JP2009020485A - Polarizing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate having an excellent polarizing function, excelling in characteristics such as optical characteristics, heat resistance and chemical resistance, hardly causing separation or deformation even in long-term use and having excellent durability and high reliability. <P>SOLUTION: The polarizing plate is formed by laminating a norbornene-based resin film (a) and a norbornene-based resin film (b) on both faces of a polarizing film, and laminating an adhesive layer on a face opposite to the polarizing film, wherein the adhesive layer contains a polymer having structural units derived from specific alkyl(meth)acrylate and having polystyrene conversion weight average molecular weight of 1,500,000 or more by gel permeation chromatography. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polarizing plate. More specifically, the present invention relates to a polarizing plate in which a norbornene resin film, a polarizing film, an adhesive layer and, if necessary, a hard coat layer are laminated.

  A polarizing plate (polarizing film) used for a liquid crystal display or the like is usually formed from a substrate (optical film) excellent in transparency and a polarizing film (polarizer). Moreover, the said polarizing plate may be formed from the film (retardation film) which has the function to provide retardation to transmitted light obtained by extending | stretching an optical film, and a polarizing film.

  Conventionally, polycarbonate films, polyester films, acetate films, and the like have been used as optical films used as polarizing plate substrates or retardation films. However, a polarizing plate using a polycarbonate film or a polyester film has a large photoelastic coefficient, which may change the phase difference imparted to transmitted light due to a slight change in stress, and the acetate film has low heat resistance. Since the water absorption is high, there is a problem that the polarizing plate using the same is easily deformed depending on the use environment.

  On the other hand, norbornene-based resins are attracting attention as materials for various optical components because they are excellent in transparency, heat resistance, chemical resistance, and the like. Patent Document 1 proposes a polarizing film in which a norbornene resin sheet is laminated as a protective layer on a polarizing film.

Moreover, the adhesion layer used in order to bond a polarizing film and adherends, such as a glass plate, has an acrylic adhesive normally. However, when a general-purpose acrylic adhesive is used, especially when it is stored for a long time under high temperature and high humidity, it becomes inferior in adhesiveness with norbornene resin, or foaming or peeling phenomenon occurs in the adhesive layer. As a result, a polarizing plate fixing structure with sufficient quality could not be obtained.
JP-A-6-511117

  The present invention is intended to solve the problems associated with the prior art as described above, has a good polarization function, is excellent in characteristics such as optical characteristics, heat resistance, chemical resistance, etc., and is used for a long time. Is intended to provide a polarizing plate that is less prone to peeling and deformation, has excellent durability, and high reliability.

In the polarizing plate of the present invention, a norbornene-based resin film (a) and a norbornene-based resin film (b) are laminated on both sides of the polarizing film, respectively, and the surface of the norbornene-based resin film (b) opposite to the polarizing film is Having a structural unit derived from at least one alkyl (meth) acrylate represented by formula (i) and having a polystyrene-reduced weight average molecular weight of 1,500 by gel permeation chromatography (hereinafter also referred to as “GPC”); A pressure-sensitive adhesive layer containing a polymer of 000 or more is laminated.
CH ₂ = CRCOOR '(i)
(In formula (i), R represents a hydrogen atom or a methyl group, and R ′ represents an alkyl group having 1 to 12 carbon atoms.)
The norbornene-based resin film is preferably a film made of a resin obtained by (co) polymerizing a monomer containing at least one compound represented by the following formula (1).

(In the formula (1), R ^{1 to} R ⁴ each independently represent a hydrogen atom, a halogen atom, or a monovalent group that may contain oxygen, nitrogen, sulfur or silicon. R ¹ and R ² Or R ³ and R ⁴ may be bonded to each other to form an alkylidene group, or R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ may be bonded to each other. And may form a monocyclic or polycyclic carbocyclic or heterocyclic ring, where x is 0 or an integer of 1 to 3, and y is 0 or 1.)

It is preferable that a hard coat layer is laminated directly or via another layer on the surface of the norbornene resin film (a) opposite to the polarizing film.
Moreover, it is preferable that at least one norbornene-based resin film is a retardation film.
Furthermore, it is preferable that at least one norbornene-based resin film contains a benzotriazole-based ultraviolet absorber.

  According to the present invention, it has a good polarization function, excellent properties such as optical properties, heat resistance, chemical resistance, and the like, and hardly peels and deforms even in long-term use, has excellent durability, and high reliability. Can be obtained.

Hereinafter, the present invention will be specifically described.
In the polarizing plate of the present invention, a norbornene-based resin film (a) and a norbornene-based resin film (b) are respectively laminated on both sides of a polarizing film, and a specific weight is formed on the surface of the norbornene-based resin film (b) opposite to the polarizing film. It is characterized in that an adhesive layer containing a coalescence is laminated. It is preferable that a hard coat layer is laminated directly or via another layer on the surface of the norbornene-based resin film (a) opposite to the polarizing film. That is, the layer structure of the polarizing film of the present invention is (hard coat layer) / norbornene resin film (a) / polarizing film / norbornene resin film (b) / adhesive layer. In addition, you may have another layer between said each layer.

<Norbornene resin film>
The norbornene resin constituting the norbornene resin films (a) and (b) used in the present invention is a resin obtained by (co) polymerizing a monomer composition containing at least one norbornene compound, or A resin obtained by hydrogenating this resin as required.

(Monomer composition)
As a norbornene-type compound contained in the said monomer composition, the norbornene-type compound represented by the said Formula (1) can be mentioned, for example.

In formula (1), R ^{1 to} R ⁴ each independently represent a hydrogen atom; a halogen atom; or a monovalent group that may contain oxygen, nitrogen, sulfur or silicon. Examples of the monovalent group include a monovalent organic group, a cyano group, and an amino group. Furthermore, examples of the monovalent organic group include substituted or unsubstituted hydrocarbon groups having 1 to 15 carbon atoms, which may have a linking group containing oxygen, nitrogen, sulfur or silicon. x represents 0 or an integer of 1 to 3, and y represents 0 or 1.

R ¹ and R ² or R ³ and R ⁴ may be bonded to each other to form an alkylidene group, or R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ may be bonded to each other to form a monocyclic or polycyclic carbocyclic ring or a monocyclic or polycyclic heterocyclic ring. Here, “R ¹ and R ² are bonded to each other to form an alkylidene group” means that either R ¹ or R ² is eliminated and the remaining group is bonded to the ring structure by a double bond. This means a state (the following formula (1 ′)). The same applies to R ³ and R ⁴ . Examples of the carbocyclic or heterocyclic ring include alicyclic and aromatic rings.

The norbornene compounds represented by the above formula (1) may be used singly or in combination of two or more.
Examples of the norbornene-based compound represented by the above formula (1) include the following compounds, but are not limited to these compounds.
Bicyclo [2.2.1] hept-2-ene (norbornene)
5-methyl-bicyclo [2.2.1] hept-2-ene 5-ethyl-bicyclo [2.2.1] hept-2-ene 5-cyclohexyl-bicyclo [2.2.1] hept-2- En-phenyl-bicyclo [2.2.1] hept-2-ene 5- (4-biphenyl) -bicyclo [2.2.1] hept-2-ene 5-methoxycarbonyl-bicyclo [2.2. 1] Hept-2-ene 5-phenoxycarbonyl-bicyclo [2.2.1] hept-2-ene 5-phenoxyethylcarbonyl-bicyclo [2.2.1] hept-2-ene 5-phenylcarbonyloxy- Bicyclo [2.2.1] hept-2-ene 5-methyl-5-methoxycarbonyl-bicyclo [2.2.1] hept-2-ene 5-methyl-5-phenoxycarbonyl-bicyclo [2.2. ] Hept-2-ene 5-methyl-5-phenoxyethylcarbonyl-bicyclo [2.2.1] hept-2-ene 5-vinyl-bicyclo [2.2.1] hept-2-ene 5-ethylidene- Bicyclo [2.2.1] hept-2-ene 5,5-dimethyl-bicyclo [2.2.1] hept-2-ene 5,6-dimethyl-bicyclo [2.2.1] hept-2- En5-fluoro-bicyclo [2.2.1] hept-2-ene 5-chloro-bicyclo [2.2.1] hept-2-ene 5-bromo-bicyclo [2.2.1] hept-2 -Ene 5,6-difluoro-bicyclo [2.2.1] hept-2-ene 5,6-dichloro-bicyclo [2.2.1] hept-2-ene 5,6-dibromo-bicyclo [2. 2.1] Hept-2-ene 5-hydroxy-bicyclo [ 2.1] hept-2-ene 5-hydroxyethyl-bicyclo [2.2.1] hept-2-ene 5-cyano-bicyclo [2.2.1] hept-2-ene 5-amino-bicyclo [2.2.1] Hept- ² -entylcyclo [4.3.0.1 ^2,5 ] dec-3-entylcyclo [4.4.0.1 ^2,5 ] undec-3-ene 7- Methyl-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-ethyl-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-cyclohexyl-tricyclo [4. 3.0.1 ^2,5 ] dec-3-ene 7-phenyl-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7- (4-biphenyl) -tricyclo [4.3. 0.1 ^2,5] dec-3-ene 7,8-dimethyl - tricyclo [4.3.0.1 ^2,5] dec-3-ene 7,8,9- Rimechiru - tricyclo [4.3.0.1 ^{2, 5]} dec-3-ene 8-methyl - tricyclo [4.4.0.1 ^{2, 5]} undec-3-en 8-phenyl - tricyclo [4. 4.0.1 ^2,5 ] undec-3-ene 7-fluoro-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-chloro-tricyclo [4.3.0.1 ^{2 , 5} ] dec-3-ene 7-bromo-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7,8-dichloro-tricyclo [4.3.0.1 ^2,5 ] deca -3-ene 7,8,9-trichloro-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-chloromethyl-tricyclo [4.3.0.1 ^2,5 ] deca- 3-ene 7-dichloromethyl-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-trichloromethyl-tricyclo [4.3.0.1 ^2,5 Deca-3-ene 7-hydroxy-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-cyano-tricyclo [4.3.0.1 ^2,5 ] dec-3-ene 7-amino-tricyclo [4.3.0.1 ^2,5 ] dec-3-enetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-enepentacyclo [7.4.0.1 ^2,5 . 1 ^8,11 . 0 ^7,12] pentadeca-3-ene hexamethylene cyclo [8.4.0.1 ^2,5. 1 ^7,14 . 1 ^9,12 . 0 ^8,13] heptadec-3-en 8-methyl - tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene 8-ethyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-cyclohexyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-phenyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8- (4-biphenyl) -tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-methoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-phenoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-phenoxyethylcarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-phenylcarbonyloxy-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-methyl-8-methoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-methyl-8-phenoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-methyl-8-phenoxyethylcarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-vinyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-ethylidene-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8,8-dimethyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8,9-dimethyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-fluoro-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-chloro-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-bromo-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8,8-dichloro-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8,9-dichloro-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8,8,9,9-tetrachloro-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-hydroxy-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-hydroxyethyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-methyl-8-hydroxyethyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-cyano-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene 8-amino-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene The kind and amount of the norbornene-based compound used in the present invention are appropriately selected according to the required properties of the resin.

Among the norbornene compounds represented by the above formula (1), a structure containing at least one atom selected from an oxygen atom, a nitrogen atom, a sulfur atom and a silicon atom (hereinafter referred to as “polar structure”). Is preferable in that it has excellent adhesion and adhesion to other materials. In particular, in the above formula (1), R ¹ and R ³ are a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, preferably a hydrogen atom or a methyl group, and any one of R ² or R ⁴ is a polar structure. A compound having a hydrogen atom and the other being a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms is preferable in that the water absorption (wet) property of the obtained resin is lowered. Furthermore, a norbornene-based compound in which a group having a polar structure is a group represented by the following formula (2) has a good balance between the heat resistance and water absorption (humidity) of the resulting resin and is preferably used.

− (CH ₂ ) _z COOR ”(2)
(In formula (2), R ″ represents a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms, and z represents 0 or an integer of 1 to 10).

  In the above formula (2), the smaller the value of z, the higher the glass transition temperature of the resulting polymer hydrogenated product and the better the heat resistance, so z is preferably an integer of 0 or 1 to 3, Furthermore, a monomer in which z is 0 is preferable because it can be easily synthesized. In addition, R ″ in the above formula (2) tends to decrease the water absorption (wet) property of the hydrogenated polymer obtained as the number of carbon atoms increases, but also tends to decrease the glass transition temperature. From the viewpoint of maintaining heat resistance, a hydrocarbon group having 1 to 10 carbon atoms is preferable, and a hydrocarbon group having 1 to 6 carbon atoms is particularly preferable.

  In the above formula (1), a compound in which an alkyl group having 1 to 3 carbon atoms, particularly a methyl group, is bonded to the carbon atom to which the group represented by the above formula (2) is bonded has heat resistance and water absorption (humidity). From the viewpoint of balance of sex. Further, in the above formula (1), a compound in which x is 0 or 1, and y is 0 has high reactivity, a polymer can be obtained in a high yield, and polymer hydrogenation with high heat resistance It can be suitably used because it can be obtained and can be easily obtained industrially.

  In obtaining the norbornene-based resin used in the present invention, a monomer that can be copolymerized with the norbornene-based compound can be included in the monomer composition and polymerized as long as the effects of the present invention are not impaired.

  Examples of these copolymerizable monomers include cycloolefins such as cyclobutene, cyclopentene, cycloheptene, cyclooctene, and cyclododecene; and non-conjugated cyclic polyenes such as 1,4-cyclooctadiene, dicyclopentadiene, and cyclododecatriene. Can be mentioned.

These copolymerizable monomers may be used alone or in combination of two or more.
(Polymerization method)
The polymerization method of the norbornene-based resin used in the present invention is not particularly limited as long as the monomer composition containing the norbornene-based compound can be polymerized. For example, ring-opening polymerization or addition polymerization Can be polymerized.

(1) Ring-opening polymerization Production of a polymer by ring-opening polymerization can be performed by a known ring-opening polymerization reaction for a norbornene-based compound, and a monomer composition containing the norbornene-based compound is polymerized as a polymerization catalyst and polymerized. It can be produced by ring-opening polymerization using a reaction solvent and, if necessary, a molecular weight regulator.

(A) Polymerization catalyst In the present invention, when the monomer composition is polymerized by a ring-opening (co) polymerization reaction, it is preferably performed in the presence of a metathesis catalyst.

This metathesis catalyst is
(A) at least one compound selected from compounds having W, Mo and Re (hereinafter referred to as compound (A));
(B) Deming periodic table group IA elements (for example, Li, Na, K, etc.), group IIA elements (for example, Mg, Ca, etc.), group IIB elements (for example, Zn, Cd, Hg, etc.), group IIIA elements (For example, B, Al, etc.), a compound having a group IVA element (for example, Si, Sn, Pb, etc.), or a group IVB element (for example, Ti, Zr, etc.), The catalyst comprises a combination of at least one compound selected from compounds having at least one bond between this element and hydrogen (hereinafter referred to as compound (B)). In order to enhance the activity of the catalyst, an additive (C) described later may be further added.

Examples of the compound (A) include W, Mo or Re halides, oxyhalides, alkoxyhalides, alkoxides, carboxylates, (oxy) acetylacetonates, carbonyl complexes, acetonitrile complexes, hydride complexes, and derivatives thereof. Alternatively, combinations thereof may be mentioned, and W and Mo compounds are preferable from the viewpoint of polymerization activity and practicality, and halides, oxyhalides and alkoxyhalides thereof are particularly preferable. Moreover, you may use the mixture of 2 or more types of compounds which produce | generate the said compound by reaction. Further, these compounds may be complexed with an appropriate complexing agent such as P (C ₆ H ₅ ) ₅ , C ₅ H ₅ N, and the like.

As the compound (A), WCl ₆ , WCl ₅ , WCl ₄ , WBr ₆ , WF ₆ , WI ₆ , MoCl ₅ , MoCl ₄ , MoCl ₃ , ReCl ₃ , WOCl ₄ , MoOCl ₃ , ReOCl ₃ , ReOBr ₃ , W (OC ₆ H ₅ ) ₆ , WCl ₂ (OC ₆ H ₅ ) ₄ , Mo (OC ₂ H ₅ ) ₂ Cl ₃ , Mo (OC ₂ H ₅ ) ₅ , MoO ₂ (acac) ₂ , W (OCOR) ₅ , W (OC ₂ H ₅ ) ₂ Cl ₃ , W (CO) ₆ , Mo (CO) ₆ , Re ₂ (CO) ₁₀ , ReOBr ₃ · P (C ₆ H ₅ ) ₃ , WCl ₅ · P (C ₆ H ₅ ) ₃ , WCl ₆ · C ₅ H ₅ N, W (CO) ₅ · P (C ₆ H ₅ ) ₃ , W (CO) ₃ · (CH ₃ CN) _{3 and the} like. Of these compounds, MoCl ₅ , Mo (OC ₂ H ₅ ) ₂ Cl ₃ , WCl ₆ , W (OC ₂ H ₅ ) ₂ Cl _{3 and the} like are particularly preferred.

As compound _{(B), n-C 4 H 5 Li} , n-C 5 H 11 Na, C 5 H 5 Na, CH 3 MgI, C 2 H 5 MgBr, CH 3 MgBr, n-C 3 H 7 MgCl _{, (C 6 H 5) 3} Al, t-C 4 H 9 MgCl, CH 2 = CHCH 2 MgCl, (C 2 H 5) 2 Zn, (C 2 H 5) 2 Cd, CaZn (C 2 H 5) ₄ , (CH ₃ ) ₃ B, (C ₂ H ₅ ) ₃ B, (n-C ₄ H ₉ ) ₃ B, (CH ₃ ) ₃ Al, (CH ₃ ) ₂ AlCl, (CH ₃ ) ₃ Al ₂ Cl ₃ , CH ₃ AlCl ₂ , (C ₂ H ₅ ) ₃ Al, LiAl (C ₂ H ₅ ) ₂ , (C ₂ H ₅ ) ₃ Al—O (C ₂ H ₅ ) ₂ , (C ₂ H ₅ ) ₂ AlCl, C ₂ H ₅ AlCl ₂ , (C ₂ H ₅ ) ₂ AlH, (iso-C ₄ H ₉ ) ₂ AlH, (C ₂ H ₅ ) ₂ AlOC ₂ H ₅ , (iso-C ₄ H ₉ ) ₃ Al, (C ₂ H ₅ ) ₃ Al ₂ Cl ₃ , (CH ₃ ) ₄ Ga, (CH ₃ ) ₄ Sn, (n—C ₄ H ₉ ) ₄ Sn, (C ₂ H ₅ ) ₃ SiH, (n—C ₆ H ₁₃ ) ₃ Al, (N-C ₄ H ₁₇ ) ₃ Al, LiH, NaH, B ₂ H ₆ , NaBH ₄ , AlH ₃ , LiAlH ₄ , BiH _4, TiH _{4 and the} like can be mentioned. Moreover, the mixture of 2 or more types of compounds which produce | generate these compounds by reaction can also be used. Of these compounds, (CH ₃ ) ₃ Al, (CH ₃ ) ₂ AlCl, (CH ₃ ) ₃ Al ₂ Cl ₃ , CH ₃ AlCl ₂ , (C ₂ H ₅ ) ₃ Al, (C ₂ H ₅ ) ₂ AlCl, (C ₂ H ₅ ) _1.5 AlCl _1.5 , C ₂ H ₅ AlCl ₂ , (C ₂ H ₅ ) ₂ AlH, (C ₂ H ₅ ) ₂ AlOC ₂ H ₅ , (C ₂ H ₅ ) ₂ AlCN, (C ₃ H ₇ ) ₃ Al, (iso-C ₄ H ₉ ) ₃ Al, (iso-C ₄ H ₉ ) ₂ AlH, (C ₆ H ₁₃ ) ₃ Al, (C ₈ H ₁₇ ) ₃ Al, ( C ₆ H ₅ ) ₅ Al and the like are preferable.

As the additive (C) that can be used together with the compound (A) and the compound (B), alcohols, aldehydes, ketones, amines and the like can be suitably used. For example, the following (1) to (1) to (9) can be exemplified.
(1) Boron such as simple boron, BF ₃ , BCl ₃ , B (On-C ₄ H ₉ ) ₃ , (C ₂ H ₅ O ₃ ) ₂ , BF, B ₂ O ₃ , H ₃ BO ₃ Non-organometallic compounds, non-organometallic compounds of silicon such as Si (OC ₂ H ₅ ) ₄ ;
(2) alcohols, hydroperoxides and peroxides;
(3) water;
(4) oxygen;
(5) Carbonyl compounds such as aldehydes and ketones and polymers thereof;
(6) cyclic ethers such as ethylene oxide, epichlorohydrin, oxetane;
(7) Amides such as N, N-diethylformamide and N, N-dimethylacetamide, amines such as aniline, morpholine and piperidine, and azo compounds such as azobenzene;
(8) N-nitroso compounds such as N-nitrosodimethylamine and N-nitrosodiphenylamine;
(9) Compounds containing S—Cl or N—Cl groups such as trichloromelamine, N-chlorosuccinimide, phenylsulfenyl chloride and the like.

  The amount of the metathesis catalyst used is such that the molar ratio of the compound (A) to the total monomers to be subjected to polymerization (compound (A): total monomers) is usually from 1: 500 to 1: 50,000, preferably Is preferably in an amount of 1: 1,000 to 1: 10,000.

The ratio of the compound (A) to the compound (B) (compound (A): compound (B)) is 1: 1 to 1:50, preferably 1: 2 to 1:30 in terms of metal atom ratio.
The ratio of the compound (A) to the compound (C) (compound (C): compound (A)) is 0.005: 1 to 15: 1, preferably 0.05: 1 to 7: 1 in molar ratio. desirable.

(B) Polymerization solvent As the solvent used in the ring-opening polymerization reaction, the monomer composition or catalyst to be used for the polymerization is dissolved and the catalyst is not deactivated. Although it will not specifically limit if a compound melt | dissolves, For example, alkanes, such as pentane, hexane, heptane, octane, nonane, decane; Cycloalkanes, such as cyclohexane, cycloheptane, cyclooctane, decalin, norbornane; benzene, Aromatic hydrocarbons such as toluene, xylene, ethylbenzene, cumene; halogenated alkanes such as chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylene dibromide, chloroform, tetrachloroethylene; halogenated aryl compounds such as chlorobenzene; ethyl acetate, acetic acid n-butyl And saturated carboxylic acid esters such as iso-butyl acetate, methyl propionate, and dimethoxyethane; and ethers such as dibutyl ether, tetrahydrofuran, and dimethoxyethane. These can be used alone or in admixture of two or more. Such a solvent can be used not only as a solvent for dissolving the norbornene-based compound, copolymerizable monomer and / or metathesis catalyst, but also as a solvent constituting a molecular weight regulator solution.

The amount of the solvent used is such that the weight ratio of the solvent to the monomer composition used for polymerization (solvent: monomer composition) is usually 1: 1 to 10: 1, preferably 1: 1 to 5: 1. Is desirable.
(C) Molecular weight regulator The molecular weight of the resulting ring-opening polymer can be controlled by the polymerization temperature, the type of catalyst, and the type of solvent, but it can also be adjusted by allowing a molecular weight regulator to coexist in the reaction system. be able to.

  Suitable molecular weight regulators include, for example, α-olefins such as ethylene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene; and styrene, Aromatic vinyl compounds such as 4-methylstyrene, 2-methylstyrene and 4-ethylstyrene can be exemplified, and among these, 1-butene and 1-hexene are particularly preferable. These molecular weight regulators can be used alone or in admixture of two or more.

The usage-amount of a molecular weight modifier is 0.005-0.6 mol normally with respect to 1 mol of monomers with which a ring-opening polymerization reaction is provided, Preferably it is 0.01-0.5 mol.
(D) Other polymerization conditions The ring-opening polymer can be obtained by ring-opening polymerization of the norbornene compound or ring-opening copolymerization of the norbornene compound and a copolymerizable monomer. Conjugated diene compounds such as polybutadiene, polyisoprene, styrene-butadiene copolymers, ethylene-nonconjugated diene copolymers, polynorbornene, etc., unsaturated hydrocarbons containing two or more carbon-carbon double bonds in the main chain A monomer composition containing a norbornene compound may be subjected to ring-opening polymerization in the presence of a polymer.

(2) Addition polymerization The production of a polymer by addition (co) polymerization can be performed by a known addition polymerization reaction for a norbornene compound, and a monomer composition containing the norbornene compound is used as a polymerization catalyst. Depending on the case, it can be produced by addition polymerization using a solvent for polymerization reaction and, if necessary, a molecular weight regulator.

(A) Polymerization catalyst Examples of the polymerization catalyst used for the addition polymerization include single catalysts such as palladium, nickel, cobalt, titanium, and zirconium, and multi-component systems described in (a-1) to (a-3) below. Although a catalyst is mentioned, the polymerization catalyst used for this invention is not limited to these.

(A-1) Single catalyst system [Pd (CH ₃ CN) ₄ ] [BF ₄ ] ₂ ,
[Pd (PhCN) ₄ ] [SbF ₆ ],
[(Η ³ -crotyl) Pd (cycloocta-1,5-diene)] [PF ₆ ],
[(Η ³ -crotyl) Ni (cycloocta-1,5-diene)] [B (3,5- (CF ₃ ) ₂ C ₆ F ₃ ) ₄ ],
[(Η ³ -crotyl) Ni (cycloocta-1,5-diene)] [PF ₆ ],
[(Η ³ -allyl) Ni (cycloocta-1,5-diene)] [B (C ₆ F ₅ ) ₄ ],
[(Η ³ -crotyl) Ni (cycloocta-1,5-diene)] [SbF ₆ ],
Toluene / Ni (C ₆ F ₅ ) ₂ ,
Benzene / Ni (C ₆ F ₅ ) ₂ ,
Mesitylene / Ni (C ₆ F ₅ ) ₂ ,
Ethyl ether / Ni (C ₆ F ₅ ) ₂ ,
Transition metal compounds such as

(A-2) Multi-component catalyst system (1)
A combination of a palladium complex having an α or α, π bond and an organoaluminum or a super strong acid salt can be mentioned. In particular,
Di-μ-chloro-bis (6-methoxybicyclo [2.2.1] hept-2-ene-endo-5σ, 2π) Pd, methylalumoxane (abbreviated as “MAO”), AgSbF ₆ and AgBF ₄ A combination with a compound selected from
A combination of [(η ³ -aryl) PdCl] ₂ and AgSbF ₆ or AgBF ₄ ;
Examples include combinations of [(cycloocta-1,5-diene) Pd (CH ₃ ) Cl], PPh ₃ and NaB [3,5- (CF ₃ ) ₂ C ₆ H ₃ ] ₄ .

(A-3) Multi-component catalyst system (2)
(I) a transition metal compound selected from nickel compounds, cobalt compounds, titanium compounds and zirconium compounds; (II) a compound selected from super strong acids, Lewis acids and ionic boron compounds; and (III) an organoaluminum compound. The combination which consists of these three components is mentioned.

(I) Transition metal compound (I-1) Nickel compound, cobalt compound As nickel compound and cobalt compound, nickel or cobalt organic carboxylate, organic phosphite, organic phosphate, organic sulfonate, β -Compounds selected from diketone compounds and the like, more specifically, for example, nickel 2-ethylhexanoate, nickel naphthenate, cobalt naphthenate, nickel oleate, nickel dodecanoate, cobalt dodecanoate, neodecanoic acid Cobalt, nickel dibutyl phosphite, nickel dibutyl phosphate, nickel dioctyl phosphate, nickel salt of dibutyl phosphate, nickel dodecylbenzenesulfonate, nickel p-toluenesulfonate, bis (acetylacetonato) nickel, bis (ethylacetate) Acete And nickel).

Examples thereof include compounds obtained by modifying the organic carboxylate of nickel with a super strong acid such as hexafluoroantimonic acid, tetrafluoroboric acid, trifluoroacetic acid, and hexafluoroacetone.
Also, nickel diene or triene coordination complexes such as dichloro (1,5-cyclooctadiene) nickel; [(η ³ -crotyl) (1,5-cyclooctadiene) nickel] hexafluorophosphate, and its tetra Fluoroborate complex, tetrakis [3,5-bis (trifluoromethyl)] borate complex; (1,5,9-cyclododecatriene) nickel; bis (norbornadiene) nickel; bis (1,5-cyclooctadiene) nickel And nickel complexes.

Further, complexes in which ligands having atoms such as P, N, and O are coordinated to nickel or cobalt, such as bis (triphenylphosphine) nickel dichloride, bis (triphenylphosphine) nickel dibromide, bis (triphenyl) Phosphine) cobalt dibromide, bis [tri (2-methylphenyl) phosphine] nickel dichloride, bis [tri (4-methylphenyl) phosphine] nickel dichloride, bis [N- (3-t-butylsalicylidene) phenylamido sulfonate] nickel, Ni [PhC (O) CH] (Ph), Ni (OC ( C 6 H 4) PPh) (H) (PCy 3), Ni _{[OC (O) (C 6 H} 4) P ] ( H) (PPh _3), bis (1,5-cyclooctadiene) a reaction product of nickel and PhC (O) CH = PPh _{3 [2,6- (i-Pr) 2 C} 6 H 3 N = CHC 6 H 3 (O) (Anth) ] (Ph) (PPh ₃₎ nickel complex such as Ni (where, Anth is 9-anthracenyl, Ph is phenyl, and Cy is an abbreviation for cyclohexyl).

(I-2) Titanium, zirconium compounds Titanium, zirconium compounds include [t-BuNSiMe (Me ₄ Cp)] TiCl ₂ , (Me ₄ Cp) (O—iPr ₂ C ₆ H ₃ ) ₂ TiCl, (Me ₄ Cp) TiCl ₃ , (Me ₄ Cp) Ti (OBu) ₃ , [t-BuNSiMe ₂ Flu] TiMe ₂ , [t-BuNSiMe ₂ Flu] TiCl ₂ , Et (Ind) ₂ ZrCl ₂ , Ph ₂ C (Ind) (Cp) ZrCl ₂ , iPr (Cp) (Flu) ZrCl ₂ , iPr (3-tert-But-Cp) (Ind) ZrCl ₂ , iPr (Cp) (Ind) ZrCl ₂ , Me ₂ Si (Ind) ₂ ZrCl ₂ , Cp ₂ ZrCl ₂ (Cp is cyclopentadienyl, Ind is indenyl, Flu is an abbreviation for fluorenyl), and the like. The

(II) Super strong acid, Lewis acid and ionic boron compound Examples of super strong acids include hexafluoroantimonic acid, hexafluorophosphoric acid, hexafluoroarsenic acid, trifluoroacetic acid, fluorosulfuric acid, trifluoromethanesulfonic acid, tetrafluoroboric acid, Examples include tetrakis (pentafluorophenyl) boric acid, tetrakis [3,5-bis (trifluoromethyl) phenyl] boric acid, p-toluenesulfonic acid, pentafluoropropionic acid and the like.

  Examples of Lewis acid compounds include complexes of boron trifluoride with ethers, amines, phenols, etc., aluminum trifluoride ethers, complexes of amines, phenols, tris (pentafluorophenyl) borane, tris [3,5 Boron compounds such as bis (trifluoromethyl) phenyl] borane; aluminum compounds such as aluminum trichloride, aluminum tribromide, ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminum fluoride, tri (pentafluorophenyl) aluminum; Organic halogen compounds exhibiting Lewis acidity such as hexafluoroacetone, hexachloroacetone, chloranil, hexafluoromethyl ethyl ketone; Compounds exhibiting Lewis acidity such as titanium tetrachloride and pentafluoroantimony Etc., and the like.

  Examples of the ionic boron compound include triphenylcarbenium tetrakis (pentafluorophenyl) borate, triphenylcarbeniumtetrakis [3,5-bis (trifluoromethyl) phenyl] borate, triphenylcarbeniumtetrakis (2,4 , 6-trifluorophenyl) borate, triphenylcarbenium tetraphenylborate, tributylammonium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, N, N-diethylanilinium tetrakis (Pentafluorophenyl) borate, N, N-diphenylanilinium tetrakis (pentafluorophenyl) borate and the like.

(III) Organoaluminum compound Examples of the organoaluminum compound include alkylalumoxane compounds such as methylalumoxane, ethylalumoxane, and butylalumoxane; trimethylaluminum, triethylaluminum, triisobutylaluminum, diisobutylaluminum hydride, diethylaluminum chloride, Examples include alkylaluminum compounds and halogenated alkylaluminum compounds such as diethylaluminum fluoride, ethylaluminum sesquichloride, and ethylaluminum dichloride; a mixture of the alkylalumoxane compound and the alkylaluminum compound.

These catalyst components are used, for example, in amounts used within the following ranges.
A transition metal compound is 0.02-100 millimol atom with respect to 1 mol of monomers. When the organoaluminum compound is used in combination (multicomponent systems (1) and (2)), the organoaluminum compound is used in an amount of 1 to 5,000 mol per mol of the metal atom of the transition metal compound. Furthermore, when a super strong acid, Lewis acid or ionic boron compound is used in combination (multicomponent system (2)), these compounds are 0.1 to 100 moles per mole of metal atoms of the transition metal compound. .

(B) Polymerization solvent As the solvent used in the addition polymerization reaction, the monomer composition or catalyst to be subjected to the polymerization is dissolved and the catalyst is not deactivated. Although it will not specifically limit if it melt | dissolves, For example, Aliphatic hydrocarbon solvents, such as cyclohexane, cyclopentane, and methylcyclopentane; Aliphatic hydrocarbon solvents, such as hexane, heptane, and octane; Toluene, benzene, xylene, mesitylene And aromatic hydrocarbon solvents such as: halogenated hydrocarbon solvents such as dichloromethane, 1,2-dichloroethane, 1,1-dichloroethane, tetrachloroethane, chlorobenzene, dichlorobenzene, and the like. These can be used alone or in admixture of two or more.

(C) Molecular Weight Modifier In the present invention, the molecular weight of the norbornene addition polymer to be produced can be adjusted by adding hydrogen or α-olefin as a molecular weight regulator in the polymerization system. The molecular weight of the norbornene-based addition polymer produced decreases as the molecular weight regulator added increases.

(Hydrogenation reaction)
The polymer obtained by the ring-opening polymerization reaction has an olefinically unsaturated bond in the molecule. Moreover, also in the said addition polymerization reaction, a polymer may have an olefinically unsaturated bond in the molecule | numerator. Since the olefinically unsaturated bond present in the polymer molecule may cause deterioration such as coloring over time or gelation, it is preferable to perform a hydrogenation reaction that converts this olefinically unsaturated bond to a saturated bond. .

  In the hydrogenation reaction, a known hydrogenation catalyst is added to an ordinary method, that is, a polymer solution containing an olefinically unsaturated bond, and hydrogen gas at atmospheric pressure to 300 atm, preferably 3 to 200 atm, is added thereto. The reaction can be carried out at 0 to 200 ° C, preferably 20 to 180 ° C.

The hydrogenation rate of the hydrogenated polymer is usually 50% or more, preferably 70% or more, more preferably 90% or more, particularly preferably 98% or more, and most preferably 99% as measured by 500 MHz and ¹ H-NMR. That's it. The higher the hydrogenation rate, the more preferable the hydrogenated polymer is because the stability to heat and light is excellent, and stable characteristics can be obtained over a long period of time when used as a molded product.

  When the polymer obtained by the above method has an aromatic group in the molecule, the aromatic group does not cause deterioration such as coloring over time or gelation, but rather is advantageous in mechanical properties and optical properties. Therefore, it is not always necessary to hydrogenate such an aromatic group.

  As a hydrogenation catalyst, what is used for the hydrogenation reaction of a normal olefinic compound can be used. Examples of the hydrogenation catalyst include a heterogeneous catalyst and a homogeneous catalyst.

  Examples of the heterogeneous catalyst include a solid catalyst in which a noble metal catalyst material such as palladium, platinum, nickel, rhodium, and ruthenium is supported on a carrier such as carbon, silica, alumina, and titania. Homogeneous catalysts include nickel naphthenate / triethylaluminum, nickel acetylacetonate / triethylaluminum, cobalt octenoate / n-butyllithium, titanocene dichloride / diethylaluminum monochloride, rhodium acetate, chlorotris (triphenylphosphine) rhodium, dichloro Examples thereof include tris (triphenylphosphine) ruthenium, chlorohydrocarbonyltris (triphenylphosphine) ruthenium, dichlorocarbonyltris (triphenylphosphine) ruthenium, and the like. These catalysts may be powder or granular.

These hydrogenation catalysts are usually used in a ratio such that the weight ratio of the ring-opening polymer to the hydrogenation catalyst (ring-opening polymer: hydrogenation catalyst) is 1: 1 × 10 ⁻⁶ to 1: 2. The
(Characteristics of norbornene resin)
The norbornene-based resin used in the present invention has an intrinsic viscosity [η] _inh in chloroform at 30 ° C. of preferably 0.2 to 2.0 dl / g, more preferably 0.35 to 1.0 dl / g, particularly preferably. Is 0.4 to 0.85 dl / g, and the polystyrene-reduced number average molecular weight (Mn) measured by GPC is preferably 5,000 to 1,000,000, more preferably 10,000 to 500,000, particularly preferably 15,000. It is desirable that the weight average molecular weight (Mw) is 10,000 to 2,000,000, more preferably 20,000 to 1,000,000, and particularly preferably 30,000 to 500,000. When the intrinsic viscosity [η] _inh , the number average molecular weight, and the weight average molecular weight are in the above ranges, the norbornene resin is excellent in mechanical strength and can be easily damaged.

  The glass transition temperature (Tg) of the norbornene resin is usually 120 ° C. or higher, preferably 130 ° C. or higher. When Tg is within the above range, a norbornene-based resin film having high reliability even in long-term use can be obtained.

Further, the water vapor permeability of the norbornene-based resin is preferably 5 to 200 (g) as a value measured in accordance with the humidity sensor method of JIS K7129 under the conditions of a measurement temperature of 40 ° C. and a relative humidity of 90% RH. · 25 µm / m ² · 24 hr), particularly preferably 50 to 150 (g · 25 µm / m ² · 24 hr). If the water vapor transmission rate is less than 5 (g · 25 μm / m ² · 24 hr), it is not preferable because moisture drying of the polarizing film is not successful during the production of the polarizing plate. On the other hand, if it exceeds 200 (g · 25 μm / m ² · 24 hr), water permeates into the polarizing film inside the polarizing plate in a high-temperature and high-humidity atmosphere, which is not preferable.

(Benzotriazole UV absorber)
In the present invention, it is preferable that at least one norbornene-based resin film contains a benzotriazole-based ultraviolet absorber. In this case, a benzotriazole ultraviolet absorber is added to the norbornene resin. The ultraviolet absorber absorbs ultraviolet rays, thereby suppressing the generation of active radical species that cause the norbornene-based resin to deteriorate, preventing coloring and transparency from being deteriorated, and preventing ultraviolet rays from being applied to the polarizing film. It has a role of inhibiting transmission and preventing deterioration of the polarizing film.
The melting point of the benzotriazole ultraviolet absorber is preferably Tg−35 ° C. to Tg + 75 ° C., particularly preferably Tg−30 ° C. to Tg + 70 ° C. with respect to the glass transition temperature (Tg) of the norbornene resin. When the melting point is lower than Tg-35 ° C., there is a problem that the volatility of the ultraviolet absorber is increased and the ultraviolet absorber or a decomposition product thereof adheres to a film or a film forming machine. On the other hand, if the melting point is higher than Tg + 75 ° C., the ultraviolet absorber bleeds on the film surface during film molding and the like, and the melting point is high during the cooling process, so it cannot be compatible and solidifies on the surface. There is a problem of sticking.

Examples of the benzotriazole ultraviolet absorber include 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- [2H-benzotriazol-2-yl] phenol] 2- (2H-1,2,3-benzotriazol-2-yl) -4,6-di-tert-butylphenol, 2- (2-hydroxy-5-tert-butylphenyl) -2H-benzotriazole, 2- ( 3,5-di-tert-butyl-2-hydroxyphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis- (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- [2′-hydroxy-3 ′-(1-methyl-1-phenylethyl) -5 ′-(1,1,3,3-tetramethylbutyl) -benzotriazole and the like.
Of these, 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- [2H-benzotriazol-2-yl] phenol] is particularly preferably used.
In the present invention, an ultraviolet absorber other than benzotriazole may be used in combination as the ultraviolet absorber. Examples of ultraviolet absorbers that may be used in combination include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, tetrakis [methylene-3- (3,5-ditert-butyl-4hydroxyphenyl) propionate. ] Methane etc. are mentioned.
The addition amount of the ultraviolet absorber is usually 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the norbornene resin. When the addition amount of the ultraviolet absorber is less than 0.1 parts by weight, a sufficient ultraviolet absorption effect is not seen, and the effect of the present invention is hardly exhibited. Moreover, when it exceeds 20 weight part, the light transmittance in the visible region of the obtained film may fall.
Moreover, the ratio of the benzotriazole type | system | group ultraviolet absorber in a total ultraviolet absorber is 10 weight% or more normally, Preferably it is 50 weight% or more.

(Other ingredients)
In the present invention, an additive such as an antioxidant can be further added to the norbornene-based resin as long as the effects of the present invention are not impaired.

  Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3,3′-di-t-butyl-5,5′-dimethyldiphenylmethane, tetrakis [Methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane.

  Moreover, when manufacturing a norbornene-type resin film by the solution casting method mentioned later, manufacture of a resin film can be made easy by adding a leveling agent and an antifoamer.

  These additives may be mixed with the norbornene resin or the like when producing the norbornene resin film used in the present invention, or may be blended in advance by adding when producing the norbornene resin. . The addition amount is appropriately selected according to the desired properties, but is usually 0.01 to 5.0 parts by weight, preferably 0.05 to 2.0 parts by weight, with respect to 100 parts by weight of the norbornene resin. It is desirable that

(Manufacturing method of norbornene resin film)
The norbornene-based resin film used in the present invention is cast (cast-molded) by directly melt-molding the norbornene-based resin or the resin composition containing the norbornene-based resin and the additive, or by dissolving in a solvent. ) Can be suitably formed.

(A) Melt Molding The norbornene resin film used in the present invention can be produced by melt extrusion molding the norbornene resin or the resin composition containing the norbornene resin and the additive.

(B) Casting The norbornene-based resin film used in the present invention removes the solvent by casting the liquid resin composition in which the norbornene-based resin and, if necessary, the additive are dissolved in a solvent, onto an appropriate base material. It can also be manufactured. For example, the liquid resin composition is applied onto a substrate such as a steel belt, a steel drum, or a polyester film, the solvent is dried, and then the coating film is peeled from the substrate to obtain a norbornene resin film. Obtainable.

  The amount of residual solvent in the norbornene-based resin film obtained by the above method is preferably as small as possible, usually 3% by weight or less, preferably 1% by weight or less, and more preferably 0.5% by weight or less. When the residual solvent amount is within the above range, the norbornene-based resin film having a desired function can be obtained because the film is less likely to be deformed or changed with time.

  Although the thickness of the norbornene-type resin film used by this invention is not specifically limited, Usually, 5-500 micrometers, Preferably it is 10-150 micrometers, More preferably, it is desirable that it is 20-100 micrometers. When the thickness of the film is in the above range, a film having sufficient strength can be obtained, and a film having good birefringence, transparency, and appearance can be obtained.

The norbornene resin film used in the present invention desirably has a light transmittance of usually 80% or more, preferably 85% or more, more preferably 90% or more.
Moreover, the norbornene-type resin film used by this invention may give the surface treatment in order to improve adhesiveness with the adhesive bond layer mentioned later. Examples of the surface treatment include primer treatment, plasma treatment, corona treatment, alkali treatment, and coating treatment.

Of the above surface treatments, the norbornene resin film and the adhesive layer can be firmly adhered by using corona treatment, among others. The corona treatment conditions in this case, the irradiation amount of the corona discharge electrons preferably ^{1~1000W / m 2 / min, 10~100W} / m 2 / min is more preferred. When the irradiation amount is in the above range, the treatment effect does not reach the inside of the film, and a sufficient surface modification effect can be obtained without altering the film. Further, this corona treatment may be performed not only on the surface in contact with the adhesive layer but also on the opposite surface.

<Method for producing retardation film>
The norbornene-based resin film used in the present invention can be used as a retardation film by performing a stretching treatment.

As a stretching method, a method of stretching the resin film uniaxially or biaxially is used.
In the case of the uniaxial stretching treatment, the stretching speed is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, and more preferably 100 to 1,000% / min.

  In the case of the biaxial stretching treatment, a method of simultaneously stretching in two directions, or a method of performing a stretching treatment in a direction different from the direction of the stretching treatment after the uniaxial stretching treatment can be applied. At this time, the intersection angle of the two stretching axes is appropriately determined according to the characteristics required for the target optical film (retardation film), and is not particularly limited, but is usually in the range of 60 to 120 degrees. The stretching speed is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably 100 to 1,000% / min, and particularly preferably 100 to 1,000% / min. It is 500% / min, and may be the same or different in each stretching direction.

  The stretching treatment temperature is not particularly limited, but based on the glass transition temperature (Tg) of the norbornene-based resin to be used, Tg ± 30 ° C., preferably Tg ± 15 ° C., more preferably Tg−5 to Tg + 15 ° C. Range. By setting the stretching treatment temperature within the above range, it is possible to suppress the occurrence of uneven retardation in the stretched film obtained, and it is preferable in that the refractive index ellipsoid can be easily controlled.

  The draw ratio is appropriately determined according to the properties required for the target optical film, and is not particularly limited, but is usually 1.01 to 10 times, preferably 1.03 to 5 times, and more preferably 1.03. ~ 3 times. When the draw ratio is in the above range, the retardation of the obtained stretched film can be easily controlled. Although the stretched film may be cooled as it is, it is cooled after being held in a temperature atmosphere of Tg-20 ° C. to Tg for at least 10 seconds, preferably 30 seconds to 60 minutes, more preferably 1 to 60 minutes. It is preferable to do. Thereby, a stable retardation film can be obtained with little change over time in the retardation of transmitted light.

  The film subjected to the stretching treatment as described above can give a retardation to transmitted light as a result of the orientation of the molecules by the stretching treatment. This retardation is determined by the stretching ratio, the stretching temperature, or the thickness of the film. It can be controlled by such factors.

  The thickness of the norbornene-based resin film used as the retardation film is not particularly limited, but is usually 5 to 500 μm, preferably 10 to 150 μm, and more preferably 20 to 100 μm.

<Adhesive>
In the present invention, the norbornene resin film and the polarizing film are bonded using an adhesive. The adhesive is not particularly limited, but an ultraviolet curable adhesive such as a composition of an ultraviolet polymerizable polymer and / or an ultraviolet polymerizable monomer and an ultraviolet polymerization initiator; an aqueous polyvinyl alcohol solution, a polyvinyl alcohol, and a polyurethane resin. In particular, an aqueous adhesive such as an aqueous solution of an epoxy curing agent is preferably used.

<Polarizing film>
The polarizing film used in the present invention has a function as a polarizing film, that is, a film having a function of dividing incident light into two polarization components orthogonal to each other, allowing only one of them to pass, and absorbing or dispersing the other components. If it is, it will not specifically limit, Any polarizing film can be used.

  Examples of the polarizing film that can be used in the present invention include polyvinyl alcohol (hereinafter abbreviated as “PVA”) / iodine polarizing film; PVA / dye polarizing film in which a dichroic dye is adsorbed and oriented on a PVA film. A polyene polarizing film in which a polyene is formed by a dehydration reaction of a PVA film or a dehydrochlorination reaction of a polyvinyl chloride film; the surface and / or the inside of a PVA film composed of a modified PVA containing a cationic group in the molecule And a polarizing film having a dichroic dye. Of these, PVA / iodine polarizing films are preferred.

  The manufacturing method of the polarizing film used by this invention is not specifically limited, A conventionally well-known method is applicable. For example, a method of adsorbing iodine ions after stretching a PVA film, a method of stretching a PVA film after dyeing with a dichroic dye, a method of stretching a PVA film and then dyeing with a dichroic dye, two colors Examples thereof include a method of stretching a sexual dye on a PVA film and then stretching, a method of printing a dichroic dye after stretching a PVA film, and the like. More specifically, iodine is dissolved in a potassium iodide solution to form higher-order iodine ions, the ions are adsorbed on a PVA film and stretched, and then a 1 to 5% by weight boric acid aqueous solution has a bath temperature of 30. A method for producing a polarizing film by immersing at ~ 40 ° C; or, after treating a PVA film with boric acid in the same manner as described above and stretching it about 3 to 7 times in a uniaxial direction, 0.05 to 5% by weight of two colors And a method of producing a polarizing film by immersing in an aqueous dye solution at a bath temperature of 30 to 40 ° C. to adsorb the dye, followed by drying at 80 to 100 ° C. and heat setting.

The thickness of the polarizing film used in the present invention is not particularly limited, but is 10 to 50 μm, preferably 15 to 45 μm.
These polarizing films may be used as they are for the production of the polarizing plate according to the present invention, but can also be used after being subjected to corona discharge treatment or plasma treatment on the surface in contact with the adhesive layer.

<Polarizing plate>
The polarizing plate of the present invention is a polarizing plate in which the norbornene resin film is bonded to both surfaces of the polarizing film, preferably via the adhesive. The norbornene-based resin film is one in which at least one layer contains a benzotriazole-based ultraviolet absorber, and preferably the norbornene-based resin film that is not in contact with the liquid crystal cell contains the ultraviolet absorber. Preferably, the norbornene resin film on both sides contains the ultraviolet absorber.

  The method for producing such a polarizing plate is not particularly limited. For example, an adhesive is uniformly applied to one surface of a norbornene-based resin film or a polarizing film, and the other film (film) is overlaid on the coated surface to roll. And a method of heating or exposing as necessary.

  At this time, the adhesive may be applied so that the thickness of the adhesive layer after drying is preferably 0.01 to 50 μm, more preferably 0.01 to 30 μm, and particularly preferably 0.01 to 3 μm. preferable. When the thickness of the adhesive layer after drying is in the above range, the transparency of the polarizing plate is maintained, and the norbornene-based resin film and the polarizing film are bonded with sufficient adhesive force, and these delaminations are unlikely to occur. .

  The temperature at the time of application of the adhesive is usually in the range of 15 to 40 ° C, and the bonding temperature is usually in the range of about 15 to 30 ° C. When an ultraviolet curable adhesive is used as the adhesive, an exposure process is performed after bonding to cure the adhesive. The exposure light source at this time is not particularly limited, but is preferably ultraviolet light. The exposure amount is preferably 1 to 2000 mJ.

  The polarizing plate according to the present invention has a good polarizing function, excellent properties such as heat resistance and chemical resistance, and is not easily peeled off, deformed or changed in polarization degree even in long-term use, and has high reliability. And has excellent durability. Such a polarizing plate can be suitably used for applications such as a liquid crystal display device.

<Adhesive layer and production method thereof>
The adhesion layer which concerns on this invention contains the polymer derived from the at least 1 sort (s) of alkyl (meth) acrylate represented by the said Formula (i).
In said formula (i), as a C1-C12 alkyl group represented by R ', a methyl group, an ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group , T-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group and the like. Of these, an n-butyl group is particularly preferred. Moreover, the alkyl (meth) acrylate represented by the said formula (i) may be included as a monomer, and may be included 2 or more types.
The polymer contained in the adhesive layer according to the present invention may contain a monomer other than alkyl (meth) acrylate. Monomers other than alkyl (meth) acrylate are preferably unsaturated carboxylic acids, for example, α-β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and itaconic acid; 2-hydroxyethyl (meth) acrylate, 2 -Other (meth) acrylates such as hydroxypropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, glycidyl (meth) acrylate; other ethylenics such as vinyl acetate, vinyl propionate, acrylonitrile, styrene, vinyltoluene Examples thereof include compounds having an unsaturated double bond.

The weight average molecular weight in terms of polystyrene measured by GPC of the polymer constituting the adhesive layer according to the present invention is 1,500,000 or more. Preferably, it is 1,500,000 to 5,000,000, particularly preferably 1,500,000 to 3,000,000. By containing a polymer having a molecular weight of 1,5,000,000 or more, adhesion to norbornene-based resin films is enhanced, and even if stored for a long time under high temperature and high humidity, foaming and peeling do not occur, and long-term reliability A polarizing plate having excellent properties can be obtained.
Moreover, it is preferable that the glass transition temperature (Tg) of the polymer which comprises an adhesion layer is -50 degreeC or more, Most preferably, it is -50 degreeC--25 degreeC.
Although the thickness of the adhesion layer which concerns on this invention is not specifically limited, Usually, 5-50 micrometers, Preferably it is 10-40 micrometers, More preferably, it is desirable that it is 20-30 micrometers. If the thickness of the pressure-sensitive adhesive layer is less than 5 μm, the volume change of the polarizing plate cannot be followed, and there is a risk that floating or peeling will occur. On the other hand, if it exceeds 50 μm, the optical properties may be deteriorated.

  The pressure-sensitive adhesive layer according to the present invention can be obtained by applying a pressure-sensitive adhesive composition obtained by adding a curing agent and an organic solvent to the above polymer, if necessary, and drying it. Furthermore, you may mix | blend polyfunctional (meth) acrylate, a silane coupling agent, etc. as needed. When adhering the polarizing plate to the substrate via the adhesive layer, the adhesive layer surface is pressed against the substrate and bonded by heating and pressing as necessary.

As said hardening | curing agent, an isocyanate compound <A>, an epoxy compound <B>, an aldehyde compound <C>, an amine compound <D> etc. are illustrated as a preferable thing.
<A> As the isocyanate compound, tolylene diisocyanate, tolylene diisocyanate hydride, tolylene diisocyanate adduct of trimethylolpropane, xylylene diisocyanate adduct of trimethylolpropane, triphenylmethane triisocyanate, methylenebis (4-phenylmethane) ) Triisocyanate, isophorone diisocyanate and the like.
<B> As epoxy compounds, bisphenol A / epichlorohydrin type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylol Propane triglycidyl ether, diglycidyl aniline, diglycidyl amine, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N′-diglycidylaminomethyl) cyclohexane, etc. Can be mentioned.
Examples of the <C> aldehyde compound include glyoxal, malondialdehyde, succindialdehyde, maleindialdehyde, glutardialdehyde, formaldehyde, acetaldehyde, benzaldehyde and the like.
Examples of the <D> amine compound include hexamethylenediamine, triethyldiamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethyltetramine, isophoronediamine, amino resin, melamine resin, and the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited at all by this Example. In the following description, “part” means “part by weight” unless otherwise specified.
Further, the glass transition temperature, moisture permeability, single transmittance, polarization degree measurement, moisture resistance test, dry heat test, and UV resistance test were carried out by the following methods.
<Glass transition temperature (Tg)>
Using a differential scanning calorimeter (DSC) manufactured by Seiko Instruments Inc., the glass transition temperature (hereinafter also referred to as “Tg”) was measured in a nitrogen atmosphere under a temperature rising rate of 20 ° C./min.
<Moisture permeability>
Measurement was performed using L80-4000 manufactured by LYSSY under the conditions of a measurement temperature of 40 ° C. and a relative humidity of 90% RH in accordance with the JIS K7129 humidity sensor method.
<Single transmittance>
The single transmittance of the polarizing plate was measured using a spectrophotometer V7300 manufactured by JASCO Corporation.
<Degree of polarization>
The polarization degree of the polarizing plate was measured using a spectrophotometer V7300 manufactured by JASCO Corporation.

<Moist heat test>
After pasting a polarizing plate with an adhesive layer on the glass for LCD, and storing it for 500 hours in an environment of 85 ° C. and 85% relative humidity, the degree of polarization is measured and it is visually observed that the adhesive layer is not lifted off. Evaluated. The degree of polarization was evaluated according to the following standard (1) from the value of the amount of change in the degree of polarization before and after the durability test represented by the following formula. Moreover, about the peeling of the adhesion layer, the following reference | standard (2) evaluated.
<Dry heat test>
After sticking the polarizing plate which has the adhesion layer on the glass for LCD, it preserve | saved for 500 hours in the environment of temperature 95 degreeC, Then, the polarization degree measurement and the absence of peeling of the adhesion layer were evaluated visually. The degree of polarization was evaluated according to the following standard (1) from the value of the amount of change in the degree of polarization before and after the durability test represented by the following formula. Moreover, about the peeling of the adhesion layer, the following reference | standard (2) evaluated.
<UV resistance test>
After pasting the polarizing plate having the adhesive layer on the glass for LCD, 1000 hours from the top surface of the polarizing plate (the surface of the following film 1) using a fade meter manufactured by Suga Test Instruments Co., Ltd. After irradiating with ultraviolet rays, the degree of polarization was measured and the adhesion layer was not visually lifted off. The degree of polarization was evaluated according to the following standard (1) from the value of the amount of change in the degree of polarization before and after the durability test represented by the following formula. Moreover, about the peeling of the adhesion layer, the following reference | standard (2) evaluated.
[Standard (1)]
○: Change in polarization degree is less than 0.5% Δ: Change in polarization degree is from 0.5% to less than 2.0% ×: Change in polarization degree is 2.0% or more [Change in polarization degree ] = (1− [degree of polarization after test] / [initial degree of polarization]) × 100 (%)
[Standard (2)]
○: There is no floating, peeling or foaming of the adhesive layer. Δ: One or two floating, peeling or foaming is observed on the edge or in the surface of the adhesive layer. X: Three or more floating or peeling in the adhesive layer. , Foaming is seen

[Synthesis Example 1]
(Synthesis of norbornene resin)
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 227.5 parts, bicyclo [2.2.1] hept-2-ene 22.5 parts, 1-hexene (molecular weight regulator) 18 parts, toluene (for ring-opening polymerization reaction) (Solvent) 750 parts were charged into a nitrogen-substituted reaction vessel, and this solution was heated to 60 ° C. Next, 0.62 part of a toluene solution of triethylaluminum (1.5 mol / l) and tungsten hexachloride modified with t-butanol / methanol (t-butanol: methanol: tungsten) were added to the solution in the reaction vessel. 37 parts of a toluene solution (concentration 0.05 mol / l) of 35 mol: 0.3 mol: 1 mol) was added, and this system was heated and stirred at 80 ° C. for 3 hours to cause a ring-opening polymerization reaction. Thus, a ring-opening copolymer solution was obtained. The polymerization conversion rate in this polymerization reaction was 97%.

The autoclave was charged with 4,000 parts of the ring-opening copolymer solution thus obtained, and RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ 0.48 part was added to the ring-opening copolymer solution. And the hydrogenation reaction was carried out by heating and stirring for 3 hours under the conditions of a hydrogen gas pressure of 100 kg / cm ² and a reaction temperature of 160 ° C.
After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. The reaction solution was poured into a large amount of methanol to separate and collect the coagulated product, and dried to obtain a hydrogenated cyclic olefin resin A. The Tg of Resin A was 140 ° C. Moreover, Mn, Mw, and Mw / Mn in terms of polystyrene measured by the GPC method were 24,000, 67,000, and 2.8, respectively, and the intrinsic viscosity (η _inh ) was 0.49 dl / g. . Further, the moisture permeability of the resin A was 110 (g · 25 μm / m ² · 24 hr).

[Production Example 1]
Using a twin screw extruder, 0.3 parts of (pentaerythrityltetrakis-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate: melting point 115 ° C.) with respect to 100 parts of resin A, As a benzotriazole compound, (2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol]: melting point 199 ° C.) After melt-kneading at 270 ° C. at a blending ratio of 5 parts, the mixture was extruded onto a strand, cooled with water, and then pellets were obtained through a feeder ruler. The obtained pellets were circulated and dehumidified and dried at 100 ° C. for 3 hours under nitrogen, then sent to a hopper and melted at a resin temperature of 270 ° C. using a single screw extruder having a screw diameter of 75 mmφ.
This molten resin was guided to a 700 mm wide coat hanger die through a polymer filter (aperture 5 μm) heated to 280 ° C. at a rate of 30 kg / hr by a double shaft discharge type gear pump. The differential pressure between the inlet and outlet of the filter was 3 MPa. The die heater was set to 250 ° C. using an aluminum cast heater, and a lip heater was installed in addition to the front lip portion to control the die lip temperature to 250 ± 0.4 ° C.
The lip opening was set to 0.5 mm in the width direction, and fine adjustment was performed by measuring thickness unevenness with an on-line thickness gauge installed on the downstream side of melt extrusion. The resin coming out of the die is dropped in the lead direct wire direction of a 250 mmφ cast roll (surface roughness: 0.1 μm), pressed in order with two cooling rolls installed horizontally to the cast roll axis, and then peeled off. A film (1) having a thickness of 80 μm was obtained by controlling the tension with 4 kgf.

<Stretching of film>
The stretched film (2) was obtained by heating a film (1) to 145 degreeC and performing a longitudinal uniaxial stretching 1.3 times. The obtained stretched film (2) had a thickness of 70 μm, a total light transmittance of 93%, and a phase difference at a wavelength of 590 nm measured using “KOBRA-21ADH” manufactured by Oji Scientific Instruments Co., Ltd. was 141 nm.

[Production Example 2]
A film (3) having a thickness of 80 μm was obtained in the same manner as in Production Example 1 except that the benzotriazole compound was not used. The film (3) was heated to 145 ° C. and longitudinally uniaxially stretched 1.3 times to obtain a stretched film (4). The stretched film (4) obtained had a thickness of 70 μm, a total light transmittance of 93%, and a phase difference at a wavelength of 590 nm measured using “KOBRA-21ADH” manufactured by Oji Scientific Instruments Co., Ltd. was 145 nm.

[Preparation Example 1]
(Preparation of adhesive composition C-1)
A reaction vessel in which 206 parts of acetone, 210 parts of butyl acrylate and 1.2 parts of acrylic acid were purged with nitrogen was charged, and this solution was heated to 55 ° C. and then 2,2′-azobis (2,4-dimethyl) as an initiator. A solution of 0.021 part of valeronitrile) in 5 parts of acetone was added. At this time, the concentration of the monomer was 50%. After stirring for 1 hour, acetone was added dropwise over 8 hours under a temperature condition of 55 ° C. to adjust the monomer concentration to 35%. After completion of the dropwise addition, the mixture was stirred for 3 hours under the condition of a reaction temperature of 55 ° C., and then ethyl acetate was added to adjust the monomer concentration to 20%. The viscosity of the obtained polymer solution was 18,400 mPa · s, and the weight average molecular weight in terms of polystyrene by GPC of the polymer was about 1,570,000.
With respect to the solid content of 100 parts of the obtained polymer solution, 4 parts of an isocyanate-based crosslinking agent and 0.4 part of a silane coupling agent were added and stirred sufficiently, and then defoamed using an applicator. A pressure-sensitive adhesive sheet is obtained by coating the release surface of a treated polyethylene terephthalate film (trade name: PET3811, manufactured by Lintec Co., Ltd.) so that the thickness after drying is 25 μm, and drying at 90 ° C. for 1 minute. It was.
[Preparation Example 2]
(Preparation of adhesive composition C-2)
A polymer solution was obtained in the same manner as in Preparation Example 1, except that the amount of initiator added was 0.148 parts. The viscosity of the obtained polymer solution was 1,950 mPa · s, and the weight average molecular weight in terms of polystyrene by GPC was about 780,000.
An adhesive sheet was obtained in the same manner as in Preparation Example 1 by using the solution obtained by adding an isocyanate-based crosslinking agent and a silane coupling agent to the obtained polymer solution and stirring sufficiently, as in Preparation Example 1. It was.

[Preparation Example 3]
(Preparation of adhesive)
An aqueous solution having a solid content concentration of 7% by weight by adding water to 163-030545 (polystyrene equivalent weight average molecular weight 22,000, saponification degree 88 mol%) manufactured by Wako Pure Chemical Industries, Ltd., which is a polyvinyl alcohol resin. Was prepared. On the other hand, 100 parts of WLS-201 (solid concentration 35% by weight) manufactured by Dainippon Ink and Chemicals, which is a polyurethane resin, is added to CR- manufactured by Dainippon Ink & Co., which is a polyepoxy curing agent. 5 L (100% active ingredient product) 5 parts was blended and diluted with water to prepare an aqueous solution with a solid content of 20% by weight. The obtained polyurethane resin aqueous solution and polyvinyl alcohol resin aqueous solution were mixed at a weight ratio of 1: 1 (solid content weight ratio of 80:20), and a mixed adhesive having a solid content concentration of 15% by weight was obtained. Prepared.

[Examples 1-4, Comparative Examples 1-3]
Polyvinyl alcohol (hereinafter abbreviated as “PVA”) was drawn in a dyeing bath at a temperature of 30 ° C. consisting of an aqueous solution having an iodine concentration of 0.03% by weight and a potassium iodide concentration of 0.5% by weight. Pre-stretching at 3 times, then post-stretching at a stretching ratio of 2 in a 55 ° C. crosslinking bath comprising an aqueous solution having a boric acid concentration of 5% by weight and a potassium iodide concentration of 8% by weight. Then, a polarizing film was obtained by drying treatment. On both surfaces of the obtained polarizing film, the film obtained in the production example is arranged so as to be film (a) / polarizing film / film (b) via the mixed adhesive obtained in Preparation Example 3. The combination shown in 1 was adhered. In addition, as a film (5) in a table | surface, the cellulose resin film "TDY80uL" by the Fuji Film company was used. The film (5) had a moisture permeability of 700 (g · 25 μm / m ² · 24 hr) and a thickness of 80 μm. Table 1 shows the single transmittance and polarization degree of the obtained polarizing plate.
After sticking the adhesive surface of the adhesive sheet obtained in Preparation Example 1 or 2 on the surface of the polarizing film film (b) with a laminator, the adhesive layer was aged at 23 ° C. × 65% for 7 days. The provided polarizing plate was obtained. The obtained polarizing plate was subjected to a wet heat test, a dry heat test, and a UV resistance test. The results are also shown in Table 1.

Claims (5)

A norbornene-based resin film (a) and a norbornene-based resin film (b) are respectively laminated on both surfaces of the polarizing film, and the surface of the norbornene-based resin film (b) opposite to the polarizing film is represented by the following formula (i). An adhesive layer containing a polymer having a structural unit derived from at least one alkyl (meth) acrylate and having a polystyrene-equivalent weight average molecular weight of 1,500,000 or more by gel permeation chromatography. A polarizing plate characterized by comprising:
CH ₂ = CRCOOR '(i)
(In formula (i), R represents a hydrogen atom or a methyl group, and R ′ represents an alkyl group having 1 to 12 carbon atoms.) The norbornene-based resin film is a film made of a resin obtained by (co) polymerizing a monomer containing at least one compound represented by the following formula (1). The polarizing plate as described in.

(In the formula (1), R ^{1 to} R ⁴ each independently represent a hydrogen atom, a halogen atom, or a monovalent group that may contain oxygen, nitrogen, sulfur or silicon. R ¹ and R ² Or R ³ and R ⁴ may be bonded to each other to form an alkylidene group, or R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ may be bonded to each other. And may form a monocyclic or polycyclic carbocyclic or heterocyclic ring, where x is 0 or an integer of 1 to 3, and y is 0 or 1.) The polarizing plate according to claim 1, wherein a hard coat layer is laminated directly or via another layer on the surface of the norbornene-based resin film (a) opposite to the polarizing film. The polarizing plate according to claim 1, wherein at least one norbornene-based resin film is a retardation film. The polarizing plate according to claim 1, wherein at least one norbornene-based resin film contains a benzotriazole-based ultraviolet absorber.