth)acrylate can be used. The alkyl (meth)acrylate containing an aromatic ring may be used by mixing a polymer obtained by polymerizing the above-exemplified (meth)acrylic polymer, or may be alkylated with the above (meth)acrylic acid. The ester is used in copolymerization. From the viewpoint of transparency, copolymerization is preferred.

For the purpose of improving the adhesion or the heat resistance, the (meth)acrylic polymer may be introduced into a polymerizable functional group (for example, an unsaturated double bond such as a (meth) acrylonitrile group or a vinyl group by copolymerization. One or more kinds of copolymerized monomers.

In the above (meth)acrylic polymer, any suitable copolymerized monomer other than the above copolymerized monomer may be introduced by copolymerization. The kind, the number, the copolymerization ratio, and the like of such a copolymerized monomer can be appropriately set depending on the purpose.

The (meth)acrylic polymer may be any of a random copolymer, a block copolymer, and a graft copolymer.

A crosslinking agent may be included in the adhesive. As the crosslinking agent, an organic crosslinking agent or A multifunctional metal chelate. Examples of the organic crosslinking agent include an isocyanate crosslinking agent, a peroxide crosslinking agent, an epoxy crosslinking agent, and an imide crosslinking agent. Polyfunctional metal chelates are those in which a polyvalent metal is covalently bonded or coordinated to an organic compound. Examples of the polyvalent metal atom include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, Ti, and the like. . Examples of the atom in the organic compound which is a covalent bond or a coordinate bond include an oxygen atom, and examples of the organic compound include an alkyl ester, an alcohol compound, a carboxylic acid compound, an ether compound, and a ketone compound. The crosslinking agent is preferably an isocyanate crosslinking agent or a peroxide crosslinking agent.

Examples of the isocyanate crosslinking agent include toluene diisocyanate, chlorophenyl diisocyanate, tetramethylene diisocyanate, benzodimethyl diisocyanate, diphenylmethane diisocyanate, and hydrogenated diphenylmethane diisocyanate. Isocyanate monomer, and isocyanate compound or isocyanurate compound, biuret type compound obtained by adding the isocyanate monomer and trimethylolpropane, etc., and further to polyether polyol or polyester A urethane prepolymer type isocyanate obtained by an addition reaction of an alcohol, an acrylic polyol, a polybutadiene polyol, or a polyisoprene polyol.

As the peroxide-type crosslinking agent, any suitable one can be used as long as the base polymer of the adhesive is crosslinked by generating a radical active species by heating or light irradiation. When the workability and stability are considered, the minute half-life temperature of the peroxide-type crosslinking agent is preferably from 80 ° C to 160 ° C, more preferably from 90 ° C to 140 ° C. Specific examples of the peroxide which can be used as the crosslinking agent include di(2-ethylhexyl)peroxydicarbonate (one-minute half-life temperature: 90.6 ° C), and di-dicarbonate dihydrate (4- Tributylcyclohexyl)ester (one minute half-life temperature: 92.1 ° C), dibutyl phthalate dihydrate (one minute half-life temperature: 92.4 ° C), perylene neodecanoate tert-butyl ester (one minute half-life temperature) : 103.5 ° C), perhexyl peroxypivalate (one-minute half-life temperature: 109.1 ° C), perbutyl pivalate peroxylate (one-minute half-life temperature: 110.3 ° C), dilaurin peroxide (one Minute half-life temperature: 116.4 ° C), di-n-octyl peroxide (one-minute half-life temperature: 117.4 ° C), peroxygen 1,2-,3,3-tetramethylbutyl 2-ethylhexanoate (one-minute half-life temperature: 124.3 ° C), bis(4-methylbenzhydryl) peroxide (one minute half-life temperature: 128.2) °C), benzoyl peroxide (one-minute half-life temperature: 130.0 ° C), isobutyl isobutyrate (one-minute half-life temperature: 136.1 ° C), 1, 1-two (third hexyl peroxide) Cyclohexane (one minute half-life temperature: 149.2 ° C).

A decane coupling agent may be added as an additive in the adhesive. Examples of the decane coupling agent include 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropylmethyldimethoxydecane, and 2-(3,4-epoxycyclohexyl). An anthracene compound having an epoxy structure such as ethyltrimethoxydecane; 3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N- An amine group-containing oxime compound such as (2-aminoethyl)-3-aminopropylmethyldimethoxydecane; 3-chloropropyltrimethoxydecane; trimethoxy group containing ethyl acetonitrile a (meth)acrylonitrile-based decane coupling agent such as decane, 3-propenyloxypropyltrimethoxydecane, 3-methylpropenyloxypropyltriethoxydecane or the like; 3-isocyanato C A decane coupling agent having an isocyanate group such as an ester group of triethoxy decane.

The details of the adhesive are described in, for example, [0023] to [0080] of JP-A-2012-247517. The description of this publication is incorporated herein by reference.

By adjusting the type and amount of the monomer component of the adhesive and the adhesive, the copolymerization ratio, the type of the crosslinking agent, the type, amount, and amount of the additive, an adhesive having a desired coefficient of linear expansion can be obtained. Adhesive. Therefore, the first adhesive layer and the second adhesive layer having the desired relationship of the linear expansion coefficient can be formed.

The thickness of the first adhesive layer 30 is preferably from 0.05 μm to 30 μm, more preferably from 0.5 μm to 20 μm. The thickness of the second adhesive layer 40 is preferably from 10 μm to 30 μm, more preferably from 12 μm to 20 μm.

D-2. Other layers

Others used to form the layers of the layers of the polarizing plate with the phase difference layer of the present invention The subsequent layer (not shown) may comprise any suitable adhesive or adhesive. Preferably, the average linear expansion coefficient of the other subsequent layers is smaller than the average linear expansion coefficient of the second subsequent layer.

E. 2nd phase difference layer

The second retardation layer 50 can have any appropriate optical characteristics depending on the purpose. In one embodiment, the second retardation layer may be a so-called positive C plate in which the refractive index characteristic shows a relationship of nz>nx=ny. By using the positive C plate as the second retardation layer, it is possible to satisfactorily prevent the reflection in the oblique direction, and it is possible to realize a wide viewing angle of the antireflection function. In this case, the phase difference Rth (550) in the thickness direction of the second retardation layer is preferably -50 nm to -300 nm, more preferably -70 nm to -250 nm, still more preferably -90 nm to -200 nm, and particularly preferably It is -100nm~-180nm. Here, "nx=ny" includes not only the case where nx and ny are strictly equal, but also the case where nx and ny are substantially equal. That is, the in-plane phase difference Re (550) of the second retardation layer may be less than 10 nm.

The second retardation layer having a refractive index characteristic of nz>nx=ny may be formed of any suitable material. The second retardation layer preferably contains a film containing a liquid crystal material fixed in a vertical alignment. The liquid crystal material (liquid crystal compound) which can be vertically aligned may be a liquid crystal monomer or a liquid crystal polymer. Specific examples of the liquid crystal compound and the method for forming the retardation layer include a liquid crystal compound described in [0020] to [0028] of JP-A-2002-333642, and a method of forming the retardation layer. In this case, the thickness of the second retardation layer is preferably 0.5 μm to 10 μm, more preferably 0.5 μm to 8 μm, still more preferably 0.5 μm to 5 μm.

F. Conductive layer or isotropic substrate with conductive layer

The conductive layer can be applied to any suitable substrate by any suitable film forming method (for example, vacuum evaporation, sputtering, CVD (chemical vapor deposition), ion plating, or spray). It is formed by forming a film of a metal oxide film. Examples of the metal oxide include indium oxide, tin oxide, zinc oxide, indium-tin composite oxide, tin-bismuth composite oxide, zinc-aluminum composite oxide, and indium-zinc composite oxide. among them, An indium-tin composite oxide (ITO) is preferred.

In the case where the conductive layer contains a metal oxide, the thickness of the conductive layer is preferably 50 nm or less, more preferably 35 nm or less. The lower limit of the thickness of the conductive layer is preferably 10 nm.

The conductive layer may be transferred from the substrate to the first retardation layer (or, in the case of the presence of the second retardation layer), and the conductive layer alone may be used as a constituent layer of the polarizing plate with the retardation layer, or The laminate with the substrate (the substrate with the conductive layer) is laminated on the first retardation layer (or, in the case of the second retardation layer). Preferably, the substrate is optically isotropic, and thus the conductive layer can be used as a polarizing plate with a phase difference layer as an isotropic substrate with a conductive layer.

As the optically isotropic substrate (isotropic substrate), any suitable isotropic substrate can be used. As a material constituting an isotropic substrate, for example, it can be mentioned A resin having no conjugated resin such as an olefin-based resin or a olefin-based resin, or a material having a cyclic structure such as a lactone ring or a quinodiimine ring in the main chain of the acrylic resin. When such a material is used, when an isotropic substrate is formed, the expression of the phase difference accompanying the alignment of the molecular chains can be suppressed to be small. The thickness of the isotropic substrate is preferably 50 μm or less, more preferably 35 μm or less. The lower limit of the thickness of the isotropic substrate is, for example, 20 μm.

The conductive layer and/or the conductive layer of the isotropic substrate with the conductive layer may be patterned as needed. The conductive portion and the insulating portion can be formed by patterning. As a result, an electrode can be formed. The electrode functions as a touch sensor electrode that senses contact with the touch panel. As the patterning method, any appropriate method can be employed. Specific examples of the patterning method include a wet etching method and a screen printing method.

G. Other

The retardation layer-attached polarizing plate according to the embodiment of the present invention may further include other retardation layers. The optical characteristics (for example, refractive index characteristics, in-plane phase difference, Nz coefficient, and photoelastic coefficient), thickness, arrangement position, and the like of the other retardation layer can be appropriately set depending on the purpose.

In practical applications, it is preferable to apply a release film to the surface of the second adhesive layer 40 until a polarizing plate with a retardation layer is used.

H. Image display device

The polarizing plate with the phase difference layer described in the above items A to G can be applied to an image display device. Accordingly, the present invention includes an image display apparatus using such a retardation layer-attached polarizing plate. Typical examples of the image display device include a liquid crystal display device and an organic EL display device. The image display device according to the embodiment of the present invention includes the polarizing plate with the phase difference layer described in the above items A to G on the viewing side. The polarizing plate with the retardation layer is laminated such that the retardation layer is on the side of the display cell (for example, the liquid crystal cell or the organic EL cell) (the polarizing element is on the viewing side).

[Examples]

Hereinafter, the present invention will be specifically described by examples, but the present invention is not limited by the examples. Furthermore, the measurement method of each characteristic is as follows.

(1) Thickness

The retardation layer (the alignment-cured layer of the liquid crystal compound) formed by coating was measured by the interference film thickness measurement method using MCPD2000 manufactured by Otsuka Electronics. For the other films, measurement was performed using a digital micrometer (KC-351C manufactured by Anritsu Co., Ltd.).

(2) Average linear expansion coefficient

Using a TMA (SS7100) manufactured by SII NanoTechnology, each of the adhesive layer forming solutions used in the examples and the comparative examples was formed into a film of about 100 μm, and the film was cut into about 6 mm square and placed on a sample stage, in accordance with JIS. K 7197 was subjected to TMA (compression expansion method) measurement. The measurement load is 19.6mN and the probe diameter is 3.5mm. The average linear expansion coefficient in the range was calculated from the data of the dimensional change obtained in the range of -150 ° C to 20 ° C under the condition of a heating rate of 5 ° C / min.

(3) Phase difference of the phase difference layer

By automatic birefringence measuring device (manufactured by Oji Scientific Instruments Co., Ltd., The dynamic birefringence meter KOBRA-WPR) measures the refractive indices nx, ny, and nz of the retardation layer used in the examples and the comparative examples. The measurement wavelength of the in-plane retardation Re was 450 nm and 550 nm, the measurement wavelength of the thickness direction retardation Rth was 550 nm, and the measurement temperature was 23 °C.

(4) Reworkability

Disassemble and remove the organic EL panel from the smart phone (Galaxy-S5) manufactured by Samsung Wireless. Then, the polarizing plates with the phase difference layers obtained in the examples and the comparative examples were cut and bonded in such a manner as to match the dimensions of the panels. The panel to which the polarizing plate with the retardation layer was attached was immersed in liquid nitrogen for 30 seconds, and then taken out, and it was confirmed whether or not the polarizing plate with the retardation layer was peeled off. For each of the examples and the comparative examples, 20 panels each having a polarizing plate with a phase difference layer attached thereto were produced and evaluated. The evaluation was performed on the basis of the following criteria.

Good: For all 20 panels, the polarizing plates with the retardation layer were well peeled off.

Poor: There is a polarizing plate with a phase difference layer that cannot be peeled off by at least one panel.

[Reference Example 1: Production of Polarizing Plate]

The long roll of a polyvinyl alcohol (PVA)-based resin film (manufactured by Kuraray, product name "PE3000") having a thickness of 30 μm was uniaxially stretched in the longitudinal direction by a roll extender so as to be 5.9 times in the longitudinal direction. At the same time, weaving, dyeing, cross-linking, and washing treatment were carried out, and finally, a drying treatment was carried out to prepare a polarizing element 1 having a thickness of 12 μm.

Specifically, the moisturizing treatment was carried out by using pure water at 20 ° C while extending to 2.2 times. Then, the dyeing treatment was carried out in an aqueous solution having an iodine concentration adjusted to a weight ratio of iodine to potassium iodide of 1:7 at 30 ° C, so that the monomer transmittance of the obtained polarizing element was 45.0%. 1.4 times. Further, the crosslinking treatment was carried out by a two-stage crosslinking treatment, and the first-stage crosslinking treatment was carried out while being treated at 40 ° C in an aqueous solution of boric acid and potassium iodide, and was extended to 1.2 times. The aqueous solution of the crosslinking treatment in the first stage had a boric acid content of 5.0% by weight and a potassium iodide content of 3.0% by weight. The second-stage crosslinking treatment was carried out while being treated at 65 ° C in an aqueous solution of boric acid and potassium iodide, and was extended to 1.6 times. The aqueous solution of the crosslinking treatment in the second stage had a boric acid content of 4.3% by weight and a potassium iodide content of 5.0% by weight. Further, the washing treatment was carried out in an aqueous solution of potassium iodide at 20 °C. The potassium iodide content of the aqueous solution of the washing treatment was set to 2.6% by weight. Finally, the drying treatment was carried out by drying at 70 ° C for 5 minutes to obtain a polarizing element 1.

a TAC film (product name: KC2UA, thickness: 25 μm, corresponding to the second protective layer) manufactured by Konica Minolta Co., Ltd. was bonded to both sides of the obtained polarizing element 1 via a polyvinyl alcohol-based adhesive. An HC-TAC film (thickness: 32 μm, corresponding to the first protective layer) having a hard coat layer (HC) formed by hard coating treatment on one side of the TAC film, thereby obtaining a first protective layer/polarizing element 1/first 2 polarizing plate 1 composed of a protective layer.

[Reference Example 2: Fabrication of a retardation film constituting a phase difference layer]

2-1. Preparation of polycarbonate resin film

26.2 parts by mass of isosorbide (ISB), 10,9 parts by mass of 9,9-[4-(2-hydroxyethoxy)phenyl]indole (BHEPF), 1,4-cyclohexanedimethanol (1,4) -CHDM) 10.7 parts by mass, 105.1 parts by mass of diphenyl carbonate (DPC), and 0.591 parts by mass of cesium carbonate (0.2% by mass aqueous solution) as a catalyst, respectively, were placed in a reaction vessel, and the reaction was carried out under a nitrogen atmosphere. In the first step, the temperature of the heat medium in the reaction vessel was set to 150 ° C, and the raw material was dissolved while stirring (about 15 minutes).

Then, the pressure in the reaction vessel was changed from normal pressure to 13.3 kPa, and the temperature of the heat medium in the reaction vessel was raised to 190 ° C for 1 hour, and the generated phenol was discharged to the outside of the reaction vessel.

The temperature in the reaction vessel was maintained at 190 ° C for 15 minutes. Thereafter, as a second step, the pressure in the reaction vessel was set to 6.67 kPa, and the temperature of the heat medium in the reaction vessel was raised to 230 ° C in 15 minutes to produce The phenol is discharged to the outside of the reaction vessel. Since the stirring torque of the stirrer is continuously increased, the temperature is raised to 250 ° C in 8 minutes, and in order to remove the generated phenol, the pressure in the reaction vessel is reduced to 0.200 kPa or less. To achieve a specific stirring torque Thereafter, the reaction was terminated, and the resulting reactant was extruded into water, followed by granulation to obtain a polycarbonate resin of BHEPF/ISB/1,4-CHDM = 47.4 mol% / 37.1 mol% / 15.5 mol%.

The polycarbonate resin obtained had a glass transition temperature of 136.6 ° C and a specific viscosity of 0.395 dL / g.

The obtained polycarbonate resin was vacuum dried at 80 ° C for 5 hours, and then used with a single-axis extruder (manufactured by Isuzu Chemical Co., Ltd., screw diameter 25 mm, cylinder set temperature: 220 ° C), T-die ( Width: 200 mm, set temperature: 220 ° C), a chill roll (set temperature: 120 ° C to 130 ° C), and a film forming apparatus of a coiler to produce a polycarbonate resin film having a thickness of 120 μm.

2-2. Production of retardation film

The obtained polycarbonate resin film was laterally stretched using a tenter stretching machine to obtain a retardation film having a thickness of 50 μm. At this time, the stretching ratio was 250%, and the stretching temperature was set to 137 ° C to 139 ° C.

The retardation film obtained had a Re (550) of 137 nm to 147 nm, a Re (450)/Re (550) of 0.89, an Nz coefficient of 1.21, and an alignment angle (direction of the slow phase axis) of 90° with respect to the longitudinal direction. This retardation film was used as the phase difference layer 1.

[Reference Example 3: Fabrication of Liquid Crystal Alignment Curing Layer constituting Phase Difference Layer]

10 g of a polymerizable liquid crystal (manufactured by BASF Corporation, trade name "Paliocolor LC242", which is represented by the following formula), and a photopolymerization initiator for the polymerizable liquid crystal compound (manufactured by BASF Corporation: trade name "IRGACURE") 907") 3 g was dissolved in 40 g of toluene to prepare a liquid crystal composition (coating liquid).

The surface treatment was carried out by rubbing the surface of a polyethylene terephthalate (PET) film (thickness: 38 μm) with a rubbing cloth. The conditions were as follows: the number of rubbing (number of rubbing rolls) was 1, the radius r of the rubbing rolls was 76.89 mm, the number of revolutions of the rubbing rolls nr was 1500 rpm, the film conveying speed v was 83 mm/sec, and the frictional strength RS And the amount of press-in M is five conditions (a) to (e) as shown in Table 1.

The direction of the alignment treatment is a direction of -75° with respect to the absorption axis direction of the polarizing element when viewed from the viewing side when bonded to the polarizing plate. The liquid crystal coating liquid was applied onto the alignment treatment surface by a bar coater, and dried by heating at 90 ° C for 2 minutes to align the liquid crystal compound. Under the conditions (a) to (c), the alignment state of the liquid crystal compound is very good. Under the conditions (d) and (e), slight disorder occurs in the alignment of the liquid crystal compound, but it is a level of no problem in practical use. The liquid crystal layer thus formed was irradiated with light of 1 mJ/cm ² with a metal halide lamp to cure the liquid crystal layer, whereby a retardation layer (liquid crystal alignment cured layer) 2 was formed on the PET film. The thickness of the retardation layer 2 was 2 μm, and the in-plane retardation Re (550) was 270 nm. Further, the phase difference layer 2 has a refractive index distribution of nx>ny=nz.

[Reference Example 4: Fabrication of Liquid Crystal Alignment Curing Layer constituting Phase Difference Layer]

The surface treatment was carried out by rubbing the surface of a polyethylene terephthalate (PET) film (thickness: 38 μm) with a rubbing cloth. The direction of the alignment treatment is a direction of -15° with respect to the absorption axis direction of the polarizing element when viewed from the viewing side when bonded to the polarizing plate. The liquid crystal coating liquid of the same manner as in Reference Example 3 was applied onto the alignment treatment surface, and the liquid crystal compound was aligned and hardened in the same manner as in Reference Example 3 to form a phase difference layer 3 on the PET film. Phase difference layer 3 The thickness was 1.2 μm, and the in-plane retardation Re (550) was 140 nm. Further, the phase difference layer 3 has a refractive index distribution of nx>ny=nz.

[Reference Example 5: Production of the next layer]

99 parts of butyl acrylate, 1.0 part of 4-hydroxybutyl acrylate and 0.3 parts of 2,2'-azobisisobutyronitrile and acetic acid B in a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer and a stirring device The esters are added together. The mixture in the reaction vessel was reacted at 60 ° C for 4 hours under a nitrogen stream, and then ethyl acetate was added to the reaction liquid to obtain a solution containing an acrylic polymer having a weight average molecular weight of 1.65 million (solid content concentration: 30%). ). 0.15 parts per 100 parts of the solid content of the acrylic polymer solution per ton of benzoic acid peroxide (manufactured by Nippon Oil & Fat Co., Ltd.: NYPER BO-Y), 0.1 part of trimethylolpropane benzene Methyl diisocyanate (Mitsui Takeda Chemical Co., Ltd.: TAKENATE D110N), and 0.2 part of a decane coupling agent (manufactured by Amika Chemical Co., Ltd.: A-100, a decane coupling agent containing an ethyl acetonitrile) to obtain an adhesive layer A solution for formation. The above-mentioned solution for forming a back layer was applied to a separator containing a polyester film surface-treated with a polyfluorene-based release agent, and heat-treated at 155 ° C for 3 minutes to obtain an adhesive layer A having a thickness of 15 μm.

[Reference Example 6: Production of the next layer]

A monomer mixture containing 99 parts of butyl acrylate and 1 part of 4-hydroxybutyl acrylate was added to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler. Further, 0.1 part of 2,2'-azobisisobutyronitrile as a polymerization initiator was added together with ethyl acetate to 100 parts of the monomer mixture (solid content), and nitrogen gas was introduced while slowly stirring. Nitrogen replacement was carried out, and then the temperature in the flask was maintained at around 60 ° C to carry out a polymerization reaction for 7 hours. Thereafter, ethyl acetate was added to the obtained reaction solution to prepare a solution of an acrylic polymer having a weight average molecular weight of 1.4 million (solid content concentration: 30%). 0.2 parts of trimethylpropylammonium bis(trifluoromethanesulfonyl) phthalimide (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared in an amount of 100 parts of the solid content of the obtained acrylic polymer solution. Further, 0.1 parts of trimethylolpropane phthalyl diisocyanate (manufactured by Mitsui Chemicals, Inc.: TAKENATE D110N), 0.3 parts of dibenzoyl peroxide, and γ-glycidoxypropyl methoxy decane (Shin-Etsu Chemical) were prepared. A solution for forming an adhesive layer was prepared by making 0.075 parts of KBM-403). Then, the solution for forming an adhesive layer is uniformly applied onto the surface of a polyethylene terephthalate film (separator) treated with a polyfluorene-based release agent by a spray coater, and The film was dried in an air circulating isothermal oven at 155 ° C for 2 minutes to form a back layer B having a thickness of 15 μm on the surface of the separator.

[Reference Example 7: Production of the next layer]

94.9 parts of butyl acrylate, 5 parts of acrylic acid, 0.1 part of 2-hydroxyethyl acrylate, and relative to the monomer (solid content) in a reaction vessel equipped with a cooling tube, a nitrogen gas introduction tube, a thermometer, and a stirring device 100 parts of 0.3 parts of benzamidine peroxide were added together with ethyl acetate. The mixture in the reaction vessel was reacted at 60 ° C for 7 hours under a nitrogen stream, and then ethyl acetate was added to the reaction solution to obtain a solution containing an acrylic polymer having a weight average molecular weight of 2.2 million (solid content concentration: 30 parts by weight) %). Formulated to 0.6 parts by weight of trimethylolpropane toluene diisocyanate (manufactured by Nippon Polyurethane Co., Ltd.: CORONATE L) and 0.075 parts of γ-glycidoxypropyl group per 100 parts of the solid content of the above acrylic polymer solution A solution for forming an adhesive layer was obtained by methoxymethoxydecane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-403). The solution for forming a subsequent layer was applied onto a separator containing a polyester film surface-treated with a polyfluorene-based release agent, and heat-treated at 155 ° C for 3 minutes to obtain an adhesive layer C having a thickness of 15 μm.

[Reference Example 8: Production of an adhesive constituting the adhesive layer]

Hydroxyethyl acrylamide as a monofunctional radically polymerizable compound (manufactured by Kohjin Co., Ltd., log P = -0.56, Tg of a homopolymer = 123 ° C) 10 parts and tetrahydrofurfuryl (meth) acrylate (Hitachi Chemical Co., Ltd.) Made by the company, logP=1.13, homopolymer Tg=45°C) 10 parts, tricyclodecane dimethanol diacrylate as a monofunctional radical polymerizable compound LIGHT ACRYLATE DCP-A, logP=3.05, homopolymer Tg=134°C), 80 parts, and IRGACURE 907 3 parts as a radical polymerization initiator and 3 parts of KAYACURE DETX-S And stirring at 50 ° C for 1 hour, an active energy ray hardening type adhesive (forming an adhesive for the subsequent layer D) was obtained.

[Example 1]

The surface of the second protective layer of the polarizing plate 1 and the retardation layer 1 are bonded via the bonding layer B so that the angle between the absorption axis of the polarizing element and the slow axis of the retardation layer is 45°, thereby obtaining a phase difference. Layer of polarizing plate. The adhesive layer 1 with the retardation layer was formed by bonding the adhesive layer A as the outermost layer to the phase difference layer of the obtained polarizing plate 1 with the retardation layer. The polarizing plate 1 with the phase difference layer obtained was evaluated for reworkability according to the above (4). As a result, the polarizing plate 1 with the retardation layer was peeled off favorably for the 20 panels produced. The results are shown in Table 2.

[Embodiment 2]

The polarizing plate 2 with the retardation layer was obtained in the same manner as in Example 1 except that the bonding layer 1 and the retardation layer 1 were bonded to each other using the bonding layer C and the bonding layer B was used as the outermost layer. The polarizing plate 2 with the phase difference layer obtained was subjected to reworkability evaluation according to the above (4). The results are shown in Table 2.

[Comparative Example 1]

A polarizing plate 3 with a retardation layer was obtained in the same manner as in Example 1 except that the bonding layer 1 and the retardation layer 1 were bonded to each other and the bonding layer C was used as the outermost layer. The polarizing plate 3 with the phase difference layer obtained was subjected to reworkability evaluation according to the above (4). The results are shown in Table 2.

[Comparative Example 2]

A cycloolefin-based retardation film A (manufactured by Kaneka Co., Ltd., product name "KUZ-Film #270", thickness 33 μm, Re (550) = 270 nm, Re (450) / Re (550) = 1.00, Nz coefficient = 1.00) And cycloolefin-based retardation film B (Kaneka company, product name "KUZ- Film #140", thickness 28 μm, Re (550) = 140 nm, Re (450) / Re (550) = 1.00, Nz coefficient = 1.00) The thickness is 60° by the angle formed by the respective slow phase axes. A 5 μm acrylic adhesive layer was bonded to prepare a retardation layer 4.

The second protective layer of the polarizing plate 1 and the phase difference layer 4 are formed at an angle of 15° between the absorption axis of the polarizing element and the slow axis of the retardation film A, and the absorption axis of the polarizing element and the retardation film B are delayed. The polarizing plate with the retardation layer was obtained by bonding the angle formed by the phase axis to 75° via the adhesive layer B. The adhesive layer 4 with the retardation layer was formed by bonding the adhesive layer C as the outermost layer to the phase difference layer of the obtained polarizing plate 1 with the retardation layer. The polarizing plate 4 with the phase difference layer obtained was evaluated for reworkability according to the above (4). The results are shown in Table 2.

[Example 3]

The second protective layer of the polarizing plate 1 and the retardation layer 2 are bonded via the active energy ray-curable adhesive (adjacent layer D) obtained in Reference Example 8, and two layers of the retardation layer 2 and the phase difference layer 3 are used. Except for this, a retardation plate 5 with a retardation layer was obtained in the same manner as in the first embodiment. Specifically, the active energy ray-curable adhesive is applied to the retardation layer 2 of the laminate of the PET film/phase difference layer 2 so that the thickness after curing is about 1.0 μm, and then the roll is applied. The machine is attached to the polarizing plate 1. Thereafter, the IR heater was used to heat the film from the retardation layer 2 side to 50 ° C, and the visible light rays (metal halide lamps in which gallium was enclosed) as active energy rays were irradiated from the retardation layer 2 side to cure the adhesive. As a result, the angle formed by the absorption axis of the polarizing element and the retardation axis of the phase difference layer 2 was 15°. Further, "Light Hammer 10" manufactured by Fusion UV Systems, Inc. was used as an active energy ray irradiation device, and a V bulb was used as a bulb. The peak illuminance was 1600 mW/cm ² and the cumulative irradiation amount was 1000 mJ/cm ² (wavelength: 380 nm to 440 nm). The illuminance of visible light was measured using a Sola-Check System manufactured by Solatell. Then, the PET film was peeled off, and the phase difference layer 3 was bonded to the peeling surface in the same manner as the phase difference layer 2. As a result, the angle formed by the absorption axis of the polarizing element and the retardation axis of the phase difference layer 3 was 75°. Further, the PET film on which the retardation layer 3 is formed is peeled off to obtain a polarizing plate having a retardation layer having a configuration of the polarizing plate/phase difference layer 2/phase difference layer 3. The adhesive layer A was attached as the outermost layer to the retardation layer 3 of the obtained polarizing plate with a retardation layer to form a polarizing plate 5 with a retardation layer.

The obtained polarizing plate 5 with the retardation layer was subjected to reworkability evaluation according to the above (4). The results are shown in Table 2.

[Comparative Example 3]

A polarizing plate 6 with a retardation layer was obtained in the same manner as in Example 1 except that the adhesion layer 1 and the retardation layer 1 were bonded to each other. The obtained polarizing plate 6 with the retardation layer was subjected to reworkability evaluation in accordance with the above (4). The results are shown in Table 2.

<evaluation>

As is clear from Table 2, the phase difference layer-attached polarizing plate of the embodiment of the present invention is excellent in reworkability at a low temperature using liquid nitrogen. Further, in the polarizing plate with the retardation layer of Comparative Example 1, if the film which cannot be reworked at a low temperature by manual peeling (a phase difference layer which is not peeled off from the display unit) is used, the film is broken and cannot be reworked. machining. another On the other hand, the polarizing plate with the retardation layer of Comparative Example 2 can be peeled off by hand without rupturing the film which cannot be reworked at a low temperature.

[Industrial availability]

The retardation layer-attached polarizing plate of the present invention can be preferably used for an image display device such as a liquid crystal display device and an organic EL display device.

10‧‧‧Polar plate

11‧‧‧Polarized components

12‧‧‧1st protective layer

13‧‧‧2nd protective layer

20‧‧‧ phase difference layer

30‧‧‧1st layer

40‧‧‧2nd layer

100‧‧‧Polarizer with phase difference layer

Claims (8)

A polarizing plate with a retardation layer, comprising: a polarizing plate comprising a polarizing element and a protective layer on at least one side of the polarizing element; a phase difference layer; a first bonding layer, the polarizing plate and the phase And the second subsequent layer is disposed as an outermost layer of the retardation layer opposite to the polarizing plate, and an average of the second bonding layer when the ambient temperature is changed from -150 ° C to 20 ° C The coefficient of linear expansion is 38.0 (×10 ^-5 /°C) or more, and is larger than the average linear expansion coefficient of the first subsequent layer when the ambient temperature is changed from -150 ° C to 20 ° C. The polarizing plate of the phase difference layer of claim 1, wherein the total thickness of each of the layers other than the second adhesive layer is 140 μm or less. The polarizing plate of the phase difference layer of claim 1, wherein the retardation layer comprises a polycarbonate resin film. A polarizing plate with a phase difference layer as claimed in claim 3, which further has another phase difference layer on the outer side of the phase difference layer. The polarizing plate of the phase difference layer of claim 1, wherein the phase difference layer is an alignment solidified layer of a liquid crystal compound. The polarizing plate of the phase difference layer of claim 5, wherein the retardation layer has a laminated structure of a alignment hardening layer of the first liquid crystal compound and a alignment hardening layer of the second liquid crystal compound. The polarizing plate of the phase difference layer of claim 1 further comprising a conductive layer or an isotropic substrate with a conductive layer on the outer side of the phase difference layer. An image display device comprising a polarizing plate with a phase difference layer as claimed in claim 1.