JP2003128838A - Cellulose acylate dope solution and method for producing cellulose acylate film using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cellulose acylate film having a good surface condition and excellent in film strength by easily peeling the cellulose acylate film from a support in a production process for obtaining a good cellulose acylate film by preparing a solution in which a cellulose acylate is dissolved in an organic solvent in a stable condition. SOLUTION: The cellulose acylate solution comprises a dope solution in which the cellulose acylate is dissolved in the solution comprising the organic solvent, wherein a crosslinking agent having two or more groups that react with at least one active hydrogen is contained in 0.1-10 mass% relative to the cellulose acylate. A method for producing the cellulose acylate film using the cellulose acylate solution is provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cellulose acylate film useful for a silver halide photographic light-sensitive material or a protective film for a polarizing plate of a liquid crystal image display device, a method for producing the cellulose acylate film, and a method for producing the same. The present invention relates to a cellulose acylate dope solution.

[0002]

2. Description of the Related Art Conventionally, an organic solvent of a cellulose acylate dope solution used in producing a cellulose acylate film used in a protective film for a polarizing plate of a silver halide photographic light-sensitive material or a liquid crystal image display device is Chlorine-containing hydrocarbons such as dichloromethane have been used. Dichloromethane (boiling point: about 40 ° C.) has been conventionally used as a good solvent for cellulose acylate, and is preferably used because it has a low boiling point in the film-forming and drying steps of the manufacturing process and is easily dried. In recent years, chlorine-based organic solvents, which have a low boiling point from the viewpoint of environmental protection, have significantly reduced leakage in the handling process even in closed equipment. For example, a thorough closed system was used to prevent leakage from the system, and in the unlikely event of a leak, a gas absorption tower was installed before advancing to the outside air, and an organic solvent was adsorbed and treated. Furthermore, although the organic solvent is almost never discharged due to combustion by thermal power or decomposition of the chlorine-based organic solvent by an electron beam before discharging, further research is required until complete non-emission. On the other hand, a search for a solvent for cellulose acylate other than dichloromethane, which has been preferably used as a chlorine-based organic solvent, has been made. Known organic solvents exhibiting solubility in cellulose acylate, particularly cellulose triester, include acetone (boiling point 56 ° C.), methyl acetate (boiling point 56 ° C.), tetrahydrofuran (boiling point 65 ° C.), 1,3-dioxolane. (Boiling point 75 ° C), 1,4-dioxane (boiling point 101 ° C)
and so on. However, these organic solvents have not been sufficiently soluble in practical use by conventional dissolution methods.

As a solution to this problem, J. M. G. Cowie
Et al., Makromol. chem. 143, page 105 (1971), cellulose triacetate (degree of acetylation 60.1% to 61.3%) in acetone at -80
It is reported that a dilute solution of 0.5 to 5 mass% can be obtained by heating after cooling from ℃ to -70 ℃. A method of dissolving cellulose acylate at such a low temperature is called a cooling dissolution method. In addition, Kenji Uede et al. Describes spinning technology using a cooling dissolution method in "Dry spinning from acetone solution of cellulose triacetate" in Textile Machinery Society, Vol. 34, pp. 57-61 (1981). There is. In addition, JP-A-9-95538 and JP-A-9-9554.
In Japanese Patent No. 4 and Japanese Patent Publication No. 9-95557, against the background of the above technology, it is disclosed that a cellulose acylate is dissolved by a cooling dissolution method using a non-chlorine organic solvent. The non-chlorine organic solvent used at that time is an organic solvent selected from ethers, ketones or esters, and in particular, a film is produced by dissolving the cellulose acylate by the cooling dissolution method. Acetone, 2-methoxyethyl acetate, cyclohexanone, ethyl formate, methyl acetate, etc. are preferred as these specific organic solvents. However, even if these solvents are used, the conventional casting method is still insufficient for high-speed casting to obtain a cellulose acylate film.

On the other hand, the cellulose acylate film is
Generally, it is manufactured by a solvent cast method or a melt cast method. In the solvent cast method, a solution (dope) in which cellulose acylate is dissolved in a solvent is cast on a support and the solvent is evaporated to form a film. In the melt casting method, cellulose acylate melted by heating is cast on a support, and the support is cooled to form a film. The solvent cast method can produce a good film having higher flatness than the melt cast method. For this reason, the solvent cast method is more commonly used in practice.
In the recent solvent cast method, the problem is to improve the productivity of the film-forming process by shortening the time required from casting the dope onto the support to peeling the molding film on the support. Has become. In particular, when a cellulose acylate film is obtained by the solvent casting method, in the case of a cellulose acylate solution which is dissolved at room temperature, high temperature or by cooling using the above-mentioned non-chlorine organic solvent, peeling of the cellulose acylate film from its support is carried out. The problem is that it is difficult to remove. Further, it is required to increase productivity in response to the recent increase in demand for cellulose acylate film, and therefore high-speed casting is earnestly desired. From this viewpoint as well, the cellulose acylate film produced by the solution using a non-chlorine organic solvent was inferior in the high-speed casting property.

In this method, cellulose acylate is cast on a band or a drum, which is a metal support, and dried or cooled to give a gel film having high strength. The gel film is peeled from the support while containing an organic solvent. This is because it is difficult to peel the cellulose acylate film from the support during the subsequent step of being sufficiently dried. It was also found in the chlorine-based organic solvent of dichloromethane, and its improvement was desired as described above. As one method of this improvement, Japanese Patent Laid-Open No. 10-3
In 16701, the acid dissociation index pKa is 1.93 to 4.50.
[Preferably 2.0 to 4.4, more preferably 2.2.
~ 4.3 (e.g., 2.5-4.0), especially 2.6-
It is described that an acid of about 4.3 (for example, 2.6 to 4.0) or a salt thereof is preferable as the stripping agent. However, as a drawback, it causes a problem that a fine salt is formed with the alkaline earth metal contained in the cellulose acylate in the cellulose acylate solution and adheres to the system in a long casting process. There was a hope for its improvement.

[0006]

However, while it has been found that some solutions with these stripping agents significantly improve stripping, they were unsatisfactory. In particular, in the production of a cellulose acylate film by a so-called drum method in which it is peeled from the support and dried while being undried,
It was expected that the strippability at the time of stripping would be improved. Therefore, when preparing a solution of cellulose acylate in an organic solvent, it is possible to solve the problem that peeling from the (temporary) support is difficult due to drying after casting, and not only excellent peeling but also good surface condition There has been a demand for a method for producing the above cellulose acylate film. Further, it is possible to significantly improve the film strength of the produced cellulose acylate film, and even when the casting speed is high, a cellulose acylate solution that is peeled off and has good surface condition and film strength is formed, and thus excellent cellulose is obtained. A method for producing an acylate film has been demanded.

An object of the present invention is to cast a cellulose acylate dope solution prepared by using an organic solvent to provide a cellulose cellulose film having an excellent surface condition. The cellulose having such an excellent surface condition is provided. It is to provide a cellulose acylate dope solution suitable for producing a cellulose film. Further, the object of the present invention is to impart excellent productivity, which allows the film to be easily peeled from the (temporary) support for drying after casting,
It is an object of the present invention to provide a film having excellent film strength of the obtained cellulose acylate film. Further, an object of the present invention is to achieve the above object also in a cellulose acylate dope solution prepared by a room temperature dissolution, a cooling dissolution method or a high temperature high pressure dissolution method using a non-chlorine organic solvent.

[0008]

These objects have been achieved by the following means. (1) In a cellulose acylate dope solution in which cellulose acylate is dissolved in a solution containing an organic solvent, a cross-linking agent having two or more groups capable of reacting with at least one kind of active hydrogen is added to cellulose acylate at 0. ．
A cellulose acylate dope solution containing 1 to 10% by mass. (2) The cellulose acylate dope solution according to (1), wherein the cellulose acylate is dissolved in a solution containing an organic solvent in an amount of 10 to 30% by mass.

(3) Cellulose acylate is a cellulose acylate composed of a single or a mixture of which the degree of substitution of hydroxyl groups on cellulose satisfies all of the following formulas (I) to (III). A cellulose acylate dope solution as described in (1) or (2) above. (I) 2.6 ≦ SA + SB ≦ 3.0 (II) 2.0 ≦ SA ≦ 3.0 (III) 0 ≦ SB ≦ 0.8 where SA and SB are substituted with a hydroxyl group of cellulose. Represents the substituent of the acyl group, SA is the degree of substitution of the acetyl group, and SB is the degree of substitution of the acyl group having 3 to 22 carbon atoms.

(4) The cross-linking agent is a cross-linking agent having a bifunctional or higher functional isocyanate group, a bifunctional or higher functional epoxy group, and a bifunctional or higher functional aziridine group. The cellulose acylate dope solution as described in any one of (1) to (3) above. (5) The organic solvent is a non-chlorine organic solvent selected from ethers having 3 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, and esters having 3 to 12 carbon atoms. The cellulose acylate dope solution as described in any one of (1) to (4), which is at least one kind of solvent. (6) A method for producing a cellulose acylate film, which comprises preparing a cellulose acylate dope solution, casting the cellulose acylate dope solution on a (temporary) support, and then peeling it from the temporary support and drying. In the method for producing a cellulose acylate film, the cellulose acylate dope solution is the cellulose acylate dope solution according to any one of (1) to (5).

(7) In preparing the cellulose acylate dope solution, the cellulose acylate dope solution obtained by at least one of the following preparation methods (1) to (3) is prepared (6). The method for producing a cellulose acylate film according to item 1. (I) A step of swelling at -10 to 55 ° C,
A method for preparing a cellulose acylate dope solution, which comprises the steps of heating to ~ 55 ° C to dissolve cellulose acylate in an organic solvent. (Ii) Swelling at -10 to 55 ° C, -100 to-
Cooling to 10 ° C., and cooling the mixture to 0-5
A method for preparing a cellulose acylate dope solution, which comprises the steps of heating to 7 ° C. and dissolving the cellulose acylate in an organic solvent. (Iii) Swelling at -10 to 40 ° C, 0.2 to 3
Heating at high pressure and high temperature to 60 to 240 ° C. at 0 Mpa,
And a method for preparing a cellulose acylate dope solution, which comprises the steps of cooling the heated mixture to 0 to 57 ° C. and dissolving the cellulose acylate in an organic solvent.

(8) The cellulose acylate dope solution contains at least one liquid or solid plasticizer in an amount of 0.1 to 20% by mass based on cellulose acylate, and at least one liquid or solid ultraviolet absorber. 0.001 to 5% by mass relative to cellulose acylate,
At least one solid with an average particle size of 5 to 3000 n
At least one fluorine containing 0.001 to 5 mass% of the fine particle powder of m with respect to the cellulose acylate, and containing at least one release agent with 0.0001 to 2 mass% of the cellulose acylate. At least one type of optical anisotropy, containing 0.001 to 2% by mass of a surface-active agent with respect to cellulose acylate, and containing 0.0001 to 2% by mass of at least one deterioration inhibitor with respect to cellulose acylate 0.1 to 15% by mass of a sex control agent with respect to cellulose acylate, and /
Alternatively, the cellulose acylate dope solution according to any one of (1) to (5), which contains 0.1 to 5 mass% of at least one infrared absorber with respect to the cellulose acylate.

(9) In the cellulose acylate solution and the cellulose acylate film, which are made up of a manufacturing step in which two or more kinds of cellulose acylate solutions are co-cast simultaneously or successively in the casting step, the additive for each layer is (6) or (7), characterized in that it is a mixture of two or more kinds, that each layer has a different coating amount, and that each layer has a different film thickness after drying. A method for producing a cellulose acylate film.

(10) The casting speed is 5 to 200 m / min, the dried winding shape is roll-like, and the length thereof is 5
The length is 0 m to 10000 m, and the length in the width direction is 30 c
m to 500 cm, and / or both ends thereof are 1 μm to
The method for producing a cellulose acylate film according to (6), which is knurled at a height of 1 mm. (11) The produced cellulose acylate film is a cellulose acylate film used as an optical protective layer and has a film thickness of 10 to 500 μm or is used as a support for silver halide photographic light-sensitive materials. The method for producing a cellulose acylate film according to (6), which is a cellulose acylate film having a thickness of 30 to 250 μm.

First, the cellulose acylate preferably used in the present invention will be described in detail. The cellulose acylate of the present invention is not particularly limited as long as it exhibits the effects of the present invention. In the present invention, two or more different types of cellulose acylate may be mixed. However, among them, preferred cellulose acylates include the following materials. That is, the cellulose acylate is a cellulose acylate in which the substitution degree of the hydroxyl group of cellulose satisfies all of the following formulas (I) to (III). (I) 2.6 ≦ SA + SB ≦ 3.0 (II) 2.0 ≦ SA ≦ 3.0 (III) 0 ≦ SB ≦ 0.8 where SA and SB are substituted with a hydroxyl group of cellulose. Represents the substituent of the acyl group, SA is the degree of substitution of the acetyl group, and SB is the degree of substitution of the acyl group having 3 to 22 carbon atoms. The β-1,4-bonded glucose unit that constitutes cellulose has a free hydroxyl group at the 2-position, 3-position and 6-position. Cellulose acylate is a polymer obtained by esterifying some or all of these hydroxyl groups with an acyl group. The degree of acyl substitution is 2
For each of the 3rd, 6th, and 6th positions, the ratio of esterification of cellulose (100% esterification means a substitution degree of 1) is meant. In the present invention, the sum of the substitution degrees of SA and SB of the hydroxyl group is more preferably 2.7 to 2.96, and particularly preferably 2.80 to 2.95. Also,
The substitution degree of SB is 0 to 0.8, and particularly 0 to 0.6. Further, 28% or more of SB is a substituent of the 6-position hydroxyl group, more preferably 30% or more is a substituent of the 6-position hydroxyl group, further preferably 31%, particularly preferably 32%.
It is also preferable that the above is a substituent of the 6-position hydroxyl group. Further, a cellulose acylate film having a total substitution degree of SA and SB at the 6-position of cellulose acylate of 0.8 or more, further 0.85, and particularly 0.90 can be mentioned. With these cellulose acylate films, a solution having a favorable solubility can be prepared, and particularly in a non-chlorine organic solvent, a good solution can be prepared.

The cellulose acylate of the present invention has 3 carbon atoms.
The acyl group (SB) of 22 to 22 may be an aliphatic group or an allyl group and is not particularly limited. They are, for example, cellulose alkyl carbonyl ester, alkenyl carbonyl ester, aromatic carbonyl ester, aromatic alkyl carbonyl ester and the like, which may each have a further substituted group. These preferred SBs include propionyl, butanoyl, keptanoyl, hexanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, iso-butanoyl,
Examples thereof include t-butanoyl, cyclohexanecarbonyl, oleoyl, benzoyl, naphthylcarbonyl and cinnamoyl groups. Among these, propionyl, butanoyl, dodecanoyl, octadecanoyl,
Examples include t-butanoyl, oleoyl, benzoyl, naphthylcarbonyl and cinnamoyl.

The basic principle of the method for synthesizing cellulose acylate is described in Ueda 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. Specifically, after pre-treating a cellulose raw material such as cotton linter or wood pulp with an appropriate amount of acetic acid, the mixture is put into a pre-cooled carboxylic oxidation mixed solution to be esterified to obtain a complete cellulose acylate (2nd, 3rd and 6th). The total degree of acyl substitution at positions is about 3.00). The above-mentioned carboxylic oxidation mixed liquid generally contains acetic acid as a solvent, carboxylic acid anhydride as an esterifying agent, and sulfuric acid as a catalyst. Carboxylic anhydride is usually used in a stoichiometric excess over the total of the cellulose that reacts with it and the water present in the system. After completion of the acylation 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. Aqueous solution of carbonate, acetate or oxide). Next, the obtained complete cellulose acylate is saponified and aged by keeping it at 50 to 90 ° C. in the presence of a small amount of an acetylation reaction catalyst (generally, residual sulfuric acid),
The cellulose acylate having the desired degree of acyl substitution and degree of polymerization 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 it is added to water or diluted sulfuric acid without neutralization. Add the cellulose acylate solution (or, in the cellulose acylate solution,
Water or diluted sulfuric acid is added) to separate the cellulose acylate, and the cellulose acylate is obtained by washing and stabilizing treatment.

In the cellulose acylate film of the present invention, it is preferable that the polymer component constituting the film is substantially composed of cellulose acylate having the above definition. "Substantially" means 55% by mass or more (preferably 70% by mass or more, more preferably 80% by mass) of the polymer component.
Mass% or more). Cellulose acylate particles are preferably used as a raw material for film production. 90% by mass or more of the particles used are 0.5 to 5 mm
It is preferable to have a particle size of. Further, it is preferable that 50% by mass or more of the particles used have a particle diameter of 1 to 4 mm. It is preferable that the cellulose acylate particles have a shape as close to a spherical shape as possible.

The degree of polymerization of cellulose acylate preferably used in the present invention is a viscosity average degree of polymerization of 200 to 700,
Preferably 250 to 550, more preferably 250 to 4
00, particularly preferably a viscosity average degree of polymerization of 250 to 3
50. The average degree of polymerization is determined by the limiting viscosity method of Uda et al. (Kazuo Uda, Hideo Saito, Journal of the Fiber Society, Vol. 18, No. 1, 105
~ 120, 1962). Further, it is described in detail in JP-A-9-95538.

When the low molecular weight component is removed, the average molecular weight (polymerization degree) increases, but the viscosity becomes lower than that of ordinary cellulose acylate, which is useful. 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 low molecular components can be carried out by washing the cellulose acylate with a suitable organic solvent. When producing a cellulose citrate containing a small amount of low-molecular components, it is preferable to adjust the amount of the sulfuric acid catalyst in the acetylation reaction to 0.5 to 25 parts by mass with respect to 100 parts by weight of cellulose. When the amount of the sulfuric acid catalyst is in the above range, it is possible to synthesize a cellulose acylate which is preferable in terms of molecular weight distribution (uniform molecular weight distribution). When used in the production of the cellulose acylate of the present invention, its water content is preferably 2% by mass or less,
It is more preferably 1% by mass or less, and particularly preferably a cellulose acylate having a water content of 0.7% by mass or less. Generally, cellulose acylate contains water and is known to be 2.5 to 5 mass%. In the present invention, in order to obtain the water content of the cellulose acylate, it is necessary to dry it, and the method is not particularly limited as long as the desired water content is obtained. For these cellulose acylates of the present invention, the raw material cotton and the synthesis method are described in detail in pages 7 to 12 of the Institute of Invention and Innovation published technical report (public technique number 2001-1745, published on March 15, 2001, Institute of Invention). It is described in.

The cellulose acylate dope solution of the present invention is characterized by containing at least one kind of crosslinking agent having two or more groups capable of reacting with active hydrogen. By adding such a cross-linking agent, it is possible to interact with or bind to the free hydroxyl groups of the cellulose acylate and obtain excellent solution characteristics and film characteristics.
In the present invention, it is not particularly limited as long as it is a cross-linking agent having at least one kind of group that reacts with two or more active hydrogens, but as a group that reacts with a preferred active hydrogen, an isocyanate group, an epoxy group, an aziridine group, vinyl sulfone And a group having a succinic anhydride derivative. Among these, an isocyanate group, an epoxy group, and an aziridine group are particularly preferable. As the cross-linking agent having a group that reacts with these preferable active hydrogen, tolylene diisocyanate (trade name Coronate T-65, -80,100, Nippon Polyurethane Industry Co., Ltd.), toluentisocyanate, polymethylene polyphenyl polyisocyanate ( Trade name Millionate MR-100, -200, -30
0, -400, Nippon Polyurethane Industry Co., Ltd., triethylene diisocyanate, hexamethylene diisocyanate, polyol modified isocyanate (trade name Coronate T-1040, -1050, 1041, -109).
5, Nippon Polyurethane Industry Co., Ltd., polycarbodiimide modified isocyanate (trade name Millionate MTL,
MTL-5, Coronate 84, Coronate MX, Nippon Polyurethane Industry Co., Ltd., blended isocyanate (Coronate-1021, -1025, -1027,-)
1028, -1051, -1062, -1065, Nippon Polyurethane Industry Co., Ltd.), diphenylmethane-4,
4'-diisocyanate (Millionate MT, Millionate MT-F, Nippon Polyurethane Industry Co., Ltd.), etc. can be mentioned. Among these, tolylene diisocyanate and polymethylene polyphenyl polyisocyanate are particularly preferable.

Further, in the present invention, the epoxy group is 2
Crosslinking agents having more than one are also preferably used, and they are diepoxyalkylenes (wherein alkylene has 2 to 1 carbon atoms).
2 is preferable, and 2-6 is more preferable. Preferably, ethylene diglycidyl ether, propylene diglycidyl ether, hexylene diglycidyl ether, etc.), polyoxyalkylene diglycidyl ether (polyoxyalkylene preferably has a total carbon number of 3 to 60, more preferably 3 to 30). For example, diethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, decaethylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, etc., polyoxyglycerin polyglycidyl ether (polyoxyalkylene having a total carbon number of 3 to 60 is preferable, and more preferably 3 to 3.
It is 0. For example, triglycerin tetraglycidyl ether, hexaglycerin octaglycidyl ether, etc.), polyhydric glycidyl ether of polyhydric alcohol (total polyhydric alcohol preferably has 3 to 60 carbon atoms,
It is more preferably 3 to 30. For example, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, glycidol hexaglycidyl ether, ditrimethylolpropane tetraglycidyl ether, dipentaerythritol hexaglycidyl ether, sorbitan triglycidyl ether, etc.), benzylidene diglycidyl You can mention ether etc.
Among these, preferred crosslinking agents are ethylene diglycidyl ether, hexylene diglycidyl ether, diethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, triglycerin tetraglycidyl ether, hexaglycerin octaglycidyl ether, glycerin triglycidyl ether,
Examples thereof include trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, dipentaerythritol hexaglycidyl ether, and sorbitan triglycidyl ether. Further, in the present invention, a cross-linking agent having two or more aziridine groups is also preferably used, and these are alkylenediaridyline (wherein alkylene preferably has 2 to 12 carbon atoms,
It is more preferably 2 to 6. Preferred are ethylenebisaziridine, trimethylolpropanetriaziridine and the like.

The crosslinking agent of the present invention is characterized in that it is contained in an amount of 0.1 to 10% by mass based on the cellulose acylate, more preferably 0.2 to 5% by mass, and further preferably 0. 0.5 to 3 mass% is included. The method of adding the crosslinking agent of the present invention is not particularly limited, and the crosslinking agent may be added as it is to the cellulose acylate solution, or may be dissolved in a desired organic solvent in advance and added. The organic solvent used at this time may be the same as or different from the solvent of the cellulose acylate of the present invention, and there is no problem. Further, in the cellulose acylate solution of the present invention, the cellulose acylate, the organic solvent, the additive and the crosslinking agent of the present invention may be separately added to the dissolution tank, and a part or all of them are continuously and continuously added. But there is no problem. Further, it may be swollen in the first tank and transferred to a second dissolution tank thereafter, and may be heated or cooled during the transfer for dissolution, or may be melted in the second tank. Regarding these, JP-A-61-29031, and JP-A-2000
No. -273239.

The cellulose acylate solution of the present invention contains
Various additives (for example, plasticizers, UV inhibitors, deterioration inhibitors, optical anisotropy control agents, fine particles, release agents, infrared absorbers, etc.) can be added in each preparation step depending on the application. , They may be solid or oily. That is, the melting point and the boiling point are not particularly limited. For example, mixing of UV absorbing materials at 20 ° C. or lower and 20 ° C. or higher, mixing of plasticizers, and the like are also described, for example, in JP-A No. 2001-151901. Furthermore, the infrared absorbing dye is described in, for example, JP-A No. 2001-194522. Further, the addition may be carried out at any time in the dope preparation step, but may be carried out by adding a step of adding an additive to the final preparation step of the dope preparation step. Furthermore,
The addition amount of each material is not particularly limited as long as the function is exhibited. Further, when the cellulose acylate film is formed from multiple layers, the type and amount of the additive in each layer may be different. For example, it is described in Japanese Patent Application Laid-Open No. 2001-151902, but these are known techniques. Further details of these can be found in JIII Journal of Technical Disclosure (Kogi No. 2001-1745, March 1, 2001).
Materials described in detail on pages 16 to 22 by the Institute of Invention and Innovation, 5th day are preferably used.

Next, the organic solvent in which the cellulose acylate of the present invention is dissolved will be described. First, the non-chlorine organic solvent preferably used when preparing the cellulose acylate solution of the present invention will be described. In the present invention, the non-chlorine organic solvent is not particularly limited as long as the purpose can be achieved within the range in which the cellulose acylate can be dissolved, cast and film-formed. The non-chlorine organic solvent used in the present invention is preferably a solvent selected from esters, ketones and ethers having 3 to 12 carbon atoms. The ester, ketone and ether may have a cyclic structure. A compound having two or more functional groups of ester, ketone and ether (that is, -O-, -CO- and -COO-) can also be used as a main solvent, and other compounds such as alcoholic hydroxyl group can be used. It may have a functional group of. In the case of a main solvent having two or more kinds of functional groups, the number of carbon atoms may be within the specified range of the compound having any functional group. Examples of esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate. Examples of ketones having 3 to 12 carbon atoms include:
Mention may be made of acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone and methylcyclohexanone. Examples of ethers having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, and 1,4.
-Dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole. Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.

The non-chlorine organic solvent used for the above cellulose acylate is selected from the various viewpoints described above, but is preferably as follows. That is, the preferred solvent for the cellulose acylate of the present invention is a mixed solvent of three or more different kinds,
The solvent is at least one selected from methyl acetate, ethyl acetate, methyl formate, ethyl formate, acetone, dioxolane, dioxane or a mixture thereof, and the second solvent is a ketone having 4 to 7 carbon atoms or Selected from acetoacetic acid esters, and selected from alcohols or hydrocarbons having 1 to 10 carbon atoms as the third solvent,
More preferably, it is an alcohol having 1 to 8 carbon atoms. When the first solvent is a mixed solution of two or more solvents,
There may be no second solvent. The first solvent is more preferably methyl acetate, acetone, methyl formate, ethyl formate or a mixture thereof, and the second solvent is methyl ethyl ketone, cyclopentanone, cyclohexanone,
Methyl acetylacetate is preferred, and a mixture of these may be used.

The alcohol as the third solvent may be straight-chain, branched or cyclic and is preferably saturated aliphatic hydrocarbon. The hydroxyl group of the alcohol may be any of primary to tertiary. Examples of alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-
Includes butanol, 2-butanol, t-butanol, 1-pentanol, 2-methyl-2-butanol and cyclohexanol. Fluorine-based alcohol is also used as the alcohol. For example, 2-fluoroethanol, 2,2,2-trifluoroethanol,
2,2,3,3-tetrafluoro-1-propanol etc. are also mentioned. Further, the hydrocarbon may be linear, branched or cyclic. Both aromatic hydrocarbons and aliphatic hydrocarbons can be used. The aliphatic hydrocarbon may be saturated or unsaturated.
Examples of hydrocarbons include cyclohexane, hexane, benzene, toluene and xylene. These third
The alcohol and the hydrocarbon as the solvent may be used alone or as a mixture of two or more kinds, and are not particularly limited. Third
As a solvent of, preferred specific compounds are alcohols such as methanol, ethanol, 1-propanol,
2-propanol, 1-butanol, 2-butanol,
And cyclohexanol, cyclohexane, hexane, especially methanol, ethanol,
They are 1-propanol, 2-propanol and 1-butanol.

The above-mentioned three kinds of mixed solvents should contain the first solvent in an amount of 20 to 95% by mass, the second solvent in an amount of 2 to 60% by mass, and the third solvent in an amount of 2 to 30% by mass. Is preferred, and further the first solvent is 30 to 90 mass%,
It is preferable that the second solvent is contained in an amount of 3 to 50% by mass and the third alcohol is contained in an amount of 3 to 25% by mass. Moreover, especially the 1st solvent is 30-90 mass%, and the 2nd solvent is 3-.
It is preferable that the content of the third solvent is 30% by mass, and the third solvent is alcohol, and the content is 3 to 15% by mass. Note that when the first solvent is a mixed liquid and the second solvent is not used, the first solvent is 20 to
90% by mass, the third solvent is preferably contained in a ratio of 5 to 30% by mass, further, the first solvent is 30 to 86% by mass, and the third solvent is further contained in 7 to 25% by mass. It is preferable. The above-mentioned non-chlorine organic solvent used in the present invention is described in more detail in Japan Institute of Invention and Innovation Technical Report (publication number 2001-1745, published on Mar. 15, 2001,
Inventive Society), pages 12 to 16 for details. Examples of preferable combinations of non-chlorine-based organic solvents of the present invention include, but are not limited to, the following.

Methyl acetate / acetone / methanol / ethanol / butanol (75/10/5/5/5, parts by mass) methyl acetate / acetone / methanol / ethanol / propanol (75/10/5/5/5) , Mass part), methyl acetate / acetone / methanol / butanol / cyclohexane (75/10/5/5/5, mass part), methyl acetate / methyl ethyl ketone / methanol / butanol (80/10/5/5, mass) Part), methyl acetate / acetone / methyl ethyl ketone / ethanol / isopropanol (75/10/10/5/7,
Parts by mass), methyl acetate / cyclopentanone / methanol / isopropanol (80/10/5/8, parts by mass), methyl acetate / acetone / butanol (85/5/5,
Parts by mass), methyl acetate / cyclopentanone / acetone / methanol / butanol (60/15/15/5/6, parts by mass), methyl acetate / cyclohexanone / methanol / hexane (70/20/5/5, Parts by mass), methyl acetate / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20/5/5, parts by mass), methyl acetate / 1,3 dioxolane / methanol / ethanol (70/20/5/5) , Parts by mass), methyl acetate / dioxane / acetone / methanol / ethanol (60/20/10/5/5, parts by mass), methyl acetate / acetone / cyclopentanone / ethanol / isobutanol / cyclohexane (65 / 10 /
10/5/5/5, parts by mass),

Methyl formate / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20 /
5/5, parts by mass) Methyl formate / acetone / ethyl acetate / ethanol / butanol / hexane (65/10/10/5/5 /
5, acetone / methyl acetoacetate / methanol / ethanol (65/20/10/5, parts by mass), acetone / cyclopentanone / ethanol / butanol (65/20/10/5, parts by mass) ), Acetone / 1,3 dioxolane / ethanol / butanol (65/20/10/5, parts by mass), 1,3 dioxolane / cyclohexanone / methyl ethyl ketone / methanol / butanol (55/20/1)
0/5/5/5, parts by mass) and the like. The dope used in the present technology may contain dichloromethane in an amount of 10% by mass or less based on the total amount of the organic solvent in the present technology, in addition to the non-chlorine-based organic solvent in the present technology.

In producing the cellulose acylate solution of the present invention, a chlorine-based organic solvent may be used as a main solvent in some cases, which will be described below. In the present invention, the chlorine-based organic solvent is not particularly limited as long as the purpose can be achieved within the range in which the cellulose acylate can be dissolved, cast and film-formed. These chlorine-based organic solvents are preferably dichloromethane and chloroform.
Dichloromethane is particularly preferable. There is no particular problem in mixing an organic solvent other than the chlorine-based organic solvent. In that case, it is necessary to use at least 50% by mass of dichloromethane. The non-chlorine type organic solvent used in combination with the present invention is described below. That is, as the preferable non-chlorine-based organic solvent, a solvent selected from esters, ketones, ethers, alcohols, hydrocarbons and the like having 3 to 12 carbon atoms is preferable. The ester, ketone, ether and alcohol may have a cyclic structure. Functional groups of esters, ketones and ethers (ie -O
A compound having two or more of any one of-, -CO- and -COO-) can also be used as a solvent, and may have other functional groups such as an alcoholic hydroxyl group at the same time. In the case of a solvent having two or more kinds of functional groups,
The number of carbon atoms may be within the specified range of the compound having any functional group. Examples of esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate. Examples of ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone and methylcyclohexanone. 3 to 12 carbon atoms
Examples of ethers of 1) include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole. Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.

The alcohol used in combination with the chlorine-based organic solvent may be preferably linear, branched or cyclic, and among them, saturated aliphatic hydrocarbons are preferable. preferable. The hydroxyl group of the alcohol may be any of primary to tertiary. Examples of alcohols include methanol, ethanol, 1-propanol, 2-
Propanol, 1-butanol, 2-butanol, t-
Includes butanol, 1-pentanol, 2-methyl-2-butanol and cyclohexanol. Fluorine-based alcohol is also used as the alcohol. For example, 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1
-Propanol and the like can also be mentioned. Further hydrocarbons
It may be linear, branched or cyclic. Both aromatic hydrocarbons and aliphatic hydrocarbons can be used. The aliphatic hydrocarbon may be saturated or unsaturated. Examples of hydrocarbons include cyclohexane, hexane, benzene, toluene and xylene.

The non-chlorine type organic solvent used in combination with the chlorine type organic solvent which is the main solvent used for the above cellulose acylate is not particularly limited, but methyl acetate, ethyl acetate, methyl formate, ethyl formate, acetone, It is selected from dioxolane, dioxane, ketones or acetoacetic acid esters having 4 to 7 carbon atoms, alcohols or hydrocarbons having 1 to 10 carbon atoms. The preferred non-chlorine organic solvent used in combination is methyl acetate, acetone, methyl formate, ethyl formate, methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl acetyl acetate, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol. , 2-butanol, and cyclohexanol, cyclohexane, hexane can be mentioned. Examples of combinations of chlorine-based organic solvents that are preferred main solvents of the present invention include, but are not limited to, the following.

Dichloromethane / methanol / ethanol / butanol (75/10/5/5/5, parts by mass), dichloromethane / acetone / methanol / propanol (80/10/5/5, parts by mass), dichloromethane / Methanol / butanol / cyclohexane (75/10/5/5/5, parts by mass), dichloromethane / methyl ethyl ketone / methanol /
Butanol (80/10/5/5, parts by mass) ・ Dichloromethane / acetone / methyl ethyl ketone / ethanol / isopropanol (75/10/10/5 /
7 parts by mass), dichloromethane / cyclopentanone / methanol / isopropanol (80/10/5/8, parts by mass), dichloromethane / methyl acetate / butanol (80/1
0/10, parts by mass), dichloromethane / cyclohexanone / methanol / hexane (70/20/5/5, parts by mass), dichloromethane / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20/5/5, Parts by mass), dichloromethane / 1,3 dioxolane / methanol /
Ethanol (70/20/5/5, parts by mass), dichloromethane / dioxane / acetone / methanol / ethanol (60/20/10/5/5, parts by mass), dichloromethane / acetone / cyclopentanone / ethanol / Isobutanol / Cyclohexane (65/1
0/10/5/5/5, parts by mass), dichloromethane / methyl ethyl ketone / acetone / methanol / ethanol (70/10/10/5/5, parts by mass), dichloromethane / acetone / ethyl acetate / ethanol / butanol / Hexane (65/10/10/5/5 /
5 parts by mass), dichloromethane / methyl acetoacetate / methanol / ethanol (65/20/10/5, parts by mass), dichloromethane / cyclopentanone / ethanol / butanol (65/20/10/5, parts by mass) ), And so on.

The cellulose acylate dope solution of the present invention is preferably a solution in which cellulose acylate is dissolved in an organic solvent in an amount of 10 to 30% by mass in order to effectively exhibit the effects of the present invention, and more preferably. It is preferably 13 to 27% by mass, and particularly preferably 15 to 25% by mass of a dissolved cellulose acylate solution. The method of carrying out the cellulose acylate at these concentrations may be carried out so that the solution has a predetermined concentration at the stage of dissolution, or may be prepared as a low-concentration solution (for example, 9 to 14% by mass) in advance and then concentrated as described below. You may adjust to a predetermined high concentration solution in a process. Furthermore, after a high-concentration cellulose acylate solution in advance, it may be a predetermined low-concentration cellulose acylate solution by adding various additives, any method to achieve the above-mentioned cellulose acylate solution concentration If implemented, there is no particular problem.

Next, in the present invention, the molecular weight of the aggregate of cellulose acylate in the diluted solution prepared by adding 0.1 to 5% by mass of the cellulose acylate solution with the organic solvent having the same composition is 500,000 to.
It is preferably 10 million. More preferably,
The associated molecular weight is 1 to 6 million. This associated molecular weight can be determined by the static light scattering method. At this time, it is preferable that the radius of gyration, which is simultaneously obtained, be 40 to 200 nm. A more preferable radius of inertia square is 70 to 200 nm. Furthermore, it is preferable to dissolve so that the second virial coefficient is −2 × 10 ⁻⁴ to 4 × 10 ^−4, and more preferably the second virial coefficient is −2 × 10 ⁻⁴ to 2 × 10 ^−4. Is. Here, the definition of the associated molecular weight, the radius of inertia square and the second virial coefficient in the present invention will be described. These were measured using the static light scattering method according to the following method. The measurement was carried out in a dilute region for the convenience of the device, but these measured values reflect the behavior of the dope in the high concentration region of the present invention. First,
Dissolve cellulose acylate in the solvent used for the dope, 0.1 mass%, 0.2 mass%, 0.3 mass%, 0.4
A mass% solution was prepared. In order to prevent moisture absorption, cellulose acylate was dried at 120 ° C. for 2 hours, and the weighing was performed at 25 ° C. and 10% RH. The melting method is the method adopted at the time of melting the dope (normal temperature melting method, cooling melting method,
High temperature melting method). Then these solutions,
The solvent was filtered through a 0.2 μm Teflon filter. Then, the filtered solution was subjected to static light scattering using a light scattering measuring device (DLS-70 manufactured by Otsuka Electronics Co., Ltd.).
0), and at 25 ℃ from 30 to 140 degrees 1
It was measured at 0 degree intervals. The obtained data was analyzed by the BERRY plot method. The refractive index required for this analysis is the value of the solvent obtained by the Abbe refraction system, and the concentration gradient (dn / dc) of the refractive index is the differential refractometer (D manufactured by Otsuka Electronics Co., Ltd.).
RM-1021) and the solvent and solution used for the light scattering measurement.

Next, with respect to the preparation of the cellulose acylate solution (dope) of the present invention, the dissolution method is not particularly limited, and it may be carried out at room temperature, a cooling dissolution method or a high temperature dissolution method, or a combination thereof. It
In preparing the cellulose acylate dope solution of the present invention, it is particularly preferable to prepare the cellulose acylate dope solution obtained by at least one of the following preparation methods (1) to (3). (I) A step of swelling at -10 to 55 ° C,
A method for preparing a cellulose acylate dope solution, which comprises the steps of heating to ~ 55 ° C to dissolve cellulose acylate in an organic solvent. (Ii) Swelling at -10 to 55 ° C, -100 to-
Cooling to 10 ° C., and cooling the mixture to 0-5
A method for preparing a cellulose acylate dope solution, which comprises the steps of heating to 7 ° C. and dissolving the cellulose acylate in an organic solvent. (Iii) Swelling at -10 to 40 ° C, 0.2 to 3
Heating at high pressure and high temperature to 60 to 240 ° C. at 0 Mpa,
And a method for preparing a cellulose acylate dope solution, which comprises the steps of cooling the heated mixture to 0 to 57 ° C. and dissolving the cellulose acylate in an organic solvent. The preparation of the cellulose acylate solution (dope) is described in, for example, JP-A-5-163301 and JP-A-61-10.
6628, JP-A-58-127737, JP-A-9-95.
544, JP-A-10-95854, JP-A-10-459.
50, JP-A-2000-53784, JP-A-11-322.
946, further JP-A-11-322947, JP-A-2-
276830, JP-A-2000-273239, JP-A-1
1-71463, JP 04-259511, JP 20
00-273184, JP-A-11-323017, JP-A-11-302388 and the like describe methods for preparing a cellulose acylate solution, which can be referred to. The above-described methods for dissolving these cellulose acylates in an organic solvent can also be applied to these techniques within the scope of the present invention. For details of these, especially regarding non-chlorine-based solvent systems, JIII Journal of Technical Disclosure (Jan. 2001-1745, March 15, 2001).
Issued by Japan Institute of Invention) by the method described in detail on pages 22 to 25. Further, the dope solution of the cellulose acylate of the present invention is usually subjected to solution concentration and filtration, and similarly, the Institute of Invention and Innovation (Jpn.
1745, published by Mar. 15, 2001, Institute of Invention), page 25. When it is dissolved at a high temperature, it is almost equal to or higher than the boiling point of the organic solvent used, and in that case, it is used under pressure.

The cellulose acylate solution of the present invention preferably has a viscosity and a dynamic storage elastic modulus within a range. Add 1 mL of sample solution to the rheometer (CLS 5
00) using a Steel Cone having a diameter of 4 cm / 2 ° (both manufactured by TA Instruments). Measurement conditions are Oscillation Step / T
40 ° C to -10 ° C with the temperature ramp
Of the static non-Newtonian viscosity n * (Pa · s) at 40 ° C and the storage elastic modulus G '(P
a) asked. The sample solution was kept warm at the measurement starting temperature until the liquid temperature became constant, and then the measurement was started. In the present invention, the viscosity at 40 ° C. is 1 to 300 Pa · s, and the dynamic storage elastic modulus at −5 ° C. is 10,000 to 1 million Pa. More preferably, the viscosity at 40 ° C. is 1 to 2000 P
and the dynamic storage elastic modulus at −5 ° C. is 30,000 to
500,000 Pa, particularly preferably a viscosity at 40 ° C. of 1
It is 0 to 150 Pa · s, and the dynamic storage elastic modulus at −5 ° C. is 50,000 to 500,000 Pa.

Next, a method for producing a film using the cellulose acylate solution of the present invention will be described. As the method and equipment for producing the cellulose acylate film of the present invention, a solution casting film forming method and a solution casting film forming apparatus conventionally used for producing a cellulose triacetate film are used. The dope (cellulose acylate solution) prepared from the dissolver (pot) is temporarily stored in a storage pot, and the bubbles contained in the dope are removed to make the final preparation. The dope is sent from the dope outlet to the pressurizing die through a pressurizing constant quantity gear pump that can deliver the dope with high accuracy by the number of rotations, and the dope of the casting part running endlessly from the die (slit) of the pressurizing die. The dope film (also referred to as a web), which is dry and dried, is peeled from the metal support at a peeling point which is evenly cast on the metal support and the metal support makes one round. Both ends of the obtained web are sandwiched by clips and conveyed by a tenter while keeping the width and dried, and then conveyed by rolls of a drying device to complete the drying and wound by a winder to a predetermined length. The combination of the tenter and the roll group drying device varies depending on the purpose. In the solution casting film forming method used for the silver halide photographic light-sensitive material and the functional protective film for electronic displays, in addition to the solution casting film forming device, an undercoat layer, an antistatic layer, an antihalation layer, a protective layer, etc. A coating device is often added for surface treatment of the film.
Each of these manufacturing steps is described in detail in pages 25 to 30 of the Institute of Invention and Innovation public technical report (Kogi No. 2001-1745, issued March 15, 2001, Society of Invention).
It is classified into casting (including co-casting), metal support, drying, peeling and stretching. The casting speed is 5 to 200.
m / min, the dried winding shape is roll-like, the length thereof is 50 m to 10000 m, the widthwise length thereof is 30 cm to 500 cm, and / or both ends thereof are 1 μm to 1 mm. A method for producing a cellulose acylate film that is knurled at a height is a preferred embodiment.

In the present invention, the space temperature of the casting portion is not particularly limited, but it is preferably -50 to 50 ° C. Further, it is preferably −30 to 40 ° C., particularly preferably −20 to 30 ° C. In particular, the cellulose acylate solution cast by the space temperature at a low temperature is instantaneously cooled on the support to increase the gel strength, so that the film containing the organic solvent can be retained. As a result, the cellulose acylate can be stripped from the support in a short time without evaporating the organic solvent, and high-speed casting can be achieved. The means for cooling the space may be ordinary air, nitrogen, argon, helium or the like, and is not particularly limited. In that case, the humidity is preferably 0 to 70% RH, more preferably 0 to 50% RH. Further, in the present invention, the temperature of the support at the casting portion for casting the cellulose acylate solution is -50 to 130 ° C, preferably -3.
It is 0 to 25 ° C, and further -20 to 15 ° C. In order to maintain the temperature of the casting portion at the temperature of the present invention, cooling gas may be introduced into the casting portion, or a cooling device may be arranged in the casting portion to cool the space. At this time, it is important to take care not to attach water, and it can be carried out by using a dry gas.

In the present invention, regarding the contents and casting of each layer, the following constitutions are particularly preferable. That is, the cellulose acylate solution is a cellulose acylate solution containing at least one liquid or solid plasticizer in an amount of 0.1 to 20 mass% with respect to the cellulose acylate at 25 ° C., and / or at least A cellulose acylate solution containing 0.001 to 5% by mass of one type of liquid or solid ultraviolet absorber relative to cellulose acylate, and / or at least one type of solid having an average particle size of 5 to 5. A cellulose acylate solution containing 0.001 to 5% by mass of fine powder of 3000 nm with respect to cellulose acylate, and /
Or a cellulose acylate solution containing at least one fluorosurfactant in an amount of 0.001 to 2 mass% with respect to the cellulose acylate, and / or at least one release agent with respect to the cellulose acylate. It is a cellulose acylate solution containing 0.0001 to 2% by mass, and / or at least one deterioration inhibitor is added to the cellulose acylate in an amount of 0.0001 to 2% by mass.
A cellulose acylate solution containing 2% by mass, and / or a cellulose acylate solution containing at least one optical anisotropy control agent in an amount of 0.1 to 15% by mass based on the cellulose acylate. And / or at least one infrared absorber is contained in the cellulose acylate in an amount of 0.1 to 5% by mass based on the cellulose acylate.

In the casting step, one kind of cellulose acylate solution may be cast in a single layer, or two or more kinds of cellulose acylate solutions may be co-cast simultaneously and / or successively. When there is a casting step consisting of two or more layers, in the cellulose acylate solution and the cellulose acylate film to be produced, the composition of the chlorine-based solvent in each layer is the same or different, and each layer is The additive is one kind or a mixture of two or more kinds, the addition position of the additive to each layer is the same layer or different layers, The concentration in the solution is either the same or different in each layer, the molecular weight of the aggregates in each layer is the same or different, and the concentration of the solution in each layer is different. The temperature is the same or different, the coating amount of each layer is the same or different, the viscosity of each layer is the same Either one of the different viscosities, the film thickness after drying of each layer is the same or one of different thicknesses, and the materials present in each layer are in the same state or distribution or different state or From a cellulose acylate solution and its solution that have a distribution, that the physical properties of each layer are the same or different, or that the physical properties of each layer are uniform or have a distribution of different physical properties. It is also preferably a produced cellulose acylate film. here,
What is physical property?
45, Issued March 15, 2001, Institute of Invention), page 6-
The physical properties described in detail on page 7 are included. For example, haze, transmittance, spectral characteristics, retardation R
e, same Rth, molecular orientation axis, axis deviation, tear strength, folding endurance, tensile strength, Rt difference between inside and outside of winding, crease, dynamic friction, alkali hydrolysis, curl value, water content, residual solvent amount, heat shrinkage rate, high Wet dimension evaluation, water vapor transmission rate, flatness of base, dimensional stability, heat shrinkage onset temperature, elastic modulus, and measurement of bright spot foreign matter, and also includes impedance and surface condition used for base evaluation. It is a thing. In addition, the Society of Invention and Innovation Technical Report (Kogi No. 2001-1745, March 1, 2001)
The yellow index, transparency, thermophysical properties (Tg, heat of crystallization) and the like of cellulose acylate described in detail on page 11 by the Institute of Invention and Innovation on page 5 can also be mentioned. The production method of the present invention comprises a production step of simultaneously and / or sequentially co-casting two or more types of cellulose acylate solutions in the casting step, wherein the additive in each layer is a mixture of two or more types, and each layer is a mixture. It is preferable that the coating amount of each layer is different, and the thickness of each layer after drying is different. When the produced cellulose acylate film is a cellulose acylate film used as an optical protective layer, the thickness thereof is preferably 10 to 500 μm, and cellulose used as a support for silver halide photographic light-sensitive materials is used. When the film is an acylate film, its thickness is preferably 30 to 250 μm.

The cellulose acylate film can be subjected to a surface treatment as the case may be to improve the adhesion between the cellulose acylate film and each functional layer (for example, an undercoat layer and a back layer). For example, glow discharge treatment, ultraviolet irradiation treatment, corona treatment, flame treatment, acid or alkali treatment can be used. The glow discharge treatment here may be low-temperature plasma that occurs under a low pressure gas of 10 ^{−3 to} 20 Torr, and plasma treatment under atmospheric pressure is also preferable. The plasma-excitable gas refers to a gas that is plasma-excited under the above conditions, and examples thereof include CFCs such as argon, helium, neon, krypton, xenon, nitrogen, carbon dioxide, and tetrafluoromethane, and a mixture thereof. To be Details of these are disclosed in the Technical Bulletin for Invention
001-1745, published by Mar. 15, 2001, Institute of Invention), pages 30 to 32. 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 30 to 500.
Irradiation energy of 20-300 Kgy under Kev is used. Of these, the alkali saponification treatment is particularly preferable and is extremely effective as the surface treatment of the cellulose acylate film.

The alkali saponification treatment is carried out by applying a saponification solution. 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 treatment coating liquid is
It is preferable to select a solvent which has good wettability for applying the saponification solution to the transparent support and which keeps the surface state good without forming irregularities on the surface of the transparent support by the solvent of the saponification solution. Specifically, alcohol solvents are preferable, and isopropyl alcohol is particularly preferable. Also, an aqueous solution of a surfactant can be used as a solvent.
The alkali of the coating solution for alkali saponification is preferably an alkali soluble in the above solvent, 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 or more and 5 minutes or less at room temperature, more preferably 2 seconds or more and 1 minute or less, and particularly preferably 3 seconds or more and 30 seconds or less. After the alkali saponification reaction, the surface coated with the saponification solution is preferably washed with water or an acid and then with water. In addition, the coating-type saponification treatment and the later-described coating of the alignment film can be continuously performed, and the number of steps can be reduced.

When the cellulose acylate film of the present invention is used as a support for a silver halide light-sensitive material, in order to achieve adhesion with a silver halide emulsion layer, it is subjected to surface activation treatment and then directly subjected to cellulose acylate. A method of applying a functional layer on the film to obtain adhesive strength, and a method of applying a functional layer on the undercoat layer (adhesive layer) after some surface treatment or without surface treatment. There is a way to do it. For details of these undercoat layers, refer to the Japan Institute of Invention and Innovation Technical Report (Kogi No. 2001-1745, March 2001).
(Published on March 15, issued by the Institute of Invention) on page 32. Also, regarding the functional layers of the cellulose acylate film of the present invention, various functional layers are disclosed in the Technical Bulletin of the Institute of Invention (Kogi No. 2001-1745, published on March 15, 2001, Institute of Invention), pages 32 to 45. Are described in detail in.

The application of the cellulose acylate produced in the present invention will be briefly described first. The cellulose acylate film of the present invention is useful as an optical film, particularly as a polarizing plate protective film. When used as a polarizing plate protective film, the method for producing the polarizing plate is not particularly limited, and it can be produced by a general method. There is a method in which the obtained cellulose acylate film is treated with an alkali, and a polyvinyl alcohol film is dipped and stretched in an iodine solution and laminated on both surfaces of the polarizer using a completely saponified polyvinyl alcohol aqueous solution. Instead of the alkali treatment, easy adhesion processing as described in JP-A-6-94915 and JP-A-6-118232 may be performed. Examples of the adhesive used to bond the protective film-treated surface to the polarizer include polyvinyl alcohol adhesives such as polyvinyl alcohol and polyvinyl butyral, vinyl latex such as butyl acrylate, and the like. The polarizing plate is composed of a polarizer and a protective film that protects both surfaces thereof, and a protective film is bonded to one surface of the polarizing plate, and a separate film is bonded to the other surface. The protect film and the separate film are used for the purpose of protecting the polarizing plate at the time of shipping the polarizing plate and at the time of product inspection. In this case, the protect film is attached for the purpose of protecting the surface of the polarizing plate,
It is used on the side opposite to the side where the polarizing plate is attached to the liquid crystal plate.
Further, the separate film is used for the purpose of covering the adhesive layer that is stuck to the liquid crystal plate, and is used on the surface side where the polarizing plate is stuck to the liquid crystal plate. In a liquid crystal display device, a substrate containing a liquid crystal is usually arranged between two polarizing plates, but a polarizing plate protective film to which the optical film of the present invention is applied can obtain excellent displayability at any position. . In particular, since a transparent hard coat layer, an antiglare layer, an antireflection layer, etc. are provided on the polarizing plate protective film on the outermost surface on the display side of the liquid crystal display device, it is particularly preferable to use the polarizing plate protective film in this portion.

The cellulose acylate film of the present invention can be used for various other purposes, and is particularly effective when used as an optical compensation sheet for liquid crystal display devices.
The cellulose acylate film of the invention can be used in liquid crystal cells of various display modes. TN (Twi
Steaded Nematic), IPS (In-Plan)
e Switching, FLC (Ferroele)
ctric Liquid Crystal), AFL
C (Anti-ferroelectric Liquid)
id Crystal), OCB (Optically)
Compensation Bend), STN (S
upper Twisted Nematic), VA
(Vertical Aligned) and HA
N (Hybrid Aligned Nematic)
Various display modes such as are proposed. In addition, a display mode in which the above display mode is orientation-divided is also proposed. The cellulose acylate film is effective in liquid crystal display devices of any display mode. It is also effective in any of the transmissive, reflective, and semi-transmissive liquid crystal display devices. The cellulose acylate film of the invention may be used as a support of an optical compensation sheet of a TN type liquid crystal display device having a TN mode liquid crystal cell. The cellulose acylate film of the invention may be used as a support of an optical compensation sheet of an STN type liquid crystal display device having an STN mode liquid crystal cell. Generally, in the STN type liquid crystal display device, the rod-shaped liquid crystalline molecules in the liquid crystal cell are 90 to 36
It is twisted in the range of 0 degree and the product (Δnd) of the refractive index anisotropy (Δn) of the rod-like liquid crystalline molecule and the cell gap (d).
Is in the range of 300 to 1500 nm. Regarding the optical compensation sheet used in the STN type liquid crystal display device, see JP-A-200
It is described in Japanese Patent Publication No. 0-105316. The cellulose acylate film of the invention is particularly advantageously used as a support for an optical compensation sheet of a VA type liquid crystal display device having a VA mode liquid crystal cell. The cellulose acylate film of the invention is an OCB having an OCB mode liquid crystal cell.
Type liquid crystal display device or HAN type liquid crystal display device having a HAN mode liquid crystal cell, it is advantageously used as a support for an optical compensation sheet.

The cellulose acylate film of the present invention is TN type, STN type, HAN type, GH (Guest-type).
It is also advantageously used as an optical compensation sheet for a (Host) type reflective liquid crystal display device. These display modes have long been well known. Regarding the TN reflective liquid crystal display device, JP-A-10-123478 and WO984832
No. 0 and Japanese Patent No. 3022477 have descriptions.
The optical compensation sheet used for the reflective liquid crystal display device is described in WO00-65384. The cellulose acylate film of the present invention has an ASM (Axial)
y Symmetric Aligned Micro
It is also advantageously used as a support for an optical compensation sheet of an ASM type liquid crystal display device having a cell) mode liquid crystal cell. The ASM mode liquid crystal cell is characterized in that the cell thickness is maintained by a resin spacer whose position can be adjusted. Other properties are similar to those of the TN mode liquid crystal cell. Regarding the ASM mode liquid crystal cell and the ASM type liquid crystal display device, a paper by Kume et al.
et al. , SID 98 Digest 108
9 (1998)). The applications of these detailed cellulose acylate films described above are disclosed in JIII Journal of Technical Disclosure (Jpn. Pat. No. 2001-1745, 200).
Invention Society, published March 15, 1), pages 45-59.

[0049]

[Examples] Specific embodiments of the cellulose acylate of the present invention are described below, but the invention is not limited thereto. In each example, the chemical and physical properties of the cellulose acylate solution and the film were measured and calculated as follows.

(1) Unpeeled film residue The surface of the support when the obtained film was peeled from the support was visually observed, and the unpeeled film residue of the cellulose acylate film was evaluated as follows. A: No peeling residue is observed on the support. B: A slight peeling residue was observed on the support. C: A large amount of peeling residue was observed on the support. D: A large amount of peeling residue was observed on the support.

(2) Horizontal unevenness of film (abbreviated as unevenness) The obtained film was visually observed, and defects of the horizontal unevenness were evaluated as follows. A: No horizontal unevenness is observed on the film. B: Horizontal unevenness was slightly observed on the film. C: Lateral unevenness was considerably observed on the film. D: A large amount of horizontal unevenness was observed on the film.

(3) Hard spots on film (abbreviated as hard spots) The obtained films were visually observed and the hard spots on the surface were evaluated as follows. A: No spots were found on the film surface. B: A few spots were observed on the film surface. C: Significant spots were recognized on the film surface. D: Unevenness was observed on the film surface, and many spots were recognized.

(4) Haze of film The haze was measured using a 1001DP type (manufactured by Nippon Denshoku Industries Co., Ltd.).

Example. 1 (1-1) Preparation of Cellulose Acylate Solution In a 400 L stainless steel dissolution tank having stirring blades and circulating cooling water around the outer circumference, while well stirring and dispersing in the following solvent mixed solution, Cellulose acylate powder (flakes) was gradually added, and the whole was charged to 200 kg. In addition, as the solvent, methyl acetate, butanol, acetone, methanol, and ethanol were used, all having a water content of 0.2 mass% or less. First, as powder of cellulose triacetate, powder was put in a dispersion tank, the pressure in the tank was reduced to 1300 Pa, and the stirring shear rate was initially 15 m / sec (shear stress 5 × 10 ^4).
With a dissolver type eccentric stirring shaft that stirs at a peripheral speed of kgf / m / sec ² ) and an anchor blade on the central axis, a peripheral speed of 1 m / sec (shear stress 1 × 10 ⁴ kgf / m /
It was dispersed for 30 minutes under the condition of stirring for ² sec. The starting temperature of dispersion was 25 ° C, and the final temperature reached was 35 ° C by running cooling water. After the dispersion was completed, the high-speed stirring was stopped, the peripheral speed of the anchor blade was set to 0.5 m / sec, and the stirring was continued for 100 minutes to swell the cellulose triacetate flakes. Until the end of swelling, the inside of the tank was pressurized with nitrogen gas to 0.12 MPa. At this time, the oxygen concentration in the tank was less than 2 vol%, and there was no problem in explosion protection. It was also confirmed that the water content in the dope was 0.2% by mass or less. The composition of the cellulose acylate solution is as follows.

Cellulose triacetate (degree of substitution 2.8
2, viscosity average degree of polymerization 320, water content 0.2 mass%, viscosity of 6 mass% in dichloromethane solution 305 mPa · s,
20 parts by mass of powder having an average particle diameter of 1.5 mm and a standard deviation of 0.5 mm), a cross-linking agent of the present invention (described in Table 1), methyl acetate (58 parts by mass), acetone (5 parts by mass). , Methanol (6 parts by mass), butanol (5 parts by mass), plasticizer A (ditrimethylolpropane tetraacetate) (1 part by mass), plasticizer B (triphenyl phosphate) (1 part by mass), plasticizer C ( Biphenyl diphenyl phosphate) (0.2 parts by mass), plasticizer D (ethyl phthalyl glycol ethyl ester) (0.2 parts by mass), UV agent a (2,4-bis- (n-octylthio))
-6- (4-Hydroxy-3,5-di-tert-butylanilino) -1,3,5-triazine) (0.2 parts by mass), UV agent b (2 (2'-hydroxy-3 ', 5 '-
Di-tert-butylphenyl) -5-chlorobenzotriazole) (0.2 parts by mass), UV agent c (2 (2'-
Hydroxy-3 ′, 5′-di-tert-amylphenyl) -5-chlorobenzotriazole (0.2 parts by mass), fine particles (silicon dioxide (particle size 20 nm), Mohs hardness about 7) (0.05 parts by mass) ) And citric acid monoethyl ester (0.04 parts by mass) were used. Further, the cellulose triacetate used here has a residual acetic acid content of 0.1 mass% or less, Ca of 0.05 mass% and Mg.
Was 0.007% by mass, and Fe was 5 ppm. The 6-position acetyl group was 0.95, which was 32.2% of all acetyl groups. In addition, the acetone extract is 11
The mass% and the ratio of the weight average molecular weight to the number average molecular weight were 0.5, and the distribution was uniform. Haze is 0.0
8%, transparency was 93.5%, Tg was 160 ° C, and crystallization exotherm was 6.2 J / g.

(1-2) Cellulose triacetate film solution The obtained non-uniform gel-like solution was fed by a screw pump whose axial center was heated to 30 ° C. and cooled from the outer peripheral portion of the screw to -75. The cooling part was passed through for 3 minutes at 0 ° C. Cooling was performed using a refrigerant of -80 ° C cooled in a refrigerator. Then, the solution obtained by cooling was heated to 35 ° C. while being fed by a screw pump and transferred to a stainless steel container. After stirring at 50 ° C. for 2 hours to form a uniform solution, the solution was filtered with a filter paper having an absolute filtration accuracy of 0.01 mm (# 63 manufactured by Toyo Roshi Kaisha, Ltd.), and further a filter paper having an absolute filtration accuracy of 2.5 μm (manufactured by Pall Ltd., It was filtered through FH025). The obtained cellulose acylate solution had a viscosity (3
5 ° C.) in Pa · s and dynamic storage elastic modulus (−5 ° C.) in Pa are shown in Table 1. In addition, the degree of association polymerization is 2,500,000 to 300, irrespective of the type of the crosslinking agent and the presence or absence of the addition.
It was confirmed that the solution characteristics were within the range of the present invention.

(1-3) Preparation of Cellulose Triacetate Film The above-mentioned filtered cellulose triacetate solution at 50 ° C. was cast on a mirror-like stainless steel support which is a drum having a diameter of 3 m through a casting Giser (temperature of the support). Is -5
℃ was set). The Giesser used is JP-A-11-3.
A form similar to that described in 14233 was used. The casting speed is 75 m / min and the coating width is 200 cm.
And The temperature of the entire space of the casting part was set to 15 ° C. Then, the cellulose acylate film that had been cast and rotated 50 cm before the casting portion was peeled from the drum, and both ends were clipped with pin tenters. Thereafter, the cellulose acylate film held by the pin tenter was conveyed to the drying zone. For the first drying, 45 ° C. drying air was blown. 110 ° C, 5 minutes, 145 more
It was dried at 0 ° C. for 10 minutes (the film temperature was about 140 ° C.) to obtain a cellulose triacetate film (film thickness 80 μm). The obtained sample was cut into 3 cm at both ends and further cut from the end by 2 cm.
Knurling with a height of 100 μm was performed on a portion of 10 mm and wound into a roll.

(1-4) Results Table 1 shows the evaluation results of the obtained samples. The comparative sample 1-1 to which the cross-linking agent of the present invention was not added and the comparative sample 1-2 having a small addition amount were significantly inferior in peeling residue, unevenness, and haze. On the other hand, Samples 1-3 to 1-9 of the present invention were excellent in surface condition with no peeling residue, no unevenness, no spots, and little haze.

[0059]

[Table 1]

Example. 2 A sample 2-7 was obtained in the same manner as in Example 1 except that the (1-2) cellulose triacetate film solution was changed to the following for sample 1-5 of the present invention.

(1-2) Cellulose triacetate film solution The obtained non-uniform gel-like solution was sent by a screw pump and passed through a heating part heated at 140 ° C. and 1 Mpa for 3 minutes. , 110 ° C., 1 Mpa, and filtered with a filter paper having an absolute filtration accuracy of 0.01 mm (Toyo Roshi Kaisha, Ltd., # 63), and a filter paper having an absolute filtration accuracy of 0.0025 mm (PH, FH025). ). The obtained solution has a viscosity (35 ° C) of 85P.
It was a · s, the dynamic storage elastic modulus was 29.5 million Pa, and the molecular weight of its associated body was 2.8 million, which was within the range of the present invention.

(2-1) As a result, the sample 2-5 of the present invention was excellent in filterability, was A in peeling residue, unevenness and spots and had a haze of 0.3%, which was excellent. From this, it was confirmed that in the present invention, a cellulose acetate solution and a cellulose acetate film which are excellent in high temperature and high pressure dissolution can be produced.

Example. 3 Example. Sample 1-5 of Example 1 except that plasticizers A and B were both removed as 0 parts by weight. 1 Sample 3-5 of the present invention was prepared in exactly the same manner. The viscosity (35 ° C.) of the obtained solution was 76 Pa · s and the dynamic storage elastic modulus was 1.
It was 79,000 Pa, and its aggregate molecular weight was 3.2 million, which was within the range of the present invention. The obtained sample 3-5 had no peeling residue, unevenness and spots were both A, and haze was 0.3, which was excellent. On the other hand, when the folding endurance test was carried out, sample 1-5 showed 132 times, whereas sample 3-5, which is within the scope of the present invention and does not contain a plasticizer, had a cut endurance test of 10 times.
It was 6 times, and there was no problem in practical use, but it was slightly inferior. Therefore, in the present invention, it is clear that the cellulose acylate film containing a plasticizer is a more preferable embodiment. Here, the folding endurance was evaluated by using a sample of 120 mm ×
120mm, 23 ℃, 65% RH, humidity control for 2 hours,
According to ISO8776-1988, the number of times of reciprocation until cutting by bending was measured and evaluated.

Example. 4 Example. Example 1 except that the UV agents a, b, and c were all removed as 0 parts by weight in Sample 1-5 of Example 1. Sample 4-5 of the present invention was prepared in exactly the same manner as 1. The obtained solution had a viscosity (35 ° C.) of 85 Pa · s, a dynamic storage elastic modulus of 174,000 Pa, and an aggregate molecular weight of 3,050,000, which was within the range of the present invention. The obtained sample 4-5 had no peeling residue, unevenness and spots were evaluated as A, and haze was 0.3, which was excellent. On the other hand, when the photofading test was carried out for 1 month for a xenon lamp of 20,000 lux, the haze of Sample 1-5 was 0.6%, whereas the haze of Sample 4-5 was within the scope of the present invention. Slightly increased to 1.0%. Therefore, in the present invention, it is clear that the cellulose acylate film containing a UV agent is a more preferable embodiment.

Example. 5 Example. Example 1 except that fine particles of silica in Sample 1-5 of Example 1 were removed as 0 parts by weight. Sample 5-5 of the present invention was produced in exactly the same manner as 1. The obtained solution had a viscosity (35 ° C.) of 83 Pa · s and a dynamic storage elastic modulus of 1
It was 68,000 Pa and the aggregate molecular weight was 3,080,000, which was within the range of the present invention. The obtained sample 5-5 had no peeling residue, unevenness and spots were evaluated as A, and haze was 0.3, which was excellent. On the other hand, when two sheets of the film were stacked and examined for slipperiness, Sample 1-5 was able to smoothly move the two sheets, whereas Sample 5-5 is within the scope of the present invention, but the sample 5-5 The movement was a little bad. Therefore, in the present invention, it is apparent that the cellulose acylate film containing fine particles is a more preferable embodiment.

Example. 6 Example. 1 of the present invention sample 1-5. 1
Example 1-2 except that the production of the (1-2) cellulose triacetate film in Example 1 was changed to the following. A cellulose triacetate film of Sample 6-5 of the invention was produced in exactly the same manner as in 1. That is, a part of the cellulose triacetate solution obtained in (1-1) was sampled, and a cellulose triacetate solution (solution A) was prepared by adding 10% by mass of methyl acetate to dilute the cellulose triacetate solution. The resulting solution A is
The viscosity (35 ° C.) was 63 Pa · s, and the dynamic storage elastic modulus was 135,000 Pa, which was within the range of the present invention. The obtained solution was co-cast by stacking the cellulose triacetate solution of Sample 1-5 on the inside and the cellulose triacetate solution (solution A) on both sides thereof in accordance with the co-casting method described in JP-A-06-134993. A rolled cellulose triacetate film was obtained. The film thickness is 3 μm on both sides.
The inner thickness was set to 34 μm so that the total thickness was 40 μm. The surface condition of the obtained sample 6-5 was more excellent than that of the sample 1-5, with a smoother surface and no unevenness. Therefore, it is apparent that co-casting is an even more excellent mode in the present invention.

Example. 7 [Example 1] of JP-A No. 11-316378, the first transparent support is the same as in Example 1 of the present invention. Example 1 of JP-A No. 11-316378 was carried out in exactly the same manner except that the thickness of the cellulose triacetate film (second film) obtained in Sample 1-7 of No. 1 was changed to 100 μm. Sample 7-7 was prepared. The obtained elliptically polarizing plate had excellent optical characteristics. Therefore, it is clear that by using a specific washing solution in the production process of the present invention, a cellulose acylate film produced thereafter is a preferable mode in which there is no problem even if it is applied to an optical polarizing plate.

Example. 8 Cellulose triacetate manufactured by Fuji Photo Film Co., Ltd. in Example 1 of JP-A-7-333433 was used in Example of the present invention. An optical compensation filter film sample 8-9 was prepared in exactly the same manner as in Example 1 of JP-A-7-333433, except that the cellulose triester film of Sample 1-9 of the present invention of Example 1 was used. The obtained filter film samples 8-9 had excellent viewing angles on the left, right, top and bottom. Therefore, it can be seen that the cellulose triacetate film of the present invention is excellent for optical use.

Example. 9 In the present invention, Sample 1-7, which is used in various optical applications as a representative of the present invention, is disclosed in, for example, JP-A-10-4842.
No. 0 liquid crystal display device described in Example 1, JP-A-9-26
572 Optically anisotropic layer containing discotic liquid crystal molecules described in Example 1, alignment film coated with polyvinyl alcohol, VA type liquid crystal display device described in FIGS. When used in the OCB type liquid crystal display device shown in FIGS. 10 to 15 of 154261, good performance was obtained.

Example. 10 Example. Sample 1-5 of the present invention of Example 1 except that the film thickness is 120 μm. The film, Sample 10-5 of the present invention, was prepared in exactly the same manner as in Example 1. On one side of the obtained film, JP-A-4-737
No. 36 (Back layer composition) The first layer and the second layer of Example 1 were applied to prepare a back layer having a cationic polymer as a conductive layer. Further, sample 105 of Example 1 of JP-A No. 11-38568 was coated on the opposite surface of the obtained film base provided with a back layer to prepare a silver halide color photographic light-sensitive material. The color film obtained had excellent images and was easy to handle.

Example. 11 Example. Example 1-5 of the present invention except that butanol was changed to isopropanol and the amount was changed to 8 parts by mass. The film, Sample 11-5 of the present invention, was prepared in exactly the same manner as in Example 1. The obtained solution had a viscosity (35 ° C.) of 45 Pa · s and a dynamic storage elastic modulus of 2560,000 Pa, which was within the range of the present invention. The resulting diluted solution had an aggregate molecular weight of 4.3 million, peeling residue A, unevenness A and spot A, and a haze of 0.3, which was small and excellent in all respects.

Example. 12 Example. In the sample 1-5 of the present invention No. 1 of the present invention, the cellulose triacetate (15 parts by mass) and cellulose acetate propionate (acetyl substitution degree 2.45, propionate substitution degree 0.25 and total substitution degree 2.70) were used. , Viscosity average degree of polymerization 320, water content 0.
Viscosity of 3% by weight, 6% by weight in dichloromethane solution 27
5 mPa · s, a powder having an average particle diameter of 1.3 mm and a standard deviation of 0.4 mm, the residual acetic acid amount and propionic acid amount are both 0.05% by mass or less, Ca is 0.012% by mass, and Mg is 0. 0.07% by mass, Fe at 5 ppm, 6-position acetyl group and propionyl group at 0.70 and 0.1, respectively.
7 and 33% of all substituents, 7% by mass of acetone extracted, the ratio of the weight average molecular weight to the number average molecular weight is 0.9, the yellowness index is 1.3, the haze is 0.2, and the transparency is 93. 6%, Tg 157 ° C., crystallization heat value 4.
3 J / g) (5 parts by mass), and cellulose acetate butyrate (acetyl substitution degree 2.39, butyrate substitution degree 0.45, total substitution degree 2.84, viscosity average degree of polymerization 34).
0, water content 0.4% by mass, viscosity of dichloromethane solution 6% by mass 295 mPa · s, average particle size 1.3 mm, standard deviation 0.4 mm, residual acetic acid content and butanoic acid content are both 0.03 mass% or less, Ca is 0.0
05% by mass, Mg 0.004% by mass, Fe 5 pp
m, 6-position acetyl group and butyroyl group are each 0.7
2 and 0.20, 32% of all substituents, 14% by mass of acetone extracted, the ratio of the weight average molecular weight to the number average molecular weight is 1.3, the yellowness index is 0.9, the haze is 0.5, Transparency is 92.9%, Tg is 153 ° C., and crystallization heat value is 3.9 J / g) (5 parts by mass) The film, Sample 11-5 of the present invention, was prepared in exactly the same manner as in Example 1. The obtained solution has a viscosity (35 ° C.) of 135 Pa · s and a dynamic storage elastic modulus of 1
It was 35,000 Pa, which was within the range of the present invention. The molecular weight of the aggregate of the obtained dilute solution was 3.9 million, and the unpeeled residue A,
The unevenness A and the spot A were small, with a haze value of 0.4, and excellent in all respects. Therefore, in the present invention, an excellent cellulose acylate film can be obtained even if two or more kinds of cellulose acylate are mixed and used.

Example. 13 (13-1) Preparation of Cellulose Acylate Solution Into a 400 L stainless steel dissolution tank having a stirring blade and circulating cooling water around the outer periphery, while well stirring and dispersing the following solvent mixed solution, the following cellulose acylate Powder (flakes) was gradually added, and the whole was charged to 200 kg. It should be noted that the solvents dichloromethane, butanol, acetone, methanol, and ethanol all had a water content of 0.2 mass% or less. First,
The powder of cellulose triacetate was charged with powder in a dispersion tank, the pressure inside the tank was reduced to 1300 Pa, and the stirring shear rate was initially 15 m / sec (shear stress 5 × 10 ⁴ kg.
With a dissolver type eccentric stirring shaft that stirs at a peripheral speed of f / m / sec ² ) and an anchor blade on the central axis, a peripheral speed of 1 m / sec (shear stress 1 × 10 ⁴ kgf / m / se
It was dispersed for 30 minutes under the condition of stirring under c ² ). The starting temperature of dispersion was 25 ° C, and the final temperature reached was 35 ° C by running cooling water. After the dispersion was completed, the high-speed stirring was stopped, the peripheral speed of the anchor blade was set to 0.5 m / sec, and the stirring was continued for 100 minutes to swell the cellulose triacetate flakes. Until the end of swelling, the inside of the tank was pressurized with nitrogen gas to 0.12 MPa. At this time, the oxygen concentration in the tank was less than 2 vol%, and there was no problem in explosion protection. The water content in the dope is 0.2% by mass.
The following was confirmed. The composition of the cellulose acylate solution is as follows.

Cellulose triacetate (degree of substitution 2.8
2, viscosity average degree of polymerization 320, water content 0.2 mass%, viscosity of 6 mass% in dichloromethane solution 305 mPa · s,
20 parts by mass of powder having an average particle diameter of 1.5 mm and a standard deviation of 0.5 mm), a cross-linking agent A of the present invention (2% by mass of cellulose triacetate solid content), dichloromethane (58 parts by mass), acetone ( 5 parts by mass), methanol (6 parts by mass), butanol (5 parts by mass), plasticizer A (ditrimethylolpropane tetraacetate) (1 part by mass), plasticizer B (triphenyl phosphate) (1 part by mass), Plasticizer C (biphenyl diphenyl phosphate (0.2 parts by mass), plasticizer D (ethyl phthalyl glycol ethyl ester) (0.2 parts by mass), UV agent a
(2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-tert-butylanilino)-
1,3,5-triazine (0.2 parts by mass), UV agent b
(2 (2'-hydroxy-3 ', 5'-di-tert-
Butylphenyl) -5-chlorobenzotriazole)
(0.2 parts by mass), UV agent c (2 (2'-hydroxy-
3 ', 5'-di-tert-amylphenyl) -5-chlorobenzotriazole (0.2 parts by mass), fine particles (silicon dioxide (particle size 20 nm), Mohs hardness about 7)
(0.05 parts by mass) and citric acid monoethyl ester (0.04 parts by mass) were used. Further, the cellulose triacetate used here has a residual acetic acid content of 0.1% by mass or less, Ca of 0.05% by mass, and Mg of 0.00% by mass.
It was 7 mass%, and Fe was 5 ppm. The acetyl group at the 6-position is 0.95, which is 32.
It was 2%. The acetone extracted content was 11% by mass, and the ratio of the weight average molecular weight to the number average molecular weight was 0.5, showing a uniform distribution. The haze was 0.08%, the transparency was 93.5%, the Tg was 160 ° C., and the crystallization heat value was 6.2 J / g.

(13-2) Cellulose triacetate film solution The obtained non-uniform gel-like solution was fed by a screw pump whose axial center was heated to 30 ° C. and cooled from the outer peripheral portion of the screw to -75. The cooling part was passed through for 3 minutes at 0 ° C. Cooling was performed using a refrigerant of -80 ° C cooled in a refrigerator. Then, the solution obtained by cooling was heated to 35 ° C. while being fed by a screw pump and transferred to a stainless steel container. After stirring at 35 ° C. for 2 hours to form a uniform solution, the solution was filtered with a filter paper having an absolute filtration precision of 0.01 mm (# 63 manufactured by Toyo Roshi Kaisha, Ltd.), and further a filter paper having an absolute filtration precision of 2.5 μm (manufactured by Pall Ltd., It was filtered through FH025). The obtained cellulose acylate solution had a viscosity (3
5 Pa, 65 Pa · s, and dynamic storage modulus (-5
C.) was 285,000 Pa. The degree of association polymerization is 5
It was 100,000, and it was confirmed to have a solution property within the range of the present invention.

(13-3) Preparation of Cellulose Triacetate Film The above-mentioned filtered cellulose triacetate solution at 35 ° C. was cast onto a mirror-like stainless steel support which is a drum having a diameter of 3 m through a casting Giser (temperature of the support). Is -5
℃ was set). The Giesser used is JP-A-11-3.
A form similar to that described in 14233 was used. The casting speed is 75 m / min and the coating width is 200 cm.
And The temperature of the entire space of the casting part was set to 10 ° C. Then, the cellulose acylate film that had been cast and rotated 50 cm before the casting portion was peeled from the drum, and both ends were clipped with pin tenters. Thereafter, the cellulose acylate film held by the pin tenter was conveyed to the drying zone. For the first drying, a 35 ° C. drying air was blown. 70 ℃, 5 minutes, 145 ℃
And dried for 10 minutes (film temperature is about 140 ° C.) to obtain a cellulose triacetate film (film thickness 60 μm). The obtained sample was cut into 3 cm at both ends and further cut from the end by 2 cm.
Knurling with a height of 100 μm was performed on a portion of 10 mm and wound into a roll.

(13-4) As a result, the sample 13-1 of the present invention was excellent in surface state because all of the unpeeled residue, unevenness, and spots were A, and the haze was 0.3. Furthermore, the foreign matter size is 50 μm in diameter
The above (within 20 μm in the depth direction) is 10 m2 and 1
The number of foreign particles of 20 to 50 μm was 5 or less in 10 m 2. Further, the number of foreign matter having a size of 20 μm or less was within 5 within 2 m 2. From the above, it is clear that an excellent cellulose acylate film can be produced in the present invention.

[0078]

According to the present invention, there is provided a solution having good strippability even at high speed when the cellulose acylate film is stripped off after being cast on the support of the cellulose acylate solution in the production process. You can Furthermore, the cellulose acylate film solution of the present invention can provide a cellulose acylate film free from unevenness and spots. Further, a cellulose triester film having excellent optical anisotropy and excellent film strength can be provided. Furthermore, a cellulose triacetate film excellent as a support for a light-sensitive material can be produced.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H023 FA01                 4F071 AA09 AA42 AC12 AC19 AE02                       AG28 AG35 AG36 AH19 BA02                       BB02 BC01 BC02                 4J002 AB021 CD012 ER006 EU016                       FD142 FD146 GP00 GS00                       HA05

Claims (7)

[Claims] 1. A cellulose acylate dope solution in which cellulose acylate is dissolved in a solution containing an organic solvent, and a cross-linking agent having two or more groups capable of reacting with at least one kind of active hydrogen is added to cellulose acylate. 0.1 to 10 mass% of the cellulose acylate dope solution. 2. The cellulose acylate dope solution according to claim 1, wherein the cellulose acylate is dissolved in a solution containing an organic solvent in an amount of 10 to 30% by mass. 3. The cellulose acylate is a cellulose acylate which is a cellulose acylate having a degree of substitution of a hydroxyl group of cellulose satisfying all of the following formulas (I) to (III), and is composed of a single or a mixture. The cellulose acylate dope solution according to claim 1 or 2. (I) 2.6 ≦ SA + SB ≦ 3.0 (II) 2.0 ≦ SA ≦ 3.0 (III) 0 ≦ SB ≦ 0.8 where SA and SB are substituted with a hydroxyl group of cellulose. Represents the substituent of the acyl group, SA is the degree of substitution of the acetyl group, and SB is the degree of substitution of the acyl group having 3 to 22 carbon atoms. 4. The crosslinking agent is a crosslinking agent having a bifunctional or higher functional isocyanate group, a bifunctional or higher functional epoxy group, and a bifunctional or higher functional aziridine group. Claim 1 characterized by the above.
~ The cellulose acylate dope solution according to any one of 3 to 3. 5. The organic solvent is a non-chlorine type organic solvent, which has 3 to 12 carbon atoms, and has 3 to 1 carbon atoms.
The cellulose acylate dope solution according to any one of claims 1 to 4, which is at least one solvent selected from the ketone of 2 and the ester of 3 to 12 carbon atoms. . 6. A cellulose acylate film prepared by preparing a cellulose acylate dope solution, casting the cellulose acylate dope solution on a (temporary) support, and then peeling and drying from the temporary support. In the manufacturing method,
A method for producing a cellulose acylate film, wherein the cellulose acylate dope solution is the cellulose acylate dope solution according to any one of claims 1 to 5. 7. The method for producing a cellulose acylate dope solution, wherein the cellulose acylate dope solution is obtained from at least one of the following preparation methods (1) to (3). A method for producing the cellulose acylate film described. (I) A step of swelling at -10 to 55 ° C,
A method for preparing a cellulose acylate dope solution, which comprises the steps of heating to ~ 55 ° C to dissolve cellulose acylate in an organic solvent. (Ii) Swelling at -10 to 55 ° C, -100 to-
Cooling to 10 ° C., and cooling the mixture to 0-5
A method for preparing a cellulose acylate dope solution, which comprises the steps of heating to 7 ° C. and dissolving the cellulose acylate in an organic solvent. (Iii) Swelling at -10 to 40 ° C, 0.2 to 3
Heating at high pressure and high temperature to 60 to 240 ° C. at 0 Mpa,
And a method for preparing a cellulose acylate dope solution, which comprises the steps of cooling the heated mixture to 0 to 57 ° C. and dissolving the cellulose acylate in an organic solvent.