TW200906942A - Optical film, process for producing optical film, polarizer, and liquid-crystal display - Google Patents

Abstract

An optical film which is formed from a material having a low melt viscosity and which is reduced in coloration and fluctuates little in retardation; a process for producing the optical film; a polarizer employing the optical film and having satisfactory durability over long; and a liquid-crystal display having a high contrast. The optical film is characterized by comprising a cellulose ester in which the kinds of substituents and the degrees of substitution therewith per one glucose unit of the cellulose ester satisfy all of the following relationships (1) to (3).; Relationship (1) 6.30=2OE+3OE=7.50 Relationship (2) 1.10=Y=1.50 Relationship (3) 0.35=Y6=0.50 [In the relationships, X represents the total of the average degrees of substitution with acetyl in the 2-, 3-, and 6-positions; Y represents the total of the average degrees of substitution with propionyl in the 2-, 3-, and 6-positions; and Y6 represents the average degree of substitution with propionyl in the 6-position.]

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical film comprising a cellulose ester, a method for producing an optical film, a polarizing plate using the optical film, and a liquid crystal display device. [Prior Art] An optical film made of a cellulose ester is mostly used as a support for protecting a negative film for photographs, because of its high transparency, low birefringence, and easy adhesion of polarizers. An optical film, a polarizing plate, or the like of a polarizer of a liquid crystal display device is used. In addition, as a liquid crystal display device, it can be used for various functional films such as a retardation film, a viewing angle expansion film, and an antireflection film for a plasma display, and can be used for various types of organic EL displays and the like. Functional film, etc. In recent years, the production volume of liquid crystal display devices which have been internally thinned and lightened has increased, and the demand has also increased. Moreover, the television using the liquid crystal display device can be thinned and lightened. It can produce a large-sized television that cannot be realized by a television using a cathode ray tube, and the demand for a polarizer and a polarizing plate protective film of the liquid crystal display device is also required. Increase. As a polarizing plate protective film, since it has excellent optical characteristics, an optical film can generally be used. These optical films have heretofore been produced exclusively by solution casting. The solution casting method is a film forming method in which a solution in which a cellulose vinegar is dissolved in a solvent is cast to obtain a film shape of -5-200906942, and the solvent is evaporated and dried to obtain a film. Since the film formed by the solution casting method has high planarity, it is possible to obtain a high-quality liquid crystal display device without unevenness. However, the solution casting method requires the use of a large amount of organic solvent, and the environmental load is also a problem. From the viewpoint of the solubility characteristics, the optical film is formed by using a halogen-based solvent having a large environmental load. Therefore, it is particularly required to reduce the amount of the solvent used, so that it is difficult to increase the production of the optical film by solution casting. thing. Therefore, a film forming method which does not use an organic solvent, for example, a film forming method by heating and melting is expected. Further, as an optical film used as a protective film for a polarizing plate of a liquid crystal display device, the cellulose triacetate film has been used in the past because of its low birefringence. The polarizing plate generally has a transparent resin layer laminated on both sides of the polarizing film made of iodine or a dye-adjusted polyvinyl alcohol film, and the cellulose triacetate film is often used as the transparent resin layer. use. However, in the case of solution casting film formation, the cellulose triacetate of the generally used cellulose ester is suitable for melt film formation, since the cellulose triacetate is decomposed and the starting temperature is lower than the melting initiation temperature. The cellulose ester is difficult to use for melt film formation. In recent years, cellulose esters have been substituted not only by an ethyl fluorenyl group but also by a specific ratio of a fluorenyl group or a butyl fluorenyl group, as a photograph for use in a silver salt (for example, refer to Patent Document 1) or a protective film for a polarizing plate (for example) For example, 'Reference Patent Documents 2 and 3', attempts have been made to melt such a cellulose ester into a film of -6-200906942. Thus, the cellulose ester is melted to form a film because the decomposition initiation temperature is higher than the melting initiation temperature. However, the cellulose ester is a material derived from a natural raw material, and thus contains a trace amount of metal ions and slightly contains metal ions or garbage mixed in the esterification step of cellulose. The removal of these trace metal ions or waste is finally removed by filtration through a filter during the film forming step of the optical film. In the past solution casting method, since the viscosity of the solution is low, there is no particular problem in filtration. However, since the film is formed by heating and melting, since the solvent is not used, the viscosity is high and the filtration time is long. Sexual barriers. On the one hand, if the temperature at the time of melt film formation is increased, the viscosity of the cellulose ester is lowered, so the filtration must be completed in a short time, and the productivity can be improved, but the cellulose ester is originally a resin which is weak to heat. The relationship between resin deterioration and productivity as trade-off has become a problem to be solved. Although the relationship of t r a d e - 〇 f f is attempted to be released (for example, refer to Patent Documents 4 and 5), the deterioration of the alkalization suitability described below is obtained as a result. On the other hand, it is known to add a specific deterioration preventing agent when the cellulose ester is melt-formed (for example, refer to Patent Document 6). Basically, by adding a deterioration preventing agent, deterioration of chemical properties of the cellulose ester (coloring, reduction in molecular weight) can be prevented, but if the combination of the cellulose ester and the deterioration preventing agent is unsuitable, a counter effect is obtained, in other words, a cellulose ester The result of deterioration caused by chemical characteristics becomes a problem to be solved. Depending on the type of the deterioration preventing agent to be used, the deterioration of the chemical characteristics may not occur, but the optical characteristics may be deteriorated. -7- 200906942 In addition, similarly to other resins, the structure and optical properties of cellulose esters are closely related, so the types of substituents which have a large influence on the structure of cellulose esters, and the degree of substitution The selection of an appropriate deterioration preventing agent corresponding to the position of the substituent is an important matter. The cellulose ester substituted by the above-mentioned propyl fluorenyl or butyl fluorenyl group is such that when the degree of substitution of the fluorenyl group or the butyl fluorenyl group is increased for the acetamidine group, the melt viscosity is reduced as compared with the same temperature, which is advantageous for productivity. However, most have the following problems. Generally, when a protective film made of a cellulose film is bonded to a polarizer to form a polarizing plate, since the water-soluble adhesive is easily applied, the film is immersed in a high-temperature, high-concentration lye to carry out a so-called alkali. After the treatment, the surface of the film is hydrophilized and coated with an adhesive, and then laminated with a polarizer. From the viewpoint of the adhesion to the above-mentioned polarizers, the transparent resin film for the polarizing plate protective film is made of triethylenesulfonyl cellulose, and one of the reasons for not being substituted for other films is that even the polyester film is gathered. Other polymer films such as a carbonate film or a ring-shaped thin resin film are subjected to an inspection process, and the adhesion to a polarizer cannot be obtained. Applicable to the above-mentioned melt film-forming, not only an epoxy group-substituted one, but also an optical film substituted by a fluorenyl group or a butyl group, which has an easy adhesion compared with a polymer film other than cellulose vinegar. When the degree of substitution of the fluorenyl group or the butyl group is too high, alkalization treatment is difficult, and as a result, the adhesion is deteriorated. In particular, when the propylene group is compared with the butyl group, even if the carbon number is only one -8-200906942, it is difficult to substantially perform the alkalization treatment by combining the butyl group. In the past, the suitability of alkalization was also related to the tradeability of tradeability. Up to now, the importance of cost reduction and productivity has been increasing to the present state, and the time for the alkalization step is expected to be shortened. The use of a film that is difficult to alkalinize is a fatal problem. As described above, in the past, a problem solving method in the production of a protective film (for example, refer to Patent Documents 4 and 5) or a problem solving method in the production of a polarizing plate (for example, refer to Patent Document 7) is known, but the effects are not sufficient. Moreover, the method of solving both at the same time has not been proposed. Therefore, the optical film and the optical film formed by the cellulose ester which has excellent environmental suitability and good quality and productivity while replacing the triethylenesulfonated cellulose film formed by the solution casting method, The appearance of a polarizing plate and a liquid crystal display device using the optical film is expected to be the current state of the art. [Patent Document 1] JP-A-2006-111796 (Patent Document 3) JP-A-2006-111796 (Patent Document 4) JP-A-2006- 1 [Patent Document 5] JP-A-2006-348428 (Patent Document 7) JP-A-2006-241428 [Patent Document 7] JP-A-2002-242A 9-200906942 Problem to be Solved by the Invention The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical film which is excellent in environmental compatibility, has good productivity, and is excellent in optical characteristics, and is more specifically melted. The film has a small melt viscosity, a small amount of coloring, an optical film having a small variation in retention enthalpy, and a polarizing plate which is excellent in durability after use for a long period of time and a liquid crystal display device having a relatively high contrast. The above object of the present invention is achieved by the following constitution. 1. An optical film comprising a cellulose ester, wherein the cellulose ester is characterized in that the type of the substituent per 1 glucose unit of the cellulose ester and the degree of substitution satisfy the conditions of the following formulas (1) to (3) Optical film. Equation (1) 6.30$2χΧ+3χΥ$7·50 Formula (2) 1 . 1 0 ^ Y ^ 1 .50 Equation (3) 0.30SY6S0.50 [where X represents the 2nd, 3rd, and The average degree of substitution of the ethyl sulfhydryl group at the 6th position is S, the Y table is not the sum of the average degree of substitution of the 2nd, 3rd, and 6th propyl groups, and Y6 is represented by the 6th place. The average degree of substitution of thiol. 2. The optical film according to the above 1 characterized in that the weight average molecular weight of the cellulose ester is i5 Å or more and less than 250,000. 3. The optical film described in the above 1 or 2 is characterized in that the optical film is a phenol-based compound. 4. The optical film described in any one of the above 1 to 3 is characterized in that the optical film is a film containing a pity compound. -10-200906942 5_ The optical film is an alkyl radical-trapping agent. The optical film according to any one of the above items 1 to 4, wherein the optical compound is a hindered phenol compound, and the optical film described in the above item 3 to 5. The optical film described in any one of 4 to 6 is described in detail in the case where the phosphorus-based antioxidant compound is a phosphinate-based compound. Formula (1)

[In the formula, R! represents a hydrogen atom or an alkyl group having 1 to 1 carbon atom, and each of the cores independently represents a carbon number of 1 to 8. 〕 General (2)

In the formula 'foot! 2~:!^5 each independently represents a hydrogen atom or a substituent, and Ri6 represents a hydrogen atom or a substituent represents an integer of 1 to 4. When ^ is 1, RM Table -11 - 200906942 shows a substituent, and when η is an integer of 2 to 4, Rh represents a linking group of 2 to 4 valence. And 'the substituent represents an alkyl group, a cycloalkyl group, an aryl group, a decylamino group, an alkylthio group, a arylthio group, a stilbene group, a dentate atom, a block group 'anthracene ring group, a sulfonyl group, Arylsulfonyl, alkylsulfinyl, arylsulfinyl, phosphinium, fluorenyl, aminomethylguanidino, sulfonyl, sulfonylamino, cyano 'alkoxy, Aryloxy, heterocyclooxy 'carbomethoxyoxy, decyloxy, sulfonic acid, sulfonic acid salt, aminocarbonyloxy, amine, anilino, imido, ureido, alkoxycarbonyl Amine, alkoxycarbonyl, aryloxycarbonyl, heterocyclic thio, thioureido, carboxy, carboxylic acid salt, hydroxy, thiol, or nitro. A method for producing an optical film which is produced by the melt casting method of the optical film according to any one of the above items 1 to 8. 1) A polarizing plate characterized by having the optical film described in any one of the above items 1 to 8 on at least one side of the polarizer.液晶 A liquid crystal display device characterized by using the polarizing plate described in the above 10 for at least one of liquid crystal cells. That is, the inventors of the present invention have solved the above problems, and in the detailed review process, the hydroxyl groups at the 2nd, 3rd, and 6th positions of the glucose unit constituting the cellulose ester are derived from an ethyl group and a propyl group. As a result of reviewing the substituted cellulose ester, it was found that when the substituted state (average degree of substitution, substitution position) of the ethyl hydrazino group and the propyl fluorene group is within the constitutional range of the present invention, the present invention can be solved by solving the above problems. [Effects of the Invention] -12-200906942 The present invention provides an optical film excellent in environmental suitability, good in productivity, and excellent in optical characteristics, and more specifically provides a melt viscosity at a time of melt film formation, less coloring, and retention of 値The optical film having a small variation, the method for producing the optical film, and the use of the optical film can achieve a polarizing plate which is excellent in durability over a long period of time and a liquid crystal display device having a high contrast. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best mode for carrying out the invention will be described in detail, but the invention is not limited thereto. The present invention provides an optical film which is excellent in productivity and excellent in optical characteristics. When such an optical film is used, a high-quality optical film such as a protective film for a polarizing plate, an antireflection film, or a retardation film can be obtained, and a liquid crystal display device which is inferior in quality can be obtained. The optical film of the present invention may be an optical film produced by any one of a melt casting method and a melt casting method, but in view of environmental suitability, a melt casting method is preferred. In the present invention, after the optical film cast by the solution is dissolved in a solvent, the optical film forming material is heated to be in a flowable molten state, and the casting is defined as a melt casting method. The molding method by heating and melting is more specifically classified into a melt extrusion molding method, a pressure molding method, a blow molding method, an injection molding method, a blow molding method, an extension molding method, and the like. Among them, an optical film excellent in mechanical strength and surface precision is preferable, and a melt extrusion method is preferred. In the present invention, after the optical film forming material is heated, it exhibits a flow of -13-200906942, and then the film is extruded on the transfer or the endless conveyor belt. The method of the melt casting method of the present invention is a preferred state. kind. Therefore, the optical film of the present invention is an optical film forming material containing at least one of the following non-cellulosic vinegars, and is preferably heated and melted at a melting temperature of from 200 ° C to 270 ° C. An optical film formed by a melt casting method is preferred. Hereinafter, the optical film of the present invention will be described. "Cellulose Ester" cellulose has one '3' total of 3 hydroxyl groups in the 2nd, 3rd, and 6th positions of 1 glucose unit, and the degree of substitution is represented by the average of sulfhydryl groups on 1 glucose unit. How many numbers are combined at any position, so the portion with the 'maximum degree of substitution 3.00' that is not substituted by the above thiol group generally exists as a hydroxyl group. Such a cellulose base is partially or wholly replaced by a thiol group as a cellulose ester. The cellulose ester of the present invention has a total degree of substitution of the second, third, and sixth thiol groups as X, and the second, third, and sixth propyl groups. When the average degree of substitution is γ, and the average degree of substitution of the propyl group at the 6th position is Y6, the cellulose esters of the following formulas (1) to (3) are simultaneously satisfied (hereinafter, the average degree of substitution is simply referred to as Degree of substitution) ° Such a cellulose ester is generally referred to as cellulose acetate propionate. -14- 200906942 In addition, if only one of the following formulas or neither of them can solve the above problem, it is important to satisfy three at the same time. Formula (1) 6.30S2XX+ 3XYS7.50 Formula (2) 1.10SYS1.50 Formula (3) 0.30SY6S0.50 wherein 6.70$2xX+3xYS7.10' in the formula (1) is more effective in the effect of the present invention. good. In the formula (2), the effect of the present invention can be exerted at 1.20 SYS 1.40, which is preferable. In the formula (3), the effect of the present invention can be exerted at 0.35 SY6S 0.45, which is preferable. Further, information on the degree of substitution and substitution position of the ethyl thiol group and the propyl group can be obtained by the method described below. Next, the measurement method of the degree of substitution and the position of substitution of the thiol group (ethyl fluorenyl group and propyl fluorenyl group) of the cellulose ester used in the present invention will be described in detail. The method for determining the degree of substitution of each position of the thiol-based glucose unit of the present invention can be carried out by the paper by Y. Tezuka & Y. Tsuchiya (Carbohydrate Research, Vol. 273, pp. 83-91 (1999)) The 13C-NMR method described is carried out. When using this method, the 13C-NMR information of the thiol group and the information of the propyl group can be clearly distinguished, and the messages of the 2nd, 3rd, and 6th positions can be divided into three close peaks for identification. The degree of substitution is known from the height of the peak. And 'the degree of substitution of the acetyl group and the propyl group can be confirmed by reference to the enthalpy obtained by the method specified in ASTM D8 17-96. -15- 200906942 Next, for the problem to be solved, the necessity of satisfying the above three formulas (1) to (3) must be explained. According to the review by the present inventors, 'the total average carbon number of the sulfhydryl group substituted by 1 per glucose unit of the cellulose ester (2 χχ + 3 χ γ (the ethane group is 2 carbon atoms, C) is known about the melt viscosity and the conformability. The sulfhydryl group has a carbon number of 3. The following is only referred to as the total carbon number), the degree of substitution of the fluorenyl group (Υ), and the degree of substitution of the propyl group of the sixth group (Υ6) are closely related. On the one hand, when the cellulose ester is substituted by a fluorenyl group having a larger carbon number than a fluorenyl group, for example, a butyl group having a carbon number of 4, it is advantageous for the melt viscosity, but the alkalization suitability is greatly deteriorated even if the substitution of the butyl group is adjusted. Degrees and replacement positions are also completely unimproved. The inventors considered that the melt viscosity is determined by the interaction of cellulose esters with each other. In other words, considering the influence of the interaction force, for example, when it is an electronic effect, it is important that the hydroxyl-related hydrogen bond remaining in the cellulose ester is important, and when it is a stereoscopic effect, the arrangement regularity of the thiol group of the glucose unit is not Regularity is important. A higher volume of the fluorenyl group compared to the acetamidine group can achieve this remarkable effect. Therefore, in the cellulose ester of the present invention, it is particularly important to control the total carbon number (2 χ χ + 3 χΥ) and the degree of substitution (γ) of the propyl group. From the viewpoint of alkalization and adhesion to a polarizer, the chemical compatibility of the cellulose ester has a very large influence on the alkali hydrolysis property of the cellulose ester and the number of remaining hydroxyl groups after alkalization. Therefore, the difference between the type of the base and the degree of substitution is very large. This-16-200906942 is still the same as the above melt viscosity, and the degree of substitution for the total carbon number (2 χ X + 3 χ Υ ) and propyl thiol groups. The control of (Y) is particularly important. When the total carbon number is 6.3 hours, the melt viscosity becomes high, which is presumed to be extremely related to the residual hydroxyl group. On the other hand, when the total carbon number is larger than 7.5, the alkalinity suitability is deteriorated, which is presumed to be caused by the small number of hydroxyl groups remaining after alkalization. Further, if the degree of substitution of the propyl group is 1 to 10 hours, the melt viscosity becomes high. This is presumed to be a large influence of the acetyl group, and the properties are similar to those of the triethyl fluorenyl cellulose. On the other hand, when Y is larger than 1.50, it is difficult to alkalinize, which is presumed to be caused by a lower alkali hydrolysis rate of the lower propyl group than the acetamyl group. And among the three hydroxyl groups of the 'glucose unit, the number of carbon atoms is unique to the other sixth position. The sulfhydryl reactivity in the synthesis of cellulose ester from cellulose and the reactivity in alkalization (alkali hydrolysis) have considerable differences. Further, the sixth position is that only one carbon is removed from the pyranose ring forming the glucose unit. This stereo structure has a very large influence on the interaction between the cellulose esters. In particular, the difference between them is more pronounced when substituted with a higher volume of the fluorenyl group than the acetamidine group. Therefore, the degree of substitution (γ 6 ) of the propylene group controlling the third position in the cellulose ester of the present invention is also particularly important. Although the details are not clear, it has almost the same total carbon number within the scope of the present invention. And when the cellulose esters having the same propyl ketone group substitution of -17 to 200906942 degrees within the scope of the present invention are compared with each other, it is surprisingly found that the degree of substitution of the propyl group at the sixth position is outside the range of the invention, in other words, the upper limit In either case of the degree of substitution or the degree of substitution less than the lower limit, the melt viscosity is high and the alkalinity suitability is also deteriorated. As a result of the above detailed review, the inventors have concluded that when all of the above formulas (1) to (3) are satisfied, the productivity of the optical film can be improved by lowering the melt viscosity, and it is used for polarizing plate production. The two basicizations of alkalinity are necessary. Next, the synthesis method of the cellulose ester used in the present invention is described. The cellulose of the cellulose ester used in the present invention may be wood pulp or cotton linters, and the wood pulp may be a conifer or a broad-leaved tree, wherein the conifer Preferably. From the viewpoint of the peeling property at the time of film formation, cotton linters are preferred. The cellulose esters prepared from each other may be suitably mixed or used alone. For example, 'Using cellulose ester from cotton wool: cellulose ester from wood pulp (coniferous tree): the ratio of cellulose ester from wood pulp (broadleaf tree) is 1〇〇: 〇: 0, 90: 1〇: 〇 , 85: 15: 0, 50: 50 · 0 ' 20 - 80 : 〇> 1 〇; 9〇: 〇. 〇: ι〇〇:〇>〇:〇: ι〇〇,80· 10- 10 85: 〇: 15, 40: 30: 30. It is known that the cellulose ester of the present invention is not satisfactory only when it is synthesized by referring to a known method, and it is necessary to go through a special process. For example, 'the hydroxyl group of the raw material cellulose is acetic anhydride and propionic anhydride, and it is acetylated and propylated by a hanging method, and can be substituted with an ethyl hydrazide or a propyl hydrazine group, and the acetic anhydride used, And the amount of propionic anhydride can be changed to -18-200906942, the degree of substitution of the acetamidine group, the degree of substitution of the propyl fluorenyl group, the total degree of substitution 〇, and the cellulose ester having a higher degree of substitution at the 6th position The synthesis is described in each of the publications of JP-A No. 1 1 - 5 8 5 1 or JP-A-2002-2 1 23 3 8. However, with reference to these methods, it is not easy and free to control the sixth position. Base substitution degree. In the past, in the synthesis of a cellulose ester in which only an ethyl group was substituted, the degree of substitution of the second and third positions of the ethylenic group was higher than that of the sixth group. This is because the sulfuric acid used in the catalyst first reacts with the sixth position with less steric hindrance (the formation of sulfate), and as a result, the second and third positions having a higher vacancy ratio with the acetyl group are easily reacted. Therefore. However, the so-called sulfate ester is dissociated under an equilibrium reaction, and is more susceptible to the steric hindrance of cellulose than the acetamidine group, and is easily reacted with the sixth position having a small steric hindrance, resulting in the sixth position. The degree of substitution of the propyl group is easier to increase. In the present invention, sulfuric acid is used as a catalyst, acetic acid is used as a raw material, and acetic acid anhydride and propionic anhydride are used for acetylation and propylation, and there is no difference in the past, but by using acetic acid, and C The addition of the acid anhydride is carried out several times while changing the ratio of both, and the degree of substitution of the propyl group at the 6th position can be freely controlled. Using the above method, the cellulose ester of the present invention which satisfies the above formulas (1) to (3) can be synthesized. The cellulose ester of the present invention is not particularly limited, and has a weight average molecular weight (Mw) of from 150,000 to 250,000 to 19,906,046, and a weight average molecular weight of from 180,000 to 230,000 is more preferable, and has a weight of 190,000. The weight average molecular weight of ~220,000 is the best. When the weight average molecular weight is within the above preferred range, the melt viscosity is not excessively high, and the resulting film strength is lowered, which is preferable. And the cellulose ester used in the present invention is preferably a weight average molecular weight (Mw) / number average molecular weight (?η) ratio of 1.3 to 5.5, particularly preferably 1 to 5 to 5.0', more preferably 1.7 to 4.0, and most preferably It is a cellulose ester of 2.0 to 3.5. When Mw/Mn exceeds 5.5, the viscosity tends to be high, and the melt filterability tends to be lowered, which is not preferable. On the other hand, in view of industrial manufacturing characteristics, it is preferable to be 1.3 or more. Further, 'Mw and Mw/Mn can be calculated by gel permeation chromatography (GPC) in the following manner. The measurement conditions are as follows. Solvent: Tetrahydrofuran unit: HLC-8220 (manufactured by Tosoh Co., Ltd.) Column: TSKgel SuperHM-M (manufactured by Tosoh Co., Ltd.) Column temperature: 40 °C Sample concentration: 0.1% by mass Injection amount: 1 0 // 1 Flow·· 0 · 6 m 1 / mi η proofreading curve: using standard polystyrene·· PS” (P〇lymer

Proofreading curve obtained from Laboratories Inc., Mw = 2,560,000 to 580 of 9 samples. -20- 200906942 The alkaline earth metal content of the cellulose ester of the present invention is preferably in the range of 1 to 50 ppm. When the content of the alkaline earth metal of the cellulose ester is in the range of 1 to 5 〇 ppm, the increase in the adhesion of the protrusion (1 i P ) is not increased, and the cut portion is not broken during the heat extension or after the heat extension. It is preferred to achieve the effects of the present invention. Further, in the present invention, the content of the alkaline earth metal of the cellulose ester is preferably in the range of 1 to 30 ppm. The so-called alkaline earth metal is a total content of Ca and Mg, and can be measured by an X-ray photoelectron spectroscopy analyzer (XP S ). The residual sulfuric acid content in the cellulose ester of the present invention is preferably in the range of 0.1 to 45 ppm in terms of sulfur element. It may contain the form of these salts. When the residual sulfuric acid content exceeds 45 ppm, the deposit of the molded portion of the mold at the time of hot melting may increase. Moreover, it is not preferable because it is easy to break during the hot stretching or after the heat stretching. 较少 It is less preferable, but when it is less than 0·1, it is not easy to break, but the reason is unknown. A range of 1 to 30 ppm is more preferable. The residual sulfuric acid content can be determined by the method specified in ASTM D817-96. The free acid content in the cellulose ester of the present invention is preferably from 1 to 50 〇 PPm. In the above range, the attachment of the mold protrusion (liP) portion does not increase -21 - 200906942 and is not easily broken. Further, in the present invention, the range of 1 to 100 ppm is preferable, and it is less likely to be broken. It is particularly preferably in the range of 1 to 7 〇 ppm. The free acid content can be determined by the method specified in ASTM D817-96. When the synthetic cellulose ester is washed and compared with the solution casting method, it can be further sufficiently carried out so that the residual alkaline earth metal content, the residual sulfuric acid content, and the residual acid content are preferably in the above range. In addition to the washing and dewatering of the cellulose ester, a weak solvent such as methanol or ethanol, or a mixed solvent of a weak solvent and a good solvent which is a weak solvent as a result can be used to remove inorganic substances other than residual acid and low molecular weight. The organic impurities and the washing of the cellulose ester can be carried out in the presence of a deterioration preventing agent, and the heat resistance and film stability of the cellulose ester can be improved. The deterioration preventing agent to be used is only a compound which can suppress the deterioration of the cellulose ester caused by the radical which is inactivated in the cellulose ester or the addition of oxygen to the radical of the cellulose ester. In particular, a hindered phenol-based compound, a hindered amine-based compound, or a phosphite-based compound is preferred, and the heat resistance, mechanical properties, optical properties, and the like of the cellulose ester are desired to be improved after dissolution of the good solvent of the cellulose ester. The low molecular weight component of the cellulose ester and other impurities can be removed by reprecipitation in a weak solvent, filtration, or suspension stirring in a weak solvent followed by filtration. In this case, it is preferably carried out in the presence of the deterioration preventing agent-22-200906942 in the same manner as the washing of the cellulose ester. The deterioration preventing agent used for washing the cellulose ester can remain in the cellulose ester after washing. The residual amount is preferably 0.01 to 2000 ppm, preferably 0.05 to 1000 ppm. More preferably, it is 0.1 to 100 ppm. Further, after the reprecipitation treatment of the cellulose ester, other polymers or low molecular compounds may be added. Since the cellulose ester of the present invention is used for melt film formation, the cellulose ester itself is excellent in heat resistance, and the cellulose ester before heating and melting is preferably 1% by mass under the air. The temperature Td (1.0) is preferably higher. . When the cellulose ester is to be melt-formed, Td (1 · 0 ) is preferably 260 ° C or more, Td ( 1 · 0 ) is preferably 270 ° C or more, and more preferably 280 ° C or more. In the synthesis of cellulose ester on the Td (1.0) of the cellulose ester, in the process of filtering and washing the cellulose ester finally taken out, the pH of the washing liquid is sufficiently washed with water until the pH of the washing liquid is neutral. improve. However, although the detailed reason is not fully understood, depending on the type of the cellulose ester, the mechanical properties such as breakage are likely to be deteriorated during the transition washing, and the cellulose ester of the above formulas (1) to (3) of the present invention is simultaneously satisfied. It was found that the deterioration of mechanical properties did not occur with washing. Further, the cellulose ester which does not satisfy any of the above formulas (1) to (3) of the present invention has deterioration in heat resistance even when Td (1.0) is 2 70 °C or higher. Moreover, the 1% mass reduction temperature Td(l_0) in the air can be measured by a differential thermogravimetric analysis (TG-DTA) device, generally -23-200906942. The cellulose ester contains a trace amount of water, so the determination is Must pay attention. Specifically, the sample was temporarily held at 100 ° C. The method of measuring the decrease in mass caused by the increase in temperature at the point after the deterioration of the mass due to the evaporation of moisture was confirmed. However, there is no upper limit for Td (1.0), although it is presumed that the higher the better, but the burden of the washing step to avoid the cellulose ester is too large, and the practical upper limit is 30,000 to 3 1 0. (: ° When the cellulose ester in the optical film is in the range of 70% by mass to 99% by mass, the film exhibits excellent melt castability and stability in the presence of an additive such as a deterioration preventing agent, a plasticizer, and an ultraviolet absorber to be described later. When the content of the cellulose ester is in the range of 70% by mass to 99% by mass, the additive is not bleed, and the mechanical strength of the film can be improved, and the effect of the present invention is preferable. When the amount of the other additives necessary for the optical film is 1.0% by mass or more, the desired physical properties are satisfied, and the content of the cellulose ester is preferably 80 to 95% by mass. The optical film of the present invention is a cellulose ester. The polymer component other than the polymer component may be suitably mixed. The mixed polymer component and the cellulose ester are excellent in compatibility, and the transmittance when used as a film is 80% or more, and more preferably 90% or more. Preferably, it is 92% or more. In another embodiment, the cellulose ester of the raw material may be used at least once after the solvent is dissolved, and the solvent is dried. The terminator 'plasticizer, ultraviolet absorber, and anti--24-200906942 At least one or more kinds of photo-agents are simultaneously dissolved in the ester. As a solvent, it can be used as a good solvent for the solution casting method such as dichloromethyl ring or the like. A weak solvent such as an alcohol, which is enthalpy to 80 ° C or higher during the dissolution process. When such a cellulose ester is used, it is easy to make the optical properties uniform. "Determination inhibitor" The deterioration inhibitor is caused by decomposition of the polymer. The chemical action suppressing film is particularly 200. (: a system for forming, decomposing, and degrading at a high temperature, and preventing degradation by using an optical film, preventing or suppressing decomposition of free radicals caused by light or heat, Further, the volatile component caused by the coloring or the decomposition of the material is prevented from being a deterioration preventing agent. For example, a exemplifying agent, an acid scavenger, and a metal inerting agent are described in JP-A-3-199201, JP-A-5-149789 Japanese Unexamined Patent Publication No. Hei 6-107854, etc. After the solvent, the dried cellulose alkane, methyl acetate, dioxane, and methanol and ethanol can be used at -2 0 °C. When the material is cooled or heated in a uniformly molten state, the material is added by heat, oxygen, moisture, acid, etc. The optical fiber of the present invention is thin, so that it is an acid which is easily decomposed in the case where the polymer agent is contained in the optical film. The anti-oxidation agent, the hindered amine light-amplifier, etc., which are included in the decomposition reaction of the gene, such as the decomposition reaction of the gene, and the molecular weight reduction, are not limited thereto. This is forged, and the special product is 5-1907073. In the case of the purpose of the present invention, it is preferable to contain an antioxidant as a deterioration preventing agent in the optical film. The optical film forming material of the present invention is preferably used in the above-mentioned Japanese Patent Application No. H-25-200906942. The amount of the deterioration preventing agent to be used may be at least one or more, and the amount of the deterioration preventing agent added is preferably 0.01% by mass or more and 10% by mass or less, preferably 0.1% by mass. % or more and 5.0% by mass or less, more preferably 〇 2% by mass or more and 2.0% by mass or less. Further, when the amount of the deterioration preventing agent added is in the above-mentioned range of the addition amount, the transparency of the optical film can be improved from the viewpoint of the compatibility with the cellulose ester, and the optical film is not brittle and is not preferable. The optical film can be divided into one or a plurality of kinds of particles and stored after the material is deteriorated or hygroscopic. The granulation is such that the miscibility or compatibility of the melt at the time of heating can be improved, or the optical uniformity of the obtained film can be ensured. When the optical film is heated and melted, it can be used in the subsequent step when it is heated and melted, and when it is used as a product for the consumer, if the above-mentioned deterioration preventing agent is present, the deterioration of the strength or optical transparency due to deterioration or decomposition of the material is normal. It is preferred to reduce 'or maintain the inherent strength of the material. When the optical film shows a significant deterioration upon heating, coloring cannot be used as an optical film. Further, when used as an optical compensation film for a liquid crystal display device, the retention enthalpy application step (extension step) is performed after the casting step, but when the optical film is significantly deteriorated by heating, the formed film becomes brittle. The break in the middle is prone to the 'inability to express the retention of the optical compensation film -26- 200906942

Further, when used as a polarizing plate protective film for a liquid crystal display device, deterioration of the optical film causes a barrier to bonding with a polarizer, which is not preferable. Therefore, the above-mentioned deterioration preventing agent is used to suppress the formation of the coloring matter in the visible light region during heating and melting, or to suppress or eliminate the volatilization caused by the decomposition of the material constituting the film after the heating and melting and the heating and melting. The rate or smog reduction is preferable as the deterioration of the optical film. The display image of the liquid crystal display device of the present invention is preferably used when the optical film of the present invention is used, and if the haze exceeds 1%, it is preferable. The haze is less than 1% 'better than 0. 5 %. Further, as the coloring property index, a yellowness (yellow index YI) can be used, preferably 3.0 or less, more preferably 1 or less. The yellowness is measured in accordance with JIS-K-7 1 0 3 . In the storage or film forming step of the above optical film, the deterioration reaction caused by oxygen or water in the air is simultaneously generated. At this time, the purpose of the stabilization of the above-mentioned deterioration preventing agent and the reduction of the humidity and the oxygen concentration in the air are all preferable in order to achieve the best of the present invention. As an inert gas in the prior art, the use of nitrogen or argon gas, the decompression operation under reduced pressure to vacuum, and the operation in a closed environment may be employed, and at least one of them may be used in combination with the stabilizer. It is preferable to reduce the deterioration of the material by reducing the probability of contact of the optical film with oxygen in the air. Further, the optical film of the present invention can be used as a polarizing plate protective film application -27-200906942, and thus the above-mentioned optical film is improved from the viewpoint of improving the storage stability with respect to the polarizer of the polarizing plate and the polarizing plate of the present invention. The presence of a deterioration preventive agent also plays an important role. In the liquid crystal display device using the polarizing plate of the present invention, when the deterioration preventing agent is present in the optical film of the present invention, the temporal storage property of the optical film can be improved from the viewpoint of suppressing the deterioration or deterioration. In the display quality improvement of the liquid crystal display device, it is preferable that the optical compensation design can exhibit its function over a long period of time. <<Antioxidant>> The cellulose ester is not only hot at a high temperature but also decomposes by oxygen. Therefore, it is preferable that the optical film of the present invention contains an antioxidant as a deterioration preventing agent. The antioxidant which is useful in the present invention is not particularly limited as long as it can suppress deterioration of the optical film caused by oxygen, and examples thereof include a phenol compound, a phosphorus compound, a sulfur compound, and an alkyl group. A radical scavenger, a peroxide decomposer, an oxygen scavenger, and the like. In addition, it is preferable to use a phenolic compound, a phosphorus compound, or an alkyl radical scavenger, and it is preferable to use a combination of a phenolic compound and a phosphorus compound, and use a phenolic compound, a phosphorus compound, and an alkyl radical. The combination of the three capture agents is optimal. By adding these compounds, not only the transparency, heat resistance and the like are not lowered, but the coloring or strength reduction of the molded body due to heat or thermal oxidative degradation during melt molding can be prevented. -28- 200906942 These antioxidants may be used singly or in combination of two or more kinds, and the amount thereof is appropriately selected so as not to impair the object of the present invention. For the quality of the cellulose ester of the present invention, 〇·01 The mass% or more is preferably 10% by mass or less, preferably 0.1% by mass or more and 5% by mass or less, more preferably 0.2% by mass or more and 2.0% by mass or less. (Phenol-based compound) The phenol-based compound is a known compound, and may be, for example, an alkyl-substituted phenol such as mono-t-butyl hydrazine or p-(1,1,3,3-tetramethylbutyl)phenol. The 2,6-dialkylphenol derivative compound and the so-called hindered phenol compound described in the columns 12 to 14 of the specification of U.S. Patent No. 4,839,4,5, wherein a hindered phenol compound is preferred. Specific examples of the hindered phenol phenol-based compound include η-octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate and η-octadecyl group. 3-(3,5-di-t-butyl-4-hydroxyphenyl)-acrylate, η-octadecyl 3,5-di-t-butyl-4-hydroxybenzoate, η- Hexyl 3,5-di-t-butyl-4-hydroxyphenyl benzoate, η-lauryl 3,5-di-t-butyl-tetra-hydroxyphenyl benzoate, new laurel 3-(3,5-di-t-t-butyl-4-hydroxyphenyl)propionate, lauryl hydrazine (3,5-di-t-butyl-tetra-hydroxyphenyl)propionate, Ethyl α - (4 -hydroxy-3,5-di-t-butylphenyl) isobutyrate, octadecyl α - (4-hydroxy-3,5-di-t-butylphenyl) Isobutyrate, octadecyl α — (4-hydroxy-3,5-di-t~butyl-4-hydroxyphenyl)propionate, 2~(n-octylsulfanyl)ethyl 3, 5-二-29- 200906942 One t-butyl-4-hydroxyl-benzoate, 2-(η-octylsulfanyl)ethyl 3,5-di-t Butyl-4-hydroxyl-phenyl acrylate, 2-(η-yttrium-based thio)ethyl 3,5- ___ — t-butyl-tetra-phenyl-phenylpropionate, 2_(η- Octadecylthio)ethyl 3,5-di-t-butyl-4-hydroxyl-benzoate, 2-(2-hydroxyethylsulfanyl)ethyl 3,5-di-t-butyl 4- 4-hydroxybenzoate, diethyl diol di-(3,5-di-t-butyl-tetra-hydroxy-phenyl)propionate, 2-(η-octadecylsulfide) Ethyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, stearylamine hydrazine, hydrazine-bis-[Ethyl 3-(3,5-di-t Monobutyl- 4-hydroxyphenyl)propionate], η-butylimine N,N-bis-[Ethyl 3-(3,5-di-t-butyl-4-hydroxyphenyl) Propionate], 2-(2_stearyloxyethylthio)ethyl 3,5-di-t-butyl- 4-hydroxybenzoate, 2-(2-stearyloxy) Ethylthio)ethyl 7-(3-methyl-5-t-butyl-4-hydroxyphenyl)heptanoate, 1,2-propanediol di-[3 - (3,5-di-tButyl-4-hydroxyphenyl)propionate], ethylene glycol bis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], neopentyl glycol Bis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], ethylene glycol di-(3,5-di-t-butyl-4-hydroxyphenyl) Acrylate), glycerol-1-l-octadecanoate-2,3-di-(3,5-di-t-butyl-4-hydroxyphenyl acrylate), pentaerythritol-[3- (3',5'-di-t-butyl- 4'-hydroxyphenyl)propionate], 3,9-bis-{2 -[3-(3-tert-butyl-4-hydroxy- 5-methylphenyl)propanyloxy]-1,1-dimethylethyl} — 2,4,8,10 —tetraoxa-spiro-[5.5]undecane, -30- 200906942 i 1,1,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3 , 5-di-t-butyl-4-hydroxyphenyl)propionate], 2-hydroxyethyl 7-(3-methyl-5-t-butyl-4-hydroxyphenyl)propionate, 2 _ stearyloxyethyl 7_(3-methyl~5-t~butyl-4-hydroxyphenyl)heptanoate, 1,6-η-hexanediol bis[(3',5'- Di-1,4-butyl-4-hydroxyphenyl)propionate], pentaerythritol monoterpene (3,5-di-t-t-butyl-4-hydroxyhydrocinnamate). The above-mentioned compound of the type 'is, for example, the trade names of "IRgaNOX 1 076" and "IRGANOX 1010" available from Ciba Specialty Chemicals Co., Ltd. (Phosphorus-based compound) The phosphorus-based compound which is useful in the present invention may, for example, be a phosphite-based compound or a phosphonite-based compound. Specific examples of the phosphite-based compound include triphenyl phosphite, diphenylisodecyl phosphite, phenyl di-isodecyl phosphite, and decyl (nonylphenyl) subscale. Acid ester, ginseng (di-nonylphenyl) phosphite, ginseng (2,4 1-2 t-butylphenyl) phosphite sorbate, ginseng (2,4-di-t-butyl-5- Methylphenyl)phosphite, 1〇-(3,5-di-t-butyl-4-hydroxybenzyl)-9,1〇-dihydro--9-oxo-10-phosphine- 10-oxide, 6-[3_(3-t-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,1〇41_t-butyl_. Monobenzo[d,f][l,3,2] _. A DIOXAPHOPHEPINE, tridecyl phosphite, etc. monophosphite-31 - 200906942 compound; 4,4'-butylene-double (3 -methyl-6-t-butylphenyl-denti-3-alkyl phosphite), 4,4'-isopropylidene-bis(phenyl-dialkyl (C12~C15) phosphorous acid a bisphosphite compound such as an ester; The phosphite-based compound of the above type may be, for example, "Sumilizer GP" of Sumitomo Chemical Co., Ltd., ADK STAB PEP-24G of ADEKA, "ADK STAB PEP-36,, "ADK STAB 3010", " The trade names of ADK STAB HP-10" and "ADK STAB 21 12" are available. Specific examples of the phosphonite-based compound include dimethyl-phenylphosphinate, di-t-butyl-phenylphosphinate, and diphenyl-phenylphosphinate. , 2-(4-pentyl-phenyl)-phenylphosphinate, di-(2-t-butyl-phenyl)-phenylphosphinic acid vinegar, di-(2-methyl- 3 -pentyl-phenyl)-phenylphosphinate, di-(2-methyl-4-isooctyl-phenyl)-phenylphosphinate, di-(3-butyl- 4-a-methyl) Phenyl-phenyl)-phenylphosphinate, di-(3-hexyl-4-ethyl-phenyl)-phenyl sulfite vinegar, di-(2,4,6-trimethylphenyl) a monophenylphosphinate, di-(2,3-dimethyl-4-ethyl-phenyl)phenylphosphonate, di-(2,6-diethyl- 3 butyl Phenylphenyl)-phenylphosphinate, di-(2,3-dipropyl-5-butylphenyl)-phenylphosphinate, di-(2,4,6-tri-t — butylphenyl)-phenylphosphinate, bis(2,4-di-t-butyl-5-methylphenyl)biphenyl-4-ylphosphonite Bis(2,4-di-t-butyl-5-methylphenyl)- 4'-(bis(2,41-2 di-butyl-5-methylphenoxy) quinone) biphenyl —4-one-one scaly vinegar, bismuth (2,4-di-t-one-32-200906942 butyl-phenyl)- 4,4'-biphenylene diphosphonite, hydrazine 2,5-di-t-t-butyl-phenyl)- 4,4'-biphenylene diphosphinate, hydrazine (3,5-di-t-butyl-phenyl)-4 4'-biphenylene diphosphinate, bismuth (2,3,4-trimethylphenyl)-4,4'-biphenylene quinone vinegar, bismuth (2,3 —monomethyl-5-ethyl-phenyl)-4,4′-biphenylene diphosphonite, hydrazine (2,3-dimethyl-1,4-propylphenyl)-4, 4'-biphenylene diphosphite, bismuth (2,3-dimethyl-5-t-butylphenyl)- 4,4'-biphenylene diphosphinate, Bismuth (2,5-dimethyl- 4 -t-butylphenyl)- 4,4'-biphenylene diphosphinate, bismuth (2,3-diethyl-5-methyl Phenyl)-4,4'-biphenylene diphosphinate, bismuth (2,6 Diethyl-4-methylphenyl)-4,4'-biphenylene diphosphinate, bismuth (2,4,5-triethylphenyl)-4,4'-Asialian Phenyl diphosphonite, bismuth (2,6-diethyl-4-cyclopropyl)-4,4'-biphenylene diphosphinate, bismuth (2,5-di Ethyl- 6-butylphenyl)- 4,4'-biphenylene diphosphinate, bismuth (2,3-diethyl-5-t-butylphenyl)-4,4 '-Linkene phenyl di- arsenic acid vinegar, hydrazine (2,5 - _ethyl-6-t-butylphenyl) - 4,4'-biphenylene diphosphonite, hydrazine (2,3-dipropyl-5-methylphenyl)-4,4'-biphenylene diphosphinate, bismuth (2,6-dipropyl-4-methylphenyl) a 4,4'-biphenylene diphosphinate, bismuth (2,6-dipropyl-5-ethylphenyl)- 4,4'-biphenylene diphosphonate , (2,3-dipropyl-6-butylphenyl)-4,4'-biphenylene diphosphonite, bismuth (2,6-dipropyl-5-butylbenzene) Base)—4,4' —biphenylene diphosphinate, bismuth (2,3 -dibutyl-4-methylphenyl-33- 200906942 ) a 4,4'-biphenylene diphosphonite, hydrazine (2,5-dibutyl-3-methylphenyl) —4,4′-biphenylene diphosphinate, bismuth (2,6-dibutyl-4-methylphenyl)-4,4′-biphenylene diphosphinate , 肆 (2,4 - one-t-butyl-3-methylphenyl)- 4,4'-biphenylene-one-nano acid vinegar, bismuth (2,4 one one one t-butyl —-5-methylphenyl)- 4,4'-biphenylene diphosphinate, hydrazine (2,41-2 di-butyl-6-methylphenyl)-4,4 'A biphenylene diphosphite, bismuth (2,5- _-t-butyl-3-methylphenyl)- 4,4'-biphenylene diphosphinate,肆(2,5-di-t-t-butyl-4-methylphenyl)-4,4'-biphenylene diphosphinate, hydrazine (2,5-di-t-butyl- 6-methylphenyl)- 4,4'-biphenylene diphosphinate, bismuth (2,6-di-t-butyl-3-methylphenyl)- 4,4' Biphenylene diphosphite vinegar, bismuth (2,6 — __ —t — butyl 4-methylphenyl) — 4, 4′ — subunitic base — arsenic acid vinegar, hydrazine (2,6-mono-t-butyl-5-methylphenyl) a 4,4 '-biphenylene dibasic acid ester, bismuth (2,3-dibutyl-4-ethylphenyl)- 4,4'-biphenylene diphosphonite , 2,4, di-butyl-3-ethylphenyl)-4,4'-biphenylene diphosphinate, bismuth (2,5-dibutyl-4-ethylbenzene) a 4,4'-biphenylene- ary acid vinegar, bismuth (2,4 - ___t - butyl-3-ethylphenyl)- 4,4'-biphenylene diam Phosphonate, bismuth (2,4-di-t-butyl-5-ethylphenyl)- 4,4'-biphenylene diphosphinate, bismuth (2,4-—one _ t — butyl-6-ethylphenyl)-4,4′-biphenylene diphosphinate, hydrazine (2,5-di-t-butyl-3-ethylphenyl)— 4,4'-biphenylene diphosphinate, bismuth (2,5-di-t-butyl-butyl- 4-34-200906942 monoethylphenyl)-4,4,-biphenylene Diphosphonate, bismuth (2,5 one two one T-butyl-6-ethylphenyl)-4,4'-biphenylene diphosphinate, hydrazine (2,6-di-t-butyl-3-ethylphenyl)- 4,4, a biphenylene diphosphinate, bismuth (2,6-di-t-butyl-4-ethylphenyl)- 4,4'-biphenylene diphosphonium Acid ester, hydrazine (2,6-di-t-butyl-5-ethylphenyl)- 4,4'-biphenylene diphosphinate, hydrazine (2,3,4-tributyl) Phenyl)-4,4,-biphenylene diphosphinate, bismuth (2,4,6-tri-t-butylphenyl)-4,4,_biphenylene di- Phosphonate and the like. The phosphorus-based compound of the above type can be obtained, for example, from the trade name "IRGAFOS P-EPQ of Ciba Specialty Chemicals Co., Ltd., "GSY-P 101" by Suga Chemical Industry Co., Ltd.) as useful in the present invention. The phosphorus compound is preferably a phosphinic acid phthalate compound, such as ruthenium (2,4-di-t-butyl-phenyl)- 4,4,-biphenylene diphosphinate, etc. 4,4 , a biphenylene di-phosphinate compound is preferably 'excellently ruthenium (2,4-di-t-butyl-5-methylphenyl)-4,4'-biphenylene Di-phosphonite. (A large-radical radical scavenger) The "alkyl radical scavenger" of the present invention is capable of imparting a radical reaction capable of reacting rapidly with a radical of a home base, and is carried out with a radical radical. A compound which does not cause a stable product of the subsequent reaction after the reaction. Preferred examples of the alkyl radical scavenger in the present invention include the compound represented by the general formula (1) and the compound represented by the above formula (2)-35-200906942. Specific examples of the compound represented by the general formula (1) are described, and the present invention is not limited thereto. In the above general formula (1), R! represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, particularly preferably a hydrogen atom or a methyl group. R2 and R3 each independently represent an alkyl group having 1 to 8 carbon atoms, and may be linear or may have a branched structure or a cyclic structure. R2 and R3 are preferably a structure represented by "*-C(CH3)2-R'" containing a carbon of 4 grades (* is represented by a linking moiety of the aromatic ring, and R' is an alkyl group having 1 to 5 carbon atoms). R2 is preferably tert-butyl or tert-pentyl. R3 is preferably tert-butyl, tert-pentyl or tert-octyl. As a compound represented by the above general formula (1), "Sumi 1 izer G Μ,", "S umi 1 izer GS," is commercially available from Sumitomo Chemical Co., Ltd., and the general formula (1) is given below. Specific examples of the compound shown are not limited thereto. -36- 200906942 [化3]

{CH?)&gt;-CH=CH-(CH2)7CH3 卿Λ -37- 200906942 mi (1)-4

CHg CHa

qcH?h H3C-c-CH3 HaG-C-CH^(CH2)2GH3 {CHi)2CH3 (1)-6 OH (HsChC, ^i^ a CH2

〇 o-g-ch=ch2CIGH3)3

H3C-C-CH3 H3C-C-CH3 (CH2)4eH3 &lt;ch2)4ch3 (1)-7 OH 0-C-GH=CH2 ΐγί eHa γί ch3 ch3 -38- 200906942 [Chemical 5]

Ch2ch3 h3c oh H3G-CH2

(H3C) 3C.

H3C-C-CH3 HaC-d-CHa (CH2)2CH3 (qH2)2CH3 0-d-eH=0H2, C(CHa)s 0~G-CH=CH2 C&lt;CH3)s 9-G-GH-CH2 CHi CHi-Cfiz ch3 pC-CH-CHj C(CHs)3 (1)-12

(HiChC

CH=CH2 C(〇H3k H3C-C-GH3 HiC-Jianyi C:H3 _4CH3 (ch2)4ch3 -39- 200906942 [1]-13 H3GH2C{H3G)i&lt;; (11-14 H4CH2C( H3C)2C ("-1S HaCHiqHjC^p, (1)-16 HaCH2e(H3C)20

CH=CH2 .CfCB^CHsCHa C^-CH^G^ C(CH3)2CH2CH3 H3C-CH3 HSC-,—CHy 0-C-CH=CH2 C_iCH Miscellaneous O^C-CH=CH2 C(C%)2GH2CH3 ( 1)-17

Ch2 ch2 I * 2 CHa CHa O H3CH2C(H3C)2C

C(CH3)2CH2CH3 HiC-^-CHj H3C^G-CH3 Qing tear (CH class 3 (1 卜 18 〇 OH 〇-C-CH=CH2 HsCH2C(H3C)2C ^CtCHs^CHjCH, one c-ch=ch2

HsG-iC-CHi HaC-C-CHa (CH^CHa (CHJiGHj Next, a specific example of the compound represented by the above general formula (2) used in the present invention will be described, but the present invention is not limited thereto. In 2), R12 to Ri5 each independently represent a hydrogen atom or a substituent. Min 12 and R13, 1113 and Rm, or R14 and R15 may be bonded to each other -40 to 200906942, and an integer of 2 to 4 of 1 to 4 is shown. When a ring is formed, r16 represents a hydrogen atom or a substituent, η, Π represents 1, and Ru represents a substituent, and η represents a linking group in which Rii represents a valence of 2 to 4. When R12 to Rl5 represent a substituent, the substituent is used. There is no particular limitation 'for example, a hospital base (for example, methyl, ethyl, propyl, isopropyl, t-butyl 'pentyl, octyl, lauryl, trifluoromethyl, etc.), cycloalkyl group (eg, cyclopentyl, cyclohexyl, etc.), aryl (eg, phenyl, naphthyl, etc.), guanylamino (eg, acetamido, benzylamino, etc.), alkylthio (eg, , methylthio, ethylthio, etc.), arylthio (eg, phenylthio, naphthylthio, etc.), alkenyl (eg, vinyl, 2- Propylene group '3-butenyl group, fluorenyl-methacryl group, 3-pentenyl group, 1-methyl-3-butenyl group, 4-hexenyl group, cyclohexenyl group, etc.), halogen atom (for example , a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like) an alkynyl group (for example, a propynyl group, etc.), a heterocyclic group (for example, 'pyridyl group, thiazolyl group, oxazolyl group, imidazolyl group, etc.), an alkyl sulfonium group a group (for example, methylsulfonyl, ethylsulfonyl, etc.), an arylsulfonyl group (for example, phenylsulfonyl, naphthylsulfonyl, etc.), an alkylsulfinyl group (for example, A) a sulfinyl group, an arylsulfinyl group (for example, 'phenyl sulfinyl group, etc.), a phosphinium group, a fluorenyl group (for example, an ethyl sulfonyl group, a trimethyl acetamyl group, a benzamidine group, etc.) Aminomethyl sulfhydryl (for example, aminocarbonyl, methylaminocarbonyl, dimethylaminocarbonylbutyryl), cyclohexylamine, anilino, oxalylaminocarbonyl Et.), amidoxime (for example, aminosulfonyl, methylaminosulfonic acid, dimethylaminosulfonyl, butylaminosulfonyl, hexylaminosulfonyl, cyclohexylsulfonyl) Mercapto, octylamine sulfonate Base, lauryl sulfonyl sulfonyl, aniline-41 - 200906942 sulfonyl sulfhydryl, naphthylaminosulfonyl, 2-pyridylaminosulfonyl, etc.), sulfonylamino (eg, methanesulfonylamino, Benzenesulfonylamino group, etc., cyano group, alkoxy group (for example, methoxy group, ethoxy group, propoxy group, etc.), aryloxy group (for example, phenoxy group, naphthyloxy group, etc.), heteroepoxy a base, a pyrenyloxy group, a decyloxy group (for example, an ethoxylated group, a benzhydryloxy group, etc.), a sulfonic acid group, a salt of a sulfonic acid, an aminocarbonyloxy group, an amine group (for example, an amine group, B Amino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, laurylamine group, etc.), anilino group (for example, anilino group, chloroanilino group, toluidine group, anisidine group) , naphthylamino, 2-pyridineamino, etc.), imine, urea (for example, methylureido, ethylureido, pentylureido, cyclohexylureido, octylurea, lauryl urea a group, a phenylureido group, a naphthylureido group, a 2-oxime]: a t-stactylureido group, etc., an alkoxycarbonylamine group (for example, a methoxycarbonylamino group, a phenoxycarbonylamine group, etc.)丨兀兴基象基 (for example, A a aryl group, an ethoxy group, a phenoxy group, etc., a aryloxy group (for example, a phenoxy group, etc.), a heterocyclic thio group, a thiourea group, a carboxyl group, a salt of a carboxylic acid, Each group such as a hydroxyl group, a hydrogenthio group, or a nitro group. Further, these substituents may be further substituted by a substituent. In the above general formula (2), Rl2 to R1S are preferably a hydrogen atom or an alkyl group. In the above general formula (2), 'Ri 6 represents a hydrogen atom or a substituent. The unsubstituted group of R|6 may be the same substituent as shown by R 1 2 to R t 5 . In particular, a hydrogen atom is preferably represented by R16. In the above general formula (2), when n is an integer of 丨~4, R is R, and Rm is a substituent. Examples of the substituent include the same substituents as those shown by Ri2~-42-200906942. When n represents an integer of 2 to 4, Rii represents each of the corresponding 2 to 4 valent linking groups.

When R1 1 represents a 2 to 4 valent linking group, examples of the divalent linking group include a divalent alkylene group which may have a substituent, a divalent extended group which may have a substituent, an oxygen atom, a nitrogen atom, and sulfur. Atom, or a combination of these linkages. Examples of the trivalent linking group include a trivalent stretching group which may have a substituent, a trivalent extended aryl group which may have a substituent, a nitrogen atom, or a combination of these linking groups as a tetravalent linking group. a tetravalent stretching group having a substituent, a tetravalent aryl group which may have a substituent, or a combination of these linking groups. In the above general formula (2), 'η is preferably 1 and R n is substituted or Unsubstituted phenyl is preferred as a substituent, with a carbon number of 1 to! The alkyl group of 8 and the alkoxy group having 1 to 18 carbon atoms are preferred, and the group of 1 to 8 carbon atoms having a carbon number of 1 to 8 is preferred. Hereinafter, specific examples of the compound represented by the above general formula (2) in the present invention are shown, and the present invention is not limited thereto. -43- 200906942 [化7]

Ch3

Ch3

Ch3

Ch3 -44 200906942 [Chemical 8]

45- 200906942 [Chem. 9]

-46 - 200906942 [Chem. 10]

(2)-26

Ch3

-47- 200906942 [Chem. 11]

-48- 200906942 [Chem. 12]

-49- 200906942 [Chem. 13]

-50- 200906942 [化14]

Ri (2)-52 —ch3 —H —e4H9(s) —H (2 卜 53 —C4H$(s) —H —which t} —H (2)-54 —Ws) —H —CsH^y — H (2)-55 -H - CSH sub-H (2)-56 -c*H9(t) -H -CSH"W -H (2)^57 - Can'(5) -H -_(S) H (2)-58 —C4H9(t) —H —(CH2kCp2CeH17(ii)—H (2)-59 —C Qing—H—Tao iCO Lu 8h17〇 — —H (2)-60 —C4H9(t) —H —卿iCQ2(CH 灭C4Hs (8) —H (2)-61 —CnHjjS —H —CH3 —H (2)-62 '~~'^8^7 —H —CHi —H (2)-63 — C&lt;isH33 —H —cH3 —H (2)-64 *C24H49 —H —CHS —H (2)-65 —C4H9(t) —H —ci —H (2)-66 —G4H9W —H —0CH3 — H (2)-67 ~C4H9(t) —H —〇—CaH17(n) —H (2)-68 H5C— —ch3 —HH,C—one ch3—H H3C&quot; 'CH3 h3c,,ch3 (2 )-69 —H —H —OG4H9(n) —H (2)-70 —H —H —OCH3 —H (2)-71 —H —H —gh3 —H 200906942 [Chem. 15]

Greasy «2 r3 B* (2)-72 一Η —H —卿q —H (2)-73 —Η —H —CsHiiW —H (2)-74 一Η—H (2)-75 —C m —H —CHa —H (2)-76 HaG- -C8H„(t) —H (2)-77 h3c— —gh3 —H —c$H19 —H h3c ;eight call (2)-78 h3c— —ch3 —H —C12H2s —H k/CH, H3C′ ch3 (2)-79 h3c— —CH, —H —(CHihCOjOeHiTin) —H k^CH, Ha< ̄ : GHs (2)-80 —H —H H3c— -gh3 —H HaC^CHa (2)-81 —H —d-CeHir(n) —H —H (2)-82 I H —0-C8H17(i) One H —H (2)^83 H-NHCOCiHe (8) - H - H (2) - 84 - H - 〇 - C8H17 (ft) - Cl * - H (2) - 85 - CH % - 0 - CeH „(n) — H — H (2) - 86 —CH, —〇-C8H17(I) —H —Cl {2)-87 —H —〇-CeHi7(n) —H —ei (2)-88 —H—N陶 2 —H —H — 52 200906942 [Chem. 16] mm (2)-89 (2)-90 (2)-91 (2)-92 (2)-93 (2)-94 (2)-95 (2)-96 (2) -97 (2)-93⁄4 (2)-99 (2)-100 (2)-101 (2)-102 (2)-103 (2)-104 (2)-105 (2)-106 (2) -107 (2)-108 (2)-109 (2)-110 (2)-111

-c4h9(1) - H - 〇m) - H _H A Talk - H - H - H - 0 (Crt?) 20CHj - OC2H5 - H - H - H - H - H - Cl - H - H - Cl ~C4H9{t) H-H - H - H - H - ch3 - H - OCH3 - H - H - H - H - H - H ^ - H ^ C8H17(t) - CHi - (CH ^ OH _狮·—_纲—{ghj2〇c〇ch3—CiHsW -C3H7O) —Η—Η

—Cl —Cl —Η —F — CN —CH 3 —GiHs —c〇ch3 —COiPiHsdi) _. heart

Rs H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H —H 53— 200906942 [Chemistry 17 ]

Compound No. r2 Ra R4 Rs (2)-112 —Η —Η —ch2oh —H (2)-113 —Η —Η —οη2οη —H (2)-114 —Η —Η —S02CBH17(i) One H ( 2)-115 —Η —C15H3i(n) —H —H (2)-116 —csh19 —Η A CgH&quot; —H (2)-117 -cf3 —Η —H —H (2)-118 io —Η —Cl —H (2)-119 —Η —Η o —H (2)-120 —Η —C4H9(t) —H —C*H9(t) (2)-121 —Η —Η Η O 一^ f CH3 —H (2)-122 —Η —Η —H —H (2)-123 —Η —C4H9(t) —H —H (2)-124 —Η —ch3 —H —ch3 (2)- 125 —Η —Η —(CH2)2C02C1BH37(n) —H (2)-126 —C4H,(t) —Η —H —c4H9(t) (2)-127 —Η —ch3 —H —H (2 )-128 -ο -Η -H -H (2)-129 -Η an och3 -H -H (2)-130 -Η -OH -H -H (2)-131 -Η -OCOC17H35 -H -H (2)-132 —Η —OH —H (2)-133 —C8H17(t) —H —C8H17(t) —H 54- 200906942 [Chem. 18]

-55- 200906942 [Chem. 19]

-56- 200906942 [Chem. 20]

(Other Antioxidants) Specific examples of other antioxidants include di-lauryl 3,3-thiodipropionate, bis-myristyl 3,3'-thiodipropionate, and di-stearate. 3,3 -thiodipropionate, lauryl stearyl 3,3 - thiodipropionate, pentaerythritol monoterpene - lauryl thio-propionate, 3,9-bis (2-lauryl) Sulfur-based compounds such as thioethyl)-2,4,8,10-tetraoxa-spiro-[5,5]undecane. The sulfur-based compound of the above form is commercially available, for example, from Sumitomo Chemical Industries, Inc. under the trade names "Sumilizer TPL-R" and "Sumilizer TP-D". Moreover, the 3,4-di-57-200906942 monohydrogen-2H-1 benzopyran compound, 3,3'-spiro-di-chroman compound, 1,1 snail-manganese compound, morpholine, thiomorpholine, thiomorpholine oxide, thiomorpholine di-oxide, compound having a piperazine skeleton as a partial structure, and JP-A-3-174450 An oxygen sweeping agent such as a dialkoxybenzene compound described above. Part of the structure of these compounds may be part of the polymer or regularly become a side chain of the polymer. <<Hindered Amine Light Stabilizer>> In the present invention, the deterioration preventing agent at the time of heat fusion of the optical film is further deteriorated by the external light of the backlight which is exposed as a polarizing protective film after manufacture or the backlight of the liquid crystal display. A hindered amine light stabilizer (HALS) compound, which is a known compound, for example, contains the columns of columns 5 to 11 of the specification of U.S. Patent No. 4,691,956 and the specification of U.S. Patent No. 4,83,405. The 2,2,6,6-tetraalkylpiperidine compounds described in the third to fifth columns, or the acid addition salts thereof or the complexes thereof with the metal compounds. Specific examples of the hindered amine light stabilizer include bis(2,2,6,6-tetramethyl-4-piperidine) sebacate and bis(2,2,6,6-tetramethyl). _4 piperidine) succinate, bis(1,2,2,6,6-pentamethyl-tetra-piperidinyl) sebacate, bis(N-octyloxy-2,2,6, 6-tetramethyl-4-piperidine) sebacate, bis(N-benzyloxy 2,2,6,6-tetramethyl-4-piperidine) sebacate, double (N- Cyclohexyloxy 2,2,6,6-tetramethyl- 4 piperidine) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidine)2-( 3,5-di-t-butyl-4-hydroxybenzyl)-2-butylmalonate-58- 200906942, bis(1-propene oxime-2,2,6,6-tetramethyl 4- 4-piperidine) 2,2-bis(3,5-di-t-butyl-4-hydroxyphenylmethyl)-2-butanemalonate, bis(1,2,2,6, 6 —pentamethyl- 4 piperidine) sebacate, 2. 2. 6. 4-tetramethyl-4-piperidine methacrylate, 4-[3 - (3,5-di-t-butyl-4-hydroxyphenyl)propanyloxy]-1 [2 - (3 -(3,5-di-t-butyl-4-hydroxyphenyl)propanyloxy)ethyl]- 2,2,6,6-tetramethylpiperidine, 2-methyl-one 2-(2,2,6,6-tetramethyl-tetra-piperidinyl)amino-N-(2,2,6,6-tetramethyl-4-piperidine)propanamine, hydrazine (2 , 2,6,6-tetramethyl- 4 piperidine) 1,2,3,4-butanetetracarboxylate, hydrazine (1,2,2,6,6-pentamethyl- 4 piperidine ) 1,2,3,4-butanetetracarboxylate, and the like. Further, it may be a polymer compound, and specific examples thereof include N,N',N",N"'--[4,6-bis-[butyl-(N-methyl- 2. 2. 6. 6-tetramethylpiperidine 4-yl)amino]-triazine 2-yl]-4,7-a-azaindole-1,10-diamine, dibutylamine and 1,3,5 - San Xiao Bing &gt; 4'-double (2,2,6,6-tetramethyl-4-piperidine)-1,6-hexamethyldiamine and N- (2,2,6,6 - a polycondensate of tetramethyl- 4 piperidine) butylamine, dibutylamine and 1,3,5-triazine with hydrazine, Ν'-double (2,2,6,6-tetramethyl-4) Polycondensate of piperidine) butylamine, poly[{(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine 2,4 1-2 yl} { (2, 2,6,6-tetramethyl-4-piperidine)imine}hexamethyl{(2,2,6,6-tetramethyl-tetra-piperidinyl)imine}], 1,6 - Hexanediamine-indole, Ν' a pair (2,2,6,6-tetramethyl-4--D-D) and morphine-2,4,6-dichloro- 1,3,5-two Xiaozhi polycondensate, poly[(6-morpholino-s-triazine 2,4-12-diyl) [( -59- 200906942 2. 2. 6. 6-tetramethyl-4-piperidine)imine]~hexamethyl [[2,2,6,6-tetramethyl-4-piperidine)imide]] and other piperidine rings A high molecular weight HALS with a combination of multiple phases; a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, 1,2,3,4 — Tetracarboxylic acid and 1,2,2,6,6-pentamethyl-4-piperidol and 3,9-bis(2-hydroxy-I, !-dimethylethyl)-2,4,M 〇_tetraoxo-spiro-a compound such as a mixed esterified product of [5,5]undecane, which is a compound in which a piperidine ring is bonded via an ester bond, but is not limited thereto. They also use dibutylamine and 1,3,5-triazine with hydrazine, Ν'-double (2. 2. 6. a polycondensate of 6-tetramethyl- 4 piperazine D-butylamine, poly[{(1,3,3,3-tetramethylbutyl)amino-1,3,5-triazine 2,4 —二—基} { (2,2,6,6—tetramethyl- 4-a H-denine)imine}hexa-methyl{(2. 2. 6. Number average of 6-tetramethyl-4-piperidineimine}], dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1 piperidine ethanol It is preferred that the molecular weight (?n) is from 2,000 to 5,000. As the hindered amine compound of the above-mentioned form, for example, "TINUVIN 144" and "TINUVIN 770" available from Ciba Specialty Chemicals Co., Ltd., and "ADK STAB LA-5 2" available from ADEKA, Inc., can be used. In the present invention, the hindered amine light stabilizer is preferably added in an amount of from ο1 to 10% by mass, preferably from 0 2 to 5% by mass, more preferably 0. 5 to 2% by mass. These can be used in combination of two or more types. -60-200906942 "Acid scavenger" The cellulose ester can also be decomposed by an acid in a high-temperature environment by melt film formation. The optical film of the present invention preferably contains an acid scavenger as a deterioration preventing agent. The acid scavenger which is useful in the present invention is a compound which is inert to the acid after the reaction with the acid, and the epoxy group-containing compound described in the specification of U.S. Patent No. 4,137,201 is preferred. The epoxy compound as such an acid scavenger is known in the art field as a diglycidyl ether containing various polyglycols, particularly an epoxy of about 8 to 40 moles per 1 mole of the polyglycol. A metal epoxy compound such as a condensation-derived polyglycol or a glycerol diglycidyl ether (for example, a vinyl chloride polymer composition) and a vinyl chloride polymer composition are used at the same time from the past. ) an epoxidized ether condensation product, a diglycidyl ether of bisphenol A (ie, 4,4'-dihydroxydiphenyldimethylmethane), an epoxidized unsaturated fatty acid ester (especially 2 to 22) An alkyl ester of a carbon atom of 4 to 2 carbon atoms (for example, butyl epoxy stearate), and various epoxidized long-chain fatty acid triglycerides (for example, a ring) The composition of oxidized soybean oil, epoxidized linseed oil, etc., as representative examples of epoxidized vegetable oils and other unsaturated natural oils (sometimes referred to as epoxidized natural glycerides or unsaturated fatty acids, these fatty acids generally contain 12 ~22 carbon atoms). Further, as the commercially available epoxy group-containing epoxide resin compound, EPON 8 15C or other epoxidized ether oligomer condensation product -61 - 200906942 can also be used as an acid scavenger which can be used for the above. 'The organic acid salt of the oxetane compound or the oxazoline compound or the alkaline earth metal or the acetoacetate complex, and the paragraph 68 to the JP-A-5-947-8. In the present invention, the acid scavenger is added to the mass of the cellulose ester of the present invention by adding 0. 1 to 10% by mass is preferred to add 0. 2 to 5 mass% is preferred to add 0. 5 to 2% by mass is more preferable. These can be used in combination of two or more. Further, the acid scavenger may be referred to as an acid scavenger, an acid scavenger, an acid scavenger or the like, and may be used in the present invention. "Metal Inert Agent" The metal inert agent is a compound which is inactivated by a metal ion which acts as a starter or a catalyst in the oxidation reaction, and examples thereof include an oxime compound, a ruthenium oxalate compound, a triazole compound, and the like. For example, N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propanyl]anthracene, 2-hydroxyethyl oxalate diamine, 2 - Hydroxy-N-(1H-1,2,4-triazol-3-yl)benzamide, N-(5-yert-butyl-2-ethoxyphenyl)-Ν'一(2— Ethyl phenyl) oxalic acid amide and the like. In the present invention, the metal inert agent is added to the mass of the cellulose ester of the present invention. 0002~2% by mass is better, add 0. 0005~2 mass% is better, add 0. 001 to 1% by mass is more preferable. These can be used in combination of 2 or more types. -62- 200906942 <<Plasticizer>> In the formation of the optical film by melt casting of the present invention, it is preferred to add at least one type of plasticizer to the optical film. The plasticizer is generally an additive which improves the fragility or imparts a softening effect by being added to a polymer. However, in the present invention, by adding a plasticizer, the mechanical properties of the optical film can be improved, and the tensile strength can be improved. It is preferable to use a material having such an effect as a plasticizer, such as an effect of imparting water absorption resistance and a decrease in water permeability. Examples of the plasticizer to be used in the present invention include a phosphate-based plasticizer and a polyol ester-based plasticizer (a glycol ester-based plasticizer, a glyceride-based plasticizer, a diglyceride-based plasticizer, etc.). A polycarboxylic acid ester type plasticizer, a carbohydrate ester type plasticizer, a polymer plasticizer, or the like. Among them, a polyol ester-based plasticizer and a polycarboxylate-based plasticizer are preferred, and a polyol ester-based plasticizer is preferred. Further, the plasticizer may be a liquid or a solid, and the composition is preferably colorless in principle. The amount of addition may be such that the amount of the cellulose ester associated with the present invention is preferably selected from the range which does not impair the object of the present invention. It is an optical film which is characterized by containing 1 to 25 mass%. When the amount is less than 1% by mass, the planarity improving effect is not obtained, and when it exceeds 25 mass%, the extravasation is likely to occur, so that the stability of the film over time is not preferable. Preferably, it is an optical film containing 3 to 20% by mass of a plasticizer, more preferably an optical film of 5 to 15% by mass. -63-200906942 The following is a description of specific examples of the plasticizer used in the present invention, but the present invention is not limited thereto. In the present invention, the ester-based plasticizer formed from the polyol and the monocarboxylic acid, and the ester-based plasticizer formed from the polyvalent carboxylic acid and the monohydric alcohol have higher affinity with the cellulose ester, so that it is more preferable The ester-based plasticizer composed of an alcohol and a monocarboxylic acid has a higher affinity with a cellulose ester, which is particularly preferable. Further, the polyol ester-based plasticizer is a compound having a complex base group in one molecule and a compound condensed with a monobasic organic acid, and is called a polyol ester-based plasticizer, and a so-called polycarboxylate-based plasticizer The compound is a compound having a complex carboxylic acid group in one molecule, and a compound condensed with a plurality of monohydric alcohols or a phenol is called a polycarboxylate-based plasticizer. Examples of the polyols used as a raw material of the ester-based plasticizer of the present invention include, for example, the following, but the present invention is not limited thereto. Ribool, arabitol, ethylene glycol, glycerin, diglycerin, diethylene glycol, triethylene glycol, tetraethylene glycol, U-propanediol, 1,3 -propanediol 'dipropylene glycol, tripropylene glycol '丨,2-butanediol, 1,3-butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1, 6 —Hexanediol, hexanetriol, galactitol, mannitol, 3-methylpentane-1,3,5-triol, pinacol, sorbitol, trimethylolpropane Hydroxymethylpropane, trimethylolethane, pentaerythritol, dipentaerythritol, xylitol, and the like. In particular, ethylene glycol, glycerin or trimethylolpropane is preferred. Further, examples of preferred organic acids include acetic acid, propionic acid, butyric acid, isobutyric acid, trimethylacetic acid, acrylic acid, methacrylic acid, cyclohexane residual acid, benzoic acid, and anisic acid 3 . 4,5-trimethoxybenzoic acid, -64- 200906942 toluic acid, tert-butyl benzoic acid, naphthoic acid, picolinic acid, etc., but with higher effect of reducing the moisture permeability of cellulose esters The carboxylic acid is preferably formed, for example, by forming an aromatic ester with an aromatic carboxylic acid. The organic acid to be used in the polyol ester may be one type or two or more types. Further, the OH group in the polyol may be esterified or may partially retain the OH group. Specific examples of the glycol ester-based plasticizer which is one of the polyol esters include ethylene glycol alkyl ester plasticizers such as ethylene glycol diacrylate and ethylene glycol dibutylate, and ethylene glycol bicyclic rings. Ethylene glycol cycloalkane plasticizer such as propyl carboxylate 'ethylene glycol bicyclohexacarboxylate, ethylene glycol dibenzoate, ethylene glycol di-tetramethyl benzoate, etc. A diol aryl ester is a plasticizer. These alkylate groups, cycloalkylate groups, polyaryl groups may be the same or different and may be substituted. Further, it may be a mixture of an alkylate group, a cycloalkylate group or a polyaryl group, and these substituents may be bonded to each other by a covalent bond. The ethylene glycol moiety may also be substituted, and the partial structure of the ethylene glycol ester may be a part of the polymer, or may be a side chain regularly, or may be introduced into an additive such as an antioxidant, an acid sweeping agent, or an ultraviolet absorber. One of the molecular structures is a glyceride-based plasticizer of a polyol ester type, and specifically, triacetin, glyceryl tributyrate, glyceryl diacetate caprylate, and glycerol glycerate Triglyceride such as glycerol alkyl ester such as ester, glycerol tricyclopropyl carboxylate or glycerol tricyclohexyl decanoate, glycerol tribenzoate or glycerol 4-methyl orthoformate Tetraethyl phthalate, diglycerin tetrapropyl-65- 200906942 acid ester, diglycerin acrylate trioctanoate, diglycerin tetralaurate, diglyceride, diglycerol tetracyclobutyl carboxylate, diglycerol A diglycerin aryl ester such as a diglycerol cycloalkanate such as a tetracyclopentyl carboxylate, a diglycerin tetrabenzoate or a diglycerin 3-methylbenzoate. These alkylate groups, cycloalkylcarboxylate groups, and polyaryl groups may be the same or different and may be substituted. Further, the alkylate group, the cycloalkylcarboxylate group or the polyaryl group may be mixed, and these substituents may be covalently bonded to each other. Further, the glycerin and the diglycerin moiety may be substituted, and the partial structure of the glyceride or the diglyceride may be a part of the polymer, or may be a side chain regularly, and may be introduced into an antioxidant, an acid sweeping agent, an ultraviolet absorber, or the like. Part of the molecular structure of the additive. Specific examples of the other polyol ester-based plasticizers include the polyol ester-based plasticizers described in paragraphs 3〇 to 33 of JP-A-2003-121823, and pentaerythritol tetrabenzoate. These nodal base groups, cycloalkyl carboxylate groups, polyaryl groups may be the same or different and may be substituted. Further, it may be a mixture of an alkylate group, a cycloalkyl hydroxyacetate group or a polyaryl group, and these substituents may be covalently bonded to each other. Moreover, the 'polysterol moiety can also be substituted, and the partial structure of the polyol can be part of the sputum or regularly become a side chain, and can also be introduced into an additive such as an antioxidant, an acid sweeping agent, or an ultraviolet absorber. Part of the molecular structure. Among the ester-based plasticizers of the above-mentioned polyols and monocarboxylic acids, the alkyl polyterpene alcohols are described as "specifically, the above-mentioned ethylene glycol dibenzoate-66-200906942, glycerol Benzoic acid ester, diglycerin tetrabenzoate, and exemplified compound 16 described in Paragraph 3 1 of JP-A-2000-128. Specific examples of the dicarboxylic acid ester-based plasticizer which is one of the polycarboxylic acid esters include alkyl dicarboxylates such as dilauryl malonate, dioctyl adipate, and dibutyl sebacate. Alkyl dicarboxylic acid cycloalkane type plasticizer such as an acid alkyl ester type plasticizer, dicyclopentyl succinate or dicyclohexyl adipate, diphenyl succinate, di 4-methylphenyl An alkyl dicarboxylic acid aryl ester such as glutarate is a plasticizer, dihexyl-1,4-cyclohexanedicarboxylate, dimercaptobicyclo[2. 2. 1] a cycloalkyl-dicarboxylic acid alkyl ester such as heptane-2,3-dicarboxylate, plasticizer, dicyclohexyl-1,2-cyclobutanedicarboxylate, dicyclopropyl-1,2 a cycloalkyldicarboxylic acid cycloalkane-based plasticizer such as cyclohexyldicarboxylate, diphenyl-1,1-cyclopropyldicarboxylate, di-2-naphthyl-1,4-cyclohexanedicarboxylate Cycloalkyl dicarboxylic acid aryl esters such as acid esters, diethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate 'di 2-ethylhexyl hydrazine An aryl dicarboxylate type plasticizer such as an acid ester, an aryl dicarboxylic acid cycloalkyl ester type plasticizer such as dicyclopropyl phthalate or dicyclohexyl phthalate, or diphenyl phthalate. An aryl dicarboxylic acid aryl ester plasticizer such as bis- 4 monomethyl phthalate, butyl phthalyl butyl glycolate, ethyl phthalic acid ethyl glycolate, etc. A diol-based plasticizer, a citric acid-based plasticizer such as acetyl citrate trimethyl, ethionyltriethyl citrate or ethyl tributyl tributylate. These alkoxy groups, cycloalkoxy groups may be the same or different or may be substituted. These substituents may be further substituted. The alkyl group and the cycloalkyl group may be mixed, and these substituents may be covalently bonded to each other. -67- 200906942 Moreover, the aromatic ring of phthalic acid may be substituted, and may be a polymer such as a dimer, a trimer or a tetramer. Further, the partial structure of the phthalic acid ester may be a part of the polymer or a side chain which is regularly formed as a polymer, or may be introduced into a molecular structure of an additive such as an antioxidant, an acid sweeping agent, or an ultraviolet absorber. Share. Specific examples of the other polycarboxylic acid ester-based plasticizers include mercapto-polycarboxylic acid esters such as trilauryl tricarboxylate and tributyl-mes-butane-1,4-diethyl-carboxylate. Alkylate polycarboxylate ester plasticizer such as acid alkyl ester plasticizer, tricyclohexyl tricarboxylate, tricyclopropyl-2, methoxy-1,2,3-propane tricarboxylate, etc. Alkyl poly(octylate) aryl esters such as phenyl 2-hydroxyl, 2,3-propane tricarboxylate, tetras-methylphenyltetrahydrofuran 2,3,4,5-tetracarboxylic acid ester It is a plasticizer, tetrahexyl-1,2,3,4-cyclotetracarboxylic acid ester, tetrabutyl- 1,2,3,4-cyclopentene tetracarboxylic acid ester, etc. a plasticizer, a cycloalkyl polycarboxylic acid cycloalkyl ester such as tetracyclopropyl-1,2,3,4-cyclotetracarboxylic acid ester or tricyclohexyl-1,3,5-cyclohexyltricarboxylate Plasticizer, cycloalkyl group such as diphenyl-1,3,5-cyclohexyltricarboxylate 'hexa-4-methylphenyl~1,2,3,4,5,6-cyclohexylhexacarboxylate Polyvalent carboxylic acid aryl ester plasticizer, triaryl benzene 1,2,4-tricarboxylate, tetraoctyl benzene 1,2,4,5~ tetradecanoate Alkylate polybasic acid naphthenate, such as an acid alkyl ester type plasticizer, tricyclopentylbenzene 1,3,5-dicarboxylate 'tetracyclohexylbenzene 1,2,3,5-tetracarboxylic acid ester Aryl polybasic decanoic acid ester of plasticizers such as triphenylphenylhydrazine, 3,5-tetracarboxylic acid vinegar, hexamethyl 4-phenylphenylbenzene 1,2,3,4,5,6-hexacarboxylate It is a plasticizer. Some of the alkoxy groups and cycloalkoxy groups may be the same or different and may be substituted with -68-200906942, or a suitable substituent may be further substituted. The alkyl group, the cycloalkyl group or the substituents may be bonded to each other by a covalent bond. Further, the aromatic ring of phthalic acid may be substituted, and it may be a polymer such as a dimer or a tetramer. Further, the phthalate moiety may be a part of the polymer or a side chain which is regularly formed into a polymer, and is introduced into an additive substructure such as an antioxidant, an acid sweeping agent or an ultraviolet absorber. The ester-based plasticizer is preferably an alkyl dicarboxylate of the above-mentioned polyvalent carboxylic acid or a monovalent alcohol, and specific examples thereof include the above-mentioned dioctyl adipate as another plasticizer used in the present invention, and examples thereof include Phosphate plasticizer, carbohydrate ester plasticizer, polymer plasticizer, and the like. Specific examples of the phosphate-based plasticizer include alkyl phosphates such as triethylsulfonyl and tributyl phosphate, tricyclopentyl phosphate, cycloalkyl esters such as cyclic acid esters, triphenyl phosphate, and tricresol. Phosphate phenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphorus trioctyl phosphate, tributyl phosphate, trinaphthyl phosphate, triphenyl) phosphate, ginseng An aryl phosphate such as phenyl phosphate. This group may be the same or different and may be substituted. Further, it may be a mixture of an alkyl group and an aryl group, and the substituents may be bonded to each other by a valence bond. Further, an ethyl bis(dimethyl phosphate), a butyl bis (phosphate), an alkyl bis(dialkyl phosphate), an ethyl bisphosphonate, and a propyl bis (diethyl) -naphthyl phosphate), phenylene bis(dibutyl phosphate), bis(dioctyl phosphate), bis(dioctyl phosphate), etc. , a polymer, a sub-structure, or an agent, an alkyl ester. The ester is a phosphoric acid hexyl phosphorus, a cresyl ester, or a disubstituted cycloalkyldiethyl (diphenyl bis(biphenyl) ) 'Extension-69- 200906942 Phosphate such as phenyl bis(diphenyl-o- vinegar), dinaphthyl bis(di-tolylphosphoryl phosphate), etc., such as aryl bis(di-aryl phosphate). The substituents may be the same or different and may be substituted. Further, they may be a mixture of a fluorenyl group, a cyclic fluorenyl group, a aryl group, or a substituent may be covalently bonded to each other. Moreover, a partial structure of the phosphate ester may be It is a part of the polymer, or a side chain regularly, and can be introduced into an additive such as an antioxidant, an acid sweeping agent, or an ultraviolet absorber. A part of the structure. Among the above compounds, an aryl phosphate or an aryl bis(di-aryl phosphate) is preferred, and a triphenyl phosphate or a phenyl bis(diphenyl phosphate) is preferred. For the carbohydrate hydrate-based plasticizer, the carbohydrate is a monosaccharide, a disaccharide or a trisaccharide in the form of a sucrose or a sucrose (6-membered ring or a 5-membered ring). Non-limiting examples of the compound include glucose, sucrose, lactose, cellobiose, mannose, xylose, ribose, galactose, arabinose, fructose, sorbose, ribose, and raffinose. The ester is an aliphatic carboxylic acid ester or an aromatic carboxylic acid ester which is a carbonic acid carboxylic acid ester and a carboxylic acid which is dehydrated and condensed to form an ester compound. Examples of the aliphatic carboxylic acid include acetic acid. Examples of the aromatic carboxylic acid, such as benzoic acid, toluic acid, and anisic acid, such as propionic acid, etc. Carbohydrates have a hydroxyl group number depending on the type thereof, and a part of the hydroxyl group can be reacted with a carboxylic acid. The ester compound or all of the hydroxyl groups are reacted with a carboxylic acid to form an ester compound. -70- 200906942 In the present invention, all of the hydroxyl groups are reacted with a carboxylic acid to form an ester compound, which is preferably a carbamate ester-based plasticizer, and specifically, Glucose pentaacrylate, glucose pentapropionate, glucose pentabutyrate, sucrose octaacrylate, sucrose octabenzoate, etc., among which sucrose octaacrylate, sucrose octabenzoate is preferred, sucrose octadecene The acid ester is particularly preferred. The above-mentioned type of carbohydrate ester-based plasticizer can be, for example, a trade name of "Monobit SB" and "Monobit SOA" commercially available from First Industrial Pharmaceutical Co., Ltd. as a polymer plasticizer. Specific examples thereof include an aliphatic hydrocarbon polymer, an alicyclic hydrocarbon polymer, a polyethyl acrylate, a polymethyl methacrylate, a copolymer of methyl methacrylate and 2-hydroxyethyl methacrylate. Vinyl polymer such as methyl methacrylate and a copolymer of methyl acrylate and 2-hydroxyethyl methacrylate, vinyl polymerization such as polyethylene isobutyl ether or poly N-vinyl pyrrolidone Polystyrene, polystyrene, polystyrene styrene, polybutylene succinate, polyethylene terephthalate, polyethylene naphthalate, polyester, polyethylene oxide, polypropylene Polyether such as oxide, polyamine, polyurethane, polyurea, and the like. The number average molecular weight is preferably from 1,000 to 500,000, particularly preferably from 5,000 to 200,000. When it is less than 1,000, the volatility causes a problem, and when it exceeds 500,000, the plasticization ability is lowered, which adversely affects the mechanical properties of the optical film. These polymer plasticizers may be a single polymer of one repeating unit or a copolymer having a plurality of repeating structures. Further, two or more kinds of the above polymers may be used in combination. The optical film of the present invention contains an ester-based plasticizer of a polyhydric alcohol and a monocarboxylic acid, and an ester-based plasticizer of a polyvalent carboxylic acid and a monohydric alcohol, and is 1 to 25% by mass. Good, but you can use a plasticizer other than this. In the optical film of the present invention, an ester-based plasticizer composed of a polyhydric alcohol and a monocarboxylic acid is a phase of an ester-based plasticizer which is better than a trihydric or higher alcohol and a monocarboxylic acid. It has high solubility and can be added as a special feature at a high addition rate, so that it does not cause extravasation even if other plasticizers or additives are used in combination, and it is easy to use it with other kinds of plasticizers or additives as necessary. <<Ultraviolet Absorber>> In the present invention, when the optical film further contains an ultraviolet absorber, the durability can be improved. The ultraviolet absorber is excellent in the absorption energy of ultraviolet rays having a wavelength of 370 nm or less from the viewpoint of preventing deterioration of ultraviolet rays by a polarizer or a display device, and is visible light having a wavelength of 400 nm or more from the viewpoint of liquid crystal display. It is better to absorb less. Examples of the ultraviolet absorber used in the present invention include an oxybenzophenone-based compound, a benzotriazole-based compound, a salicylate-based compound, a benzophenone-based compound, and a cyanoacrylate-based compound. Further, a nickel-salt-based compound or a triazine-based compound is preferred, but a benzophenone-based compound or a benzotriazine-based compound or a triazine-based compound having less coloration is preferred. Further, it is possible to use the ultraviolet absorber described in Japanese Patent Publication No. Hei 10-182621, No. 8-337574, JP-A No. Hei 6 - 1 4 8 4 3 0, and JP-A 02 03-1 1 3 3 1 7 The polymer ultraviolet absorber described. Specific examples of the benzotriazole-based ultraviolet absorber include 2 - -72-200906942 (2, monohydroxy-5, monomethylphenyl)benzotriazole, 2 - (2'-hydroxy-3) ,,5,1-2 tert-butylphenyl)benzotriazole, 2-(2,-hydroxy-3'-tert-butyl-5,monomethylphenyl)benzotriazole, 2_ ( 2'-hydroxy- 3',5'-di-tert-butylphenyl)- 5-chlorobenzotriazole, 2-(2,1-hydroxy-3,-(3",4",5", 6"-tetrahydroindenylmethyl) a 5'-methylphenyl)benzotriazole, 2,2-extension methyl bis(4,1,3,3-tetramethylbutyl a 6-(211-benzotriazol-2-yl) fluorene), 2-(2,-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzo Diterpene, 2 - ( 2 - thiol - 3 - tert - butyl - 5 ' _ (2- octyloxycarbonylethyl) phenyl) 5-chlorobenzotriazole, 2 - (2, one Hydroxy- 3'-(1-methyl-1-phenylethyl)-5'-(1,1,3,3,tetramethylbutyl)-phenyl)benzotriazole, 2- ( 211 _Benzene —2 — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — Triazol-2-yl)phenyl]propionate and 2-ethylhexyl-3-(3-tert-butyl-4-yl-amino-5-(5-chloro-2H-benzotriazole-2) A mixture of phenyl] propionate or the like is not limited thereto. Also, as a sales item, TINUVIN (TINUVIN) 326, TINUVIN (TINUVIN) 109, TINUVIN (TINUVIN) 171, TINUVIN (TINUVIN) 900, TINUVIN (TINUVIN) 928, TINUVIN (TINUVIN) 360 (all are Ciba Specialty Chemicals) , LA31 (made by Adeka Co., Ltd.), Sumisorb 250 (manufactured by Sumitomo Chemical Co., Ltd.), and RUV A-100 (manufactured by Otsuka Chemical Co., Ltd.). -73- 200906942 Specific examples of the benzophenone-based compound include 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-monomethoxybenzophenone, and 2-hydroxyl group. It is not limited thereto, such as 4-methoxy-5-sulfobenzophenone or bis(2-methoxy-4-tetrahydroxy-5-benzylidylphenylmethane). In the present invention, the ultraviolet absorber is preferably a benzotriazole compound. In the present invention, the ultraviolet absorber is preferably added in an amount of 〇1 to 10% by mass based on the mass of the cellulose ester of the present invention. 2 to 5 mass% is preferred to add 0. 5 to 3 mass% is more preferable. These can be used in combination of two or more types. Further, the benzotriazole structure or the triazine structure may be a part of the polymer or a side chain which is regularly formed as a polymer, and is introduced into a molecular structure of other additives such as a plasticizer, an antioxidant, an acid sweeping agent, and the like. . The ultraviolet ray absorbing polymer which has been conventionally known is not particularly limited, and examples thereof include a polymer obtained by separately polymerizing RUVA-93 (manufactured by Otsuka Chemical Co., Ltd.) and a polymer copolymerized with RUVA-9 3 and other monomers. . Specifically, PUVA-30M in which RUVA-93 and methyl methacrylate are copolymerized at a ratio of 3:7 (mass ratio), and PUVA_5 copolymerized at a ratio of 5:5 (mass ratio) are mentioned. 〇M and so on. Further, a polymer or the like described in JP-A-2002- 1 1 33 1 7 can be cited. <<Other Additives>> In the present invention, the cellulose vinegar may contain various additives other than the deterioration preventing agent, the plasticizer or the ultraviolet ray inhibitor. For example, an inorganic compound such as a matting agent, a chelating agent, cerium oxide or cerium salt, a dye, a pigment, a fluorescent material, a dichroic dye, a retention controlling agent, a refractive index adjusting agent, and a gas can be used. It passes through an inhibitor, an antibacterial agent, a biodegradability imparting agent, and the like. Further, it is only necessary to have the above functions, and it is also possible to use an additive which is not classified. As a method of containing these additives in a cellulose ester, each material may be directly mixed in the form of a solid or a liquid, heated and melted, and then kneaded into a uniform melt, followed by casting to form an optical film, or in advance. After all the materials are dissolved in a uniform solution using a solvent or the like, the solvent is removed to form a mixture of the additive and the cellulose ester, which is heated and melted and cast to form an optical film. (matting agent) A matting agent can be added to the film of the present invention in order to impart a lubricity or an optical or mechanical function. Examples of the matting agent include fine particles of an inorganic compound or fine particles of an organic compound. The shape of the matting agent may preferably be a spherical shape, a rod shape, a needle shape, a layer shape, a flat shape or the like. Examples of the matting agent include cerium dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, clay, talc, calcined calcium silicate, calcium citrate hydrate, aluminum citrate, magnesium citrate, calcium phosphate, and the like. Inorganic fine particles such as metal oxides, phosphates, citrates, and carbonates or crosslinked polymer fine particles. Among them, cerium oxide can reduce the haze of the film, which is preferable. These fine particles can be surface-treated by organic matter, thereby reducing the haze of the film. -75- 200906942 The surface treatment may preferably be carried out with a halogenated alkane, an alkoxy decane, a hydrazine nitrogen, a decane or the like. The larger the average particle diameter of the fine particles, the larger the smoothness effect, and conversely, the smaller the average particle diameter, the more excellent the transparency. Moreover, the average particle diameter of the primary particles of the microparticles is 0. 01~1. The range of 0#m. The average particle diameter of the primary particles of the preferred fine particles is preferably 5 to 5 Onm, more preferably 7 to 14 nm. These microparticles can form 0 on the surface of the cellulose ester film. 01~l. The 凹凸/zm bump is preferred. Examples of the fine particles of cerium oxide are Japanese AEROSIL (AEROSIL) 200, 200V, 300 'R972, R972V, R974, R202, R812, 0X50, TT600, NAX50, etc., which are manufactured by Japan AERO SIL Co., Ltd. KE-P10, KE-P30, KE-P100, KE-P150, etc., preferably AEROSIL 200V, R972V' NAX50, KE-P30, KE-P100. These fine particles may be used in combination of two or more kinds. When two or more types are used, they can be mixed at any ratio. Fine particles with different average diameter or material, such as AEROSIL 200V and R972V, can be mass ratio of 0. 1: 99. 9~99. 9: 0. 1 range is used. The method of adding these matting agents is preferably carried out by kneading or the like. . Further, as another form, a matting agent previously dispersed in a solvent and a cellulose ester and/or a plasticizer and/or an antioxidant and/or an ultraviolet ray preventive agent are mixed and dispersed, and then the solvent is volatilized or precipitated to obtain a solid matter. When this is used in the production process of the cellulose ester melt, it is preferred to uniformly disperse the matting agent in the cellulose ester. To improve the mechanical, electrical, and optical properties of the film, the above matting agent may be added. -76- 200906942 and adding these fine particles can improve the smoothness of the obtained film, but it will increase the haze after the addition, so the content is preferably 〇. 〇 01 to 5 mass% ’ is preferably 0. 005~1% by mass, preferably 0. 01~0. 5 mass%. And as the film of the present invention, the haze exceeds 1. 0% will affect the optical material, preferably the haze is less than 1 · 0%, and more preferably it is not.  5 %. The haze can be measured in accordance with JIS-K-7136. In the storage or film forming step of the above optical film, a deterioration reaction may be caused by oxygen in the air. At this time, the stabilization effect can be attained when the above additives are used in combination, and the effect of lowering the oxygen concentration in the air can be obtained to achieve the present invention. As a known technique, the use of nitrogen or argon of an inert gas, decompression to a degassing operation under vacuum, and operation in a closed environment can be used, and a method of presenting the above additive in at least one of the above methods can be used. The optical film can suppress deterioration of the material by reducing the probability of contact with oxygen in the air, and is preferred for the purpose of the present invention. <<Optical Film>> Next, the optical film of the present invention will be described in detail. The optical film of the present invention is a functional film used for various display devices such as a liquid crystal display, a plasma display, and an organic EL display, and more specifically, a polarizing plate protective film for a liquid crystal display device, a retardation film, an antireflection film, and a shell. An optical compensation film such as an upward film, a hard coat film, an antiglare film, an antistatic film, and an enlarged viewing angle. In the optical film of the present invention, in addition to the cellulose ester of the present invention, it may comprise -77-200906942 a cellulose ester resin, a cellulose ether resin, or a vinyl resin (also containing polyvinyl acetate) not related to the present invention. Olefin-based resin, olefin-based resin (original spinnylene resin, monocyclic cyclic olefin resin, cyclic co-diene resin, vinyl alicyclic hydrocarbon resin, etc.), polyester Resin (aromatic polyester, aliphatic polyester, or copolymer containing the same), acrylic resin (also including copolymer), polycarbonate resin, polystyrene resin, polyfluorene resin, poly Acrylate resin or the like. The content of the resin other than the cellulose ester is 〇.  1 to 30% by mass is preferred. The optical film of the present invention can be used for a polarizing plate protective film, a retardation film, and an optical compensation film. Especially suitable for polarizing plate protective film. <<Melt Casting Method>> The optical film of the present invention can be produced by melt casting as described above. The solvent used in the solution casting method (for example, methylene chloride or the like) can be classified into a melt extrusion molding method, a pressure molding method, an expansion method, or the like by a molding method of melt casting by heating and melting. Injection molding method, blow molding method, extension molding method, and the like. In order to obtain a polarizing plate protective film excellent in mechanical strength and surface precision, it is preferable to use a melt extrusion molding method. The optical film is required to have little or no volatile component in the melting and film forming steps. This is foaming when heated and melted, which can reduce or avoid defects in the inside of the film or planarity deterioration of the surface of the film. The content of the volatile component when the optical film is melted is 1% by mass or less, preferably 〇_5% by mass or less, more preferably 0. 2% by mass or less, especially good -78-200906942 is 0. 1% by mass or less. In the present invention, the amount of heat loss corresponding to the temperature of the molten stream is determined by using a differential thermogravimetric measuring apparatus (TG/DTA200 manufactured by SEIKO Electric Co., Ltd.), and this amount is used as the content of the volatile component. The optical film to be used preferably contains the above-mentioned moisture or the above-mentioned volatile component, and is preferably removed before or during heating. As the removal method, a known drying method can be applied, and a heating method, a method, a heating and decompression method, or the like can be carried out, and it can be carried out in the air or in an atmosphere of an inert gas of nitrogen. When these known drying methods are carried out, the quality of the film is better when it is carried out in a temperature region where the film is not decomposed. When drying is carried out before the film formation, the generation of the volatile component can be reduced, and the polyester ester alone or the cellulose ester and the film forming material are divided into at least one kind of mixture or a mixture other than the cellulose ester, followed by drying. The temperature is preferably 70 ° C or more. When there is a material having a glass transition temperature in the dried material, when the glass is heated at a drying temperature where the glass transition temperature is high, the material is difficult to handle. Therefore, when the drying temperature is below the glass transition temperature, when the plurality of materials have a glass transition temperature, , based on the glass transition temperature of the glass transition temperature. It is preferably 70. (: Above, (glass temperature - 5 ° ° C or less), more preferably 丨丨 0 ° C or more, (glass transfer temperature ^ ) ° C or less. Drying time is preferably 〇 5 to 2 4 hours, more preferably 1 ~1 8 is best for 1 .  5 to 1 2 hours. If the drying temperature is too low, the volatile component is delayed, etc., and the pressure is selected. The fiber is dried and the ratio is better than the melting. When the lower transfer f -20, the rate of -79-200906942 is removed and the drying time is too long. Further, the drying step can be carried out in two or more stages. For example, the drying step may include a preliminary drying step of storing the material and a pre-drying step performed between ~1 week before the film formation. (Melt extrusion molding method) Hereinafter, a method for producing the cellulose ester film of the present invention will be described by taking a melt extrusion molding method as an example. Fig. 1 is a schematic view showing the overall configuration of a device for producing a cellulose ester film of the present invention, and Fig. 2 is an enlarged view of a portion from a casting die to a cooling roll. 1 and 2, in the method for producing a cellulose ester film of the present invention, after mixing a material such as a cellulose ester resin, the extruder 1 is used, and the casting die 4 is melted and extruded from the casting die 4 to the first cooling roller 5, In addition to the first cooling roll 5, a total of three cooling rolls of the second cooling roll 7 and the third cooling roll 8 are sequentially externally attached, and after cooling and solidifying, the film 10 is formed. After the film 10 which has been peeled off by the peeling roller 9, the both ends of the film are stretched in the width direction by the stretching device 12, and then taken up by the winding device 16. Further, a contact roller 6 for holding the molten film on the surface of the first cooling roll 5 is provided. The contact roller 6 has a surface having elasticity, and a nip is formed between the contact roller 6 and the first cooling roller 5. The contact roller 6 will be described in detail later. -80-200906942 The method for producing the cellulose ester film of the present invention may be carried out under the same conditions as those used for other thermoplastic resins such as polyester. It is preferred that the material is dried beforehand. The water is dried to a ratio of 100 ppm or less, preferably 200 ppm or less, by a vacuum or a vacuum dryer or a dehumidifying hot air dryer. For example, the cellulose ester-based resin which is dried by hot air or vacuum or under reduced pressure is melted at a temperature of 200 to 300 ° C using an extruder 1 and filtered by a blade type filter 2 or the like. foreign matter. When the feed hopper (not shown) is introduced into the extruder 1, it is preferable to prevent oxidative decomposition or the like under vacuum or under reduced pressure or in an inert gas atmosphere. The necessity of filtration in the present invention will be described in detail below. The cellulose ester used in the present invention preferably has a small amount of foreign matter when it is used as an optical film. The bright spot foreign matter is such that two polarizing plates are arranged in an orthogonal direction (orthogonal Nicols), and an optical film is disposed therebetween, wherein one side is illuminated by the light of the light source, and when the optical film is viewed from the other side, the point where the light of the light source leaks is seen. . In this case, it is preferable that the polarizing plate used for the evaluation is a protective film having no bright foreign matter, and it is preferable to use a glass plate for the protection of the polarizer. The light leakage of the light source is, for example, when black is displayed on the liquid crystal display device, and a part of the light is emitted to make it very conspicuous, and it is necessary to avoid the fact that the quality of the liquid crystal display device is greatly reduced. . Generally, the thinner the film thickness, the smaller the number of bright spots per unit area, and the less the content of the cellulose ester contained in the film, the less the foreign matter tends to be brighter. -81 - 200906942 The bright spot is the diameter of the bright spot at 0. 01 mm or more and 200 pieces/cm2 or less are preferable, preferably 1 inch/cm2 or less, and 50 pieces/cm2 or less is more preferable. 30 pieces/cm2 or less are particularly preferable, and 1 () pieces/cm2 or less are preferable. More special, nothing is best. Also for 0. 005~0. The highlights below 01mm are also preferably 200/cm2 or less, preferably 100/cm2 or less, 50/cm2 or less, and 30/cm2 or less, and 10/cm2 or less. Nothing is best. Among them, the following are considered as causes of bright foreign matter. 1.  Foreign matter (metal ions, garbage, etc.) contained in cellulose derived from natural raw materials.  Foreign matter mixed in the production step of cellulose ester (cellulose, metal ions, garbage, etc. which are not vinegar or low in acetification).  Foreign matter (metal ion, garbage, etc.) mixed with the cellulose ester when it is carried into the extruder purchased from the name of the raw material company. In the process of the above-mentioned 1, 2, the late stage of synthesis of the cellulose ester or the process of obtaining a precipitate When the solution is dissolved in a solvent at one time, the effect of removing the foreign matter through the filtration step in the solution state is not sufficient. On the other hand, the case of 3 is almost impossible to avoid. Therefore, a filter must be introduced between the extruder and the casting mold to reduce the bright foreign matter. When the bright foreign matter is removed by melt filtration, 'from the viewpoint of productivity and deterioration of the cellulose ester, of course, it is preferable that the filtration time is shorter. Therefore, it is preferred that the melt viscosity is small. In addition, when a cellulose ester composition such as a mixing deterioration inhibitor or a plasticizer is added by filtration, a removal efficiency of a bright foreign matter is higher, and it is preferable to prevent deterioration of the cellulose ester. . It is also possible to filter those which are suitable for mixing ultraviolet absorbers and other additives. As the filter medium, a fluororesin such as glass fiber, cellulose fiber, filter paper, or tetrafluoroethylene resin can be used, and a ceramics, a metal, or the like can be used. As the absolute overshoot accuracy, it is preferable to use 50 / z m or less, and 30 / m or less is preferable, and the following is preferable, and 5 / / m or less is preferable. These can be used in combination as appropriate. The filter material may be of a surface type or a depth type, but the depth type is less likely to be blocked and is preferred. Only when considering filtration, the viscosity (melt viscosity) of the melt containing cellulose ester is generally 5000 Pa. Below s, preferably 2000 Pa. s below, better for lOOOPa. Below s, especially good for 800Pa. s below. When the melt viscosity is too high, the filtration speed is lowered to cause a decrease in productivity, the residence time is prolonged, the resin is deteriorated, and the resin pressure is increased to cause damage of the filter material, and the like. Further, when an additive such as a plasticizer is not previously mixed, it can be kneaded in the middle of the extruder. It is preferable to make the mixing device such as the static agitator 3 to be evenly added. In the present invention, it is preferred that the cellulose ester and other additives such as a deterioration preventive agent added as necessary are mixed before melting, and it is more preferable to mix the cellulose ester and the additive before heating. -83- 200906942 The mixing can be carried out by a mixer or the like. Further, it can be mixed in the cellulose resin preparation process as described above. When a mixer is used, a general mixer such as a V-type mixer, a conical spiral type mixer, a horizontal cylinder type mixer, a Henschel mixer, or a ribbon type mixer can be used. After the optical film is mixed as described above, the mixture is directly melted by a press machine to form a film, or once the optical film is pelletized, the particles are melted by the extruder 1 to form a film. Further, when the optical film contains a plurality of materials having different melting points, the so-called rice pass semi-melt is produced only at the temperature of the material having a lower melting melting point, and the semi-melt is introduced into the extruder 1 And film making. When the optical film contains a material which is easily thermally decomposed, a method of directly forming a film under the unprocessed particles for the purpose of reducing the number of times of melting, or a method of forming a film such as a semi-melt of Meton as described above is preferred. As the extruder 1, various commercially available extruders can be used, but a melt-kneading extruder is preferred, and a single-axis extruder or a 2-axis extruder can be used. When the optical film constituent material is directly formed into a film without granules, it is necessary to use a two-axis extruder because the appropriate kneading degree is necessary. It is also possible to use a uniaxial extruder or change the spiral shape to Maddock. Types, Unimelt type, D u 1 mage and other mixing type spirals can be moderately kneaded, so they can be used. As the optical film constituent material, when a pellet or a rice pass semi-molten is used, a uniaxial extruder can be used, and a 2-axis extruder can also be used. The cooling step in the extruder 1 and after the extrusion may be replaced by an inert gas such as nitrogen or the pressure may be lowered to reduce the oxygen concentration. The melting temperature of the optical film in the extruder 1 may vary depending on the optical film adhesion - 84 - 200906942 degree or the amount of discharge, the thickness of the sheet to be produced, etc., but generally, for the glass transition temperature Tg of the film, Tg or more, Tg + 1 30 ° C or less, preferably T g + 10 ° C or more, and T g + 1 2 0 °c or less. The temperature at the time of melt extrusion of the present invention is preferably in the range of 200 ° C to 270 ° C. And the range of 230 to 260 ° C is preferred. The melt viscosity at the time of extrusion is generally 10 to 5000 Pa. s, preferably 50~2000Pa. s, preferably 1〇〇~l〇〇〇pa. s, especially good for 300~ 8 00Pa · s. When the melt viscosity is too high, the filtration rate is lowered, the productivity is lowered, the residence time is prolonged, the resin is deteriorated, and the resin pressure is increased to cause damage to the filter material. On the contrary, when the film is too low, film formation property (planarity, streaking) Occurrence, distortion, peeling from the roller, etc.) may deteriorate, and the optical film retention time in the extruder 1 is preferably shorter, within 15 minutes, preferably within 10 minutes, more preferably Within 5 minutes. The residence time is controlled by the type of extrusion machine 1 and the extrusion conditions, but can be shortened by adjusting the material supply amount or L/D, the number of spiral rotations, the depth of the spiral groove, and the like. The spiral shape or the number of rotations of the extruder 1 can be suitably selected by the viscosity or discharge amount of the optical film. The squeezing speed of the extruder 1 of the present invention is from 1/sec to 1 0000/sec, preferably from 5/sec to 1 〇〇〇/sec, more preferably from 10/sec to 1 0 0 /sec. As the extruder 1 used in the present invention, a plastic molding machine can be generally used. The optical film extruded from the extruder 1 is fed to the casting die 4 through the filter 2, static-85-200906942 agitator 3 (but the static agitator 3 is not necessary), and the self-casting die 4 The film is pressed out of the slit. The casting mold 4 is not particularly limited as long as it is used for producing a sheet or a film. Examples of the material of the casting mold 4 include hard chromium, chromium carbide, chromium nitride, titanium carbide, titanium carbonitride, titanium nitride, ultra-steel, ceramics (tungsten carbide, aluminum oxide, chromium oxide). For spraying or plating, as surface processing, it is possible to apply honing using a grinding stone of less than 1 000 pieces, and use a plane cutting of more than 1 000 diamond grinding stones (the direction of the cutting and the flow direction of the resin are Vertical direction), electrolytic honing, electrolytic composite honing, etc. The preferred material of the lip portion of the casting mold 4 is the same as that of the casting mold 4. Moreover, the surface precision of the protrusion is 0. 5S or less is better, 0. Below 2S is preferred. The slit of the casting mold 4 is configured to adjust the interval. This is shown in Figure 3. One of a pair of projections (lips) forming the slit 32 of the casting mold 4 is a flexible projection 33 having a low rigidity and being easily deformed, and the other is a fixing projection 34. Most of the heating bolts 35 are arranged at a certain pitch in the width direction of the casting mold 4, that is, in the longitudinal direction of the slits 3 2 . Each of the heating bolts 35 is provided with a block 36 having a buried electric heater 37 and a cooling medium passage, and each of the heating bolts 35 penetrates each of the blocks 36 in the longitudinal direction. The base of the heating bolt 35 is fixed to the mold body 3 1, and the tip end is engaged with the outer surface of the flexible protrusion 3 3 . When the block 36 is cooled by a general air conditioner, the input force of the buried electric heater 37 is increased or decreased, and the temperature of the block 36 is adjusted, thereby thermally expanding and heating the bolt-86-200906942 3 5 to change the flexibility protrusion 3 3 . Adjust the film thickness. A thickness gauge is disposed at a desired location after the molding, whereby the detected fabric thickness information is placed in the control device, and the thickness information is compared with the set thickness information by the control device. The signal is used to control the power or operating rate of the heating element of the heating bolt. The heating bolts are preferably 20 to 40 cm in length and 7 to 14 mm in diameter. For example, a plurality of plural heating bolts are arranged at a preferred pitch of 2 〇 4 〇 mm. Instead of the heating bolts, it is also possible to arrange the spacers in the axial direction to manually move them back and forth to adjust the spacing of the slots as the main spacing adjustment member. The gap interval adjusted by the spacer adjusting member is generally 2 0 0 to 1 〇 〇 〇 y m, preferably 300 to 800 # m, more preferably 400 to 600/zm. The first to third cooling rolls are made of a seamless steel pipe having a wall thickness of about 20 to 3 mm, and the surface is mirror-finished. A pipe into which the coolant flows is disposed inside, and the pipe is configured to absorb heat from the film on the roll by the coolant flowing therein. In the first to third cooling rolls, the first cooling roll 5 corresponds to the rotary support of the present invention. On the other hand, the contact roller 6 coupled to the first cooling roller 5 has elasticity on its surface, and is deformed along the surface of the first cooling roller 5 by the pressure of the first cooling roller 5, and is interposed between the first roller 5 and the first roller 5. A nip is formed. That is, the contact roller 6 corresponds to the nip rotating body of the present invention. Fig. 4 is a schematic cross-sectional view showing an embodiment of the touch roll 6 (hereinafter referred to as contact roll A). As shown in the figure, the contact roller A is a member in which the elastic roller 42 is disposed inside the flexible metal sleeve 41. The metal sleeve 41 has a thickness of 0. The 3mm stainless steel maker has a flexibility of -87-200906942. If the metal sleeve 41 is too thin, the strength will be insufficient. On the contrary, the elasticity will be insufficient. Thereby, the thickness of the metal sleeve 41 is 0. The 1~5&quot;1»1 type of the drum 42 is provided with a rubber 4 4 which is a roller-shaped metal inner cylinder 43 which is rotatably supported by a bearing. When the contact roller A is pressurized on the first cooling roller 5, the spring 42 is a metal sleeve 41 which is pressurized by the first cooling roller 5, and the metal and the elastic roller 42 are in a similar shape corresponding to the first cooling roller 5. A nip is formed between the first cooling roll and the first cooling roll. Cooling water 45 flows into the space between the elastic rollers 42 inside the metal sleeve 41. Fig. 5 and Fig. 6 show B of another embodiment of the crimping rotor. The contact roller B has flexibility, and the outer cylinder 5 1 made of a seamless stainless steel pipe 4 m m is disposed in a manner similar to the inner side of the outer cylinder 5 1 and the high-rigidity metal inner cylinder 52. Inflow cooling in the space 53 between the outer cylinder 5 1 and the inner cylinder 52: In detail, the contact roller B is 'rotating shafts 5 5 a, 5 5 b at both ends, and the cylinder supporting flanges 56a, 56b' A thin-walled metal outer cylinder 51 is attached to the outer cylinder support flange 56a and the outer peripheral portion. Further, the fluid supply pipe 59 is formed in a fluid discharge hole 58 formed in the flow passage 57 formed by the axial center portion of the one rotation shaft 55 a, and the fluid supply pipe 59 is connected and fixed to the fluid supply pipe 59. The fluid cylinder 60 is disposed on the axial center of the thin-walled gold 5 1 . The inner cylinder support projections may be attached to both ends of the fluid barrel 60. The upper surface of the elastic roller is deformed into a contact roller (the thickness of the heart is 54. The fluid loaded with the outer 56b is returned to the same outer edge 6 1a -88- 200906942, 61b, from these inner cylinders The metal inner cylinder 52 having a wall thickness of about 15 to 20 mm is attached to the outer cylinder support flange 56b between the outer peripheral portion of the support flanges 61a, 61b. The metal inner cylinder 52 and the thin metal outer cylinder Between 5 1 , for example, a flow space 53 for forming a coolant of about 10 mm is formed, and in the metal inner cylinder 52 , a communication flow space 5 3 and an inner cylinder support flange 6 1 a, 6 1 are formed in the vicinity of both end portions. b. The outer passage 6 2 a, 6 2 b of the outflow port 5 2 a, and the inflow port 52b. Further, the outer cylinder 5 1 has flexibility, flexibility, and restorability similar to rubber elasticity. The thin-walled cylinder theory of elastic mechanics can be thinned within the applicable range. The flexibility evaluated by the thin-walled cylinder theory is expressed by the ratio of the wall thickness t/roller radius r, and the smaller the ratio of t/r, the more flexible High. In the contact roller B, t/rS 0. At 03, flexibility is the optimum condition. Generally, the contact rolls used are: roll diameter R = 2 00~500mm C roll radius r=R/2), roll effective width L = 500~1600mm under r/L &lt; l horizontally long shape. As shown in Fig. 6, for example, when the roll diameter: R = 300 mm, the effective width of the roll: L = 1 200 mm, the wall thickness: the optimum range of t is 15 〇χ〇 · 03 = 4 · 5 mm or less, but for When the width of the molten sheet is 1 300 mm, when the average linear pressure is 99 8 N/cm, the rebound ratio is equal to the thickness of the outer cylinder 51 when the thickness of the outer cylinder 51 is 3 mm, and the outer cylinder 51 is The nip width k of the squeezing direction of the chill roll is also about 9 mm, and the nip width of the rubber roll is shown to be close to about 12 mm, and it is known that the nip can be pinched under the same conditions. Further, the amount of deflection in the nip width k is about 0.05 to 0.1 mm. -89- 200906942 Where, as t/r芸0.03, when the roll diameter is generally R=200~500mm, especially in the range of 2 mm S t S 5 mm, sufficient flexibility can be obtained' and by machining The thinning is also easy to implement and becomes a very practical range. When the wall thickness is 2 mm or less, the elastic deformation during processing cannot be processed with high precision. The conversion of 2 mm gt S 5 mm is 0.0088/s S 0.05 for the normal roll diameter, but it is practically proportional to the roll diameter and the wall thickness under the conditions of t/r and 〇_〇3. It is better to get bigger. For example, the roll diameter: R = 2 0 0, t = 2~3mm, roll diameter: R=500, t=4~5mm, the contact light A, B is, by the unillustrated An energizing means provides energy to the first chill roll. The supply capacity of the energizing means is F, and the width w of the film of the nip (the nip) along the direction of the rotation axis of the first cooling roll 5 is set to 9.8 = F / W (linear pressure) is set to 9.8 to 147 N /cm. In the embodiment of the present invention, a nip is formed between the contact rolls A and B and the first cooling roll 5, and the nip is corrected to be flat between the passages of the film. Therefore, when the contact roller is composed of a rigid body and the nip is not formed between the first cooling roller, the thin film is pressed for a long time, and the flatness can be more reliably corrected. That is, if the line pressure is less than 9.8 N/cm, the plastic film line cannot be sufficiently eliminated. On the contrary, if the line pressure is larger than 14 nN/cm, the film does not easily pass through the nip, and the film thickness tends to cause unevenness. -90- 200906942 In addition, when the surface of the contact rolls A and B is made of metal, the surface of the rolls A and B can be smoothly smoothed compared with the case where the surface of the contact roll is rubber, so that a film having high smoothness can be obtained. . Further, as the material of the elastic body 4 4 of the elastic roller 42, an ethylene-propylene propylene rubber, a neoprene rubber, a ruthenium rubber or the like can be used. However, it is important to eliminate the plastic film line by contact with the light 6 and the film viscosity when contacting the film is required to be an appropriate range. Further, it is known that the cellulose ester has a large viscosity change due to temperature. Therefore, in order to set the viscosity when the contact roller 6 is pressed against the optical film to an appropriate range, it is important that the film temperature at which the contact roller 6 sandwiches the optical film must be set to an appropriate range. When the present inventors regard the glass transition temperature of the optical film as Tg, the optical film is pressed against the film temperature T before the contact roller 6 to satisfy the Tg. &lt;T &lt; T g + 1 1 0 °C conditions are preferred. If the temperature T of the optical film is lower than Tg, the film viscosity will be too high to correct the film line. Conversely, if the temperature T of the optical film is higher than Tg + 1 1 0 °c, the surface of the optical film and the roller cannot be uniformly adhered, and the film line cannot be corrected. Preferably Tg+10°C &lt;T2 &lt;Tg+90 ° C, more preferably Tg+20t: &lt; T2 &lt; Tg + 70. (: The temperature of the optical film when the contact roll 6 is pressed with the cellulose ester film is set to an appropriate range, and the melt extruded from the casting die 4 is adjusted by the position P 1 in contact with the first cooling roll 5. The length L of the first cooling roller 5 in the nip of the first cooling roller 5 and the contact roller 6 is -91 - 200906942. In the present month, the second roller 5 and the second roller 6 Preferred materials include carbon steel, stainless steel, _lipid, etc. Further, the surface precision is preferably high, and the surface roughness is 0.3 S or less, preferably 〇〇 ls or less. In the present invention, by casting The portion from the opening (lip) to the first portion of the mold 4 is reduced to 7 kPa or less, and the effect of correcting the plastic film line is preferably increased. Preferably, the pressure is 5 Torr to 7 kPa. The method of maintaining the partial pressure of the opening portion (11p) of the male mold 4 to the first roller 5 at 7 〇 kpa or less is not particularly limited, and the self-casting mold 4 is applied to the periphery of the roller to cover the pressure member, and the pressure is reduced. In this case, the suction device is configured such that the device does not become a place of attachment of the sublimate, and the heater is heated to be heated. In the present invention, if the suction pressure is too small, the sublimate material cannot be effectively attracted, so that it is necessary to have an appropriate suction pressure. In the present invention, the film-like cellulose ester in a molten state from the T mold 4 is used. The resin is conveyed in a dense manner in the order of the first roll (first cooling roll) 5, the second cooling roll 7, and the third cooling roll 8, and is cooled and solidified to obtain an unstretched cellulose ester-based resin film 1 In the embodiment of the present invention shown in Fig. 1, the cooled and solidified unstretched film 10 which is peeled off from the third cooling roll 8 by the peeling roller 9 is passed through a dancer roll (film tension adjusting roll) 1 1 The extension machine 1 2 is introduced, and the film 10 is oriented in the lateral direction (width direction). The molecules in the film are aligned by the stretching. The method of extending the optical film in the width direction can be carried out by a known tenter or the like. It is preferable to carry out the extension direction as the width direction 'and the layer of the polarizing film-92-200906942 in the form of a roll. The retardation axis of the optical film formed by the film when extending in the width direction becomes a wide direction. Transmissive axis of polarizing film It is also a wide direction. The transmission axis of the film is parallel to the slow phase axis of the optical film, and the laminate is incorporated into the liquid crystal display device, thereby improving the display of the liquid crystal display device and obtaining a good viewing angle. The temperature Tg can be controlled by the difference in the type of the optical material and the ratio of the materials constituting the film. When the film is made into a retardation film, the Tg is 12 CTC or more, preferably more. In the liquid crystal display device, the image is in the image forming state. The temperature of the device rises, for example, the temperature rise from the light source causes a change in the temperature of the film. At this time, the temperature of the film is used, and the Tg of the optical film causes the retention of the molecules fixed by the inside of the film.値, and as a film, the size of the shape changes greatly. When the Tg of the optical film is too high, the optical film is too high in temperature and the energy consumption of the heating is increased, and the optically thin material itself is decomposed, and coloring is caused thereby, so that it is preferably 250 ° C or less. . Further, in the extending step, a known heat setting condition and a cooling treatment can be carried out, and the optical film having a desired purpose can be appropriately adjusted. In order to impart the function of the phase difference film of the phase difference film and the phase difference film of the liquid crystal display device, the above extension can be appropriately selected, and the optical polarization thin polarizing plate is compared, and the optical environment of the film 135 〇 C itself is lower. At the time of film formation, the Tg is carried out by the heat-fixing treatment of the Tg, the relaxation characteristic, and the heat-fixing treatment of -93-200906942. In the case where the stretching step and the heat setting treatment are carried out, the stretching step and the heat setting treatment may be appropriately selected. When manufacturing a retardation film as an optical film, and the function of the polarizing film to protect the film, refractive index control must be performed, but the refractive index control can be performed by an extending operation, and an extending operation is preferred. The extension method will be described below. In the step of extending the retardation film, the stretching of the cellulose resin in the direction of 1.0 to 2.0 times in the direction of the film and the stretching in the direction of the film in the direction of the intersection of 1.01 to 2.5 times can control the necessary retention 値R〇 And Rt. Wherein R 〇 represents in-plane enthalpy, and Rt represents 厚度 厚度 in the thickness direction. The retained enthalpys Ro and Rt can be obtained by the following formula. Formula (i) Ro = ( nx-ny) xd Formula (ii) Rt = ( (nx+ny) /2-nz) xd (wherein nx represents the refractive index in the direction of the slow axis of the film, ny represents The refractive index in the direction of the fast axis of the film, nz represents the refractive index in the thickness direction of the film (the refractive index is measured at a wavelength of 590 ° C in an environment of 23 ° C, 55% RH), and d represents the film thickness (nm). The refractive index of the optical film is Abbe's refractometer (4T), the thickness of the film is obtained using a micrometer, and the retention time is 自动 A BRA - 2 1 ADH (manufactured by Oji Scientific Instruments Co., Ltd.) Each measurement was performed. The extension can be carried out, for example, for the long direction of the optical film and in the direction orthogonal to the plane of the optical film, i.e., for the width direction, successively or simultaneously. At this time, if the stretching ratio in at least one direction is too small, a sufficient phase -94 - 200906942 is not obtained, and if it is too large, the stretching becomes difficult and the optical film is broken. For example, when it is extended in the direction of the melt casting, if the shrinkage in the width direction is too large, the crucible will be too large. At this time, it is suppressed that the width of the film is shrunk or extended in the width direction. When extending in the width direction, uneven refractive index distribution occurs in the width direction. This distribution sometimes occurs when the tenter method is used, and it is presumed that when the optical film is stretched in the width direction, a contraction force is generated in the central portion of the optical film, and the end portion is fixed, which is so-called The bowing phenomenon. At this time, when the stretching is also performed in the casting direction, the bowing phenomenon can be suppressed, and the uneven distribution of the phase difference in the width direction can be reduced. By extending in the two-axis directions parallel to each other, the film thickness variation of the obtained optical film can be reduced. When the film thickness of the retardation film is excessively changed, the phase difference is uneven, and when it is used for a liquid crystal display, it may cause unevenness in coloring or the like. The film thickness variation of the optical film is ±3%, more preferably ±1%. In the above object, the method of extending in the two-axis direction orthogonal to each other is effective, and the stretching ratio in the two-axis direction orthogonal to each other is 1.0 to 2.0 times in the final casting direction, and 1.01 to 2.5 times in the width direction. The range is preferably, and it is more preferable to obtain a retention enthalpy which is carried out in the range of 1. 〇 5 to 2.0 times in the width direction in the casting direction of 1. 〇1 to 1. 5 times. When there is an absorption axis of a polarizer in the longitudinal direction, the transmission axes of the polarizers in the width direction can be made uniform. In order to obtain a long-length polarizing plate, the retardation film -95-200906942 is preferably extended in the width direction to obtain a slow phase axis. When a cellulose ester having a positive birefringence is used for the stress, when the above structure is extended in the width direction, the retardation axis of the retardation film can be stressed in the width direction. In this case, in order to improve the display quality, the retardation axis of the retardation film is preferably in the width direction, and the retention of the target must be satisfied, and the formula: (the stretching ratio in the width direction) &gt; (the stretching ratio in the casting direction) condition. After the extension, the end portion of the optical film is cut by the slitting machine 13 as a slit of the width of the product, and then formed by the edge ring 14 and the back side light processing device at the two ends of the film. The knurled processing is performed by the winder 16 to prevent the occurrence of sticking or scratching in the cellulose ester film (yuan roll) F. In the method of burring, a metal ring having a convex and concave pattern on the side can be processed by heating or pressurization. Further, the holding portion of the press plate at both end portions of the film is generally deformed and cannot be used as a film product. Therefore, it can be reused as a raw material after being cut. Continuing the optical film winding step is such that the film is wound on the take-up reel by keeping the shortest distance between the outer peripheral surface of the cylindrical roll film and the outer peripheral surface of the previous transfer roll. Further, before the take-up reel, means such as a static eliminating fan for removing or reducing the surface potential of the film may be provided. The coiler for producing the optical film of the present invention can be used by a general method, and can be wound by a winding method such as a constant tension method, a constant torque method, a tilting tension method, or a program tension control method with a constant internal stress. Further, the initial winding tension at the time of winding the optical film is preferably 9 〇 2 to 300.8 N/m. -96- 200906942 In the method of the present invention, in the winding step of the film, it is preferred to wind up the film under the environmental conditions of a temperature of 20 to 30 ° C and a humidity of 20 to 60% RH. In this way, the temperature and humidity of the optical film winding step can be adjusted to improve the humidity change resistance of the 値 (Rt) in the thickness direction. When the temperature in the winding step is less than 20t, crepe is generated, and the deterioration of the quality of the film roll makes it impossible to use it. When the temperature in the winding step of the optical film exceeds 30 Å, wrinkles are still generated, and the film roll quality is deteriorated, which is not practical. Moreover, if the humidity in the winding step of the optical film is less than 20% RH, it is easy to generate static electricity, and the deterioration of the film roll quality makes it impossible to use it. However, the humidity in the winding step of the optical film exceeds 6〇% RH. At the time, the roll quality, the lamination failure, the conveyability, and the like may deteriorate. When the optical film is wound into a roll shape, it can be any material as the core of the roll, but it is preferably a hollow plastic core, which is resistant to heat treatment as a plastic material. The heat-resistant plasticity of the temperature may be a resin such as a phenol resin, a xylene resin, a melamine resin, a polyester resin or an epoxy resin. Further, it is preferable to use a tempered thermosetting resin such as glass fiber. For example, 'Hollow plastic core · · The outer diameter of 6 inches (hereinafter referred to as 2 · 5 4 c m ) made of FRP, and the inner core of 5 inches. The number of rolls of these cores is preferably 1 or more, more preferably 500 or more, and the thickness of the film is preferably 5 cm or more, and the width of the film substrate is preferably 80 cm or more. Very good. -97- 200906942 The thickness of the optical film of the present invention is preferably from 10 to 500 / zm, particularly preferably less than 20 // m, depending on the optical film to be used. Preferably, the upper limit is 150#m or less. Good, 120/im is better with 25~90#m. When the optical film of the present invention has a retardation film film and the film thickness of the optical film is within the above range, it is preferable for a liquid crystal display of a brain or a portable electronic device. On the other hand, when the optical film is too thin, it is difficult to perform as a phase, and the ability to protect the moisture permeability of the film is lowered, which is not preferable. When the retardation axis or the fast phase axis of the retardation film exists at an angle of Θ 1 in the film direction, 0 1 is -1 to -0 + 0_5. . This 0 1 is defined as the alignment angle, and the measurement of 0 1 can be measured by KOBRA-21 ADH (manufactured by Oji Scientific Instruments Co., Ltd. 6» 1 to obtain brightness, which can suppress or prevent light leakage, and is faithful to color liquid crystal. The retardation film is arranged such that the VA-type film having a wide viewing angle is used as a region in which the fast phase axis of the retardation film is used as a region, and the image quality is improved. For example, when a polarizing plate or an MVA type is used, a pattern can be used. The composition shown in Fig. 7 is different, but it is better. 爵 3 5 &quot; m or more. The lower is better. Special and polarizing plate protection thin is used for the retention of thin-type light-weight film. The polarizer is carried out by the in-plane of the wet film, with a temperature of 1 °, preferably -5. Using automatic birefringence. In the case where the preferred display device of the image is available, the phase difference thinness 0 1 is disposed in -98-200906942 of the above liquid crystal display device. In FIG. 7, 21a, 21b are protective films, 22a, 22b are retardation films, 25a, 25b is a polarizer, 23a and 23b are the slow axis directions of the film, 24a and 24b are the transmission axis directions of the polarizers, 26a and 26b are polarizing plates, 27 is a liquid crystal cell, and 29 is a liquid crystal display device. The retention Ro distribution in the in-plane direction of the optical film is preferably 5% or less, preferably 2% or less, and particularly preferably 1.5% or less. Further, the retention Rt distribution in the thickness direction of the film is preferably adjusted to 10% or less, more preferably 2% or less, and particularly preferably 1.5% or less. In the retardation film, it is preferable that the variation of the distribution of the retained ruthenium is small. When the liquid crystal display device includes the polarizing plate of the retardation film, it is preferable to prevent color unevenness when the variation of the retention distribution is small. The retardation film is adjusted to have a retention enthalpy which is suitable for improving the quality of the liquid crystal cell of the VA form or the TN form, and is particularly suitable for the MVA form when it is divided into the above-described multiple regions as the VA form, and the in-plane retention R is formed. It is 95 nm or less larger than 30 nm, and the thickness direction retention Rt is adjusted to be larger than 70 nm and 400 nm or less. The in-plane retention R〇 is such that two polarizing plates are disposed between the crossed Nicols polarizing plates to arrange liquid crystal cells. For example, when the configuration is as shown in FIG. 7 'when viewed from the normal direction of the display surface, when viewed in the crossed Nicols state, when viewed from the slope of the normal line of the display surface, the polarized plate is crossed. The Cole state produces a deviation, which compensates for the light leakage caused by this. The thickness direction is retained in the TN form or the VA form described above, and particularly in the case where the liquid crystal cell in the V A form is in the black display state, the birefringence of the liquid crystal cell as seen from the oblique -99-200906942 surface can be similarly compensated. As shown in Fig. 7, in the liquid crystal display device, when two polarizing plates are arranged on the upper and lower sides of the liquid crystal cell, 22b in the figure is a distribution in which the thickness is retained, and Rt is satisfied, and the thickness is retained in the Rt. The total 値 is more than 140 nm, and preferably 500 nm or less. At this time, when the surface of 22a and 22b is retained by Ro and the thickness direction is retained by Rt, the productivity of the industrial polarizing plate can be improved. It is particularly preferable that the in-plane retention Ro is greater than 35 nm and is 65 nm or less, and the thickness direction retention Rt is more than 90 nm, and when it is 180 nm or less, it is suitable for the liquid crystal cell of the MVA form as shown in FIG. In the liquid crystal display device, for example, a light-shielding protective film which is sold as a thin film, a TAC film having a thickness of 35 to 85 μm and a thickness of 20 to 60 nm in the thickness direction of 20 to 60 nm is retained in the surface, for example, 22b of FIG. 7 is used. In the case of the position, the polarizing film of the other polarizing plate can be disposed. For example, the phase difference film disposed in the 2 2 a of FIG. 7 can be used, and the internal retention ratio Ro can be larger than 30 nm and 95 nm or less, and the thickness direction is retarded by the Rt ratio. 140nm large and below 400nm. This improves the display quality and is also good from the production side of the film. "Recycling" In the film forming step, the pressed portion of the pressed film at both ends of the cut film is subjected to pulverization treatment or, if necessary, granulation treatment, and can be reused as a raw material for the same type of film or a raw material for a different type of film. . Two-way and use Rt to reduce the thickness of the thin surface -100-200906942 "Functional Layer" When manufacturing the optical film of the present invention, 'Extension Bli and/or P-side electrostatic layer, transparent conductive layer, hard coating A functional layer such as a cloth layer, an antireflection layer, an antifouling layer, a slippery layer, an easy adhesion layer, an antiglare layer, a gas barrier layer, and an optical compensation layer is coated. It is particularly preferable to provide one layer selected from the group consisting of an antistatic layer, a hard coat layer, an antireflection layer, an adhesive layer, an antiglare layer, and an optical compensation layer. At this time, various surface treatments such as corona discharge treatment, plasma treatment, and chemical treatment may be performed as necessary. <<Basification>> The alkalization treatment may be performed by immersing the film in an alkalizing solution (dipping method) or coating an alkalizing solution (coating method). (Alkali solution) The optical film of the present invention is preferably an alkalization solution using an alkali solution having a concentration of 2 mol/L or more as an alkalizing solution. The alkalizing solution is formed of an alkali agent and water, and may contain a surfactant and a compatibilizing agent depending on the case. The concentration of the above alkali solution (the amount of the alkali agent in the alkali solution) must be determined in accordance with the degree of substitution of the thiol group of the cellulose ester. That is, in the cellulose ester, as the carbon number of the fluorenyl group increases, the alkalization efficiency is remarkably lowered. To increase the carbon number of the sulfhydryl group, the alkali concentration must be increased'. However, if the alkali concentration is too high, the stability of the alkali solution is improved. It will be damaged. 'Precipitation may occur under long-term application. It is necessary to match the structure of cellulose ester 'suitably for the 200906942 alkali solution', where the lower alkali concentration is preferred. Further, when the cellulose ester contains an alkali hydrolyzable additive, it is not preferable to decompose it and excessively raise the concentration. Therefore, the alkali solution used in the present invention is preferably 2 mol/L to 4.0 mol/L, and more preferably 2 mol/L to 2.5 mol/L. In the present invention, the alkalization treatment temperature is preferably from 40 ° C to 80 ° C, preferably from 40 ° C to 70 ° C, more preferably from 40 ° C to 65 ° C. The alkalization temperature is only 40 ° C or more, and alkalization of the surface of the cellulose ester is easy, and adhesion to a polarizer is easily obtained, and a polarizing plate having good durability can be easily produced. On the other hand, if the alkalization treatment temperature is too high, the components (plasticizer, etc.) in the vaporized film may be extracted or decomposed, and the film may be excessively swollen, causing problems such as film surface whitening. Examples of other alkaline agents of the present invention include sodium phosphate, potassium, ammonium, sodium phosphate, potassium, ammonium, ammonium carbonate, ammonium hydrogencarbonate, sodium borate, potassium, and ammonium. An inorganic alkaline agent such as sodium hydroxide, potassium, and lithium 'same ammonium. Further, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine can also be used. , triethanolamine, monoisopropanolamine, diisopropanolamine, ethyl imine, ethyl diamine, pyridine, DBU (1,8-diazabicyclo[5,4,0] — 7-undecene), DBN (1,5-diazabicyclo[4,3,0]-5-nonene), tetramethyl hydroxy oxychloride, tetraethylammonium hydroxide, tetra An organic alkaline agent such as propyl ammonium hydroxide, tetrabutyl chlorohydroxide-102-200906942, or triethylbutylammonium hydroxide. These bases may be used in combination of two or more kinds, and a part thereof may be added, for example, by halogenation. Among these, 'the sodium hydroxide and the barium hydroxide are adjusted to adjust the amount to adjust the solvent of the above alkali solution to a water alone solvent, or water and a mixed solvent. Preferred examples of the organic solvent include monoethers of alcohols and alkanols, ketones, guanamines, guanidines, and ethers, and alcohols having a molecular weight of 61 or more. More preferably, the molecular weight is 61 or more. Ethylene glycol, propylene glycol, butylene glycol, pentanediol, hexamethylene ether, glycerin monoethyl ether, cyclohexanediol, cyclohexane didiol, dipropylene glycol, and the like. The organic solvent used in combination with water can be used in a single type or more. (Basification treatment) The optical film of the present invention as described above can be preferably subjected to a step of subjecting the film to an inspecting treatment and a step of exposing the test solution to a film. Thereafter, the step of neutralizing the alkali solution and the step of washing out the medium may be contained. These steps can be carried out at the time of transporting the film, and the immersion in an alkali solution as described in JP-A No. 2,004-203, pp. The method. The agent may be used alone in the form of a salt. The pH of the organic solvent and the diol compound are preferably molecular alcohols, specific diols, glycerol methanol, diethyl benzene or mixed 2 steps of the foregoing test solution, and the liquid is used by a film, such as a special method, or The alkali solution is carried out at -103 to 200906942. The alkalization time is preferably from 30 seconds to 5 minutes, preferably from 1 to 2 minutes. When the alkalization time is too long, the durability of the polarizing plate described later may be adversely affected. <<Polarizing Plate>> When the optical film of the present invention is used as a polarizing plate protective film, the method for producing the polarizing plate is not particularly limited, and it can be produced by a general method. The inner side of the optical film of the present invention is alkalized, and the treated optical film is immersed in at least one surface of the polarizing film formed by stretching in an iodine solution, and it is preferred to use a fully alkalized polyvinyl alcohol aqueous solution for lamination. The optical film of the present invention is also used on the other side, or another polarizing plate may be used to protect the film. For the optical film of the present invention, a polarizing plate protective film used on the other side can be used as a commercially available optical film. For example, as a cellulose ester film to be sold, KC8UX2M, KC4UX, KC5UX, KC4UY, KC8UY, KCI2UR, KC8UCR-3, KC8UCR-4, KC4FR-1, KC8UY-HA, KC8UX-RHA (above is Konicaminolta) System) and so on. Alternatively, it is preferable to use a polarizing plate protective film which is an optical compensation film of an optical heterogeneous layer formed by orienting a liquid crystal compound such as a discotic liquid crystal, a rod-like liquid crystal or a cholesteric liquid crystal. For example, an optical anisotropic layer can be formed by the method described in JP-A-200-979. By using the optical film of the present invention, a polarizing plate having excellent planarity and a stable viewing angle expansion effect can be obtained. -104- 200906942 Or a film of a cyclic olefin resin other than an optical film, a propylene resin, a polyester, a polycarbonate, or the like can be used as a polarizing plate protective film on the other side. In place of the above-mentioned test, the polarization of the component which is mainly composed of a polarizing plate, which is described in the publication of the Japanese Patent Publication No. Hei 6-94915, and the publication of the polarizing plate which is easy to be processed as described in the publication No. 6-1 1 8 2 3 2 The film is a light element that passes only a polarizing surface in a certain direction, and a representative polarizing film that is now known is a polyvinyl alcohol-based polarizing film, which is obtained by dyeing a polyethylene alcohol-based film with iodine. The dyed dichroic dye is obtained. The polarizing film is preferably formed by subjecting a polyvinyl alcohol aqueous solution to film formation, stretching it after one-axis stretching, or dyeing it to perform one-axis stretching, preferably after treatment with a boron compound. The film thickness of the polarizing film is 5 to 40 //m', preferably 5 to 30/zm, and particularly preferably 5 to 20/m. On the surface of the polarizing film, a polarizing plate was formed by laminating the surface of the optical film of the present invention. It is preferably laminated by a water-based adhesive containing a fully alkalized polyvinyl alcohol or the like as a main component. Since the polarizing film extends in the direction of one axis (usually the long direction), when the polarizing plate is placed in a high-temperature and high-humidity environment, the extending direction (usually the long direction) is tightened, and the direction is perpendicular to the extending direction (usually the width direction). )extend. The thinner the film thickness of the polarizing plate protective film, the larger the expansion ratio of the polarizing plate, and the larger the shrinkage amount in the extending direction of the polarizing film. In general, the direction in which the polarizing film extends is bonded to the casting direction (MD direction) of the film for protecting the polarizing plate. Therefore, when the film for protecting the polarizing plate is formed into a film, the expansion ratio in the casting direction is particularly important. The present invention -105-200906942 The optical film has excellent dimensional stability and can be suitably used as such a polarizing plate protective film. That is, the optical film of the present invention does not increase wavy spots by the durability test under the conditions of 60 ° C and 90% RH, and can be provided for durability even if it is a polarizing plate having an optical compensation film on the inner side. Good visibility of no change in viewing angle characteristics after sex test. The polarizing plate is composed of a polarizing film and a protective film for protecting both sides thereof, and a protective film is laminated on the opposite side of the polarizing plate on the opposite side. The protective film and the release film are used for the purpose of protecting the polarizing plate during inspection of the product when the polarizing plate is shipped. At this time, the protective film is bonded for the purpose of protecting the surface of the polarizing plate, and is used to bond the polarizing plate to the reverse surface of the surface of the liquid crystal panel. Further, the release film is used for the purpose of covering the adhesive layer of the liquid crystal panel, and is used for bonding the polarizing plate to the surface of the liquid crystal cell. "Crystal display device" A polarizing plate using a polarizing plate protective film (also including a phase difference film) containing the optical film of the present invention can exhibit higher display quality than a general polarizing plate, especially for a multi-region type. The liquid crystal display device is preferably a multi-region type liquid crystal display device by a birefringence type. The polarizing plate of the present invention can be in the form of MVA (Multi-domein Vertical Alignment), PVA (Patterned Vertical Alignment), CPA ( Continuous Pinwheel Alignment), -106-200906942 OCB (Optical Compensated Bend) format, IPS (In piace Switching) format, etc., are not limited to the configuration of a specific liquid crystal form or a polarizing plate. The liquid crystal display device can be applied as a device for colorization and animation display, and the present invention can improve the display quality, improve the contrast improvement or the resistance of the polarizing plate, and can exhibit the real moving image display without being fatigued. In a liquid crystal display device including at least a retardation film containing a retardation film, a polarizing plate containing the retardation film of the present invention is disposed one on the liquid crystal cell or two on both sides of the liquid crystal cell. At this time, when the phase difference film side of the present invention containing the polarizing plate is used to face the liquid crystal cell of the liquid crystal display device, the display quality can be improved. In Fig. 7, the films of 22a and 22b are liquid crystal cells facing the liquid crystal display device. In such a configuration, the polarizing plate protective film of the optical film of the present invention can compensate for the optical properties of the liquid crystal cell. When the polarizing plate of the present invention is used in a liquid crystal display device, at least one polarizing plate in the polarizing plate of the liquid crystal display device may be used as the polarizing plate of the present invention. By using the polarizing plate of the present invention, the display quality can be improved, and the liquid crystal display device having excellent viewing angle characteristics can be improved. In the polarizing plate of the present invention, a polarizing plate protective film of a cellulose derivative is used as the opposite side of the retardation film from the viewpoint of a polarizer, and a general-purpose TAC film or the like can be used. The polarizer protection film located far from the liquid crystal cell can be configured with other functional layers in order to improve the quality of the display device. For example, 'in order to improve reflection prevention, anti-glare, scratch resistance, adhesion prevention, and brightness enhancement, a known functional layer as a display may be used as a film contained in a constituent or may be bonded to the surface of the polarizing plate of the present invention, but is not limited only. -107- 200906942 Here. In the general retardation film, when the change in R〇 or Rth is small as the retention property, it is desired to obtain stable optical characteristics, and it is required that the variation of Ro or Rth is small. In particular, in a birefringent type liquid crystal display device, these variations are causes of image unevenness. According to the present invention, the long-length retardation film produced by the melt-casting film forming method is composed mainly of a cellulose resin. Therefore, the alkali-based alkalinization of the cellulose resin can be utilized to carry out the alkali treatment step. When the resin constituting the polarizer is polyvinyl alcohol, the fully alkalized polyvinyl alcohol aqueous solution can be bonded to the retardation film of the present invention in the same manner as the polarizing plate protective film in the past. Therefore, the present invention is excellent in application to the polarizing plate processing method in the past, and is particularly excellent in that a long-sized roller polarizing plate can be obtained. The manufacturing effect obtained by the present invention is particularly remarkable in the case of a long roll of 1 〇〇m or more, and the manufacturing effect of the polarizing plate can be obtained when the length is 1500 m, 2500 m, or 5000 m. For example, in the manufacture of a polarizing plate protective film, the length of the roll is 10 to 5 μm, preferably 50 to 450 0 m in consideration of productivity and transportability, and the film width at this time may be selected from the width of the polarizer or may be applied to The width of the manufacturing process. 0.5~4_0m' is preferably a film made of width of 0.6~3.0m, which can be supplied into a polarizing plate after being wound into a roll shape, and is manufactured for a purpose of a film of a multiple width or more and wound up on a roll, and is obtained after being cut. A wide roll, such a roll can be used for polarizing plate processing. The polarizing plate protective film can be coated with a functional layer such as an electrostatic layer, a cured film layer, a slippery layer, an adhesive layer, an antiglare layer, and a barrier layer before and/or after the extension. At this time, various surface treatments such as a corona discharge treatment, a plasma treatment, and a chemical liquid treatment can be carried out as necessary. The composition of the cellulose resin containing the additives such as the above-mentioned plasticizer, ultraviolet absorber, and matting agent is co-extruded, and the optical film having a laminated structure can be obtained. For example, an optical film such as a skin layer/core layer/skin layer can be produced. For example, the matting agent can be placed in a large amount in the skin layer or only in the skin layer. The amount of the plasticizer and the ultraviolet absorber to be placed may be larger in the core layer than in the skin layer, or may be placed only in the core layer. Further, the core layer and the skin layer may be changed by a type of a plasticizer or an ultraviolet absorber. For example, a low-volatility plasticizer and/or a UV absorber may be contained in the skin layer, and a plasticizer excellent in plasticity or ultraviolet absorption may be added to the core layer. Excellent UV absorber. The glass transition temperature of the skin layer and the core layer may be different, and the glass transition temperature of the core layer is preferably lower than the glass transition temperature of the skin layer. At this time, the glass transition temperatures of both the skin and the core were measured, and the average enthalpy calculated by the volume integral ratio was defined as the above-mentioned glass transition temperature Tg. Further, the viscosity of the melt containing the melt-flowing cellulose ester may be different between the skin layer and the core layer, the viscosity of the skin layer, the viscosity of the core layer, or the viscosity of the core layer, and the viscosity of the skin layer. can.

The dimensional stability of the optical film of the present invention is such that when the film size after 24 hours of being placed at 23 ° C, 5 5 % RH -109 - 200906942 is used as a reference, the dimensional change of 80 ° C and 90% RH is less than ± 2.0%, preferably less than 1.0%, more preferably less than 0.5%. When the optical film of the present invention is used as a protective film for a polarizing plate of a retardation film, when the retardation film itself has a variation of the above range or more, the absolute enthalpy and the orientation angle of the retention property of the polarizing plate are different from those of the original setting. In the following, the present invention will be specifically described with reference to the examples, but the embodiment of the present invention is not limited thereto. &lt;Synthesis of Cellulose Ester&gt; (Synthesis of Cellulose Ester 1) 70 g of acetic acid and 40 g of propionic acid were added to 30 g of cellulose (dissolved paper made from Nippon Paper Co., Ltd.), and 30 minutes at 54 ° C. Stir. After cooling the mixture, 8 g of cooled acetic anhydride, 1 〇 丙 g of propionic anhydride, 1 〇 g of sulfuric acid, and esterification were added to the ice bath. In the esterification, the mixture was stirred for 1 minute while being adjusted to not more than 40 °C. Next, after cooling the mixture again, 2 g of cooled acetic anhydride, 25 g of propionic anhydride, and 2 g of barium sulfate were added to the ice bath to carry out esterification. In the esterification, the mixture was stirred for 50 minutes while being adjusted to not exceed 401. -110 - 200906942 After the reaction was completed, a mixture of 30 g of acetic acid and 10 g of water was dropped over 20 minutes to hydrolyze excess anhydrous matter. While maintaining the temperature of the reaction solution at 40 ° C, 90 g of acetic acid and 30 g of water were added and stirred for 1 hour. After adding the mixture to an aqueous solution containing 2 g of magnesium acetate, the mixture was temporarily stirred and filtered, and sufficiently washed until the pH of the washing liquid was neutral, and dried to obtain cellulose ester 1. With respect to the obtained cellulose ester 1, the degree of substitution (X) of the ethyl thiol group, the degree of substitution (Y) of the propyl group, and the sixth place were determined by the method described in the above-mentioned document by the Japanese Patent No. Tezuka. The degree of substitution of the propyl group (Y6) 'where Χ=1·50, Υ=1·40, γ6=〇.45. From this, the total carbon number (2χΧ+3χΥ) is calculated to be 7.20. Further, under the above conditions, a weight average molecular weight of 2 to 5,000 Å was obtained by gel permeation chromatography, and a differential thermogravimetric analyzer was used to measure a 1% mass reduction temperature Td (l. 〇) under air to obtain 278 °. C. (Synthesis of Cellulose Ester 2 to I5) The synthesis of cellulose ester 1 is carried out in the same manner as in the synthesis of cellulose ester oxime, except that the weight of acetic acid, propionic acid, acetic anhydride, and propionic anhydride is changed. The esters are 2~1 5. With respect to the obtained cellulose_H of the present invention, the total carbon number (2χΧ+3χΥ) degree of substitution (γ) of the fluorenyl group, the degree of substitution of the propyl group of the sixth position (Υ6), and the weight average molecular weight (Mw), The 1% mass reduction temperature Td (1.0) is shown in Table 1. -111 - 200906942 (Comparative Synthesis of Cellulose Ester 16) 70 g of acetic acid and 40 g of propionic acid were added to 30 g of cellulose (dissolved pulp made from Nippon Paper Co., Ltd.), and the mixture was stirred at 54 ° C for 30 minutes. After the mixture was cooled, 1 g of acetic anhydride anhydride, 125 g of propionic anhydride, and 1.2 g of sulfuric acid were added to the ice bath and esterified. In the esterification, the side is adjusted to not exceed 40 ° C ' while stirring for 150 minutes. After the completion of the reaction, a mixture of 30 g of acetic acid and 1 g of water was dropped over 20 minutes, and excess anhydride was hydrolyzed. While maintaining the temperature of the reaction solution at 40 ° C, 90 g of acetic acid and 30 g of water were added and stirred for 1 hour. After the mixture was placed in an aqueous solution containing 2 g of magnesium acetate, the mixture was stirred for a while, filtered, and thoroughly washed with water until the pH of the washing liquid was neutral, and then dried to obtain cellulose ester 1. With respect to the obtained cellulose ester 1, the degree of substitution (X) of the ethyl thiol group, the degree of substitution (Y) of the propyl group, and the C of the sixth place were determined by the method described in the above-mentioned Y. Tezuka's literature. The degree of substitution of the thiol group (Y6), where Χ=1·50, Υ=1·40, Υ6=0.53. From this, the total carbon number (2χχ+3χΥ) was calculated to be 7.20. Further, under the above conditions, a weight average molecular weight of 203,000' was obtained by gel permeation chromatography, and a 1% mass reduction temperature Td (1. 〇) under air was measured using a differential thermogravimetric analyzer to obtain 2 7 7 °. C. (Comparison of the synthesis of cellulose esters 17 to 26) wherein the cellulose esters 17 to 21, 23, 25, and 26 were compared for the synthesis of the cellulose ester 16, and the amounts of acetic acid, propionic acid, acetic anhydride, and propionic anhydride were changed. Synthesis was carried out in the same manner as in the case of cellulose ester 16 under the same synthesis operation as -112-200906942. On the other hand, comparing cellulose esters 22 and 24 with respect to the synthesis of cellulose ester 1, the combination of acetic acid, butyric acid, acetic anhydride, and butyric anhydride was used, and the same amount as cellulose ester 1 was used except that the amount of use was changed. Synthetic operations and synthesis. For each of the comparative cellulose esters 16 to 26 obtained, the total carbon number (2 χΧ + 3xY' or 2 χΧ + 4 χΖ (the degree of substitution of Ζ 醯 ))), the degree of substitution of propyl fluorenyl (Υ), the 醯 第 第The substitution degree of the base (γ6), the degree of substitution of the butyl group (Ζ), the degree of substitution of the butyl group at the 6th position (Ζ6), and the weight average molecular weight (Mw), and the temperature of the 1% mass reduction temperature Td (10) are shown in Table 1. Shown. -113 - 200906942 [i

The present invention The present invention The present invention The present invention The present invention The present invention The present invention The present invention The present invention The present invention The present invention compares comparatively comparatively comparatively comparatively comparatively comparative Td (1.0) (° C) 278 282 277 280 281 283 280 285 305 297 268 292 279 275 T— 00 CN 277 T- 00 CM 280 290 281 280 283 00 CNJ 282 275 I Mw ! 205000 I 224000 217000 ! 198000 220000 I 223000 201000 l__ one | 200000 I 195000 I 206000 186000 | 176000 I 234000 :218000 220000 203000 j 193000 208000 179000 I 220000 213000 192000 200000 ί 222000 213000 211000 Cellulose ester substitution degree CD S' &gt;-N mu Light 嵩mm mm rwgs Zhaogui CO CO 濉City&gt;w«· 0.45 0.40 0.41 0.30 0.42 0.39 0.35 0.45 0.43 0.37 0.42 0.50 0.42 0.40 0.41 0.53 0.48 0.50 0.61 0.36 0.28 (0.44) 0.58 (0.38) 0.40 0.33 &gt;-N mu mm E h 1.40 1.32 1.31 1.10 1.31 1.23 1.26 1.30 1.23 1.26 1.20 1.40 1.50 T— 1.32 1.40 1.60 2.00 1.40 0.80 1.20 (123) 1.30 (0.97) 1.40 1.00 Total carbon number 2x X + 3 x Υ (2χ +4χΖ) 7.20 | 7.05 丨6.63 6.90 I__I i_679_ ! 6.48 6.90 I 6.30 __ ! 6.36 | 6.60 , 7.50 ! 7.00 ! 6.78 | 7.20 ; 7.20 丨7.60 6.60 j 6.40 I __ (7.02) I 6.90 (7.10) 6.20 6.60 Cellulose Ester No. T—(N CO 寸 LO CO N- 00 σ> 〇τ—r— τ—CO \r&gt; CD 卜 CO Gi x — CM CO CN-114 200906942 Example 1 [With cellulose ester Production of Optical Film 1-1] The optical film of the present invention was prepared by melt casting using the above-mentioned synthesized cellulose ester and various additives as follows: 1 - 1 ° cellulose ester 1 100 parts by mass of plasticizer - A 8 Parts by mass IRGANOX1010 (manufactured by Ciba Specialty Chemicals Co., Ltd.) 〇· 5 parts by mass of GSY-P101 (manufactured by Sigma Chemical Industry Co., Ltd.) 0.25 parts by mass

Sumilizer GS (manufactured by Sumitomo Chemical Co., Ltd.) 0.25 parts by mass of TINUVIN 92 8 (manufactured by Ciba Specialty Chemicals Co., Ltd.) 1 · 5 parts by mass After drying the cellulose ester 1 at 13 ° C for 4 hours under reduced pressure and cooling to room temperature, Mixing additives. The above mixture was melt-mixed at 23 ° C using a 2-axis extruder to prepare pellets 1-1. Further, the glass had a glass transition temperature Tg of 1 35t. The pellet 1-1 was melted at 250 ° C under a nitrogen atmosphere, and the extruder 1 passed through the filter 2 and then 'self-casting mold 4 was pressed out onto the first cooling roller 5'. The film is formed by rolling a film between the cooling roll 5 and the contact roll 6. In addition, the hopper opening of the middle part of the extruder 1 is added as a lubricant to the cerium oxide particle AerosilNAX50 (manufactured by Sakamoto Aerosil Co., Ltd.), 0.2 parts by mass, and KE-P100 (manufactured by Nippon Shokubai Co., Ltd.) 〇.〇 2 parts by mass - 115 - 200906942 The interval width of the heating bolt to the casting mold 4 is adjusted to be 0.5 mm from the end portion of the film width direction within 30 mm, and the others are 1 mm. As the contact roller, the contact roller A was used, and the inside thereof was poured into cooling water of 80 °C. The position P1 from the position P1 where the resin extruded from the casting die 4 is in contact with the first cooling roll 5 to the upstream end position P2 in the rotational direction of the first cooling roll 5 which is in contact with the nip of the first cooling roll 5 (nip) The length L of the circumferential surface of the first cooling drum 5 is set to 20 mm. Thereafter, the contact roller 6 is peeled off from the first cooling roller 5, and the melting portion temperature T before the nip of the first cooling roller 5 and the contact roller 6 is measured is measured. In the present embodiment, the temperature T of the melting portion before the nip of the first cooling roller 5 and the contact roller 6 is nip can be raised by 1 mm above the upstream end P2 of the nip. The set thermometer (HA-2〇〇E, manufactured by Anritsu Co., Ltd.) was measured. As a result of the measurement in this example, the temperature T was 141 °C. The contact roller 6 was introduced into the tenter at a line pressure of 14.7 N/cm ° for the first cooling roll 5, and was stretched 1.3 times in the width direction at 160 t, and then cooled to 30 t in the width direction while being tempered by 3 %. After that, the self-pressing plate is opened, and the pressing plate holding portion is cut at a width of 10 mm and a height of 5/zm at both ends of the film to a mark processing. The winding tension is 22〇N/m′, and the core is rolled at a taper degree of 40%. Rolling. Further, the optical film was adjusted to have an extrusion amount and a drawing speed to a thickness of 80 /zm, and the finished optical film was 143 mm wide and wound up. The core of the core -116- 200906942 inch is 152mm inner diameter, outer diameter 165~180mm' length 1550mm. As the core material, a pre-stained resin in which an epoxy resin is immersed in glass fibers or carbon fibers is used. An epoxy-based conductive resin was coated on the surface of the core, and the surface was honed to have a surface roughness Ra of 〇.3//m. Moreover, the roll length is 25 0 0 m. A part of the optical film was cut out from the original film sample of the present invention, and this was taken as the optical film 1-1 of the present invention. [Production of Optical Films 1-2 to 1-26] In the production of the optical film 1-1, the particles of the present invention were similarly produced by changing the type of the cellulose ester as shown in Table 1. 5. Compare the particles 1-1 6~1-26. Further, the optical films 1-2 to 1-15 of the present invention and the comparative optical films 1-16 to 1-26 were produced in the same manner as described above. Further, the amount of the cellulose ester added in place of the cellulose ester 1 used was the same as that of the cellulose ester 1. The structures of the plasticizer-in, 1110 八1 0 and 1010, 〇3丫-P101, Sumilizer GS, and TINUVIN 928 used in Example 1 were as follows. Further, cellulose esters 1 to 21, 23, 25, and 26 are cellulose acetate propionates, and cellulose esters 22 and 24 are cellulose acetate butyrate. -117- 200906942 [Chem. 21] Plasticizer-A IRGANOX1010

GSY-P101 (a mixture of compounds of the following structure which can be reacted with biphenyl, phosphorus trichloride and 4,6-di-t-butyl, m-cresol)

"Evaluation of the productivity of optical films" The productivity of optical films was evaluated using the following indicators of melt viscosity. The lower the melt viscosity, the better the productivity. Further, when the optical film is formed, the resin is deteriorated, and the melt viscosity is lowered by the appearance. This can be determined by measuring the color odor (coloring, b 値) of each of the following film samples. In other words, the closer the b値 is to 0, the less the deterioration of the resin is, and the more preferable is -118-200906942 (melt viscosity). For each sample of the obtained particles, the flow tester c F τ _ 5 〇〇D (Shimadzu Corporation) The temperature was tested to determine the shear rate (sec-Ι) and the melt viscosity (Pa.s). The results are shown in Table 2. &lt;Measurement conditions&gt;

Determination of temperature; 240 ° C P r e h e a t ; 2 1 0 seconds

Load ; 9·8x105Pa~3x 1 07pa Adjust the load (hammer) appropriately to the cutting speed of l〇〇~1〇〇〇〇 range<measurement temperature 2 4 0 °c for 5 points (5 point cutting speed) The shear rate and the melt viscosity at the defect were measured, and the linearity was determined to be 2 4 〇. Under the arm, the melt viscosity of the cut speed of 1000 sec·1. "Evaluation of Film Quality" The obtained optical film sample ' was evaluated by the following method. The results are shown in Table 2. (b値) From the obtained optical film 'arbitrarily, 1 取样 was taken, and b 値 was measured according to the following method, wherein the absolute 値 maximum 値 was taken as b 値. The closer you are to the cockroach, the lesser the color and the better. -119 - 200906942 b値 can be obtained according to the method described in JIS Standard Z-8 722. In the present invention, b値 was measured using a Tokyo Electric Color Co., Ltd. color analyzer TC-1800MKII type. (Changing coefficient (C V ) of the retained enthalpy) The enthalpy of the i cm interval is obtained in the width direction of the obtained optical film, which is caused by the coefficient of variation (CV) of the retained enthalpy obtained by the following formula. The measurement was performed using an automatic birefringence meter Κ Ο BURA · 2 1 AD Η (manufactured by Oji Scientific Instruments Co., Ltd.) at a wavelength of 5 90 nm in the environment of 28 ° C and 55% RH. The three-dimensional complex refractive index measurement of the interval is determined by measuring the deuteration into the sub-form. In-plane retention 値Ro=(ηχ-ny) xd Thickness direction retention 値Rt= ( ( nx + ny) /2-nz) xd where d is the film thickness (nm) and the refractive index nx (the maximum in-plane of the film) The refractive index 'is also referred to as the retardation in the slow axis direction), ny (the refractive index in the direction perpendicular to the slow axis of the film surface), and η ζ (the refractive index of the film in the thickness direction). The obtained in-plane and thickness directions were retained, and the standard deviation was obtained by each (n_i) method. The distribution of the stagnation 求 is obtained by the coefficient of variation (C V ) shown below and is used as an indicator. In the actual measurement, η is set to 1 3 0 to 1 40. Coefficient of variation (CV) = standard deviation / retention 値 average 値 ◎: deviation (CV) is less than 1.5% 〇: deviation (CV) is 1.5% or more, less than 5% -120- 200906942 △: deviation (CV) is 5 % or more, less than 10% X: Deviation (CV) is 10% or more "Adequacy of alkalization treatment" Next, the above-mentioned optical films 1-1 to 1-26 are subjected to the following alkali alkalization treatment, and then bonded. Each of the polarizing plates 1-1 to 1-26 was produced by a polarizer. (alkali alkalization treatment) alkalization step: 2 mol/L NaOH, 60 ° C, 60 seconds water washing step: water 30 ° C, 45 seconds neutralization step: 10 mass% HC1 30 ° C 45 seconds water washing step: water 3 After alkalization treatment at 0 ° C for 45 seconds, the steps were carried out in the order of water washing, neutralization, and water washing, followed by drying at 8 ° C. (Production of polarizer) The long-rolling polyvinyl alcohol film having a thickness of 120/zm is immersed in an aqueous solution containing 1 part by mass of iodine and 4 parts by mass of boric acid, and is extended to 6 times in the conveying direction at 5 〇乞. After making a polarizer. (Production of polarizing plate) The optical film produced above was bonded to both sides of the polarizing film by using an alkali-alkali-treated surface as a polarizing agent side, a fully alkalized polyvinyl alcohol 5% by mass aqueous solution as an adhesive. A polarizing plate for a protective film for polarizing plates -121 - 200906942 is attached. (Durability) Next, the evaluation was carried out at 80 ° C for one hour, and the level of the polarizer and the protective film was observed. ◎: no peeling 〇: Only a slight peeling was observed, but _ Δ: peeling was observed, which was practically X: peeling occurred, and 〇 was judged to be the level of the alkalizing treatment. 9 〇 % RH is subjected to the 1200-bonding state and is not practically used in the level of the problem of the following practical problems. -122-200906942 [I Preparation I The present invention The present invention The present invention The present invention of the present invention of the present invention of the present invention is comparatively comparatively comparatively comparatively comparatively comparatively comparatively comparatively durable I ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ 〇 ◎ ◎ &lt;;] XXX ◎ &lt;3 X &lt;3 X 〇〇 polarizing plate [sample Να r - T - CNI τ - CO τ - τ τ - LO τ - CO N - t - op r - σ &gt; τ - L 1- 10 i 1-11 ! 1-12 L 1-13 L 1-14 , 1-15 1-16 1-17 1-18 I 彳-19 I 1-20 τ— 1-22 1-23 ; 1-24 I 1-25 1-26 Variation coefficient (CV) of retained 値 ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ &lt;] XXXXXX &lt;3 XXX _Q X— 〇τ- Ο CN Ο 〇 〇 CNJ 〇τ- Ο CNJ 〇τ- Ο Ο Ο τ- Ο Ο Ο CO ο τ- Ο τ- Ο 〇Ο CO m ο IT) ο q τ— 10.3 inch CD Lf) r— seven O) CO oi oo d Optical film sample No. τ ι Τ— CN τ— 00 τ— If) VTM CO τ~ hp τ— op T~ cp τ— 1-10 1-11 1-12 1-13 [_ Γ 1-14 L_____________ LO I 1-16 I I τ— 1-18 1-19 I 1-21 I_ 1-22 CO (N τ— 1 X—to &lt;N τ— 1-26 Melt Viscosity (Pa*s) 320 360 600 460 640 520 680 460 770 340 750 __640___ 300 I 410 ι_ Γ 480 ι_ ! 920 900 ι_ ! 100 ι_ 1110 1220 I_ I 1020 I_ 260 1030 990 1400 I 1200 I Cellulose Ester No. ^— CM CO ΙΟ ΙΟ CD Bu CO Ο) Ο τ— τ— CM τ—CO ιη τ— CD 卜 CO σ&gt; o CN CNJ CsJ 00 CM LO CNJ granule sample No. τ ι CNJ τ—CO in to N- T~ op V- σ> τ — 1-10 1-11 1-12 1-13 [ 1-14 1-15 1-16 1 1 τ — 1-18 1-19 1-20 1-21 CM CN τ— CO CNJ 1 T— 1- 24 1-25 I 1-26 | -123- 200906942 The above is the result of Table 2, the optical film 1_丨~1-15 of the present invention is for the optical film ι_ΐ6~1-26 of the comparative example, It is an optical film which is good in productivity and less colored, and which has little variation in retention enthalpy. Further, since the optical film of the present invention has high alkalizability, the polarizing plate is excellent in durability and is practically excellent in optical film. Example 2 A pellet of the present invention was produced in the same manner as the pellet 1-1 of Example 1, except that the combination of the cellulose ester, the plasticizer, the deterioration preventive agent, and the ultraviolet absorber described in Table 3 was changed. ~2-18, and comparative particles 2-19, 2-20 ° Further, the optical films 2-1 to 2-18 of the present invention were produced in the same manner as in the optical film 1-1 of Example 1, and comparison Optical films 2-19, 2-20. Further, polarizing plates 2-1 to 2-18' of the present invention and comparative polarizing plates 2-19 and 2-20 were produced in the same manner as in the polarizing plate 1-1 of the first embodiment. In the plasticizer, the deterioration preventing agent, and the ultraviolet absorber in Table 3, the number of squares in the brackets is the mass part of each material used for 100 parts by mass of the cellulose ester. Further, the plasticizer-B, the plasticizer-C, the plasticizer-D, the plasticizer-E, the plasticizer-F, the plasticizer-G, the Sumilizer GP (manufactured by Sumitomo Chemical Co., Ltd.), and the TINUVIN 900 (Ciba Specialty) used in Example 2 were used. The structure of the Sumisorb 250 (manufactured by Sumitomo Chemical Co., Ltd.), -124-200906942, and LA31 (manufactured by Adeka Co., Ltd.) is as follows. -125- 200906942

-126- 200906942 [Chem. 22]

Plasticizer-C H3C〇

ο

Plasticizer-D / sucrose benzoate (a mixture of compounds of the following structure by reacting benzoic acid with sucrose)

R〇 Hr 〇 ) Γ CH2OR Η OR OR Η

Plasticizer-E I Copolymer of methyl methacrylate, methyl acrylate, and 2-hydroxyethyl ester of methacrylate (composition ratio, weight average molecular weight is as follows)

Composition ratio: p/q/r=80/10/10 Weight average molecular weight: 8,000 OH -127- 200906942

[Chemical 23] Plasticizer-F

-128 - 200906942 [Chem. 24] TINUVIN900 SUmisorb250

The pellets, optical films, and polarizing plates produced were evaluated in the same manner as in Example 1. The results are shown in Table 4. -129- 200906942 [Table 4] Particle sample No. Melt viscosity (Paes) Optical film sample No. Μ® Coefficient of variation of residual enthalpy (CV) Polarizer sample Νο_ Durability test 2-1 320 2-1 0.1 ◎ 2- 1 ◎ The present invention 2-2 340 2-2 0.1 ◎ 2-2 ◎ The present invention 2-3 330 2-3 0.2 ◎ 2-3 ◎ The present invention 2-4 330 2-4 0.1 ◎ 2-4 ◎ The present invention 2 -5 300 2-5 0.3 ◎ 2-5 ◎ The present invention 2-6 370 2-6 0.7 ◎ 2-6 〇 2-7 350 2-7 0.4 ◎ 2-7 ◎ The present invention 2-8 380 2- 8 0.1 ◎ 2-8 ◎ 2-9 410 2-9 0.1 ◎ 2-9 ◎ The present invention 2-10 500 2-10 0.1 ◎ 2-10 ◎ 2-11 510 2-11 0.3 ◎ 2- 11 ◎ The present invention 2-12 510 2-12 0.4 ◎ 2-12 〇 2-13 400 2-13 0.2 ◎ 2-13 ◎ The present invention 2-14 390 2-14 0.2 ◎ 2-14 ◎ The present invention 2 -15 430 2-15 0.1 ◎ 2-15 ◎ The present invention 2-16 450 2-16 0.5 ◎ 2-16 〇 2-17 520 2-17 0.1 ◎ 2-17 ◎ 2-18 510 2- 18 0.1 ◎ 2-18 ◎ The present invention 2-19 850 2-11 2.8 Δ 2-11 X Comparison 2-20 280 2-12 1.3 X 2-12 X Comparing the above, the results of Table 4 show that the present invention In the optical films 2 to 2 and 2 to 20 of the comparative examples, the optical films 2 to 2 and 2 to 20 of the comparative examples are optical films having less productivity and less variation in retention enthalpy. Further, the optical film of the present invention has high suitability for alkalization treatment, and the polarizing plate produced by using the polarizing plate produced by the present invention is excellent in durability and practically excellent optical film. Further, in the particles 2-1, the optical film 2-1, and the polarizing plate 2-1, the exemplified compound (2)-8 was subjected to the same evaluation with the same mass of the exemplified compound (2)-3 substituted -130-200906942' The same good results were obtained as in Test MM amp &amp; 枓N 〇, 2-1 in Table 4. Even in the same manner as described above, the exemplified compound (2)-8 was substituted with the exemplified compound (2) -45 ', and the same results as those of the sample No t! were obtained. On the one hand, in the particles 2-3, the optical film 2-3, and the polarizing plate 2_3, 〇3丫-?101 is the same mass (肆2,4___ t 甘-基) - 4,4 '一亚The biphenyl bisphosphonite substitution was carried out, and after the same evaluation, the results of the de-whitening evaluation were changed from ◎ to oxime, and the same good results as in each sample No. 2-3 of Table 4 were obtained. And in the 'particle 2-7, the optical film 2-7, and the polarizing plate 2-7, the IRG AN 0X1010 is the same mass part of the tris-hydroxymethyl group---[3-(3,5-two one t The same evaluation as in each of the samples No. 2-7 of Table 4 was obtained by substituting 'butyl-phenyl-phenylphenyl)propionic acid vinegar. Example 3 An optical film 3 of the present invention was produced in the same manner as in Example 1 except that the amount of extrusion, the drawing speed, and the stretching ratio were adjusted to 40/im using a cellulose ester and various additives. - 1, it is known that it is an optical film which is good in productivity, has less coloration, and has little variation in retention. Further, since the optical film of the present invention has high suitability for alkalization treatment, the polarizing plate produced by using the same is excellent in durability and practically excellent optical film -131 - 200906942 cellulose ester 1

Plasticizer-A 100 parts by mass of 8 parts by mass of IRGANOX 1010 (manufactured by Ciba Specialty Chemicals Co., Ltd.) 0 · 5 parts by mass 〇 · 25 parts by mass 0.30 parts by mass GSY-P101 (manufactured by Sigma Chemical Industry Co., Ltd.) exemplified compound (2 ) - 8 TINUVIN928 (manufactured by Ciba Specialty Chemicals Co., Ltd.) 2·25 parts by mass of Example 4 [Production of optical film] Using the particles 10 obtained in Example 1, optical films 4-1 and 4-2 were produced in the following manner. After the pellet 1 was dried at 100 ° C for 4 hours, it was heated and melted in a nitrogen atmosphere at 25 ° C, and then melt-extruded by a T-die to adjust the protrusion (lip) clearance to obtain a film. The optical film 4-1 having a film thickness of 80 &quot; m which is not extended in the width direction. The particles 10 are dried at 10 CTC for 4 hours, and then heated and melted at 25 ° C under a nitrogen atmosphere to be T. The mold is adjusted and protruded (ΗΡ), and the film is melt-extruded under the clearance, and stretched 13 times in the width direction of 160 ° C to obtain an optical film 4 - 2 having a film thickness of 80 μm. For these samples, The definitions of Ro and Rt were determined. The results are shown in Table 5. -132 - 200906942 [Table 5] Thin film sample No. Ro (nm) Rt (nm) Preparation 4-1 0 1 The present invention 4-2 3 1 The present invention or higher As is apparent from the results of Table 5, the optical films 4 _ 1 and 4-2 of the present invention are optically isotropic when R 〇 and Rt are close to each other. Example 5 (Assessment of characteristics of a liquid crystal display device) The polarizing plates of the Sharp type 32 TV AQ-32AD5 manufactured by the Sharp type VA liquid crystal display device were peeled off, and the polarizing plates produced in Examples 1 to 3 were implemented. The sample of the polarizing plate of the present invention produced in Example 3 was cut as 3d. The size of the liquid crystal cell was cut. The liquid crystal cell was sandwiched, and the polarizing plate 2 prepared as described above was attached to the polarizing axis of the polarizing plate. The liquid crystal display using the polarizing plates 1-1 to 1-15, 2d to 2_18, and 3-1 of the present invention is obtained by directly evaluating each other to produce a 32-type VA type color liquid crystal display and evaluating the characteristics of the polarizing plate as an optical film. Compared with the liquid crystal display device using the comparative polarizing plates 1-16 to 丨26, 2_1 9 and 2-20, the device has a high contrast and exhibits excellent displayability without causing color unevenness. It is an excellent polarizing plate when it is used as a polarizing plate for a video display device, such as a liquid crystal display. [FIG. 1] FIG. 1 shows an implementation of the apparatus for carrying out the manufacturing method of the optical film of this invention. [Fig. 2] A flow chart showing an enlargement of an important part of the manufacturing apparatus of Fig. 1. Fig. 3 (a) shows an external view of an important part of a casting mold, and Fig. 3 (b) shows A cross-sectional view of the important part of the casting mold. [Fig. 4] Fig. 5 is a cross-sectional view showing a second embodiment of the squeezing rotor in a plane perpendicular to the rotation axis. [Fig. 6] Fig. 6 is a view showing the second embodiment of the squeezing rotor. Fig. 7 is an exploded perspective view showing a schematic configuration of a liquid crystal display device. Fig. 8 is a view showing a state in which an optical film roll is stored. [Description of main component symbols] 1 : Extruder 2 : Filter 3 : Static stirrer 4 : Casting mold 5 : Rotating support (first cooling roll) 6 : Clamping rotating body (contact roll) 7 : Rotating support (second cooling roll) 8 : Rotating support (third cooling roller) 9, 1, 1 , 1 3, 14, 1 5 : conveying roller -134 - 200906942 1 〇 __ optical film 1 2 : stretching machine 1 6 : winding device 2 1 a ' 2 1 b : protective film 22a, 22b: retardation film 23a, 23b: retardation axis direction 24a, 24b of film: transmission axis direction of polarizer 2 5 a, 2 5 b : polarizer 26a, 26b: polarized light Plate 2 7 : Liquid crystal cell 2 9 '·Liquid crystal display device 3 1 : Mold body 3 2 : Slot 41 : Metal sleeve 42 : Elastic roller 43 : Metal inner tube 4 4: rubber 4 5 : cooling water 5 1 : outer cylinder 52 : inner cylinder 5 3 : space 5 4 : cooling liquid 55a, 55b: rotating shaft 56a, 56b: outer cylinder supporting flange - 135 - 200906942 60 : fluid shaft cylinder 61a, 61b: inner cylinder support flange 6 2 a, 6 2 b : intermediate passage 1 10 : core body 1 1 7 : support plate 1 1 8 : gantry 120: optical film original roll - 136-

Claims (1)

200906942 X. Patent Application No. 1. An optical film characterized in that an optical film contains a cellulose ester, which is a type of substituent per 1 glucose unit of the cellulose ester, and the degree of substitution is simultaneously satisfying the following formula (1) Conditions of ~(3); Equation (1) 6 3 0 芸2 χχ + 3 XYS 7.50 Equation (2) l.lOSYsu Equation (3) 0.30SY6^0.50 [wherein 'X denotes the second digit , the total substitution degree of the third and sixth amino groups, Y represents the total of the average substitution degrees of the second, third, and sixth propyl groups, and Y6 represents the The average degree of substitution of the 6-position propyl sulfhydryl group]. 2. The optical film of claim 1, wherein the cellulose ester has a weight average molecular weight of 150,000 or more and less than 250,000. 3. The optical film of claim 1 or 2, wherein the optical film is a phenolic compound. 4. The optical film according to any one of the first to third aspects of the invention, wherein the optical film is a compound containing a phosphorus compound. 5. An optical film as claimed in any one of claims 1 to 4 wherein the optical film is an alkyl radical scavenger. The optical film of any one of the above-mentioned claims, wherein the phenolic compound is a hindered phenolic compound. 7. The optical film according to any one of claims 4 to 6, wherein the phosphorus-based antioxidant compound is a phosphonite-based compound. 8. The optical-137-200906942 film according to any one of claims 5 to 7, wherein the alkyl radical scavenger is a compound represented by the following general formula (1) or the following general formula ( 2) the compound shown; [wherein, Ri represents no hydrogen atom or a carbon number of 1 to 10, and R2 and R3 each independently represent an alkyl group having 1 to 8 carbon atoms] - General formula (2) Wherein r12 to r15 each independently represent a hydrogen atom or a substituent, R16 represents a hydrogen atom or a substituent, η represents an integer of 1 to 4; when η is 1, Rm represents a substituent, and η is an integer of 2 to 4; And Rh represents a 2 to 4 valent linking group: and the substituent represents an alkyl group, a cycloalkyl group, an aryl group, a decylamino group, an alkylthio group, an arylthio group, an alkenyl group, a halogen atom, an alkynyl group, or a hetero Cycloalkyl, alkylsulfonyl, arylsulfonyl, alkylsulfinyl, arylsulfinyl, phosphonium, fluorenyl, aminomethyl sulfhydryl, amine sulfonyl, sulfonamide Base, cyano, alkoxy, aryloxy, heterocyclooxy, decyloxy, decyloxy, sulfonate 'sulfonic acid salt, aminocarbonyloxy, amine, anilino, imine A ureido group, a ureido group, an alkoxycarbonylamino group, an alkoxycarbonyl group, an aryloxycarbonyl group, a heterocyclic thio group, a thiourea group, a carboxyl group, a salt of a carboxylic acid, a hydroxyl group, a thiol group, or a nitro group. A method for producing an optical film, which is characterized in that the optical film of any one of items 1 to 8 of the patent application is produced by a melt casting method. 10. A polarizing plate </ RTI> characterized in that at least one side of the polarizer has an optical film as in the first to eighth aspects of the patent application. A liquid crystal display device characterized in that a polarizing plate according to the first aspect of the invention is used for at least one surface of a liquid crystal cell. -139-