JP2005157038A - Polarizer plate and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizer plate which is low-cost and has improved durability and to provide a display device using the same. <P>SOLUTION: The polarizer plate is used for a display device on which an image is displayed and observed through at least one polarizer. The polarizer plate comprises a polarizer and at least two films A and B, and the film A is further from the display device than the polarizer, and the film B is nearer to the display device than the polarizer, and the films meet conditions that the amount of an ultraviolet absorbent, the amount of a degradation inhibitor, the amount of a retardation improver, a retardation value, and film materials are within satisfying amount ranges. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a polarizing plate used for a display device, particularly a polarizing plate used for a liquid crystal display device, and a display device using the polarizing plate.

  For the purpose of protecting the polarizer, a triacetyl cellulose (TAC) film having substantially zero in-plane retardation is used. This TAC film is a polarizing plate having a structure in which both sides of a polarizer are sandwiched. In recent years, the function of a retardation film has been fused with a polarizing plate protective film typified by TAC, and the role of the protective film has become multifunctional. Therefore, there is a need for a polarizing plate with enhanced resistance due to changes in the use environment.

  Deterioration prevention technology is important for improving the resistance of polarizing plates. For example, deterioration prevention technology due to ultraviolet rays is disclosed in JP-A-2000-193821 and JP-A-2001-272682. This is for the purpose of protecting the polarizer by using an ultraviolet absorber.

  To improve the resistance of the polarizing plate, a deterioration inhibitor (eg, antioxidant, peroxide decomposer, radical inhibitor, metal deactivator, acid scavenger, amine, etc.) may be added. The deterioration preventing agents are described in JP-A-3-199201, JP-A-51907073, JP-A-5-194789, JP-A-5-271471, and JP-A-6-107854.

  Flat panel displays typified by liquid crystal display devices, organic EL, PDP, etc. are becoming larger, diversified in size for mobile applications, etc. Contrast in display quality, hue control with colorization, higher definition, or liquid crystal Display devices have problems such as viewing angle control, and there is an increasing demand for quality improvement.

  Recently, the viewing angle compensation of the TFT-TN liquid crystal display is being improved, and as disclosed in JP-A-7-191217, a discotic liquid crystal film is disposed on the upper and lower surfaces of the liquid crystal cell, It is disclosed that the viewing angle characteristics of a liquid crystal cell can be improved.

  A technique that can improve the viewing angle by improving the liquid crystal mode is disclosed. For example, JP-A-2-176625 uses a vertical alignment (VA) liquid crystal mode liquid crystal cell in which a liquid crystal compound is aligned substantially vertically when no voltage is applied and is aligned substantially horizontally when a voltage is applied. A liquid crystal display device is disclosed. The VA liquid crystal mode is characterized by having a wider viewing angle and faster response than the conventional liquid crystal mode, but it still needs to be improved compared to the CRT. The viewing angle of 45 °, 135 °, 225 °, and 315 ° directions is desired to be improved, and a viewing angle compensation film may be used for the improvement.

  On the other hand, there is a liquid crystal mode in which liquid crystal molecules are oriented obliquely with respect to the substrate when displaying a halftone between a black level and a white level. For this reason, the angle of the apparent liquid crystal molecules with respect to the substrate differs depending on the viewing angle, and the brightness appears different. In the case of color display, it looks as a different color.

  In order to solve this problem, a single pixel is divided into a plurality of parts for the purpose of wide viewing angle and high contrast, and the direction of the liquid crystal tilting surface is changed by the electric field in each divided region, thereby making the liquid crystal display by multi-domain. A method of manufacturing the device has been reported. In this method, a mask rubbing method (for example, refer to Non-Patent Document 1) for rubbing while moving a mask having a predetermined shape, a method by applying a plurality of alignment film materials (for example, refer to Non-Patent Document 2), There is a method of changing the characteristics of the alignment film by irradiation with ultraviolet rays or the like (see, for example, Patent Document 1).

  Viewing angle expansion by a compensation film is used in combination with a multi-domain technology, and is also being studied for the VA mode. A combined use of an A plate and a C plate (for example, see Non-Patent Document 3) has been proposed as a compensation film.

In recent years, the demand for TV as a display centering on moving image display and the demand for mobile devices that are susceptible to fluctuations in the external environment have been increasing, and both display quality improvement and durability have been remarkably improved. Development of a polarizing plate and a display device including the polarizing plate is desired.
Japanese Patent Laid-Open No. 5-210099 K. Takatori et. al. "A Completely TN LCD with Wide-Viewing Angle Grayscale", Japan Display '92, pp591. T.A. Kamada et. al. , “Wide Viewing Angle Full-Color TFT LCDs”, Japan Display '92, pp 886. J. et al. Chen et. al. : SID '98 Digest (1998), p315

  An object of the present invention is to provide a polarizing plate having low cost and improved durability, and a display device using the polarizing plate. In particular, a polarizing plate suitable for a liquid crystal display device and a liquid crystal display device with improved display quality by the polarizing plate are provided.

The object of the present invention with respect to the above problems is achieved by the following configuration.
(Claim 1)
In a polarizing plate used for a display device that displays and observes an image of a display device through at least one polarizing plate, the polarizing plate is composed of a polarizer and at least two films A and B, and the film A is a polarizer. A polarizing plate characterized in that it is present on the side farther from the display device, and the film B is present on the side closer to the display device than the polarizer, and satisfies all of the following relationships (1) to (4).

(1) Formula I Wa> Wb ≧ 0
Formula II 0.1 (g / m ² ) <Wa <3.0 (g / m ² )
(Wherein, Wa is the amount of the ultraviolet absorber and / or antidegradants per 1 m ² in the film ^{A (g / m 2),} Wb is the ultraviolet absorbent per 1 m ² in the film B and / or antidegradants Represents the amount (g / m ² ).)
(2) Formula III 0 ≦ Ra ≦ Rb
Formula IV 0 (g / m ² ) ≦ Rb ≦ 3.0 (g / m ² )
(In the formula, Ra represents the amount of retardation improver per 1 m ² of film A (g / m ² ), and Rb represents the amount of retardation improver per 1 m ² of film B (g / m ² ).)
(3) Ro of film B defined by the following formula (V) is in the range of 20 nm to 95 nm, and Rth of film B defined by the following formula (VI) is in the range of 70 nm to 400 nm. Here, Ro and Rth are retardation values of 590 nm, and are measured values in an environment of 23 ° C. and 55% RH.

Formula V Ro = (nx−ny) × d
Formula VI Rth = {(nx + ny) / 2−nz} × d
(Where nx is the refractive index in the slow axis direction in the film plane, ny is the refractive index in the fast axis direction in the film plane, nz is the refractive index in the thickness direction of the film, and d is Represents film thickness.)
(4) Film A is a cellulose acetate film or a cellulose acetate propionate film, and film B is a cellulose acetate propionate film.
(Claim 2)
The polarizing plate according to claim 1, wherein the film A and the film B satisfy a relationship between the following formulas VII and VIII.

Formula VII 0.1 (g / m ² ) <(Wa + Ra) <3.0 (g / m ² )
Formula VIII 0 (g / m ² ) ≦ (Wb + Rb) <3.0 (g / m ² )
(Claim 3)
The polarizing plate according to claim 1 or 2, wherein at least one of the film A and the film B contains a plasticizer in an amount of 1% by mass to less than 11% by mass with respect to the film mass.
(Claim 4)
The film A is a cellulose acetate film, and the film B is a cellulose ester having a total acyl group substitution degree of 2.5 to 2.9 and an acetyl group substitution degree of 1.4 to 2.3. It is a cellulose-ester film which is a range, The polarizing plate of any one of Claims 1-3 characterized by the above-mentioned.
(Claim 5)
The polarizing plate according to claim 1, wherein the cellulose acetate film contains an ultraviolet absorber, and the ultraviolet absorber is a benzophenone derivative or a benzotriazole derivative.
(Claim 6)
The polarizing plate according to claim 1, wherein the retardation improver is a compound having a 1,3,5-triazine ring.
(Claim 7)
7. The film according to claim 1, wherein at least one of the film A and the film B is produced by a solution casting method, and the retardation is controlled by stretching in the presence of a residual solvent. 2. A polarizing plate according to item 1.
(Claim 8)
The polarizing plate according to claim 1, wherein the film A and the film B are bonded to a polarizer by a saponification treatment.
(Claim 9)
The retardation value of the said film A and the film B differs, The polarizing plate of any one of Claims 1-8 characterized by the above-mentioned.
(Claim 10)
The polarizing plate according to claim 1, wherein the film B satisfies 30 nm <Ro ≦ 70 nm.
(Claim 11)
The polarizing plate according to claim 1, wherein the film B satisfies 90 nm <Rth ≦ 200 nm.
(Claim 12)
It is a polarizing plate of any one of Claims 1-11, Comprising: The transmission axis of a polarizer is substantially parallel with respect to a roll elongate direction, and the slow axis of the film B is a roll width direction. A roll-shaped polarizing plate characterized by being substantially parallel to.
(Claim 13)
A display device using the polarizing plate according to any one of claims 1 to 11 or the roll-shaped polarizing plate according to claim 12 is a liquid crystal display device.
(Claim 14)
The display device according to claim 13, wherein the liquid crystal display device is a multi-domain liquid crystal display device.
(Claim 15)
The display device according to claim 13, wherein the liquid crystal display device is in a vertical alignment mode.
(Claim 16)
The display device according to any one of claims 13 to 15, wherein two polarizing plates are respectively polarizing plate 1 (film A1 / polarizer / film B1) and polarizing plate 2 (film B2 / polarizer / film A2). The configuration viewed from the cross-sectional side of the display device is the order of polarizing plate 1 (film A1 / polarizer / film B1) / liquid crystal cell / polarizing plate 2 (film B2 / polarizer / film A2), and The arrangement when observed from the vertical direction of the surface of the display device is that the transmission axes of the two polarizing plates are substantially perpendicular, the film B1 and the film B2 are substantially the same film, the film B1 and the film A display device, wherein a slow axis of B2 is substantially parallel to a transmission axis of an adjacent polarizer.
(Claim 17)
The display device according to claim 13, wherein the display device displays a moving image and a color.

  According to the present invention, it is possible to provide a polarizing plate with low cost and improved durability, and a display device using the polarizing plate. In particular, a polarizing plate suitable for a liquid crystal display device and a liquid crystal display device with improved display quality can be provided.

  The best mode for carrying out the present invention will be described in detail below, but the present invention is not limited thereto.

  The present invention relates to a polarizing plate used in a display device for displaying and observing an image of a display device through at least one polarizing plate, wherein the polarizing plate is composed of a polarizer and at least two films A and B. A is present on the side farther from the polarizer to the display device, and the film B is present on the side closer to the display device than the polarizer, and satisfies all of the following relationships (1) to (4): Achieved by a polarizing plate.

(1) Formula I Wa> Wb ≧ 0
Formula II 0.1 (g / m ² ) <Wa <3.0 (g / m ² )
(Wherein, Wa is the amount of the ultraviolet absorber and / or antidegradants per 1 m ² in the film ^{A (g / m 2),} Wb is the ultraviolet absorbent per 1 m ² in the film B and / or antidegradants Represents the amount (g / m ² ).)
(2) Formula III 0 ≦ Ra ≦ Rb
Formula IV 0 (g / m ² ) ≦ Rb ≦ 3.0 (g / m ² )
(In the formula, Ra represents the amount of retardation improver per 1 m ² of film A (g / m ² ), and Rb represents the amount of retardation improver per 1 m ² of film B (g / m ² ).)
(3) Ro of film B defined by the following formula (V) is in the range of 20 nm to 95 nm, and Rth of film B defined by the following formula (VI) is in the range of 70 nm to 400 nm. Here, Ro and Rth are retardation values of 590 nm, and are measured values in an environment of 23 ° C. and 55% RH.

Formula V Ro = (nx−ny) × d
Formula VI Rth = {(nx + ny) / 2−nz} × d
(Where nx is the refractive index in the slow axis direction in the film plane, ny is the refractive index in the fast axis direction in the film plane, nz is the refractive index in the thickness direction of the film, and d is Represents film thickness.)
(4) Film A is a cellulose acetate film or a cellulose acetate propionate film, and film B is a cellulose acetate propionate film.

  For the film used in the present invention, the plasticizer, ultraviolet absorber, deterioration inhibitor and retardation improver described below can be used within the scope of the present invention.

When the polarizing plate of the present invention is a display cell, particularly preferably a liquid crystal cell, Wa (amount of ultraviolet absorber and / or degradation inhibitor) is added to the film A in order to maintain the quality of the display cell and the polarizer. From the viewpoint of achieving the object of the present invention, it is more than 0.1 (g / m ² ) and less than 3.0 (g / m ² ) with respect to the resin constituting the film. More preferably, it is more than 0.2 (g / m ² ) and less than 2.5 (g / m ² ). If the amount of the ultraviolet absorber and / or the deterioration preventing agent is less than the range of the present invention, the improvement in durability, which is the object of the present invention, is not exhibited, and the amount of the ultraviolet absorber and / or the deterioration preventing agent is the present amount. When the amount is larger than the range of the invention, it is not preferable in terms of affecting the transparency of the film. Here, the resin constituting the film is cellulose acetate or cellulose acetate propionate which is a cellulose ester.

In the polarizing plate of the present invention, Wb (amount of ultraviolet absorber and / or deterioration inhibitor per 1 m ²⁾ contained in the film B satisfies Wa> Wb ≧ 0 with respect to the resin constituting the film. Yes, and more preferably, Wa> Wb = 0. Here, the resin constituting the film is cellulose acetate propionate which is a cellulose ester.

  This is because film A can contain a larger amount of at least one UV absorber and / or anti-degradation agent than film B, so that the protection of the polarizer and the deterioration of the display cell can be efficiently suppressed. In addition, since the function expression is effectively exhibited by this efficiency improvement, it can contribute to the cost reduction. In the film B, the presence of the ultraviolet absorber and / or the deterioration preventing agent can be appropriately controlled within the scope of the present invention in order to maintain the quality of the display cell.

  On the other hand, when the polarizing plate of the present invention is a display cell, particularly preferably a liquid crystal cell, the retardation value in the film B is appropriately controlled in order to improve the display quality of the present invention. For this reason, it is calculated | required in control of the retardation value to add the below-mentioned retardation improving agent to the film which protects the polarizing plate of this invention.

Rb (retardation improver amount per 1 m ² ) of film B is 0 (g / m ² ) or more and 3.0 (g / m ² ) or less with respect to the cellulose ester constituting the film. From the viewpoint of achieving the object of the present invention, it is preferable. More preferably, it is 0 (g / m ² ) or more and 2.5 (g / m ² ) or less.

  When the amount of the retardation improver is near the lower limit of the range of the present invention, in order to obtain the retardation necessary for improving the display quality which is the object of the present invention, the substituent of cellulose acetate propionate is It is possible to appropriately control within the range. On the other hand, when the amount of the retardation improver is larger than the range of the present invention, it is not preferable because it affects the transparency of the film.

In the polarizing plate of the present invention, Rb (retardation improving agent amount per 1 m ² ) contained in the film B is to satisfy 0 ≦ Ra ≦ Rb with respect to the resin constituting the film, and more preferably, 0 = Ra ≦ Rb is satisfied.

  The expression of retardation for improving display quality, which is the object of the present invention, is the amount of cellulose acetate propionate and retardation improver whose acyl group species and their degree of substitution are appropriately controlled within the scope of the present invention. , And the conditions of the film forming process described later.

The polarizing plate according to the present invention can be used on at least one of the observation surfaces of the display device according to the display design. In a liquid crystal display device, it can be used in place of a known polarizing plate, and the object of the present invention is efficient when images on the display device are displayed and observed through at least one polarizing plate of the present invention. Can be demonstrated. In the film A and the film B in the polarizing plate of the present invention, particularly preferably 0.1 (g / m ² ) <(Wa + Ra) <3.0 (g / m ² ) and 0 (g / m ^2). ) ≦ (Wb + Rb) <3.0 (g / m ² ). This is because when (Wa + Ra) is less than the range of the present invention, the object of the present invention cannot be expressed, and when (Wa + Ra) and (Wb + Rb) are more than the range of the present invention, the wet heat storage stability of the polarizing plate is deteriorated. However, it is not preferable in terms of cost because a large amount of expensive additives are used.

  First, a production example of a cellulose ester film used for the polarizing plate of the present invention will be described for an optically biaxial polymer film produced by an in-line stretching operation following the solution casting used in the present invention.

  As a method for producing the cellulose ester film used in the present invention, a dope solution prepared by dissolving cellulose ester is cast on a support (stainless belt, etc.) and formed into a film, and the resulting film is peeled off from the support (peeling). In addition, a solution casting film forming method is preferable in which the film is stretched by applying a tension in the width direction while containing a certain amount of residual solvent, and dried while being conveyed in the drying zone. This is because that the necessary retardation characteristics are uniform within the display display region contributes to reduction of display unevenness.

  Hereinafter, the solution casting film forming method according to the manufacturing method of the present invention will be described. In addition, a longitudinal direction (MD) represents a base material conveyance direction and dope casting direction, and a width direction (TD) represents the direction orthogonal to a longitudinal direction in a film surface.

  (1) Dissolution step: an organic solvent mainly composed of a good solvent for cellulose ester (flakes, powders or granules, preferably particles having an average particle size of 100 μm or more), and the cellulose ester and additives in a dissolution vessel Is dissolved with stirring to form a dope. There are various dissolution methods, such as a method performed at normal pressure, a method performed below the boiling point of the good solvent, a method performed under pressure above the boiling point of the good solvent, a method performed using the cooling dissolution method, and a method performed at high pressure. After dissolution, the dope is filtered with a filter medium, defoamed, and sent to the next process with a pump.

  Said dope is the solution which melt | dissolved the cellulose ester and the additive mentioned later in the organic solvent.

  The cellulose used as a raw material for the cellulose ester used in the present invention is not particularly limited, and examples thereof include cotton linter, wood pulp, and kenaf. Moreover, the cellulose ester obtained from them can be mixed and used in arbitrary ratios, respectively.

In the cellulose ester according to the present invention, when the acylating agent of the cellulose raw material is an acid anhydride (acetic anhydride, propionic anhydride), an organic solvent such as acetic acid or an organic solvent such as methylene chloride is used. The reaction is carried out using such a protic catalyst. When the acylating agent is acid chloride (CH ₃ COCl, C ₂ H ₅ COCl), the reaction is carried out using a basic compound such as an amine as a catalyst. Specifically, it can be synthesized with reference to the method described in JP-A-10-45804. In the cellulose ester, the acyl group reacts with the hydroxyl group of the cellulose molecule. Cellulose molecules are composed of many glucose units linked together, and the glucose unit has three hydroxyl groups. The number of acyl groups derived from these three hydroxyl groups is called the degree of substitution. For example, cellulose triacetate has an acetyl group bonded to all three hydroxyl groups of the glucose unit.

  The cellulose acetate propionate used in the present invention may be used by mixing two or more types of cellulose esters having different substitution degrees. In this case, the substitution degree after mixing and the total substitution degree are within the scope of the present invention. May be used.

  The degree of substitution used in the cellulose acetate propionate film used in the films A and B in the present invention is not particularly limited. It is preferable that the degree of substitution is in the range of 2.5 to 2.9 and the degree of acetyl substitution is in the range of 1.4 to 2.3. The range of the total acyl group substitution degree is more preferably in the range of 2.5 to 2.8, still more preferably in the range of 2.6 to 2.75 for the purposes of the present invention.

  The measuring method of the substitution degree of an acyl group can be measured according to ASTM-D817-96.

  The number average molecular weight of the cellulose ester used in the present invention is preferably in the range of 50,000 to 300,000 because the mechanical strength of the resulting film is strong. Furthermore, the thing of 60000-200000 is used preferably.

  The number average molecular weight of the cellulose ester can be measured as follows. Measured by high performance liquid chromatography under the following conditions.

Solvent: Acetone Column: MPW × 1 (manufactured by Tosoh Corporation)
Sample concentration: 0.2 (mass / volume)%
Flow rate: 1.0 ml / min Sample injection volume: 300 μl
Standard sample: Polymethyl methacrylate Temperature: 23 ° C
In addition, cellulose acetate propionate or cellulose acetate is used as film A, but preferably cellulose acetate, more preferably a film having an acetylation degree of 59.0 to 62.0% for the purpose of the present invention. Preferably used. The degree of acetylation means the amount of bound acetic acid per unit mass of cellulose, and follows the measurement and calculation of the degree of acetylation in ASTM-D817-91.

<Retardation improver>
As the compound to be added for adjusting the retardation, an aromatic compound having two or more aromatic rings as described in EP 911,656A2 can be used.

  Two or more aromatic compounds may be used in combination. The aromatic ring of the aromatic compound includes an aromatic heterocyclic ring in addition to the aromatic hydrocarbon ring. Particularly preferred is an aromatic heterocycle, and the aromatic heterocycle is generally an unsaturated heterocycle. Of these, a 1,3,5-triazine ring is particularly preferred.

  The number of aromatic rings contained in the aromatic compound is preferably 2 to 20, more preferably 2 to 12, still more preferably 2 to 8, and most preferably 3 to 6. The bond relationship between two aromatic rings can be classified into (a) a condensed ring, (b) a direct bond with a single bond, and (c) a bond through a linking group (for aromatic rings). Spiro bonds cannot be formed). The connection relationship may be any of (a) to (c).

  Examples of the condensed ring (a condensed ring of two or more aromatic rings) include an indene ring, a naphthalene ring, an azulene ring, a fluorene ring, a phenanthrene ring, an anthracene ring, an acenaphthylene ring, a naphthacene ring, a pyrene ring, Indole ring, isoindole ring, benzofuran ring, benzothiophene ring, indolizine ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring, purine ring, indazole ring, chromene ring, quinoline ring, isoquinoline ring, quinolidine Ring, quinazoline ring, cinnoline ring, quinoxaline ring, phthalazine ring, pteridine ring, carbazole ring, acridine ring, phenanthridine ring, xanthene ring, phenazine ring, phenothiazine ring, phenoxathiin ring, phenoxazine ring and thianthrene ring It is. Naphthalene ring, azulene ring, indole ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring and quinoline ring are preferred.

  The single bond (b) is preferably a bond between carbon atoms of two aromatic rings. Two aromatic rings may be bonded with two or more single bonds to form an aliphatic ring or a non-aromatic heterocyclic ring between the two aromatic rings.

  The linking group in (c) is also preferably bonded to carbon atoms of two aromatic rings. The linking group is preferably an alkylene group, an alkenylene group, an alkynylene group, —CO—, —O—, —NH—, —S—, or a combination thereof. Examples of linking groups composed of combinations are shown below. In addition, the relationship between the left and right in the following examples of the linking group may be reversed.

  -CO-O-, -CO-NH-, -alkylene-O-, -NH-CO-NH-, -NH-CO-O-, -O-CO-O-, -O-alkylene-O-, -CO-alkenylene-, -CO-alkenylene-NH-, -CO-alkenylene-O-, -alkylene-CO-O-alkylene-O-CO-alkylene-, -O-alkylene-CO-O-alkylene-O -CO-alkylene-O-, -O-CO-alkylene-CO-O-, -NH-CO-alkenylene-, -O-CO-alkenylene-.

  The aromatic ring and the linking group may have a substituent. Examples of the substituent include halogen atom (F, Cl, Br, I), hydroxyl, carboxyl, cyano, amino, nitro, sulfo, carbamoyl, sulfamoyl, ureido, alkyl group, alkenyl group, alkynyl group, aliphatic acyl group , Aliphatic acyloxy group, alkoxy group, alkoxycarbonyl group, alkoxycarbonylamino group, alkylthio group, alkylsulfonyl group, aliphatic amide group, aliphatic sulfonamido group, aliphatic substituted amino group, aliphatic substituted carbamoyl group, aliphatic Substituted sulfamoyl groups, aliphatic substituted ureido groups and non-aromatic heterocyclic groups are included.

  It is preferable that the alkyl group has 1 to 8 carbon atoms. A chain alkyl group is preferable to a cyclic alkyl group, and a linear alkyl group is particularly preferable. The alkyl group may further have a substituent (eg, hydroxy, carboxy, alkoxy group, alkyl-substituted amino group). Examples of alkyl groups (including substituted alkyl groups) include methyl, ethyl, n-butyl, n-hexyl, 2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl and 2-diethylaminoethyl. The alkenyl group preferably has 2 to 8 carbon atoms. A chain alkenyl group is preferable to a cyclic alkenyl group, and a linear alkenyl group is particularly preferable. The alkenyl group may further have a substituent. Examples of alkenyl groups include vinyl, allyl and 1-hexenyl. The alkynyl group preferably has 2 to 8 carbon atoms. A chain alkynyl group is preferable to a cyclic alkynyl group, and a linear alkynyl group is particularly preferable. The alkynyl group may further have a substituent. Examples of alkynyl groups include ethynyl, 1-butynyl and 1-hexynyl.

  The aliphatic acyl group preferably has 1 to 10 carbon atoms. Examples of the aliphatic acyl group include acetyl, propanoyl and butanoyl. The number of carbon atoms in the aliphatic acyloxy group is preferably 1-10. Examples of the aliphatic acyloxy group include acetoxy. The alkoxy group preferably has 1 to 8 carbon atoms. The alkoxy group may further have a substituent (eg, an alkoxy group). Examples of alkoxy groups (including substituted alkoxy groups) include methoxy, ethoxy, butoxy and methoxyethoxy. The alkoxycarbonyl group preferably has 2 to 10 carbon atoms. Examples of the alkoxycarbonyl group include methoxycarbonyl and ethoxycarbonyl. The number of carbon atoms of the alkoxycarbonylamino group is preferably 2-10. Examples of the alkoxycarbonylamino group include methoxycarbonylamino and ethoxycarbonylamino.

  The alkylthio group preferably has 1 to 12 carbon atoms. Examples of the alkylthio group include methylthio, ethylthio and octylthio. The alkylsulfonyl group preferably has 1 to 8 carbon atoms. Examples of the alkylsulfonyl group include methanesulfonyl and ethanesulfonyl. The number of carbon atoms in the aliphatic amide group is preferably 1-10. Examples of the aliphatic amide group include acetamide. The number of carbon atoms of the aliphatic sulfonamide group is preferably 1-8. Examples of the aliphatic sulfonamido group include methanesulfonamido, butanesulfonamido and n-octanesulfonamido. The number of carbon atoms of the aliphatic substituted amino group is preferably 1-10. Examples of the aliphatic substituted amino group include dimethylamino, diethylamino and 2-carboxyethylamino. The aliphatic substituted carbamoyl group preferably has 2 to 10 carbon atoms. Examples of the aliphatic substituted carbamoyl group include methylcarbamoyl and diethylcarbamoyl. The number of carbon atoms in the aliphatic substituted sulfamoyl group is preferably 1-8. Examples of the aliphatic substituted sulfamoyl group include methylsulfamoyl and diethylsulfamoyl. The number of carbon atoms in the aliphatic substituted ureido group is preferably 2-10. Examples of the aliphatic substituted ureido group include methylureido. Examples of non-aromatic heterocyclic groups include piperidino and morpholino.

  The molecular weight of the retardation improver is preferably 300 or more and 800 or less. This can arbitrarily select the polarity of the molecular structure from the viewpoint of suppressing the outflow at the time of use and processing of the polarizing plate.

  Among them, the compound having a 1,3,5-triazine ring is preferably a compound represented by the following general formula (I).

In the general formula (I), X ¹ is a single bond, —NR ₄ —, —O— or —S—; X ² is a single bond, —NR ₅ —, —O— or —S—; X ³ is a single bond, —NR ₆ —, —O— or —S—; R ¹ , R ² and R ³ are an alkyl group, an alkenyl group, an aryl group or a heterocyclic group; and R ₄ , R ₅ and R ₆ are a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group. The compound represented by the general formula (I) is particularly preferably a melamine compound.

In the melamine compound, in the general formula (I), X ¹ , X ² and X ³ are —NR ₄ —, —NR ₅ — and —NR ₆ —, respectively, or X ¹ , X ² and X 3 ³ is a single bond, and R ¹ , R ² and R ³ are heterocyclic groups having a free valence on the nitrogen atom. ^{-X 1 -R 1, -X 2 -R} 2 and -X ³ -R ³ are preferably the same substituents. R ¹ , R ² and R ³ are particularly preferably aryl groups. R ₄ , R ₅ and R ₆ are particularly preferably a hydrogen atom.

  The alkyl group is preferably a chain alkyl group rather than a cyclic alkyl group. A linear alkyl group is preferred to a branched alkyl group.

  The number of carbon atoms of the alkyl group is preferably 1-30, more preferably 1-20, still more preferably 1-10, still more preferably 1-8, 6 is most preferred. The alkyl group may have a substituent.

  Specific examples of the substituent include a halogen atom, an alkoxy group (for example, each group such as methoxy, ethoxy, and epoxyethyloxy) and an acyloxy group (for example, acryloyloxy, methacryloyloxy). The alkenyl group is preferably a chain alkenyl group rather than a cyclic alkenyl group. A linear alkenyl group is preferable to a branched chain alkenyl group. The number of carbon atoms in the alkenyl group is preferably 2 to 30, more preferably 2 to 20, still more preferably 2 to 10, still more preferably 2 to 8, 6 is most preferred. The alkenyl group may have a substituent.

  Specific examples of the substituent include a halogen atom, an alkoxy group (for example, each group such as methoxy, ethoxy, and epoxyethyloxy) or an acyloxy group (for example, each group such as acryloyloxy and methacryloyloxy).

  The aryl group is preferably a phenyl group or a naphthyl group, and particularly preferably a phenyl group. The aryl group may have a substituent.

  Specific examples of the substituent include, for example, a halogen atom, hydroxyl, cyano, nitro, carboxyl, alkyl group, alkenyl group, aryl group, alkoxy group, alkenyloxy group, aryloxy group, acyloxy group, alkoxycarbonyl group, alkenyloxy Carbonyl group, aryloxycarbonyl group, sulfamoyl, alkyl-substituted sulfamoyl group, alkenyl-substituted sulfamoyl group, aryl-substituted sulfamoyl group, sulfonamido group, carbamoyl, alkyl-substituted carmoyl group, alkenyl-substituted carbamoyl group, aryl-substituted carbamoyl group, amide group, alkylthio Groups, alkenylthio groups, arylthio groups and acyl groups are included. The said alkyl group is synonymous with the alkyl group mentioned above.

  The alkyl group of the alkoxy group, acyloxy group, alkoxycarbonyl group, alkyl-substituted sulfamoyl group, sulfonamido group, alkyl-substituted carbamoyl group, amide group, alkylthio group and acyl group is also synonymous with the alkyl group described above.

  The said alkenyl group is synonymous with the alkenyl group mentioned above.

  The alkenyl part of the alkenyloxy group, acyloxy group, alkenyloxycarbonyl group, alkenyl-substituted sulfamoyl group, sulfonamide group, alkenyl-substituted carbamoyl group, amide group, alkenylthio group and acyl group is also synonymous with the alkenyl group described above.

  Specific examples of the aryl group include phenyl, α-naphthyl, β-naphthyl, 4-methoxyphenyl, 3,4-diethoxyphenyl, 4-octyloxyphenyl, and 4-dodecyloxyphenyl. Can be mentioned.

  Examples of the aryloxy group, acyloxy group, aryloxycarbonyl group, aryl-substituted sulfamoyl group, sulfonamido group, aryl-substituted carbamoyl group, amide group, arylthio group, and acyl group are the same as the above aryl group.

When X ¹ , X ² or X ³ is —NR—, —O— or —S—, the heterocyclic group preferably has aromaticity.

  The heterocyclic ring in the heterocyclic group having aromaticity is generally an unsaturated heterocyclic ring, preferably a heterocyclic ring having the largest number of double bonds. The heterocyclic ring is preferably a 5-membered ring, a 6-membered ring or a 7-membered ring, more preferably a 5-membered ring or a 6-membered ring, and most preferably a 6-membered ring.

  The hetero atom in the heterocyclic ring is preferably each atom such as N, S or O, and particularly preferably an N atom.

  As the heterocyclic ring having aromaticity, a pyridine ring (as the heterocyclic group, for example, each group such as 2-pyridyl or 4-pyridyl) is particularly preferable. The heterocyclic group may have a substituent. Examples of the substituent of the heterocyclic group are the same as the examples of the substituent of the aryl moiety.

When X ¹ , X ² or X ³ is a single bond, the heterocyclic group is preferably a heterocyclic group having a free valence on the nitrogen atom. The heterocyclic group having a free valence on the nitrogen atom is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring, and a 5-membered ring. Is most preferred. The heterocyclic group may have a plurality of nitrogen atoms.

  Moreover, the hetero atom in a heterocyclic group may have hetero atoms other than a nitrogen atom (for example, O atom, S atom). The heterocyclic group may have a substituent. Specific examples of the substituent of the heterocyclic group are the same as the specific examples of the substituent of the aryl moiety.

  Specific examples of the heterocyclic group having a free valence on the nitrogen atom are shown below.

  Specific examples of the compound having a 1,3,5-triazine ring are shown below.

  In addition, several R shown below represents the same group.

(1) Butyl (2) 2-Methoxy-2-ethoxyethyl (3) 5-Undecenyl (4) Phenyl (5) 4-Ethoxycarbonylphenyl (6) 4-Butoxyphenyl (7) p-Biphenylyl (8) 4 -Pyridyl (9) 2-naphthyl (10) 2-methylphenyl (11) 3,4-dimethoxyphenyl (12) 2-furyl

(14) phenyl (15) 3-ethoxycarbonylphenyl (16) 3-butoxyphenyl (17) m-biphenylyl (18) 3-phenylthiophenyl (19) 3-chlorophenyl (20) 3-benzoylphenyl (21) 3 -Acetoxyphenyl (22) 3-benzoyloxyphenyl (23) 3-phenoxycarbonylphenyl (24) 3-methoxyphenyl (25) 3-anilinophenyl (26) 3-isobutyrylaminophenyl (27) 3-phenoxy Carbonylaminophenyl (28) 3- (3-ethylureido) phenyl (29) 3- (3,3-diethylureido) phenyl (30) 3-methylphenyl (31) 3-phenoxyphenyl (32) 3-hydroxyphenyl (33) 4-Ethoxycarbonylphenyl (34) 4-butoxyphenyl (35) p-biphenylyl (36) 4-phenylthiophenyl (37) 4-chlorophenyl (38) 4-benzoylphenyl (39) 4-acetoxyphenyl (40) 4-benzoyloxyphenyl ( 41) 4-phenoxycarbonylphenyl (42) 4-methoxyphenyl (43) 4-anilinophenyl (44) 4-isobutyrylaminophenyl (45) 4-phenoxycarbonylaminophenyl (46) 4- (3-ethyl (Ureido) phenyl (47) 4- (3,3-diethylureido) phenyl (48) 4-methylphenyl (49) 4-phenoxyphenyl (50) 4-hydroxyphenyl (51) 3,4-diethoxycarbonylphenyl ( 52) 3,4-dibutoxyphenyl (53) 3 -Diphenylphenyl (54) 3,4-diphenylthiophenyl (55) 3,4-dichlorophenyl (56) 3,4-dibenzoylphenyl (57) 3,4-diacetoxyphenyl (58) 3,4-dibenzoyl Oxyphenyl (59) 3,4-diphenoxycarbonylphenyl (60) 3,4-dimethoxyphenyl (61) 3,4-dianilinophenyl (62) 3,4-dimethylphenyl (63) 3,4-diphenoxy Phenyl (64) 3,4-dihydroxyphenyl (65) 2-naphthyl (66) 3,4,5-triethoxycarbonylphenyl (67) 3,4,5-tributoxyphenyl (68) 3,4,5- Triphenylphenyl (69) 3,4,5-triphenylthiophenyl (70) 3,4,5-trichlorophenyl (71) 3,4,5-tribenzoylphenyl (72) 3,4,5-triacetoxyphenyl (73) 3,4,5-tribenzoyloxyphenyl (74) 3,4,5-triphenoxycarbonylphenyl (75) 3,4,5-trimethoxyphenyl (76) 3,4,5-trianilinophenyl (77) 3,4,5-trimethylphenyl (78) 3,4,5-triphenoxyphenyl (79 ) 3,4,5-trihydroxyphenyl

(80) phenyl (81) 3-ethoxycarbonylphenyl (82) 3-butoxyphenyl (83) m-biphenylyl (84) 3-phenylthiophenyl (85) 3-chlorophenyl (86) 3-benzoylphenyl (87) 3 -Acetoxyphenyl (88) 3-benzoyloxyphenyl (89) 3-phenoxycarbonylphenyl (90) 3-methoxyphenyl (91) 3-anilinophenyl (92) 3-isobutyrylaminophenyl (93) 3-phenoxy Carbonylaminophenyl (94) 3- (3-ethylureido) phenyl (95) 3- (3,3-diethylureido) phenyl (96) 3-methylphenyl (97) 3-phenoxyphenyl (98) 3-hydroxyphenyl (99) 4-Ethoxycarbonylphenyl (100) 4-butoxyphenyl (101) p-biphenylyl (102) 4-phenylthiophenyl (103) 4-chlorophenyl (104) 4-benzoylphenyl (105) 4-acetoxyphenyl (106) 4-benzoyloxyphenyl ( 107) 4-phenoxycarbonylphenyl (108) 4-methoxyphenyl (109) 4-anilinophenyl (110) 4-isobutyrylaminophenyl (111) 4-phenoxycarbonylaminophenyl (112) 4- (3-ethyl (Ureido) phenyl (113) 4- (3,3-diethylureido) phenyl (114) 4-methylphenyl (115) 4-phenoxyphenyl (116) 4-hydroxyphenyl (117) 3,4-diethoxycarbonylphenyl ( 118) 3 , 4-dibutoxyphenyl (119) 3,4-diphenylphenyl (120) 3,4-diphenylthiophenyl (121) 3,4-dichlorophenyl (122) 3,4-dibenzoylphenyl (123) 3,4- Diacetoxyphenyl (124) 3,4-dibenzoyloxyphenyl (125) 3,4-diphenoxycarbonylphenyl (126) 3,4-dimethoxyphenyl (127) 3,4-dianilinophenyl (128) 3,4 -Dimethylphenyl (129) 3,4-diphenoxyphenyl (130) 3,4-dihydroxyphenyl (131) 2-naphthyl (132) 3,4,5-triethoxycarbonylphenyl (133) 3,4,5- Tributoxyphenyl (134) 3,4,5-triphenylphenyl (135) 3 4,5-triphenylthiophenyl (136) 3,4,5-trichlorophenyl (137) 3,4,5-tribenzoylphenyl (138) 3,4,5-triacetoxyphenyl (139) 3,4 5-tribenzoyloxyphenyl (140) 3,4,5-triphenoxycarbonylphenyl (141) 3,4,5-trimethoxyphenyl (142) 3,4,5-trianilinophenyl (143) 3,4 , 5-trimethylphenyl (144) 3,4,5-triphenoxyphenyl (145) 3,4,5-trihydroxyphenyl

(146) phenyl (147) 4-ethoxycarbonylphenyl (148) 4-butoxyphenyl (149) p-biphenylyl (150) 4-phenylthiophenyl (151) 4-chlorophenyl (152) 4-benzoylphenyl (153) 4 -Acetoxyphenyl (154) 4-benzoyloxyphenyl (155) 4-phenoxycarbonylphenyl (156) 4-methoxyphenyl (157) 4-anilinophenyl (158) 4-isobutyrylaminophenyl (159) 4-phenoxy Carbonylaminophenyl (160) 4- (3-ethylureido) phenyl (161) 4- (3,3-diethylureido) phenyl (162) 4-methylphenyl (163) 4-phenoxyphenyl (164) 4-hydroxyphenyl

(165) phenyl (166) 4-ethoxycarbonylphenyl (167) 4-butoxyphenyl (168) p-biphenylyl (169) 4-phenylthiophenyl (170) 4-chlorophenyl (171) 4-benzoylphenyl (172) 4 -Acetoxyphenyl (173) 4-benzoyloxyphenyl (174) 4-phenoxycarbonylphenyl (175) 4-methoxyphenyl (176) 4-anilinophenyl (177) 4-isobutyrylaminophenyl (178) 4-phenoxy Carbonylaminophenyl (179) 4- (3-ethylureido) phenyl (180) 4- (3,3-diethylureido) phenyl (181) 4-methylphenyl (182) 4-phenoxyphenyl (183) 4-hydroxyphenyl

(184) phenyl (185) 4-ethoxycarbonylphenyl (186) 4-butoxyphenyl (187) p-biphenylyl (188) 4-phenylthiophenyl (189) 4-chlorophenyl (190) 4-benzoylphenyl (191) 4 -Acetoxyphenyl (192) 4-benzoyloxyphenyl (193) 4-phenoxycarbonylphenyl (194) 4-methoxyphenyl (195) 4-anilinophenyl (196) 4-isobutyrylaminophenyl (197) 4-phenoxy Carbonylaminophenyl (198) 4- (3-ethylureido) phenyl (199) 4- (3,3-diethylureido) phenyl (200) 4-methylphenyl (201) 4-phenoxyphenyl (202) 4-hydroxyphenyl

(203) phenyl (204) 4-ethoxycarbonylphenyl (205) 4-butoxyphenyl (206) p-biphenylyl (207) 4-phenylthiophenyl (208) 4-chlorophenyl (209) 4-benzoylphenyl (210) 4 -Acetoxyphenyl (211) 4-benzoyloxyphenyl (212) 4-phenoxycarbonylphenyl (213) 4-methoxyphenyl (214) 4-anilinophenyl (215) 4-isobutyrylaminophenyl (216) 4-phenoxy Carbonylaminophenyl (217) 4- (3-ethylureido) phenyl (218) 4- (3,3-diethylureido) phenyl (219) 4-methylphenyl (220) 4-phenoxyphenyl (221) 4-hydroxyphenyl

(222) phenyl (223) 4-butylphenyl (224) 4- (2-methoxy-2-ethoxyethyl) phenyl (225) 4- (5-nonenyl) phenyl (226) p-biphenylyl (227) 4-ethoxy Carbonylphenyl (228) 4-butoxyphenyl (229) 4-methylphenyl (230) 4-chlorophenyl (231) 4-phenylthiophenyl (232) 4-benzoylphenyl (233) 4-acetoxyphenyl (234) 4-benzoyl Oxyphenyl (235) 4-phenoxycarbonylphenyl (236) 4-methoxyphenyl (237) 4-anilinophenyl (238) 4-isobutyrylaminophenyl (239) 4-phenoxycarbonylaminophenyl (240) 4- ( 3-ethylureido Phenyl (241) 4- (3,3-diethylureido) phenyl (242) 4-phenoxyphenyl (243) 4-hydroxyphenyl (244) 3-butylphenyl (245) 3- (2-methoxy-2-ethoxyethyl) ) Phenyl (246) 3- (5-nonenyl) phenyl (247) m-biphenylyl (248) 3-ethoxycarbonylphenyl (249) 3-butoxyphenyl (250) 3-methylphenyl (251) 3-chlorophenyl (252) 3-phenylthiophenyl (253) 3-benzoylphenyl (254) 3-acetoxyphenyl (255) 3-benzoyloxyphenyl (256) 3-phenoxycarbonylphenyl (257) 3-methoxyphenyl (258) 3-anilinophenyl (259) 3-I Butyrylaminophenyl (260) 3-phenoxycarbonylaminophenyl (261) 3- (3-ethylureido) phenyl (262) 3- (3,3-diethylureido) phenyl (263) 3-phenoxyphenyl (264) 3 -Hydroxyphenyl (265) 2-butylphenyl (266) 2- (2-methoxy-2-ethoxyethyl) phenyl (267) 2- (5-nonenyl) phenyl (268) o-biphenylyl (269) 2-ethoxycarbonyl Phenyl (270) 2-Butoxyphenyl (271) 2-Methylphenyl (272) 2-Chlorophenyl (273) 2-Phenylthiophenyl (274) 2-Benzoylphenyl (275) 2-Acetoxyphenyl (276) 2-Benzoyloxy Phenyl (277) 2 Phenoxycarbonylphenyl (278) 2-methoxyphenyl (279) 2-anilinophenyl (280) 2-isobutyrylaminophenyl (281) 2-phenoxycarbonylaminophenyl (282) 2- (3-ethylureido) phenyl ( 283) 2- (3,3-diethylureido) phenyl (284) 2-phenoxyphenyl (285) 2-hydroxyphenyl (286) 3,4-dibutylphenyl (287) 3,4-di (2-methoxy-2) -Ethoxyethyl) phenyl (288) 3,4-diphenylphenyl (289) 3,4-diethoxycarbonylphenyl (290) 3,4-didodecyloxyphenyl (291) 3,4-dimethylphenyl (292) 3, 4-dichlorophenyl (293) 3,4-dibenzoyl Enyl (294) 3,4-diacetoxyphenyl (295) 3,4-dimethoxyphenyl (296) 3,4-di-N-methylaminophenyl (297) 3,4-diisobutyrylaminophenyl (298) 3 , 4-diphenoxyphenyl (299) 3,4-dihydroxyphenyl (300) 3,5-dibutylphenyl (301) 3,5-di (2-methoxy-2-ethoxyethyl) phenyl (302) 3,5- Diphenylphenyl (303) 3,5-diethoxycarbonylphenyl (304) 3,5-didodecyloxyphenyl (305) 3,5-dimethylphenyl (306) 3,5-dichlorophenyl (307) 3,5-dibenzoyl Phenyl (308) 3,5-diacetoxyphenyl (309) 3,5-dimethoxyphenyl (3 0) 3,5-di-N-methylaminophenyl (311) 3,5-diisobutyrylaminophenyl (312) 3,5-diphenoxyphenyl (313) 3,5-dihydroxyphenyl (314) 2,4 -Dibutylphenyl (315) 2,4-di (2-methoxy-2-ethoxyethyl) phenyl (316) 2,4-diphenylphenyl (317) 2,4-diethoxycarbonylphenyl (318) 2,4-di Dodecyloxyphenyl (319) 2,4-dimethylphenyl (320) 2,4-dichlorophenyl (321) 2,4-dibenzoylphenyl (322) 2,4-diacetoxyphenyl (323) 2,4-dimethoxyphenyl ( 324) 2,4-di-N-methylaminophenyl (325) 2,4-diisobutyrylaminopheny (326) 2,4-diphenoxyphenyl (327) 2,4-dihydroxyphenyl (328) 2,3-dibutylphenyl (329) 2,3-di (2-methoxy-2-ethoxyethyl) phenyl (330) 2,3-diphenylphenyl (331) 2,3-diethoxycarbonylphenyl (332) 2,3-didodecyloxyphenyl (333) 2,3-dimethylphenyl (334) 2,3-dichlorophenyl (335) 2, 3-dibenzoylphenyl (336) 2,3-diacetoxyphenyl (337) 2,3-dimethoxyphenyl (338) 2,3-di-N-methylaminophenyl (339) 2,3-diisobutyrylaminophenyl (340) 2,3-diphenoxyphenyl (341) 2,3-dihydroxyphenyl (342 2,6-dibutylphenyl (343) 2,6-di (2-methoxy-2-ethoxyethyl) phenyl (344) 2,6-diphenylphenyl (345) 2,6-diethoxycarbonylphenyl (346) 2, 6-didodecyloxyphenyl (347) 2,6-dimethylphenyl (348) 2,6-dichlorophenyl (349) 2,6-dibenzoylphenyl (350) 2,6-diacetoxyphenyl (351) 2,6- Dimethoxyphenyl (352) 2,6-di-N-methylaminophenyl (353) 2,6-diisobutyrylaminophenyl (354) 2,6-diphenoxyphenyl (355) 2,6-dihydroxyphenyl (356) 3,4,5-tributylphenyl (357) 3,4,5-tri (2-methoxy-2-ethoxy) Til) phenyl (358) 3,4,5-triphenylphenyl (359) 3,4,5-triethoxycarbonylphenyl (360) 3,4,5-tridodecyloxyphenyl (361) 3,4,5- Trimethylphenyl (362) 3,4,5-trichlorophenyl (363) 3,4,5-tribenzoylphenyl (364) 3,4,5-triacetoxyphenyl (365) 3,4,5-trimethoxyphenyl ( 366) 3,4,5-tri-N-methylaminophenyl (367) 3,4,5-triisobutyrylaminophenyl (368) 3,4,5-triphenoxyphenyl (369) 3,4,5 -Trihydroxyphenyl (370) 2,4,6-tributylphenyl (371) 2,4,6-tri (2-methoxy-2-ethoxyethyl) ) Phenyl (372) 2,4,6-triphenylphenyl (373) 2,4,6-triethoxycarbonylphenyl (374) 2,4,6-tridodecyloxyphenyl (375) 2,4,6-trimethyl Phenyl (376) 2,4,6-trichlorophenyl (377) 2,4,6-tribenzoylphenyl (378) 2,4,6-triacetoxyphenyl (379) 2,4,6-trimethoxyphenyl (380 ) 2,4,6-tri-N-methylaminophenyl (381) 2,4,6-triisobutyrylaminophenyl (382) 2,4,6-triphenoxyphenyl (383) 2,4,6- Trihydroxyphenyl (384) Pentafluorophenyl (385) Pentachlorophenyl (386) Pentamethoxyphenyl (38 ) 6-N-methylsulfamoyl-8-methoxy-2-naphthyl (388) 5-N-methylsulfamoyl-2-naphthyl (389) 6-N-phenylsulfamoyl-2-naphthyl (390) 5-Ethoxy-7-N-methylsulfamoyl-2-naphthyl (391) 3-methoxy-2-naphthyl (392) 1-ethoxy-2-naphthyl (393) 6-N-phenylsulfamoyl-8- Methoxy-2-naphthyl (394) 5-methoxy-7-N-phenylsulfamoyl-2-naphthyl (395) 1- (4-methylphenyl) -2-naphthyl (396) 6,8-di-N- Methylsulfamoyl-2-naphthyl (397) 6-N-2-acetoxyethylsulfamoyl-8-methoxy-2-naphthyl (398) 5-acetoxy-7- N-phenylsulfamoyl-2-naphthyl (399) 3-benzoyloxy-2-naphthyl (400) 5-acetylamino-1-naphthyl (401) 2-methoxy-1-naphthyl (402) 4-phenoxy-1 -Naphtyl (403) 5-N-methylsulfamoyl-1-naphthyl (404) 3-N-methylcarbamoyl-4-hydroxy-1-naphthyl (405) 5-methoxy-6-N-ethylsulfamoyl- 1-naphthyl (406) 7-tetradecyloxy-1-naphthyl (407) 4- (4-methylphenoxy) -1-naphthyl (408) 6-N-methylsulfamoyl-1-naphthyl (409) 3- N, N-dimethylcarbamoyl-4-methoxy-1-naphthyl (410) 5-methoxy-6-N-benzylsulfamoyl 1-naphthyl (411) 3,6-di-N-phenylsulfamoyl-1-naphthyl (412) methyl (413) ethyl (414) butyl (415) octyl (416) dodecyl (417) 2-butoxy-2 -Ethoxyethyl (418) benzyl (419) 4-methoxybenzyl

(424) Methyl (425) Phenyl (426) Butyl

(430) methyl (431) ethyl (432) butyl (433) octyl (434) dodecyl (435) 2-butoxy-2-ethoxyethyl (436) benzyl (437) 4-methoxybenzyl

  In the present invention, a melamine polymer may be used as the compound having a 1,3,5-triazine ring. The melamine polymer is preferably synthesized by a polymerization reaction between a melamine compound represented by the following general formula (II) and a carbonyl compound.

In the above synthetic reaction scheme, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or a heterocyclic group.

  The alkyl group, alkenyl group, aryl group, heterocyclic group, and substituents thereof have the same meanings as the groups and substituents described in the general formula (I).

  The polymerization reaction between the melamine compound and the carbonyl compound is the same as the method for synthesizing a normal melamine resin (for example, melamine formaldehyde resin). Moreover, you may use a commercially available melamine polymer (melamine resin).

  The molecular weight of the melamine polymer is preferably 2,000 to 400,000. Specific examples of the repeating unit of the melamine polymer are shown below.

MP-1: R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ : CH ₂ OH
^{MP-2: R 13, R} 14, R 15, R 16: CH 2 OCH 3
^{MP-3: R 13, R} 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-4: R 13, R} 14, R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-5: R 13, R} 14, R 15, R 16: CH 2 NHCOCH = CH 2
^{MP-6: R 13, R} 14, R 15, R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-7: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 OCH 3
^{MP-8: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 OCH 3
^{MP-9: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 OCH 3
^{MP-10: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 OCH 3
^{MP-11: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 OCH 3
^{MP-12: R 13, R} 14, R 16: CH 2 OCH 3; R 15: CH 2 OH
^{MP-13: R 13, R} 16: CH 2 OCH 3; R 14, R 15: CH 2 OH
^{MP-14: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-i-C 4 H 9
^{MP-15: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-i-C 4 H 9
^{MP-16: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-17: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-i-C 4 H 9
^{MP-18: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-19: R 13, R} 14, R 16: CH 2 O-i-C 4 H 9; R 15: CH 2 OH
^{MP-20: R 13, R} 16: CH 2 O-i-C 4 H 9; R 14, R 15: CH 2 OH
MP-21: R ¹³ , R ¹⁴ , R ¹⁵ : CH ₂ OH; R ¹⁶ : CH _{2 On} -C ₄ H ₉
^{MP-22: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-23: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-24: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9
^{MP-25: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2O -n-C 4 H 9
^{MP-26: R 13, R} 14, R 16: CH 2 O-n-C 4 H 9; R 15: CH 2 OH
^{MP-27: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-28: R 13, R} 14: CH 2 OH; R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-29: R 13, R} 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-30: R 13, R} 16: CH 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-31: R 13: CH} 2 OH; R 14, R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-32: R 13: CH} 2 OH; R 14, R 16: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-33: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-34: R 13: CH} 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-35: R 13, R} 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-36: R 13, R} 16: CH 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-37: R 13: CH} 2 OCH 3; R 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-38: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH
^{MP-39: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C4H9; R 16: CH 2 NHCOCH = CH 2
^{MP-40: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-41: R 13: CH} 2 OH; R 14: CH 2 O-n-C 4 H 9; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-42: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-43: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-44: R 13: CH} 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2
^{MP-45: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-46: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-47: R 13: CH} 2 OH; R 14: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-48: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-49: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-50: R 13: CH} 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2

^{MP-51: R 13, R} 14, R 15, R 16: CH 2 OH
^{MP-52: R 13, R} 14, R 15, R 16: CH 2 OCH 3
^{MP-53: R 13, R} 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-54: R 13, R} 14, R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-55: R 13, R} 14, R 15, R 16: CH 2 NHCOCH = CH 2
^{MP-56: R 13, R} 14, R 15, R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-57: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 OCH 3
^{MP-58: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 OCH 3
^{MP-59: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 OCH 3
^{MP-60: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 OCH 3
^{MP-61: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 OCH 3
^{MP-62: R 13, R} 14, R 16: CH 2 OCH 3; R 15: CH 2 OH
^{MP-63: R 13, R} 16: CH 2 OCH 3; R 14, R 15: CH 2 OH
^{MP-64: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-i-C 4 H 9
^{MP-65: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-i-C 4 H 9
^{MP-66: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-67: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-i-C 4 H 9
^{MP-68: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-69: R 13, R} 14, R 16: CH 2 O-i-C 4 H 9; R 15: CH 2 OH
^{MP-70: R 13, R} 16: CH 2 O-i-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-71: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-72: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-73: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-74: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9
^{MP-75: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-76: R 13, R} 14, R 16: CH 2 O-n-C 4 H 9; R 15: CH 2 OH
^{MP-77: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-78: R 13, R} 14: CH 2 OH; R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-79: R 13, R} 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-80: R 13, R} 16: CH 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-81: R 13: CH} 2 OH; R 14, R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-82: R 13: CH} 2 OH; R 14, R 16: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-83: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-84: R 13: CH} 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-85: R 13, R} 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-86: R 13, R} 16: CH 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-87: R 13: CH} 2 OCH 3; R 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-88: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH
^{MP-89: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-90: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-91: R 13: CH} 2 OH; R 14: CH 2 O-n-C 4 H 9; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-92: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-93: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-94: R 13: CH} 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2
^{MP-95: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-96: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-97: R 13: CH} 2 OH; R 14: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-98: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-99: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-100: R 13: CH} 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2

^{MP-101: R 13, R} 14, R 15, R 16: CH 2 OH
^{MP-102: R 13, R} 14, R 15, R 16: CH 2 OCH 3
^{MP-103: R 13, R} 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-104: R 13, R} 14, R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-105: R 13, R} 14, R 15, R 16: CH 2 NHCOCH = CH 2
^{MP-106: R 13, R} 14, R 15, R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-107: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 OCH 3
^{MP-108: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 OCH 3
^{MP-109: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 OCH 3
^{MP-110: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 OCH 3
^{MP-111: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 OCH 3
^{MP-112: R 13, R} 14, R 16: CH 2 OCH 3; R 15: CH 2 OH
^{MP-113: R 13, R} 16: CH 2 OCH 3; R 14, R 15: CH 2 OH
^{MP-114: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-i-C 4 H 9
^{MP-115: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-i-C 4 H 9
^{MP-116: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-117: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-i-C 4 H 9
^{MP-118: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-119: R 13, R} 14, R 16: CH 2 O-i-C 4 H 9; R 15: CH 2 OH
^{MP-120: R 13, R} 16: CH 2 O-i-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-121: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-122: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-123: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-124: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9
^{MP-125: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-126: R 13, R} 14, R 16: CH 2 O-n-C 4 H 9; R 15: CH 2 OH
^{MP-127: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-128: R 13, R} 14: CH 2 OH; R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-129: R 13, R} 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-130: R 13, R} 16: CH 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-131: R 13: CH} 2 OH; R 14, R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-132: R 13: CH} 2 OH; R 14, R 16: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-133: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-134: R 13: CH} 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-135: R 13, R} 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-136: R 13, R} 16: CH 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-137: R 13: CH} 2 OCH 3; R 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-138: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH
^{MP-139: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-140: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-141: R 13: CH} 2 OH; R 14: CH 2 O-n-C 4 H 9; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-142: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-143: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-144: R 13: CH} 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2
^{MP-145: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-146: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-147: R 13: CH} 2 OH; R 14: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-148: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-149: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-150: R 13: CH} 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2

^{MP-151: R 13, R} 14, R 15, R 16: CH 2 OH
^{MP-152: R 13, R} 14, R 15, R 16: CH 2 OCH 3
^{MP-153: R 13, R} 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-154: R 13, R} 14, R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-155: R 13, R} 14, R 15, R 16: CH 2 NHCOCH = CH 2
^{MP-156: R 13, R} 14, R 15, R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-157: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 OCH 3
^{MP-158: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 OCH 3
^{MP-159: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 OCH 3
^{MP-160: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 OCH 3
^{MP-161: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 OCH 3
^{MP-162: R 13, R} 14, R 16: CH 2 OCH 3; R 15: CH 2 OH
^{MP-163: R 13, R} 16: CH 2 OCH 3; R 14, R 15: CH 2 OH
^{MP-164: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-i-C 4 H 9
^{MP-165: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-i-C 4 H 9
^{MP-166: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-167: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-i-C 4 H 9
^{MP-168: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-i-C 4 H 9
^{MP-169: R 13, R} 14, R 16: CH 2 O-i-C 4 H 9; R 15: CH 2 OH
^{MP-170: R 13, R} 16: CH 2 O-i-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-171: R 13, R} 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-172: R 13, R} 14, R 16: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-173: R 13, R} 14: CH 2 OH; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-174: R 13, R} 16: CH 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9
^{MP-175: R 13: CH} 2 OH; R 14, R 15, R 16: CH 2 O-n-C 4 H 9
MP-176: R ¹³ , R ¹⁴ , R ¹⁶ : CH _{2 On} -C ₄ H ₉ ; R ¹⁵ : CH ₂ OH
^{MP-177: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14, R 15: CH 2 OH
^{MP-178: R 13, R} 14: CH 2 OH; R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-179: R 13, R} 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-180: R 13, R} 16: CH 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-181: R 13: CH} 2 OH; R 14, R 15: CH 2 OCH 3; R 16: CH 2 O-n-C 4 H 9
^{MP-182: R 13: CH} 2 OH; R 14, R 16: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9
^{MP-183: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15, R 16: CH 2 O-n-C 4 H 9
^{MP-184: R 13: CH} 2 OH; R 14, R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 OCH 3
^{MP-185: R 13, R} 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2O -n-C 4 H 9
^{MP-186: R 13, R} 16: CH 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9
^{MP-187: R 13: CH} 2 OCH 3; R 14, R 15: CH 2 OH; R 16: CH 2 O-n-C 4 H 9
^{MP-188: R 13, R} 16: CH 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH
^{MP-189: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-190: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-191: R 13: CH} 2 OH; R 14: CH 2 O-n-C 4 H 9; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-192: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 O-n-C 4 H 9; R 16: CH 2 NHCOCH = CH 2
^{MP-193: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 O-n-C 4 H 9
^{MP-194: R 13: CH} 2 O-n-C 4 H 9; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2
^{MP-195: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-196: R 13: CH} 2 OH; R 14: CH 2 OCH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-197: R 13: CH} 2 OH; R 14: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 OCH 3
^{MP-198: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 16: CH 2 NHCOCH = CH 2
^{MP-199: R 13: CH} 2 OCH 3; R 14: CH 2 OH; R 15: CH 2 NHCOCH = CH 2; R 16: CH 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3
^{MP-200: R 13: CH} 2 NHCO (CH 2) 7 CH = CH (CH 2) 7 CH 3; R 14: CH 2 OCH 3; R 15: CH 2 OH; R 16: CH 2 NHCOCH = CH 2
In the present invention, a copolymer obtained by combining two or more of the above repeating units may be used. Two or more homopolymers or copolymers may be used in combination.

  Moreover, you may use together the compound which has a 2 or more types of 1,3,5- triazine ring. Two or more kinds of discotic compounds (for example, a compound having a 1,3,5-triazine ring and a compound having a porphyrin skeleton) may be used in combination.

<Dope solvent>
Organic solvents useful for forming a dope that dissolves the cellulose ester include chlorinated organic solvents and non-chlorinated organic solvents. Methylene chloride (methylene chloride) can be mentioned as a chlorinated organic solvent, and it is suitable for dissolving cellulose esters such as cellulose acetate and cellulose acetate propionate. In addition, a non-chlorine organic solvent can be used.

  Non-chlorine organic solvents include methyl acetate, ethyl acetate, amyl acetate, acetone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2, 2,3,3-tetrafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, 1,1, Examples include 1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, and the like.

  When these organic solvents are used for cellulose esters, a dissolution method at room temperature can be used, but an insoluble material can be obtained by using a dissolution method such as a high-temperature dissolution method, a cooling dissolution method, or a high-pressure dissolution method. Can be reduced, which is preferable. Although methylene chloride can be used, methyl acetate, ethyl acetate, and acetone are also preferably used. Particularly preferred is methyl acetate.

  An organic solvent having good solubility in the cellulose ester used in the present invention is called a good solvent, and shows a main effect in dissolution, and an organic solvent used in a large amount among them is a main organic solvent or a main organic solvent. That's it. Here, the good solvent is a solvent that exhibits a solubility of 5 g or more in 100 g of the solvent at 25 ° C.

  The dope used in the present invention preferably contains 1 to 40% by mass of an alcohol having 1 to 4 carbon atoms in addition to the organic solvent. They are used as gelling solvents to cast the dope onto a metal support and then the solvent begins to evaporate, and the alcohol becomes higher and the web gels, making it easier to peel from the metal support with the web on top . Moreover, when these ratios are small, there is also a role of promoting the dissolution of the cellulose ester of the non-chlorine organic solvent. Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol and the like. Of these, ethanol is preferred because it has excellent dope stability, has a relatively low boiling point, good drying properties, and no toxicity. These organic solvents alone are poorly soluble or insoluble in cellulose esters and fall into the category of poor solvents. The poor solvent is assumed to show solubility of less than 5 g of cellulose ester in 100 g of solvent at 25 ° C.

  From the viewpoint of improving the film surface quality, the cellulose ester concentration in the dope is preferably adjusted to 15 to 40% by mass, and the dope viscosity is preferably adjusted to a range of 10 to 50 Pa · s.

  Dyes, matting agents, etc. may also be added. These compounds may be added together with the cellulose ester or the solvent during the preparation of the cellulose ester solution, or may be added during or after the solution preparation.

<Plasticizer>
The film A and / or film B used for the polarizing plate of the present invention is added with a compound known as a so-called plasticizer for the purpose of improving mechanical properties, imparting flexibility, imparting water absorption resistance, and reducing water vapor transmission rate. For example, phosphate ester derivatives and carboxylic acid ester derivatives are preferably used. Further, a polymer obtained by polymerizing an ethylenically unsaturated monomer having a weight average molecular weight of 500 to 10,000 described in JP-A-2003-12859, an acrylic polymer, an acrylic polymer having an aromatic ring in the side chain, or cyclohexyl An acrylic polymer having a group in the side chain is also preferably used.

  Examples of phosphate ester derivatives include triphenyl phosphate, tricresyl phosphate, phenyl diphenyl phosphate, and the like.

  Examples of the carboxylic acid ester derivatives include phthalic acid esters and citric acid esters. Examples of the phthalic acid ester derivatives include dimethyl phthalate, diethyl phthalate, dicyclohexyl phthalate, dioctyl phthalate, and diethyl hexyl phthalate. Can include acetyltriethyl citrate and acetyltributyl citrate.

  In addition, butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, triacetin, trimethylolpropane tribenzoate, and the like can also be mentioned. Alkylphthalylalkyl glycolates are also preferably used for this purpose. The alkyl in the alkylphthalylalkyl glycolate is an alkyl group having 1 to 8 carbon atoms. Examples of alkyl phthalyl alkyl glycolates include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl glycolate, Ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, propyl phthalyl ethyl glycolate, methyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl Phthalyl ethyl glycolate, propyl phthalyl butyl glycolate, butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl Collate, octyl phthalyl methyl glycolate, octyl phthalyl ethyl glycolate and the like can be mentioned, methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, Octyl phthalyl octyl glycolate is preferable, and ethyl phthalyl ethyl glycolate is particularly preferably used. Moreover, you may use these alkylphthalyl alkyl glycolates etc. in mixture of 2 or more types.

  The addition amount of these compounds is preferably 0.5% by mass to less than 20% by mass, more preferably 1% by mass to 11% by mass with respect to the resin in which the plasticizer constitutes the film. It is in the range of less than. The amount of these compounds added can be adjusted from the standpoints of achieving the desired effect and suppressing bleed out from the film. These plasticizers preferably have a vapor pressure of 1333 Pa or less at 200 ° C. in order to suppress bleed out.

<Deterioration inhibitor>
A degradation inhibitor (eg, antioxidant, peroxide decomposer, radical inhibitor, metal deactivator, acid scavenger, amine, etc.) may be added to the polymer film of the present invention. The deterioration preventing agents are described in JP-A-3-199201, JP-A-51907073, JP-A-5-194789, JP-A-5-271471, and JP-A-6-107854. Examples of particularly preferred deterioration inhibitors include butylated hydroxytoluene (BHT) and tribenzylamine (TBA).

<Ultraviolet absorber>
The ultraviolet absorber is excellent in the ability to absorb ultraviolet rays having a wavelength of 370 nm or less from the viewpoint of preventing deterioration of the polarizer and the display device with respect to ultraviolet rays, and has little absorption of visible light having a wavelength of 400 nm or more from the viewpoint of liquid crystal display properties. Those are preferred. Examples of the ultraviolet absorber used in the present invention include oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, and the like, but benzophenone compounds And benzotriazole-based compounds with little coloring are preferred. Moreover, you may use the ultraviolet absorber of Unexamined-Japanese-Patent No. 10-182621, Unexamined-Japanese-Patent No. 8-337574, and the polymeric ultraviolet absorber of Unexamined-Japanese-Patent No. 6-148430.

  Specific examples of useful benzotriazole ultraviolet absorbers include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl). ) Benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl)- 5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′-(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl) -5′-methylphenyl) benzotriazole, 2,2-methylenebis ( 4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol), 2- (2'-hydro Cis-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -6- (linear and side chain dodecyl) -4-methylphenol Octyl-3- [3-tert-butyl-4-hydroxy-5- (chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy Examples include, but are not limited to, a mixture of -5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate.

  As commercially available products, TINUVIN 109, TINUVIN 171 and TINUVIN 326 (all manufactured by Ciba Specialty Chemicals) can be preferably used.

  Specific examples of benzophenone compounds include 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy- 5-benzoylphenylmethane) and the like, but are not limited thereto.

  The addition method to the dope of the ultraviolet absorber, the deterioration inhibitor, and the retardation improver can be used without limitation as long as the compound to be added is soluble, but in the present invention, for example, methylene chloride in the ultraviolet absorber, Dissolve in a good solvent for cellulose esters such as methyl acetate and dioxolane, or in a mixed organic solvent of a good solvent and a poor solvent such as lower aliphatic alcohols (methanol, ethanol, propanol, butanol, etc.) A method of mixing with an ester solution to form a dope is preferable. A deterioration inhibitor and a retardation improver can be similarly prepared as a mixed dope according to the purpose together with the ultraviolet absorber. At this time, it is preferable that the dope solvent composition and the solvent composition of the solution to be added are as close as possible or close to each other.

<Matting agent>
In this invention, it can make it easy to convey and wind up by containing a mat agent in a cellulose-ester film. The matting agent is preferably as fine as possible. Examples of the fine particles include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, kaolin, talc, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, Examples thereof include inorganic fine particles such as magnesium silicate and calcium phosphate, and crosslinked polymer fine particles. Among these, silicon dioxide is preferable because it can reduce the haze of the film. In many cases, fine particles such as silicon dioxide are surface-treated with an organic material, but such particles are preferable because they can reduce the haze of the film.

  Preferred organic substances for the surface treatment include halosilanes, alkoxysilanes, silazane, siloxane and the like. The larger the average particle size of the fine particles, the greater the sliding effect, and the smaller the average particle size, the better the transparency. The average particle size of the secondary particles of the fine particles is in the range of 0.05 to 1.0 μm. The average particle size of secondary particles of the fine particles is preferably 5 to 50 nm, more preferably 7 to 14 nm. These fine particles are preferably used in the cellulose ester film in order to generate irregularities of 0.01 to 1.0 μm on the surface of the cellulose ester film. The content of the fine particles in the cellulose ester is preferably 0.005 to 0.3% by mass with respect to the cellulose ester.

  Examples of the fine particles of silicon dioxide include Aerosil 200, 200V, 300, R972, R972V, R974, R202, R812, OX50, TT600 manufactured by Nippon Aerosil Co., Ltd., preferably Aerosil 200V, R972. , R972V, R974, R202, R812. Two or more kinds of these fine particles may be used in combination. When using 2 or more types together, it can mix and use in arbitrary ratios. In this case, fine particles having different average particle sizes and materials, for example, Aerosil 200V and R972V can be used in a mass ratio of 0.1: 99.9 to 99.9: 0.1.

  (2) Casting step: Casting a dope on a metal support such as an endless metal belt, such as a stainless steel belt or a rotating metal drum, which sends the dope through a pressurized metering gear pump to a pressure die and transfers it indefinitely. This is a step of casting a dope from a pressure die at a position. The surface of the metal support is a mirror surface. Other casting methods include a doctor blade method in which the film thickness of the cast dope film is adjusted with a blade, or a reverse roll coater method in which the film is adjusted with a reverse rotating roll. A pressure die that can be prepared and facilitates uniform film thickness is preferred. Examples of the pressure die include a coat hanger die and a T die, and any of them is preferably used. In order to increase the film forming speed, two or more pressure dies may be provided on the metal support, and the dope amount may be divided and stacked.

  (3) Solvent evaporation step: The web (the dope film after the dope is cast on the metal support is referred to as the web) is heated on the metal support, and the web can be peeled from the metal support. This is a step of evaporating the solvent. In order to evaporate the solvent, there are a method of blowing air from the web side and / or a method of transferring heat from the back side of the metal support by a liquid, a method of transferring heat from the front and back by radiant heat, and the like. Is preferable in terms of drying efficiency. A method of combining them is also preferable.

  In order to increase the film forming speed, a method of increasing the web temperature on the metal support is effective. However, since excessive heat supply causes foaming from the inside of the web due to the solvent contained in the web, a preferable drying rate is defined by the composition of the web. A method of casting on a belt-like metal support is also preferably used in order to increase the film forming speed. When casting is performed using a belt-like support, the casting speed can be increased by increasing the belt length. However, increasing the belt length promotes deflection due to the belt's own weight. In order to cause vibration during film formation and make the film thickness non-uniform during casting, the belt length is preferably 40 to 120 m.

  (4) Peeling step: This is a step of peeling the web where the solvent has evaporated on the metal support at the peeling position. The peeled web is sent to the next process. If the residual solvent amount of the web at the time of peeling is too large, peeling is difficult, or conversely, if it is peeled off after sufficiently drying on the metal support, a part of the web is peeled off.

  There is a gel casting method (gel casting) as a method for increasing the film forming speed (the film forming speed can be increased because the film is peeled off while the residual solvent amount is as large as possible).

  This method includes a method of adding a poor solvent for the cellulose ester in the dope and casting the dope and then gelling, a method of reducing the temperature of the metal support and gelling. By gelling on the metal support and increasing the strength of the film at the time of peeling, the speed of film formation can be increased by speeding up the peeling.

  In this invention, it is preferable to adjust the temperature in the peeling position on this metal support body to 10-40 degreeC, More preferably, it is adjusting to 15-30 degreeC. Moreover, it is preferable that the quantity of the web in a peeling position shall be 30-120 mass%. In the present invention, the residual solvent amount can be expressed by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

  When the film is formed on the belt-like support, the increase in speed promotes the above-described belt vibration. Considering the amount of residual solvent and belt length at the time of peeling, the film forming speed is preferably 10 to 120 m / min, more preferably 15 to 60 m / min.

  In the present invention, the residual solvent amount relative to the entire width of the web may be referred to as an average residual solvent amount or a residual solvent amount at the center, and may also refer to a local residual solvent amount such as a residual solvent amount at both ends of the web. is there.

  (5) Drying step: In general, after peeling, generally, the web is transferred using a drying device and / or a tenter device that clips and conveys the both ends of the web with a clip. dry. As a drying means, hot air is generally blown on both sides of the web, but there is also a means for heating by applying a microwave instead of the wind. Too much drying tends to impair the flatness of the finished film. Throughout, the drying temperature is usually in the range of 30 to 250 ° C. The drying temperature, the amount of drying air, and the drying time differ depending on the solvent used, and the drying conditions may be appropriately selected according to the type and combination of the solvents used.

  In the present invention, the process of transporting the cast film to the tenter part after peeling off the cast film may be referred to as “process D0”. In step D0, it is preferable to control the temperature for the purpose of controlling the amount of residual solvent in the film during stretching. Although depending on the amount of residual solvent in the film in step D0, stretching in the transport direction (hereinafter referred to as the longitudinal direction) hardly occurs, and 20 to 80 ° C. is preferable with the intention of adjusting the residual solvent amount, and more preferably 20 to 20 ° C. It is 70 degreeC, Most preferably, it is 20-50 degreeC.

  In the process D0, the fact that the film atmosphere temperature distribution is small in the film plane and in the direction perpendicular to the film conveyance (hereinafter referred to as the width direction) has a preferable range from the viewpoint of improving the film uniformity. The temperature distribution in the step D0 is preferably within ± 5 ° C., more preferably within ± 2 ° C., and most preferably within ± 1 ° C.

  As the film transport tension in the step D0, there are preferable conditions as shown below from the viewpoint of preventing peeling from the support and elongation in the transport direction in the step D0.

  The film transport tension in the step D0 is affected by the physical properties of the dope, at the time of peeling and the residual solvent amount in the step D0, the temperature in the step D0, etc., but is preferably 30 to 300 N / m, more preferably 57 to 284 N. / M, particularly preferably 57 to 170 N / m. For the purpose of preventing the film from stretching in the transport direction in step D0, it is preferable to provide a tension cut roll. A preferable range of the ratio of the good solvent and the poor solvent in the step D0 is defined in terms of preventing elongation with respect to the film conveyance. As the poor solvent mass / (good solvent mass + poor solvent mass) × 100 (%) at the end point of the step D0, a range of 95% by mass to 15% by mass is preferable, and more preferably 95% by mass to 25% by mass. Yes, and particularly preferably 95% by mass to 30% by mass.

(6) Stretching Step An example of the stretching step (also referred to as a tenter step) according to the present invention will be described with reference to FIG.

  In FIG. 2, step A is a step of gripping the film transported from the film transport step D0 (not shown). In the next step B, the film is wide at a stretching angle as shown in FIG. The film is stretched in the direction (direction perpendicular to the traveling direction of the film), and in step C, the stretching is completed and the film is conveyed while being held.

  It is preferable to provide a slitter for cutting off the end in the film width direction after the film is peeled off and before the start of the process B and / or immediately after the process C. In particular, it is preferable to provide a slitter that cuts off the film edge immediately before the start of the step A. When the same stretching is performed in the width direction, the effect of the former improving the orientation angle distribution more is obtained, especially when the film edge is cut off before the start of Step B and the film edge is not cut off. It is done.

  This is considered to be an effect of suppressing unintended stretching in the longitudinal direction from the peeling with a relatively large amount of residual solvent to the width stretching step B.

  In the tenter process, it is also preferable to intentionally create compartments with different temperatures in order to improve the orientation angle distribution. It is also preferable to provide a neutral zone between different temperature zones so that the zones do not interfere with each other.

  The stretching operation may be performed in multiple stages, or biaxial stretching may be performed in the casting direction and the width direction. Also, when biaxial stretching is performed, simultaneous biaxial stretching may be performed or may be performed stepwise. In this case, stepwise means that, for example, stretching in different stretching directions can be sequentially performed, stretching in the same direction is divided into multiple stages, and stretching in different directions is added to any one of the stages. Is also possible. That is, for example, the following stretching steps are possible.

-Stretch in the casting direction-Stretch in the width direction-Stretch in the casting direction-Stretch in the casting direction-Stretch in the width direction-Stretch in the width direction-Stretch in the casting direction-Stretching in the casting direction In this case The term “when stretching is completed” refers to the time of stretching at the final stage of the stretching operation in which an in-plane retardation (Ro) value per dry film thickness of 100 μm is 15 nm or more. That is, when a small amount of stretching operation associated with normal film conveyance or a substantial stretching operation by regulating drying shrinkage by maintaining the width does not contribute to the expression of the R ₀ value, the residual solvent amount of the present invention. This does not apply to “stretching completion” when stipulating.

  Further, the “stretch direction” in the present invention is usually used to mean a direction in which a stretching stress is directly applied when performing a stretching operation, but in the case of being biaxially stretched in multiple stages, In some cases, it is used in the sense of the one having a higher draw ratio (that is, the direction usually serving as the slow axis). In particular, in the case of the expression relating to the dimensional change rate, the expression “stretch direction” is mainly used in the latter sense. The residual solvent amount is expressed by the above formula.

  In order to improve the dimensional stability under the conditions of 80 ° C. and 90% RH by performing the stretching operation of the polymer film, it is preferable to perform the stretching operation in the presence of a residual solvent and under heating conditions. The inventors of the present invention have dimensional stability at 80 ° C. and 90% RH in the in-plane direction orthogonal to the stretching direction (the width direction when the width at the time of casting finally becomes the slow axis) and the stretching direction. We found that the following tendencies exist.

  That is, the dimensional stability at 80 ° C. and 90% RH in the stretching direction has a relatively small dependence on the stretching temperature and a relatively large residual solvent dependence. On the other hand, the dimensional stability under the same conditions in the in-plane direction orthogonal to the stretching direction has a relatively large dependence on the stretching temperature and a small dependence on the residual solvent. Here, the stretching temperature refers to the environmental temperature during the stretching operation, and the film temperature at the end of stretching is usually raised to substantially the same as the stretching temperature. Further, when the temperature and residual solvent conditions are optimized in each direction, the effect of improving the dimensional stability of 80 ° C. and 90% RH is that the effect on the stretching direction is in the in-plane direction perpendicular to the stretching direction. It has been found to be superior to the effect.

  Specifically, for example, a cellulose ester film having a film thickness of about 80 μm with a Ro value of 40 to 50 nm will be described. In in-line stretching in which stretching is continuously performed after casting, the stretching temperature is 120 ° C. or higher, and the amount of residual solvent Is 7% by mass or more at the end of stretching, the rate of dimensional change after 100 hours under the conditions of 80 ° C. and 90% RH in the casting direction (MD direction) is excellent within ± 1.0%. A film is obtained. In addition, when the stretching temperature is 110 ° C. or more and the residual solvent amount is 12% by mass or more at the end of stretching, the dimensional change rate under the same conditions in the width direction (TD direction) is within ± 0.5%. Can be obtained. Further, by setting the stretching temperature to 100 ° C. or more and the residual solvent amount to 12% by mass or more at the end of stretching, the dimensional change rate after 100 hours at 80 ° C. and 90% RH is within ± 1.5% in the MD direction. , A film within ± 1.0% in the TD direction can be obtained.

  More preferably, by setting the stretching conditions to a stretching temperature of 120 ° C. or more and the residual solvent amount to 7% by mass or more at the end of stretching, the dimensional change rate under these conditions is ± 1.0% in the MD direction and 0 in the TD direction. A film of less than 5% can be obtained. More preferably, when the stretching temperature is 130 ° C. or more and the residual solvent amount is 12% by mass or more at the end of stretching, the dimensional change rate under the conditions is 0.7% in the MD direction and within ± 0.2 in the TD direction. It is possible to obtain a film.

  In the tenter process, it is preferable that the relationship Ma> Mc is satisfied, where the good solvent concentrations in the processes A, B, and C are Ma, Mb, and Mc, respectively. Moreover, it is preferable to satisfy the relationship of Mb> Mc.

  There is no particular limitation on the residual solvent in the film at the end points of Steps A, B, and C in the tenter step, but there are preferred good solvent and poor solvent ratios. Each residual poor solvent mass / (residual good solvent mass + residual poor solvent mass) × 100 (%) at the end of Steps A, B, and C is preferably in the range of 95% by mass to 15% by mass. Furthermore, 95 mass%-25 mass% are preferable, and the range of 95 mass%-30 mass% is the most preferable. Moreover, each residual poor solvent mass / (residual good solvent mass + residual poor solvent mass) × 100 (%) at the end of Steps A, B, and C may be the same or different.

  When the film is stretched in the width direction, it is well known that the optical slow axis distribution (hereinafter, orientation angle distribution) deteriorates in the width direction of the film. Since width stretching is performed with the Rth and Ro values at a constant ratio and with a good orientation angle distribution, there is a preferred film temperature relative relationship in steps A, B, and C. When the film temperatures at the end points of Steps A, B, and C are Ta ° C., Tb ° C., and Tc ° C., respectively, it is preferable that Ta ≦ Tb−10. Moreover, it is preferable that Tc ≦ Tb. More preferably, Ta ≦ Tb−10 and Tc ≦ Tb.

  The film heating rate in the step B is preferably in the range of 0.5 to 10 ° C./s in order to improve the orientation angle distribution.

  The stretching time in step B is preferably a short time in order to reduce the dimensional change rate under the conditions of 80 ° C. and 90% RH. However, the minimum required stretching time range is defined from the viewpoint of film uniformity. Specifically, the range is preferably 1 to 10 seconds, and more preferably 4 to 10 seconds.

In the tenter process, the heat transfer coefficient may be constant or changed. The heat transfer coefficient preferably has a heat transfer coefficient in the range of 41.9 to 419 × 10 ³ J / m ² hr. More preferably, in the range of ^{41.9~209.5 × 10 3 J / m 2} hr, and most preferably a range of ^{41.9~126 × 10 3 J / m 2} hr.

  In order to improve the dimensional stability under the conditions of 80 ° C. and 90% RH, the stretching speed in the width direction in the step B may be constant or may be changed. The stretching speed is preferably 50 to 500% / min, more preferably 100 to 400% / min, and most preferably 200 to 300% / min.

  In the tenter process, the fact that the film atmosphere temperature distribution is small has a preferable range from the viewpoint of enhancing the uniformity of the film. The temperature distribution in the tenter process is preferably within ± 5 ° C, more preferably within ± 2 ° C, and most preferably within ± 1 ° C. By reducing the temperature distribution, it can be expected that the temperature distribution in the width of the film is also reduced.

  In step C, it is preferable to relax in a direction perpendicular to the film conveyance direction in order to suppress dimensional changes. Specifically, it is preferable to adjust the film width so that it is in the range of 95 to 99.5% with respect to the film width of the previous step.

  After the treatment in the tenter process, it is preferable to further provide a post-drying process (hereinafter referred to as process D1). In order to refine the optical properties imparted to the cellulose ester film in the tenter process and to dry it, it is preferable to perform a heat treatment in the temperature range of 50 to 140 ° C. More preferably, it is the range of 80-140 degreeC, Most preferably, it is the range of 80-130 degreeC.

It is preferable to perform heat treatment at a heat transfer coefficient of 20.9 to 126 × 10 ³ J / m ² hr for the purpose of refining the optical properties imparted to the cellulose ester film in the tenter process and drying. More preferably, in the range of ^{41.9~126 × 10 3 J / m 2} hr, and most preferably in the range of ^{41.9~83.7 × 10 3 J / m 2} hr.

  In the step D1, the fact that the film atmosphere temperature distribution is small in the width film plane and perpendicular to the film conveyance has a preferable range from the viewpoint of improving the uniformity of the film. The temperature distribution in the tenter process is preferably within ± 5 ° C, more preferably within ± 2 ° C, and most preferably within ± 1 ° C.

  The film transport tension in the step D1 has preferable conditions in order to prevent the film from stretching in the transport direction. The film transport tension in the step D1 is affected by the physical properties of the dope, the peeling and the residual solvent amount in the step D0, the temperature in the step D1, etc., but is preferably 120 to 200 N / m, and 140 to 200 N / m. Further preferred. 140 to 160 N / m is most preferable.

  In order to prevent the film from stretching in the transport direction in step D1, it is preferable to provide a tension cut roll. After drying, it is preferable to provide a slitter and cut off the end portion before winding to obtain a good winding shape.

  In the polarizing plate of the present invention, in order to impart an optical retardation to the film for improving display characteristics, the cellulose ester film can be stretched in the width direction to control the retardation of the cellulose ester film. preferable.

  In order to achieve the object of the present invention, specifically, the film A used for the polarizing plate of the present invention preferably has a film thickness of 20 μm or more and 100 μm or less prepared by a casting film forming method, which is effective for the effect of the present invention. In addition, this is derived from the viewpoint of both physical strength of the film and production. The film thickness of the film A is more preferably in the range of 30 μm or more and 85 μm or less.

  The film B used for the polarizing plate of the present invention is preferably a film thickness of 30 μm or more and 150 μm or less produced by a casting film forming method, which is compatible with the physical strength of the film and the production surface in addition to the effects of the present invention. Derived from the perspective. The thickness of the film B is more preferably in the range of 40 μm to 120 μm.

<Polarizer>
The polarizing plate of the present invention can be produced by using a film obtained by stretching polyvinyl alcohol doped with iodine as a polarizer, and laminating with a configuration of film A / polarizer / film B.

  Moreover, although the film A and / or the film B may be attached to the polarizing plate other than the present invention in order to obtain the effects of the present invention, the protective film for the polarizing plate is preferably the film A and the film B.

  The film B used for the polarizing plate of this invention is demonstrated.

  When stretching the film in the width direction, it is important to stretch the film while controlling the orientation angle distribution in the width direction within a certain range. This can express the object of the present invention more effectively by keeping the orientation angle indicated by the slow axis of the film B used in the present invention within a certain range.

  It is preferable in mass production of a polarizing plate that the present invention is a long roll polarizing plate. This is preferable because the polarizer, the film A, and the film B are each in the form of a long roll, and thus can be directly applied to the production of the polarizing plate of the present invention in a known polarizing plate production process.

  The transmission axis of the long roll polarizer is preferably orthogonal to the transport direction from the viewpoint of mass production of the long roll polarizing plate. This is because when the slow axis of the long film B is orthogonal to the transport direction, it can coincide with the transmission axis direction of the long roll polarizer.

  Here, the orientation angle represents the direction of the slow axis in the plane of the cellulose ester film (angle relative to the width direction during casting film formation), and the orientation angle was measured by an automatic birefringence meter KOBRA-21ADH ( (Oji measuring instrument) can be used.

  At any measurement point where the orientation angle is in the width direction, it is preferably within ± 2 ° from the average orientation angle of all the measurement points, more preferably ± 1 °, and most preferably ± 0.5 °.

  The in-plane retardation (Ro) distribution of the cellulose ester film is preferably adjusted to 5% or less, more preferably 2% or less, and particularly preferably 1.5% or less. The retardation (Rth) 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.

  The numerical value of the retardation distribution is expressed by a variation coefficient (CV) of the retardation obtained by measuring the retardation at 1 cm intervals in the width direction of the obtained film. About the measurement method of the numerical value of the retardation and its distribution, for example, the in-plane retardation and the thickness direction retardation are obtained by the standard deviation by the (n-1) method, the coefficient of variation (CV) shown below is obtained, and the index And In the measurement, n can be calculated by setting to 130 to 140.

Coefficient of variation (CV) = standard deviation / retardation average value In the film A and film B used in the polarizing plate of the present invention, it is preferable that the variation in retardation distribution is small, and particularly when the present invention is used in a liquid crystal display device. The retardation distribution fluctuation of the film B is preferably small from the viewpoint of preventing color unevenness and the like.

The film B used for the polarizing plate of the present invention may have retardation wavelength dispersion, and when used in a display device, particularly a liquid crystal display element, the wavelength dispersion is appropriately selected in order to improve display quality. You can choose. Here, in the film B, the in-plane retardation R _{450 at 450} nm and the in-plane retardation at ₆₅₀ nm are defined as R ₆₅₀ similarly to the measured value Ro at 590 nm.

In the present invention, when the display device is used for MVA described later, the wavelength dispersion of the in-plane retardation of the film B is preferably 0.7 <R ₄₅₀ / R ₀ <1.0, 1.0 <R ₆₅₀ / R ₀ <1.5. More preferably, 0.7 <R ₄₅₀ / R ₀ <0.95, 1.01 <R ₆₅₀ / R ₀ <1.2, and particularly preferably 0.8 <R ₄₅₀ / R ₀ <0.93. 1.02 <R ₆₅₀ / R ₀ <1.1 can be selected in order to exert an effective effect on display color reproducibility.

  The film A and / or film B used as a polarizing plate of a display device, particularly a liquid crystal display device, is required to have high transmittance and ultraviolet absorption performance in order to obtain bright display characteristics and to achieve the object of the present invention. The transmittance of these films is preferably from 85% to 100%, more preferably from 90% to 100%, and more preferably from 92% to 100% after the film is formed by combining the above additives and dried. Most preferred. The 400 nm transmittance is preferably 40% to 100%, more preferably 50% to 100%, and most preferably 60% to 100%. The transmittance at 380 nm is preferably 0% to 10%, more preferably 0% to 5%, and most preferably 0% to 3%.

  Film A and / or film B preferably have high transparency, and preferably have a low haze value as well as high transmittance. The haze value is preferably 2% or less, more preferably 1.5% or less, and most preferably 1% or less. The same applies to a film stretched in the width direction during production.

The moisture permeability is defined as a value that can be measured by the method described in JIS Z 0208. Moisture permeability of the film A and / or film B, 25 ° C., is preferably 10 to 250 g / m ² · 24 hours under 90% RH environment, further to be 20 to 200 g / m ² · 24 hours Preferably, it is 50 to 180 g / m ² · 24 hours.

  When two polarizing plates of the present invention are used for a display device, particularly when the display device is a liquid crystal display device, two polarizing plates are disposed on both sides of the liquid crystal cell. At this time, the two polarizing plates may be the same or different, and an apparatus using the polarizing plate of the present invention on at least one side can express the object effect of the invention, and more effectively sandwich the two. The arrangement is shown in detail in FIG. FIG. 3 is a schematic diagram showing the configuration of the display device of the present invention. When two polarizing plates are respectively used as polarizing plate 1 (film A1 / polarizer / film B1) and polarizing plate 2 (film B2 / polarizer / film A2), the configuration viewed from the cross-sectional side of the display device is the polarizing plate. 1 (film A1 / polarizer / film B1) / liquid crystal cell / polarizing plate 2 (film B2 / polarizer / film A2), and the arrangement of observation from the vertical direction of the surface of the display device is two sheets. The transmission axes of the polarizing plates are substantially orthogonal, the films B1 and B2 are substantially the same film, and the slow axes of the films B1 and B2 are substantially parallel to the transmission axes of adjacent polarizers. It can function efficiently for the purpose of improving the display quality of the polarizing plate of the present invention.

  Here, the film A1 and the film A2 are in the range of the film A, and both may be the same or different. Moreover, the film B1 and the film B2 are in the range of the film B, and both may be the same or different, and are preferably the same film.

<Display device>
The display device can be used for a liquid crystal display device, and in particular, the effect of the present invention can be further exerted when used for a multi-domain liquid crystal display device, more preferably a multi-domain liquid crystal display device by a birefringence mode.

  Multi-domaining is also suitable for improving the symmetry of image display, and various methods have been reported "Okita, Yamauchi: Liquid Crystal, 6 (3), 303 (2002)". The liquid crystal display cell is also shown in “Yamada, Yamabara: Liquid Crystal, 7 (2), 184 (2003)”, but is not limited thereto.

  The polarizing plate of the present invention includes an MVA (Multi-domain Vertical Alignment) mode represented by a vertical alignment mode, in particular, an MVA mode divided into four, a known PVA (Patterned Vertical Alignment) mode and an electrode multi-domained by an electrode arrangement. It can be effectively used in a CPA (Continuous Pinwheel Alignment) mode in which arrangement and chiral ability are fused. In addition, a proposal of an optically biaxial film in the adaptation to the OCB (Optical Compensated Bend) mode has been disclosed, and “T. Miyashita, T. Uchida: J. SID, 3 (1), 29 ( 1995) ", the polarizing plate of the present invention can also exhibit the effect of the present invention in display quality. If the effect of this invention can be expressed by using the polarizing plate of this invention, arrangement | positioning of a liquid crystal mode and a polarizing plate will not be limited.

  The display quality of the display cell is preferably symmetrical with respect to human observation. Therefore, when the display cell is a liquid crystal display cell, the domains can be multiplied substantially giving priority to the symmetry on the observation side. A known method can be used to divide the domain, and can be determined by taking into account the properties of the known liquid crystal mode by a two-division method, more preferably a four-division method.

  The liquid crystal display device is being applied to devices for colorization and moving image display, and the display quality in the present invention is that the display of moving images is less fatigued and faithful due to improved contrast and improved resistance of the polarizing plate. It becomes possible. For example, in a polarizing plate having poor resistance, a compound added to obtain desired optical properties may be precipitated. Moreover, the polarization ability may be reduced by light, particularly ultraviolet rays. The polarizing plate may be caused by at least one factor such as a decrease in transmittance, generation of a bright spot, or a decrease in polarization ability, which may be reflected in a feeling of fatigue or discomfort in moving image observation.

  In order to improve the quality of the display device, it is possible to dispose another functional layer on the film A used for the polarizing plate of the present invention and the film B depending on the application.

  For example, the film may be affixed to the surface of a polarizing plate of the present invention, or a film containing a known functional layer as a display for anti-reflection, anti-glare, scratch resistance, dust adhesion prevention, and brightness improvement. It is not limited to.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

  First, measurement methods for various characteristics will be described.

(Measurement of cellulose ester film substitution degree and acetylation degree)
The degree of substitution of acetyl (DSa) and the degree of substitution of propionyl (DSp) were measured according to ASTM-D817-96. The degree of substitution of acetic acid (DSa) is the number of all OH groups in the cellulose ester molecule reacted with the number of acetic acid substituted, and it is expressed in glucopyranose units. It takes a value from 0 to 3.

  The degree of acetylation is mass% of acetic acid in cellulose acetate and is calculated according to the following formula.

Degree of acetylation = {DSa × (molecular weight of CH ₃ COOH)} / {molecular weight of (C ₆ H ₁₀ O ₅ ) + DSa × (molecular weight of CH ₂ CO) + DSp × (molecular weight of CH ₃ CHCO)}
(Ro, Rth)
The average refractive index of the film constituting material was measured using an Abbe refractometer (4T). Moreover, the thickness of the film was measured using calipers.

  Retardation of a film having a wavelength of 590 nm under the same environment using an automatic birefringence meter KOBRA-21ADH (manufactured by Oji Scientific Instruments) for 24 hours in an environment of 23 ° C. and 55% RH. Measurements were made. The average refractive index and film thickness described above were input, and values for in-plane retardation (Ro) and thickness direction retardation (Rth) were obtained. The direction of the slow axis was also measured at the same time.

(Viewing angle characteristics)
For the evaluation of viewing angle characteristics, the transmitted light amount during black display and white display was measured using EZ-contrast manufactured by ELDIM. For the evaluation of the viewing angle, contrast = (transmitted light amount during white display) / (transmitted light amount during black display) was calculated.

Example 1
<< Film A >>
<Film A-101>
(Preparation of dope solution D-101)
Cellulose acetate (average degree of acetylation 60.1%) 100 parts by weight Triphenyl phosphate 9.5 parts by weight Ethylphthalyl ethyl glycolate 2.2 parts by weight Methylene chloride 440 parts by weight Ethanol 40 parts by weight The solution was completely dissolved while being heated and stirred, and Azumi Filter Paper No. No. 24 was filtered to prepare a dope solution D-101. The dope solution D-101 was filtered with Finemet NF manufactured by Nippon Seisen Co., Ltd. in the film production line. (A part of the dope solution D-101 was also used to prepare the in-line additive solution IN-101 below.)
(Silicon dioxide dispersion B)
Aerosil 200V (manufactured by Nippon Aerosil Co., Ltd.) 2 parts by mass (average diameter of primary particles 12 nm, apparent specific gravity 100 g / liter)
18 parts by mass or more of ethanol was stirred and mixed with a dissolver for 30 minutes, and then dispersed with Manton Gorin. The liquid turbidity after dispersion was 100 ppm. 18 parts by mass of methylene chloride was added to the silicon dioxide dispersion B with stirring, and the mixture was stirred for 30 minutes with a dissolver to prepare a silicon dioxide dispersion dilution.

(Preparation of inline additive solution IN-101)
Methylene chloride 100 parts by weight Dope solution D-101 34 parts by weight Tinuvin 109 (manufactured by Ciba Specialty Chemicals) 5 parts by weight Tinuvin 171 (manufactured by Ciba Specialty Chemicals) 5 parts by weight Tinuvin 326 (Ciba Specialty Chemicals) 3 parts by mass or more were put into a closed container, heated, stirred and completely dissolved and filtered.

  To this, 20 parts by mass of the above-prepared silicon dioxide dispersion diluted solution was added with stirring, and the mixture was further stirred for 60 minutes, and then filtered with a polypropylene wind cartridge filter TCW-PPS-1N manufactured by Advantech Toyo Co., Ltd. IN-101 was prepared.

  In-line additive solution IN-101B was filtered with Finemet NF manufactured by Nippon Seisen Co., Ltd. in the in-line additive solution line. Add 2.5 parts by mass of filtered inline additive IN-101 to 100 parts by mass of filtered dope liquid D-101, and mix thoroughly with an inline mixer (Toray static type in-pipe mixer Hi-Mixer, SWJ). Then, using a belt casting apparatus, it was cast uniformly onto a stainless steel band support at a temperature of 35 ° C. and a width of 1800 mm. With the stainless steel band support, the solvent was evaporated until the amount of residual solvent reached 100%, and then peeled off from the stainless steel band support. The peeled cellulose ester web was evaporated at 35 ° C., slit to 1650 mm width, and then stretched 1.1 times in the TD direction (direction perpendicular to the film transport direction) with a tenter, Dried at the drying temperature. At this time, the residual solvent amount when starting stretching with a tenter was 20%. Then, drying was completed while transporting the drying zone at 120 ° C. and 110 ° C. with a number of rolls, slitting to a width of 1400 mm, giving a knurling of 15 mm in width and 10 μm in height at both ends of the film, and winding it on a core. Film A-101 was obtained. The residual solvent amount of the A-101 film immediately after the production in this step was 0.1%, the film thickness was 80 μm, and the winding number was 4000 m.

<Production of Film 102 to Film 108>
Film preparation was performed in the same manner as the film 101. The acetylation degree of cellulose acetate, the addition amounts of Tinuvin 109, 171 and 326, the deterioration inhibitor, the retardation improver and the film thickness of the sample were changed as shown in Table 1. As a UV absorber of sample 105, 2-hydroxy-4-benzyloxybenzophenone was added as shown in Table 1 instead of all of tinuvin 109, 171 and 326. Each film was dried so that the residual solvent amount was 0.1% or less.

The amount per 1 m ² of the UV absorber, the deterioration inhibitor and the retardation improver in the films 101 to 108 is separately extracted from the film-dried film and quantified by high performance liquid chromatography, gas chromatography and mass spectrum analysis. The mass% relative to the resin constituting the film (here, cellulose acetate) was determined. The ultraviolet absorber (total value) per 1 m ² , the deterioration inhibitor, and the retardation improver are calculated according to the film thickness and weight and the quantified composition, and the results are shown in Table 1. As a result of quantitative analysis of the plasticizer in the same manner, the plasticizers of Sample 101 to Sample 108 were in the range of 10.2% by mass to 10.8% by mass with respect to the film mass in all the samples.

<Table 1>
Sample No. Degree of acetylation Film thickness UV degradation Retardation
(%) (Μm) Absorber Inhibitor * Enhancer **
(G / m ² ) (g / m ² ) (g / m ² )
101 60.1 80 1.2 0 0
102 60.1 80 1.2 0 0.1
103 60.1 80 1.2 0.11 0
104 60.1 80 2.0 0 1.2
105 60.1 80 1.2 *** 0 0
106 60.1 80 0 0 0
107 60.1 80 3.6 0 0
108 58.0 57 1.2 0 0
*: Tribenzylamine **: Triazine derivative having the following structure **: 2-hydroxy-4-benzyloxybenzophenone

<< Film B >>
<Film B-201>
It was prepared in the same manner as the film sample A-101 until the belt was cast.

  Next, using a belt casting apparatus, the belt was uniformly cast on a stainless steel band support at a temperature of 35 ° C. and a width of 1800 mm. With the stainless steel band support, the solvent was evaporated until the amount of residual solvent reached 100%, and then peeled off from the stainless steel band support. The web of the peeled cellulose ester film was evaporated at 55 ° C., slit to 1650 mm width, and then stretched 1.3 times at 130 ° C. in the TD direction (direction perpendicular to the film transport direction) with a tenter. At this time, the residual solvent amount when starting stretching with a tenter was 18%. Then, drying was completed while transporting the drying zone at 120 ° C. and 110 ° C. with a number of rolls, slitting to a width of 1400 mm, giving a knurling of 15 mm in width and 10 μm in height at both ends of the film, and winding it on a core. Film B-201 was obtained. The residual solvent amount of the film B-201 was 0.1%, the film thickness was 80 μm, and the winding number was 4000 m. At this time, the film B-201 had Ro = 4 nm and Rth = 52 nm. The results are shown in Table 2.

<Production of Film 202 to Film 206>
(Preparation of dope solution D-202)
Cellulose ester (cellulose acetate propionate acetyl group substitution degree 1.9, propionyl group substitution degree 0.8) 100 parts by weight Triphenyl phosphate 8 parts by weight Ethylphthalyl ethyl glycolate 2 parts by weight Methylene chloride 300 parts by weight Ethanol 60 Part by mass or more is put into a sealed container, heated, stirred and completely dissolved, and Azumi Filter Paper No. No. 24 was filtered to prepare a dope solution D-202. In the film production line, the dope solution D-202 was filtered with Finemet NF manufactured by Nippon Seisen Co., Ltd.
(Silicon dioxide dispersion C)
Aerosil 972V (manufactured by Nippon Aerosil Co., Ltd.) 10 parts by mass (average primary particle diameter 16 nm, apparent specific gravity 90 g / liter)
Ethanol 75 parts by mass or more was stirred and mixed with a dissolver for 30 minutes, and then dispersed with Manton Gorin. The liquid turbidity after dispersion was 200 ppm. 75 parts by mass of methylene chloride was added to the silicon dioxide dispersion C with stirring, and the mixture was stirred and mixed with a dissolver for 30 minutes to prepare a silicon dioxide dispersion dilution.
(Preparation of inline additive solution IN-201)
Methylene chloride 100 parts by mass Tinuvin 109 (Ciba Specialty Chemicals Co., Ltd.) 4 parts by mass Tinuvin 171 (Ciba Specialty Chemicals Co., Ltd.) 4 parts by mass Tinuvin 326 (Ciba Specialty Chemicals Co., Ltd.) 2 parts by mass or more Put in a container, heat, stir, dissolve completely and filter.

  To this, 20 parts by mass of the above-mentioned silicon dioxide dispersion diluted solution was added with stirring, and further stirred for 30 minutes, and then cellulose ester (cellulose acetate propionate acetyl group substitution degree 1.90, propionyl group substitution degree 0.80). 5 parts by mass was added with stirring, and the mixture was further stirred for 60 minutes, and then filtered through a polypropylene wind cartridge filter TCW-PPS-1N manufactured by Advantech Toyo Co., Ltd. to prepare an in-line additive solution C.

  In-line additive solution C was filtered with Finemet NF manufactured by Nippon Seisen Co., Ltd. in the in-line additive solution line. Add 4 parts by mass of the filtered in-line additive liquid IN-202 to 100 parts by mass of the filtered dope liquid D-202, mix thoroughly with an in-line mixer (Toray static type in-pipe mixer Hi-Mixer, SWJ), and then Then, using a belt casting apparatus, it was cast uniformly on a stainless steel band support at a temperature of 35 ° C. and a width of 1800 mm. With the stainless steel band support, the solvent was evaporated until the amount of residual solvent reached 100%, and then peeled off from the stainless steel band support. The web of the peeled cellulose ester film was evaporated at 55 ° C., slit to 1650 mm width, and then stretched 1.33 times at 130 ° C. in the TD direction (direction perpendicular to the film transport direction) with a tenter. At this time, the residual solvent amount when starting stretching with a tenter was 18%. Thereafter, drying is completed while transporting the drying zone of 120 ° C. and 110 ° C. with a number of rolls, slitting to a width of 1400 mm, a knurling process having a width of 15 mm and an average height of 10 μm is applied to both ends of the film, and an initial winding tension of 220 N / M and a final tension of 110 N / m were wound around a 6-inch inner diameter core to obtain a cellulose ester film sample 202. The residual solvent amount of the cellulose ester film was 0.1%, the average film thickness was 80 μm, and the winding number was 4000 m. The cellulose ester film had Ro of 51 nm and Rth of 132 nm.

  Similarly to the film 202, the films 203 to 206 and 209 use cellulose acetate propionate (DSa / DSp) = (1.90 / 0.80) and the total acyl group substitution = 2.70, and the films 207, 209 Used cellulose acetate propionate (DSa / DSp) = (2.05 / 0.70) and total acyl group substitution = 2.75.

  In the films 202 to 209, the addition amounts of Tinuvin 109, 171 and 326, the deterioration inhibitor, the retardation improver, and the dry film thickness of the sample were adjusted as shown in Table 2. Moreover, the draw ratio at the time of extending | stretching to a TD direction with a tenter was suitably adjusted so that it might become retardation Ro and Rth of Table 2 in the range of 1.25 or more and 1.40 or less. Each film was adjusted so that the residual solvent amount was 0.1% or less immediately after the production of this step.

The amount per 1 m ² of UV absorber, deterioration inhibitor, and retardation improver in Film 201 to Film 209 is fractionated and extracted from the film-dried film, and quantified by high performance liquid chromatography, gas chromatography, and mass spectrum analysis. The mass% with respect to resin (here, cellulose ester) constituting the film was determined. The ultraviolet absorber, deterioration inhibitor, and retardation improver per 1 m ² are calculated from the film thickness and mass and the quantified composition, and the results are shown in Table 2.

  As a result of quantitative analysis of the plasticizer in the same manner, the plasticizers of Samples 201 to 209 were in the range of 10.2% by mass to 10.8% by mass with respect to the film mass in all the samples.

<Table 2>
Sample film thickness UV degradation Retardation Ro Rth
No. (Μm) Absorber Inhibitor * Enhancer **
(G / m ² ) (g / m ² ) (g / m ² ) (nm) (nm)
201 80 1.20 0 4 52
202 80 1.20 0 51 110
203 80 0 0 0 51 110
204 80 0 0.11 0.6 58 158
205 80 1.20 2.0 76 228
206 110 0 0 3.2 75 313
207 88 0 0 0 48 125
208 85 0 0.11 0.6 39 166
209 80 0.8 0 0 40 119
*: Tribenzylamine **: Triazine derivative with the above structure <Preparation of polarizing plate>
Using the cellulose ester film original fabric sample prepared in Example 1, the alkali saponification treatment and the polarizing plate described below were performed.

<Alkali saponification treatment>
Saponification step 2M-NaOH 50 ° C. 90 seconds Water washing step Water 30 ° C. 45 seconds Neutralization step 10% HCl 30 ° C. 45 seconds Water washing step Water 30 ° C. 45 seconds After saponification treatment, water washing, neutralization, water washing are performed in this order. Subsequently, it dried at 80 degreeC.

<Production of polarizer>
A 120 μm-thick long roll polyvinyl alcohol film was immersed in 100 parts by mass of an aqueous solution containing 1 part by mass of iodine and 4 parts by mass of boric acid, and stretched 6 times at 50 ° C. in the conveying direction to form a polarizing film.

  The alkali saponification-treated sample films of Samples 101 to 108 are bonded to one side of the polarizing film as a pressure-sensitive adhesive with a completely saponified polyvinyl alcohol 5% aqueous solution, respectively, and the samples 201 to 209 on the reverse side of the polarizing film. The alkali-treated sample films were bonded in the same manner as shown in Table 3 to prepare polarizing plate samples 301 to 314. The polarizing plate sample 315 was prepared in the same manner as the polarizing plate sample having the configuration shown in Table 3 using the sample 209 shown in Table 2 as the film A.

<Table 3>
Polarizing plate Film Film Display quality Degradation test 1 Degradation test 2 Movie evaluation Remarks A B UV irradiation resistance 1 / resistance 2
301 101 201 × ◎ ◎ / ◎ × Comparative Example 302 106 203 ◎ × ◎ / ◎ × Comparative Example 303 101 203 ◎ ◎ ◎ / ◎ ◎ Present Invention 304 101 202 ◎ ◎ ◎ / ○ ○ Present Invention 305 101 204 ◎ ◎ ○ / ◎ ◎ Present invention 306 102 204 ◎ ○ ○ / ◎ ○ Present invention 307 103 205 ○ ○ ○ / ○ ○ Present invention 308 104 205 ○ ◎ ○ / ○ ○ Present invention 309 105 203 ◎ ○ ◎ / ◎ ◎ Present invention 310 107 201 × ◎ × / ◎ × Comparative Example 311 106 206 × × × / × × Comparative Example 312 108 203 ◎ ◎ ○ / ○ ○ Present invention 313 101 207 ◎ ◎ ◎ / ◎ ◎ Present invention 314 101 208 ◎ ◎ ○ / ◎ ○ Invention 315 209 204 ◎ ○ ◎ / ○ ○ Invention << Evaluation of display quality: Measurement of viewing angle of VA liquid crystal display >>
A Fujitsu 15-inch liquid crystal display VL-1530S was installed so as to be parallel to the horizontal plane. The polarizing plate previously bonded to the display was peeled off and bonded so that the transmission axis of the polarizing plate produced in the configuration of Table 3 was in the same direction as the transmission axis of the polarizing plate previously bonded. Two polarizing plates were prepared in the same manner, and one piece was used for each of the observation surface and the backlight for the liquid crystal cell as shown in FIG. In each polarizing plate, the protective film B side was bonded so that it might be arrange | positioned at the liquid crystal cell side.

  For viewing angle evaluation, the viewing angle of the liquid crystal panel on which the viewing angle compensation elliptically polarizing plate of the present invention obtained above was bonded was measured using EZ-contrast manufactured by ELDIM.

  The measuring method evaluated the range of the inclination angle from the normal direction with respect to the panel surface in which the contrast ratio at the time of white display and black display of a liquid crystal panel is 10 or more. When the normal is 0 °, the viewing angle region becomes wider as the tilt angle increases.

  The evaluation panel was evaluated based on the contrast value in an oblique 45 ° azimuth when the horizontal direction was 0 °.

A: The inclination angle from the normal direction to the panel surface is 80 ° or more. ○: The inclination angle from the normal direction to the panel surface is 70 ° or more and less than 80 °. X: The inclination from the normal direction to the panel surface. The angle is less than 70 °.

《Deterioration test》
The configuration of the liquid crystal display device is shown in the following table.

Degradation test 1 <ultraviolet irradiation treatment>
The same polarizing plate as the polarizing plate used in Table 3 is bonded to a glass plate using an acrylic adhesive, and from the film A side, illuminance is 70,000 lux with a xenon long life weather meter, forced degradation at 40 ° C for 500 hours Went.

  The light-irradiated polarizing plate was peeled off from the glass plate and cut into two. The polarization behavior was visually observed at room temperature with these in a crossed Nicols state. It can be visually confirmed that the darkened state has polarizing ability.

  Evaluation was performed by comparison with observation under the same crossed Nicols of the sample not irradiated with ultraviolet rays, and Table 3 shows these results.

(Change in polarization before and after degradation test)
◎: No change ○: Slightly deteriorated but sufficiently polarizable ×: Polarized property almost disappeared Deterioration test 2 <High temperature-high humidity resistance test>
A polarizing plate having the same configuration as the polarizing plate used in Table 3 was treated in a thermostatic chamber capable of maintaining a moist heat environment under the following environment. The processing conditions are 60 ° C., 90% RH, and 500 hours.

  The treated polarizing plate was allowed to stand at 23 ° C. and 55% RH at room temperature for 24 hours, and then observed with a polarizing plate / backlight configuration. It installed so that the film B side of a polarizing plate might turn into a backlight side, and observation evaluation was performed from the front of a polarizing plate.

(Tolerance 1)
A: Good before change and good: B: Slightly deteriorated white, but at a practically no problem level: White turbidity was observed. The processed polarizing plate after the same treatment was cut into two sheets. After standing at 23 ° C. and 55% RH at room temperature for 24 hours, the polarization behavior was visually observed from the front with the two films in a crossed Nicol state so that the film A side was inside.

  Subsequently, the polarizing behavior was visually observed from the front in the configuration of observer / polarizer orthogonal Nicol / backlight, with the two films B being in the state of orthogonal Nicols so that the films B were inward.

(Tolerance 2)
◎: Not changed ○: Slightly deteriorated but sufficiently black ×: Bright spots are observed and cannot be used as a polarizing plate for display << Movie observation evaluation >>
In the polarizing plates 301 to 315, the polarizing plate was fixed to a glass plate with a clip. The surface of the film A was subjected to the ultraviolet irradiation treatment performed in the deterioration test 1 in the same manner. However, the irradiation time was 100 hours.

  These polarizing plates were subjected to the same treatment as the wet heat resistance test conducted in the degradation test 2, and then allowed to stand at 23 ° C. and 55% RH for 24 hours.

  The processed polarizing plate was placed on and bonded to a 15-inch liquid crystal display VL150SD manufactured by Fujitsu in the same manner as the evaluation of display quality. A moving image recording a moving image of a TV program was displayed on the same display via a personal computer, and a comparative experiment was performed. A moving image was observed for 2 minutes at a position 3 m away from the front of the display, and sensory evaluation was performed.

A: No fatigue or discomfort immediately during observation or immediately after observation B: Slightly tired but no discomfort after observation C: Discomfort of images is remarkable, and eyes are tired during observation. Durability is remarkably improved with respect to the environment for irradiation and wet heat storage. The liquid crystal display device provided with this polarizing plate is excellent in that the display quality is improved and the durability is compatible.

  In the above evaluation, the polarizing plate having the same observation side and backlight side has a symmetrical contrast region, but the observation side polarizing plate is the polarizing plate sample 306 and the backlight side polarizing plate sample 305 is the same apparatus. As a result, it was a left-right asymmetric contrast region. In this case, although durability and display quality were compatible with each other sufficiently compared with the comparative polarizing plate, there was a slight sense of incongruity. Therefore, when bonding to both sides of the liquid crystal display device on the observation side and the backlight side as described above, the constituent parts of the polarizing plate (film A / polarizer / film B) of the present invention are the same. It turns out that it is preferable.

Example 2
<< Viewing angle measurement of TN type liquid crystal display device >>
The polarizing plate of the present invention obtained above is peeled off the optical film and polarizing plate of NEC 15-type liquid crystal display Multi Sync LCD1525J previously bonded, and the absorption axis of the polarizing plate of the present invention is previously bonded. Bonding was performed in the same direction as the absorption axis of the polarizing plate.

  For viewing angle evaluation, the viewing angle of the liquid crystal panel on which the viewing angle compensation elliptically polarizing plate of the present invention obtained above was bonded was measured using EZ-contrast manufactured by ELDIM.

  The viewing angle was evaluated in the same manner as in Example 1. As a measure of the viewing angle, when the horizontal direction of the display is set to 0 °, the contrast of the 0 ° azimuth is evaluated in the same manner, and the liquid crystal display device bonded with the polarizing plate of the present invention has both durability and display quality. It was clear that

It is a figure explaining the extending | stretching angle in an extending | stretching process. It is the schematic which shows an example of the tenter process used for this invention. It is a schematic diagram which shows the structure of the display apparatus of this invention.

Explanation of symbols

1a Film A1
1b Film A2
2a Film B1
2b Film B2
5a, 5b Polarizer 3a, 3b Film slow axis direction 4a, 4b Polarizer transmission axis direction 6a, 6b Polarizer 7 Liquid crystal cell 9 Liquid crystal display device

Claims (17)

In a polarizing plate used for a display device that displays and observes an image of a display device through at least one polarizing plate, the polarizing plate is composed of a polarizer and at least two films A and B, and the film A is a polarizer. A polarizing plate characterized in that it is present on the side farther from the display device, and the film B is present on the side closer to the display device than the polarizer, and satisfies all of the following relationships (1) to (4).
(1) Formula I Wa> Wb ≧ 0
Formula II 0.1 (g / m ² ) <Wa <3.0 (g / m ² )
(Wherein, Wa is the amount of the ultraviolet absorber and / or antidegradants per 1 m ² in the film ^{A (g / m 2),} Wb is the ultraviolet absorbent per 1 m ² in the film B and / or antidegradants Represents the amount (g / m ² ).)
(2) Formula III 0 ≦ Ra ≦ Rb
Formula IV 0 (g / m ² ) ≦ Rb ≦ 3.0 (g / m ² )
(In the formula, Ra represents the amount of retardation improver per 1 m ² of film A (g / m ² ), and Rb represents the amount of retardation improver per 1 m ² of film B (g / m ² ).)
(3) Ro of film B defined by the following formula (V) is in the range of 20 nm to 95 nm, and Rth of film B defined by the following formula (VI) is in the range of 70 nm to 400 nm. Here, Ro and Rth are retardation values of 590 nm, and are measured values in an environment of 23 ° C. and 55% RH.
Formula V Ro = (nx−ny) × d
Formula VI Rth = {(nx + ny) / 2−nz} × d
(Where nx is the refractive index in the slow axis direction in the film plane, ny is the refractive index in the fast axis direction in the film plane, nz is the refractive index in the thickness direction of the film, and d is Represents film thickness.)
(4) Film A is a cellulose acetate film or a cellulose acetate propionate film, and film B is a cellulose acetate propionate film. The polarizing plate according to claim 1, wherein the film A and the film B satisfy a relationship between the following formulas VII and VIII.
Formula VII 0.1 (g / m ² ) <(Wa + Ra) <3.0 (g / m ² )
Formula VIII 0 (g / m ² ) ≦ (Wb + Rb) <3.0 (g / m ² ) The polarizing plate according to claim 1 or 2, wherein at least one of the film A and the film B contains a plasticizer in an amount of 1% by mass to less than 11% by mass with respect to the film mass. The film A is a cellulose acetate film, and the film B is a cellulose ester having a total acyl group substitution degree of 2.5 to 2.9 and an acetyl group substitution degree of 1.4 to 2.3. It is a cellulose-ester film which is a range, The polarizing plate of any one of Claims 1-3 characterized by the above-mentioned. The polarizing plate according to claim 1, wherein the cellulose acetate film contains an ultraviolet absorber, and the ultraviolet absorber is a benzophenone derivative or a benzotriazole derivative. The polarizing plate according to claim 1, wherein the retardation improver is a compound having a 1,3,5-triazine ring. 7. The film according to claim 1, wherein at least one of the film A and the film B is produced by a solution casting method, and the retardation is controlled by stretching in the presence of a residual solvent. 2. The polarizing plate according to item 1. The polarizing plate according to claim 1, wherein the film A and the film B are bonded to a polarizer by a saponification treatment. The retardation value of the said film A and the film B differs, The polarizing plate of any one of Claims 1-8 characterized by the above-mentioned. The polarizing plate according to claim 1, wherein the film B satisfies 30 nm <Ro ≦ 70 nm. The polarizing plate according to claim 1, wherein the film B satisfies 90 nm <Rth ≦ 200 nm. It is a polarizing plate of any one of Claims 1-11, Comprising: The transmission axis of a polarizer is substantially parallel with respect to a roll elongate direction, and the slow axis of the film B is a roll width direction. A roll-shaped polarizing plate characterized by being substantially parallel to. A display device using the polarizing plate according to any one of claims 1 to 11 or the roll-shaped polarizing plate according to claim 12 is a liquid crystal display device. The display device according to claim 13, wherein the liquid crystal display device is a multi-domain liquid crystal display device. The display device according to claim 13, wherein the liquid crystal display device is in a vertical alignment mode. The display device according to any one of claims 13 to 15, wherein two polarizing plates are respectively polarizing plate 1 (film A1 / polarizer / film B1) and polarizing plate 2 (film B2 / polarizer / film A2). The configuration viewed from the cross-sectional side of the display device is the order of polarizing plate 1 (film A1 / polarizer / film B1) / liquid crystal cell / polarizing plate 2 (film B2 / polarizer / film A2), and The arrangement when observed from the vertical direction of the surface of the display device is that the transmission axes of the two polarizing plates are substantially perpendicular, the film B1 and the film B2 are substantially the same film, the film B1 and the film A display device, wherein a slow axis of B2 is substantially parallel to a transmission axis of an adjacent polarizer. The display device according to claim 13, wherein the display device displays a moving image and a color.

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