JP2002161144A - Cellulose acylate film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an excellent sheet shaped cellulose acylate film by the use of a nonhalogen-based organic solvent without using a halogen-based organic solvent such as methylenechloride. SOLUTION: The cellulose acylate film is formed from a cellulose acylate solution which is prepared by either cooling to -100 to -10 deg.C a mixture of a cellulose acylate having 2.6-3.0 of substitution degree of a hydroxyl group, 200-700 of average degree of viscosity in polymerization and water content of <=2 mass% and a substantially nonchlorine-based organic solvent, or heating the mixture at high temperature of 70-200 deg.C under high pressure of 0.3-30 MPa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cellulose acylate film useful for a silver halide photographic material or a liquid crystal image display.

[0002]

2. Description of the Related Art Conventionally, an organic solvent of a cellulose acylate solution used for producing a cellulose acylate used for a silver halide photographic light-sensitive material or a liquid crystal image display device is a halogen-based organic solvent such as methylene chloride. Solvent is used. Methylene chloride (boiling point 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 production process and thus is easy to dry. Conversely, methylene chloride has a low boiling point and is easy to volatilize. Improvement is desired in this respect. Therefore, a search for a solvent for cellulose acylate other than methylene chloride has been made. Acetone (boiling point: 56 ° C.), methyl acetate (boiling point: 56 ° C.), tetrahydrofuran (boiling point: 65 ° C.), 1,3-dioxolane are known as organic solvents exhibiting solubility in cellulose acylate, especially cellulose triester. (Boiling point 75 ° C.), 1,4-dioxane (boiling point 101 ° C.), and the like. However, these organic solvents have not obtained sufficient solubility for practical use by conventional dissolution methods.

[0003] As a solution to this, J. J. M. G. FIG. Cowie
Others are disclosed in Makromol. chem. 143, 105
On page (1971) cellulose triacetate (degree of acetylation from 60.1% to 61.3%) is -80% in acetone.
It is reported that after cooling from 0 ° C to -70 ° C, warming gives a 0.5 to 5 wt% dilute solution. Such a method of dissolving cellulose acylate at a low temperature is called a cooling dissolution method. In addition, Kenji Ude et al. Described spinning technology using a cooling dissolution method in "Dry spinning of cellulose triacetate from an acetone solution" in Textile Machinery Society, Vol. 34, pp. 57-61 (1981). I have.

Further, Japanese Patent Application Laid-Open Nos. 9-95538 and 9-9
JP-A-5544 and JP-A-9-95557 disclose that cellulose acylate is dissolved by a cooling dissolution method against the background of the above technology. Non-halogen organic solvents used at that time include ethers,
An organic solvent selected from ketones or esters (alcohols can be arbitrarily combined) is used. Also, Japanese Patent Application Laid-Open No. 11-60752 proposes adding a fluoroalcohol, which is a kind of alcohol, to a cellulose acylate solution.

[0005]

When a solution of cellulose acylate is prepared in a non-halogen organic solvent, it is required to further improve the solubility and to improve the surface condition of the film. An object of the present invention is to provide an excellent planar cellulose cellulose film using a non-halogen organic solvent without using a halogen organic solvent such as methylene chloride.

[0006]

The object of the present invention has been attained by the following cellulose acylate films (1) to (9). (1) between a cellulose acylate having a hydroxyl group substitution degree of 2.6 to 3.0, a viscosity average polymerization degree of 200 to 700, and a water content of 2% by mass or less, and a substantially non-chlorine organic solvent; A cellulose acylate film formed from a cellulose acylate solution prepared by cooling the mixture to −100 to −10 ° C. or heating at a high temperature and high pressure of 70 to 200 ° C. and 0.3 to 30 MPa.

(2) The cellulose acylate film according to (1), wherein the water content of the cellulose acylate is 0.01 to 1% by mass. (3) The cellulose acylate according to (1), wherein the substantially chlorine-free organic solvent is a mixed solvent containing methyl acetate, a ketone having 3 to 6 carbon atoms, and an alcohol having 1 to 4 carbon atoms. Rate film. (4) The cellulose acylate film according to (3), wherein the mixed solvent contains 20 to 90% by mass of methyl acetate, 5 to 50% by mass of ketone, and 5 to 20% by mass of alcohol.

(5) The cellulose acylate solution contains a plasticizer in an amount of 0.1 to 20% by mass based on the amount of cellulose acylate, or contains an ultraviolet absorber in an amount of 0.1% by mass based on the amount of cellulose acylate.
001 to 5% by mass, fine particle powder containing 0.001 to 5% by mass of the amount of cellulose acylate, release agent containing 0.002 to 2% by mass of the amount of cellulose acylate, or fluorine (1) The cellulose acylate film as described in (1), which contains the system surfactant in an amount of 0.001 to 2% by mass of the amount of the cellulose acylate. (6) The cellulose acylate film according to (1), wherein two or more cellulose acylate solutions are co-cast.

(7) The cellulose acylate film according to (1), which is uniaxially or biaxially stretched. (8) The cellulose acylate film according to (1), which is for an optical protective layer and has a thickness of 10 to 200 μm. (9) The cellulose acylate film according to (1), which is for a support of a silver halide photographic material and has a thickness of 30 to 250 μm.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Cellulose as a raw material for cellulose acylate includes cotton linter and wood pulp. Cellulose acylate obtained from any raw material cellulose may be used, or may be used as a mixture. A cellulose acylate in which the degree of substitution of cellulose with a hydroxyl group satisfies all of the following formulas (I) to (III) is preferable.

(I) 2.6 ≦ A + B ≦ 3.0 (II) 2.0 ≦ A ≦ 3.0 (III) 0 ≦ B ≦ 0.8 In the formula, A and B are substituted by hydroxyl groups of cellulose. A represents a substituent of an acyl group, A represents a degree of substitution of an acetyl group,
B is the degree of substitution of an acyl group having 3 to 22 carbon atoms. Cellulose has three hydroxyl groups per glucose unit, and the above numbers indicate the degree of substitution for the hydroxyl group 3.0. Cellulose triacetate generally has a degree of substitution of A of 2.6 to 3.0, and the case of B = 0 is cellulose triacetate. Cellulose acylate of the present invention,
Cellulose triacetate wherein the acyl groups are all acetyl groups, and the acetyl groups are 2.0 or more and have 3 to 3 carbon atoms.
Preferred are those having 22 or less acyl groups and 0.4 or less unsubstituted hydroxyl groups. In the case of an acyl group having 3 to 22 carbon atoms, 0.3 or less is particularly preferable from the viewpoint of physical properties. The degree of substitution can be obtained by measuring the degree of binding of acetic acid or a fatty acid having 3 to 22 carbon atoms to be substituted for a hydroxyl group of cellulose, and calculating the degree of substitution. The measurement was performed using ASTM D-
817-91.

The degree of polymerization (average viscosity) of the cellulose acylate is preferably from 200 to 700, particularly preferably from 250 to 550. Other acyl group having from 3 to 22 carbon atoms an acetyl group, a propanoyl group (C ₂ H ₅ CO-), butanoyl group _{(C 3 H 7 CO -)} (n-, iso-), valeroyl group (C ₄ H ₉ CO-) (n-, iso-, sec)
-, Tert-), octanoyl, dodecanoyl, octadecanoyl and oleoloyl. Propanoyl and butanoyl are preferred. Cellulose triacetate is preferred, especially photographic grade cellulose triacetate. In the case of commercially available photographic grade cellulose triacetate, a product satisfying qualities such as viscosity average polymerization degree and substitution degree can be easily obtained. Photographic grade cellulose triacetate is sold by Daicel Chemical Industries, Ltd., Coatles, Hoechst or Eastman Kodak.

As the acylating agent for the acyl group, acid anhydrides and acid chlorides are preferably used. A specific method for producing cellulose acylate is described in, for example, JP-A-10-45804. The concentration of the cellulose acylate solution used for producing the cellulose acylate film is preferably 5 to 30% by mass,
More preferably, it is 0 to 28% by mass.
Most preferably, it is 5% by mass. The water content of the cellulose acylate is preferably 2% by mass or less,
The content is more preferably 1% by mass or less, and most preferably 0.7% by mass or less. Generally, cellulose acylate has a water content of 2.5 to 5% by mass and needs to be dried. As a drying method, for example, drying may be carried out at a high temperature in a dryer, high-temperature air is blown, or drying at a low temperature under reduced pressure.

[0014] The preferred drying temperature is 50 to 150 ° C, more preferably 70 to 120 ° C. When performing a reduced pressure state, the pressure is 1 Pa to 0.05 MPa and further 10 P
a to 0.02 MPa, especially 50 Pa to 0.01
MPa. Further, the moisture content of the cellulose acylate may be reduced by absorbing moisture into the desiccant using the desiccant, and the cellulose acylate having the water content of the present invention may be obtained. The drying time is not particularly limited, and the drying is carried out so that the cellulose acylate of the present invention has a water content.
The water content of these cellulose acylates can be determined by collecting a certain amount of cellulose acylate and measuring with a Karl Fischer.

The organic solvent is preferably a mixed solvent comprising methyl acetate, a ketone having 3 to 6 carbon atoms and an alcohol having 1 to 4 carbon atoms. For ketones having 3 to 6 carbon atoms,
Acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, diacetone alcohol and methyl acetoacetate are included. Acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone and cyclopentanone are preferred, and acetone, methyl ethyl ketone and cyclopentanone are more preferred. Alcohols having 1 to 4 carbon atoms include methanol, ethanol, propanol, butanol, 2-fluoroethanol, 2,2,2-trifluoroethanol and 2,2,3,3-tetrafluoro-
1-propanol is included. Methanol, ethanol and butanol are preferred. Two or more ketones or two or more alcohols may be used.

In the mixed solvent, methyl acetate is 20 to 90% by mass, ketone is 5 to 60% by mass, and alcohol is 5 to 90% by mass.
-30% by mass, more preferably 30-86% by mass of methyl acetate, 7-50% by mass of ketone and 7-25% by mass of alcohol, and 30-30% by mass of methyl acetate. 80% by mass, 1 ketone
0 to 50% by mass, and 10 to 20% by mass of alcohol
As a combination example of the most preferable mixed solvent to be contained, cellulose acylate / methyl acetate / methyl ethyl ketone / acetone / methanol / ethanol (X /
(50-X) / 20/20/5/5, parts by mass), cellulose acylate / methyl acetate / acetone / methyl acetoacetate / ethanol (X / (75-X) / 20/10 //
5, parts by mass), cellulose acylate / methyl acetate / cyclopentanone / methanol / ethanol (X / (80
-X) / 10/5/5, parts by mass) and cellulose acylate / methyl acetate / acetone / methanol / ethanol (X / (80-X) / 20/5/5, parts by mass) are preferred combinations. Here, X represents a part by mass of cellulose acylate, preferably from 5 to 25, particularly preferably from 10 to 25.

In dissolving the cellulose acylate, it is preferable to previously swell the cellulose acylate in a solvent at room temperature. That is, a swelling solution of cellulose acylate can be prepared by adding the cellulose acylate powder to the solvent with good stirring or vice versa by adding the solvent to the cellulose acylate. The solvent may be a mixed solvent, or any one of the solvents may be added separately, and there is no particular limitation. By adding the alcohol first, the cellulose acylate may be easily dissolved without coagulation, and is preferably used. The preferred time for swelling is 0.1 to 24
The time is preferred, more preferably 0.2 to 6 hours, and even more preferably 0.5 to 3 hours. Since the viscosity of the mixture of the cellulose acylate and the solvent is significantly increased, a strong stirring device is preferably used. In some cases, it is preferable to use a kneader or the like or to pass through a screw extruder. For example, in the case of stirring, the peripheral speed of the stirring blade is set to 0.1.
01 to 2 m / sec, preferably 0.05 to 1.5 m
/ S, especially 0.05 to 1 m / s. Also,
The shearing force of the cellulose acylate at the time of stirring is preferably from 1 to 100,000 kgf / sec ^2, more preferably from 10,000 to 10,000 kgf / sec.
/ Sec ² is preferred.

A solution can be prepared by a cooling dissolution method.
The mixture of the swollen cellulose acylate and the solvent,
-100 to -10C, preferably -80 to -10C, more preferably -80 to -30C, most preferably -8.
Cool to 0-50C. For cooling, for example, a mechanical refrigerator (−100 ° C.), a dry ice / methanol bath (−
75 ° C) or a cooled diethylene glycol solution (-30
-20 ° C). When cooled in this way, the mixture of the cellulose acylate and the organic solvent solidifies. The cooling rate is not particularly limited, but in the case of batch-type cooling, the viscosity of the cellulose acylate solution increases with the cooling, and the cooling efficiency is inferior. is necessary. Also,
After the cellulose acylate solution is swollen, it can be achieved by transferring the cooling device at a predetermined cooling temperature for a short time. Although the cooling time is not particularly limited, the shorter the time, the better the productivity. The time is preferably 0.5 to 180 minutes, more preferably 0.5 to 30 minutes, and particularly preferably 0.5 to 10 minutes. It is. It is preferable that the cellulose acylate solution obtained by cooling is then heated to 0 to 50 ° C., thereby forming a solution in which the cellulose acylate flows in the organic solvent.

Instead of the cooling dissolution method, a dissolution method at a high pressure and a high temperature can be adopted. The organic solvent mixture of cellulose acylate is 70-
It is also preferable to dissolve by heating to 200 ° C. In this case, the heating temperature is preferably from 70 to 180C, more preferably from 70 to 160C. The heating time is not particularly limited but is preferably as short as possible, preferably from 0.5 to 60 minutes,
It is more preferably from 0.5 to 30 minutes, particularly preferably from 1 to 10 minutes. The heating method is not particularly limited. For example, high-pressure steam or an electric heat source may be used. Further, a method of dissolving in a so-called supercritical state may be adopted in which carbon dioxide gas coexists in a solvent, and it is preferable that carbon dioxide is 5 to 30% by mass in the solution. In this case, dissolution can be achieved at a lower temperature and a higher pressure. A pressure vessel or pressure line is required for high pressure, but any pressure vessel or line made of iron or stainless steel or other metal may be used. Since the heated solution cannot be handled as it is, it is necessary to cool the solution below the lowest boiling point of the solvent used. In that case,
It is common to cool to -10 to 50C and return to normal pressure. For cooling, the high-pressure high-temperature container or line containing the cellulose acylate solution may be simply left at room temperature, and more preferably, the device may be cooled using a coolant such as cooling water. The operation of heating and cooling may be repeated in order to accelerate the dissolution. Whether or not the dissolution is sufficient can be determined only by visually observing the appearance of the solution. In the high-pressure high-temperature dissolution method, a closed container is used to avoid evaporation of the solvent. In addition, in the swelling step, the dissolution time can be further reduced by increasing or decreasing the pressure. In order to perform pressurization and decompression,
A pressure-resistant container or line is essential.

As described above, the concentration of the obtained cellulose acylate solution is characterized in that a high-concentration dope can be obtained, and the cellulose acylate solution having a high concentration and excellent stability can be obtained without relying on concentration means. Is obtained. However, in some cases, it may be dissolved at a low concentration in order to further facilitate the dissolution, and then concentrated using a concentration means. The method of concentration is not particularly limited,
For example, a low-concentration solution is guided between a cylindrical body and a rotation trajectory of the outer periphery of a rotating blade rotating in a circumferential direction inside the cylinder, and a high-concentration solution is obtained while evaporating a solvent by giving a temperature difference between the solution and the solution. Method (for example, described in JP-A-4-259511), a heated low-concentration solution is blown into a container from a nozzle, and the solvent is flash-evaporated until the solution hits the inner wall of the container from the nozzle. A method of extracting the high-concentration solution from the bottom of the container (for example, US Pat. Nos. 2,541,012 and 2,858,229)
Nos. 4,414,341 and 4,504,355).

The cellulose acylate solution of the present invention comprises:
In each preparation step, various additives depending on the application can be added. The doping may be added at any time during the dope preparation step, but may be performed by adding a step of adding and preparing an additive to the last preparation step of the dope preparation step. These additives include plasticizers, UV inhibitors and deterioration inhibitors (eg, antioxidants, peroxide decomposers,
Radical inhibitor, metal deactivator, acid scavenger, amine)
It is. Phosphoric acid esters or carboxylic acid esters are preferably used as the plasticizer. Examples of phosphate esters include triphenyl phosphate (TP
P) and tricresyl phosphate (TCP). Carboxylic esters are phthalic esters and citrates, including dibutyl phthalate (DBP), dioctyl phthalate (DOP) and diethylhexyl phthalate (DEHP). Examples of citrate esters include O-acetyl triethyl citrate (OACTE) and O-acetyl tributyl citrate (OACTB), acetyl triethyl citrate, acetyl tributyl citrate. These plasticizers may be used alone or in combination of two or more. The amount of the plasticizer is 5 to 30% by mass based on the cellulose acylate.
The content is particularly preferably 8 to 16% by mass or less. These compounds may be added together with the cellulose acylate or the solvent when preparing the cellulose acylate solution, or may be added during or after the solution preparation. In addition, in the present invention, as plasticizers for reducing the optical anisotropy, (di) pentaerythritol esters described in JP-A-11-124445, glycerol esters described in JP-A-11-246704, Opening 2000-63
Diglycerol esters described in JP-A-560, citric acid esters described in JP-A-11-92574, and substituted phenylphosphates described in JP-A-11-90946 are preferably used.

As for the deterioration inhibitor and the ultraviolet inhibitor, JP-A-60-235852 and JP-A-3-199201.
No., 5-1907073, 5-194789,
5-271471, 6-107854, 6-
No. 118233, No. 6-148430, No. 7-110
Nos. 56, 7-11055, 7-11056, 8-29619, 8-239509, JP-A-200
It is described in each publication of JP-A No. 0-204173. The amount of the deterioration inhibitor to be added is preferably 0.01 to 1% by mass of the prepared cellulose acylate solution (dope).
It is more preferred that the content be from 0.01 to 0.2% by mass. A particularly preferred example of the deterioration inhibitor is butylated hydroxytoluene (BHT). In the present invention, the cellulose acylate solution more preferably contains one or more ultraviolet absorbers. The UV absorber for liquid crystal has a wavelength of 370 nm from the viewpoint of preventing deterioration of the liquid crystal.
From the standpoint of liquid crystal display properties, those having excellent ultraviolet absorbing ability and little absorption of visible light having a wavelength of 400 nm or more are preferred. For example, oxybenzophenone compounds,
Examples include benzotriazole-based compounds, salicylic acid ester-based compounds, benzophenone-based compounds, cyanoacrylate-based compounds, nickel complex salt-based compounds, and the like. Particularly preferred ultraviolet absorbers are benzotriazole-based compounds and benzophenone-based compounds. Above all, a benzotriazole-based compound is preferable because unnecessary coloring of cellulose acylate is small.

The amount of these compounds to be added is preferably 1 ppm to 1.0% by mass relative to cellulose acylate, more preferably 10 to 1000 ppm. In the present invention, a retardation increasing agent for controlling optical anisotropy is optionally added to the cellulose acylate solution. In order to adjust the retardation of the cellulose acylate film, an aromatic compound having at least two aromatic rings is preferably used as a retardation increasing agent. The optical characteristics of the present invention will be described. The in-plane retardation (Re) of the film is in the range of 0 to 300 nm depending on the application. Further, the retardation (Rth) in the thickness direction of the film is also important. Rth is 0n per 100 μm
m to 600 nm, preferably 0 to 400 nm.
More preferably, it is nm.

In forming the cellulose acylate film, it is preferable to add at least one release agent of 0.005 to 2% by mass of the solution before casting the cellulose acylate solution. Examples of the release agent, C ₁₂ H ₂₅ O-
P (= O) - (OK ) 2, C 12 H 25 OCH 2 CH 2 O-
P (= O) - (OK ) 2 and _{(iso-C 9 H 19)} 2 -C
_{6 H 3 -O- (CH 2 CH} 2 O) 3 - (CH 2) 4 SO
₃ Na are included. The amount of release agent used is 0.00
The content is preferably 2 to 2% by mass, more preferably 0.005 to 1% by mass, and most preferably 0.01 to 0.5% by mass.

When a cellulose acylate film is used as a support for a silver halide photographic light-sensitive material, a colorant compound for preventing light piping can be added. Fine particles (matting agent) can also be used to improve the slipperiness (preventing creaking) and the adhesion resistance under high humidity of the cellulose acylate film. The average height of the protrusions on the surface of the cellulose acylate film is 0.00
5 to 10 μm, preferably 0.01 to 5 μm
Is more preferable. In the case of forming projections with a spherical or irregular matting agent, the content of the matting agent is 0.1.
5 to 600 mg / m ² , preferably 1 to 40 mg / m ^2.
More preferably, it is 0 mg / m ² . As the matting agent, an inorganic substance is preferable to an organic substance. Examples of inorganic matting agents include silica, kaolin, talc, diatomaceous earth, quartz, calcium carbonate, barium sulfate, titanium oxide, alumina, manganese colloid, titanium dioxide, strontium barium sulfate or fine powder of silicon dioxide. Two or more matting agents may be used in combination. , Etc., are preferable. As the heat stabilizer, a salt of an alkaline earth metal (eg, calcium, magnesium) can be used.

Prior to casting, the solution is preferably filtered to remove foreign matters such as undissolved matter, dust, and impurities using a suitable filter material such as a wire mesh, paper, or flannel. Absolute filtration accuracy is 0.05-100 for filtration of cellulose acylate solution
It is preferable to use a filter having a μm filter, and more preferably a filter having an absolute filtration accuracy of 0.5 to 10 μm. In that case, it is 16 kg / cm ² or less (preferably 12 kg / cm ^2).
kg / cm ² or less, more preferably 10 kg / cm ² or less, particularly preferably is preferably filtered at a filtration pressure of 2 kg / cm ² or less).

As a method and equipment for producing a cellulose acylate film, 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 dissolution tank (tank) is temporarily stored in a stock tank, and the bubbles contained in the dope are defoamed or final prepared. The dope is fed from the dope discharge port to the pressurized die through a pressurized metering gear pump capable of, for example, high-precision quantitative liquid feeding according to the number of rotations, and the dope of the casting section running endlessly from the die (slit) of the pressurized die. At the peeling point where the support is evenly cast on the support and the support substantially makes a round, the freshly dried dope film (also referred to as a web) is peeled from the support. Both ends of the obtained web are sandwiched by clips, transported by a tenter while maintaining the width, and dried. Subsequently, the web is transported by a group of rolls of a drying device, dried, and wound up to a predetermined length by a winder. The combination of the tenter and the roll group drying device varies depending on the purpose. In a solution casting film forming method used for a silver halide photographic material or a functional protective film for an electronic display, in addition to the solution casting film forming apparatus,
A coating device is often added for processing the surface of the support such as an undercoat layer, an antistatic layer, an antihalation layer, and a protective layer.

The obtained cellulose acylate solution may be cast as a single layer solution on a smooth band or a drum as a support, or a plurality of cellulose acylate solutions of two or more layers may be cast. , So-called co-casting. When casting a plurality of cellulose acylate solutions, a film is produced while laminating and laminating a solution containing cellulose acylate from a plurality of casting ports provided at intervals in the traveling direction of the support, respectively. For example, Japanese Patent Application Laid-Open
158414, JP-A-1-122419, 11-
The method described in each publication of 198285 can be applied. Alternatively, the film may be formed by casting a cellulose acylate solution from two casting ports, for example, as described in JP-B-60-27562 and JP-A-61-9472.
No. 4, No. 61-947245, No. 61-104813
No. 61-158413, JP-A-6-134933
The method can be carried out by the method described in each gazette. In addition, Japanese Unexamined Patent Publication No.
A cellulose acylate film casting method of wrapping a flow of a high-viscosity cellulose acylate solution described in JP-A-6-162617 with a low-viscosity cellulose acylate solution and simultaneously extruding the high- and low-viscosity cellulose acylate solution may be used. .

Further, by using two casting ports, the film formed on the support by the first casting port is peeled off, and the second casting is performed on the side in contact with the support surface. , A film may be produced.
No. 0235. In the case of co-casting, the thickness of each layer is not particularly limited, but preferably the outer layer is preferably thinner than the inner layer.
In this case, the thickness of the outer layer is preferably from 1 to 50 μm, particularly preferably from 1 to 30 μm. Furthermore, the cellulose acylate solution of the present invention may contain other functional layers (for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer,
It is also possible to simultaneously cast an absorbing layer and a polarizing layer.

The drying of the dope on the support in the production of the cellulose acylate film is generally performed by a method in which hot air is applied from the surface side of the support (drum or belt), that is, from the surface of the web on the support. A method in which hot air is applied from the back side of the drum or belt, and a liquid whose temperature is controlled is brought into contact with the back side of the belt or drum opposite to the dope casting surface, and the drum or belt is heated by heat transfer to control the surface temperature. Although there is a heat method and the like, a backside liquid heat transfer method is preferable. The surface temperature of the support before casting may be any number of times as long as it is lower than the boiling point of the solvent used for the dope. The drying temperature in the drying step of the cellulose acylate film of the present invention is 30 to 250.
° C, particularly preferably 40 to 180 ° C.
No. 44 discloses this.

The film may be positively stretched in the width direction. The stretching in the width direction is described in JP-A-62-115035, JP-A-4-152125, JP-A-4-284221, and JP-A-4-284221.
Nos. 298310 and 11-48271. In order to increase the in-plane retardation value of the cellulose acylate film, the produced film is stretched. The stretching of the film is performed at normal temperature or under heating conditions. The heating temperature is preferably equal to or lower than the glass transition temperature of the film. The stretching of the film may be uniaxial stretching or biaxial stretching. Film stretching ratio (Ratio of increase by stretching to original length)
Is preferably 10 to 30%.

The thickness of the finished (after drying) cellulose acylate film varies depending on the purpose of use, but is usually in the range of 5 to 500 μm, and more preferably 20 to 250 μm.
Is particularly preferable, and the range of 30 to 180 μm is most preferable. In addition, the range of 30 to 110 μm is particularly preferable for optical use. The thickness of the film may be adjusted by adjusting the concentration of the solid content contained in the dope, the slit gap of the die, the extrusion pressure from the die, the speed of the support, and the like so as to obtain the desired thickness.

By performing the surface treatment of the cellulose acylate film, the adhesion between the cellulose acylate film and each of the functional layers (for example, the undercoat layer and the back layer) can be improved. In the present invention, glow discharge treatment, ultraviolet irradiation treatment, corona treatment, flame treatment, acid or alkali treatment can be used. The glow discharge treatment referred to here is so-called low-temperature plasma generated under a low-pressure gas of 10 -3 to 20 Torr. Further, an alkali saponification treatment preferably used as a surface treatment of the cellulose acylate film of the invention will be specifically described.
After immersing the surface of the cellulose acylate film in an alkaline solution, it is preferably neutralized with an acidic solution, washed with water and dried. As an alkaline solution,
Examples thereof include a potassium hydroxide solution and a sodium hydroxide solution, and the specified concentration of the hydroxide ion is preferably 0.1 N to 3.0 N, and more preferably 0.5 N to 2.0 N. The temperature of the alkaline solution is preferably in the range of room temperature to 90 ° C, more preferably 40 ° C to 70 ° C.
Next, the cellulose acylate film is generally washed with water and then passed through an acidic aqueous solution, and then washed with water to obtain a surface-treated cellulose acylate film. At this time, the acid includes hydrochloric acid, nitric acid, sulfuric acid, acetic acid, formic acid, chloroacetic acid, oxalic acid, and the like, and the concentration thereof is preferably 0.01 N to 3.0 N,
More preferably, it is 0.05N to 2.0N. When the cellulose acylate film of the invention is used as a transparent protective film of a polarizing plate, it is particularly preferable to perform an acid treatment or an alkali treatment, that is, a saponification treatment on cellulose acetate, from the viewpoint of adhesiveness to the polarizing film.

In order to achieve the adhesion between the cellulose acylate film support and the functional layer, a method of performing a surface activation treatment and then directly applying the functional layer on the cellulose acylate film to obtain an adhesive force, Undercoat layer (adhesive layer) after some surface treatment or without surface treatment
It is also preferable to provide a functional layer thereon.

In the structure of the protective film for the polarizing plate,
Anti-static layer on at least one layer of cellulose acylate film
Or hydrophilic binder for bonding to polarizer
Preferably, a layer is provided. As a conductive material,
Conductive metal oxides and conductive polymers are preferred. In addition,
A transparent conductive film formed by vapor deposition or sputtering may be used. Guidance
The conductive layer may be the outermost layer or the inner layer without any problem.
The resistance of the conductive layer is 10 ⁰-10¹²Preferably Ω
10⁰-10^TenMore preferably, it is Ω. Guidance
As the conductive material, a metal oxide is preferable. Metal oxide
Examples include ZnO, TiO_Two, SnO_Two, Al_TwoO_Three,
In_TwoO_Three, SiO_Two, MgO, BaO, MoO_Two, V
_TwoO_FiveIs included. Preferred, especially ZnO, SnO_TwoYou
And V_TwoO_FiveIs preferred. Even with metal composite oxides
Good. The conductive metal compound may be crystalline or amorphous.
Well, the shape may be spherical, needle-like, scale-like, or sol-like
It is not particularly limited. Primary particle size is 100 ° or more and 0.2
μm or less, the major axis of the higher order structure of these aggregates is 300
導電 Conducts powder having a specific structure of not less than 6 μm
The layer contains 0.01% to 20% by volume fraction.
Is preferred. , Of these conductive metal compounds
Volume resistivity is 10^-6Ω · cm-10^FiveΩ · cm
Therefore, a particularly preferable volume resistivity is 10^-6Ω · cm-10
^TwoΩ · cm.

The conductive ionic polymer compound includes an anionic polymer compound (JP-B-49-23828, JP-B-49-23828).
JP-A-23827 and JP-A-47-28937), an ionene-type polymer having a dissociating group in the main chain (JP-B-55-7334, JP-A-50-54672, JP-B-59-14735, Nos. 57-18175, 57
Nos. 18176 and 57-56059)
And a cationic pendant polymer having a cationic dissociating group in the side chain (JP-B-53-13223, JP-B-53-13223)
No. 45231, No. 55-145783, No. 55-6
No. 5950, No. 55-67746, No. 57-1134
No. 2, No. 57-15376, No. 57-19735,
Nos. 57-15376 and 58-56858, and JP-A Nos. 61-27853 and 62-9346. As the conductive material, an organic electron conductive material is also preferably used. Examples of the organic electron conductive material include a polyaniline derivative, a polythiophene derivative, a polypyrrole derivative, and a polyacetylene derivative.

A surfactant can be added to any of the functional layers. Nonionic, cationic or betaine surfactants are preferred. Further, a fluorine-based surfactant can also be used as a coating agent in an organic solvent or as an antistatic agent. Any layer above the cellulose acylate film can contain a slip agent. Examples of the slipping agents include polyorganosiloxanes (described in JP-B-53-292), higher fatty acid amides (described in U.S. Pat. No. 4,275,146), and higher fatty acid esters (see JP-B-58-33541, JP-A-55-1982). 12
Nos. 6238 and 58-90633 and British Patent No. 927446). The higher fatty acid ester is a fatty acid having 10 to 24 carbon atoms and a fatty acid having 10 carbon atoms.
Esters with ２４24 alcohols are preferred.

The cellulose acylate film formed from the cellulose acylate solution can be used for various purposes. The cellulose acylate film is particularly effective when used as an optical compensation sheet for a liquid crystal display. As the cellulose acylate film, the film itself can be used as an optical compensation sheet. When the film itself is used as the optical compensation sheet, the transmission axis of the polarizing element (described later) and the slow axis of the optical compensation sheet made of the cellulose acylate film are arranged so as to be substantially parallel or perpendicular. Is preferred. The arrangement of such a polarizing element and an optical compensation sheet is described in JP-A-10-48420.
The liquid crystal display device has a liquid crystal cell holding liquid crystal between two electrode substrates, two polarizing elements disposed on both sides thereof,
And at least one optical compensatory sheet is disposed between the liquid crystal cell and the polarizing element. The liquid crystal layer of a liquid crystal cell is usually formed by enclosing liquid crystal in a space formed by sandwiching a spacer between two substrates. The transparent electrode layer is formed on a substrate as a transparent film containing a conductive substance. The liquid crystal cell may further be provided with a gas barrier layer, a hard coat layer or an undercoat layer (used for bonding the transparent electrode layer). These layers are usually provided on a substrate. The substrate of the liquid crystal cell is generally 80 to 5
It has a thickness of 00 μm.

The optical compensation sheet is a birefringent film for removing coloring of the liquid crystal screen. The cellulose acylate film can be used as an optical compensation sheet. Further, a function may be provided as an antireflection layer, an antiglare layer, a λ / 4 layer, or a biaxially stretched cellulose acylate film. Also, to improve the viewing angle of the liquid crystal display device,
The cellulose acylate film of the invention and a film exhibiting the opposite birefringence (in the positive / negative relationship) may be used as an optical compensation sheet. The thickness range of the optical compensation sheet is the same as the preferred thickness of the film of the present invention described above. Examples of the polarizing film of the polarizing element include an iodine-based polarizing film, a dye-based polarizing film using a dichroic dye, and a polyene-based polarizing film. All polarizing films are generally manufactured using a polyvinyl alcohol-based film. The protective film of the polarizing plate
It preferably has a thickness of 25 to 350 μm,
More preferably, it has a thickness of ~ 200 [mu] m. The liquid crystal display device may be provided with a surface treatment film. The functions of the surface treatment film include a hard coat, an anti-fog treatment, an anti-glare treatment and an anti-reflection treatment. An optical compensatory sheet in which an optically anisotropic layer containing a liquid crystal (particularly discotic liquid crystal molecules) is provided on a support has also been proposed (JP-A-3-93).
No. 25, No. 6-148429, No. 8-50206,
No. 9-26572). A cellulose acylate film can also be used as a support for such an optical compensation sheet. The cellulose acylate film is a support for an optical compensation sheet of a VA liquid crystal display device having a VA mode liquid crystal cell, an OCB liquid crystal display device having an OCB mode liquid crystal cell, or a HAN liquid crystal display having a HAN mode liquid crystal cell. Support for the optical compensation sheet of the device, ASM (Axially Symmetric AlignedM
It is preferably used as a support for an optical compensation sheet of an ASM type liquid crystal display device having a liquid crystal cell of an icrocell) mode.

[0040]

EXAMPLES In each example, the characteristics were evaluated as follows.

(1) Vertical Streak Unevenness of Film (abbreviated as streak) The obtained film was visually observed, and the defect of the vertical streak unevenness was evaluated as follows. A: No vertical stripe-like unevenness is observed in the film. B: Slight vertical streak-like unevenness was observed in the film. C: The film had considerable vertical streak-like unevenness. D: A large amount of vertical streak-like unevenness was observed in the film.

(2) Film spots (abbreviated as spots) The obtained films were visually observed, and spots on the surface were evaluated as follows. A: No bumps were observed on the film surface. B: Slight bumps were observed on the film surface. C: Considerable bumps were observed on the film surface. D: Irregularities were observed on the film surface, and many spots were observed.

(3) Folding test of film A sample cut to 120 mm was subjected to ISO 8776 / 2-1.
According to the standard of 988, the number of reciprocations until cutting by bending was determined.

(4) Optical defect of film (abbreviated as white spots) The obtained cellulose acylate film is sandwiched between two polarizers placed in a crossed Nicols (orthogonal), and light is emitted from one side. Irradiate and observe from the other. 3 observed at this time
White spots of 5 μm or more per mm 2 were evaluated as follows (transmission microscope × 100). A: There were no more than 20 white spots. B: 20 to 50 white spots were observed. C: 50 to 100 blank spots were observed. D: 100 or more white spots were observed.

Example 1 (1-1) Preparation of Cellulose Triacetate Solution A cellulose triacetate solution was prepared according to the following formulation. A cellulose triacetate powder (average size: 2 mm) was gradually added to a 20-L stainless steel dissolution tank having stirring blades (washed sufficiently with methylene chloride in advance) while thoroughly stirring the following solvent mixed solution, and a total of 10 kg was added. It was charged to become. After addition, room temperature (25
C) for 3 hours at 25 ° C to swell the cellulose triacetate. In addition, methyl acetate, cyclopentanone, acetone, methanol, and ethanol, which are solvents, all have a water content of 0.2% by mass or less.

処方 Formulation of cellulose triacetate solution ─────── ───────────────────────────── Cellulose triacetate (degree of substitution 2.77%, viscosity average degree of polymerization 320, water content 0.1 20% by mass Methyl acetate 43 parts by mass Cyclopentanone 10 parts by mass Acetone 5 parts by mass Methanol 5 parts by mass Ethanol 5 parts by mass Dipentaerythritol hexaacetate (plasticizer) A) 6 parts by mass triphenyl phosphate (plasticizer B) 6 parts by mass Silica fine particles having a particle diameter of 20 nm 0.1 part by mass 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5) -Ji- tert-butylanilino) -1,3,5-triazine (UV agent a) 0.1 parts by mass 2 (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5-chlorobenzotriazole ( UV agent b) 0.1 parts by weight 2 (2'-hydroxy-3 ', 5'-di -tert- amylphenyl) -5-black Le benzotriazole (UV agent c) 0.1 part by weight C ₁₂ H _{25 OCH 2 CH 2 O-P (} = O) - (OK) 2 0.05 parts by ───────────────────────────── ───────

(1-2) Preparation of Cellulose Triacetate Film Solution (Cooling and Dissolution) The cellulose acylate solution of (1-1) was fed by a screw pump, and the cooled part was heated at -70 ° C. for 3 minutes. Let it pass. The cooling was performed using a refrigerant at −80 ° C. cooled by a refrigerator. Then, the solution obtained by cooling was transferred to a stainless steel container and stirred at 50 ° C. for 2 hours. Then, filtration was performed with a filter paper (# 63, manufactured by Toyo Roshi Kaisha, Ltd.) having an absolute filtration accuracy of 0.01 mm.

(1-3) Preparation of Cellulose Triacetate Film Solution (High Temperature and High Pressure Dissolution) The cellulose triacetate solution obtained in (1-1) was fed by a screw pump, and heated and pressurized to 180 ° C. and 1 Mpa. After passing through the heating part for 3 minutes, it was cooled to 50 ° C., and a filter paper with an absolute filtration accuracy of 0.01 mm (Toyo Roshi Kaisha, Ltd.)
(# 63).

(1-4) Preparation of Cellulose Triacetate Film The cellulose triacetate solution obtained from the mixed solution of (1-1) was cooled to 50 ° C. by the cooling dissolution method of (1-2), and a mirror-surface stainless steel support was passed through a casting Gieser. Cast on the body. The support temperature is 10 ° C and the casting speed is 30m
/ Min and the coating width was 100 cm. Drying was performed by blowing a drying air at 55 ° C. After 10 minutes, peel off from the mirror-finished stainless steel support.
After drying at 30 ° C. for 30 minutes, a cellulose triacetate film (film thickness: 80 μm) was obtained. (Sample 1-1) The cellulose acetate solution was all used, and the dissolution tank and the liquid feed system were in a state in which some skinning occurred. Sample 1
Reference No. -1 was used to prepare Reference materials 1-2 to 1-8 in the same manner except that the water content in triacetyl cellulose and the method of dissolving the sertose ester solution were changed as shown in Table 1.

(1-5) Results As is evident from Table 1, the film prepared using the cellulose triacetate having a water content of the present invention satisfied all of the streaks, spots and white spots. . On the other hand, in Comparative Samples 1-6 to 1-8 prepared using cellulose triacetate having a water content exceeding the range of the present invention, the streaks and spots were deteriorated, and the white spots were particularly poor. From the above, it is apparent that in the present invention, by reducing the water content of cellulose acylate, it is excellent in terms of uneven streaks, spots, and white spots.

[0051]

[Table 1]

Example 2 Sample 1-2 was prepared in the same manner as in Example 1 except that 43 parts by mass of methyl acetate of (1-1) cellulose triacetate solution in Example 1 was changed to 38 parts of methyl acetate and 10 parts of acetone. Sample 2-2 was obtained in exactly the same manner. The obtained sample 2-2 of the present invention was excellent in A for both uneven streaks and spots, and excellent in white spots.

Example 3 For sample 1-2, 43 parts by mass of the methyl acetate of the (1-1) cellulose triacetate solution of Example 1 were mixed with 30 parts of methyl acetate and dioxolane 13
Sample 3-
2 was obtained. The obtained sample 3-2 of the present invention is
Both the spots were A and the white spots were also excellent in A.

Example 4 A sample 1-1 was prepared in exactly the same manner as in Example 1 except that the methanol in the (1-1) cellulose triacetate solution in Example 1-1 was changed to 5 parts by mass of butanol. 4-1 was obtained. In the obtained sample 4-1 of the present invention, both the streaks and the spots were A, and the white spots were also excellent in A.

Example 5 A sample 1-3 was prepared in exactly the same manner as in Example 1 except for the following (1-1) preparation of a cellulose triacetate solution (high-temperature and high-pressure dissolution) in Example 1 except for the following. 5-3 was obtained. The obtained sample 5-3 of the present invention was excellent in A for both the streaks and the spots, and excellent in white spots. That is, the cooled and dissolved cellulose triacetate film gel solution obtained in (1-2) was kept at -75 ° C, and crushed dry ice was added thereto at 20% by mass and mixed well. The obtained cellulose acylate solution containing carbon dioxide was fed by a screw pump, passed through a heated portion heated and pressurized to 100 ° C. and 3 MPa for 3 minutes, and then cooled to 50 ° C. to obtain an absolute filtration accuracy of 0. 01 mm filter paper (manufactured by Toyo Roshi Kaisha, Ltd., #
63).

Example 6 Sample 6-3 of the present invention was prepared in exactly the same manner as in Example 1 except that both plasticizers A and B were removed as 0 parts by mass in Sample 1-3 of Example 1. Produced. In the obtained sample 6-3, the streaks slightly deteriorated in B, but there was no problem in practical use. The spots were A and the white spots were A. On the other hand, when the cut resistance test was carried out, Sample 1-3 was 105 times, whereas Sample 6-3 which is within the scope of the present invention but did not have a plasticizer had a cut resistance test of 84 times, indicating no practical problem. It was slightly inferior. Therefore, it is clear that in the present invention, it is a more preferable embodiment that the cellulose acylate film contains a plasticizer.

Example 7 A sample 7-2 of the present invention was prepared in the same manner as in Example 1 except that the UV agents a, b, and c were all removed as 0 parts by mass in the sample 1-2 of Example 1. Produced. The obtained sample 7-2 was evaluated as excellent in all of streaks, spots, and white spots, and was excellent. On the other hand, when the light-fading test was performed for 1 month with a xenon lamp of 30,000 lux, Sample 1-2 was found to have a haze (manufactured by Nippon Denshoku Industries Co., Ltd.).
The haze of sample 7-2 was slightly increased to 0.9, whereas the haze of sample 7-2 was 0.9%, whereas the haze of sample 7-2 was 100%.
-2 was 0.2% and sample 7-2 was 0.2%). Therefore, it is clear that in the present invention, it is a more preferable embodiment that the cellulose acylate film contains a UV agent.

Example 8 A sample 8-2 of the present invention was produced in exactly the same manner as in Example 1, except that the fine particles of silica were removed from the sample 1-2 of Example 1 as 0 parts by mass.
Sample 8-2 obtained was rated A for uneven streaks, spots, and white spots, and had an excellent haze of 0.1. On the other hand, when the two films were stacked and the slipperiness was examined, it was found that Sample 1-2 could be moved smoothly, whereas Sample 8-2 was within the scope of the present invention. The movement was a little bad. Therefore, it is clear that in the present invention, it is a more preferable embodiment that the cellulose acylate film contains fine particles.

[0059] For Example 9 Sample 1-2, Example 1 (1-1) further to the cellulose triacetate _{solution, C 12 H 25 OCH 2 CH} 2 O-P (= O) - (OK)
_A sample 9-2 was obtained in exactly the same manner as in Example 1 except that ₂ ) was not added. The obtained sample 9-2 of the present invention is:
Both the streaks, buttocks and margins are A and the haze is also 0.
2 was excellent. In addition, sample 9-2 of the present invention was slightly inferior in load at the time of peeling (approximately 1.2 times as much load) as sample 1-2, but inferior in practical use. . From the above, it is apparent that in the present invention, the cellulose acylate film cast by adding the release agent is excellent in releasing from the support.

Example 10 For sample 1-3, (1-1) cellulose triacetate solution of Example 1 was further added to (C ₈ F ₁₇ CH ₂ CH ₂ O (CH ₂ CH ₂ O) ₁₆ H).
Was added in the same manner as in Example 1 except that 0.05 parts by mass of was added to obtain Sample 10-3. Obtained sample 10- of the present invention
Sample No. 3 was excellent in that both uneven streaks, spots and margins were A, and haze was 0.2. The sample 10-3 of the present invention hardly adhered to the ash of tobacco. On the other hand, in sample 1-3, tobacco ash adhered. From the above, it is clear that, in the present invention, the cellulose acylate film cast by adding the fluorine-based surfactant is excellent in dusting.

Example 11 The present invention was performed in the same manner as in Example 1 except that the preparation of the cellulose triacetate film (1-2) of Example 1 was changed from the sample 1-2 of Example 1 as follows. Of the cellulose triacetate film of Sample 11-2. That is, a part of the cellulose triacetate solution obtained in (1-1) was collected, and a cellulose triacetate solution (solution A) was prepared by adding 10% by mass of methyl acetate and diluting the resultant. According to the co-casting method described in JP-A-06-134993, the cellulose triacetate solution of Sample 1-2 was placed inside, and a cellulose triacetate solution (solution A) was co-cast on both sides thereof. A rolled cellulose triacetate film was obtained. The film thickness is 3 on both sides.
The internal thickness was set to 34 μm, and the total thickness was set to 40 μm. The surface state of the obtained sample 11-2 is the same as that of sample 1-2
The surface was smoother and had no irregularities, and streaks, spots and white spots were A, which were excellent. Therefore, it is clear that co-casting is a more excellent aspect in the present invention.

Example 12 For sample 1-2, 48 parts by mass of methyl acetate of (1-1) cellulose triacetate solution of Example 1 was added to 48 parts by mass of methylene chloride.
Comparative sample 1 was prepared in exactly the same manner as in Example 1 except that cyclopentanone was changed to 10 parts by mass of methylene chloride.
2-2 was obtained. In the obtained comparative sample 12-2, although the streaks were B, the spots were inferior to C, and the white spots, D, and haze were as poor as 0.7. Therefore, it is clear that the non-halogen organic solvent of the present invention is excellent.

[Embodiment 13] JP-A-11-316378
In [Example 1] of the publication, the thickness of the first transparent support was set to 100 μm for the cellulose triacetate film (second film) obtained in Sample 1-2 of Example 1 of the present invention.
Example 1 of JP-A-11-316378 was carried out in exactly the same manner except that the value was changed to m. The obtained elliptically polarizing plate had excellent optical characteristics. Therefore, it is clear that the use of a specific washing solution in the production process of the present invention is a preferable embodiment without any problem even if the cellulose acylate film produced thereafter is applied to an optical polarizing plate.

Example 14 Sample 1 of the present invention of Example 1
-2 cellulose triester film as disclosed in
No. 333433, cellulose triacetate manufactured by Fuji Photo Film Co., Ltd. of Example 1 was used as the sample 1 of the present invention.
An optical compensating filter film sample was prepared in exactly the same manner as in Example 1 of JP-A-7-333433 except that the cellulose triacetate film of No.-2 was used. The obtained filter film had excellent viewing angles in the right, left, up and down directions. Therefore, it is understood that the cellulose triacetate film of the present invention is excellent for optical use.

[Example 15] In the present invention, a sample 1-2 was used as a representative of the present invention.
For example, the liquid crystal display device described in Example 1 of Japanese Patent Application Laid-Open No. H10-4842 and the Example 1 of Japanese Patent Application Laid-Open No. 9-26572
20. An optically anisotropic layer containing discotic liquid crystal molecules, an alignment film coated with polyvinyl alcohol,
VA-type liquid crystal display device described in FIGS. 2 to 9 of 00-154261, and FIG. 1 of JP-A-2000-154261.
When used for the OCB type liquid crystal display devices described in Nos. 0 to 15, good performance was obtained.

Example 16 Sample 16-2 of the present invention, which is a film of Example 1-2, was prepared in exactly the same manner as in Example 1 except that the film thickness was changed to 120 μm. did. The first layer and the second layer of (back layer composition) of Example 1 of JP-A-4-73736 were applied to one of the obtained films to prepare a back layer having a cationic polymer as a conductive layer. . Further, the sample 105 of Example 1 of JP-A-11-38568 was applied to the opposite side of the film base to which the obtained back layer was provided, to produce a silver halide color photographic light-sensitive material. The obtained color film was excellent in image quality and had no problem in handling.

[0067]

According to the present invention, a solution in which cellulose acylate is stably dissolved in an organic solvent other than a halogen-based organic solvent can be obtained. Furthermore, it is possible to obtain a cellulose acylate film having an excellent surface condition.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 1/00 C08L 1/00 4J002 G02B 5/30 G02B 5/30 G03C 1/795 G03C 1/795 // B29K 1:00 B29K 1:00 B29L 9:00 B29L 9:00 F term (reference) 2H023 FA01 FA13 2H049 BA04 BA06 BB13 BB33 BB49 BC09 BC22 4F070 AA02 AC23 AC36 AC37 AC39 AC43 AC45 AC47 AC50 AC55 AC66 AE01 AE02 AE03 AE03 AE02 CA11 CB05 CB11 4F071 AA09 AB18 AB21 AB24 AB26 AB30 AC05 AC07 AC10 AC11 AC12 AC13 AC15 AC19 AE04 AE05 AE11 AE19 AH19 BB02 BB07 BB08 BC01 4F205 AA01 AB07 AB10 AB11 AB14 AC05 AG03 GA07 GB02 GB26 GC02 GC07 DE002 AB02 DJ049 ED057 EE037 EH046 EH096 EH146 EJ007 EJ027 EU177 EV258 EW046 EW048 EZ007 FD026 FD168 FD179 FD310 GP03 HA05

Claims (9)

[Claims] 1. A hydroxyl group substitution degree of 2.6 to 3.0, a viscosity average polymerization degree of 200 to 700, and a water content of 2% by mass.
A mixture of the following cellulose acylate and a substantially non-chlorinated organic solvent is cooled to -100 to -10 ° C or heated at a high temperature and pressure of 70 to 200 ° C and 0.3 to 30 MPa. A cellulose acylate film formed from the prepared cellulose acylate solution. 2. The cellulose acylate having a water content of 0.0
The cellulose acylate film according to claim 1, wherein the content is 1 to 1% by mass. 3. The substantially non-chlorine organic solvent is a mixed solvent containing methyl acetate, a ketone having 3 to 6 carbon atoms and an alcohol having 1 to 4 carbon atoms.
3. The cellulose acylate film according to 1.). 4. A mixed solvent comprising 20 to 90% by mass of methyl acetate, 5 to 50% by mass of ketone and 5 to 20% by mass of alcohol.
4. The cellulose acylate film according to claim 3, wherein the content of the cellulose acylate film is about 3 wt%. 5. The cellulose acylate solution contains a plasticizer in an amount of 0.1 to 20% by mass based on the amount of the cellulose acylate or an ultraviolet absorber containing 0.04% by mass of the cellulose acylate.
Contains from 0.01 to 5% by mass, contains fine particle powder in an amount of 0.001 to 5% by mass of the amount of cellulose acylate, contains a release agent in an amount of 0.002 to 2% by mass of the amount of cellulose acylate,
Alternatively, the cellulose acylate film according to claim 1, comprising a fluorine-based surfactant in an amount of 0.001 to 2% by mass of the amount of the cellulose acylate. 6. The cellulose acylate film according to claim 1, wherein two or more cellulose acylate solutions are formed by co-casting. 7. The cellulose acylate film according to claim 1, which is stretched uniaxially or biaxially. 8. An optical protective layer, having a thickness of 10 to 20.
The cellulose acylate film according to claim 1, which has a thickness of 0 µm. 9. The cellulose acylate film according to claim 1, which is used for a support of a silver halide photographic light-sensitive material and has a thickness of 30 to 250 μm.