JPH11246704A - Plasticizer for cellulose lower fatty acid ester, cellulose ester film, and preparation thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the stability in a cellulose ester soln. and to reduce the optical anisotropy in a cellulose film, by comprising a glyceride having acyl groups with the carbon numbers in a specified range. SOLUTION: A glyceride used as a plasticizer for a cellulose lower fatty acid ester is of the formula (R<1> to R<3> are each a 2-18C acyl group or H, further at least two of R<1> to R<3> are 2-18C acyl groups and at least one of them is a 5-18C acyl group). A cellulose ester and the glyceride are mixed with an organic solvent contg. 50 wt.% or more of acetone or methyl acetate and are allowed to swell. A swollen mixture is chilled to -100 to 10 deg.C, then the chilled mixture is treated by warming to 0 to 200 deg.C to prepare a soln. having a cellulose ester concn. of 0-40 wt.% and a glyceride concn. of 0.2-5 wt.%. Casting the prepared cellulose ester soln. onto a supporting body then evaporating the organic solvent forms a cellulose film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasticizer for a lower fatty acid ester of cellulose, a cellulose ester film and a method for producing the same.

[0002]

2. Description of the Related Art Cellulose lower fatty acid ester films are used for various photographic materials and optical materials because of their toughness and flame retardancy. Cellulose ester film is
It is a support for a typical photographic light-sensitive material. Further, cellulose ester films have been used in liquid crystal display devices, which have recently been expanding in market due to their optical isotropy. Typical applications in liquid crystal display devices include protective films for polarizing plates, supports for optical compensation sheets, and color filters. Many improvements have been proposed for cellulose ester films and methods for producing the same. Recently, a method has been proposed in which a mixture of cellulose acetate and an organic solvent is cooled and further heated to dissolve the cellulose acetate in an organic solvent to prepare a cellulose acetate solution (Japanese Patent Application Laid-Open No. 9-95538). 9-95544, 9
-95557). According to the method having the cooling step and the heating step (hereinafter, referred to as a cooling dissolution method), even in the case of a combination of cellulose acetate and an organic solvent, which could not be dissolved by the conventional method,
A solution can be prepared. The cooling dissolution method is particularly effective when producing a film from triacetyl cellulose having low solubility (average degree of acetylation is 58% or more).

[0003] Plasticizers are important (substantially essential) additives for cellulose ester films. Representative examples of the plasticizer used for the cellulose ester include a phosphate plasticizer such as triphenyl phosphate (TPP) and an aromatic carboxylic acid ester plasticizer such as dimethyl phthalate (DMP). Various plasticizers used for cellulose plastics are disclosed on page 121 of Plastics Material Course 17 "Cellulosic Resins", Maruzawa et al., Published by Nikkan Kogyo Shimbun (Showa 45). However, plasticizers other than phosphoric acid esters and aromatic carboxylic acid esters have various problems and are hardly used in practice. For example, lower fatty acid ester (glyceride) plasticizers of glycerin, such as glycerin triacetate, glycerin tripropionate and glycerin tributyrate, have a problem of high water absorption. Cellulose plastics, especially cellulose acetate, have a problem of poor water resistance. Therefore, when a plasticizer having a high water absorption is used, a problem of water resistance (for example, a problem that the surface is whitened by an alkali aqueous solution treatment) is caused. Will be encouraged. When the cellulose ester film is used for optical applications, it may be treated with alkaline water in order to enhance the adhesion with other materials. In this case as well, it is necessary to keep the film surface unchanged, and additives that degrade the water resistance of the film cannot be used.

[0004]

In the production of a cellulose ester film, the stability of the cellulose ester solution is particularly important. When transferring the solution, it is necessary to avoid the generation of undissolved matter in the piping and the solidification during the downtime for maintenance of the manufacturing equipment. When a cellulose ester film is used as an optical material, optical anisotropy (eg, retardation value in the thickness direction)
Needs to be smaller. According to the study of the present inventors, the cellulose ester solution obtained by the cooling dissolution method includes:
There is a problem that stability is low. Further, the cellulose ester film produced by the cooling dissolution method has a problem that the retardation value in the thickness direction is high. It is an object of the present invention to improve the stability of a cellulose ester solution. Another object of the present invention is to reduce the optical anisotropy of the cellulose ester film.

[0005]

An object of the present invention is to provide a plasticizer for cellulose lower fatty acid ester of the following (1) and (2), a cellulose ester film of the following (3) and a cellulose ester film of the following (4). Has been achieved. (1) A plasticizer for lower fatty acid esters of cellulose comprising glyceride represented by the following formula (I).

[0006]

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In the formula, R ¹ , R ² and R ³ are each an acyl group having 2 to 18 carbon atoms or a hydrogen atom, and at least two of R ¹ , R ² and R ³ have 2 carbon atoms. And at least one of R ¹ , R ² and R ³ is an acyl group having 5 to 18 carbon atoms. (2) The cellulose acetate solution according to (1), wherein at least one of R ¹ , R ² and R ³ is an acyl group having 7 to 18 carbon atoms. (3) A cellulose acetate film comprising a lower fatty acid ester of cellulose, further comprising a glyceride represented by the above formula (I). (4) The lower fatty acid ester of cellulose and the glyceride represented by the above formula (I) are mixed with an organic solvent containing 50% by weight or more of acetone or methyl acetate, thereby swelling the lower fatty acid ester of cellulose in the organic solvent. Step: swelling the mixture at −100 to −10 ° C.
Heating the cooled mixture to 0 to 200 ° C. to prepare a cellulose ester solution in which the lower fatty acid ester of cellulose is dissolved in an organic solvent;
Casting the prepared cellulose ester solution on a support; and evaporating the organic solvent to form a film, thereby producing a cellulose ester film.

[0008]

As described above, conventional glyceride plasticizers have a problem of high hygroscopicity, and thus have not been used for cellulose esters having poor water resistance. However, research by the present inventors has revealed that the problem of high hygroscopicity can be solved by using at least one acyl group of glyceride as an acyl group having 5 or more carbon atoms. As a result of research conducted by the present inventors, it was found that glyceride plasticizers have an effect of stabilizing a cellulose ester solution. Further, it was also found that the glyceride plasticizer has an effect of reducing the optical anisotropy of the cellulose ester (for example, the retardation value in the thickness direction of the cellulose ester film). Therefore, when the glyceride plasticizer of the present invention is used for a lower fatty acid ester of cellulose, the stability of the solution can be improved and the optical anisotropy of the film can be reduced. INDUSTRIAL APPLICABILITY The present invention is particularly effective in a production method such as a cooling dissolution method, which tends to cause problems in solution stability and film optical properties. Glyceride plasticizers
There is also an important feature that it is almost harmless to the human body and the environment.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION [Glyceride Plasticizer] In the present invention, glyceride represented by the following formula (I) is used as a plasticizer for lower fatty acid esters of cellulose.

[0010]

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In the formula (I), R ¹ , R ² and R ³
Is an acyl group having 2 to 18 carbon atoms or a hydrogen atom, at least two of R ¹ , R ² and R ³ are acyl groups having 2 to 18 carbon atoms, and R
^1, at least one of R ² and R ³ are carbon atoms 5
To 18 acyl groups. At least one of R ¹ , R ² and R ³ is preferably an acyl group having 7 to 18 carbon atoms. An acyl group is represented by -CO-R (R is
An aliphatic group, an aromatic group or a heterocyclic group). R is preferably an aliphatic group (alkyl group, substituted alkyl group, alkenyl group, substituted alkenyl group, alkynyl group, substituted alkynyl group) or an aromatic group (aryl group, substituted aryl group). It is more preferably a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an aryl group or a substituted aryl group, further preferably an alkyl group, an alkenyl group or an aryl group, and most preferably an alkyl group.

The alkyl, alkenyl and alkynyl groups preferably have a chain structure rather than a cyclic structure. The chain structure may have a branch. The alkyl part, alkenyl part and alkynyl part of the substituted alkyl group, substituted alkenyl group and substituted alkynyl group are the same as the above-mentioned alkyl group, alkenyl group and alkynyl group. Examples of the substituent of the substituted alkyl group, the substituted alkenyl group and the substituted alkynyl group include an aryl group (eg, phenyl). The aryl moiety of the aryl group and the substituted aryl group is preferably phenyl. Examples of the substituent of the substituted aryl group include an alkyl group. Examples of the acyl group having 5 to 18 carbon atoms include pivaloyl, hexanoyl, heptanoyl, octanoyl, decanoyl, dodecanoyl, hexadecanoyl, octadecanoyl, oleoyl, benzoyl and cinnamoyl. Examples of the acyl group having 2 to 4 carbon atoms include acetyl, propionyl and butyroyl.

The total number of carbon atoms of R ¹ , R ² and R ³ is:
7 to 54. The total number of carbon atoms of R ¹ , R ² and R ³ is preferably 9 to 36, and 11 to 30
Is more preferable. The boiling point of the glyceride represented by the formula (I) is preferably from 280 to 500 ° C, more preferably from 300 to 500 ° C, and most preferably from 300 to 450 ° C. Hereinafter, examples of the glyceride represented by the formula (I) will be shown. The numbers in parentheses are the number of carbon atoms.

{Compound R ¹ R ² R ³ } ＰＬ PL1 hydrogen atom (0) decanoyl (10) decanoyl (10) PL2 pivaloyl (5 Pivaloyl (5) Pivaloyl (5) PL3 Decanoyl (10) Decanoyl (10) Decanoyl (10) PL4 Hexadecanoyl (16) Hexadecanoyl (16) Hexadecanoyl (16) PL5 Acetyl (2) Acetyl (2) Octadecanoyl (18) PL6 acetyl (2) acetyl (2) oleoyl (18) PL7 acetyl (2) acetyl (2) benzoyl (7) PL8 acetyl (2) hydrogen atom (0) octadecanoyl (18) PL9 Pivaloyl (5) Hydrogen atom (0) Oleoyl (18) ─────────────────────────────────── ─

The glyceride represented by the formula (I) can be easily synthesized by an esterification reaction between glycerin and a carboxylic acid or an acid chloride. Alternatively, the glyceride can be synthesized by transesterifying a previously synthesized or commercially available glyceride (eg, glycerin triacetate) with a carboxylic acid. The glyceride represented by the formula (I) is used as a plasticizer by being added to a solution of a lower fatty acid ester of cellulose. The concentration of glyceride in the solution is preferably from 0.2 to 5% by weight, more preferably from 0.5 to 5% by weight, and most preferably from 0.5 to 3% by weight. The amount of the plasticizer in the molded product of the lower fatty acid ester of cellulose (for example, cellulose ester film) is preferably 0.5 to 30% by weight, and more preferably 1 to 25% by weight of the solid content of the molded product. More preferably, 2
Most preferably, it is from 20 to 20% by weight.

Two or more glycerides may be used in combination. Glyceride and another plasticizer can be used in combination. Phosphoric acid esters or carboxylic acid esters are used as other plasticizers. Examples of phosphate esters include:
Includes triphenyl phosphate (TPP), tricresyl phosphate (TCP) and trioctyl phthalate (TOP). As the carboxylic acid ester,
Phthalates and citrates are typical. Examples of phthalic acid esters include dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and dioctyl phthalate (DO).
P) and diethylhexyl phthalate (DEHP). Examples of citrate esters include acetyltriethyl citrate (OACTE) and acetyltributyl citrate (OACTB). Examples of other carboxylic esters include butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and various trimellitic esters. When glyceride is used in combination with another plasticizer, the glyceride is used in an amount of 50% of the total amount of the plasticizer.
Preferably, it is used in a proportion of at least% by weight. The proportion of glyceride is more preferably 70% by weight or more, and further preferably 80% by weight or more.

[Lower fatty acid ester of cellulose] The lower fatty acid means a fatty acid having 6 or less carbon atoms.
The number of carbon atoms is preferably 2 (cellulose acetate), 3 (cellulose propionate) or 4 (cellulose butyrate). Cellulose acetate is more preferable, and cellulose triacetate (acetylation degree: 5
7.0 to 62.5%, preferably 57.5 to 6%
2.5%, more preferably 58.0 to 62.5%)
Is most preferred. The degree of acetylation of cellulose acetate follows the measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method for cellulose acetate and the like). Mixed fatty acid esters of cellulose such as cellulose acetate propionate and cellulose acetate butyrate may be used. The viscosity average degree of polymerization (DP) of the cellulose ester is preferably from 150 to 500, most preferably from 250 to 360. The cellulose ester preferably has a narrow molecular weight distribution of Mw / Mn (Mw is a weight average molecular weight, Mn is a number average molecular weight) determined by gel permeation chromatography. Specific values of Mw / Mn include:
It is preferably 0 to 1.7, and 1.3 to 1.6.
More preferably, it is 5 and most preferably 1.4 to 1.6.

[Organic Solvent] The cellulose ester and the glyceride plasticizer are dissolved in an organic solvent to prepare a solution (dope). Organic solvents include ethers having 3 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, esters having 3 to 12 carbon atoms, and 1 to 6 carbon atoms.
It is preferable to include a solvent selected from halogenated hydrocarbons. Ethers, ketones and esters may have a cyclic structure. Functional groups of ether, ketone and ester (i.e., -O-, -CO- and -COO
A compound having two or more of any one of-) can also be used as the organic solvent. The organic solvent may have another functional group such as an alcoholic hydroxyl group. In the case of an organic solvent having two or more types of functional groups, the number of carbon atoms may be within the specified range of the compound having any one of the functional groups.

Examples of the ethers having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolan, tetrahydrofuran, anisole and phenetole. Examples of the ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclohexanone and methylcyclohexanone. Examples of the esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate. Examples of the organic solvent having two or more types of functional groups include
Includes 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol. As the halogenated hydrocarbon having 1 to 6 carbon atoms, methylene chloride is typical. Technically, halogenated hydrocarbons such as methylene chloride can be used without any problem, but from the viewpoint of the global environment and work environment, it is preferable that the organic solvent contains substantially no halogenated hydrocarbons.
“Substantially free” means that the proportion of halogenated hydrocarbon in the organic solvent is less than 5% by weight (preferably less than 2% by weight). Further, it is preferable that no halogenated hydrocarbon such as methylene chloride is detected at all from the produced cellulose acetate film.

Particularly preferred organic solvents are mixed solvents of three different solvents, wherein the first solvent is a ketone having 3 to 12 carbon atoms and a ketone having 3 to 12 carbon atoms.
Wherein the second solvent is selected from linear monohydric alcohols having 1 to 4 carbon atoms, and the third solvent is selected from branched or cyclic alcohols having 3 to 8 carbon atoms. It is. The ketone and the ester of the first solvent are as described above. The second solvent is selected from linear monohydric alcohols having 1 to 5 carbon atoms. The hydroxyl group of the alcohol may be bonded to the terminal of the hydrocarbon straight chain (primary alcohol) or may be bonded in the middle (secondary alcohol). The second solvent is specifically methanol, ethanol, 1-propanol, 2-
Propanol, 1-butanol, 2-butanol, 1-
It is selected from pentanol, 2-pentanol and 3-pentanol. The number of carbon atoms of the linear monohydric alcohol is preferably 1 to 4, more preferably 1 to 3, and most preferably 1 or 2. Ethanol is particularly preferably used.

The third solvent is selected from a branched or cyclic alcohol having 3 to 8 carbon atoms. Preferably, the alcohol is monovalent. Preferably, the hydrocarbon portion of the alcohol is a saturated aliphatic hydrocarbon. The hydroxyl group of the alcohol may be any of primary to tertiary. Examples of branched or cyclic alcohols having 3 to 8 carbon atoms include isopropanol, isobutanol, t-
Includes butanol, isopentanol, isohexanol and cyclohexanol.

The first solvent is preferably contained in the mixed solvent in an amount of 50 to 95% by weight, more preferably 60 to 92% by weight, and more preferably 65 to 90% by weight.
More preferably, the content is most preferably 70 to 88% by weight. The second solvent is preferably contained at 1 to 15% by weight, more preferably at 2 to 15% by weight, more preferably at 3 to 10% by weight, and more preferably at 4 to 22% by weight. Most preferred. The third solvent is preferably contained in an amount of 1 to 20% by weight, more preferably 2 to 15% by weight, and most preferably 3 to 15% by weight. Further, another organic solvent may be used in combination to form a mixed solvent of four or more kinds.

[Preparation of Solution (Cooling Dissolution Method)] In the present invention, it is preferable to form a solution by dissolving the cellulose ester and the glyceride plasticizer in the above organic solvent by the cooling dissolution method. In preparing the solution,
First, the cellulose ester is slowly added to the organic solvent at room temperature with stirring. At this stage, the cellulose ester generally swells but does not dissolve in the organic solvent.
In addition, even if it is a solvent which can dissolve cellulose ester at room temperature, according to the cooling dissolution method, there is an effect that a uniform solution can be obtained quickly. It is preferable to adjust the amount of the cellulose ester so that the mixture contains 10 to 40% by weight of the mixture. The amount of cellulose ester is 10 to 3
More preferably, it is 0% by weight. Further, an optional additive described below may be added to the mixture.

Next, the mixture is cooled to -100 to -10 ° C (preferably -80 to -10 ° C, more preferably -50 to -10 ° C).
To -20 ° C, most preferably -50 to -30 ° C). The cooling can be performed, for example, in a dry ice / methanol bath (−75 ° C.) or a cooled diethylene glycol solution (−30 to −20 ° C.). Upon cooling in this manner, the mixture of the cellulose ester, glyceride plasticizer and organic solvent solidifies. The cooling rate is preferably 4 ° C./min or more, more preferably 8 ° C./min or more, and most preferably 12 ° C./min or more. The cooling rate is preferably as high as possible, but 10,000 ° C. /
Seconds is the theoretical upper limit, 1000 ° C./sec is the technical upper limit, and 100 ° C./sec is the practical upper limit.
The cooling rate is a value obtained by dividing the difference between the temperature at which the cooling is started and the final cooling temperature by the time from when the cooling is started to when the temperature reaches the final cooling temperature.

Further, the temperature is raised to 0 to 200 ° C (preferably 0 to 150 ° C, more preferably 0 to 120 ° C,
When heated to the temperature of 0 to 50 ° C., the cellulose ester dissolves in the organic solvent. The temperature may be raised only by leaving it at room temperature or may be heated in a warm bath. The heating rate is preferably 4 ° C./min or more, more preferably 8 ° C./min or more, and most preferably 12 ° C./min or more. The heating rate is preferably as high as possible, but the theoretical upper limit is 10,000 ° C./sec.
C / sec is a technical upper limit, and 100 C / sec is a practical upper limit. Note that the heating rate is a value obtained by dividing the difference between the temperature at which heating is started and the final heating temperature by the time from when the heating is started until the final heating temperature is reached. . As described above, a uniform solution is obtained. In addition,
If the dissolution is insufficient, the operation of cooling and heating may be repeated. Whether or not the dissolution is sufficient can be determined only by visually observing the appearance of the solution. In the cooling dissolution method, it is preferable to use a closed container in order to avoid water contamination due to condensation during cooling. In addition, in the cooling and heating operation, if the pressure is increased during cooling and the pressure is reduced during heating, the dissolution time can be shortened. In order to perform pressurization and decompression, it is desirable to use a pressure-resistant container.

[Production of Film] A cellulose ester film is produced from the prepared cellulose ester solution. Specifically, the solution is used as a dope in a solvent casting method. The dope is cast on a drum or band and the solvent is evaporated to form a film. The concentration of the dope before casting is preferably adjusted so that the solid content is 18 to 35%. It is preferable that the surface of the drum or the band is finished in a mirror state. The casting and drying methods in the solvent casting method are described in U.S. Pat. Nos. 2,336,310 and 2,367,603.
Nos. 2492078, 2492977, 24
No. 92978, No. 2607704, No. 2739069
Nos. 2739070, British Patent Nos. 640731 and 736892, Japanese Patent Publication No. 45-4554,
JP-A-49-5614, JP-A-60-176834, JP-A-60-203430 and JP-A-62-115035.

The dope is preferably cast on a drum or band having a surface temperature of 10 ° C. or less. After casting, it is preferable to dry by blowing against the wind for 2 seconds. The obtained film can be peeled off from the drum or band, and further dried with high-temperature air whose temperature is gradually changed from 100 to 160 ° C. to evaporate the residual solvent. The above method is described in JP-B-5-17844. According to this method, the time from casting to stripping can be reduced. In order to carry out this method, it is necessary that the dope gels at the surface temperature of the drum or band during casting. The solution (dope) prepared according to the present invention satisfies this condition. The film to be manufactured preferably has a thickness of 5 to 500 μm,
The thickness is more preferably 0 to 200 μm, and most preferably 60 to 150 μm.

The cellulose ester film may be added with a deterioration inhibitor (eg, an antioxidant, a peroxide decomposer, a radical inhibitor, a metal deactivator, an acid scavenger, an amine) or an ultraviolet inhibitor. Good. Regarding the deterioration inhibitor, see
-199201, 5-1907073, 5-1
No. 94789, No. 5-271471, No. 6-1078
No. 54 describes each of them. The addition amount of the deterioration inhibitor
It is preferably 0.01 to 1% by weight, more preferably 0.1 to 0.2% by weight of the solution (dope) to be prepared.

The cellulose ester film can be preferably used as a support for a silver halide photographic light-sensitive material. In a liquid crystal display device, a cellulose ester film can be advantageously used also as a protective film for a polarizing plate or a support for an optical compensation sheet. The cellulose ester film obtained according to the present invention has a T
This is particularly effective in an FT type liquid crystal display device. The cellulose ester film using the glyceride plasticizer of the present invention is characterized by having a low retardation value in the thickness direction even when produced by a cooling dissolution method. The retardation value in the thickness direction is preferably from 0 to 100 nm, more preferably from 0 to 80 nm, and most preferably from 0 to 60 nm.

[0030]

EXAMPLES In the examples, the physical properties of the cellulose ester solution and the cellulose ester film were evaluated as follows.

(1) Solution Stability The obtained solution was observed while standing at room temperature (23 ° C.) and evaluated by the following three grades of A, B and C. A: Even after 10 days, transparency and uniformity are maintained, and good solubility and solution stability are exhibited. B: At the end of stirring, the mixture exhibits transparency and uniformity and exhibits good solubility, but after a lapse of one day, phase separation occurs, resulting in a non-uniform state. C: Immediately after the completion of stirring, a non-uniform slurry is formed, and a transparent and uniform solution state is not exhibited.

(2) Judgment of presence or absence of gelation of the solution The change point of the coefficient A in the following Andrade equation was determined by a viscometer (manufactured by HAAKE). Gelation was judged from the change point and the attained viscosity. Rotor: sv-DIN Shear rate: 0.1 (1 / sec) Cooling rate: 0.5 ° C./min η = Aexp (B / T) In the formula, T is the measurement temperature, and A and B are the states of the polymer, respectively. Is an arbitrary constant determined by The presence or absence of gelation can be determined by the presence or absence of a changing point of the coefficient A (whether or not the graph of viscosity and temperature has an inflection point).

(3) Peelability of Film The dope was cast on a support at -5 ° C. in the form of a film, and the properties of the film when peeled off from the support were evaluated. The peelability of the film was classified into the following two stages. A: What can be peeled off within 20 seconds B: What has peeling residue even after 60 seconds or more

(4) Elastic Modulus of Film A sample having a length of 100 mm and a width of 10 mm was subjected to ISO 1184
According to the standard of 1983, the elastic modulus (kg / mm) was measured at an initial sample length of 50 mm and a tensile speed of 20 mm / min.
² ) Asked.

(5) Film tearing load A sample cut to 50 mn × 64 mm was subjected to ISO 638.
The tear load (kg) required for tearing was determined according to the standard of 3 / 2-1983.

(6) The sample cut out to 120 mn in the number of times the film can be folded was subjected to ISO 8776 / 2-1.
According to the standard of 988, the number of reciprocations until cutting by bending was determined.

(7) Moisture / heat resistance of the film 1 g of the sample is folded and put into a 15 ml glass bottle.
After humidity control at a temperature of 90 ° C. and a relative humidity of 100%, the container was sealed. This was aged at 90 ° C. and taken out after 200 hours. The state of the film was visually checked, and the following judgment was made. A: No particular abnormality is observed. B: Decomposition odor or shape change due to decomposition is observed.

(8) Film retardation (R
e) Value A value measured using an ellipsometer (Analysis analyzer AEP-100: manufactured by Shimadzu Corporation) at a wavelength of 632.8 nm from a direction perpendicular to the film surface and a retardation measured similarly while tilting the film surface. From the extrapolated value of the value, the retardation value (n
m) is calculated. Formula (1) Retardation value in the thickness direction = [(nx + ny) / 2
−nz] × d (nm) where nx is the refractive index in the x direction (horizontal direction) in the film plane, ny is the refractive index in the y direction (vertical direction) in the film plane, and nz is the film. The index of refraction in the direction perpendicular to the plane, and d is the thickness of the film.

(9) Alkali Hydrolytic Property of Film Half of a 10 cm × 10 cm film is placed at 60 ° C., 2N
It was immersed in an aqueous sodium hydroxide solution for 2 minutes, washed with water, and then dried at 100 ° C. for 10 minutes. The part immersed in sodium hydroxide was visually observed and determined as follows. A: No whitening is observed B: Whitening is slightly observed C: Whitening is considerably observed D: Whitening is extremely observed

Example 1 A mixture having the following composition was stirred at room temperature. At room temperature, the cellulose acetate did not dissolve but swelled in the mixed solvent to form a slurry.

組成 Swelled mixture composition──────── １５ 15 weight of cellulose acetate (average acetylation degree: 60.9%, viscosity average polymerization degree: 299) Part Plasticizer shown in Table 1 2.5 parts by weight Methyl acetate (first organic solvent) 67.5 parts by weight Ethanol (second organic solvent) 10 parts by weight Cyclohexanol (third organic solvent) 5 parts by weight 2- ( 2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole (UV absorber a) 0.075 parts by weight 2- (2'-hydroxy-3', 5'- Di-t-amylphenyl) benzotriazole (ultraviolet absorber b) 0.15 parts by weight colloidal silica 006 parts by weight ────────────────────────────────────

Next, the swelling mixture was placed in a container having a double structure. While stirring the mixture slowly, a dry ice / methanol mixture was poured into the outer jacket as a refrigerant. Thereby, the mixture in the inner container was cooled to -70 ° C (cooling rate: 8 ° C / min). Cooling with the refrigerant was continued until the mixture was uniformly cooled and solidified (30 minutes). The refrigerant in the jacket outside the vessel was removed and warm water was instead poured into the jacket. At the stage where the sol formation of the content has progressed to some extent, stirring of the content was started. In this way, the mixture was heated to room temperature (heating rate: 8 ° C./min).
Further, the above cooling and heating operations were repeated once.

The obtained solution (dope) was cast using a band casting machine having an effective length of 6 m so that the dry film thickness became 100 μm. The band temperature was 0 ° C. For drying,
After being exposed to the wind for 2 seconds, the film was peeled off from the band, and further heated at 100 ° C. for 3 minutes, 130 ° C. for 5 minutes, and 160 ° C.
The film was dried stepwise while fixing the edge of the film for 5 minutes to evaporate the remaining solvent. Thus, a cellulose acetate film was produced. About the solution and the film obtained as described above, the above (1) to (9)
Was tested for physical properties. The results are shown in Table 1.

[0044]

[Table 1] Table 1 試 料 Sample test item number Plasticizer ( 1) (2) (3) (4) (5) (6) (7) (8) (9) ──────────────────────── ──────────── 10 None * A Available A 183 21 75 A 175 D ────────────────────────── １１ 11 PLx A With A 337 27 168 A 22 D 12 PLy A With A 340 29 175 A 57 B ────────────────── ────────────────── 13 PL2 A Yes A 339 28 182 A 27 A14 PL7 A Yes A 320 30 171 A31 A15 PL8 A Yes A 342 33 169 A 32 A 16 PL9 A Yes A 336 31 182 A 29 A ───────────── １７ 17 TPP B Yes B 283 24 141 A 162 A 18 TCP A Yes A 335 29 153 A 158 A 19 BDP A No A 329 31 172 A 155 B20 TOPA No A 337 29 129 B 143 A 21 DMP B No B 289 33 131 B 165 C22 DEP B Yes B 305 32 122 B 162 B23 DBPB Yes B 311 30 161 B163 ────────────────────────────────────

(Note) None *: 2.5 parts by weight of plasticizer was not added, and 70 parts by weight of ethyl acetate was used. PLx: glycerin triacetate PLy: glycerin tributyrate TPP: triphenyl phosphate TCP: tricresyl phosphate BDP : Biphenyl diphenyl phosphate TOP: trioctyl phosphate DMP: dimethyl phthalate DEP: diethyl phthalate DBP: dibutyl phthalate

Example 2 Sample No. 13 of Example 1 above
An optical compensatory sheet was prepared using Nos. To 16 as a support (a method similar to Example 1 in JP-A-7-33433). On one side of the film, a gelatin layer (thickness: 0.
1 μm), and then an alkyl-modified polyvinyl alcohol film was provided on the gelatin layer, and rubbed to form an alignment film. Further, the discotic compound and the photopolymerization initiator were applied on the alignment film, and the aligned discotic compound was polymerized by light irradiation to obtain an optical compensation sheet. The obtained optical compensation sheet had excellent viewing angles in the right, left, up, and down directions. Separately, an optical compensation sheet was obtained in the same manner as described above, using Sample No. 23 as a support. The obtained optical compensatory sheet was inferior to the optical compensatory sheet using the above-described film of the present invention in the viewing angle in both the left and right and upper and lower directions.

Example 3 Sample No. 13 of Example 1 above
(Example 1 of JP-A-4-73736 (back-side layer) and Example 1 of JP-A-7-287345 (emulsion side) Layer) and similar methods). On one side (back side) of the film, a first protective layer containing triacetyl cellulose and a conductive material and a second protective layer containing diacetyl cellulose, silica fine particles, and dimethyl silicon were sequentially provided. On the other side (emulsion side) of the film, a gelatin subbing layer, an antihalation layer, an intermediate layer containing a silver iodobromide emulsion and latex, a low-speed red-sensitive emulsion layer, a medium-speed red-sensitive emulsion layer, and a high-speed red-sensitive emulsion Layer, intermediate layer containing solid dispersion and latex, low-speed green-sensitive emulsion layer, medium-speed green-sensitive emulsion layer,
A high-sensitivity green-sensitive emulsion layer, a yellow filter layer, a low-sensitivity blue-sensitive emulsion layer, a medium-sensitivity blue-sensitive emulsion layer, a high-sensitivity blue-sensitive emulsion layer, a first protective layer containing an ultraviolet absorber, and a first layer containing a silver iodobromide emulsion. Two protective layers were sequentially provided to obtain a color negative type silver halide photographic material. When the obtained silver halide photographic material was examined for its elastic modulus, tear strength, number of foldings and surface condition of the support, excellent results were obtained. No transfer (bleed-out) of the plasticizer to the surface of the support was observed. Separately, using Sample No. 23 as a support, a silver halide photographic material was obtained in the same manner as described above. The elastic modulus, tear strength, folding endurance and support surface condition of the obtained silver halide photographic material are as follows:
It was inferior to the silver halide photographic material using the above-mentioned film of the present invention.

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[Procedure amendment]

[Submission date] September 2, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 2

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

In the formula, R ¹ , R ² and R ³ are each an acyl group having 2 to 18 carbon atoms or a hydrogen atom, and at least two of R ¹ , R ² and R ³ have 2 carbon atoms. To R 18, and at least one of R ¹ , R ² and R ³ is an acyl group having 5 to 18 carbon atoms. (2) The plasticizer for lower fatty acid esters of cellulose according to (1), wherein at least one of R ¹ , R ² and R ³ is an acyl group having 7 to 18 carbon atoms. (3) A cellulose ester film containing a lower fatty acid ester of cellulose, further comprising a glyceride represented by the above formula (I).
Ester film. (4) The lower fatty acid ester of cellulose and the glyceride represented by the above formula (I) are mixed with an organic solvent containing 50% by weight or more of acetone or methyl acetate, thereby swelling the lower fatty acid ester of cellulose in the organic solvent. Step: swelling the mixture at −100 to −10 ° C.
Heating the cooled mixture to 0 to 200 ° C. to prepare a cellulose ester solution in which the lower fatty acid ester of cellulose is dissolved in an organic solvent;
Casting the prepared cellulose ester solution on a support; and evaporating the organic solvent to form a film, thereby producing a cellulose ester film.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0027

[Correction method] Change

[Correction contents]

The dope is preferably cast on a drum or band having a surface temperature of 10 ° C. or less. After casting, it is preferably dried with a 2 seconds or more on wind. The obtained film can be peeled off from the drum or band, and further dried with high-temperature air whose temperature is gradually changed from 100 to 160 ° C. to evaporate the residual solvent. The above method is described in JP-B-5-17844. According to this method, the time from casting to stripping can be reduced. In order to carry out this method, it is necessary that the dope gels at the surface temperature of the drum or band during casting. The solution (dope) prepared according to the present invention satisfies this condition. The film to be manufactured preferably has a thickness of 5 to 500 μm,
The thickness is more preferably 0 to 200 μm, and most preferably 60 to 150 μm.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction contents]

(6) The sample cut out to 120 mn in the number of times the film can be folded was subjected to ISO 8776 / 2-1.
In accordance with 988 standards, it was determined the number of round-trips of up to bending thus cutting.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

Example 1 A mixture having the following composition was stirred at room temperature. At room temperature, the cellulose acetate did not dissolve but swelled in the mixed solvent to form a slurry.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction contents]

Example 2 Sample No. 13 of Example 1 above
An optical compensatory sheet was prepared using Nos. To 16 as a support (a method similar to Example 1 in JP-A- 7-333433 ). On one side of the film, a gelatin layer (thickness: 0.
1 μm), and then an alkyl-modified polyvinyl alcohol film was provided on the gelatin layer, and rubbed to form an alignment film. Further, the discotic compound and the photopolymerization initiator were applied on the alignment film, and the aligned discotic compound was polymerized by light irradiation to obtain an optical compensation sheet. The obtained optical compensation sheet had excellent viewing angles in the right, left, up, and down directions. Separately, an optical compensation sheet was obtained in the same manner as described above, using Sample No. 23 as a support. The obtained optical compensatory sheet was inferior to the optical compensatory sheet using the above-described film of the present invention in the viewing angle in both the left and right and upper and lower directions.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0047

[Correction method] Change

[Correction contents]

Example 3 Sample No. 13 of Example 1 above
(Example 1 of JP-A-4-73736 (back side layer) and Example 1 of JP-A-7-287345 (emulsion side) Layer) and similar methods). On one side (back side) of the film, a first protective layer containing triacetyl cellulose and a conductive material and a second protective layer containing diacetyl cellulose, silica fine particles, and dimethyl silicon were sequentially provided. On the other side (emulsion side) of the film, a gelatin subbing layer, an antihalation layer, an intermediate layer containing a silver iodobromide emulsion and latex, a low-speed red-sensitive emulsion layer, a medium-speed red-sensitive emulsion layer, and a high-speed red-sensitive emulsion Layer, an intermediate layer containing a solid disperse dye and latex, a low-speed green-sensitive emulsion layer, a medium-speed green-sensitive emulsion layer,
A high-sensitivity green-sensitive emulsion layer, a yellow filter layer, a low-sensitivity blue-sensitive emulsion layer, a medium-sensitivity blue-sensitive emulsion layer, a high-sensitivity blue-sensitive emulsion layer, a first protective layer containing an ultraviolet absorber, and a first layer containing a silver iodobromide emulsion. Two protective layers were sequentially provided to obtain a color negative type silver halide photographic material. When the obtained silver halide photographic material was examined for its elastic modulus, tear strength, number of foldings and surface condition of the support, excellent results were obtained. No transfer (bleed-out) of the plasticizer to the surface of the support was observed. Separately, using Sample No. 23 as a support, a silver halide photographic material was obtained in the same manner as described above. The elastic modulus, tear strength, folding endurance and support surface condition of the obtained silver halide photographic material are as follows:
It was inferior to the silver halide photographic material using the above-mentioned film of the present invention.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 7:00

Claims (4)

[Claims] 1. A plasticizer for a lower fatty acid ester of cellulose comprising glyceride represented by the following formula (I). Embedded image Wherein, R ^1, R ² and R ³ is an acyl group or a hydrogen atom of the respective number of carbon atoms 2 to 18, R ^1, R
^At least two of R ² and R ³ have 2 to 1 carbon atoms;
And at least one of R ¹ , R ² and R ³ is an acyl group having 5 to 18 carbon atoms. 2. The cellulose acetate solution according to claim 1, wherein at least one of R ¹ , R ² and R ³ is an acyl group having 7 to 18 carbon atoms. 3. A cellulose ester film containing a lower fatty acid ester of cellulose, further comprising a glyceride represented by the following formula (I). Embedded image Wherein, R ^1, R ² and R ³ is an acyl group or a hydrogen atom of the respective number of carbon atoms 2 to 18, R ^1, R
^At least two of R ² and R ³ have 2 to 1 carbon atoms;
And at least one of R ¹ , R ² and R ³ is an acyl group having 5 to 18 carbon atoms. 4. A lower fatty acid ester of cellulose and a glyceride represented by the following formula (I) are mixed with an organic solvent containing 50% by weight or more of acetone or methyl acetate,
A step of swelling the lower fatty acid ester of cellulose in an organic solvent thereby;
Cooling to 10 ° C .;
C. to prepare a cellulose ester solution in which the lower fatty acid ester of cellulose is dissolved in an organic solvent; casting the prepared cellulose ester solution on a support; and evaporating the organic solvent A method for producing a cellulose ester film, comprising a step of forming a film. Embedded image Wherein, R ^1, R ² and R ³ is an acyl group or a hydrogen atom of the respective number of carbon atoms 2 to 18, R ^1, R
^At least two of R ² and R ³ have 2 to 1 carbon atoms;
And at least one of R ¹ , R ² and R ³ is an acyl group having 5 to 18 carbon atoms.