TWI425024B - A retardation film, a method for manufacturing the same, and a polarizing plate - Google Patents

Description

Phase difference film, method of manufacturing the same, and polarizing plate

The present invention relates to a retardation film made of a cyclic olefin polymer, a method for producing the same, and a polarizing plate using the retardation film.

The cyclic olefin resin is high in glass transition temperature due to the rigidity of the main chain structure, and has a bulky group in the main chain structure, so that it has an amorphous property and a high light transmittance, and has a refractive index. The characteristics of low anisotropy and low birefringence are attracting attention as a transparent thermoplastic resin having excellent heat resistance, transparency, and optical properties.

In recent years, the above-mentioned cyclic olefin-based resin has been studied in the field of optical materials such as optical disks, optical lenses, and optical fibers, and sealing materials such as optical semiconductor seals. Moreover, it has been attempted to apply to an optical film, and the problem of the conventional optical film is improved as follows.

Conventionally, a film such as polycarbonate, polyester, or cellulose triacetate used as an optical film has a large photoelastic coefficient, so that a phase difference appears and changes due to a slight stress change, and heat resistance or water absorption deformation occurs. There is a problem such as poorness, and a film made of a cyclic olefin resin is proposed as various films for optics. For example, Patent Literatures 1 and 2 describe a phase difference plate made of a film of a cyclic olefin resin. Further, in Patent Documents 3 to 5, a protective film in which a film of a cyclic olefin resin is used for a polarizing plate is described.

In these publications, the film water absorption rate of the cyclic olefin resin is described. It is 0.05% or less, and it is intended to describe that this low water absorption property is excellent. However, when the film of the low-water-absorbent cyclic olefin-based resin is used as a retardation film or a substrate for a liquid crystal display element, for example, adhesion to a hard coat layer, an antireflection film or a transparent conductive layer, or There is a problem with the adhesion of the polarizing plate or the glass. Further, when used as a protective film for a polarizing plate, in addition to the above problems, the moisture permeability is also low as in the case of the water absorption rate, so that the water of the water-based adhesive generally used is difficult to dry when it is bonded to the polarizing film. problem.

On the other hand, many kinds of cyclic olefin-based resins are known, and not all of the cyclic olefin-based resins have a water absorption ratio of 0.05% or less. In order to make the water absorption rate to be 0.05% or less, it is necessary for a cyclic olefin-based resin to have a structure containing a polyolefin structure or a halogen formed only of a carbon atom and a hydrogen atom.

Therefore, in order to solve the problem of the above-mentioned low water absorption, an optical film containing a cyclic olefin resin in which a polar group is introduced in a molecule is described in Patent Documents 6 to 7. These optical films have high transparency, low phase difference in transmitted light, and excellent optical characteristics such as uniformity and stable phase difference in the extended alignment, and are heat resistance, adhesion to other materials, or adhesion. It is excellent in properties and the like, and has the advantages of small water absorption deformation, and is used in many liquid crystal display elements.

However, with the recent increase in the size of liquid crystal display elements, improvement in brightness contrast, and improvement in viewing angle visibility, it is desirable that the optical film used does not disturb the visibility of the doodle image, and is more uniform or stable. Sex. Therefore, a retardation film and a polarizing plate which are excellent in bonding with a polarizing film are further desired. For example, Patent Document 8 and the like describe a polarizing plate that reduces warpage after bonding a protective film, but is a protective film that defines both sides of the polarizing film. The combination is problematic in manufacturing and installation of liquid crystal display elements, and further improvement is desired.

[Patent Document 1] Japanese Patent Laid-Open No. Hei 5-2108

[Patent Document 2] Japanese Patent Laid-Open No. Hei 5-64865

[Patent Document 3] Japanese Patent Laid-Open No. Hei 5-212828

[Patent Document 4] Japanese Patent Laid-Open No. Hei 6-51117

[Patent Document 5] Japanese Patent Laid-Open No. Hei 7-77608

[Patent Document 6] Japanese Patent Laid-Open No. Hei 7-287122

[Patent Document 7] Japanese Patent Laid-Open No. Hei 7-287123

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2005-215700

The present invention provides a retardation film having a NZ coefficient close to 1, a warpage after bonding with a polarizing film, and a method for producing the same, and a polarizing plate using the film.

The retardation film of the present invention is formed of a cyclic olefin polymer and is characterized by satisfying the following formulas (1) to (5).

(1) 70nm≦Re≦300nm

(2) 1.1 ≦ ≦ ≦ 1.7 (In the formulas (1) to (2), Re is the in-plane phase difference of the film at a wavelength of 589 nm, expressed by Re = (nx - ny) × d, and NZ is NZ = ( Nx -nz)/(nx-ny) represents a coefficient; wherein nx is the maximum refractive index in the plane of the film, ny is the refractive index perpendicular to the direction of nx in the plane of the film, and nz is perpendicular to nx and ny. The refractive index of the intersecting film thickness direction, d indicates the thickness (nm) of the film, and (3) α (MD) ≦ 90 ppm / ° C

(4) α (TD) ≦ 90ppm / ° C

(5)| α(MD)-α(TD)|≦30ppm/°C (in equations (3) to (5), α(MD) is expressed as the average linear expansion coefficient in the longitudinal direction of the film, α(TD) The average linear expansion coefficient in the width direction of the film; however, the average linear expansion coefficient is any value from -40 ° C to 85 ° C).

In the retardation film of the present invention, the cyclic olefin polymer is preferably a structural unit represented by the following formula (I).

[In the formula (I), m is an integer of 1 or more; p is an integer of 0 or more; D is a group represented by -CH=CH- or -CH ₂ CH ₂ -; and R ¹ to R ⁴ are each independently The ground represents a hydrogen atom, a halogen atom, a bond group containing an oxygen atom, a sulfur atom, a nitrogen atom or a ruthenium atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or an atom or a group selected from a group consisting of a polar group. R ¹ and R ² may be integrated to form a divalent hydrocarbon group, and R ³ and R ⁴ may be integrated to form a divalent hydrocarbon group; R ¹ and R ² may be bonded to each other to form a carbocyclic or heterocyclic ring, R ³ and R ^{4 ;} They may also be bonded to each other to form a carbocyclic or heterocyclic ring, which may be monocyclic or polycyclic].

The retardation film of the present invention has a thickness of 20 to 100 μm, and the difference between the maximum thickness and the minimum thickness of the film is preferably 3 μm or less.

The method for producing a retardation film of the present invention is characterized in that a film having a thickness of 100 to 250 μm and a difference between a maximum thickness and a minimum thickness of the film of 3 μm is a cyclic olefin polymer film (raw film) The film) is laterally uniaxially stretched in such a manner that the stretching ratio is 2.5 to 5.5 times, and the retardation film is obtained.

The polarizing plate of the present invention is characterized in that the retardation film is laminated on at least one side of the polarizing film.

When the retardation film formed of the cyclic olefin polymer of the present invention is laterally stretched at a stretching ratio of 2.5 to 5.5 times, a film having a NZ coefficient close to one and a small warpage after bonding with the polarizing film can be obtained, and is suitable for use in Vertical alignment type liquid crystal display element.

[Best Mode for Carrying Out the Invention]

Hereinafter, the present invention will be specifically described.

<phase difference film>

The retardation film of the present invention is formed of a cyclic olefin polymer and satisfies the following formulas (1) to (5).

(1) 70nm≦Re≦300nm

(2) 1.1 ≦ ≦ ≦ 1.7 (In the formulas (1) to (2), Re is the in-plane phase difference of the film at a wavelength of 589 nm, expressed by Re = (nx - ny) × d, and NZ is NZ = ( Nx-nz)/(nx-ny) represents a coefficient; wherein nx is the maximum refractive index in the plane of the film, ny is the refractive index perpendicular to the direction of nx in the plane of the film, and nz is relative to nx and ny. The refractive index in the thickness direction of the film perpendicularly intersected, d is the thickness (nm) of the film, and (3) α (MD) ≦ 90 ppm / ° C

(4) α (TD) ≦ 90ppm / ° C

(5)| α(MD)-α(TD)|≦30ppm/°C (in equations (3) to (5), α(MD) is expressed as the average linear expansion coefficient in the longitudinal direction of the film, α(TD) The average linear expansion coefficient in the width direction of the film; however, the average linear expansion coefficient is any value from -40 ° C to 85 ° C).

(1) and (2) are optical characteristics which affect the performance of the viewing angle compensation of the liquid crystal element, and are preferably different depending on the type or display form of the liquid crystal used in the liquid crystal element, and (1) Re The value is to prevent light leakage when viewed from the oblique direction in the black display of the liquid crystal element, and it is preferably 75 nm to 200 nm and more preferably 75 nm to 150 nm for obtaining a good viewing angle compensation. (2) The value of NZ is preferably approximately 1 for the viewing angle compensation of the vertical alignment type liquid crystal element, preferably 1.1 to 1.5, more preferably 1.1~1.4.

Further, when the viewing angle compensation of the vertical alignment type liquid crystal element is performed by using the polarizing plate of the present invention, a phase difference layer of Re ≦ 60 nm and NZ ≧ 3 is provided on one side of the polarizing plate, and it is preferable to perform good viewing angle compensation. . (The definition of the in-plane phase difference Re and NZ of the retardation layer is as described above, nx is the maximum refractive index in the phase difference layer, and ny is the refractive index perpendicularly intersecting in the direction of nx in the phase difference layer. Zn is a refractive index in the thickness direction of the retardation layer perpendicular to nx and ny, and d (nm) indicates the thickness of the retardation layer.

Both (3) and (4) mean that the value of α is small, and the dimensional change due to temperature changes is small. However, in addition to high heat-resistant resins such as polyimine, polyether oxime, and polyphenylene sulfide, a general thermoplastic resin has a linear expansion coefficient higher than that of glass or metal, and a linear expansion coefficient cannot be obtained by a resin alone. Close to zero. Further, there is a possibility that the polyvinyl alcohol constituting the polarizing plate or the like loses balance with the dimensional change of other resins, and the lower the coefficient of linear expansion, the better. However, a certain dimensional change is caused by the warming of the polarizing plate during drying, which makes the warpage or bending poor. Therefore, α (MD) and α (TD) are more practically 30 ppm/° C. to 90 ppm/° C.

(5) shows the anisotropy of the dimensional change due to temperature change. The larger the difference between α (MD) and α (TD), the larger the difference in the amount of dimensional change due to the direction of the film, and the more likely the warpage is. Preferably, α α (MD) α α (TD) | ≦ 25 ppm / ° C, more preferably | α (MD) - α (TD) | ≦ 20 ppm / ° C.

<Cyclic olefin polymer>

The cyclic olefin polymer to be used in the present invention is not particularly limited, and examples thereof include a ring-opening (co)polymer of a cyclic olefin monomer represented by the following formula (I') and formula (II'). A hydrogenated product of the ring-opening (co)polymer, an addition (co)polymer, an addition copolymer of a cyclic olefin monomer and an α-olefin, and the like. Among these, a hydrogenated product of a ring-opened (co)polymer is preferable, and a polymer having a structural unit represented by the following formula (I) is particularly preferable. The polymer may be a homopolymer having a structural unit represented by the following formula (I), or a copolymer having a structural unit represented by the formula (I) and the following formula (II). .

[In the formula (I), m is an integer of 1 or more; p is an integer of 0 or more; D is a group represented by -CH=CH- or -CH ₂ CH ₂ -; and R ¹ to R ⁴ are each independently The ground represents a hydrogen atom, a halogen atom, a bond group containing an oxygen atom, a sulfur atom, a nitrogen atom or a ruthenium atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or an atom or a group selected from a group consisting of a polar group. R ¹ and R ² may be integrated to form a divalent hydrocarbon group, and R ³ and R ⁴ may be integrated to form a divalent hydrocarbon group; R ¹ and R ² may be bonded to each other to form a carbocyclic or heterocyclic ring, R ³ and R ^{4 ;} They may also be bonded to each other to form a carbocyclic or heterocyclic ring, which may be monocyclic or polycyclic]. [In the formula (II), E is independently a group represented by -CH=CH- or -CH ₂ CH ₂ -; and R ⁵ to R ⁸ each independently represent a hydrogen atom, a halogen atom, an oxygen atom, and sulfur. a bond of an atom, a nitrogen atom or a halogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, a polar group; R ⁵ and R ⁶ may be integrated to form a divalent hydrocarbon group, and R ⁷ and R ⁸ may be integrated. A divalent hydrocarbon group is formed; R ⁵ or R ⁶ , and R ⁷ or R ⁸ may be bonded to each other to form a carbocyclic or heterocyclic ring, and the carbocyclic or heterocyclic ring may be a monocyclic structure or a polycyclic structure. ]

The glass transition temperature of the cyclic olefin polymer is in a field suitable for film processing, and the birefringence control property is ensured. The m system in the above formula (I) is preferably from 1 to 5, more preferably from 1 to 3, Further preferably, the ratio is 1 to 2; the p system is preferably 0 to 4, more preferably 0 to 2, and further preferably 0 to 1. Further, the number of carbon atoms of R ¹ to R ⁴ is preferably from 1 to 25, more preferably from 1 to 20, still more preferably from 1 to 10. Further, the number of carbon atoms of R ⁵ to R ^{8 in} the above formula (II) is preferably from 1 to 25, more preferably from 1 to 20, still more preferably from 1 to 10.

Production method

The cyclic olefin polymer of the present invention is a structural unit represented by the above formula (I) and, if necessary, a structural unit represented by the above formula (II).

The structural unit represented by the above formula (I) is derived from a cyclic olefin monomer represented by the following formula (I') by ring-opening (co)polymerization.

(In the formula (I'), m, p and R ¹ to R ⁴ are the same as those of the above formula (I).)

In the formula (I) or the formula (I'), examples of the polar group include a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, a carbonyloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, a cyano group, and a decylamine. A group, a quinone imine group, a triorganodecyloxy group, a triorganoalkylene group, an amine group, a fluorenyl group, an alkoxyalkyl group, a sulfonyl group, a carboxyl group, and the like. More specifically, examples of the alkoxy group include a methoxy group and an ethoxy group; and examples of the carbonyloxy group include an alkylcarbonyloxy group such as an ethoxylated group or a propyloxy group, and a benzene group. An arylcarbonyloxy group such as a mercaptooxy group; an alkoxycarbonyl group; for example, a methoxycarbonyl group or an ethoxycarbonyl group; and an aryloxycarbonyl group, for example, a phenoxycarbonyl group or a naphthyloxycarbonyl group; And a methoxycarbonyl group, a biphenyloxycarbonyl group, etc.; as a triorganosalkoxy group, a trimethyl decyloxy group, a triethyl decyloxy group, etc. a decyl group, a triethyl decyl group, etc.; as an amine group, The first-stage amine group is exemplified, and examples of the alkoxyalkylene group include a trimethoxydecylalkyl group and a triethoxydecylalkyl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

Examples of the hydrocarbon group having 1 to 10 carbon atoms include an alkyl group such as a methyl group, an ethyl group or a propyl group; a cycloalkyl group such as a cyclopentyl group or a cyclohexyl group; and an alkene such as a vinyl group, an allyl group or a propylene group. Base.

Further, the substituted or unsubstituted hydrocarbon group may be bonded directly to the ring structure or may be bonded via a linkage. Examples of the binding group include a hydrocarbon group having a valence of from 1 to 10 carbon atoms (for example, an alkylene group represented by -(CH ₂ ) _m - (wherein, m is an integer of from 1 to 10), and oxygen is contained. a combination of nitrogen, sulfur or hydrazine (for example, carbonyl (-CO-), oxycarbonyl (-O(CO)-), sulfonic acid (-SO ₂ -), ether linkage (-O-), sulfur Ether bond (-S-), imine group (-NH-), guanamine bond (-NHCO-, -CONH-), oxime bond (-OSi(R ₂ )- (where R is A The alkyl group such as a group or an ethyl group)) may be a complex group containing a plurality of these groups.

Specific examples of the cyclic olefin monomer (I') include the following compounds.

Tetracycline [4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, pentacyclic [6.5.1.1 ^3,6 .0 ^2,7 .0 ^9,13 ]-4-pentadecene, 8-methyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-ethyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-12 Alkene, 8-methoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-ethoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-n-propoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-isopropoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-n-butoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-methyl- 8-methoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-methyl-8-ethoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-methyl-8-n-propoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-methyl- 8-isopropoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-methyl-8-n-butoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-cyanotetracycline [4.4.0.1 ^2,5 .1 ^7,10 ]- 3-dodecene, 8-cyano-8-methyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-ethylenetetracycline [4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-phenyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-fluorotetracyclo[4.4.0.1 ^{2, 5} .1 ^7,10 ]-3-dodecene, 8-fluoromethyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-difluoromethyltetracycline [ 4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-trifluoromethyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-五Fluoroethyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8-difluorotetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3- ^Te Diene, 8,9-difluorotetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8-bis(trifluoromethyl)tetracyclo[4.4.0.1 ^{2, 5} .1 ^7,10 ]-3-dodecene, 8,9-bis(trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-armene -8-trifluoromethyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8,9-trifluorotetracycline [4.4.0.1 ^2,5 .1 ^{7 , 10} ]-3-dodecene, 8,8,9-paran (trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8,9 , 9-tetrafluorotetracycline [4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8,9,9-fluorene (trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-10 Diene, 8,8-difluoro-9,9-bis(trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,9-difluoro- 8,9-bis(trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8,9-trifluoro-9-trifluoromethyltetracyclic [4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8,9-trifluoro-9-trifluoromethoxytetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,8,9-trifluoro-9-pentafluoropropoxytetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-fluoro- 8-pentafluoroethyl-9,9-bis(trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,9-difluoro-8-seven Fluoroisopropyl-9-trifluoromethyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-chloro-8,9,9-trifluorotetracycline [4.4. 0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8,9-dichloro-8,9-bis(trifluoromethyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ] 3-dodecene, 8-(2,2,2-trifluoroethoxycarbonyl)tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene, 8-methyl- 8-(2,2,2-trifluoroethoxy Carbonyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene.

These may be used alone or in combination of two or more.

In the present invention, the structural unit represented by the above formula (I) preferably has a polar group, and the polar group thereof is preferably a group represented by the following formula (III). In other words, the structural unit represented by the above formula (I) or the cyclic olefin monomer represented by the above formula (I') is at least one of R ¹ to R ⁴ and is represented by the following formula (III). The base is good.

-(CH ₂ ) _n COOR' (III) (in the formula (III), n is an integer of 0 or 1 to 5; and R' is a hydrocarbon group having 1 to 15 carbon atoms.)

In the above formula (III), the smaller the value of n, the smaller the carbon number of R', the higher the glass transition temperature of the obtained copolymer, and the better the heat resistance. That is, n is generally 0 or an integer of 1 to 5, preferably 0 or 1, particularly preferably 0. Further, R' is usually a hydrocarbon group having 1 to 15 carbon atoms, but is preferably An alkyl group having 1 to 3 carbon atoms, more preferably an alkyl group having 1 to 2 carbon atoms is preferred.

Further, in the above formula (I) or (I'), when the polar group-bonded carbon atom represented by the above formula (III) further has a bonded alkyl group, the heat resistance of the obtained copolymer is sought It is better in balance with water absorption (wet).

Further, the number of carbon atoms of the alkyl group is preferably from 1 to 5, more preferably from 1 to 2, particularly preferably 1.

The structural unit represented by the above formula (II) is derived from a cyclic olefin monomer (II) represented by the following formula (II') via ring-opening copolymerization.

(In the formula (II'), R ⁵ to R ^{8 are the} same as the above formula (II).)

Specific examples of such a cyclic olefin monomer include the following compounds.

Tricyclo[4.3.0.1 ^2,5 ]癸-3,7-diene, bicyclo[2.2.1]hept-2-ene, bicyclo[2.2.1]heptane-2,5-diene, 5-methyl Bicyclo[2.2.1]hept-2-ene, 5-ethylbicyclo[2.2.1]hept-2-ene, 5-propylbicyclo[2.2.1]hept-2-ene, 5-butylbicyclo[ 2.2.1] hept-2-ene, 5-pentylbicyclo[2.2.1]hept-2-ene, 5-hexylbicyclo[2.2.1]hept-2-ene, 5-heptylbicyclo[2.2.1 Hept-2-ene, 5-octylbicyclo[2.2.1]hept-2-ene, 5-nonylbicyclo[2.2.1]hept-2-ene, 5-nonylbicyclo[2.2.1]g 2-ene, 5-indenylbicyclo[2.2.1]hept-2-ene, 5-dodecylbicyclo[2.2.1]hept-2-ene, 5-tridecylbicyclo[2.2. 1]hept-2-ene, 5-tetradecylbicyclo[2.2.1]hept-2-ene, 5-pentadecylbicyclo[2.2.1]hept-2-ene, 5-hexadecyl Bicyclo[2.2.1]hept-2-ene, 5-heptadecylbicyclo[2.2.1]hept-2-ene, 5-octadecylbicyclo[2.2.1]hept-2-ene, 5- Ninedecylbicyclo[2.2.1]hept-2-ene, 5-epicocyclobicyclo[2.2.1]hept-2-ene, 5-phenylbicyclobicyclo[2.2.1]hept-2-ene 5-cyanobicyclo [2.2.1] Hept-2-ene, 5-methoxycarbonylbicyclo[2.2.1]hept-2-ene, 5-ethoxycarbonylbicyclo[2.2.1]hept-2-ene, 5-A Oxycarbonyl-5-methylbicyclo[2.2.1]hept-2-ene, 5-ethoxycarbonyl-5-methylbicyclo[2.2.1]hept-2-ene, 5-cyano-5-methyl Bicyclo[2.2.1]hept-2-ene 5-ethylenebicyclo[2.2.1]hept-2-ene snail [茀-9,8'-tricyclo[4.3.0.1 ^2.5 ][3]decene ].

These may be used alone or in combination of two or more. In the present invention, bicyclo [2.2.1] hept-2-ene or tricyclo [4.3.0.1 ^2,5 ] 癸-3,7-diene is preferably used.

The cyclic olefin polymer of the present invention can be produced by subjecting one or more kinds of the cyclic olefin monomer (I') and the cyclic olefin monomer (II') to ring-opening copolymerization. The cyclic olefin polymer of the present invention has heat resistance and moderate water absorbability, so 8-methyl-8-methoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3 Copolymers of dodecene and bicyclo [2.2.1] hept-2-ene are especially preferred.

In the present invention, the copolymerization ratio of the cyclic olefin monomer (the compound represented by the formula (I')) and the cyclic olefin monomer (the compound represented by the formula (II')) is the sum of these In the case of 100 parts by weight, the cyclic olefin monomer (II') is usually preferably from 0 to 40 parts by weight, preferably from 3 to 30 parts by weight. When the copolymerization ratio of the cyclic olefin monomer (II') exceeds 30 parts by weight, the glass transition temperature is lowered, and the heat stability of the properties of the film such as a phase difference or a size is lowered. Moreover, the slidability, toughness, elongation workability, and phase difference developability of the obtained molded article, film, or sheet are less than 3 parts by weight.

In the present invention, in addition to the cyclic olefin monomers (I') and (II'), other cyclic olefin monomers or other cyclic olefin monomers may be used insofar as the object of the present invention is not impaired. The other monomer which can be copolymerized is used in a small amount as a copolymerization raw material monomer, and the cyclic olefin polymer of the present invention may contain a structural unit other than the structural unit represented by the above formulas (I) and (II). The structure The unit is a ring-opening copolymerization of a cyclic olefin monomer such as cyclobutene, cyclopentene, cycloheptene or cyclooctene together with the above cyclic olefin monomers (I') and (II'). To form. Further, in the main chain of polybutadiene, polyisoprene, styrene-butadiene copolymer, ethylene-nonconjugated diene copolymer, polynorbornene, etc., having olefinic unsaturation The cyclic olefin-based monomers (I') and (II') may be formed by ring-opening copolymerization in the presence of a bonded unsaturated hydrocarbon-based polymer or the like, and the present invention may be obtained by the ring-opening copolymerization. The impact resistance of the copolymer has a tendency to be improved.

However, in the present invention, it is preferred to carry out copolymerization using only the cyclic olefin monomers (I') and (II'). In other words, the cyclic olefin polymer of the present invention may have other structural units in addition to the structural units represented by the above formulas (I) and (II) without departing from the object of the present invention. It is preferable to have a structural unit other than the structural unit represented by the above formulas (I) and (II).

The ring-opening copolymer in which each of the cyclic olefin monomers is subjected to ring-opening copolymerization has an olefinic unsaturated bond in its molecule, and the olefinic unsaturated bond is hydrogenated because of problems such as heat-resistant coloring. Preferably, the hydrogenation reaction can also be applied to a known method.

For example, the catalyst, solvent, temperature conditions, and the like described in the Japanese Patent Application Laid-Open No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. Therefore, ring-opening polymerization and hydrogenation can be carried out.

The hydrogenation ratio of the olefinic unsaturated bond is generally 80% by mole or more, preferably 90% by mole or more, and more preferably 95% by mole or more. It is ideal for 99% or more. In the hydrogenation reaction of the present invention, the olefinic unsaturated bond of the present invention has an aromatic group based on the olefinic unsaturated bond in the molecule, and the aromatic is based on a refractive index or the like. Optical properties or heat resistance also work favorably and do not necessarily need to be hydrogenated.

The molecular weight of the cyclic olefin polymer of the present invention is a polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC), and is generally 3 × 10 ³ to 5 × 10 ^{5 .} Preferably, it is 5 × 10 ³ to 3 × 10 ⁵ , further preferably 1 × 10 ⁴ to 2 × 10 ⁵ , and the weight average molecular weight (Mw) in terms of polystyrene is generally 5 × 10 ³ -1 It is preferably in the range of ×10 ⁶ , preferably 1 × 10 ⁴ to 5 × 10 ⁵ , more preferably 2 × 10 ⁴ to 4 × 10 ⁵ .

When the molecular weight is too small, the strength of the obtained film is low, and the phase difference exhibitability during stretching processing is lowered. On the other hand, in the case where the molecular weight is too large, the solution viscosity or the melt viscosity becomes too high, and the productivity or workability of the copolymer of the present invention is deteriorated.

Further, the molecular weight distribution (Mw/Mn) of the cyclic olefin polymer of the present invention is usually 1.5 to 10, preferably 2 to 7, and more preferably 2 to 5.

The cyclic olefin polymer of the present invention has a saturated water absorption at 23 ° C of generally 0.05 to 1% by weight, preferably 0.07 to 0.8% by weight, more preferably 0.1 to 0.7% by weight. When the saturated water absorption ratio of the cyclic olefin polymer of the present invention is within the above range, the optical properties, transparency, phase difference, and phase difference uniformity or dimensional accuracy of the obtained film are as high as humidity and humidity. While maintaining stable conditions, Adhesion to other materials. Since it is excellent in adhesiveness, it is not peeled off during use, and compatibility with additives, such as an antioxidant, is favorable, and the freedom of selection of the kind of additives, and the addition amount of the additives becomes large.

When the saturated water absorption is less than 0.05% by weight, the obtained film has low adhesion or adhesion to other materials, and is likely to be peeled off during use, and the amount of additives such as an antioxidant may be limited. On the other hand, when the saturated water absorption exceeds 1% by weight, changes in optical characteristics or dimensional changes are likely to occur due to water absorption.

Here, the saturated water absorption rate is a value obtained by measuring the weight of the crucible by immersing in water at 23 ° C for one week in accordance with ASTM D570.

The glass transition temperature (Tg) of the cyclic olefin polymer of the present invention is generally 70 to 250 ° C, preferably 90 to 200 ° C, and more preferably 100 to 180 ° C. When Tg is 120 ° C or more, it is preferable because it has excellent heat resistance. When the Tg is less than 90 ° C, the heat distortion temperature is lowered, and there is a problem in heat resistance, and there is a problem that the change in optical characteristics is increased due to the temperature of the obtained film. On the other hand, when the Tg exceeds 200 ° C, the processing temperature at the time of the elongation processing becomes too high, and the copolymer of the present invention may be deteriorated in thermal deterioration, productivity, or workability.

Here, the Tg of the cyclic olefin polymer refers to the maximum differential scanning calorimetry curve obtained by using a differential scanning calorimeter (DSC) at a temperature increase rate of 20 ° C / min and measured under a nitrogen atmosphere. The peak temperature (point A) and the maximum peak temperature -20 °C temperature (point B) are plotted on the differential walk-through heat curve, the tangent line on the baseline starting from point B and starting from point A. The intersection of the tangent is obtained.

Polymerization catalyst

The catalyst used in the production of the cyclic olefin polymer of the present invention, for example, the catalyst described in Olefin Metathesis and Metathesis Polymerization (K.J. IVIN, J.C. MOL, Academic Press 1997) is preferably used. Examples of such a catalyst include (i) (a) at least one selected from the group consisting of compounds of W, Mo, Re, V, and Ti, and (b) an alkali metal element (for example, Li, Na, K). Alkaline earth metal elements (eg, Mg, Ca), Group 12 elements (eg, Zn, Cd, Hg), Group 13 elements (eg, B, Al), Group 14 elements (eg, Si, Sn, Pd), etc. And a metathesis catalyst formed by a combination of at least one selected from the group consisting of at least one of the element-carbon bond or the element-hydrogen bond. In order to increase the activity of the catalyst, it may be added to the (c) additive described later.

Examples of the component (a) of the specific _{embodiment, 6, MoCl 5, ReOCl 3} , VOCl 3, such compounds include WCl TiCl _4, etc. Japanese Laid-Open Patent Publication No. 1-240517 as described in the. These may be used alone or in combination of two or more.

Specific examples of the component (b) include n-C ₄ H ₉ Li, (C ₂ H ₅ ) ₃ Al, (C ₂ H ₅ ) ₂ AlCl, (C ₂ H ₅ ) _1.5 AlCl _1.5 , ( A compound described in JP-A-1-240517, such as C ₂ H ₅ )AlCl ₂ , Methylaluminoxane, or LiH. These may be used alone or in combination of two or more.

As the additive of the above component (c), for example, an alcohol can be suitably used. Further, a compound, an aldehyde, a ketone, an amine or the like can be used. Further, a compound described in JP-A-1-240517 can be used. These may be used alone or in combination of two or more.

The amount of the metathesis catalyst in which the component (a) or the like is combined is the molar ratio of the component (a) and the "(a) component: all monomer" of the all monomer, and is generally 1:500. The range of ~1:500,000, preferably in the range of 1:1,000 to 1:100,000. Further, the ratio of the component (a) to the component (b) is a metal atom (mole) ratio of "(a): (b)", and is generally 1:1 to 1:50, preferably 1:2. The range of 1:30. When the above (c) additive is added to the metathesis catalyst, the ratio of the component (a) to the component (c) is a molar ratio of "(c): (a)", which is generally 0.005:1 to 15:1. Good range of 0.05:1~7:1.

Further, as another catalyst, a metathesis touch formed by (ii) a transition metal-carbene complex or a metal-substituted cyclobutane complex of Groups 4 to 8 of the periodic table can be used. Media.

Specific examples of the catalyst (ii) include W(=N-2,6-C ₆ H ₃ ⁱ Pr ₂ )(=CH ^tert Bu)(O ^tert Bu) ₂ and Mo(=N-2 ,6-C ₆ H ₃ ⁱ Pr ₂ )(=CH ^tert Bu)(O ^tert Bu) ₂ , Ru(=CHCH=CPh ₂ )(PPh ₃ ) ₂ Cl ₂ ,Ru(=CHPh)[P(C ₆ H ₁₁ ) ₃ ] ₂ Cl ₂ and the like. These may be used alone or in combination of two or more.

The amount of the catalyst (ii) used is a molar ratio of "catalyst (ii): all monomer", and is generally in the range of 1:500 to 1:50,000, preferably 1:100 to 1: A range of 10,000.

Further, it is also possible to combine the above-described catalysts (i) and (ii).

The adjustment of the molecular weight of the copolymer used in the present invention can also be carried out by adjusting the polymerization temperature, the type of the catalyst, the kind of the solvent, etc., by allowing the molecular weight regulator to be in the ring-opening copolymerization reaction system. Coexistence is better. As the molecular weight modifier, for example, an α-olefin such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-decene or the like The class and styrene are preferred, and among these, 1-butene and 1-hexene are particularly preferred. These molecular weight modifiers may be used alone or in combination of two or more. The molecular weight modifier is used in an amount of 1 mole per full monomer, typically 0.005 to 0.6 moles, preferably 0.02 to 0.5 moles.

Examples of the solvent used in the ring-opening copolymerization reaction (that is, a solvent for dissolving a monomer, a ring-opening polymerization catalyst, a molecular weight modifier, etc.) include, for example, pentane, hexane, heptane, octane, and hydrazine. Alkane such as alkane or decane; cycloalkane such as cyclohexane, cycloheptane, cyclooctane, decahydronaphthalene or norbornane; aromatics such as benzene, toluene, xylene, ethylbenzene and cumene a compound of a halogenated alkane such as chlorobutane, bromohexane, dichloromethane, dichloroethane, hexamethylene dibromide, chlorobenzene, chloroform or tetrachloroethylene; or a halogenated aryl group; a saturated carboxylic acid ester such as ethyl ester, n-butyl acetate, isobutyl acetate or methyl propionate; an ether such as dibutyl ether, tetrahydrofuran or dimethoxyethane; Hydrocarbons are preferred. These may be used alone or in combination of two or more. The solvent used for the ring-opening polymerization reaction is a "solvent; all monomer" weight ratio, generally in an amount of from 1:1 to 10:1, preferably from 1:1 to 5:1. ideal.

The temperature of the monomer solution when the catalyst is added is preferably from 30 to 200 ° C, more preferably from 50 ° C to 180 ° C. When the temperature is lower than 30 ° C, the yield of the polymer is lowered; when it exceeds 200 ° C, the molecular weight control becomes difficult.

The reaction time at the time of the ring-opening copolymerization reaction is usually 0.1 to 10 hours, preferably 0.1 to 9 hours, more preferably 0.1 to 8 hours.

A ring-opening copolymer in which each of the cyclic olefin monomers is subjected to ring-opening copolymerization only has an olefinic unsaturated bond in the molecule, and the olefinic unsaturated bond is caused by a problem such as heat-resistant coloring. Hydrogenation is preferred. The hydrogenation method, preferably the hydrogenation rate, is as described above.

<additive>

In the cyclic olefin polymer of the present invention, various additives may be blended as needed. For example, it is possible to blend an antioxidant selected from a phenol-based antioxidant, a lactone-based antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant by improving oxidation stability, preventing coloration, and deterioration. The antioxidant may be blended in a ratio of 0.001 to 5 parts by weight per 100 parts by weight of the polymer. Specific examples of the antioxidant include, for example,

1) 2,6-di-t-butyl-4-methylphenol, 4,4'-thiobis-(6-tert-butyl-3-methyl-phenyl), 1,1-bis (4 -hydroxyphenyl)cyclohexane, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), hydrazine [methylene-3-(3,5-di-third) Butyl-4-hydroxyphenyl)propionate]methane, 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid stearate, 2,5-di-third Butylhydroquinone and pentaerythritol-indole [3-(3,5-di-t-butyl-4-hydroxyphenyl)]propionate a phenolic antioxidant or a hydroquinone antioxidant,

2) bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphate, ginseng (2,4-di-t-butylphenyl) phosphate, bismuth (2,4 -di-tert-butyl-5-methylphenyl)4,4'-biphenyldiphosphinate, 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl Base ester, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphate, ginseng (4-methoxy-3,5-diphenyl) phosphate and hexamethylenephenylphosphoric acid Phosphate such as ester is a secondary antioxidant, and

3) A sulfur-based secondary antioxidant such as dilauryl-3,3'-thiodipropionate or 2-mercaptobenzimidazole.

Further, a flame retardant may be blended in the cyclic olefin polymer of the present invention. A known flame retardant can be used, and examples thereof include a halogen-based flame retardant, a fluorene-based flame retardant, a phosphate-based flame retardant, and a metal hydroxide. Among them, a small amount is blended to exhibit an effect, so that the phosphate ester-based flame retardant which deteriorates water absorption, low dielectric property and transparency to a minimum is preferable; and 1,3-bis(phenylphosphonium-based ( Phosphoryl)) benzene, 1,3-bis(diphenylphosphonium)benzene, 1,3-bis[di(alkylphenyl)phosphonium]benzene, 1,3-bis[di(2', 6'-dimethylphenyl)phosphonium]benzene, 1,3-bis[bis(2',6'-diethylphenyl)phosphonium]benzene, 1,3-bis[di(2) ',6'-diisopropylphenyl)phosphonium]benzene, 1,3-bis[bis(2',6'-dibutylphenyl)phosphonium]benzene, 1,3-double [ Di(2'-tert-butylphenyl)phosphoryl]benzene, 1,3-bis[bis(2'-isopropylphenyl)phosphonium]benzene1,3-bis[ (2'-Methylphenyl)phosphonium]benzene, 1,4-bis(diphenylphosphonium)benzene, 1,4-bis[bis(2',6'-dimethylphenyl) Phosphonic acid]benzene, 1,4 - bis[bis(2',6'-diethylphenyl)phosphonium]benzene, 1,4-bis[bis(2',6'-diisopropylphenyl)phosphonium]benzene, 1,4-bis[bis(2'-tert-butylphenyl)phosphonium]benzene, 1,4-bis[bis(2'-isopropylphenyl)phosphonium]benzene, 1,4 - bis[bis(2'-methylphenyl)phosphonium]benzene and 4,4'-bis[bis(2",6"-dimethylphenyl)phosphonium phenyl]dimethylmethane The condensed phosphate ester-based flame retardant is more preferred. The blending amount is determined according to the selected flame retardant and the degree of flame retardancy required, and is preferably 0.5 to 40 parts by weight, and 2 to 30 parts by weight, based on 100 parts by weight of the cyclic olefin polymer. More preferably, it is particularly good in 4 to 20 parts by weight. When the blending amount of the flame retardant is less than 0.5 part by weight, the effect is insufficient. On the other hand, when it is used in excess of 40 parts by weight, the transparency is deteriorated, the electrical properties such as the dielectric property are deteriorated, the water absorption rate is increased, and the heat resistance is deteriorated.

In the cyclic olefin polymer of the present invention, an antioxidant, a heat stabilizer, a light stabilizer, a phase difference adjuster, an ultraviolet absorber, an antistatic agent, a dispersant, a processability enhancer, and chlorine may be further optionally used. Scavenger, flame retardant, crystallization nucleating agent, anti-caking agent, anti-fogging agent, mold release agent, pigment, organic or inorganic filler, neutralizer, slip agent, decomposer, metal deactivator, pollution A known additive such as a material, an antibacterial agent, or another resin or a thermoplastic elastomer is added in a range that does not impair the effects of the invention.

<Manufacture of unprocessed film>

The unprocessed film used for the production of the retardation film of the present invention is obtained by dissolving a cyclic olefin polymer in a suitable solvent by casting and molding. It is obtained for films and sheets. Moreover, it can also be obtained by film formation by a well-known method, such as a melt-extrusion method.

The obtained unprocessed film has an excellent balance of optical properties such as transparency, chemical resistance, heat resistance, water resistance, and moisture resistance.

The unprocessed film has a film thickness of 100 to 250 μm, preferably 120 to 200 μm, and the difference between the maximum thickness and the minimum thickness of the film is 3 μm or less, preferably 2 μm or less.

<Manufacture of retardation film>

In the retardation film of the present invention, the unprocessed film is suitably obtained by lateral uniaxial stretching at the above-described stretching ratio.

In order to obtain the retardation film of the present invention, it is necessary to apply a step of heat extension treatment to the unprocessed film.

The temperature at which the heat extension treatment is carried out is based on the glass transition temperature (Tg) of the unprocessed film formed from the cyclic olefin polymer used in the present invention, and is generally (Tg - 10 ° C) to (Tg + 70 ° C). The range is preferably in the range of (Tg ± 0 ° C) to (Tg + 50 ° C). In the above range, no thermal deterioration of the film occurs, and it is preferable that the film can be stretched without breaking the film. Here, the Tg is obtained by using the above-described differential scanning calorimeter (DSC).

The extension is ideal for lateral uniaxial stretching of the tenter (unidirectional extension in the width direction). By performing the lateral uniaxial stretching, the maximum refractive index in the plane becomes the film width direction, and when it is adhered to the polarizer, the roll to roll can be bonded, and the productivity is improved. Transverse uniaxial extension, temperature distribution For control to be set within a temperature of ±0.5 ° C, preferably within a set temperature of ± 0.3 ° C, and more preferably within an oven controlled to within ± 0.2 ° C of the set temperature, the Re, NZ, and optical axes can be properly controlled. It is ideal for optical properties.

Here, the set temperature of the lateral uniaxial extension may be equal to the temperature in the entire field in the oven, and the temperature of the distribution may be set gradually or decreasingly. When the set temperature is the temperature at which the distribution is set, the actual temperature distribution in the oven and the set temperature distribution are within ±0.5 ° C, preferably within ±0.3 ° C, and more preferably within ± 0.2 ° C.

The extension speed of the transverse uniaxial stretching is, for example, 2 to 100 m/min, preferably 5 to 50 m/min. The stretching ratio and the number of extensions are appropriately selected depending on the desired phase difference. The stretching ratio is 2.5 to 5.5 times, preferably 2.8 to 5.4 times, and particularly preferably 3.0 to 5.3 times.

The number of extensions is 1 to 2 times.

In the present invention, when the stretching ratio is more than 4 times at a high magnification, it is preferable to perform the lateral uniaxial stretching twice to ensure the uniformity of the thickness and the phase difference after the stretching; the thickness and the phase difference are obtained by one extension. The case of uniformity is preferably one of the number of extensions. Further, the stretching magnification in the case where the lateral uniaxial stretching is performed twice is expressed by a value obtained by multiplying the first stretching magnification and the second stretching magnification.

The retardation film of the present invention has a thickness of 20 to 100 μm, preferably 25 to 90 μm. Further, the difference between the maximum thickness and the minimum thickness of the film is within 3 μm.

Above, the selection and copolymerization ratio of the copolymerized monomers (I') and (II') The molecular weight adjustment in the polymerization reaction, the Tg of the copolymer, the film thickness and the stretching ratio are within the above preferred range, so that α (MD) and α (TD) of the retardation film can be controlled to In a preferred range, excessive dimensional change and dimensional anisotropy during heating are prevented, and warpage or bending of the polarizing plate in which the retardation film is laminated on at least one side of the polarizing film can be reduced.

<Use>

The retardation film of the present invention has excellent transparency and heat resistance and has low water absorption, and the polarizing plate which is laminated by the retardation film is less warped or bent, so that the polarizing plate is manufactured and the liquid crystal display is used. The operation of the device is easy to manufacture, and the liquid crystal display element is excellent in uniformity, stability, and high-performance. Therefore, various liquid crystal display elements, which are also suitable for use in a vertical alignment type liquid crystal display element, can be used for good viewing angle compensation.

Hereinafter, specific embodiments of the present invention will be described, but the present invention is not limited to the embodiments. In addition, the following "parts" and "%" mean "parts by weight" and "% by weight" unless otherwise specified.

Further, each evaluation item in the following examples was measured by the following method.

<glass transition temperature (Tg)>

Using a differential scanning calorimeter manufactured by Seiko Instruments DSC), at a heating rate of 20 ° C / min, the maximum peak temperature (point A) of the differential scanning scanning heat curve obtained at the time of measurement under a nitrogen atmosphere and the maximum peak temperature of -20 ° C (point B) On the differential scanning heat curve, the intersection of the tangent on the baseline starting from point B and the tangent starting from point A is obtained.

<saturated water absorption rate>

The sample was immersed in water at 23 ° C for 1 week according to ASTM D570, and the change in weight of the sample before and after immersion was measured, and the saturated water absorption rate was determined from the value.

<Full light transmittance>

The measurement was carried out using a Haze Meter "HGM-2DP type" manufactured by Suga Test Instruments.

<Phase phase difference of transmitted light>

"KOBRA-21ADH" manufactured by Oji Scientific Instruments Co., Ltd. was used to measure the phase difference Re and NZ at a wavelength of 589 nm.

<logarithmic viscosity>

The measurement was carried out using a Ubbelohde type viscometer in chloroform or cyclohexane (sample concentration: 0.5 g/dL) at 30 °C.

<weight average molecular weight and number average molecular weight>

The weight average molecular weight (Mw) and the number average molecular weight (Mn) in terms of polystyrene were measured by gel permeation chromatography (GPC) (HLC-8020, manufactured by TOSOH) using a tetrahydrofuran (THF) solvent. , molecular weight distribution (Mw / Mn)).

<Average linear expansion coefficient>

The "TMA-SS6000" manufactured by Seiko Instruments Co., Ltd. was used to measure the average linear expansion of -40 ° C to 85 ° C in an elongation mode, a load of 1 g, a film width of 4 mm, a chuck interval of 20 mm, and a temperature rise of 10 ° C / min. Coefficients (α(MD) and α(TD)).

<Synthesis Example 1>

8-methyl-8-methoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene (specific monomer) 250 parts, with 1-hexene (molecular weight regulator) 18 parts of 750 parts of toluene (solvent for ring-opening polymerization) were placed in a nitrogen-substituted reaction vessel, and the solution was heated to 60 °C. Next, 0.62 parts of a toluene solution (1.5 mol/liter) of triethylaluminum as a polymerization catalyst, and a third butanol and a tungsten hexachloride modified with methanol were added to the solution in the reaction vessel. Alcohol: methanol: tungsten = 0.35 mol: 0.3 mol: 1 mol) in 3.7 parts of a toluene solution (concentration: 0.05 mol/liter), and the solution was opened by heating at 80 ° C for 3 hours to carry out ring-opening polymerization. Ring polymer solution. The polymerization conversion ratio in this polymerization reaction was 97%.

1,000 parts of the ring-opening polymer solution thus obtained was placed in an autoclave, and 0.12 parts of RuHCl(CO)[P(C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution at a hydrogen pressure of 100 kg/ cm ^2, at a reaction temperature of 165 deg.] C, was heated with stirring for 3 hours the hydrogenation reaction. After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen pressure was released. This reaction solution was poured into a large amount of methanol, and the coagulum was separated and recovered, and after drying, a hydrogenated polymer (hereinafter referred to as "resin A") was obtained.

The hydrogenation ratio measured by ¹ H-NMR of the obtained resin A was 99.9%; the glass transition temperature (Tg) measured by the DSC method was 165 ° C; polystyrene conversion by GPC method The number average molecular weight (Mn) was 32,000, the weight average molecular weight (Mw) was 137,000, the molecular weight distribution (Mw/Mn) was 4.29, the saturated water absorption at 23 ° C was 0.3%, and the logarithmic viscosity in chloroform at 30 ° C was 0.78 dl/g.

<Synthesis Example 2>

Using 8-methyl-8-methoxycarbonyltetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene 215 parts, and bicyclo[2.2.1]hept-2-ene 35 parts A hydrogenated polymer (hereinafter referred to as "resin B") was obtained in the same manner as in Synthesis Example 1 except that the amount of 1-hexene added was changed to 30 parts.

The hydrogenation rate measured by ¹ H-NMR of the obtained resin B was 99.9%; the Tg measured by the DSC method was 125 ° C; the polystyrene equivalent Mn measured by the GPC method was 46,000. The Mw was 190,000 and the Mw/Mn was 4.15, the saturated water absorption at 23 ° C was 0.18%, and the logarithmic viscosity in chloroform at 30 ° C was 0.53 dl / g.

<Synthesis Example 3>

Use four rings [4.4.0.1 ^2,5 .1 ^7,10 ]-3-dodecene 53 parts, and 8-ethylene tetracyclo[4.4.0.1 ^2,5 .1 ^7,10 ]-3-10 46 parts of diene, and 66 parts of tricyclo [4.3.0.1 ^2,5 ]-deca 3,7-diene, the amount of 1-hexene added is 18 parts, as a solvent for ring-opening polymerization, except that cyclohexane is used. The hydrogenated polymer (hereinafter referred to as "resin C") was obtained in the same manner as in Synthesis Example 1 except for the alkane-substituted toluene.

The hydrogenation rate of the obtained resin C was 99.9%, and the Tg measured by the DSC method was 137 ° C; the Mn was 39,000, the Mw was 158,000, and the Mw/Mn was measured by the GPC method (solvent: o-dichlorobenzene). The saturated water absorption at 4.0 ° C was 0.01%, and the logarithmic viscosity in chloroform at 30 ° C was 0.70 dl / g.

<Manufacturing Example 1> Manufacturing of resin film (A-1)

The above resin A was dissolved in toluene to a concentration of 30% (solution viscosity at room temperature was 30,000 mPa·s), as an antioxidant, pentaerythritol ruthenium [3-(3,5-di-t-butyl-4-hydroxyl) Phenyl)propionate] 0.1 parts by weight of the resin was added, and a metal fiber sintered filter having a pore diameter of 5 μm manufactured by Pall Japan was used, and the flow rate of the solution was controlled while the differential pressure was 0.4 MPa. The obtained solution was applied to a substrate having a thickness of 100 μm which was hydrophilized (adhesively adhered) by an acrylic system using "INVEX Lab Coater" manufactured by Inoue Metal Co., Ltd., which was installed in a clean room of class 1000. Film (Dongli) TORAY) "Lumirror U94" was used to make the film thickness after drying to 130 μm, which was once dried at 50 ° C, and then subjected to secondary drying at 90 ° C. The resin film (A-1) was obtained by peeling off the PET film. The total light transmittance of the obtained resin film (A-1) was 93%.

<Manufacturing Example 2> Manufacture of resin film (B-1)

A resin film (B-1) having a thickness of 150 μm was obtained by the same method as in Production Example 1 except that Resin B was used instead of Resin A. The total light transmittance of the obtained resin film (B-1) was 93%.

<Manufacturing Example 3> Manufacture of resin film (C-1)

A resin film (C-1) having a thickness of 150 μm was obtained by the same method as in Production Example 1 except that the resin A was used instead of the resin A and the toluene was replaced with cyclohexane. The total light transmittance of the obtained resin film (C-1) was 93%.

<Manufacturing Example 4> Manufacturing of resin film (B-2)

The resin A was extruded downstream by a gear pump using a twin-axis extruder (TEM-48, manufactured by Toshiba Machine Co., Ltd.), and a metal fiber made of Japanese fine wire having a nominal mesh size of 10 μm was used. Sintering filter for melt filtration; using hanger type T die (650mm Width), a gap of 0.5 mm at the exit of the T die was extruded at 280 ° C to form a film, and a film (B-2) having a thickness of 150 μm was obtained by pressing on a cooling roll. The obtained film (B-2) had a total light transmittance of 93%.

<Manufacturing Example 5> Manufacturing of resin film (C-2)

A resin film (C-2) having a thickness of 150 μm was obtained by the same method as in Production Example 4 except that the resin C was used instead of the resin A. The total light transmittance of the obtained resin film (C-2) was 93%.

[Example 1] Fabrication of retardation film (A-11)

The resin film (A-1) was set at 180 ° C and 2.5 times in a tenter type transverse stretching machine, and a retardation film (A-11) having a film thickness of 51 to 53 μm was obtained by lateral uniaxial stretching. The obtained stretched film had Re of 155 nm and NZ of 1.40. Further, the average linear expansion coefficient (α(TD)) in the extending direction (film width direction) is 60 ppm/° C., and the average linear expansion coefficient (α (MD)) in the direction perpendicular to the extending direction (the longitudinal direction of the film) is 72ppm/°C.

[Embodiment 2] Fabrication of retardation film (B-11)

The resin film (B-1) was stretched by uniaxial stretching at 147 ° C and 3.0 times to obtain a retardation film (B-11) having a film thickness of 47 to 50 μm. . The obtained stretched film had Re of 105 nm and NZ of 1.35. Further, α (TD) was 74 ppm/° C. and α (MD) was 85 ppm/° C.

[Example 3] Fabrication of retardation film (B-21)

A retardation film (B-21) having a film thickness of 48 to 51 μm was obtained by the same method as in Example 2 except that the resin film (B-2) was used instead of the resin film (B-1). Further, the obtained stretched film had Re of 155 nm and NZ of 1.35. α (TD) was 72 ppm/° C. and α (MD) was 86 ppm/° C.

[Example 4] Fabrication of retardation film (B-22)

The resin film (B-2) was set at 133 ° C and 2.0 times, and uniaxially stretched in the transverse direction. Further, the film was set at 147 ° C and 2.4 times by transverse uniaxial stretching to obtain a net 4.8-fold extension and film thickness. Phase difference film (B-22) of 30~33 μm. The obtained stretched film had a Re of 150 nm and a NZ of 1.20. Further, α (TD) was 74 ppm/° C. and α (MD) was 87 ppm/° C.

[Example 5] Fabrication of retardation film (C-11)

The resin film (C-1) was stretched at 157 ° C and 3.0 times to obtain a stretched film (C-11) having a film thickness of 49 to 52 μm. Income The Re of the stretched film was 160 nm and the NZ was 1.33. Further, α (TD) was 63 ppm/° C. and α (MD) was 70 ppm/° C.

[Embodiment 6] Fabrication of retardation film (C-21)

A resin film (C-2) was used instead of the resin film (C-1), and a retardation film (C-21) having a film thickness of 48 to 51 μm was obtained by lateral stretching at 160 ° C and 3.0 times. The obtained stretched film had Re of 142 nm and NZ of 1.34. Further, α (TD) was 68 ppm/° C. and α (MD) was 74 ppm/° C.

[Comparative Example 1] Stretch film (A-12)

The resin film (A-1) was longitudinally stretched at 185 ° C by 2.7 times to obtain a stretched film (A-12) having a film thickness of 75 to 77 μm. The obtained stretched film had Re of 400 nm and NZ of 1.03. Further, α (TD) was 92 ppm/° C. and α (MD) was 58 ppm/° C.

<Manufacturing Example 6> Manufacture of polarizing film

Polyvinyl alcohol (hereinafter referred to as "PVA") was placed in a dyeing bath (temperature: 30 ° C) made of an aqueous solution having an iodine concentration of 0.03% and a potassium iodide concentration of 0.5%, and was stretched at a stretching ratio of 3 times. Processing; thereafter, placed in an aqueous solution having a boric acid concentration of 5% and a potassium iodide concentration of 8% In the cross-linking bath (temperature: 55 ° C), the post-stretching process was carried out at a stretching ratio of 2 times, and a polarizing film (hereinafter referred to as "polarizer") was obtained by a drying treatment.

<Modulation example> Water system adhesive modulation

A 4% aqueous solution of a PVA-based resin (trade name: 163-03045 (molecular weight: 500, saponification degree: about 88 mol%) and Wako Pure Chemical Industries, Ltd.) was adjusted. On the one hand, a polyurethane-based adhesive (trade name: WLS-201 (non-volatiles 35%), manufactured by Dainippon Ink Chemical Industry Co., Ltd.) is blended with a polyepoxy hardener ( Trade name: 5 parts of CR-5L (100% of active ingredients) and Dainippon Ink Chemical Industry Co., Ltd.). The obtained PVA aqueous solution and the polyurethane resin were mixed at a solid weight ratio of 20:80, and then diluted with water to prepare a mixed aqueous solution (water-based adhesive) of 15%.

[Embodiment 7] Production of polarizing plate (A-111)

On one side of the A4 size retardation film (A-11), corona treatment is performed at an output power of 60 W/m ² /min, and the corona-treated surface and the polarizer are perpendicularly intersected with each other in the direction in which they extend. The water-based adhesive was applied, and the direction in which the polarizers were extended to the mold was fixed at 50 ° C for 3 minutes, followed by drying at 80 ° C for 20 minutes. Then, on the other side of the polarizer, a cellulose triacetate (TAC) film was attached with a PVA-based adhesive, and dried in the same manner to obtain a polarizing plate (A-111).

The obtained polarizing plate had a transmittance of 43.7% and a degree of polarization of 99.9%. When the polarizing plate is removed from the flat plate and the polarizing plate is allowed to stand on a flat surface, the floating of the end portion of the film is about 7 mm.

[Embodiment 8] Production of polarizing plate (B-111)

A polarizing plate (B-111) was obtained in the same manner as in Example 7 except that the stretched film (B-11) was used instead of the stretched film (A-11).

The obtained polarizing plate had a transmittance of 43.5% and a degree of polarization of 99.9%. When the polarizer is placed on a flat surface, the floating of the end of the film is about 8 mm.

[Embodiment 9] Production of polarizing plate (B-211)

A polarizing plate (B-211) was obtained by the same method as in Example 7 except that the stretched film (B-21) was used instead of the stretched film (A-11).

The obtained polarizing plate had a transmittance of 43.6% and a degree of polarization of 99.9%. When the polarizer is placed on a flat surface, the floating of the end of the film is about 10 mm.

[Embodiment 10] Production of polarizing plate (B-221)

A polarizing plate (B-221) was obtained by the same method as that of the polarizing plate (A-111) except that the stretched film (B-22) was used instead of the stretched film (A-11).

The obtained polarizing plate had a transmittance of 43.6% and a degree of polarization of 99.9%. When the polarizer is placed on a flat surface, the floating of the end of the film is about 15 mm.

[Example 11] Production of polarizing plate (C-111)

A polarizing plate (C-111) was obtained by the same method as in Example 7 except that the stretched film (C-11) was used instead of the stretched film (A-11).

The obtained polarizing plate had a transmittance of 43.4% and a degree of polarization of 99.9%. When the polarizing plate is removed from the flat surface, the floating end of the film is about 7 mm.

[Embodiment 12] Production of polarizing plate (C-211)

A polarizing plate (C-211) was obtained in the same manner as in Example 7 except that the stretched film (C-21) was used instead of the stretched film (A-11).

The obtained polarizing plate had a transmittance of 43.6% and a degree of polarization of 99.9%. When the polarizing plate is placed on a flat surface, the end of the film is removed. The float is about 7 mm.

[Comparative Example 2] Production of polarizing plate (A-121)

A polarizing plate (A-121) was obtained in the same manner as in Example 7 except that the stretched film (A-12) was used instead of the stretched film (A-11).

The obtained polarizing plate had a transmittance of 43.7% and a degree of polarization of 99.9%. When the self-shaped box is removed and the polarizing plate is left on the flat surface, the film curls into a cylindrical shape.

[Industrial availability]

The retardation film of the present invention has excellent uniformity and stability, and has less warpage after bonding with a polarizing film or the like, and is suitable for use in the production of a polarizing plate, and is suitable for use in a mobile phone, a notebook computer, or a car. Various liquid crystal display devices such as navigation, portable game consoles, LCD TVs, and liquid crystal monitors for large displays are used.

Claims (5)

A retardation film which is formed of a cyclic olefin polymer and which is characterized by satisfying the following formulas (1) to (5), (1) 70 nm ≦ Re ≦ 300 nm (2) 1.1 ≦ NZ ≦ 1.7 (formula) In (1) to (2), Re is the in-plane phase difference of the film at a wavelength of 589 nm, expressed by Re = (nx - ny) × d, and NZ is NZ = (nx - nz) / (nx - ny) The coefficient of representation; wherein nx is the maximum refractive index in the plane of the film, ny is the refractive index perpendicular to the direction of nx in the plane of the film, and nz is the refractive index in the film thickness direction perpendicular to nx and ny. , d indicates the thickness (nm) of the film, (3) 30 ppm / ° C ≦ α (MD) ≦ 90 ppm / ° C (4) 30 ppm / ° C ≦ α (TD) ≦ 90 ppm / ° C (5) | α (MD) - α(TD)|≦25ppm/°C (in equations (3) to (5), α(MD) represents the average linear expansion coefficient in the longitudinal direction of the film, and α(TD) represents the average linear expansion coefficient in the film width direction. However, the average linear expansion coefficient is any value between -40 ° C and 85 ° C). The retardation film of claim 1, wherein the cyclic olefin polymer is a structural unit represented by the following formula (I). [In the formula (I), m is an integer of 1 or more; p is an integer of 0 or more; D is a group represented by -CH=CH- or -CH ₂ CH ₂ -; and R ¹ to R ⁴ are each independently The ground includes a hydrogen atom, a halogen atom, a bond group containing an oxygen atom, a sulfur atom, a nitrogen atom or a halogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, and an alkyl group selected from a hydroxyl group and a carbon number of 1 to 10. Oxyl, carbonyloxy, alkoxycarbonyl, aryloxycarbonyl, cyano, decylamino, quinone imine, triorganosalkoxy, triorganosilalkyl, amine, decyl, alkoxyalkyl An atom or a group of a group of a sulfonyl group and a carboxyl group; R ¹ and R ² may be bonded to each other to form a phenyl group, and R ³ and R ⁴ may be bonded to each other to form a phenyl group]. For example, in the phase difference film of claim 1, wherein the film thickness is 20 to 100 μm, the difference between the maximum thickness and the minimum thickness of the film is 3 μm or less. A method for producing a phase difference film characterized in that a film thickness is 100 to 250 μm, and a raw film film of a cyclic olefin polymer having a difference between a maximum thickness and a minimum thickness of the film of 3 μm is used as a stretching ratio. A laterally uniaxially stretched in a manner of 2.5 to 5.5 times, and a retardation film according to any one of the first to third aspects of the patent application is obtained. A polarizing plate characterized by at least one side of a polarizing film, a layer A phase difference film according to any one of claims 1 to 3 is applied.