JP6410687B2 - Optical film, optical film manufacturing method, polarizing plate, and liquid crystal display device - Google Patents

Description

  The present invention relates to an optical film having improved durability when used in a polarizing plate. The present invention further relates to a method for producing the optical film, a polarizing plate having the optical film, and a liquid crystal display device.

  Display prices are falling due to the spread of displays to emerging countries. Therefore, simplification of packaging at the time of transportation and storage of the panel has been promoted, and there is a demand for little change in quality even during transportation under high temperature and low humidity or high temperature and high humidity. In addition, there is a demand for a thinner film due to a thinner display. Examples of quality deterioration of the polarizing plate under high temperature and low humidity include changes in the color of the polarizing plate due to changes in the orthogonal transmittance of the polarizer on the long wave side, and changes in optical characteristics.

  Patent Document 1 includes a highly hygroscopic compound having a moisture content difference in an amorphous state (a difference between a moisture content at 25 ° C. and a relative humidity of 10% and a moisture content at 25 ° C. and a relative humidity of 80%) of 2% or more. A cellulose acylate film is described, and a nitrogen-containing compound is described as the highly hygroscopic compound. Patent Document 2 describes a cellulose acylate film containing cellulose acylate, a polycondensed ester containing an aliphatic dicarboxylic acid residue and an aliphatic diol residue, and a nitrogen-containing aromatic compound. However, Patent Documents 1 and 2 do not mention adjusting the calcium content in the cellulose acylate film.

  In Patent Document 3, in the cellulose ester in which the ratio of mannose in all the constituent sugars is 0.1 mol% or more and 1.4 mol% or less, the amount of hexane extract is 0.1 ppm or more and 30 ppm or less, and the amount of calcium with respect to the cellulose ester As cellulose esters having a concentration of 50 ppm or more and 150 ppm or less. However, Patent Document 3 does not describe cellulose acylate having an average acyl substitution degree of 2.0 to 2.6, and does not describe improvement of the color of the polarizing plate.

JP 2012-215817 A JP 2013-76872 A JP 2010-202793 A

  As described above, the deterioration of the quality of the polarizing plate includes a change in the color of the polarizing plate due to a change in the orthogonal transmittance of the polarizer on the long wave side, and a change in the optical characteristics, and a means for improving these quality deteriorations is desired. It was. This invention makes it the problem which should be solved to provide the optical film which can suppress the color change and optical characteristic change of a polarizing plate under high temperature, low humidity, and high temperature, high humidity. Furthermore, this invention makes it the subject which should be solved to provide the manufacturing method of the said optical film, the polarizing plate which has the said optical film, and a liquid crystal display device.

As a result of intensive studies to solve the above-mentioned problems, the present inventor used cellulose acylate having an average acyl substitution degree of 2.0 to 2.6, and the calcium content in the whole film was 5 × 10 ⁻⁵ g / g or more. By making the compound less than 5 × 10 ⁻⁴ g / g and adding the compound represented by the general formula 1 described later, it is possible to suppress the change in optical properties of the polarizing plate, and due to the change in the orthogonal transmittance on the long wavelength side of the polarizing plate. It was found that color change can be suppressed. The present invention has been completed based on these findings.

That is, according to the present invention, the following inventions are provided.
(1) It contains cellulose acylate having an average acyl substitution degree of 2.0 to 2.6, and the calcium content in the whole film is 5 × 10 ⁻⁵ g / g or more and less than 5 × 10 ⁻⁴ g / g, An optical film comprising a compound represented by the following general formula 1:
In General Formula 1, X and Y each independently represent —N— or —CH—;
Q ₁ , Q ₂ and Q ₃ each independently represents a single bond or a divalent linking group;
R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a halogen group or a heterocyclic group.
(2) A cellulose acylate film having an average acyl substitution degree of 2.6 to 3.0 is laminated on at least one surface of the cellulose acylate film having an average acyl substitution degree of 2.0 to 2.55. The optical film as described in (1).
(3) The optical film as described in (1) or (2) which contains 5 mass% or more and 15 mass% or less of the compound shown by General formula 1.
(4) The optical film according to any one of (1) to (3), comprising 1 to 9% by mass of a polycondensation ester of a dicarboxylic acid and an aliphatic diol.
(5) The optical film as described in (4) whose 50 mol% or more is a terephthalic acid component among the dicarboxylic acid components in the said polycondensation ester.
(6) The optical film according to any one of (1) to (5), wherein the film thickness is 5 μm or more and 50 μm or less.
(7) From the one surface of the film to the calcium content in the region having a depth of 2 μm and the calcium content in the other surface of the film to the region having a depth of 2 μm, the depth of 2 μm or more from the one surface of the film to the above of the film The optical film according to (6), wherein the calcium content in the region from the other surface to a depth of 2 μm is higher.
(8) The optical film according to any one of (1) to (7), wherein α defined by the following formula 2 is 0 or more and 0.20 or less:
Formula 2: α = [Rth (550) after time-initial Rth (550)] / initial Rth (550)
Here, the initial Rth (550) is Rth measured at a wavelength of 550 nm after conditioning for 24 hours in a 25 ° C. and 60% relative humidity environment, and the Rth (550) after aging. Rth measured at a wavelength of 550 nm after measurement of the initial Rth (550) value, storage for 1000 hours in a dry environment at 80 ° C., and then conditioning for 24 hours in an environment of 25 ° C. and a relative humidity of 60%. It is. Rth indicates retardation in the thickness direction.
(9) The optical according to any one of (1) to (8), comprising a film-forming step of casting a dope containing cellulose acylate, calcium and a compound represented by the following general formula 1 on a support. A method for producing a film.
In General Formula 1, X and Y each independently represent —N— or —CH—;
Q ₁ , Q ₂ and Q ₃ each independently represents a single bond or a divalent linking group;
R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a halogen group or a heterocyclic group.
(10) A core layer forming dope containing the cellulose acylate, calcium and the compound represented by the general formula 1 described in (1), and a skin layer forming dope containing cellulose acylate, The method for producing an optical film according to (9), which is a step of co-casting on a support.
(11) The method for producing an optical film according to (10), wherein the calcium content with respect to the cellulose acylate mass in the core layer forming dope is larger than the calcium content with respect to the cellulose acylate mass in the skin layer forming dope.
(12) A polarizing plate having a polarizer and the optical film according to any one of (1) to (9).
(13) A liquid crystal display device having the polarizing plate according to (12).
(14) Δu′v ′ represented by the following formula 3 which is a color change at the time of black display after humidity conditioning for 72 hours in an environment of 25 ° C. and a relative humidity of 60% is 0 or more and 0.05 or less, (13 ) Liquid crystal display device described in:
Formula 3:
In the formula, u′max and v′max are the maximum hues u ′ and v ′ among the values measured in the range of azimuth angle 0 to 360 ° at a polar angle of 60 °, and u′min and v ′. min is the minimum tint u ′ and v ′ among the values measured in the range of azimuth angle 0 to 360 ° when the polar angle is 60 °.

  According to the optical film, the manufacturing method and the polarizing plate of the present invention, it is possible to suppress changes in color and optical properties of the polarizing plate under high temperature and low humidity and high temperature and high humidity. According to the liquid crystal display device of the present invention, the color change when viewed from an oblique direction and the color change after storage at high temperature and low humidity are good.

FIG. 1 is a schematic view in the vicinity of a casting die. FIG. 2 is an explanatory diagram of an example of co-casting.

  Hereinafter, the present invention will be described in detail. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

In the present specification, Re (λ) and Rth (λ) represent in-plane retardation (nm) and retardation in the thickness direction (nm) at wavelength λ, respectively. Note that the wavelength λ is 550 nm unless otherwise specified in this specification. Re (λ) is measured by making light having a wavelength of λ nm incident in the normal direction of the film in KOBRA 21ADH or WR or KOBRA CCD series (manufactured by Oji Scientific Instruments).
When the film to be measured is represented by a uniaxial or biaxial refractive index ellipsoid, Rth (λ) is calculated by the following method.
Rth (λ) is the above-mentioned Re (λ), with the in-plane slow axis (determined by KOBRA 21ADH or WR or KOBRA CCD series) as the tilt axis (rotary axis) (if there is no slow axis, film A total of 6 points of light of wavelength λ nm are incident from the inclined direction in 10 degree steps from the normal direction to 50 degrees on one side with respect to the film normal direction (with any direction in the plane as the rotation axis). KOBRA 21ADH or WR or KOBRA CCD series is calculated based on the measured retardation value, the assumed value of the average refractive index, and the input film thickness value.
In the above, in the case of a film having a direction in which the retardation value is zero at a certain tilt angle with the in-plane slow axis from the normal direction as the rotation axis, the retardation value at a tilt angle larger than the tilt angle is After changing the sign to negative, KOBRA 21ADH or WR or KOBRA CCD series calculates. In selecting the measurement wavelength λnm, the wavelength selection filter can be exchanged manually, or the measurement value can be converted by a program or the like.
Note that the retardation value is measured from two inclined directions with the slow axis as the tilt axis (rotary axis) (in the case where there is no slow axis, the arbitrary direction in the film plane is the rotary axis), Rth can also be calculated from the following formula (X) and formula (XI) based on the value, the assumed value of the average refractive index, and the input film thickness value.

The above Re (θ) represents a retardation value in a direction inclined by an angle θ from the normal direction. In the formula, nx represents the refractive index in the slow axis direction in the plane, ny represents the refractive index in the direction orthogonal to nx in the plane, and nz represents the refractive index in the direction orthogonal to nx and ny. . d represents a film thickness.

In the case where the film to be measured cannot be expressed by a uniaxial or biaxial refractive index ellipsoid, that is, a film having no so-called optical axis, Rth (λ) is calculated by the following method.
Rth (λ) is −50 degrees with respect to the normal direction of the film, with Re (λ) being the in-plane slow axis (determined by KOBRA 21ADH or WR or KOBRA CCD series) as the tilt axis (rotation axis). From 10 degrees to +50 degrees with light of wavelength λ nm incident from each inclined direction and measured 11 points, and based on the measured retardation value, the assumed average refractive index and the input film thickness value KOBRA 21ADH or WR is calculated.
In the above measurement, the assumed value of the average refractive index may be a value in a polymer handbook (John Wiley & Sons, Inc.) or a catalog of various optical films. Those whose average refractive index is not known can be measured with an Abbe refractometer. Examples of the average refractive index values of main optical films are given below:
Cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59).
By inputting these assumed values of average refractive index and film thickness, the KOBRA 21ADH or WR or KOBRA CCD series calculates nx, ny, and nz. Nz = (nx−nz) / (nx−ny) is further calculated from the calculated nx, ny, and nz.
The retardation can also be measured using AxoScan (AXOMETRICS).

In the present invention, the “slow axis” of the retardation film or the like means a direction in which the refractive index is maximized. Further, the measurement wavelength of the refractive index is a value at λ = 550 nm in the visible light region unless otherwise specified.
Further, in the present specification, the numerical values and numerical ranges indicating the optical characteristics of the respective members indicate numerical values, numerical ranges and properties including generally allowable errors for the liquid crystal display device and the members used therefor. Shall be interpreted.

  In this specification, a number average molecular weight is defined as a polystyrene conversion value by gel permeation chromatography (GPC) measurement. In this specification, the number average molecular weight (Mn) is, for example, HLC-8220 (manufactured by Tosoh Corporation), and TSKgel (registered trademark) Super AWM-H (manufactured by Tosoh Corporation, 6.0 mm ID ×) as a column. Unless otherwise stated, the eluent is measured using a 10 mmol / L lithium bromide NMP (N-methylpyrrolidinone) solution.

[Optical film]
The optical film of the present invention contains cellulose acylate having an average acyl substitution degree of 2.0 to 2.6, and the calcium content in the whole film is 5 × 10 ⁻⁵ g / g or more and 5 × 10 ⁻⁴ g / g. And an optical film containing a compound represented by the following general formula 1.

  In the present invention, the optical property change of the polarizing plate can be suppressed by adding the compound represented by the general formula 1, and further, the green content is shifted to green by adjusting the calcium content in the entire film within the above range. It is possible to suppress the color change of the polarizing plate due to the change of the orthogonal transmittance on the long wavelength side of the polarizing plate. The mechanism by which the compound represented by the general formula 1 improves the change in the optical properties of the polarizing plate is that the nitrogen-containing compound represented by the general formula 1 is coordinated to the carbonyl group, so that the optical properties of cellulose acylate at high temperature and low humidity. We expect to cancel the change.

The calcium content in the whole film is 5 × 10 ⁻⁵ g / g or more and less than 5 × 10 ⁻⁴ g / g, preferably 5 × 10 ⁻⁵ g / g or more and 1.5 × 10 ⁻⁴ g / g or less. More preferably, it is 7 × 10 ⁻⁵ g / g or more and 1.5 × 10 ⁻⁴ g / g or less. By using cellulose acylate with an average acyl substitution degree of 2.0 to 2.6 and a calcium content in the above range, the color change when viewed obliquely and the color change after storage at high temperature and low humidity are good. It is.
Further, from the one surface of the film to the calcium content in the region having a depth of 2 μm and the calcium content in the other surface of the film to the region having a depth of 2 μm, the depth of 2 μm or more from the one surface of the film to the other of the film It is preferable that the calcium content in the region from the surface to a depth of 2 μm is higher. By suppressing the calcium content in the region from the surface to a depth of 2 μm, the band stripping property can be improved.

The calcium content was determined as follows.
0.06 g of a sample was weighed, 8 ml of 70% nitric acid (electronic industrial grade, manufactured by Kanto Chemical Co., Inc.) was added, sealed in a pressure-resistant container, heated in a microwave at 210 ° C. for 70 minutes, and incinerated. Remove the sample and measure the solution up to 80 g with pure water by high frequency inductively coupled plasma optical emission spectrometry (ICP-OES) method (PerkinElmer Optima7300DV, organic solvent mode (oxygen 40 ml / min, axial photometry)) It was determined by analyzing with a calibration curve method. The calcium content of the film surface layer is obtained by scraping up to 2 μm thickness from each surface of both sides of the optical film with a cutter blade, and using the collected powder, the calcium content contained in the powder is obtained by the above ICP-OES method. be able to. The calcium content in the center of the film can be determined by the above ICP-OES method using the sample obtained by removing the thickness of 2 μm from each surface of the optical film. .

(Layer structure of film)
The optical film of the present invention may be a single cellulose acylate film having an average acyl substitution degree of 2.0 to 2.6, or is composed of two or more cellulose acylate films having the same or different average acyl substitution degree. May be.

Preferably, in the optical film of the present invention, cellulose having an average acyl substitution degree of 2.6 to 3.0 is formed on at least one surface of a cellulose acylate film having an average acyl substitution degree of 2.0 to 2.55. An acylate film is laminated.
More preferably, the optical film of the present invention is present on a core layer containing cellulose acylate having an average acyl substitution degree of 2.00 to 2.55 and on one surface of the core layer, and has an average acyl substitution degree of 2.60. A first skin layer comprising cellulose acylate of ˜3.00 and a second skin layer comprising cellulose acylate having an average acyl substitution degree of 2.60 to 3.00 present on the other surface of the core layer And have.
In this specification, the “core layer” refers to a layer having the largest film thickness, and the “skin layer” refers to a layer that is thinner than the core layer and is in contact with the core layer. .

The optical film of the present invention can be produced by multilayerly casting a dope containing cellulose acylate on a support simultaneously or sequentially as described later, but even in this case, the layers are mixed with each other. In other words, a clear interface may not be formed.
Moreover, although the cellulose acylate in each layer may use only 1 type, or several cellulose acylates may be mixed in one layer, it is preferable that the cellulose acylate in each layer is 1 type.

(Film thickness)
The film thickness of the entire optical film of the present invention is preferably 5 μm or more and 50 μm or less, more preferably 5 μm or more and 45 μm or less, further preferably 7 μm or more and 40 μm or less, and more preferably 15 μm or more and 35 μm or less. Most preferred.
By setting the film thickness to 5 μm or more, it is preferable because the strength as a film can be secured, and by setting the film thickness to 50 μm or less, it is easy to cope with changes in humidity and maintain optical characteristics.

When the optical film of the present invention is composed of a core layer and a skin layer, the thickness of the skin layer is preferably 0.3 μm or more and 3 μm or less. It is more preferably 0.4 μm or more and 2.5 μm or less, and further preferably 0.5 μm or more and 2.0 μm or less. When two skin layers are present, the thickness of each skin layer is preferably within the above range.
The total film thickness can be measured with an electronic micrometer K402B manufactured by Anritsu Corporation.
The film thickness of the skin layer was measured by observing the film from the cross-sectional direction with an optical microscope or an electron microscope. When observing, flattening by a microtome may be performed as appropriate.

(Retardation Re and Rth)
The retardations Re and Rth of the optical film of the present invention are appropriately selected depending on the design of the liquid crystal cell and the optical film.
In general, it is preferable that 30 nm ≦ Re (550) ≦ 80 nm and 80 nm ≦ Rth (550) ≦ 150 nm are satisfied.
More preferably, 35 nm ≦ Re (550) ≦ 70 nm and 90 nm ≦ Rth (550) ≦ 140 nm are satisfied.
More preferably, 40 nm ≦ Re (550) ≦ 65 nm and 100 nm ≦ Rth (550) ≦ 130 nm are satisfied.
Re (550) represents the in-plane retardation of the film at a wavelength of 550 nm, and Rth (550) represents the thickness direction retardation of the film at a wavelength of 550 nm.

In the optical film of the present invention, α defined by the following formula 2 is preferably 0 or more and 0.20 or less.
Formula 2: α = [Rth after time (550) −initial Rth (550)] / initial Rth (550)
Here, the initial Rth (550) is Rth measured at a wavelength of 550 nm after humidity adjustment for 24 hours in a 25 ° C. and 60% relative humidity environment, and the Rth after the time (550). Rth measured at a wavelength of 550 nm after measurement of the initial Rth (550) value, storage for 1000 hours in a dry environment at 80 ° C., and then conditioning for 24 hours in an environment of 25 ° C. and a relative humidity of 60%. (550). Rth (550) indicates retardation in the thickness direction of the film at a wavelength of 550 nm.
Here, the 80 ° C. dry environment indicates an environment in a thermostat kept at 80 ° C. The incubator used in this experiment is not particularly limited as long as it is a commercially available incubator. For example, a constant temperature incubator DN64 manufactured by Yamato Scientific Co., Ltd. can be preferably used.

<Cellulose acylate>
The cellulose acylate used in the present invention is not particularly limited. Examples of cellulose acylate raw materials include cotton linter and wood pulp (hardwood pulp, conifer pulp). Cellulose acylate obtained from any raw material can be used. In some cases, cellulose acylate obtained from multiple types of raw materials is used. You may mix and use. For example, in Marusawa and Uda, “Plastic Materials Course (17) Fibrous Resin”, published by Nikkan Kogyo Shimbun (published in 1970) and the Japan Institute of Invention and Technology Publication No. 2001-1745 (pages 7-8) The cellulose described can be used.

  Glucose units having β-1,4 bonds constituting cellulose have free hydroxyl groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer obtained by acylating part or all of these hydroxyl groups with an acyl group. The average degree of acyl substitution means the ratio of acylation of the hydroxyl groups of cellulose located at the 2nd, 3rd and 6th positions (100% acylation has a degree of substitution of 1).

  The measuring method of acetyl substitution degree can be implemented according to ASTM D-817-91.

  When the optical film of the present invention is composed of a monolayer cellulose acylate film, the average acyl substitution degree of the whole film is preferably 2.0 to 2.6, and the average acyl substitution degree of the whole film is It is preferably 2.2 to 2.55, and more preferably 2.3 to 2.5. The average acyl substitution degree of the whole film can be obtained by calculation from the acyl substitution degree of each cellulose acylate used and the amount of each cellulose acylate used.

  When the optical film of the present invention is composed of a core layer and a skin layer, the average acyl substitution degree of the cellulose acylate of the core layer is preferably 2.00 to 2.55, and 2.2 to 2.55. More preferably, it is 2.3 to 2.5. The average acyl substitution degree of the cellulose acylate of the skin layer is preferably 2.60 to 3.00, more preferably 2.70 to 2.90, and further preferably 2.80 to 2.90. preferable.

  The acyl group having 2 or more carbon atoms of cellulose acylate in the present invention may be an aliphatic group or an allyl group, and is not particularly limited. These are, for example, cellulose alkylcarbonyl esters, alkenylcarbonyl esters, aromatic carbonyl esters, aromatic alkylcarbonyl esters, and the like, each of which may further have a substituted group. Preferred examples of these are acetyl group, propionyl group, butanoyl group, heptanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, isobutanoyl group. Group, tert-butanoyl group, cyclohexanecarbonyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group and the like. Among these, an acetyl group, a propionyl group, a butanoyl group, a dodecanoyl group, an octadecanoyl group, a tert-butanoyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, a cinnamoyl group, and the like are more preferable, and an acetyl group is particularly preferable. A propionyl group and a butanoyl group (when the acyl group has 2 to 4 carbon atoms), more preferably an acetyl group (when the cellulose acylate is cellulose acetate).

In the acylation of cellulose, when an acid anhydride or acid chloride is used as an acylating agent, an organic acid such as acetic acid or methylene chloride is used as an organic solvent as a reaction solvent.
As the catalyst, when the acylating agent is an acid anhydride, a protic catalyst such as sulfuric acid is preferably used, and when the acylating agent is an acid chloride (for example, CH ₃ CH ₂ COCl), Basic compounds are used.

The most common industrial synthesis method of cellulose mixed fatty acid ester is to use cellulose corresponding to fatty acid corresponding to acetyl group and other acyl groups (acetic acid, propionic acid, valeric acid, etc.) or their anhydrides. This is a method of acylating with a mixed organic acid component.
The cellulose acylate used in the present invention can be synthesized, for example, by the method described in JP-A-10-45804. Examples of cellulose acylate include commercially available products such as L-20, L-30, L-50, L-70, LT-55 (Daicel), CA-394-60LF (Eastman Chemical Company). It can also be used.

(Compound represented by the general formula 1)
The optical film of the present invention contains a compound represented by the following general formula 1.

In General Formula 1, X and Y each independently represent —N— or —CH—;
Q ₁ , Q ₂ and Q ₃ each independently represents a single bond or a divalent linking group;
R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a halogen group or a heterocyclic group.

When Q ₁ , Q ₂ and Q ₃ represent a divalent linking group, specific examples of the divalent linking group include —CH ₂ —, —CO—, —C (═O) O— *, —O. -, Or a combination thereof. * Indicates a bonding position with R ₁ , R ₂ or R ₃ .

When R ₁ , R ₂ and R ₃ are each an alkyl group, it is preferably 1 to 20 carbon atoms, more preferably 1 to 8 carbon atoms, and 1 to 4 carbon atoms. Is particularly preferred. When R ₁ , R ₂ and R ₃ are each an alkyl group, one or two or more carbon atoms which are not adjacent to each other are an oxygen atom, a sulfur atom, and a nitrogen atom (—NH— or —N (R) — (Wherein R includes an alkyl group having 1 to 8 carbon atoms) may be substituted with a heteroatom. For example, R ₁ , R ₂ and R ₃ may each be an alkylene (eg, ethylene, propylene) oxy group.
When R ₁ , R ₂ and R ₃ are each an alkenyl group, it is preferably 2 to 20 carbon atoms, more preferably 2 to 8 carbon atoms, and 2 to 4 carbon atoms. Is particularly preferred.
When R ₁ , R ₂ and R ₃ are each an alkynyl group, it is preferably 2 to 20 carbon atoms, more preferably 2 to 8 carbon atoms, and 2 to 4 carbon atoms. Is particularly preferred.

When R ₁ , R ₂ and R ₃ are each an aryl group, it is preferably 6 to 24 carbon atoms, more preferably 6 to 18 carbon atoms, and 6 to 10 carbon atoms. Is particularly preferable from the viewpoint of improving humidity dependency. Specifically, a phenyl group, 1-naphthyl group or 2-naphthyl group is preferable, and a phenyl group is particularly preferable.
When R ₁ , R ₂ and R ₃ are each halogen, fluorine, chlorine, bromine or iodine is preferred.
When R ₁ , R ₂ and R ₃ are each a heterocyclic group, it is preferably 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and 4 to 6 carbon atoms. It is particularly preferable from the viewpoint of improving humidity dependency. Specific examples include a pyrrolyl group, a pyrrolidino group, a pyrazolyl group, a pyrazolidino group, an imidazolyl group, a piperazino group, and a morpholino group.

R ₁ , R ₂ and R ₃ may be connected to form a ring. The ring formed may be a hydrocarbon ring or a heterocyclic ring. It is preferably a 5-membered ring or a 6-membered ring.

Each of R ₁ , R _2, and R ₃ may further have one or more substituents and may not have one, if possible. Examples of the substituent that each of R ₁ , R _2, and R ₃ may have include the following substituent group T.
Substituent group T:
An alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, an n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl, cyclohexyl group, etc.), alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12, more preferably 2 to 8). For example, a vinyl group, an allyl group, a 2-butenyl group, a 3-pentenyl group, etc.), an alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 2 carbon atoms). 8 such as propargyl group and 3-pentynyl group), aryl group (preferably having 6 to 30 carbon atoms, more preferred) 6 to 20, particularly preferably 6 to 12, and examples thereof include a phenyl group, a biphenyl group, and a naphthyl group.), An amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10, Particularly preferably 0 to 6, for example, amino group, methylamino group, dimethylamino group, diethylamino group, dibenzylamino group, etc.), alkoxy group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12, particularly preferably 1 to 8, for example, methoxy group, ethoxy group, butoxy group, etc.), aryloxy group (preferably 6-20 carbon atoms, more preferably 6-16, particularly Preferably they are 6-12, for example, a phenyloxy group, 2-naphthyloxy group etc. are mentioned), an acyl group (preferably carbon atom number). To 20, more preferably 1 to 16, particularly preferably 1 to 12, and examples thereof include an acetyl group, a benzoyl group, a formyl group, and a pivaloyl group), an alkoxycarbonyl group (preferably having 2 to 20 carbon atoms). , More preferably 2 to 16, particularly preferably 2 to 12, and examples thereof include a methoxycarbonyl group and an ethoxycarbonyl group.), An aryloxycarbonyl group (preferably having 7 to 20 carbon atoms, more preferably 7). -16, particularly preferably 7-10, for example, phenyloxycarbonyl group, etc.), acyloxy groups (preferably 2-20 carbon atoms, more preferably 2-16, particularly preferably 2-10). For example, acetoxy group, benzoyloxy group, etc.), acylamino group (preferably The number of carbon atoms is 2 to 20, more preferably 2 to 16, particularly preferably 2 to 10, and examples thereof include an acetylamino group and a benzoylamino group. ), An alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms such as a methoxycarbonylamino group), an aryloxycarbonylamino group ( Preferably it has 7 to 20 carbon atoms, more preferably 7 to 16 and particularly preferably 7 to 12, and examples thereof include a phenyloxycarbonylamino group, and a sulfonylamino group (preferably 1 to 20 carbon atoms). More preferably, it is 1-16, Most preferably, it is 1-12, for example, a methanesulfonylamino group, a benzenesulfonylamino group, etc.), a sulfamoyl group (preferably C0-20, more preferably 0). To 16, particularly preferably 0 to 12, such as sulfamoyl group, methyl Rufamoyl group, dimethylsulfamoyl group, phenylsulfamoyl group, etc.), carbamoyl group (preferably 1-20 carbon atoms, more preferably 1-16, particularly preferably 1-12, for example, Carbamoyl group, methylcarbamoyl group, diethylcarbamoyl group, phenylcarbamoyl group, etc.), alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16, particularly preferably 1 to 12, Methylthio group, ethylthio group, etc.), arylthio group (preferably 6-20 carbon atoms, more preferably 6-16, particularly preferably 6-12, such as phenylthio group). A sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16, Is preferably 1 to 12, for example, mesyl group, tosyl group, etc.), sulfinyl group (preferably 1 to 20 carbon atoms, more preferably 1 to 16, particularly preferably 1 to 12, For example, a methanesulfinyl group, a benzenesulfinyl group, etc.), a ureido group (preferably 1-20 carbon atoms, more preferably 1-16, particularly preferably 1-12, for example, a ureido group, a methylureido group). , Phenylureido groups, etc.), phosphoric acid amide groups (preferably having 1-20 carbon atoms, more preferably 1-16, particularly preferably 1-12, such as diethylphosphoric acid amide, phenylphosphoric acid Amide, etc.), hydroxy group, mercapto group, halogen atom (eg fluorine atom, chlorine atom, bromine atom) , Iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, heterocyclic group (preferably having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms). A hetero atom such as a nitrogen atom, an oxygen atom, a sulfur atom, specifically an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group, a piperidyl group, a morpholino group, a benzoxazolyl group, a benzimidazolyl group, Examples thereof include a benzthiazolyl group. ) And a silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms such as a trimethylsilyl group and a triphenylsilyl group).
These substituents may be further substituted. Moreover, when there are two or more substituents, they may be the same or different. If possible, they may be linked together to form a ring.

In the general formula 1, X is preferably —CH—, Y is preferably —N—, and Q ₁ and Q ₂ are preferably —CO—. In the general formula, it is more preferable that X is —CH—, Y is —N—, and Q ₁ and Q ₂ are —CO—.

  Specific examples of the compound represented by the general formula 1 include the following compounds P1 to P18.

The compound represented by general formula 1 can be synthesized, for example, according to the method described in WO2012 / 074050.
The content of the compound represented by Formula 1 in the optical film of the present invention is not particularly limited, but is preferably 5% by mass to 15% by mass, more preferably 5% by mass to 10% by mass, Preferably they are 6 mass% or more and 9 mass% or less.

(Polycondensed ester)
If desired, a polycondensation ester can be added to the optical film of the present invention.
The polycondensation ester is a polycondensation ester of a dicarboxylic acid component and a diol component. The dicarboxylic acid component may consist of only one dicarboxylic acid or may be a mixture of two or more dicarboxylic acids. Among these, as the dicarboxylic acid component, it is preferable to use a dicarboxylic acid component containing at least one aromatic dicarboxylic acid and at least one aliphatic dicarboxylic acid. On the other hand, the diol component may consist of only one diol component or a mixture of two or more diols. Among them, it is preferable to use ethylene glycol and / or an aliphatic diol having an average carbon atom number greater than 2.0 and 3.0 or less as the diol component.

    Examples of aromatic dicarboxylic acids include phthalic acid, terephthalic acid, isophthalic acid, 1,5-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,8-naphthalenedicarboxylic acid and 2,6-naphthalenedicarboxylic acid and the like are included, and phthalic acid and terephthalic acid are preferable. Examples of aliphatic dicarboxylic acids include oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, and 1,4 -Cyclohexane dicarboxylic acid etc. are contained, and a succinic acid and adipic acid are preferable among these.

  From the viewpoint of optical developability in the polycondensed ester, 50 mol% or more of the dicarboxylic acid component is preferably a terephthalic acid component, and from the viewpoint of handling properties, 50 mol% to 90 mol% is further a terephthalic acid component. preferable.

  The diol component is ethylene glycol and / or a diol having an average number of carbon atoms of more than 2.0 and 3.0 or less. In the diol component, ethylene glycol is preferably 50 mol%, and more preferably 75 mol%. Examples of the aliphatic diol include alkyl diols and alicyclic diols, such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, and 1,3-butane. Diol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2,2-diethyl -1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane), 3-methyl-1,5 -Pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexa There are diol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-octadecanediol, diethylene glycol and the like, and these are one or more kinds together with ethylene glycol. It is preferably used as a mixture of

  The diol component is preferably ethylene glycol, 1,2-propanediol, and 1,3-propanediol, and particularly preferably ethylene glycol and 1,2-propanediol.

  Further, the polycondensed ester is preferably a derivative of a polycondensed ester in which the terminal OH of the polycondensed ester forms an ester with a monocarboxylic acid. Monocarboxylic acids used for sealing the both terminal OH groups are preferably aliphatic monocarboxylic acids, preferably acetic acid, propionic acid, butanoic acid, benzoic acid and derivatives thereof, more preferably acetic acid or propionic acid, and acetic acid. Most preferred. When the number of carbon atoms of the monocarboxylic acids used at both ends of the polycondensed ester is 3 or less, the loss on heating of the compound does not increase, and the occurrence of planar failures can be reduced. Moreover, 2 or more types of monocarboxylic acid used for sealing may be mixed. Both ends of the polycondensed ester are preferably sealed with acetic acid or propionic acid, and derivatives of the polycondensed ester in which both ends are acetyl ester residues due to acetic acid sealing are particularly preferred.

  The number average molecular weight of the polycondensed ester is preferably 500 to 2000, more preferably 700 to 1500, and particularly preferably 700 to 1200. The number average molecular weight of the polycondensed ester is preferably 500 or more from the viewpoint of improving optical expression. Moreover, if it is 2000 or less, compatibility with a cellulose acylate will become high and it will become difficult to produce the bleed out at the time of manufacture and the time of heat-stretching.

  The number average molecular weight of the polycondensed ester can be measured and evaluated by gel permeation chromatography as described above in the present specification. Further, in the case of a polyester polyol having an unsealed terminal, it can also be calculated from the amount of hydroxyl group per mass (hereinafter referred to as hydroxyl value). The hydroxyl value is determined by measuring the amount (mg) of potassium hydroxide required for neutralizing excess acetic acid after acetylating the polyester polyol.

  The polycondensation ester is a conventional method, either a hot melt condensation method using a polyesterification reaction or transesterification reaction between a dicarboxylic acid component and a diol component, or an interfacial condensation method between an acid chloride of a dicarboxylic acid component and a glycol. Can be easily synthesized. The polycondensation ester is described in detail in Koichi Murai, “Plasticizers, Theory and Applications” (Koshobo Co., Ltd., first published on March 1, 1973). In addition, Japanese Patent Laid-Open Nos. 05-155809, 05-155810, Japanese Patent Laid-Open Nos. 05-97073, 2006-259494, 07-330670, 2006-342227, 2007-003679. It is also possible to use materials described in the above publications.

As a specific example of the polycondensed ester,
Polycondensed ester having a number average molecular weight of 1000, wherein the dicarboxylic acid unit is terephthalic acid / succinic acid = 70/30, the diol unit is ethylene glycol / propylene glycol = 50/50, and the terminal is an acetyl group;
A dicarboxylic acid unit is terephthalic acid / succinic acid = 45/55, a diol unit is ethylene glycol / propylene glycol = 50/50, a polycondensed ester having a number average molecular weight of 950 having an acetyl group at the end; and a dicarboxylic acid unit is terephthalic acid = 100, a polycondensed ester having a number average molecular weight of 800 having a diol unit of ethylene glycol / propylene glycol = 50/50 and a terminal having an acetyl group can be used. The numerical values of dicarboxylic acid and diol indicate the molar ratio.

The optical film of the present invention preferably contains 1 to 9 parts by mass of a polycondensed ester (preferably, a polycondensed ester of an aromatic dicarboxylic acid and an aliphatic diol) with respect to 100 parts by mass of cellulose acylate. 7 mass parts is more preferable, and 1-5 mass parts is still more preferable. By controlling the amount of polycondensation ester added within the above range, the diffusion of antistatic agents and trace amounts of acid components contained in adhesives is suppressed, and changes in cross transmittance on the long wave side at high temperatures and high humidity Can be more effectively suppressed, which is preferable.
In the present invention, the polycondensed ester can be used as a plasticizer, but the polycondensed ester may also serve as a retardation developer.

(Durability improver)
The optical film of the present invention may contain a compound represented by the following general formula 2.

In general formula 2, R ¹¹ , R ¹³ and R ¹⁵ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group or an aromatic group. The alkyl group, cycloalkyl group, alkenyl group and aromatic group may have a substituent. However, any one of R ¹¹ , R ¹³ and R ¹⁵ is an alkyl group or a cycloalkyl group substituted by a group having a ring structure, and the ring structures present in R ¹¹ , R ¹³ and R ¹⁵ are the total 3 or more.

1-20 are preferable, as for carbon number of the alkyl group in said R <^11> , R <^13> and R < ¹⁵ >, 1-10 are more preferable, 1-5 are still more preferable, 1-3 are especially preferable, especially a methyl group or ethyl Groups are preferred. However, in the case of an alkyl group substituted by a group having a ring structure, the carbon number is preferably 7 to 20, more preferably 7 to 12, and still more preferably 7 to 10. The ring structure in the alkyl group having a ring structure may be an aromatic ring (including an aromatic heterocyclic ring) or an aliphatic ring, but is preferably an aromatic hydrocarbon group or an aliphatic ring. .
The number of carbon atoms of the cycloalkyl groups represented by R ^11, R ¹³ and R ^15, preferably from 3 to 20, more preferably from 3 to 10, more preferably 4 to 8, 5 or 6 is particularly preferred. Specific examples of the cycloalkyl group include, for example, cyclopropyl, cyclopentyl, and cyclohexyl, and cyclohexyl is particularly preferable.
2-20 are preferable, as for carbon number of the alkenyl group in said R < ¹¹ >, R < ¹³ > and R < ¹⁵ >, 2-10 are more preferable, and 2-5 are more preferable. For example, vinyl and allyl are mentioned.
The aromatic group in R ¹¹ , R ¹³ and R ¹⁵ may be an aromatic hydrocarbon group or an aromatic heterocyclic group, but is preferably an aromatic hydrocarbon group. 6-20 are preferable, as for carbon number of an aromatic group, 6-16 are more preferable, and 6-12 are more preferable.
As the aromatic group, especially the aromatic hydrocarbon group, phenyl and naphthyl are preferable, and phenyl is more preferable.

Each of the above groups for R ¹¹ , R ¹³ and R ¹⁵ may have a substituent. The substituent is not particularly limited, and may be an alkyl group (preferably having 1 to 10 carbon atoms such as methyl, ethyl, isopropyl, t-butyl, pentyl, heptyl, 1-ethylpentyl, benzyl, 2-ethoxyethyl, 1-carboxymethyl and the like), alkenyl groups (preferably having 2 to 20 carbon atoms, such as vinyl, allyl, oleyl and the like), alkynyl groups (preferably having 2 to 20 carbon atoms, such as ethynyl, butadiynyl, phenylethynyl and the like) ), A cycloalkyl group (preferably having 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, etc.), an aryl group (preferably having 6 to 26 carbon atoms, such as phenyl, 1-naphthyl, etc. 4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl, etc.), Terocyclic group (preferably a heterocyclic group having 0 to 20 carbon atoms, wherein the ring-forming heteroatom is preferably an oxygen atom, a nitrogen atom or a sulfur atom, and is a 5- or 6-membered ring fused with a benzene ring or a heterocyclic ring. The ring may be a saturated ring, an unsaturated ring, or an aromatic ring. For example, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, 2-imidazolyl, 2-benzimidazolyl, 2-thiazolyl, 2-oxazolyl Etc.), alkoxy groups (preferably having 1 to 20 carbon atoms, such as methoxy, ethoxy, isopropyloxy, benzyloxy, etc.), aryloxy groups (preferably having 6 to 26 carbon atoms, such as phenoxy, 1-naphthyloxy, etc.) , 3-methylphenoxy, 4-methoxyphenoxy, etc.),

An alkylthio group (preferably having 1 to 20 carbon atoms, such as methylthio, ethylthio, isopropylthio, benzylthio, etc.), an arylthio group (preferably having 6 to 26 carbon atoms, such as phenylthio, 1-naphthylthio, 3-methylphenylthio, etc. , 4-methoxyphenylthio, etc.), sulfonyl groups (preferably alkyl or aryl sulfonyl groups, preferably having 1 to 20 carbon atoms, such as methylsulfonyl, ethylsulfonyl, benzenesulfonyl, toluenesulfonyl, etc.), acyl groups ( Including alkylcarbonyl group, alkenylcarbonyl group, arylcarbonyl group, and heterocyclic carbonyl group, carbon number is preferably 20 or less, for example, acetyl, pivaloyl, acryloyl, methacryloyl, benzoyl, nicotinoyl, etc.), alkoxy Rubonyl group (preferably having 2 to 20 carbon atoms, for example, ethoxycarbonyl, 2-ethylhexyloxycarbonyl, etc.), aryloxycarbonyl group (preferably having 7 to 20 carbon atoms, for example, phenyloxycarbonyl, naphthyloxycarbonyl, etc.) An amino group (including an amino group, an alkylamino group, an arylamino group and a heterocyclic amino group, preferably having 0 to 20 carbon atoms, such as amino, N, N-dimethylamino, N, N-diethylamino, N- Ethylamino, anilino, 1-pyrrolidinyl, piperidino, morpholinyl, etc.), sulfonamide groups (preferably alkyl or aryl sulfonamide groups, preferably having 0 to 20 carbon atoms, for example, N, N-dimethylsulfonamide, N -Phenylsulfonamide etc.), sulfamoyl group Preferably, it is an alkyl or aryl sulfamoyl group, preferably having 0 to 20 carbon atoms, such as N, N-dimethylsulfamoyl, N-phenylsulfamoyl, etc.), an acyloxy group (preferably having 1 to 20 carbon atoms). , For example, acetyloxy, benzoyloxy, etc.), carbamoyl groups (preferably alkyl or aryl carbamoyl groups, preferably having 1 to 20 carbon atoms, such as N, N-dimethylcarbamoyl, N-phenylcarbamoyl, etc.), acylamino Group (preferably having 1 to 20 carbon atoms, for example, acetylamino, acryloylamino, benzoylamino, nicotinamide, etc.), cyano group, hydroxy group, mercapto group or halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine) Atoms).

  The above substituent may be further substituted with the above substituent. Examples thereof include a perfluoroalkyl group such as trifluoromethyl, an aralkyl group, and an alkyl group substituted with an acyl group.

Here, among the above substituents that each of R ¹¹ , R ¹³ and R ¹⁵ may have, an alkyl group, an aryl group, an alkoxy group, an alkylthio group, an alkylsulfonyl group, a halogen atom, and an acyl group are preferable. , An alkyl group, an aryl group, an alkoxy group, and an acyl group are more preferable, and an alkyl group and an alkoxy group are more preferable.

The compound represented by the general formula 2 is an alkyl group or a cycloalkyl group in which any one of R ¹¹ , R ¹³ and R ¹⁵ is substituted with a group having a ring structure, and any one of them is a group having a ring structure. Is preferably a substituted alkyl group.
Of these, R ¹⁵ is preferably an alkyl group or a cycloalkyl group substituted with a group having a ring structure.
Here, the ring of the group having a ring structure is a benzene ring, naphthalene ring, cyclopentane ring, cyclohexane ring, nitrogen-containing heteroaromatic ring (for example, pyrrole ring, pyrazole ring, imidazole ring, oxazole ring, thiazole ring, pyridine ring) , Indole ring and isoindole ring) are preferable.
In the compound represented by the general formula 2, at least two of R ¹¹ , R ¹³ and R ¹⁵ are preferably an alkyl group or a cycloalkyl group having a ring structure as a substituent. Furthermore, it is more preferable that R ¹¹ and R ¹³ are each independently an alkyl group which may have a substituent, an aromatic group which may have a substituent, or a cycloalkyl group.
In the compound represented by the general formula 2, it is more preferable that the total of the ring structures present in the substituents of R ¹¹ , R ¹³ and R ¹⁵ is at most 4.

R ¹⁵ is preferably an alkyl group or a cycloalkyl group that may be substituted by a ring structure group or an acyl group, an alkyl group substituted by an aryl group, an alkyl group substituted by an acyl group (preferably an acyl group and an aryl group) Is more preferably an alkyl group substituted with an aryl group or a cycloalkyl group.
Hereinafter, the preferable alkyl group and cycloalkyl group in R ¹⁵ will be further described.

Among the alkyl groups, examples of the unsubstituted alkyl group include methyl, ethyl, propyl, isopropyl, n-butyl, n-hexyl, 2-ethylhexyl, and n-octyl.
Examples of the alkyl group substituted with a ring structure group include aralkyl groups such as benzyl, phenethyl, 3-phenylpropyl, naphthylmethyl, pyridin-2-ylmethyl, pyridin-3-ylmethyl, pyridin-4-ylmethyl, and indole- 3-ylmethyl is mentioned.

The acyl group in the alkyl group substituted with an acyl group is preferably an alkylcarbonyl group, a cycloalkylcarbonyl group, or an arylcarbonyl group, more preferably a cycloalkylcarbonyl group or an arylcarbonyl group having a ring structure, particularly an arylcarbonyl group. preferable.
Examples of the alkylcarbonyl group include acetyl, propionyl, butyryl, and pivaloyl. Examples of the cycloalkylcarbonyl group include cyclopropylcarbonyl, cyclopentylcarbonyl, and cyclohexylcarbonyl. Examples of the arylcarbonyl group include, for example, , Benzoyl, toluoyl and naphthoyl.
Examples of the alkyl group substituted with an acyl group include a 2-acylethyl group, a 3-acylpropyl group, and a 2-acylpropyl group, with a 2-acylethyl group being preferred.
In the present invention, the alkyl group substituted with an acyl group is preferably an alkyl group substituted with an aryl group together with an acyl group. In this case, the aryl group is preferably a phenyl group.
Examples of the alkyl group substituted with an acyl group and an aryl group include 1-phenyl-2-benzoylethyl and 1-tolyl-2-benzoylethyl.

Examples of the cycloalkyl group include the groups exemplified for R ¹¹ , R ¹³ and R ¹⁵ .

Although the mechanism is not clear, it is considered that the absorption wavelength of the compound represented by the general formula 2 is shortened by suppressing the expansion of the conjugated structure by R ¹⁵ . By setting it as such a compound, the adhesiveness of an ultraviolet curable adhesive is not impaired.

Among the compounds represented by the general formula 2, preferred compounds are listed as follows.
-A compound in which any one of R ¹¹ , R ¹³ and R ¹⁵ is an alkyl group substituted with an aromatic ring In addition, among alkyl groups substituted with an aromatic ring, one or two aryl groups in the alkyl group Preferred is a group substituted (when two aryl groups are substituted, it is preferably substituted on the same carbon atom). Further, an alkyl group substituted with an aryl group and an acyl group (preferably an aryloyl group) is also preferable.
A compound in which any one of R ¹¹ , R ¹³ and R ¹⁵ is a group containing a cycloalkyl group, and preferably the group containing a cycloalkyl group is a cycloalkyl group

In the ring structure in the case where “the total number of ring structures present in R ¹¹ , R ¹³ and R ¹⁵ is 3 or more”, the basic skeleton itself of the substituent of R ¹¹ , R ¹³ and R ¹⁵ has a ring structure. In addition to the cases, as already exemplified, a form in which the substituents of R ¹¹ , R ¹³ and R ¹⁵ have a ring structure is also included.
The ring structure is preferably a cyclic saturated hydrocarbon structure or an aromatic ring structure (aromatic hydrocarbon structure or aromatic heterocyclic structure). The ring structure may be a condensed ring structure.
When the ring structure is a cyclic saturated hydrocarbon structure, the cyclic saturated hydrocarbon structure is preferably present as a cycloalkyl group having 3 to 20 carbon atoms. More specifically, it is more preferably present as a cyclopropyl group, a cyclopentyl group or a cyclohexyl group, and particularly preferably as a cyclohexyl group.
Moreover, when the said ring structure is an aromatic ring structure, it is preferable that it is an aromatic hydrocarbon structure. The aromatic hydrocarbon structure preferably exists as an aryl group having 6 to 20 carbon atoms. More specifically, it is more preferably present as a phenyl group or a naphthyl group, and particularly preferably as a phenyl group.
The ring structure may have a substituent, but is preferably unsubstituted. When it has a substituent, the preferable range is the same as the substituent which each group of R ¹¹ , R ¹³ and R ¹⁵ may have.

In the compound represented by the general formula 2, R ¹¹ , R ¹³ and R ¹⁵ are more preferably an alkyl group, an alkenyl group or an aryl group. R ¹¹ , R ¹³ and R ¹⁵ each preferably have one or more ring structures, and more preferably each have one ring structure.

The molecular weight of the compound represented by Formula 2 is preferably 250 to 1200, more preferably 300 to 800, and particularly preferably 350 to 600.
By making molecular weight into such a preferable range, the compound represented by General formula 2 will be excellent in suppression of volatilization from a film, and a highly transparent film can be obtained.

  Specific examples of the compound represented by Formula 2 are shown below, but the present invention is not limited thereto.

It is known that the compound represented by the general formula 2 can be synthesized using a synthesis method of barbituric acid in which a urea derivative and a malonic acid derivative are condensed. Barbituric acid having two substituents on the nitrogen atom can be obtained by heating N, N 'disubstituted urea and malonic acid chloride, or by heating in combination with an activator such as malonic acid and acetic anhydride. For example, Journal of the American Chemical Society, 61, 1015 (1939), Journal of Medicinal Chemistry, 54, 2409 (2011), Tetrahedron 99, 80 The method described in International Publication No. 2007/150011 pamphlet and the like can be preferably used.
In addition, the malonic acid used for the condensation may be unsubstituted or has a substituent. When malonic acid having a substituent corresponding to R ¹⁵ is used, barbituric acid is represented by the general formula 2. Can be synthesized. In addition, when an unsubstituted malonic acid and a urea derivative are condensed, a 5-position unsubstituted barbituric acid is obtained. By modifying this, a compound represented by the general formula 2 may be synthesized.

As a method for modifying the 5-position, an addition reaction such as a nucleophilic substitution reaction with an alkyl halide or the like or a Michael addition reaction can be used. In addition, a method in which an alkylidene or arylidene compound is produced by dehydration condensation with an aldehyde or a ketone and then a double bond is reduced can be preferably used. For example, a reduction method using zinc is described in Tetrahedron Letters, 44, 2203 (2003), and a reduction method using catalytic reduction is Tetrahedron Letters, 42, 4103 (2001) or Journal of the American Chemical, 119, 12849 (1997), a reduction method using NaBH ₄ is described in Tetrahedron Letters, 28, 4173 (1987), etc., respectively. These are all synthetic methods that can be preferably used in the case of having an aralkyl group at the 5-position or a cycloalkyl group.
The method for synthesizing the compound represented by Formula 2 used in the present invention is not limited to the above.

Although the content in the optical film of the compound represented by General Formula 2 is not particularly limited, it is preferably 0.1 to 20 parts by mass, and 0.2 to 15 parts by mass with respect to 100 parts by mass of cellulose acylate. It is more preferable that it is 0.3-10 mass parts. By making the addition amount of the compound represented by the general formula 2 in the above range, it is possible to effectively reduce the moisture permeability and suppress the generation of haze.
In the case of co-casting, an embodiment in which the compound represented by the general formula 2 is added only to the skin layer is also preferably used in terms of adjusting the optical characteristics. The preferable range of the content when added only to the skin layer is the same as the above content.

  The scope of the present invention includes an optical film to which the compound represented by the general formula 2 is added in the form of a hydrate, a solvate or a salt. In the present invention, the hydrate may contain an organic solvent, and the solvate may contain water. That is, “hydrate” and “solvate” include mixed solvates containing both water and organic solvents.

Examples of the solvent included in the solvate include any common organic solvent. Specifically, alcohol (for example, methanol, ethanol, 2-propanol, 1-butanol, 1-methoxy-2-propanol, t-butanol), ester (for example, ethyl acetate), hydrocarbon (aliphatic or aromatic) Any of hydrocarbons may be used, and examples thereof include toluene, hexane, heptane), ether (eg, diethyl ether, tetrahydrofuran), nitrile (eg, acetonitrile), ketone (eg, acetone, 2-butanone) and the like. Preferred are alcohol solvates, and more preferred are methanol, ethanol, 2-propanol, and 1-butanol. These solvents may be a reaction solvent used in the synthesis of the compound represented by the general formula 2, a solvent used in the crystallization purification after synthesis, or a mixture thereof. Also good.
Two or more kinds of solvents may be included at the same time, or water and a solvent (for example, water and alcohol (for example, methanol, ethanol, t-butanol), etc.) may be used.

  Salts include acid addition salts formed with inorganic or organic acids. Examples of the inorganic acid include hydrohalic acid (hydrochloric acid, hydrobromic acid), sulfuric acid, phosphoric acid and the like. Examples of organic acids include acetic acid, trifluoroacetic acid, oxalic acid, and citric acid. Alkanesulfonic acid (methanesulfonic acid), arylsulfonic acid (benzenesulfonic acid, 4-toluenesulfonic acid, 1,5-naphthalenedisulfonic acid) Acid).

  A salt may also have an acidic moiety present in the parent compound such as a metal ion (eg, an alkali metal salt, such as a sodium or potassium salt, an alkaline earth metal salt, such as a calcium or magnesium salt, an ammonium salt, an alkali metal ion, alkaline earth Examples include, but are not limited to, salts formed when substituted with metal ions or aluminum ions, or prepared with organic bases (ethanolamine, diethanolamine, triethanolamine, morpholine, piperidine). Of these, sodium salts and potassium salts are preferred.

<Other additives>
If necessary, a matting agent can be added to the optical film of the present invention. The matting agent is not particularly limited as long as it is a material exhibiting a function of preventing scratches during handling or deterioration of transportability, and an inorganic compound or an organic compound matting agent can be used.
Preferred specific examples of the inorganic compound matting agent include silicon-containing inorganic compounds (eg, silicon dioxide, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, etc.), titanium oxide, zinc oxide, Aluminum oxide, barium oxide, zirconium oxide, strongtium oxide, antimony oxide, tin oxide, tin oxide / antimony, calcium carbonate, talc, clay, calcined kaolin, calcium phosphate, etc. are preferred, and more preferably inorganic compounds containing silicon and zirconium oxide However, since the turbidity of the cellulose acylate film can be reduced, silicon dioxide is particularly preferably used. As the silicon dioxide fine particles, for example, commercially available products having a trade name such as Aerosil (registered trademark) R972, R974, R812, 200, 300, R202, OX50, TT600 (above Nippon Aerosil Co., Ltd.) can be used. . As the fine particles of zirconium oxide, for example, those commercially available under trade names such as Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) can be used.

  Preferable specific examples of the organic compound matting agent are, for example, polymers such as silicone resin, fluorine resin and acrylic resin, and among them, silicone resin is preferably used. Among silicone resins, those having a three-dimensional network structure are particularly preferable. For example, Tospearl (registered trademark) 103, Tospearl 105, Tospearl 108, Tospearl 120, Tospearl 145, Tospearl 3120, and Tospearl 240 (above Toshiba Silicone Co., Ltd.) A commercial product having a trade name such as “made” can be used.

  The method for adding the matting agent to the cellulose acylate solution is not particularly limited. For example, an additive may be contained at the stage of mixing cellulose acylate and a solvent, or an additive may be added after preparing a mixed solution with cellulose acylate and a solvent. Furthermore, a matting agent may be added and mixed immediately before casting the dope, and the mixing can be performed by installing a screw type mixer on-line. Specifically, a static mixer such as an in-line mixer is preferable, and as the in-line mixer, for example, a static mixer SWJ (Toray static type in-pipe mixer Hi-Mixer) (manufactured by Toray Engineering) or the like is preferable. A preferable mode of mixing the matting agent is as described in paragraph No. 0127 of JP2013-75401A.

  The optical film of the present invention contains a matting agent in at least one of the two skin layers, and is resistant to scratches by reducing the coefficient of friction on the film surface. From the viewpoint of preventing film breakage, it is particularly preferable to contain a matting agent in both of the two skin layers from the viewpoint of effectively reducing scratch resistance and creaking.

  The content of the matting agent in the optical film of the present invention is preferably 0.01 to 5.0% by mass, more preferably 0.03 to 3.0% by mass, and particularly preferably 0.05 to 1.0% by mass. By setting it as the above range, it is possible to realize the effect of reducing creaking and scratch resistance without increasing the haze of the optical film.

[Method for producing optical film]
The method for producing an optical film of the present invention includes a film forming step of casting a dope containing cellulose acylate, calcium and the compound represented by the general formula 1 on a support. The formed film may be peeled from the support and the peeled film may be stretched.

(Preparation of dope)
In the present invention, an optical film can be produced using a solution (dope) obtained by dissolving cellulose acylate in an organic solvent by a solution casting method.
The organic solvent is a solvent selected from ethers having 3 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, esters having 3 to 12 carbon atoms, and halogenated hydrocarbons having 1 to 6 carbon atoms. It is preferable to contain. The ether, ketone and ester may have a cyclic structure. A compound having two or more functional groups of ether, ketone and ester (that is, —O—, —CO— and —COO—) can also be used as the organic solvent. The organic solvent may have another functional group such as an alcoholic hydroxyl group. In the case of an organic solvent having two or more types of functional groups, the number of carbon atoms may be within the specified range of the compound having any functional group.

Examples of the ether having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole.
Examples of the ketone having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclohexanone and methylcyclohexanone.
Examples of the ester having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.
The number of carbon atoms of the halogenated hydrocarbon is preferably 1 or 2, and most preferably 1. The halogen of the halogenated hydrocarbon is preferably chlorine. The proportion of halogen atoms substituted by halogen in the halogenated hydrocarbon is preferably 25 to 75 mol%, more preferably 30 to 70 mol%, and more preferably 35 to 65 mol%. More preferably, it is most preferable that it is 40-60 mol%. Methylene chloride is a representative halogenated hydrocarbon.
Two or more organic solvents may be mixed and used.

  The solution can be prepared by using a dope preparation method and apparatus in a normal solution casting method. In the case of a general method, it is preferable to use a halogenated hydrocarbon (particularly, methylene chloride) as the organic solvent.

The amount of cellulose acylate is preferably adjusted so as to be contained in the obtained solution in an amount of 10 to 40% by mass, and more preferably 10 to 30% by mass. Arbitrary additives may be added to the organic solvent.
The solution can be prepared by stirring the cellulose acylate and the organic solvent at room temperature (0 to 40 ° C.). High concentration solutions may be stirred under pressure and heating conditions. Specifically, the cellulose acylate and the organic solvent are placed in a pressure vessel and sealed, and stirred while being heated to a temperature equal to or higher than the boiling point of the solvent at normal temperature and in a range where the solvent does not boil. The heating temperature is usually 40 ° C. or higher, preferably 60 to 200 ° C., and more preferably 80 to 110 ° C.

Each component may be roughly mixed in advance and then put into a container, or may be put into a container sequentially. The container needs to be configured so that it can be stirred. The container can be pressurized by injecting an inert gas such as nitrogen gas. Moreover, you may utilize the raise of the vapor pressure of the solvent by heating. Or after sealing a container, you may add each component under pressure.
When heating, it is preferable to heat from the outside of the container. For example, a jacket type heating device can be used. The entire container can also be heated by providing a plate heater outside the container and piping to circulate the liquid.
It is preferable to provide a stirring blade inside the container and stir using this. The stirring blade preferably has a length that reaches the vicinity of the wall of the container. A scraping blade is preferably provided at the end of the stirring blade in order to renew the liquid film on the vessel wall.
Instruments such as a pressure gauge and a thermometer may be installed in the container. Each component is dissolved in a solvent in a container. The prepared dope may be taken out of the container after cooling, or may be cooled using a heat exchanger or the like after taking out.

(Casting)
A cellulose acylate film can be produced from the prepared cellulose acylate solution (dope) by a solution casting method.
The dope is cast on a drum or band and the solvent is evaporated to form a film. The concentration of the dope before casting is preferably adjusted so that the solid content is 13 to 35% by mass. The surface of the drum or band is preferably finished in a mirror state. Regarding casting and drying methods in the solution casting method, US Pat. No. 2,336,310, US Pat. No. 2,367,603, US Pat. No. 2,429,078, US Pat. No. 2,429,297, US Pat. No. 2,429,978, US Pat. No. 2,607,704, US Japanese Patent No. 2739069, US Patent No. 2739070, British Patent No. 640731, British Patent No. 736892, Japanese Patent Publication No. 45-4554, Japanese Patent Publication No. 49-5614, Japanese Patent Publication No. Sho 60-176634, Japanese Patent Publication There are descriptions in JP-A-60-203430 and JP-A-62-115035.

  In the present invention, the obtained cellulose acylate solution (dope) can be cast on a smooth band or drum as a support to form a film.

  In the present invention, a core layer forming dope containing cellulose acylate, calcium and a compound represented by the general formula 1 and a skin layer forming dope containing cellulose acylate can be co-cast on a support. preferable. In this case, the calcium content with respect to the cellulose acylate mass in the core layer forming dope is more preferably larger than the calcium content with respect to the cellulose acylate mass in the skin layer forming dope.

  As a method for producing the optical film of the present invention, a known casting method (preferably a co-casting method) can be used. For example, a film may be produced by laminating and laminating cellulose acylate solutions from a plurality of casting ports provided at intervals in the traveling direction of the metal support. For example, JP-A 61-158414 The methods described in JP-A-1-122419, JP-A-11-198285, and the like can be used. Alternatively, a film may be formed by casting a cellulose acylate solution from two casting ports. For example, JP-B-60-27562, JP-A-61-94724, JP-A-61-947245. It can be carried out by the methods described in JP-A No. 61-104413, JP-A No. 61-158413, and JP-A No. 6-134933. Further, a cellulose acylate in which a flow of a high-viscosity cellulose acylate solution described in JP-A-56-162617 is wrapped with a low-viscosity cellulose acylate solution and the high-viscosity and low-viscosity cellulose acylate solutions are simultaneously extruded. A film casting method may be used. Further, it is also preferable that the outer solution described in JP-A-61-94724 and JP-A-61-94725 contains a larger amount of an alcohol component which is a poor solvent than the inner solution.

Further, by using two casting ports, the film cast on the metal support by the first casting port is peeled off, and the second casting is performed on the side that is in contact with the metal support surface, thereby the film. Can also be produced (for example, Japanese Patent Publication No. 44-20235).
The dope cast as described above can be dried and peeled off from the support as a film.

(Drying process)
A method for drying a film that has been dried on a drum or belt and peeled off will be described. The film peeled off at the peeling position immediately before the drum or belt makes one round is conveyed by alternately passing through a group of rolls arranged in a staggered manner, or both ends of the peeled film are held by clips or the like. It is transported by a non-contact transport method. Drying can be performed by a method of applying wind at a predetermined temperature to both sides of the film being conveyed or a method using a heating means such as a microwave. Since rapid drying may impair the flatness of the film to be formed, it is preferable to dry at a temperature at which the solvent does not foam in the initial stage of drying, and to dry at a high temperature after the drying proceeds. In the drying process after peeling from the support, the film tends to shrink in the longitudinal direction or the width direction by evaporation of the solvent. Shrinkage increases with drying at higher temperatures. Drying while suppressing this shrinkage as much as possible is preferable for improving the flatness of the film. From this point, for example, as shown in Japanese Patent Laid-Open No. 62-46625, a method in which all or part of the drying process is performed while holding the width at both ends of the web with clips or pins in the width direction. (Tenter method) is preferable. It is preferable that the drying temperature in the said drying process is 100-145 degreeC. Although the drying temperature, the amount of drying air, and the drying time differ depending on the solvent used, it may be appropriately selected according to the type and combination of the solvents used.

(Stretching)
In the present invention, after the co-cast dope is dried and peeled from the support, the film can be stretched.
In the method for producing a cellulose acylate film, the cellulose acylate film may be stretched in any direction of a film transport direction (hereinafter also referred to as MD) and a direction orthogonal to the film transport direction (hereinafter also referred to as TD). Stretching is preferable from the viewpoint of developing a desired retardation. Stretching may be performed in one stage or in multiple stages. When performing biaxial stretching, it is preferable to stretch in the TD direction after stretching in the film MD direction.

The stretching ratio in stretching to MD is preferably 0 to 20%, more preferably 0 to 15%, and particularly preferably 0 to 10%. The stretching rate (elongation) of the cellulose acylate web during the stretching can be achieved by the difference in peripheral speed between the metal support speed and the stripping speed (stripping roll draw). For example, when an apparatus having two nip rolls is used, the cellulose acylate film can be preferably stretched in the MD by increasing the rotation speed of the nip roll on the outlet side rather than the rotation speed of the nip roll on the inlet side. By performing such stretching, the expression of retardation can be adjusted.
Here, the “stretch ratio” means that obtained by the following formula.
Stretch ratio = 100 × {(length after stretching) − (length before stretching)} / length before stretching

The stretching ratio in stretching in the TD direction is preferably more than 20%, more preferably more than 20% to 60% or less, particularly preferably 25 to 55%, and more preferably 25 to 50%. More particularly preferred.
The temperature at the start of stretching is preferably 100 ° C. or higher and 220 ° C. or lower, and more preferably 120 ° C. or higher and 200 ° C. or lower.
In the present invention, it is preferable to stretch using a tenter device as a method of stretching in a direction perpendicular to the film conveying direction.
When stretching in the TD direction, the residual solvent amount of the film at the start of stretching is preferably 0% by mass or more and 3% by mass or less, more preferably 0% by mass or more and 2.3% by mass or less. More preferably, it is at least 2.1% by mass.
The amount of residual solvent can be expressed by the following formula.
Residual solvent amount (% by mass) = {(MN) / N} × 100
Here, M is the mass of the film (web) at an arbitrary point in time, and N is the mass when the film whose M is measured is dried at 110 ° C. for 3 hours.

[Polarizer]
The optical film of the present invention can be used as a polarizing plate film. The polarizing plate can be produced by laminating and laminating the optical film of the present invention on at least one surface of the polarizer. A conventionally well-known thing can be used for a polarizer, For example, hydrophilic polymer films, such as a polyvinyl alcohol film, are processed with a dichroic dye like iodine, and are extended. The bonding of the cellulose acylate film and the polarizer is not particularly limited, but can be performed with an adhesive made of an aqueous solution of a water-soluble polymer. The water-soluble polymer adhesive is preferably a completely saponified polyvinyl alcohol aqueous solution. Although the thickness of a polarizer is not specifically limited, Generally, it is 3 micrometers-35 micrometers, Preferably it is 5 micrometers-25 micrometers, More preferably, it is 5-20 micrometers.

The optical film of the present invention is composed of protective film / polarizer / protective film / liquid crystal cell / optical film of the present invention / polarizer / protective film, or protective film / polarizer / optical film of the present invention / liquid crystal cell / present. It can be preferably used in the constitution of the optical film / polarizer / protective film of the invention.
In particular, it is preferable that an anti-glare layer is coated on the viewing side of the protective film used on the outermost surface. By providing an antiglare layer on the viewing side, it is possible to suppress a decrease in the degree of polarization after storage at high temperature and high humidity. It is preferable to apply the antiglare layer before processing the polarizing plate because the production process can be simplified. Regarding the coating method of the antiglare layer, for example, the method described in JP2013-228720A can be used, but the method is not limited to this description, and a known antiglare layer can be used.

  As the protective film, any film can be used as long as it has a function as a polarizing plate protective film. As a material constituting the polarizing plate protective film, for example, a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy and the like is used. Specific examples of such thermoplastic resins include cellulose resins such as triacetyl cellulose, polyester resins, polyethersulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, (meth) acrylic resins, cyclic Examples thereof include polyolefin resins (norbornene resins), polyarylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures thereof. In addition, a polarizing plate protective film is usually bonded to the polarizer by an adhesive layer.

(Haze change of polarizing plate with antiglare layer at high temperature and high humidity)
A polarizing plate having an antiglare layer may adversely affect the optical film when left for a long time under high temperature and high humidity due to the influence of an initiator remaining in a small amount in the antiglare layer. It has been found that the films of the examples and comparative examples of the present application increase in haze when left for a long period of time under ultra-high temperature and high humidity.
It has been found that the haze increase can be suppressed when the support surface of the optical film is bonded to the polarizer surface or when a film containing the durability improver is used. Although the mechanism is unknown, it is estimated that the reaction to the vicinity of the film can be suppressed by suppressing the transfer of the initiator to the optical film.

(Wave curl on polarizing plate)
The curl is the end of the polarizing plate when the polarizing plate laminated in the order of the protective film, protective film, polarizer, optical film, adhesive, and separate film is placed in a high humidity environment. As a result of the water absorption, the end of the polarizing plate is deformed by the hygroscopic expansion and becomes a wave-like phenomenon.

  It was found that when the polarizer has a thickness of 5 to 15 μm and a biaxially stretched optical film is used, curling of the polarizing plate can be suppressed. Although the mechanism is not clear, when the thickness of the polarizer is 5 to 15 μm, the expansion force is suppressed, and when an optical film stretched biaxially is used, the optical film acts to suppress the expansion of the polarizer. It seems to be.

[Liquid Crystal Display]
The polarizing plate of the present invention can be used for liquid crystal display devices in various display modes. As a display mode of the liquid crystal display device, TN (Twisted Nematic), IPS (In−
Plane Switching, FLC (Ferroelectric Liquid)
Crystal), AFLC (Anti-ferroelectric Liquid)
Liquid crystal display modes such as Crystal), OCB (Optically Compensatory Bend), STN (Super Twisted Nematic), VA (Vertically Aligned), and HAN (Hybrid Aligned Nematic) display modes, etc. It is not limited. Particularly preferably, the liquid crystal display device of the present invention is a VA mode liquid crystal display device.

The liquid crystal display device of the present invention preferably has a low color change during black display after humidity conditioning for 72 hours in an environment of 25 ° C. and a relative humidity of 60%. Specifically, a liquid crystal display device in which Δu′v ′ represented by the following formula 3 is 0 or more and 0.05 or less is preferable.
Formula 3:
In the formula, u′max and v′max are the maximum hues u ′ and v ′ among the values measured in the range of azimuth angle 0 to 360 ° at a polar angle of 60 °, and u′min and v ′. min is the minimum tint u ′ and v ′ among the values measured in the range of azimuth angle 0 to 360 ° when the polar angle is 60 °.

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to the examples. In the following, Examples 10 to 12 are read as Reference Examples 10 to 12, respectively.

<Preparation of cellulose acylate>
(Preparation of cellulose acetate 1)
After 26.8 parts by weight of acetic acid was sprayed on 100 parts by weight of the pulverized pulp and stirred well, it was allowed to stand for 60 hours as a pretreatment. The pretreated pulp was added to a mixture consisting of 323 parts by weight of acetic acid, 245 parts by weight of acetic anhydride and 13.1 parts by weight of sulfuric acid, adjusted to 40 ° C. and acetylated for 90 minutes. A neutralizing agent (24% magnesium acetate aqueous solution) was added so that the amount of sulfuric acid was adjusted to 2.5 parts by weight. Furthermore, after raising the temperature of the reaction bath to 75 ° C., water was added to make the reaction bath moisture (ripening moisture) a concentration of 52 mol%. The aging water concentration was expressed in mol% by multiplying the ratio of the reaction bath water to acetic acid expressed in molar ratio by 100. Thereafter, aging was carried out at 85 ° C. for 100 minutes, and aging was stopped by neutralizing sulfuric acid with magnesium acetate to obtain a reaction mixture containing cellulose diacetate. A dilute acetic acid aqueous solution was added to the obtained reaction mixture to separate cellulose diacetate, followed by washing with water and drying to obtain flakes. Then, the solution was added to a calcium hydroxide aqueous solution having a concentration of 3 × 10 ⁻⁵ g / g at 20 ° C. After soaking for 5 hours, cellulose acetate 1 was obtained by filtering and drying.

(Preparation of cellulose acetate 2)
100 parts by weight of pulverized pulp was pretreated by spraying 50 parts by weight of acetic acid. A mixture consisting of 445 parts by weight of acetic acid, 265 parts by weight of acetic anhydride and 8.3 parts by weight of sulfuric acid was added to the pretreated pulp for acetylation. A neutralizing agent (24% magnesium acetate aqueous solution) was added so that the sulfuric acid amount was adjusted to 4.0 parts by weight, and then aging was performed at a temperature of 85 ° C. The precipitate obtained was dehydrated, washed with pure water, solid-liquid separated, and dried to obtain flakes. Cellulose triacetate 2 was obtained by immersing the above cellulose triacetate flakes in an aqueous calcium hydroxide solution having a concentration of 2 × 10 ⁻⁵ g / g at 20 ° C. for 0.5 hour, followed by filtration and drying.
(Preparation of cellulose acetate 3)
It was prepared in the same manner as the preparation of cellulose acetate 1 except that the aging time was changed from 100 minutes to 200 minutes.
(Preparation of cellulose acetate 4)
The cellulose acetate 2 was prepared in the same manner as the cellulose acetate 2 except that the concentration of the calcium hydroxide aqueous solution for treating flakes was changed to a concentration of 3 × 10 ⁻⁵ g / g.
(Preparation of cellulose acetate 5)
It was prepared in the same manner as in the preparation of cellulose acetate 1 except that the concentration of the aqueous calcium hydroxide solution for treating the flakes was changed to 9 × 10 ⁻⁵ g / g.
(Preparation of cellulose acetate 6)
The cellulose acetate 1 was prepared in the same manner as the cellulose acetate 1 except that the concentration of the calcium hydroxide aqueous solution for treating the flakes was changed to 6 × 10 ⁻⁶ g / g.
(Preparation of cellulose acetate 7)
The cellulose acetate 1 was prepared in the same manner as the cellulose acetate 1 except that the concentration of the calcium hydroxide aqueous solution for treating the flakes was changed to 50 × 10 ⁻⁵ g / g.

<Preparation of dope>
(Preparation of core layer dope solution for Example 1)
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a core layer dope solution.
Cellulose acetate 1 100 parts by mass additive 1 (oligomer 1) 4 parts by weight additive 2 (compound P15) 7.5 parts by weight methylene chloride 394.0 parts by weight methanol 59.0 parts by weight

(Preparation of core layer dope solutions of Examples 2-8 and 10-20 and Comparative Examples 1-5)
The same procedure as in the preparation of the core layer dope solution for Example 1, except that the cellulose acetate described in Table 3 was used and that additive 1 and additive 2 were used in the types and amounts described in Table 3. Thus, a core layer dope solution was prepared. The amount of the solvent was appropriately adjusted so that the cellulose acetate concentration and the solvent composition were the same. The numerical value of the addition amount in Table 3 indicates a part by mass when the amount of cellulose acetate is 100 parts by mass.

(Preparation of skin layer dope solution)
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a skin layer dope solution. Examples 19 and 20 were prepared by adding compound A-3 (described above in the present specification) only to the dope on the support side of the dope for skin layer as described in the table below.
Cellulose acetate 1 or cellulose acetate 2 100 parts by mass Methylene chloride 425.0 parts by mass Methanol 63.0 parts by mass

(Dispersion of matting agent solution)
The following composition was charged into a disperser and stirred to dissolve each component to prepare a matting agent dispersion M1.
2.0 parts by mass of silica particles having an average particle size of 20 nm (AEROSIL (registered trademark) R972, manufactured by Nippon Aerosil Co., Ltd.)
Methylene chloride 76.1 parts by weight Methanol 11.4 parts by weight Skin layer dope solution 12.6 parts by weight

(Preparation of skin layer dope solution with matting agent added)
The skin layer dope solution prepared above was mixed with the matting agent dispersion M1 at the ratio shown below to prepare a skin layer dope solution to which the matting agent was added.
Skin layer dope solution 100.0 parts by mass Matting agent dispersion M1 7.1 parts by mass

<Film formation of cellulose acetate film>
(Casting)
The dope solution prepared above was used in the combinations described in Table 3, and cast by a band casting machine.
When casting the dope solution, as shown in FIG. 1, the dope was cast from the casting die 89 on the traveling band 85 as shown in FIG. Here, by adjusting the casting amount of each dope, the core layer was made the thickest, and as a result, the film thickness of the film after stretching was simultaneously multilayered and co-cast so that the film thickness would be the value shown in the table below. 70 was formed.

  Next, the cast film 70 was peeled off from the cast band 85 to form a wet film, and then dried by a crossover and a tenter to obtain a film. The amount of residual solvent immediately after stripping the dope was about 25% by mass. The film was sent to a drying chamber, and drying was sufficiently promoted while being conveyed while being wound around a number of rollers.

(Fixed end uniaxial stretching)
Films 1 to 16, 19, and 20 were produced by consistently holding a film obtained by casting with a clip and stretching it in the transverse direction under the condition of a uniaxial fixed end. The stretching temperature and the TD stretching ratio were as described in the following table.

(Biaxial stretching)
Optical films 17 and 18 are each stretched by 5% in the longitudinal stretching ratio with a difference in peripheral speed between the metal support speed and the stripping speed (stripping roll draw), and the TD stretching ratio is changed as shown in Table 2. Made. The produced optical films 1 to 20 all have a slow axis parallel to the TD direction.

(Humid heat treatment)
Each film subjected to the stretching treatment was sequentially subjected to a condensation prevention treatment, a wet heat treatment (water vapor contact treatment) and a heat treatment.
In the anti-condensation treatment, the film temperature Tf0 was adjusted to 120 ° C. by applying dry air to each film.
In the wet heat treatment (water vapor contact treatment), the absolute humidity of the wet gas in the wet gas contact chamber (the wet heat treatment absolute humidity) is 250 g / m ^3, and the dew point of the wet gas is higher than the temperature Tf0 of each film. Each film was conveyed while maintaining the temperature (wet heat treatment temperature) of each film at 100 ° C. for only the treatment time (60 seconds).

In the heat treatment, the absolute humidity of the gas in the heat treatment chamber (heat treatment absolute humidity) is set to 0 g / m ³ , the temperature of each film (heat treatment temperature) is set to the same temperature as the wet heat treatment temperature, and the treatment time (2 minutes) is maintained. did. The film surface temperature was determined from the average value obtained by attaching a tape-type thermocouple surface temperature sensor (ST series manufactured by Anri Keiki Co., Ltd.) to the film at three points.

(Take-up)
Then, after cooling to room temperature, the film was wound up.

<Evaluation>
The following evaluation was performed about the film of Examples 1-8 and 10-20, and Comparative Examples 1-5.

(Measurement of film thickness)
Anritsu Co., Ltd. Electronic Micrometer K, sampling 5 points evenly in the width direction
Measured by 402B.
(Measurement of film thickness of skin layer)
Five points were sampled evenly in the width direction, and the cross-section was appropriately flattened with a microtome, and measured by observation with an optical microscope.

(All layers average acyl substitution degree)
Based on the acyl substitution degree and the amount used of each cellulose acetate used in the skin layer and the core layer, the average acyl substitution degree in the entire film layer was determined.

(Quantification of calcium in the entire film)
0.06 g of each sample was weighed, 8 ml of 70% nitric acid (electronic industrial grade, manufactured by Kanto Chemical Co., Inc.) was added, sealed in a pressure-resistant container, heated in a microwave at 210 ° C. for 70 minutes, and incinerated. . Take out the sample, measure the solution up to 80 g with pure water by high frequency inductively coupled plasma optical emission spectrometry (ICP-OES) method (PerkinElmer Optima7300DV, organic solvent mode (oxygen 40 ml / min, axial photometry)), absolutely It was determined by analyzing with a calibration curve method.

(Quantification of calcium on the film surface)
A thickness of 2 μm from each surface of each film was scraped with a cutter blade, and the content of calcium contained in the powder was determined for the collected powder by the same method as the above-described calcium determination.

(Quantitative determination of calcium in the center of the film)
Using the sample obtained by removing the thickness of 2 μm from each surface of each film, the content of calcium contained in the powder was determined in the same manner as the above-described calcium determination.

(Initial film color evaluation)
Each film was wound up by 2000 m or more, and sensory evaluation was performed on the yellow color at the end. If it is 1-2, it is a level which is satisfactory practically.
1: Yellowish color is not felt.
2: Feels a little yellowish.
3: Strongly yellowish.

(Band peelability)
Each film was evaluated for band peelability based on the following evaluation method. If it is 1 to 3, it can be used at a level where there is no practical problem.
1: The peelability was very good, and optical unevenness was hardly visible on the film after peeling.
2: The peelability was good, and optical unevenness was slightly visible on the film after peeling.
3: Separation was possible, and the film had no stepped film thickness unevenness after peeling, but optical unevenness was visible.
4: The peelability was poor, and stepwise film thickness unevenness was visible on the film after peeling.
5: The peelability was very poor, and the film was partially stretched at the time of peeling in addition to the stepped film thickness unevenness.

  The results of the above evaluation are shown in Tables 5 and 6.

<Preparation of protective film>
(Preparation of cellulose ester solution for first skin layer and second skin layer)
The following composition was put into a mixing tank, stirred while heating to dissolve each component, and a cellulose ester solution for the first skin layer and the second skin layer was prepared.

Composition of cellulose ester solution for first skin layer and second skin layer:
Cellulose ester (acetyl substitution degree 2.86) 100 parts by weight Sugar ester compound of formula (I) 3 parts by weight Sugar ester compound of formula (II) 1 part by weight UV absorber 2.4 parts by weight silica particle dispersion (average particle size) 16 nm) 0.078 parts by mass (AEROSIL (registered trademark) R972, Nippon Aerosil Co., Ltd. methylene chloride 339 parts by mass Methanol 74 parts by mass Butanol 3 parts by mass

(Preparation of cellulose ester solution for core layer)
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose ester solution for the core layer.

Composition of cellulose ester solution for core layer Cellulose ester (acetyl substitution degree 2.86) 100 parts by mass Sugar ester compound of formula (I) 7.7 parts by mass Sugar ester compound of formula (II) 2.3 parts by mass UV absorber 2.4 parts by mass Methylene chloride 266 parts by mass Methanol 58 parts by mass Butanol 2.6 parts by mass

(Filming by co-casting)
As a casting die, an apparatus equipped with a feed block adjusted for co-casting so that a film having a three-layer structure can be formed was used. The cellulose ester solution for the first skin layer, the cellulose ester solution for the core layer, and the cellulose ester solution for the second skin layer were co-cast on a drum cooled to −7 ° C. from the casting port. At this time, the flow rate of each dope was adjusted so that the ratio of the thickness was first skin layer / core layer / second skin layer = 5/53/2.
It casted on the mirror surface stainless steel support body which is a drum of diameter 3m. A dry air of 34 ° C. was applied on the drum at 270 m ³ / min.
The cellulose ester film cast and rotated 50 cm before the end point of the casting part was peeled off from the drum, and then both ends were clipped with a pin tenter. At the time of peeling, 5% stretching was performed in the MD direction.

The cellulose ester web held by the pin tenter was conveyed to the drying zone. In the initial drying, a drying air of 45 ° C. was blown and then dried at 110 ° C. for 5 minutes. At this time, the cellulose ester web was conveyed in the TD direction while stretching at a stretching rate of 10%.
After releasing the web from the pin tenter, the portion held by the pin tenter was continuously cut out and dried at 145 ° C. for 10 minutes while applying a 210 N tension in the MD direction. Furthermore, the width direction edge part was continuously cut off so that a web might become desired width, and the unevenness | corrugation of the width of 15 mm and a height of 10 micrometers was attached to the both ends of the width direction of a web, and a film with a film thickness of 60 micrometers was produced. A protective film 2A was obtained.

<Preparation of polarizing plate>
The surfaces of the optical films of Examples 1 to 8 and 10 to 20 and Comparative Examples 1 to 5 were subjected to alkali saponification treatment. It was immersed in a 1.5 mol / L aqueous sodium hydroxide solution at 45 ° C. for 2 minutes, washed in a water bath at room temperature, and neutralized with 0.05 mol / L sulfuric acid at 30 ° C. Again, it was washed in a water bath at room temperature and further dried with hot air at 100 ° C. Subsequently, a roll-shaped polyvinyl alcohol film having a thickness of 60 μm was continuously stretched 5 times in an iodine aqueous solution and dried to obtain a polarizer having a thickness of 15 μm. Using the 3% by weight aqueous solution of polyvinyl alcohol (Kuraray PVA-117H) as an adhesive, the above-described alkali saponified optical films of Examples and Comparative Examples, and the protective film 2A similarly alkali saponified were prepared. Then, a laminated laminate was obtained so as to be between the optical film of Example or Comparative Example and the protective film 2A. At this time, the MD direction of the optical film of Example or Comparative Example and the protective film 2A was made parallel to the absorption axis direction of the polarizer.

  An acrylic pressure-sensitive adhesive layer having a thickness of 15 μm was provided on the surface on the optical film side in Examples or Comparative Examples, and a separate film having a thickness of 38 μm was further bonded to the outside thereof. In the above polarizing plate, a protective film having a thickness of 60 μm composed of an acrylic pressure-sensitive adhesive layer and a polyethylene terephthalate film was bonded to the surface on the protective film 2A side to produce a polarizing plate.

<Evaluation of polarizing plate>
(Change in optical properties after storage at high temperature and low humidity)
Two samples (5 cm × 5 cm) in which the polarizing plates of each of the examples and comparative examples prepared above were each attached to glass via an adhesive were prepared. Under the present circumstances, it affixed so that the film of the produced said Example and a comparative example might become the glass side. After conditioning for 24 hours in an environment of 25 ° C. and a relative humidity of 60%, this sample was set with the glass side facing the light source, and the Rth (wavelength 550 nm) of the films of the above-mentioned Examples and Comparative Examples was measured separately. . Each of the two samples was measured to obtain an initial value of Rth (550).
Thereafter, the film was stored for 1000 hours in a dry environment at 80 ° C., and further adjusted for humidity for 24 hours in an environment at 25 ° C. and a relative humidity of 60%. ) Separated measurement. Axoscan (manufactured by Axometrics) was used for optical property separation measurement. In addition, a blast constant temperature thermostat DN64 manufactured by Yamato Scientific Co., Ltd. was used for aging in an 80 ° C. dry environment. Α was calculated along the following formula with the two polarizing plates, and the average value was taken as the value of the film of the example and the comparative example. Evaluation was made according to the following criteria. The results are shown in Table 6. If it is 1-2, there is no problem in practical use.
α = [Rth after aging (550) −initial Rth (550)] / initial Rth (550)
1: α is 0.10 or less 2: α is greater than 0.10 and 0.20 or less 3: α is greater than 0.20

(Change in polarization performance after storage at high temperature and high humidity)
For the polarizing plates of Examples and Comparative Examples prepared above, the orthogonal transmittance Tc (730) of the polarizer at a wavelength of 730 nm was measured by the following method.
The orthogonal transmittance Tc (730) of the polarizing plate was measured at a wavelength of 730 nm by the following method using an automatic polarizing film measuring device VAP-7070 manufactured by JASCO Corporation.
In general, the orthogonal transmittance is
(A) a measuring method using two polarizing plates and measuring the absorption axis of the polarizer orthogonally;
(B) Using two types of measurement methods: a measurement method in which a single polarizing plate is used, and the absorption axis of the Grand Taylor prism attached to the apparatus and the polarizer absorption axis of one polarizing plate are arranged orthogonally. Can be measured. Here, the measurement method of (B) was employ | adopted among the measurement methods of said (A) and (B).
Two samples (5 cm × 5 cm) in which a polarizing plate was attached on glass via an adhesive were prepared. Under the present circumstances, it affixed so that the film of the produced said Example and a comparative example might become the glass side. After adjusting the humidity for 24 hours in an environment of 25 ° C. and a relative humidity of 60%, this sample was set with the glass side facing the light source, and the orthogonal transmittance was measured. Two samples were measured respectively, and the average value was defined as the orthogonal transmittance.
Thereafter, the film was stored for 72 hours in an environment of 85 ° C. and a relative humidity of 85%, and then, after the humidity was adjusted for 24 hours in an environment of 25 ° C. and a relative humidity of 60%, the orthogonal transmittance was measured by the same method. The amount of change ΔTc (730) in the orthogonal transmittance before and after aging was determined and evaluated according to the following criteria. The result is shown in Table 6 below as the polarizer durability. If it is 0-3, it is a level which is satisfactory practically.
0: Change in orthogonal transmittance at wavelength 730 nm is less than 0.15% 1: Change in orthogonal transmittance at wavelength 730 nm is less than 0.3% 2: Change in orthogonal transmittance at wavelength 730 nm is 0.3% or more and less than 0.5% 3: Orthogonal transmittance change at a wavelength of 730 nm is 0.5% or more and less than 1.0% 4: Orthogonal transmittance change at a wavelength of 730 nm is 1.0% or more

<Production of liquid crystal display device>
Each of the polarizing plates in the VA liquid crystal cell was prepared so that the pressure-sensitive adhesive side (that is, the optical film side in the example or comparative example) was on the liquid crystal cell side by using two polarizing plates in the above examples and comparative examples. The liquid crystal display devices of Examples and Comparative Examples were fabricated by pasting them so that the absorption axes of the liquid crystal were orthogonal to each other. The VA liquid crystal cell was used by peeling off the front and back polarizing plates and retardation plate of a commercially available VA mode liquid crystal display device (LC-40 H9, manufactured by Sharp Corporation).

<Evaluation of liquid crystal display device>
(Color change when viewed from an oblique direction)
About each produced liquid crystal display device, the brightness | luminance and color at the time of black display are measured using EZ-Contrast XL88 (made by ELDIM) after humidity control for 72 hours in the environment of 25 degreeC and 60% of relative humidity. Then, the luminance value and chromaticity value (u′v ′) of each point are measured by 5 ° for each of the polar angle 0 to 80 ° and the azimuth angle 0 to 360 °, and the color change Δu′v ′ is expressed by the following formula Was measured based on each.
Here, u′max (v′max) is the maximum of u ′ (v ′) and u′min (v′min) among the values measured in the range of azimuth angle 0 to 360 ° when the polar angle is 60 °. Is the smallest u ′ (v ′) among the values measured in the range of azimuth angle 0 to 360 ° at a polar angle of 60 °. The results are shown in Table 6 below.
Here, with respect to the surface of the display device, an arbitrary direction in the plane was set to an azimuth angle of 0 °, and a vertical direction to the plane was set to a polar angle of 0 °.

1: 0.02 or less 2: Exceeding 0.02: 0.05 or less 3: Exceeding 0.05: 0.08 or less 4: Exceeding 0.08

[Change in color after storage at high temperature and low humidity]
About each produced liquid crystal display device, after preserve | saving for 1000 hours in an 80 degreeC dry environment, the color observed from the front was visually evaluated after humidity control for 24 hours in an environment of 25 degreeC and a relative humidity of 60%. The results are shown in Table 6. 1-2 is not a problem in practice.
1: Redness is not felt.
2: A faint redness is felt.
3: Redness is felt.

(Summary of Examples)
The films of Examples 1 to 8 and 10 to 20 containing the compound represented by the general formula 1 and having a calcium amount of 5 × 10 ⁻⁵ g / g or more and less than 5 × 10 ⁻⁴ g / g of the entire film are evaluated. All the items were good and practically satisfactory. Furthermore, it was found that the change in performance at high temperature and high humidity storage was much better in the polarizing plate containing compound A-3 in the skin layer. On the other hand, in Comparative Example 1 not including the compound represented by the general formula 1, the change in optical properties after storage of the polarizing plate at high temperature and low humidity was poor. Further, in Comparative Example 4 in which the calcium amount of the entire film is less than 5 × 10 ⁻⁵ g / g, the color change after storage at high temperature and low humidity of the liquid crystal display device is poor, and the calcium amount of the entire film layer is 5 In Comparative Example 5 which is × 10 ⁻⁴ g / g or more, the initial film color evaluation was poor.

(Preparation of polarizing plate with antiglare layer)
The antiglare layer was produced using the method described in JP2013-228720A, and a protective film 3A in which the antiglare layer was arranged as follows was produced.

[Synthesis of synthetic smectite]
Put 4L of water in a 10L beaker, dissolve 860g of No. 3 water glass (SiO ₂ 28%, Na ₂ O 9%, molar ratio 3.22), and add 162g of 95 mass% sulfuric acid all at once with stirring. A salt solution was obtained. Next, 560 g of MgCl ₂ .6H ₂ O primary reagent (purity 98%) was dissolved in 1 L of water, and this was added to the above silicate solution to prepare a homogeneous mixed solution. This was dropped into 3.6 L of 2 mol / L NaOH aqueous solution over 5 minutes with stirring.
The reaction precipitate consisting of the obtained silicon-magnesium composite (a homogeneous composite in which colloidal particles are aggregated) is immediately filtered by a cross flow system (cross flow filter (ceramic) manufactured by NGK. Membrane filter: pore size 2 μm, tubular type, filtration area 400 cm ² )] and sufficiently washed with water, and then a slurry of 200 ml of water and 14.5 g of Li (OH) · H ₂ O was added to form a slurry. . This was transferred to an autoclave and subjected to a hydrothermal reaction at 41 kg / cm ² and 250 ° C. for 3 hours. After cooling, the reaction product was taken out, dried at 80 ° C., and pulverized to obtain a synthetic smectite having a composition of hectorite, which is one type of smectite, represented by the following formula.
Na _0.4 Mg _2.6 Li _0.4 Si ₄ O ₁₀ (OH) ₂

[Synthesis of smectite-type clay organic composite 1]
20 g of the synthetic smectite obtained above was dispersed in 1000 ml of tap water. To this dispersion was added 300 ml of a solution in which 11.1 g (2.2 mmol as trioctyl methyl ammonium chloride) containing 80% by mass of quaternary ammonium salt trioctyl methyl ammonium chloride was dissolved in pure water. The mixture was reacted at room temperature (25 ° C.) for 2 hours with stirring. Next, the product was separated into solid and liquid, washed to remove byproduct salts, dried and pulverized to obtain a smectite clay organic composite 1.

(Preparation of coating solution for antiglare layer)
Composition of coating solution for antiglare layer:
Smectite clay organic composite 1 1.20 parts by mass Resin particles 8.00 parts by mass PET-30 90.65 parts by mass Irg907 3.00 parts by mass SP-13 0.15 parts by mass Azisper P881 0.30 parts by mass

  The above components were mixed with a mixed solvent of MIBK (methyl isobutyl ketone): MEK (methyl ethyl ketone) [= 85: 15]. An antiglare layer coating solution was prepared by filtering through a polypropylene filter having a pore size of 30 μm. The solid concentration of the coating solution is 35% by mass. In preparing the coating solution, the resin particles and the smectite clay organic composite were added in the form of a dispersion.

(Preparation of resin particle dispersion)
The resin particle dispersion was prepared by gradually adding the resin particles to the stirred MIBK solution until the solid content concentration of the dispersion reached 30% by mass and stirring for 30 minutes.
The resin particles are translucent, and a crosslinked styrene-methyl methacrylate copolymer prepared by appropriately changing the copolymerization ratio of styrene and methyl methacrylate so that the average particle diameter is 2.5 μm and the refractive index is 1.52. Combined particles were used (manufactured by Sekisui Plastics Co., Ltd.).

(Preparation of dispersion of smectite clay organic composite 1)
The dispersion of the smectite clay organic composite 1 is gradually added to all MEKs used in the antiglare layer coating solution, and the smectite clay organic composite 1 is gradually added and stirred for 30 minutes. Prepared.

The compounds used are shown below.
PET-30: A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate [manufactured by Nippon Kayaku Co., Ltd.]
Irgacure 907: Acetophenone photopolymerization initiator [manufactured by BASF] (referred to as “Irg907” in the table below)
SP-13: The following fluorosurfactant (60:40 (molar ratio))
Mw represents molecular weight.
Addispar PB881: Ajinomoto Fine Chemical Co., Ltd. Polymer pigment dispersant

(Coating of antiglare layer)
An anti-glare layer was applied to the surface that was on the air interface side when the protective film 2A was formed so as to have a film thickness of 5.5 μm to produce a protective film 3A.
Specifically, each coating solution was applied under the condition of a conveyance speed of 30 m / min by a die coating method using a slot die described in Example 1 of JP-A-2006-122889, and dried at 80 ° C. for 150 seconds. Further, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of about 0.1% under a nitrogen purge, ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 180 mJ / cm ² were irradiated. After the coating layer was cured to form an antiglare layer, it was wound up to produce a protective film 3A provided with the antiglare layer.

<Preparation of polarizing plate having antiglare layer>
The protective film 3A having an antiglare layer and Examples 1, 2, and 20 were subjected to alkali saponification treatment. It was immersed in a 1.5 mol / L aqueous sodium hydroxide solution at 45 ° C. for 2 minutes, washed in a water bath at room temperature, and neutralized with 0.05 mol / L sulfuric acid at 30 ° C. Again, it was washed in a water bath at room temperature and further dried with hot air at 100 ° C. Subsequently, a roll-shaped polyvinyl alcohol film having a thickness of 60 μm was continuously stretched 5 times in an iodine aqueous solution and dried to obtain a polarizer having a thickness of 15 μm. Using a 3% by weight aqueous solution of polyvinyl alcohol (Kuraray PVA-117H) as an adhesive, the surface on which the antiglare layer of the protective film 3A subjected to the alkali saponification treatment was not applied was bonded to a polarizer. Polarizing plates 101 to 105 having antiglare layers were obtained by pasting Examples 1, 2, and 20 similarly subjected to alkali saponification treatment on the other surface of the polarizer. At this time, the surface of the film of the example to be bonded to the polarizer was as shown in the table below. Further, the MD direction of the optical film of Example and the protective film 3A was made parallel to the absorption axis direction of the polarizer.

(Haze change after storage at high temperature and high humidity)
About each polarizing plate affixed on glass through the adhesive produced above, 85 degreeC and relative humidity 85 are set with the haze measured after humidity control for 24 hours in an environment of 25 degreeC and a relative humidity of 60% as an initial value. The haze value after conditioning for 24 hours in an environment of 25 ° C. and a relative humidity of 60% was taken as the haze value after aging. The initial haze value was subtracted from the haze value after the lapse of time, and the haze change after storage at high temperature and high humidity was evaluated. The haze of the polarizing plate with glass represents the haze value (%) measured according to JIS K7136 with the glass side of the sample facing the light source, and a turbidimeter (NDH2000, Nippon Denshoku Industries Co., Ltd.). )).

  The polarizing plate (polarizing plate 104, 105) bonded on the support surface has a small increase in haze relative to the polarizing plate (polarizing plate 101, 102) bonded on the air interface side, and is a skin layer close to the adhesive layer. The polarizing plate 103 using the film of Example 20 to which only Compound A-3 was added was also the result of a small increase in haze.

(Production of long polarizing plate)
A rolled polyvinyl alcohol film was continuously stretched 5 times in an aqueous iodine solution and dried to obtain a polarizer. Optical of Example 1 subjected to alkali saponification treatment (soaked in a 2 mol% sodium hydroxide solution at 50 ° C. for 90 seconds, then washed with water and dried) using a 3% by weight aqueous solution of polyvinyl alcohol (Kuraray PVA-117H) as an adhesive A film and a protective film 2A are prepared, and the saponified surface is placed on the polarizer side so that the polarizer is sandwiched between them, and the optical film, the polarizer, and the protective film 2A of Example 1 are attached in this order. Each combined polarizing plate was obtained. At this time, the optical film and the protective film of the present invention are attached so that the MD direction (film transport direction) of the protective film is parallel to the absorption axis of the polarizer, and the acrylic film having a thickness of 15 μm is attached to the surface of the retardation film of the polarizing plate. A system pressure-sensitive adhesive layer was provided, and a separate film having a thickness of 38 μm was bonded to the outside thereof. In the above polarizing plate, a protective film having a thickness of 60 μm composed of an acrylic pressure-sensitive adhesive layer and a polyethylene terephthalate film was bonded to the surface on the outer film side to prepare a polarizing plate 201 for evaluation. Polarizers 202 to 208 were produced in the same manner as the polarizer 201 except that the thickness of the polarizer and the optical film were changed as shown in the table below.

(Evaluation method of wave curl)
The polarizing plate produced above was punched into a rectangle having a long side direction of 1150 mm and a short side direction of 645 mm. At this time, the absorption axis of the polarizing plate was made parallel to the short side. The punched polarizing plate was allowed to stand on a flat surface for 24 hours in a 23 ° C. and 55% relative humidity environment with the separate film on the bottom. The maximum value of the floating amount from the flat surface for each wave was taken as the height of the wave, and the measurement was performed using straight silver (manufactured by Shinwa Measurement Co., Ltd.). The measurement of the height of each wave on each side of the polarizing plate was carried out in a state in which the separate film was placed on the bottom and a state in which the separate film was placed on the top.

  A portion where the height of the wave is 1 mm or more was measured as one wave, and the number of waves on each side of the polarizing plate and the height of the wave were measured. The measurement results are shown in the following table. Among the number of waves on each side, the maximum value is called “wave number”, and the maximum wave height of all measurement results is called “wave height”. If the wave height is 3 mm or less and the wave number is 3 or less, there is no practical problem.

  The polarizing plates using the biaxially stretched optical films (Examples 17 and 18) were better in wave height and wave number than the uniaxially stretched optical films (Examples 1 and 2). Further, the polarizing plate having a polarizer thickness of 10 μm was better in both wave height and wave number than the polarizing plate having a thickness of 25 μm.

70 Casting film 85 Casting band 89 Casting die 120 Core layer dope 121 First skin layer dope 122 Second skin layer dope 120a Core layer 121a First skin layer 122a Second skin layer 150 First Second skin layer (support layer) die 151 Core layer (base layer) die 152 First skin layer (air surface layer) die

Claims (14)

The cellulose acylate having an average acyl substitution degree of 2.0 to 2.6 is included, and the calcium content in the whole film is 5 × 10 ⁻⁵ g / g or more and less than 5 × 10 ⁻⁴ g / g. An optical film comprising the compound represented by 1:
In general formula 1, X represents —CH—; Y represents —N—;
Q ₁ and Q ₂ each represent —CO—;
Q ₃ represents a single bond or a divalent linking group ;
R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a halogen group or a heterocyclic group. The cellulose acylate film having an average acyl substitution degree of 2.6 to 3.0 is laminated on at least one surface of the cellulose acylate film having an average acyl substitution degree of 2.0 to 2.55. 1. The optical film as described in 1. The optical film of Claim 1 or 2 which contains 2.3-7.5 mass parts of compounds shown by General formula 1 with respect to 100 mass parts of cellulose acylates. The optical film according to any one of claims 1 to 3, comprising 1 to 9 parts by mass of a polycondensation ester of a dicarboxylic acid and an aliphatic diol with respect to 100 parts by mass of cellulose acylate. The optical film of Claim 4 whose 50 mol% or more is a terephthalic-acid component among the dicarboxylic acid components in the said polycondensation ester. The optical film according to any one of claims 1 to 5, wherein the film thickness is 5 µm or more and 50 µm or less. From one surface of the film to a calcium content in a region having a depth of 2 μm and from the other surface of the film to a calcium content in a region having a depth of 2 μm, the depth of 2 μm or more from the one surface of the film to the other surface of the film The optical film according to claim 6, wherein the calcium content in the region from 1 to 2 μm in depth is higher. The optical film according to any one of claims 1 to 7, wherein α defined by the following formula 2 is 0 or more and 0.20 or less:
Formula 2: α = [Rth (550) after time-initial Rth (550)] / initial Rth (550)
Here, the initial Rth (550) is Rth measured at a wavelength of 550 nm after conditioning for 24 hours in a 25 ° C. and 60% relative humidity environment, and the Rth (550) after aging. Rth measured at a wavelength of 550 nm after measurement of the initial Rth (550) value, storage for 1000 hours in a dry environment at 80 ° C., and then conditioning for 24 hours in an environment of 25 ° C. and a relative humidity of 60%. It is. Rth indicates retardation in the thickness direction. The manufacturing method of the optical film of any one of Claim 1 to 8 including the film forming process which casts the dope containing a cellulose acylate, calcium, and the compound shown by following General formula 1 on a support body.
In general formula 1,
X represents —CH—; Y represents —N—;
Q ₁ and Q ₂ each represent —CO—;
Q ₃ represents a single bond or a divalent linking group ;
R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a halogen group or a heterocyclic group. A core layer forming dope containing cellulose acylate, calcium and a compound represented by the general formula 1 according to claim 9, and a skin layer forming dope containing cellulose acylate on the support. The manufacturing method of the optical film of Claim 9 which is the process of co-casting. The method for producing an optical film according to claim 10, wherein a calcium content with respect to a cellulose acylate mass in the core layer forming dope is larger than a calcium content with respect to a cellulose acylate mass in the skin layer forming dope. A polarizing plate having a polarizer and the optical film according to claim 1. A liquid crystal display device comprising the polarizing plate according to claim 12. The Δu′v ′ represented by the following formula 3 which is a color change at the time of black display after conditioning for 72 hours in an environment of 25 ° C. and a relative humidity of 60% is 0 or more and 0.05 or less. LCD device:
Formula 3:
In the formula, u′max and v′max are the maximum hues u ′ and v ′ among the values measured in the range of azimuth angle 0 to 360 ° at a polar angle of 60 °, and u′min and v ′. min is the minimum tint u ′ and v ′ among the values measured in the range of azimuth angle 0 to 360 ° when the polar angle is 60 °.