JP4635968B2 - Thermoplastic norbornene resin-based optical film - Google Patents

Description

  The present invention relates to an optical film mainly composed of a specific thermoplastic norbornene resin. More specifically, the present invention is easily obtained by stretching the function of giving a phase difference to transmitted light, and is excellent in durability stability of the function of giving a phase difference to the obtained transmitted light. In addition, the present invention relates to an optical film having good adhesion and adhesion to other materials, high transparency, and excellent heat resistance. The present invention also relates to an optical film having functions such as retardation, light diffusion function, transparent conductivity, and antireflection function.

A polycarbonate or polyester film that has been conventionally used as an optical film can be easily obtained by stretching when imparting a function of imparting a phase difference to transmitted light. The function of giving a phase difference is rarely insufficient depending on the application, but the anisotropy of the refractive index is too large, that is, the values of the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) are too large. For this reason, the function of giving a phase difference to transmitted light greatly changes due to a slight change in stress, and there is a problem in the reliability and durability stability of the function. In the case of a triacetyl acetate film, although the refractive index anisotropy is small, there are problems such as heat resistance and water absorption deformation.

  Cyclic polyolefin resins have a high glass transition temperature due to the rigidity of the main chain structure, and are amorphous and have high light transmittance due to the presence of bulky groups in the main chain structure, and an anisotropic refractive index. It has features such as low birefringence due to its low properties, and has attracted attention as a transparent thermoplastic resin excellent in heat resistance, transparency and optical properties. Examples of such cyclic polyolefin-based resins include JP-A-1-132625, JP-A-1-132626, JP-A-62-221826, JP-A-2-133413, JP-A-612020816. No. 1, JP-A 61-115912, and the like.

And in recent years, utilizing the above-mentioned characteristics, for example, in the fields of optical films, optical discs, optical lenses, optical materials such as optical fibers, sealing materials such as optical semiconductor sealing, etc., cyclic polyolefin-based resins can be applied. Is being considered.
That is, in order to improve the problems of the conventional optical film, films made of cyclic polyolefin resins have been proposed as various optical films. For example, JP-A-4-245202, JP-A-4-36120, JP-A-5-2108, and JP-A-5-64865 describe a retardation plate made of a cyclic polyolefin resin film. Has been. JP-A-5-212828, JP-A-6-511117 and JP-A-7-77608 describe the use of a cyclic polyolefin resin film as a protective film for a polarizing plate. Further, JP-A-5-61026 discloses a liquid crystal display element substrate made of a film of a cyclic polyolefin resin.

  In these publications, it is described that a cyclic polyolefin resin having a water absorption rate of 0.05% or less can be easily obtained and is characterized by this low water absorption. However, when such a low water-absorbing cyclic polyolefin resin film is used as, for example, a retardation plate or a substrate for a liquid crystal display element, adhesion of a hard coat, an antireflection film or a transparent conductive layer, or a polarizing plate There may be problems with adhesion to glass and glass. Moreover, when using as a protective film of a polarizing plate, in addition to said problem, the problem that the water of the water-system adhesive agent normally used for bonding with a polarizer is hard to dry also arises.

On the other hand, cyclic polyolefin-type resin consists of a wide range structure, and not all become a water absorption 0.05% or less. In order to reduce the water absorption rate to 0.05% or less, the cyclic polyolefin-based resin needs to have a polyolefin structure composed of only carbon atoms and hydrogen atoms or a structure partially containing halogen.
Therefore, in order to solve the problem due to the low water absorption, an optical film containing a thermoplastic norbornene resin in which a polar group is introduced into the molecule is disclosed in JP-A-7-287122 and JP-A-7-287123. It is described in.
The optical films described in these are excellent in optical properties such as high transparency, low retardation of transmitted light, and a function of giving uniform and stable retardation to transmitted light when stretched and oriented, heat resistance, other materials Adhesiveness and adhesiveness are good, and water absorption deformation is small.

However, since these conventional cyclic polyolefin-based resins have too small anisotropy of refractive index, that is, the values of the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) are too small, for example, such cyclic polyolefin resin If an optical film containing a resin is to be provided with a function of imparting a retardation to transmitted light, the conditions for stretching and orientation of the film are limited, and the function of imparting a retardation to transmitted light obtained by stretching and orientation is not satisfactory. Sufficient, i.e., it is difficult to obtain transmitted light having a high phase difference.

  Therefore, the problem of the present invention is to show the excellent characteristics of a film made of a conventional cyclic polyolefin resin, that is, a function of giving a uniform and stable phase difference to transmitted light when it is highly transparent and stretched, In addition, while maintaining the properties of good heat resistance, adhesion to other materials, adhesion, etc., and low water absorption deformation, it has moderate refractive index anisotropy, making stretching orientation easy and stretching An object of the present invention is to provide an optical film mainly composed of a cyclic polyolefin (thermoplastic norbornene) -based resin that can obtain transmitted light having a high retardation by orientation.

  The present invention provides the following general formula (1):

［式中、ｎは０又は１であり、ｍは０又は１以上の整数である。Ｘは独立に式：−CH=CH−で表される基又は式：−CH₂CH₂−で表される基であり、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は各々独立に水素原子；ハロゲン原子；酸素、窒素、イオウ又はケイ素を含む連結基を有していてもよい置換又は非置換の炭素原子数１〜３０の炭化水素基；又は極性基を表し、あるいはＲ^１とＲ^２、Ｒ^３とＲ^４、又はＲ^２とＲ^３とが相互に結合して炭素環又は複素環（これらの炭素環又は複素環は単環構造でもよいし、他の環が縮合して多環構造を形成してもよい。）を形成してもよい。形成される炭素環又は複素環は芳香環でもよいし非芳香環でもよい。］
で表される構造単位ａを含む重合体からなり、該重合体に含まれる構造単位ａの少なくとも一部において、Ｒ¹〜Ｒ^４の少なくとも１つが下記一般式（２）で表される基を有しているか、あるいは、Ｒ^２とＲ^３とが相互に結合して形成される、下記一般式（３）又は（４）から選ばれた少なくとも一つの基を有しており、光弾性係数（Ｃ_Ｐ）が０〜１００（×１０^−１２Ｐａ^−１）であり、かつ応力光学係数（Ｃ_Ｒ）が１５００〜４０００（×１０^−１２Ｐａ^−１）である熱可塑性ノルボルネン系樹脂を含むことを特徴とする光学用フィルム：

[Wherein, n is 0 or 1, and m is 0 or an integer of 1 or more. X is independently a group represented by the formula: —CH═CH— or a group represented by the formula: —CH ₂ CH ₂ —, and R ¹ , R ² , R ³ and R ⁴ are each independently a hydrogen atom. A halogen atom; a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms which may have a linking group containing oxygen, nitrogen, sulfur or silicon; or a polar group, or R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ are bonded to each other to form a carbocyclic or heterocyclic ring (these carbocyclic or heterocyclic rings may have a monocyclic structure, or other rings may be condensed to form a polycyclic ring). A structure may be formed). The formed carbocyclic or heterocyclic ring may be an aromatic ring or a non-aromatic ring. ]
In which at least one of R ^{1 to} R ⁴ is a group represented by the following general formula (2) in at least a part of the structural unit a included in the polymer. Or at least one group selected from the following general formula (3) or (4), which is formed by bonding R ² and R ³ to each other, and has a photoelastic coefficient A thermoplastic norbornene-based resin having (C _P ) of 0 to 100 (× 10 ⁻¹² Pa ⁻¹ ) and a stress optical coefficient (C _R ) of 1500 to 4000 (× 10 ⁻¹² Pa ⁻¹ ) is included. Optical film characterized by:

— (CH ₂ ) _p —O—C (O) —R ⁵ (2)
[Wherein p is an integer of 1 to 5 and R ⁵ is a biphenylyl group, a naphthyl group (α or β), an anthracenyl group or a hydrogen atom of these groups is a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms. Represents a group substituted by. ]

［式中、Ｒ^１とＲ^４は上記一般式（１）に関して定義したとおりであり、Ｒ^６〜Ｒ^１１は各々独立に水素原子；ハロゲン原子；酸素、窒素、イオウ若しくはケイ素を含む連結基を有していてもよい置換又は非置換の炭素原子数１〜１０の１価炭化水素基；又は１価極性基を表す。］

[Wherein, R ¹ and R ⁴ are as defined in relation to the general formula (1), and R ^{6 to} R ¹¹ each independently represent a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur or silicon. A substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms which may have; or a monovalent polar group. ]

［式中、Ｒ^１とＲ^４は前記のとおりであり、Ｒ^１２〜Ｒ^１５は各々独立に水素原子；ハロゲン原子；酸素、窒素、イオウ若しくはケイ素を含む連結基を有していてもよい置換又は非置換の炭素原子数１〜１０の１価炭化水素基；又は１価極性基を表す。Ｖ及びＷは独立に単結合又は−Ｏ−、−ＣＯ−、−ＮＲ^１６−、−（ＣＲ^１７Ｒ^１８）_ｑ−（式中、ｑ＝１〜５）、−ＣＯＯ−及び−ＯＣＯ−からなる群から選ばれる２価の基を表わし、Ｒ^１６〜Ｒ^１８は各々独立にそれぞれ水素原子、ハロゲン原子、炭素数１〜１０の脂肪族炭化水素基、脂環族炭化水素基、又は芳香族炭化水素基を表わす。］
を提供する。

[Wherein, R ¹ and R ⁴ are as defined above, and R ^{12 to} R ¹⁵ each independently represent a hydrogen atom; a halogen atom; a substituent that may have a linking group containing oxygen, nitrogen, sulfur, or silicon. Or an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms; or a monovalent polar group. V and W are independently a single bond or —O—, —CO—, —NR ¹⁶ —, — (CR ¹⁷ R ¹⁸ ) _q — (wherein q = 1 to 5), —COO— and —OCO—. R ^{16 to} R ¹⁸ each independently represents a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group, or an aromatic group. Represents a hydrocarbon group. ]
I will provide a.

The present invention further provides the above optical film characterized in that it has a light diffusion function on at least one surface.
The present invention further provides the optical film described above, further comprising a transparent conductive layer on at least one surface.
The present invention further provides the optical film described above, further comprising an antireflection layer on at least one surface.
The present invention further provides a polarizing plate protective film comprising the above optical film.
The present invention further provides a polarizing plate comprising the optical film.

  The optical film of the present invention is characterized by high transparency, low retardation, and uniform and stable retardation when stretched and oriented, and heat resistance, other materials, which are the characteristics of conventional thermoplastic norbornene resin-based films It has good toughness and adhesiveness, small water absorption deformation, high toughness that could not be obtained with conventional thermoplastic norbornene resin film, and can control the phase difference of transmitted light during production it can. Therefore, this optical film is useful as a retardation film and as an optical film having functions such as a light diffusion function, transparent conductivity, and antireflection function.

[Optical film]
<Thermoplastic norbornene resin>
The polymer used for the optical film of the present invention, that is, the thermoplastic norbornene resin (hereinafter sometimes referred to as “resin of the present invention”) was selected from the following general formulas (2) to (4). The structural unit a having at least one group represented by the following general formula (1) is included as an essential structural unit (hereinafter referred to as “essential structural unit”), and further includes other structural units as necessary. It is optional.

［式中、ｎ，ｍ，Ｘ及びＲ¹〜Ｒ^４は、前記のとおりである。］

[Wherein, n, m, X and R ^{1 to} R ⁴ are as defined above. ]

— (CH ₂ ) _p —O—C (O) —R ⁵ (2)
[Wherein, p and R ⁵ are as defined above. ]

［式中、Ｒ^１，Ｒ^４及びＲ^６〜Ｒ^１１は、前記のとおりである。］

[Wherein, R ¹ , R ⁴ and R ^{6 to} R ¹¹ are as defined above. ]

［式中、Ｒ^１，Ｒ^４，Ｒ^１２〜Ｒ^１５，Ｖ及びＷは、前記のとおりである。］
ここで、一般式（１）〜（４）において、Ｒ^１〜Ｒ^４は、水素原子；ハロゲン原子；酸素、窒素、イオウ又はケイ素を含む連結基を有していてもよい置換又は非置換の炭素原子数１〜３０の炭化水素基；又は極性基を表すが、これらの原子及び基について説明する。

[Wherein R ¹ , R ⁴ , R ^{12 to} R ¹⁵ , V and W are as defined above. ]
Here, in the general formulas (1) to (4), R ^{1 to} R ^{4 each} represents a hydrogen atom; a halogen atom; a substituted or unsubstituted which may have a linking group containing oxygen, nitrogen, sulfur or silicon A hydrocarbon group having 1 to 30 carbon atoms; or a polar group, these atoms and groups will be described.

Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.
Examples of the hydrocarbon group having 1 to 30 carbon atoms include alkyl groups such as methyl group, ethyl group, and propyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; alkenyl groups such as vinyl group, allyl group, and propenyl group. Groups; aromatic groups such as phenyl, naphthyl, and anthracenyl groups; These hydrocarbon groups may be substituted, and examples of the substituent include halogen atoms such as fluorine, chlorine and bromine, phenylsulfonyl group and the like.

In addition, the above substituted or unsubstituted hydrocarbon group may be directly bonded to the ring structure, or may be bonded via a linkage. Examples of the linking group include a divalent hydrocarbon group having 1 to 10 carbon atoms (for example, an alkylene group represented by — (CH ₂ ) m — (wherein m is an integer of 1 to 10)); Linking groups containing oxygen, nitrogen, sulfur or silicon (for example, carbonyl group (—CO—), carbonyloxy group (—COO—), oxycarbonyl group (—OCO—), sulfone group (—SO ₂ —), ether Bond (—O—), thioether bond (—S—), imino group (—NH—), amide bond (—NHCO—, —CONH—), siloxane bond (—OSi (R ₂ ) — (where R May be an alkyl group such as methyl and ethyl)), and may be a linking group containing a plurality of these.

  Examples of the polar group include a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, an acyloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, a cyano group, an amide group, an imide ring-containing group, a triorganosiloxy group, and a triorganosilyl group. Group, amino group, acyl group, alkoxysilyl group, sulfonyl-containing group, carboxyl group and the like. More specifically, examples of the alkoxy group include a methoxy group and an ethoxy group; examples of the acyloxy group include an alkylcarbonyloxy group such as an acetoxy group and a propionyloxy group, and an arylcarbonyl such as a benzoyloxy group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group; examples of the aryloxycarbonyl group include a phenoxycarbonyl group, a naphthyloxycarbonyl group, a fluorenyloxycarbonyl group, and a biphenyl group. Examples of the triorganosiloxy group include trimethylsiloxy group and triethylsiloxy group; examples of the triorganosilyl group include trimethylsilyl group and triethylsilyl group. It can be mentioned; as the amino groups are exemplified primary amino group, alkoxysilyl The silyl groups such a trimethoxysilyl group, triethoxysilyl group, and the like.

  The polymer is at least one monomer selected from monomers represented by the following general formulas (5), (6) and (7) (hereinafter represented by the general formula (5)). The monomer is “specific monomer A”, the monomer represented by the general formula (6) is “specific monomer B”, the monomer represented by the general formula (7) is “specific monomer” It is obtained by polymerizing a monomer mixture containing “body C”).

［式中、Ｒ¹〜Ｒ^４は上記一般式（１）に関して定義したとおりである。ただし、Ｒ¹〜Ｒ^４のうち少なくとも１つは上記一般式（２）で表される基である。また、上記一般式（３）又は一般式（４）で表される構造の基を有しない。更に、ｈは０又は正の整数、ｉは０又は１である。ただし、ｈが０のときはｉも０である。］

[Wherein R ^{1 to} R ⁴ are as defined for the above general formula (1). However, at least one of R ^{1 to} R ⁴ is a group represented by the general formula (2). Moreover, it does not have the group of the structure represented by the said General formula (3) or General formula (4). Further, h is 0 or a positive integer, and i is 0 or 1. However, when h is 0, i is also 0. ]

［式中、Ｒ^１，Ｒ^４及びＲ^６〜Ｒ^１１は上記一般式（２）に関して定義したとおりである。また、ｊは０又は正の整数、ｋは０又は１である。ただし、ｊが０のときはｋも０である。］

[Wherein R ¹ , R ⁴ and R ^{6 to} R ¹¹ are as defined for the general formula (2). J is 0 or a positive integer, and k is 0 or 1. However, when j is 0, k is also 0. ]

［式中、Ｒ^１，Ｒ^４，Ｒ^１２〜Ｒ^１５、Ｖ及びＷは上記一般式（３）に関して定義したとおりである。ｓは０又は正の整数、ｔは０又は１である。ただし、ｓが０のときはｔも０である。］

[Wherein R ¹ , R ⁴ , R ^{12 to} R ¹⁵ , V and W are as defined for the general formula (3). s is 0 or a positive integer, and t is 0 or 1. However, when s is 0, t is also 0. ]

  Content of an essential structural unit is 100 to 5 weight% in the resin of this invention, Preferably it is 100 to 10 weight%, More preferably, it is 100 to 20 weight%. When the content of the essential structural unit is 5% by weight or less, stretching orientation for obtaining an optical film that gives transmitted light having a desired retardation may be difficult.

  The resin of the present invention can contain structural units other than the essential structural units. Examples of such a structural unit include the structural unit a represented by the general formula (1) and excluding the essential structural unit. Such a structural unit a is a monomer represented by the following general formula (8) (hereinafter referred to as “specific monomer D”) at least one selected from the specific monomers A, B, and C. Obtained by copolymerizing with seeds.

［式中、ｈ、ｉ、Ｒ¹、Ｒ^２、Ｒ^３及びＲ^４は一般式（１）及び（５）に関して定義のとおりである。ただし、一般式（５）〜（７）で表される単量体を除く。］

[Wherein h, i, R ¹ , R ² , R ³ and R ⁴ are as defined for the general formulas (1) and (5). However, the monomers represented by the general formulas (5) to (7) are excluded. ]

More specific examples of the resin of the present invention include polymers shown in the following (1) to (4).
(1) A ring-opening polymer of at least one monomer selected from the specific monomers A, B and C.
(2) A ring-opening copolymer of at least one monomer selected from the specific monomers A, B and C and the specific monomer D.
(3) Ring-opening copolymer of at least one monomer selected from specific monomers A, B and C and a copolymerizable monomer excluding specific monomer D, or a specific monomer A ring-opening copolymer of at least one monomer selected from the bodies A, B and C and a specific monomer D and a copolymerizable monomer excluding the specific monomer D.
(4) Hydrogenated product of the ring-opening polymer or ring-opening copolymer of (1), (2) and (3).

  The specific monomer A, the specific monomer B, the specific monomer C, and the specific monomer D will be described more specifically, but are not limited to the following.

<Specific monomer A>
5- (4-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (4-biphenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene,
5- (4-biphenylcarbonyloxypropyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5- (4-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (2-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (2-biphenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5- (2-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (3-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (3-biphenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene,
5- (1-naphthylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (1-naphthylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5- (1-naphthylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (2-naphthylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (2-naphthylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5- (2-naphthylcarbonyloxymethyl) methylbicyclo [2.2.1] hept-2-ene,
5- (9-anthracenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
5- (9-anthracenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5- (9-anthracenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene,
8- (4-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (4-biphenylcarbonyloxyethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (4-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (2-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (2-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (3-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (3-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (1-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (1-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (2-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (2-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (9-anthracenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (9-anthracenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . ^{17, 10} ] -3-dodecene and the like. You may use these in combination of 2 or more type.

<Specific monomer B>
1,2- (2H, 3H- [1,3] epicyclopenta) -1,2-dihydroacenaphthylene represented by the following formula (a):

下記式（ｂ）で表される、１，２−（２H、３H−［１，３］エピシクロペンタ）−１、２−ジヒドロアセナフチレンとシクロペンタジエンのディールス・アルダー付加体、

Diels-Alder adduct of 1,2- (2H, 3H- [1,3] epicyclopenta) -1,2-dihydroacenaphthylene and cyclopentadiene represented by the following formula (b):

又は、これらの芳香環の水素原子がハロゲン原子、炭素数１〜１０の炭化水素基で置換された置換体などを挙げることができる。これらは２種以上を組み合わせて使用してもよい。

Or the substituent etc. by which the hydrogen atom of these aromatic rings was substituted by the halogen atom and the C1-C10 hydrocarbon group can be mentioned. You may use these in combination of 2 or more type.

<Specific monomer C>
1,4-methano-1,4,4a, 9a-tetrahydrofluorene,
1,4-methano-1,4,4a, 9,9a, 10-hexahydroanthracene,
1,4-methano-1,4,4a, 9,10,10a-hexahydrophenanthrene,
11,12-benzo-pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] -4-pentadecene,
11,12-benzo-pentacyclo [6.6.1.1 ^3,6 . 0 ^2,7 . 0 ^9,14 ] -4-hexadecene,
1,4-methano-1,4,4a, 9a-tetrahydrodibenzofuran,
1,4-methano-1,4,4a, 9a-tetrahydrocarbazole,
1,4-methano-1,4,4a, 10a-tetrahydroanthraquinone,
Etc. You may use these in combination of 2 or more type.

<Specific monomer D>
Bicyclo [2.2.1] hept-2-ene,
5-methylbicyclo [2.2.1] hept-2-ene,
5-ethylbicyclo [2.2.1] hept-2-ene,
5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-cyanobicyclo [2.2.1] hept-2-ene,
5-ethylidenebicyclo [2.2.1] hept-2-ene,
8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
5-phenylbicyclo [2.2.1] hept-2-ene,
5- (2-naphthyl) bicyclo [2.2.1] hept-2-ene (both α and β types are acceptable),
5-fluorobicyclo [2.2.1] hept-2-ene,
5-fluoromethylbicyclo [2.2.1] hept-2-ene,
5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-pentafluoroethylbicyclo [2.2.1] hept-2-ene,
5,5-difluorobicyclo [2.2.1] hept-2-ene,
5,6-difluorobicyclo [2.2.1] hept-2-ene,
5,5-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5,5,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,5,6-tris (fluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrafluorobicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrakis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5-difluoro-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-fluoro-5-pentafluoroethyl-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5-heptafluoro-iso-propyl-6-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-chloro-5,6,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,6-dichloro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-trifluoromethoxybicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-heptafluoropropoxybicyclo [2.2.1] hept-2-ene,
4- (bicyclo [2.2.1] hept-5-en-2-yl) phenylsulfonylbenzene 1,2- (2H, 3H- [1,3] epicyclopenta) -1,2-dihydroacenaphthy Lentricyclo [5.2.1.0 ^2,6 ] -8-decene,
Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
Pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] -4-pentadecene,
Pentacyclo [7.4.0.1 ^2,5 . 1 ^9,12 . 0 ^8,13 ] -3-pentadecene,
Tricyclo [4.4.0.1 ^2,5 ] -3-undecene,
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-phenoxycarbonyltetracyclo [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-methyl-8-phenoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
Pentacyclo [8.4.0.1 ^2,5 . 1 ^9,12 . 0 ^8,13 ] -3-hexadecene,
Heptacyclo [8.7.0.1 ^3,6 . 1 ^10,17 . 1 ^12,15 . 0 ^2,7 . 0 ^11,16 ] -4-Eicosen,
Heptacyclo [8.8.0.1 ^4,7 . 1 ^11,18 . 1 ^13,16 . 0 ^3,8 . 0 ^12,17 ] -5- ^Haneikosen ,
8-ethylidenetetracyclo [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-methyl-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-difluoromethyltetracyclo [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-pentafluoroethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8-difluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
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-methyl-8-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-trifluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-tris (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9,9-tetrafluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9,9-tetrakis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
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-trifluoromethyltetracyclo [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-heptafluoroiso-propyl-9-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-chloro-8,9,9-trifluorotetracyclo [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-trifluoroethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene.

One or more of these may be used in combination with at least one monomer selected from the specific monomer A, the specific monomer B, and the specific monomer C.
Among these, in the general formula (8), the specific monomer D in which h = 1 and i = 0 is preferable from the viewpoint of the balance between heat resistance and toughness of the obtained polymer. That is, when a specific monomer D having h of 2 or more or i of 1 or more is used, the glass transition temperature (Tg) of the resulting polymer tends to increase and heat resistance tends to be improved. There is a tendency that toughness is lowered, and when it is made into a film, there may be a problem that it is easily cracked or broken during processing or use.
Further, it is preferable to use a specific monomer D having at least one polar group in the molecule. That is, in the general formula (8), any ^one of R ^{1 to} R ⁴ is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and the remaining one is a polar group other than a hydrocarbon group. However, this is preferable because it improves adhesion and adhesion to other materials.

Further, the polar group has the general formula (9):
^{_{- (CH 2) z COOR 19}} (9)
[Wherein z is usually 0 to 5, preferably 0 to 2, and more preferably 0. R ¹⁹ is a monovalent organic group. ]
The specific monomer D which is a polar group represented by the formula is preferred in that the glass transition temperature and water absorption of the resulting polymer can be easily controlled. Examples of the monovalent organic group represented by R ¹⁹ in the general formula (9) include alkyl groups such as a methyl group, an ethyl group, and a propyl group; and aryl groups such as a phenyl group, a naphthyl group, an anthracenyl group, and a biphenylyl group. Other examples include monovalent groups having an aromatic ring such as fluorenes such as diphenylsulfone and tetrahydrofluorene, and a heterocyclic ring such as a furan ring and an imide ring. Further, in the general formula (9), z is usually 0 to 5 as described above, but the smaller the value of z, the higher the glass transition temperature of the polymer obtained, which is preferable. In particular, z is 0. The specific monomer D is preferable because it can be easily synthesized.

Furthermore, in the above general formula (8), the fact that the alkyl group is bonded to the carbon atom bonded to the polar group represented by the general formula (9) balances the heat resistance and water absorption of the resulting polymer. It is preferable to plan. The alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 2, and particularly preferably 1.
Specific examples of the specific monomer D mentioned above include 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1, ¹⁰ ] -3-dodecene is preferable because it increases the glass transition temperature, hardly receives adverse effects such as deformation due to water absorption, and can maintain water absorption to such an extent that adhesion and adhesion to other materials are good. .

The content of the polar group in the polymer is determined according to the desired function and the like and is not particularly limited. However, the structural unit a having a polar group in all the structural units is usually 1 mol% or more, preferably 5 mol% or more, more preferably 10 mol% or more is contained. All the structural units may have a polar group.
Introduction of the polar group into the structural unit a may be carried out by copolymerizing the specific monomer D having the polar group, or at least one of R ^{1 to} R ⁴ in the general formula (5) is a polar group. A specific monomer A, a specific monomer B or a specific monomer C in which at least one of R ¹ or R ^{4 in} the general formula (6) or general formula (7) is a polar group are copolymerized. Also good.

<Other copolymerizable monomers>
Copolymerizing with at least one monomer selected from the specific monomer A, the specific monomer B and the specific monomer C, or with the specific monomer D used as necessary. Examples of other copolymerizable monomers that can be used include cycloolefins such as cyclobutene, cyclopentene, cycloheptene, cyclooctene, tricyclo [5.2.1.0 ^2,6 ] -3-decene, and dicyclopentadiene. Can be mentioned. The number of carbon atoms in the cycloolefin is preferably 4-20, and more preferably 5-12.
In addition, in the presence of unsaturated hydrocarbon polymers with olefinically unsaturated bonds in the main chain, such as polybutadiene, polyisoprene, styrene-butadiene copolymer, ethylene-nonconjugated diene copolymer, polynorbornene, etc. At least one monomer selected from the monomer A, the specific monomer B, and the specific monomer C may be polymerized. At this time, the specific monomer D or another copolymerizable monomer may be polymerized as necessary. The polymer obtained in this case is useful as a raw material for resins having excellent impact resistance.

<Polymerization conditions>
At least one monomer selected from the specific monomer A, the specific monomer B, and the specific monomer C, and the specific monomer D or other copolymerizable monomer used as necessary Other conditions for the ring-opening polymerization reaction of the body will be described.
·catalyst:
The ring-opening polymerization reaction is performed in the presence of a metathesis catalyst.
This metathesis catalyst comprises (a) at least one selected from W, Mo and Re compounds, (b) Deming periodic table group IA elements (for example, Li, Na, K, etc.), IIA group elements (for example, Mg, Ca, etc.), group IIB elements (eg, Zn, Cd, Hg, etc.), group IIIB elements (eg, B, Al, etc.), group IVA elements (eg, Ti, Zr, etc.) or group IVB elements (eg, Si, Sn, etc.) Pb or the like), and a catalyst comprising a combination with at least one selected from those having at least one element-carbon bond or element-hydrogen bond. In this case, an additive (c) described later may be added to increase the activity of the catalyst.

Representative examples of W, Mo or Re compounds suitable as the component (a) include compounds described in JP-A-1-240517 such as WCl ₆ , MoCl ₅ and ReOCl ₃ .
(B) Specific examples of the _{component, 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, (C 2 H ₅ ) The compounds described in JP-A-1-240517 such as AlCl ₂ , methylalumoxane, LiH and the like can be mentioned.
As typical examples of the component (c), alcohols, aldehydes, ketones, amines and the like can be preferably used, and compounds described in JP-A-1-240517 can be further used.

The amount of the metathesis catalyst used is a mole of the component (a) and the specific monomers A to D (hereinafter, the specific monomers A to D are simply referred to as “specific monomers”). The ratio of component (a): specific monomer is usually 1: 500 to 1: 50000, preferably 1: 1000 to 1: 10000.
The ratio of the component (a) to the component (b) is such that the metal atomic ratio of “(a) :( b)” is in the range of 1: 1 to 1:50, preferably 1: 2 to 1:30. .
The ratio of the component (a) to the component (c) is such that the molar ratio “(c) :( a)” is 0.005: 1 to 15: 1, preferably 0.05: 1 to 7: 1. It is said.

・ Molecular weight regulator:
Although the molecular weight of the polymer can be adjusted depending on the polymerization temperature, the type of catalyst, and the type of solvent, in the present invention, it is preferable to adjust by allowing a molecular weight regulator to coexist in the reaction system.
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. Of these, 1-butene and 1-hexene are preferred.
These molecular weight regulators can be used alone or in admixture of two or more.
The amount of the molecular weight regulator used is 0.005 to 0.6 mol, preferably 0.02 to 0.5 mol, per 1 mol of the specific monomer subjected to the polymerization reaction.

・ Solvent for ring-opening polymerization reaction:
Examples of the solvent used in the polymerization reaction include alkanes such as pentane, hexane, heptane, octane, nonane, and decane; cycloalkanes such as cyclohexane, cycloheptane, cyclooctane, decalin, and norbornane; benzene, toluene, xylene, and ethylbenzene. , Aromatic hydrocarbons such as cumene; halogenated alkanes such as chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylene dibromide, chlorobenzene, chloroform, tetrachloroethylene; compounds such as aryl; ethyl acetate, n-butyl acetate, iso -Saturated carboxylic acid esters such as butyl, methyl propionate and dimethoxyethane; and ethers such as dibutyl ether, tetrahydrofuran and dimethoxyethane. Can be, it may be used in combination either alone or in combination of two or more. Among these, the above aromatic hydrocarbons are preferable.
The amount of the solvent used is such that the solvent: specific monomer (weight ratio) is usually 1: 1 to 10: 1, and preferably 1: 1 to 5: 1.

-Hydrogenation of polymer:
The polymer obtained as described above can be used as the resin of the present invention as it is, but it is preferable to use the residual olefinically unsaturated bond after hydrogenation.
In the hydrogenation reaction, a hydrogenation catalyst is added to the polymer solution in the usual manner, and hydrogen gas at normal pressure to 300 atm, preferably 3 to 200 atm, is added thereto at 0 to 200 ° C., preferably 20 to 20 ° C. It is performed by operating at 180 ° C.

As a hydrogenation catalyst, what is used for the hydrogenation reaction of a normal olefinic compound can be used. As this hydrogenation catalyst, a heterogeneous catalyst and a homogeneous catalyst are known.
Examples of the heterogeneous catalyst include solid catalysts in which noble metals such as palladium, platinum, nickel, rhodium, and ruthenium are supported on a carrier such as carbon, silica, alumina, and titania. The homogeneous catalysts include nickel naphthenate / triethylaluminum, nickel acetylacetonate / triethylaluminum, cobalt octenoate / n-butyllithium, titanocene dichloride / diethylaluminum monochloride, rhodium acetate, chlorotris (triphenylphosphine) rhodium. Dichlorotris (triphenylphosphine) ruthenium, chlorohydrocarbonyltris (triphenylphosphine) ruthenium, dichlorocarbonyltris (triphenylphosphine) ruthenium, and the like. The form of the catalyst may be powder or granular.
These hydrogenation catalysts are used in such a ratio that the polymer: hydrogenation catalyst (weight ratio) is 1: 1 × 10 ⁻⁶ to 1: 2.

  The hydrogenated polymer obtained by hydrogenation has excellent thermal stability, and its characteristics are not easily deteriorated by heating during film formation, during stretching or during use as a product. The hydrogenation rate of the olefinically unsaturated bond is usually 50% or more, preferably 70% or more, more preferably 90% or more, and particularly preferably 98% or more.

  In addition, the aromatic ring in the structural unit a derived from the specific monomer A, the specific monomer B, or the specific monomer C needs to be substantially not hydrogenated even by the hydrogenation reaction. Such a hydrogenation reaction can be carried out by using the above-mentioned conditions for the hydrogenation reaction of the normal olefinic compound, but the hydrogen gas pressure and reaction temperature are set lower in the above ranges, or the hydrogenation catalyst is used. It may be necessary to adjust conditions such as adjusting the type and amount of addition. In addition, when the specific monomer D or other copolymerizable monomer has a substituent containing an aromatic ring and the structural unit derived from the monomer contains an aromatic ring, the aromatic ring may be unaffected by hydrogenation. It is desirable to select conditions under which saturated bonds are not substantially hydrogenated.

<Characteristics of thermoplastic norbornene resin>
The intrinsic viscosity (η _inh ) of the resin of the present invention measured in chloroform at 30 ° C. is preferably 0.2 to 5 dl / g. More preferably, it is 0.3-4 dl / g, Most preferably, it is 0.5-3 dl / g. If it exceeds 5 dl / g, the solution viscosity becomes too high and the processability deteriorates, which is not preferred, and if it is less than 0.2 dl / g, the film strength decreases.
As for the molecular weight of the resin of the present invention, the polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is usually 8,000 to 1,000,000, preferably 10,000 to 500. 000, more preferably 20,000 to 100,000, particularly preferably 30,000 to 100,000, and the weight average molecular weight (Mw) is usually 20,000 to 3,000,000, preferably 30 , 1,000 to 1,000,000, more preferably 40,000 to 500,000, particularly preferably 40,000 to 300,000. When Mw and Mn are larger than the above ranges, the solution viscosity becomes too high and processability may be deteriorated. When smaller than the above ranges, the strength of the film may be lowered.
The molecular weight distribution is such that the above Mw / Mn is usually 1.5 to 10, preferably 2 to 8, more preferably 2.5 to 5, particularly preferably 2.5 to 4.5. When Mw / Mn is larger than the above range, the amount of low molecular weight components becomes excessive, and when a film is produced, the low molecular weight components on the surface of the film may bleed and stickiness may occur. On the other hand, when it is smaller than the above range, the strength, particularly toughness, of the film may be lowered.

  The glass transition temperature (Tg) of the resin of the present invention is usually 80 to 350 ° C., preferably 100 to 250 ° C. When Tg is less than 80 ° C., the heat distortion temperature is lowered, which may cause a problem in the heat resistance of the resulting film. On the other hand, when Tg is 350 ° C. or higher, the processing temperature when processing the obtained film by heating such as stretching may become too high, which may cause a problem that the film is thermally deteriorated.

The saturated water absorption at 23 ° C. of the resin of the present invention is usually 0.05 to 1% by weight, preferably 0.1 to 0.7% by weight, and more preferably 0.1 to 0.5% by weight. If the saturated water absorption is within this range, various optical properties such as transparency, retardation and retardation uniformity or dimension accuracy are maintained even under conditions such as high temperature and humidity, and adhesion to other materials. In addition, since it is excellent in adhesiveness, peeling does not occur during use, and since compatibility with additives such as antioxidants is good, the degree of freedom of addition is increased.
When the saturated water absorption is less than 0.05% by weight, adhesion and adhesion to other materials are poor, and peeling tends to occur during use. In addition, there are limitations on the blending of additives such as antioxidants. On the other hand, if it exceeds 1% by weight, the optical characteristics and dimensional changes are likely to occur due to water absorption.
In addition, said saturated water absorption is the value calculated | required by immersing in 23 degreeC water for 1 week, and measuring an increase weight based on ASTMD570.

The SP value (solubility parameter) of the resin of the present invention is preferably 10 to 30 (MPa ^1/2 ), more preferably 12 to 25 (MPa ^1/2 ), and particularly preferably 15 to 20 (MPa ^1/2 ). It is. By making the SP value within this range, it can be dissolved well in general general-purpose solvents and can be manufactured stably at the time of film production. Therefore, it is possible to control an appropriate water absorption rate.

<Photoelastic coefficient (C _P ) / stress optical coefficient (C _R )>
The thermoplastic norbornene-based resin used for the optical film of the present invention has a photoelastic coefficient (C _P ) of 0 to 100 (× 10 ⁻¹² Pa ⁻¹ ) and a stress optical coefficient (C _R ) of 1500 to 1500. 4000 (× 10 ⁻¹² Pa ⁻¹ ).

Here, the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) will be described. These coefficients are based on various documents (Polymer Journal: Vol.27, No.9, pp 943-950 (1995), “Journal of the Japanese Society of Rheology”: Vol.19, No.2, pp 93-97 (1991). , "Photoelastic experiment method": Nikkan Kogyo Shimbun, 7th edition of Showa 50), the meaning of the former is to provide phase difference to transmitted light due to stress in the glassy state of the polymer The latter indicates the degree of phase difference imparted to the transmitted light due to the stress in the flow state.

That is, when the photoelastic coefficient (C _P ) is large, the phase difference of transmitted light changes sensitively due to external stress or internal stress caused by its own freezing strain when the polymer is used in a glass state. This means that, for example, when the optical film is bonded to a polarizing plate or glass plate, residual strain at the time of bonding, or due to minute stress generated by material shrinkage due to temperature change or humidity change, etc. This means that the phase difference of transmitted light is likely to change.
On the other hand, when the stress optical coefficient (C _R ) is large, it becomes possible to give a desired retardation imparting function with a small stretch ratio when imparting a retardation imparting function to transmitted light to an optical film, It is easy to obtain a film that gives a high retardation to transmitted light, and when the same retardation is desired, the film can be made thinner than a film having a small stress optical coefficient (C _R ).

From the above viewpoint, the photoelastic coefficient (C _P ) is 0 to 100 (× 10 ⁻¹² Pa ⁻¹ ), preferably 0 to 80 (× 10 ⁻¹² Pa ⁻¹ ), and more preferably 0 to 50 ( × 10 ⁻¹² Pa ⁻¹ ), particularly preferably 0 to 30 (× 10 ⁻¹² Pa ⁻¹ ), most preferably 0 to 20 (× 10 ⁻¹² Pa ⁻¹ ), and the stress optical coefficient (C _R ) is 1500 to 4000 (× 10 ⁻¹² Pa ⁻¹ ), preferably 1700 to 4000 (× 10 ⁻¹² Pa ⁻¹ ), more preferably 1900 to 4000 (× 10 ⁻¹² Pa ⁻¹ ), particularly preferably. A thermoplastic norbornene-based resin of 2100 to 4000 (× 10 ⁻¹² Pa ⁻¹ ), most preferably 2300 to 4000 (× 10 ⁻¹² Pa ⁻¹ ) is included in the optical film of the present invention. It is necessary to

That is, when the photoelastic coefficient exceeds 100 (× 10 ⁻¹² Pa ⁻¹ ), when the optical film is used after being bonded to a polarizing plate, glass, or the like, the phase difference of transmitted light is changed due to environmental changes or the like. It is not preferable because it may change and cause color unevenness.
On the other hand, when the stress optical coefficient (C _R ) is less than 1500 (× 10 ⁻¹² Pa ⁻¹ ), the function of giving a phase difference to transmitted light obtained by stretching orientation may be limited, and 4000 ( If it exceeds × 10 ⁻¹² Pa ⁻¹ ), the retardation of the light transmitted through the stretched and oriented optical film tends to cause unevenness in the surface, which is not preferable.

<Additives>
The resin of the present invention may be blended with known thermoplastic resins, thermoplastic elastomers, rubber polymers, organic fine particles, inorganic fine particles and the like as long as transparency and heat resistance are not impaired.
Moreover, you may add additives, such as antioxidant, to the resin of this invention, As such additives, such as antioxidant, the following compounds are mentioned, for example.
·Antioxidant:
2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3,3′-di-t-butyl-5,5′-dimethyldiphenylmethane, tetrakis [methylene-3- (3 5-Di-tert-butyl-4-hydroxyphenyl) propionate] methane, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl- 2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,2 '-Dioxy-3,3'-di-t-butyl-5,5'-diethylphenylmethane, 3,9-bis [1,1-dimethyl-2- (β- (3-t-butyl-4- Hydroxy-5-methylphenyl) propio Nyloxy) ethyl], 2,4,8,10-tetraoxospiro [5.5] undecane, tris (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,4 -Di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,6-di-t-butyl-4-methylphenyl) phosphite, 2,2-methylenebis (4,6-di-t -Butylphenyl) octyl phosphite;
・ UV absorber:
2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone The addition amount of these antioxidants and the like is usually 0.01 to 3 parts by weight, preferably 100 parts by weight of the thermoplastic norbornene resin. 0.05 to 2 parts by weight.
Furthermore, additives such as a lubricant can be added for the purpose of improving processability.

<Film forming method>
The optical film of the present invention can be formed into a film or a sheet of the resin of the present invention by a melt molding method or a solution casting method (solvent casting method). Among these, the solvent casting method is preferable from the viewpoint of good film thickness uniformity and surface smoothness.
Examples of the solvent casting method include a method in which the resin of the present invention is dissolved or dispersed in a solvent to obtain a liquid having an appropriate concentration, poured or applied onto a suitable carrier, dried, and then peeled off from the carrier. It is done.

When the thermoplastic norbornene resin is dissolved or dispersed in a solvent, the concentration of the resin is usually 0.1 to 90% by weight, preferably 1 to 50% by weight, more preferably 10 to 35% by weight. . When the concentration of the resin is less than the above, it becomes difficult to secure the thickness of the film, and problems such as difficulty in obtaining the surface smoothness of the film due to foaming due to solvent evaporation and the like occur. On the other hand, a concentration exceeding the above is not preferable because the viscosity and the surface of the optical film obtained due to the solution viscosity becoming too high become difficult to be uniform.
The viscosity of the solution at room temperature is usually 1 to 1,000,000 (mPa · s), preferably 10 to 100,000 (mPa · s), more preferably 100 to 50,000 (mPa · s). s), particularly preferably 1,000 to 40,000 (mPa · s).

  Solvents used include aromatic solvents such as benzene, toluene, xylene, cellosolve solvents such as methyl cellosolve, ethyl cellosolve, 1-methoxy-2-propanol, diacetone alcohol, acetone, cyclohexanone, methyl ethyl ketone, 4-methyl. -2-pentanone, cyclohexanone, ethylcyclohexanone, ketone solvents such as 1,2-dimethylcyclohexane, ester solvents such as methyl lactate and ethyl lactate, 2,2,3,3-tetrafluoro-1-propanol, methylene chloride And halogen-containing solvents such as chloroform, ether solvents such as tetrahydrofuran and dioxane, and alcohol solvents such as 1-pentanol and 1-butanol.

In addition to the above, the SP value (solubility parameter) is usually 10 to 30 (MPa ^1/2 ), preferably 10 to 25 (MPa ^1/2 ), more preferably 15 to 25 (MPa ^1/2 ), particularly When a solvent in the range of preferably 15 to 20 (MPa ^1/2 ) is used, an optical film having good surface uniformity and optical properties can be obtained.
The said solvent can be used individually or in combination of 2 or more types. When using 2 or more types of solvent together, it is preferable to make the range of SP value as a mixture into the said range. At this time, the value of the SP value as a mixture can be determined from the weight ratio. For example, in the case of two kinds of mixtures, the weight fraction of each solvent is W1, W2, and the SP value is SP1, SP2. Then, the SP value of the mixed solvent is expressed by the following formula:
SP value = W1 · SP1 + W2 · SP2
It can obtain | require as a value calculated by.

  When the above mixed solvent is used, an optical film having a light diffusion function can be obtained by combining a good solvent and a poor solvent of the resin of the present invention. Specifically, SP values of resin, good solvent and poor solvent are [SP value: resin], [SP value: good solvent] and [SP value: poor solvent], respectively, [SP value: resin] and [SP. Value: good solvent] is preferably 7 or less, more preferably 5 or less, particularly preferably 3 or less, and the difference between [SP value: resin] and [SP value: poor solvent] is preferably 7 or more, more preferably 8 or more, particularly preferably 9 or more, and the difference between [SP: good solvent] and [SP: poor solvent] is preferably 3 or more, more preferably 5 or more, more preferably 7 or more. By doing, a light-diffusion function can be provided to the optical film obtained.

The proportion of the poor solvent in the mixed solvent is preferably 50% by weight or less, more preferably 30% by weight or less, particularly preferably 15% by weight or less, and most preferably 10% by weight or less. The difference between the boiling point of the poor solvent and the boiling point of the good solvent is preferably 1 ° C. or higher, more preferably 5 ° C. or higher, particularly preferably 10 ° C. or higher, and most preferably 20 ° C. or higher. It is preferably higher than the boiling point of the solvent.
The temperature for dissolving the thermoplastic norbornene resin with a solvent may be room temperature or high temperature. A uniform solution can be obtained by thorough stirring. In addition, when coloring as needed, coloring agents, such as dye and a pigment, can also be suitably added to a solution.
Further, a leveling agent may be added to improve the surface smoothness of the optical film. Any general leveling agent can be used. For example, a fluorine-based nonionic surfactant, a special acrylic resin leveling agent, a silicone leveling agent, and the like can be used.

  As a method for producing the optical film of the present invention by a solvent casting method, the solution is a metal film using a die or a coater, a steel belt, a polyester film such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), In general, a method of coating on a substrate such as a polytetrafluoroethylene belt, and then drying and removing the solvent to peel off the film from the substrate. Alternatively, the resin solution can be applied to the substrate using means such as spraying, brushing, roll spin coating, dipping, etc., and then the solvent is dried and removed to peel the film from the substrate. The thickness and surface smoothness may be controlled by repeating the coating.

  Moreover, when using a polyester film as a base material, you may use the film by which surface treatment was carried out. As a surface treatment method, a hydrophilic treatment method generally performed, for example, a method of laminating an acrylic resin or a sulfonate group-containing resin by coating or lamination, or a hydrophilic property of the film surface by corona discharge treatment or the like. The method etc. which improve are mentioned.

In addition, when using a substrate to which the above solution is applied, such as a metal drum, a steel belt, a polyester film, etc., which has been subjected to sand mat treatment or emboss treatment, unevenness due to the treatment is transferred to the surface of the film, The optical film having the light diffusion function of the present invention can be produced.
When the light diffusing function is imparted as described above, it is preferable to form irregularities with a certain size from the viewpoint of stably maintaining the light transmittance from a low wavelength to a high wavelength. The shape of the unevenness at this time is not particularly limited because it depends on the method of forming the unevenness, but usually the surface roughness (centerline average roughness: Ra) is 0.001 to 100 μm, preferably 0. 0.005 to 10 μm, more preferably 0.01 to 1 μm, and particularly preferably 0.05 to 1 μm. When the value of Ra is less than 0.001 μm or exceeds 100 μm, it is difficult to expect a good light diffusion function. In addition, when providing a lens function like a Fresnel lens, the value of Ra may exceed 100 micrometers.
Furthermore, the optical film having the light diffusing function of the present invention can also be produced by a method of casting a uniform solution obtained by adding a resin or filler incompatible with the resin of the present invention.

  Specifically, when the incompatible resin is added, the refractive index difference from the resin of the present invention is usually 0.00001 or more, preferably 0.0001 or more, more preferably 0.001 or more, Particularly preferably, a resin of 0.01 or more is selected and used, and the number average particle size range of the incompatible resin in the film obtained after being mixed with the solution, cast and dried is usually Is 0.01 to 1000 μm, preferably 0.05 to 500 μm, more preferably 0.1 to 100 μm, and particularly preferably 0.5 to 50 μm, thereby exhibiting a light diffusion effect from low to high wavelengths. can do. When the refractive index difference is less than 0.00001 or the particle diameter is less than 0.01 μm, it is difficult to provide a good light diffusion function, while the particle diameter exceeds 1000 μm. In some cases, the light transmittance is remarkably lowered, and the thickness accuracy and surface properties of the film may be adversely affected.

  The amount of the incompatible resin to be added varies depending on the required light diffusion performance, but is usually 0.001 to 100 parts by weight, preferably 0.01 to 100 parts by weight of the resin of the present invention. It is -70 weight part, More preferably, it is 0.1-50 weight part, Most preferably, it is 1-25 weight part. When the addition amount is less than 0.001 part by weight, it is difficult to expect a good light diffusion function. Moreover, since the light transmittance will fall remarkably when the addition amount will be 100 weight part or more, it is not preferable.

On the other hand, as the filler, a commercially available inorganic filler, an organic filler obtained by miniaturizing a cured product of a thermosetting resin, or the like can be arbitrarily used. Moreover, the particle diameter and addition amount are the same as the case where the said incompatible resin is added.
Examples of the resin incompatible with the resin of the present invention include polymethyl methacrylate (PMMA), polystyrene, polyvinylbenzene, polyamide, and polyimide. Further, as the filler, for example, gold, metals such as _{silver, SiO 2, TiO 2, ZnO} 2, Al metal oxides such as 2 _{O 3,} glass, particles such as quartz.

The drying (solvent removal) step of the solvent casting method is not particularly limited and can be carried out by a generally used method, for example, a method of passing through a drying furnace through a large number of rollers. If bubbles are generated as a result of evaporation, the characteristics of the film are remarkably deteriorated. Therefore, in order to avoid this, it is preferable to control the temperature or air volume in each step by making the drying step into a plurality of steps of two or more steps.
The residual solvent amount in the optical film is usually 10% by weight or less, preferably 5% by weight or less, more preferably 1% by weight or less, and particularly preferably 0.5% by weight or less. Here, when the residual solvent amount is 10% by weight or more, the dimensional change with time becomes large when the optical film is actually used, which is not preferable. Further, the residual solvent is not preferable because Tg is lowered and heat resistance is also lowered.

  In addition, in order to perform the extending | stretching process mentioned later suitably, it is necessary to adjust the said residual solvent amount suitably within the said range. Specifically, in order to stably and evenly express the phase difference during stretching orientation, the residual solvent amount is usually 10 to 0.1% by weight, preferably 5 to 0.1% by weight, more preferably 1 May be -0.1 wt%. By leaving a trace amount of the solvent, stretching may be facilitated or phase difference may be easily controlled.

The thickness of the optical film of the present invention is usually 0.1 to 3,000 μm, preferably 0.1 to 1,000 μm, more preferably 1 to 500 μm, and most preferably 5 to 300 μm. When the thickness is less than 0.1 μm, handling becomes substantially difficult. On the other hand, in the case of 3,000 μm or more, it is difficult to wind in a roll shape.
The thickness distribution of the optical film of the present invention is usually within ± 20% of the average value, preferably within ± 10%, more preferably within ± 5%, and particularly preferably within ± 3%. The thickness variation per cm is usually 10% or less, preferably 5% or less, more preferably 1% or less, and particularly preferably 0.5% or less. By carrying out such thickness control, it is possible to prevent retardation unevenness when stretched and oriented.

<Optical film to give phase difference to transmitted light>
The present invention provides an optical film that gives a retardation to transmitted light (hereinafter referred to as “retardation film”). In the retardation film, since the polymer chains of the thermoplastic norbornene resin as a material are oriented in a certain direction, a retardation can be given to transmitted light. The retardation film can be obtained by regularly orienting the polymer chain by subjecting the optical film of the present invention to processing such as stretching. Here, the regular orientation depends on the magnitude of distortion of the film generated in the process when a normal polymer is formed into a film by a melt extrusion method or a casting method described later. However, the molecular chain is in a random state with no specific direction, whereas in this retardation film as a whole, the molecular chain is regularly oriented in the uniaxial direction or biaxial direction of the film plane and further in the thickness direction. Means. The degree of regularity of orientation varies.

Specific examples of the stretching method for producing the retardation film of the present invention include a known uniaxial stretching method or biaxial stretching method. That is, by the horizontal uniaxial stretching method by the tenter method, the compression stretching method between rolls, the longitudinal uniaxial stretching method using two sets of rolls with different circumferences, or the biaxial stretching method combining the horizontal uniaxial and the longitudinal uniaxial, the inflation method A stretching method or the like can be used.
In the case of the uniaxial stretching method, the stretching speed is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably 100 to 1,000% / min, Preferably, it is 100 to 500% / min.
In the case of the biaxial stretching method, stretching may be performed in two directions at the same time, or the stretching may be performed in a direction different from the first stretching direction after uniaxial stretching. At this time, the intersecting angle of the two stretching axes for controlling the shape of the refractive index ellipsoid of the film after stretching is not particularly limited because it is determined by desired characteristics, but is usually in the range of 120 to 60 degrees. It is. The stretching speed may be the same or different in each stretching direction, and is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably Is from 100 to 1,000% / min, particularly preferably from 100 to 500% / min.

  The stretching temperature is not particularly limited, but is usually Tg ± 30 ° C., preferably Tg ± 15 ° C., more preferably Tg−5 ° C., based on the glass transition temperature Tg of the resin used in the present invention. It is the range of -Tg + 15 degreeC. Within the above range, it is possible to suppress the occurrence of phase difference unevenness, and it is preferable because the control of the refractive index ellipsoid becomes easy.

The draw ratio is not particularly limited because it is determined by desired properties, but is usually 1.01 to 10 times, preferably 1.03 to 5 times, and more preferably 1.03 to 3 times. When the draw ratio is 10 times or more, it may be difficult to control the phase difference.
The stretched film may be cooled as it is, but it is heat set by holding it in a temperature atmosphere of Tg-20 ° C. to Tg for at least 10 seconds, preferably 30 seconds to 60 minutes, more preferably 1 minute 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 dimensional shrinkage due to heating of the optical film of the present invention when not subjected to stretching is usually 5% or less, preferably 3% or less, more preferably 1% or less, when heating at 100 ° C. for 500 hours. Especially preferably, it is 0.5% or less.
The dimensional shrinkage ratio of the retardation film of the present invention when heated at 100 ° C. for 500 hours is usually 10% or less, preferably 5% or less, more preferably 3% or less, and particularly preferably 1 % Or less.
In order to make the dimensional shrinkage rate within the above range, in addition to selection of a specific monomer that is a raw material of the resin used in the present invention and selection of other copolymerizable monomers, conditions for a casting method and a stretching method It is also an effective means to adjust.

  In the film stretched as described above, molecules are oriented by stretching and give a retardation to transmitted light. This retardation can be controlled by a stretching ratio, a stretching temperature, a film thickness, or the like. . For example, when the thickness of the film before stretching is the same, the larger the stretching ratio, the larger the absolute value of the retardation of transmitted light tends to increase. Therefore, the desired retardation can be transmitted by changing the stretching ratio. A retardation film applied to light can be obtained. On the other hand, when the stretch ratio is the same, the greater the thickness of the film before stretching, the greater the absolute value of the retardation of transmitted light tends to increase. Therefore, by changing the thickness of the film before stretching, the desired value can be obtained. A retardation film that imparts retardation to transmitted light can be obtained. Further, in the above stretching processing temperature range, the lower the stretching temperature, the larger the absolute value of the retardation of the transmitted light tends to increase. Can be obtained.

The retardation value given to the transmitted light by the retardation film obtained by stretching as described above is determined according to its use and is not particularly limited, but a liquid crystal display element, an electroluminescence display element, or a laser optical system. When used for a wavelength plate, the thickness is usually 1 to 10,000 nm, preferably 10 to 2,000 nm, and more preferably 15 to 1,000 nm.
The retardation of light transmitted through the retardation film is preferably highly uniform, and the variation in retardation at a wavelength of 550 nm is usually ± 20% or less, preferably ± 10% or less, More preferably, it is ± 5% or less. When the variation in phase difference exceeds ± 20%, when used in a liquid crystal display element or the like, color unevenness or the like may occur and display performance may deteriorate.

  Further, the ratio of the phase difference Re (550) of transmitted light having a wavelength of 550 nm to the phase difference Re (400) of transmitted light having a wavelength of 400 nm: Re (400) / Re (550) is in the range of 1.5 to 1.0. And the ratio of the phase difference Re (550) to the phase difference Re (800) of the transmitted light having a wavelength of 800 nm: Re (800) / Re (550) is in the range of 1.0 to 0.5, When used as a phase difference plate for a liquid crystal display element, it is possible to optically compensate for the phase difference of light that has passed through the liquid crystal layer, which is useful for ensuring the clarity of an image and finely adjusting the color tone.

  In addition, the direction in which the refractive index in the plane of the optical film is maximum is the x-axis, the direction in the plane perpendicular to the x-axis is the y-axis, and the thickness direction perpendicular to the plane is the z-axis. In the refractive index ellipsoid, the degree of anisotropy of the refractive index represented by (Nx + Ny) / 2−Nz is ± 0.1 when the respective refractive indexes are represented by Nx, Ny, and Nz. When the optical film is used as a member of an STN liquid crystal display element, for example, within ± 0.001, more preferably within ± 0.01, further preferably within ± 0.005, particularly preferably within ± 0.001. The viewing angle dependency is preferably reduced.

The retardation film of the present invention can be used as a retardation plate alone, in a laminate of two or more, or bonded to a transparent substrate or the like. Moreover, the said phase difference plate can be laminated | stacked and used for another film, a sheet | seat, and a board | substrate. When laminating, a pressure-sensitive adhesive or an adhesive can be used. As these pressure-sensitive adhesives and adhesives, those excellent in transparency are preferable, and specific examples include pressure-sensitive adhesives such as natural rubber, synthetic rubber, vinyl acetate / vinyl chloride copolymer, polyvinyl ether, acrylic, and modified polyolefin resin. And curable pressure-sensitive adhesives in which a curing agent such as an isocyanate group-containing compound is added to the resin having a functional group such as a hydroxyl group or an amino group, a polyurethane-based dry laminate adhesive, a synthetic rubber-based adhesive, an epoxy-based adhesive Agents and the like.
Moreover, in order to improve the workability | operativity of lamination | stacking with another film sheet, a board | substrate, etc., said adhesive film or retardation plate can laminate | stack an adhesive layer or an adhesive bond layer previously. When laminating, the above-mentioned pressure-sensitive adhesive or adhesive can be used as the pressure-sensitive adhesive or adhesive.

<Optical film having a transparent conductive layer>
In the optical film of the present invention, a transparent conductive layer can be laminated on at least one surface thereof. As a material for forming the transparent conductive layer, metals such as Sn, In, Ti, Pb, Au, Pt, and Ag, or oxides thereof are generally used. Moreover, you may oxidize after that as needed. There is also a method of forming an oxide layer from the beginning, but first, a film is formed in the form of a simple metal or a lower oxide, and then subjected to an oxidation treatment such as heat oxidation, anodization or liquid phase oxidation to be transparent. It can also be converted. These transparent conductive layers can be bonded to sheets and films having other transparent conductive layers, or by plasma polymerization, sputtering, vacuum deposition, plating, ion plating, spraying, electrolytic deposition, etc. It is directly formed on the optical film of the present invention. The thickness of these transparent conductive films is determined by desired properties and is not particularly limited, but is usually 10 to 10,000 angstroms, preferably 50 to 5,000 angstroms.

  When the transparent conductive layer is directly formed on the optical film of the present invention, an adhesive layer and an anchor coat layer may be formed between the film and the transparent conductive layer as necessary. Examples of the adhesive layer include heat-resistant resins such as epoxy resin, polyimide, polybutadiene, phenol resin, and polyetheretherketone. Moreover, as an anchor coat layer, what contains what is called acrylic prepolymers, such as epoxy diacrylate, urethane diacrylate, polyester diacrylate, etc. are used. As a curing method, a known method can be used, and for example, UV curing, thermal curing, or the like is used.

  The optical film having the transparent conductive layer of the present invention can be combined with a polarizing film to form a laminate. The method for combining the optical film having the transparent conductive layer of the present invention and the polarizing film is not particularly limited, and the transparent conductive layer of the present invention is provided on at least one side of the polarizing film in which a protective film is laminated on both sides of the polarizing film. The optical film may be laminated on the side opposite to the transparent conductive layer forming surface via an appropriate adhesive or pressure-sensitive adhesive, or the transparent conductive layer of the present invention may be used instead of the protective film for the polarizing film. The optical film may be used and laminated on the polarizing film via a suitable adhesive or pressure-sensitive adhesive on the side opposite to the transparent conductive layer forming surface. Of course, the optical film of the present invention having no transparent conductive layer can also be used as a protective film for a polarizing film. In such a case, when the retardation film of the present invention is used as a protective film, the protective film has a function as a retardation plate, and therefore there is an advantage that it is not necessary to bond the retardation plate again to the polarizing film.

  In addition, the optical film having the transparent conductive layer of the present invention may contain a gas barrier material such as polyvinylidene chloride or polyvinyl alcohol for at least one of the films for the purpose of reducing the permeation of oxygen or water vapor as necessary. It can also be laminated on the surface. Further, for the purpose of improving the scratch resistance and heat resistance of the film, a hard coat layer may be laminated on the gas barrier layer. As the hard coat agent, organic hard coat materials such as organic silicon resins, melamine resins, epoxy resins, and acrylic resins, or inorganic hard coat materials such as silicon dioxide can be used. Of these, hard coat materials such as organic silicon resins and acrylic resins are preferred. Among organosilicon resins, those having various functional groups are used, but those having an epoxy group are preferred.

<Optical film having an antireflection layer>
In the optical film of the present invention, an antireflection layer can be laminated on at least one surface thereof. As a method for forming the antireflection layer, for example, a commonly used inorganic type made of a metal oxide such as silicon, titanium, tantalum or zirconium, for example, vinylidene fluoride, hexafluoropropylene, tetrafluoroethylene Sputtering, vapor deposition, coating, dipping, etc. with an organic antireflection film made of a fluorine-containing compound such as a (co) polymer or fluorine-containing (meth) acrylate (co) polymer in a thickness of about 0.01 to 10 μm. It can be turned on by the method. The thickness of the antireflection layer is usually 0.01 to 50 μm, preferably 0.1 to 30 μm, and more preferably 0.5 to 20 μm. When the thickness is less than 0.01 μm, the antireflection effect cannot be exhibited.

Further, a known hard coat layer or antifouling layer may be laminated on the optical film having the antireflection layer of the present invention. Moreover, said transparent conductive layer may be laminated | stacked. Further, it may have a function of giving a phase difference to transmitted light, or may have a light diffusion function.
By having a plurality of functions as described above, the optical film having the antireflection layer of the present invention, for example, when used in a liquid crystal display element, the antireflection film is a retardation plate, a light diffusion film, a polarizing plate protective film. Alternatively, some of the electrode substrates (transparent conductive layers) are also used, and the number of parts can be reduced as compared with the conventional case.

<Application>
The optical film of the present invention includes various liquid crystal display elements such as mobile phones, digital information terminals, pagers, navigation, in-vehicle liquid crystal displays, liquid crystal monitors, light control panels, displays for OA equipment, and displays for AV equipment, It can be used for an electroluminescence display element or a touch panel. It is also useful as a wave plate used in an optical disk recording / reproducing apparatus such as a CD, CD-R, MD, MO, and DVD.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated more concretely, this invention is not limited to a following example, unless the summary is exceeded. In the following, “parts” and “%” mean “parts by weight” and “% by weight” unless otherwise specified.
Various measurement methods are shown below.
[Glass transition temperature (Tg)]
Using a differential scanning calorimeter (DSC) manufactured by Seiko Instruments Inc., the measurement was performed under conditions of nitrogen atmosphere and heating rate: 20 ° C./min.
[Saturated water absorption]
In accordance with ASTM D570, the sample was immersed in water at 23 ° C. for 1 week, and the change in weight before and after immersion was measured and determined.
[Total light transmittance, haze]
Haze meter manufactured by Suga Test Instruments Co., Ltd .: Measured using HGM-2DP type.
[Phase difference of transmitted light]
The phase difference measurement of the transmitted light was performed using KOBRA-21ADH manufactured by Oji Scientific Instruments and KOBRA-CCD. The measurement was carried out 10 times at different locations for each sample, and the average value was taken as the phase difference of the sample. Further, the dispersion of the phase difference was obtained by the following formula.
Re (m) / Re (A) × 100
Re (m): Absolute value of the difference between the maximum value or the minimum value and the average value.
Use the one with the larger absolute value to calculate the variation.
Re (A): Average value

<Synthesis Example 1>
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2.5, 1 ^7.10] -3- dodecene and (specific monomer D) 200 parts of 5- (4-biphenyl carbonyl oxymethyl) bicyclo [ 2.2.1] 50 parts of hept-2-ene (specific monomer A), 18 parts of 1-hexene (molecular weight regulator) and 750 parts of toluene were charged into a nitrogen-substituted reaction vessel, and this solution was charged. Heated to 60 ° C. Next, 0.62 parts of a toluene solution of triethylaluminum (1.5 mol / l) as a polymerization catalyst and tungsten hexachloride modified with t-butanol and methanol (t-butanol: methanol: tungsten) were added to the solution in the reaction vessel. = 0.35 mol: 0.3 mol: 1 mol) of a toluene solution (concentration 0.05 mol / l) 3.7 parts was added, and the system was heated and stirred at 80 ° C. for 3 hours to open the ring. Polymerization reaction was performed to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%, and the intrinsic viscosity (η _inh ) of the obtained ring-opened polymer measured in chloroform at 30 ° C. was 0.66 dl / g.

The autoclave was charged with 4,000 parts of the ring-opening polymer solution thus obtained, and 0.48 part of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution. Then, the hydrogenation reaction was performed 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 165 ° C.
After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a coagulated product, which was dried to obtain a hydrogenated polymer.

The hydrogenated polymer thus obtained (hereinafter referred to as “resin (a-1)”) was measured for the hydrogenation rate of olefinically unsaturated bonds using 400 MHz and ¹ H-NMR. 9%, while the aromatic ring was not substantially hydrogenated. Moreover, it was 160 degreeC when the glass transition temperature (Tg) was measured by the DSC method about the said resin (a-1). Moreover, when the number average molecular weight (Mn) and weight average molecular weight (Mw) of polystyrene conversion were measured by the GPC method (solvent: tetrahydrofuran) about the said resin (a-1), the number average molecular weight (Mn) was 47 ,. 000, the weight average molecular weight (Mw) was 187,000, and the molecular weight distribution (Mw / Mn) was 3.98. Moreover, when the saturated water absorption rate at 23 ° C. was measured for the resin (a-1), it was 0.3%. Further, the SP value was measured and found to be 19 (MPa ^1/2 ). Further, the intrinsic viscosity (η _inh ) of the resin (a-1) measured in chloroform at 30 ° C. was 0.68 dl / g.

<Synthesis Example 2>
As monomers, 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2.5, 1 ^7.10] -3- dodecene and (specific monomer D) 175 parts of 1,4-methano -1 , 4,4a, 9a-tetrahydrofluorene (also known as: 1H, 4H, 4aH, 9aH-1,4-methanofluorene) (specific monomer B) Resin (b-1) was obtained. The hydrogenation rate of the olefinically unsaturated bond of the resin (b-1) measured by 400 MHz and ¹ H-NMR was 99.9%, and the aromatic ring was not substantially hydrogenated. When the Tg of the resin was 155 ° C. and the polystyrene-equivalent number average molecular weight (Mn) and weight average molecular weight (Mw) were measured by the GPC method (solvent: tetrahydrofuran), the number average molecular weight (Mn) was 32,000, The weight average molecular weight (Mw) was 120,000, and the molecular weight distribution (Mw / Mn) was 3.75. Moreover, it was 0.2% when the saturated water absorption rate in 23 degreeC was measured about the said resin (b-1). Moreover, it was 0.61 dl / g when intrinsic viscosity ((eta) inh) was measured.

<Synthesis Example 3>
As monomers, 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2.5, 1 ^7.10] and 3- dodecene (specific monomer D) 200 parts, 1,2-(2H, Hydrogenated resin (c-1) in the same manner as in Synthesis Example 1 except that 50 parts of 3H- [1,3] epicyclopenta) -1,2-dihydroacenaphthylene (specific monomer C) was used ) The hydrogenation rate of the olefinically unsaturated bond of the resin (c-1) measured by 400 MHz and ¹ H-NMR was 99.9%, and the aromatic ring was not substantially hydrogenated. When the Tg of the resin was 175 ° C. and the polystyrene-equivalent number average molecular weight (Mn) and weight average molecular weight (Mw) were measured by the GPC method (solvent: tetrahydrofuran), the number average molecular weight (Mn) was 42,000. The weight average molecular weight (Mw) was 180,000, and the molecular weight distribution (Mw / Mn) was 4.29.

<Comparative Synthesis Example 1>
As monomers, 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2.5, 1 ^7.10] -3- dodecene except for using (specific monomer D) only 250 parts of Synthesis Example 1 In the same manner as above, a hydrogenated resin (d-1) was obtained. The hydrogenation rate of the olefinically unsaturated bond of the resin (d-1) measured by 400 MHz and ¹ H-NMR was 99.9%. When the Tg of the resin was 170 ° C. and the polystyrene-equivalent number average molecular weight (Mn) and weight average molecular weight (Mw) were measured by the GPC method (solvent: tetrahydrofuran), the number average molecular weight (Mn) was 38,000, The weight average molecular weight (Mw) was 122,000, and the molecular weight distribution (Mw / Mn) was 3.21.

[Example 1]
The resin (a-1) is dissolved in toluene so as to have a concentration of 30% (solution viscosity at room temperature is 30,000 mPa · s), and is made hydrophilic with an acrylic acid system using an INVEX laboratory coater manufactured by Inoue Metal Industry ( (Easy adhesion) The surface-treated PET film having a thickness of 100 μm (Lumirror U94, manufactured by Toray Industries, Inc.) was applied so that the film thickness after drying was 100 μm, and this was subjected to primary drying at 50 ° C. Secondary drying was performed at 90 ° C. The resin film peeled off from the PET film was designated as (a-2). The residual solvent amount of the obtained film was 0.5%.

The photoelastic coefficient (C _P ) and stress optical coefficient (C _R ) of this film (a-2) are measured by a known method (Polymer Journal, Vol. 27, No. 9, P. 943-950 (1995)). Asked. That is, the photoelastic coefficient (C _P ) was calculated from a phase difference generated at a room temperature (25 ° C.) and a stress applied to the sample at that time by applying a certain constant load to a strip-shaped film sample at room temperature (25 ° C.). For the stress optical coefficient (C _R ), the phase difference generated after slowly cooling to room temperature by extending several percent under several constant loads at Tg or higher using a film-like sample was measured, Calculated from the applied stress. The results were C _P = 5 (× 10 ⁻¹² Pa ⁻¹ ) and C _R = 2900 (× 10 ⁻¹² Pa ⁻¹ ).

This film was heated in a tenter to 165 ° C., which is Tg + 5 ° C., stretched 1.08 times at a stretching rate of 400% / min, and then cooled while maintaining this state for about 2 minutes in an atmosphere at 140 ° C. When the film was further cooled to room temperature and taken out, a 94 μm-thick retardation film (a-3) was obtained that gave a transmitted light 140 nm retardation at a wavelength of 550 nm. In addition, a 90 μm-thick retardation film (a-4) was obtained in the same manner as described above except that the draw ratio was 1.28 times, and a retardation of 280 nm was given to transmitted light at a wavelength of 550 nm.
The retardation films (a-3) and (a-4) thus obtained were measured for variations in total light transmittance, haze, and retardation of transmitted light. The results are shown in Table 1. Further, FIG. 1 shows the wavelength dependence of the phase difference of transmitted light with respect to the laminated body bonded so that the optical axes of (a-3) and (a-4) intersect each other at 62 degrees.

[Example 2]
Resin (b-1) was dissolved in toluene to a concentration of 30% (solution viscosity at room temperature is 29,000 mPa · s), and 100 μm having a residual solvent amount of 0.5% was obtained in the same manner as in Example 1. A resin film (b-2) having a thickness was obtained.
When the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) of this film (b-2) were measured in the same manner as in Example 1, C _P = 10 (× 10 ⁻¹² Pa ⁻¹ ), C _R = 2400 (× 10 ⁻¹² Pa ⁻¹ ).
Further, the film (b-2) was heated to 160 ° C. which is Tg + 5 ° C. in the tenter in the same manner as in Example 1, and stretched 1.30 times at a stretching rate of 400% / min, and then an atmosphere at 135 ° C. Under cooling for about 2 minutes under this condition, the film was cooled to room temperature and taken out. As a result, a 90 μm-thick retardation film (b-3) giving a transmitted light of 270 nm at a wavelength of 550 nm was obtained. It was.
The retardation film (b-3) thus obtained was measured for variations in total light transmittance, haze, and retardation of transmitted light. The results are shown in Table 1.

[Example 3]
Resin (c-1) was dissolved in toluene so as to have a concentration of 30% (solution viscosity at room temperature is 40,000 mPa · s), and 100 μm thickness with a residual solvent amount of 0.6% was obtained in the same manner as in Example 1. Of resin film (c-2) was obtained.
When the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) of this film (c-2) were measured in the same manner as in Example 1, C _P = 15 (× 10 ⁻¹² Pa ⁻¹ ), C _R = 2,500 (× 10 ⁻¹² Pa ⁻¹ ).
Further, the film (c-2) was heated to 180 ° C., which is Tg + 5 ° C., in the tenter in the same manner as in Example 1, and stretched 1.31 times at a stretching rate of 400% / min, and then the atmosphere at 155 ° C. The film was cooled while maintaining this state for about 2 minutes, and further cooled to room temperature and taken out. As a result, a 90 μm-thick retardation film (c-3) giving a phase difference of 280 nm to transmitted light at a wavelength of 550 nm was obtained. It was.
The retardation film (c-3) thus obtained was measured for variations in total light transmittance, haze, and retardation of transmitted light. The results are shown in Table 1.

[Comparative Example 1]
Resin (d-1) was dissolved in toluene so as to have a concentration of 30% (solution viscosity at room temperature is 31,000 mPa · s), and 100 μm having a residual solvent amount of 0.5% as in Example 1. A resin film (d-2) having a thickness was obtained.
When the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) of this film (d-2) were measured in the same manner as in Example 1, C _P = 4 (× 10 ⁻¹² Pa ⁻¹ ), C _R = 1,440 (× 10 ⁻¹² Pa ⁻¹ ).
In the same manner as in Example 1, the film (d-2) was heated to 175 ° C., which is Tg + 5 ° C., and stretched 1.30 times at a stretching rate of 400% / min. Cooling while maintaining this state for about 2 minutes, further cooling to room temperature and taking out, a 90 μm-thick retardation film (d-3) giving a transmitted light of 97 nm retardation at a wavelength of 550 nm was obtained. . Moreover, when it extended | stretched similarly to the above except having made the draw ratio 1.70 time, the 85-micrometer-thick retardation film (d-4) which gives a retardation of 184 nm to transmitted light in wavelength 550nm was obtained.
The retardation films (d-3) and (d-4) thus obtained were measured for variations in total light transmittance, haze, and retardation of transmitted light. The results are shown in Table 1.

[Comparative Example 2]
Using a commercially available bisphenol A type polycarbonate resin (product number: C-1400 manufactured by Teijin Limited), a resin film (e-1) having a residual solvent amount of 0.5% and a thickness of 100 μm was obtained in the same manner as in Example 1. It was. When the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) of the film (e-1) were measured in the same manner as in Example 1, C _P = 150 (× 10 ⁻¹² Pa ⁻¹ ), C _R = 4,700 (× 10 ⁻¹² Pa ⁻¹ ).
In the same manner as in Example 1, the film (e-1) was heated to 150 ° C., which is Tg + 5 ° C., and stretched 1.30 times at a stretching rate of 400% / min. Cooling while maintaining this state for about 2 minutes, further cooling to room temperature and taking out, a phase difference film (e-2) having a thickness of 90 μm which gives a phase difference of 520 nm to transmitted light at a wavelength of 550 nm was obtained. . Further, when the film was stretched in the same manner as described above except that the stretch ratio was 1.05, a 95 μm-thick retardation film (e-3) was obtained which gave a transmitted light having a phase difference of 280 nm at a wavelength of 550 nm.
The retardation films (e-2) and (e-3) thus obtained were measured for variations in total light transmittance, haze, and retardation of transmitted light. The results are shown in Table 1.

[Example 4, Comparative Example 3]
The retardation films (a-4), (b-3), (c-3), and (e-3) obtained in Examples 1 to 3 and Comparative Example 2 are cut into 10 cm squares, and the two opposite sides A 1 cm × 10 cm aluminum plate was attached to each using a cyanoacrylate adhesive (Aron Alpha “High Speed EX”, manufactured by Konishi Co., Ltd.) (adhesive surface: 0.5 cm × 10 cm). Manufactured. Next, the sample was suspended in the air through an aluminum plate, and a load of 100 g was applied through the other aluminum plate, and the glass transition temperature of the resin constituting each retardation film was kept at a temperature atmosphere of −50 ° C. for 24 hours. Left to stand. Thereafter, the sample was taken out and cooled to room temperature, and the phase difference of transmitted light at 550 nm was measured. The results are shown in Table 2.

  As is clear from the comparison between Examples 1 to 3 and Comparative Example 1, the optical film containing the thermoplastic norbornene-based resin having the essential structural unit of the present invention is a thermoplastic norbornene-based that does not have the essential structural unit. Compared to an optical film containing a resin, the retardation imparted to transmitted light is large even at the same stretch ratio, and processing for obtaining a desired retardation film is easy. Moreover, even if it has the essential structural unit of this invention, the dispersion | variation in a phase difference is very small, and the characteristic of the film of the thermoplastic norbornene-type resin recognized conventionally is maintained.

Furthermore, as is clear from the comparison between Examples 1 to 3 and Comparative Example 2, the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ) are made of a polycarbonate resin that is out of the scope of the present invention. In the case of a phase difference film, there is a problem in the uniformity of the phase difference of transmitted light.
Further, as is clear from Table 2, in the case of a retardation film made of a polycarbonate resin whose photoelastic coefficient (C _P ) and stress optical coefficient (C _R ) are out of the scope of the present invention, the retardation of transmitted light is changed. There is a problem that it is easy to change depending on the environment where the function to be given is placed and the phase difference cannot be stabilized.

[Example 5]
Each of the films (a-3), (b-3), and (c-3) is subjected to sand mat treatment, and has an optical film (a-) having a light diffusion function of 55% haze and 93% total light transmittance. 5), (b-6) and (c-6) were obtained. In addition, no changes were observed in haze or total light transmittance even after leaving in a high temperature and high humidity chamber at a temperature of 80 ° C. and a humidity of 90% for 500 hours.

[Example 6]
A transparent conductive film is formed by sputtering on one side of each of the films (a-3), (b-3), and (c-3) using a target made of indium oxide / tin oxide (weight ratio 95: 5). Transparent conductive films (a-6), (b-7) and (c-7) were obtained. With respect to this transparent conductive film, the transparency and appearance of the film (the presence or absence of scratches, the degree of warping of the film) were observed visually. Further, an endurance test was conducted for 500 hours under conditions of 80 ° C. and 90% relative humidity, and the appearance change (humidity resistance) was visually observed. As a result, all of the transparent conductive films had a total light transmittance of more than 85% and good transparency, and the film appearance was good with no scratches, warpage or undulation.

[Example 7]
Each surface of films (a-3), (b-3), and (c-3) is coated with JSR Co., Ltd. OPSTAR JN7212 so as to have a dry film thickness of 0.1 μm, and an antireflection layer is formed. Films (a-7), (b-8) and (c-8) were obtained. All of the films exhibited a good antireflection property with a reflectance of 1% or less.

[Example 8]
On the surface of the polarizing film obtained by uniaxially stretching the polyvinyl alcohol film having a thickness of 50 μm up to 4 times in about 5 minutes while immersing it in a 40 ° C. bath composed of 5 g of iodine, 250 g of potassium iodide, 10 g of boric acid, and 1000 g of water, 75% by weight acetic acid of adduct of 100 parts of acrylic resin consisting of 90% by weight of n-butyl acrylate, 7% by weight of ethyl acrylate and 3% by weight of acrylic acid and trimethylolpropane (1 mole) adduct of tolylene diisocyanate (3 moles) A film (a-2), (b-2) or (c-2) is laminated on both sides using a pressure-sensitive adhesive obtained by mixing a crosslinking agent comprising 2 parts of an ethyl solution, and a polarizing plate (a- 8), (b-9) and (c-9) were obtained. The polarizing plate was subjected to a durability test for 500 hours under the conditions of 80 ° C. and 90% relative humidity, and when the appearance change was visually observed, no abnormality in the appearance such as whitening or blistering was observed. Also, it was found that the degree of polarization of 95% or more with respect to the initial value was maintained, and it had good durability.

[Example 9]
A film (a-9) was obtained in the same manner as in Example 1 except that a matte-treated PET film with surface irregularities was used as the PET film. The film had a haze of 10% and a total light transmittance of 93%. In addition, no change was observed in haze or total light transmittance even after leaving in a high temperature and high humidity chamber at a temperature of 80 ° C. and a humidity of 90% for 500 hours.

It is a figure which shows the wavelength dependence of the phase difference given to the transmitted light of the phase difference plate which laminated | stacked phase difference film (a-3) obtained in Example 1, and (a-4).

Claims (7)

The following general formula (1):

[Wherein, n is 0 or 1, and m is 0 or an integer of 1 or more. X is independently a group represented by the formula: —CH═CH— or a group represented by the formula: —CH ₂ CH ₂ —, and R ¹ , R ² , R ³ and R ⁴ are each independently a hydrogen atom A halogen atom; a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms which may have a linking group containing oxygen, nitrogen, sulfur or silicon; or a polar group, or R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ are bonded to each other to form a carbocyclic or heterocyclic ring (these carbocyclic or heterocyclic rings may have a monocyclic structure, or other rings may be condensed to form a polycyclic ring A structure may be formed). The formed carbocyclic or heterocyclic ring may be an aromatic ring or a non-aromatic ring. ]
In made of a polymer consisting of structural units a represented, based on the 5 to 30 wt% of structural units a in the polymer, at least one of R ¹ to R ⁴ is represented by the following general formula (2) and either a or R ² and R ³ are formed by bonding to each other, has at least one group selected from the following general formula (3) or (4), the following general The structural unit a having the structural unit a derived from the monomer (specific monomer D) represented by the formula (8) and having the group represented by the general formula (2) is 5- ( 4-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (4-biphenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene, 5- (4- Biphenylcarbonyloxypropyl) bicyclo [2.2.1] hept-2-ene, 5- Methyl-5- (4-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (2-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (2-biphenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene, 5-methyl-5- (2-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2- Ene, 5- (3-biphenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (3-biphenylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene, 5- (1-naphthylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (1-naphthylcarbonyloxyethyl) bicyclo [2. 2.1] hept-2-ene, 5-methyl-5- (1-naphthylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (2-naphthylcarbonyloxymethyl) bicyclo [ 2.2.1] hept-2-ene, 5- (2-naphthylcarbonyloxyethyl) bicyclo [2.2.1] hept-2-ene, 5-methyl-5- (2-naphthylcarbonyloxymethyl) Methylbicyclo [2.2.1] hept-2-ene, 5- (9-anthracenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, 5- (9-anthracenylcarbonyl) Oxyethyl) bicyclo [2.2.1] hept-2-ene, 5-methyl-5- (9-anthracenylcarbonyloxymethyl) bicyclo [2.2.1] hept-2-ene, - (4-biphenyl carbonyl oxymethyl) tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] -3-dodecene, 8- (4-biphenylcarbonyloxyethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8- (4-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8- (2-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8- (2-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8- (3-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8- (3-biphenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8- (1-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8- (1-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8- (2-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8- (2-naphthylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8- (9-anthracenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8- (9-anthracenylcarbonyloxymethyl) tetracyclo [4.4.0.1 ^2,5 . A structural unit a having a structure derived from at least one specific monomer A selected from 1 ^7,10 ] -3-dodecene and having a group represented by the general formula (3): 1,2- (2H, 3H- [1,3] epicyclopenta) -1,2-dihydroacenaphthylene represented by the following formula (a):

Diels-Alder adduct of 1,2- (2H, 3H- [1,3] epicyclopenta) -1,2-dihydroacenaphthylene and cyclopentadiene represented by the following formula (b):

Or, the hydrogen atom of these aromatic rings is derived from at least one specific monomer B selected from the specific monomer B which is a substituted product in which a hydrogen atom is substituted with a halogen atom or a hydrocarbon group having 1 to 10 carbon atoms. The structural unit a having a structure and having a group represented by the general formula (4) is 1,4-methano-1,4,4a, 9a-tetrahydrofluorene, 1,4-methano-1 4,4a, 9,9a, 10-hexahydroanthracene, 1,4-methano-1,4,4a, 9,10,10a-hexahydrophenanthrene, 11,12-benzo-pentacyclo [6.5. .1 ^3,6 . 0 ^2,7 . 0 ^9,13] -4-pentadecene, 11,12-benzo - pentacyclo [6.6.1.1 ^{3, 6.} 0 ^2,7 . 0 ^9,14] -4-hexadecene, 1,4-methano -1,4,4a, 9a- tetrahydronaphthalene dibenzofuran, 1,4-methano -1,4,4a, 9a- tetrahydrocarbazole, 1,4-methano - It has a structure derived from at least one specific monomer C selected from 1,4,4a, 10a-tetrahydroanthraquinone, and has a photoelastic coefficient (C _P ) of 0 to 50 (× 10 ⁻¹² Pa ^{− 1} ) and a thermoplastic norbornene-based resin having a stress optical coefficient (C _R ) of 1900 to 4000 (× 10 ⁻¹² Pa ⁻¹ ).
— (CH ₂ ) _p —O—C (O) —R ⁵ (2)
[Wherein, p is an integer of 1 to 5 and R ⁵ is a biphenylyl group, a naphthyl group (α or β), an anthracenyl group, or a hydrogen atom of these groups is a halogen atom, or a hydrocarbon group having 1 to 10 carbon atoms. Represents a group substituted by. ]

[Wherein, R ¹ and R ⁴ are as defined in relation to the general formula (1), and R ^{6 to} R ¹¹ each independently represent a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur or silicon. A substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms that may have; or a monovalent polar group. ]

[Wherein, R ¹ and R ⁴ are as defined above, and R ^{12 to} R ¹⁵ each independently represent a hydrogen atom; a halogen atom; an optionally substituted group containing oxygen, nitrogen, sulfur or silicon. Or an unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms; or a monovalent polar group. V and W are independently a single bond or —O—, —CO—, —NR ¹⁶ —, — (CR ¹⁷ R ¹⁸ ) _q — (where q = 1 to 5), —COO— and —OCO—. R ^{16 to} R ¹⁸ each independently represents a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group, or an aromatic group. Represents a hydrocarbon group. ]

[In formula (8), h = 1, i = 0, R ¹ , R ² , R ³ and R ⁴ each independently have a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur or silicon. A substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; or a polar group, or R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ bonded to each other Thus, a carbocycle or a heterocycle (these carbocycles or heterocycles may be monocyclic structures or other rings may be condensed to form a polycyclic structure) may be formed. The formed carbocyclic or heterocyclic ring may be an aromatic ring or a non-aromatic ring. However, any three of R ^{1 to} R ⁴ are a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and the remaining one is a polar group represented by the following formula (9). However, at least one of R ^{1 to} R ⁴ has a group represented by the above general formula (2), or the above general formula (R ² and R ³ are bonded to each other). The structural unit a having at least one group selected from 3) or (4) is excluded. ]

[z is 0 to 5, and R ¹⁹ represents a monovalent alkyl group, an aryl group, or a heterocyclic ring. ]   2. The optical film according to claim 1, comprising a thermoplastic norbornene-based resin made of a polymer containing a structural unit a in which n = 0 and m = 1 in the general formula (1).   2. The optical film according to claim 1, wherein the optical film has a light diffusion function on at least one side.   The optical film according to claim 1, further comprising a transparent conductive layer on at least one side.   The optical film according to claim 1, further comprising an antireflection layer on at least one side.   A polarizing plate protective film comprising the optical film according to claim 1.   A polarizing plate comprising the optical film according to claim 1.

Images