JP4686351B2 - Cellulose acylate film, method for producing cellulose acylate film, and polarizing plate and liquid crystal display device using the same - Google Patents

Description

  The present invention relates to a cellulose acylate film, a method for producing a cellulose acylate film, and a polarizing plate and a liquid crystal display device using the same.

  The liquid crystal display device is increasingly used year by year as an image display device with small power consumption and a small space. Conventionally, the large viewing angle dependence of images has been a major drawback of liquid crystal display devices, but in recent years, high viewing angle liquid crystal modes such as VA mode and IPS mode have been put into practical use. The demand for liquid crystal display devices is rapidly expanding even in markets where viewing angles are required.

  Along with this, it is required to develop a wider range of retardation for optical compensation films used in liquid crystal display devices. There are various methods for producing a retardation in a cellulose acylate film and combining the two functions of a polarizing plate protective film and a retardation film, since the manufacturing process of a polarizing plate with an optical compensation function can be greatly simplified. Has been studied.

As a method for imparting retardation to a cellulose acylate film, a method using cellulose acylate having a low acylation degree, a method of adding a compound having a specific shape, and the like are known. In particular, since the latter can adjust the retardation only by the amount of the additive, there is an advantage that films having different retardations can be easily prepared. Document 2 discloses a method of adding a rod-like compound.
JP 2003-344655 A JP 2002-363343 A

  However, these methods have a certain effect, but when higher retardation is required, a large amount of addition is required, and there is a problem that it is difficult to achieve both retardation development and bleed out. Furthermore, there are problems such as in-plane retardation becoming non-uniform.

An object of the present invention is to provide a cellulose acylate film having a uniform and high retardation without causing a planar failure such as bleed out.
Another object of the present invention is to provide a cellulose acylate film having a high retardation and a uniform in-plane retardation without causing a planar failure such as bleed out.
Another object of the present invention is to provide a liquid crystal display device having a wide viewing angle and a high display quality, using a polarizing plate using the cellulose acylate film.

  The researchers of the present invention include in the cellulose acylate film 0.1 to 30% by mass of a retardation increasing agent having polarizability anisotropy and intermolecular end distances within a specific range. Thus, it has been found that the retardation is greatly developed without causing a planar failure such as bleed out. In addition, when the cellulose acylate film containing the above retardation increasing agent is stretched under specific conditions, the degree of orientation of the retardation increasing agent is remarkably improved, so that the retardation can be expressed uniformly and greatly. I found. The present invention has been completed based on these findings.

（式中、Ｒ ^１ 、Ｒ ^２ 、Ｒ ^３ 、Ｒ ^４ 、Ｒ ^５ 、Ｒ ^６ 、Ｒ ^７ 及びＲ ^８ は、それぞれ独立に、水素原子又は置換基を表す。）
一般式（３）：

（式中、Ｒ ^１１ 、Ｒ ^１２ 、Ｒ ^１３ 、Ｒ ^１４ 、Ｒ ^１５ 、Ｒ ^１６ 、Ｒ ^１７ 及びＲ ^１８ は、それぞれ独立に、水素原子又は置換基を表す。）
〔４〕
棒状分極率異方性が３００×１０ ^−２５ ｃｍ ^３ 以上２０００×１０ ^−２５ ｃｍ ^３ 以下であり、分子の末端間距離が２ｎｍ以上１０ｎｍ以下のレターデーション上昇剤が、下記一般式（４）で表される化合物である〔１〕又は〔２〕に記載のセルロースアシレートフィルム。
一般式（４）

（式中、Ｒ ^２−１ 、Ｒ ^４−１ 、Ｒ ^５−１ はそれぞれ水素原子または置換基を表し、Ｒ ^１１−１ 、Ｒ ^１３−１ はそれぞれ水素原子またはアルキル基を表し、Ｌ ^１−１ 、Ｌ ^２−１ はそれぞれ単結合または２価の連結基を表す。Ａｒ ^１−１ はアリーレン基または芳香族へテロ環を表し、Ａｒ ^２−１ はアリール基または芳香族へテロ環を表し、ｎ−１は３以上の整数を表し、ｎ−１種存在するＬ ^２−１ 、Ａｒ ^１−１ はそれぞれ同一であっても異なっていてもよい。ただしＲ ^１１−１ 、Ｒ ^１３−１ は互いに異なっており、Ｒ ^１３−１ で表されるアルキル基はヘテロ原子を含まない。）
〔５〕
棒状分極率異方性が３００××１０ ^−２５ ｃｍ ^３ 以上２０００×１０ ^−２５ ｃｍ ^３ 以下であり、分子の末端間距離が２ｎｍ以上１０ｎｍ以下のレターデーション上昇剤が、下記一般式（５）で表される化合物である〔１〕又は〔２〕に記載のセルロースアシレートフィルム。
一般式（５）

（式中、Ｌ ^１ およびＬ ^２ は、それぞれ、単結合または二価の連結基を表す。Ｒ ^１ およびＲ ^２ は、それぞれ、水素原子または置換基である。Ｒ ^３ およびＲ ^４ は、それぞれ、置換基を表す。ｎは０〜４の整数を表し、ｎが２以上の場合は、複数存在するＲ ^３ はそれぞれ同じでも異なっていてもよく、互いに結合して環を形成してもよい。ｍは０〜４の整数を表し、ｍが２以上の場合は、複数存在するＲ ^４ はそれぞれ同じでも異なっていてもよく、可能であれば互いに結合して環を形成してもよい。Ｘ ^１ は１〜５の整数を表す。Ｘ ^１ が２以上の場合は、複数存在する（Ｒ ^４ ） _ｍ はそれぞれ同じでも異なっていてもよい。Ｒ ^４１ は水素原子または置換基を表す。）
〔６〕
数式（２）で表される平面分極率異方性が３００×１０ ^−２５ ｃｍ ^３ 以上１５００×１０ ^−２５ ｃｍ ^３ 以下で、末端間距離が２ｎｍ以上１０ｎｍ以下のレターデーション上昇剤が、下記一般式（６）で表される化合物である〔１〕又は〔２〕に記載のセルロースアシレートフィルム。
一般式（６）：

（式中、Ｒ ^２１ 、Ｒ ^２２ 及びＲ ^２３ は、それぞれ独立に、アルキル基、アルケニル基、芳香族環基又は複素環基を表す。）
〔７〕
〔１〕〜〔６〕のいずれかに記載のセルロースアシレートフィルムを製造する方法であって、セルロースアシレートフィルムを、１分間に１００％以下の延伸速度で３％以上２００％以下の延伸倍率で延伸した後、最大延伸倍率の５０％以上９９％以下の延伸倍率で、１秒以上１２０秒以下保持することを特徴とするセルロースアシレートフィルムの製造方法。
〔８〕
〔７〕の方法により製造された〔１〕〜〔６〕のいずれかに記載のセルロースアシレートフィルム。
〔９〕
偏光子の両面に保護フィルムが貼り合わされてなる偏光板において、該保護フィルムの少なくとも１枚が、〔１〕〜〔６〕及び〔８〕のいずれかに記載に記載のセルロースアシレートフィルムであることを特徴とする偏光板。
〔１０〕
保護フィルムの少なくとも片方の面上に、光学異方性層を有する〔９〕に記載の偏光板。
〔１１〕
保護フィルムの少なくとも片方の面上に、位相差フィルムが貼り合わされてなる〔９〕に記載の偏光板。
〔１２〕
液晶セル及びその両側に配置された２枚の偏光板を有し、その少なくとも１方の偏光板が〔９〕〜〔１１〕のいずれかに記載の偏光板であることを特徴とする液晶表示装置。
本発明は、上記〔１〕〜〔１２〕に係る発明であるが、以下、それ以外の事項についても記載している。 That is, one aspect of the present invention relates to the following cellulose acylate film.
[1]
At least one type of retardation increase in which the rod-like polarizability anisotropy represented by the following formula (1) is 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and the end-to-end distance is 2 nm or more and 10 nm or less. And at least one kind of agent having a plane polarizability anisotropy represented by the following formula (2) of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less. A cellulose acylate film comprising at least one retardation increasing agent in an amount of 0.1% by mass to 30% by mass with respect to cellulose acylate.
Formula (1): Δα = α _x − (α _y + α _z ) / 2
Formula (2): Δα = (α _x + α _y ) / 2−α _z
( Where α _x is the largest component of eigenvalues obtained after diagonalizing the polarizability tensor ; α _y is the second largest eigenvalue obtained after diagonalizing the polarizability tensor. Α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor.)
[2]
Re and Rth at a wavelength of 590 nm are
20 ≦ Re ≦ 200
70 ≦ Rth ≦ 400
1 ≦ Rth / Re ≦ 10
The cellulose acylate film according to [1], wherein (Re represents in-plane retardation, and Rth represents retardation in the thickness direction.)
[3]
A retardation increasing agent having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (1). The cellulose acylate film according to [1] or [2], which is a compound represented.
General formula (1):
Ar ¹ -L ¹ -XL ² -Ar ²
{In the formula, Ar ¹ and Ar ² each independently represent an aryl group or an aromatic heterocycle. L ¹ and L ² each independently represent —C (═O) O— or —C (═O) NR— (R represents a hydrogen atom or an alkyl group). X represents the following general formula (2) or general formula (3). }
General formula (2):

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represents a hydrogen atom or a substituent.)
General formula (3):

(In the formula, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represents a hydrogen atom or a substituent.)
[4]
A retardation increasing agent having a rod-shaped polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (4). The cellulose acylate film according to [1] or [2], which is a compound represented.
General formula (4)

^{(Wherein, R 2-1, R 4-1, R} 5-1 each represent a hydrogen atom or a ^{substituent, R 11-1,} R ^13-1 each represents a hydrogen atom or an alkyl ^{group, L 1- 1} and L ^2-1 each represent a single bond or a divalent linking group , Ar ^1-1 represents an arylene group or an aromatic heterocycle, and Ar ^2-1 represents an aryl group or an aromatic heterocycle. , n-1 represents an integer of 3 or more, n-1 or present ^{L 2-1, Ar 1-1} may each be the same or different. However ^{R 11-1, R 13-1} Are different from each other, and the alkyl group represented by R ^13-1 does not include a hetero atom.)
[5]
A retardation increasing agent having a rod-shaped polarizability anisotropy of 300 ×× 10 ⁻²⁵ cm ^{3 to} 2000 × 10 ⁻²⁵ cm ³ and a molecular end-to-end distance of 2 nm to 10 nm is represented by the following general formula (5): The cellulose acylate film according to [1] or [2], which is a compound represented by the formula:
General formula (5)

(In the formula, L ¹ and L ² each represent a single bond or a divalent linking group. R ¹ and R ² are each a hydrogen atom or a substituent. R ³ and R ⁴ are respectively Represents a substituent, and n represents an integer of 0 to 4, and when n is 2 or more, a plurality of R ³ may be the same or different, and may be bonded to each other to form a ring. m represents an integer of 0 to 4, and when m is 2 or more, a plurality of R ⁴ may be the same or different from each other, and if possible, may be bonded to each other to form a ring. ¹ represents an integer of ¹ to 5. When X ¹ is 2 or more, a plurality of (R ⁴ ) _m's may be the same or different, and R ⁴¹ represents a hydrogen atom or a substituent.
[6]
A retardation increasing agent having a plane polarizability anisotropy represented by the mathematical formula (2) of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less is The cellulose acylate film according to [1] or [2], which is a compound represented by the formula (6).
General formula (6):

(Wherein R ²¹ , R ²² and R ²³ each independently represents an alkyl group, an alkenyl group, an aromatic ring group or a heterocyclic group)
[7]
[1] A method for producing the cellulose acylate film according to any one of [6], wherein the cellulose acylate film is stretched at a stretch rate of 3% or more and 200% or less at a stretch rate of 100% or less per minute. A method for producing a cellulose acylate film, wherein the film is held for 1 second or more and 120 seconds or less at a draw ratio of 50% or more and 99% or less of the maximum draw ratio.
[8]
The cellulose acylate film according to any one of [1] to [6] produced by the method of [7].
[9]
In the polarizing plate in which protective films are bonded to both surfaces of the polarizer, at least one of the protective films is the cellulose acylate film according to any one of [1] to [6] and [8]. A polarizing plate characterized by that.
[10]
The polarizing plate according to [9], which has an optically anisotropic layer on at least one surface of the protective film.
[11]
The polarizing plate according to [9], wherein a retardation film is bonded to at least one surface of the protective film.
[12]
A liquid crystal display comprising a liquid crystal cell and two polarizing plates disposed on both sides thereof, at least one of the polarizing plates being a polarizing plate according to any one of [9] to [11] apparatus.
Although this invention is invention which concerns on said [1]-[12], below, other matters are also described.

1. The rod-shaped polarizability anisotropy represented by the following formula (1) is 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less, and the distance between the terminals of the molecule is 2 nm or more and 10 nm or less. A cellulose acylate film characterized by containing 0.1 wt% or more and 30 wt% or less of a retardation increasing agent.
Formula (1): Δα = α _x − (α _y + α _z ) / 2
(Where α _x is the largest component of eigenvalues obtained after diagonalizing the polarizability tensor; α _y is the second largest eigenvalue obtained after diagonalizing the polarizability tensor. Α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor.)

2. The plane polarizability anisotropy represented by the following formula (2) is 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less, and the end-to-end distance of the molecule is 2 nm or more and 10 nm or less. A cellulose acylate film comprising: 0.1 wt% or more and 30 wt% or less of a retardation increasing agent.
Formula (2): Δα = (α _x + α _y ) / 2−α _z
(Where α _x is the largest component of eigenvalues obtained after diagonalizing the polarizability tensor; α _y is the second largest eigenvalue obtained after diagonalizing the polarizability tensor. Α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor.)

3. At least one type of retardation increase in which the rod-like polarizability anisotropy represented by the following formula (1) is 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and the end-to-end distance is 2 nm or more and 10 nm or less. And at least one kind of agent having a plane polarizability anisotropy represented by the following formula (2) of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less. A cellulose acylate film comprising at least one retardation increasing agent in an amount of 0.1% by mass to 30% by mass with respect to cellulose acylate.
Formula (1): Δα = α _x − (α _y + α _z ) / 2
Formula (2): Δα = (α _x + α _y ) / 2−α _z
(Where α _x is the largest component of eigenvalues obtained after diagonalizing the polarizability tensor; α _y is the second largest eigenvalue obtained after diagonalizing the polarizability tensor. Α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor.)

4). Re and Rth at a wavelength of 590 nm are
20 ≦ Re ≦ 200
70 ≦ Rth ≦ 400
1 ≦ Rth / Re ≦ 10
The cellulose acylate film according to any one of Items 1 to 3, wherein (Re represents in-plane retardation, and Rth represents retardation in the thickness direction.)

5. A retardation increasing agent having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ^{3 to} 2000 × 10 ⁻²⁵ cm ³ and a molecular end-to-end distance of 2 nm to 10 nm is represented by the following general formula (1). The cellulose acylate film according to any one of Items 1, 3, and 4, which is a represented compound.
General formula (1):
Ar ¹ -L ¹ -XL ² -Ar ²
{In the formula, Ar ¹ and Ar ² each independently represents an aryl group or an aromatic heterocycle. L ¹ and L ² each independently represent —C (═O) O— or —C (═O) NR— (R represents a hydrogen atom or an alkyl group). X represents the following general formula (2) or general formula (3). }
General formula (2):

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represents a hydrogen atom or a substituent.)
General formula (3):

(In the formula, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represents a hydrogen atom or a substituent.)

（式中、Ｒ^2-1、Ｒ^4-1、Ｒ^5-1はそれぞれ水素原子または置換基を表し、Ｒ^11-1、Ｒ^13-1はそれぞれ水素原子またはアルキル基を表し、Ｌ^1-1、Ｌ^2-1はそれぞれ単結合または２価の連結基を表す。Ａｒ^1-1はアリーレン基または芳香族へテロ環を表し、Ａｒ^2-1はアリール基または芳香族へテロ環を表し、ｎ−１は３以上の整数を表し、ｎ−１種存在するＬ^2-1、Ａｒ^1-1はそれぞれ同一であっても異なっていてもよい。ただしＲ^11-1、Ｒ^13-1は互いに異なっており、Ｒ^13-1で表されるアルキル基はへテロ原子を含まない。）
７．棒状分極率異方性が３００×１０^-25ｃｍ³以上２０００××１０^-25ｃｍ³以下であり、分子の末端間距離が２ｎｍ以上１０ｎｍ以下のレターデーション上昇剤が、下記一般式（５）で表される化合物である第１、３および４項のいずれかに記載のセルロースアシレートフィルム。
一般式（５）

（式中、Ｌ¹およびＬ²は、それぞれ、単結合または二価の連結基を表す。Ｒ¹およびＲ²は、それぞれ、水素原子または置換基である。Ｒ³およびＲ⁴は、それぞれ、置換基を表す。ｎは０〜４の整数を表し、ｎが２以上の場合は、複数存在するＲ³はそれぞれ同じでも異なっていてもよく、可能であれば互いに結合して環を形成してもよい。ｍは０〜４の整数を表し、ｍが２以上の場合は、複数存在するＲ⁴はそれぞれ同じでも異なっていてもよく、互いに結合して環を形成してもよい。Ｘ¹は１〜５の整数を表す。Ｘ¹が２以上の場合は、複数存在する（Ｒ⁴）_mはそれぞれ同じでも異なっていてもよい。Ｒ⁴¹は水素原子または置換基を表す。）
８．数式（２）で表される平面分極率異方性が３００×１０^-25ｃｍ³以上１５００×１０^-25ｃｍ³以下で、末端間距離が２ｎｍ以上１０ｎｍ以下のレターデーション上昇剤が、下記一般式（４）で表される化合物である第２、３および４項のいずれかに記載のセルロースアシレートフィルム。
一般式（６）： 6). A retardation increasing agent having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 1000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (4). The cellulose acylate film according to any one of Items 1, 3, and 4, which is a represented compound.
General formula (4)

(Wherein R ^2-1 , R ^4-1 and R ^5-1 each represent a hydrogen atom or a substituent, R ^11-1 and R ^13-1 each represent a hydrogen atom or an alkyl group, and L ^{1- 1} and L ^2-1 each represents a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, and Ar ^2-1 represents an aryl group or an aromatic heterocyclic ring. , N-1 represents an integer of 3 or more, and L ^2-1 and Ar ^1-1 present in n-1 types may be the same or different, but R ^11-1 , R ^13-1 Are different from each other, and the alkyl group represented by R ^13-1 does not include a hetero atom.)
7). A retardation increasing agent having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 ×× 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (5): The cellulose acylate film according to any one of Items 1, 3, and 4, which is a compound represented by:
General formula (5)

(In the formula, L ¹ and L ² each represent a single bond or a divalent linking group. R ¹ and R ² are each a hydrogen atom or a substituent. R ³ and R ⁴ are each N represents an integer of 0 to 4, and when n is 2 or more, a plurality of R ³ may be the same or different from each other, and if possible, combine with each other to form a ring. M represents an integer of 0 to 4, and when m is 2 or more, a plurality of R ⁴ may be the same or different from each other, and may be bonded to each other to form a ring. ¹ represents an integer of ¹ to 5. When X ¹ is 2 or more, a plurality of (R ⁴ ) _m may be the same or different, and R ⁴¹ represents a hydrogen atom or a substituent.
8). A retardation increasing agent having a plane polarizability anisotropy represented by formula (2) of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less is The cellulose acylate film according to any one of Items 2, 3, and 4, which is a compound represented by Formula (4).
General formula (6):

(In the formula, R ²¹ , R ²² and R ²³ each independently represents an alkyl group, an alkenyl group, an aromatic ring group or a heterocyclic group.)

9. A method for producing a cellulose acylate film according to any one of items 1 to 8, wherein the cellulose acylate film is stretched at a stretching rate of 3% or more and 200% or less at a stretching rate of 100% or less per minute. After that, the method for producing a cellulose acylate film is characterized by holding at a draw ratio of 50% to 99% of the maximum draw ratio for 1 second to 120 seconds.
10. The cellulose acylate film according to any one of Items 1 to 8, which is produced by the method according to Item 9.

11. In the polarizing plate in which a protective film is bonded to both surfaces of a polarizer, at least one of the protective films is the cellulose acylate film according to any one of Items 1 to 8 and 10. Polarizing plate.
12 Item 12. The polarizing plate according to item 11, having an optically anisotropic layer on at least one surface of the protective film.
13. Item 12. The polarizing plate according to item 11, wherein a retardation film is bonded to at least one surface of the protective film.

14 A liquid crystal display device comprising a liquid crystal cell and two polarizing plates disposed on both sides thereof, wherein at least one polarizing plate is the polarizing plate according to any one of items 11 to 13.

  According to the present invention, it is possible to provide a cellulose acylate film having a desired retardation without causing a planar failure such as bleed out. Furthermore, by using the polarizing plate of the present invention using the cellulose acylate film for a liquid crystal display device, a liquid crystal display device having a wide viewing angle and high display quality can be provided.

<Cellulose acylate film>
[Retardation raising agent]
First, the retardation increasing agent used in the present invention will be described.
The end-to-end distance of the retardation increasing agent of the present invention needs to be 2 nm or more and 10 nm or less. When the end-to-end distance is smaller than the lower limit, the retardation increasing agent is difficult to align along the cellulose acylate molecular chain, and the polarizability anisotropy of the retardation increasing agent is not easily reflected in the retardation. On the other hand, if the end-to-end distance of the retardation increasing agent exceeds the upper limit, the retardation increasing agent becomes difficult to be compatible with cellulose acylate, and problems such as bleed out are likely to occur. I tend to. The end-to-end distance of the retardation increasing agent is preferably 2.5 nm or more and 8 nm or less.
The end-to-end distance can be determined from the optimized molecular structure by calculation using the molecular orbital method or the density functional method.

  The retardation increasing agents used in the present invention are roughly classified into two types. The first is a type in which the rod-shaped polarizability anisotropy of the molecule is large, and the second is a type in which the plane polarizability anisotropy of the molecule is large.

[Retardation increasing agent with large molecular rod-like polarizability anisotropy]
First, the type having a large molecular rod-like polarizability anisotropy will be described in detail.
The polarizability of the molecule can be determined by calculation using the molecular orbital method or the density functional method,
The rod-like polarizability anisotropy represented by the following mathematical formula (1) needs to be 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less. When the rod-shaped polarizability anisotropy is smaller than the lower limit, the retardation of the cellulose acylate is reduced. On the other hand, if the rod-like polarizability anisotropy exceeds the upper limit and is too large, the compatibility with the cellulose acylate deteriorates, and problems such as the tendency of the retardation increasing agent to bleed out tend to occur. . The rod-shaped polarizability anisotropy is preferably 350 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less.

Formula (1): Δα = α _x − (α _y + α _z ) / 2
(Where α _x is the largest component of the eigenvalues obtained after diagonalizing the polarizability tensor;
α _y is the second largest component of the eigenvalues obtained after diagonalizing the polarizability tensor;
α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor. )

The retardation increasing agent of the present invention having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula: The compound represented by (1) is particularly preferred.

Below, it demonstrates in detail regarding the compound represented by General formula (1).
General formula (1):
Ar ¹ -L ¹ -XL ² -Ar ²

{In the formula, Ar ¹ and Ar ² each independently represents an aryl group or an aromatic heterocycle. L ¹ and L ² each independently represent —C (═O) O— or —C (═O) NR— (R represents a hydrogen atom or an alkyl group). X represents the following general formula (2) or general formula (3). }
General formula (2):

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represents a hydrogen atom or a substituent.)
General formula (3):

(In the formula, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represents a hydrogen atom or a substituent.)

In general formula (1), Ar ¹ and Ar ² each independently represents an aryl group or an aromatic heterocycle. The aryl group represented by Ar ¹ or Ar ² is preferably an aryl group having 6 to 30 carbon atoms, and may be a single ring or may form a condensed ring with another ring. Further, if possible, it may have a substituent, and the substituent T described later can be applied as such a substituent.
More preferably, the aryl group represented by Ar ¹ and Ar ² has 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include phenyl, p-methylphenyl, and naphthyl.

In the general formula (1), the aromatic heterocycle represented by Ar ¹ or Ar ² may be any aromatic heterocycle containing at least one of an oxygen atom, a nitrogen atom or a sulfur atom, but is preferably Is a 5- to 6-membered aromatic heterocycle containing at least one of an oxygen atom, a nitrogen atom or a sulfur atom. Moreover, you may have a substituent further if possible. Substituent T described later can be applied as the substituent.

In the general formula (1), specific examples of the aromatic heterocycle represented by Ar ¹ and Ar ² include, for example, furan, pyrrole, thiophene, imidazole, pyrazole, pyridine, pyrazine, pyridazine, triazole, triazine, indole, Indazole, purine, thiazoline, thiazole, thiadiazole, oxazoline, oxazole, oxadiazole, quinoline, isoquinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzthiazole, Examples thereof include benzotriazole, tetrazaindene, pyrrolotriazole, and pyrazolotriazole. Preferred examples of the aromatic heterocycle include benzimidazole, benzoxazole, benzthiazole, and benzotriazole.

In the general formula (1), L ¹ and L ² each independently represent —C (═O) O— or —C (═O) NR— (R represents a hydrogen atom or an alkyl group), Both are equally preferred.
The alkyl group represented by R is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms. More preferably, R represents a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom.

In the general formula (2), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent a hydrogen atom or a substituent, and the substituent will be described later. The substituent T can be applied.
R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are preferably a hydrogen atom, an alkyl group, an amino group, an alkoxy group, a hydroxy group or a halogen atom, more preferably A hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxy group, and a halogen atom, more preferably a hydrogen atom, a methyl group, a methoxy group, a hydroxy group, a chlorine atom, and a fluorine atom. And particularly preferably a hydrogen atom or a fluorine atom, and most preferably a hydrogen atom.

In the general formula (3), R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a hydrogen atom or a substituent, and the substituent will be described later. The substituent T can be applied.
R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are preferably a hydrogen atom, an alkyl group, an amino group, an alkoxy group, a hydroxy group or a halogen atom, more preferably A hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxy group, and a halogen atom, more preferably a hydrogen atom, a methyl group, a methoxy group, a hydroxy group, a chlorine atom, and a fluorine atom. And particularly preferably a hydrogen atom or a fluorine atom, and most preferably a hydrogen atom.

Of the general formula (1), the general formula (1-1) is preferable.
General formula (1-1):

{Wherein R ¹¹¹ , R ¹¹² , R ¹¹³ , R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ , R ¹¹⁷ , R ¹¹⁸ , R ¹¹⁹ and R ¹²⁰ each independently represent a hydrogen atom or a substituent. L ₁ , L ₂ and X have the same meanings as those in the general formula (1), and preferred ranges are also the same. }

R ¹¹¹ and R ¹¹⁶ each independently represent a hydrogen atom or a substituent, preferably an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, more preferably an alkyl group having 1 to 4 carbon atoms or 1 carbon atom. And preferably an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms). And particularly preferred is a methoxy group.

R ¹¹² and R ¹¹⁷ each independently represents a hydrogen atom or a substituent, preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, and more preferably a hydrogen atom, an alkyl group, or an alkoxy group. And more preferably a hydrogen atom, an alkyl group (preferably having 1 to 4 carbon atoms, more preferably a methyl group), an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, More preferably, it is C1-C6, Most preferably, it is C1-C4. Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.

R ¹¹³ and R ¹¹⁸ each independently represents a hydrogen atom or a substituent, preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, more preferably an alkyl group or an alkoxy group, Preferably it is an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms). Most preferred are n-propoxy group, ethoxy group and methoxy group.

R ¹¹⁴ and R ¹¹⁹ each independently represent a hydrogen atom or a substituent, preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, and more preferably a hydrogen atom or a carbon number of 1 to 4 An alkyl group, an alkoxy group having 1 to 12 carbon atoms (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms); Particularly preferred are a hydrogen atom, an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms, and most preferred are a hydrogen atom, a methyl group and a methoxy group.

R ¹¹⁵ and R ¹²⁰ each independently represent a hydrogen atom or a substituent, preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, and more preferably a hydrogen atom, an alkyl group, or an alkoxy group. And more preferably a hydrogen atom, an alkyl group (preferably having a carbon number of 1-4, more preferably a methyl group), an alkoxy group (preferably having a carbon number of 1-12, more preferably having a carbon number of 1-8, further Preferably it is C1-C6, Most preferably, it is C1-C4. Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.

Of the general formula (1), the general formula (1-2) is more preferable.
General formula (1-2):

{In the formula, R ¹¹¹ , R ¹¹² , R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ , R ¹¹⁷ , R ¹¹⁸ , R ¹¹⁹ , R ¹²⁰ , L ¹ , L ^2, and X are each in the general formula (1-1) They are synonymous with them, and preferred ranges are also the same. R ¹²¹ represents an alkyl group having 1 to 12 carbon atoms. }

In the general formula (1-2), R ¹²¹ represents an alkyl group having 1 to 12 carbon atoms, and the alkyl group may be linear or branched, and may further have a substituent. Is an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms, still more preferably an alkyl group having 1 to 6 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms (for example, methyl group, ethyl group) Group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group and the like).

Of the general formula (1), the general formula (1-3) is more preferable.
General formula (1-3):

{In the formula, R ¹¹² , R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ , R ¹¹⁷ , R ¹¹⁸ , R ¹¹⁹ , R ¹²⁰ , R ¹²¹ , L ¹ , L ^2, and X are each in the above general formula (1-2) They are synonymous with them, and preferred ranges are also the same. R ¹²² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. }

R ¹²² is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, still more preferably a hydrogen atom or a methyl group, particularly preferably a methyl group. It is.

Of the general formula (1), the general formula (1-4) is particularly preferable.
General formula (1-4):

{In the formula, R ¹¹² , R ¹¹⁵ , R ¹¹⁶ , R ¹¹⁷ , R ¹¹⁸ , R ¹¹⁹ , R ¹²⁰ , R ¹²¹ , R ¹²² , L ¹ , L ^2, and X are each in the above general formula (1-3) They are synonymous with them, and preferred ranges are also the same. R ¹²³ represents an alkyl group having 1 to 4 carbon atoms. }

R ¹²³ is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group, and still more preferably a methyl group.

The aforementioned substituent T will be described below.
Examples of the substituent T include an alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as methyl, ethyl, i-propyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, etc.), an alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 carbon atoms). -8, for example, vinyl, allyl, 2-butenyl, 3-pentenyl and the like, alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 2 carbon atoms). 8 such as propargyl and 3-pentynyl), an aryl group (preferably having 6 to 30 carbon atoms, more preferably A prime number of 6 to 20, particularly preferably a carbon number of 6 to 12, for example, phenyl, p-methylphenyl, naphthyl and the like, a substituted or unsubstituted amino group (preferably having a carbon number of 0 to 20, more preferably The number of carbon atoms is 0 to 10, particularly preferably 0 to 6, and examples thereof include amino, methylamino, dimethylamino, diethylamino, dibenzylamino, and the like, and alkoxy groups (preferably having 1 to 20 carbon atoms, more preferably Has 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, and examples thereof include methoxy, ethoxy, butoxy and the like, an aryloxy group (preferably 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms). Particularly preferably 6 to 12 carbon atoms such as phenyloxy and 2-naphthyloxy), acyl groups ( Preferably it has 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include acetyl, benzoyl, formyl, pivaloyl and the like, alkoxycarbonyl group (preferably carbon 2 to 20, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, etc.), an aryloxycarbonyl group (preferably having 7 to 20 carbon atoms, More preferably, it has 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms, and examples thereof include phenyloxycarbonyl and the like, an acyloxy group (preferably 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, Particularly preferably, it has 2 to 10 carbon atoms, and examples thereof include acetoxy and benzoyloxy. ), An acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms such as acetylamino and benzoylamino), an alkoxycarbonylamino group ( Preferably they are C2-C20, More preferably, it is C2-C16, Most preferably, it is C2-C12, for example, methoxycarbonylamino etc. are mentioned, Aryloxycarbonylamino group (preferably C7-C7) 20, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonylamino, and sulfonylamino groups (preferably 1 to 20 carbon atoms, more preferably carbon atoms). 1 to 16, particularly preferably 1 to 12 carbon atoms, such as methanesulfonylamino, And sulfamoyl groups (preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms, such as sulfamoyl, methylsulfamoyl, A carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms. For example, carbamoyl, methylcarbamoyl, Examples thereof include diethylcarbamoyl and phenylcarbamoyl. ), An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms such as methylthio and ethylthio), an arylthio group (preferably having carbon number) 6 to 20, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenylthio, and a sulfonyl group (preferably 1 to 20 carbon atoms, more preferably 1 to carbon atoms). 16, particularly preferably 1 to 12 carbon atoms, such as mesyl and tosyl), sulfinyl groups (preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 1 carbon atoms). 12 such as methanesulfinyl, benzenesulfinyl, etc.), ureido group (preferably having 1 to 20 carbon atoms) Preferably it is C1-C16, Most preferably, it is C1-C12, for example, ureido, methylureido, phenylureido etc. are mentioned, Phosphate amide group (preferably C1-C20, More preferably carbon 1 to 16, particularly preferably 1 to 12 carbon atoms, such as diethyl phosphoric acid amide and phenyl phosphoric acid amide), hydroxy group, mercapto group, halogen atom (for example, fluorine atom, chlorine atom, bromine atom) , Iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, heterocyclic group (preferably having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms). A hetero atom such as a nitrogen atom, an oxygen atom, or a sulfur atom; specifically, for example, imidazolyl or pyridyl Quinolyl, furyl, piperidyl, morpholino, benzoxazolyl, benzimidazolyl, benzthiazolyl and the like, silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, and particularly preferably carbon number) 3 to 24, and examples thereof include trimethylsilyl and triphenylsilyl). These substituents may be further substituted.

  Moreover, when there are two or more substituents, they may be the same or different. If possible, they may be linked together to form a ring.

  Hereinafter, the compound represented by the general formula (1) will be described in detail with specific examples, but the present invention is not limited to the following specific examples.

The compounds represented by the general formulas (1) to (1-4) of the present invention can be synthesized by a general esterification reaction or amidation reaction of a substituted benzoic acid and a phenol or aniline derivative. Any reaction may be used. Examples thereof include a method of converting a substituted benzoic acid into an acid halide and then condensing it with a phenol or aniline derivative, a method of dehydrating a substituted benzoic acid and a phenol or aniline derivative using a condensing agent or a catalyst, and the like. In view of the production process and the like, a method in which a substituted benzoic acid is functionally converted to an acid halide and then condensed with a phenol or aniline derivative is preferable.

  As the reaction solvent, hydrocarbon solvents (preferably toluene, xylene), ether solvents (preferably dimethyl ether, tetrahydrofuran, dioxane, etc.), ketone solvents, ester solvents, acetonitrile, dimethylformamide, dimethylacetamide, etc. should be used. Can do. These solvents may be used alone or in admixture of several kinds, and preferred reaction solvents are toluene, acetonitrile, dimethylformamide and dimethylacetamide.

  The reaction temperature is preferably 0 to 150 ° C, more preferably 0 to 100 ° C, still more preferably 0 to 90 ° C, and particularly preferably 20 ° C to 90 ° C.

  In this reaction, it is preferable not to use a base. When a base is used, either an organic base or an inorganic base may be used, preferably an organic base such as pyridine, tertiary alkylamine (preferably triethylamine, ethyldiisopropyl). Pyramine, etc.).

The retardation increasing agent of the present invention having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ^{3 to} 2000 × 10 ⁻²⁵ cm ³ and a molecular end-to-end distance of 2 nm to 10 nm is represented by the following general formula: The compound represented by (4) is also particularly preferable.
Hereinafter, the compound of the general formula (4) will be described in detail.
General formula (4)

(In the general formula (4), R ^2-1 , R ^4-1 and R ^5-1 each represent a hydrogen atom or a substituent, and R ^11-1 and R ^13-1 each represent a hydrogen atom or an alkyl group. , L ^1-1 and L ^2-1 each represent a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, and Ar ^2-1 represents an aryl group or an aromatic group. Represents a terror ring, and n-1 represents an integer of 3 or more, and L ^2-1 and Ar ^1-1 present in n-1 types may be the same or different, provided that R ^11-1 , R ^13-1 is different from each other, and the alkyl group represented by R ^13-1 does not contain a hetero atom.)
In the general formula ^{(4), R 2-1, R} 4-1, R 5-1 each represent a hydrogen atom or a substituent, the substituents may be the substituent T ² of the later.

^R2-1 is preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group or a hydroxyl group, more preferably a hydrogen atom, an alkyl group or an alkoxy group, still more preferably a hydrogen atom or an alkyl group (preferably 1 to 4 carbon atoms, more preferably a methyl group), an alkoxy group (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly Preferably it is C1-C4. Particularly preferred are a hydrogen atom, a methyl group and a methoxy group, and most preferred is a hydrogen atom.

^R4-1 is preferably a hydrogen atom or an electron donating group, more preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, and still more preferably a hydrogen atom or a carbon atom number of 1 to 4. And preferably an alkoxy group having 1 to 12 carbon atoms (preferably 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, and further preferably 1 to 4 carbon atoms). Is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, and most preferably a hydrogen atom or a methoxy group.

^R5-1 is preferably a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, more preferably a hydrogen atom, an alkyl group, or an alkoxy group, still more preferably a hydrogen atom, an alkyl group. (Preferably 1 to 4 carbon atoms, more preferably a methyl group), an alkoxy group (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms). Particularly preferred is C 1-4). Particularly preferred are a hydrogen atom, a methyl group and a methoxy group. Most preferably, it is a hydrogen atom.

R ^11-1 and R ^13-1 each represent a hydrogen atom or an alkyl group, R ^11-1 and R ^13-1 are different from each other, and the alkyl group represented by R ^13-1 represents a ^hetero atom. Not included. Here, the heteroatom means an atom other than a hydrogen atom or a carbon atom, such as an oxygen atom, nitrogen atom, sulfur atom, phosphorus, silicon, halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), boron, etc. Is mentioned.
The alkyl groups represented by R ^11-1 and R ^13-1 each represent a linear, branched, or cyclic alkyl group that is substituted or unsubstituted, preferably a substituted or unsubstituted carbon atom. An alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms (that is, a bicyclocarbon having 5 to 30 carbon atoms). A monovalent group in which one hydrogen atom is removed from an alkane.), And a tricyclo structure having many ring structures.

Preferred examples of the alkyl group represented by R ^11-1 and R ^13-1 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, and tert-butyl, respectively. Group, n-pentyl group, iso-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, tert-octyl group, 2-ethylhexyl group, n-nonyl group, 1,1,3-trimethylhexyl Group, n-decyl group, 2-hexyldecyl group, cyclohexyl group, cycloheptyl group, 2-hexenyl group, oleyl group, linoleyl group, linolenyl group and the like. Examples of the cycloalkyl group include a cyclohexyl group, a cyclopentyl group, a 4-n-dodecylcyclohexyl group, and a bicycloalkyl group as a bicyclo [1,2,2] heptan-2-yl group and a bicyclo [2,2,2 ] An octan-3-yl group can be mentioned.

R ^11-1 is more preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group, particularly preferably a hydrogen atom or a methyl group, and most preferably a methyl group.
R ^13-1 is particularly preferably an alkyl group containing 2 or more carbon atoms, and more preferably an alkyl group containing 3 or more carbon atoms.

Hereinafter, specific examples of the alkyl group represented by R ^13-1 will be described. However, the present invention is not limited to the following specific examples.

  In the above examples, # means the side bonded to the oxygen atom.

Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, and Ar ^1-1 in the repeating unit may all be the same or different. Ar ^2-1 represents an aryl group or an aromatic heterocyclic ring.
In general formula (4), the arylene group represented by Ar ^1-1 preferably has 6 to 3 carbon atoms.
0 arylene group, which may be a single ring or may form a condensed ring with another ring. Further, if possible, it may have a substituent, and the substituent T ² described later can be applied as the substituent. The arylene group represented by Ar ^1-1 preferably has 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include a phenylene group, a p-methylphenylene group, and a naphthylene group.
In general formula (4), the aryl group represented by Ar ^2-1 is preferably an aryl group having 6 to 30 carbon atoms, which may be a single ring or further forms a condensed ring with another ring. May be. Further, if possible, it may have a substituent, and the substituent T ² described later can be applied as the substituent. The aryl group represented by Ar ^2-1 preferably has 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include a phenyl group, a p-methylphenyl group, and a naphthalene group.

In the general formula (4), the aromatic heterocycle represented by Ar ^1-1 or Ar ^2-1 is preferably an aromatic heterocycle containing at least one of an oxygen atom, a nitrogen atom or a sulfur atom, More preferably, it is an aromatic heterocycle containing at least one of a 5- to 6-membered oxygen atom, nitrogen atom or sulfur atom. Moreover, you may have a substituent further if possible. As the substituent, a substituent T ² described later can be applied.

In the general formula (4), specific examples of the aromatic heterocycle represented by Ar ^1-1 and Ar ^2-1 include, for example, a furan ring, a pyrrole ring, a thiophene ring, an imidazole ring, a pyrazole ring, a pyridine ring, Pyrazine ring, pyridazine ring, triazole ring, triazine ring, indole ring, indazole ring, purine ring, thiazoline ring, thiazole ring, thiadiazole ring, oxazoline ring, oxazole ring, oxadiazole ring, quinoline ring, isoquinoline ring, phthalazine ring, Naphthyridine ring, quinoxaline ring, quinazoline ring, cinnoline ring, pteridine ring, acridine ring, phenanthroline ring, phenazine ring, tetrazole ring, benzimidazole ring, benzoxazole ring, benzthiazole ring, benzotriazole ring, tetrazaindene ring, pyrrolotriazole Ring, pyra Such as Rotoriazoru ring, and the like. Preferred as the aromatic heterocycle are a benzimidazole ring, a benzoxazole ring, a benzthiazole ring, and a benzotriazole ring.

In General Formula (4), L ^1-1 and L ^2-1 each represent a single bond or a divalent linking group. L ^1-1 and L ^2-1 may be the same or different. Further, all L ^2-1 in the repeating unit may be the same or different.
Preferred as the divalent linking group is —O—, —NR ^1-1 — (R ^1-1 represents a hydrogen atom or an optionally substituted alkyl group or aryl group), —CO—, —SO ₂ —, —S—, an alkylene group, a substituted alkylene group, an alkenylene group, a substituted alkenylene group, an alkynylene group, and a group obtained by combining two or more of these divalent groups, more preferably among them. -O -, - NR -, - CO -, - SO 2 NR 1-1 -, - NR 1-1 SO 2 -, - CONR 1-1 -, - NR 1-1 CO -, - COO-, and -OCO-, an alkynylene group. R ^1-1 preferably represents a hydrogen atom.

In the compound represented by the general formula (4) in the present invention, Ar ^1-1 is bonded to L ^1-1 and L ^2-1 , but when Ar ^1-1 is a phenylene group, -L ^1-1 -Ar ^1-1 -L ^2-1 -, and -L ^2-1 -Ar ^1-1 -L ^2-1 - it is most preferable that a relation of mutually para position (1,4-position).

  In general formula (4), n-1 represents an integer greater than or equal to 3, Preferably it is 3-7, More preferably, it is 3-7, More preferably, it is 3-6.

Among the compounds of the general formula (4), compounds represented by the following general formula (4-2) or general formula (4-3) can be particularly preferably used.
Formula (4-2)

(In General Formula (4-2), R ^2-1 and R ^5-1 each represent a hydrogen atom or a substituent, R ^11-1 and R ^13-1 each represent a hydrogen atom or an alkyl group, L ^1-1 and L ^2-1 each represent a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, and Ar ^2-1 represents an aryl group or an aromatic group. Represents a terror ring, n-1 represents an integer of 3 or more, and L ^2-1 and Ar ^1-1 present in n-1 types may be the same or different, provided that R ^11-1 and R ^13-1 is different from each other, and the alkyl group represented by R ^13-1 does not contain a hetero atom.)

In the general formula (4-2), R ^2-1 , R ^5-1 , R ^11-1 and R ^13-1 have the same ^{meanings as} those in the general formula (4), and preferred ranges are also the same. ^{Further, L 1-1, L 2-1, Ar} 1-1, Ar 2-1 has the same meaning as those in formula (4), and preferred ranges are also the same.
Formula (4-3)

(In the general formula (4-3), R ^2-1 and R ^5-1 each represent a hydrogen atom or a substituent, and R ^11-1 , R ^13-1 and R ^14-1 each represent a hydrogen atom or an alkyl. L ^1-1 and L ^2-1 each represent a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, and Ar ^2-1 represents an aryl group or Represents an aromatic heterocyclic ring, n-1 represents an integer of 3 or more, and L ^2-1 and Ar ^1-1 present in n-1 types may be the same or different, but R ^{11 -1} and R ^13-1 are different from each other, and the alkyl group represented by R ^13-1 does not contain a hetero atom.)

In general formula (4-3), R ^2-1 , R ^5-1 , R ^11-1 and R ^13-1 have the same ^{meanings as} those in general formula (4), and preferred ranges are also the same. ^{Further, L 1-1, L 2-1, Ar} 1-1, Ar 2-1 has the same meaning as those in formula (4), and preferred ranges are also the same.
R ^14-1 represents a hydrogen atom or an alkyl group. As the alkyl group, alkyl groups shown as preferred examples of R ^11-1 and R ^13-1 are preferably used. R ^14-1 more preferably represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group. . R ^11-1 and R ^14-1 may be the same or different, but both are particularly preferably methyl groups.

Moreover, the compound represented by general formula (4-4) or general formula (4-5) is also preferable.
Formula (4-4)

(In General Formula (4-4), R ^2-1 and R ^5-1 each represent a hydrogen atom or a substituent, R ^11-1 and R ^13-1 each represent a hydrogen atom or an alkyl group, and L ^{1 -1} and L ^2-1 each represent a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, n-1 represents an integer of 3 or more, and n-1 Species present L ^1-1 and Ar ^1-1 may be the same or different, provided that R ^11-1 and R ^13-1 are different from each other, and alkyl represented by R ^13-1 The group does not contain a heteroatom.)
In the general formula ^{(4-4), R 2-1, R} 5-1, R 11-1, R 13-1, L 1-1, L 2-1, Ar 1-1, n-1 is the general formula It is synonymous with those in (4), and the preferred range is also the same.

Formula (4-5)

(In the general formula (4-5), R ^2-1 and R ^5-1 each represent a hydrogen atom or a substituent, and R ^11-1 , R ^13-1 and R ^14-1 represent a hydrogen atom or an alkyl group, respectively. L ^1-1 and L ^2-1 each represent a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocyclic ring, and n-1 represents an integer of 3 or more. And L ^1-1 and Ar ^2-1 present in n-1 species may be the same or different, provided that R ^11-1 and R ^13-1 are different from each other, and R ^13-1 (The alkyl group represented by does not contain a hetero atom.)

In the general formula ^{(4-5), R 2-1, R} 5-1, R 11-1, R 13-1, L 1-1, L 2-1, Ar 1-1, n-1 is the general formula It is synonymous with those in (4), and the preferred range is also the same.
R ^14-1 has the same meaning as R ^14-1 in formula (4-3), and the preferred range is also the same.

The aforementioned substituent T ² will be described below.
Examples of the substituent T ² include a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), an alkyl group (preferably an alkyl group having 1 to 30 carbon atoms, for example, a methyl group, an ethyl group, n- A propyl group, an isopropyl group, a tert-butyl group, an n-octyl group, a 2-ethylhexyl group), a cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, such as a cyclohexyl group, A hydrogen atom from a cyclopentyl group, 4-n-dodecylcyclohexyl group), a bicycloalkyl group (preferably a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms, that is, a bicycloalkane having 5 to 30 carbon atoms). A monovalent group removed, for example, a bicyclo [1,2,2] heptan-2-yl group, B [2,2,2] octane-3-yl group), alkenyl group (preferably a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, such as vinyl group, allyl group), cycloalkenyl group (preferably Is a substituted or unsubstituted cycloalkenyl group having 3 to 30 carbon atoms, that is, a monovalent group obtained by removing one hydrogen atom of a cycloalkene having 3 to 30 carbon atoms, for example, 2-cyclopentene-1 -Yl group, 2-cyclohexen-1-yl group), bicycloalkenyl group (substituted or unsubstituted bicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, that is, a double bond A monovalent group obtained by removing one hydrogen atom from a bicycloalkene having, for example, bicyclo [2,2,1] hept-2-en-1-yl Group, bicyclo [2,2,2] oct-2-en-4-yl group), alkynyl group (preferably a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, for example, ethynyl group, propargyl group ), An aryl group (preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, such as a phenyl group, a p-tolyl group, a naphthyl group), a heterocyclic group (preferably a 5- or 6-membered substituted or unsubstituted group) A monovalent group obtained by removing one hydrogen atom from an aromatic or non-aromatic heterocyclic compound, more preferably a 5- or 6-membered aromatic heterocyclic group having 3 to 30 carbon atoms. For example, 2-furyl group, 2-thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group), cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group (preferably A substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, for example, a methoxy group, an ethoxy group, an isopropoxy group, a tert-butoxy group, an n-octyloxy group, a 2-methoxyethoxy group), an aryloxy group ( Preferably, it is a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, such as phenoxy group, 2-methylphenoxy group, 4-tert-butylphenoxy group, 3-nitrophenoxy group, 2-tetradecanoylamino. Phenoxy group), a silyloxy group (preferably a silyloxy group having 3 to 20 carbon atoms, such as trimethylsilyloxy group, tert-butyldimethylsilyloxy group), a heterocyclic oxy group (preferably having 2 to 30 carbon atoms) Substituted or unsubstituted heterocyclic oxy group, 1-phenyltetrazole-5-o Si group, 2-tetrahydropyranyloxy group), acyloxy group (preferably formyloxy group, substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, substituted or unsubstituted group having 6 to 30 carbon atoms) Arylcarbonyloxy groups, for example, formyloxy group, acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group), carbamoyloxy group (preferably having 1 to 30 carbon atoms) Or an unsubstituted carbamoyloxy group, for example, N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyloxy group, morpholinocarbonyloxy group, N, N-di-n-octylaminocarbonyloxy group, Nn -Octylcarbamoyloxy group), a Lucoxycarbonyloxy group (preferably a substituted or unsubstituted alkoxycarbonyloxy group having 2 to 30 carbon atoms, for example, methoxycarbonyloxy group, ethoxycarbonyloxy group, tert-butoxycarbonyloxy group, n-octylcarbonyloxy group) An aryloxycarbonyloxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy group having 7 to 30 carbon atoms such as phenoxycarbonyloxy group, p-methoxyphenoxycarbonyloxy group, pn-hexadecyloxy A phenoxycarbonyloxy group), an amino group (preferably an amino group, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, a substituted or unsubstituted anilino group having 6 to 30 carbon atoms, such as an amino group , Methylamino group Dimethylamino group, anilino group, N-methyl-anilino group, diphenylamino group), acylamino group (preferably formylamino group, substituted or unsubstituted alkylcarbonylamino group having 1 to 30 carbon atoms, carbon number 6 -30 substituted or unsubstituted arylcarbonylamino groups such as formylamino group, acetylamino group, pivaloylamino group, lauroylamino group, benzoylamino group), aminocarbonylamino group (preferably having 1 to 30 carbon atoms) A substituted or unsubstituted aminocarbonylamino group, such as a carbamoylamino group, an N, N-dimethylaminocarbonylamino group, an N, N-diethylaminocarbonylamino group, a morpholinocarbonylamino group, an alkoxycarbonylamino group (preferably a carbon atom) Number 2-3 Substituted or unsubstituted alkoxycarbonylamino groups such as methoxycarbonylamino group, ethoxycarbonylamino group, tert-butoxycarbonylamino group, n-octadecyloxycarbonylamino group, N-methyl-methoxycarbonylamino group), aryloxycarbonyl An amino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms, such as a phenoxycarbonylamino group, a p-chlorophenoxycarbonylamino group, or an mn-octyloxyphenoxycarbonylamino group) , Sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms, such as sulfamoylamino group, N, N-dimethylaminosulfonylamino group, Nn- Oh Tilaminosulfonylamino group), alkyl and arylsulfonylamino groups (preferably substituted or unsubstituted alkylsulfonylamino having 1 to 30 carbon atoms, substituted or unsubstituted arylsulfonylamino groups having 6 to 30 carbon atoms, for example, , Methylsulfonylamino group, butylsulfonylamino group, phenylsulfonylamino group, 2,3,5-trichlorophenylsulfonylamino group, p-methylphenylsulfonylamino group), mercapto group, alkylthio group (preferably having 1 carbon atom) -30 substituted or unsubstituted alkylthio groups such as methylthio group, ethylthio group, n-hexadecylthio group), arylthio groups (preferably substituted or unsubstituted arylthio groups having 6 to 30 carbon atoms such as phenylthio group, p -Chlorofe Nylthio group, m-methoxyphenylthio group), heterocyclic thio group (preferably a substituted or unsubstituted heterocyclic thio group having 2 to 30 carbon atoms, such as 2-benzothiazolylthio group, 1-phenyltetrazole- 5-ylthio group), a sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms, for example, N-ethylsulfamoyl group, N- (3-dodecyloxypropyl) sulfamoyl group, N, N-dimethylsulfamoyl group, N-acetylsulfamoyl group, N-benzoylsulfamoyl group, N- (N′phenylcarbamoyl) sulfamoyl group), sulfo group, alkyl and arylsulfinyl group (preferably carbon atom) A substituted or unsubstituted alkylsulfinyl group of 1 to 30; a substituted or unsubstituted group of 6 to 30 Substituted arylsulfinyl groups such as methylsulfinyl group, ethylsulfinyl group, phenylsulfinyl group, p-methylphenylsulfinyl group), alkyl and arylsulfonyl groups (preferably substituted or unsubstituted alkyl having 1 to 30 carbon atoms) A sulfonyl group, a 6-30 substituted or unsubstituted arylsulfonyl group, for example, a methylsulfonyl group, an ethylsulfonyl group, a phenylsulfonyl group, a p-methylphenylsulfonyl group, an acyl group (preferably a formyl group, 2 carbon atoms) -30 substituted or unsubstituted alkylcarbonyl group, substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, such as acetyl group and pivaloylbenzoyl group, aryloxycarbonyl group (preferably carbon atom) Replace the number 7-30 Is an unsubstituted aryloxycarbonyl group, for example, phenoxycarbonyl group, o-chlorophenoxycarbonyl group, m-nitrophenoxycarbonyl group, p-tert-butylphenoxycarbonyl group), alkoxycarbonyl group (preferably having 2 carbon atoms) -30 substituted or unsubstituted alkoxycarbonyl groups such as methoxycarbonyl group, ethoxycarbonyl group, tert-butoxycarbonyl group, n-octadecyloxycarbonyl group), carbamoyl group (preferably substituted with 1 to 30 carbon atoms or Unsubstituted carbamoyl groups such as carbamoyl group, N-methylcarbamoyl group, N, N-dimethylcarbamoyl group, N, N-di-n-octylcarbamoyl group, N- (methylsulfonyl) carbamoyl group), aryl and Borocyclic azo group (preferably substituted or unsubstituted arylazo group having 6 to 30 carbon atoms, substituted or unsubstituted heterocyclic azo group having 3 to 30 carbon atoms, such as phenylazo group, p-chlorophenylazo group, 5-ethylthio-1,3,4-thiadiazol-2-ylazo group), imide group (preferably N-succinimide group, N-phthalimide group), phosphino group (preferably substituted with 2 to 30 carbon atoms or Unsubstituted phosphino group such as dimethylphosphino group, diphenylphosphino group, methylphenoxyphosphino group), phosphinyl group (preferably a substituted or unsubstituted phosphinyl group having 2 to 30 carbon atoms such as phosphinyl group , Dioctyloxyphosphinyl group, diethoxyphosphinyl group), phosphinyloxy group (preferred Or a substituted or unsubstituted phosphinyloxy group having 2 to 30 carbon atoms, such as a diphenoxyphosphinyloxy group or a dioctyloxyphosphinyloxy group, or a phosphinylamino group (preferably a carbon A substituted or unsubstituted phosphinylamino group having 2 to 30 atoms, such as a dimethoxyphosphinylamino group or a dimethylaminophosphinylamino group, a silyl group (preferably a substituted or substituted group having 3 to 30 carbon atoms) An unsubstituted silyl group such as a trimethylsilyl group, a tert-butyldimethylsilyl group, and a phenyldimethylsilyl group).

  Among the above-mentioned substituents, those having a hydrogen atom may be substituted with the above-mentioned group after removing this. Examples of such functional groups include an alkylcarbonylaminosulfonyl group, an arylcarbonylaminosulfonyl group, an alkylsulfonylaminocarbonyl group, and an arylsulfonylaminocarbonyl group. Examples thereof include a methylsulfonylaminocarbonyl group, a p-methylphenylsulfonylaminocarbonyl group, an acetylaminosulfonyl group, and a benzoylaminosulfonyl group.

  Moreover, when there are two or more substituents, they may be the same or different. If possible, they may be linked together to form a ring.

As a preferable compound represented by the general formula (4-4) or (4-5), R ^11-1 is a methyl group, R ^2-1 and R ^5-1 are both hydrogen atoms, R ¹³ is an alkyl group having 3 or more carbon atoms, and L ^1-1 and L ^2-1 are each a single bond, —O—, —CO—, —NR—, —SO ₂ NR—, — _{NRSO 2 -, - CONR -,} - NRCO -, - COO -, -. OCO- and alkynylene groups (R is a hydrogen atom, an alkyl group which may have a substituent, an aryl group is preferably a hydrogen atom )), Ar ^1-1 is an arylene group, and n-1 is 3-6.

  Hereinafter, the compound represented by the general formula (4) will be described in detail with specific examples, but the present invention is not limited to the following specific examples.

The compound represented by the general formula (4) can be synthesized by first synthesizing a substituted benzoic acid, followed by a general ester reaction or amidation reaction between the substituted benzoic acid and a phenol derivative or aniline derivative. Any reaction may be used as long as it is a formation reaction. For example, a method in which a substituted benzoic acid is functionally converted to an acid halide and then condensed with a phenol derivative or aniline derivative, a method in which a substituted benzoic acid and a phenol derivative or aniline derivative are subjected to dehydration condensation using a condensing agent or catalyst, etc. It is done.
As a method for producing the compound represented by the general formula (4), a method in which a substituted benzoic acid is functionally converted to an acid halide and then condensed with a phenol derivative or an aniline derivative is preferable in consideration of the production process and the like.

  In the method for producing the compound represented by the general formula (4), examples of the reaction solvent include hydrocarbon solvents (preferably toluene and xylene), ether solvents (preferably dimethyl ether, tetrahydrofuran, dioxane and the like). ), Ketone solvents, ester solvents, acetonitrile, dimethylformamide, dimethylacetamide, and the like. These solvents may be used alone or in admixture of several kinds, and the solvent is preferably toluene, acetonitrile, dimethylformamide, or dimethylacetamide.

The reaction temperature is preferably 0 to 150 ° C, more preferably 0 to 100 ° C, still more preferably 0 to 90 ° C, and particularly preferably 20 ° C to 90 ° C.
Moreover, it is preferable not to use a base for this reaction. When a base is used, it may be either an organic base or an inorganic base, preferably an organic base, such as pyridine or tertiary alkylamine (preferably triethylamine, ethyldiisopropylamine, etc.).

  The compound represented by the general formula (4-4) or the general formula (4-5) can be synthesized by a known method. For example, when n-1 is 4, the following structural formula (7 ) Is subjected to a reaction with a derivative having a reactive site such as a hydroxyl group or an amino group to obtain an intermediate represented by the following structural formula (8). The compound having (9) can be obtained by linking by one molecule. However, the synthesis method of the compound in the present invention is not limited to this example.

  Structural formula (7)

(Wherein A ^1-1 represents a reactive group such as a hydroxyl group or a halogen atom, and R ^11-1 , R ^2-1 , R ^13-1 , and R ^5-1 are as described above, R ^4-1 is a hydrogen atom or a substituent represented by the aforementioned OR ^14-1 .)

  Structural formula (8)

(In the formula, A ′ ^1-1 represents a reactive group such as a carboxyl group, and R ^11-1 , R ^2-1 , R ^13-1 , R ^4-1 , R ^5-1 , Ar ^1-1 , And L ^1-1 is as described above.)

  Structural formula (9)

(In the formula, B ^1-1 and B ′ ^1-1 represent a reactive group such as a hydroxyl group and an amino group, and Ar ^2-1 and L ^2-1 represent Ar ^1-1 and L ^2-1 described above, respectively. Is synonymous with.)

The retardation increasing agent of the present invention having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula: The compound represented by (5) is also particularly preferable.
Hereinafter, the compound of the formula (5) will be described in detail.

  General formula (5)

In General Formula (5), L ¹ and L ² each represent a single bond or a divalent linking group.
Specific examples of the divalent linking group include, for example, —NR ⁸ — (R ⁸ represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, A hydrogen atom is preferred), —SO ₂ —, —CO—, a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkenylene group, an alkynylene group, a substituted or unsubstituted phenylene group, substituted or unsubstituted A substituted biphenylene group, a substituted or unsubstituted naphthalene group, —O—, —S—, —SO—, and a group obtained by combining two or more thereof. More preferably, L ¹ and L ² are each a single bond, —NR ⁸ —, —O—, or —S—, more preferably a single bond or —NR ⁸ —, and most preferably —NR ^{8. 8} −.

In General Formula (5), R ¹ and R ² are each a hydrogen atom or a substituent. The following can be applied as examples of the substituent.

A halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group (preferably an alkyl group having 1 to 30 carbon atoms, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a tert- Butyl group, n-octyl group, 2-ethylhexyl group), cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms such as cyclohexyl group, cyclopentyl group, 4-n-dodecylcyclohexyl) Group), a bicycloalkyl group (preferably a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms, that is, a monovalent group obtained by removing one hydrogen atom from a bicycloalkane having 5 to 30 carbon atoms. , Bicyclo [1,2,2] heptan-2-yl, bicyclo [2,2,2] octane-3-yl), a A kenyl group (preferably a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, such as a vinyl group or an allyl group), a cycloalkenyl group (preferably a substituted or unsubstituted cycloalkenyl group having 3 to 30 carbon atoms, That is, it is a monovalent group in which one hydrogen atom of a cycloalkene having 3 to 30 carbon atoms is removed, for example, a 2-cyclopenten-1-yl, 2-cyclohexen-1-yl group), a bicycloalkenyl group (substituted or substituted). An unsubstituted bicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, that is, a monovalent group in which one hydrogen atom of a bicycloalkene having one double bond is removed. Bicyclo [2,2,1] hept-2-en-1-yl group, bicyclo [2,2,2] oct-2-en-4-yl group), a A quinyl group (preferably a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, such as an ethynyl group or a propargyl group), an aryl group (preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, such as phenyl Group, p-tolyl group, naphthyl group), heterocyclic group (preferably a monovalent group obtained by removing one hydrogen atom from a 5- or 6-membered substituted or unsubstituted aromatic or non-aromatic heterocyclic compound And more preferably a 5- or 6-membered aromatic heterocyclic group having 3 to 30 carbon atoms (for example, 2-furyl group, 2-thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group), A cyano group, a hydroxyl group, a nitro group, a carboxyl group, an alkoxy group (preferably a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms such as a methoxy group, Toxyl group, isopropoxy group, tert-butoxy group, n-octyloxy group, 2-methoxyethoxy group), aryloxy group (preferably a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, such as phenoxy Group, 2-methylphenoxy group, 4-tert-butylphenoxy group, 3-nitrophenoxy group, 2-tetradecanoylaminophenoxy group), silyloxy group (preferably silyloxy group having 3 to 20 carbon atoms, such as trimethylsilyl group) Oxy group, tert-butyldimethylsilyloxy group), heterocyclic oxy group (preferably a substituted or unsubstituted heterocyclic oxy group having 2 to 30 carbon atoms, 1-phenyltetrazol-5-oxy group, 2-tetrahydropyrani Ruoxy group), acyloxy group (preferably formyloxy group, charcoal) A substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms, such as formyloxy group, acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy Group, p-methoxyphenylcarbonyloxy group), carbamoyloxy group (preferably a substituted or unsubstituted carbamoyloxy group having 1 to 30 carbon atoms, such as N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyl group) Oxy group, morpholinocarbonyloxy group, N, N-di-n-octylaminocarbonyloxy group, Nn-octylcarbamoyloxy group), alkoxycarbonyloxy group (preferably substituted or unsubstituted having 2 to 30 carbon atoms) Alkoxycarbonyloxy group For example, a methoxycarbonyloxy group, an ethoxycarbonyloxy group, a tert-butoxycarbonyloxy group, an n-octylcarbonyloxy group), an aryloxycarbonyloxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy having 7 to 30 carbon atoms) Group, for example, phenoxycarbonyloxy group, p-methoxyphenoxycarbonyloxy group, pn-hexadecyloxyphenoxycarbonyloxy group), amino group (preferably amino group, substituted or unsubstituted having 1 to 30 carbon atoms) An alkylamino group, a substituted or unsubstituted anilino group having 6 to 30 carbon atoms, such as an amino group, a methylamino group, a dimethylamino group, an anilino group, an N-methyl-anilino group, a diphenylamino group), an acylamino group (preferably Is formylami Group, substituted or unsubstituted alkylcarbonylamino group having 1 to 30 carbon atoms, substituted or unsubstituted arylcarbonylamino group having 6 to 30 carbon atoms, such as formylamino group, acetylamino group, pivaloylamino group, lauroylamino Group, benzoylamino group), aminocarbonylamino group (preferably a substituted or unsubstituted aminocarbonylamino group having 1 to 30 carbon atoms, such as carbamoylamino group, N, N-dimethylaminocarbonylamino group, N, N -Diethylaminocarbonylamino group, morpholinocarbonylamino group), alkoxycarbonylamino group (preferably a substituted or unsubstituted alkoxycarbonylamino group having 2 to 30 carbon atoms, such as methoxycarbonylamino group, ethoxycarbonylamino group, tert-butoxyca Bonylamino group, n-octadecyloxycarbonylamino group, N-methyl-methoxycarbonylamino group), aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms, such as phenoxy A carbonylamino group, a p-chlorophenoxycarbonylamino group, an mn-octyloxyphenoxycarbonylamino group), a sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms, For example, sulfamoylamino group, N, N-dimethylaminosulfonylamino group, Nn-octylaminosulfonylamino group), alkyl and arylsulfonylamino groups (preferably substituted or unsubstituted alkyl having 1 to 30 carbon atoms) Sulfonylami A substituted or unsubstituted arylsulfonylamino group having 6 to 30 carbon atoms, such as methylsulfonylamino group, butylsulfonylamino group, phenylsulfonylamino group, 2,3,5-trichlorophenylsulfonylamino group, p-methylphenyl A sulfonylamino group), a mercapto group, an alkylthio group (preferably a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, such as a methylthio group, an ethylthio group, an n-hexadecylthio group), an arylthio group (preferably having a carbon number of 6 to 30 substituted or unsubstituted arylthio groups such as phenylthio group, p-chlorophenylthio group, m-methoxyphenylthio group), heterocyclic thio group (preferably substituted or unsubstituted heterocyclic thio having 2 to 30 carbon atoms) A group such as a 2-benzothiazolylthio group, 1 Phenyltetrazol-5-ylthio group), a sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms, such as an N-ethylsulfamoyl group, an N- (3-dodecyloxypropyl) sulfamoyl group, N, N-dimethylsulfamoyl group, N-acetylsulfamoyl group, N-benzoylsulfamoyl group, N- (N′phenylcarbamoyl) sulfamoyl group), sulfo group, alkyl and arylsulfinyl group (preferably A substituted or unsubstituted alkylsulfinyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsulfinyl group having 6 to 30 carbon atoms such as a methylsulfinyl group, an ethylsulfinyl group, a phenylsulfinyl group, and a p-methylphenylsulfinyl group). Alkyl and aryl sulfo (Preferably a substituted or unsubstituted alkylsulfonyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsulfonyl group having 6 to 30 carbon atoms such as a methylsulfonyl group, an ethylsulfonyl group, a phenylsulfonyl group, p- Methylphenylsulfonyl group), acyl group (preferably formyl group, substituted or unsubstituted alkylcarbonyl group having 2 to 30 carbon atoms, substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, such as acetyl group, A valoylbenzoyl group), an aryloxycarbonyl group (preferably a substituted or unsubstituted aryloxycarbonyl group having 7 to 30 carbon atoms, such as a phenoxycarbonyl group, an o-chlorophenoxycarbonyl group, an m-nitrophenoxycarbonyl group, p-tert-butylphenoxycarbonyl group), An alkoxycarbonyl group (preferably a substituted or unsubstituted alkoxycarbonyl group having 2 to 30 carbon atoms such as methoxycarbonyl group, ethoxycarbonyl group, tert-butoxycarbonyl group, n-octadecyloxycarbonyl group), carbamoyl group (preferably A substituted or unsubstituted carbamoyl group having 1 to 30 carbon atoms such as carbamoyl group, N-methylcarbamoyl group, N, N-dimethylcarbamoyl group, N, N-di-n-octylcarbamoyl group, N- (methyl Sulfonyl) carbamoyl group), aryl and heterocyclic azo groups (preferably substituted or unsubstituted arylazo groups having 6 to 30 carbon atoms, substituted or unsubstituted heterocyclic azo groups having 3 to 30 carbon atoms, for example, phenylazo groups, p-chlorophenylazo group, 5-ethylthio-1, , 4-thiadiazol-2-ylazo group), imide group (preferably N-succinimide group, N-phthalimide group), phosphino group (preferably substituted or unsubstituted phosphino group having 2 to 30 carbon atoms, for example, Dimethylphosphino group, diphenylphosphino group, methylphenoxyphosphino group), phosphinyl group (preferably a substituted or unsubstituted phosphinyl group having 2 to 30 carbon atoms, such as phosphinyl group, dioctyloxyphosphinyl group, di Ethoxyphosphinyl group), phosphinyloxy group (preferably a substituted or unsubstituted phosphinyloxy group having 2 to 30 carbon atoms, such as diphenoxyphosphinyloxy group, dioctyloxyphosphinyloxy group ), A phosphinylamino group (preferably substituted or unsubstituted having 2 to 30 carbon atoms) A phosphinylamino group such as a dimethoxyphosphinylamino group or a dimethylaminophosphinylamino group, a silyl group (preferably a substituted or unsubstituted silyl group having 3 to 30 carbon atoms such as a trimethylsilyl group, tert-butyldimethylsilyl group, phenyldimethylsilyl group).

  Among the above substituents, those having a hydrogen atom may be substituted with the above groups after removing this. Examples of such functional groups include an alkylcarbonylaminosulfonyl group, an arylcarbonylaminosulfonyl group, an alkylsulfonylaminocarbonyl group, and an arylsulfonylaminocarbonyl group. Examples thereof include a methylsulfonylaminocarbonyl group, a p-methylphenylsulfonylaminocarbonyl group, an acetylaminosulfonyl group, and a benzoylaminosulfonyl group.

R ¹ and R ² are preferably chlorine atom, alkyl group, alkenyl group, aryl group, heterocyclic group, hydroxyl group, carboxyl group, alkoxy group, aryloxy group, acyloxy group, amino group, respectively. Preferably, they are a chlorine atom, an alkyl group, an aryl group, a hydroxyl group, and an amino group.

In general formula (5), R ³ and R ⁴ each represent a substituent. Examples of the substituent include the examples given for R ¹ and R ² .
R ³ is preferably a halogen atom, an alkyl group, a cyano group, a hydroxyl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkoxycarbonyloxy group, an amino group, or an acylamino group, more preferably a halogen atom or an alkyl group. , A cyano group, a hydroxyl group, an alkoxy group, an acyloxy group, and an alkoxycarbonyloxy group.
R ⁴ is preferably a halogen atom, alkyl group, alkenyl group, alkynyl group, cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryl Oxycarbonyloxy group, amino group, acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, sulfamoyl group, and Preferably, they are a halogen atom, an alkyl group, a cyano group, a hydroxyl group, an alkoxy group, an acyloxy group, and an alkoxycarbonyloxy group.

In the general formula (5), n represents an integer of 0 to 4, and when n is 2 or more, a plurality of R ³ may be the same or different, and if possible, bonded to each other to form a ring It may be formed. n is preferably an integer of 0 to 2, more preferably 0.

In general formula (5), m represents an integer of 0 to 4. When m is 2 or more, a plurality of R ⁴ may be the same or different from each other, and if possible, they may be bonded to each other to form a ring. m is preferably an integer of 0 to 3.

In General Formula (5), X ¹ represents an integer of ¹ to 5. When X ¹ is 2 or more, a plurality of (R ⁴ ) _m may be the same or different. X ¹ is preferably an integer of 1 to 3, more preferably 1 or 2.

In general formula (5), ^R41 represents a hydrogen atom or a substituent. Examples of the substituent include the examples given for R ¹ and R ² . Preferably, they are a halogen atom, an alkyl group, a cyano group, a hydroxyl group, an alkoxy group, an aryl group, an alkoxycarbonyl group, an acyloxy group, or an alkoxycarbonyloxy group.

The general formula (5) is preferably a compound represented by the general formula (5-2).
General formula (5-2)

In General Formula (5-2), L ³ represents a single bond or a divalent linking group. Examples of L ³ include the examples given for L ¹ and L ² , and the preferred ranges are also the same.

In general formula (5-2), R ⁵ represents a hydrogen atom or a substituent. Examples of R ⁵ include the examples given for R ¹ and R ² , and the preferred ranges are also the same.

In General Formula (5-2), R ⁶ and R ⁷ each represent a substituent. Examples of R ⁶ and R ⁷ include those mentioned for R ⁴ , and preferred ranges are also the same.

In general formula (5-2), j and k each represent an integer of 0 to 4. j and k are each preferably an integer of 0 to 3. When j is 2 or more, a plurality of R ⁷ may be the same or different from each other, and if possible, they may be bonded to each other to form a ring. When k is 2 or more, a plurality of R ⁶ may be the same or different from each other, and if possible, they may be bonded to each other to form a ring.

In General Formula (5-2), X ² represents an integer of 1 to 5. When X ² is 2 or more, a plurality of (R ⁷ ) _j may be the same or different. X ² is preferably an integer of 1 to 3, more preferably 1 or 2.

In the general formula (5-2), R ⁷¹ represents a hydrogen atom or a substituent. Examples of R ⁷¹ are include the examples listed in R ^41, and preferred ranges are also the same.

In General Formula (5-2), X ³ represents an integer of 1 to 5. When X ³ is 2 or more, a plurality of (R ⁶ ) _k may be the same or different. X ³ is preferably an integer of 1 to 3, more preferably 1 or 2.

In general formula (5-2), R ⁶¹ represents a hydrogen atom or a substituent. Examples of R ⁶¹ include those exemplified for R ⁴¹ , and preferred ranges are also the same.

  Hereinafter, the compound represented by the general formula (5) will be described in detail with specific examples, but the present invention is not limited to the following specific examples. Regarding the following compounds, unless otherwise specified, the number in parentheses () indicates the exemplified compound (X).

  Here, Ra, Rb, and Rc are groups represented by the following Table 1, respectively.

  Here, the groups R-1 to R-23 in Table 1 are as follows.

  It is necessary to add at least one of the retardation increasing agents having a large rod-shaped polarizability anisotropy of the molecule to the cellulose in an amount of 0.1 to 30% by mass, preferably 0.5 to 20% by mass. More preferably, it is 1-15 mass%, Most preferably, it is 1-10 mass%. When using 2 or more types, it is preferable that the total amount satisfy | fills said range.

[Retardation increasing agent with large plane polarizability anisotropy of molecules]
Next, a retardation increasing agent having a large plane polarizability anisotropy of the molecule will be described. A compound having a large planar polarizability anisotropy of a molecule can be achieved by linking a highly planar compound such as an aromatic ring in a form in which the conformation between planar molecules is fixed by a hydrogen bond, a conjugated bond, or the like. .

The polarizability of the molecule can be obtained by calculation using the molecular orbital method or the density functional method, and the plane polarizability anisotropy represented by the following formula (2) is 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 6. It must be ^-25 cm ³ or less. When the plane polarizability anisotropy is smaller than the lower limit value, the retardation of the cellulose acylate is preferably reduced. On the other hand, if the plane polarizability anisotropy exceeds the upper limit and is too large, the compatibility with the cellulose acylate is deteriorated, and problems such as the tendency of bleeding out of the retardation increasing agent tend to occur. . The plane polarizability anisotropy is preferably 350 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less.

Formula (2): Δα = (α _x + α _y ) / 2−α _z
(Where α _x is the largest component of the eigenvalues obtained after diagonalizing the polarizability tensor;
α _y is the second largest component of the eigenvalues obtained after diagonalizing the polarizability tensor;
α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor. )

The retardation increasing agent of the present invention having a plane polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the general formula ( The compound represented by 6) is particularly preferred.
General formula (6):

(Wherein R ²¹ , R ²² and R ²³ are each independently an alkyl group, an alkenyl group, an aromatic ring group or a heterocyclic group.)

First, the compound represented by the general formula (6) will be described in detail.
As described above, R ²¹ , R ²² and R ²³ each independently represents an alkyl group, an alkenyl group, an aromatic ring group or a heterocyclic group, and more preferably an aromatic ring or a heterocyclic ring. The aromatic ring represented by each of R ²¹ , R ²² and R ²³ is preferably phenyl or naphthyl. R ²¹ , R ²² and R ²³ may have a substituent on the aromatic ring or heterocyclic ring. Examples of substituents include halogen atoms, hydroxyl groups, cyano groups, nitro groups, carboxyl groups, alkyl groups, alkenyl groups, aryl groups, alkoxy groups, alkenyloxy groups, aryloxy groups, acyloxy groups, alkoxycarbonyl groups, alkenyls. Oxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, alkyl-substituted sulfamoyl group, alkenyl-substituted sulfamoyl group, aryl-substituted sulfamoyl group, sulfonamide group, carbamoyl group, alkyl-substituted carbamoyl group, alkenyl-substituted carbamoyl group, aryl-substituted carbamoyl group, amide Group, alkylthio group, alkenylthio group, arylthio group and acyl group.

When R ²¹ , R ²² and R ²³ represent a heterocyclic group, the heterocyclic ring preferably has aromaticity. The heterocycle having aromaticity is generally an unsaturated heterocycle, preferably a heterocycle having the largest number of double bonds. The heterocyclic ring is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring, and most preferably a 6-membered ring. The hetero atom of the heterocyclic ring is preferably a nitrogen atom, a sulfur atom or an oxygen atom, and particularly preferably a nitrogen atom. As the heterocyclic ring having aromaticity, a pyridine ring (2-pyridyl or 4-pyridyl as the heterocyclic group) is particularly preferable. The heterocyclic group may have a substituent. Examples of the substituent of the heterocyclic group are the same as the examples of the substituent described above. These substituents may be further substituted with the above substituents.

  Preferred examples of the compound represented by the general formula (6) of the present invention are shown below, but the present invention is not limited to these specific examples.

  It is necessary to add at least one of the retardation increasing agents having a large plane polarizability anisotropy of the molecule to the cellulose in an amount of 0.1 to 30% by mass, preferably 0.5 to 20% by mass. More preferably, it is 1-15 mass%, Most preferably, it is 1-10 mass%. When using 2 or more types, it is preferable that the total amount satisfy | fills said range.

  In addition, the retardation increasing agent having a large rod-like polarizability anisotropy of the molecule of the present invention and a retardation increasing agent having a large planar polarizability anisotropy of the molecule can be used to suppress bleed out more effectively. And particularly preferred. When using together, it is preferable that the total amount satisfy | fills the same numerical range as said one type of case. The mixing ratio of these retardation increasing agents is 0.01 to 100 parts by mass of a retardation increasing agent having a large planar polarizability anisotropy with respect to 1 part by mass of the retardation increasing agent having a large rod-like polarizability anisotropy of the molecule. Is preferable, and 0.1-10 mass parts is further more preferable.

[Cellulose acylate]
Next, the cellulose acylate used in the present invention will be described.
The degree of substitution of cellulose acylate means the ratio of acylation of three hydroxyl groups present in the structural unit of cellulose (glucose having a β1 → 4-glycoside bond). The degree of substitution can be calculated by measuring the amount of bound fatty acid per unit weight of cellulose. The measurement method is carried out according to ASTM D817-91.

  The cellulose acylate of the present invention is preferably a cellulose acetate having an acetylation degree of 2.6 or more and 3.0 or less. The degree of acetylation is more preferably from 2.7 to 2.95.

Furthermore, another preferable cellulose acylate of the present invention is a mixed fatty acid ester having an acylation degree of 2 or more and 2.9, an acetyl group and an acyl group having 3 to 4 carbon atoms. The degree of acylation is more preferably from 2.2 to 2.85, and most preferably from 2.5 to 2.8. The degree of acetylation is preferably less than 2.5, more preferably less than 1.9.
Further, the ratio of the acylation degree at the 6-position to the total acylation degree is preferably 0.25 or more, and more preferably 0.3 or more.

  The cellulose acylate used in the present invention preferably has a weight average degree of polymerization of 350 to 800, and more preferably has a weight average degree of polymerization of 370 to 600. The cellulose acylate used in the present invention preferably has a number average molecular weight of 70000 to 230,000, more preferably 75000 to 230,000, and most preferably 78,000 to 120,000. preferable.

  The cellulose acylate used in the present invention can be synthesized using an acid anhydride or acid chloride as an acylating agent. When the acylating agent is an acid anhydride, an organic acid (for example, acetic acid) or methylene chloride is used as a reaction solvent. As the catalyst, a protic catalyst such as sulfuric acid is used. When the acylating agent is an acid chloride, a basic compound is used as a catalyst. In the most general synthetic method in industry, cellulose is an organic acid corresponding to acetyl group and other acyl groups (acetic acid, propionic acid, butyric acid) or acid anhydrides thereof (acetic anhydride, propionic anhydride, butyric anhydride). A cellulose ester is synthesized by esterification with a mixed organic acid component containing.

  In this method, cellulose such as cotton linter and wood pulp is activated with an organic acid such as acetic acid, and then esterified using a mixture of organic acid components as described above in the presence of a sulfuric acid catalyst. There are many cases to do. The organic acid anhydride component is generally used in an excess amount relative to the amount of hydroxyl groups present in the cellulose. In this esterification treatment, in addition to the esterification reaction, a hydrolysis reaction (depolymerization reaction) of the cellulose main chain β1 → 4-glycoside bond) proceeds. When the hydrolysis reaction of the main chain proceeds, the degree of polymerization of the cellulose ester is lowered, and the physical properties of the cellulose ester film to be produced are lowered. Therefore, the reaction conditions such as the reaction temperature are preferably determined in consideration of the degree of polymerization and molecular weight of the resulting cellulose ester.

  In order to obtain a cellulose ester having a high degree of polymerization (high molecular weight), it is important to adjust the maximum temperature in the esterification reaction step to 50 ° C. or lower. The maximum temperature is preferably adjusted to 35 to 50 ° C, more preferably 37 to 47 ° C. A reaction temperature of 35 ° C. or higher is preferable because the esterification reaction proceeds smoothly. A reaction temperature of 50 ° C. or lower is preferable because inconveniences such as a decrease in the degree of polymerization of the cellulose ester do not occur.

  After the esterification reaction, when the reaction is stopped while suppressing the temperature rise, a decrease in the polymerization degree can be further suppressed, and a cellulose ester having a high polymerization degree can be synthesized. That is, when a reaction terminator (for example, water or acetic acid) is added after completion of the reaction, the excess acid anhydride that did not participate in the esterification reaction is hydrolyzed to form a corresponding organic acid as a by-product. This hydrolysis reaction is accompanied by intense heat generation, and the temperature in the reactor rises. If the rate of addition of the reaction terminator is not too high, heat is rapidly generated exceeding the cooling capacity of the reactor, the hydrolysis reaction of the cellulose main chain proceeds significantly, and the degree of polymerization of the resulting cellulose ester decreases. Such a problem does not occur. In addition, a part of the catalyst is bonded to the cellulose during the esterification reaction, and most of the catalyst is dissociated from the cellulose during the addition of the reaction terminator. If the rate of addition of the reaction terminator is not too high at this time, a sufficient reaction time is secured for dissociating the catalyst, and problems such as part of the catalyst remaining in a state of being bound to cellulose are unlikely to occur. Cellulose esters to which a strong acid catalyst is partially bonded are very poor in stability, and are easily decomposed by heat during drying of the product to lower the degree of polymerization. For these reasons, after the esterification reaction, it is preferable to stop the reaction by adding a reaction terminator over a period of preferably 4 minutes or more, more preferably 4 to 30 minutes. In addition, it is preferable if the addition time of the reaction terminator is 30 minutes or less because problems such as a decrease in industrial productivity do not occur.

  As the reaction terminator, water or alcohol that decomposes an acid anhydride is generally used. However, in the present invention, a mixture of water and an organic acid is preferably used as a reaction terminator in order not to precipitate triesters having low solubility in various organic solvents. When the esterification reaction is carried out under the above conditions, a high molecular weight cellulose ester having a weight average polymerization degree of 500 or more can be easily synthesized.

[Ultraviolet absorber]
The cellulose acylate film of the present invention may contain an ultraviolet (UV) absorber in addition to the retardation increasing agent.

  Examples of ultraviolet absorbers include oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, and the like, but less benzotriazole compounds Compounds are preferred. Further, ultraviolet absorbers described in JP-A-10-182621 and JP-A-8-337574, and polymer ultraviolet absorbers described in JP-A-6-148430 are also preferably used. When the cellulose acylate film of the present invention is used as a protective film for a polarizing plate, the ultraviolet absorber is excellent in the ability to absorb ultraviolet rays having a wavelength of 370 nm or less, from the viewpoint of preventing deterioration of a polarizer and liquid crystal, and From the viewpoint of liquid crystal display properties, those that absorb less visible light having a wavelength of 400 nm or more are preferred.

  Specific examples of the benzotriazole ultraviolet absorber useful in the present invention include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t -Butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butyl Phenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl) benzotriazole, 2,2 -Methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- (2'-hydroxy-3'-t-butyl-5) '-Methylph Nyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -6- (linear and side chain dodecyl) -4-methylphenol, octyl-3- [3-t-butyl-4 -Hydroxy-5- (chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazole- Examples include, but are not limited to, mixtures of 2-yl) phenyl] propionate.

  As commercial products, “TINUVIN 109”, “TINUVIN 171”, “TINUVIN 326”, “TINUVIN 328” {all manufactured by Ciba Specialty Chemicals Co., Ltd.} Can be preferably used.

  It is preferable that the addition amount of a ultraviolet absorber is 0.1 mass%-10 mass% with respect to a cellulose acylate.

[Manufacture of cellulose acylate film]
The cellulose acylate film of the present invention can be produced by a solvent cast method. In the solvent cast method, a film is produced using a solution (dope) in which cellulose acylate is dissolved in an organic solvent.

The organic solvent is a solvent selected from ethers having 3 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, esters having 3 to 12 carbon atoms, and halogenated hydrocarbons having 1 to 6 carbon atoms. It is preferable to contain.
Ethers, ketones and esters may have a cyclic structure. A compound having two or more functional groups of ether, ketone, and ester (that is, —O—, —CO—, and —COO—) can also be used as the organic solvent. The organic solvent may have another functional group such as an alcoholic hydroxyl group. In the case of an organic solvent having two or more types of functional groups, the number of carbon atoms is preferably within the above-described preferable number of carbon atoms range of the solvent having any functional group.

Examples of the ether having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole.
Examples of ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclohexanone and methylcyclohexanone.
Examples of the esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.

The number of carbon atoms of the halogenated hydrocarbon is preferably 1 or 2, and most preferably 1. The halogen of the halogenated hydrocarbon is preferably chlorine. The proportion of halogen atoms substituted by halogen in the halogenated hydrocarbon is preferably 25 to 75 mol%, more preferably 30 to 70 mol%, and more preferably 35 to 65 mol%. More preferably, it is most preferable that it is 40-60 mol%. Methylene chloride is a representative halogenated hydrocarbon.
Two or more organic solvents may be mixed and used.

  The cellulose acylate solution can be prepared by a general method comprising processing at a temperature of 0 ° C. or higher (ordinary temperature or high temperature). The solution can be prepared by using a dope preparation method and apparatus in a normal solvent cast method. In the case of a general method, it is preferable to use a halogenated hydrocarbon (particularly methylene chloride) as the organic solvent.

  The amount of cellulose acylate is adjusted so as to be contained in the obtained solution in an amount of 10 to 40% by mass. The amount of cellulose acylate is more preferably 10 to 30% by mass. Arbitrary additives described later may be added to the organic solvent (main solvent).

  The solution can be prepared by stirring cellulose acylate and an organic solvent at room temperature (0 to 40 ° C.). High concentration solutions may be stirred under pressure and heating conditions. Specifically, cellulose acylate and an organic solvent are placed in a pressure vessel and sealed, and stirred while heating to a temperature not lower than the boiling point of the solvent at normal temperature and in a range where the solvent does not boil. The heating temperature is usually 40 ° C. or higher, preferably 60 to 200 ° C., and more preferably 80 to 110 ° C.

  Each component may be coarsely mixed in advance and then placed in a container. Moreover, you may put into a container sequentially. The container must be configured to allow stirring. The container can be pressurized by injecting an inert gas such as nitrogen gas. Moreover, you may utilize the raise of the vapor pressure of the solvent by heating. Or after sealing a container, you may add each component under pressure.

  When heating, it is preferable to heat from the outside of the container. For example, a jacket type heating device can be used. The entire container can also be heated by providing a plate heater outside the container and piping to circulate the liquid.

  Stirring is preferably performed using a stirring blade provided inside the container. The stirring blade preferably has a length that reaches the vicinity of the wall of the container. A scraping blade is preferably provided at the end of the stirring blade in order to renew the liquid film on the vessel wall.

  Instruments such as a pressure gauge and a thermometer may be installed in the container. Each component is dissolved in a solvent in a container. The prepared dope is taken out of the container after cooling, or taken out and then cooled using a heat exchanger or the like.

  A solution can also be prepared by a cooling dissolution method. In the cooling dissolution method, cellulose acylate can be dissolved in an organic solvent that is difficult to dissolve by a normal dissolution method. In addition, even if it is a solvent which can melt | dissolve a cellulose acylate with a normal melt | dissolution method, there exists an effect that a uniform solution can be obtained rapidly according to a cooling melt | dissolution method.

  In the cooling dissolution method, first, cellulose acylate is gradually added to an organic solvent with stirring at room temperature. The amount of cellulose acylate is preferably adjusted so as to be contained in the mixture in an amount of 10 to 40% by mass. The amount of cellulose acylate is more preferably 10 to 30% by mass. Furthermore, you may add the arbitrary additive mentioned later in a mixture.

  The mixture is then cooled to -100 to -10 ° C (preferably -80 to -10 ° C, more preferably -50 to -20 ° C, most preferably -50 to -30 ° C). The cooling can be performed, for example, in a dry ice / methanol bath (−75 ° C.) or a cooled diethylene glycol solution (−30 to −20 ° C.). The mixture of the cellulose acylate and the organic solvent is solidified by cooling.

  The cooling rate is preferably 4 ° C./min or more, more preferably 8 ° C./min or more, and most preferably 12 ° C./min or more. The faster the cooling rate, the better. However, 10,000 ° C./second is the theoretical upper limit, 1000 ° C./second is the technical upper limit, and 100 ° C./second is the practical upper limit. The cooling rate is a value obtained by dividing the difference between the temperature at the start of cooling and the final cooling temperature by the time from the start of cooling to the final cooling temperature.

  Furthermore, when this is heated to 0 to 200 ° C. (preferably 0 to 150 ° C., more preferably 0 to 120 ° C., most preferably 0 to 50 ° C.), cellulose acylate dissolves in the organic solvent. The temperature may be increased by simply leaving it at room temperature or in a warm bath. The heating rate is preferably 4 ° C./min or more, more preferably 8 ° C./min or more, and most preferably 12 ° C./min or more. The higher the heating rate, the better. However, 10,000 ° C./second is the theoretical upper limit, 1000 ° C./second is the technical upper limit, and 100 ° C./second is the practical upper limit. The heating rate is a value obtained by dividing the difference between the temperature at the start of heating and the final heating temperature by the time from the start of heating until the final heating temperature is reached. .

  A uniform solution is obtained as described above. If the dissolution is insufficient, the cooling and heating operations may be repeated. Whether or not the dissolution is sufficient can be determined by merely observing the appearance of the solution with the naked eye.

  In the cooling dissolution method, it is desirable to use a sealed container in order to avoid moisture mixing due to condensation during cooling. In the cooling and heating operation, when the pressure is applied during cooling and the pressure is reduced during heating, the dissolution time can be shortened. In order to perform pressurization and decompression, it is desirable to use a pressure-resistant container.

In addition, according to the measurement by a differential scanning calorimeter (DSC), the 20 mass% solution which melt | dissolved cellulose acetate (acetylation degree: 60.9%, viscosity average polymerization degree: 299) in methyl acetate by the cooling dissolution method is. In the vicinity of 33 ° C., there exists a quasi-phase transition point between a sol state and a gel state, and a uniform gel state is obtained below this temperature. Accordingly, this solution is preferably kept at a temperature equal to or higher than the pseudo phase transition temperature, preferably about 10 ° C. plus the gel phase transition temperature. However, this pseudo phase transition temperature varies depending on the degree of acetylation of cellulose acetate, the degree of viscosity average polymerization, the concentration of the solution, and the organic solvent used.

  A cellulose acylate film is produced from the prepared cellulose acylate solution (dope) by a solvent cast method. It is preferable to add a retardation increasing agent to the dope. The dope is cast on a drum or band and the solvent is evaporated to form a film. The concentration of the dope before casting is preferably adjusted so that the solid content is 18 to 35%. The surface of the drum or band is preferably finished in a mirror state. The dope is preferably cast on a drum or band having a surface temperature of 10 ° C. or less.

  Regarding the drying method in the solvent casting method, U.S. Pat. No. 736892 and JP-B Nos. 45-4554, 49-5614, JP-A-60-176834, JP-A-60-203430, and JP-A-62-115035. Drying on the band or drum can be performed by blowing air or an inert gas such as nitrogen.

  The obtained film can be peeled off from the drum or band and further dried by high-temperature air whose temperature is successively changed from 100 ° C. to 160 ° C. to evaporate the residual solvent. The above method is described in Japanese Patent Publication No. 5-17844. According to this method, it is possible to shorten the time from casting to stripping. In order to carry out this method, it is necessary for the dope to gel at the surface temperature of the drum or band during casting.

  Using the prepared cellulose acylate solution (dope), two or more layers can be cast to form a film. In this case, it is preferable to produce a cellulose acylate film by a solvent cast method. The dope is cast on a drum or band and the solvent is evaporated to form a film. It is preferable to adjust the concentration of the dope before casting so that the solid content is in the range of 10 to 40% by mass. The surface of the drum or band is preferably finished in a mirror state.

  When casting a plurality of cellulose acylate solutions of two or more layers, it is possible to cast a plurality of cellulose acylate solutions, from a plurality of casting openings provided at intervals in the direction of travel of the support. You may produce a film, casting and laminating the solution containing a cellulose acylate, respectively. For example, the methods described in JP-A-61-158414, JP-A-1-122419, and JP-A-11-198285 can be used. Also, a film can be formed by casting a cellulose acylate solution from two casting ports. For example, JP-B-60-27562, JP-A-61-94724, JP-A-61-947245, JP-A-61-104413, JP-A-61-158413, and JP-A-6-134933. The method described in each publication can be used. Further, a flow of a cellulose acylate film in which a flow of a high-viscosity cellulose acylate solution described in JP-A-56-162617 is wrapped with a low-viscosity cellulose acylate solution and the high-low viscosity cellulose acylate solution is simultaneously extruded. A rolling method can also be used.

  Also, using two casting ports, the film formed on the support by the first casting port is peeled off, and the second casting is performed on the side in contact with the support surface to produce a film. You can also For example, the method described in Japanese Patent Publication No. 44-20235 can be mentioned.

As the cellulose acylate solution to be cast, the same solution may be used, or different cellulose acylate solutions may be used. In order to give a function to a plurality of cellulose acylate layers, a cellulose acylate solution corresponding to the function may be extruded from each casting port. Furthermore, the cellulose acylate solution of the present invention can be cast simultaneously with other functional layers (for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, an ultraviolet absorption layer, a polarizing layer, etc.).

  In the conventional single-layer solution, it is necessary to extrude a cellulose acylate solution having a high concentration and a high viscosity in order to obtain a necessary film thickness. In such a case, the stability of the cellulose acylate solution is poor and solid matter is generated, which often causes problems due to defects or poor flatness. As a solution to this problem, by casting a plurality of cellulose acylate solutions from the casting port, it is possible to extrude a highly viscous solution onto the support at the same time, improving the flatness and improving the planar film. Not only can be produced, but also the use of a concentrated cellulose acylate solution can reduce the drying load and increase the production speed of the film.

  Degradation inhibitors (for example, antioxidants, peroxide decomposers, radical inhibitors, metal deactivators, acid scavengers, amines, etc.) may be added to the cellulose acylate film. The deterioration preventing agents are described in JP-A-3-199201, JP-A-51907073, JP-A-5-194789, JP-A-5-271471, and JP-A-6-107854. The addition amount of the deterioration preventing agent is preferably 0.01 to 1% by mass of the solution (dope) to be prepared, and more preferably 0.01 to 0.2% by mass. If the addition amount is 0.01% by mass or more, the effect of the deterioration inhibitor is sufficiently exhibited, and if the addition amount is 1% by mass or less, the deterioration inhibitor bleeds out to the film surface (bleeding). And the like are less likely to occur. Examples of particularly preferred deterioration inhibitors include butylated hydroxytoluene (BHT) and tribenzylamine (TBA).

  These steps from casting to post-drying may be performed in an air atmosphere or an inert gas atmosphere such as nitrogen gas. The winder used in the production of the cellulose acylate film of the present invention may be a commonly used winding machine such as a constant tension method, a constant torque method, a taper tension method, or a program tension control method with a constant internal stress. It can be wound up by a take-up method.

[Characteristics of cellulose acylate film]
[Thickness of cellulose acylate film]
The thickness of the cellulose acylate film of the present invention is preferably 10 μm to 200 μm, more preferably 20 μm to 150 μm, and most preferably 30 μm to 100 μm.

[Moisture content of cellulose acylate film]
The moisture content of the cellulose acylate film can be evaluated by measuring the equilibrium moisture content at a constant temperature and humidity. Equilibrium moisture content was calculated by measuring the moisture content of the sample that reached equilibrium after being left at a constant temperature and humidity for 24 hours, and dividing the moisture content (g) by the sample mass (g). It is.
The water content of the cellulose acylate film of the present invention at 25 ° C. and 80% RH is preferably 5.0% by mass or less, more preferably 4.3% by mass or less, and 3.8% by mass or less. Most preferably it is.

[Moisture permeability]
The water vapor transmission rate is calculated as the amount of water (g) that evaporates in 24 hours per 1 m ^{2 of} area by measuring the water vapor transmission rate of each sample according to the method described in JIS Z-0208. The moisture permeability is a film property closely related to the durability of the polarizing plate, and the durability of the polarizing plate can be improved by reducing the moisture permeability. The cellulose acylate film of the present invention, 60 ° C., it is preferable moisture permeability 95% RH, 24 hours is 200 g / m ² or more 1700 g / m ² or less. More preferably, the 500 g / m ² or more 1400 g / m ² or less.

[Saponification]
The cellulose acylate film of the present invention can be used as a polarizing plate protective film by imparting adhesiveness to polyvinyl alcohol by alkali saponification treatment.

  The alkali saponification treatment of the cellulose acylate film is preferably carried out in a cycle in which the film surface is immersed in an alkaline solution, neutralized with an acidic solution, washed with water and dried. Examples of the alkaline solution include potassium hydroxide solution and sodium hydroxide solution, and the concentration of hydroxide ions is preferably in the range of 0.1 to 5.0 mol / L, and preferably 0.5 to 4.0 mol / L. More preferably, it is in the range. The alkaline solution temperature is preferably in the range of room temperature to 90 ° C, more preferably in the range of 40 to 70 ° C.

[Stretching treatment]
For the polarizing plate protective film of the present invention, a stretched cellulose acylate film can also be preferably used. A desired retardation can be imparted to the cellulose acylate film by the stretching treatment, and the cellulose acylate film can also have a function as a retardation film. The stretching direction of the cellulose acylate film is preferably either the width direction or the longitudinal direction.

  Methods for stretching in the width direction are described in, for example, JP-A-62-115035, JP-A-4-152125, JP-A-2842211, JP-A-298310, and JP-A-11-48271. Yes.

  The film is stretched at room temperature or under heating conditions. The heating temperature is preferably not higher than the glass transition temperature of the film. The film can be stretched by a treatment during drying, and is particularly effective when the solvent remains. In the case of stretching in the longitudinal direction, for example, the film is stretched by adjusting the speed of the film transport roller so that the film winding speed is higher than the film peeling speed. In the case of stretching in the width direction, the film can also be stretched by conveying while holding the width of the film with a tenter and gradually widening the width of the tenter. After the film is dried, it can be stretched using a stretching machine (preferably uniaxial stretching using a long stretching machine).

  The stretch ratio of the film (elongation with respect to the film before stretching) is preferably 3% to 200%, more preferably 5% to 150%. The stretching speed is preferably 1% / min to 100% / min, more preferably 5% / min to 80% / min, and most preferably 10% / min to 60% / min.

  Moreover, it is preferable that the cellulose acylate film of the present invention is produced through a step (hereinafter referred to as a relaxation step) in which the cellulose acylate film of the present invention is stretched up to the maximum draw ratio and then held at a draw ratio lower than the maximum draw ratio for a certain time. The stretching ratio in the relaxation step is preferably from 50% to 99% of the maximum stretching ratio, more preferably from 70% to 97%, and most preferably from 90% to 95%. Moreover, the time of the relaxation process is preferably 1 second or more and 120 seconds or less, and more preferably 5 seconds or more and 100 seconds or less.

By setting the stretching ratio and time in the relaxation step within the above ranges, the degree of orientation of the retardation increasing agent is increased, and a cellulose acylate film with high retardation and small in-plane retardation fluctuation can be obtained. Since the retardation increasing agent of the present invention has a long intermolecular distance and requires time for the alignment state to settle to an equilibrium state, the method of controlling the alignment state by the stretching speed and relaxation process is particularly effective.

[Film retardation]
In this specification, Re _λ and Rth _λ represent in-plane retardation and retardation in the thickness direction at the wavelength λ, respectively. Re _λ is measured by making light having a wavelength of λ nm incident in the normal direction of the film in “KOBRA 21ADH” (manufactured by Oji Scientific Instruments). Rth _λ is light having a wavelength of λ nm from the direction inclined by + 40 ° with respect to the film normal direction, with Re _λ and the in-plane slow axis (determined by “KOBRA 21ADH”) as the tilt axis (rotation axis). And a retardation value measured by making light of wavelength λ nm incident from a direction inclined by −40 ° with respect to the normal direction of the film with the in-plane slow axis as the tilt axis (rotation axis). “KOBRA 21ADH” is calculated based on the retardation values measured in a total of three directions.

Here, the assumed value of average refractive index is “Polymer Handbook” (John Wiley &
SONS, Inc. ), And catalog values of various optical films can be used. If the average refractive index is not known, it can be measured with an Abbe refractometer.

Examples of the average refractive index values of main optical films are given below:
Cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59). By inputting the assumed average refractive index values and thicknesses, (refractive index of the film forming direction) n _x by KOBRA 21ADH, n _y (refractive index in the width direction), n _z (refractive index in the thickness direction) calculate.

The Re ₅₉₀ of the cellulose acylate film of the present invention is preferably 20 to 200 nm, more preferably 30 to 150 nm, and most preferably 60 to 120 nm. Rth ₅₉₀ is preferably 50 to 400 nm, more preferably 70 to 400 nm, still more preferably 100 to 300 nm, and most preferably 150 to 250 nm.
The Rth ₅₉₀ / Re ₅₉₀ ratio is preferably 1 or more and 10 or less, and more preferably 2 or more and 8 or less.

  In the OCB mode and the TN mode, an optically anisotropic layer can be applied on the cellulose acylate film having the retardation value, and used as an optical compensation film.

[Photoelasticity of cellulose acylate]
The photoelastic coefficient of the cellulose acylate of the present invention is preferably 60 × 10 ⁻⁸ cm ² / N or less, and more preferably 20 × 10 ⁻⁸ cm ² . The photoelastic coefficient can be obtained by an ellipsometer.

[Glass transition temperature of cellulose acylate]
The glass transition temperature of the cellulose acylate of the present invention is preferably 120 ° C. or higher, and more preferably 140 ° C. or higher. The glass transition temperature is a temperature at which the base line derived from the glass transition of the film starts to change and a temperature at which it returns to the base line again when measured at a heating rate of 10 ° C./min using a differential scanning calorimeter (DSC). Is obtained as an average value of.

<Polarizing plate>
[Configuration of polarizing plate]
First, the protective film and polarizer which comprise the polarizing plate of this invention are demonstrated.
The polarizing plate of this invention may have an adhesive layer, a separate film, and a protective film as a component other than a polarizer and a protective film.

(1) Protective film The polarizing plate of the present invention has a total of two protective films, one on each side of the polarizer, at least one of which is the cellulose acylate film of the present invention. Moreover, it is preferable that at least one of the two protective films has a function as a retardation film. When using the polarizing plate of this invention for a liquid crystal display device, it is preferable that at least one of the two polarizing plates arrange | positioned at the both sides of a liquid crystal cell is a polarizing plate of this invention.

  The protective film on the side different from the cellulose acylate film of the present invention used in the present invention is manufactured from norbornene resin, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, polyarylate, polysulfone, cellulose acylate and the like. A polymer film is preferred.

(2) Polarizer The polarizer used in the present invention is preferably composed of polyvinyl alcohol (PVA) and a dichroic molecule, but as described in JP-A-11-248937, A polyvinylene polarizer in which a polyene structure is produced by dehydrating and dechlorinating vinyl chloride and then oriented can also be used.

  PVA is a polymer material obtained by saponifying polyvinyl acetate, but may contain components copolymerizable with vinyl acetate such as unsaturated carboxylic acids, unsaturated sulfonic acids, olefins, and vinyl ethers. In addition, modified PVA containing an acetoacetyl group, a sulfonic acid group, a carboxyl group, an oxyalkylene group, or the like can also be used.

  The saponification degree of PVA is not particularly limited, but is preferably 80 to 100 mol%, particularly preferably 90 to 100 mol% from the viewpoint of solubility and the like. The degree of polymerization of PVA is not particularly limited, but is preferably 1000 to 10,000, and particularly preferably 1500 to 5000.

  The syndiotacticity of PVA is preferably 55% or more for improving durability as described in Japanese Patent No. 2978219, but 45 to 52.5% described in Japanese Patent No. 3317494. Can also be preferably used.

  After PVA is formed into a film, it is preferable to introduce a dichroic molecule to constitute a polarizer. As a method for producing a PVA film, a method of forming a film by casting a stock solution in which a PVA resin is dissolved in water or an organic solvent is generally preferably used. The concentration of the polyvinyl alcohol-based resin in the stock solution is usually 5 to 20% by mass, and a PVA film having a thickness of 10 to 200 μm can be produced by forming this stock solution by casting. The PVA film can be produced with reference to Japanese Patent No. 3342516, Japanese Patent Application Laid-Open Nos. 09-328593, 2001-302817, and 2002-144401.

The crystallinity of the PVA film is not particularly limited. However, the average crystallinity (X _c ) described in the specification of Japanese Patent No. 3251073 is 50 to 75% by mass and in-plane hue variation is reduced. A PVA film having a crystallinity of 38% or less described in Japanese Unexamined Patent Publication No. 2002-236214 can be used.

The birefringence (Δn) of the PVA film is preferably small, and a PVA film having a birefringence of 1.0 × 10 ⁻³ or less described in Japanese Patent No. 3342516 can be preferably used. However, as described in JP-A-2002-228835, PV
In order to obtain a high degree of polarization while avoiding cutting during stretching of the A film, the birefringence of the PVA film may be 0.02 or more and 0.01 or less, as described in JP-A-2002-060505. to _{(n x + n y) /} 2-n _z values may be used as 0.0003 or 0.01 or less. The retardation (in-plane) of the PVA film is preferably from 0 nm to 100 nm, and more preferably from 0 nm to 50 nm. Moreover, 0 nm or more and 500 nm or less are preferable, and, as for Rth (film thickness direction) of a PVA film, 0 nm or more and 300 nm or less are more preferable.

In addition, the polarizing plate of the present invention includes a PVA film having a 1,2-glycol bond amount of 1.5 mol% or less described in Japanese Patent No. 3021494; PVA film having 500 or less optical foreign matters of 5 μm or more per 100 cm ² ; hot water cutting temperature spot in the TD direction of the film described in JP-A No. 2002-030163 is 1.5 ° C. or less A PVA film which is 1 to 100 parts by mass of a trivalent or hexavalent polyalcohol such as glycerin or a mixture of 15% by mass or more of a plasticizer described in JP-A-06-289225 The PVA film formed from can be preferably used.

  Although the film thickness before extending | stretching of a PVA film is not specifically limited, From a viewpoint of stability of film holding | maintenance and the uniformity of extending | stretching, 1 micrometer-1 mm are preferable, and 20-200 micrometers is especially preferable. As described in JP-A-2002-236212, a thin PVA film may be used in which the stress generated when stretching 4 to 6 times in water is 10 N or less.

As the dichroic molecule, a higher-order iodine ion such as I ₃ ⁻ or I ₅ ⁻ or a dichroic dye can be preferably used. In the present invention, higher-order iodine ions are particularly preferably used. Higher-order iodine ions can be found in “Applications of Polarizing Plates” by Nagata Ryo, CMC Publishing, “Industrial Materials” Vol. 28, No. 7, p. 39-p. 45, PVA can be produced by immersing PVA in a solution obtained by dissolving iodine in a potassium iodide aqueous solution and / or a boric acid aqueous solution and adsorbing and orienting the PVA.

  When a dichroic dye is used as the dichroic molecule, an azo dye is preferable, and a bisazo dye and a trisazo dye are particularly preferable. The dichroic dye is preferably a water-soluble dye. For this reason, a hydrophilic substituent such as a sulfonic acid group, an amino group or a hydroxyl group is introduced into the dichroic molecule, so that a free acid, an alkali metal salt, an ammonium salt or an amine is introduced. It is preferably used as a salt.

  Specific examples of such dichroic dyes include C.I. I. Direct Red 37, Congo Red (C.I. Direct Red 28), C.I. I. Direct Violet 12, C.I. I. Direct Blue 90, C.I. I. Direct Blue 22, C.I. I. Direct Blue 1, C.I. I. Direct Blue 151, C.I. I. Benzidines such as Direct Green 1; C.I. I. Direct Yellow 44, C.I. I. Direct Red 23, C.I. I. Diphenylurea series such as Direct Red 79; I. Stilbene series such as Direct Yellow 12; I. Dinaphthylamine type such as Direct Red 31; I. Direct Red 81, C.I. I. Direct Violet 9, C.I. I. Examples thereof include a J acid type such as Direct Blue 78.

In addition, C.I. I. Direct Yellow 8, C.I. I. Direct Yellow 28, C.I. I. Direct Yellow 86, C.I. I. Direct
Yellow 87, C.I. I. Direct Yellow 142, C.I. I. Dir
ect Orange 26, C.I. I. Direct Orange 39, C.I. I. Direct Orange 72, C.I. I. Direct Orange 106, C.I. I. Direct Orange 107, C.I. I. Direct Red 2, C.I. I. Direct Red 39, C.I. I. Direct Red 83, C.I. I. Direct Red 89, C.I. I. Direct Red 240, C.I. I. Direct
Red 242, C.I. I. Direct Red 247, C.I. I. Direct Violet 48, C.I. I. Direct Violet 51, C.I. I. Direct
Violet 98, C.I. I. Direct Blue 15, C.I. I. Direct
Blue 67, C.I. I. Direct Blue 71, C.I. I. Direct Blue 98, C.I. I. Direct Blue 168, C.I. I. Direct Blue 202, C.I. I. Direct Blue 236, C.I. I. Direct Blue 249, C.I. I. Direct Blue 270, C.I. I. Direct Green 59, C.I. I. Direct Green 85, C.I. I. Direct Brown 44, C.I. I. Direct Brown 106, C.I. I. Direct Brown 195, C.I. I. Direct Brown 210, C.I. I. Direct
Brown 223, C.I. I. Direct Brown 224, C.I. I. Direct Black 1, C.I. I. Direct Black 17, C.I. I. Direct Black 19, C.I. I. Direct Black 54 and the like are further disclosed in JP-A-62-70802, JP-A-1-161202, JP-A-1-172906, JP-A-1-172907, JP-A-1-183602, JP-A-1-248105, The dichroic dyes described in JP-A-1-265205 and JP-A-7-261024 can also be preferably used. In order to produce dichroic molecules having various hues, two or more of these dichroic dyes may be blended. When a dichroic dye is used, the adsorption thickness may be 4 μm or more as described in JP-A No. 2002-082222.

  The content of the dichroic molecule relative to the polyvinyl alcohol polymer constituting the matrix of the film is generally adjusted in the range of 0.01% by mass to 5% by mass. If the content of the dichroic molecule is equal to or higher than the lower limit value, a favorable degree of polarization is exhibited, and if the content is equal to or lower than the upper limit value, problems such as a decrease in single plate transmittance do not occur.

A preferable film thickness of the polarizer is preferably 5 μm to 40 μm, and more preferably 10 μm to 30 μm. The ratio of the thickness of the polarizer to the thickness of the protective film described later is 0.01 ≦ D _A (polarizer film thickness) / D _B (protective film thickness) ≦ described in JP-A-2002-174727. A range of 0.16 is also preferable.

  The crossing angle between the slow axis of the protective film and the absorption axis of the polarizer may be any value, but is preferably parallel or an azimuth angle of 45 ± 20 °.

[Polarizing plate manufacturing process]
Next, the manufacturing process of the polarizing plate of this invention is demonstrated.
The production process of the polarizing plate in the present invention is preferably composed of a PVA film swelling process, a dyeing process, a hardening process, a stretching process, a drying process, a protective film bonding process, and a post-bonding drying process. The order of the dyeing step, the hardening step, and the stretching step may be arbitrarily changed, or several steps may be combined and performed simultaneously. Furthermore, as described in Japanese Patent No. 3331615, washing with water after the hardening step can be preferably performed.

  In the present invention, it is particularly preferable that the PVA film swelling step, the dyeing step, the hardening step, the stretching step, the drying step, the protective film bonding step, and the post-bonding drying step are sequentially performed in the order described. Further, an on-line surface inspection process may be provided during or after the above process.

The swelling process of the PVA film is preferably performed only with water, but as described in JP-A-10-153709, stabilization of optical performance and avoiding wrinkle generation of the polarizing plate substrate in the production line Therefore, the degree of swelling of the polarizing plate substrate can be managed by swelling the polarizing plate substrate with an aqueous boric acid solution.
Moreover, although the temperature and time of a swelling process can be defined arbitrarily, 10 to 60 degreeC and 5 to 2000 second are preferable.

  For the dyeing process of the PVA film, the method described in JP-A-2002-86554 can be used. Moreover, as a dyeing | staining method, not only immersion but arbitrary means, such as application | coating or spraying of an iodine or dye solution, are possible. Further, as described in JP-A-2002-290025, a method of dyeing while stirring the iodine concentration, the dyeing bath temperature, the draw ratio in the bath, and the bath liquid in the bath may be used.

  When higher-order iodine ions are used as the dichroic molecule, in order to obtain a high-contrast polarizing plate, it is preferable to use a solution obtained by dissolving iodine in an aqueous potassium iodide solution in the dyeing step. In this case, iodine in the iodine-potassium iodide aqueous solution is 0.05 to 20 g / L, further 0.5 to 2 g / L; potassium iodide is 3 to 200 g / L, and further 30 to 120 g / L; iodine. : The mass ratio of potassium iodide is 1: 1 to 2000, and more preferably 1:30 to 120. The dyeing time is preferably 10 to 1200 seconds, more preferably 30 to 600 seconds, and the liquid temperature is preferably 10 to 60 ° C, more preferably 20 to 50 ° C.

  Further, as described in Japanese Patent No. 3145747, boron compounds such as boric acid and borax may be added to the dyeing solution.

  In the hardening process of the PVA film, it is preferable to immerse the PVA film in a crosslinking agent solution, or apply the crosslinking agent solution to the film to include the crosslinking agent. Further, as described in JP-A-11-52130, the hardening process can be performed in several steps.

  As the crosslinking agent, those described in US Reissue Pat. No. 2,328,977 can be used, and as described in Japanese Patent No. 3357109, in order to improve dimensional stability, a polyvalent aldehyde is used as a crosslinking agent. Although it can be used, boric acids are most preferably used. When boric acid is used as the crosslinking agent used in the hardening step, metal ions may be added to the boric acid-potassium iodide aqueous solution. Zinc chloride is preferable as the metal ion, but as described in JP-A-2000-35512, zinc halide such as zinc iodide, zinc sulfate such as zinc acetate, and zinc acetate are used instead of zinc chloride. It can also be used.

  In the present invention, it is preferable to prepare a boric acid-potassium iodide aqueous solution to which zinc chloride has been added, and perform dura- tion by immersing the PVA film. Boric acid is 1 to 100 g / L, more preferably 10 to 80 g / L; potassium iodide is 1 to 120 g / L, further 5 to 100 g / L; zinc chloride is 0.01 to 10 g / L, and more preferably 0. 02-8 g / L; Hardening time is 10 to 1200 seconds, more preferably 30 to 600 seconds; liquid temperature is preferably 10 to 60 ° C., more preferably 20 to 50 ° C.

The stretching process of the PVA film is preferably a longitudinal uniaxial stretching method as described in US Pat. No. 2,454,515 or a tenter method as described in JP-A-2002-86554. Can be used. A preferable draw ratio is 2 times or more and 12 times or less, and more preferably 3 times or more and 10 times or less. The relationship between the draw ratio, the thickness of the original fabric and the thickness of the polarizer is described in JP-A-2002-040256:
(Polarizer film thickness / raw film thickness after protective film bonding) × (total stretching ratio)> 0.17
Or the relationship between the width of the polarizer when leaving the final bath and the width of the polarizer when bonding the protective film is described in JP-A-2002-040247:
0.80 ≦ (polarizer width at the time of protective film bonding / polarizer width when leaving the final bath) ≦ 0.95
It can also be preferably performed.

  As the PVA film drying step, a method known in JP-A-2002-86554 can be used, but a preferable temperature range is 30 ° C. to 100 ° C., and a preferable drying time is 30 seconds to 60 minutes. In addition, as described in Japanese Patent No. 3148513, heat treatment is performed such that the fading temperature in water is 50 ° C. or more, and it is described in Japanese Patent Laid-Open Nos. 07-325215 and 07-325218. As described above, aging in a temperature and humidity controlled atmosphere can also be preferably employed.

  The protective film laminating step is a step of laminating both surfaces of the above-described polarizer that has gone through the drying step with two protective films. A method of bonding with a pair of rolls is preferably used so that the adhesive liquid is supplied immediately before bonding and the polarizer and the protective film are overlapped. Further, as described in JP-A-2001-296426 and JP-A-2002-86554, in order to suppress the groove-like unevenness of the record due to the stretching of the polarizer, It is preferable to adjust the moisture content. In the present invention, a moisture content of 0.1% by mass to 30% by mass is preferably used.

  The adhesive between the polarizer and the protective film is not particularly limited, and examples thereof include PVA resin (including modified PVA such as acetoacetyl group, sulfonic acid group, carboxyl group, oxyalkylene group) and boron compound aqueous solution, Of these, PVA resins are preferred. The thickness of the adhesive layer is preferably 0.01 to 5 μm, and particularly preferably 0.05 to 3 μm after drying.

  Moreover, in order to improve the adhesive force of a polarizer and a protective film, it is preferable to perform adhesion after surface-treating the protective film to make it hydrophilic. The surface treatment method is not particularly limited, and a known method such as a saponification method using an alkaline solution or a corona treatment method can be used. Further, an easy adhesion layer such as a gelatin subbing layer may be provided after the surface treatment. As described in JP-A-2002-267839, the contact angle of the protective film surface with water is preferably 50 ° or less.

  The drying conditions after bonding are in accordance with the method described in JP-A-2002-86554, but a preferable temperature range is 30 ° C. to 100 ° C., and a preferable drying time is 30 seconds to 60 minutes. It is also preferable to perform aging in an atmosphere with temperature and humidity control as described in JP-A-07-325220.

The element content in the polarizer is as follows: iodine 0.1-3.0 g / m ² , boron 0.1-5.0 g / m ² , potassium 0.1-2.00 g / m ² , zinc 0-2. It is preferably 00 g / m ² . Further, the potassium content may be 0.2% by mass or less as described in JP-A No. 2001-166143, and the zinc content in the polarizer is described in JP-A No. 2000-035512. It is good also as 0.04 mass%-0.5 mass% currently being carried out.

  As described in Japanese Patent No. 3323255, in order to increase the dimensional stability of the polarizing plate, an organic titanium compound and / or an organic zirconium compound are used in any of the dyeing process, the stretching process, and the hardening process. In addition, at least one compound selected from organic titanium compounds and organic zirconium compounds can also be contained. Further, a dichroic dye may be added to adjust the hue of the polarizing plate.

[Characteristics of polarizing plate]
(1) Transmittance and degree of polarization The preferred single plate transmittance of the polarizing plate of the present invention defined by the following formula (3) is 42.5% or more and 49.5% or less, more preferably 42. It is 8% or more and 49.0% or less. A preferable range of the degree of polarization defined by the following mathematical formula (4) is 99.900% or more and 99.999% or less, and more preferably 99.940% or more and 99.995% or less. A preferable range of the parallel transmittance is 36% or more and 42% or less, and a preferable range of the orthogonal transmittance is 0.001% or more and 0.05% or less. The preferable range of the dichroic ratio defined by the following mathematical formula (5) is 48 or more and 1215 or less, and more preferably 53 or more and 525 or less.

The above transmittance is defined by the following mathematical formula (3) based on JIS Z-8701.
Formula (3):

  Here, K, S (λ), y (λ), and τ (λ) are as follows.

S (λ): spectral distribution of standard light used for color display y (λ): color matching function in XYZ color system (CIE1931 color system) τ (λ): spectral transmittance

The degree of polarization of the polarizing plate of the present invention is defined by the following mathematical formula (4).
Formula (4):

Furthermore, the dichroic ratio (Rd) of the polarizing plate of the present invention is defined by the following mathematical formula (5).
Formula (5):

  The iodine concentration and the single plate transmittance may be within the ranges described in JP-A-2002-258051.

  The parallel transmittance may be small in wavelength dependency as described in Japanese Patent Application Laid-Open No. 2001-083328 and Japanese Patent Application Laid-Open No. 2002-022950. The optical characteristics when the polarizing plates are arranged in crossed Nicols may be in the range described in Japanese Patent Application Laid-Open No. 2001-091736, and the relationship between parallel transmittance and orthogonal transmittance is disclosed in Japanese Patent Application Laid-Open No. 2002-174728. It may be within the range described in the publication.

  As described in Japanese Patent Application Laid-Open No. 2002-221618, the standard deviation of parallel transmittance every 10 nm is 3 or less and the light wavelength is 420 to 700 nm when the light wavelength is 420 to 700 nm. The minimum value of (parallel transmittance / orthogonal transmittance) every 10 nm may be 300 or more.

The parallel transmittance and orthogonal transmittance at a wavelength of 440 nm, the parallel transmittance, the parallel transmittance and the orthogonal transmittance at a wavelength of 550 nm, and the parallel transmittance and the orthogonal transmittance at a wavelength of 610 nm of the polarizing plate are disclosed in JP-A-2002-258042. The range described in JP 2002-258043 A can also be preferably performed.

(2) Hue The hue of the polarizing plate of the present invention is preferably determined using the lightness index L ^* and the chromaticness index a ^* and b ^* in the L ^* a ^* b ^* color system recommended as the CIE uniform perceptual space. Be evaluated.
L ^* , a ^* , and b ^* are defined by Equation (6) using X, Y, and Z in the table XYZ color system.
Formula (6):

Here, X ₀ , Y ₀ , and Z ₀ represent tristimulus values of the illumination light source. In the case of standard light C, X ₀ = 98.072, Y ₀ = 100, Z ₀ = 118.225, and standard light D _In the case of ₆₅ , X ₀ = 95.045, Y ₀ = 100, Z ₀ = 108.892.

The preferable range of a ^* for a single polarizing plate is −2.5 or more and 0.2 or less, and more preferably −2.0 or more and 0 or less. A preferable range of b ^* of the single polarizing plate is 1.5 or more and 5 or less, and more preferably 2 or more and 4.5 or less. The preferable range of a ^* of the parallel transmitted light of the two polarizing plates is −4.0 to 0, and more preferably −3.5 to −0.5. The preferred range of b ^* of the parallel transmitted light of the two polarizing plates is 2.0 or more and 8 or less, more preferably 2.5 or more and 7 or less. The preferable range of a ^* of the orthogonally transmitted light of the two polarizing plates is −0.5 or more and 1.0 or less, and more preferably 0 or more and 2 or less. The preferable range of b ^* of the orthogonally transmitted light of the two polarizing plates is −2.0 or more and 2 or less, and more preferably −1.5 or more and 0.5 or less.

The hue may be evaluated by chromaticity coordinates (x, y) calculated from the X, Y, and Z. For example, the chromaticity (x _p , y _p ) of parallel transmitted light of two polarizing plates and The chromaticity (x _c , y _c ) of the orthogonal transmitted light is set to a range described in JP 2002-214436 A, JP 2001-166136 A, and JP 2002-169024 A, or hue and absorbance. It is also preferable to make this relationship within the range described in JP-A-2001-311827.

(3) Viewing angle characteristics When a polarizing plate is placed in crossed Nicols and light with a wavelength of 550 nm is incident, when normal light is incident, the angle from 45 ° to the polarization axis is 40 ° to the normal. It is also preferable that the transmittance ratio and the xy chromaticity difference when incident at an angle are within the ranges described in Japanese Patent Laid-Open Nos. 2001-166135 and 2001-166137. Further, as described in JP-A-10-068817, the light transmittance (T ₀ ) in the vertical direction and the light in the direction inclined by 60 ° from the normal line of the laminated body of the polarizing plate laminated body arranged in crossed Nicols. The ratio (T ₆₀ / T ₀ ) with the transmittance (T ₆₀ ) is set to 10000 or less, or as described in JP-A-2002-139625, the polarizing plate has an arbitrary angle from the normal to an elevation angle of 80 °. When natural light is incident at an angle, the transmittance difference of transmitted light within a wavelength range of 20 nm is set to 6% or less in the wavelength range of 520 to 640 nm of the transmission spectrum, or described in JP-A-08-248201. It is also preferable that the difference in luminance of transmitted light at an arbitrary 1 cm distance on the film is within 30%.

(4) Durability (4-1) Damp heat durability As described in JP-A No. 2001-116922, light transmittance before and after standing in an atmosphere of 60 ° C. and 90% RH for 500 hours The rate of change in the degree of polarization is preferably 3% or less based on the absolute value. In particular, the change rate of the light transmittance is 2% or less, and the change rate of the polarization degree is preferably 1.0% or less, more preferably 0.1% or less based on the absolute value. Further, as described in JP-A-07-0777608, it is also preferred that the degree of polarization after standing for 500 hours at 80 ° C. and 90% RH is 95% or more and the single transmittance is 38% or more.

(4-2) Dry durability It is also preferable that the light transmittance and the change rate of the polarization degree before and after being left in a dry atmosphere at 80 ° C. for 500 hours are 3% or less based on absolute values. . In particular, the change rate of the light transmittance is preferably 2% or less, and the change rate of the polarization degree is preferably 1.0% or less, more preferably 0.1% or less based on the absolute value.

(4-3) Other durability Further, as described in JP-A-06-167611, the shrinkage after standing at 80 ° C. for 2 hours is 0.5% or less, or both surfaces of the glass plate The x and y values after leaving the polarizing plate laminate arranged in crossed Nicols in an atmosphere of 69 ° C. for 750 hours within the range described in JP-A-10-068818, after 200 hours standing process in an atmosphere of RH 90%, the change in spectral intensity ratio of the 105 cm ^-1 and 157cm ^-1 due to Raman spectroscopy, described in JP-a-08-094834 and JP 09-197127 It is also preferable to set the range.

(5) Orientation degree The higher the degree of orientation of PVA, the better the polarization performance, but the range of 0.2 to 1.0 is preferable as the order parameter value calculated by means such as polarization Raman scattering or polarization FT-IR. It is. Further, as described in JP-A-59-133509, the difference between the orientation coefficient of the polymer segment in the entire amorphous region of the polarizer and the orientation coefficient of the occupied molecule (0.75 or more) is at least 0. .15, or as described in JP 04-204907 A, the orientation coefficient of the amorphous region of the polarizer is 0.65 to 0.85, or a higher order of I ₃ ⁻ or I ₅ ⁻ . It is also preferable to adjust the degree of orientation of iodine ions to 0.8 to 1.0 as an order parameter value.

(6) Other characteristics As described in JP-A-2002-006133, the contraction force in the absorption axis direction per unit width when heated at 80 ° C. for 30 minutes is 4.0 N / cm or less. As described in JP-A No. 2002-236213, when the polarizing plate is placed under heating at 70 ° C. for 120 hours, the dimensional change rate in the absorption axis direction and the dimensional change in the polarizing axis direction of the polarizing plate It is also preferable to make the ratios both within ± 0.6%, or to set the moisture content of the polarizing plate to 3% by mass or less as described in JP-A-2002-090546. Further, as described in Japanese Patent Application Laid-Open No. 2000-249832, the surface roughness in the direction perpendicular to the stretching axis is 0.04 μm or less based on the center line average roughness, or Japanese Patent Application Laid-Open No. 10-268294. As described in JP-A-10-111411, the refractive index n ₀ in the transmission axis direction is made larger than 1.6, or the relationship between the thickness of the polarizing plate and the thickness of the protective film is It can also be preferably performed.

[Functionalization of polarizing plate]
The polarizing plate of the present invention includes an LCD viewing angle widening film, a retardation film such as a λ / 4 plate for application to a reflective LCD, an antireflection film for improving display visibility, a brightness enhancement film, It is preferably used as a functionalized polarizing plate combined with an optical film having functional layers such as a coat layer, a forward scattering layer, and an antiglare (antiglare) layer.

A configuration example in which the polarizing plate of the present invention is combined with the above functional optical film is shown in FIG.
As a protective film on one side of the polarizing plate 5, the functional optical film 3 may be adhered to the polarizer 2 via an adhesive layer (not shown) (FIG. 1A), and protection is provided on both sides of the polarizer 2. The functional optical film 3 may be bonded to the polarizing plate 5 provided with the films 1a and 1b through the adhesive layer 4 (FIG. 1B). In the former case, an arbitrary protective film is used for one protective film 1, and the other is sandwiched between the polarizer 2 and the optical functional layer is bonded to the cellulose acylate film of the present invention via an adhesive layer. It is also preferable to adopt the configuration of FIG. The peel strength between layers such as a functional layer and a protective film is preferably 4.0 N / 25 mm or more described in JP-A-2002-311238. The functional optical film can be preferably disposed on the liquid crystal module side or on the opposite side of the liquid crystal module, that is, on the display side or the backlight side, depending on the intended function.

  The functional optical film used in combination with the polarizing plate of the present invention will be described below.

(1) Viewing Angle Enlargement Film The polarizing plate of the present invention includes TN (Twisted Nematic), IPS (In-Plane Switching), OCB (Optically Compensatory).
Bend), VA (Vertically Aligned), and ECB (Electrically Controlled Birefringence) can be used in combination with a viewing angle widening film proposed for display modes.

  As a viewing angle widening film for the TN mode, “Journal of the Japan Printing Society” Vol. 36, No. 3 (1999) p. 40-44, “Monthly Display” August issue (2002) p. 20-24, WV films described in JP-A-4-229828, JP-A-6-75115, JP-A-6-214116, JP-A-8-50206, etc. {manufactured by Fuji Photo Film Co., Ltd. } Are preferably used in combination.

  A preferred configuration of the viewing angle widening film for the TN mode has an alignment layer and an optically anisotropic layer in this order on a transparent polymer film. The viewing angle widening film may be used by being bonded to a polarizing plate through an adhesive, but “SID'00 Dig.”, P. As described in 551 (2000), it is particularly preferable from the viewpoint of thinning that it is used also as one of the protective films of the polarizer.

  The alignment layer can be provided by means such as a rubbing treatment of an organic compound (preferably a polymer), oblique deposition of an inorganic compound, or formation of a layer having a microgroup. Furthermore, an alignment layer in which an alignment function is generated by application of an electric field, application of a magnetic field, or light irradiation is also known, but an alignment layer formed by a rubbing treatment of a polymer is particularly preferable. The rubbing treatment is preferably performed by rubbing the surface of the polymer layer several times in a certain direction with paper or cloth. It is preferable that the absorption axis direction and the rubbing direction of the polarizer are substantially parallel. As the polymer used for the alignment layer, polyimide, polyvinyl alcohol, a polymer having a polymerizable group described in JP-A-9-152509, and the like can be preferably used. The thickness of the alignment layer is preferably 0.01 to 5 μm, and more preferably 0.05 to 2 μm.

The optically anisotropic layer preferably contains a liquid crystalline compound. The liquid crystalline compound used in the present invention particularly preferably has a discotic compound (discotic liquid crystal). The discotic liquid crystal molecule has a disk-like core portion like a triphenylene derivative, and has a structure in which side chains extend radially therefrom. In order to impart stability over time, it is also preferable to further introduce a group that reacts with heat, light or the like. Preferred examples of the discotic liquid crystal are described in JP-A-8-50206.
Examples of discotic liquid crystal molecules are shown below.

  Near the alignment layer, the discotic liquid crystal molecules are aligned almost parallel to the film plane with a pretilt angle in the rubbing direction, and on the opposite air surface side, the discotic liquid crystal molecules stand in a form that is nearly perpendicular to the surface. Oriented. The discotic liquid crystal layer as a whole has a hybrid alignment, and this layer structure can realize a wide viewing angle of a TN mode TFT-LCD.

  The optically anisotropic layer is generally formed by applying a solution of a discotic compound and other compounds (for example, a polymerizable monomer, a photopolymerization initiator, etc.) dissolved in a solvent onto the alignment layer, drying it, After heating to the temperature at which the tick nematic phase is formed, polymerization is performed by irradiation with UV light or the like, followed by cooling. The discotic nematic liquid crystal phase-solid phase transition temperature of the discotic liquid crystalline compound used in the present invention is preferably 70 to 300 ° C, particularly preferably 70 to 170 ° C.

In addition to the discotic compound added to the optically anisotropic layer, the compound has compatibility with the discotic compound and can give a preferable change in tilt angle to the liquid crystalline discotic compound or inhibit the alignment. Any compound can be used as long as it is not. Among these, polymerizable monomers (for example, compounds having a vinyl group, vinyloxy group, acryloyl group and methacryloyl group), additives for controlling the orientation on the air interface side such as fluorine-containing triazine compounds, cellulose acetate, cellulose acetate propio And polymers such as nates, hydroxypropylcellulose and cellulose acetate butyrate. These compounds are generally used in an amount of 0.1 to 50% by mass, preferably 0.1 to 30% by mass, based on the discotic compound.
The thickness of the optically anisotropic layer is preferably 0.1 to 10 μm, and more preferably 0.5 to 5 μm.

  A preferred embodiment of the viewing angle widening film comprises a cellulose acylate film as a transparent substrate film, an alignment layer provided thereon, and an optically anisotropic layer comprising a discotic liquid crystal formed on the alignment layer. In addition, the optically anisotropic layer is crosslinked by UV light irradiation.

  In addition to the above, when the viewing angle widening film and the polarizing plate of the present invention are combined, for example, as described in Japanese Patent Application Laid-Open No. 07-198942, it has an optical axis in a direction intersecting the plate surface. Laminating with a retardation plate exhibiting birefringence anisotropy, or as described in JP-A-2002-258052, the dimensional change rate of the protective film and the optically anisotropic layer is substantially the same. It can also be preferably performed. Further, as described in JP-A-12-258632, the polarizing plate to be bonded to the viewing angle widening film has a moisture content of 2.4% or less, or described in JP-A-2002-267839. As can be seen, the contact angle of the viewing angle widening film surface with water can be preferably set to 70 ° or less.

The viewing angle widening film for an IPS mode liquid crystal cell is used for optical compensation of liquid crystal molecules aligned in parallel to the substrate surface and improvement of viewing angle characteristics of the orthogonal transmittance of the polarizing plate during black display in the absence of an electric field. In the IPS mode, black is displayed when no electric field is applied, and the transmission axes of the pair of upper and lower polarizing plates are orthogonal. However, when observed from an oblique direction, the crossing angle of the transmission axes is not 90 °, and leakage light is generated, resulting in a decrease in contrast. When the polarizing plate of the present invention is used in an IPS mode liquid crystal cell, the in-plane retardation is close to 0 and the thickness direction is reduced as described in JP-A-10-54982 to reduce leakage light. Are preferably used in combination with a viewing angle widening film having a phase difference.

  The OCB mode viewing angle widening film for liquid crystal cells is intended to improve the viewing angle characteristics of black display by optically compensating the liquid crystal layer that is vertically aligned at the center of the liquid crystal layer by applying an electric field and tilted near the substrate interface. used. When the polarizing plate of the present invention is used in an OCB mode liquid crystal cell, a discotic liquid crystalline compound as described in US Pat. No. 5,805,253 is preferably used in combination with a viewing angle widening film that is hybrid-aligned.

  The viewing angle widening film for liquid crystal cells in the VA mode improves the viewing angle characteristics of black display in a state where liquid crystal molecules are vertically aligned with respect to the substrate surface in the absence of an electric field. As such a viewing angle widening film, a film having an in-plane retardation close to 0 and having a retardation in the thickness direction as described in Japanese Patent No. 2866372, A film in which the compound is arranged in parallel to the substrate, a stretched film having the same in-plane retardation value, a film in which the slow axes are perpendicular to each other, and prevention of deterioration of orthogonal transmittance in the oblique direction of the polarizing plate Therefore, it is preferably used in combination with a laminate of films made of rod-like compounds such as liquid crystal molecules.

(2) Retardation film The polarizing plate of the present invention preferably has a retardation layer. The retardation layer in the present invention is preferably a λ / 4 plate, and can be used as a circularly polarizing plate by laminating the polarizing plate of the present invention and the λ / 4 plate. The circularly polarizing plate has a function of converting incident light into circularly polarized light, and is preferably used for a reflective liquid crystal display device, a transflective liquid crystal display device such as an ECB mode, or an organic EL element.

The λ / 4 plate used in the present invention is a retardation film having a retardation (Re) of approximately ¼ of the wavelength in the visible light wavelength range in order to obtain almost perfect circularly polarized light in the visible light wavelength range. It is preferable that “Retardation of approximately ¼ in the wavelength range of visible light” means that the longer the wavelength, the larger the retardation in the wavelength range from 400 to 700 nm, and the retardation value (Re ₄₅₀ ) measured at a wavelength of 450 nm is 80 to 125 nm. In addition, a range satisfying a relationship in which a retardation value (Re ₅₉₀ ) measured at a wavelength of 590 nm is 120 to 160 nm is shown. Still more preferably Re ₅₉₀ -Re ₄₅₀ ≧ 5nm, particularly preferably Re ₅₉₀ -Re ₄₅₀ ≧ 10nm.

  The λ / 4 plate used in the present invention is not particularly limited as long as it satisfies the above-mentioned conditions. For example, it is described in JP-A-5-27118, JP-A-10-68816, and JP-A-10-90521. A λ / 4 plate obtained by laminating a plurality of polymer films, a λ / 4 plate obtained by stretching one polymer film described in WO00 / 65384 pamphlet, WO00 / 26705 pamphlet, A known λ / 4 plate such as a λ / 4 plate described in JP 2000-284126 A and JP 2002-31717 A, in which at least one optically anisotropic layer is provided on a polymer film, is used. be able to. Moreover, the direction of the slow axis of the polymer film and the orientation direction of the optically anisotropic layer can be arranged in any direction according to the liquid crystal cell.

  In the circularly polarizing plate, the slow axis of the λ / 4 plate and the transmission axis of the polarizer can intersect at an arbitrary angle, but preferably intersect within a range of 45 ° ± 20 °. However, the slow axis of the λ / 4 plate and the transmission axis of the polarizer may intersect within a range other than the above.

When the λ / 4 plate is formed by laminating the λ / 4 plate and the λ / 2 plate, as described in Japanese Patent No. 3236304 and Japanese Patent Laid-Open No. 10-68816, the λ / 4 plate and The λ / 2 plate is preferably bonded so that the angle between the slow axis in the plane of the λ / 2 plate and the transmission axis of the polarizing plate is substantially 75 ° and 15 °.

(3) Antireflection film The polarizing plate of the present invention can be used in combination with an antireflection film. As the antireflection film, either a film having a reflectivity of about 1.5% only by applying a single layer of a low refractive index material such as a fluoropolymer, or a film having a reflectivity of 1% or less using multilayer interference of a thin film is used. it can.

  In the present invention, a structure in which a low refractive index layer and at least one layer having a higher refractive index than that of the low refractive index layer (that is, a high refractive index layer and a medium refractive index layer) is laminated on the transparent support is preferably used. Is done. Further, an antireflection film described in “Nitto Technical Report” Vol. 38, No. 1 (May) (2000), pages 26 to 28, JP-A No. 2002-301783 and the like can also be preferably used.

The refractive index of each layer satisfies the following relationship.
Refractive index of high refractive index layer> refractive index of medium refractive index layer> refractive index of transparent support> refractive index of low refractive index layer

  As the transparent support used for the antireflection film, a polymer film used for the protective film of the polarizer can be preferably used.

(Low refractive index layer)
The refractive index of the low refractive index layer is 1.20 to 1.55, preferably 1.30 to 1.50. The low refractive index layer is preferably used as an outermost layer having scratch resistance and antifouling properties. In order to improve the scratch resistance, it is also preferable to impart slipperiness to the surface using a material containing a silicone group or fluorine.

  Examples of the fluorine-containing compound include paragraph numbers [0018] to [0026] of JP-A-9-222503, paragraph numbers [0019] to [0030] of JP-A-11-38202, and paragraph numbers of JP-A-2001-40284. [0027] to [0028], compounds described in JP-A No. 2000-284102 and the like can be preferably used.

  The silicone-containing compound is preferably a compound having a polysiloxane structure, but reactive silicone [for example, “Silaplane” {manufactured by Chisso Corporation]] or polysiloxane having silanol groups at both ends (Japanese Patent Laid-Open No. 11-258403) ) Etc. can also be used. An organometallic compound such as a silane coupling agent and a specific fluorine-containing hydrocarbon group-containing silane coupling agent may be cured by a condensation reaction in the presence of a catalyst (Japanese Patent Laid-Open No. 58-142958, the same as above). 58-147483, 58-147484, JP-A-9-157582, 11-106704, JP-A-2000-117902, 2001-48590, 2002-53804 And the like).

  In the low refractive index layer, as an additive other than the above, the average primary particle diameter of fillers (for example, silicon dioxide (silica), fluorine-containing particles (magnesium fluoride, calcium fluoride, barium fluoride)) is 1 -150 nm low refractive index inorganic compound (organic fine particles described in paragraph Nos. [0020] to [0038] of JP-A No. 11-3820), silane coupling agent, slip agent, surfactant, etc. Can also be preferably performed.

The low refractive index layer may be formed by a vapor phase method (vacuum deposition method, sputtering method, ion plating method, plasma CVD method, etc.), but is preferably formed by a coating method because it can be manufactured at low cost. . As the coating method, dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, and micro gravure can be preferably used.

  The film thickness of the low refractive index layer is preferably 30 to 200 nm, more preferably 50 to 150 nm, and most preferably 60 to 120 nm.

(Medium refractive index layer and high refractive index layer)
The medium refractive index layer and the high refractive index layer preferably have a structure in which ultrafine particles of high refractive index having an average particle diameter of 100 nm or less are dispersed in a matrix material. Inorganic compound fine particles having a high refractive index include inorganic compounds having a refractive index of 1.65 or more, for example, oxides such as Ti, Zn, Sb, Sn, Zr, Ce, Ta, La, and In, and metal atoms thereof. A composite oxide or the like can be preferably used.

  Such ultrafine particles may be obtained by treating the particle surface with a surface treatment agent (silane coupling agent, etc .: JP-A Nos. 11-295503, 11-153703, 2000-9908, anionic compounds) Or an organic metal coupling agent: JP-A-2001-310432 or the like, or a core-shell structure with a high refractive index particle as a core (JP-A-2001-166104, etc.), or a specific dispersant (for example, JP-A-11-153703, US Pat. No. 6,210,858, JP-A-2002-27776069, etc.) can be used.

  As the matrix material, conventionally known thermoplastic resins, curable resin films, and the like can be used, but JP-A-2000-47004, 2001-315242, 2001-31871, and 2001-296401. It is also possible to use a curable film obtained from a polyfunctional material described in a gazette or the like or a metal alkoxide composition described in JP-A-2001-293818 or the like.

  The refractive index of the high refractive index layer is preferably 1.70 to 2.20. The thickness of the high refractive index layer is preferably 5 nm to 10 μm, and more preferably 10 nm to 1 μm.

  The refractive index of the middle refractive index layer is adjusted to be a value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. The refractive index of the middle refractive index layer is preferably 1.50 to 1.70.

  The haze of the antireflection film is preferably 5% or less, more preferably 3% or less. Further, the hardness of the film is preferably H or more, more preferably 2H or more, and most preferably 3H or more in a pencil hardness test according to JIS K-5400.

(4) Brightness improving film The polarizing plate of this invention can be used in combination with a brightness improving film. The brightness enhancement film has a function of separating circularly polarized light or linearly polarized light, and is disposed between the polarizing plate and the backlight, and reflects or backscatters one circularly polarized light or linearly polarized light to the backlight side. The re-reflected light from the backlight part partially changes the polarization state and partially transmits when it re-enters the brightness enhancement film and the polarizing plate. By repeating this process, the light utilization rate is improved. The front luminance is improved to about 1.4 times. As the brightness enhancement film, an anisotropic reflection method and an anisotropic scattering method are known, and both can be combined with the polarizing plate of the present invention.

In the anisotropic reflection method, a brightness enhancement film having anisotropy in reflectance and transmittance is known by laminating a uniaxially stretched film and an unstretched film in multiple layers to increase the refractive index difference in the stretching direction. Multi-layer systems using the principle of dielectric mirrors (described in pamphlets of International Publication Nos. 95/17691, 95/17692, 95/17699) and cholesteric liquid crystal systems (European Patent No. No. 606940A2 and JP-A-8-271731) are known. Multi-layer brightness enhancement films using the principle of dielectric mirrors are DBEF-E, DBEF-D, DBEF-M (all manufactured by 3M), and cholesteric liquid crystal brightness enhancement films are NIPOCS {Nitto Denko Made by Co., Ltd.} is preferably used in the present invention. Regarding NIPOCS, “Nitto Technical Report”, Vol. 38, No. 1 (May), 2000, pages 19 to 21 can be referred to.

  In the present invention, the pamphlets of International Publication Nos. 97/32223, 97/32224, 97/32225, 97/32226, and JP-A-9-274108 and 11-174231 are used. It is also preferable to use in combination with a brightness enhancement film of an anisotropic scattering method, which is described in each publication and blended with a positive intrinsic birefringent polymer and a negative intrinsic birefringent polymer and uniaxially stretched. As the anisotropic scattering system brightness enhancement film, DRPF-H (manufactured by 3M) is preferable.

  The polarizing plate and the brightness enhancement film of the present invention are preferably used as an integrated type in which one of the polarizing film and the protective film of the polarizing plate is bonded via an adhesive.

(5) Other functional optical films The polarizing plate of the present invention further includes a hard coat layer, a forward scattering layer, an antiglare (antiglare) layer, a gas barrier layer, a sliding layer, an antistatic layer, an undercoat layer, a protective layer, and the like. It is also preferred to use it in combination with a functional optical film provided with These functional layers are preferably used in combination with each other in the same layer as the antireflection layer in the antireflection film or the optically anisotropic layer in the viewing angle widening film. These functional layers can be used by providing them on one side or both sides of the anti-reflective film or viewing angle compensation film on the side of the polarizer or the side opposite to the polarizer (the side on the air side).

(5-1) Hard Coat Layer The polarizing plate of the present invention is preferably combined with a functional optical film provided with a hard coat layer on the surface of the transparent support in order to impart mechanical strength such as scratch resistance. Is called. When the hard coat layer is applied to the antireflection film, it is particularly preferable to provide it between the transparent support and the high refractive index layer.

  The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of the curable compound by light and / or heat. The curable functional group is preferably a photopolymerizable functional group, and the hydrolyzable functional group-containing organometallic compound is preferably an organic alkoxysilyl compound. As a specific constituent composition of the hard coat layer, for example, those described in JP-A-2002-144913, JP-A-2000-9908, WO 00/46617, etc. can be preferably used.

The film thickness of the hard coat layer is preferably 0.2 to 100 μm.
The hardness of the hard coat layer is preferably H or more, more preferably 2H or more, and most preferably 3H or more in a pencil hardness test according to JIS K-5400. Further, in the Taber test according to JIS K-5400, the smaller the wear amount of the test piece before and after the test, the better.

As the material for forming the hard coat layer, a compound containing an ethylenically unsaturated group or a compound containing a ring-opening polymerizable group can be used, and these compounds can be used alone or in combination. Preferred examples of the compound containing an ethylenically unsaturated group include ethylene glycol diacrylate, trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol. Polyacrylates of polyols such as hexaacrylate; epoxy acrylates such as diacrylate of bisphenol A diglycidyl ether, diacrylate of hexanediol diglycidyl ether; obtained by reaction of polyisocyanate and hydroxyl group-containing acrylate such as hydroxyethyl acrylate Examples of preferred compounds include urethane acrylates.

  Commercially available compounds include “EB-600”, “EB-40”, “EB-140”, “EB-1150”, “EB-1290K”, “IRR214”, “EB-2220”, “TMPTA”. , “TMPTMA” {above, manufactured by Daicel UCB Co., Ltd.}, “UV-6300”, “UV-1700B” {above, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.}, and the like.

  Preferred examples of the compound containing a ring-opening polymerizable group include ethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, trimethylol ethane triglycidyl ether, trimethylol propane triglycidyl ether, glycerol triglycidyl ether as glycidyl ethers. , Triglycidyl trishydroxyethyl isocyanurate, sorbitol tetraglycidyl ether, pentaerythritol tetraglycyl ether, polyglycidyl ether of cresol novolac resin, polyglycidyl ether of phenol novolac resin, etc .; "Celoxide 2081", "Epolide GT-301", "Epolide GT-401", "EHPE3 150CE "{manufactured by Daicel Chemical Industries, Ltd.}, phenol novolak resin polycyclohexyl epoxy methyl ether, etc .; as oxetanes," OXT-121 "," OXT-221 "," OX-SQ "," PNOX- 1009 "{above, manufactured by Toagosei Co., Ltd.} and the like. In addition, a polymer of glycidyl (meth) acrylate or a copolymer of glycidyl (meth) acrylate and a monomer copolymerizable therewith can be used for the hard coat layer.

  In the hard coat layer, fine particles of oxide such as silicon, titanium, zirconium, and aluminum are used to reduce curing shrinkage of the hard coat layer, improve adhesion to the substrate, and reduce curling of the hard coat treated article of the present invention. It is also preferable to add crosslinked fine particles such as crosslinked fine particles such as polyethylene, polystyrene, poly (meth) acrylic acid esters, polydimethylsiloxane, etc., and fine organic particles such as fine crosslinked rubber particles such as SBR and NBR. The average particle size of these crosslinked fine particles is preferably 1 nm to 20000 nm. Further, the shape of the crosslinked fine particles can be used without particular limitation, such as a spherical shape, a rod shape, a needle shape, or a plate shape. The addition amount of the fine particles is preferably 60% by volume or less, more preferably 40% by volume or less of the hard coat layer after curing.

  When the inorganic fine particles described above are added, these inorganic fine particles generally have poor affinity with the binder polymer. Therefore, these inorganic fine particles contain a metal such as silicon, aluminum, titanium, and the alkoxide group, carboxyl Surface treatment using a surface treatment agent having a functional group such as an acid group, a sulfonic acid group, or a phosphonic acid group is also preferably performed.

  The hard coat layer is preferably cured using heat or active energy rays. Among them, active energy rays such as radiation, gamma rays, alpha rays, electron rays, and ultraviolet rays are more preferred, and safety and productivity are improved. In view of the above, it is particularly preferable to use an electron beam or an ultraviolet ray. In the case of curing with heat, in consideration of the heat resistance of the plastic itself, the heating temperature is preferably 140 ° C. or lower, more preferably 100 ° C. or lower.

(5-2) Forward scattering layer The forward scattering layer is used to improve viewing angle characteristics (hue and luminance distribution) in the vertical and horizontal directions when the polarizing plate of the present invention is applied to a liquid crystal display device. In the present invention, a configuration in which fine particles having different refractive indexes are dispersed in a binder is preferable. The construction of JP-A No. 199809, JP-A No. 2002-107512 or the like that defines the haze value as 40% or more can be used. In addition, in order to control the viewing angle characteristics of haze, the polarizing plate of the present invention is also preferably used in combination with “Lumisty” described in Sumitomo Chemical's technical report “Photofunctional Films” on pages 31-39. be able to.

(5-3) Anti-glare layer The anti-glare (anti-glare) layer is used to scatter reflected light and prevent reflection. The antiglare function is obtained by forming irregularities on the outermost surface (display side) of the liquid crystal display device. The haze of the optical film having an antiglare function is preferably 3 to 30%, more preferably 5 to 20%, and most preferably 7 to 20%.

  The method for forming irregularities on the film surface is, for example, a method of forming irregularities on the film surface by adding fine particles (for example, JP-A No. 2000-271878), relatively large particles (particle size 0.05-2 μm). ) Is added in a small amount (0.1 to 50% by mass) (for example, Japanese Patent Application Laid-Open Nos. 2000-281410, 2000-95893, 2001-100004, and 2001). No. 281407, etc.), a method of physically transferring the uneven shape onto the film surface (for example, as an embossing method, JP-A-63-278839, JP-A-11-183710, JP-A-2000-275401) Etc.) can be preferably used.

[Liquid crystal display device using polarizing plate]
Next, a liquid crystal display device in which the polarizing plate of the present invention is used will be described.
In the liquid crystal display device of the present invention having the liquid crystal cell and two polarizing plates disposed on both sides thereof, at least one polarizing plate is the polarizing plate of the present invention.
FIG. 2 is an example of a liquid crystal display device in which the polarizing plate of the present invention is used.

The liquid crystal display device of the present invention shown in FIG. 2 includes a liquid crystal cell (10-13), and an upper polarizing plate 6 and a lower polarizing plate 17 that are disposed with the liquid crystal cell (10-13) interposed therebetween. The polarizing plate is sandwiched between a polarizer and a pair of protective films, but is shown as an integrated polarizing plate in FIG. The liquid crystal cell includes a liquid crystal layer formed of an upper electrode substrate 10 and a lower electrode substrate 13 and liquid crystal molecules 12 sandwiched therebetween. The liquid crystal cell is different in the alignment state of liquid crystal molecules that perform ON / OFF display. However, the polarizing plate of the present invention can be used in any display mode regardless of the transmissive and reflective types.
Among these display modes, the OCB mode or the VA mode is preferable.

  An alignment film (not shown) is formed on the surfaces of the electrode substrates 10 and 13 that are in contact with the liquid crystal molecules 12 (hereinafter may be referred to as “inner surface”), and is formed by a rubbing process or the like applied on the alignment film. The orientation of the liquid crystal molecules 12 in a state where no electric field is applied or a state where a low voltage is applied is controlled. Further, on the inner surfaces of the substrates 10 and 13, a transparent electrode (not shown) capable of applying an electric field to the liquid crystal layer made of the liquid crystal molecules 12 is formed.

  The rubbing direction of the TN mode is applied in directions perpendicular to each other on the upper and lower substrates, and the magnitude of the tilt angle can be controlled by the strength and the number of rubbing times. The alignment film is formed by applying and baking a polyimide film. The magnitude of the twist angle (twist angle) of the liquid crystal layer is determined by the crossing angle of the upper and lower substrates in the rubbing direction and the chiral agent added to the liquid crystal material. Here, a chiral agent having a pitch of about 60 μm is added so that the twist angle becomes 90 °.

  The twist angle is in the vicinity of 90 ° (85 to 95 °) in the case of a notebook computer, a personal computer monitor, and a liquid crystal display device for a television, and is 0 to 70 ° in the case of use as a reflective display device such as a mobile phone. Set. In the IPS mode and the ECB mode, the twist angle is 0 °. In the IPS mode, electrodes are disposed only on the lower substrate 8 and an electric field parallel to the substrate surface is applied. In the OCB mode, there is no twist angle and the tilt angle is increased, and in the VA mode, the liquid crystal molecules 12 are aligned perpendicular to the upper and lower substrates.

  Here, the magnitude of the product Δnd of the thickness d of the liquid crystal layer and the refractive index anisotropy Δn changes the brightness during white display. Therefore, in order to obtain the maximum brightness, the range is set for each display mode.

  High contrast can be obtained by laminating so that the crossing angle of the absorption axis 7 of the upper polarizing plate 6 and the absorption axis 18 of the lower polarizing plate 17 is generally orthogonal. The crossing angle between the absorption axis 7 of the upper polarizing plate 6 of the liquid crystal cell and the rubbing direction of the upper substrate 10 varies depending on the liquid crystal display mode, but is generally set to be parallel or vertical in the TN and IPS modes. In OCB and ECB modes, it is often set to 45 °. However, the optimum value differs in each display mode for adjusting the color tone and viewing angle of the display color, and the present invention is not limited to this range.

  The liquid crystal display device in which the polarizing plate of the present invention is used is not limited to the configuration of FIG. 2, and may include other members. For example, a color filter may be disposed between the liquid crystal cell and the polarizer. Moreover, the viewing angle widening film mentioned above can also be separately arranged between the liquid crystal cell and the polarizing plate. The polarizing plates 6 and 17 and the optically anisotropic layers (viewing angle widening films) 8 and 15 may be arranged in a laminated form bonded with an adhesive, and one of the liquid crystal cell side protective films is used for widening the viewing angle. It may be arranged as a so-called integrated elliptical polarizing plate.

  When the liquid crystal display device using the polarizing plate of the present invention is used as a transmission type, a backlight using a cold cathode or a hot cathode fluorescent tube, or a light emitting diode, a field emission element, or an electroluminescent element as a light source. Can be placed on the back. Further, the liquid crystal display device in which the polarizing plate of the present invention is used may be of a reflective type. In such a case, only one polarizing plate may be disposed on the observation side, and the back of the liquid crystal cell or under the liquid crystal cell. A reflective film is installed on the inner surface of the side substrate. Of course, a front light using the light source may be provided on the liquid crystal cell observation side.

  EXAMPLES Hereinafter, although this invention is described concretely based on an Example and a synthesis example, this invention is not limited at all by these specific examples.

[Synthesis of retardation increasing agent]
Synthesis Example 1: Synthesis of Exemplified Compound (A-1) In a 1000 mL reaction vessel equipped with a stirrer, raw material addition apparatus, reflux condenser and thermometer, 40.1 g (189 mmol) of 2,4,5-trimethoxybenzoic acid, After charging 16.75 g (90 mmol) of 4,4′-dihydroxybiphenyl, 200 mL of toluene and 2 mL of dimethylformamide and heating to 70 ° C., 23.6 g (198 mmol) of thionyl chloride was slowly added dropwise at 70 ° C. The mixture was heated and stirred for 2.5 hours. Thereafter, the reaction solution was cooled to room temperature, 300 mL of methanol was added, and the precipitated crystals were collected by filtration to obtain 48.4 g (yield 94%) of the target compound as white crystals. The compound was identified by ¹ H-NMR (400 MHz).
¹ H-NMR (CDCl ₃ ): δ 3.93 (s, 6H), 3.95 (s, 6H), 3.99 (s, 6H), 6.58 (s, 2H), 7.28 (d , 4H), 7.62 (m, 6H).
The melting point of the obtained compound was 227 to 229 ° C.

Synthesis Example 2: Synthesis of Exemplary Compound (A-2) In a reaction vessel similar to that used in Synthesis Example 1, 34 g (160 mmol) of 2,4,5-trimethoxybenzoic acid, 4,4′-dihydroxy-3-fluoro After charging 15 g (73 mmol) of biphenyl, 110 mL of toluene and 1.6 mL of dimethylformamide and heating to 70 ° C., 20.9 g (176 mmol) of thionyl chloride was slowly added dropwise and stirred at 70 ° C. for 2.5 hours. did. Thereafter, the reaction solution was cooled to room temperature, 300 mL of methanol was added, and the precipitated crystals were collected by filtration to obtain 37 g (yield 86%) of the target compound as white crystals. The compound was identified by ¹ H-NMR (400 MHz).
¹ H-NMR (CDCl ₃ ): δ 3.93 (s, 6H), 3.95 (s, 6H), 4.00 (s, 6H), 6.59 (s, 2H), 7.26-7 .45 (m, 5H), 7.63 (m, 4H).
The melting point of the obtained compound was 197 to 199 ° C.

Synthesis Example 3: Synthesis of Exemplary Compound (A-3) In a reaction vessel similar to that used in Synthesis Example 1, 23.3 g (110 mmol) of 2,4,5-trimethoxybenzoic acid and 4,4′-dihydroxy-3 -Chlorobiphenyl (15 g, 50 mmol), toluene (75 mL) and dimethylformamide (1.1 mL) were charged and heated to 70 ° C., and then thionyl chloride (14.4 g, 121 mmol) was slowly added dropwise at 80 ° C. for 2.5 hours. Stir with heating. Thereafter, the reaction solution was cooled to room temperature, 250 mL of methanol was added, and the precipitated crystals were collected by filtration to obtain 26 g (yield 85%) of the target compound as white crystals. The compound was identified by ¹ H-NMR (400 MHz).
¹ H-NMR (CDCl ₃ ): δ 3.90-4.00 (m, 18H), 6.59 (s, 2H), 7.26-7.70 (m, 9H).
The melting point of the obtained compound was 168 to 170 ° C.

Synthesis Example 4: Synthesis of Exemplary Compound (A-4) In a reaction vessel similar to that used in Synthesis Example 1, 30.3 g (143 mmol) of 4,4,5-trimethoxybenzoic acid and 4,4′-dihydroxy-3 -After charging 15 g (65 mmol) of methylbiphenyl, 100 mL of toluene and 1.4 mL of dimethylformamide and heating to 70 ° C, 18.7 g (157 mmol) of thionyl chloride was slowly added dropwise and the mixture was stirred at 70 ° C for 2.5 hours. Stir with heating. Thereafter, the reaction solution was cooled to room temperature, 300 mL of methanol was added, and the precipitated crystals were collected by filtration to obtain 27.4 g (yield 72%) of the target compound as white crystals. The compound was identified by ¹ H-NMR (400 MHz).
¹ H-NMR (CDCl ₃ ): δ 2.31 (s, 3H), 3.95 (s, 6H), 4.00 (s, 6H), 6.60 (s, 2H), 7.10 (m , 2H), 7.27 (m, 3H), 7.40 (m, 2H), 7.63 (d, 2H) mass spectrum: m / z 589 (M + H) ⁺ .
The melting point of the obtained compound was 188 to 189 ° C.

Synthesis Example 5: Synthesis of Exemplary Compound (A-6) In a reaction vessel similar to that used in Synthesis Example 1, 5.72 g (26.9 mmol) of 2,4,5-trimethoxybenzoic acid and 3.5 g of diisopropylethylamine ( 27 mmol) and 20 mL of tetrahydrofuran, and cooled with ice water, methanesulfonyl chloride 3.1.
g (27 mmol) was slowly added dropwise, followed by stirring at room temperature for 2 hours. After cooling to ice water, a solution prepared by dissolving 2.9 g (13.7 mmol) of bis (4-hydroxyphenyl) acetylene and 3.5 g (27 mmol) of diisopropylethylamine in 40 mL of tetrahydrofuran was slowly added. The mixture was stirred at room temperature for 3 hours and at 50 ° C. for 1 hour. Thereafter, 160 mL of water was added, and the obtained crystals were filtered and collected, 100 mL of methanol was added, recrystallization operation was performed, and the precipitated crystals were filtered and collected to obtain 3.0 g of the target compound as white crystals (yield 19%). The compound was identified by ¹ H-NMR (400 MHz) and mass spectrum.
¹ H-NMR (CDCl ₃ ): δ 3.93 (s, 6H), 3.95 (s, 6H), 3.99 (s, 6H), 6.57 (s, 2H), 7.24 (m , 4H), 7.58 (m, 6H).
Mass spectrum: m / z 599 (M + H) ⁺
The melting point of the obtained compound was 201 to 203 ° C.

Synthesis Example 6: Synthesis of Exemplified Compound (A-7) (6-1) Synthesis of 2,4,5-trimethoxybenzoic acid-4-ethynylanilide Into the same reaction vessel as used in Synthesis Example 1, After charging 21.2 g (100 mmol) of 5-trimethoxybenzoic acid, 12.9 g (100 mmol) of diisopropylethylamine and 126 mL of tetrahydrofuran and cooling with ice water, 11.4 g (100 mmol) of methanesulfonyl chloride was slowly added dropwise. The mixture was stirred at room temperature for 2 hours after dropping. Thereafter, the mixture was cooled to ice water, and a solution prepared by dissolving 11.7 g (100 mmol) of 4-ethylaniline and 12.9 g (100 mmol) of diisopropylethylamine in 42 mL of tetrahydrofuran was slowly added, and the mixture was stirred at room temperature for 6 hours. did. Thereafter, 200 mL of ethyl acetate was added, and the organic phase was washed with water, a saturated aqueous sodium hydrogen carbonate solution, a 0.5 mol / L aqueous hydrochloric acid solution, and saturated brine in this order. Sodium sulfate was added to the organic phase, dehydration was performed, sodium sulfate was removed by filtration, and the organic solvent was distilled off under reduced pressure. Next, 350 mL of methanol was added and recrystallization was performed, and the precipitated crystals were collected by filtration to obtain 15.0 g (yield 48%) of the target compound as white crystals.

(6-2) Synthesis of Exemplary Compound (A-7) In the same reaction vessel as used in Synthesis Example 1, 2,4,5-trimethoxybenzoic acid-4-ethynylanilide obtained in (6-1) above was added. Charged with 3.1 g (10 mmol), 2,4,5-trimethoxybenzoic acid 4-iodophenyl 4.1 g (10 mmol), triethylamine 5.56 mL (40 mmol) and tetrahydrofuran 15 mL, under nitrogen atmosphere at room temperature And 22.8 mg (0.12 mmol) of cuprous chloride, 131 mg (0.5 mmol) of triphenylphosphine and 70 mg (0.1 mmol) of bis (triphenylphosphine) palladium dichloride were added, And stirred for 3 hours. Thereafter, the reaction solution was cooled to room temperature, and 200 mL of water was added. The obtained crystals were filtered and recrystallized with 100 mL of methanol to obtain 5.6 g (yield 94%) of the target compound as yellowish white crystals. The compound was identified by ¹ H-NMR (400 MHz).
¹ H-NMR (DMSO-d ₆ ): δ 3.92 (s, 3H), 3.93 (s, 3H), 4.05 (m, 9H) 4.15 (s, 3H) 6.96 (br , 2H), 7.46 (d, 2H), 7.55 (s, 1H), 7.62 (s, 1H), 7.69 (d, 2H), 7.76 (d, 2H), 7 .98 (d, 2H), 10.30 (s, 1H).
The melting point of the obtained compound was 216 to 218 ° C.

[Preparation of cellulose acylate film]
Hereinafter, Examples 1-1 to 1-3, 1-7, 1-8, 1-10 to 1-12, 1-14, 1-15, 11-1 to 11-3, 11-7, 11- 8, 11-10 to 11-12, 21-1 and 21-2 are Reference Examples 1-1 to 1-3, 1-7, 1-8, 1-10 to 1-12 and 1-14, respectively. 1-15, 11-1 to 11-3, 11-7, 11-8, 11-10 to 11-12, 21-1 and 21-2.
Example 1-1: Production of Cellulose Acylate Film (CAF1) [Preparation of Cellulose Acylate Solution]
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose acylate solution.

(Composition of cellulose acylate solution)
Cellulose acetate (CA-1) 100.0 parts by mass Acetylation degree 2.8
Plasticizer: Triphenyl phosphate 6.0 parts by mass Plasticizer: Biphenyl phosphate 3.0 parts by mass Methylene chloride (first solvent) 402.0 parts by mass Methanol (second solvent) 60.0 parts by mass

[Preparation of matting agent solution]
The following composition was charged into a disperser and stirred to dissolve each component to prepare a matting agent solution.

(Matting agent solution composition)
Silica particles having an average particle size of 20 nm 2.0 parts by mass
"AEROSIL R972" manufactured by Nippon Aerosil Co., Ltd. Methylene chloride (first solvent) 75.0 parts by weight Methanol (second solvent) 12.7 parts by weight Cellulose acylate solution 10.3 parts by weight

[Preparation of retardation increasing agent solution]
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a retardation increasing agent solution.

(Composition of retardation increasing agent solution)
Retardation increasing agent (A-1) 20.0 parts by mass Methylene chloride (first solvent) 58.4 parts by mass Methanol (second solvent) 8.7 parts by mass Cellulose acylate solution 12.8 parts by mass

  94.3 parts by mass of the cellulose acylate solution, 1.3 parts by mass of the matting agent solution and 4.4 parts by mass of the retardation increasing agent solution were respectively filtered and mixed, and cast using a band casting machine. The web obtained with a residual solvent content of 35% by mass was peeled from the band, and stretched at a stretching rate of 30% / min up to a stretching ratio of 25% using a tenter at 140 ° C., and then stretched at 23%. The magnification was maintained at 140 ° C. for 30 seconds. Thereafter, the clip was removed and dried at 140 ° C. for 40 minutes to produce a cellulose acylate film (CAF1). The finished cellulose acylate film had a residual solvent amount of 0.2% by mass and a film thickness of 80 μm.

Examples 1-2 to 1-15 and Comparative Examples 1-1 to 1-2: Production of Cellulose Acylate Films (CAF 2 to 15 and CAFR 1 to 2) In Example 1-1, the types and retardations of cellulose acylate Cellulose acylate film (CAF 2-15) in the same manner as in Example 1-1, except that the type of the raising agent, the addition amount, the draw ratio, the draw speed, the draw ratio of the relaxation step, and the time were changed to the contents shown in Table 2. ) And (CAFR1-2).

In Table 2 above, details of the cellulose acylate and retardation increasing agent are shown in Table 3. In addition, the distance between the terminals of the molecule of the retardation increasing agent and the polarizability anisotropy were measured as follows.

[Distance between molecular ends and polarizability anisotropy]
The end-to-end distance and polarizability anisotropy of the molecule were calculated using “Gaussian 03” (Rev. B.03) (software manufactured by Gaussian, USA). The end-to-end distance was calculated as the distance between the most distant atoms after structural optimization by calculation at the B3LYP / 6-31G * level. The polarizability anisotropy is calculated using the structure optimized at the B3LYP / 6-31G * level, the polarizability is calculated at the B3LYP / 6-311 + G ** level, and the obtained polarizability tensor is diagonalized. Calculated from the diagonal component.

In Table 2 and Table 3 above, Compound (I-2) ^{* 2} and Compound (10) ^{* 3} are those of Example Compound (I-2) and JP-A 2002-363343 of JP-A No. 2003-344655, respectively. It is an exemplary compound (10) and is a compound which has the following structural formula.
In Tables 2 and 3, the exemplified compound (15) is the exemplified compound (15) described in Table 1.

[Measurement of optical properties of film]
Using an automatic birefringence meter “KOBRA-21ADH” (manufactured by Oji Scientific Instruments), Re and Rth at 11 points in the width direction were measured at 25 ° C. and 60% RH. The measurement wavelength was 590 nm.

[Bleeding out of retardation increasing agent]
The bleeding out of the retardation increasing agent was determined according to the following criteria.
A: No bleed out throughout the film.
○: Bleed-out occurrence area is less than 2% in area ratio.
Δ: Bleed-out occurrence area is 2% or more and less than 5% by area ratio.
X: Bleed-out occurrence location is 5% or more by area ratio.
Table 4 shows the evaluation results of the produced cellulose acylate film.

From the results in Table 4, it can be seen that the cellulose acylate films CAF1 to CAF15 of the present invention have high retardation and low bleed out. Moreover, it turns out that the in-plane fluctuation | variation of a retardation becomes small compared with CAF10-13 for the cellulose acylate films CAF1-9 and 14-15 which performed the draw ratio, speed, and time within a specific range. Furthermore, a retardation increasing agent having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm to 10 nm is used. Bleed-out can be more effectively suppressed by mixing with a retardation increasing agent having an isotropic of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less. (CAF9).

[Preparation of polarizing plate]
Example 11-1
[Saponification treatment of cellulose acylate film]
The cellulose acylate film (CAF1) produced in Example 1-1 was immersed in a 1.3 mol / L sodium hydroxide aqueous solution at 55 ° C. for 2 minutes, and then washed in a water bath at room temperature. After neutralizing with 0.05 mol / L sulfuric acid at 0 ° C., it was washed again in a water bath at room temperature and further dried with warm air at 100 ° C. In this manner, the surface of the cellulose acylate film (CAF1) was saponified.

  Further, a commercially available cellulose triacetate film “Fujitac TD80UF” (manufactured by Fuji Photo Film Co., Ltd.) was saponified under the same conditions and used for the following polarizing plate sample preparation.

[Production of polarizer]
Iodine was adsorbed on the stretched PVA film to produce a polarizer, and the cellulose acylate film (CAF1) produced in Example 1-1 was attached to one side of the polarizer using a polyvinyl alcohol-based adhesive. . The transmission axis of the polarizer and the slow axis of the cellulose acylate film were arranged in parallel.

  Further, “Fujitac TD80UF” saponified as described above was attached to the opposite side of the polarizer using a polyvinyl alcohol-based adhesive. In this way, a polarizing plate (P1-1) was produced.

Examples 11-2 to 11-15 and Comparative Examples 11-1 to 11-2
Polarizing plates (P1-2 to 15) and (PR1-1 to 2) were similarly prepared for the cellulose acylate films (CAF2 to 15) and (CAFR1 to 2). Table 5 shows the structure of the obtained polarizing plate.

Example 21-1
[Production and Evaluation of VA Liquid Crystal Display Device 1]
[Production of liquid crystal cell]
1 part by weight of octadecyldimethylammonium chloride (coupling agent) was added to 100 parts by weight of a 3% by weight aqueous solution of polyvinyl alcohol. This was spin-coated on a glass substrate with an ITO electrode, heat-treated at 160 ° C., and then rubbed to form a vertical alignment film. The rubbing treatment was performed in opposite directions on the two glass substrates. Two glass substrates were opposed to each other so that the cell gap (d) was 5 μm. A liquid crystal compound (Δn: 0.08) mainly composed of ester and ethane was injected into the cell gap to produce a vertically aligned liquid crystal cell. The product of Δn and d was 400 nm.

The polarizing plate (P1-7) produced in Example 11-7 was conditioned in advance under the temperature and humidity conditions of 25 ° C. and 60% RH, then wrapped in a moisture-proof bag and left for 3 days. . The bag was a packaging material having a laminated structure of polyethylene terephthalate / aluminum / polyethylene, and the moisture permeability was 1 × 10 ⁻⁵ g / m ² · day or less.

  Under an environment of 25 ° C. and 60% RH, the polarizing plate 7 was taken out and pasted to both surfaces of the produced vertical alignment liquid crystal cell using an adhesive sheet to produce a liquid crystal display device.

  About the produced liquid crystal display screen, when evaluation similar to the method as described in the above [characteristics of polarizing plate] was performed, the liquid crystal display device using the polarizing plate (P1-7) of the present invention has a color viewing angle. Widely preferred.

Example 21-2
[Production and evaluation of VA liquid crystal display device 2]
The liquid crystal display device of FIG. 3 was produced. That is, an upper polarizing plate, a VA mode liquid crystal cell (upper substrate, liquid crystal layer, lower substrate) and a lower polarizing plate were laminated from the observation direction (upper), and a backlight light source was further arranged. In the following example, a commercially available polarizing plate “HLC2-5618” {manufactured by Sanritz Co., Ltd.} is used for the upper polarizing plate, and the polarizing plate of the present invention is used for the lower polarizing plate.

[Production of liquid crystal cell]
The liquid crystal cell has a cell gap of 3.6 μm between substrates and a liquid crystal material having negative dielectric anisotropy (“MLC6608” manufactured by Merck Ltd.) is dropped between the substrates and sealed. Was formed. The retardation of the liquid crystal layer (that is, the product Δn · d of the thickness d (μm) of the liquid crystal layer and the refractive index anisotropy Δn) was set to 300 nm. The liquid crystal material was aligned so as to be vertically aligned.

  A commercially available super high-contrast product “HLC2-5618” {manufactured by Sanritz Co., Ltd.} is applied to the upper polarizing plate 30 of the liquid crystal display device (FIG. 3) using the vertical alignment type liquid crystal cell. In addition, the polarizing plate (P1-1) produced in Example 11-1 was observed by the observer of the VA mode cell 31 through the adhesive so that the cellulose acylate film (CAF1) of the present invention was on the liquid crystal cell side. One sheet was attached to each side and the backlight side. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction.

  The liquid crystal display device using the polarizing plate of the present invention was found to have a wide contrast viewing angle and excellent display quality.

Example 12
[Preparation of polarizing plate]
[Preparation of optical compensation sheet]
(Saponification treatment of cellulose acylate film)
On the cellulose acylate film (CAF9) produced in Example 1-9, a solution having the following composition was applied at 5.2 mL / m ^{2 and} dried at 60 ° C. for 10 seconds. The surface of the film was washed with running water for 10 seconds, and air at 25 ° C. was blown to dry the film surface.

(Saponification composition)
Isopropyl alcohol 818 parts by weight Water 167 parts by weight Propylene glycol 187 parts by weight “EMALEX” manufactured by Nippon Emulsion Co., Ltd. 10 parts by weight Potassium hydroxide 67 parts by weight

(Formation of alignment film)
On a saponified cellulose acylate film (CAF9), a coating solution having the following composition was applied at 24 mL / m ² with a # 14 wire bar coater. Drying was performed with warm air of 60 ° C. for 60 seconds, and further with warm air of 90 ° C. for 150 seconds.
Next, the formed film was rubbed in the direction of 45 ° with the stretching direction of the cellulose acylate film (CAF9) (almost coincident with the slow axis).

(Composition of alignment film coating solution)
Modified polyvinyl alcohol having the following structure 20 parts by mass Water 360 parts by mass Methanol 120 parts by mass Glutaraldehyde (crosslinking agent) 1.0 part by mass

(Formation of optically anisotropic layer)
On the alignment film, 91 parts by mass of a discotic compound having the following structure, 9 parts by mass of ethylene oxide-modified trimethylolpropane triacrylate “V # 360” (manufactured by Osaka Organic Chemical Co., Ltd.), cellulose acetate butyrate “CAB531-1” ( 1.5 parts by mass of Eastman Chemical Co., Ltd., 3 parts by mass of photopolymerization initiator “Irgacure 907” (Ciba Geigy), 1 part by mass of sensitizer “Kayacure DETX” {manufactured by Nippon Kayaku Co., Ltd.} Then, 5.2 mL / m ^{2 of} the coating solution dissolved in 214.2 parts by mass of methyl ethyl ketone was applied with a # 3 wire bar coater. This was affixed to a metal frame and heated in a thermostatic bath at 130 ° C. for 2 minutes to orient the discotic compound. Next, using a 120 W / cm high-pressure mercury lamp at 90 ° C., UV irradiation was performed for 1 minute to polymerize the discotic compound. Then, it stood to cool to room temperature. Thus, an optically anisotropic layer was formed, and an optical compensation sheet (WV2-2) was obtained.

(Saponification treatment of optical compensation sheet)
Saponification was performed in the same manner as Example 11-1.

[Preparation of polarizing plate]
(Production of polarizer)
A polarizer was prepared by adsorbing iodine to a stretched polyvinyl alcohol film. Next, the cellulose acylate film (CAF9) side of the produced optical compensation sheet (WV2-2) was attached to one side of the polarizer using a polyvinyl alcohol-based adhesive. The slow axis of the cellulose acylate film (CAF9) and the transmission axis of the polarizer were arranged in parallel.

  A commercially available cellulose triacetate film “Fujitac TD80UF” (manufactured by Fuji Photo Film Co., Ltd.) was saponified in the same manner as in Example 11-1, and the other side of the polarizer (with an optical compensation sheet was used) using a polyvinyl alcohol adhesive. It was pasted on the side that was not pasted). In this way, an elliptically polarizing plate (P2-1) was produced.

Example 22
[Production of liquid crystal display device]
[Preparation of bend alignment liquid crystal cell]
A polyimide film was provided as an alignment film on a glass substrate with an ITO electrode, and the alignment film was rubbed. The obtained two glass substrates were opposed to each other so that the rubbing directions were parallel to each other, and the cell gap was set to 5.7 μm. A liquid crystal compound “ZLI1132” (manufactured by Merck & Co., Inc.) having Δn of 0.1396 was injected into the cell gap to produce a bend alignment liquid crystal cell.

[Production of liquid crystal display devices]
Two elliptically polarizing plates (P2-1) were attached so as to sandwich the produced bend alignment cell. The optically anisotropic layer of the polarizing plate faced the cell substrate, and the rubbing direction of the liquid crystal cell and the rubbing direction of the optically anisotropic layer facing it were antiparallel.

  It has been found that the liquid crystal display device using the polarizing plate of the present invention has a wide contrast viewing angle and a favorable image with few point defects.

FIG. 1 is an example of a configuration in which the polarizing plate of the present invention and a functional optical film are combined. FIG. 2 is an example of a liquid crystal display device in which the polarizing plate of the present invention is used. FIG. 3 is a schematic view showing an example of the liquid crystal display device of the present invention.

Explanation of symbols

1, 1a, 1b Protective film 2 Polarizer 3 Functional optical film 4 Adhesive layer 5 Polarizing plate 6 Upper polarizing plate 7 Upper polarizing plate absorption axis 8 Upper optical anisotropic layer 9 Upper optical anisotropic layer orientation control direction 10 Liquid crystal Cell upper electrode substrate 11 Upper substrate alignment control direction 12 Liquid crystal molecule 13 Liquid crystal cell lower electrode substrate 14 Lower substrate alignment control direction 15 Lower optical anisotropic layer 16 Lower optical anisotropic layer alignment control direction 17 Lower polarizing plate 18 Lower polarizing plate Absorption axis 30 Upper polarizing plate 31 VA mode liquid crystal cell 32 Lower polarizing plate 33 Cellulose acylate film 34 Polarizer

Claims (12)

At least one type of retardation increase in which the rod-like polarizability anisotropy represented by the following formula (1) is 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and the end-to-end distance is 2 nm or more and 10 nm or less. And at least one kind of agent having a plane polarizability anisotropy represented by the following formula (2) of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less. A cellulose acylate film comprising at least one retardation increasing agent in an amount of 0.1% by mass to 30% by mass with respect to cellulose acylate.
Formula (1): Δα = α _x − (α _y + α _z ) / 2
Formula (2): Δα = (α _x + α _y ) / 2−α _z
(Where α _x is the largest component of eigenvalues obtained after diagonalizing the polarizability tensor; α _y is the second largest eigenvalue obtained after diagonalizing the polarizability tensor. Α _z is the smallest component of the eigenvalues obtained after diagonalizing the polarizability tensor.) Re and Rth at a wavelength of 590 nm are
20 ≦ Re ≦ 200
70 ≦ Rth ≦ 400
1 ≦ Rth / Re ≦ 10
The cellulose acylate film according to claim 1, wherein (Re represents in-plane retardation, and Rth represents retardation in the thickness direction.) A retardation increasing agent having a rod-like polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (1). The cellulose acylate film according to claim 1, which is a compound represented.
General formula (1):
Ar ¹ -L ¹ -XL ² -Ar ²
{In the formula, Ar ¹ and Ar ² each independently represent an aryl group or an aromatic heterocycle. L ¹ and L ² each independently represent —C (═O) O— or —C (═O) NR— (R represents a hydrogen atom or an alkyl group). X represents the following general formula (2) or general formula (3). }
General formula (2):

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represents a hydrogen atom or a substituent.)
General formula (3):

(In the formula, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represents a hydrogen atom or a substituent.) A retardation increasing agent having a rod-shaped polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (4). The cellulose acylate film according to claim 1, which is a compound represented.
General formula (4)

^{(Wherein, R 2-1, R 4-1, R} 5-1 each represent a hydrogen atom or a ^{substituent, R 11-1,} R ^13-1 each represents a hydrogen atom or an alkyl ^{group, L 1- 1} and L ^2-1 each represent a single bond or a divalent linking group, Ar ^1-1 represents an arylene group or an aromatic heterocycle, and Ar ^2-1 represents an aryl group or an aromatic heterocycle. , n-1 represents an integer of 3 or more, n-1 or present ^{L 2-1, Ar 1-1} may each be the same or different. However ^{R 11-1, R 13-1} Are different from each other, and the alkyl group represented by R ^13-1 does not include a hetero atom.) A retardation increasing agent having a rod-shaped polarizability anisotropy of 300 × 10 ⁻²⁵ cm ³ or more and 2000 × 10 ⁻²⁵ cm ³ or less and a molecular end-to-end distance of 2 nm or more and 10 nm or less is represented by the following general formula (5). The cellulose acylate film according to claim 1, which is a compound represented.
General formula (5)

(In the formula, L ¹ and L ² each represent a single bond or a divalent linking group. R ¹ and R ² are each a hydrogen atom or a substituent. R ³ and R ⁴ are respectively Represents a substituent, and n represents an integer of 0 to 4, and when n is 2 or more, a plurality of R ³ may be the same or different, and may be bonded to each other to form a ring. m represents an integer of 0 to 4, and when m is 2 or more, a plurality of R ⁴ may be the same or different from each other, and if possible, may be bonded to each other to form a ring. ¹ represents an integer of ¹ to 5. When X ¹ is 2 or more, a plurality of (R ⁴ ) _m's may be the same or different, and R ⁴¹ represents a hydrogen atom or a substituent. A retardation increasing agent having a plane polarizability anisotropy represented by the mathematical formula (2) of 300 × 10 ⁻²⁵ cm ³ or more and 1500 × 10 ⁻²⁵ cm ³ or less and an end-to-end distance of 2 nm or more and 10 nm or less is The cellulose acylate film according to claim 1 , which is a compound represented by formula (6).
General formula (6):

(Wherein R ²¹ , R ²² and R ²³ each independently represents an alkyl group, an alkenyl group, an aromatic ring group or a heterocyclic group) A method for producing the cellulose acylate film according to any one of claims 1 to 6 , wherein the cellulose acylate film is stretched at a stretch rate of 3% to 200% at a stretch rate of 100% or less per minute. After that, the method for producing a cellulose acylate film is characterized by holding at a draw ratio of 50% to 99% of the maximum draw ratio for 1 second to 120 seconds. The cellulose acylate film according to any one of claims 1-6 prepared by the process of claim 7. In the polarizing plate in which a protective film is bonded to both surfaces of a polarizer, at least one of the protective films is the cellulose acylate film according to any one of claims 1 to 6 and 8. Polarizing plate. The polarizing plate according to claim 9, which has an optically anisotropic layer on at least one surface of the protective film. The polarizing plate according to claim 9 , wherein a retardation film is bonded to at least one surface of the protective film. A liquid crystal display device comprising a liquid crystal cell and two polarizing plates disposed on both sides thereof, wherein at least one polarizing plate is the polarizing plate according to claim 9 .

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