JP4575734B2 - Optical compensation sheet and polarizing plate - Google Patents

Description

The present invention relates to a polarizing plate using the optical compensation sheet and it consists of only one sheet of the cellulose acylate film.

  Among cellulose films, cellulose acetate film is characterized by high optical isotropy (low retardation value) as compared with other polymer films. Therefore, it is common to use a cellulose acetate film for an application requiring optical isotropy, for example, a polarizing plate. On the other hand, optical anisotropy (high retardation value) is required for an optical compensation sheet (phase difference film) such as a liquid crystal display device. Therefore, it is common to use a synthetic polymer film having a high retardation value such as a polycarbonate film or a polysulfone film as the optical compensation sheet.

  As described above, in the technical field of optical materials, when a polymer film requires optical anisotropy (high retardation value), a synthetic polymer film is used and optical isotropy (low retardation value) is used. It is common to use a cellulose acetate film when required.

However, in recent years, a cellulose acetate film having a high retardation value that can be used for applications requiring optical anisotropy has been required, and a technique corresponding to the cellulose acetate film has been proposed (for example, Patent Document 1). In the disclosed invention, in order to achieve a high retardation value with cellulose triacetate, an aromatic compound having at least two aromatic rings, particularly a compound having a 1,3,5-triazine ring, is added and subjected to stretching treatment. .
In general, cellulose triacetate is a polymer material that is difficult to stretch, and it is known that it is difficult to increase the birefringence. However, in Patent Document 1, birefringence is achieved by simultaneously orienting additives in the stretching process. The rate can be increased and a high retardation value is realized. Since this film can also serve as a protective film for a polarizing plate, there is an advantage that an inexpensive and thin liquid crystal display device can be provided.

In recent years, it has become essential to reduce the thickness of a liquid crystal cell in order to reduce the weight of the liquid crystal display device and reduce the manufacturing cost. Therefore, the optical performance required for the optical compensation sheet has a higher Re retardation value and a film having a lower Rth retardation value.
However, as a result of intensive studies by the inventor in the method disclosed in Patent Document 1, the method can achieve both of the above-mentioned Re retardation value and Rth retardation value when setting them individually. It turns out that there is a problem that can not be. In addition to the above-mentioned European patents, there is a patent document disclosing a technique relating to the optical performance of a retardation film for VA, for example, Patent Document 2, but a method for achieving both a desired Re value and an Rth value is not specified. It was.

European Patent Application 0911656A2 JP 2001-116926 A

An object of the present invention is to provide an optical compensation sheet that optically compensates a liquid crystal cell using only a cellulose acylate film.
Another object of the present invention, without increasing the number of components, Ru der to provide a polarizing plate which optimum optical compensation in a liquid crystal display device is added to the polarizing plate.

First, the reason why a high Re / Rth ratio cannot be realized by the method disclosed in Patent Document 1 will be described.
When considering a fixed film thickness, the retardation of the film is determined by the refractive index and the abundance of the material and the orientation state. In the case of the method disclosed in Patent Document 1, it is determined by the triaxial refractive index and orientation state of cellulose triacetate, the refractive index, addition amount, and orientation state of the discotic compound as an additive. Other additives such as plasticizers slightly affect the expression of retardation, but their effects are generally small and will be omitted.
Cellulose triacetate is a material that is generally difficult to stretch, so it is difficult to increase the stretch ratio and it is difficult to achieve a large retardation value. When high retardation is realized using cellulose triacetate as in Patent Document 1, the expressed retardation greatly contributes to the additive.
Since both the Re retardation value and the Rth retardation value are defined by the refractive index in the triaxial direction, the Re / Rth ratio is almost determined by the additive that greatly contributes to the retardation. As a result of examining the Re / Rth ratio with respect to the draw ratio, it was found that the relationship is proportional, and that the Re / Rth ratio increases as the draw ratio increases. The same proportional relationship is obtained when the addition amount is changed, and the Re / Rth ratio increases as the addition amount is increased. It was found that the slope of the Re / Rth ratio with respect to the draw ratio was determined by the additive material, and that the slope of the discotic compound specifically described in Patent Document 1 was small.

The orientation state of cellulose triacetate and additives that determine the retardation value also varies depending on the stretching method. In general, a roll stretching method or a tenter stretching method is known as a method for uniaxial stretching. However, since the former causes shrinkage of the film width and ny decreases (nx-ny), the value tends to increase and Re is easily expressed. . Since the latter is stretched in the width direction while the transport direction is restricted, the value (nx−ny) is unlikely to increase. Therefore, the Re / Rth ratio with respect to the draw ratio is smaller in the latter than in the former.
The tenter stretching method is suitable as a method for producing an optical compensation sheet for a liquid crystal display device because it easily reduces in-plane variations in film thickness and optical performance. When this method is applied to the example disclosed above, the increase amount of the Re / Rth ratio is approximately 0.01 or less per 1% of the draw ratio. When the Re target value is close to the Rth target value and the Re / Rth ratio is about 0.5, a draw ratio of 50% or more is required. It is practically difficult to stably achieve this magnification in a cellulose triacetate film that is difficult to stretch.
In addition, with respect to the addition amount, it was difficult to achieve the target optical performance with an increase in the addition amount that is actually possible.

  In order to increase the amount of Re / Rth increase with respect to the draw ratio when the optimal Re and Rth values as described above are realized by the tenter drawing method, the inventor has disclosed a disk described in Patent Document 1 above. It has been found that the amount of increase in Re / Rth relative to the draw ratio can be increased by using the compound represented by formula (I) and the compound represented by formula (I) as an additive. Based on this finding, the inventors have found that an optical compensation sheet with performance can be produced.

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent, and R ¹ , R ² , R ³ , R ⁴ and R ⁵ each represents an electron donating group, R ⁸ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkynyl group having 2 to 6 carbon atoms. Group, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, cyano Represents a group or a halogen atom.)

An object of the present invention will be more achieved polarizing plate of the optical compensation sheet and the following 22 to 24 below 1-21.
(1) 0.01 to 20 parts by mass of cellulose acylate and at least one compound represented by the following general formula (I) with respect to 100 parts by mass of cellulose acylate and 100 parts by mass of cellulose acylate An optical compensation sheet comprising 0.01 to 20 parts by mass of at least one cyclic compound having at least three substituents .

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent, and R ¹ , R ² , R ³ , R ⁴ and R ⁵ each represents an electron donating group, R ⁸ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkynyl group having 2 to 6 carbon atoms. Group, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, cyano Represents a group or a halogen atom.)
(2) The optical compensation sheet according to item (1), wherein the Re retardation value is 20 to 200 nm and the Rth retardation value is 70 to 400 nm.
(3) The optical compensation sheet according to (1) or (2), wherein the Re retardation value is 20 to 70 nm and the Rth retardation value is 70 to 400 nm.
(4) The ratio of the Re retardation value to the Rth retardation value (Re / Rth ratio) is 0.1 to 0.4, and any one of (1) to (3) Optical compensation sheet.
(5) The optical compensation sheet according to any one of (1) to (4), wherein the optical compensation sheet comprises only one cellulose acylate film having a thickness of 20 μm to 160 μm.
(6) The difference (Re700-Re400) between the Re retardation value at 700 nm (Re700) and the Re retardation value at 400 nm (Re400) is -25 nm to 10 nm, (1) to (5 The optical compensation sheet according to any one of items 1).
(7) The difference between the Rth retardation value at 700 nm (Rth700) and the Rth retardation value at 400 nm (Rth400) (Rth700−Rth400) is −50 nm to 20 nm, (1) to (6) The optical compensation sheet according to any one of items 1).
(8) Re retardation value measured in an environment of 25 ° C. and 10% RH, Rth retardation value, and Re retardation value measured in an environment of 25 ° C. and 80% RH, and Rth retardation value are within 25 nm, The optical compensation sheet according to any one of (1) to (7), which is within 70 nm.
(9) The optical compensation according to any one of (1) to (8), wherein the moisture permeability at 25 ° C. and 90% RH is 20 g / m ² · 24 hr to 250 g / m ² · 24 hr. Sheet.
(10) The optical compensation sheet according to any one of (1) to (9), wherein a dimensional change under a drying condition at 90 ° C. is within −0.15%.
(11) The optical compensation sheet according to any one of (1) to (10), wherein a dimensional change at 60 ° C. and 90% RH is within −0.15%.
(12) The optical compensation sheet according to any one of (1) to (11), comprising a cellulose acetate film having a surface energy of 55 to 75 mN / m.
(13) Any one of (1) to (12), wherein a decrease in the degree of polarization after aging for 500 hours in an atmosphere of 60 ° C. and 95% RH when used as a polarizing plate protective film is within 3%. The optical compensation sheet according to item.
(14) The optical compensation sheet according to any one of (1) to (13), comprising a cellulose acylate film stretched at a stretch ratio of 3 to 100%.
(15) The cellulose acylate is a cellulose acetate having an acetylation degree of 59.0 to 61.5%, and a Re / Rth change amount per 1% of draw ratio is 0.01 to 0.1. The optical compensation sheet according to any one of (1) to (14).
(16) The film is stretched in a direction perpendicular to the longitudinal direction while being conveyed in the longitudinal direction, the residual solvent amount of the cellulose acylate film at the start of stretching is in a state of 2% to 50%, and the slow axis of the film is The optical compensation sheet according to any one of (1) to (15), wherein the optical compensation sheet is in a direction perpendicular to the longitudinal direction of the film.
(17) The cellulose acylate film comprises a cellulose acylate in which a hydroxyl group of cellulose is substituted with an acetyl group and an acyl group having 3 to 22 carbon atoms, and the substitution degree A and carbon of the acetyl group of the cellulose acylate The optical compensation sheet according to any one of (1) to (16), wherein the substitution degree B of the acyl group having 3 to 22 atoms satisfies the following formulas (VI) and (VII):
Formula (VI): 2.0 ≦ A + B ≦ 3.0
Formula (VII): 0 <B
(18) The optical compensation sheet according to item (17), wherein the acyl group having 3 to 22 carbon atoms is a butanoyl group or a propionyl group.
(19) A film comprising cellulose acylate obtained by substituting a hydroxyl group of a glucose unit constituting cellulose with an acyl group having 2 or more carbon atoms, wherein the hydroxyl group at the 2-position of the glucose unit constituting cellulose is Cellulose satisfying the following formulas (XII) and (XIII) when the substitution degree by the acyl group is DS2, the substitution degree by the acyl group of the hydroxyl group at the 3-position is DS3, and the substitution degree by the acyl group of the hydroxyl group at the 6-position is DS6 The optical compensation sheet according to any one of (1) to (18), which is an acylate film.
Formula (XII): 2.0 ≦ DS2 + DS3 + DS6 ≦ 3.0
Formula (XIII): DS6 / (DS2 + DS3 + DS6) ≧ 0.320
(20) The optical compensation sheet according to any one of ( 1) to (16), wherein the cellulose acylate is cellulose acetate .
(21) The optical compensation sheet according to item (1), wherein the cyclic compound having at least three substituents is a compound represented by the general formula (II).

(Wherein, X ¹ is a single bond, -NR ⁴ -, - O-or -S- were tables,; X ² represents a single bond, -NR ⁵ -, - O-or -S- were table ,; X ³ represents a single bond, -NR ⁶ -, - Represents O- or -S-,; R ^1, R ² and R ³ are each independently an alkyl group, an alkenyl group, an aryl group or a heterocyclic the ring was tables; and, R ^4, R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group, an alkenyl group, table to an aryl group or a heterocyclic group).
(22) A polarizing plate comprising a polarizing film and two transparent protective films disposed on both sides thereof, wherein at least one of the transparent protective films is the optical element according to any one of (1) to (21) A polarizing plate, which is a compensation sheet.
(23) The transparent protective film opposite to the optical compensation sheet is provided with an antireflection layer having a specular reflectance of 2.5% or less comprising at least a light scattering layer and a low refractive index layer (22) The polarizing plate as described in a term.
(24) An antireflection layer having a specular reflectance of 0.5% or less, in which at least a middle refractive index layer, a high refractive index layer, and a low refractive index layer are laminated in this order on the transparent protective film on the side opposite to the optical compensation sheet The polarizing plate according to item (22) or (23), wherein

The optical compensation sheet of the present invention can optically compensate a liquid crystal cell only with a cellulose acetate film.
By using the cellulose acetate film in combination with an aromatic compound having at least two aromatic rings (specifically, a compound having a 1,3,5-triazine ring) and a compound represented by the general formula (I), A cellulose acetate film having an Re retardation value of 20 to 200 nm, an Rth retardation value of 70 to 400 nm, and an Re / Rth ratio of 0.1 to 0.8 is obtained. This cellulose acetate film has sufficient optical anisotropy to optically compensate the liquid crystal cell. Accordingly, an optical compensation sheet consisting of only one cellulose acetate film can be obtained.
The protective film of the polarizing plate is generally made of a cellulose acetate film. When the cellulose acetate film is used as one protective film of the polarizing plate, an optical compensation function can be added to the polarizing plate without increasing the number of components of the polarizing plate.
The optical compensation sheet consisting only of the cellulose acetate film and the polarizing plate using the cellulose acetate film as a protective film can be used particularly advantageously for VA mode and OCB mode liquid crystal display devices.

[Film retardation]
In this specification, Re (λ) and Rth (λ) respectively represent in-plane retardation and retardation in the thickness direction at a wavelength λ. 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 the light of wavelength λnm from the direction inclined by + 40 ° with respect to the normal direction of the film, with Re (λ) and the in-plane slow axis (determined by KOBRA 21ADH) as the tilt axis (rotary axis). And a retardation value measured by making light of wavelength λ nm incident from a direction inclined by −40 ° with respect to the film normal direction with the in-plane slow axis as the tilt axis (rotation axis). KOBRA 21ADH is calculated based on retardation values measured in three directions in total. Here, as the assumed value of the average refractive index, values in the polymer handbook (John Wiley & Sons, Inc.) and catalogs of various optical films can be used. The average refractive index of cellulose acylate is 1.48. The KOBRA 21ADH calculates nx, ny, and nz by inputting the assumed value of the average refractive index and the film thickness.

In the present invention, preferably, the Re retardation value of the cellulose acylate film is adjusted to 20 to 200 nm, and the Rth retardation value is adjusted to 70 to 400 nm. In the present invention, the Re / Rth ratio is preferably adjusted to 0.1 to 0.8. More preferably, the Re retardation value is adjusted to 20 to 70 nm, the Rth retardation value is adjusted to 90 to 300 nm, and the Re / Rth ratio is adjusted to 0.25 to 0.8. These adjustments can be made according to the type of rod-shaped compound, the amount added, the type of disk-shaped compound, the amount added, and the draw ratio.
In the present invention, the amount of change in Re / Rth per 1% stretch ratio can be 0.01 to 0.1. Here, the amount of change in Re / Rth per 1% of the draw ratio can be determined from the slope when the Re / Rth ratios for the draw ratios of at least three points with a draw ratio of 5% or more are linearly approximated.

[Cellulose acylate film]
Next, the cellulose acylate used in the present invention will be described in detail. In the present invention, two or more different cellulose acylates may be mixed and used.
The cellulose acylate is preferably a mixed fatty acid ester of cellulose obtained by substituting the hydroxyl group of cellulose with an acetyl group and an acyl group having 3 to 22 carbon atoms, and has a degree of substitution with the hydroxyl group of cellulose. It is a cellulose acylate satisfying the following formulas (VI) and (VII).
Formula (VI): 2.0 ≦ A + B ≦ 3.0
Formula (VII): 0 <B
Here, A and B represent the substitution degree of the acyl group substituted with the hydroxyl group of cellulose, A is the substitution degree of the acetyl group, and B is the substitution degree of the acyl group having 3 to 22 carbon atoms. .
Glucose units having β-1,4 bonds constituting cellulose have free hydroxyl groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer obtained by esterifying some or all of these hydroxyl groups with acyl groups. The degree of acyl substitution means the proportion of cellulose esterified at each of the 2-position, 3-position and 6-position (100% esterification has a degree of substitution of 1).
In the present invention, the total substitution degree (A + B) of hydroxyl groups A and B is 2.0 to 3.0, preferably 2.2 to 2.9, as shown in the above formula (VI). And particularly preferably 2.40 to 2.85. Further, the substitution degree of B is preferably larger than 0, more preferably 0.6 or more, as shown in the above formula (VII).
When A + B is less than 2.0, the hydrophilicity becomes strong and it is easy to be affected by environmental humidity.
Further, 28% or more of B is preferably a 6-position hydroxyl group substituent, more preferably 30% or more is a 6-position hydroxyl group substituent, more preferably 31% or more, and particularly preferably 32% or more. A substituent at the 6-position hydroxyl group is preferred.
Furthermore, the sum of the substitution degrees of A and B at the 6-position of cellulose acylate is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more. With these cellulose acylate films, a solution for preparing a film having preferable solubility and filterability can be produced, and a good solution can be produced even in a non-chlorine organic solvent. Furthermore, it becomes possible to produce a solution having a low viscosity and good filterability.

Further, when the cellulose acylate film is a protective film disposed on the liquid crystal cell side of the polarizing plate, the substitution degree of the 2-position hydroxyl group of the glucose unit constituting the cellulose with an acyl group is DS2, and the acyl group of the 3-position hydroxyl group is It is preferable that the following formulas (XII) and (XIII) are satisfied, where DS is the substitution degree by DS3 and DS6 is the substitution degree by the acyl group of the hydroxyl group at the 6-position.
Formula (XII): 2.0 ≦ DS2 + DS3 + DS6 ≦ 3.0
Formula (XIII): DS6 / (DS2 + DS3 + DS6) ≧ 0.315
By satisfying the above formulas (XII) and (XIII), it is easy to adjust the optical performance within a preferable range, which is preferable.
DS2 + DS3 + DS6 may be referred to as acetyl substitution degree, and DS6 / (DS2 + DS3 + DS6) may be referred to as 6-position substitution degree.

  The acyl group having 3 or more carbon atoms may be an aliphatic group or an aromatic hydrocarbon group, and is not particularly limited. These are, for example, cellulose alkylcarbonyl esters, alkenylcarbonyl esters, aromatic carbonyl esters, aromatic alkylcarbonyl esters, and the like, each of which may further have a substituted group. Preferred acyl groups having 3 or more carbon atoms include propionyl, butanoyl, keptanoyl, hexanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, iso-butanoyl, t-butanoyl, cyclohexanecarbonyl Oleoyl, benzoyl, naphthylcarbonyl, cinnamoyl group and the like. Among these, propionyl, butanoyl, dodecanoyl, octadecanoyl, t-butanoyl, oleoyl, benzoyl, naphthylcarbonyl, cinnamoyl group and the like are preferable. Particularly preferred are propionyl and butanoyl groups. In the case of a propionyl group, the substitution degree B is preferably 1.3 or more.

  Specific examples of the mixed fatty acid cellulose acylate include cellulose acetate propionate and cellulose acetate butyrate.

(Method for synthesizing cellulose acylate)
The basic principle of the cellulose acylate synthesis method is described in Mita et al., Wood Chemistry pages 180-190 (Kyoritsu Shuppan, 1968). A typical synthesis method is a liquid phase acetylation method using a carboxylic acid anhydride-acetic acid-sulfuric acid catalyst.
In order to obtain the cellulose acylate, specifically, a cellulose raw material such as cotton linter or wood pulp is pretreated with an appropriate amount of acetic acid, and then esterified by introducing it into a pre-cooled carboxylated mixed solution. Synthesize the rate (total of acyl substitutions at the 2nd, 3rd and 6th positions is approximately 3.00). The carboxylated mixed solution generally contains acetic acid as a solvent, carboxylic anhydride as an esterifying agent, and sulfuric acid as a catalyst. The carboxylic anhydride is usually used in a stoichiometric excess over the sum of the cellulose that reacts with it and the water present in the system. After completion of the esterification reaction, a neutralizing agent (for example, calcium, magnesium, iron, aluminum or zinc) is used for hydrolysis of excess carboxylic anhydride remaining in the system and neutralization of a part of the esterification catalyst. Of carbonate, acetate or oxide). Next, the obtained complete cellulose acylate is saponified and aged by maintaining it at 50 to 90 ° C. in the presence of a small amount of an acetylation reaction catalyst (generally, remaining sulfuric acid) to obtain the desired degree of acyl substitution and polymerization. The cellulose acylate having a degree is changed. When the desired cellulose acylate is obtained, the catalyst remaining in the system is completely neutralized with the neutralizing agent as described above, or in water or dilute sulfuric acid without neutralization. The cellulose acylate solution is added (or water or dilute sulfuric acid is added to the cellulose acylate solution), the cellulose acylate is separated, washed and stabilized, and the like. Can be obtained.

In the cellulose acylate film, it is preferable that the polymer component constituting the film is substantially composed of the specific cellulose acylate. “Substantially” means 55% by mass or more (preferably 70% by mass or more, more preferably 80% by mass or more) of the polymer component.
The cellulose acylate is preferably used in the form of particles. 90% by mass or more of the particles to be used preferably have a particle diameter of 0.5 to 5 mm. Moreover, it is preferable that 50 mass% or more of the particle | grains to be used have a particle diameter of 1-4 mm. The cellulose acylate particles preferably have a shape as close to a sphere as possible.
The degree of polymerization of the cellulose acylate preferably used in the present invention is a viscosity average degree of polymerization, preferably 200 to 700, more preferably 250 to 550, still more preferably 250 to 400, and particularly preferably 250 to 350. . The average degree of polymerization can be measured by Uda et al.'S intrinsic viscosity method (Kazuo Uda, Hideo Saito, Journal of Textile Society, Vol. 18, No. 1, pages 105-120, 1962). Further details are described in JP-A-9-95538.

When the low molecular component is removed, the average molecular weight (degree of polymerization) is increased, but the viscosity is lower than that of ordinary cellulose acylate. . Cellulose acylate having a small amount of low molecular components can be obtained by removing low molecular components from cellulose acylate synthesized by a usual method. The removal of the low molecular component can be carried out by washing the cellulose acylate with an appropriate organic solvent. In addition, when manufacturing a cellulose acylate with few low molecular components, it is preferable to adjust the sulfuric acid catalyst amount in an acetylation reaction to 0.5-25 mass parts with respect to 100 mass parts of cellulose acylates. When the amount of the sulfuric acid catalyst is in the above range, cellulose acylate that is preferable in terms of molecular weight distribution (uniform molecular weight distribution) can be synthesized. When used in the production of cellulose acylate, the water content is preferably 2% by mass or less, more preferably 1% by mass or less, and particularly 0.7% by mass or less. In general, cellulose acylate contains water and is known to have a water content of 2.5 to 5% by mass. In order to obtain the moisture content of the cellulose acylate in the present invention, it is necessary to dry, and the method is not particularly limited as long as the desired moisture content is obtained.
The cellulose acylate raw material cotton and the synthesis method thereof are disclosed in JIII Journal of Technical Disclosure No. 2001-1745 (issued March 15, 2001, Invention Association) p. Raw material cotton and synthetic methods described in detail in 7-12 can be employed.

  The cellulose acylate film according to the present invention can be obtained by forming a film using a solution obtained by dissolving the specific cellulose acylate and, if necessary, an additive in an organic solvent.

[Retardation control agent]
In the present invention, the compound represented by the general formula (I) and the cyclic compound having at least three substituents are used in combination and added to the cellulose ester film. Both the cyclic compound having at least three substituents and the compound represented by the general formula (I) can function as a retardation increasing agent for a cellulose ester film.
Here, the cyclic compound having at least three substituents is preferably an aromatic compound having at least two aromatic rings, and preferably a compound having a 1,3,5-triazine ring represented by the general formula (II). Can be used. Alternatively, a compound having a porphyrin skeleton can be preferably used. In particular, it is preferable to use the compounds described in JP-A No. 2001-166144.

Below, it demonstrates in detail regarding the compound represented by General formula (1).
General formula (1)

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a substituent, and R ¹ , R ² , R ³ , R ⁴ and R ⁵ each represents an electron donating group, R ⁸ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, or an aryl having 6 to 12 carbon atoms. A group, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom.

In general formula (1), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a substituent, and the substituent will be described later. The substituent T can be applied.
At least one of R ¹ , R ² , R ³ , R ⁴ and R ⁵ represents an electron donating group. Preferably, one of R ¹ , R ³ or R ⁵ is an electron donating group, and R ³ is more preferably an electron donating group.
An electron donating group is one having a Hammet's σ _p value of O or less, Chem. Rev. 91, 165 (1991). Those having Hammet's σ _p value of O or less can be preferably applied, and those having −0.85 to 0 are more preferably used. Examples thereof include an alkyl group, an alkoxy group, an amino group, and a hydroxyl group.
The electron donating group is preferably an alkyl group or an alkoxy group, more 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, particularly preferably carbon). 1 to 4).

R ¹ is preferably a hydrogen atom or an electron donating group, more preferably an alkyl group, an alkoxy group, an amino group, or a hydroxyl group, and still more preferably an alkyl group having 1 to 4 carbon atoms or a carbon number 1 to 12 Particularly 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). Most preferred is a methoxy group.

R ² 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 a carbon number). 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, even more preferably having a carbon number of 1-6, particularly preferably having a carbon number of 1 4). Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.

R ³ 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, still more preferably an alkyl group or an alkoxy group, particularly 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). Most preferred are n-propoxy group, ethoxy group and methoxy group.

R ⁴ 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 an alkyl group having 1 to 4 carbon atoms. And 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). 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, a methyl group, or a methoxy group.

R ⁵ 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 a carbon number). 1-4, more preferably a methyl group.), An alkoxy group (preferably having 1-12 carbon atoms, more preferably 1-8 carbon atoms, still more preferably 1-6 carbon atoms, and most preferably 1-4 carbon atoms). It is. Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.

R ⁶ , R ⁷ , R ⁹ and R ¹⁰ are preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or a halogen atom, more preferably a hydrogen atom or a halogen atom ( A chlorine atom, a bromine atom, an iodine atom, etc.), and more preferably a hydrogen atom.

R ⁸ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy having 6 to 12 carbon atoms. Group, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom, which may have a substituent if possible. The group T can be applied.
R ⁸ is preferably an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 2 to 12 carbon atoms. And more preferably an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms, more preferably an alkoxy group having 1 to 12 carbon atoms (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms), and particularly preferably a methoxy group, an ethoxy group, and n. -A propoxy group, an iso-propoxy group, and an n-butoxy group.

Of the general formula (1), the following general formula (1-A) is more preferable.
General formula (1-A)

(In the formula, R ¹¹ represents an alkyl group. R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent. R ⁸ Is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, Represents an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom.)
In general formula (1-A), R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ have the same meanings as those in general formula (1), and The preferable range is also the same.

In General Formula (1-A), R ¹¹ represents an alkyl group having 1 to 12 carbon atoms, and the alkyl group represented by R ¹¹ may be linear or branched, and further has a substituent. However, it is preferably 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, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group and the like.

Of the general formula (1), the following general formula (1-B) is more preferable.
Formula (1-B)

(In the formula, R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent. R ¹¹ is an alkyl having 1 to 12 carbon atoms. X represents an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. A group, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom.)

In general formula (1-B), R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ have the same meanings as those in general formula (1), and preferred ranges are also the same. It is.
In General Formula (1-B), R ¹¹ has the same meaning as those in General Formula (1-A), and the preferred range is also the same.

In general formula (1-B), X is an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and 6 carbon atoms. Represents an aryloxy group having 12 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom.
When all of R ¹ , R ² , R ⁴ and R ⁵ are hydrogen atoms, X is preferably an alkyl group, alkynyl group, aryl group, alkoxy group or aryloxy group, more preferably an aryl group or alkoxy group. And an aryloxy group, more 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 preferably a methoxy group, a methoxy group, an n-propoxy group, an iso-propoxy group or an n-butoxy group.

When at least one of R ¹ , R ² , R ⁴ and R ⁵ is a substituent, X is preferably an alkynyl group, aryl group, alkoxycarbonyl group or cyano group, more preferably an aryl group (preferably 6 to 12 carbon atoms), a cyano group, and an alkoxycarbonyl group (preferably 2 to 12 carbon atoms), more preferably an aryl group (preferably an aryl group having 6 to 12 carbon atoms, more preferably a phenyl group, p-cyanophenyl group and p-methoxyphenyl group), an alkoxycarbonyl group (preferably having 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, still more preferably 2 to 4 carbon atoms, particularly preferably methoxycarbonyl, Ethoxycarbonyl, n-propoxycarbonyl), cyano group, particularly preferably phenyl group, methoxycarbony. Group, an ethoxycarbonyl group, n- propoxycarbonyl group, a cyano group.

Of the general formula (1), the following general formula (1-C) is more preferable.
Formula (1-C)

(In the formula, R ¹ , R ² , R ⁴ , R ⁵ , R ¹¹ and X have the same meanings as those in the general formula (1-B), and preferred ranges are also the same.)

Among the compounds represented by the general formula (1), a compound represented by the following general formula (1-D) is preferable.
Formula (1-D)

(In the formula, R ² , R ⁴ and R ⁵ have the same meanings as those in formula (1-C) and preferred ranges are also the same. R ²¹ and R ²² each independently has 1 to 4 carbon atoms. X ¹ is an aryl group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, or a cyano group.

R ²¹ represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more preferably an ethyl group or a methyl group.
R ²² represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably an ethyl group or a methyl group, and still more preferably a methyl group.

X ¹ is an aryl group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, or a cyano group, preferably an aryl group having 6 to 10 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, or a cyano group. More preferably a phenyl group, a p-cyanophenyl group, a p-methoxyphenyl group, a methoxycarbonyl, an ethoxycarbonyl, an n-propoxycarbonyl, a cyano group, and still more preferably a phenyl group, a methoxycarbonyl group, an ethoxycarbonyl group, n-propoxycarbonyl group, cyano group.

Of the general formula (1), the following general formula (1-E) is most preferable.
Formula (1-E)

(Wherein R ² , R ⁴ and R ⁵ have the same meanings as those in formula (1-D) and preferred ranges are also the same, but one of them is a group represented by —OR ¹³ ( R ¹³ is an alkyl group having 1 to 4 carbon atoms.) R ²¹ , R ²² and X ¹ have the same meanings as those in formula (1-D), and preferred ranges are also the same.)

In general formula (1-E), R ² , R ⁴ and R ⁵ have the same meanings as those in general formula (1-D), and preferred ranges are also the same, but one of them is represented by —OR ^13. (R ¹³ is an alkyl group having 1 to 4 carbon atoms), preferably R ⁴ and R ⁵ are groups represented by —OR ¹³ , more preferably R ⁴ is —OR ¹³ . It is a group represented.
R ¹³ represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably an ethyl group or a methyl 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, and particularly preferably 1 to 8 carbon atoms such as methyl, ethyl, iso-propyl, tert-butyl, and 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, and particularly preferably carbon number). 2 to 8, for example, vinyl, allyl, 2-butenyl, 3-pentenyl, etc.), an alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably carbon number). 2-8, for example, propargyl, 3-pentynyl, etc.), aryl groups (preferably having 6-30 carbon atoms) More preferably, it has 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include phenyl, p-methylphenyl, naphthyl and the like, and a substituted or unsubstituted amino group (preferably having 0 to 0 carbon atoms). 20, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms, and examples thereof include amino, methylamino, dimethylamino, diethylamino, dibenzylamino and the like.

An alkoxy group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as methoxy, ethoxy, butoxy, etc.), an aryloxy group (preferably C6-C20, More preferably C6-C16, Most preferably C6-C12, for example, phenyloxy, 2-naphthyloxy, etc.), acyl groups (preferably C1-C1) 20, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as acetyl, benzoyl, formyl, pivaloyl, etc.), an alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, and more). Preferably it has 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonyl or ethoxycarbonyl. An aryloxycarbonyl group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms, such as phenyloxycarbonyl). An acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 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 Has 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, and examples thereof include methoxycarbonylamino and the like, and an aryloxycarbonylamino group (preferably 7 to 7 carbon atoms). 20, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonylamino, and the like, 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 Benzenesulfonylamino, etc.), sulfamoyl groups (preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms. Sulfamoyl, phenylsulfamoyl, etc.),

A carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include carbamoyl, methylcarbamoyl, diethylcarbamoyl, phenylcarbamoyl and the like), alkylthio. A 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 6 to 6 carbon atoms). 20, More preferably, it is C6-C16, Most preferably, it is C6-C12, for example, phenylthio etc. are mentioned, A sulfonyl group (Preferably C1-C20, More preferably C1-C16 , Particularly preferably having 1 to 12 carbon atoms, such as mesyl and tosyl).

Sulfinyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as methanesulfinyl, benzenesulfinyl, etc.), ureido group (preferably carbon 1 to 20, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as ureido, methylureido, phenylureido, etc.), phosphoric acid amide group (preferably having 1 carbon atom) -20, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as diethyl phosphate amide and phenyl phosphate 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 a carbon number of 1-30, more preferably 1-12. Examples of heteroatoms include nitrogen, oxygen, sulfur, For example, imidazolyl, pyridyl, quinolyl, furyl, piperidyl, morpholino, benzoxazolyl, benzimidazolyl, benzthiazolyl, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 carbon atoms). To 30 and particularly preferably 3 to 24 carbon atoms, 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 compound represented by the general formula (1) of the present invention can be synthesized by a general ester reaction of a substituted benzoic acid and a phenol derivative, and any reaction may be used as long as it is an ester bond forming reaction. Examples thereof include a method of converting a substituted benzoic acid to an acid halide and then condensing with phenol, a method of dehydrating the substituted benzoic acid and a phenol derivative using a condensing agent or a catalyst, and the like.
In view of the production process and the like, a method in which the substituted benzoic acid is functionally converted to an acid halide and then condensed with phenol is preferable.

  Reaction solvents include hydrocarbon solvents (preferably toluene and xylene), ether solvents (preferably dimethyl ether, tetrahydrofuran, dioxane, etc.), ketone solvents, ester solvents, acetonitrile, dimethylformamide, dimethyl Acetamide or the like can be used. 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 and the like).

  The compound represented by formula (I) and the cyclic compound having at least three substituents are each used in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of cellulose acetate. The compound represented by the general formula (I) and the cyclic compound having at least three substituents are preferably used in the range of 0.05 to 15 parts by mass with respect to 100 parts by mass of cellulose acetate. It is more preferable to use in the range of 10 to 10 parts by mass. Two or more compounds may be used in combination for the compound represented by the general formula (I) and the cyclic compound having at least three substituents.

As specified in Japanese Patent Application Laid-Open No. 2001-166144, generally, a discotic compound has a higher retardation increasing effect than a rod-shaped compound, and increases the retardation of a cellulose ester film even with a relatively small amount of use. be able to. However, since not only the Re retardation value but also the Rth retardation value increases, only the discotic compound is used, and the object of the present invention is to have a high Re retardation value and a low Rth retardation value. It was difficult to produce a cellulose ester film.
Further, when a rod-like compound is used, a cellulose acetate film having a large Re / Rth ratio can be produced. To achieve the high Re retardation value which is the object of the present invention using only a rod-like compound, the rod-like compound is used. Need to be added in large quantities. Increasing the amount added is not only disadvantageous in terms of cost, but also tends to cause precipitation (bleed out) on the surface of the cellulose ester film, which is not preferable in terms of production suitability. Therefore, it was also difficult to produce a cellulose ester film having optical performance, which is an object of the present invention, using only a rod-like compound.

  As a result of intensive studies by the present inventors, by adding a discotic compound and a rod-shaped compound (compound represented by the general formula (I)) in combination, not only a simple addition effect but also a more preferable optical performance than expected. It was found that (high Re retardation value, low Rth retardation value) can be achieved.

[Manufacture of cellulose acetate film]
It is preferable to produce a cellulose acylate film by a solvent casting 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.
The ether, ketone and ester 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 may be within the specified range of the compound 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 halogenated hydrocarbon hydrogen atoms substituted with halogen is preferably 25 to 75 mol%, more preferably 30 to 70 mol%, and more preferably 35 to 65 mol%. More preferably, it is 40 to 60 mol%, and most preferably. Methylene chloride is a representative halogenated hydrocarbon.
Two or more organic solvents may be mixed and used.

A cellulose acylate solution can be prepared by a general method. The general method means that the treatment is performed at a temperature of 0 ° C. or higher (room temperature or high temperature). The solution can be prepared 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 that it is contained in an amount of 10 to 40% by mass in the resulting solution. 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., 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 needs to be configured so that it can be stirred. 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.
It is preferable to provide a stirring blade inside the container and stir using this. 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 the 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 acetate 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 acetate 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 acetate 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 at 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.). When cooled in this way, the mixture of cellulose acylate and organic solvent solidifies.
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 until the final cooling temperature is reached.

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 acetate is dissolved 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, if 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 differential scanning calorimetry (DSC), a 20% by mass solution of cellulose acylate (acetylation degree: 60.9%, viscosity average polymerization degree: 299) dissolved in methyl acetate by the cooling dissolution method is There is a quasi-phase transition point between a sol state and a gel state in the vicinity of 33 ° C., and a uniform gel state is obtained below this temperature. Therefore, this solution needs to be stored at a temperature equal to or higher than the pseudo phase transition temperature, preferably about the gel phase transition temperature plus about 10 ° C. However, this pseudo phase transition temperature varies depending on the degree of acetylation of cellulose acylate, the degree of viscosity average polymerization, the solution concentration, and the organic solvent used.
The degree of acetylation means the amount of bound acetic acid per unit weight of cellulose. The degree of acetylation follows the measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method for cellulose acetate and the like).

From the prepared cellulose acylate solution (dope), a cellulose acylate film is produced by a solvent cast method.
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. As for casting and drying methods in the solvent casting method, U.S. Pat. No. 736892, JP-B Nos. 45-4554, 49-5614, JP-A-60-176834, No. 60-203430, and No. 62-1115035.

  The dope is preferably cast on a drum or band having a surface temperature of 10 ° C. or less. After casting, it is preferable to dry it by applying air for 2 seconds or more. 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 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.

  A plasticizer can be added to the cellulose acylate film in order to improve mechanical properties or increase the drying speed. As the plasticizer, phosphoric acid ester or carboxylic acid ester is used. Examples of phosphate esters include triphenyl phosphate (TPP) and tricresyl phosphate (TCP).

Representative examples of the carboxylic acid ester include phthalic acid esters and citric acid esters. Examples of phthalic acid esters include dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diphenyl phthalate (DPP) and diethylhexyl phthalate (DEHP). Examples of citrate esters include triethyl O-acetylcitrate (OACTE) and tributyl O-acetylcitrate (OACTB). Examples of other carboxylic acid esters include butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and various trimellitic acid esters. Phthalate plasticizers (DMP, DEP, DBP, DOP, DPP, DEHP) are preferably used. DEP and DPP are particularly preferred.
The addition amount of the plasticizer is preferably 0.1 to 25% by mass, more preferably 1 to 20% by mass, and most preferably 3 to 15% by mass of the amount of the cellulose ester.

  A degradation inhibitor (eg, antioxidant, peroxide decomposer, radical inhibitor, metal deactivator, acid scavenger, amine) may be added to the cellulose acetate 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 amount of the deterioration inhibitor added is 0.01 to 1 of the solution (dope) to be prepared from the viewpoint that the effect of the addition of the deterioration inhibitor is manifested and the bleeding out of the deterioration inhibitor to the film surface is suppressed. The content is preferably mass%, more preferably 0.01 to 0.2 mass%. Examples of particularly preferred deterioration inhibitors include butylated hydroxytoluene (BHT) and tribenzylamine (TBA).

[Stretching treatment of cellulose acylate film]
The retardation of the cellulose acetate film can be adjusted by a stretching process. The draw ratio is preferably 3 to 100%.
As the stretching method, an existing method can be used without departing from the scope of the claims, but tenter stretching is particularly preferably used from the viewpoint of in-plane uniformity. The cellulose acylate film of the present invention preferably has a width of at least 100 cm, the variation in the Re value of the entire width is preferably ± 5 nm, and more preferably ± 3 nm. Further, the variation of the Rth value is preferably ± 10 nm, and more preferably ± 5 nm. Further, it is preferable that the variation in the Re value and the Rth value in the length direction is also within the range of the variation in the width direction.

In addition, the stretching process may be performed in the middle of the film forming process, or the raw film that has been formed and wound may be stretched. In the former case, stretching may be performed in a state including the residual solvent amount, and the residual solvent amount at the start of stretching is preferably 2 to 50%. The amount of residual solvent at the start of stretching is the amount of residual solvent when starting to grip both ends of the web (raw dry dope) with clips in the case of tenter stretching, and starts stretching at 5 to 50%. It is more preferable to start stretching at 10 to 45%. The residual solvent amount is calculated by the following formula.
(Residual solvent amount) =
100 × {(Amount of solvent in web) / (Total amount of web)}
At this time, it is preferable to stretch the film in the direction perpendicular to the longitudinal direction while conveying the film in the longitudinal direction so that the slow axis of the film is orthogonal to the longitudinal direction of the film.
The stretching temperature can be selected appropriately depending on the amount of residual solvent and film thickness during stretching.

When stretching in a state containing a residual solvent, it is preferable to dry after stretching. The drying method can be performed according to the method described in the film production.
The thickness of the cellulose acetate film after stretching is preferably 20 to 160 μm, more preferably 60 to 110 μm, and most preferably 80 to 110 μm. This film thickness corresponds to the film thickness of the optical compensation sheet of the present invention.

[Wavelength dispersion of cellulose acylate film]
Examples of the performance required for the optical compensation sheet include a wavelength dispersion shape having an Re retardation value and an Rth retardation value. The optical compensation sheet acts as a negative retarder, and compensates for the liquid crystal that is a positive retarder. To compensate for polarization in the entire visible wavelength range, the Rth retardation value of the optical compensation sheet is the wavelength dispersion shape of the liquid crystal. It is necessary to be similar. At present, it is known that most of the wavelength dispersion shape of the liquid crystal sealed in the liquid crystal cell is forward dispersion. Therefore, the Re retardation value and Rth retardation value wavelength dispersion shape of the optical compensation sheet are also forward dispersion shapes. That is, the difference (Re700−Re400) between the Re retardation value at 700 nm (Re700) and the Re retardation value at 400 nm (Re400) is preferably −25 nm to 10 nm, and −25 nm to 5 nm. More preferably it is. The difference between the Rth retardation value at 700 nm (Rth700) and the Rth retardation value at 400 nm (Rth400) (Rth700-Rth400) is preferably -50 nm to 20 nm, and further Rth700-Rth400 is -50 nm. It is particularly preferable that the thickness is 10 nm.

  Re700-Re400 and Rth700-Rth400 were obtained by measuring Rth retardation values at a wavelength of 700 nm and a wavelength of 400 nm using an ellipsometer (M-150, manufactured by JASCO Corporation) for the produced cellulose acetate film.

[Humidity dependence of Re retardation value and Rth retardation value]
It is desirable that the Re retardation value and the Rth retardation value have a small change due to environmental humidity.
Difference between Re retardation value and Rth retardation value measured under 25 ° C. and 10% RH environment and Re retardation value measured under 25 ° C. and 80% RH environment (Re10% −Re80% (25 ° C.)), Rth letter The difference in the retardation value (Rth 10% −Rth 80% (25 ° C.)) is also preferably small, preferably within 25 nm and within 70 nm, respectively. Further, Re 10% -Re 80% (25 ° C.) is preferably within 15 nm, and Rth 10% -Rth 80% (25 ° C.) is preferably within 50 nm. In particular, Re 10% -Re 80% (25 ° C.) is within 10 nm. Rth 10% -Rth 80% (25 ° C.) is preferably within 40 nm.

[Moisture permeability]
For example, moisture permeability per unit area is adjusted according to JIS Z-0208 using a moisture permeation test apparatus (KK-709007, Toyo Seiki Co., Ltd.) by adjusting the humidity of a sample 70 mmΦ at 25 ° C. and 90% RH for 24 hours. Calculate (g / m ² )
Moisture permeability = weight after humidity control-weight before humidity control.
The moisture permeability at 25 ° C. and 90% RH is preferably 20 g / m ² · 24 hr to 250 g / m ² · 24 hr, more preferably 20 g / m ² · 24 hr to 230 g / m ² · 24 hr. .

[Dimension change rate]
For example, the dimensional change rate can be obtained as follows. Three test pieces each having a width of 30 mm and a length of 120 mm are collected from the vertical direction and the horizontal direction of the sample. Holes of 6 mmΦ are punched at 100 mm intervals on both ends of the test piece. This is conditioned for 2 hours or more in a room at 23 ± 3 ° C. and a relative humidity of 65 ± 5%. Using an automatic pin gauge (manufactured by Shinto Kagaku Co., Ltd.), the original size (L1) of the punch interval is measured to the minimum scale / 1000 mm. Next, the test piece was suspended in a 90 ° C ± 1 ° C incubator for 24 hours and heat-conditioned for 2 hours or more in a room at 23 ± 3 ° C and relative humidity 65 ± 5%. The punch spacing dimension (L2) is measured. The dimensional change is calculated by the following formula.
Dimensional change rate = (L2-L1 / L1) × 100

[High humidity dimensional change rate]
High humidity dimensional change rate For example, it can obtain | require as follows. Three test pieces each having a width of 30 mm and a length of 120 mm are collected from the vertical direction and the horizontal direction of the sample. Holes of 6 mmΦ are punched at 100 mm intervals on both ends of the test piece. This is conditioned for 2 hours or more in a room at 23 ± 3 ° C. and a relative humidity of 65 ± 5%. Using an automatic pin gauge (manufactured by Shinto Kagaku Co., Ltd.), the original size (L1) of the punch interval is measured to the minimum scale / 1000 mm. Next, suspend the test piece in a constant temperature and humidity chamber at 60 ° C ± 1 ° C and relative humidity 90 ± 5% and heat-treat it for 24 hours, and adjust the humidity for 2 hours or more in a room at 23 ± 3 ° C and relative humidity 65 ± 5%. After that, the dimension (L3) of the punch interval after the heat treatment is measured with an automatic pin gauge. The dimensional change is calculated by the following formula.
Dimensional change rate = (L3-L1 / L1) × 100
It is desired that the dimensional changes at 90 ° C. Dry and 60 ° C. and 90% are both small, preferably within −0.2%, and more preferably within −0.15%.

[Surface treatment of cellulose acetate film]
The surface energy of the cellulose acetate film is preferably 55 to 75 mN / m, and for that purpose, surface treatment is preferably performed. Examples of the surface treatment include saponification treatment, plasma treatment, flame treatment, and ultraviolet irradiation treatment. Saponification treatment includes acid saponification treatment and alkali saponification treatment. Plasma treatment includes corona discharge treatment and glow discharge treatment. In order to maintain the flatness of the film, in these surface treatments, it is preferable that the temperature of the cellulose acetate film is not higher than the glass transition temperature (Tg), specifically 150 ° C. or lower. The surface energy of the cellulose acetate film after these surface treatments is preferably 55 to 75 mN / m.
The glow discharge treatment may be low-temperature plasma that occurs in a low pressure gas of 10 ^{−3 to} 20 Torr, and plasma treatment under atmospheric pressure is also preferable. A plasma-excitable gas is a gas that is plasma-excited under the above conditions, and examples thereof include chlorofluorocarbons such as argon, helium, neon, krypton, xenon, nitrogen, carbon dioxide, and tetrafluoromethane, and mixtures thereof. It is done. Details of these are described in detail in pages 30 to 32 in the Japan Institute of Invention Disclosure Technical Bulletin (Public Technical Number 2001-1745, published on March 15, 2001, Invention Association). In the plasma treatment at atmospheric pressure, which has been attracting attention in recent years, for example, irradiation energy of 20 to 500 kGy is used under 10 to 1000 keV, and more preferably irradiation energy of 20 to 300 kGy is used under 30 to 500 keV. Among these, an alkali saponification treatment is particularly preferable, and it is extremely effective as a surface treatment of a cellulose acylate film.

  The alkali saponification treatment is preferably carried out by a method of directly immersing the cellulose acylate film in a saponification solution tank or a method of applying a saponification solution to the cellulose acylate film. Examples of the coating method include a dip coating method, a curtain coating method, an extrusion coating method, a bar coating method, and an E-type coating method. The solvent of the alkali saponification coating solution has good wettability because it is applied to the transparent support of the saponification solution, and the surface state remains good without forming irregularities on the surface of the transparent support by the saponification solution solvent. It is preferred to select a solvent to keep. Specifically, an alcohol solvent is preferable, and isopropyl alcohol is particularly preferable. An aqueous solution of a surfactant can also be used as a solvent. The alkali of the alkali saponification coating solution is preferably an alkali that dissolves in the above solvent, and more preferably KOH or NaOH. The pH of the saponification coating solution is preferably 10 or more, more preferably 12 or more. The reaction conditions during alkali saponification are preferably 1 second to 5 minutes at room temperature, more preferably 5 seconds to 5 minutes, and particularly preferably 20 seconds to 3 minutes. After the alkali saponification reaction, it is preferable to wash the surface on which the saponification solution is applied with water or with an acid and then with water.

  The surface energy of the solid obtained by these methods can be determined by the contact angle method, the wet heat method, and the adsorption method as described in “Basics and Applications of Wetting” (Realize 1989.12.10). . In the case of the cellulose acetate film of the present invention, the contact angle method is preferably used. Specifically, two types of solutions having known surface energies are dropped on a cellulose acetate film, and at the intersection between the surface of the droplet and the film surface, the angle formed by the tangent line drawn on the droplet and the film surface The surface angle of the film can be calculated by defining the angle containing the droplet as the contact angle.

  By subjecting the cellulose acetate film to the above surface treatment, a cellulose acetate film having a surface energy of 55 to 75 mN / m can be obtained. By using this cellulose acetate film as a transparent protective film for a polarizing plate, the adhesion between the polarizing film and the cellulose acetate film can be improved. When the cellulose acetate film of the present invention is used in an OCB mode liquid crystal display device, the optical compensation sheet of the present invention forms an alignment film on the cellulose acetate film and includes a discotic compound or a rod-shaped liquid crystal compound on the alignment film. An optically anisotropic layer may be provided. The optically anisotropic layer is formed by aligning a discotic compound (or rod-shaped liquid crystal compound) on the alignment film and fixing the alignment state. Thus, when providing an optically anisotropic layer on a cellulose acetate film, conventionally, in order to ensure the adhesion between the cellulose acetate film and the alignment film, it was necessary to provide a gelatin undercoat layer between them. By using a cellulose acetate film having a surface energy of 55 to 75 mN / m according to the present invention, a gelatin undercoat layer can be dispensed with.

  The above-described retardation values Re, Rth, and Re are stretched to include at least one compound represented by the general formula (I) and at least one cyclic compound having at least three substituents as described above. The cellulose acylate film satisfying the / Rth ratio and having a film thickness of 20 μm to 160 μm functions as an optical compensation sheet with only one sheet.

[Polarizer]
A polarizing plate consists of a polarizing film and two transparent protective films arrange | positioned at the both sides. As one protective film, an optical compensation sheet made of the cellulose acylate film can be used. A normal cellulose acetate film may be used for the other protective film.
Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally manufactured using a polyvinyl alcohol film.
The slow axis of the optical compensation sheet made of cellulose acylate film and the transmission axis of the polarizing film are arranged so as to be substantially parallel.

[Change in polarization degree]
The performance of the polarizing plate is evaluated by a single plate transmittance defined by the following formula (3) and a polarization degree defined by the following formula (5).
The above-mentioned single plate 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 system τ (λ): spectral transmittance formula (5)

平行透過率、直交透過率は、上述の単板透過率同様、数式（３）で定義される。

The parallel transmittance and the orthogonal transmittance are defined by Equation (3) as in the case of the single plate transmittance described above.

Since the polarizing plate withstands use under high humidity conditions, it is required that the degree of polarization change little even when left under high humidity conditions. In the present invention, the degree of polarization before and after aging for 500 hours in an atmosphere of 60 ° C. and 95% RH was measured, and the change in the degree of polarization was examined according to the following formula (6). Each transmittance was measured with a Shimadzu spectrophotometer UV3100.
Polarization degree change = polarization degree of the sample after time-polarization degree of the sample before the time expression (6)
When the cellulose acetate film of the present invention is used as a polarizing plate protective film, the change in the degree of polarization after aging for 500 hours at 60 ° C. and 95% RH is preferably within 3%, more preferably within 2%. .

[Antireflection layer]
It is preferable to provide an antireflection layer on the transparent protective film disposed on the opposite side of the polarizing plate from the liquid crystal cell. In particular, in the present invention, at least a light scattering layer and a low refractive index layer are laminated in this order on the transparent protective film, or a medium refractive index layer, a high refractive index layer, and a low refractive index layer are arranged in this order on the transparent protective film. The antireflection layer laminated with is preferably used. Preferred examples thereof are described below.

A preferred example of an antireflection layer in which a light scattering layer and a low refractive index layer are provided on a transparent protective film will be described.
In the light scattering layer of the present invention, mat particles are dispersed, and the refractive index of the material other than the mat particles in the light scattering layer is preferably in the range of 1.50 to 2.00. The refractive index of the layer is preferably in the range of 1.35 to 1.49. In the present invention, the light scattering layer has both antiglare properties and hard coat properties, and may be a single layer or a plurality of layers, for example, 2 to 4 layers.

  The antireflection layer has an uneven surface shape with a center line average roughness Ra of 0.08 to 0.40 μm, a 10-point average roughness Rz of 10 times or less of Ra, an average mountain valley distance Sm of 1 to 100 μm, and an uneven depth. Designed so that the standard deviation of the height of the convex part from the part is 0.5 μm or less, the standard deviation of the average mountain valley distance Sm with respect to the center line is 20 μm or less, and the surface with an inclination angle of 0 to 5 degrees is 10% or more. By doing so, sufficient anti-glare properties and a visually uniform matte feeling are achieved, which is preferable. Further, the ratio of the minimum value and the maximum value of the reflectance in the range of the a * value −2 to 2, the b * value −3 to 3, and the 380 nm to 780 nm in the color of the reflected light under the C light source is 0.5. By being -0.99, the color of reflected light becomes neutral, which is preferable. Moreover, it is preferable that the b * value of the transmitted light under the C light source is 0 to 3 because the yellow color of white display when applied to a display device is reduced. In addition, when a 120 μm × 40 μm grid is inserted between the surface light source and the antireflection film of the present invention and the luminance distribution is measured on the film, the standard deviation of the luminance distribution is 20 or less. Glare when applying the film of the present invention is reduced, which is preferable.

  The optical properties of the antireflection layer of the present invention are such that the specular reflectance is 2.5% or less, the transmittance is 90% or more, and the 60 ° glossiness is 70% or less. Is preferable. In particular, the specular reflectance is more preferably 1% or less, and most preferably 0.5% or less. Haze 20% to 50%, internal haze / total haze value 0.3 to 1, haze value after formation of low refractive index layer from haze value to light scattering layer within 15%, comb width at 0.5 mm Transmission image clarity 20% to 50%, vertical transmission light / transmittance ratio of 2 degrees from vertical to 1.5 to 5.0 prevents glare on high-definition LCD panels, characters, etc. Reduction of blur is achieved, which is preferable.

[Low refractive index layer]
The refractive index of the low refractive index layer of the antireflection film of the present invention is 1.20 to 1.49, preferably 1.30 to 1.44. Further, the low refractive index layer preferably satisfies the following formula (III) from the viewpoint of reducing the reflectance.
Formula (III)
(M / 4) × 0.7 <n1d1 <(m / 4) × 1.3
In the formula, m is a positive odd number, n1 is the refractive index of the low refractive index layer, and d1 is the film thickness (nm) of the low refractive index layer. Further, λ is a wavelength, which is a value in the range of 500 to 550 nm.

The material for forming the low refractive index layer of the present invention will be described below.
The low refractive index layer of the present invention contains a fluorine-containing polymer as a low refractive index binder. The fluorine polymer is preferably a fluorine-containing polymer that is crosslinked by heat or ionizing radiation with a coefficient of dynamic friction of 0.03 to 0.20, a contact angle with water of 90 to 120 °, and a sliding angle of pure water of 70 ° or less. When the antireflection film of the present invention is mounted on an image display device, the lower the peel strength from a commercially available adhesive tape, the easier it is to peel off after sticking a seal or memo, preferably 500 gf or less, more preferably 300 gf or less, 100 gf or less is most preferable. Further, the higher the surface hardness measured with a microhardness meter, the harder it is to scratch, preferably 0.3 GPa or more, more preferably 0.5 GPa or more.

  Examples of the fluorine-containing polymer used in the low refractive index layer include hydrolysis and dehydration condensate of perfluoroalkyl group-containing silane compounds (for example, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane). And a fluorine-containing copolymer having a fluorine-containing monomer unit and a structural unit for imparting crosslinking reactivity as structural components.

  Specific examples of the fluorine-containing monomer unit include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, perfluorooctylethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole. Etc.), partially (meth) acrylic acid or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemical), M-2020 (manufactured by Daikin), etc.), fully or partially fluorinated vinyl ethers, etc. However, perfluoroolefins are preferred, and hexafluoropropylene is particularly preferred from the viewpoints of refractive index, solubility, transparency, availability, and the like.

  As structural units for imparting crosslinking reactivity, structural units obtained by polymerization of monomers having a self-crosslinkable functional group in advance in the molecule such as glycidyl (meth) acrylate and glycidyl vinyl ether, carboxyl groups, hydroxy groups, amino groups , Obtained by polymerization of a monomer having a sulfo group or the like (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, maleic acid, crotonic acid, etc.) And a structural unit obtained by introducing a crosslinking reactive group such as a (meth) acryloyl group into these structural units by a polymer reaction (for example, it can be introduced by a technique such as allowing acrylic acid chloride to act on a hydroxy group) And the like.

  In addition to the above-mentioned fluorine-containing monomer units and structural units for imparting crosslinking reactivity, monomers not containing fluorine atoms can be copolymerized as appropriate from the viewpoints of solubility in solvents and film transparency. There are no particular limitations on the monomer units that can be used in combination. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, acrylic acid 2) -Ethylhexyl), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, vinyl toluene, α-methylstyrene, etc.), vinyl ethers (methyl) Vinyl ether, ethyl vinyl ether, cyclohexyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate etc.), acrylamides (N-tert-butylacrylamide, N- Black hexyl acrylamide), methacrylamides, and acrylonitrile derivatives.

  As described in JP-A-10-25388 and JP-A-10-147739, a curing agent may be appropriately used in combination with the above polymer.

[Light scattering layer]
The light scattering layer is formed for the purpose of contributing to the film light diffusibility due to surface scattering and / or internal scattering and hard coat properties for improving the scratch resistance of the film. Therefore, it is formed including a binder for imparting hard coat properties, matte particles for imparting light diffusibility, and inorganic fillers for increasing the refractive index, preventing crosslinking shrinkage, and increasing the strength as necessary. The

  The thickness of the light scattering layer is preferably 1 to 10 μm and more preferably 1.2 to 6 μm for the purpose of imparting hard coat properties. If it is too thin, the hard property will be insufficient, and if it is too thick, curling and brittleness will deteriorate and the workability will be insufficient.

  The binder of the scattering layer is preferably a polymer having a saturated hydrocarbon chain or a polyether chain as the main chain, and more preferably a polymer having a saturated hydrocarbon chain as the main chain. The binder polymer preferably has a crosslinked structure. As the binder polymer having a saturated hydrocarbon chain as a main chain, a polymer of an ethylenically unsaturated monomer is preferable. As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable. In order to make the binder polymer have a high refractive index, the monomer structure contains an aromatic ring, at least one atom selected from halogen atoms other than fluorine, sulfur atoms, phosphorus atoms, and nitrogen atoms. You can also choose.

  Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid (eg, ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di ( (Meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra (meth) acrylate), pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol Tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-si Rhohexanetetramethacrylate, polyurethane polyacrylate, polyester polyacrylate), modified ethylene oxide, vinylbenzene and derivatives thereof (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1, 4-divinylcyclohexanone), vinylsulfone (eg, divinylsulfone), acrylamide (eg, methylenebisacrylamide) and methacrylamide. Two or more of these monomers may be used in combination.

  Specific examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like. Two or more of these monomers may be used in combination.

Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photo radical initiator or a thermal radical initiator.
Accordingly, a coating liquid containing a monomer having an ethylenically unsaturated group, a photo radical initiator or a thermal radical initiator, mat particles, and an inorganic filler is prepared, and the coating liquid is applied on a transparent support and then ionizing radiation or heat is applied. The antireflection film can be formed by curing by the polymerization reaction. As these photo radical initiators, known ones can be used.

The polymer having a polyether as the main chain is preferably a ring-opening polymer of a polyfunctional epoxy compound. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photoacid generator or a thermal acid generator.
Accordingly, a coating liquid containing a polyfunctional epoxy compound, a photoacid generator or a thermal acid generator, matte particles and an inorganic filler is prepared, and the coating liquid is applied onto a transparent support and then subjected to a polymerization reaction by ionizing radiation or heat. Curing can form an antireflection film.

Instead of or in addition to a monomer having two or more ethylenically unsaturated groups, a monomer having a crosslinkable functional group is used to introduce a crosslinkable functional group into the polymer, and by reaction of this crosslinkable functional group, A crosslinked structure may be introduced into the binder polymer.
Examples of the crosslinkable functional group include isocyanate group, epoxy group, aziridine group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, methylol group and active methylene group. Vinylsulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester and urethane, and metal alkoxide such as tetramethoxysilane can also be used as a monomer for introducing a crosslinked structure. A functional group that exhibits crosslinkability as a result of the decomposition reaction, such as a block isocyanate group, may be used. That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition.
These binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.

For the purpose of imparting anti-glare properties, the light scattering layer contains matte particles having an average particle diameter of 1 to 10 μm, preferably 1.5 to 7.0 μm, such as inorganic compound particles or resin particles, than filler particles. Is done.
As specific examples of the mat particles, inorganic particles such as silica particles and TiO ₂ particles; resin particles such as acrylic particles, crosslinked acrylic particles, polystyrene particles, crosslinked styrene particles, melamine resin particles, and benzoguanamine resin particles are preferable. Can be mentioned. Of these, crosslinked styrene particles, crosslinked acrylic particles, crosslinked acrylic styrene particles, and silica particles are preferable.
The shape of the mat particles can be either spherical or irregular.

  Two or more kinds of mat particles having different particle diameters may be used in combination. It is possible to impart anti-glare properties with mat particles having a larger particle size and to impart other optical characteristics with mat particles having a smaller particle size.

  Furthermore, the particle size distribution of the mat particles is most preferably monodisperse, and the particle sizes of the particles are preferably closer to each other. For example, when particles having a particle size of 20% or more than the average particle size are defined as coarse particles, the proportion of coarse particles is preferably 1% or less of the total number of particles, more preferably 0.1%. Or less, more preferably 0.01% or less. Matt particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and a matting agent having a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree of classification.

The mat particles are contained in the light scattering layer so that the amount of mat particles in the formed light scattering layer is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² .
The particle size distribution of the mat particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution.

The light scattering layer is made of an oxide of at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony, in addition to the above mat particles, in order to increase the refractive index of the layer. Thus, it is preferable that an inorganic filler having an average particle size of 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.06 μm or less is contained.
Conversely, in order to increase the refractive index difference from the mat particles, it is also preferable to use a silicon oxide in order to keep the refractive index of the layer low in the light scattering layer using the high refractive index mat particles. The preferred particle size is the same as that of the aforementioned inorganic filler.
Specific examples of the inorganic filler to be used in the light scattering _{layer, TiO 2, ZrO 2, Al} 2 O 3, In 2 O 3, ZnO, SnO 2, Sb 2 O 3, ITO and SiO ₂ and the like. TiO ₂ and ZrO ₂ are particularly preferable from the viewpoint of increasing the refractive index. The surface of the inorganic filler is preferably subjected to a silane coupling treatment or a titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with a binder species on the filler surface is preferably used.
The amount of these inorganic fillers added is preferably 10 to 90% of the total mass of the light scattering layer, more preferably 20 to 80%, and particularly preferably 30 to 75%.
Such a filler does not scatter because the particle size is sufficiently smaller than the wavelength of light, and a dispersion in which the filler is dispersed in a binder polymer behaves as an optically uniform substance.

  The bulk refractive index of the mixture of binder and inorganic filler in the light scattering layer is preferably 1.48 to 2.00, more preferably 1.50 to 1.80. In order to make the refractive index within the above range, the kind and amount ratio of the binder and the inorganic filler may be appropriately selected. How to select can be easily known experimentally in advance.

  In order to ensure surface uniformity such as coating unevenness, drying unevenness, point defects, etc., the light scattering layer should be coated with either a fluorine-based surfactant or a silicone-based surfactant, or both for forming an antiglare layer. Contained in the composition. In particular, a fluorine-based surfactant is preferably used because an effect of improving surface defects such as coating unevenness, drying unevenness, and point defects of the antireflection film of the present invention appears in a smaller addition amount. The purpose is to increase productivity by giving high-speed coating suitability while improving surface uniformity.

Next, an antireflection layer in which a middle refractive index layer, a high refractive index layer, and a low refractive index layer are laminated in this order on the transparent protective film will be described.
An antireflection film having a layer structure of at least a medium refractive index layer, a high refractive index layer, and a low refractive index layer (outermost layer) on the substrate is designed to have a refractive index satisfying 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 Alternatively, a hard coat layer is provided between the transparent support and the intermediate refractive index layer. Also good. Further, it may comprise a medium refractive index hard coat layer, a high refractive index layer and a low refractive index layer.
Examples thereof include JP-A Nos. 8-122504, 8-110401, 10-300902, JP-A 2002-243906, JP-A 2000-11706, and the like. Other functions may be imparted to each layer, for example, an antifouling low refractive index layer or an antistatic high refractive index layer (eg, JP-A-10-206603, JP-A-2002). -243906 publication etc.) etc. are mentioned.
The haze of the antireflection film is preferably 5% or less, more preferably 3% or less. Further, the strength 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 K5400.

[High refractive index layer and medium refractive index layer]
The layer having a high refractive index of the antireflection film is composed of a curable film containing at least an ultrafine particle of an inorganic compound having a high refractive index having an average particle size of 100 nm or less and a matrix binder.
Examples of the high refractive index inorganic compound fine particles include inorganic compounds having a refractive index of 1.65 or more, preferably those having a refractive index of 1.9 or more. Examples thereof include oxides such as Ti, Zn, Sb, Sn, Zr, Ce, Ta, La, and In, and composite oxides containing these metal atoms.
In order to obtain such ultrafine particles, the surface of the particles is treated with a surface treatment agent (for example, silane coupling agents, etc .: JP-A Nos. 1-295503, 11-153703, 2000-9908). , Anionic compounds or organometallic coupling agents: JP 2001-310432 A, etc., core-shell structure with high refractive index particles as the core (JP 2001-166104 A, etc.), specific dispersant combined use (E.g., Japanese Patent Laid-Open No. 11-153703, Japanese Patent No. US6210858B1, Japanese Patent Laid-Open No. 2002-27776069, etc.).
Examples of the material forming the matrix include conventionally known thermoplastic resins and curable resin films.
Furthermore, it is selected from a polyfunctional compound-containing composition containing at least two radically polymerizable and / or cationically polymerizable groups, an organometallic compound containing a hydrolyzable group, and a partial condensate composition thereof. At least one composition is preferred. Examples thereof include compounds described in JP-A Nos. 2000-47004, 2001-315242, 2001-31871, and 2001-296401.
A curable film obtained from a colloidal metal oxide obtained from a hydrolyzed condensate of metal alkoxide and a metal alkoxide composition is also preferred. For example, it describes in Unexamined-Japanese-Patent No. 2001-293818.
The refractive index of the high refractive index layer is generally 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 thickness is preferably 5 nm to 10 μm, and more preferably 10 nm to 1 μm.

[Low refractive index layer]
The low refractive index layer is formed by sequentially laminating on the high refractive index layer. The refractive index of the low refractive index layer is 1.20 to 1.55. Preferably it is 1.30-1.50.
It is preferable to construct as the outermost layer having scratch resistance and antifouling property. As means for greatly improving the scratch resistance, it is effective to impart slipperiness to the surface, and conventionally known thin film layer means such as introduction of silicone or introduction of fluorine can be applied.
The refractive index of the fluorine-containing compound is preferably 1.35 to 1.50. More preferably, it is 1.36-1.47. The fluorine-containing compound is preferably a compound containing a crosslinkable or polymerizable functional group containing fluorine atoms in the range of 35 to 80% by mass.
For example, paragraph numbers [0018] to [0026] of Japanese Patent Application Laid-Open No. 9-222503, paragraph numbers [0019] to [0030] of Japanese Patent Application Laid-Open No. 11-38202, and paragraph numbers of Japanese Patent Application Laid-Open No. 2001-40284. [0027] to [0028], compounds described in JP-A No. 2000-284102, and the like.
The silicone compound is a compound having a polysiloxane structure, preferably containing a curable functional group or a polymerizable functional group in the polymer chain and having a crosslinked structure in the film. For example, reactive silicone (eg, Silaplane (manufactured by Chisso Corporation), silanol group-containing polysiloxane (Japanese Patent Laid-Open No. 11-258403, etc.) and the like can be mentioned.
The crosslinking or polymerization reaction of the fluorine-containing and / or siloxane polymer having a crosslinking or polymerizable group is performed simultaneously with or after the application of the coating composition for forming the outermost layer containing a polymerization initiator, a sensitizer and the like. It is preferable to carry out by light irradiation or heating.
A sol-gel cured film is also preferred in which an organometallic compound such as a silane coupling agent and a specific fluorine-containing hydrocarbon group-containing silane coupling agent are cured by a condensation reaction in the presence of a catalyst.
For example, a polyfluoroalkyl group-containing silane compound or a partially hydrolyzed condensate thereof (Japanese Patent Laid-Open Nos. 58-142958, 58-147483, 58-147484, Japanese Patent Laid-Open Nos. 9-157582, 11) -106704), silyl compounds containing a poly "perfluoroalkyl ether" group which is a fluorine-containing long chain group (Japanese Patent Application Laid-Open Nos. 2000-117902, 2001-48590, 2002) 53804), and the like.
The low refractive index layer has an average primary particle diameter of 1 to 150 nm such as a filler (for example, silicon dioxide (silica), fluorine-containing particles (magnesium fluoride, calcium fluoride, barium fluoride)) as an additive other than the above. A low refractive index inorganic compound, organic fine particles described in paragraphs [0020] to [0038] of JP-A-11-3820), silane coupling agents, slip agents, surfactants, and the like.
When the low refractive index layer is positioned below the outermost layer, 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.). The coating method is preferable because it can be manufactured at a low cost.
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.

[Other layers of antireflection layer]
Further, a hard coat layer, a forward scattering layer, a primer layer, an antistatic layer, an undercoat layer, a protective layer, and the like may be provided.

[Hard coat layer]
The hard coat layer is provided on the surface of the transparent support in order to impart physical strength to the transparent protective film provided with the antireflection layer. In particular, it is preferably provided 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 a light and / or heat curable compound.
The curable functional group is preferably a photopolymerizable functional group, and the hydrous functional group-containing organometallic compound is preferably an organic alkoxysilyl compound.
Specific examples of these compounds are the same as those exemplified for the high refractive index layer.
Specific examples of the constituent composition of the hard coat layer include those described in JP-A Nos. 2002-144913, 2000-9908, and WO00 / 46617.
The high refractive index layer can also serve as a hard coat layer. In such a case, it is preferable to form fine particles dispersed in the hard coat layer using the method described for the high refractive index layer.
A hard-coat layer can also serve as the glare-proof layer (after-mentioned) which contained the particle | grains with an average particle diameter of 0.2-10 micrometers and provided the glare-proof function (anti-glare function).
The film thickness of the hard coat layer can be appropriately designed depending on the application. The film thickness of the hard coat layer is preferably 0.2 to 10 μm, more preferably 0.5 to 7 μm.
The strength of the hard coat layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in a pencil hardness test according to JIS K5400. Further, in the Taber test according to JIS K5400, the smaller the amount of wear of the test piece before and after the test, the better.

[Antistatic layer]
When an antistatic layer is provided, it is preferable to impart conductivity with a volume resistivity of 10 ⁻⁸ (Ωcm ⁻³ ) or less. The use of hygroscopic substances, water-soluble inorganic salts, certain surfactants, cationic polymers, anionic polymers, colloidal silica, etc. can give a volume resistivity of 10 ⁻⁸ (Ωcm ⁻³ ). There is a problem that dependency is large, and sufficient conductivity cannot be secured at low humidity. Therefore, a metal oxide is preferable as the conductive layer material. Some metal oxides are colored, but using these metal oxides as the conductive layer material is not preferable because the entire film is colored. Zn, Ti, Al, In, Si, Mg, Ba, Mo, W, or V can be cited as the metal that forms the metal oxide without coloration. Use a metal oxide based on this. Is preferred. Specific examples include ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₃ , V ₂ O ₅ , or a composite oxide thereof. In particular, ZnO, TiO ₂ , and SnO ₂ are preferable. Examples of containing different atoms include, for example, additives such as Al and In for ZnO, addition of Sb, Nb and halogen elements for SnO ₂ , and addition of Nb and TA for TiO ₂ . Addition is effective. Furthermore, as described in Japanese Examined Patent Publication No. 59-6235, a material obtained by adhering the above metal oxide to other crystalline metal particles or fibrous materials (for example, titanium oxide) may be used. The volume resistance value and the surface resistance value are different physical properties and cannot be simply compared. However, in order to secure a conductivity of 10 ⁻⁸ (Ωcm ⁻³ ) or less in volume resistance, It is sufficient that the layer has a surface resistance value of about 10 ⁻¹⁰ (Ω / cm ³ ) or less, and more preferably 10 ⁻⁸ (Ω / cm ³ ). The surface resistance value of the conductive layer needs to be measured as a value when the antistatic layer is the outermost layer, and can be measured in the middle of forming the laminated film described in this patent.

[Liquid Crystal Display]
The polarizing plate using the cellulose acylate film of the present invention is advantageously used in a liquid crystal display device. The polarizing plate of the present invention can be used for liquid crystal cells in various display modes. TN (Twisted Nematic), IPS (In-Plane Switching), FLC (Ferroelectric Liquid Crystal, AFLC) Various display modes such as HAN (Hybrid Aligned Nematic) have been proposed. Of these, the OCB mode or the VA mode can be preferably used.

  The OCB mode liquid crystal cell is a liquid crystal display device using a bend alignment mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned in a substantially opposite direction (symmetrically) between an upper portion and a lower portion of the liquid crystal cell. OCB mode liquid crystal cells are disclosed in US Pat. Nos. 4,583,825 and 5,410,422. Since the rod-like liquid crystal molecules are aligned symmetrically between the upper part and the lower part of the liquid crystal cell, the bend alignment mode liquid crystal cell has a self-optical compensation function. For this reason, this liquid crystal mode is also called an OCB (Optically Compensatory Bend) liquid crystal mode. The bend alignment mode liquid crystal display device has an advantage of high response speed.

In a VA mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially vertically when no voltage is applied.
The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). 176625) (2) Liquid crystal cell (SID97, Digest of tech. Papers (Preliminary Proceed) 28 (1997) 845 in which the VA mode is made into a multi-domain (MVA mode) for widening the viewing angle ), (3) Liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary collections 58-59 of the Japanese Liquid Crystal Society) (1998)) and (4) SURVAVAL mode liquid crystal cells (announced at LCD International 98).
In the OCB mode and VA mode liquid crystal display devices, the liquid crystal cell and two polarizing plates of the present invention may be disposed on both sides thereof. In the VA mode, the polarizing plate of the present invention is disposed on the backlight side of the cell. You may arrange. Also in that case, it is preferable to dispose the cellulose acylate film of the present invention on the liquid crystal cell side. The liquid crystal cell carries a liquid crystal between two electrode substrates.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to an Example.

Example 1
[Production of Cellulose Acylate Film A1]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetylation degree of 60.9 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 318 parts by weight Methanol (second Solvent) 47 parts by mass silica (particle size 0.2 μm) 0.1 parts by mass

Into another mixing tank, 10 parts by mass of the following retardation control agent A, 10 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and stirred while heating. A foundation control agent solution 01 was prepared.
37.4 parts by mass of the retardation control (raising) solution 01 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of the retardation adjusting agents A and B was 3 parts by mass with respect to 100 parts by mass of cellulose acetate.

Retardation control agent A

Retardation control agent B

  The obtained dope was cast using a band casting machine. A film having a residual solvent amount of 32% by mass at the start of stretching was laterally stretched at a stretch ratio of 26% using a tenter under the conditions of 130 ° C. to prepare a cellulose acetate film (thickness: 92 μm). About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). The results are shown in Table 1. Table 1 also shows the results of measuring the wavelength dispersion shape, the humidity dependency of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate.

Example 2
[Preparation of cellulose acylate film A2]
A cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1 except that the stretching ratio was 30%. About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 3
[Creation of cellulose acylate film A3]
A cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1 except that the film thickness after stretching was 80 μm. About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 4
[Preparation of cellulose acylate film A4]
A cellulose acetate film (thickness: 92 μm) was prepared in the same manner as in Example 1, except that 474 parts by mass of the cellulose acetate solution was mixed with 31.3 parts by mass of the retardation control (raising) agent solution 01. The addition amount of retardation adjusting agents A and B in the dope was 2.6 parts by mass with respect to 100 parts by mass of cellulose acetate.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 5
[Preparation of cellulose acylate film A5]
2.9 parts by mass of the above-mentioned retardation control agent A, 17.1 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride, and 13 parts by mass of methanol are added to the mixing tank and stirred while heating. A retardation controlling agent solution 02 was prepared.
42.2 parts by mass of the retardation control (raising) agent solution 02 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 1 part by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 6 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 18% at the start of stretching. A cellulose acetate film (thickness: 92 μm) was prepared in the same manner as in Example 1 except that the draw ratio was 25%.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 6
[Preparation of cellulose acylate film A6]
Into the mixing tank, 8 parts by mass of the above-mentioned retardation control agent A, 12 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating to control the retardation. Agent solution 03 was prepared.
30.1 parts by mass of the retardation control (raising) agent solution 03 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 2 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 3 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off, and stretched laterally with a tenter stretching machine at a residual solvent amount of 34% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 93 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 7
[Preparation of cellulose acylate film A7]
14.3 parts by mass of the above-mentioned retardation control agent A, 5.7 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride, and 13 parts by mass of methanol are added to the mixing tank and stirred while heating. A retardation control agent solution 04 was prepared.
42.2 parts by mass of the retardation control (raising) agent solution 04 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 5 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 2 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 30% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 91 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 8
[Preparation of cellulose acylate film A8]
In the mixing tank, 5 parts by mass of the above-mentioned retardation control agent A, 5 parts by mass of the following retardation control agent C, 10 parts by mass of the above-mentioned retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol And stirred while heating to prepare a retardation control agent solution 05.
37.4 parts by mass of the retardation control (raising) agent solution 05 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A is 1.5 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation control agent C is 1.5 parts by mass with respect to 100 parts by mass of cellulose acetate. The amount of B added was 3 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Retardation control agent C

Example 9
[Preparation of cellulose acylate film A9]
In the mixing tank, 10 parts by mass of the above-mentioned retardation control agent A, 5 parts by mass of retardation control agent B, 5 parts by mass of retardation control agent D of the following formula, 87 parts by mass of methylene chloride and 13 parts by mass of methanol The solution was added and stirred while heating to prepare a retardation controlling agent solution 06.
36.2 parts by mass of the retardation control (raising) solution 06 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of the retardation adjusting agent A is 3 parts by mass with respect to 100 parts by mass of the cellulose acetate, and the addition amount of the retardation control agent B is 1.5 parts by mass with respect to 100 parts by mass of the cellulose acetate. The addition amount was 1.5 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 33% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 93 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Retardation control agent D

Example 10
[Creation of cellulose acylate film A10]
Into the mixing tank, 10 parts by mass of the above-mentioned retardation control agent C, 10 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating to control the retardation. Agent solution 07 was prepared.
36.2 parts by mass of the retardation control (raising) solution 07 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of retardation control agent C was 3 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation control agent B was 3 parts by mass with respect to 100 parts by mass of cellulose acetate.

After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 31% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 92 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 11
[Preparation of cellulose acylate film A11]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate propionate having a substitution degree of acetyl group of 1.90 and a substitution degree of propionyl group of 0.80 100 parts by weight Triphenyl phosphate 8.5 parts by weight Ethylphthalyl ethyl glycolate 2.0 parts by weight Methylene chloride 290 parts by weight 60 parts by mass of ethanol

In another mixing tank, 5 parts by mass of cellulose acetate propionate, 6 parts by mass of Tinuvin 326 (manufactured by Ciba Specialty Chemicals), 4 parts by mass of Tinuvin 109 (manufactured by Ciba Specialty Chemicals), chinuvin 171 (manufactured by Ciba Specialty Chemicals), 8.3 parts by mass of the above-mentioned retardation control agent A, 8.3 parts by mass of retardation control agent B, 94 parts by mass of methylene chloride and ethanol 8 parts by mass was added and stirred while heating to prepare additive solution 1.
The dope was prepared by mixing 73 parts by mass of the additive solution 1 with 474 parts by mass of the cellulose acetate solution and stirring sufficiently.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. A draw ratio was set to 26%, and a cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 12
[Preparation of cellulose acylate film A12]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate propionate having a substitution degree of acetyl group of 0.18 and a substitution degree of propionyl group of 2.47 100 parts by weight Triphenyl phosphate 8.0 parts by weight Ethylphthalylethyl glycolate 4.0 parts by weight Methylene chloride 403 parts by weight 60.3 parts by mass of ethanol

Into another mixing tank, 12.0 parts by mass of the above-mentioned retardation control agent A, 8.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of ethanol were added and heated. Stir to prepare additive solution 2.
The dope was prepared by mixing 9.9 parts by mass of additive solution 2 with 474 parts by mass of the cellulose acetate solution and stirring sufficiently.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. A draw ratio was 23%, and a cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 13
[Preparation of cellulose acylate film A13]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate butyrate having a substitution degree of acetyl group of 1.40 and a substitution degree of butyryl group of 1.30 100 parts by weight Triphenyl phosphate 8.5 parts by weight Ethylphthalyl ethyl glycolate 2.0 parts by weight Methylene chloride 290 parts by weight Ethanol 60 parts by mass

In another mixing tank, 5 parts by mass of cellulose acetate butyrate, 6 parts by mass of Tinuvin 326 (manufactured by Ciba Specialty Chemicals), 4 parts by mass of Tinuvin 109 (manufactured by Ciba Specialty Chemicals), chinuvin 171 (Ciba Specialty Chemicals Co., Ltd.) 5 parts by mass, the above-mentioned retardation control agent A is 10.0 parts by mass, retardation control agent B is 6.6 parts by mass, methylene chloride 94 parts by mass and ethanol 8 An additive solution 3 was prepared by adding parts by mass and stirring while heating.
43.5 parts by mass of the additive solution 3 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 28% at the start of stretching. A draw ratio was 18%, and a cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 14
[Preparation of cellulose acylate film A14]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate butyrate having an acetyl group substitution degree of 0.30 and a butyryl group substitution degree of 2.50 100 parts by weight Triphenyl phosphate 8.0 parts by weight Ethylphthalyl ethyl glycolate 4.0 parts by weight Methylene chloride 403 parts by weight Ethanol 60.3 parts by mass

Into another mixing tank, 12.9 parts by mass of the above-mentioned retardation control agent A, 7.1 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of ethanol are charged and heated. The additive solution 4 was prepared by stirring.
24.3 parts by mass of the additive solution 4 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring.
After casting on a band, it was peeled off, and stretched laterally with a tenter stretching machine at a residual solvent amount of 34% at the start of stretching. The draw ratio was 30%, and a cellulose acetate film (thickness: 70 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 15
[Preparation of cellulose acylate film A15]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.78 and an acetyl group substitution degree of 6-position / total substitution degree of 0.33 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass Here, the substitution degree of the acetyl group is (DS2 + DS3 + DS6) The 6-position substitution degree / total substitution degree of the acetyl group is (DS6 / (DS2 + DS3 + DS6)), and DS2, DS3, and DS6 are the 2nd, 3rd, and 6th glucose units constituting cellulose, respectively. The degree of substitution of the hydroxyl group at the position with an acyl group.

In another mixing tank, 13.1 parts by mass of retardation control agent A, 6.9 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating. A retardation controlling agent solution 08 was prepared.
17.4 parts by mass of the retardation control (raising) agent solution 01 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 2.3 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 1.2 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. The draw ratio was 28%, and a cellulose acetate film (thickness: 70 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 16
[Preparation of cellulose acylate film A16]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.75 and an acetyl group substitution degree of 6-position / total substitution degree of 0.35 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 12.0 parts by mass of retardation control agent A, 8.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating. A retardation controlling agent solution 09 was prepared.
The dope was prepared by mixing 474 parts by mass of the cellulose acetate solution with 9.9 parts by mass of the retardation controlling (raising) agent solution 01 and stirring sufficiently. The addition amount of retardation adjusting agent A was 1.2 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 0.8 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 30% at the start of stretching. The draw ratio was 30%, and a cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 17
[Preparation of cellulose acylate film A17]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.78 and an acetyl group substitution degree of 6-position / total substitution degree of 0.33 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 12.0 parts by mass of retardation control agent A, 8.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating. A retardation control agent solution 10 was prepared.
17.4 parts by mass of the retardation control (raising) agent solution 01 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 2.4 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 1.6 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 28% at the start of stretching. A draw ratio was 25%, and a cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 18
[Preparation of cellulose acylate film A18]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.75 and an acetyl group substitution degree of 6-position / total substitution degree of 0.35 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 10.7 parts by mass of retardation control agent A, 9.3 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating. A retardation control agent solution 11 was prepared.
14.8 parts by mass of the retardation control agent solution 11 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 1.6 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 1.4 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 31% at the start of stretching. A draw ratio was 20%, and a cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 19
[Production of Cellulose Acylate Film A19]
24.7 parts by mass of the retardation control (raising) agent solution 01 was mixed with 474 parts by mass of the cellulose acetate solution prepared in Example 1, and the dope was prepared by sufficiently stirring. The addition amount of the retardation adjusting agents A and B was 2.5 parts by mass with respect to 100 parts by mass of cellulose acetate.

  A cellulose acetate film (thickness: 110 μm) was produced in the same manner as in Example 1 except that the amount of residual solvent was 30% and the draw ratio was 25%. About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 20
[Creation of cellulose acylate film A20]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate propionate with a substitution degree of acetyl group of 1.90 and a substitution degree of propionyl group of 0.80 100 parts by weight Triphenyl phosphate 8.0 parts by weight Ethylphthalylethyl glycolate 4.0 parts by weight Methylene chloride 403 parts by weight 60.3 parts by mass of ethanol

Into another mixing tank, 12.0 parts by mass of the above-mentioned retardation control agent A, 8.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of ethanol were added and heated. The additive solution 5 was prepared by stirring.
24.7 parts by mass of the additive solution 5 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring.
After casting on a band, it was peeled off, and stretched laterally with a tenter stretching machine at a residual solvent amount of 34% at the start of stretching. A draw ratio was set to 21%, and a cellulose acetate film (thickness: 80 μm) was produced in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 21
[Creation of cellulose acylate film A21]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate propionate having an acetyl group substitution degree of 0.18 and a propionyl group substitution degree of 2.47 100 parts by weight Triphenyl phosphate 8.5 parts by weight Ethylphthalylethyl glycolate 2.0 parts by weight Methylene chloride 290 parts by weight 60 parts by mass of ethanol

In another mixing tank, 5 parts by mass of cellulose acetate propionate, 6 parts by mass of Tinuvin 326 (manufactured by Ciba Specialty Chemicals), 4 parts by mass of Tinuvin 109 (manufactured by Ciba Specialty Chemicals), chinuvin 171 (manufactured by Ciba Specialty Chemicals) 5 parts by mass, 11.6 parts by mass of the above-mentioned retardation control agent A, 5.0 parts by mass of retardation control agent B, 94 parts by mass of methylene chloride and ethanol 8 parts by mass was added and stirred while heating to prepare additive solution 6.
28.8 parts by mass of the additive solution 6 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 30% at the start of stretching. A draw ratio was 25%, and a cellulose acetate film (thickness: 70 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 22
[Preparation of cellulose acylate film A22]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate butyrate having a substitution degree of acetyl group of 1.40 and a substitution degree of butyryl group of 1.30 100 parts by weight Triphenyl phosphate 8.0 parts by weight Ethylphthalyl ethyl glycolate 4.0 parts by weight Methylene chloride 403 parts by weight Ethanol 60.3 parts by mass

In another mixing tank, 8.0 parts by mass of the above-mentioned retardation control agent A, 12.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of ethanol are charged and heated. The additive solution 7 was prepared by stirring.
The dope was prepared by mixing 19.8 parts by mass of the additive solution 7 with 474 parts by mass of the cellulose acetate solution and stirring sufficiently.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 28% at the start of stretching. The draw ratio was 28%, and a cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 23
[Preparation of cellulose acylate film A23]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate butyrate having an acetyl group substitution degree of 0.30 and a butyryl group substitution degree of 2.50 100 parts by weight Triphenyl phosphate 8.5 parts by weight Ethylphthalyl ethyl glycolate 2.0 parts by weight Methylene chloride 290 parts by weight Ethanol 60 parts by mass

In another mixing tank, 5 parts by mass of cellulose acetate butyrate, 6 parts by mass of Tinuvin 326 (manufactured by Ciba Specialty Chemicals), 4 parts by mass of Tinuvin 109 (manufactured by Ciba Specialty Chemicals), chinuvin 171 (Ciba Specialty Chemicals Co., Ltd.) 5 parts by mass, the above-mentioned retardation control agent A is 10.0 parts by mass, retardation control agent B is 6.6 parts by mass, methylene chloride 94 parts by mass and ethanol 8 An additive solution 8 was prepared by adding parts by mass and stirring while heating.
43.5 parts by mass of the additive solution 8 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. A draw ratio was 25%, and a cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 24
[Preparation of cellulose acylate film A24]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.78 and an acetyl group substitution degree of 6-position / total substitution degree of 0.33 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 12.0 parts by mass of retardation control agent A, 8.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating. A retardation controlling agent solution 12 was prepared.
24.7 parts by mass of the retardation control agent solution 12 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 3.0 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 2.0 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 28% at the start of stretching. A draw ratio was 23%, and a cellulose acetate film (thickness: 100 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 25
[Preparation of cellulose acylate film A25]
A cellulose acetate film (thickness: 100 μm) was prepared in the same manner as in Example 24 except that the stretching ratio was 26%.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 26
[Preparation of cellulose acylate film A26]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.75 and an acetyl group substitution degree of 6-position / total substitution degree of 0.35 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 10.0 parts by weight of retardation control agent A, 10.0 parts by weight of retardation control agent B, 87 parts by weight of methylene chloride and 13 parts by weight of methanol are added and stirred while heating. A retardation control agent solution 13 was prepared.
29.2 parts by mass of the retardation control agent solution 13 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 3.0 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 3.0 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off, and stretched laterally with a tenter stretching machine at a residual solvent amount of 34% at the start of stretching. The draw ratio was 32%, and a cellulose acetate film (thickness: 80 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 27
[Preparation of cellulose acylate film A27]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
Cellulose acetate having an acetyl group substitution degree of 2.82 and an acetyl group substitution degree of 6-position / total substitution degree of 0.32 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 10.0 parts by weight of retardation control agent A, 10.0 parts by weight of retardation control agent B, 87 parts by weight of methylene chloride and 13 parts by weight of methanol are added and stirred while heating. A retardation controlling agent solution 14 was prepared.
A dope was prepared by mixing 31.1 parts by mass of the retardation controlling agent solution 14 with 474 parts by mass of the cellulose acetate solution and stirring sufficiently. The addition amount of retardation adjusting agent A was 3.8 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 2.5 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 30% at the start of stretching. A draw ratio was 25%, and a cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 28
[Preparation of cellulose acylate film A27]
Each component of the following cellulose acetate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

(Cellulose acetate solution composition)
3. Cellulose acetate having an acetyl group substitution degree of 2.80 and an acetyl group substitution degree of 6-position / total substitution degree of 0.32 100 parts by weight Triphenyl phosphate (plasticizer) 8.0 parts by weight Biphenyl diphenyl phosphate (plasticizer) 0 parts by mass Methylene chloride (first solvent) 403 parts by mass Methanol (second solvent) 60.2 parts by mass Silica (particle size 0.2 μm) 0.1 parts by mass

In another mixing tank, 14.0 parts by mass of retardation control agent A, 6.0 parts by mass of retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating. A retardation controlling agent solution 15 was prepared.
34.6 parts by mass of the retardation control agent solution 15 was mixed with 474 parts by mass of the cellulose acetate solution, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 4.6 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent B was 2.0 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. A draw ratio was 20%, and a cellulose acetate film (thickness: 60 μm) was prepared in the same manner as in Example 1.

  About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 1
[Preparation of cellulose acylate film B1]
Into the mixing tank, 20 parts by mass of the above-mentioned retardation control agent A, 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and stirred while heating to prepare a retardation control agent solution 08.
The dope was prepared by mixing 36.2 parts by mass of the retardation control (raising) solution 08 with 474 parts by mass of the cellulose acetate solution of Example 1 and stirring sufficiently. The addition amount of the retardation control agent A was 6 parts by mass with respect to 100 parts by mass of cellulose acetate.

After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 28% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 93 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 2
[Preparation of cellulose acylate film B2]
A dope was prepared by mixing 45.2 parts by mass of the retardation control (raising) solution 08 with 474 parts by mass of the cellulose acetate solution of Example 1 and stirring sufficiently. The addition amount of the retardation adjusting agent A was 7.5 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 26% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 90 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 3
[Preparation of cellulose acylate film B3]
A cellulose acetate film (thickness: 89 μm) was produced in the same manner as in Comparative Example 2 except that the draw ratio was 30%.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 4
[Preparation of cellulose acylate film B4]
64.3 parts by mass of the retardation control (raising) solution 08 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of the retardation adjusting agent A was 10 parts by mass with respect to 100 parts by mass of cellulose acetate.
As the film was cast on a band, a whiteish crystalline compound was deposited on the surface of the film as it was dried.

Comparative Example 5
[Preparation of cellulose acylate film B5]
Into the mixing tank, 20 parts by mass of the above-mentioned retardation control agent B, 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and stirred while heating to prepare a retardation control agent solution 09.
The dope was prepared by mixing 12.1 parts by mass of the retardation control (raising) agent solution 09 with 474 parts by mass of the cellulose acetate solution of Example 1 and stirring sufficiently. The addition amount of the retardation adjusting agent B was 2 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 32% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 92 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 6
[Preparation of cellulose acylate film B6]
A cellulose acetate film (thickness: 90 μm) was produced in the same manner as in Comparative Example 5 except that the draw ratio was 30%. About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 7
[Preparation of cellulose acylate film B7]
36.2 parts by mass of retardation control (raising) solution 09 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of the retardation adjusting agent B was 6 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off, and stretched laterally with a tenter stretching machine at a residual solvent amount of 34% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 93 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 8
[Preparation of cellulose acylate film B8]
A cellulose acetate film (thickness: 91 μm) was produced in the same manner as in Comparative Example 7 except that the draw ratio was 30%. About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 9
[Preparation of cellulose acylate film B9]
Into the mixing tank, 10 parts by mass of the above-mentioned retardation control agent A, 10 parts by mass of retardation control agent C, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating to control retardation. Agent solution 10 was prepared.
45.2 parts by mass of the retardation control (raising) solution 10 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of retardation adjusting agent A was 3.75 parts by mass with respect to 100 parts by mass of cellulose acetate, and the addition amount of retardation adjusting agent C was 3.75 parts by mass with respect to 100 parts by mass of cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 28% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 91 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Comparative Example 10
[Preparation of cellulose acylate film B10]
Into the mixing tank, 10 parts by mass of the above-mentioned retardation control agent B, 10 parts by mass of retardation control agent D, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating to control the retardation. Agent solution 11 was prepared.
36.2 parts by mass of the retardation control (raising) solution 10 was mixed with 474 parts by mass of the cellulose acetate solution of Example 1, and the dope was prepared by sufficiently stirring. The addition amount of the retardation adjusting agent B was 3 parts by mass with respect to 100 parts by mass of the cellulose acetate, and the addition amount of the retardation adjusting agent D was 3 parts by mass with respect to 100 parts by mass of the cellulose acetate.
After casting on a band, it was peeled off and transversely stretched with a tenter stretching machine at a residual solvent amount of 33% at the start of stretching. The draw ratio was 26%, and a cellulose acetate film (thickness: 92 μm) was prepared in the same manner as in Example 1.
About the produced cellulose acetate film, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA (21ADH, Oji Scientific Instruments Co., Ltd. product). Further, the wavelength dispersion shape, the humidity dependence of the optical performance at 25 ° C., the moisture permeability, and the dimensional change rate were measured. The results are shown in Table 1.

Example 29
[Production of Polarizing Plates A1 to A28]
A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film.
The produced cellulose acylate film 1 was subjected to saponification treatment and attached to one side of a polarizing film using a polyvinyl alcohol-based adhesive. The saponification treatment was performed under the following conditions.
A 1.5N aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.01 N dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The produced cellulose acylate film A1 was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the above-mentioned dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C.
Table 2 shows the results obtained by measuring the surface energy of the saponified cellulose acetate film.
A commercially available cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) is subjected to the same saponification treatment, and a polarizing film is formed on the side opposite to the prepared cellulose acetate film A1 using a polyvinyl alcohol adhesive. Pasted.

The transmission axis of the polarizing film and the slow axis of the prepared cellulose acetate film were arranged in parallel. Further, the transmission axis of the polarizing film and the slow axis of the commercially available cellulose triacetate film were arranged so as to be orthogonal to each other.
In this way, a polarizing plate A1 was produced. Similarly, polarizing plates A2 to A28 using cellulose acylate films A2 to A28 were produced. Table 2 shows the results obtained by measuring the surface energy of the cellulose acylate films A2 to A28 after the saponification treatment.
After measuring the optical performance (single-plate transmittance, polarization degree) of the produced polarizing plate with Shimadzu's own spectrophotometer UV3100, the polarizing plate is allowed to stand in a constant temperature and humidity chamber at 60 ° C. and 90% RH for 500 hours. Aged. The optical performance of the cellulose acetate film after aging was measured in the same manner to determine the change in the degree of polarization. The results are shown in Table 3.

Comparative Example 11
[Production of Polarizing Plates B1 to B10]
In the same manner as in Example 29, polarizing plates B1 to B10 using cellulose acylate films B1 to B10 were produced. Table 2 shows the results obtained by measuring the surface energy of the cellulose acylate films B1 to B10 after the saponification treatment.
Table 3 shows values of the degree of polarization change obtained in the same manner as in Example 12.

Example 30
[Production and Evaluation of Polarizing Plate C1 and Liquid Crystal Display]
(Preparation of coating solution for light scattering layer)
50 g of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (PETA, Nippon Kayaku Co., Ltd.) was diluted with 38.5 g of toluene. Furthermore, 2 g of a polymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) was added and mixed and stirred. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet rays was 1.51.

Further, a 30% toluene dispersion of crosslinked polystyrene particles having an average particle size of 3.5 μm (refractive index: 1.60, SX-350, manufactured by Soken Chemical Co., Ltd.) dispersed in this solution for 20 minutes at 10,000 rpm with a Polytron disperser. Add 13.3 g of 30% toluene dispersion of 1.7 g and crosslinked acrylic-styrene particles having an average particle size of 3.5 μm (refractive index 1.55, manufactured by Soken Chemical Co., Ltd.), and finally, fluorine-based surface modification 0.75 g of agent (FP-1) and 10 g of silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.) were added to obtain a finished solution.
The liquid mixture was filtered through a polypropylene filter having a pore size of 30 μm to prepare a light scattering layer coating solution.

(Preparation of coating solution for low refractive index layer)
Thermally crosslinkable fluorine-containing polymer having a refractive index of 1.42 (JN-7228, solid content concentration 6%, manufactured by JSR Corporation) 13 g, silica sol (silica, MEK-ST particle size difference, average particle size 45 nm, solid content 30% concentration, manufactured by Nissan Chemical Co., Ltd.) 1.3 g, 0.6 g of sol solution a, 5 g of methyl ethyl ketone, and 0.6 g of cyclohexano were added. After stirring, the mixture was filtered through a polypropylene filter having a pore size of 1 μm, and low refraction A coating solution for the rate layer was prepared.

(Preparation of transparent protective film 01 with antireflection layer)
An 80 μm-thick triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.) is unwound in a roll form, and the coating liquid for the functional layer (light scattering layer) is 180 lines / inch, Using a gravure pattern with a depth of 40 μm and a microgravure roll with a diameter of 50 mm and a doctor blade, it was applied at a gravure roll rotation speed of 30 rpm and a conveyance speed of 30 m / min, dried at 60 ° C. for 150 seconds, and further purged with nitrogen Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 160 W / cm, the coating layer is cured by irradiating with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ^2. A layer was formed and wound up.
The triacetylcellulose film coated with the functional layer (light scattering layer) was unwound again, and the prepared coating solution for low refractive index layer had a gravure pattern with a number of lines of 180 lines / inch and a depth of 40 μm and a diameter of 50 mm. Using a micro gravure roll and a doctor blade, it was applied under the conditions of a gravure roll rotation speed of 30 rpm and a conveyance speed of 15 m / min, dried at 120 ° C. for 150 seconds, further dried at 140 ° C. for 8 minutes and then purged with nitrogen Using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.), an ultraviolet ray with an illuminance of 400 mW / cm ² and an irradiation amount of 900 mJ / cm ² was irradiated to form a low refractive index layer with a thickness of 100 nm, Winded up.

(Preparation of polarizing plate C1)
A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film.
The produced transparent protective film 01 with an antireflection layer was subjected to the same saponification treatment as in Example 29, and was attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive.
The cellulose acetate film A1 produced in Example 1 was subjected to the same saponification treatment as in Example 29, and was attached to the opposite side of the polarizing film using a polyvinyl alcohol-based adhesive.

The transmission axis of the polarizing film and the slow axis of the cellulose acetate film prepared in Example 1 were arranged in parallel. The transmission axis of the polarizing film and the slow axis of the commercially available cellulose triacetate film were arranged so as to be orthogonal to each other. Thus, a polarizing plate C1 was produced.
Using a spectrophotometer (manufactured by JASCO Corporation), spectral reflectance at an incident angle of 5 ° was measured in a wavelength region of 380 to 780 nm, and an integrating sphere average reflectance of 450 to 650 nm was obtained. 3%.
Polarizing plates C2 to C18 were similarly produced from the cellulose triacetate films prepared in Examples 2 to 18 instead of Example 1.

Example 31
(Preparation of coating solution for hard coat layer)
750.0 parts by weight of trimethylolpropane triacrylate (TMPTA, Nippon Kayaku Co., Ltd.), 270.0 parts by weight of poly (glycidyl methacrylate) having a weight average molecular weight of 3000, 730.0 g of methyl ethyl ketone, 500.0 g of cyclohexanone and light A polymerization initiator (Irgacure 184, manufactured by Nippon Ciba-Geigy Co., Ltd.) 50.0 g was added and stirred. The solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for a hard coat layer.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129, manufactured by Ishihara Sangyo Co., Ltd.) containing cobalt and surface-treated with aluminum hydroxide and zirconium hydroxide were used.
The following dispersant (38.6 g) and cyclohexanone (704.3 g) were added to 257.1 g of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a weight average diameter of 70 nm.

(Preparation of coating solution for medium refractive index layer)
To 88.9 g of the above titanium dioxide dispersion, 58.4 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA), 3.1 g of a photopolymerization initiator (Irgacure 907), a photosensitizer (Kayacure- DETX, manufactured by Nippon Kayaku Co., Ltd.) 1.1 g, methyl ethyl ketone 482.4 g and cyclohexanone 1869.8 g were added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
To 56.8 g of the above titanium dioxide dispersion, 47.9 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907, Nippon Ciba Geigy ( 4.0 g), photosensitizer (Kayacure-DETX, Nippon Kayaku Co., Ltd.) 1.3 g, methyl ethyl ketone 455.8 g, and cyclohexanone 1427.8 g were added and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
The copolymer (P-1) according to the present invention is dissolved in methyl isobutyl ketone so as to have a concentration of 7% by mass, and a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) is solidified. 3% with respect to the content and 5% by mass of the photo radical generator Irgacure 907 (trade name) with respect to the solid content to prepare a coating solution for the low refractive index layer.

(Preparation of transparent protective film 02 with antireflection layer)
A hard coat layer coating solution was applied onto a triacetyl cellulose film (TD-80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ² , the coating layer was cured by irradiating with an irradiation amount of 300 mJ / cm ² to form a hard coat layer having a thickness of 8 μm.
On the hard coat layer, a medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution were successively applied using a gravure coater having three coating stations.

The intermediate refractive index layer was dried at 100 ° C. for 2 minutes, and the ultraviolet curing condition was 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 400 mW / cm ² and the irradiation dose was 400 mJ / cm ² . The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 67 nm.

The drying conditions of the high refractive index layer and the low refractive index layer are both 90 ° C., 1 minute, 100 ° C., 1 minute, and the ultraviolet curing conditions are nitrogen so that the oxygen concentration is 1.0 volume% or less While purging, a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) was used to obtain an irradiation dose of 600 mW / cm ² and an irradiation dose of 600 mJ / cm ² .
The cured high refractive index layer had a refractive index of 1.905 and a film thickness of 107 nm, and the low refractive index layer had a refractive index of 1.440 and a film thickness of 85 nm. In this way, a transparent protective film 02 with an antireflection layer was produced.

(Preparation of polarizing plate D1)
A polarizing plate D1 was produced in the same manner as in Example 30, except that the transparent protective film 02 with antireflection layer was used instead of the transparent protective film 01 with antireflection layer.
Using a spectrophotometer (manufactured by JASCO Corporation), the spectral reflectance at an incident angle of 5 ° was measured in the wavelength region of 380 to 780 nm, and the integrating sphere average reflectance of 450 to 650 nm was determined to be 0. 4%.
Polarizing plates D2 to D18 were prepared in the same manner from the cellulose triacetate films prepared in Examples 2 to 18 instead of Example 1.

Comparative Example 12
(Preparation of polarizing plate E1)
A polarizing plate was produced in the same manner as in Example 30 except that the cellulose acetate film B1 produced in Comparative Example 1 was used instead of the cellulose acetate film A1 produced in Example 1. Further, polarizing plates E2 to E10 were similarly prepared using the cellulose acetate films prepared in Comparative Examples 2 to 10.

Comparative Example 13
(Preparation of polarizing plate F1)
A polarizing plate was produced in the same manner as in Example 31 except that the cellulose acetate film B1 produced in Comparative Example 1 was used instead of the cellulose acetate film A1 produced in Example 1. Further, polarizing plates F2 to F10 were similarly produced using the cellulose acetate film produced in Comparative Examples 2 to 10.

Example 32
The optical compensation sheet prepared in Example 1 was used instead of the pair of polarizing plates and the pair of optical compensation sheets provided in the liquid crystal display device (manufactured by Fujitsu Limited) using the vertical alignment type liquid crystal cell. The polarizing plate produced in Example 29 was attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film produced in Example 1 was on the liquid crystal cell 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.
As a result of observing the manufactured liquid crystal display device, a neutral black display was realized in the front direction and the viewing angle direction. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range).
As shown in Table 4 below, a wide viewing angle was realized by providing the polarizing plate of the present invention.
Similar results were obtained when the polarizing plates prepared using the optical compensation sheets prepared in Examples 2 to 18 were used.

Example 33
Instead of a pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell, the optical compensation sheet produced in Example 1 was used, The polarizing plate obtained in Example 30 was attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film produced in Example 1 was on the liquid crystal cell 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.
As a result of observing the manufactured liquid crystal display device, a neutral black display was realized in the front direction and the viewing angle direction. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range).
As shown in Table 4 below, a wide viewing angle was realized by providing the polarizing plate of the present invention.
Similar results were obtained when the polarizing plates prepared using the optical compensation sheets prepared in Examples 2 to 18 were used.

Example 34
Instead of a pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell, the optical compensation sheet produced in Example 1 was used, The polarizing plate prepared in Example 31 was attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film prepared in Example 1 was on the liquid crystal cell 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.
As a result of observing the manufactured liquid crystal display device, a neutral black display was realized in the front direction and the viewing angle direction. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range).
As shown in Table 4 below, a wide viewing angle was realized by providing the polarizing plate of the present invention.
Similar results were obtained when the polarizing plates prepared using the optical compensation sheets prepared in Examples 2 to 18 were used.

Example 35
Instead of a pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell, the optical compensation sheet produced in Example 19 was used, One polarizing plate produced in Example 29 was attached to the backlight side through an adhesive so that the cellulose acetate film produced in Example 19 was on the liquid crystal cell side. One commercially available polarizing plate (HLC2-5618, manufactured by Sanlitz) without a viewing angle compensator was attached to the polarizing plate on the observer 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.
As a result of observing the manufactured liquid crystal display device, a neutral black display was realized in the front direction and the viewing angle direction. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range).
As shown in Table 4 below, a wide viewing angle was realized by providing the polarizing plate of the present invention.
Similar results were obtained when the polarizing plate prepared using the optical compensation sheet prepared in Examples 20 to 28 was used.

Comparative Example 14
About a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell, from a black display (L1) to a white display (L8) using a measuring device (EZ-Contrast160D, manufactured by ELDIM). The viewing angle was measured in 8 stages. The results are shown in Table 4. It can be seen that the viewing angle is narrower than when the polarizing plate of the present invention is used.

Comparative Example 15
Comparison was made using the cellulose acetate film prepared in Comparative Example 1 instead of the pair of polarizing plates and the pair of optical compensation sheets provided in the liquid crystal display device (manufactured by Fujitsu Limited) using the vertical alignment type liquid crystal cell. The polarizing plate produced in Example 11 was attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film produced in Comparative Example 1 was on the liquid crystal cell 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.
As a result of observing the produced liquid crystal display device, black display was realized in the front direction, but the viewing angle direction was inferior to the present invention. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range). The results are shown in Table 4. It can be seen that the viewing angle is narrower than when the polarizing plate of the present invention is used.
Even when the polarizing plates produced in Comparative Examples 2 to 10 were used, it was found that the viewing angle was narrower than when the polarizing plate of the present invention was used.

Comparative Example 16
Comparison was made using the cellulose acetate film prepared in Comparative Example 1 instead of the pair of polarizing plates and the pair of optical compensation sheets provided in the liquid crystal display device (manufactured by Fujitsu Limited) using the vertical alignment type liquid crystal cell. The polarizing plate produced in Example 12 was attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film produced in Comparative Example 1 was on the liquid crystal cell 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.
As a result of observing the manufactured liquid crystal display device, a neutral black display was realized in the front direction, but the viewing angle direction was inferior to the present invention. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range). The results are shown in Table 4. It can be seen that the viewing angle is narrower than when the polarizing plate of the present invention is used.
Even when the polarizing plates produced in Comparative Examples 2 to 10 were used, it was found that the viewing angle was narrower than when the polarizing plate of the present invention was used.

Comparative Example 17
Comparison was made using the cellulose acetate film prepared in Comparative Example 1 instead of the pair of polarizing plates and the pair of optical compensation sheets provided in the liquid crystal display device (manufactured by Fujitsu Limited) using the vertical alignment type liquid crystal cell. The polarizing plate produced in Example 13 was attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film produced in Comparative Example 1 was on the liquid crystal cell 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.
As a result of observing the manufactured liquid crystal display device, a neutral black display was realized in the front direction, but the viewing angle direction was inferior to the present invention. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range). The results are shown in Table 4. It can be seen that the viewing angle is narrower than when the polarizing plate of the present invention is used.
Even when the polarizing plates produced in Comparative Examples 2 to 10 were used, it was found that the viewing angle was narrower than when the polarizing plate of the present invention was used.

Comparative Example 18
A liquid crystal display layer was produced in the same manner as in Example 35 except that the cellulose acetate film produced in Comparative Example 8 was used instead of the cellulose acetate film produced in Example 19. As a result of observing the manufactured liquid crystal display device, neutral black display was realized in the front direction, but inferior to the present invention in the viewing angle direction. In addition, using a measuring instrument (EZ-Contrast 160D, manufactured by ELDIM), the viewing angle (contrast ratio is 10 or more and there is no black-side gradation inversion) in eight stages from black display (L1) to white display (L8). Range). The results are shown in Table 4. It can be seen that the viewing angle is narrower than when the polarizing plate of the present invention is used.

Example 36
(Preparation of OCB type (bend alignment) liquid crystal cell)
A polyimide film was provided as an alignment film on a glass substrate with a TFT electrode, and the alignment film was rubbed. The obtained two glass substrates are opposed to each other so that the rubbing directions are parallel to each other, and a fluorine-based liquid crystal compound (property values are Δn = 0.16, Δε = 9.9) in a cell gap (gap between the two glass substrates). 3, k11 = 13.4 pN, k22 = 7.4 pN, k33 = 14.7 pN) to produce a bend alignment liquid crystal cell.
(Preparation of optical retardation compensation film)
On the cellulose acetate film A1 prepared in Example 1, an alignment film coating solution having the following composition was applied at 28 ml / m ² with a # 16 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 slow axis of cellulose acetate film (measured at a wavelength of 632.8 nm).

  On the obtained alignment film, the following discotic liquid crystal TE-1 and ethylene oxide modified trimethylolpropane triacrylate (V # 360, manufactured by Osaka Organic Chemical Co., Ltd.) were mixed at a mass ratio of 9: 1 to methyl ethyl ketone. Was added to prepare a 10% by mass solution as a whole. The obtained solution was applied by spin coating at 2000 rpm, heated to 145 ° C. and heat-treated. Thereafter, it was cooled to room temperature to form a (discotic) liquid crystal layer having a thickness of 1.4 μm. The Re retardation value of the optically anisotropic layer measured at a wavelength of 546 nm was 30 nm. The angle between the disc surface and the support (cellulose acetate film) surface was 36 ° on average. Thus, an optical retardation compensation film was produced.

  A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film. Using a polyvinyl alcohol adhesive, apply the cellulose acetate film side of the optical retardation compensation film to one side of the polarizing film so that the slow axis of the cellulose acetate film is parallel to the transmission axis of the polarizing film. I attached. A commercially available cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was subjected to saponification treatment and attached to the opposite side of the polarizing film using a polyvinyl alcohol-based adhesive. In this way, a polarizing plate was produced.

  Two produced polarizing plates were attached so as to sandwich the obtained 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. A rectangular wave voltage of 55 Hz was applied to the liquid crystal cell. A normally white mode of 2V white display and 5V black display was set. Using the measurement ratio (EZ-Contrast160D, manufactured by ELDIM) as the contrast ratio of the transmittance ratio (white display / black display), the viewing angle can be adjusted in eight steps from black display (L1) to white display (L8). It was measured. The results are shown in Table 6.

Comparative Example 18
In the same manner as in Example 36, commercially available cellulose acetate film (Fuji Tac TD80, manufactured by Fuji Photo Film Co., Ltd.), surface treatment, coating of alignment film and liquid crystal molecules, preparation of polarizing plate, OCB type liquid crystal device Fabrication was performed. Table 6 shows the results of measuring the viewing angle of the manufactured liquid crystal display device.

(Evaluation of liquid crystal display devices)
The results of viewing angle characteristics of the liquid crystal display devices manufactured in Example 36 and Comparative Example 18 are shown below.

The liquid crystal display device produced in Example 36 obtained a wide viewing angle as compared with the liquid crystal display device produced in Comparative Example 18.
Further, in Example 36, when the cellulose acetate film produced in Examples 2 to 18 was used instead of the cellulose acetate film produced in Example 1, a wide viewing angle was obtained in the same manner.

Claims (24)

Cellulose acylate, at least one of 0.01 to 20 parts by mass of the compound represented by the following general formula (I) with respect to 100 parts by mass of cellulose acylate, and at least 3 parts with respect to 100 parts by mass of cellulose acylate An optical compensation sheet comprising 0.01 to 20 parts by mass of a cyclic compound having a substituent.

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ each independently represents a hydrogen atom or a substituent, and R ¹ , R ² , R ³ , R ⁴ and R ⁵ each represents an electron donating group, R ⁸ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkynyl group having 2 to 6 carbon atoms. Group, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, cyano Represents a group or a halogen atom.)   The optical compensation sheet according to claim 1, wherein the Re retardation value is 20 to 200 nm, and the Rth retardation value is 70 to 400 nm.   3. The optical compensation sheet according to claim 1, wherein the Re retardation value is 20 to 70 nm and the Rth retardation value is 70 to 400 nm.   The optical compensation sheet according to any one of claims 1 to 3, wherein a ratio (Re / Rth ratio) between the Re retardation value and the Rth retardation value is 0.1 to 0.8.   The optical compensation sheet according to any one of claims 1 to 4, wherein the optical compensation sheet comprises only one cellulose acylate film having a film thickness of 20 µm to 160 µm.   6. The difference (Re700-Re400) between the Re retardation value at 700 nm (Re700) and the Re retardation value at 400 nm (Re400) is from -25 nm to 10 nm. The optical compensation sheet according to item.   7. The difference between the Rth retardation value at 700 nm (Rth700) and the Rth retardation value at 400 nm (Rth400) (Rth700-Rth400) is -50 nm to 20 nm. The optical compensation sheet according to item.   Differences in Re retardation value, Rth retardation value measured under 25 ° C. and 10% RH environment, and Re retardation value and Rth retardation value measured under 25 ° C. and 80% RH environment are within 25 nm and 70 nm, respectively. The optical compensation sheet according to claim 1, wherein the optical compensation sheet is provided. 9. The optical compensation sheet according to claim 1, wherein moisture permeability at 25 ° C. and 90% RH is 20 g / m ² · 24 hr to 250 g / m ² · 24 hr.   The optical compensation sheet according to any one of claims 1 to 9, wherein a dimensional change under dry conditions at 90 ° C is within -0.15%.   The optical compensation sheet according to any one of claims 1 to 10, wherein a dimensional change at 60 ° C and 90% RH is within -0.15%.   The optical compensation sheet according to any one of claims 1 to 11, wherein the optical compensation sheet is made of a cellulose acetate film having a surface energy of 55 to 75 mN / m.   The optical device according to any one of claims 1 to 12, wherein when used as a polarizing plate protective film, a decrease in the degree of polarization after aging for 500 hours in an atmosphere of 60 ° C and 95% RH is within 3%. Compensation sheet.   The optical compensation sheet according to claim 1, comprising a cellulose acylate film stretched at a stretch ratio of 3 to 100%.   The cellulose acylate is cellulose acetate having an acetylation degree of 59.0 to 61.5%, and a Re / Rth change amount per 1% of draw ratio is 0.01 to 0.1. The optical compensation sheet according to any one of claims 1 to 14.   The film is stretched in a direction perpendicular to the longitudinal direction while being conveyed in the longitudinal direction, the residual solvent amount of the cellulose acylate film at the start of stretching is 2% to 50%, and the slow axis of the film is the length of the film The optical compensation sheet according to claim 1, wherein the optical compensation sheet is in a direction perpendicular to the scale direction. The cellulose acylate film is composed of cellulose acylate in which the hydroxyl group of cellulose is substituted with an acetyl group and an acyl group having 3 to 22 carbon atoms, and the substitution degree A and the number of carbon atoms of the acetyl group of the cellulose acylate are The optical compensation sheet according to any one of claims 1 to 16, wherein the substitution degree B of the acyl group of 3 to 22 satisfies the following formulas (VI) and (VII).
Formula (VI): 2.0 ≦ A + B ≦ 3.0
Formula (VII): 0 <B   The optical compensation sheet according to claim 17, wherein the acyl group having 3 to 22 carbon atoms is a butanoyl group or a propionyl group. A film made of cellulose acylate obtained by substituting the hydroxyl group of glucose unit constituting cellulose with an acyl group having 2 or more carbon atoms, and depending on the acyl group of the hydroxyl group at the 2-position of glucose unit constituting cellulose Cellulose acylate film satisfying the following formulas (XII) and (XIII) when the substitution degree is DS2, the substitution degree of the hydroxyl group at the 3-position is DS3, and the substitution degree of the hydroxyl group at the 6-position is DS6 The optical compensation sheet according to claim 1, wherein
Formula (XII): 2.0 ≦ DS2 + DS3 + DS6 ≦ 3.0
Formula (XIII): DS6 / (DS2 + DS3 + DS6) ≧ 0.315 The optical compensation sheet according to any one of claims 1 to 16, wherein the cellulose acylate is cellulose acetate . 2. The optical compensation sheet according to claim 1, wherein the cyclic compound having at least three substituents is a compound represented by the general formula (II).

(Wherein, X ¹ is a single bond, -NR ⁴ -, - O-or -S- were tables,; X ² represents a single bond, -NR ⁵ -, - O-or -S- were table ,; X ³ represents a single bond, -NR ⁶ -, - Represents O- or -S-,; R ^1, R ² and R ³ are each independently an alkyl group, an alkenyl group, an aryl group or a heterocyclic the ring was tables; and, R ^4, R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group, an alkenyl group, table to an aryl group or a heterocyclic group).   A polarizing plate comprising a polarizing film and two transparent protective films disposed on both sides thereof, wherein at least one of the transparent protective films is the optical compensation sheet according to any one of claims 1 to 21. A polarizing plate characterized by.   23. The antireflection layer having a specular reflectance of 2.5% or less comprising at least a light scattering layer and a low refractive index layer is provided on the transparent protective film opposite to the optical compensation sheet. Polarizer. The transparent protective film on the side opposite to the optical compensation sheet is provided with an antireflection layer having a specular reflectance of 0.5% or less in which at least a medium refractive index layer, a high refractive index layer, and a low refractive index layer are laminated in this order. 24. The polarizing plate according to claim 22 or 23.