JP2002265637A - Cellulose ester film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cellulose ester film having an excellent planar state from a solution prepared by dissolving a cellulose ester in an organic solvent except a chlorine-based organic solvent. SOLUTION: This cellulose ester film is prepared from a mixed solution comprising a cellulose ester which has the molar ratio of mannose/xylose of 0.35 to 3.0 and a degree of substitution satisfying (I) 2.6<=A+B<=3.0, (II) 2.0<=A<=3.0 and (III) 0<=B<=0.8 (A is a degree of substitution of acetyl group; B is a degree of substitution of a 3-22C acyl group), a mold release agent containing an acid having <=4 pKa, methyl acetate, a 3-6C ketone and a 1-4C alcohol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cellulose ester film solution useful for a silver halide photographic material or a liquid crystal image display device, and a cellulose ester film formed therefrom.

[0002]

2. Description of the Related Art Conventionally, a chlorine-based organic solvent such as methylene chloride has been used as an organic solvent for a cellulose ester solution used in producing cellulose acetate used for a silver halide photographic material or a liquid crystal image display device. It is used. Methylene chloride (boiling point: 40 ° C.) has been conventionally used as a good solvent for cellulose esters, and is preferably used because it has a low boiling point in the film-forming and drying steps of the production process, so that it can be easily dried. 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 a cellulose ester other than methylene chloride has been made. Acetone (having a boiling point of 56
° C), methyl acetate (boiling point 56 ° C), tetrahydrofuran (boiling point 65 ° C), 1,3-dioxolane (boiling point 75
° C) and 1,4-dioxane (boiling point 101 ° C). 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
Etc. are described in Makromol. chem. In volume 143, page 105 (1971), cellulose triacetate (degree of acetylation: 60.1% to 61.3%) was added at -80 ° C in acetone.
To -70 ° C and then warmed to 0.
It reports that 5 to 5% by weight of dilute solution is obtained. The method of dissolving the cellulose ester at such 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, in each of JP-A-9-95538, JP-A-9-95544 and JP-A-9-95557, the cellulose ester is dissolved by a cooling dissolution method using a non-halogen solvent against the background of the above technology. Is disclosed. Japanese Patent Application Laid-Open No. H11-60752 proposes to improve by adding a fluoroalcohol to a cellulose ester solution. Problems occur.

On the other hand, JP-A-10-130301 discloses that mannose / xylose = 0.
Α-cellulose content 90 to 35 to 3.0 (molar ratio)
By acetylating low-purity pulp of 97% by mass and a total content of mannose and xylose of 2 to 6% by mol to produce a cellulose ester having an average degree of acetylation of 58 to 62.5%, it is supported in the casting method. It has been proposed that the removability of the film from the body can be improved. According to this method, it was recognized that it was effective with respect to the conventional solvent, methylene chloride. Further improvements were desired.

[0006] Generally, cellulose esters contain water and are known to be 2.5 to 5% by mass. In a conventional methylene chloride solvent, the cellulose ester is often converted into a solution while containing water, and in such a case, there is no particular problem for use as a light-sensitive material. However, when an environmentally friendly non-halogen solvent is used, when the cellulose ester contains water, a failure occurs in that the surface state is deteriorated. In particular, when a cellulose ester film is used as a protective film for an electronic material, further improvement has been desired in terms of its surface.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to prepare a solution of a conventional cellulose ester in a non-chlorine-based organic solvent by imparting excellent solubility to the solution and casting it. It is an object of the present invention to provide a cellulose cellulose film having good take-up properties and excellent surface condition of the obtained film.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a neutral sugar component having a mannose / xylose molar ratio of 0.35 to 3.0 and the degree of substitution of cellulose with hydroxyl groups by the following formula: Cellulose esters having I) to (III),
A mixture of a release agent having an acid of pKa4 or less, methyl acetate, a ketone having 3 to 6 carbon atoms and an alcohol having 1 to 4 carbon atoms is cooled to -100 to -10C or /
And a cellulose ester film produced by casting and drying from a cellulose ester solution obtained by heating at a high temperature and a high pressure of 70 to 200 ° C. and 0.3 to 30 MPa. (I) 2.6 ≦ A + B ≦ 3.0 (II) 2.0 ≦ A ≦ 3.0 (III) 0 ≦ B ≦ 0.8 [wherein A and B are substituted with hydroxyl groups of cellulose. A represents the degree of substitution of an acetyl group, and B represents the degree of substitution of an acyl group having 3 to 22 carbon atoms.]

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The cellulose ester of the present invention comprises
The degree of substitution of cellulose with a hydroxyl group is represented by the following formulas (I) to (III)
Satisfies all of (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 acyl substituted with a hydroxyl group of cellulose. A represents the degree of substitution of an acetyl group, and B represents 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, with the maximum degree of substitution being 3.0. Cellulose triacetate generally has a degree of substitution of A of 2.6 to 3.0 (in this case, the maximum of unsubstituted hydroxyl groups is 0.4), and the case of B = 0 is cellulose triacetate. Cellulose esters are cellulose triacetate in which all acyl groups are acetyl groups, and 2.0% in acetyl groups.
As described above, the acyl group having 3 to 22 carbon atoms is preferably 0.8 or less, and the unsubstituted hydroxyl group is preferably 0.4 or less. 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. In addition, the substitution degree is acetic acid to be substituted for the hydroxyl group of the cellulose or 3 carbon atoms.
The degree of binding of ~ 22 fatty acids is measured and obtained by calculation. The measurement can be performed according to ASTM D-817-91.

When the acyl groups are all acetyl groups, the substitution degree of the hydroxyl groups is usually represented by the degree of acetylation. That is, the average degree of acetylation in cellulose acetate is 58% to 6 depending on the use and characteristics.
2.5% (average degree of acetyl group substitution 2.64 to 3.0)
The range of the degree is preferable. More preferably 59-62%,
More preferably, it is about 60 to 61%. Here, the degree of acetylation means the amount of bound acetic acid, and refers to the mass percentage of bound acetic acid per unit mass of cellulose, and ASTM: D-817.
It can be measured according to the method for measuring the degree of acetylation of -91 (test method for cellulose acetate or the like). Specifically, 1.9 g of dried cellulose acetate was precisely weighed, and a mixed solvent of acetone and dimethyl sulfoxide (volume ratio: 4:
1) After dissolving in 150 ml, 30 ml of a 1N aqueous sodium hydroxide solution is added and saponified at 25 ° C. for 2 hours. Add phenolphthalein as an indicator and titrate excess sodium hydroxide with 1 N sulfuric acid (concentration factor: F). Further, it can be determined by performing a blank test in the same manner as described above and calculating the degree of acetylation according to the following formula. Degree of acetylation (%) = [6.5 × (BA) × F] / W (where A is the titer of 1N sulfuric acid in the sample (ml), B is the titration of 1N sulfuric acid in the blank test) Amount (ml), F is 1N
The sulfuric acid concentration factor, W indicates the mass of the sample).

Further, the substitution degree of the hydroxyl group at the 6-position of the cellulose ester is preferably larger than that at the 2- and 3-positions. In general, the 2, 3, and 6 hydroxyl groups are not evenly distributed to 1/3 of the total degree of substitution, and the degree of substitution of the 6-position hydroxyl group tends to decrease. Therefore, the hydroxyl group at the 6-position is preferably substituted with an acyl group in an amount of 32% or more, more preferably 33% or more, and particularly preferably 34% or more with respect to the total degree of substitution. The degree of substitution at each position can be determined by NMR. Further, the 6-position hydroxyl group is preferably an acyl group having 3 or more carbon atoms other than an acetyl group, and is a propionyl group, a butyroyl group,
Valeroyl, benzoyl, and acryloyl groups can be used. The acyl group of the cellulose ester may be an aliphatic acyl group or an aromatic acyl group. These are, for example, alkylcarbonyl esters, alkenylcarbonyl esters or aromatic carbonyl esters of cellulose, and aromatic alkylcarbonyl esters, each of which may have a further substituted group, and an ester group having a total carbon number of 22 or less. Is preferred. As these preferred cellulose esters, acyl groups having a total carbon number of 22 or less in the ester portion (eg, acetyl, propionyl, butyroyl, barrel, heptanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl,
Hexadecanoyl, octadecanoyl), alkenylcarbonyl groups (eg, acryloyl, methacryloyl), arylcarbonyl groups (eg, benzoyl, naphthaloyl), and cinnamoyl groups. Cellulose acetate, cellulose acetate propionate,
Cellulose acetate butyrate, cellulose acetate stearate and cellulose acetate benzoate are preferred.

[0012] Cellulose acetate is preferred. Photographic grade cellulose acetate is particularly preferred, and commercially available photographic grades can be obtained with satisfactory qualities such as viscosity average polymerization degree and substitution degree. As a manufacturer of photographic grade cellulose acetate, Daicel Chemical Industries, Ltd. (eg, LT-20, 30, 40, 50,
70, 35, 55, 105), Eastman Kodak Company (eg, CAB-551-0.01, CAB-551)
0.02, CAB-500-5, CAB-381-0.
5, CAB-381-02, CAB-381-20, C
AB-321-0.2, CAP-504-0.2, CA
P-482-20, CA-398-3), Coatles Co., Ltd., Hoechst Co., etc., and any of them can use photographic grade cellulose acetate. In the cellulose ester of the present invention, mannose / xylose (molar ratio)
= 0.35 / 1 to 3.0 / 1. More preferably, mannose / xylose (molar ratio) = 0.35 / 1 to 2.
5/1, more preferably mannose / xylose (molar ratio) = 0.35 / 1 to 2/1. In particular, mannose / xylose (molar ratio) = 0.5 / 1 to 1.5 / 1,
Preferably it is 0.7 / 1 to 1.3 / 1. The ratio of mannose to xylose substantially corresponds to the component ratio of the raw pulp of cellulose acetate.

In the cellulose ester of the present invention, the total content of mannose and xylose is from 1 to 5
Mol%, more preferably 1.6 to 4 mol%, still more preferably 2 to 3.5 mol%, particularly 2.5 to 3.5 mol%.
Mol%. "Mannose" and "Xylose"
Is the main constituent sugar of hemicellulose (xylan, glucomannan) contained in pulp. Raw pulp and constituent sugar components of the obtained cellulose ester are described in detail in JP-A-10-130310, and can be determined according to the method.

A cellulose ester can be produced by acetylating a specific pulp. That is, the ratio (molar ratio) between mannose and xylose = 0.
35/1 to 3.0 / 1 [preferably 0.5 / 1 to 3 /
1, more preferably 0.7 / 1 to 2/1]. Such pulp contains at least pulp mainly containing softwood pulp, and if necessary, cotton linter pulp or hardwood pulp may be mixed with softwood pulp. The ratio of the other pulp to the softwood pulp is 10 to 300 parts by mass of linter pulp and / or hardwood pulp, more preferably 10 to 200 parts by mass, and still more preferably 10 to 100 parts by mass of softwood pulp.
It can be selected from the range of 100 parts by mass.

The cellulose ester can be produced by a conventional method, for example, a sulfuric acid catalyst method, an acetic acid method, or a methylene chloride method. Cellulose ester is usually activated after pulp (cellulose) is treated with acetic acid (activation step),
It is produced by preparing triacetate with acetic anhydride using a sulfuric acid catalyst (acetylation step) and adjusting the degree of acetylation by saponification (hydrolysis) (saponification step). The activation step can be performed by, for example, treating pulp (cellulose) by spraying with acetic acid or hydrous acetic acid, or immersing in acetic acid or hydrous acetic acid. 10 to 100 parts by mass, preferably 20 to 80 parts by mass, more preferably 30 to 6 parts by mass with respect to parts by mass.
It is about 0 parts by mass. The amount of acetic anhydride to be used in the acetylation step can be selected within the above range of the acetylation degree.
Parts by mass, preferably 240 to 290 parts by mass, more preferably about 250 to 280 parts by mass. In the acetylation step, acetic acid is used as a solvent, and the amount of acetic acid used is about 200 to 700 parts by weight, preferably about 300 to 600 parts by weight, more preferably about 350 to 500 parts by weight, based on 100 parts by weight of pulp (cellulose). is there. The amount of sulfuric acid used as a catalyst is 1 to 100 parts by mass of cellulose.
The amount is 15 parts by mass, preferably 5 to 15 parts by mass, particularly preferably about 5 to 10 parts by mass. Saponification can be performed, for example, at a temperature of about 50 to 70 ° C. Further, it is useful to treat the produced cellulose acetate with an oxidizing agent after an appropriate stage in the production process of the cellulose ester, for example, acetylation or saponification, for example, hydrogen peroxide; peracid (eg, formic acid). , Peracetic acid, perbenzoic acid, lauroyl peroxide, benzoyl peroxide); organic peroxides such as diacetyl peroxide. The amount of the oxidizing agent to be used is 0.01 to 5 parts by mass, preferably 0.1 to 2.5 parts by mass, particularly about 0.1 to 1 part by mass with respect to 100 parts by mass of the cellulose ester. The treatment with the oxidizing agent can be performed at 20 to 100 ° C, preferably about 30 to 70 ° C. Furthermore, in order to improve the stability of the cellulose ester, a heat-resistant stabilizer such as an alkali metal salt (eg, potassium salt, sodium salt) or an alkaline earth metal salt (eg, calcium salt, magnesium) Salt, strontium salt, barium salt).

In the cellulose ester, at least a part of the carboxyl groups bonded to the cellulose ester and / or hemicellulose acetate exists in an acid form.
In some cases, the total content of alkali metals (lithium, sodium, potassium) and alkaline earth metals (calcium, magnesium) in 1 g of cellulose acetate is an effective amount or more and 5.5 × 10 ⁻⁶ equivalent (ion equivalent conversion) ) The following cellulose acetates are included. The concentration of the cellulose ester is 5 to 30% by mass based on the total amount of the cellulose ester solution.
It is 0 to 28% by mass, particularly preferably 15 to 25% by mass. The cellulose ester preferably contains water at 2% by mass or less, more preferably 1% by mass or less, and particularly preferably a cellulose ester having a water content of 0.7% by mass or less. Generally, the cellulose ester contains 2.5 to 5% by mass of water and needs to be dried. The method is not particularly limited as long as the desired water content is obtained. For example, drying may be carried out at a high temperature in a dryer, high-temperature air may be sent, or drying may be carried out at a reduced pressure and at a low temperature.

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. Alternatively, the moisture of the cellulose ester may be reduced by allowing the desiccant to absorb moisture using the desiccant to obtain a cellulose ester having the above-mentioned water content. The drying time is not particularly limited, and the drying is carried out so that the water content of the cellulose ester becomes the above. The water content of these cellulose esters can be determined by collecting a certain amount of the cellulose esters and measuring with a Karl Fischer.

In forming the cellulose ester film, the cellulose ester solution contains at least one release agent having a pka of 4 or less by 0.005 to 2% by mass of the solution. As the release agent, a compound represented by the following formula (1) or (2) is preferable. (1) (R1-B1-O) _n1- P (= O)-(OM
1) _n2 (2) R2-B2-X Here, R1 and R2 represent a substituted or unsubstituted alkyl group, alkenyl group, aralkyl group or aryl group having 4 to 40 carbon atoms, and M1 is an alkali metal, ammonia , A lower alkylamine. B1 and B2 represent a divalent linking group, and X represents a sulfonic acid (or a salt thereof) or a sulfate (or a salt thereof). n1 is 1
Or 2 and n2 represents an integer of (3-n1).
All of these acid groups have a pKa of 2 or less.

In the formula (1) or (2), R1 and R
Examples of 2 include a substituted or unsubstituted alkyl group having 4 to 40 carbon atoms (eg, butyl, hexyl, octyl, 2-ethylhexyl, nonyl, dodecyl, hexadecyl, octadecyl, eicosanyl, docosanyl, myril), 4 to 40 substituted or unsubstituted alkenyl groups (eg,
2-hexenyl, 9-decenyl, oleyl), carbon number 4
To 40 substituted or unsubstituted aryl groups (eg, phenyl, naphthyl, methylphenyl, dimethylphenyl, trimethylphenyl, ethylphenyl, propylphenyl, diisopropylphenyl, triisopropylphenyl, t-butylphenyl, di-t-butylphenyl , Tri-t-butylphenyl, isopentylphenyl, octylphenyl, isooctylphenyl, isononylphenyl, diisononylphenyl, dodecylphenyl, isopentadecylphenyl).

Preferred alkyl groups are hexyl, octyl, 2-ethylhexyl, nonyl, dodecyl, hexadecyl, octadecyl and docosanyl. A preferred alkenyl group is oleyl. Preferred aryl groups are phenyl, naphthyl, trimethylphenyl, diisopropylphenyl, triisopropylphenyl, di-t
-Butylphenyl, tri-tert-butylphenyl, isooctylphenyl, isononylphenyl, diisononylphenyl and dodecylisopentadecylphenyl. Next, the divalent linking groups B1 and B2 will be described. C1-C10 alkylene, poly (degree of polymerization 1-5
0) oxyethylene, poly (degree of polymerization 1-50) oxypropylene, poly (degree of polymerization 1-50) oxyglycerin,
And a mixture of these may be used. Preferred linking groups are methylene, ethylene, propylene, butylene, poly (degree of polymerization 1 to 25) oxyethylene, poly (degree of polymerization 1 to 25) oxypropylene, and poly (degree of polymerization 1 to 1).
5) Oxyglycerin. X is a carboxylic acid (or salt), a sulfonic acid (or a salt), or a sulfate (or a salt), and particularly preferably a sulfonic acid (or a salt) or a sulfate (or a salt). The salts are preferably Na, K, ammonium, trimethylamine and triethanolamine. Hereinafter, specific examples of the release agent will be described.

RZ-1: C₈H₁₇OP (= O)-(OH)_Two RZ-2: C₁₂H_{twenty five}OP (= O)-(OK)_Two RZ-3: C₁₂H_{twenty five}OCH_TwoCH_TwoOP (= O)-
(OK)_Two RZ-4: C₁₅H₃₁(OCH_TwoCH_Two)_FiveOP (=
O)-(OK)_Two RZ-5: ｛C₁₂H_{twenty five}O (CH_TwoCH_2O)_Five｝_Two−P
(= O) -OH RZ-6: ｛C₁₈H₃₅(OCH_TwoCH_Two)₈O｝_Two−P
(= O) -ONH_Four RZ-7: (t-C_FourH₉)_Three-C₆H_Two-OCH_TwoC
H_TwoOP (= O)-(OK)_Two RZ-8: (iso-C₉H₁₉-C₆H_Four-O- (CH
_TwoCH_TwoO)_Five-P (= O)-(OK) (OH) RZ-9: C₁₂H_{twenty five}SO_ThreeNa RZ-10: C₁₂H_{twenty five}OSO_ThreeNa RZ-11: C₁₇H₃₃COOH RZ-12: C₁₇H₃₃COOH ・ N (CH_TwoCH_TwoO
H)_Three RZ-13: iso-C₈H₁₇-C₆H_Four-O- (CH
_TwoCH_TwoO)_Three− (CH _Two)_TwoSO_ThreeNa RZ-14: (iso-C₉H₁₉)_Two-C₆H_Three-O-
(CH_TwoCH_TwoO)_Three− (CH_Two)_FourSO_ThreeNa RZ-15: triisopropylnaphthalenesulfonic acid
Sodium RZ-16: tri-t-butylnaphthalenesulfonic acid
Sodium RZ-17: C₁₇H₃₃CON (CH_Three) CH_TwoCH_TwoS
O_ThreeNa RZ-18: C₁₂H_{twenty five}-C₆H_FourSO_Three・ NH_Four The amount of the release agent of the formula (1) or (2) used is 0.0% of the solution.
02 to 2% by mass, more preferably 0.005 to 5% by mass.
1 mass%, more preferably 0.01 to 0.5 quality
%. The method of addition is not particularly limited,
Liquid or solid, with other materials before dissolving
May be added as a solution, or may be prepared in advance
It may be added to the acylate solution later.

Next, an organic acid is used as a release agent having a pKa of 4 or less.
Is mentioned. Acid dissociation index pKa 1.93-4.50
(Preferably 2.00 or more, more preferably 2.20 or less
Above, more preferably 2.50 or more, most preferably
2.60 or more, and preferably 4.40 or less, furthermore
Preferably 2.20 to 4.30 or less, most preferably
Acids of 4.00 or less) include inorganic acids and organic acids.
You. For the pKa of acids, see "Revision 3rd Edition Chemical Handbook, Basics
Edition II "(edited by The Chemical Society of Japan, published by Maruzen Co., Ltd.)
it can. In the following, along with specific examples of acids,
The index pKa is shown. These acids are disclosed in JP-A-10-316.
No. 701 discloses details. That is,
As the inorganic acid, for example, HClO_Two(2.31), H
OCN (3.48), molybdic acid (H_TwoMoO_Four,
3.62), HNO_Two(3.15), phosphoric acid (H_ThreePO
_Four, 2.15), tripolyphosphoric acid (H_FiveP_ThreeO _Ten, 2.
0), vanadic acid (H_ThreeVO_Four, 3.78).
You.

Examples of the organic acid include aliphatic monocarboxylic acids [formic acid (3.55), oxaloacetic acid (2.2)
7), cyanoacetic acid (2.47), phenylacetic acid (4.1)
0), phenoxyacetic acid (2.99), fluoroacetic acid (2.59), chloroacetic acid (2.68), bromoacetic acid (2.72), iodoacetic acid (2.98), mercaptoacetic acid (3.43) , Acetic acid having a substituent of vinyl acetic acid (4.12), chloropropionic acid (2.71-3.92)
Halopropionic acid, 4-aminobutyric acid (4.0
3), acrylic acid (4.26)], aliphatic polycarboxylic acid [malonic acid (2.65), succinic acid (4.00), glutaric acid (4.13), adipic acid (4.26) , Pimelic acid (4.31), azelaic acid (4.39), fumaric acid (2.85)], oxycarboxylic acid [glycolic acid (3.63), lactic acid (3.66), malic acid (3. 2
4), tartaric acid (2.82-2.99), citric acid (2.
87)], aldehyde acid or ketone acid [glyoxylic acid (3.18), pyruvic acid (2.26), levulinic acid (4.44)], aromatic monocarboxylic acid [anilinesulfonic acid (3.74-3) .23), benzoic acid (4.2
0), aminobenzoic acid (2.02-3.12), chlorobenzoic acid (2.92-3.99), cyanobenzoic acid (3.60-3.55), nitrobenzoic acid (2.17-
3.45), hydroxybenzoic acid (4.08-4.5).
8), anisic acid (4.09-4.48), fluorobenzoic acid (3.27-4.14), chlorobenzoic acid, bromobenzoic acid (2.85-4.00), iodobenzoic acid (2 8.6-4.00), benzoic acid, salicylic acid (2.81), and naphthoic acid (3.70-4.1).
6), cinnamic acid (3.88), mandelic acid (3.1)
9)], aromatic polycarboxylic acid [phthalic acid (2.7
5), isophthalic acid (3.50), terephthalic acid (3.
54)], heterocyclic monocarboxylic acid [nicotinic acid (2.
05), 2-furancarboxylic acid (2.97)] and a heterocyclic polycarboxylic acid [2,6-pyridinedicarboxylic acid (2.09)].

Organic acids include amino acids [ie, amino acids and amino acid derivatives (substituted amino acids,
A peptide composed of about 5 amino acids)]. The amino acids include, for example, amino acids [asparagine (2.14), aspartic acid (1.93), adenine (4.07), alanine (2.30), β-alanine (3.53), arginine (2 .05), isoleucine (2.32), glycine (2.36), glutamine (2.17), glutamic acid (2.18), serine (2.13), tyrosine (2.17), tryptophan (2. 35), threonine (2.21), norleucine (2.30), valine (2.26), phenylalanine (2.26), methionine (2.15), lysine (2.35).
04), leucine (2.35)], amino acid derivative [adenosine (3.50), adenosine triphosphate (4.0)
6), adenosine phosphate (3.65-3.80), L-
Alanyl-L-alanine (3.20), L-alanylglycine (3.10), β-alanylglycine (3.1
8), L-alanylglycylglycine (3.24), β
-Alanylglycylglycine (3.19), L-alanylglycylglycylglycine (3.18), glycyl-
L-alanine (3.07), glycyl-β-alanine (3.91), glycylglycyl-L-alanine (3.
18), glycylglycylglycine (3.20), glycylglycylglycylglycine (3.18), glycylglycyl-L-histidine (2.72), glycylglycylglycyl-L-histidine (2.90) Glycyl-DL-histidylglycine (3.26), glycyl-
L-histidine (2.54), glycyl-L-leucine (3.09), γ-L-glutamyl-L-cysteinylglycine (2.03), N-methylglycine (sarcosine, 2.20), N, N-dimethylglycine (2.0
8), citrulline (2.43), 3,4-dihydroxyphenylalanine (2.31), L-histidylglycine (2.84), L-phenylalanylglycine (3.
02), L-prolylglycine (3.07), L-leucyl-L-tyrosine (3.15) ".

As the acid, organic acids such as aliphatic monocarboxylic acids [formic acid, haloacetic acid of chloroacetic acid, halopropionic acid, saturated or unsaturated C1-3 monocarboxylic acid of acrylic acid] and aliphatic polycarboxylic acids are usually used. Polycarboxylic acids [saturated or unsaturated C2-4 of malonic acid, succinic acid, glutaric acid, fumaric acid]
A dicarboxylic acid], an oxycarboxylic acid [glycolic acid, lactic acid, malic acid, tartaric acid, a C1-6 oxycarboxylic acid of citric acid], an amino acid or a derivative thereof are often used. These acids may be water-insoluble or water-soluble. The acid may be used as a free acid or as an alkali metal salt or an alkaline earth metal salt. Examples of the alkali metal include lithium, potassium, and sodium, and examples of the alkaline earth metal include calcium, magnesium, barium, and strontium. Preferred alkali metals include sodium, and preferred alkaline earth metals include calcium and magnesium. These alkali metals and alkaline earth metals can be used alone or in combination of two or more, and the alkali metal and the alkaline earth metal may be used in combination. The total content of the acid and its metal salt is from 0.002 to
2 mass%, more preferably 0.005 to 1 mass%
And more preferably 0.01 to 0.5% by mass.

The cellulose ester solution having an acid having an acid dissociation index pKa of 4.5 or less or a metal salt thereof is as follows:
Finally, the acid or its metal salt may be present in the cellulose ester solution before the casting, and the addition position may be at any stage and is not particularly limited. They can be carried out in any step, for example, a step of producing a cellulose ester (for example, a step of adding a heat stabilizer after completion of the hydrolysis / ripening step) or after the production of the cellulose ester. The treatment with an acid or a metal salt thereof may be performed by washing, dipping, or impregnating powdery or flaky cellulose acetate. Further, the mixing or treatment may be performed by adding an acid or a metal salt thereof to a dope containing a cellulose ester. Here, the mixing or treatment of the acid having the acid dissociation index pKa or the metal salt thereof is performed at an appropriate temperature which does not impair the workability, for example, -10 to 50 ° C (preferably 0 to 5 ° C).
0 ° C.), and the mixing or treatment time is
It can be selected from an appropriate range, for example, a range of about 1 minute to 12 hours. When such an acid having a specific pKa or a metal salt thereof is used, at least a part of the carboxyl groups bonded to cellulose acetate and / or hemicellulose acetate can be present as an acid-type carboxyl group, which can be used for casting or film. It becomes a factor excellent in surface condition.

The non-chlorine type organic solvent comprises methyl acetate, ketone having 3 to 6 carbon atoms and alcohol having 1 to 4 carbon atoms. Acetone as a ketone having 3 to 6 carbon atoms,
Examples include methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone and diacetone alcohol, and methyl acetoacetate. Acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone and cyclopentanone are preferred, and acetone, methyl ethyl ketone and cyclopentanone are particularly preferred. The alcohol having 1 to 4 carbon atoms is preferably methanol, ethanol, propanol, or butanol, and particularly preferably methanol, ethanol, or butanol. In addition, as the alcohol, a fluorinated alcohol is also used. For example, 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,
3,3-tetrafluoro-1-propanol is also included. These ketone solvents and alcohols may be used alone or as a mixture of two or more, and are not particularly limited.

In the above mixed solvent, methyl acetate is 20 to 9
0% by mass, preferably 5 to 60% by mass of ketone solvent and 5 to 30% by mass of alcohol,
Further, 30-86% by mass of methyl acetate and 7% of ketone solvent
-50% by mass, preferably 7-25% by mass of alcohol, particularly 30-80% by mass of methyl acetate, 10-50% by mass of ketone solvent, 10-20% of alcohol
It is preferably contained by mass%. Specific examples of preferred combinations of these solvents include the following. Cellulose ester / methyl acetate / methyl ethyl ketone / acetone / methanol / ethanol (X /
(50-X) / 20/20/5/5, parts by mass), cellulose ester / methyl acetate / acetone / methyl acetoacetate / ethanol (X / (75-X) / 20/10 //
5, parts by mass), cellulose ester / methyl acetate / cyclopentanone / methanol / ethanol (X / (80-
X) / 10/5/5, parts by mass), cellulose ester /
Methyl acetate / acetone / methanol / ethanol (X /
(80-X) / 20/5/5, parts by mass), cellulose ester / methyl acetate / methyl ethyl ketone / acetone /
Methanol / ethanol / butanol (X / (80-
X) / 10/5/5/5/5, parts by mass) is a preferable combination. Here, X represents a part by mass of the cellulose ester, preferably 5 to 25, and particularly preferably 10 to 25.

More specific preferred ratios of the solvents are described below. Specific examples of preferred combinations of these solvents include the following. Methyl acetate / acetone / methanol / ethanol / butanol (75/10/5/5/5, parts by mass), methyl acetate /
Acetone / methanol / ethanol / propanol (7
5/10/5/5/5/5, parts by mass), methyl acetate / acetone / methanol / ethanol / cyclohexane (75 /
10/5/5/5, parts by mass), methyl acetate / methyl ethyl ketone / methanol / ethanol (80/10/5 /
5, mass parts), methyl acetate / acetone / methyl ethyl ketone / ethanol (75/10/5/5, mass parts),
Methyl acetate / cyclopentanone / methanol / ethanol (80/10/5/5, parts by mass), methyl acetate / cyclopentanone / methanol / ethanol (80/10/5
5/5, parts by mass), methyl acetate / cyclopentanone / acetone / methanol / ethanol (60/15/15 /
5/5, parts by mass), methyl acetate / cyclohexanone / methanol / hexane (70/20/5/5, parts by mass),
Methyl acetate / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20/5/5, parts by mass), methyl acetate / 1,3 dioxolane / methanol /
Ethanol (70/20/5/5, parts by mass), methyl acetate / dioxane / acetone / methanol / ethanol (60/20/10/5/5, parts by mass), methyl acetate /
Acetone / cyclopentanone / ethanol / butanol / cyclohexane (65/10/10/5/5/5, parts by mass), methyl formate / methyl ethyl ketone / acetone /
Methanol / ethanol (50/20/20/5/5,
Parts by mass), methyl formate / acetone / ethyl acetate / ethanol / butanol / hexane (65/10/10/5 /
5/5, parts by mass), acetone / methyl acetoacetate / methanol / ethanol (65/20/10/5, parts by mass), acetone / cyclopentanone / ethanol / butanol (65/20/10/5, parts by mass) ),acetone/
1,3 dioxolane / ethanol / butanol (65 /
20/10/5, parts by mass), 1,3 dioxolane / cyclohexanone / methyl ethyl ketone / methanol / butanol (55/20/10/5/5/5, parts by mass), acetone / methylene chloride / methanol (85/5 / parts by mass) 5, mass parts), methyl acetate / methylene chloride / methanol / ethanol (70/10/15/5, mass parts), 1,3-dioxolan / methylene chloride / methanol / butanol (70/15/10/5, mass Parts), 1,4-dioxane / methylene chloride / acetone / methanol / butanol (70/5/15/5/5, parts by mass), cyclohexanone / methylene chloride / acetone / methanol / ethanol / propanol (60/10/15 / 5/5/5, parts by mass), which is a preferable combination.
The dope may contain methylene chloride in an amount of 10% by mass or less based on the total amount of the organic solvent, in addition to the above organic solvent.

In dissolving the cellulose ester,
The cellulose ester in a solvent at room temperature beforehand.
Preferably. That is, the cellulose ester
The powder with good stirring, or vice versa.
Then, the solvent is added to the cellulose ester,
A swelling solution of the cellulose ester can be prepared. What
Note that the solvent may be a mixed solvent, and any one of them may be used.
May be added separately, and there is no particular limitation. Al
Aggregate cellulose ester by adding coal first
May be easily dissolved without causing
It is. The preferred time for swelling is preferably 0.1 to 24 hours
And more preferably from 0.2 to 6 hours, and more preferably from 0.2 to 6 hours.
5 to 3 hours. The mixture of cellulose ester and solvent
Strong stirrers are preferred because viscosity increases significantly
If necessary, use a kneader or screw extruder
Or the like. For example, a place of stirring
In this case, the peripheral speed of the stirring blade is preferably 0.01 to 2 m / sec.
And more preferably 0.05 to 1.5 m / sec.
05 to 1 m / sec. In addition, the cellulose S
The shearing force of tell is 1-100,000 kgf / sec. ^Two Is preferred
And furthermore, 100,000 kgf / sec ^Two Is preferred.

In the cooling dissolution method, the swollen cellulose ester solution is kept at -100 to -10 ° C, preferably at -80 ° C.
It is cooled to -10C, more preferably -80C to -30C, most preferably -80C to -50C. The cooling can be performed, for example, with a mechanical refrigerator (-100 ° C), a dry ice / methanol bath (-75 ° C) or a cooled diethylene glycol solution (-30 to -20 ° C). Upon such cooling, the mixture of the cellulose ester 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 ester solution increases with cooling, and the cooling efficiency is inferior. is necessary. Also, after swelling the cellulose ester solution,
This 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,
Shorter is preferable in terms of productivity, and the time is 0.5 to 18
0 minutes is preferable, more preferably 0.5 to 30 minutes, and particularly preferably 0.5 to 10 minutes. It is preferable that the cellulose ester solution obtained by cooling is then heated to 0 to 50 ° C., whereby a solution in which the cellulose ester flows in an organic solvent is obtained.

Further, the mixed solution of the cellulose ester and the organic solvent is 70 to 200 MPa under a pressure of 0.3 to 30 MPa.
It can also be prepared by a method of dissolving by heating to ° 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, more preferably from 0.5 to 30 minutes, particularly preferably from 1 to 30 minutes.
10 minutes. The heating method is not particularly limited. For example, high-pressure steam or an electric heat source may be used. Furthermore, a so-called supercritical state dissolving method may be adopted in which carbon dioxide gas is allowed to coexist in the solvent, and carbon dioxide is preferably 5 to 30% by mass in the solution. In this case, dissolution can be achieved at a lower temperature and a higher pressure. For high pressure, a pressure vessel or pressure line is required, but any of iron or stainless steel or other metal pressure vessel or line may be used, and there is no particular limitation.

Next, since the heated solution cannot be handled as it is, it is necessary to cool it to a temperature lower than the lowest boiling point of the solvent used. In that case, it is common to cool to −10 to 50 ° C. and return to normal pressure. For cooling, the high-pressure high-temperature vessel or line containing the cellulose ester solution may be simply left at room temperature, and more preferably the apparatus may be cooled using a coolant of 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 the pressure or reducing the pressure. In order to perform pressurization and decompression, a pressure-resistant container or line is essential. The cellulose ester solution can be prepared by the above-mentioned cooling and high-temperature and high-pressure, but the order is not particularly limited. However, in order to filter and cast the produced cellulose ester solution, it is preferable to carry out the filtration at room temperature, and it is more preferable to dissolve the solution at a high temperature and a high pressure after cooling. The cooling dissolution method and the high-temperature high-pressure dissolution method described above may be performed alone, or both may be performed.

The solution obtained above is characterized by a high concentration, and a cellulose ester solution having a high concentration and excellent stability can be obtained without resorting to the means of concentration. 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. A method of obtaining a high-concentration solution while evaporating the solvent by giving a difference (described in Japanese Patent Application Laid-Open No. 4-259511). While flash evaporating the solvent, the solvent vapor is extracted from the container,
A method of extracting a highly concentrated solution from the bottom of a container (US Pat. No. 254)
Nos. 1012, 2858229, 4414341
No. 4,504,355).

Various additives can be added to the cellulose ester solution in each preparation step according to the use. 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 are plasticizers, UV inhibitors and deterioration inhibitors (eg, antioxidants, peroxide decomposers, radical inhibitors, metal deactivators, acid scavengers, amines). Phosphoric acid esters or carboxylic acid esters are preferably used as the plasticizer. Examples of phosphate esters include triphenyl phosphate (TPP) and tricresyl phosphate (TCP). The carboxylic acid esters include phthalic acid esters and citrate esters, and dibutyl phthalate (DBP),
Includes dioctyl phthalate (DOP) and diethylhexyl phthalate (DEHP). Examples of citrate esters include O-acetyl triethyl citrate (OAC
TE) and tributyl O-acetylcitrate (OAC
TB), acetyltriethyl citrate, acetyltributyl citrate. These plasticizers may be used alone or in combination of two or more. The amount of the plasticizer added is 5 to 30% by mass or less, especially 8 to
It is preferably at most 16% by mass. These compounds may be added together with the cellulose ester and the solvent when preparing the cellulose ester solution, or may be added during or after the solution is prepared. Other examples of plasticizers for reducing optical anisotropy include (di) pentaerythritol esters described in JP-A-11-124445,
Glycerol esters described in 246704,
Diglycerol esters described in JP-A-2000-63560, citrates 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 ray inhibitor, JP-A-60-235852 and JP-A-3-199201.
No., 5-1907073, 5-194789,
5-271471, 6-107854, 6-
Nos. 118233, 6-148430, 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 added is preferably 0.01 to 1% by mass of the prepared cellulose ester 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). More preferably, the cellulose ester solution contains one or more UV absorbers. The UV absorber for liquid crystal is excellent in the ability to absorb ultraviolet light having a wavelength of 370 nm or less from the viewpoint of preventing deterioration of the liquid crystal, and has a wavelength of 400 from the viewpoint of liquid crystal display.
Those having a small absorption of visible light of nm or more are preferable. Examples include oxybenzophenone-based compounds, benzotriazole-based compounds, salicylic acid ester-based compounds, benzophenone-based compounds, cyanoacrylate-based compounds, and nickel complex salt-based compounds. Particularly preferred ultraviolet absorbers are benzotriazole-based compounds and benzophenone-based compounds. Among them, benzotriazole compounds are
This is preferable because unnecessary coloring of the cellulose ester is small.

The amount of these compounds to be added is preferably 0.001 to 5.0% by mass, more preferably 0.002 to 3% by mass, based on the cellulose ester. A retardation increasing agent for controlling optical anisotropy is optionally added to the cellulose ester solution. In order to adjust the retardation of the cellulose ester film, it is preferable to use an aromatic compound having at least two aromatic rings as a retardation increasing agent. The optical characteristics will be described. The in-plane retardation (Re) of the film is 0 to 300 nm
It is used according to the use within the range. Further, the retardation (Rth) in the thickness direction of the film is also important, and the Rth of the cellulose ester film is 0 n / 100 μm.
m to 600 nm, and more preferably 0 to 400 nm.

Further, as a support for a light-sensitive material, a colorant compound for preventing light piping may be added. Fine particles (matting agent) for improving the slipperiness (preventing creaking) of cellulose ester film and the adhesion resistance under high humidity
It is preferred to use Cellulose ester film has an average height of protrusions on its surface of 0.005 to 10
μm, preferably 0.01 to 5 μm, and when forming projections with a spherical or irregular matting agent, the content is 0.5 to 600 mg / m ² , more preferably 1 to 400 mg. / M ² . At this time, the matting agent used is not particularly limited in its composition, and may be an inorganic or organic material, or a mixture of two or more types. The matting agent is preferably an inorganic fine powder of silica, kaolin, talc, diatomaceous earth, quartz, calcium carbonate, barium sulfate, titanium oxide, alumina, manganese colloid, titanium dioxide, strontium barium sulfate, silicon dioxide. Alkaline earth metals (eg, calcium,
Heat stabilizers such as salts of magnesium) are also preferred.

Prior to casting, the solution is preferably filtered to remove foreign substances such as undissolved matter, dust, and impurities using a suitable filtering material such as a wire mesh, paper, or flannel. Absolute filtration accuracy is 0.05-100μ for filtration of cellulose ester solution
m is used, and the absolute filtration accuracy is set to 0.
It is preferable to use a filter having a size of 5 to 10 μm.
In that case, it is 16 kg / cm ² or less (preferably 12 kg / cm ^2).
/ Cm ² or less, more preferably 10 kg / cm ² or less,
It is particularly preferable to filter at a filtration pressure of ² kg / cm ² or less.

A method for producing a film using a cellulose ester solution will be described. As a method and equipment for producing a cellulose ester film, a solution casting film forming method and a solution casting film forming apparatus conventionally used for producing a cellulose ester film are used. The dope (cellulose ester solution) prepared from the dissolution tank (tank) is temporarily stored in a stock tank, and the foam contained in the dope is 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. Clip the ends of the resulting web with clips,
While maintaining the width, the sheet is conveyed by a tenter and dried. Subsequently, the sheet is conveyed 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 a solution casting film forming apparatus, an undercoat layer, an antistatic layer, an antihalation layer, a protective layer, etc. In order to process the surface of the support, a coating device is often added.

The obtained cellulose ester solution may be cast as a single layer solution on a smooth band or a drum as a support, or a so-called “two or more layers of cellulose ester solution” may be cast. They may be co-cast. When casting a plurality of cellulose ester solutions, a film may be produced while casting and laminating a solution containing cellulose ester from a plurality of casting ports provided at intervals in the traveling direction of the support, respectively. For example, JP-A-61-1584
No. 14, JP-A-1-122419 and JP-A-11-124
The method described in each publication of 198285 can be applied. Alternatively, the film may be formed by casting a cellulose ester solution from two casting ports,
For example, JP-B-60-27562, JP-A-61-947.
No. 24, JP-A-61-947245, JP-A-61-1
No. 04813, JP-A-61-158413 and JP-A-6-134933. A cellulose ester film casting method described in JP-A-56-162617, in which a flow of a high-viscosity cellulose ester solution is wrapped with a low-viscosity cellulose ester solution and the high- and low-viscosity cellulose ester solutions are simultaneously extruded. Good.

Alternatively, 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.
This is a method described in JP-A-4-220235. 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. Also,
It is preferable to add a functional material to the outermost layer. For example, it is preferable to add a release agent or a matting agent, whereby a desired film can be produced without changing the characteristics of the film. Furthermore, the cellulose ester solution can be simultaneously cast with other functional layers (eg, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, a UV absorbing layer, and a polarizing layer).

Drying of the dope on the support in the production of the cellulose ester film is generally carried out by a method in which hot air is blown from the surface side of the support (drum or belt), that is, from the surface of the web on the support. Alternatively, a hot air is applied from the back of the belt, and a liquid whose temperature is controlled is brought into contact with the back of the belt or drum opposite the dope casting surface, and the drum or belt is heated by heat transfer to control the surface temperature. Although there are methods and the like, the 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 ester film is 30 to 250 ° C, especially 40 ° C.
To 180 ° C. is preferred, as described in JP-B-5-17844.

Further, there is a method of positively stretching in the width direction. For example, JP-A-62-115035,
-152125, 4-284221, 4-29
Nos. 8310 and 11-48271. In order to increase the in-plane retardation value of the cellulose ester 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. The stretching ratio of the film (ratio of increase by stretching to the original length) is preferably 10 to 30%.

The thickness of the finished (after drying) cellulose ester film varies depending on the purpose of use, but is usually in the range of 5 to 500 μm, preferably in the range of 20 to 250 μm, particularly preferably in the range of 30 to 180 μm. . 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 ester film, the adhesion between the cellulose ester film and each functional layer (eg, undercoat layer, back layer) can be improved. Glow discharge treatment, ultraviolet irradiation treatment, corona treatment, flame treatment, acid or alkali treatment can be used. Here, the glow discharge treatment is 10 ⁻³ to
This is so-called low-temperature plasma generated under a low-pressure gas of 20 Torr. Further, an alkali saponification treatment preferably used as a surface treatment of a cellulose ester film will be specifically described. After immersing the cellulose ester film surface in an alkaline solution, it is preferably neutralized with an acidic solution, washed with water and dried. Examples of the alkaline solution include a potassium hydroxide solution and a sodium hydroxide solution.
It is preferably 3.0 N, and more preferably 0.5 N to 2.0 N. The temperature of the alkali solution is preferably in the range of room temperature to 90 ° C, more preferably 40 ° C to 70 ° C. Next, the cellulose ester 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 ester film. At this time, the acid is hydrochloric acid,
Examples thereof include nitric acid, sulfuric acid, acetic acid, formic acid, chloroacetic acid, and oxalic acid, and the concentration thereof is preferably 0.01 N to 3.0 N, and more preferably 0.05 N to 2.0 N. When the cellulose ester film is used as a transparent protective film of a polarizing plate, from the viewpoint of adhesiveness with the polarizing film,
It is particularly preferable to carry out an acid treatment or an alkali treatment, that is, a saponification treatment for cellulose acetate.

In order to achieve adhesion between the cellulose ester film support and the functional layer, a surface activation treatment is performed, and then the functional layer is directly applied on the cellulose ester film to obtain an adhesive force. It is also preferable to provide an undercoat layer (adhesive layer) after or after the surface treatment, and apply a functional layer thereon.

In the construction of the protective film for the polarizing plate,
At least one antistatic layer
Hydrophilic binder layer for providing and bonding to polarizer
Is preferably provided. As a conductive material,
Conductive metal oxides and conductive polymers are preferred. In addition, steam
A transparent conductive film formed by deposition or sputtering may be used. Conductive
The conductive layer may be the outermost layer or the inner layer without any problem. Guidance
The power transmission of the electric layer has a resistance of 10E0 to 10E12Ω.
It is preferable that it is particularly 10E0 to 10E10Ω.
Is preferred. Metal oxides are preferred, for example Z
nO, TiO _Two , SnO _Two , Al _Two O _Three , In _Two O _Three ,
SiO _Two , MgO, BaO, MoO _Two , V _Two O _Five Etc.
Or these composite oxides are preferable, and in particular, ZnO, Sn
O _Two Or V _Two O _Five Is preferred. These conductive metals
The compound may be crystalline or amorphous, and the morphology is spherical
However, it may be needle-like, scale-like or sol-like, and is not particularly limited.
No. When the primary particle diameter is not less than 100 ° and not more than 0.2 μm,
The major axis of the higher order structure of these aggregates is 300 mm or more and 6 μm or less
Powder with a specific structure is added to the conductive layer by volume fraction
Preferably, it is contained in an amount of 0.01% or more and 20% or less.
The volume resistivity of these conductive metal compounds is 10
E-6Ωcm to 10E5Ωcm, especially preferred
The volume resistivity is 10E-6Ω · cm to 10E2Ω ·
cm.

Examples of the conductive ionic polymer compound include anionic polymer compounds as disclosed in JP-B-49-23828, JP-B-49-23827 and JP-B-47-28937; No., JP 50
No. 54672, JP-B-59-14735, 57-
Nos. 18175, 57-18176 and 57-5
Ionene-type polymers having a dissociating group in the main chain, such as those disclosed in JP-A-6059 / JP-A-6059;
No. 23, No. 57-15376, JP-B-53-4523
No. 1, No. 55-145783, No. 55-65950
Nos. 55-67746, 57-11342, 57-19735, JP-B-58-56858, JP-A-61-27853 and JP-A-62-9346. Cationic pendant polymers having a cationic dissociating group in the chain; Further, as the conductive material, an organic electron conductive material is preferable, and examples thereof include a polyaniline derivative, a polythiophene derivative, a polypyrrole derivative, and a polyacetylene derivative.

A surfactant is preferably used in any of the functional layers, and any of nonionic, cationic and betaine types can be used. Further, those fluorine-based surfactants are also preferably used as a coating agent in an organic solvent or as an antistatic agent. Further, it is preferable to include a slipping agent in any one of the layers above the cellulose ester film.
75 and 146, higher fatty acid amides disclosed in JP-B-58-33541 and British Patent Nos. 927 and 446, or JP-A-55-12.
No. 6,238, No. 58-90633, and higher fatty acid esters (having 10 to 24 carbon atoms).
Of fatty acids and alcohols having 10 to 24 carbon atoms)
Etc. are known.

Cellulose comprising a cellulose ester solution
Sester film can be used in various applications
You. Cellulose ester film is used to
It is particularly effective when used as a scientific compensation sheet. Cellulo
Optical compensation for the film itself
It can be used as a sheet. In addition, the film
When using as an optical compensation sheet, a polarizing element
(Described later) and the cellulose ester film
Substantially parallel or perpendicular to the slow axis of the optical compensatory sheet
It is preferable to arrange them so as to be straight. Such a bias
The arrangement of the optical element and the optical compensation sheet is described in
No. 0-48420. The liquid crystal display device
A liquid crystal cell that holds liquid crystal between two electrode substrates,
Polarizing elements disposed on both sides of the liquid crystal cell, and the liquid crystal cell
And at least one optical compensatory sheet between the polarizing element
Are arranged. The liquid crystal layer of the liquid crystal cell
Usually, a spacer is formed between two substrates.
The liquid crystal is sealed in the space. The transparent electrode layer is conductive
It is formed on a substrate as a transparent film containing a conductive substance. LCD
Gas barrier layer, hard coat layer or
Has an undercoat layer (used for bonding the transparent electrode layer)
You may ask. These layers are usually provided on a substrate
You. The substrate of the liquid crystal cell is generally 80 to 500 μm thick.
Having.

The optical compensation sheet is a birefringent film for removing coloring of the liquid crystal screen. The cellulose ester 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 ester film. Further, in order to improve the viewing angle of the liquid crystal display device, a cellulose ester film and a film exhibiting the opposite birefringence (positive / negative relationship) may be used as an optical compensatory sheet. The range of the thickness of the optical compensation sheet is
This is the same as the preferred thickness of the film 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 preferably has a thickness of 25 to 350 μm, more preferably 30 to 200 μm. 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. As described above, 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 been proposed (JP-A-3-9325).
And JP-A-6-148429, JP-A-8-50206 and JP-A-9-26572). A cellulose ester film can also be used as a support for such an optical compensation sheet. The cellulose ester 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 device having a HAN mode liquid crystal cell. Of an optical compensatory sheet, ASM (Axially Symmetric Aligned Microc)
ell) It is preferably used as a support of an optical compensation sheet of an ASM type liquid crystal display device having a liquid crystal cell of a mode.

[0053]

EXAMPLES In each example, the characteristics were evaluated as follows. (1) Vertical Streaks of Film (abbreviated as streak) The obtained film was visually observed, and the defects of the vertical streaks were 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 found on the film surface. B: Slight bumps were observed on the film surface. C: Significant bumps were observed on the film surface. D: Irregularities were observed on the film surface, and a lot of bumps 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 ester film is sandwiched between two polarizers placed in a crossed Nicols (orthogonal), and light is irradiated from one side. And observe from the other. 3m observed at this time
White spots of 5 μm or more per m2 were evaluated as follows (transmission microscope 100 times). A: There were no more than 20 white spots. B: 20 to 50 blank spots were observed. C: 50 to 100 white spots were observed. D: 100 or more white spots were observed. (5) Haze of film: Measured using a haze meter (1001DP type, manufactured by Nippon Denshoku Industries Co., Ltd.).

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 dissolving 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.

組成 Cellulose acetate solution composition─────── ───────────────────────────── Cellulose triacetate A 20 parts by mass Methyl acetate 40 parts by mass Ethyl acetate 3 parts by mass Cyclopentanone 3 parts by mass Part Acetone 12 parts by weight Methanol 5 parts by weight Ethanol 5 parts by weight C ₁₂ H ₂₅ OCH ₂ CH ₂ O-P (= O)-(OK) ₂ (release agent) 0.05 parts by weight Dipentaerythritol hexaacetate (plasticizer) A) 6 parts by mass Triphenyl phosphate (plasticizer B) 6 parts by mass Silica fine particles having a particle size of 20 nm 0.3 part by mass 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5) -Di-tert-butylanilino) -1, 0.2 parts by mass of 2,5-triazine (UV agent a) 0.2 parts by mass of 2 (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole (UV agent b) Part 2 (2′-hydroxy-3 ′, 5′-di-tert-amylphenyl) -5-chlorobenzotriazole (UV agent c) 0.2 part by mass ────────────────────────

Here, cellulose triacetate A was prepared according to JP-A-10-130301. α-
The content of cellulose was 94%, the content of mannose contained in the neutral constituent sugar was 1.4 mol%, the content of xylose was 1.52 mol%, and the mannose / xylose molar ratio was 0.92. And the total content was 3 mol% (referred to as cellulose triacetate A). The cellulose triacetate A had an acetylation degree of 59.7%, a viscosity average degree of polymerization of 320, a water content of 0.6% by mass, and a viscosity of 6% by mass in a methylene chloride solution of 320 mPa · s.

(1-2) Preparation of Cellulose Triacetate Film Solution (Dissolution by Cooling) The cellulose triacetate solution of (1-1) is fed by a screw pump and passed through a cooling part at -70 ° C. for 3 minutes. I let it. -80 ° C cooled with a refrigerator
Was carried out using the following refrigerant. 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 (manufactured by Toyo Roshi Kaisha Ltd., # 63) 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 filtered with absolute filtration accuracy of 0.01 mm (Toyo Roshi Kaisha, Ltd.)
(# 63).

(1-4) Preparation of Cellulose Triacetate Film Solution (Cooling Dissolution / High Temperature High Pressure Dissolution) The cellulose triacetate solution obtained in (1-1) is cooled and dissolved according to (1-2) and filtered. Subsequently, the high-temperature and high-pressure melting of (1-3) was performed. After cooling to 50 ° C., a filter paper having an absolute filtration accuracy of 0.01 mm (manufactured by Toyo Roshi Kaisha, Ltd.
# 63).

(1-5) Preparation of Cellulose Triacetate Film Obtained from the cellulose triacetate mixed solution of (1-1) using the dissolving method of (1-2), (1-3) or (1-4) Bring the cellulose triacetate solution to 50 ° C,
It was cast on a mirror-finished stainless steel support through a casting gieser. 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.
It dried at 30 degreeC for 30 minutes, and the samples 11, 12, and 13 of a cellulose triacetate film (80 micrometers in film thickness) were obtained.

(1-6) Results As shown in Table 1, the film produced using cellulose triacetate having a water content within the specified range was as follows:
They satisfied all of Sujira, Buttsu and Haze. On the other hand, in Comparative Samples 14 to 17 produced using the comparative cellulose triacetate exceeding the specified range, the streaks and spots were deteriorated and the haze was high. From the above, it is clear that cellulose triacetate having a molar ratio of mannose to xylose of cellulose triacetate is excellent in terms of streaks, spots and haze.

[0065]

[Table 1]

The cellulose triacetate a used in the comparative example had a cellulose content of 98%, a mannose content of 0.28 mol% in the neutral structural sugar, and a xylose content of 1.05 mol%. Comparative Films 14 to 16 were prepared and evaluated in exactly the same manner as in Sample 11, except for using. The cellulose triacetate b used in the comparative example had a cellulose content of 92.
%, Mannose content in the neutral sugar structure 3.2
A film sample 17 was prepared and evaluated in exactly the same manner as sample 11, except that a comparative cellulose triacetate having a mol% and a xylose content of 2.5 mol% was used. The cellulose triacetate a had an acetylation degree of 59.7%, a viscosity average degree of polymerization of 310, a water content of 0.5% by mass, and a viscosity of 6% by mass in a methylene chloride solution of 310 mPa · s. Cellulose triacetate b had an acetylation degree of 59.
7%, viscosity average degree of polymerization 305, water content 0.6 mass%, viscosity of 6 mass% in methylene chloride solution 320 mPa
-It was s.

[Example 2] In the sample 11, the method of Example 1 was used.
(1-1) Sample 2-2 was obtained in exactly the same manner as in Example 1 except that the cellulose acetate solution was changed from 43 parts by mass of methyl acetate to 38 parts of methyl acetate and 10 parts of acetone. The obtained sample 2-2 was A for both the uneven streaks and the spots, and the white spots were also excellent for A.

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. In the obtained sample 3-2, both the uneven streaks and 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 5 parts by mass of methanol in the (1-1) cellulose triacetate solution of Example 1 was changed to 5 parts by mass of butanol. 4-1 was obtained. The obtained sample 4-1 was excellent in A for both uneven streaks and spots, and excellent in white spots.

Example 5 Sample 1-3 was prepared in exactly the same manner as in Example 1 except that the preparation of (1-1) cellulose triacetate solution (high-temperature high-pressure dissolution) of Example 1 was changed as follows. 5-3 was obtained. In the obtained sample 5-3, A was good for both the uneven streaks and buttocks, and the white spots were excellent for A. 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 triacetate solution containing carbon dioxide was fed by a screw pump, passed through a heating part heated and pressurized to 100 ° C. and 3 MPa for 3 minutes, and then cooled to 50 ° C., and an absolute filtration accuracy of 0.01 mm Filter paper (Toyo Roshi Kaisha Co., Ltd., # 6
Filtered in 3).

Example 6 Example 1 was repeated except that the plasticizers A and B were removed as 0 parts by mass in the sample 1-3 of Example 1. Sample 6-3 was produced in the same manner as in 1. 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 cutting resistance test was performed,
Sample No. 3-3 was 105 times, whereas Sample 6-3, which was within the specified range but did not contain a plasticizer, had a cut-resistance test of 84 times, indicating no problem in practical use, but was slightly inferior. Therefore, it is clear that it is a more preferable embodiment that the cellulose triacetate film contains a plasticizer.

Example 7 A sample 7-2 was prepared in exactly 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. 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 carried out on a xenon lamp at 30,000 lux for one month,
Sample 1-2 is a haze (1001 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 1-2 was less than that of sample 1-2. 0.2
% And that of Sample 7-2 was 0.2%). Therefore,
It is clear that it is a more preferred embodiment that the cellulose triacetate film contains a UV agent.

Example 8 A sample 8-2 was prepared 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 streaks, spots, and white spots, and had an excellent haze of 0.1. On the other hand, when the two films were stacked on each other and the slipperiness was examined, it was found that Sample 1-2 could move the two films smoothly, but in the specified range, Sample 8-2 showed that the movements between the films were small. It was slightly bad. Therefore, it is clear that a more preferable embodiment is that the cellulose triacetate film contains fine particles.

Example 9 For sample 1-2, RZ-3 (C ₁₂ H ₂₅ OCH ₂ CH ₂ O—P (＝ O) — was further added to the (1-1) cellulose triacetate solution of Example 1.
Sample 9-2 was obtained in exactly the same manner as in Example 1 except that 0 parts by mass of (OK) ₂ ) was added. The obtained sample 9-2 is
Both the streaks, buttocks and margins are A and the haze is also 0.
2 was excellent. In addition, the load at the time of peeling off the sample 9-2 was slightly higher than that of the sample 1-2 (approximately 1.2 times as much load) and was inferior, but was not a problem in practical use. From the above, it is clear that the cellulose triacetate film cast by adding the release agent is excellent in releasing from the support.

[Example 10] For sample 1-3, WA-1 (C ₈ F ₁₇ CH ₂ CH ₂ O (CH ₂ CH) was added to (1-1) cellulose triacetate solution of Example 1
Example 1 except that 0.05 parts by mass of ₂ O) ₁₆ H) was added.
Sample 10-3 was obtained in exactly the same manner as described above. Obtained sample 1
In Nos. 0-3, the streaks, spots, and margins were all A, and the haze was 0.2, which was excellent. Sample 10
-3 hardly adhered to the tobacco ash. On the other hand, in sample 1-3, tobacco ash was attached. From the above, it is apparent that the cellulose triacetate film cast by adding the fluorine-based surfactant is excellent in dusting.

Example 11 Sample 11 was prepared in the same manner as in Example 1 except that the preparation of (1-2) cellulose triacetate film in Example 1 was changed as follows. -2 cellulose triacetate film was prepared. That is, a part of the cellulose triacetate solution obtained in (1-1) was sampled, and a cellulose triacetate solution (solution A) was prepared by adding 10% by mass of methyl acetate to dilute the solution. According to the co-casting method described in JP-A-06-134993, the obtained solution was laminated and co-cast with the cellulose triacetate solution of Sample 1-2 and on both sides thereof. Thus, a co-cast cellulose triacetate film was obtained. The film thickness is 3 μm on both sides.
m, the inside was 34 μm, and the total thickness was 40 μm. The surface condition of the obtained sample 11-2 was smoother than that of the sample 1-2 and had no unevenness, and the streaks, spots, and white spots were A, which was excellent. Therefore, it is clear that co-casting is a more excellent embodiment.

Example 12 For sample 1-2, 48 parts by mass of methyl acetate in the (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-halogenated organic solvent is excellent.

[Embodiment 13] JP-A-11-316378
In Example 1, the thickness of the cellulose triacetate film (second film) obtained from Sample 1-2 of Example 1 was changed to 100 μm.
Except for changing to that described in
[Example 1] described in 1-36-1378 was carried out. The obtained elliptically polarizing plate had excellent optical characteristics. Therefore, it is clear that by using a specific washing solution in the production process, a cellulose triacetate film produced thereafter is a preferable embodiment without any problem even if it is applied to an optical polarizing plate.

[Example 14] The cellulose triester film of Sample 1-2 of Example 1 was added to JP-A-7-3334.
No. 33, Fuji Photo Film Co., Ltd. of Example 1
Japanese Patent Laid-Open Publication No.
An optical compensating filter film sample was produced in exactly the same manner as in Example 1 described in JP-A-333433. 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 is excellent for optical use.

[Example 15] As a representative of various kinds of optical applications, a sample 1-2 was prepared by using the liquid crystal display device described in Example 1 of JP-A-10-48420, and Example 1 of JP-A-9-26572. , An optically anisotropic layer containing discotic liquid crystal molecules, an alignment film coated with polyvinyl alcohol, a VA-type liquid crystal display device shown in FIGS. 2 to 9 of JP-A-2000-154261, and JP-A-2000-154261.
Good performance was obtained when used in the OCB type liquid crystal display device shown in FIGS.

Example 16 Sample 16-2, which is the same as sample 1-2 of Example 1, except that the film thickness was set to 120 μm.
2 was produced. One of the obtained films is
No. 73736, Example 1 (back layer composition)
A first layer and a second layer were provided to produce a back layer having a cationic polymer as a conductive layer. Further, on the opposite side of the film base to which the obtained back layer was applied, Japanese Unexamined Patent Application Publication No.
Sample 105 of Example 1 described in JP-A-38568 was applied to prepare a silver halide color photographic light-sensitive material. The obtained color film was excellent in image quality and had no problem in handling.

[0082]

According to the present invention, it is possible to obtain a solution in which the cellulose ester is stably dissolved in an organic solvent other than the halogenated organic solvent. Further, thereby, a cellulose triacetate film having an excellent surface condition can be obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 1/10 C08L 1/10 G02B 5/30 G02B 5/30 G03C 1/795 G03C 1/795 // B29K 1:00 B29K 1:00 B29L 7:00 B29L 7:00 9:00 9:00 F term (reference) 2H023 FA01 FA13 2H049 BA02 BA06 BB49 BC22 4F071 AA09 AH16 BA02 BB02 BC01 4F205 AA01 AB07 AB11 AB14 AG01 AG03 GA07 GB02 GB26 GC02 GC07 GE22 GE24 4J002 AB021 DE137 DE147 DE237 DG047 DJ007 DJ017 DJ037 DJ047 EE038 EH146 EJ068 EU178 FD017 FD026 FD058

Claims (9)

[Claims] 1. A cellulose ester having a mannose / xylose molar ratio contained in a neutral constituent sugar component of 0.35 to 3.0 and a degree of substitution of cellulose with hydroxyl groups of the following (I) to (III): , A mixed solution comprising a release agent having an acid of pKa4 or less, methyl acetate, a ketone having 3 to 6 carbon atoms and an alcohol having 1 to 4 carbon atoms,
Cool to ~ -10 ° C and / or 70-200 ° C, 0.3 ~
A cellulose ester film produced by casting and drying from a cellulose ester solution obtained by heating at a high temperature and a high pressure of 30 MPa: (I) 2.6 ≦ A + B ≦ 3.0 (II) 2.0 ≦ A ≦ 3.0 (III) 0 ≦ B ≦ 0.8 [wherein A and B represent a substituent of an acyl group substituted by a hydroxyl group of cellulose, A represents a degree of substitution of an acetyl group, and B Is the degree of substitution of an acyl group having 3 to 22 carbon atoms]. 2. The method according to claim 1, wherein the total content of mannose and xylose contained in the neutral constituent sugar component is 1 to 5 mol%, and the cellulose ester contains 0.01 to 2 mass% of water. Cellulose ester film. 3. The cellulose ester film according to claim 1, wherein the ketone is acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, cyclopentanone or cyclohexanone, and the alcohol is methanol, ethanol, propanol or butanol. 4. The ratio of methyl acetate, ketone and alcohol is 20 to 90% by mass of methyl acetate and 5 to 50% of ketone.
The cellulose ester film according to claim 1, which is 5% by mass and 5 to 20% by mass of an alcohol. 5. A cellulose ester solution comprising: 0.1 to 20% by mass of a plasticizer based on cellulose ester; 0.001 to 5% by mass of an ultraviolet absorber based on cellulose ester; 0.0 for
2. The composition according to claim 1, wherein the release agent is contained in an amount of from 0.001 to 2% by mass based on the cellulose ester.
The cellulose ester film according to the above. 6. The cellulose ester film according to claim 1, which is a production process in which two or more cellulose ester solutions are co-cast in the casting process. 7. The cellulose ester film according to claim 1, which is stretched uniaxially or more. 8. An optical protective layer, which has a thickness of 10 to 10.
The cellulose ester film according to claim 1, which has a thickness of 200 µm. 9. The cellulose ester film according to claim 1, which is for a support of a silver halide photographic light-sensitive material and has a thickness of 30 to 250 μm.