JP6681934B2 - Polarizing plate and organic EL panel - Google Patents

Description

  The present invention relates to a polarizing plate and an organic EL panel.

  In recent years, with the widespread use of thin displays, displays equipped with organic EL panels have been proposed. Since the organic EL panel has a highly reflective metal layer, problems such as external light reflection and background reflection are likely to occur. Therefore, it is known that a circularly polarizing plate is provided on the viewing side to prevent these problems. As a general circularly polarizing plate, a retardation film (typically a λ / 4 plate) represented by a cycloolefin (COP) resin film is used, and its slow axis is about the absorption axis of the polarizer. It is known that the layers are laminated so as to form an angle of 45 °. It is known that a retardation film made of a COP-based resin has a so-called flat wavelength dispersion characteristic in which a retardation value does not depend on the wavelength of measurement light and is substantially constant. When a circularly polarizing plate including a retardation film having such a flat wavelength dispersion characteristic is used for an organic EL panel, there is a problem that an excellent reflective hue cannot be obtained.

  In order to solve the above problems, a circularly polarizing plate including a retardation film having a so-called inverse dispersion wavelength dependency (inverse dispersion wavelength characteristic) in which a retardation value increases according to the wavelength of measurement light is proposed. (For example, Patent Document 1). When such a circularly polarizing plate is used in an organic EL panel, the reflection of external light and the reflection hue in the front direction can be greatly improved. However, when the panel is viewed from an oblique direction, a hue different from the hue in the front direction is obtained, and this hue difference poses a serious problem. It has also been confirmed that the display characteristics of the panel change over time.

Japanese Patent No. 3325560

  The present invention has been made to solve the above conventional problems, and a main object thereof is to provide a polarizing plate that suppresses changes in excellent viewing angle characteristics and display characteristics.

（上記一般式（１）中、Ｒ_１〜Ｒ_４はそれぞれ独立に、水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、置換若しくは無置換の炭素数６〜炭素数２０のシクロアルキル基、または、置換若しくは無置換の炭素数６〜炭素数２０のアリール基を表し、Ｘは置換若しくは無置換の炭素数２〜炭素数１０のアルキレン基、置換若しくは無置換の炭素数６〜炭素数２０のシクロアルキレン基、または、置換若しくは無置換の炭素数６〜炭素数２０のアリーレン基を表し、ｍ及びｎはそれぞれ独立に０〜５の整数である。）
好ましい実施形態においては、上記第１の位相差層が、下記一般式（２）で表されるジヒドロキシ化合物に由来する構造単位を含むポリカーボネート樹脂で形成される。

好ましい実施形態においては、上記第１の位相差層が、下記一般式（５）で表されるジヒドロキシ化合物に由来する構造単位を含むポリカーボネート樹脂で形成される。

（上記一般式（５）中、Ｒ_７は置換若しくは無置換の炭素数２〜炭素数１０のアルキレン基を示し、ｐは２から１００の整数である。）
好ましい実施形態においては、上記第１の位相差層が斜め延伸して得られた位相差フィルムである。
本発明の別の局面によれば、有機ＥＬパネルが提供される。この有機ＥＬパネルは、上記偏光板を備える。 The polarizing plate of the present invention is used for an organic EL panel, and includes a polarizer, a first retardation layer, and a second retardation layer, and the first retardation layer has a refraction of nx> ny = nz. Showing a refractive index characteristic and satisfying the relation of Re (450) <Re (550), the second retardation layer showing a refractive index characteristic of nz> nx ≧ ny, and the absorption axis of the polarizer and the first The angle θ formed by the retardation layer and the slow axis of the retardation layer satisfies the relation of 35 ° ≦ θ ≦ 55 °, and Re (550 of the laminate of the first retardation layer and the second retardation layer is satisfied. ) Is 120 nm to 160 nm, Rth (550) is 40 nm to 100 nm, and the water absorption of the first retardation layer is 3% or less.
In a preferred embodiment, an optically anisotropic layer is not included between the polarizer and the first retardation layer or the second retardation layer.
In a preferred embodiment, the first retardation layer is formed of a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following general formula (1).

(In the general formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted 6 to 20 carbon atoms. Or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, X is a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, a substituted or unsubstituted carbon number A cycloalkylene group having 6 to 20 carbon atoms or a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, m and n are each independently an integer of 0 to 5.)
In a preferred embodiment, the first retardation layer is formed of a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following general formula (2).

In a preferred embodiment, the first retardation layer is formed of a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following general formula (5).

(In the general formula (5), R ₇ represents a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, and p is an integer of 2 to 100.)
In a preferred embodiment, the first retardation layer is a retardation film obtained by oblique stretching.
According to another aspect of the present invention, an organic EL panel is provided. This organic EL panel includes the above polarizing plate.

  According to the present invention, by using the first retardation layer and the second retardation layer satisfying the above optical characteristics and water absorption, the viewing angle characteristics are improved and the change in display characteristics is suppressed. can do.

(A) is a schematic sectional view of a polarizing plate according to a preferred embodiment of the present invention, and (b) is a schematic sectional view of a polarizing plate according to another preferred embodiment of the present invention.

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

(Definition of terms and symbols)
The 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 maximum (that is, the slow axis direction), and “ny” is the direction in the plane that is orthogonal to the slow axis (that is, the fast axis direction). , And "nz" is the refractive index in the thickness direction.
(2) In-plane retardation (Re)
“Re (550)” is an in-plane retardation measured with light having a wavelength of 550 nm at 23 ° C. Re (550) is calculated | required by Formula: Re = (nx-ny) * d, when the thickness of a layer (film) is set to d (nm). “Re (450)” is an in-plane retardation measured with light having a wavelength of 450 nm at 23 ° C.
(3) Phase difference in the thickness direction (Rth)
“Rth (550)” is the phase difference in the thickness direction measured with light having a wavelength of 550 nm at 23 ° C. Rth (550) is calculated | required by Formula: Rth = (nx-nz) * d, when the thickness of a layer (film) is set to d (nm). “Rth (450)” is a phase difference in the thickness direction measured with light having a wavelength of 450 nm at 23 ° C.
(4) Nz coefficient The Nz coefficient is calculated by Nz = Rth / Re.

A. Polarizing Plate The polarizing plate of the present invention includes a polarizer, a first retardation layer, and a second retardation layer, and the first retardation layer and the second retardation layer are laminated on one side of the polarizer. ing. Preferably, the polarizing plate does not include an optically anisotropic layer (for example, a liquid crystal layer or a retardation film) between the polarizer and the first retardation layer or the second retardation layer. Hereinafter, a specific example will be described.

  FIG. 1A is a schematic sectional view of a polarizing plate according to a preferred embodiment of the present invention. The polarizing plate 100 of the present embodiment includes a polarizer 10, a protective film 20 disposed on one side of the polarizer 10, a first retardation layer 30 and a second position disposed on the other side of the polarizer 10. And a phase difference layer 40. In the illustrated example, the first retardation layer 30 is arranged closer to the polarizer 10 side than the second retardation layer 40, but the second retardation layer 40 is arranged closer to the polarizer 10 side. May be. In the present embodiment, the first retardation layer 30 (second retardation layer 40) can also function as a protective layer for the polarizer 10. In addition, since the polarizer and the first retardation layer (second retardation layer) are directly bonded to each other in this manner, a more excellent reflective hue (particularly, viewing angle characteristic) is achieved, and display characteristics are improved. Can be suppressed.

  FIG. 1B is a schematic sectional view of a polarizing plate according to another preferred embodiment of the present invention. The polarizing plate 100 ′ includes a polarizer 10, a first protective film 21 arranged on one side of the polarizer 10, a first retardation layer 30 and a second position arranged on the other side of the polarizer 10. The phase difference layer 40 and the second protective film 22 arranged between the polarizer 10 and the first phase difference layer 30 are provided. Preferably, the second protective film 22 is optically isotropic. Since the second protective film is optically isotropic, it is possible to achieve a more excellent reflective hue (particularly, viewing angle characteristics). In the illustrated example, the first retardation layer 30 is arranged so as to be closer to the polarizer 10 side than the second retardation layer 40, but the second retardation layer 40 is closer to the polarizer 10 side. It may be arranged.

  The first retardation layer 30 has a refractive index characteristic of nx> ny ≧ nz and has a slow axis. The polarizer 10 and the first retardation layer 30 are laminated such that the absorption axis of the polarizer 10 and the slow axis of the first retardation layer 30 form a predetermined angle. The angle θ formed by the absorption axis of the polarizer 10 and the slow axis of the first retardation layer 30 preferably satisfies the relationship of 35 ° ≦ θ ≦ 55 °, more preferably 38 ° ≦ θ ≦ 52 °, More preferably, 39 ° ≦ θ ≦ 51 °. If the ratio is out of the above range, the front reflectance increases, and the antireflection function of the polarizing plate cannot be sufficiently obtained.

A-1. Polarizer Any appropriate polarizer can be adopted as the above-mentioned polarizer. Specific examples include hydrophilic polymer films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and ethylene / vinyl acetate copolymer partially saponified films, and dichroic substances such as iodine and dichroic dyes. Examples of the polyene-oriented film include those subjected to dyeing treatment and stretching treatment with polyvinyl alcohol, dehydrated polyvinyl alcohol and dehydrochlorinated polyvinyl chloride. Preferably, a polarizer obtained by dyeing a polyvinyl alcohol film with iodine and uniaxially stretching it is used because it has excellent optical properties.

  The dyeing with iodine is performed, for example, by immersing a polyvinyl alcohol film in an iodine aqueous solution. The stretching ratio of the uniaxial stretching is preferably 3 to 7 times. Stretching may be performed after the dyeing treatment or may be performed while dyeing. Further, it may be stretched and then dyed. If necessary, the polyvinyl alcohol film is subjected to swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like. For example, by immersing a polyvinyl alcohol-based film in water and washing it before dyeing, not only can the stains and antiblocking agents on the surface of the polyvinyl alcohol-based film be washed, but also the polyvinyl alcohol-based film can be swollen and dyed. It is possible to prevent unevenness.

  The thickness of the polarizer is typically about 1 μm to 80 μm.

A-2. First Retardation Layer As described above, the first retardation layer has a refractive index characteristic of nx> ny ≧ nz. The in-plane retardation Re (550) of the first retardation layer is preferably 80 nm to 200 nm, more preferably 100 nm to 180 nm, still more preferably 110 nm to 170 nm.

  The first retardation layer exhibits so-called inverse dispersion wavelength dependency. Specifically, the in-plane retardation satisfies the relationship of Re (450) <Re (550). By satisfying such a relationship, an excellent reflective hue can be achieved. Re (450) / Re (550) is preferably 0.8 or more and less than 1, and more preferably 0.8 or more and 0.95 or less.

  The Nz coefficient of the first retardation layer is preferably 1 to 3, more preferably 1 to 2.5, further preferably 1 to 1.5, and particularly preferably 1 to 1.3. By satisfying such a relationship, a more excellent reflective hue can be achieved.

  The first phase difference layer has a water absorption of 3% or less, preferably 2.5% or less, more preferably 2% or less. By satisfying such a water absorption rate, it is possible to suppress a change with time in display characteristics. The water absorption rate can be determined according to JIS K 7209.

  The first retardation layer is typically a retardation film formed of any appropriate resin. A polycarbonate resin is preferably used as the resin forming the retardation film.

  In a preferred embodiment, the polycarbonate resin has a structural unit derived from a dihydroxy compound represented by the following general formula (1), a structural unit derived from a dihydroxy compound represented by the following general formula (2), and A dihydroxy compound represented by the general formula (3), a dihydroxy compound represented by the following general formula (4), a dihydroxy compound represented by the following general formula (5), and a dihydroxy compound represented by the following general formula (6) And a structural unit derived from one or more dihydroxy compounds selected from the group consisting of:

（上記一般式（１）中、Ｒ_１〜Ｒ_４はそれぞれ独立に、水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、置換若しくは無置換の炭素数６〜炭素数２０のシクロアルキル基、または、置換若しくは無置換の炭素数６〜炭素数２０のアリール基を表し、Ｘは置換若しくは無置換の炭素数２〜炭素数１０のアルキレン基、置換若しくは無置換の炭素数６〜炭素数２０のシクロアルキレン基、または、置換若しくは無置換の炭素数６〜炭素数２０のアリーレン基を表し、ｍ及びｎはそれぞれ独立に０〜５の整数である。）

(In the general formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted 6 to 20 carbon atoms. Or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, X is a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, a substituted or unsubstituted carbon number A cycloalkylene group having 6 to 20 carbon atoms or a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, m and n are each independently an integer of 0 to 5.)

（上記一般式（３）中、Ｒ_５は炭素数４から炭素数２０の置換若しくは無置換の単環構造のシクロアルキレン基を示す。）

(In the general formula (3), R ₅ represents a cycloalkylene group having a substituted or unsubstituted monocyclic structure having 4 to 20 carbon atoms.)

（上記一般式（４）中、Ｒ_６は炭素数４から炭素数２０の置換若しくは無置換の単環構造のシクロアルキレン基を示す。）

(In the general formula (4), R ₆ represents a cycloalkylene group having a substituted or unsubstituted monocyclic structure having 4 to 20 carbon atoms.)

（上記一般式（５）中、Ｒ_７は置換若しくは無置換の炭素数２〜炭素数１０のアルキレン基を示し、ｐは２から１００の整数である。）

(In the general formula (5), R ₇ represents a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, and p is an integer of 2 to 100.)

（上記一般式（６）中、Ｒ_１１は炭素数２から炭素数２０のアルキル基又は下記式（７）に示す基を表す。）

(In the general formula (6), R ₁₁ represents an alkyl group having 2 to 20 carbon atoms or a group represented by the following formula (7).)

<Dihydroxy compound represented by the general formula (1)>
Specific examples of the dihydroxy compound represented by the general formula (1) include 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9-bis (4-hydroxy-3-ethylphenyl) fluorene, 9,9-bis (4-hydroxy-3-n-propylphenyl) fluorene, 9,9-bis (4-hydroxy-3-isopropylphenyl) ) Fluorene, 9,9-bis (4-hydroxy-3-n-butylphenyl) fluorene, 9,9-bis (4-hydroxy-3-sec-butylphenyl) fluorene, 9,9-bis (4-hydroxy) -3-Tert-propylphenyl) fluorene, 9,9-bis (4-hydroxy-3-cyclohexylphenyl) fluorene, 9,9-bi (4-Hydroxy-3-phenylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-methylphenyl) Fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-isopropylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-isobutylphenyl) fluorene, 9,9- Bis (4- (2-hydroxyethoxy) -3-tert-butylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-cyclohexylphenyl) fluorene, 9,9-bis (4- (2-Hydroxyethoxy) -3-phenylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3 5-dimethylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-tert-butyl-6-methylphenyl) fluorene, 9,9-bis (4- (3-hydroxy-2, Examples thereof include 2-dimethylpropoxy) phenyl) fluorene, and preferably 9,9-bis (4-hydroxy-3-methylphenyl) fluorene and 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene. , 9,9-bis (4- (2-hydroxyethoxy) -3-methylphenyl) fluorene, and particularly preferably 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene.

<Dihydroxy compound represented by the general formula (2)>
Examples of the dihydroxy compound represented by the general formula (2) include isosorbide, isomannide and isoidide which are stereoisomeric. These may be used alone or in combination of two or more. Among these dihydroxy compounds, isosorbide obtained by dehydration condensation of sorbitol produced from various starches, which are abundant as resources and are easily available, is easy to obtain and produce, optical properties, and moldability. Is most preferable from the viewpoint of.

<Dihydroxy compound represented by the general formula (3)>
Examples of the dihydroxy compound represented by the general formula (3) include compounds containing a cycloalkylene group having a monocyclic structure (alicyclic dihydroxy compound). By having a monocyclic structure, it is possible to improve the toughness when the obtained polycarbonate resin is used as a film. Typical examples of the alicyclic dihydroxy compound include compounds having a 5-membered ring structure or a 6-membered ring structure. By having a 5-membered ring structure or a 6-membered ring structure, the heat resistance of the obtained polycarbonate resin can be increased. The 6-membered ring structure may be fixed in a chair shape or a boat shape by a covalent bond. Specifically, 1,2-cyclopentanediol, 1,3-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 2-methyl-1,4- Cyclohexanediol etc. are mentioned. The dihydroxy compound represented by the general formula (3) may be used alone or in combination of two or more kinds.

<Dihydroxy Compound Represented by General Formula (4)>
Examples of the dihydroxy compound represented by the general formula (4) include compounds containing a cycloalkylene group having a monocyclic structure (alicyclic dihydroxy compound). By having a monocyclic structure, it is possible to improve the toughness when the obtained polycarbonate resin is used as a film. As a typical example of the alicyclic dihydroxy compound, R ₆ in the general formula (4) is represented by the following general formula (Ia) (in the formula, R ³ is a hydrogen atom, or a substituted or unsubstituted carbon number 1 to carbon number). And represents various alkyl isomers of 12). Specific preferred examples of such isomers include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol and 1,4-cyclohexanedimethanol. These are easily available and have excellent handleability. The dihydroxy compound represented by the general formula (4) may be used alone or in combination of two or more kinds.

  The compounds exemplified above with respect to the dihydroxy compounds represented by the general formulas (3) and (4) are examples of alicyclic dihydroxy compounds that can be used, and the compounds are not limited thereto.

<Dihydroxy compound represented by the general formula (5)>
Specific examples of the dihydroxy compound represented by the general formula (5) include diethylene glycol, triethylene glycol, polyethylene glycol (molecular weight 150 to 2000).

<Dihydroxy compound represented by the general formula (6)>
Specific examples of the dihydroxy compound represented by the general formula (6) include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, and spiroglycol represented by the following formula (8). Among these, propylene glycol, 1,4-butanediol, and spiroglycol are preferable.

  Structural unit derived from dihydroxy compound represented by the general formula (3), structural unit derived from dihydroxy compound represented by the general formula (4), derived from dihydroxy compound represented by the general formula (5) Of the structural unit derived from the dihydroxy compound represented by the general formula (6) and the structural unit derived from the dihydroxy compound represented by the general formula (4) and / or the general formula (5) It preferably contains a structural unit derived from the dihydroxy compound represented by, and more preferably contains a structural unit derived from the dihydroxy compound represented by the general formula (5). By containing the structural unit derived from the dihydroxy compound represented by the general formula (5), the stretchability can be improved.

The polycarbonate resin of this embodiment may further contain a structural unit derived from another dihydroxy compound.
<Other dihydroxy compounds>
Examples of other dihydroxy compounds include bisphenols. Examples of the bisphenols include 2,2-bis (4-hydroxyphenyl) propane [= bisphenol A], 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis ( 4-hydroxy-3,5-diethylphenyl) propane, 2,2-bis (4-hydroxy- (3,5-diphenyl) phenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) ) Propane, 2,2-bis (4-hydroxyphenyl) pentane, 2,4'-dihydroxy-diphenylmethane, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-5-nitrophenyl) methane, 1,1 -Bis (4-hydroxyphenyl) ethane, 3,3-bis (4-hydroxyphenyl) pentane, 1,1-bis (4-hydr) Roxyphenyl) cyclohexane, bis (4-hydroxyphenyl) sulfone, 2,4′-dihydroxydiphenylsulfone, bis (4-hydroxyphenyl) sulfide, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3 Examples include'-dichlorodiphenyl ether, 4,4'-dihydroxy-2,5-diethoxydiphenyl ether and the like.

  In the polycarbonate resin, the structural unit derived from the dihydroxy compound represented by the general formula (1) is 18 mol% or more, preferably 20 mol% or more, more preferably 25 mol% or more. If the structural unit is too small, the wavelength dependence of inverse dispersion may not be obtained.

  The dihydroxy compound represented by the general formula (3), the dihydroxy compound represented by the general formula (4), the dihydroxy compound represented by the general formula (5), and the dihydroxy compound represented by the general formula (6). The structural unit derived from one or more dihydroxy compounds selected from the group consisting of compounds is preferably 25 mol% or more, more preferably 30 mol% or more, further preferably 35 mol% or more in the polycarbonate resin. Is. If the structural unit is excessively small, the toughness of the film may be poor.

  The glass transition temperature of the polycarbonate resin is preferably 110 ° C. or higher and 150 ° C. or lower, and more preferably 120 ° C. or higher and 140 ° C. or lower. If the glass transition temperature is excessively low, the heat resistance tends to be poor, dimensional change may occur after film formation, and the image quality of the obtained organic EL panel may be deteriorated. If the glass transition temperature is excessively high, the molding stability during film molding may be deteriorated, and the transparency of the film may be impaired. The glass transition temperature is determined according to JIS K 7121 (1987).

  The molecular weight of the polycarbonate resin can be represented by reduced viscosity. The reduced viscosity is measured using a Ubbelohde viscosity tube at a temperature of 20.0 ° C. ± 0.1 ° C. by precisely adjusting the polycarbonate concentration to 0.6 g / dL using methylene chloride as a solvent. The lower limit of the reduced viscosity is usually preferably 0.30 dL / g, more preferably 0.35 dL / g or more. The upper limit of the reduced viscosity is usually preferably 1.20 dL / g, more preferably 1.00 dL / g, further preferably 0.80 dL / g. If the reduced viscosity is smaller than the lower limit, there may occur a problem that the mechanical strength of the molded product becomes small. On the other hand, when the reduced viscosity is higher than the upper limit value, the fluidity at the time of molding may be lowered, and the productivity and the moldability may be lowered.

  The retardation film is typically produced by stretching a resin film in at least one direction.

  Any appropriate method can be adopted as the method for forming the resin film. For example, a melt extrusion method (for example, T-die molding method), a cast coating method (for example, a casting method), a calendar molding method, a hot pressing method, a coextrusion method, a comelting method, a multi-layer extrusion method, an inflation molding method and the like can be mentioned. To be Preferably, a T-die molding method, a casting method and an inflation molding method are used.

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

  For the above stretching, any appropriate stretching method and stretching conditions (for example, stretching temperature, stretching ratio, stretching direction) can be adopted. Specifically, various stretching methods such as free-end stretching, fixed-end stretching, free-end contraction, and fixed-end contraction can be used alone or simultaneously or sequentially. The stretching direction can also be performed in various directions and dimensions such as a horizontal direction, a vertical direction, a thickness direction, and a diagonal direction. The stretching temperature is preferably Tg-30 ° C to Tg + 60 ° C, more preferably Tg-10 ° C to Tg + 50 ° C, with respect to the glass transition temperature (Tg) of the resin film.

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

  In one embodiment, the retardation film is produced by uniaxially stretching or fixed-end uniaxially stretching a resin film. A specific example of the fixed-end uniaxial stretching is a method of stretching the resin film in the width direction (transverse direction) while running the resin film in the longitudinal direction. The draw ratio is preferably 1.1 times to 3.5 times.

  In another embodiment, the retardation film is produced by continuously stretching a long resin film in the direction of an angle θ with respect to the longitudinal direction. By adopting oblique stretching, a long stretched film having an orientation angle of θ with respect to the longitudinal direction of the film (slow axis in the direction of angle θ) can be obtained, and for example, when laminated with a polarizer. Roll-to-roll is possible, and the manufacturing process can be simplified.

  As a stretching machine used for oblique stretching, for example, a tenter-type stretching machine capable of applying a feeding force, a pulling force, or a pulling force at different speeds in right and left directions in the horizontal and / or vertical directions is exemplified. Examples of the tenter type stretching machine include a horizontal uniaxial stretching machine and a simultaneous biaxial stretching machine, but any appropriate stretching machine may be used as long as a long resin film can be continuously stretched obliquely.

  The thickness of the retardation film (stretched film) is preferably 20 μm to 100 μm, more preferably 30 μm to 80 μm, and further preferably 30 μm to 65 μm.

A-3. Second Retardation Layer As described above, the second retardation layer 40 has a refractive index characteristic of nz> nx ≧ ny. The retardation Rth (550) in the thickness direction of the second retardation layer is preferably -260 nm to -10 nm, more preferably -230 nm to -15 nm, and further preferably -215 nm to -20 nm.

  In one embodiment, the second retardation layer has a refractive index of nx = ny. Here, “nx = ny” includes not only the case where nx and ny are exactly equal but also the case where nx and ny are substantially equal. Specifically, it means that Re (550) is less than 10 nm. In another embodiment, the second retardation layer has a refractive index of nx> ny. In this case, the in-plane retardation Re (550) of the second retardation layer is preferably 10 to 150, more preferably 10 to 80.

  The second retardation layer may be formed of any appropriate material. A liquid crystal layer fixed in homeotropic alignment is preferred. The liquid crystal material (liquid crystal compound) capable of homeotropic alignment may be a liquid crystal monomer or a liquid crystal polymer. Specific examples of the liquid crystal compound and the method for forming the liquid crystal layer include the liquid crystal compounds and the formation methods described in [0020] to [0042] of JP-A-2002-333642. In this case, the thickness is preferably 0.1 μm to 5 μm, more preferably 0.2 μm to 3 μm.

  As another preferred specific example, the second retardation layer may be a retardation film formed of a fumaric acid diester resin described in JP 2012-32784 A. In this case, the thickness is preferably 5 μm to 50 μm, more preferably 10 μm to 35 μm.

A-4. Laminated body The in-plane retardation Re (550) of the laminated body of the first retardation layer and the second retardation layer is 120 nm to 160 nm, preferably 130 nm to 150 nm. The phase difference Rth (550) in the thickness direction of the laminate is 40 nm to 100 nm, preferably 60 nm to 80 nm. By setting the optical characteristics of the laminated body in this way, it is possible to improve the viewing angle characteristics and suppress changes in display characteristics. The laminate is obtained by laminating the first retardation layer and the second retardation layer via any appropriate pressure-sensitive adhesive layer or adhesive layer.

A-5. Protective Film The protective film is formed of any suitable film that can be used as a protective layer of a polarizer. Specific examples of the material serving as the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyester resins, polyvinyl alcohol resins, polycarbonate resins, polyamide resins, polyimide resins, polyether sulfone resins, and polysulfone resins. , Polystyrene-based, polynorbornene-based, polyolefin-based, (meth) acrylic-based, acetate-based transparent resins and the like. Further, a thermosetting resin such as a (meth) acrylic resin, a urethane resin, a (meth) acrylic urethane resin, an epoxy resin, a silicone resin, or an ultraviolet curable resin can be used. In addition to these, for example, a glassy polymer such as a siloxane polymer may be used. Further, a polymer film described in JP-A-2001-343529 (WO 01/37007) can also be used. As a material of the 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 a side chain And, for example, a resin composition having an alternating copolymer of isobutene and N-methylmaleimide and an acrylonitrile-styrene copolymer. The polymer film can be, for example, an extruded product of the resin composition.

  The (meth) acrylic resin has a Tg (glass transition temperature) of preferably 115 ° C. or higher, more preferably 120 ° C. or higher, further preferably 125 ° C. or higher, and particularly preferably 130 ° C. or higher. This is because it can have excellent durability. The upper limit of Tg of the (meth) acrylic resin is not particularly limited, but is preferably 170 ° C. or lower from the viewpoint of moldability and the like.

As the (meth) acrylic resin, any appropriate (meth) acrylic resin can be adopted as long as the effects of the present invention are not impaired. For example, poly (meth) acrylic acid ester such as poly (methyl methacrylate), methyl methacrylate- (meth) acrylic acid copolymer, methyl methacrylate- (meth) acrylic acid ester copolymer, methyl methacrylate-acrylic acid ester -(Meth) acrylic acid copolymer, methyl (meth) acrylate-styrene copolymer (MS resin etc.), polymer having alicyclic hydrocarbon group (for example, methyl methacrylate-cyclohexyl methacrylate copolymer) , Methyl methacrylate- (meth) acrylic acid norbornyl copolymer and the like). Preferably, C _1-6 alkyl poly (meth) acrylate such as methyl poly (meth) acrylate is used. More preferably, a methyl methacrylate resin containing methyl methacrylate as a main component (50 to 100% by weight, preferably 70 to 100% by weight) is used.

  Specific examples of the (meth) acrylic resin include, for example, Acrypet VH and Acrypet VRL20A manufactured by Mitsubishi Rayon Co., Ltd., and a (meth) acrylic resin having a ring structure in the molecule described in JP-A-2004-70296. Resins, and high Tg (meth) acrylic resins obtained by intramolecular crosslinking or intramolecular cyclization reaction.

  As the (meth) acrylic resin, a (meth) acrylic resin having a lactone ring structure is particularly preferable because it has high heat resistance, high transparency, and high mechanical strength.

  Examples of the (meth) acrylic resin having the lactone ring structure include JP-A-2000-230016, JP-A-2001-151814, JP-A-2002-120326, JP-A-2002-254544, and JP-A-2005-2005. And a (meth) acrylic resin having a lactone ring structure described in JP-A-146084.

  The (meth) acrylic resin having a lactone ring structure has a mass average molecular weight (sometimes referred to as a weight average molecular weight) of preferably 1,000 to 2,000,000, more preferably 5000 to 1,000,000, further preferably 10,000 to 500,000, particularly Preferably it is 50,000 to 500,000.

  The (meth) acrylic resin having a lactone ring structure has a Tg (glass transition temperature) of preferably 115 ° C. or higher, more preferably 125 ° C. or higher, further preferably 130 ° C. or higher, particularly preferably 135 ° C., most preferably Is 140 ° C. or higher. This is because it can have excellent durability. The upper limit of Tg of the (meth) acrylic resin having a lactone ring structure is not particularly limited, but is preferably 170 ° C. or lower from the viewpoint of moldability and the like.

  In this specification, “(meth) acrylic” refers to acrylic and / or methacrylic.

  The protective film 20 (first protective film 21) arranged on the side opposite to each retardation layer with respect to the polarizer may have a surface such as a hard coat treatment, an antireflection treatment, a sticking prevention treatment, an antiglare treatment, if necessary. It may be treated. The thickness of the protective film (first protective film) is typically 5 mm or less, preferably 1 mm or less, more preferably 1 μm to 500 μm, still more preferably 5 μm to 150 μm.

  The second protective film 22 arranged between the polarizer 10 and the first retardation layer 30 is preferably optically isotropic as described above. In the present specification, “optically isotropic” means that the in-plane retardation Re (550) is 0 nm to 10 nm, and the thickness direction retardation Rth (550) is -10 nm to +10 nm. Say. The above-mentioned optically anisotropic layer means, for example, a layer having an in-plane retardation Re (550) of more than 10 nm and / or a thickness direction retardation Rth (550) of less than -10 nm or more than 10 nm.

  The thickness of the second protective film is preferably 5 μm to 200 μm, more preferably 10 μm to 100 μm, still more preferably 15 μm to 95 μm.

A-6. Others Any appropriate pressure-sensitive adhesive layer or adhesive layer is used for laminating each layer constituting the polarizing plate of the present invention. The pressure-sensitive adhesive layer is typically formed of an acrylic pressure-sensitive adhesive. The adhesive layer is typically formed of a polyvinyl alcohol-based adhesive.

  Although not shown, a pressure-sensitive adhesive layer may be provided on the second retardation layer 40 side of the polarizing plates 100 and 100 ′. Since the pressure-sensitive adhesive layer is provided in advance, it can be easily attached to another optical member (for example, an organic EL panel). A release film is preferably attached to the surface of the pressure-sensitive adhesive layer until it is used.

B. Manufacturing Method Any appropriate method can be adopted as a manufacturing method of the polarizing plate. In one preferred embodiment, the elongated polarizer having an absorption axis in the longitudinal direction and the elongated first or second retardation layer are respectively conveyed in the longitudinal direction while the longitudinal direction of the polarizer is being conveyed. And a step of obtaining a laminated film by laminating so that the longitudinal direction of the retardation layer is aligned with each other, while conveying the laminated film and the elongated second or first retardation layer in the longitudinal direction, It is manufactured by a method including a step of laminating so that the longitudinal direction of the laminated film and the longitudinal direction of the retardation layer are aligned. In addition, the elongated first retardation layer and the elongated second retardation layer are laminated to produce a laminated retardation film, and the laminated retardation film and the elongated polarizer are combined. You may manufacture by laminating. Here, the angle θ formed by the absorption axis of the polarizer 10 and the slow axis of the first retardation layer 30 satisfies the relationship of 35 ° ≦ θ ≦ 55 °, and more preferably 38, as described above. ° ≦ θ ≦ 52 °, more preferably 39 ° ≦ θ ≦ 51 °.

  The elongated first retardation layer has a slow axis in the direction of an angle θ with respect to the longitudinal direction thereof. With such a configuration, as described above, roll-to-roll can be performed in the production of the polarizing plate, and the production process can be significantly shortened.

C. Organic EL Panel The organic EL panel of the present invention includes the above polarizing plate on the viewer side. The polarizing plate is laminated such that each retardation layer is on the organic EL panel side (the polarizer is on the viewing side).

  Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples. The measuring method of each characteristic is as follows.

(1) Thickness It was measured using a dial gauge (manufactured by PEACOCK, product name "DG-205", dial gauge stand (product name "pds-2")).
(2) Retardation A 50 mm × 50 mm sample was cut out from each retardation layer and measured using a measurement sample and Axoscan manufactured by Axometrics. The measurement wavelength was 450 nm and 550 nm, and the measurement temperature was 23 ° C.
Further, the average refractive index was measured using an Abbe refractometer manufactured by Atago Co., and the refractive indexes nx, ny and nz were calculated from the obtained phase difference values.
(3) Phase difference fluctuation due to environmental test A sample was cut out from the phase difference film into 50 mm x 50 mm, and the phase difference was measured by Axoscan. After that, the sample was allowed to stand in a thermo-hygrostat at 40 ° C. and 90% RH for 100 hours, then the phase difference was measured, and the difference between the phase differences before and after the environmental test was determined to evaluate.
(4) Water absorption rate The water absorption rate was measured according to "Testing method for water absorption rate and boiling water absorption rate of plastics" described in JIS K7209. The size of the test piece was a square of 50 mm side, and the test piece was immersed in water having a water temperature of 25 ° C. for 24 hours, and then the weight change before and after the immersion was measured to determine the size. The unit is%.
(5) Reflective Hue A black image was displayed on the obtained organic EL panel, and the reflective hue was measured using a viewing angle measuring and evaluating device Conoscope manufactured by Auronic-MERCHERS.

[Example 1]
(Production of polycarbonate resin film)
Isosorbide (ISB) 37.5 parts by mass, 9,9- [4- (2-hydroxyethoxy) phenyl] fluorene (BHEPF) 91.5 parts by mass, average molecular weight 400 polyethylene glycol (PEG) 8.4 parts by mass, First, 105.7 parts by mass of diphenyl carbonate (DPC) and 0.594 parts by mass of cesium carbonate (0.2% by mass aqueous solution) as a catalyst were put into a reaction vessel, respectively, and the first stage of the reaction was performed under a nitrogen atmosphere. In this step, the temperature of the heat medium in the reaction vessel was set to 150 ° C., and the raw materials were dissolved with stirring as necessary (about 15 minutes).

Then, the pressure inside the reaction vessel was changed from normal pressure to 13.3 kPa, and the generated phenol was extracted out of the reaction vessel while the temperature of the heat medium in the reaction vessel was raised to 190 ° C. in 1 hour.
After maintaining the temperature in the reaction vessel at 190 ° C for 15 minutes, the pressure in the reaction vessel was set to 6.67 kPa and the heat medium temperature in the reaction vessel was increased to 230 ° C in 15 minutes as the second step. The generated phenol was taken out of the reaction vessel. 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 reduced to 0.200 kPa or less in order to remove the generated phenol. After reaching a predetermined stirring torque, the reaction was terminated, the produced reaction product was extruded into water, and then pelletized, and BHEPF / ISB / PEG = 42.9 mol% / 52.8 mol% / 4.3. A polycarbonate resin A containing a structural unit derived from a dihydroxy compound in a proportion of mol% was obtained.
The obtained polycarbonate resin A had a glass transition temperature of 126 ° C. and a reduced viscosity of 0.372 dL / g.

After vacuum-drying the obtained polycarbonate resin A at 80 ° C. for 5 hours, a single-screw extruder (manufactured by Isuzu Chemical Co., Ltd., screw diameter 25 mm, cylinder setting temperature: 220 ° C.), T-die (width 300 mm, setting temperature: 220 ° C.), a chill roll (set temperature: 120 to 130 ° C.), and a film forming apparatus equipped with a winder were used to produce a polycarbonate resin film having a length of 3 m, a width of 300 mm, and a thickness of 120 μm.
The water absorption of the obtained polycarbonate resin film was 1.2%.

(Preparation of first retardation layer)
The obtained polycarbonate resin film was cut into a length of 300 mm and a width of 300 mm and longitudinally stretched at a temperature of 136 ° C. and a magnification of 2 using a Labo Stretcher KARO IV (manufactured by Bruckner) to obtain a retardation film. .
The Re (550) of the obtained retardation film was 141 nm and the Rth (550) was 141 nm (nx: 1.5969, ny: 1.5942, nz: 1.5942), and the refractive index of nx> ny = nz. Characterized. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
20 parts by weight of a side chain type liquid crystal polymer represented by the following chemical formula (I) (numerals 65 and 35 in the formula represent mol% of monomer units and are represented by a block polymer for convenience: weight average molecular weight 5000): 80 parts by weight of a polymerizable liquid crystal showing a nematic liquid crystal phase (manufactured by BASF: trade name Paliocolor LC242) and 5 parts by weight of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals: trade name Irgacure 907) were dissolved in 200 parts by weight of cyclopentanone. Then, a liquid crystal coating liquid was prepared. Then, the base film (norbornene-based resin film: manufactured by Nippon Zeon Co., Ltd., trade name “Zeonex”) is coated with the coating liquid by a bar coater, and then heated and dried at 80 ° C. for 4 minutes to form a liquid crystal. Oriented. By irradiating this liquid crystal layer with ultraviolet rays to cure the liquid crystal layer, a liquid crystal solidified layer (thickness: 0.58 μm) to be the second retardation layer was formed on the base material. Re (550) of this layer is 0 nm, Rth (550) is -71 nm (nx: 1.5326, ny: 1.5326, nz: 1.6550), and shows a refractive index characteristic of nz> nx = ny. It was

(Preparation of laminated body)
After the liquid crystal solidified layer (second retardation layer) is attached to the retardation film (first retardation layer) via an acrylic pressure-sensitive adhesive, the base film is removed to give a retardation. A laminate was obtained in which the liquid crystal solidified layer was transferred to the film.
The Re (550) of the obtained laminate was 141 nm and the Rth (550) was 70 nm.

(Production of polarizer)
The polyvinyl alcohol film was dyed in an aqueous solution containing iodine, and then uniaxially stretched 6 times between rolls having different speed ratios in an aqueous solution containing boric acid to obtain a polarizer.

(Production of polarizing plate)
A triacetyl cellulose film (thickness 40 μm, product name “KC4UYW” manufactured by Konica Minolta Co., Ltd.) was attached to one side of the above polarizer via a polyvinyl alcohol-based adhesive.
The retardation film was attached to the other side of the polarizer via a polyvinyl alcohol adhesive. Here, the retardation film was laminated so that the slow axis was 45 ° counterclockwise with respect to the absorption axis of the polarizer. Next, the liquid crystal solidified layer was attached to the retardation film side via an acrylic pressure-sensitive adhesive, and then the base film was removed to obtain a polarizing plate.

(Production of organic EL panel)
An adhesive layer was formed of an acrylic adhesive on the liquid crystal solidified layer (second retardation layer) side of the obtained polarizing plate and cut into a size of 50 mm × 50 mm.
Take out the organic EL panel from the organic EL display (product name "15EL9500" manufactured by LG), peel off the polarizing film attached to this organic EL panel, and instead attach the cut out polarizing plate to the organic EL display. Got the panel.
Table 1 shows the measurement results of the reflection hue of this organic EL panel. In Table 1, the "viewing angle characteristic" is defined as the reflection hue in the front direction and the reflection hue in the oblique direction (maximum value or minimum value at a polar angle of 45 °) on the xy chromaticity diagram of the CIE color system. The distance between two points Δxy is shown. Further, “change in frontal hue Δxy” and “change in oblique hue Δxy” indicate changes in reflected hue before and after the environmental test is applied.

[Example 2]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 1.85 times.
The Re (550) of the obtained retardation film was 120 nm and the Rth (550) was 120 nm (nx: 1.5967, ny: 1.5944, nz: 1.5944), and the refractive index of nx> ny = nz. Characterized. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.66 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -80 nm, respectively (nx: 1.5339, ny: 1.5339, nz: 1.6551), and refraction of nz> nx = ny. The rate characteristics are shown.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 3]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.1 times.
The Re (550) of the obtained retardation film was 160 nm and the Rth (550) was 160 nm (nx: 1.5971, ny: 1.5940, nz: 1.5940), and the refractive index of nx> ny = nz. Characterized. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.49 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -60 nm, respectively (nx: 1.5325, ny: 1.5325, nz: 1.6549), and refraction of nz> nx = ny. The rate characteristics are shown.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 100 nm.

[Example 4]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) was used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(First retardation layer)
A commercially available retardation film (manufactured by Teijin Ltd., trade name “Pure Ace WR (EWF)”) was used as it was. This film had Re (550) of 147 nm and Rth (550) of 147 nm (nx: 1.5970, ny: 1.5942, nz: 1.5942), and exhibited a refractive index characteristic of nx> ny = nz. . The Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the water absorption was 0.5%, and the phase difference variation due to the environmental test was 5 nm.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film was used.
The Re (550) of the obtained laminate was 147 nm and the Rth (550) was 76 nm.

[Example 5]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) was used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(First retardation layer)
By the procedure according to Example 1, a polycarbonate resin B containing structural units derived from a dihydroxy compound was obtained at a ratio of BHEPF / ISB / PEG (average molecular weight 1000) = 45 mol% / 51 mol% / 4 mol%. The glass transition temperature of the obtained polycarbonate resin B was 134.1 ° C. A polycarbonate resin film was produced in the same manner as in Example 1 except that this polycarbonate resin B was used. The water absorption of the obtained polycarbonate resin film was 2.1%.
A retardation film (first retardation layer) was obtained in the same manner as in Example 1 except that this polycarbonate resin film was used and that longitudinal stretching was performed at a stretching ratio of 1.5 times. The Re (550) and Rth (550) of the obtained retardation film were 141 nm and 141 nm, respectively, and exhibited refractive index characteristics of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.98. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film was used.
The Re (550) of the obtained laminate was 141 nm and the Rth (550) was 70 nm.

[Comparative Example 1]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal cured layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(First retardation layer)
The cellulose ester film of Example 1 of JP-A-2005-42039 (water absorption rate: 3.2%) was used at a temperature of 100 ° C and a magnification of 1.3 times using a lab stretcher KARO IV (manufactured by Bruckner). Simultaneously biaxially stretched, a retardation film was obtained.
Re (550) of the obtained retardation film was 0 nm, Rth (550) was 141 nm (nx: 1.4912, ny: 1.4912, nz: 1.4877), and a refractive index of nx = ny> nz. Characterized. The water absorption was 3.2%, and the phase difference variation due to the environmental test was 15 nm.

(Preparation of second retardation layer)
Liquid crystal compound [Dainippon Ink and Chemicals, Inc., trade name "UCL-001"] 100 parts by weight, photopolymerization initiator [Ciba Specialty Chemicals Co., Ltd., trade name "Irgacure 907"] 3 parts by weight And a leveling agent [manufactured by BYK Chemie, trade name "BYK361"] in an amount of 0.05 part by weight were dissolved in 200 parts by weight of cyclopentanone (boiling point 131 ° C) to prepare a solution. Then, on the surface of a commercially available polyethylene terephthalate film [manufactured by Toray Industries, Inc., trade name “S-27E” (thickness: 75 μm)], commercially available polyvinyl alcohol [manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “NH-18 ]] Is uniformly applied in one direction using a rod coater and dried in an air circulation type constant temperature oven at 80 ° C. 70 ° C. ± 1 ° C. for 5 minutes, and then a rubbing cloth having nylon pile yarn is applied. Rabink treatment (rotation number: 1000 rpm, indentation amount: 0.30 mm, moving speed: 60 mm / sec) was performed using the attached cylindrical roller to obtain an alignment substrate. After coating the prepared liquid crystal solution on the surface of the obtained alignment base material using a rod coater, and drying for 3 minutes in an air circulation type constant temperature oven at 90 ° C. ± 1 ° C., and after coating and drying , And then cured by UV irradiation to form a cured layer of the liquid crystalline composition aligned in a homogeneous array.
Re (550) and Rth (550) of the obtained cured layer were 141 nm and 141 nm, respectively (nx: 1.4916, ny: 1.4893, nz: 1.4893), and refractive index characteristics of nx> ny = nz. showed that.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal cured layer were used.
Re (550) of the obtained laminated body was 141 nm, and Rth (550) was 282 nm.

[Comparative Example 2]
An organic EL panel was produced in the same manner as in Example 1 except that the second retardation layer was not used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

[Comparative Example 3]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) was used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
5.0 g of PVA (NH-18, Japan Synthetic Chemical Industry) having a degree of polymerization of 1800 dried at 105 ° C. for 2 hours was dissolved in 95 ml of DMSO. Mesitaldehyde (3.78 g), propionaldehyde (1.81 g) and p-toluenesulfonic acid monohydrate (1.77 g) were added thereto, and the mixture was stirred at 40 ° C. for 4 hours. Reprecipitation was carried out in a water / methanol = 2/1 solution in which 2.35 g of sodium hydrogen carbonate was dissolved. The polymer obtained by filtration was dissolved in THF and reprecipitated in diethyl ether. After filtering and drying, 7.89 g of a white polymer was obtained. When the obtained polymer was measured under the above-mentioned measurement conditions, the molar ratio of each site of vinyl mesital, vinyl propional and vinyl alcohol was 22:46:32, and the polymer having the structure represented by the following chemical formula (II) was obtained. Was obtained. The glass transition temperature of this polymer was 102 ° C. The obtained polymer was dissolved in DMF and a film was formed using an applicator. The film obtained by drying was stretched 1.8 times at 110 ° C. using a stretching machine to obtain a uniaxially stretched film having a thickness of 85 μm.
The obtained film had Re (550) of 141 nm and Rth (550) of 141 nm (nx: 1.5969, ny: 1.5942, nz: 1.5942), and had a refractive index characteristic of nx> ny = nz. Indicated. The Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the water absorption rate was 4.9%, and the phase difference variation due to the environmental test was 20 nm.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film was used.
The Re (550) of the obtained laminate was 141 nm and the Rth (550) was 70 nm.

[Comparative Example 4]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 1.82 times.
The Re (550) and Rth (550) of the obtained retardation film were 115 nm and 115 nm (nx: 1.5966, ny: 1.5944, nz: 1.5944), and the refractive index of nx> ny = nz. Characterized. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
Thickness: A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.7 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -85 nm, respectively (nx: 1.5338, ny: 1.5338, nz: 1.6552), and refraction of nz> nx = ny. The rate characteristics are shown.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 115 nm and the Rth (550) was 30 nm.

[Comparative Example 5]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.13 times.
The retardation film thus obtained had an Re (550) of 170 nm and an Rth (550) of 170 nm (nx: 1.5972, ny: 1.5939, nz: 1.5939) and a refractive index of nx> ny = nz. Characterized. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.49 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -60 nm, respectively (nx: 1.5325, ny: 1.5325, nz: 1.6549), and refraction of nz> nx = ny. The rate characteristics are shown.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 170 nm and the Rth (550) was 110 nm.

[Example 6]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 1.7 times.
The retardation film thus obtained had an Re (550) of 100 nm and an Rth (550) of 100 nm and exhibited a refractive index characteristic of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A 30 liter autoclave was charged with 18 kg of distilled water containing 0.2% by weight of partially saponified polyvinyl alcohol, 3 kg of diisopropyl fumarate, and 7 g of dimethyl-2,2'-azobisisobutyrate as a polymerization initiator. The suspension radical polymerization reaction was carried out under the conditions of 50 ° C. and a polymerization time of 24 hours. The obtained particles were filtered, thoroughly washed with methanol, and then dried at 80 ° C. to obtain a diisopropyl fumarate homopolymer. The obtained diisopropyl fumarate homopolymer was dissolved in a THF solution to obtain a 22% solution, and 100 parts by weight of the diisopropyl fumarate homopolymer was further treated with tris (2,4-di-) as a hindered phenol antioxidant. 0.35 parts by weight of t-butylphenyl) phosphite and 0.15 parts by weight of pentaerythritol-tetrakis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) as a phosphorus-based antioxidant, After adding 1 part by weight of 2- (2H-benzotriazol-2-yl) -p-cresol as an ultraviolet absorber, the solution was cast on a supporting substrate of a solution casting apparatus by a T-die method, and 40 ° C, 80 ° C and A film having a thickness of 20.7 μm was obtained, which was dried at 120 ° C. for 15 minutes each.
The obtained film was cut into a length of 300 mm and a width of 300 mm, and free-end longitudinal stretching was performed at a temperature of 150 ° C. and a magnification of 1.05 using a Labo Stretcher KARO IV (manufactured by Bruckner) to obtain a retardation film. Obtained.
The Re (550) and Rth (550) of the obtained retardation film were 20 nm and -60 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 7]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(First retardation layer)
The retardation film produced in Example 1 was used.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the thickness was 14.8 μm. The Re (550) and Rth (550) of the obtained retardation film were 20 nm and -40 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminated body was obtained in the same manner.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 100 nm.

[Example 8]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(First retardation layer)
The retardation film produced in Example 1 was used.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the thickness was 14.8 μm. The Re (550) and Rth (550) of the obtained retardation film were 20 nm and -40 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 100 nm.

[Example 9]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.2 times.
The Re (550) and Rth (550) of the obtained retardation film were 170 nm and 170 nm, respectively, and exhibited refractive index characteristics of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.025 and the thickness was 40 μm. The Re (550) and Rth (550) of the obtained retardation film were 10 nm and -130 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminated body was obtained in the same manner.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 40 nm.

[Example 10]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
The commercially available retardation film used in Example 4 was fixed-end stretched at a stretching temperature of 190 ° C. (MD stretching ratio 0.85 times, TD stretching ratio 1.1 times) to obtain a first retardation layer retardation film. I got a film.
The retardation film thus obtained had an Re (550) of 100 nm and an Rth (550) of 100 nm and exhibited a refractive index characteristic of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Second retardation layer)
The retardation film produced in Example 6 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 11]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
The commercially available retardation film used in Example 4 was stretched at a stretching temperature of 190 ° C. and a stretching ratio of 1.2 times to obtain a first retardation film for a retardation layer.
The Re (550) and Rth (550) of the obtained retardation film were 170 nm and 170 nm, respectively, and exhibited refractive index characteristics of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.025 and the thickness was 40 μm. The Re (550) and Rth (550) of the obtained retardation film were 10 nm and -130 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminated body was obtained in the same manner.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 40 nm.

[Comparative Example 6]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 1.6 times.
The Re (550) and Rth (550) of the obtained retardation film were 90 nm and 90 nm, respectively, and exhibited refractive index characteristics of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Second retardation layer)
The retardation film produced in Example 6 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 110 nm and the Rth (550) was 30 nm.

[Comparative Example 7]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.3 times.
The retardation film thus obtained had an Re (550) of 180 nm and an Rth (550) of 180 nm and exhibited a refractive index characteristic of nx> ny = nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.025 and the thickness was 40 μm. The Re (550) and Rth (550) of the obtained retardation film were 10 nm and -130 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminated body was obtained in the same manner.
The Re (550) of the obtained laminate was 170 nm and the Rth (550) was 50 nm.

[Comparative Example 8]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Comparative Example 1 except that the free end drawing was performed at a draw ratio of 1.2 times.
The retardation film thus obtained had an Re (550) of 100 nm and an Rth (550) of 100 nm and exhibited a refractive index characteristic of nx> ny = nz. Further, the water absorption of the obtained retardation film was 3.2%, and the retardation variation due to the environmental test was 15 nm.

(Second retardation layer)
The retardation film produced in Example 6 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Comparative Example 9]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as Comparative Example 3 except that the stretching ratio was 1.28 times.
The retardation film thus obtained had an Re (550) of 100 nm and an Rth (550) of 100 nm and exhibited a refractive index characteristic of nx> ny = nz. The water absorption of the obtained retardation film was 4.9%, and the variation of the retardation by the environmental test was 20 nm.

(Second retardation layer)
The retardation film produced in Example 6 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 12]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.2 times.
The Re (550) and Rth (550) of the obtained retardation film were 120 nm and 130 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.75 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -90 nm, respectively, and exhibited refractive index characteristics of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 13]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(First retardation layer)
The retardation film produced in Example 12 was used.

(Preparation of second retardation layer)
Thickness: A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.25 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -30 nm, respectively, and exhibited a refractive index characteristic of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 100 nm.

[Example 14]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that free end stretching was performed at an MD stretching ratio of 3.2 times, and then fixed end stretching was performed at a TD stretching ratio of 1.5 times.
The retardation film thus obtained had an Re (550) of 160 nm and an Rth (550) of 380 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
Thickness: A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 2.31 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -280 nm, respectively, and exhibited a refractive index characteristic of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 100 nm.

[Example 15]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.6 times.
The retardation film thus obtained had an Re (550) of 160 nm and an Rth (550) of 170 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 1.07 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -130 nm, respectively, and exhibited a refractive index characteristic of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 40 nm.

[Example 16]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
The commercially available retardation film used in Example 4 was simultaneously biaxially stretched at a stretching temperature of 190 ° C. (MD stretching ratio 0.85 times, TD stretching ratio 1.1 times), and then fixed-end stretching (MD stretching ratio 1 . 1) to obtain a first retardation film for retardation layer.
The Re (550) and Rth (550) of the obtained retardation film were 120 nm and 130 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
Thickness: A liquid crystal solidified layer was obtained in the same manner as in Example 4, except that the thickness was adjusted to 0.75 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -90 nm, respectively, and exhibited refractive index characteristics of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 17]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
The commercially available retardation film used in Example 4 was fixed-end stretched at a stretching temperature of 190 ° C. (stretching ratio 1.2 times) to obtain a first retardation film for retardation layer.
The retardation film thus obtained had an Re (550) of 160 nm and an Rth (550) of 170 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 4 except that the thickness was adjusted to 1.07 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -130 nm, respectively, and exhibited a refractive index characteristic of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 40 nm.

[Comparative Example 10]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.25 times.
The retardation film thus obtained had an Re (550) of 130 nm and an Rth (550) of 141 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
Thickness: A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 0.25 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -30 nm, respectively, and exhibited a refractive index characteristic of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 130 nm and the Rth (550) was 111 nm.

[Comparative Example 11]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the stretching ratio was 2.5 times.
The Re (550) and Rth (550) of the obtained retardation film were 150 nm and 181 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Example 1 except that the thickness was adjusted to 1.33 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -160 nm, respectively, and exhibited a refractive index characteristic of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 150 nm and the Rth (550) was 21 nm.

[Comparative Example 12]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Comparative Example 1 except that fixed end stretching with an MD stretching ratio of 1.3 times was performed.
The Re (550) and Rth (550) of the obtained retardation film were 120 nm and 130 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. Further, the water absorption of the obtained retardation film was 3.2%, and the retardation variation due to the environmental test was 15 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Comparative Example 1 except that the thickness was adjusted to 0.75 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -90 nm, respectively, and exhibited refractive index characteristics of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Comparative Example 13]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation film (first retardation layer) and liquid crystal solidified layer (second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Comparative Example 3 except that fixed-end stretching with an MD stretching ratio of 2.3 was performed.
The Re (550) and Rth (550) of the obtained retardation film were 120 nm and 130 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The water absorption of the obtained retardation film was 4.9%, and the variation of the retardation by the environmental test was 20 nm.

(Preparation of second retardation layer)
A liquid crystal solidified layer was obtained in the same manner as in Comparative Example 3 except that the thickness was adjusted to 0.75 μm.
The Re (550) and Rth (550) of the obtained liquid crystal solidified layer were 0 nm and -90 nm, respectively, and exhibited refractive index characteristics of nz> nx = ny.

(Preparation of laminated body)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and the liquid crystal solidified layer were used.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 18]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the film was sequentially biaxially stretched (fixed end stretching at MD stretching ratio of 1.6 times and then transverse stretching at TD stretching ratio of 1.26 times).
The Re (550) and Rth (550) of the obtained retardation film were 40 nm and 100 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.2 times and the thickness was 41 μm. The Re (550) and Rth (550) of the obtained retardation film were 80 nm and -60 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Examples except that each of the above retardation films was used and that the retardation axes of the first retardation layer and the second retardation layer were arranged to be substantially parallel to each other. A laminated body was obtained in the same manner as in 1.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 19]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the film was sequentially biaxially stretched (fixed-end stretching at an MD stretching ratio of 2.7 times and then transversely stretched at a TD stretching ratio of 1.1 times).
The retardation film thus obtained had an Re (550) of 160 nm and an Rth (550) of 180 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.1 times and the thickness was 35 μm. The Re (550) and Rth (550) of the obtained retardation film were 40 nm and -80 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 100 nm.

[Example 20]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the film was sequentially biaxially stretched (fixed-end stretching at an MD stretching ratio of 1.65 times and then transversely stretched at a TD stretching ratio of 1.31 times).
The Re (550) and Rth (550) of the obtained retardation film were 40 nm and 120 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.3 times and the thickness was 41 μm. The Re (550) and Rth (550) of the obtained retardation film were 120 nm and -20 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Examples except that each of the above retardation films was used and that the retardation axes of the first retardation layer and the second retardation layer were arranged to be substantially parallel to each other. A laminated body was obtained in the same manner as in 1.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 100 nm.

[Example 21]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the fixed-end stretching was performed at an MD stretching ratio of 2.75 times.
The retardation film thus obtained had an Re (550) of 170 nm and an Rth (550) of 180 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.025 and the thickness was 45.5 μm. The Re (550) of the obtained retardation film was 10 nm, the Rth (550) was -140 nm, and the refractive index characteristics of nz>nx> ny were exhibited.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 40 nm.

[Example 22]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
The commercially available retardation film used in Example 4 was simultaneously biaxially stretched at a stretching temperature of 190 ° C. (MD stretching ratio 0.85 times, TD stretching ratio 1.2 times), and the first retardation layer retardation I got a film.
The Re (550) and Rth (550) of the obtained retardation film were 40 nm and 100 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Second retardation layer)
The retardation film produced in Example 18 was used.

(Preparation of laminated body)
Examples except that each of the above retardation films was used and that the retardation axes of the first retardation layer and the second retardation layer were arranged to be substantially parallel to each other. A laminated body was obtained in the same manner as in 1.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Example 23]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
The commercially available retardation film used in Example 4 was fixed-end stretched at a stretching ratio of 1.25 to obtain a first retardation film for retardation layer.
The retardation film thus obtained had an Re (550) of 170 nm and an Rth (550) of 180 nm and exhibited a refractive index characteristic of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Second retardation layer)
The retardation film produced in Example 21 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 160 nm and the Rth (550) was 40 nm.

[Comparative Example 14]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the film was sequentially biaxially stretched (fixed end stretching at an MD stretching ratio of 1.65 times and then transversely stretching at a TD stretching ratio of 1.3 times).
The Re (550) and Rth (550) of the obtained retardation film were 50 nm and 125 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.2 times and the thickness was 50 μm. The Re (550) and Rth (550) of the obtained retardation film were 80 nm and -90 nm, respectively, and exhibited refractive index characteristics of nz>nx> ny.

(Preparation of laminated body)
Examples except that each of the above retardation films was used and that the retardation axes of the first retardation layer and the second retardation layer were arranged to be substantially parallel to each other. A laminated body was obtained in the same manner as in 1.
The Re (550) of the obtained laminate was 130 nm and the Rth (550) was 35 nm.

[Comparative Example 15]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Example 1 except that the fixed end stretching was performed at the MD stretching ratio of 2.8 times.
The Re (550) and Rth (550) of the obtained retardation film were 180 nm and 190 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The Re (450) / Re (550) of the obtained retardation film was 0.89. Further, the phase difference variation due to the environmental test was 5 nm.

(Preparation of second retardation layer)
A retardation film was obtained in the same manner as in Example 6 except that the stretching ratio was 1.025 and the thickness was 26.6 μm. The Re (550) of the obtained retardation film was 10 nm, the Rth (550) was -80 nm, and the refractive index characteristics of nz>nx> ny were shown.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 170 nm and the Rth (550) was 110 nm.

[Comparative Example 16]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Comparative Example 1 except that it was sequentially biaxially stretched (free-end stretched at MD stretch ratio of 1.18 and then transversely stretched at TD stretch ratio of 1.08).
The Re (550) and Rth (550) of the obtained retardation film were 40 nm and 100 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. Further, the water absorption of the obtained retardation film was 3.2%, and the retardation variation due to the environmental test was 15 nm.

(Second retardation layer)
The retardation film produced in Example 18 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

[Comparative Example 17]
An organic EL panel was produced in the same manner as in Example 1 except that the following retardation films (first retardation layer and second retardation layer) were used.
Table 1 shows the measurement results of the reflection hue of this organic EL panel.

(Preparation of first retardation layer)
A retardation film was obtained in the same manner as in Comparative Example 3 except that it was sequentially biaxially stretched (fixed-end stretching at an MD stretching ratio of 1.96 times and then transversely stretched at a TD stretching ratio of 1.37 times).
The Re (550) and Rth (550) of the obtained retardation film were 40 nm and 100 nm, respectively, and exhibited refractive index characteristics of nx>ny> nz. The water absorption of the obtained retardation film was 4.9%, and the variation of the retardation by the environmental test was 20 nm.

(Second retardation layer)
The retardation film produced in Example 18 was used.

(Preparation of laminated body)
Example 1 except that each of the above retardation films was used and the retardation axis of the first retardation layer and the retardation axis of the second retardation layer were arranged to be substantially parallel to each other. A laminate was obtained in the same manner as.
The Re (550) of the obtained laminate was 120 nm and the Rth (550) was 40 nm.

  In each of the examples, the viewing angle characteristics were less than 0.07 and good, and the hue changes Δxy in both the front and diagonal directions were less than 0.07 and good. In the comparative example in which the water absorption of the first retardation layer or the Re (550) or Rth (550) of the laminate of the first retardation layer and the second retardation layer is out of the range of the present invention, Was insufficient in at least one of the viewing angle characteristic, the change Δxy in the front hue and the change Δxy in the oblique hue.

  The polarizing plate of the present invention is suitably used for an organic EL device.

10 Polarizer 20 Protective film 21 1st protective film 22 2nd protective film 30 1st retardation layer 40 2nd retardation layer 100 Polarizing plate 100 'Polarizing plate

Claims (7)

A polarizer, a first retardation layer, and a second retardation layer are provided in this order ,
The first retardation layer exhibits a refractive index characteristic of nx> ny ≧ nz and satisfies the relationship of Re (450) <Re (550),
The second retardation layer exhibits a refractive index characteristic of nz>nx> ny , and its Re (550) is more than 10 nm and 150 nm or less,
The angle θ formed by the absorption axis of the polarizer and the slow axis of the first retardation layer satisfies the relationship of 35 ° ≦ θ ≦ 55 °,
Re (550) of the laminate of the first retardation layer and the second retardation layer is 120 nm to 160 nm,
Rth (550) of the second retardation layer is −260 nm to −10 nm,
The water absorption of the first retardation layer is 3% or less,
Used in organic EL panels,
Polarizer:
Here, Re (450) and Re (550) represent in-plane retardation measured with light having a wavelength of 450 nm and 550 nm at 23 ° C., respectively, and Rth (550) is measured with light having a wavelength of 550 nm at 23 ° C. The phase difference in the thickness direction is shown.   The polarizing plate according to claim 1, wherein an optical anisotropic layer is not included between the polarizer and the first retardation layer or the second retardation layer. The polarizing plate according to claim 1 or 2, wherein the first retardation layer is formed of a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following general formula (1).

(In the general formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted 6 to 20 carbon atoms. Or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, X is a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, a substituted or unsubstituted carbon number A cycloalkylene group having 6 to 20 carbon atoms or a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, m and n are each independently an integer of 0 to 5.) The polarizing plate according to any one of claims 1 to 3, wherein the first retardation layer is formed of a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following general formula (2). .

The polarizing plate according to any one of claims 1 to 4, wherein the first retardation layer is formed of a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following general formula (5). .

(In the general formula (5), R ₇ represents a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, and p is an integer of 2 to 100.)   The polarizing plate according to any one of claims 1 to 5, wherein the first retardation layer is a retardation film obtained by oblique stretching. An organic EL panel comprising the polarizing plate according to claim 1.

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