JP2014167922A - Polarizing plate and organic el panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polarizing plate suppressing variations in excellent viewing angle characteristics and display characteristics.SOLUTION: A polarizing plate of the present invention is used in an organic EL panel, and includes a polarizer 10, a first phase difference layer 30, and a second phase difference layer 40. The first phase difference layer 30 exhibits refractive index characteristics of nx>ny=nz, satisfies the relationship: Re (450)<Re (550), and has a water absorption of 3% or less. The second phase difference layer 40 exhibits refractive index characteristics of nz>nx≥ny. The angle θ formed between an absorption axis of the polarizer 10 and a lagging axis of the first phase difference layer 30 satisfies the relationship: 35°≤θ≤55°. The Re (550) of a laminate of the first phase difference layer 30 and the second phase difference layer 40 is 120-160 nm, and the Rth (550) is 40-100 nm.

Description

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

  In recent years, with the spread 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 tend to occur. Thus, it is known to prevent these problems by providing a circularly polarizing plate on the viewing side. 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. A laminate of 45 ° is known. It is known that a retardation film of a COP resin has a so-called flat wavelength dispersion characteristic in which a retardation value is substantially constant without depending on the wavelength of measurement light. When a circularly polarizing plate including a retardation film having such flat wavelength dispersion characteristics is used in an organic EL panel, there is a problem that an excellent reflection hue cannot be obtained.

  In order to solve the above problems, a circularly polarizing plate including a retardation film having a so-called reverse dispersion wavelength dependency (reverse dispersion wavelength characteristic) in which a retardation value increases according to the wavelength of measurement light has been proposed. (For example, Patent Document 1). When such a circularly polarizing plate is used for an organic EL panel, external light reflection and 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 is a serious problem. There has also been a problem that the display characteristics of the panel change with time.

Japanese Patent No. 3325560

  The present invention has been made in order to solve the above-described 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 in an organic EL panel, and includes a polarizer, a first retardation layer, and a second retardation layer, and the first retardation layer has a refractive index of nx> ny = nz. The second retardation layer exhibits a refractive index characteristic of nz> nx ≧ ny, and satisfies the relationship of Re (450) <Re (550) . The angle θ formed with the slow axis of the retardation layer satisfies the relationship of 35 ° ≦ θ ≦ 55 °, and Re (550) of the stacked body of the first retardation layer and the second retardation layer. ) 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, a substituted or unsubstituted carbon atom having 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, 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 retardation film is obtained by obliquely stretching the first retardation layer.
According to another aspect of the present invention, an organic EL panel is provided. This organic EL panel includes the polarizing plate.

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

(A) is a schematic sectional drawing of the polarizing plate by preferable embodiment of this invention, (b) is a schematic sectional drawing of the polarizing plate by another preferable embodiment of this invention.

  Hereinafter, although preferable embodiment of this invention is described, this invention is not limited to these embodiment.

(Definition of terms and symbols)
The definitions of terms and symbols in this specification are as follows.
(1) Refractive index (nx, ny, nz)
“Nx” is the refractive index in the direction in which the in-plane refractive index is maximum (ie, the slow axis direction), and “ny” is the direction orthogonal to the slow axis in the plane (ie, the fast axis direction). “Nz” is the refractive index in the thickness direction.
(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 obtained by the formula: Re = (nx−ny) × d, where d (nm) is the thickness of the layer (film). “Re (450)” is an in-plane retardation measured with light having a wavelength of 450 nm at 23 ° C.
(3) Thickness direction retardation (Rth)
“Rth (550)” is a retardation in the thickness direction measured with light having a wavelength of 550 nm at 23 ° C. Rth (550) is determined by the formula: Rth = (nx−nz) × d, where d (nm) is the thickness of the layer (film). “Rth (450)” is a retardation in the thickness direction measured with light having a wavelength of 450 nm at 23 ° C.
(4) Nz coefficient The Nz coefficient is obtained by Nz = Rth / Re.

A. Polarizing plate The polarizing plate of the present invention comprises 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, specific examples will be described.

  FIG. 1A is a schematic cross-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 layer 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 disposed so as to be closer to the polarizer 10 than the second retardation layer 40. However, the second retardation layer 40 is disposed on the polarizer 10 side. It may be. In the present embodiment, the first retardation layer 30 (second retardation layer 40) can also function as a protective layer of the polarizer 10. Further, since the polarizer and the first retardation layer (second retardation layer) are directly bonded in this way, a more excellent reflection hue (particularly viewing angle characteristics) is achieved, and display characteristics are achieved. Can be suppressed.

  FIG.1 (b) is a schematic sectional drawing of the polarizing plate by another preferable embodiment of this invention. The polarizing plate 100 ′ includes a polarizer 10, a first protective film 21 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. A retardation layer 40 and a second protective film 22 disposed between the polarizer 10 and the first retardation layer 30 are provided. Preferably, the second protective film 22 is optically isotropic. When the second protective film is optically isotropic, a more excellent reflection hue (particularly, viewing angle characteristics) can be achieved. In the illustrated example, the first retardation layer 30 is disposed on the polarizer 10 side relative to the second retardation layer 40, but the second retardation layer 40 is disposed on 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 so 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 between 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 it 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 may be adopted as the 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 thereof include polyene-based oriented films such as those subjected to the dyeing treatment and stretching treatment according to the above, polyvinyl alcohol dehydrated products and polyvinyl chloride dehydrochlorinated products. Preferably, a polarizer obtained by dyeing a polyvinyl alcohol film with iodine and uniaxially stretching is used because of 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. The stretching may be performed after the dyeing treatment or may be performed while dyeing. Moreover, you may dye | stain after extending | stretching. If necessary, the polyvinyl alcohol film is subjected to swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like. For example, by immersing a polyvinyl alcohol film in water and washing it before dyeing, not only can the surface of the polyvinyl alcohol film be cleaned and anti-blocking agents can be washed, but the polyvinyl alcohol film can be swollen and dyed. Unevenness can be prevented.

  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 exhibits a relationship of refractive index characteristics 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, and still more preferably 110 nm to 170 nm.

  The first retardation layer exhibits so-called reverse dispersion wavelength dependency. Specifically, the in-plane retardation satisfies the relationship Re (450) <Re (550). By satisfying such a relationship, an excellent reflection 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, still more preferably 1 to 1.5, and particularly preferably 1 to 1.3. By satisfying such a relationship, a more excellent reflection hue can be achieved.

  The first retardation 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 changes in display characteristics over time. In addition, a water absorption rate can be calculated | required based on JISK7209.

  The first retardation layer is typically a retardation film formed of any appropriate resin. As the resin for forming the retardation film, a polycarbonate resin is preferably used.

  In a preferred embodiment, the polycarbonate resin includes 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 the following: The dihydroxy compound represented by the general formula (3), the dihydroxy compound represented by the following general formula (4), the dihydroxy compound represented by the following general formula (5), and the dihydroxy compound represented by the following general formula (6) 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, a substituted or unsubstituted carbon atom having 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, 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 substituted or unsubstituted monocyclic cycloalkylene group 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 substituted or unsubstituted monocyclic cycloalkylene group 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, 2-dimethylpropoxy) phenyl) fluorene and the like are exemplified, and preferably 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene 9,9-bis (4- (2-hydroxyethoxy) -3-methylphenyl) fluorene, 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 isoide which have a stereoisomeric relationship. These may be used alone or in combination of two or more. Among these dihydroxy compounds, isosorbide obtained by dehydrating condensation of sorbitol produced from various starches that are abundant as resources and are readily available is easy to obtain and manufacture, optical properties, moldability From the viewpoint of the above, it is most preferable.

<Dihydroxy compound represented by the general formula (3)>
Examples of the dihydroxy compound represented by the general formula (3) include a compound containing a monocyclic cycloalkylene group (an alicyclic dihydroxy compound). By setting it as a monocyclic structure, the toughness when the polycarbonate resin obtained is used as a film can be improved. Representative examples of the alicyclic dihydroxy compound include compounds having a 5-membered ring structure or a 6-membered ring structure. By being a 5-membered ring structure or a 6-membered ring structure, the heat resistance of the obtained polycarbonate resin can be increased. The six-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- And cyclohexanediol. The dihydroxy compound represented by the general formula (3) may be used alone or in combination of two or more.

<Dihydroxy compound represented by the general formula (4)>
Examples of the dihydroxy compound represented by the general formula (4) include a compound containing a monocyclic cycloalkylene group (an alicyclic dihydroxy compound). By setting it as a monocyclic structure, the toughness when the polycarbonate resin obtained is used as a film can be improved. As a typical example of the alicyclic dihydroxy compound, R ₆ in the general formula (4) is the following general formula (Ia) (wherein R ³ is a hydrogen atom, or substituted or unsubstituted carbon number 1 to carbon number). Represents an alkyl group of 12)). Preferable specific examples of such isomers include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol and the like. These are easily available and excellent in handleability. The dihydroxy compound represented by the general formula (4) may be used alone or in combination of two or more.

  In addition, the compound illustrated above regarding the dihydroxy compound represented with General formula (3) and (4) is an example of the alicyclic dihydroxy compound which can be used, Comprising: It is not limited to these at all.

<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, and 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 them, propylene glycol, 1,4-butanediol, and spiroglycol are preferable.

  Structural unit derived from dihydroxy compound represented by general formula (3), structural unit derived from dihydroxy compound represented by general formula (4), derived from dihydroxy compound represented by general formula (5) Among the structural units derived from the dihydroxy compound represented by the general formula (4) and / or the structural unit derived from the dihydroxy compound represented by the general formula (6) and / or the general formula (5) It is preferable that the structural unit derived from the dihydroxy compound represented by this is included, and it is more preferable that the structural unit derived from the dihydroxy compound represented by the said General formula (5) is included. By including 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 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-hydride) 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 and 4,4'-dihydroxy-2,5-diethoxydiphenyl ether.

  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, and more preferably 25 mol% or more. If the structural unit is too small, the wavelength dependence of reverse 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 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, and still more preferably 35 mol% or more in the polycarbonate resin. It is. If the number of structural units is too 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, more preferably 120 ° C. or higher and 140 ° C. or lower. If the glass transition temperature is excessively low, the heat resistance tends to deteriorate, there is a possibility of causing a dimensional change after film formation, and the image quality of the resulting organic EL panel may be lowered. If the glass transition temperature is excessively high, the molding stability at the time of film molding may deteriorate, 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 a reduced viscosity. The reduced viscosity is measured using a Ubbelohde viscometer at a temperature of 20.0 ° C. ± 0.1 ° C., using methylene chloride as a solvent, precisely adjusting the polycarbonate concentration to 0.6 g / dL. 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, still more preferably 0.80 dL / g. If the reduced viscosity is less than the lower limit, there may be a problem that the mechanical strength of the molded product is reduced. On the other hand, if the reduced viscosity is larger than the upper limit, the fluidity at the time of molding is lowered, and there may be a problem that productivity and moldability are lowered.

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

  Any appropriate method can be adopted as a method of forming the resin film. For example, a melt extrusion method (for example, a T-die molding method), a cast coating method (for example, a casting method), a calendar molding method, a hot press method, a co-extrusion method, a co-melting method, a multilayer extrusion method, an inflation molding method, etc. It is done. 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 later, and the like. Preferably it is 50 micrometers-300 micrometers.

  Any appropriate stretching method and stretching conditions (for example, stretching temperature, stretching ratio, stretching direction) can be adopted for the stretching. Specifically, various stretching methods such as free end stretching, fixed end stretching, free end contraction, and fixed end contraction can be used singly 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, and 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 a resin film or uniaxially stretching a fixed end. As a specific example of the fixed end uniaxial stretching, there is a method of stretching in the width direction (lateral 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 obliquely 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. For example, when laminating with a polarizer Roll-to-roll is possible, and the manufacturing process can be simplified.

  Examples of the stretching machine used for the oblique stretching include a tenter-type stretching machine that can apply a feeding force, a pulling force, or a pulling force at different speeds in the lateral and / or longitudinal direction. The tenter type stretching machine includes a horizontal uniaxial stretching machine, a simultaneous biaxial stretching machine, and the like, but any suitable stretching machine can 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 still more preferably 30 μm to 65 μm.

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

  In one embodiment, the second retardation layer has a relationship in which the refractive index is 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, Re (550) is less than 10 nm. In another embodiment, the second retardation layer exhibits a relationship in which the refractive index is nx> ny. In this case, the in-plane retardation Re (550) of the second retardation layer is preferably 10 to 150, and more preferably 10 to 80.

  The second retardation layer can be formed of any appropriate material. A liquid crystal layer fixed in homeotropic alignment is preferable. The liquid crystal material (liquid crystal compound) that can be homeotropically aligned may be a liquid crystal monomer or a liquid crystal polymer. Specific examples of the liquid crystal compound and the method for forming the liquid crystal layer include the liquid crystal compounds and methods described in JP-A-2002-333642, [0020] to [0042]. 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. Laminate The in-plane retardation Re (550) of the laminate of the first retardation layer and the second retardation layer is 120 nm to 160 nm, preferably 130 nm to 150 nm. The thickness direction retardation Rth (550) of the laminate is 40 nm to 100 nm, preferably 60 nm to 80 nm. By setting the optical characteristics of the laminate in this way, the viewing angle characteristics can be improved and the change in display characteristics can be suppressed. In addition, a laminated body is obtained by laminating | stacking a 1st phase difference layer and a 2nd phase difference layer through arbitrary appropriate adhesive layers or adhesive bond layers.

A-5. Protective film The said protective film is formed with arbitrary appropriate films which can be used as a protective layer of a polarizer. Specific examples of the material as the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyester-based, polyvinyl alcohol-based, polycarbonate-based, polyamide-based, polyimide-based, polyethersulfone-based, and polysulfone-based materials. And transparent resins such as polystyrene, polynorbornene, polyolefin, (meth) acryl, and acetate. Further, thermosetting resins such as (meth) acrylic, urethane-based, (meth) acrylurethane-based, epoxy-based, and silicone-based or ultraviolet curable resins are also included. In addition to this, for example, a glassy polymer such as a siloxane polymer is also included. Moreover, the polymer film as described in Unexamined-Japanese-Patent No. 2001-343529 (WO01 / 37007) can also be used. As a material for this film, for example, a resin composition containing a thermoplastic resin having a substituted or unsubstituted imide group in the side chain and a thermoplastic resin having a substituted or unsubstituted phenyl group and nitrile group in the side chain For example, a resin composition having an alternating copolymer composed of isobutene and N-methylmaleimide and an acrylonitrile / styrene copolymer can be mentioned. The polymer film can be, for example, an extruded product of the resin composition.

  As said (meth) acrylic-type resin, Tg (glass transition temperature) becomes like this. Preferably it is 115 degreeC or more, More preferably, it is 120 degreeC or more, More preferably, it is 125 degreeC or more, Most preferably, it is 130 degreeC or more. It is because it can be excellent in durability. Although the upper limit of Tg of the said (meth) acrylic-type resin is not specifically limited, From viewpoints of a moldability etc., Preferably it is 170 degrees C or less.

As said (meth) acrylic-type resin, arbitrary appropriate (meth) acrylic-type resins can be employ | adopted within the range which does not impair the effect of this invention. For example, poly (meth) acrylic acid ester such as polymethyl methacrylate, methyl methacrylate- (meth) acrylic acid copolymer, methyl methacrylate- (meth) acrylic acid ester copolymer, methyl methacrylate-acrylic acid ester -(Meth) acrylic acid copolymer, (meth) acrylic acid methyl-styrene copolymer (MS resin, etc.), polymer having an alicyclic hydrocarbon group (for example, methyl methacrylate-cyclohexyl methacrylate copolymer) And methyl methacrylate- (meth) acrylate norbornyl copolymer). Preferably, poly (meth) acrylic acid C _1-6 alkyl such as poly (meth) acrylate methyl 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 (meth) acrylic resins having a ring structure in the molecule described in, for example, Acrypet VH and Acrypet VRL20A manufactured by Mitsubishi Rayon Co., Ltd., and JP-A-2004-70296. Examples of the resin include 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 in that it has high heat resistance, high transparency, and high mechanical strength.

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

  The (meth) acrylic resin having the 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 5,000 to 1,000,000, and still more preferably 10,000 to 500,000. Preferably it is 50000-500000.

  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, still more preferably 130 ° C. or higher, particularly preferably 135 ° C., most preferably. Is 140 ° C. or higher. It is because it can be excellent in durability. The upper limit of Tg of the (meth) acrylic resin having the lactone ring structure is not particularly limited, but is preferably 170 ° C. or less from the viewpoint of moldability and the like.

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

  The protective film 20 (first protective film 21) disposed on the opposite side of each retardation layer with respect to the polarizer has a surface such as a hard coat treatment, an antireflection treatment, an antisticking treatment, and an antiglare treatment as necessary. Processing may be performed. 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, and even more preferably 5 μm to 150 μm.

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

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

A-6. Others Arbitrary appropriate adhesive layers or adhesive layers are used for lamination | stacking of each layer which comprises the polarizing plate of this 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, an adhesive layer may be provided on the polarizing plate 100, 100 'on the second retardation layer 40 side. By providing the pressure-sensitive adhesive layer in advance, it can be easily bonded to another optical member (for example, an organic EL panel). In addition, it is preferable that the peeling film is bonded together on the surface of this adhesive layer until it uses.

B. Manufacturing Method Any appropriate method can be adopted as a manufacturing method of the polarizing plate. In one preferred embodiment, the longitudinal direction of the polarizer while conveying the elongated polarizer having an absorption axis in the longitudinal direction and the elongated first or second retardation layer in the longitudinal direction, respectively. And laminating so as to align the longitudinal direction of the retardation layer and obtaining a laminated film, while conveying the laminated film and the elongated second or first retardation layer in the longitudinal direction, And a step of laminating so that the longitudinal direction of the laminated film and the longitudinal direction of the retardation layer are aligned. A long retardation film and a long retardation film are produced by laminating a long first retardation layer and a long second retardation layer. You may manufacture by laminating | stacking. Here, the angle θ between 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, as described above. ° ≦ θ ≦ 52 °, more preferably 39 ° ≦ θ ≦ 51 °.

  The long first retardation layer has a slow axis in the direction of an angle θ with respect to the longitudinal direction. According to such a configuration, as described above, roll-to-roll is possible in manufacturing the polarizing plate, and the manufacturing process can be significantly shortened.

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

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

(1) Thickness The thickness 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, 550 nm, and the measurement temperature was 23 ° C.
Moreover, the average refractive index was measured using an Abbe refractometer manufactured by Atago Co., Ltd., and the refractive indexes nx, ny, and nz were calculated from the obtained retardation values.
(3) Phase difference variation by environmental test A sample was cut out from the phase difference film to 50 mm × 50 mm, and the phase difference was measured by Axoscan. Thereafter, the sample was allowed to stand in a constant temperature and humidity chamber at 40 ° C. and 90% RH for 100 hours, and then the phase difference was measured to evaluate the difference in phase difference before and after the environmental test.
(4) Water Absorption Rate Measured according to “Test method for water absorption rate and boiling water absorption rate of plastics” described in JIS K 7209. The size of the test piece was a square with a side of 50 mm, and was obtained by immersing the test piece in water at a water temperature of 25 ° C. for 24 hours and then measuring the weight change before and after the immersion. The unit is%.
(5) Reflection hue A black image was displayed on the obtained organic EL panel, and the reflection hue was measured using a viewing angle measurement evaluation apparatus conoscope manufactured by Auoronic-MERCHERS.

[Example 1]
(Production of polycarbonate resin film)
37.5 parts by mass of isosorbide (ISB), 91.5 parts by mass of 9,9- [4- (2-hydroxyethoxy) phenyl] fluorene (BHEPF), 8.4 parts by mass of polyethylene glycol (PEG) having an average molecular weight of 400, First, 105.7 parts by weight of diphenyl carbonate (DPC) and 0.594 parts by weight of cesium carbonate (0.2% by weight aqueous solution) as a catalyst were put in a reaction vessel, respectively, and the first stage of the reaction in 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 while stirring as necessary (about 15 minutes).

Next, the pressure in 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 increased to 190 ° C. over 1 hour.
After holding the reaction vessel temperature at 190 ° C. for 15 minutes, as a second step, the pressure in the reaction vessel is set to 6.67 kPa, and the heat medium temperature of the reaction vessel is increased to 230 ° C. in 15 minutes. The generated phenol was extracted 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, and the formed reaction product was extruded into water, and then pelletized to obtain BHEPF / ISB / PEG = 42.9 mol% / 52.8 mol% / 4.3. A polycarbonate resin A containing a structural unit derived from a dihydroxy compound at a mol% ratio was obtained.
The obtained polycarbonate resin A had a glass transition temperature of 126 ° C. and a reduced viscosity of 0.372 dL / g.

The obtained polycarbonate resin A was vacuum-dried at 80 ° C. for 5 hours, and then a single-screw extruder (manufactured by Isuzu Chemical Industries, screw diameter 25 mm, cylinder setting temperature: 220 ° C.), T die (width 300 mm, setting temperature: 220 [deg.] C.), a chill roll (set temperature: 120 to 130 [deg.] C.), and a film forming apparatus equipped with a winder, a polycarbonate resin film having a length of 3 m, a width of 300 mm, and a thickness of 120 [mu] m was produced.
The polycarbonate resin film obtained had a water absorption rate of 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 times using a lab stretcher KARO IV (manufactured by Bruckner) to obtain a retardation film. .
Re (550) of the obtained retardation film is 141 nm, Rth (550) is 141 nm (nx: 1.5969, ny: 1.5942, nz: 1.5942), and refractive index of nx> ny = nz. The characteristics are shown. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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) (numbers 65 and 35 in the formula indicate mol% of the monomer units and are represented by block polymer for convenience: weight average molecular weight 5000), Dissolve 80 parts by weight of a polymerizable liquid crystal exhibiting a nematic liquid crystal phase (manufactured by BASF: trade name Palicolor LC242) and 5 parts by weight of a photopolymerization initiator (trade name: Irgacure 907, manufactured by Ciba Specialty Chemicals) in 200 parts by weight of cyclopentanone Thus, a liquid crystal coating solution was prepared. And after apply | coating the said coating liquid to a base film (norbornene-type resin film: Nippon Zeon Co., Ltd. make, brand name "ZEONEX") with a bar coater, a liquid crystal is dried by heating at 80 degreeC for 4 minutes. Oriented. The liquid crystal layer was irradiated with ultraviolet rays to cure the liquid crystal layer, thereby forming a liquid crystal solidified layer (thickness: 0.58 μm) serving as the second retardation layer on the substrate. This layer has Re (550) of 0 nm and Rth (550) of -71 nm (nx: 1.5326, ny: 1.5326, nz: 1.6550), and exhibits a refractive index characteristic of nz> nx = ny. It was.

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

(Preparation of polarizing plate)
A triacetyl cellulose film (thickness 40 μm, manufactured by Konica Minolta, trade name “KC4UYW”) was bonded to one side of the polarizer via a polyvinyl alcohol-based adhesive.
The retardation film was bonded to the other side of the polarizer via a polyvinyl alcohol-based adhesive. Here, the retardation film was laminated so that the slow axis of the retardation film was 45 ° counterclockwise with respect to the absorption axis of the polarizer. Next, the liquid crystal solidified layer was bonded 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)
A pressure-sensitive adhesive layer was formed with an acrylic pressure-sensitive adhesive on the liquid crystal solidified layer (second retardation layer) side of the obtained polarizing plate, and cut into dimensions 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 paste the cut out polarizing plate together to make organic EL I got a panel.
Table 1 shows the measurement results of the reflection hue of this organic EL panel. In Table 1, “viewing angle characteristic” indicates the reflection hue in the front direction and the reflection hue in the oblique direction (maximum value or minimum value at 45 ° polar angle) on the xy chromaticity diagram of the CIE color system. The distance between two points Δxy is shown. In addition, “change in front hue Δxy” and “change in diagonal hue Δxy” indicate changes in reflected hue before and after the environmental test.

[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 draw ratio was 1.85 times.
Re (550) of the obtained retardation film is 120 nm, Rth (550) is 120 nm (nx: 1.5967, ny: 1.5944, nz: 1.5944), and refractive index of nx> ny = nz. The characteristics are shown. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 0.66 μm.
Re (550) of the obtained liquid crystal solidified layer is 0 nm, Rth (550) is −80 nm (nx: 1.5339, ny: 1.5339, nz: 1.6551), and ref>nz> nx = ny. The rate characteristics are shown.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 120 nm, and 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 draw ratio was 2.1 times.
Re (550) of the obtained retardation film is 160 nm, Rth (550) is 160 nm (nx: 1.5971, ny: 1.5940, nz: 1.5940), and refractive index of nx> ny = nz. The characteristics are shown. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 0.49 μm.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was −60 nm (nx: 1.5325, ny: 1.5325, nz: 1.6549), and ref>nz> nx = ny. The rate characteristics are shown.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 160 nm, and 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 (trade name “Pure Ace WR (EWF)” manufactured by Teijin Limited) 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 refractive index characteristics of nx> ny = nz. . Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the water absorption was 0.5%, and the phase difference variation by an environmental test was 5 nm.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film was used.
Re (550) of the obtained laminated body was 147 nm, and 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, polycarbonate resin B containing structural units derived from a dihydroxy compound at a ratio of BHEPF / ISB / PEG (average molecular weight 1000) = 45 mol% / 51 mol% / 4 mol% was obtained. The obtained polycarbonate resin B had a glass transition temperature of 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 polycarbonate resin film obtained had a water absorption of 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 longitudinal stretching was performed at a stretching ratio of 1.5. The obtained retardation film had Re (550) of 141 nm and Rth (550) of 141 nm, and exhibited a refractive index characteristic of nx> ny = nz. Further, Re (450) / Re (550) of the obtained retardation film was 0.98. Furthermore, the phase difference variation by an environmental test was 5 nm.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film was used.
Re (550) of the obtained laminated body was 141 nm, and 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 (water absorption rate: 3.2%) of Example 1 of JP-A-2005-42039 is used at a temperature of 100 ° C. and a magnification of 1.3 times using a laboratory stretcher KARO IV (manufactured by Bruckner). Simultaneously biaxial stretching was performed to obtain a retardation film.
Re (550) of the obtained retardation film is 0 nm, Rth (550) is 141 nm (nx: 1.4912, ny: 1.4912, nz: 1.4877), and refractive index of nx = ny> nz The characteristics are shown. Further, the water absorption was 3.2%, and the phase difference variation by an environmental test was 15 nm.

(Preparation of second retardation layer)
100 parts by weight of a liquid crystal compound [Dainippon Ink Chemical Co., Ltd., trade name “UCL-001”], 3 weights of photopolymerization initiator [Ciba Specialty Chemicals Co., Ltd., trade name “Irgacure 907”] A solution was prepared by dissolving a liquid crystalline composition mixed with 0.05 part by weight of a part and a leveling agent [trade name “BYK361” manufactured by Big Chemie Co., Ltd.] in 200 parts by weight of cyclopentanone (boiling point 131 ° C.). Next, 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 Co., Ltd., trade name “NH-18”. ]] Is uniformly applied in one direction using a rod coater, dried in an air-circulating constant temperature oven at 80 ° C. and 70 ° C. ± 1 ° C. for 5 minutes, and then a rubbing cloth having nylon pile yarn is used. Using the attached cylindrical roller, a lavink treatment (rotation speed 1000 rpm), pushing amount 0.30 mm, moving speed 60 mm / second) was performed to obtain an alignment substrate. After coating the prepared liquid crystal solution on the surface of the obtained alignment substrate using a rod coater, drying in an air circulation type constant temperature oven at 90 ° C. ± 1 ° C. for 3 minutes, and applying / drying The cured layer of the liquid crystalline composition was cured by UV irradiation and aligned in a homogeneous arrangement.
Re (550) of the obtained cured layer is 141 nm, Rth (550) is 141 nm (nx: 1.4916, ny: 1.4893, nz: 1.4893), and refractive index characteristics of nx> ny = nz showed that.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the 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 having a polymerization degree of 1800 (Nippon Synthetic Chemical, NH-18) dried at 105 ° C. for 2 hours was dissolved in 95 ml of DMSO. Mesitaldehyde 3.78g, propionaldehyde 1.81g and p-toluenesulfonic acid monohydrate 1.77g were added here, and it stirred at 40 degreeC for 4 hours. Reprecipitation was performed in a water / methanol = 2/1 solution in which 2.35 g of sodium bicarbonate was dissolved. The polymer obtained by filtration was dissolved in THF and reprecipitated in diethyl ether. After filtration and drying, 7.89 g of a white polymer was obtained. When the obtained polymer was measured under the above-described measurement conditions, the molar ratio 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. Obtained. The glass transition temperature of this polymer was 102 ° C. The obtained polymer was dissolved in DMF and formed into a film 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.
Re (550) of the obtained film is 141 nm, Rth (550) is 141 nm (nx: 1.5969, ny: 1.5942, nz: 1.5942), and the refractive index characteristics of nx> ny = nz are obtained. Indicated. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the water absorption was 4.9%, and the phase difference variation by an environmental test was 20 nm.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film was used.
Re (550) of the obtained laminated body was 141 nm, and 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 draw ratio was 1.82.
Re (550) of the obtained retardation film is 115 nm, Rth (550) is 115 nm (nx: 1.5966, ny: 1.5944, nz: 1.5944), and refractive index of nx> ny = nz. The characteristics are shown. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was −85 nm (nx: 1.5338, ny: 1.5338, nz: 1.6552), and nz> nx = ny refraction. The rate characteristics are shown.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 115 nm, and 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 draw ratio was 2.13.
Re (550) of the obtained retardation film is 170 nm, Rth (550) is 170 nm (nx: 1.5972, ny: 1.5939, nz: 1.5939), and refractive index of nx> ny = nz The characteristics are shown. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 0.49 μm.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was −60 nm (nx: 1.5325, ny: 1.5325, nz: 1.6549), and ref>nz> nx = ny. The rate characteristics are shown.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 170 nm, and 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 draw ratio was 1.7 times.
Re (550) of the obtained retardation film was 100 nm, Rth (550) was 100 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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, sufficiently washed with methanol, and dried at 80 ° C. to obtain a diisopropyl fumarate homopolymer. The obtained diisopropyl fumarate homopolymer was dissolved in a THF solution to give a 22% solution, and tris (2,4-di-) was used as a hindered phenol antioxidant for 100 parts by weight of the diisopropyl fumarate homopolymer. tert-butylphenyl) phosphite 0.35 parts by weight and pentaerythritol-tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) 0.15 parts by weight as a phosphorus-based antioxidant, After adding 1 part by weight of 2- (2H-benzotriazol-2-yl) -p-cresol as an ultraviolet absorber, it was cast on a support substrate of a solution casting apparatus by the T-die method, Films having a thickness of 20.7 μm were obtained, each dried at 120 ° C. for 15 minutes.
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 lab stretcher KARO IV (manufactured by Bruckner), and a retardation film was obtained. Obtained.
Re (550) of the obtained retardation film was 20 nm, Rth (550) was −60 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and 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. Re (550) of the obtained retardation film was 20 nm, Rth (550) was −40 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow 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.
Re (550) of the obtained laminated body was 120 nm, and 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. Re (550) of the obtained retardation film was 20 nm, Rth (550) was −40 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 160 nm, and 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 draw ratio was 2.2 times.
The obtained retardation film had Re (550) of 170 nm and Rth (550) of 170 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.025 and the thickness was 40 μm. Re (550) of the obtained retardation film was 10 nm, Rth (550) was -130 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow 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.
Re (550) of the obtained laminated body was 160 nm, and 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 commercial retardation film used in Example 4 was stretched at a fixed end at a stretching temperature of 190 ° C. (MD stretching ratio: 0.85 times, TD stretching ratio: 1.1 times) to form a first retardation layer retardation. A film was obtained.
Re (550) of the obtained retardation film was 100 nm, Rth (550) was 100 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an environmental test was 5 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and 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 retardation layer.
The obtained retardation film had Re (550) of 170 nm and Rth (550) of 170 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.025 and the thickness was 40 μm. Re (550) of the obtained retardation film was 10 nm, Rth (550) was -130 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow 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.
Re (550) of the obtained laminated body was 160 nm, and 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 draw ratio was 1.6.
The obtained retardation film had Re (550) of 90 nm and Rth (550) of 90 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an environmental test was 5 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 110 nm, and 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 draw ratio was 2.3 times.
The obtained retardation film had Re (550) of 180 nm and Rth (550) of 180 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.025 and the thickness was 40 μm. Re (550) of the obtained retardation film was 10 nm, Rth (550) was -130 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow 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.
Re (550) of the obtained laminated body was 170 nm, and 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 free end stretching at a stretch ratio of 1.2 was performed.
Re (550) of the obtained retardation film was 100 nm, Rth (550) was 100 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, the water absorption rate of the obtained retardation film was 3.2%, and the retardation fluctuation by an environmental test was 15 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and 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 in Comparative Example 3 except that the draw ratio was 1.28 times.
Re (550) of the obtained retardation film was 100 nm, Rth (550) was 100 nm, and exhibited refractive index characteristics of nx> ny = nz. Moreover, the water absorption rate of the obtained retardation film was 4.9%, and the retardation fluctuation by an environmental test was 20 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and 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 draw ratio was 2.2 times.
The obtained retardation film had Re (550) of 120 nm and Rth (550) of 130 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 0.75 μm.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was -90 nm, and the refractive index characteristic of nz> nx = ny was exhibited.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 120 nm, and 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was −30 nm, and exhibited a refractive index characteristic of nz> nx = ny.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 120 nm, and 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 obtained retardation film had Re (550) of 160 nm and Rth (550) of 380 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was -280 nm, and the refractive index characteristic of nz> nx = ny was exhibited.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 160 nm, and 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 draw ratio was 2.6 times.
The obtained retardation film had Re (550) of 160 nm and Rth (550) of 170 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 1.07 μm.
The obtained liquid crystal solidified layer had Re (550) of 0 nm, Rth (550) of -130 nm, and exhibited a refractive index characteristic of nz> nx = ny.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 160 nm, and 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 stretch ratio 0.85 times, TD stretch ratio 1.1 times), and then fixed-end stretched (MD stretch ratio 1). .1 times) to obtain a first retardation film for retardation layer.
The obtained retardation film had Re (550) of 120 nm and Rth (550) of 130 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was -90 nm, and the refractive index characteristic of nz> nx = ny was exhibited.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 120 nm, and 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 obtained retardation film had Re (550) of 160 nm and Rth (550) of 170 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 1.07 μm.
The obtained liquid crystal solidified layer had Re (550) of 0 nm, Rth (550) of -130 nm, and exhibited a refractive index characteristic of nz> nx = ny.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 160 nm, and 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 draw ratio was 2.25 times.
Re (550) of the obtained retardation film was 130 nm, Rth (550) was 141 nm, and the refractive index characteristic of nx>ny> nz was shown. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was −30 nm, and exhibited a refractive index characteristic of nz> nx = ny.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 130 nm, and 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 draw ratio was 2.5.
The obtained retardation film had Re (550) of 150 nm and Rth (550) of 181 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 1.33 μm.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was -160 nm, and exhibited refractive index characteristics of nz> nx = ny.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 150 nm, and 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 at a MD stretching ratio of 1.3 was performed.
The obtained retardation film had Re (550) of 120 nm and Rth (550) of 130 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, the water absorption rate of the obtained retardation film was 3.2%, and the retardation fluctuation by an environmental test was 15 nm.

(Preparation of second retardation layer)
Thickness: 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was -90 nm, and the refractive index characteristic of nz> nx = ny was exhibited.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 120 nm, and 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 at 2.3 times the MD stretching ratio was performed.
The obtained retardation film had Re (550) of 120 nm and Rth (550) of 130 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, the water absorption rate of the obtained retardation film was 4.9%, and the retardation fluctuation by an environmental test was 20 nm.

(Preparation of second retardation layer)
Thickness: 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.
Re (550) of the obtained liquid crystal solidified layer was 0 nm, Rth (550) was -90 nm, and the refractive index characteristic of nz> nx = ny was exhibited.

(Production of laminate)
A laminate was obtained in the same manner as in Example 1 except that the above retardation film and liquid crystal solidified layer were used.
Re (550) of the obtained laminated body was 120 nm, and 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 sequential biaxial stretching (fixed end stretching at an MD stretching ratio of 1.6 times and then transverse stretching at a TD stretching ratio of 1.26 times) was performed.
The obtained retardation film had Re (550) of 40 nm and Rth (550) of 100 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.2 times and the thickness was 41 μm. Re (550) of the obtained retardation film was 80 nm, Rth (550) was −60 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Examples except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. 1 to obtain a laminate.
Re (550) of the obtained laminated body was 120 nm, and 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 sequential biaxial stretching (fixed end stretching at an MD stretching ratio of 2.7 times and then lateral stretching at a TD stretching ratio of 1.1 times) was performed.
The obtained retardation film had Re (550) of 160 nm and Rth (550) of 180 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.1 times and the thickness was 35 μm. Re (550) of obtained retardation film was 40 nm, Rth (550) was -80 nm, and showed the refractive index characteristic of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and 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 sequential biaxial stretching (fixed end stretching at an MD stretching ratio of 1.65 times and then lateral stretching at a TD stretching ratio of 1.31 times) was performed.
The obtained retardation film had Re (550) of 40 nm and Rth (550) of 120 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.3 times and the thickness was 41 μm. Re (550) of the obtained retardation film was 120 nm, Rth (550) was −20 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Examples except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. 1 to obtain a laminate.
Re (550) of the obtained laminated body was 160 nm, and 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 was stretched at an MD stretch ratio of 2.75.
The obtained retardation film had Re (550) of 170 nm and Rth (550) of 180 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.025 and the thickness was 45.5 μm. Re (550) of the obtained retardation film was 10 nm, Rth (550) was -140 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 160 nm, and 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 for retardation layer. A film was obtained.
The obtained retardation film had Re (550) of 40 nm and Rth (550) of 100 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an environmental test was 5 nm.

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

(Production of laminate)
Examples except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. 1 to obtain a laminate.
Re (550) of the obtained laminated body was 120 nm, and 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 times to obtain a first retardation film for retardation layer.
The obtained retardation film had Re (550) of 170 nm and Rth (550) of 180 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an environmental test was 5 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 160 nm, and 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 sequential biaxial stretching (fixed end stretching at an MD stretching ratio of 1.65 times and then lateral stretching at a TD stretching ratio of 1.3 times) was performed.
The obtained retardation film had Re (550) of 50 nm and Rth (550) of 125 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.2 times and the thickness was 50 μm. Re (550) of the obtained retardation film was 80 nm, Rth (550) was -90 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Examples except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. 1 to obtain a laminate.
Re (550) of the obtained laminated body was 130 nm, and 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 was stretched at an MD stretch ratio of 2.8.
The obtained retardation film had Re (550) of 180 nm and Rth (550) of 190 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, Re (450) / Re (550) of the obtained retardation film was 0.89. Furthermore, the phase difference variation by an 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 draw ratio was 1.025 and the thickness was 26.6 μm. Re (550) of the obtained retardation film was 10 nm, Rth (550) was −80 nm, and exhibited refractive index characteristics of nz>nx> ny.

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged so as to be substantially orthogonal to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 170 nm, and 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 sequential biaxial stretching (free end stretching at an MD stretching ratio of 1.18 times and then lateral stretching at a TD stretching ratio of 1.08 times) was performed.
The obtained retardation film had Re (550) of 40 nm and Rth (550) of 100 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, the water absorption rate of the obtained retardation film was 3.2%, and the retardation fluctuation by an environmental test was 15 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and 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 Comparative Example 3 except that sequential biaxial stretching (fixed end stretching at an MD stretching ratio of 1.96) and lateral stretching at a TD stretching ratio of 1.37 was performed.
The obtained retardation film had Re (550) of 40 nm and Rth (550) of 100 nm, and exhibited refractive index characteristics of nx>ny> nz. Moreover, the water absorption rate of the obtained retardation film was 4.9%, and the retardation fluctuation by an environmental test was 20 nm.

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

(Production of laminate)
Example 1 except that each of the above retardation films was used and that the slow axis of the first retardation layer and the slow axis of the second retardation layer were arranged substantially parallel to each other. In the same manner, a laminate was obtained.
Re (550) of the obtained laminated body was 120 nm, and Rth (550) was 40 nm.

  In each of the examples, the viewing angle characteristics were favorable below 0.07, and the hue change Δxy in both the front and oblique directions was good below 0.07. In a comparative example in which the water absorption rate 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 scope of the present invention. At least one of the viewing angle characteristics, the front hue change Δxy, and the oblique hue change Δxy was insufficient.

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

DESCRIPTION OF SYMBOLS 10 Polarizer 20 Protective film 21 1st protective film 22 2nd protective film 30 1st phase difference layer 40 2nd phase difference layer 100 Polarizing plate 100 'Polarizing plate

Claims (7)

A polarizer, a first retardation layer, and a second retardation layer;
The first retardation layer exhibits a refractive index characteristic of nx> ny = nz and satisfies a relationship of Re (450) <Re (550);
The second retardation layer exhibits a refractive index characteristic of nz> nx ≧ ny,
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, and Rth (550) is 40 nm to 100 nm,
The water absorption of the first retardation layer is 3% or less,
Used for 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. Represents the retardation in the thickness direction.   The polarizing plate according to claim 1, wherein an optically 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, a substituted or unsubstituted carbon atom having 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, 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 claim 1, 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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