KR20210110644A - Polyamide-based resin, optical film and flexible display device - Google Patents

Abstract

[식(1) 중, Ar¹은, 탄소수 1∼12의 플루오로알킬기를 가지는 2가의 방향족기를 나타내고,
X¹은 2가의 유기기를 나타낸다]
로 나타내어지는 구성 단위, 및, 식(3):

[식(3) 중, Z¹은, Ar¹을 나타내거나, 또는 Ar¹이 아닌 2가의 유기기를 나타내고,
Ar¹은 상기 식(1)에 있어서 정의한 대로이며,
X²는, 2가의 유기기를 나타내고, 단 Z¹이 Ar¹을 나타내는 경우, 식(1) 중의 X¹과 식(3) 중의 X²는 서로 상이하다]
으로 나타내어지는 구성 단위를 적어도 가지는, 중량 평균 분자량이 200,000∼1,000,000인 폴리아미드계 수지를 포함하는 광학 필름.An optical film having a high elastic modulus and a low humidity expansion coefficient is provided.
Equation (1):

[In formula (1), Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,
X ¹ represents a divalent organic group]
A structural unit represented by, and Equation (3):

Equation (3) of the, Z ¹ is represented by Ar ^1, or Ar ¹ represents a divalent organic group non-,
Ar ¹ is as defined in the above formula (1),
X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;
An optical film comprising a polyamide-based resin having at least a structural unit represented by and having a weight average molecular weight of 200,000 to 1,000,000.

Description

Polyamide-based resin, optical film and flexible display device

The present invention relates to an optical film containing a polyamide-based resin, a flexible display device including the optical film, and a polyamide-based resin.

BACKGROUND ART At present, display devices such as a liquid crystal display device and an organic EL display device are widely utilized not only for televisions but also for various applications such as mobile phones and smart watches. Conventionally, glass has been used as a front plate of such a display device. However, while glass has high transparency and can exhibit high hardness depending on the type, it is very rigid and brittle, so it is difficult to use it as a front panel material for a flexible display device.

Therefore, the utilization of a polymer material as a material instead of glass is examined. Since the front plate made of a polymer material easily exhibits flexible properties, it is expected to be used for various purposes. As one of the flexible polymer materials, for example, an optical film using a polyamide-based resin has been studied (Patent Documents 1 and 2).

Japanese Patent Publication No. 2015-521686 Japanese Patent Laid-Open No. 2018-119132

However, when an optical film using a polyamide-based resin is used in a flexible display device or the like, defects such as scratches and wrinkles may occur in the optical film due to bending or contact with external factors. MEANS TO SOLVE THE PROBLEM This inventor examined various means for improving the above, and discovered that it was hard to produce defects, such as a wound, in an optical film by raising the elastic modulus of an optical film. In addition, although a flexible display device is used under various environments over a long period of time, the optical film to which the load was applied especially with changes, such as temperature and humidity, may expand-contract in a planar direction. Therefore, it is also calculated|required that an optical film has a low humidity expansion coefficient with respect to the change of temperature and humidity.

Therefore, this invention makes it a subject to provide the optical film which has a high elastic modulus and low humidity expansion coefficient.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, the present inventors paid attention to the structure of the monomer which comprises polyamide-type resin contained in an optical film, and earnestly examined it. As a result, it was discovered that the optical film containing polyamide-type resin which has a specific structural unit at least and has a weight average molecular weight in a specific range has both a high elastic modulus and a low humidity expansion coefficient, and came to complete this invention.

That is, this invention includes the following suitable aspects.

[1] Formula (1):

[Formula 1]

[In formula (1), Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms, and X ¹ represents a divalent organic group]

A structural unit represented by, and Equation (3):

[Formula 2]

[In formula (3),

Z is ^1, Ar represents a ^1, or Ar ¹ represents a divalent organic group non-, Ar ¹ is as defined in the formula (1),

X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;

An optical film comprising a polyamide-based resin having at least a structural unit represented by and having a weight average molecular weight of 200,000 to 1,000,000.

[2] The optical film according to [1], wherein the fluoroalkyl group having 1 to 12 carbon atoms ^{in Ar 1 in the formula (1) is a perfluoroalkyl group having 1 to 12 carbon atoms.}

[3] The structural unit represented by Formula (1) is Ar ¹ , and Formula (4):

[Formula 3]

[In formula (4),

R ¹ represents a fluoroalkyl group having 1 to 12 carbon atoms,

n and k independently represent an integer of 1 to 4, provided that when n and/or k represents an integer of 2 to 4, a plurality of R ¹ may be the same or different from each other,

* indicates a bonding hand]

The optical film according to [1] or [2], comprising an aromatic group represented by .

[4] The optical film according to [3], wherein the two bonding hands in the formula (4) are located in a para position to each other.

[5] The optical film according to [3] or [4], wherein k in formula (4) is 1 or 2.

^{[6] The optical film according to any one of [3] to [5], wherein R 1} in formula (4) represents a perfluoroalkyl group having 1 to 12 carbon atoms, and n is 1 or 2.

[7] The structural unit represented by Formula (1) and the structural unit represented by Formula (3) are respectively X ¹ and X ² , Formula (5):

[Formula 4]

[In formula (5),

Ar ² represents a divalent aromatic group which may have a substituent,

V is a single bond, -O-, a diphenylmethylene group, a fluorenyl group, a linear, branched or alicyclic divalent hydrocarbon group having 1 to 12 carbon atoms, -SO ₂ -, -S-, -CO- , -PO-, -PO ₂ -, -N(R ^a )- or -Si(R ^b ) ₂ -; , R ^a and R ^b each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

m represents an integer of 0 to 3,

* indicates a bonding hand]

The optical film according to any one of [1] to [6], comprising a divalent organic group represented by .

[8] The optical film according to [7], wherein m in the formula (5) is 1;

[9] Equation (5) is Equation (5a):

[Formula 5]

[In formula (5),

R ² represents a fluoroalkyl group having 1 to 12 carbon atoms,

p and q each independently represent an integer of 1 to 4, provided that when p and/or q represents an integer of 2 to 4, ^{two or} more R 2 may be the same as or different from each other,

* indicates a bonding hand]

The optical film according to [7] or [8], which is represented by .

[10] Equation (5a) is Equation (5c):

[Formula 6]

[* in formula (5c) represents a bond]

The optical film according to the above [9], represented by .

[11] The optical film according to any one of [1] to [10], wherein the thickness is 10-200 µm.

[12] A flexible display device comprising the optical film according to any one of [1] to [11].

[13] The flexible display device according to [12], further comprising a touch sensor.

[14] The flexible display device according to [12] or [13], further comprising a polarizing plate.

[15] Formula (1):

[Formula 7]

[In formula (1),

Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,

X ¹ represents a divalent organic group]

^{, and as Ar 1} in Formula (1), Formula (4):

[Formula 8]

[In formula (4), R ¹ represents a fluoroalkyl group having 1 to 12 carbon atoms,

n and k independently represent an integer of 1 to 4, provided that when n and/or k represents an integer of 2 to 4, a plurality of R ¹ may be the same or different from each other,

* indicates a bond]

A structural unit containing an aromatic group represented by, and Formula (3):

[Formula 9]

Equation (3) of the, Z ¹ is represented by Ar ^1, or Ar ¹ represents a divalent organic group non-,

Ar ¹ is as defined in the above formula (1),

X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;

A polyamide-based resin having a weight average molecular weight of 200,000 to 1,000,000 having at least a structural unit represented by

The optical film of the present invention has a high elastic modulus and a low humidity expansion coefficient.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail. In addition, the scope of the present invention is not limited to the embodiments described herein, and various changes can be made without departing from the spirit of the present invention.

The optical film of the present invention, Formula (1):

[Formula 10]

[In formula (1), Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms, and X ¹ represents a divalent organic group]

A structural unit represented by, and Equation (3):

[Formula 11]

Equation (3) of the, Z ¹ is represented by Ar ^1, or Ar ¹ represents a divalent organic group non-,

Ar ¹ is as defined in the above formula (1),

X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;

and a polyamide-based resin having a weight average molecular weight of 200,000 to 1,000,000 having at least a structural unit represented by . In addition, in Formula (1) and Formula (3), the bond shown by the dotted line shows the bond couple|bonded with the adjacent structural unit. In this specification, the bond shown by the dotted line in another chemical structural formula also shows the bond couple|bonded with the adjacent structural unit or group similarly.

The polyamide-type resin contained in the optical film of this invention may have one type of structural unit represented by Formula (1), and may have two or more types of structural units represented by Formula (1). Similarly, the said polyamide-type resin may have one type of structural unit represented by Formula (3), and may have two or more types of structural units represented by Formula (3). The structural unit represented by Formula (1) and the structural unit represented by Formula (3) are structural units which a dicarboxylic acid compound and a diamine compound react, and are formed. In this specification, the structural unit represented by Formula (1) is also called "structural unit (1)", and the structural unit represented by Formula (3) is also called "structural unit (3)." Moreover, when the polyamide-type resin contained in the optical film of this invention has two or more types of structural units represented by Formula (1), at least 1 structural unit of the said structural unit is a structural unit represented by Formula (1). , and at least one other structural unit may be a structural unit represented by Formula (3).

When the polyamide-based resin has a structural unit represented by the formula (1) and a structural unit represented by the formula (3), the polyamide-based resin is

(a) has at least a structural unit represented by Formula (1) and a structural unit represented by Formula (3) in which Z ¹ represents a divalent organic group not corresponding to Ar ¹ , in this case, X in Formula (1) ^{1 and X 2} in formula (3) may be the same as or different from each other, or

(b) at least a structural unit represented by Formula (1) and a structural unit represented by ^{Formula (3) where Z 1} corresponds to Ar ¹ , in this case, X ¹ and Formula (3) in Formula (1) X ^{2 in} is different from each other

indicates that In the case of said (a), the structural unit represented by Formula (3) is Formula (3a):

[Formula 12]

[In formula (3a), Z ² represents a divalent organic group that is not a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,

X ³ represents a divalent organic group]

, and in the case of (b), the structural unit represented by Formula (3) is Formula (3b):

[Formula 13]

[In formula (3a), Ar ³ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,

X ⁴ represents a divalent organic group different from ^{X 1} in formula (1)]

is represented by In this specification, the structural unit represented by Formula (3a) is also called "structural unit (3a)", and the structural unit represented by Formula (3b) is also called "structural unit (3b)."

In the optical film of the present invention comprising a polyamide-based resin having a weight average molecular weight of 200,000 to 1,000,000 having the structural units (1) and (3) as described above, the elastic modulus is improved and the humidity expansion rate is reduced. Although the reason is not clear, in the skeleton of the polyamide-based resin having a predetermined weight average molecular weight, Ar ¹ in the formula (1) is a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms, It is considered that a specific portion in the skeleton of the polyamide-based resin has moderate rigidity. And it is considered that polyamide-type resin will have an intermolecular repulsive force by further having a structural unit (3a) and/or a structural unit (3b). As a result, surprisingly, it is considered that both the improvement of the elastic modulus and the reduction of the humidity expansion rate of the optical film containing such a polyamide-type resin are achieved. The humidity expansion rate is an index indicating the degree of expansion in the planar direction of the optical film under a load, and it has become clear that the molecular structure of the polyamide-based resin constituting the optical film has a large influence on the humidity expansion rate. And it became clear that it may be difficult to make the high elastic modulus of an optical film and the low humidity expansion coefficient compatible only by increasing the structure which has a halogen atom only. In the present invention, a polyamide-based resin having at least a structural unit (1) containing a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms, and a structural unit (3), and having a weight average molecular weight within a predetermined range. It discovered that the optical film which has both a high elastic modulus and low-humidity expansion coefficient by the optical film containing was obtained.

The polyamide-type resin contained in the optical film of this invention has a structural unit (1) and a structural unit (3). From a viewpoint of being easy to raise the elasticity modulus of an optical film, and being easy to reduce a humidity expansion rate, when the sum total of the structural unit (1) and structural unit (3) contained in polyamide-type resin is 100 mol%, structural unit (1) Preferably, it is 10-99 mol%, More preferably, it is 20-95 mol%, More preferably, it is 30-90 mol%, Especially preferably, it is 40-85 mol%. When the ratio of the structural unit (1) is more than the said minimum, it is easy to raise the elasticity modulus of an optical film, and it is easy to reduce a humidity expansion coefficient. Moreover, when the ratio of the structural unit (1) is below the said upper limit, it is easy to ensure the solubility with respect to a solvent. In addition, content of structural unit (1) and structural unit (3) ^{can be measured using 1} H-NMR, for example, or can also be computed from the introduction ratio of a raw material.

Structural unit (1) and structural unit contained in polyamide-type resin in one preferable aspect of this invention in which the polyamide-type resin contained in the optical film of this invention has a structural unit (1) and a structural unit (3a) When the total of (3a) is 100 mol%, the proportion of the structural unit (1) is preferably 10 to 99 mol%, more preferably from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. Preferably it is 20-95 mol%, More preferably, it is 30-90 mol%, Especially preferably, it is 40-85 mol%. When the ratio of the structural unit (1) is more than the said minimum, it is easy to raise the elasticity modulus of an optical film, and it is easy to reduce a humidity expansion coefficient. Moreover, when the ratio of the structural unit (1) is below the said upper limit, it is easy to ensure the solubility with respect to a solvent.

Structural unit (1) and structural unit contained in polyamide-type resin in one preferable aspect of this invention in which the polyamide-type resin contained in the optical film of this invention has a structural unit (1) and a structural unit (3b) When the total of (3b) is 100 mol%, the proportion of the structural unit (1) is preferably 10 to 99 mol%, more preferably from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. Preferably it is 20-95 mol%, More preferably, it is 30-90 mol%, Especially preferably, it is 40-85 mol%. When the ratio of the structural unit (1) is more than the said minimum, it is easy to raise the elasticity modulus of an optical film, and it is easy to reduce a humidity expansion coefficient. Moreover, when the ratio of the structural unit (1) is below the said upper limit, it is easy to ensure the solubility with respect to a solvent. In addition, the content of the structural unit (3a) and the structural unit (3b) ^{can also be measured using, for example, 1} H-NMR, or can be calculated from the introduction ratio of the raw material.

^{Ar 1} in formula (1) represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms. In the present specification, the divalent aromatic group is a group in which two hydrogen atoms of a monocyclic aromatic ring, a condensed polycyclic aromatic ring, or a ring aggregated aromatic ring are substituted with a bond. The divalent aromatic group may include an aromatic ring in which a ring (monocyclic, condensed polycyclic or ring set) is formed only by carbon atoms, or may include a heteroaromatic ring in which a ring is formed including atoms other than carbon atoms. As atoms other than a carbon atom, a nitrogen atom, a sulfur atom, and an oxygen atom are mentioned, for example. Although the total number of the carbon atoms which form an aromatic ring and atoms other than a carbon atom is not specifically limited, Preferably it is 5-18, More preferably, it is 5-14, More preferably, it is 5-12.

Examples of the monocyclic aromatic ring include benzene, furan, pyrrole, thiophene, pyridine, imidazole, pyrazole, oxazole, thiazole and imidazoline.

Examples of the condensed polycyclic aromatic ring include naphthalene, anthracene, phenanthrene, indole, benzothiazole, benzimidazole and benzoxazole.

Examples of the ring aggregated aromatic ring include a structure in which two or more monocyclic aromatic rings and/or condensed polycyclic aromatic rings are connected by a single bond, and examples of the ring described above as examples of monocyclic aromatic rings or condensed polycyclic aromatic rings include: Groups in which two or more are connected by a single bond, for example, biphenyl, terphenyl, quaterphenyl, binaphthyl, 1-phenylnaphthalene, 2-phenylnaphthalene, bipyridine, and the like are exemplified.

From the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate, the divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms is preferably two aromatic hydrocarbon rings having a fluoroalkyl group having 1 to 12 carbon atoms. A group in which a hydrogen atom is substituted by a bond, more preferably a group in which two hydrogen atoms of benzene, biphenyl, terphenyl or quaterphenyl having a fluoroalkyl group having 1 to 12 carbon atoms are substituted by a bond, more preferably having a carbon number It is a group in which two hydrogen atoms of benzene or biphenyl having a fluoroalkyl group of 1 to 12 are substituted with a bond.

^{The fluoroalkyl group having 1 to 12 carbon atoms in Ar 1} in the formula (1) is a group in which at least one hydrogen atom in a linear or branched alkyl group having 1 to 12 carbon atoms is substituted with a fluorine atom. Examples of the linear or branched fluoroalkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group , 2-methyl-butyl group, 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group and n-decyl group The group in which at least 1 hydrogen atom in etc. was substituted by the fluorine atom is mentioned. Specific examples of the fluoroalkyl group having 1 to 12 carbon atoms include, for example, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a fluoroethyl group, a difluoroethyl group, a trifluoroethyl group, a pentafluoroethyl group, A heptafluoropropyl group, a nonafluorobutyl group, etc. are mentioned. The carbon number of the fluoroalkyl group is preferably 1 to 6, more preferably 1 to 4, still more preferably 1 or 2.

The fluoroalkyl group having 1 to 12 carbon atoms is preferably a perfluoroalkyl group having 1 to 12 carbon atoms, more preferably purple having 1 to 6 carbon atoms, from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. A luoroalkyl group, more preferably a perfluoroalkyl group having 1 to 4 carbon atoms, particularly preferably a trifluoromethyl group or a pentafluoroethyl group.

^{Ar 1} in formula (1) may have at least one fluoroalkyl group having 1 to 12 carbon atoms, and the number is not particularly limited, but from the viewpoint of easily increasing the elastic modulus of the optical film and easily reducing the humidity expansion coefficient, The number of the fluoroalkyl groups having 1 to 12 carbon atoms in ^{Ar 1 is preferably 1 to 6, more preferably 1 to 4. When Ar 1} in Formula (1) has two or more C1-C12 fluoroalkyl groups, these may mutually be same or different.

^{Ar 1} in Formula (1) may further have another substituent other than a C1-C12 fluoroalkyl group. As another substituent, a C1-C6 alkyl group, a C1-C6 alkoxy group, or a C6-C12 aryl group is mentioned, for example.

In one preferred aspect of the present invention, the structural unit represented by Formula (1) is Ar ¹ from the viewpoint of easily increasing the elastic modulus of the optical film and easily reducing the humidity expansion coefficient, Formula (4):

[Formula 14]

[In formula (4),

R ¹ represents, independently of each other, a fluoroalkyl group having 1 to 12 carbon atoms,

n and k independently represent an integer of 1 to 4, provided that when n and/or k represents an integer of 2 to 4, a plurality of R ¹ may be the same or different from each other,

* indicates a bonding hand]

and a divalent aromatic group represented by When the structural unit (1) contains a divalent aromatic group represented by Formula (4) as ^{Ar 1} , the structural unit (1) includes one or more aromatic groups represented by Formula (4) as ^{Ar 1 .} It may be included, and other aromatic groups which do not correspond to the aromatic group represented by Formula (4) other than the aromatic group represented by Formula (4) may be included which has a fluoroalkyl group.

The polyamide-based resin contained in the optical film of the present invention has at least a structural unit (1) and a structural unit (3) as described above, and the resin is usually a plurality of structural units (1), a plurality of structural units ( 3) and optionally other structural units. In the present specification, when the structural unit (1) ^{includes an aromatic group represented by formula (4) as Ar 1} , in the plurality of structural units (1) of the polyamide-based resin, at least some structural units ( It means that Ar1 in ¹ ) is represented by Formula (4). The above description is also suitable for other similar descriptions in this specification.

As the fluoroalkyl group having 1 to 12 carbon atoms in ^{R 1} , the above description regarding the fluoroalkyl group having 1 to 12 carbon atoms in ^{Ar 1 is similarly suitable, and preferred descriptions are similarly suitable.}

n and k each independently represent the integer of 1-4. n is preferably an integer of 1 or 2, more preferably 1, from the viewpoint of optical properties. From a viewpoint of an elastic modulus, k becomes like this. Preferably it is an integer of 1 or 2, More preferably, it is 1. Here, when n and/or k represents an integer of 2 to 4, two or more R ¹ may be the same as or different from each other, but from the viewpoint of solubility in a solvent, a plurality of R ¹ are the same desirable. It is more preferable that k is 1 and n is 2, or that k is 2 and n is 1 from a viewpoint which it is easy to raise the elasticity modulus of an optical film and is easy to reduce a humidity expansion coefficient.

With respect to the two bonding hands in the formula (4), the positions of each other are not particularly limited, and any of the ortho position, meta position, and para position may be used. In , the binding hands are preferably positioned para to each other.

As a preferable example of the divalent aromatic group represented by Formula (4), R ¹ in Formula (4) represents a C1-C12 perfluoroalkyl group, k is 1 or 2, n is 1 or 2; and/or an aromatic group in which two bonding hands are located at a position para to each other.

In a preferred embodiment of the present invention, the structural unit represented by Formula (1) contained in the polyamide-based resin included in the optical film of the present invention includes a divalent aromatic group represented by Formula (4) as ^{Ar 1 .} In the following, when the total of the structural units represented by Formula (1) contained in the polyamide-based resin is 100 mol%, Ar ¹ in Formula (1) is a divalent aromatic group represented by Formula (4). The ratio is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate, All structural units represented by Formula (1) WHEREIN: The divalent aromatic group represented by Formula (4) may be sufficient as ^Ar<1>.

As a preferable example of the divalent aromatic group represented by Formula (4), Formula (4a) in which the bond in Formula (4) is located in a mutually para position:

[Formula 15]

[In formula (4a), R ³ to ^{R 6} each independently represent a hydrogen atom or a fluoroalkyl group having 1 to 12 carbon atoms, provided ^{that at least one of R 3} to ^{R 6} is fluoro having 1 to 12 carbon atoms represents an alkyl group, k represents an integer of 1 to 4, and * represents a bond]

and an aromatic group represented by . From the viewpoint of easily increasing the elastic modulus of the optical film and easily reducing the humidity expansion coefficient, when k in formula (4a) is 1, ^{at least one of R 3} to ^{R 6} represents a fluoroalkyl group having 1 to 12 carbon atoms, and R ³ preferably at least two of ~R ⁶ represents a fluoroalkyl group having 1 to 12 carbon atoms, more preferably at least R ³ and R ⁵ represents a fluoroalkyl group having 1 to 12 carbon atoms, and the R ³ and R ⁵ carbon atoms It is more preferable that a fluoroalkyl group of 1 to 12 is represented, and R ⁴ and R ^{6 represent a hydrogen atom.} From the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate, when k in formula (4a) is 2, the group on the first benzene ring is R ^{3 to R 36} , and the group on the second benzene ring is R ³ If a ^{'~R 6', R 3 ~R} 6 and R ³ preferably at least two of the '~R ^6' represents a fluoroalkyl group having 1 to 12 carbon atoms, and is close to a single bond to bond the two benzene ring It is more preferable that at least R ⁴ and R ⁶ ′ present in the position represent a fluoroalkyl group having 1 to 12 carbon atoms, R ⁴ and R ⁶ ′ represent a fluoroalkyl group having 1 to 12 carbon atoms, and R ³ , R ⁵ , R ⁶ and R ³ ′ to ^{R 5} ′ more preferably represent a hydrogen atom. As the fluoroalkyl group having 1 to 12 carbon atoms, the above description regarding the fluoroalkyl group having 1 to 12 carbon atoms in ^{Ar 1 is similarly suitable, and preferred descriptions are also suitable.} From a viewpoint that k in Formula (4a) is easy to raise the elasticity modulus of an optical film and is easy to reduce a humidity expansion coefficient, Preferably it is an integer of 1 or 2. From a viewpoint in which k in Formula (4a) is easy to raise the pencil hardness of an optical film, Preferably it is 2.

Equation (3) represents a Z ¹ of Ar ^1, formula (1) in the above description of the Ar ¹ is, as is suitable for Z ¹ in the formula (3). In addition, the above description regarding ^{Ar 1} in Formula (1) is similarly suitable for ^{Ar 3 in Formula (3b).}

^{When Z 1} in the formula (3) represents a divalent organic group other than Ar ^{1 , Z 1} is a divalent organic group that does not correspond to a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms, for example, carbon number C4 to C40 containing a cyclic structure (preferably an alicyclic structure, an aromatic ring structure, a heterocyclic structure) which may be substituted with a 1 to 8 hydrocarbon group or a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms Examples of the divalent organic group include groups not corresponding to the divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms described for Ar ^{1 .} As a C4-C40 divalent organic group containing a cyclic structure, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26) , (27), (28) and (29):

[Formula 16]

Among the bonds of the group represented by , a group in which two non-adjacent bonds are substituted with hydrogen atoms and a group having a thiophene ring structure are exemplified. Also, among these groups,

^{A group in which two non-adjacent bonds in the group represented by Formula (26) wherein W 1} is a single bond or Formula (26') described later are substituted with a hydrogen atom, substituted with a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms ,

Among the bonds of the groups represented by the formulas (28) and (29) or the formulas (28') and (29') to be described later, two of which are not adjacent to each other are substituted with a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms. a group substituted with a hydrogen atom, and

Since the group having a thiophene ring structure substituted with a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms corresponds to the divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms described for ^{Ar 1 , in this embodiment} It does not correspond to ^{Z 1} in Formula (3).

In formulas (20) to (29),

* represents a bond, W ¹ is a single bond, -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C (CF ₃ ) ₂ -, _{-Ar-, -SO 2} -, -CO-, -O-Ar-O-, -Ar-O-Ar-, -Ar-CH ₂ -Ar-, -Ar-C( CH ₃ ) ₂ -Ar- or -Ar-SO ₂ -Ar-. Ar represents an arylene group having 6 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom, and specific examples thereof include a phenylene group.

^{As Z<1>} in Formula (3), as a C4-C40 divalent organic group containing a cyclic structure, Formula (20'), Formula (21'), Formula (22'), Formula (23'), Formula (24'), (25'), (26'), (27'), (28') and (29'):

[Formula 17]

[In Formulas (20') to (29'), W ¹ and * are as defined in Formulas (20) to (29)]

The divalent organic group represented by is more preferable.

In addition to the structural unit represented by Formula (1), polyamide-type resin, and/or Z<^1> in Formula (3) is a structural unit represented by any one of said Formula (20') - Formula (29') In the case where Z ¹ in Formula (3) has a structural unit represented by Formula (7) to be described later, among them, in addition to the structural unit, the following Formula (d1):

[Formula 18]

[In formula (d1), R ^e represents, independently of each other, a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R ^f is R ^e or - Represents C(=O)-*, * indicates a bond]

It is preferable from a viewpoint that it is easy to improve the film-forming property of a varnish, and it is easy to obtain the uniformity of an optical film to further have the structural unit derived from the carboxylic acid represented by.

In R ^e, an alkyl group having 1 to 6 carbon atoms, alkoxy group and aryl group having a carbon number of 6 to 12 of carbon number 1 to 6, respectively, an alkyl group having 1 to 6 carbon atoms in the Ar ² in the formula (5) below, Examples of the alkoxy group having 1 to 6 carbon atoms or the aryl group having 6 to 12 carbon atoms are exemplified. Specifically, as the structural unit (d1) ^{, a structural unit in which both R e} and R ^f are hydrogen atoms (a structural unit derived from a dicarboxylic acid compound), R ^e is both a hydrogen atom, and R ^f is -C (= The structural unit (structural unit derived from a tricarboxylic acid compound) etc. which represent O)-* are mentioned.

The structural unit represented by Formula (3) is Z ¹ , and Formula (7a):

[Formula 19]

[In formula (7a), R ^g and R ^h each independently represent a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, A, s and * is the same as A, s, and * in formula (7), t and u are each independently an integer of 0 to 4, provided that s is an integer of 1 to 4, and when A is not a single bond , R ^g and R ^h may each independently be substituted with a halogen atom]

It is preferable to include a divalent organic group represented by the formula (7):

[Formula 20]

[In formula (7), R ³¹ to ^{R 38} each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms;

A is, independently of each other, a single bond, -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, -S-, -CO- or -N(R ³⁹ )-, wherein R ³⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

s is an integer from 0 to 4,

* represents a bond,

However, when s is an integer of 1 to 4 and A is not a single bond, ^{the hydrogen atoms included in R 31} to ^{R 38} may be independently substituted with halogen atoms]

It is more preferable to include a divalent organic group represented by .

In the formula (7a), the bond of each benzene ring may be bonded to any of the ortho-position, meta-position, or para-position with respect to -A-, and preferably to the meta-position or para-position. . ^{R g} and R ^h in the formula (7a) each independently represent a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. It is preferable that t and u in the formula (7a) are 0, but when t and/or u are 1 or more, R ^g and R ^h preferably represent an alkyl group having 1 to 6 carbon atoms, more preferably 1 carbon atom to 3 alkyl groups. ^{In R g} and R ^h in Formula (7a), as a halogen atom, a C1-C6 alkyl group, a C1-C6 alkoxy group, and a C6-C12 aryl group, respectively, the halogen in Formula (7) Examples of the atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms are exemplified.

t and u in Formula (7a) are mutually independently an integer of 0-4, Preferably it is an integer of 0-2, More preferably, it is 0 or 1, More preferably, it is 0.

In formulas (7) and (7a), A is a single bond, -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, -S-, -CO- or -N(R ³⁹ )-, from the viewpoint of bending resistance of the optical film, preferably -O- or -S- is represented, More preferably, -O- is represented.

In formula (7), R ³¹ , R ³² , R ³³ , R ³⁴ , R ³⁵ , R ³⁶ , R ³⁷ and R ³⁸ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. of an alkoxy group or an aryl group having 6 to 12 carbon atoms. An alkyl group having 1 to 12 carbon atoms, an alkoxy group of 6 to 12 carbon atoms and having 1 to 6 carbon atoms and the aryl group, the formula (5) or an alkoxy group having a carbon number of the alkyl group, having 1 to 6 carbon atoms having 1 to 12 carbon atoms in the Ar ² of Examples of the 6-12 aryl group include those exemplified above. From the viewpoint of the surface hardness and flexibility of the optical film, R ³¹ to ^{R 38} are each independently, preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms , and more preferably a hydrogen atom. Here, when s is an integer of 1 to 4 and A is not a single bond, ^{the hydrogen atoms included in R 31} to ^{R 38} may be each independently substituted with a halogen atom.

R ³⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom. Examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, and 2-methyl group. -Butyl group, 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group, n-decyl group, etc. are mentioned. and these may be substituted with a halogen atom. As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned. Polyamide-based resin WHEREIN: The structural unit represented by Formula (3) may contain one type of divalent organic group represented by Formula (7) or Formula (7a) as ^{Z<1>, Formula (7)} Or two or more types of organic groups represented by Formula (7a) may be included.

In Formulas (7) and (7a), s is an integer in the range of 0-4, and when s is in this range, the bending resistance and elastic modulus of an optical film will become favorable easily. Moreover, in Formula (7) and Formula (7a), s becomes like this. Preferably it is an integer in the range of 0-3, More preferably, it is 0-2, More preferably, it is 0 or 1. When s is in this range, it will be easy to improve the bending resistance and elastic modulus of an optical film.

In the polyamide-based resin contained in the optical film of the present invention, the structural unit represented by Formula (3) is Z ¹ , and Formula (3'):

[Formula 21]

You may have a structural unit represented by In this case, it is easy to improve the surface hardness and bending resistance of an optical film, and it is easy to reduce yellowness (henceforth YI value).

Formula (3) in Z ¹ is the description of the Z ¹ represents a divalent organic group in the case other than Ar ¹ is suitable, like the Z ² in the above formula (3a).

^{X 1} in formula (1) ^{and X 2} in formula (3) represent a divalent organic group, preferably a divalent organic group having 4 to 40 carbon atoms, more preferably 2 having 4 to 40 carbon atoms having a cyclic structure represents an organic group. As a cyclic structure, an alicyclic ring, an aromatic ring, and a heterocyclic structure are mentioned. In the organic group, a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group, and in that case, the hydrocarbon group and the fluorine-substituted hydrocarbon group preferably have 1 to 8 carbon atoms. In one embodiment of the present invention, the structural unit (1) and the structural unit (3) contained in the polyamide-based resin may each ^{contain one type of organic group as X 1} and X ² , and may contain two or more types of organic groups. It may contain an organic group. In this formula (3) X ¹ in the case of Z ¹ represents a Ar ^1, formula (1) X ¹ in the formula (3) are different from each other.

In one preferred aspect of the present invention, the structural unit represented by Formula (1) and the structural unit represented by Formula (3) are easy to increase the elastic modulus of the optical film, and from the viewpoint of easily reducing the humidity expansion coefficient, respectively, X ^{As 1} and X ² , formula (5):

[Formula 22]

[In formula (5), Ar ² represents a divalent aromatic group which may have a substituent,

V is a single bond, -O-, a diphenylmethylene group, a fluorenyl group, a linear, branched or alicyclic divalent hydrocarbon group having 1 to 12 carbon atoms, -SO ₂ -, -S-, -CO- , -PO-, -PO ₂ -, -N(R ^a )- or -Si(R ^b ) ₂ -; , R ^a and R ^b each independently represent a hydrogen atom or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

m represents an integer of 0 to 3,

* indicates a bonding hand]

and a divalent organic group represented by When the structural unit (1) and the structural unit (3) ^{contain a divalent organic group represented by Formula (5) as X 1} and X ² , respectively, the structural unit (1) and the structural unit (3) are, ^{As X 1} and X ² , respectively, one type or two or more types of divalent organic groups represented by Formula (5) may be included. Structural unit (1) and structural unit (3) are X ¹ and X ² , respectively, other than the divalent organic group represented by the formula (5) other than the divalent organic group represented by the formula (5). The divalent organic group may be included.

^{Ar 2} in Formula (5) represents the divalent aromatic group which may have a substituent. The divalent aromatic group is a group in which two hydrogen atoms of a monocyclic aromatic ring, a condensed polycyclic aromatic ring, or a ring set aromatic ring are substituted with a bond, and a monocyclic aromatic ring, a condensed polycyclic aromatic ring or a ring set for ^{Ar 1} Examples and preferred descriptions relating to the aromatic ring are similarly suitable for the monocyclic aromatic ring, the condensed polycyclic aromatic ring, or the ring-set aromatic ring for ^{Ar 2 .} When m in Formula (5) is 1 or more ^{, two or more Ar<2>} may mutually be same or different.

From the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate, the divalent aromatic group which may have a substituent is preferably a group in which two hydrogen atoms of the aromatic hydrocarbon ring which may have a substituent are substituted with a bond, more Preferably, two hydrogen atoms of optionally substituted benzene, biphenyl, terphenyl or quaterphenyl are substituted with a bond, More preferably, two hydrogen atoms of optionally substituted benzene or biphenyl are substituted with a bond is a group substituted with

Examples of the substituent for Ar ² include a halogen group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, or a group in which a hydrogen atom contained therein is substituted with a halogen atom. .

The C1-C12 alkyl group may be a C1-C12 linear or branched alkyl group, Preferably it is a C1-C6 linear or branched alkyl group. Examples of such groups include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, 2-methyl-butyl group, 3- and a methylbutyl group, 2-ethyl-propyl group, n-hexyl group, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group and n-decyl group.

Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butoxy group, an isobutoxy group, a tert-butoxy group, a pentyloxy group, a hexyloxy group, and a cyclohexyloxy group. time, and the like.

Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a biphenyl group.

As a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned.

As ^{the substituent for Ar 2} , a halogen group or an alkyl group having 1 to 12 carbon atoms in which a hydrogen atom may be substituted with a halogen atom is preferable, and a methyl group, a fluoro group, a chloro group or a trifluoromethyl group is more preferable.

V in formula (5) is a single bond, -O-, a diphenylmethylene group, a fluorenyl group, a linear, branched or alicyclic divalent hydrocarbon group having 1 to 12 carbon atoms, -SO ₂ -, -S -, -CO-, -PO-, -PO ₂ -, -N(R ^a )- or -Si(R ^b ) ₂ -. Here, the hydrogen atoms contained in the hydrocarbon group may each independently be substituted with a halogen atom, and R ^a and R ^b are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom. indicates. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, 2-methyl-butyl group , 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group, n-decyl group, etc. are mentioned, and these are It may be substituted with a halogen atom. As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned. V in formula (5) is preferably a single bond, -O- or -S-, more preferably a single bond or -O-, More preferably, it is a single bond.

m in Formula (5) represents the integer of 0-3, it is easy to raise the elastic modulus of an optical film, From a viewpoint of being easy to reduce a humidity expansion rate, Preferably it is 0-2, More preferably, 0 or 1 is more preferable. it is 1.

Structural unit (1) and structural unit (3) contained in the polyamide-based resin contained in the optical film of the present invention are X ¹ and X ² , respectively, containing a divalent organic group represented by Formula (5) In one preferred aspect of the present invention, the total of the structural units (1) and (3) contained in the polyamide-based resin is 100 mol% from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. When , X ¹ in Formula (1) is a divalent organic group represented by Formula (5), and X ² in Formula (3) is a divalent organic group represented by Formula (5) The sum of the structural units The proportion is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, in all the structural units of the structural unit (1) and the structural unit (3). , X ¹ and X ² may be a divalent organic group represented by the formula (5).

In one preferable aspect of this invention, Formula (5) is easy to raise the elastic modulus of an optical film, and from a viewpoint of being easy to reduce a humidity expansion rate, Formula (5a):

[Formula 23]

[In formula (5a), R ² represents a fluoroalkyl group having 1 to 12 carbon atoms,

p and q each independently represent an integer of 1 to 4, provided that when p and/or q represents an integer of 2 to 4, ^{two or} more R 2 may be the same as or different from each other,

* indicates a bonding hand]

is represented by In the formula (5a), V in the formula (5) represents a single bond, Ar ^{2 represents a benzene ring substituted with a fluoroalkyl group (R 2} ) having 1 to 12 carbon atoms, and m is an integer of 0 to 3 It corresponds to the expression representing When the structural unit (1) and the structural unit (3) ^{contain a divalent organic group represented by the formula (5a) as X 1} and X ² , respectively, the structural unit (1) and the structural unit (3) are, ^{As X 1} and X ² , respectively, one type or two or more types of divalent organic groups represented by the formula (5a) may be included. Structural unit (1) and structural unit (3) are, respectively, as X ¹ and X ² , other than the divalent organic group represented by the formula (5a) other than the divalent organic group represented by the formula (5a). The divalent organic group may be included.

^{R 2} in the formula (5a) represents a fluoroalkyl group having 1 to 12 carbon atoms, and as the group, the above description regarding the fluoroalkyl group having 1 to 12 carbon atoms in ^{Ar 1 is similarly suitable, and a preferred description is also} likewise suitable

p and q each independently represent the integer of 1-4. p is an integer of 1 or 2 from a viewpoint of the elasticity modulus of an optical film, and a humidity expansion coefficient, More preferably, p is 2. From a viewpoint of the elasticity modulus of an optical film, and a humidity expansion coefficient, q becomes like this. Preferably it is an integer of 1 or 2, More preferably, it is 1. Here, when p and/or q represents an integer of 2 to 4, ^{two or} more R 2 may be the same as or different from each other, but from the viewpoint of solubility in a solvent, a plurality of R ² are the same desirable.

Regarding the two bonding hands in the formula (5a), the position of each other is not particularly limited, and any of the ortho position, the meta position, and the para position may be used. In , the binding hands are preferably positioned para to each other.

As a preferable example of the divalent aromatic group represented by Formula (5a), R<^2> in Formula (5a) represents a C1-C12 perfluoroalkyl group, p is 2, q is 1 or 2, and/ Alternatively, an aromatic group in which two bonding hands are located at a para position to each other may be mentioned.

Structural unit (1) and structural unit (3) contained in the polyamide-based resin contained in the optical film of the present invention are X ¹ and X ² , respectively, containing a divalent organic group represented by Formula (5a) In one preferred aspect of the present invention, the total of the structural units (1) and (3) contained in the polyamide-based resin is 100 mol% from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. When , X ¹ in Formula (1) is a divalent organic group represented by Formula (5a), and X ² in Formula (3) is a divalent organic group represented by Formula (5a) The sum of the structural units The proportion is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, in all the structural units of the structural unit (1) and the structural unit (3). , X ¹ and X ² may be a divalent organic group represented by the formula (5a).

In one preferable aspect of this invention, Formula (5a) is easy to raise the elasticity modulus of an optical film, and from a viewpoint of being easy to reduce a humidity expansion rate, Formula (5b):

[Formula 24]

[In formula (5b), R ⁷ to ^{R 14} each independently represent a hydrogen atom or a fluoroalkyl group having 1 to 12 carbon atoms, provided ^{that at least one of R 7} to ^{R 14} is fluoro having 1 to 12 carbon atoms It is an alkyl group, and * represents a bond.]

is represented by In addition, formula (5b) corresponds to the formula in which the bond in formula (5a) is mutually located at the para position, and p is an aromatic group of 2. From the viewpoint of easily increasing the elastic modulus of the optical film and easily reducing the humidity expansion rate, in formula (5b), ^{it is preferable that at least two of R 7} to ^{R 14} represent a fluoroalkyl group having 1 to 12 carbon atoms, and at least R ⁸ and R ¹⁴ is more and more preferably represents a fluoroalkyl group having 1 to 12 carbon atoms, and R ⁸ and R ¹⁴ represents a fluoroalkyl group having 1 to 12 carbon atoms, R ^7, R ^9, R ^10, R ^11, R ^12, and More preferably, R ¹³ represents a hydrogen atom. Further, in the above aspect, the fluoroalkyl group having 1 to 12 carbon atoms is preferably a perfluoroalkyl group having 1 to 12 carbon atoms, more preferably a perfluoroalkyl group having 1 to 6 carbon atoms, still more preferably 1 carbon atoms. A perfluoroalkyl group of -4, still more preferably a trifluoromethyl group or a pentafluoroethyl group, particularly preferably a trifluoromethyl group.

Structural unit (1) and structural unit (3) contained in the polyamide-based resin contained in the optical film of the present invention are X ¹ and X ² , respectively, containing a divalent organic group represented by Formula (5b) In one preferred aspect of the present invention, the total of the structural units (1) and (3) contained in the polyamide-based resin is 100 mol% from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. When , X ¹ in Formula (1) is a divalent organic group represented by Formula (5b), and X ² in Formula (3) is a divalent organic group represented by Formula (5b) of the sum of the structural units The proportion is preferably 20 to 100 mol%, more preferably 30 to 100 mol%, still more preferably 40 to 100 mol%, and in all the structural units of the structural unit (1) and the structural unit (3), , X ¹ and X ² may be a divalent organic group represented by the formula (5b).

In one preferred aspect of the present invention, the formula (5b) is the formula (5c):

[Formula 25]

[* in formula (5c) represents a bond]

is represented by In addition, since Formula (5b) is an expression contained in Formula (5a), Formula (5a) may be represented by Formula (5c). In the divalent organic group represented by the formula (5c), R ⁹ and R ¹¹ in the formula (5b) represent a trifluoromethyl group, and R ⁷ , R ⁸ , R ¹⁰ , R ¹² , R ¹³ and R ¹⁴ are hydrogen atoms. It is a group corresponding to the divalent aromatic group which represents. When structural unit (1) and structural unit (3) contain the divalent organic group represented by Formula (5b) or Formula (5c) as ^X<1> and X<^{2>, respectively, structural unit (1) and structural unit} (3) may contain one type, two or more types of divalent organic groups represented by Formula (5b) or Formula (5c) as ^X<1> and X<^{2>, respectively, respectively, Formula (5b) or Formula (5c)} In addition to the divalent organic group shown, the other divalent organic group which does not correspond to the divalent organic group represented by Formula (5b) and Formula (5c) may be included.

The structural unit (1) and the structural unit (3) contained in the polyamide-based resin contained in the optical film of the present invention are X ¹ and X ² , respectively, containing a divalent organic group represented by the formula (5c) In one preferred aspect of the present invention, the total of the structural units (1) and (2) contained in the polyamide-based resin is 100 mol% from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate. When , X ¹ in Formula (1) is a divalent organic group represented by Formula (5c), and X ² in Formula (3) is a divalent organic group represented by Formula (5c) The sum of the structural units The proportion is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, in all the structural units of the structural unit (1) and the structural unit (3). , X ¹ and X ² may be a divalent organic group represented by the formula (5c).

Which is related to the X ¹ in the formula (1) described above is suitable similarly to X ⁴ and X ³ in formula (3b) in the formula (3a). However, X ⁴ is a divalent organic group other than ^{X 1 .} Here, in the case that X ¹ is two or more, and the one with X ^1, to X ⁴ it may be the other.

The polyamide-based resin contained in the optical film of the present invention is, in addition to the structural unit (1) and the structural unit (3), formula (2):

[Formula 26]

[In formula (2), X represents a divalent organic group, Y represents a tetravalent organic group]

The structural unit represented by (hereinafter, also referred to as "structural unit (2)") may be included. In this case, the polyamide-based resin is a resin also called polyamideimide resin. This aspect WHEREIN: From a viewpoint that it is easy to raise the elasticity modulus of an optical film and it is easy to reduce a humidity expansion rate, the sum total of structural unit (1), structural unit (2), and structural unit (3) contained in polyamide-type resin is 100 When it is set as mol%, the ratio of the total of structural unit (1) and structural unit (2) becomes like this. Preferably it is 60 mol% or more, More preferably, it is 70 mol% or more, More preferably, it is 80 mol% or more. More preferably, it is 85 mol% or more, Especially preferably, it is 90 mol% or more. The upper limit of the said ratio of the total of a structural unit (1) and a structural unit (2) should just be less than 100 mol%. In addition, content of structural unit (1), structural unit (2), or structural unit (3) ^{can be measured using 1} H-NMR, for example, or can also be computed from the introduction ratio of a raw material.

Y in the structural unit represented by formula (2) represents a tetravalent organic group, preferably represents a C4-C40 tetravalent organic group, more preferably a C4-C40 tetravalent organic group having a cyclic structure indicates. As a cyclic structure, an alicyclic ring, an aromatic ring, and a heterocyclic structure are mentioned. The organic group is an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group, and in that case, the hydrocarbon group and the fluorine-substituted hydrocarbon group preferably have 1 to 8 carbon atoms. In one Embodiment of this invention, structural unit (2) may have one type of tetravalent organic group as Y, and may have two or more types of tetravalent organic groups. As Y, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26), Formula (27), Formula (28) and Formula ( 29); a group in which a hydrogen atom in the groups represented by the formulas (20) to (29) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a tetravalent chain hydrocarbon group having 6 or less carbon atoms.

[Formula 27]

In formulas (20) to (29), * represents a bond,

W ¹ is a single bond, -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -Ar ³ -, -SO ₂ -, -CO-, -O-Ar ³ -O-, -Ar ³ -O-Ar ³ -, -Ar ³ -CH ₂ -Ar ³ -, -Ar ³ -C( CH ₃ ) ₂ -Ar ³ - or -Ar ³ -SO ₂ -Ar ³ -. Ar ³ represents an arylene group having 6 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom, and specific examples thereof include a phenylene group. When two or more Ar ³ exist, Ar ³ may be the same as or different from each other.

Among the groups represented by formulas (20) to (29), groups represented by formulas (26), (28) or (29) are preferable from the viewpoint of the elastic modulus, surface hardness, and bending resistance of the optical film, The group represented by Formula (26) is more preferable. In addition, W ¹ _{is, independently of each other, a single bond, -O-, -CH 2} -, -CH ₂ -CH, from the viewpoint of easily increasing the elastic modulus, surface hardness, and bending resistance of the optical film and reducing the YI value. ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ - are preferably single bonds, -O-, -CH ₂ -, -CH(CH _{3 )} )-, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ - are more preferred, and single bond, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ - is more preferred. do.

In one preferred embodiment of the present invention, the structural unit represented by Formula (2) is Y, and Formula (6):

[Formula 28]

[In formula (6), R ¹⁸ to ^{R 25} each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, and R ¹⁸ to ^{R 25} The hydrogen atoms contained in may be each independently substituted with a halogen atom,

* indicates a bonding hand]

and a tetravalent organic group represented by When structural unit (2) contains the tetravalent organic group represented by Formula (6) as Y, it is easy to raise the elastic modulus of an optical film, and it is easy to reduce a humidity expansion coefficient. Moreover, in this case, the solubility to the solvent of polyamide-type resin is improved, it is easy to reduce the viscosity of the varnish containing the said resin, and it is easy to improve the workability of an optical film. Moreover, it is easy to improve the optical characteristic of an optical film.

In formula (6), R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ each independently represent a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. an alkoxy group or an aryl group having 6 to 12 carbon atoms. Alkyl group having 1 to 6 carbon atoms, an alkoxy group of 6 to 12 carbon atoms and having 1 to 6 carbon atoms and the aryl group, the formula (5) or an alkoxy group having a carbon number of the alkyl group, having 1 to 6 carbon atoms having 1 to 12 carbon atoms in the Ar ² of Examples of the 6-12 aryl group include those exemplified above. R ¹⁸ to ^{R 25} each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, where R ¹⁸ to ^{R 25} The contained hydrogen atoms may be each independently substituted with a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R ¹⁸ to ^{R 25} are, independently of each other, easy to increase the elastic modulus of the optical film, easy to reduce the humidity expansion rate, and more preferably a hydrogen atom, from the viewpoint of easily improving surface hardness, bending resistance and transparency; a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, more preferably R ¹⁸ , R ¹⁹ , R ²⁰ , R ²³ , R ²⁴ and R ²⁵ are hydrogen atoms, R ²¹ and R ²² are hydrogen atoms; a methyl group, a fluoro group, a chloro group, or a trifluoromethyl group, particularly preferably R ²¹ and R ²² are a methyl group or a trifluoromethyl group.

In one preferred aspect of the present invention, the structural unit (2) contained in the polyamide-based resin contained in the optical film of the present invention contains, as Y, a tetravalent organic group represented by the formula (6). From the viewpoint of easily increasing the elastic modulus and reducing the humidity expansion rate, when the total of the structural units (2) contained in the polyamide-based resin is 100 mol%, Y in the formula (2) is represented by the formula (6) The ratio of the structural unit which is a tetravalent organic group becomes like this. Preferably it is 70-100 mol%, More preferably, it is 80-100 mol%, More preferably, it is 90-100 mol%, In all the structural units of structural unit (2) In this case, Y may be a tetravalent organic group represented by Formula (6).

In one preferred embodiment of the present invention, the formula (6) is the formula (6a):

[Formula 29]

is represented by In addition, the formula (6a) corresponds to the formula in which R ²¹ and R ²² in the formula (6) are trifluoromethyl groups, and R ¹⁸ , R ¹⁹ , R ²⁰ , R ²³ , R ²⁴ and R ²⁵ are hydrogen atoms. . When the structural unit (2) contains the tetravalent organic group represented by Formula (6a) as Y, it is easy to raise the elastic modulus of an optical film, and it is easy to reduce a humidity expansion coefficient. Moreover, in this case, the solubility to the solvent of polyamide-type resin is improved, it is easy to reduce the viscosity of the varnish containing the said resin, and it is easy to improve the workability of an optical film. Moreover, it is easy to improve the optical characteristic of an optical film.

In one preferred aspect of the present invention, the structural unit (2) contained in the polyamide-based resin contained in the optical film of the present invention contains, as Y, a tetravalent organic group represented by the formula (6a). From the viewpoint of easily increasing the elastic modulus and reducing the humidity expansion rate, when the total of the structural units (2) contained in the polyamide-based resin is 100 mol%, Y in the formula (2) is represented by the formula (6a) The ratio of the structural unit which is a tetravalent organic group becomes like this. Preferably it is 70-100 mol%, More preferably, it is 80-100 mol%, More preferably, it is 90-100 mol%, In all the structural units of structural unit (2) In this case, Y may be a tetravalent organic group represented by the formula (6a).

Polyamide-type resin may contain the structural unit represented by Formula (30) and/or the structural unit represented by Formula (31) other than the structural unit represented by Formula (1) and Formula (2).

[Formula 30]

In the formula (30), Y ¹ is a tetravalent organic group, preferably an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. As Y<^1> , the group described as Y in Formula (2) is mentioned. In one embodiment of the present invention, the polyamide-based resin may include a plurality of types of Y ^1, Y ¹ of a plurality of species, and may be same or different from each other.

In the formula (31), Y ² is a trivalent organic group, preferably an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. Examples of Y ² include a group in which any one of the bonds of the group described as Y in the formula (2) is substituted with a hydrogen atom, and a trivalent chain hydrocarbon group having 6 or less carbon atoms. In one embodiment of the present invention, the polyamide-based resin may include a plurality of types of Y ^2, Y ² is a plurality of types, and may be same or different from each other.

In Formulas (30) and (31), X ¹ and X ² each independently represent a divalent organic group, Preferably, a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. it is a device As X ¹ and X ² , groups described as ^{X 1} and X ² in formulas (1) and (2) are exemplified.

In one embodiment of the present invention, the polyamide-based resin comprises a structural unit represented by Formula (1), a structural unit represented by Formula (2), and optionally a structural unit represented by Formula (3); It consists of a structural unit represented by Formula (30), and/or a structural unit represented by Formula (31). From the viewpoint of easy to increase the elastic modulus of the optical film, easy to reduce the humidity expansion rate, and easy to improve optical properties, surface hardness and flex resistance, in the polyamide-based resin, it is represented by formulas (1) and (2) Based on the total structural units represented by the formulas (1) and (2), and optionally by the formulas (3), (30) and (31), preferably 80 mol% or more , More preferably, it is 90 mol% or more, More preferably, it is 95 mol% or more. In addition, in polyamide-type resin, the structural unit represented by Formula (1) and Formula (2) is Formula (1) and Formula (2), and in some cases Formulas (3), Formula (30) and/ Or based on the total structural unit represented by Formula (31), it is 100 % or less normally. In addition, the said ratio ^{can be measured using 1} H-NMR, for example, or can also be computed from the introduction ratio of a raw material.

In one embodiment of the present invention, the content of the polyamide-based resin in the optical film is preferably 10 parts by mass or more, more preferably 30 parts by mass or more, still more preferably 10 parts by mass or more with respect to 100 parts by mass of the optical film. is 50 parts by mass or more, preferably 99.5 parts by mass or less, more preferably 95 parts by mass or less. When content of polyamide-type resin is in the said range, it will be easy to raise the optical characteristic and elastic modulus of an optical film, and it will be easy to reduce a humidity expansion coefficient.

The weight average molecular weight (Mw) of the polyamide-based resin is 200,000 to 1,000,000 in terms of standard polystyrene. When the weight average molecular weight (Mw) of the polyamide-based resin is less than 200,000, the elastic modulus of the optical film cannot be sufficiently increased and the humidity expansion coefficient cannot be sufficiently reduced. Moreover, when the weight average molecular weight (Mw) of polyamide-type resin exceeds 1,000,000, the solubility to the solvent of polyamide-type resin falls, and it becomes difficult to process an optical film. The weight average molecular weight (Mw) of the polyamide-based resin, in terms of standard polystyrene, is preferably 220,000 from the viewpoint of easily increasing the elastic modulus, surface hardness and bending resistance of the optical film and reducing the humidity expansion coefficient of the optical film. or more, more preferably 250,000 or more, still more preferably 270,000 or more, particularly preferably 300,000 or more. In addition, from the viewpoint of easily improving the solubility of the polyamide-based resin in a solvent and improving the stretchability and workability of the optical film, the weight average molecular weight of the resin is preferably 900,000 or less, more preferably 800,000 or less, more preferably 700,000 or less, particularly preferably 600,000 or less. A weight average molecular weight can perform a GPC measurement, for example, can be calculated|required by standard polystyrene conversion, for example, may be computed by the method as described in an Example.

The elastic modulus of the optical film of the present invention is preferably 4 GPa or more, more preferably 4.5 GPa or more, still more preferably 4.8 GPa or more, and is usually 100 GPa or less from the viewpoint of easily preventing damage to the optical film. In addition, the elastic modulus can be measured using a tensile tester (50 mm distance between chuck|zippers, 10 mm/min of tensile speed), for example, can be measured by the method as described in an Example.

The humidity expansion coefficient (hereinafter, sometimes referred to as CME) of the optical film of the present invention is from a viewpoint that it is easy to suppress the expansion and contraction of the optical film in the planar direction when the temperature and humidity change in a state in which a load is applied to the optical film. , preferably 23 ppm or less, more preferably 22 ppm or less, still more preferably 21 ppm or less, particularly preferably 20 ppm or less. The smaller the humidity expansion coefficient, the easier it is to suppress the expansion and contraction of the optical film in the planar direction when the temperature and humidity change under a load on the optical film, and the lower limit is not particularly limited, and may be 0 ppm or more . In addition, CME may be the humidity expansion rate of the film when it controls at 60 degreeC and 90 %R.H., and hold|maintains for 1 hour, for example, can be measured by the method as described in an Example.

The total light transmittance of the optical film of the present invention and/or the light transmittance for light of 300 to 800 nm is preferably 80% or more, more preferably 85% or more, still more preferably 90% or more, particularly preferably is 91% or more, and is usually 100% or less. When a total light transmittance is more than the said lower limit, when an optical film is installed in a display apparatus especially as a front plate, it will be easy to improve visibility. Since the optical film of this invention usually shows high total light transmittance, for example, compared with the case where the low transmittance|permeability film is used, it becomes possible to suppress the light emission intensity of the display element etc. which are required for obtaining constant brightness. For this reason, power consumption can be reduced. For example, when the optical film of the present invention is provided in a display device, bright display tends to be obtained even if the amount of light of the backlight is reduced, which can contribute to energy saving. In addition, total light transmittance can be measured using a haze computer based on JISK7361-1:1997, for example. Total light transmittance in the range of the thickness of the optical film mentioned later may be sufficient as total light transmittance.

The haze of the optical film of the present invention is preferably 5% or less, more preferably 4% or less, still more preferably 3% or less, still more preferably 2.5% or less, particularly preferably 2% or less, particularly More preferably, it is 1 % or less, Especially more preferably, it is 0.5 % or less, Especially preferably, it is 0.2 % or less, Usually, it is 0.01 % or more. When the haze of an optical film is below the said upper limit, when an optical film is installed in a display apparatus especially as a front plate, it will be easy to improve visibility. In addition, a haze can be measured using a haze computer based on JISK7136:2000.

YI value of the optical film of this invention becomes like this. Preferably it is 3.5 or less, More preferably, it is 3.0 or less, More preferably, it is 2.5 or less, Usually -5 or more, Preferably it is -2 or more. When transparency becomes favorable as YI value of an optical film is below the said upper limit and it uses for the front plate of a display device, it can contribute to high visibility. In addition, the YI value is measured for transmittance of 300-800 nm light using an ultraviolet visible near-infrared spectrophotometer to obtain tristimulus values (X, Y, Z), and YI = 100 × (1.2769X-1.0592Z). )/Y can be calculated based on the formula. In addition, in this specification, that an optical film is excellent in an optical characteristic means that the light transmittance is high.

The thickness of the optical film of the present invention is preferably 10 µm or more, more preferably 20 µm or more, still more preferably 25 µm or more, particularly preferably 30 µm or more, preferably 200 µm or less, more preferably Preferably it is 100 micrometers or less, More preferably, it is 80 micrometers or less, Especially preferably, it is 60 micrometers or less, A combination of these upper and lower limits may be sufficient. When the thickness of an optical film exists in said range, it will be easy to raise the elasticity modulus of an optical film more. In addition, the thickness of an optical film can be measured using a micrometer, for example, can be measured by the method as described in an Example.

In the optical film of the present invention, the number of bending times (bending radius R = 1 mm) in the bending resistance test is preferably 150,000 times or more, more preferably 180,000 times or more, still more preferably 200,000 times or more. . It has bending resistance sufficient as a front-plate material, such as a flexible display device, as the number of times of bending is more than the said lower limit. In addition, the number of bending in the bending resistance test is performed repeatedly bending of an optical film under the conditions of a bending radius (radius of curvature) (R) of 1 mm using a bending tester, until the time of cracking in the said film Shows the number of reciprocating bending times (1 reciprocating is 1).

The pencil hardness of at least one surface of the optical film of this invention becomes like this. Preferably it is HB or more, More preferably, it is F or more. When the pencil hardness of the at least one surface of an optical film is more than said hardness, it is easy to prevent the damage|wound etc. in the said surface of an optical film. In addition, pencil hardness can be measured based on JISK5600-5-4:1999, for example, can be measured by the method as described in an Example.

In addition to the optical film containing the polyamide-based resin, the present invention also provides the above-mentioned polyamide-based resin suitable for producing the optical film. Such polyamide-based resin is, for example, formula (1):

[Formula 31]

[In formula (1), Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,

X ¹ represents a divalent organic group]

^{, and as Ar 1} in Formula (1), Formula (4):

[Formula 32]

[In formula (4), R ¹ represents a fluoroalkyl group having 1 to 12 carbon atoms,

n and k independently represent an integer of 1 to 4, provided that when n and/or k represents an integer of 2 to 4, a plurality of R ¹ may be the same or different from each other,

* indicates a bond]

A structural unit containing an aromatic group represented by, and Formula (3):

[Formula 33]

Equation (3) of the, Z ¹ is represented by Ar ^1, or Ar 2 represents ^one divalent organic group other than, and as defined by Ar ¹ is in the formula (1),

X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;

A polyamide-based resin having at least a structural unit represented by , and having a weight average molecular weight of 200,000 to 1,000,000 may be used. Regarding examples and preferred embodiments of the types of symbols and ratios of structural units in the polyamide-based resin, the above description of the polyamide-based resin contained in the optical film of the present invention is similarly suitable.

The content of halogen atoms in the polyamide-based resin is preferably 1 to 60% by mass, more preferably 5 to 55% by mass, still more preferably 10 to 50% by mass based on the mass of the polyamide-based resin. mass %. It is easy to raise the elasticity modulus of an optical film as content of a halogen atom is more than the said minimum, and it is easy to reduce a humidity expansion rate, and it is easy to improve transparency and visibility more easily. If content of a halogen atom is below the said upper limit, it will become easy to synthesize|combine resin.

When the polyamide-based resin of the present invention is a polyamideimide resin having the structural unit (2), the imidization ratio of the resin is preferably 90% or more, more preferably 93% or more, and still more preferably 96% or more, and usually 100% or less. From a viewpoint of being easy to improve the optical characteristic of an optical film, it is preferable that imidation ratio is more than said lower limit. The imidation ratio represents the ratio of the molar amount of the imide bond in the polyamide-based resin to a value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamide-based resin. In addition, when the polyamide-based resin contains a tricarboxylic acid compound, a value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamide-based resin and the structural unit derived from the tricarboxylic acid compound The ratio of the molar amount of the imide bond in the polyamide-based resin to the total molar amount is shown. In addition, the imidation ratio can be calculated|required by IR method, NMR method, etc.

<Method for producing resin>

Polyamide-type resin can be manufactured using, for example, a dicarboxylic acid compound and a diamine compound as main raw materials. Here, the structural unit represented by said Formula (1) and Formula (3) is a structural unit formed by a dicarboxylic acid compound and a diamine compound reacting. Therefore, you may manufacture polyamide-type resin using the dicarboxylic acid compound and diamine compound used as the structural unit represented by said Formula (1) and Formula (3).

In addition, the structural unit represented by said Formula (2) which polyamide-type resin of this invention has arbitrarily is a structural unit formed by reacting a tetracarboxylic acid compound and a diamine compound. Therefore, in this case, you may manufacture polyamide-type resin further using the tetracarboxylic-acid compound and diamine compound used as a structural unit represented by said Formula (2).

It is preferable that a dicarboxylic acid compound contains the compound represented by Formula (8) at least from this viewpoint.

[Formula 34]

[In formula (8), Ar ¹ is as defined for ^{Ar 1} in formula (1),

R ^c and R ^d are, independently of each other, a hydroxyl group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group or a chlorine atom indicate.]

In one preferred embodiment of the present invention, the dicarboxylic acid compound is a compound represented by formula (8), wherein ^{R c} and R ^{d are chlorine atoms.} Moreover, you may use a diisocyanate compound instead of a diamine compound.

The dicarboxylic acid compound used in the production of the resin is preferably an aromatic dicarboxylic acid having a fluoroalkyl group or an acid chloride compound thereof, such as terephthalic acid having a fluoroalkyl group, 4,4'-oxybisbenzoic acid, or their Acid chloride compounds are used. In addition to terephthalic acid, 4,4'-oxybisbenzoic acid, or their acid chloride compounds, other dicarboxylic acid compounds may be used. As another dicarboxylic acid compound, an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, the acid chloride compound of those, acid anhydride, etc. are mentioned, You may use in combination of 2 or more type. Specific examples include an aromatic dicarboxylic acid compound having a trifluoromethyl group (isophthalic acid; naphthalenedicarboxylic acid; 4,4'-biphenyldicarboxylic acid; 3,3'-biphenyldicarboxylic acid), and trifluoro A compound in which two benzoic acids having a romethyl group are linked by a single bond or a phenylene group, and their acid chloride compounds are exemplified. As specific examples, 2,2'-bis(trifluoromethyl)-4,4'-biphenyldicarboxylic acid chloride and 2,5-bis(trifluoromethyl)terephthaloyl chloride are preferable.

As a dicarboxylic acid compound, you may use the compound represented by Formula (8), and another dicarboxylic acid compound. As another dicarboxylic acid compound, Formula (7')

[Formula 35]

[In formula (7'), R ³¹ to ^{R 38} independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R ³¹ to The ^{hydrogen atoms contained in R 38} may be each independently substituted with a halogen atom,

A is a single bond, -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, - SO ₂ -, -S-, -CO- or -N(R ³⁹ )- represents,

R ³⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

s is an integer from 0 to 4,

R ^c and R ^d are as defined for ^{R c} and R ^d in formula (8)]

The dicarboxylic acid compound represented by is mentioned.

In one embodiment of the present invention, the other dicarboxylic acid compound may be a compound represented by formula (7') in which s is 1-4 and A is an oxygen atom.

As a diamine compound used for manufacture of resin, an aliphatic diamine, an aromatic diamine, and these mixtures are mentioned, for example. In addition, in this embodiment, "aromatic diamine" represents the diamine in which the amino group is couple|bonded directly with the aromatic ring, and may contain the aliphatic group or another substituent in a part of the structure. This aromatic ring may be a monocyclic ring or a condensed ring may be sufficient as it, Although a benzene ring, a naphthalene ring, an anthracene ring, a fluorene ring, etc. are illustrated, It is not limited to these. Among these, a benzene ring is preferable. In addition, "aliphatic diamine" represents the diamine in which the amino group is couple|bonded directly with the aliphatic group, and may contain the aromatic ring and another substituent in a part of the structure.

Examples of the aliphatic diamine include acyclic aliphatic diamines such as hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, norbornanediamine and 4; Cyclic aliphatic diamines, such as 4'- diamino dicyclohexyl methane, etc. are mentioned. These can be used individually or in combination of 2 or more types.

Examples of the aromatic diamine include p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene, 2, Aromatic diamines having one aromatic ring, such as 6-diaminonaphthalene, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 3,3'-dia minodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[ 4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]propane , 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl (sometimes referred to as TFMB), 4,4'-bis(4- Aminophenoxy)biphenyl, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis(4-amino-3-methylphenyl)fluorene, 9,9-bis(4-amino-3- and aromatic diamines having two or more aromatic rings, such as chlorophenyl)fluorene and 9,9-bis(4-amino-3-fluorophenyl)fluorene. These can be used individually or in combination of 2 or more types.

Aromatic diamine is preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylether, 3,3'-diaminodiphenylether , 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl] Sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy) ) Phenyl] propane, 2,2'-dimethylbenzidine, 2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl (TFMB), 4,4'-bis (4-aminophenoxy) c) biphenyl, more preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 4,4'-diamino Diphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl] Propane, 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl (TFMB), 4,4'-bis(4-aminophenoxy) ratio It is phenyl. These can be used individually or in combination of 2 or more types.

Among the above diamine compounds, it is preferable to use at least one selected from the group consisting of aromatic diamines having a biphenyl structure from the viewpoint of high surface hardness, high transparency, high flexibility, high bending resistance and low coloration of the optical film. 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)benzidine, 4,4'-bis(4-aminophenoxy)biphenyl and 4,4'-diaminodiphenyl ether It is more preferable to use at least one selected from the group consisting of 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl (TFMB).

When using a tetracarboxylic-acid compound for manufacture of resin, As a tetracarboxylic-acid compound, Aromatic tetracarboxylic-acid compounds, such as aromatic tetracarboxylic dianhydride; and aliphatic tetracarboxylic acid compounds such as aliphatic tetracarboxylic dianhydride. A tetracarboxylic acid compound may be used independently and may be used in combination of 2 or more type. The tetracarboxylic acid compound may be a tetracarboxylic acid compound analog other than a dianhydride, such as an acid chloride compound.

Specific examples of the aromatic tetracarboxylic dianhydride include non-condensed polycyclic aromatic tetracarboxylic dianhydride, monocyclic aromatic tetracarboxylic dianhydride, and condensed polycyclic aromatic tetracarboxylic dianhydride. Examples of the non-condensed polycyclic aromatic tetracarboxylic dianhydride include 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2', 3,3'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3 ,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl) Propane dianhydride, 2,2-bis(3,4-dicarboxyphenoxyphenyl)propane dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (sometimes described as 6FDA) , 1,2-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,2-bis(3,4-dicarboxyphenyl) ) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride , 4,4'-(p-phenylenedioxy)diphthalic dianhydride and 4,4'-(m-phenylenedioxy)diphthalic dianhydride. Examples of the monocyclic aromatic tetracarboxylic dianhydride include 1,2,4,5-benzenetetracarboxylic dianhydride, and examples of the condensed polycyclic aromatic tetracarboxylic dianhydride include, 2,3,6,7-naphthalenetetracarboxylic dianhydride is mentioned.

Among these, preferably 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, and 2,2',3,3'-benzophenonetetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-di Phenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2-bis( 3,4-dicarboxyphenoxyphenyl)propane dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA), 1,2-bis(2,3-dicarboxyphenyl)ethane Dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,2-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-di) Carboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, 4,4'-(p-phenylenedioxy)diphthalic dianhydride water and 4,4'-(m-phenylenedioxy)diphthalic dianhydride, more preferably 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-biphenyl Tetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA), bis(3,4) -dicarboxyphenyl)methane dianhydride and 4,4'-(p-phenylenedioxy)diphthalic acid dianhydride are mentioned. These can be used individually or in combination of 2 or more types.

Examples of the aliphatic tetracarboxylic dianhydride include cyclic or acyclic aliphatic tetracarboxylic dianhydride. Cyclic aliphatic tetracarboxylic dianhydride is tetracarboxylic dianhydride having an alicyclic hydrocarbon structure, and specific examples thereof include 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4- Cycloalkanetetracarboxylic dianhydride such as cyclobutanetetracarboxylic dianhydride and 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3; and 5,6-tetracarboxylic dianhydride, dicyclohexyl-3,3',4,4'-tetracarboxylic dianhydride, and positional isomers thereof. These can be used individually or in combination of 2 or more types. Specific examples of the acyclic aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride, and the like. Or it can use in combination of 2 or more types. Moreover, you may use combining cyclic aliphatic tetracarboxylic dianhydride and acyclic aliphatic tetracarboxylic dianhydride.

Among the tetracarboxylic dianhydrides, 4,4'-oxydiphthalic dianhydride, 3,3',4, from the viewpoint of high surface hardness, high transparency, high flexibility, high bending resistance, and low coloring of the optical film, 4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3 ',4,4'-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride Water, and mixtures thereof, are preferred, 3,3',4,4'-biphenyltetracarboxylic dianhydride and 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride, and mixtures thereof More preferably, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA) is more preferable.

The polyamide-based resin may be obtained by further reacting tetracarboxylic acid and tricarboxylic acid and their anhydrides and derivatives in addition to the tetracarboxylic acid compound within a range that does not impair the various physical properties of the optical laminate.

As tetracarboxylic acid, the water adduct of the anhydride of the said tetracarboxylic acid compound is mentioned.

As a tricarboxylic acid compound, an aromatic tricarboxylic acid, an aliphatic tricarboxylic acid, the acid chloride compound of those, an acid anhydride, etc. are mentioned, You may use in combination of 2 or more type. Specific examples include anhydride of 1,2,4-benzenetricarboxylic acid; 2,3,6-naphthalenetricarboxylic acid-2,3-anhydride; and compounds in which phthalic anhydride and benzoic acid are linked by a single bond, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, or a phenylene group.

In manufacture of resin, the usage-amount of a diamine compound and a dicarboxylic acid compound, and the usage-amount of the tetracarboxylic acid compound used as the case may be suitably selected according to the ratio of each structural unit of a desired polyamide-type resin.

In the production of the resin, the reaction temperature of the diamine compound and the dicarboxylic acid compound and, in some cases, the tetracarboxylic acid compound is not particularly limited, but for example, 5-350°C, preferably 5-200°C, more Preferably it is 5-100 degreeC. Although reaction time is not specifically limited, either, For example, it is about 30 minutes - about 10 hours. If necessary, the reaction may be performed under an inert atmosphere or under reduced pressure. In a preferred embodiment, the reaction is carried out under normal pressure and/or in an inert gas atmosphere while stirring. In addition, it is preferable to perform reaction in the solvent inactive to reaction. The solvent is not particularly limited as long as it does not affect the reaction, and for example, water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy- alcohol solvents such as 2-propanol, 2-butoxyethanol, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, γ-valerolactone, propylene glycol methyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; alicyclic hydrocarbon solvents such as ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; amide solvents such as N,N-dimethylacetamide and N,N-dimethylformamide; sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide, and sulfolane; carbonate solvents such as ethylene carbonate and propylene carbonate; and combinations thereof. Among these, an amide type solvent can be used suitably from a solubility viewpoint.

In the case of producing a polyamide-based resin (polyamideimide-based resin) having a weight average molecular weight of 200,000 to 1,000,000, which further has a structural unit (2) in addition to the structural unit (1) and the structural unit (3), the production method Silver is not particularly limited as long as the above polyamideimide-based resin is obtained, but from the viewpoint of easily increasing the elastic modulus of the optical film and reducing the humidity expansion rate, a diamine compound, a tetracarboxylic acid compound, and a dicarboxylic acid compound are reacted. As the method, it is preferable to prepare a polyamideimide-based resin by a production method in which a dicarboxylic acid compound is added in portions, a step (I) of reacting a diamine compound and a tetracarboxylic acid compound to produce an intermediate (A); and a step (II) of reacting the intermediate (A) with a dicarboxylic acid compound (preferably a compound represented by formula (8)), wherein in the step (II), the dicarboxylic acid compound is It is preferable to manufacture a polyamide-type resin by the method of adding by division.

In the polyamide-based resin contained in the optical film of the present invention, Ar ¹ in the formula (1) is a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms, and thus a specific portion in the skeleton of the polyamide-based resin. This is considered to have moderate rigidity and intermolecular repulsive force. When manufacturing polyamide-type resin which has such a structure without using the method of adding a dicarboxylic acid compound by division, it may become difficult to make the weight average molecular weight of polyamide-type resin into the said range. Moreover, although the reason is not clear by manufacturing using the method of adding by division, it is thought that resin optimal for raising the elastic modulus of an optical film and reducing a humidity expansion rate is obtained.

Therefore, the polyamide-based resin contained in the optical film of the present invention and the polyamide-based resin of the present invention are a manufacturing method in which a diamine compound, a tetracarboxylic acid compound, and a dicarboxylic acid compound are reacted. It is preferable that it is a resin manufactured by the manufacturing method of divided addition, and the process (I) of reacting a diamine compound and a tetracarboxylic acid compound to produce|generate an intermediate (A), and the said intermediate (A) and a dicarboxylic acid compound ( A resin produced by a production method comprising the step (II) of preferably reacting the compound represented by the formula (8)), wherein the dicarboxylic acid compound is added in portions in the step (II). It is more preferable that A step of adding a dicarboxylic acid compound in portions to a polyamideimide-based resin having at least the structural unit (1), the structural unit (2) and the structural unit (3) and having a weight average molecular weight of 200,000 to 1,000,000; When manufacturing by the manufacturing method containing, it is easy to adjust the weight average molecular weight of polyamide-type resin within the said range.

In the case of producing a polyamideimide-based resin by the production method including the above steps (I) and (II), the step (I) of reacting a diamine compound and a tetracarboxylic acid compound to produce an intermediate (A) Although the reaction temperature is not specifically limited, For example, 5-200 degreeC, Preferably it is 5-100 degreeC, More preferably, it is 5-50 degreeC, More preferably, it may be 5 degreeC - room temperature (about 25 degreeC). The reaction time may be, for example, 1 minute to 72 hours, preferably 10 minutes to 24 hours. In addition, the reaction may be carried out while stirring in air or in an atmosphere of an inert gas such as nitrogen or argon, or may be carried out under normal pressure, under pressure, or under reduced pressure. In a preferred embodiment, it is carried out under normal pressure and/or in the inert gas atmosphere, while stirring.

In the step (I), the diamine compound and the tetracarboxylic acid compound react to produce an intermediate (A), that is, a polyamic acid. Therefore, the intermediate body (A) has at least a structural unit derived from a diamine compound and a structural unit derived from a tetracarboxylic acid compound.

Next, in the step (II), it is preferable to react the intermediate (A) with the dicarboxylic acid compound, and to add the dicarboxylic acid compound in portions. The dicarboxylic acid compound is dividedly added to the reaction solution obtained in the step (I), and the intermediate (A) and the dicarboxylic acid compound are reacted. It is easy to raise the molecular weight of a polyamide-type resin by not adding a dicarboxylic acid compound all at once, but adding it dividedly. In addition, in this specification, divided addition means dividing and adding the dicarboxylic acid compound to be added in several times, more specifically, dividing the dicarboxylic acid to be added into a specific amount, each with a predetermined interval (predetermined time) means to add Since the predetermined interval (predetermined time) includes even a very short interval (or time), the divided addition includes continuous addition (or continuous feed).

Step (II) WHEREIN: The number of times of division|segmentation at the time of dividingly adding a dicarboxylic acid compound can be suitably selected according to the reaction scale, the kind of raw material, etc., Preferably it is 2-20 times, More preferably, it is 3-10 times. , more preferably 3 to 6 times. It is easy to raise the molecular weight of polyamide-type resin as the number of division|segmentation is the said range.

A dicarboxylic acid compound may be divided|segmented and added by the equal quantity, and may be divided|segmented and added by the non-uniform quantity. The time between each addition (it may be referred to as an addition interval) may be the same or different. In addition, when two or more types of dicarboxylic acid compounds are added, the term "partial addition" means adding the total amount of all dicarboxylic acid compounds by dividing, and the method of dividing each dicarboxylic acid compound is not particularly limited. However, for example, each dicarboxylic acid compound may be separately added collectively or dividedly, each dicarboxylic acid compound may be dividedly added together, and these combinations may be sufficient.

In step (II), when the weight average molecular weight of the polyamide-based resin reaches preferably 10% or more, more preferably 15% or more with respect to the weight average molecular weight of the obtained polyamide-based resin, the addition Preferably it is 1-40 mol% with respect to the total molar amount of a dicarboxylic acid compound, It is preferable to add a dicarboxylic acid compound, More preferably, 2-25 mol%.

Although the reaction temperature of step (II) is not specifically limited, For example, 5-200 degreeC, Preferably 5-100 degreeC, More preferably, 5-50 degreeC, More preferably, 5 degreeC - room temperature (25 degreeC) degree) may be sufficient. In addition, the reaction may be carried out while stirring in air or in an atmosphere of an inert gas such as nitrogen or argon, or may be carried out under normal pressure, under pressure, or under reduced pressure. In a preferred embodiment, the step (II) is performed under normal pressure and/or the inert gas atmosphere while stirring.

Step (II) WHEREIN: A polyamideimide precursor is obtained by carrying out stirring etc. and reacting a dicarboxylic acid compound by division|segmentation addition for predetermined time. In addition, the polyamideimide precursor is isolated (for example, by adding a large amount of water to a reaction solution containing the polyamideimide precursor to precipitate the polyamideimide precursor, followed by filtration, concentration, drying, etc.)單離) can

In the step (II), the intermediate (A) and the dicarboxylic acid compound react to obtain a polyamideimide precursor. Therefore, the polyamideimide precursor is a polyamideimide before imidization (before ring closure) having at least a structural unit derived from a diamine compound, a structural unit derived from tetracarboxylic acid, and a structural unit derived from a dicarboxylic acid compound. indicates

In the case of producing the polyamide-based resin further having the structural unit (2), the method for producing the polyamide-based resin further comprises an imidization step (III) of imidizing a polyamideimide precursor in the presence of an imidization catalyst. may contain By subjecting the polyamideimide precursor obtained in the step (II) to the step (III), among the structural units of the polyamideimide precursor, a portion of the structural unit having a polyamic acid structure is imidized (cyclized), and the formula (1) ), a polyamide-based resin comprising a structural unit represented by the formula (2) and a structural unit represented by the formula (3) can be obtained. In an imidation process, imidation can be carried out in presence of an imidation catalyst. Examples of the imidization catalyst include aliphatic amines such as tripropylamine, dibutylpropylamine, and ethyldibutylamine; alicyclic amines (monocyclic) such as N-ethylpiperidine, N-propylpiperidine, N-butylpyrrolidine, N-butylpiperidine, and N-propylhexahydroazepine; alicyclic amines (polycyclic) such as azabicyclo[2.2.1]heptane, azabicyclo[3.2.1]octane, azabicyclo[2.2.2]octane, and azabicyclo[3.2.2]nonane; and pyridine, 2-methylpyridine (2-picoline), 3-methylpyridine (3-picoline), 4-methylpyridine (4-picoline), 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine and aromatic amines such as , 2,4-dimethylpyridine, 2,4,6-trimethylpyridine, 3,4-cyclopentenopyridine, 5,6,7,8-tetrahydroisoquinoline, and isoquinoline. . Moreover, it is preferable to use an acid anhydride with an imidation catalyst from a viewpoint of being easy to accelerate|stimulate imidation reaction. Examples of the acid anhydride include a conventional acid anhydride used in the imidation reaction, and specific examples thereof include aliphatic acid anhydrides such as acetic anhydride, propionic acid anhydride and butyric acid anhydride, and aromatic acid anhydrides such as phthalic acid.

The polyamide-based resin may be isolated by a conventional method, for example, separation means such as filtration, concentration, extraction, crystallization, recrystallization, column chromatography, etc. , can be isolated by adding a large amount of alcohol such as methanol to a reaction solution containing a polyamide-based resin to precipitate the resin, and performing concentration, filtration, drying, and the like.

<Filler>

The optical film of this invention may also contain at least 1 sort(s) of filler. As a filler, an organic particle, an inorganic particle, etc. are mentioned, for example, Preferably an inorganic particle is mentioned. Examples of the inorganic particles include particles of metal oxides such as silica, zirconia, alumina, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide, antimony oxide and cerium oxide, and metal fluoride particles such as magnesium fluoride and sodium fluoride. Among these, from the viewpoint of increasing the elastic modulus and/or tearing strength of the optical film to easily improve impact resistance, preferably silica particles, zirconia particles, and alumina particles, more preferably silica particles can be mentioned. These fillers can be used individually or in combination of 2 or more types.

The average primary particle diameter of the filler, preferably the silica particles, is usually 1 nm or more, preferably 5 nm or more, more preferably 10 nm or more, still more preferably 15 nm or more, particularly preferably 20 nm or more. , preferably 100 nm or less, more preferably 90 nm or less, still more preferably 80 nm or less, even more preferably 70 nm or less, particularly preferably 60 nm or less, particularly more preferably 50 nm or less, More preferably, it is 40 nm or less. When the average primary particle diameter of a silica particle is in the said range, aggregation of a silica particle is suppressed and it will be easy to improve the optical characteristic of the optical film obtained. The average primary particle diameter of a filler can be measured by BET method. In addition, you may measure an average primary particle diameter by image analysis of a transmission electron microscope or a scanning electron microscope.

When the optical film of this invention contains a filler, Preferably a silica particle, content of a filler is 0.1 mass part or more normally with respect to 100 mass parts of optical films, Preferably it is 1 mass part or more, More preferably, 5 It is mass part or more, More preferably, it is 10 mass parts or more, More preferably, it is 20 mass parts or more, Especially preferably, it is 30 mass parts or more, Preferably it is 60 mass parts or less. It will be easy to improve the elasticity modulus of the optical film obtained as content of a filler is more than the said minimum. Moreover, it will be easy to improve the optical characteristic of an optical film as content of a filler is below the said upper limit.

<Ultraviolet absorbent>

The optical film of this invention may also contain at least 1 sort(s) of ultraviolet absorber. A ultraviolet absorber can be suitably selected from what is normally used as a ultraviolet absorber in the field|area of a resin material. The ultraviolet absorber may contain the compound which absorbs the light of the wavelength of 400 nm or less. Examples of the ultraviolet absorber include at least one compound selected from the group consisting of a benzophenone-based compound, a salicylate-based compound, a benzotriazole-based compound, and a triazine-based compound. A ultraviolet absorber can be used individually or in combination of 2 or more types. When an optical film contains a ultraviolet absorber, since deterioration of resin is suppressed, when the optical film of this invention is applied to a display apparatus etc., visibility can be improved. In this specification, a "system compound" refers to the derivative of the compound to which the said "system compound" is attached. For example, a "benzophenone-based compound" refers to a compound having benzophenone as a parent skeleton and a substituent bonded to benzophenone.

When the optical film of this invention contains a ultraviolet absorber, content of a ultraviolet absorber becomes like this with respect to the mass of polyamide-type resin contained in an optical film, Preferably it is 0.01-10 mass parts, More preferably, it is 1-8 mass part, More preferably, it is 2-7 mass parts. It is easy to improve ultraviolet absorbency as content of a ultraviolet absorber is more than the said minimum. When content of a ultraviolet absorber is below the said upper limit, decomposition|disassembly of the ultraviolet absorber by the heat at the time of base material manufacture can be suppressed, it is easy to improve an optical characteristic, for example, it is easy to reduce a haze.

<Other additives>

The optical film of this invention may contain other additives other than a filler and a ultraviolet absorber further. As another additive, antioxidant, mold release agents, stabilizers, coloring agents, such as a bluing agent, a flame retardant, a pH adjuster, a silica dispersing agent, a lubricant, a thickener, a leveling agent, etc. are mentioned, for example. When containing another additive, the content becomes like this with respect to the mass of an optical film. Preferably it is 0.001-20 mass parts, More preferably, it is 0.01-15 mass parts, More preferably, 0.1-10 mass parts may be sufficient.

(Manufacturing method of optical film)

Although the manufacturing method of the optical film of this invention is not specifically limited, For example, the following process:

(a) a step of preparing a polyamide-based resin composition containing at least the polyamide-based resin and a solvent (hereinafter also referred to as “varnish”) (varnish preparation step);

(b) applying the varnish to the support material to form a coating film (application step), and

(c) The process of drying the applied liquid (coating film) and forming an optical film (optical film formation process)

A manufacturing method comprising

A varnish preparation process WHEREIN: A varnish is prepared by melt|dissolving polyamide-type resin in a solvent, adding additives, such as the said filler and a ultraviolet absorber, as needed, and stirring and mixing. In addition, when using silica particles as a filler, a silica sol in which the dispersion of silica sol containing silica particles is substituted with a solvent in which the resin is soluble, for example, a solvent used for the preparation of the following varnish, may be added to the resin. do.

The solvent used for preparation of a varnish will not be specifically limited if the said resin can be melt|dissolved. Examples of such solvents include amide solvents such as N,N-dimethylacetamide and N,N-dimethylformamide; lactone solvents such as γ-butyrolactone and γ-valerolactone; sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide, and sulfolane; carbonate solvents such as ethylene carbonate and propylene carbonate; and combinations thereof. Among these, an amide-based solvent or a lactone-based solvent is preferable. These solvents can be used individually or in combination of 2 or more types. Further, the varnish may contain water, an alcohol-based solvent, a ketone-based solvent, an acyclic ester-based solvent, an ether-based solvent, and the like. Solid content concentration of a varnish becomes like this. Preferably it is 1-25 mass %, More preferably, it is 5-20 mass %, More preferably, it is 5-15 mass %.

A coating process WHEREIN: A varnish is apply|coated on a support material by a well-known coating method, and a coating film is formed. As a known coating method, for example, a roll coating method such as a wire bar coating method, reverse coating, gravure coating, a die coating method, a comma coating method, a lip coating method, a spin coating method, a screen coating method, a fountain coating method, a Die coating method The ping method, the spray method, the casting method, etc. are mentioned.

A film formation process WHEREIN: An optical film can be formed by drying a coating film and peeling from a support material. You may provide the process of further drying an optical film after peeling. Drying of a coating film can be performed at the temperature of 50-350 degreeC normally. If necessary, the coating film may be dried under an inert atmosphere or under reduced pressure.

Examples of the support material include a SUS plate if it is a metal type, a PET film, a PEN film, a polyamide type resin film, a polyimide type resin film, a cycloolefin type polymer (COP) film, an acrylic type film if it is a resin type. Especially, from a viewpoint of being excellent in smoothness and heat resistance, a PET film, a COP film, etc. are preferable, and also from a viewpoint of adhesiveness with an optical film, and a viewpoint of cost, PET film is more preferable.

(functional layer)

One or more functional layers may be laminated|stacked on at least one surface of the optical film of this invention. As a functional layer, an ultraviolet-ray absorption layer, a hard-coat layer, a primer layer, a gas barrier layer, an adhesion layer, a hue adjustment layer, a refractive index adjustment layer, etc. are mentioned, for example. A functional layer can be used individually or in combination of 2 or more types.

A hard-coat layer may be provided in at least one surface of the optical film of this invention. The thickness of a hard-coat layer is not specifically limited, For example, 2-100 micrometers may be sufficient. When the thickness of the hard coat layer is in the above range, sufficient scratch resistance can be ensured, and bending resistance is less likely to decrease, and the problem of curling due to curing shrinkage tends to be less likely to occur.

The said hard-coat layer can harden|cure the hard-coat composition containing the reactive material which can form a crosslinked structure by active energy ray irradiation or thermal energy application, and it is preferable to form by active energy ray irradiation. Active energy rays are defined as energy rays that can generate active species by decomposing compounds that generate active species, and include visible light, ultraviolet rays, infrared rays, X-rays, α-rays, β-rays, γ-rays, and electron beams. and, preferably, ultraviolet rays. The said hard-coat composition contains the at least 1 sort(s) of polymer of a radically polymerizable compound and a cationically polymerizable compound.

The said radically polymerizable compound is a compound which has a radically polymerizable group. The radical polymerizable group of the radical polymerizable compound may be a functional group capable of generating a radical polymerization reaction, and examples thereof include a group containing a carbon-carbon unsaturated double bond, and specifically, a vinyl group, (meth) An acryloyl group etc. are mentioned. In addition, when the said radically polymerizable compound has two or more radically polymerizable groups, these radically polymerizable groups may mutually be same or different. The number of radically polymerizable groups which the said radically polymerizable compound has in 1 molecule is a point which improves the hardness of a hard-coat layer, Preferably it is 2 or more. As said radically polymerizable compound, it is a point with high reactivity, Preferably the compound which has a (meth)acryloyl group is mentioned, Specifically, it is polyfunctional which has 2-6 pieces of (meth)acryloyl group in 1 molecule. Compounds called acrylate monomers or oligomers with several (meth)acryloyl groups in the molecule called epoxy (meth)acrylate, urethane (meth)acrylate, and polyester (meth)acrylate having a molecular weight of hundreds to thousands and preferably at least one selected from epoxy (meth)acrylate, urethane (meth)acrylate, and polyester (meth)acrylate.

The said cationically polymerizable compound is a compound which has cationically polymerizable groups, such as an epoxy group, an oxetanyl group, and a vinyl ether group. The number of the cationically polymerizable groups which the said cationically polymerizable compound has in 1 molecule is a point which improves the hardness of a hard-coat layer, Preferably it is 2 or more, More preferably, it is 3 or more.

Moreover, as said cationically polymerizable compound, the compound which has at least 1 sort(s) of an epoxy group and oxetanyl group as a cationically polymerizable group is especially preferable. Cyclic ether groups, such as an epoxy group and an oxetanyl group, are preferable at the point that the shrinkage accompanying a polymerization reaction is small. Moreover, the compound which has an epoxy group among a cyclic ether group has the advantage that it is easy to obtain the compound of various structures, does not exert a bad influence on the durability of the obtained hard-coat layer, Compatibility with a radically polymerizable compound is also easy to control. In addition, the oxetanyl group in the cyclic ether group tends to have a higher degree of polymerization compared with the epoxy group, speeds up the network formation rate obtained from the cationically polymerizable compound of the obtained hard coat layer, and is unreacted even in the region where it is mixed with the radically polymerizable compound. There are advantages such as forming an independent network without leaving any monomers in the film.

As the cationically polymerizable compound having an epoxy group, for example, a polyglycidyl ether of a polyhydric alcohol having an alicyclic ring or a cyclohexene ring or a cyclopentene ring-containing compound is epoxidized with a suitable oxidizing agent such as hydrogen peroxide or peracid. an alicyclic epoxy resin obtained by Aliphatic epoxy resins, such as polyglycidyl ether of an aliphatic polyhydric alcohol or its alkylene oxide adduct, polyglycidyl ester of an aliphatic long-chain polybasic acid, and a homopolymer and copolymer of glycidyl (meth)acrylate; Glycidyl ether produced by reaction of bisphenols such as bisphenol A, bisphenol F and hydrogenated bisphenol A, or derivatives such as alkylene oxide adducts and caprolactone adducts thereof with epichlorhydrin and glycidyl ether type epoxy resins derived from bisphenols as novolac epoxy resins and the like.

The hard coat composition may further include a polymerization initiator. As a polymerization initiator, a radical polymerization initiator, a cationic polymerization initiator, a radical, a cationic polymerization initiator, etc. are mentioned, It selects suitably and is used. Such a polymerization initiator decomposes by at least 1 sort(s) of active energy ray irradiation and heating, generate|occur|produces a radical or a cation, and advances radical polymerization and cationic polymerization.

A radical polymerization initiator should just be able to release|release the substance which initiates radical polymerization by at least any of active energy ray irradiation and heating. For example, as a thermal radical polymerization initiator, organic peroxides, such as hydrogen peroxide and perbenzoic acid, Azo compounds, such as azobisbutyronitrile, etc. are mentioned.

As the active energy ray radical polymerization initiator, there are a Type 1 radical polymerization initiator in which radicals are generated by decomposition of molecules, and a Type 2 radical polymerization initiator in which radicals are generated in a hydrogen extraction reaction by coexisting with a tertiary amine. used as or in combination.

A cationic polymerization initiator should just be able to release|release the substance which starts cationic polymerization by at least any of active energy ray irradiation and heating. As a cationic polymerization initiator, an aromatic iodonium salt, an aromatic sulfonium salt, a cyclopentadienyl iron(II) complex, etc. can be used. These can initiate cationic polymerization in any or any of active energy ray irradiation or heating depending on the difference in structure.

Preferably the said polymerization initiator may contain 0.1-10 mass % with respect to 100 mass % of the total of the said hard-coat composition. When the content of the polymerization initiator is within the above range, curing can be sufficiently progressed, and the mechanical properties and adhesion of the finally obtained coating film can be within a good range, and also, poor adhesion due to curing shrinkage, cracking, and curling. The phenomenon tends to be difficult to occur.

The hard coat composition may further include one or more selected from the group consisting of solvents and additives. The solvent can dissolve or disperse the polymerizable compound and the polymerization initiator, and as long as it is a solvent known as a solvent for a hard coat composition in the technical field, it can be used within a range that does not impair the effects of the present invention. The additive may further include inorganic particles, a leveling agent, a stabilizer, a surfactant, an antistatic agent, a lubricant, an antifouling agent, and the like.

The ultraviolet absorbing layer is a layer having a function of absorbing ultraviolet rays, and includes, for example, a main material selected from an ultraviolet curable transparent resin, an electron beam curable transparent resin, and a thermosetting transparent resin, and dispersed in the main material. It consists of a UV absorber.

An adhesion layer is a layer which has an adhesive function, and has a function to adhere|attach an optical film to another member. As a material for forming the pressure-sensitive adhesive layer, a commonly known material can be used. For example, a thermosetting resin composition or a photocurable resin composition can be used. In this case, the resin composition can be polymerized and cured by supplying energy afterwards.

The pressure-sensitive adhesive layer may be a layer that is adhered to the object by pressure, called a pressure sensitive adhesive (PSA). The pressure-sensitive adhesive may be a pressure-sensitive adhesive that is "a substance that has tackiness at room temperature and adheres to an adherend with light pressure" (JIS K 6800), "a specific component is contained in a protective film (microcapsule), A capsule adhesive which is "adhesive (JIS K 6800)" which can maintain stability until the film is destroyed by means (pressure, heat, etc.) may be sufficient.

A color adjustment layer is a layer which has a function of color adjustment, and is a layer which can adjust the laminated body containing an optical film to the target color. The color adjustment layer is, for example, a layer containing a resin and a colorant. Examples of the colorant include inorganic pigments such as titanium oxide, zinc oxide, bengala, titanium oxide calcined pigments, ultramarine blue, cobalt aluminate, and carbon black; organic pigments such as azo compounds, quinacridone compounds, anthraquinone compounds, perylene compounds, isoindolinone compounds, phthalocyanine compounds, quinophthalone compounds, srene compounds, and diketopyrrolopyrrole compounds; extender pigments such as barium sulfate and calcium carbonate; and dyes such as basic dyes, acid dyes, and mordant dyes.

A refractive index adjustment layer is a layer which has a function of refractive index adjustment, has a refractive index different from an optical film, for example, is a layer which can provide a predetermined refractive index to an optical laminated body. The refractive index-adjusting layer may be, for example, a resin layer further containing a resin selected appropriately and a pigment according to the case, or may be a thin metal film. As a pigment which adjusts a refractive index, a silicon oxide, aluminum oxide, antimony oxide, a tin oxide, a titanium oxide, a zirconium oxide, and a tantalum oxide are mentioned, for example. The average primary particle diameter of the pigment may be 0.1 µm or less. By setting the average primary particle diameter of the pigment to 0.1 µm or less, diffuse reflection of the light passing through the refractive index adjusting layer can be prevented, and a decrease in transparency can be prevented. Examples of the metal used for the refractive index adjusting layer include metal oxides such as titanium oxide, tantalum oxide, zirconium oxide, zinc oxide, tin oxide, silicon oxide, indium oxide, titanium oxynitride, titanium nitride, silicon oxynitride, and silicon nitride; and metal nitrides.

In one preferred embodiment of the present invention, the optical film of the present invention is useful as a front plate of a display device, particularly a front plate of a flexible display device (hereinafter sometimes referred to as a window film). A flexible display device has, for example, a flexible functional layer and an optical film which is superimposed on the flexible functional layer and functions as a front plate. That is, the front plate of the flexible display device is disposed on the visual recognition side above the flexible functional layer. This front plate has a function of protecting a flexible functional layer.

As a display device, wearable devices, such as a television, a smart phone, a mobile phone, a car navigation system, a tablet PC, a portable game machine, electronic paper, an indicator, a bulletin board, a watch, and a smart watch, etc. are mentioned. As a flexible display device, all the display devices which have a flexible characteristic are mentioned.

[Flexible Display Device]

The present invention also provides a flexible display device comprising the optical film of the present invention. The optical film of the present invention is preferably used as a front plate in a flexible display device, and the front plate is sometimes called a window film. The said flexible display device consists of the laminated body for flexible display devices, and an organic electroluminescent display panel, with respect to the organic electroluminescent display panel, the flexible display laminated body is arrange|positioned on the visual recognition side, and it is comprised so that it can bend. The laminate for a flexible display device may contain a window film, a polarizing plate, preferably a circularly polarizing plate, and a touch sensor, and the lamination order thereof is arbitrary, but a window film, a polarizing plate, a touch sensor or a window film, and a touch sensor from the viewer side , it is preferably laminated in the order of the polarizing plates. When a polarizing plate exists on the visual recognition side of a touch sensor, since it becomes difficult to visually recognize the pattern of a touch sensor, and the visibility of a display image improves, it is preferable. Each member may be laminated using an adhesive, an adhesive, or the like. In addition, a light blocking pattern formed on at least one surface of any layer of the window, the polarizing plate, and the touch sensor may be provided.

[Polarizer]

The flexible display device of the present invention may further include a polarizing plate, preferably a circularly polarizing plate. The circularly polarizing plate is a functional layer having a function of transmitting only the right circularly polarized light component or the left circularly polarized light component by laminating a λ/4 retardation plate on the linearly polarizing plate. For example, it is used to convert external light into right circularly polarized light, block external light that has been reflected by the organic EL panel to become left circularly polarized light, and transmits only luminescent components of organic EL to suppress the influence of reflected light and make the image easier to see. In order to achieve the circularly polarized light function, the absorption axis of the linear polarizing plate and the slow axis of the λ/4 retarder need to be 45° in theory, but 45±10° in practice. The linear polarizing plate and the λ/4 retardation plate do not necessarily need to be stacked adjacent to each other, and the relationship between the absorption axis and the slow axis may satisfy the above-mentioned range. Although it is desirable to achieve perfect circularly polarized light at all wavelengths, it is not necessary for practical use. Therefore, the circularly polarizing plate in the present invention also includes an elliptically polarizing plate. It is also preferable to further laminate a λ/4 retardation film on the visual recognition side of the linear polarizing plate and to make the emitted light circularly polarized to improve visibility in a state in which polarized sunglasses are worn.

The linear polarizing plate is a functional layer having a function of passing light vibrating in the transmission axis direction, but blocking polarization of a vibration component perpendicular to it. The linear polarizing plate may be configured to include a linear polarizer alone or a linear polarizer and a protective film affixed on at least one surface thereof. The thickness of the said linear polarizing plate may be 200 micrometers or less, Preferably it is 0.5-100 micrometers. When the thickness is within the above range, the flexibility tends to be less likely to decrease.

The linear polarizer may be a film-type polarizer manufactured by dyeing and stretching a polyvinyl alcohol (PVA)-based film. A dichroic dye orientates and exhibits polarization|polarized-light performance by extending|stretching in the state adsorbed to PVA system film orientated by extending|stretching, dichroic dyes, such as iodine, or PVA. In manufacture of the said film polarizer, you may have other processes, such as swelling, bridge|crosslinking by boric acid, washing|cleaning by aqueous solution, and drying. The stretching and dyeing steps may be performed alone or in a laminated state with other films such as polyethylene terephthalate. The thickness of the PVA-based film used is preferably 10 to 100 µm, and the draw ratio is preferably 2 to 10 times.

Moreover, as another example of the said polarizer, the liquid crystal application type polarizer formed by apply|coating a liquid crystal polarizing composition may be sufficient. The liquid crystal polarizing composition may include a liquid crystal compound and a dichroic dye compound. The said liquid crystalline compound may have the property which shows a liquid crystal state, and since high polarization performance can be exhibited when it has high-order orientation states, such as a smectic phase, it is preferable. Moreover, it is also preferable that a liquid crystalline compound has a polymerizable functional group.

The said dichroic dye is a pigment|dye which orientates together with the said liquid crystal compound and shows dichroism, The dichroic dye itself may have liquid crystallinity, and may have a polymerizable functional group. Any compound in the liquid crystal polarizing composition has a polymerizable functional group.

The liquid crystal polarizing composition may further include an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, and the like.

The liquid crystal polarizing layer is prepared by coating a liquid crystal polarizing composition on an alignment layer to form a liquid crystal polarizing layer.

A liquid crystal polarizing layer can be formed thinly compared with a film-type polarizer. Preferably the thickness of the said liquid crystal polarizing layer is 0.5-10 micrometers, More preferably, it may be 1-5 micrometers.

The alignment film can be produced, for example, by applying an alignment film forming composition on a substrate and imparting orientation by rubbing, polarized light irradiation, or the like. The said alignment film formation composition may contain the solvent, a crosslinking agent, an initiator, a dispersing agent, a leveling agent, a silane coupling agent, etc. other than an alignment agent. As said aligning agent, polyvinyl alcohol, polyacrylates, polyamic acids, and polyimides can be used, for example. In the case of applying photo-alignment, it is preferable to use an alignment agent containing a cinnamate group. The weight average molecular weight of the polymer used as the alignment agent may be about 10,000 to 1,000,000. The thickness of the alignment film is preferably 5 to 10,000 nm, more preferably 10 to 500 nm from the viewpoint of the alignment regulating force. The liquid crystal polarizing layer may be laminated by being peeled off from the substrate and transferred, or the substrate may be laminated as it is. It is also preferable that the said base material bears the role as a transparent base material of a protective film, a retardation plate, and a window.

As said protective film, what is necessary is just a transparent polymer film, The material and additive used for the said transparent base material can be used. A cellulosic film, an olefinic film, an acrylic film, and a polyester-type film are preferable. The protective film of the coating type obtained by apply|coating and hardening|curing cation hardening compositions, such as an epoxy resin, and radical hardening compositions, such as an acrylate, may be sufficient. If necessary, a plasticizer, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or dye, an optical brightener, a dispersant, a heat stabilizer, a light stabilizer, an antistatic agent, an antioxidant, a lubricant, a solvent, etc. may be included. The thickness of the said protective film may be 200 micrometers or less, Preferably, it is 1-100 micrometers. When the thickness of the protective film is in the above range, the flexibility of the protective film is less likely to decrease. A protective film can also serve as the transparent base material of a window.

The λ/4 retardation plate is a film imparting a retardation of λ/4 in a direction orthogonal to the traveling direction of the incident light, that is, in the in-plane direction of the film. The λ/4 retardation plate may be a stretched retardation plate manufactured by stretching a polymer film such as a cellulose-based film, an olefin-based film, or a polycarbonate-based film. If necessary, retardation adjuster, plasticizer, ultraviolet absorber, infrared absorber, colorant such as pigment or dye, optical brightener, dispersant, heat stabilizer, light stabilizer, antistatic agent, antioxidant, lubricant, solvent, etc. may be included. The thickness of the said stretched retardation plate may be 200 micrometers or less, Preferably it is 1-100 micrometers. When the thickness is within the above range, the flexibility of the film tends to be difficult to decrease.

Further, as another example of the λ/4 retardation plate, a liquid crystal coating type retardation plate formed by applying a liquid crystal composition may be used. The liquid crystal composition includes a liquid crystal compound having a property of exhibiting a liquid crystal state such as nematic, cholesteric, and smectic. Any compound including the liquid crystalline compound in the liquid crystal composition has a polymerizable functional group. The liquid crystal coating type retardation plate may further include an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, and the like. The liquid crystal coating type retardation plate can be manufactured by coating and curing a liquid crystal composition on an alignment film to form a liquid crystal retardation layer, similarly to the substrate in the liquid crystal polarizing layer. The liquid-crystal-coated retardation plate can be formed to be thinner than the stretch-type retardation plate. The thickness of the said liquid crystal polarizing layer is 0.5-10 micrometers normally, Preferably 1-5 micrometers may be sufficient. The liquid-crystal-coated retardation plate may be laminated by peeling off the substrate and transferring it, or the substrate may be laminated as it is. It is also preferable that the said base material plays a role as a transparent base material of a protective film, retardation plate, and a window.

In general, there are many materials that exhibit greater birefringence for shorter wavelengths and smaller birefringence for longer wavelengths. In this case, since a phase difference of λ/4 cannot be achieved in the entire visible light region, it is designed so that the in-plane retardation of λ/4 becomes λ/4 in the vicinity of 560 nm, which is high in visibility, of 100 to 180 nm, preferably 130 to 150 nm. often becomes It is preferable to use a reverse dispersion λ/4 retarder using a material having a birefringence wavelength dispersion characteristic opposite to that of usual because visibility can be improved. As such a material, it is also preferable to use those described in Japanese Patent Application Laid-Open No. 2007-232873, etc. in the case of a stretched retardation plate, and in Japanese Patent Laid-Open No. 2010-30979 in the case of a liquid crystal coating type retardation plate.

In addition, as another method, a technique for obtaining a broadband λ/4 retardation plate by combining it with a λ/2 retarder is also known (Japanese Patent Laid-Open No. 10-90521). The λ/2 retardation plate is also manufactured by the same material method as the λ/4 retardation plate. Although the combination of the stretched retardation plate and the liquid crystal coating type retardation plate is arbitrary, it is preferable to use either the liquid crystal coating type retardation plate because the thickness can be made thin.

A method of laminating a positive C plate on the circular polarizing plate in order to increase visibility in an oblique direction is also known (Japanese Patent Laid-Open No. 2014-224837). The positive C plate may also be a liquid-crystal coating type retarder or a stretched retardation plate. The retardation in the thickness direction is -200 to -20 nm, preferably -140 to -40 nm.

[Touch sensor]

The flexible display device of the present invention may further include a touch sensor. A touch sensor is used as an input means. As a touch sensor, various styles, such as a resistive film method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, and a capacitive method, are proposed, and any method may be used. Among them, the electrostatic capacitive method is preferable. The capacitive touch sensor is divided into an active area and an inactive area located outside the active area. The active area is an area corresponding to a display unit on which a screen is displayed on the display panel, and is an area where a user's touch is sensed, and the inactive area is an area corresponding to a non-display unit on which a screen is not displayed on the display device. The touch sensor includes: a substrate having flexible characteristics; a sensing pattern formed in the active region of the substrate; Each sensing line is formed in the non-active area of the substrate and connected to an external driving circuit through the sensing pattern and the pad part. As a board|substrate which has a flexible characteristic, the material similar to the transparent board|substrate of the said window can be used. As for the board|substrate of a touch sensor, it is preferable from the point of crack suppression of a touch sensor that the toughness is 2,000 MPa% or more. More preferably, the toughness may be 2,000 to 30,000 MPa%. Here, the toughness is defined as the area under the curve from the stress-strain curve obtained through the tensile test of the polymer material to the fracture point.

The sensing pattern may include a first pattern formed in a first direction and a second pattern formed in a second direction. The first pattern and the second pattern are arranged in different directions. The first pattern and the second pattern are formed on the same layer, and in order to sense a touched point, each pattern must be electrically connected. In the first pattern, each unit pattern is connected to each other through a seam, but in the second pattern, each unit pattern is separated from each other in an island form. I need this. As the sensing pattern, a known transparent electrode material may be applied. For example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), indium gallium zinc oxide (IGZO), cadmium tin oxide (CTO), PEDOT (poly (3,4-ethylenedioxythiophene)), carbon nanotubes (CNT), graphene, and metal wires, and these may be used alone or in combination of two or more. Preferably, ITO can be used. The metal used for a metal wire is not specifically limited, For example, silver, gold, aluminum, copper, iron, nickel, titanium, selenium, chromium, etc. are mentioned. These can be used individually or in mixture of 2 or more types.

The bridge electrode may be formed on the insulating layer by interposing an insulating layer on the sensing pattern, the bridge electrode may be formed on a substrate, and the insulating layer and the sensing pattern may be formed thereon. The bridge electrode may be formed of the same material as the sensing pattern, or may be formed of a metal such as molybdenum, silver, aluminum, copper, palladium, gold, platinum, zinc, tin, titanium, or an alloy of two or more thereof. Since the first pattern and the second pattern must be electrically insulated, an insulating layer is formed between the sensing pattern and the bridge electrode. The insulating layer may be formed only between the seam of the first pattern and the bridge electrode, or may be formed in the structure of a layer covering the sensing pattern. In the latter case, the bridge electrode may connect the second pattern through a contact hole formed in the insulating layer. The touch sensor is configured to properly compensate for a difference in transmittance between a pattern region in which a pattern is formed and a non-pattern region in which a pattern is not formed, specifically, a difference in light transmittance caused by a difference in refractive index in these regions. An optical control layer may be further included between the substrate and the electrode as a means for this, and the optical control layer may include an inorganic insulating material or an organic insulating material. The optical control layer may be formed by coating a photocurable composition including a photocurable organic binder and a solvent on a substrate. The photocurable composition may further include inorganic particles. The refractive index of the optical control layer may be increased by the inorganic particles.

The photocurable organic binder may include, for example, a copolymer of each monomer such as an acrylate-based monomer, a styrene-based monomer, or a carboxylic acid-based monomer. The photocurable organic binder may be, for example, a copolymer including each repeating unit different from each other, such as an epoxy group-containing repeating unit, an acrylate repeating unit, and a carboxylic acid repeating unit.

The inorganic particles may include, for example, zirconia particles, titania particles, alumina particles, and the like. The said photocurable composition may further contain each additive, such as a photoinitiator, a polymerizable monomer, and a hardening adjuvant.

[Adhesive layer]

Each layer, such as a window film, a polarizing plate, and a touch sensor, which forms the laminated body for the said flexible display device, and film members, such as a linear polarizing plate and λ/4 retardation plate constituting each layer, can be adhered with an adhesive. Examples of the adhesive include water-based adhesives, organic solvent-based adhesives, solvent-free adhesives, solid adhesives, solvent volatilization adhesives, moisture curing adhesives, heat curing adhesives, anaerobic curing adhesives, active energy ray curing adhesives, curing agent mixed adhesives, hot melt adhesives, What is commonly used, such as a pressure-sensitive adhesive, a pressure-sensitive adhesive, and a rewet adhesive, can be used. Among them, a water-based solvent volatilization type adhesive, an active energy ray-curable adhesive, and an adhesive are frequently used. The thickness of the adhesive layer can be appropriately adjusted according to the required adhesive force and the like, and is, for example, 0.01 to 500 μm, preferably 0.1 to 300 μm. Although two or more adhesive layers may exist in the said laminated body for flexible display devices, each thickness and the kind of adhesive agent used may be same or different.

As the water-based solvent volatilization type adhesive, a water-dispersed polymer such as a polyvinyl alcohol-based polymer and a water-soluble polymer such as starch, an ethylene-vinyl acetate emulsion, or a styrene-butadiene emulsion can be used as the main polymer. In addition to water and the main polymer, a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, an antioxidant, a dye, a pigment, an inorganic filler, an organic solvent, and the like may be blended. When adhere|attaching with the said water-based solvent volatilization type adhesive agent, adhesiveness can be provided by pouring the said water-based solvent volatilization type adhesive agent between to-be-adhesive layers and bonding to-be-adhered layers, by drying. The thickness of the adhesive layer in the case of using the said water-based solvent volatilization type adhesive agent is 0.01-10 micrometers, Preferably it may be 0.1-1 micrometer. When using the said water-system solvent volatilization type adhesive agent for formation of multiple layers, the thickness of each layer and the kind of the said adhesive agent may be same or different.

The said active energy ray hardening-type adhesive agent can be formed by hardening of the active energy ray hardening composition containing the reactive material which irradiates an active energy ray and forms an adhesive bond layer. The said active energy ray hardening composition can contain the at least 1 sort(s) of polymer of the radically polymerizable compound similar to a hard-coat composition, and a cationically polymerizable compound. The said radically polymerizable compound is the same as that of a hard-coat composition, The thing of the same kind as a hard-coat composition can be used. As a radically polymerizable compound used for a contact bonding layer, the compound which has an acryloyl group is preferable. It is also preferable to include a monofunctional compound in order to lower the viscosity as an adhesive composition.

The said cationically polymerizable compound is the same as that of a hard-coat composition, The thing of the same kind as a hard-coat composition can be used. As a cationically polymerizable compound used for an active energy ray hardening composition, an epoxy compound is especially preferable. It is also preferable to include a monofunctional compound as a reactive diluent in order to lower the viscosity of the adhesive composition.

The active energy ray composition may further include a polymerization initiator. As a polymerization initiator, they are a radical polymerization initiator, a cationic polymerization initiator, a radical, a cationic polymerization initiator, etc., They can select and use suitably. Such a polymerization initiator is decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to advance radical polymerization and cationic polymerization. An initiator capable of initiating at least either radical polymerization or cationic polymerization by irradiation with an active energy ray in the substrate of the hard coat composition can be used.

The active energy ray curing composition may further include an ion scavenger, an antioxidant, a chain transfer agent, a adhesion imparting agent, a thermoplastic resin, a filler, a flow viscosity modifier, a plasticizer, an antifoaming agent solvent, an additive, and a solvent. In the case of bonding with the active energy ray-curable adhesive, the active energy ray curing composition is applied to any or both of the adherend layers and then bonded, passed through any adherend layer or both adherend layers, and is cured by irradiating active energy rays It can be adhered by The thickness of the adhesive layer in the case of using the said active energy ray hardening-type adhesive agent is 0.01-20 micrometers, Preferably it may be 0.1-10 micrometers. When using the said active energy ray hardening-type adhesive agent for formation of multiple layers, the thickness of each layer and the kind of adhesive agent used may be same or different.

The pressure-sensitive adhesive is classified into an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, and the like depending on the main polymer, and any of these may be used. You may mix|blend a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, antioxidant, a tackifier, a plasticizer, dye, a pigment, an inorganic filler, etc. with an adhesive in addition to a main polymer. Each component constituting the pressure-sensitive adhesive is dissolved and dispersed in a solvent to obtain a pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition is applied on a substrate and then dried to form an adhesive layer or an adhesive layer. The pressure-sensitive adhesive layer may be directly formed, or the adhesive layer may be transferred separately from the substrate. In order to cover the adhesive surface before adhesion, it is also preferable to use a release film. The thickness of the contact bonding layer in the case of using the said adhesive is 1-500 micrometers, Preferably it may be 2-300 micrometers. When using the said adhesive for formation of multiple layers, the thickness of each layer and the kind of adhesive used may be same or different.

[Shading Pattern]

The light blocking pattern may be applied as at least a part of a bezel or a housing of the flexible display device. By hiding the wiring arranged in the peripheral portion of the flexible display device by the light-shielding pattern and making it difficult to be visually recognized, the visibility of the image is improved. The light-shielding pattern may be in the form of a single layer or a multilayer. The color of the light blocking pattern is not particularly limited, and may have various colors such as black, white, and metallic colors. The light-shielding pattern may be formed of a pigment for realizing a color, and a polymer such as an acrylic resin, an ester-based resin, an epoxy-based resin, polyurethane, or silicone. These can also be used individually or in mixture of 2 or more types. The light-shielding pattern can be formed by various methods such as printing, lithography, and inkjet. The thickness of the light-shielding pattern is usually 1 to 100 µm, preferably 2 to 50 µm. Moreover, it is also preferable to provide a shape, such as an inclination, in the thickness direction of a light-shielding pattern.

(Example)

Hereinafter, the present invention will be described in more detail by way of Examples. "%" and "part" in an example mean mass % and a mass part, unless otherwise indicated. First, an evaluation method will be described.

<Measurement of modulus of elasticity>

The elastic modulus of the polyamide film obtained in the Example and the comparative example was measured using "Autograph AG-IS" by Shimadzu Corporation. A film having a width of 10 mm in length and width was produced, the S-S curve was measured under the conditions of a distance between chucks of 50 mm and a tensile rate of 10 mm/min, and the elastic modulus was calculated from the inclination.

<Measurement of light transmittance>

Based on JISK7105:1981, the optical film obtained by the Example and the comparative example was measured for the total light transmittance (Tt) of a sample with the fully automatic direct-reading haze computer HGM-2DP manufactured by Suga Test Instruments Co., Ltd.

<Measurement of Humidity Expansion Coefficient (CME)>

It measured using the "TMA/SS6100 type|mold" manufactured by Hitachi High-Tech Sciences. A film having a width of 2 mm and a length of 20 mm is placed on the chuck in a nitrogen atmosphere (distance between chucks of 10 mm), and held at a load of 20 mN at 60° C. and 0% RH until saturation, and thereafter at 60° C., 90% It controlled by RH and the humidity expansion rate of the film when hold|maintained for 1 hour was measured. In the humidity expansion rate, the length of the film is L (mm), the amount of change in the length of the film before and after holding at 90%RH for 1 hour is ΔL (mm), and the amount of change in humidity is ΔM (%) , and is calculated by the following equation.

Humidity Expansion Rate=(1/L)(ΔL/ΔM)

<YI value of film>

The YI value (Yellow Index) of the sample was measured in accordance with JIS K7373:2006 using an ultraviolet visible near-infrared spectrophotometer V-670 manufactured by Nippon Spectroscopy Co., Ltd. After background measurement was performed in the absence of a sample, the sample was set in a sample holder, transmittance was measured for light of 300 to 800 nm, and tristimulus values (X, Y, Z) were obtained. YI value was computed based on the following formula.

YI=100×(1.2769X-1.0592Z)/Y

<Heize>

The haze of the optical film was measured with a fully automatic direct-reading haze computer HGM-2DP manufactured by Suga Test Instruments Co., Ltd. in accordance with JIS K 7105:1981.

<Measurement of pencil hardness>

As surface hardness of the polyamideimide film obtained in the Example and the comparative example, based on JISK5600-5-4:1999, the pencil hardness of the film surface was employ|adopted. The load was 100 g and a scanning speed of 60 mm/min, the presence or absence of a wound was evaluated in the environment of 4,000 lux, and pencil hardness was measured as surface hardness.

<Measurement of Weight Average Molecular Weight>

Gel Permeation Chromatography (GPC) Measurements

(1) Pretreatment method

DMF eluent (10 mmol/L lithium bromide solution) was added to the sample to a concentration of 2 mg/mL, heated at 80° C. for 30 minutes while stirring, cooled and filtered through a 0.45 μm membrane filter as a measurement solution did it with

(2) Measurement conditions

Column: Tosoh Co., Ltd. TSKgel α-2500 ((7)7.8 mm diameter × 300 mm) × 1 piece, α-M ((13)7.8 mm diameter × 300 mm) × 2 pieces

Eluent: DMF (10 mmol/L lithium bromide added)

Flow rate: 1.0mL/min

Detector: RI Detector

Column temperature: 40℃

Injection volume: 100μL

Molecular weight standard: standard polystyrene

<Measurement of thickness of optical film>

The thickness of the polyamide-type resin film obtained by the Example and the comparative example was measured using the micrometer ("ID-C112XBS" manufactured by Mitsutoyo Co., Ltd.).

<Example 1>

[Preparation of polyamide-based resin (1)]

In a nitrogen atmosphere, in a separable flask equipped with a stirring blade, 2,2'-bis(trifluoromethyl)benzidine (TFMB) and N,N-dimethylacetamide (DMAc) were added to a solid content of 4.90% by mass of TFMB. TFMB was dissolved in DMAc with stirring at room temperature. Next, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA) was added to the flask so that it became 30.30 mol% with respect to TFMB, and it stirred at room temperature for 3 hours. Then, after cooling to 10 ° C., 4,4'oxybis(benzoyl chloride) (OBBC) was added to 5.05 mol% based on TFMB, and 2,5-bis(trifluoromethyl)terephthalic acid chloride (6FTPC) was added to TFMB. It was added so that it might become 27.28 mol% with respect to it, and after stirring for 10 minutes, 5.05 mol% of OBBC and 6FTPC were further added so that it might become 27.28 mol% with respect to TFMB, and it stirred for 30 minutes. Thereafter, DMAc in the same amount as the DMAc added initially was added and stirred for 10 minutes, then 6FTPC was added so as to be 6.06 mol% based on TFMB, and the mixture was stirred for 2 hours. Then, 70.71 mol% of diisopropylethylamine and 4-picoline with respect to TFMB, and 212.12 mol% of acetic anhydride with respect to TFMB were added to the flask, stirred for 30 minutes, and then the internal temperature was raised to 70 ° C. , and further stirred for 3 hours to obtain a reaction solution.

The obtained reaction liquid was cooled to room temperature, and it injected|threw-in in the form of a thread in a large amount of methanol, the precipitated deposit was taken out, immersed in methanol for 6 hours, and it wash|cleaned with methanol. Next, the precipitate was dried under reduced pressure at 60°C to obtain a polyamide-based resin (1).

[Production of polyamide-based resin film (1)]

DMAc was added to the obtained polyamide-based resin (1) so that the concentration was 10% by mass to prepare a polyamide-based resin varnish (1). The obtained polyamide-based resin varnish (1) was coated on the smooth surface of a polyester substrate (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film was 50 µm, and 30°C at 50°C. minute, followed by drying at 140°C for 15 minutes to obtain a self-supporting film. The free-standing film was fixed to a metal mold, and further dried at 200°C for 60 minutes to obtain a polyamide-based resin film (1) having a thickness of 45 µm.

<Example 2>

[Preparation of polyamide-based resin (2)]

In a nitrogen atmosphere, TFMB and DMAc were added to a separable flask equipped with a stirring blade so that the solid content of TFMB was 2.36 mass %, and TFMB was dissolved in DMAc while stirring at room temperature. Next, 6FDA was added to the flask so that it might become 30.30 mol% with respect to TFMB, and it stirred at room temperature for 3 hours. Then, after cooling to 10° C., OBBC was dissolved in 5.5 mol% with respect to TFMB, 2,2'-bis(trifluoromethyl)-4,4'-biphenyldicarboxylic acid chloride (6FBPDOC) was added with respect to TFMB. It added so that it might become 27.28 mol%, and after stirring for 10 minutes, 5.05 mol% of OBBC and 6FBPDOC were further added so that it might become 27.28 mol% with respect to TFMB, and it stirred for 30 minutes. Then, DMAc in the same amount as the DMAc added initially was added, and after stirring for 10 minutes, 6FBPDOC was added so that it might become 6.06 mol% with respect to TFMB, and it stirred for 2 hours. Then, 70.71 mol% of diisopropylethylamine and 4-picoline with respect to TFMB and 212.12 mol% of acetic anhydride with respect to TFMB were added to the flask, and after stirring for 30 minutes, the internal temperature was raised to 70 ° C. , and further stirred for 3 hours to obtain a reaction solution.

The obtained reaction liquid was cooled to room temperature, and it injected|threw-in in the form of a thread in a large amount of methanol, the precipitated deposit was taken out, immersed in methanol for 6 hours, and it wash|cleaned with methanol. Next, the precipitate was dried under reduced pressure at 60°C to obtain a polyamide-based resin (2).

[Production of polyamide-based resin film (2)]

DMAc was added to the obtained polyamide-based resin (2) so that the concentration was 10% by mass to prepare a polyamide-based resin varnish (2). The obtained polyamide-based resin varnish (2) was coated on the smooth surface of a polyester substrate (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film was 55 µm, and 30°C at 50°C. minute, followed by drying at 140°C for 15 minutes to obtain a self-supporting film. The free-standing film was fixed to a metal mold, and further dried at 200°C for 60 minutes to obtain a polyamide-based resin film (2) having a thickness of 50 µm.

<Comparative Example 1>

[Preparation of polyamide-based resin (3)]

In a nitrogen atmosphere, TFMB and DMAc were added to a separable flask equipped with a stirring blade so that the solid content of TFMB was 5.54 mass %, and TFMB was dissolved in DMAc while stirring at room temperature. Next, 6FDA was added to the flask so that it might become 30.20 mol% with respect to TFMB, and it stirred at room temperature for 3 hours. Then, after cooling to 10 degreeC, OBBC was added so that it might become 10.07 mol% with respect to TFMB, and terephthalic acid chloride (TPC) might become 54.35 mol% with respect to TFMB, and it stirred for 30 minutes. Then, DMAc in the same amount as the DMAc added initially was added, and after stirring for 10 minutes, TPC was added so that it might become 6.04 mol% with respect to TFMB, and it stirred for 2 hours. Then, 70.46 mol% of diisopropylethylamine and 4-picoline with respect to TFMB, and 211.37 mol% of acetic anhydride with respect to TFMB were added to the flask, stirred for 30 minutes, and then the internal temperature was raised to 70 ° C. , and further stirred for 3 hours to obtain a reaction solution.

The obtained reaction liquid was cooled to room temperature, and it injected|threw-in in the form of a thread in a large amount of methanol, the precipitated deposit was taken out, immersed in methanol for 6 hours, and it wash|cleaned with methanol. Next, the precipitate was dried under reduced pressure at 60°C to obtain a polyamide-based resin (3).

[Production of polyamide-based resin film (3)]

DMAc was added to the obtained polyamide-based resin (3) so that the concentration was 10% by mass to prepare a polyamide-based resin varnish (3). The obtained polyamide-based resin varnish (3) is coated on the smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film becomes 55 µm, and 30°C at 50°C. minute, followed by drying at 140°C for 15 minutes to obtain a self-supporting film. The free-standing film was fixed to a metal mold, and further dried at 200°C for 60 minutes to obtain a polyamide-based resin film (3) having a thickness of 50 µm.

The weight average molecular weight (Mw) of the obtained polyamide-based resins (1) to (3), and the elastic modulus, CME, light transmittance, YI value and haze of the polyamide-based resin films (1) to (3) were measured by the method described above. was measured according to The obtained results are shown in Table 1. In addition, the pencil hardness of the optical film 1 was 3B, and the pencil hardness of the optical film 2 was 2H.

Claims (15)

Equation (1):
[Formula 1]

[In formula (1), Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,
X ¹ represents a divalent organic group]
A structural unit represented by, and Equation (3):
[Formula 2]

Equation (3) of the, Z ¹ is represented by Ar ^1, or Ar ¹ represents a divalent organic group non-,
Ar ¹ is as defined in the above formula (1),
X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;
An optical film comprising at least a structural unit represented by a polyamide-based resin having a weight average molecular weight of 200,000 to 1,000,000. The method of claim 1,
The optical film in which the C1-C12 fluoroalkyl group ^{in Ar<1>} in Formula (1) is a C1-C12 perfluoroalkyl group. 3. The method according to claim 1 or 2,
The structural unit represented by Formula (1) is Ar ¹ , and Formula (4):
[Formula 3]

[In formula (4), R ¹ represents a fluoroalkyl group having 1 to 12 carbon atoms,
n and k independently represent an integer of 1 to 4, provided that when n and/or k represents an integer of 2 to 4, a plurality of R ¹ may be the same or different from each other,
* indicates a bonding hand]
An optical film comprising an aromatic group represented by . 4. The method of claim 3,
An optical film, wherein two bonding hands in formula (4) are located in a para position to each other. 5. The method according to claim 3 or 4,
The optical film whose k in Formula (4) is 1 or 2. 6. The method according to any one of claims 3 to 5,
^R<1> in Formula (4) represents a C1-C12 perfluoroalkyl group, and n is 1 or 2, The optical film. 7. The method according to any one of claims 1 to 6,
The structural unit represented by Formula (1) and the structural unit represented by Formula (3) are respectively X ¹ and X ² , Formula (5):
[Formula 4]

[In formula (5), Ar ² represents a divalent aromatic group which may have a substituent,
V is a single bond, -O-, a diphenylmethylene group, a fluorenyl group, a linear, branched or alicyclic divalent hydrocarbon group having 1 to 12 carbon atoms, -SO ₂ -, -S-, -CO- , -PO-, -PO ₂ -, -N(R ^a )- or -Si(R ^b ) ₂ -; , R ^a and R ^b each independently represent a hydrogen atom or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom,
m represents an integer of 0 to 3,
* indicates a bonding hand]
An optical film comprising a divalent organic group represented by 8. The method of claim 7,
The optical film whose m in Formula (5) is 1. 9. The method according to claim 7 or 8,
Equation (5) is Equation (5a):
[Formula 5]

[In formula (5), R ² represents a fluoroalkyl group having 1 to 12 carbon atoms,
p and q each independently represent an integer of 1 to 4, provided that when p and/or q represents an integer of 2 to 4, ^{two or} more R 2 may be the same as or different from each other,
* indicates a bonding hand]
Represented by , the optical film. 10. The method of claim 9,
Equation (5a) is Equation (5c):
[Formula 6]

[* in formula (5c) represents a bond]
Represented by , the optical film. 11. The method according to any one of claims 1 to 10,
An optical film having a thickness of 10-200 μm. The flexible display device provided with the optical film in any one of Claims 1-11. 13. The method of claim 12,
A flexible display device further comprising a touch sensor. 14. The method according to claim 12 or 13,
A flexible display device further comprising a polarizing plate. Equation (1):
[Formula 7]

[In formula (1), Ar ¹ represents a divalent aromatic group having a fluoroalkyl group having 1 to 12 carbon atoms,
X ¹ represents a divalent organic group]
^{, and as Ar 1} in Formula (1), Formula (4):
[Formula 8]

[In formula (4), R ¹ represents a fluoroalkyl group having 1 to 12 carbon atoms,
n and k independently represent an integer of 1 to 4, provided that when n and/or k represents an integer of 2 to 4, a plurality of R ¹ may be the same or different from each other,
* indicates a bond]
A structural unit containing an aromatic group represented by, and Formula (3):
[Formula 9]

Equation (3) of the, Z ¹ is represented by Ar ^1, or Ar ¹ represents a divalent organic group non-,
Ar ¹ is as defined in the above formula (1),
X ^2, if represents a divalent organic group, Z ¹ represents the two Ar ^1, X ² of X ¹ and the formula (3) in the formula (1) are different from each other;
A polyamide-based resin having a weight average molecular weight of 200,000 to 1,000,000 having at least a structural unit represented by