JP2008107501A - Polarizing plate and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate with retardation film which has high productivity, hardly causes curling due to a change in temperature and humidity and is excellent in moisture proof property, and to provide a liquid crystal display device which hardly causes light leakage due to the change in temperature and humidity. <P>SOLUTION: The polarizing plate includes: a polarizing film; a protective film (A) which is stacked on one side surface of the polarizing film and uses a polymer film (a) as a base; and a protective film (B) which is stacked on the other side surface of the polarizing film and uses a polymer film (b) as a base, wherein water vapor permeability at 60°C, 95%RH of the protective film (A) is ≤200 g/(m<SP>2</SP>day) and the difference between hygroscopic swelling coefficient of the protective film (A) and hygroscopic swelling coefficient of the protective film (B) is ≤10 ppm/%RH. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polarizing plate and a liquid crystal display device, and in particular, has high productivity, hardly curls against temperature and humidity changes, has high moisture resistance, and has a polarizing plate with a retardation film, and the polarizing plate. The present invention relates to a liquid crystal display device with excellent viewing angle characteristics.

Liquid crystal display devices are widely used in monitors for personal computers and portable devices, and for television applications because of their various advantages, such as low voltage and low power consumption, enabling miniaturization and thinning. Various modes have been proposed for such a liquid crystal display device depending on the alignment state of the liquid crystal molecules in the liquid crystal cell. Conventionally, the liquid crystal display device is in an alignment state twisted by about 90 ° from the lower substrate to the upper substrate of the liquid crystal cell. The TN mode was mainstream.
In general, a liquid crystal display device is composed of a liquid crystal cell, a retardation film, and a polarizer (polarizing film), and the optically anisotropic layer is laminated by applying a liquid crystal to a stretched birefringent film or a transparent film. A phase difference film is used.
For example, Patent Document 1 discloses a technique for expanding a viewing angle by applying an optical compensation sheet in which a discotic liquid crystal is applied on a cellulose acylate film, aligned, and fixed thereto to a TN mode liquid crystal cell.
However, a television-use liquid crystal display device that is expected to be viewed from various angles on a large screen has a strict requirement for viewing angle dependency, and the above-described method cannot satisfy the requirement.
Therefore, liquid crystal display devices different from the TN mode, such as an IPS (In-Plane Switching) mode, an OCB (Optically Compensatory Bend) mode, and a VA (Vertically Aligned) mode, have been studied. In particular, the VA mode is attracting attention as a liquid crystal display device for TV because of its high contrast and relatively high manufacturing yield.

Here, the cellulose acylate film is characterized by high optical isotropy (low retardation value) as compared with other polymer films.
Therefore, a cellulose acylate film is generally used for applications requiring optical isotropy, for example, a protective film for a polarizing plate (also referred to as a protective film), and the cellulose acylate film is used as a polarizing plate. A polarizing plate used as a protective film on both sides is widely used.
On the other hand, an optical anisotropy (high retardation value) is required for the optical compensation film (retardation film) of the liquid crystal display device. For example, an optical compensation film for VA requires a front retardation (Re) of 30 to 200 nm and a retardation (Rth) in the thickness direction of 70 to 400 nm.
Therefore, it is common to use a synthetic polymer film having a high retardation value such as a polycarbonate or polysulfone film as the optical compensation film.
As described above, in the optical material technical field, when a polymer film requires optical anisotropy (high retardation value), a synthetic polymer film is used, and optical isotropy (low retardation value) is obtained. When required, it was common to use cellulose acylate films.

However, when a synthetic polymer film such as a polycarbonate film is used as a retardation film, a step of further laminating the retardation film is required after producing a polarizing plate having a cellulose acylate film as a protective film on both sides. For this reason, there are problems that the manufacturing process becomes complicated, the productivity is low, and the manufacturing cost is high.
On the other hand, in recent years, a technology capable of directly bonding a retardation film using a synthetic polymer film to a polarizing film without using a protective film of a cellulose acylate film has been developed, and this productivity problem has been solved. It's getting on. (For example, see Patent Document 2)

In recent years, when a cellulose acylate film is used as a protective film on one side of a polarizing plate and a synthetic polymer film is used on the other side, the problem of curling has been reduced due to the difference in expansion coefficient due to wet heat changes between the two films. This has been clarified by the inventors' research.
Specifically, in the process of producing a polarizing plate, the method of continuously laminating a long roll on a continuously formed polarizing film has the highest productivity. In particular, when a polarizing plate is produced in a roll shape, it becomes a cause of breakage and wrinkles in the drying and transporting processes, and the productivity is remarkably reduced.

On the other hand, the cellulose acylate film has high moisture permeability, and when such a film is used as a protective film and is placed outside when bonded to a liquid crystal display device, the influence of humidity change is directly transmitted to the polarizing film.
Therefore, it has been found that when a liquid crystal display device equipped with this polarizing plate is used for a long period of time, a problem of non-uniform light leakage due to expansion and contraction of the polarizing film due to humidity change of the outside air has occurred.

Japanese Patent No. 2587398 JP 2005-181817 A

The present invention aims to solve the above-described problems and achieve the following objects. That is, it is an object of the present invention to provide a polarizing plate with high productivity, low curling with respect to temperature and humidity changes, and high moisture resistance.
It is another object of the present invention to provide a liquid crystal display device with little light leakage against temperature and humidity changes.

Means for solving the above-mentioned problems are as follows. That is,
<1> A polarizing film, a protective film (A) that is laminated on one surface of the polarizing film, and a polymer film (a) as a base material, and a laminated film on the other surface of the polarizing film, ) And a protective film (B) based on
The moisture permeability at 60 ° C. and 95% RH of the protective film (A) is 200 g / m ² · day or less,
The polarizing plate is characterized in that the difference between the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) is 10 ppm /% RH or less.
<2> The polarizing plate according to <1>, wherein the difference between the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) is 5 ppm /% RH or less.
<3> The polarizing plate according to any one of <1> to <2>, wherein the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) are both 50 ppm /% RH or less. is there.
<4> The polarizing plate according to any one of <1> to <3>, wherein the polarizing plate has a long roll shape.
<5> The polarizing plate according to any one of <1> to <4>, wherein the in-plane retardation Re of the polymer film (b) is 15 to 300 nm and / or the retardation Rth in the thickness direction is 60 to 300 nm. It is.
<6> The polymer film (b) has an in-plane retardation Re of 15 to 300 nm, and the slow axis of the polymer film (b) and the absorption axis of the polarizing plate are substantially perpendicular to each other <1. > To <5>.
<7> The functional layer is formed on the polymer film (b), the in-plane retardation Re of the functional layer is 15 to 300 nm, and / or the thickness direction retardation Rth is 60 to 300 nm <1 > To <6>.
<8> The polarizing plate according to <7>, wherein the functional layer is an optically anisotropic layer formed from a liquid crystalline compound.
<9> The polarizing plate according to any one of <1> to <8>, wherein a hard coat layer is formed on the polymer film (a).
<10> The polarizing plate according to any one of <1> to <9>, wherein at least one of the polymer film (a) and the polymer film (b) is a polycarbonate film.
<11> The polarizing plate according to any one of <1> to <9>, wherein at least one of the polymer film (a) and the polymer film (b) is a norbornene-based film.

<12> The polarizing plate according to any one of <1> to <11> and a liquid crystal cell, wherein the protective film (B) side of the polarizing plate is bonded to the liquid crystal cell. This is a liquid crystal display device.
<13> A liquid crystal molecule comprising a pair of polarizing plates whose absorption axes are orthogonal to each other, a pair of substrates disposed between the polarizing plates, and a liquid crystal layer sandwiched between the substrates, and the liquid crystalline molecules The liquid crystal display device according to <12>, wherein the liquid crystal display device is aligned in a direction substantially perpendicular to the substrate in a non-driving state where no external electric field is applied.
<14> A liquid crystal molecule comprising a pair of polarizing plates whose absorption axes are orthogonal to each other, a pair of substrates disposed between the polarizing plates, and a liquid crystal layer sandwiched between the substrates. The liquid crystal display device according to <12>, wherein the liquid crystal display device is aligned in a substantially horizontal direction with respect to the substrate in a non-driving state where no external electric field is applied.

According to the present invention, it is possible to provide a polarizing plate that is less likely to curl with respect to temperature and humidity changes and has high moisture resistance.
Further, according to the present invention, it is possible to provide a liquid crystal display device with less light leakage with respect to temperature and humidity changes.

  Hereinafter, an embodiment of the liquid crystal display device of the present invention and its constituent members will be described in order. 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, “parallel” and “orthogonal” mean that the angle is within a range of strictly less than ± 10 °. In this range, an error from a strict angle is preferably less than ± 5 °, and more preferably less than ± 2 °. “Substantially parallel”, “substantially orthogonal”, and “substantially vertical” have the same meaning. Further, the “slow axis” means a direction in which the refractive index is maximized. Further, the measurement wavelength of the refractive index and the phase difference is a value at λ = 590 nm in the visible light region unless otherwise specified.

In this specification, “polarizing plate” is cut into a size to be incorporated into a long polarizing plate and a liquid crystal device unless otherwise specified (in this specification, “cutting” includes “punching” and “cutting out”. It is used in the meaning including both of the polarizing plates. In this specification, “polarizing film” and “polarizing plate” are distinguished from each other. “Polarizing plate” means a laminate having a transparent protective film for protecting the polarizing film on at least one side of the “polarizing film”. It shall be.
In the present specification, the description “(meth) acrylate” means “at least one of acrylate and methacrylate”. The same applies to “(meth) acrylic acid” and the like.

In the present specification, Re (λ) and Rth (λ) respectively represent in-plane retardation and retardation in the thickness direction at the wavelength λ. The measurement wavelength λ nm may be any wavelength as long as it is in the visible light range, specifically, in the range of 400 to 800 nm, but is preferably in the range of 400 to 750 nm, preferably in the range of 400 to 700 nm. It is more preferable that
In this specification, unless otherwise specified, Re and Rth mean values measured at 530 to 600 nm (or values calculated based on these values).
The in-plane retardation (Re) is a value measured by making light of wavelength λ nm incident in the film normal direction in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments). When the film to be measured is represented by a uniaxial or biaxial refractive index ellipsoid, Rth is calculated by the following method.

Rth is the Re, with the in-plane slow axis (determined by KOBRA 21ADH or WR) as the tilt axis (rotary axis) (in the absence of the slow axis, any direction in the film plane is the rotational axis) )) At a step of 10 degrees from the normal direction to 50 degrees on one side with respect to the film normal direction, light of wavelength λ nm is incident from each inclined direction, and a total of 6 points are measured, and the measured retardation value KOBRA 21ADH or WR is calculated based on the assumed average refractive index and the input film thickness value.
In the above case, 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, retardation at a tilt angle larger than the tilt angle. The value is calculated by KOBRA 21ADH or WR after changing its sign to negative.
In addition, the retardation value is measured from the two inclined directions, with the slow axis as the tilt axis (rotation axis) (when there is no slow axis, the arbitrary direction in the film plane is the rotation axis), Based on the value, the assumed value of the average refractive index, and the input film thickness value (d), Rth can also be calculated from the following equations (1) and (2).

..... Formula (1)

Re (θ) in the above formula (1) represents a retardation value in a direction inclined by an angle θ from the normal direction.
In formula (1), nx represents the refractive index in the slow axis direction in the plane, ny represents the refractive index in the direction perpendicular to nx in the plane, and nz represents the refractive index in the direction perpendicular to nx and ny. .
Rth = ((nx + ny) / 2−nz) × d (2)
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 is calculated by the following method. Rth is the Re in 10 degree steps from −50 degrees to +50 degrees with respect to the normal direction of the film, with the in-plane slow axis (determined by KOBRA 21ADH or WR) as the tilt axis (rotation axis). 11 points of light having a wavelength of λ nm are incident from the inclined direction, and KOBRA 21ADH or WR is calculated based on the measured retardation value, the assumed value of the average refractive index, and the input film thickness value.
From this calculated nx, ny, nz, Nz = (nx−nz) / (nx−ny) is further calculated. In this specification, unless otherwise specified, the measurement wavelength is 590 nm, and the measurement value is 25 ° C. and 60% RH.

Hereinafter, the polarizing plate of the present invention will be described in detail. In the present invention, curling can be controlled by controlling the hygroscopic expansion coefficient of the protective film on both surfaces of the polarizing plate within a specific range, which can contribute to improvement of productivity.
In addition, by controlling the moisture permeability of one of the protective films of the polarizing plate of the present invention within a specific range, non-uniform light leakage due to humidity changes during long-term use can be prevented when incorporated into a liquid crystal display device. can do.
Furthermore, the polarizing plate of the present invention preferably has a retardation film, which eliminates image coloring of the liquid crystal display device and contributes to the expansion of the viewing angle.

(Polarizer)
In the polarizing plate of the present invention, a protective film (A) based on a polymer film (a) is laminated on one surface of a polarizing film, and a protective film (A) based on a polymer film (b) on the other surface ( B) is laminated, the moisture permeability of the protective film (A) is 200 g / m ² · day or less, and the difference in the hygroscopic expansion coefficient between the protective film (A) and the protective film (B) is 10 ppm /% RH or less. It is characterized by being.
In the present invention, the protective film (A) and the protective film (B) each contain one polymer film. A form in which a plurality of polymer films are bonded with an adhesive or the like is not included.

The polarizing plate of the present invention is preferably in the form of a long roll. By controlling the physical properties of the protective film (A) and the protective film (B) as described above, the protective film (A) and the protective film are changed to the change film. After bonding (B), curling in the conveying process from drying to winding can be prevented.
The length of the roll is preferably 10 m or more, more preferably 50 m or more, and further preferably 100 m or more.
Further, the width of the roll is preferably 50 cm or more, more preferably 80 cm or more, and further preferably 100 cm or more. The lift at both ends due to the difference in the hygroscopic expansion coefficient increases as the width increases, and becomes apparent at 50 cm or more, and the present invention becomes important.

<Polarizing film>
Next, the polarizing film used in the polarizing plate and the liquid crystal display device of the present invention will be described in detail.
A polarizing film in particular is not restrict | limited, A well-known thing can be employ | adopted widely. For example, dichroic dyes such as iodine and / or azo, anthraquinone, tetrazine and the like on films made of hydrophilic polymers such as polyvinyl alcohol, partially formalized polyvinyl alcohol, and partially saponified ethylene / vinyl acetate copolymer For example, a material obtained by adsorbing a dichroic material composed of the above and the like and performing a stretching orientation treatment can be used.

The polarizing plate usually has a form in which at least one surface of the polarizing film is protected by a transparent protective film (also referred to as a protective film).
The kind of transparent protective film is not particularly limited, and cellulose esters such as cellulose acetate, cellulose acetate butyrate, and cellulose propionate, polycarbonate, polyolefin, polystyrene, polyester, and the like are used.
The transparent protective film is usually supplied in a roll form, and it is preferable from the viewpoint of productivity that the transparent protective film is continuously bonded to the long polarizing film so that the longitudinal directions thereof coincide.

<Protective film>
In this invention, a protective film (A) and a protective film (B) are laminated | stacked as a transparent protective film on both surfaces of a polarizing layer. The thickness of the protective film (A) and the polymer film (a) as the base material of the protective film (B) and the polymer film (b) are preferably 20 to 200 μm, more preferably 25 to 150 μm. It is preferably 30 to 120 μm, more preferably 35 to 100 μm.

The moisture permeability of the protective film (A) is preferably 200 g / m ² · day or less, so that when incorporated in a liquid crystal display device, light leakage or color at the time of black display due to a change in humidity of the image display device. Change can be prevented.

In the present invention, it is further necessary that the difference between the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) is 10 ppm /% RH or less. If this range is exceeded, when the storage humidity changes in the state of the polarizing plate, the expansion coefficient of the protective film (A) and the expansion coefficient of the protective film (B) are different, which causes a problem of curling of the polarizing plate.
The difference between the hygroscopic expansion coefficients of the protective film (A) and the protective film (B) is more preferably 7 ppm /% RH or less, further preferably 5 ppm /% RH or less, and 3 ppm /% RH or less. Is particularly preferred.

In the present invention, the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) are both preferably 50 ppm /% RH or less, more preferably 30 ppm /% RH or less, More preferably, it is 15 ppm /% RH or less.
By setting both the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) to 50 ppm /% RH or less, the hygroscopic expansion of the entire polarizing plate can be reduced and attached to the liquid crystal cell. It is possible to prevent liquid crystal cell distortion when combined and light leakage due to liquid crystal cell distortion.

In the present invention, the hygroscopic expansion coefficient means the dimensional change rate of the film when the environment is changed from 25 ° C. 20% RH to 25 ° C. 80% RH. That is, when the film size at 25 ° C. and 20% RH is L ₂₀ , and the size at 25 ° C. and 80% RH is L ₈₀ , [[(L ₈₀ −L ₂₀ ) / L ₂₀ ] / (80 −20)] × 10 ⁶ is the hygroscopic expansion coefficient (unit: ppm /% RH). For example, the film can be obtained by cutting the film into a rectangle having a width of 5 cm and a length of 28 cm and measuring the film length at 25 ° C., 20% RH and 25 ° C., 80% RH.

The hygroscopic expansion coefficient of the protective film can be adjusted by appropriately selecting the kind and amount of the film material and the additive to the film.
Specifically, a cellulose acylate film containing a specific deterioration inhibitor, a cellulose acylate film containing a chlorinated organic solvent content, a cellulose acylate film containing a specific polyhydric alcohol ester, and a cyclic shape Polyolefin film or polycarbonate can be used as a protective film.

<Protective film (A)>
As a method for controlling the moisture permeability of the protective film (A) to 200 g / m ² · day or less, as a polymer film (a) that is a base material of the protective film (A), And a method of providing a moisture-proof layer on a film substrate having a moisture permeability of more than 200 g / m ² · day. In the present invention, it is preferable to select a polymer film having a low moisture permeability.

<< Measurement of moisture permeability >>
The measurement method of moisture permeability is "Polymer Physical Properties II" (Polymer Experiment Course 4, Kyoritsu Shuppan), pages 285-294: Measurement of vapor permeation (mass method, thermometer method, vapor pressure method, adsorption amount method) The film sample of 70 mmφ according to the present invention was conditioned at 60 ° C. and 95% RH for 24 hours, respectively, and from the mass difference before and after the humidity adjustment, according to JIS Z-0208, per unit area Was calculated (g / m ² ).
The moisture permeability of a commercially available cellulose acetate film measured by the above measurement method is generally 80 μm in thickness and 1,400 to 1,500 g / m ² · day under the above conditions.
The upper limit of the moisture permeability of the protective film of the present invention is preferably 300 g / m ² · day or less, more preferably 200 g / m ² · day or less, and 150 g / m ² · day or less. Further preferred. If the moisture permeability is higher than the above upper limit value, unevenness of the display image occurs due to a change in the size of the polarizing film due to a change in temperature or humidity during long-term use, and the reduction effect is low. There is no particular lower limit.

<< Base material >>
[Polymer film (a)]
The protective film (A) for the polarizing plate of the present invention is based on the polymer film (a). In this case, the protective film (A) may be the polymer film (a) itself, or the polymer film (a) is the base material of the protective film (A) and the functional layer is preferably laminated. . There may be a plurality of functional layers.
In the present invention, examples of a preferable functional layer that can be contained in the protective film (A) include a moisture-proof layer, a hard coat layer, an anti-glare layer, an anti-reflection layer, and an easy adhesion layer.

The polymer film (a) has a moisture permeability of 200 g / m ² · day or less, and is preferably a thermoplastic resin from the viewpoint of mechanical strength and molding processability. Examples of such thermoplastic resins include polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polymethylpentene, polysulfone, and alicyclic structure-containing polymer resins.

  From the ease of polarizing plate processing, a cellulose acylate film with a moisture-proof layer is used as the protective film (A), and a polymer film (b) that is a base material of the protective film (B) described later is a cellulose acylate film. A retardation film can be used.

<< Dampproof layer >>
The moisture-proof layer that can be used for the protective film (A) of the present invention is not particularly limited as long as the water vapor transmission rate can be 200 g / m ² · day or less. For example, JP 2006-12317 A [0096] to The moisture-proof layer described in [0119] can be used.
The moisture-proof layer may be provided on the surface of the base film close to the polarizing film or on the surface far from the polarizing film. It is easy to remove and is preferable.

The moisture-proof layer that can be used for the protective film (A) of the present invention preferably has a polymer containing a repeating unit derived from chlorine-containing vinyl (hereinafter also referred to as chlorine-containing polymer).
In general, examples of the chlorine-containing vinyl monomer include vinyl chloride and vinylidene chloride.
A chlorine-containing polymer can be obtained by copolymerizing these vinyl chloride or vinylidene chloride monomers with a monomer copolymerizable therewith.

[Monomer copolymerizable with chlorine-containing vinyl monomer]
Examples of the copolymerizable monomer include olefins, styrenes, acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, itaconic acid diesters, maleic acid esters, fumaric acid diesters, N- Examples thereof include monomers selected from alkylmaleimides, maleic anhydride, acrylonitrile, vinyl ethers, vinyl esters, vinyl ketones, vinyl heterocyclic compounds, glycidyl esters, unsaturated nitriles, unsaturated carboxylic acids and the like.

Examples of olefins include dicyclopentadiene, ethylene, propylene, 1-butene, 1-pentene, isoprene, chloroprene, butadiene, 2,3-dimethylbutadiene and the like.
Examples of styrenes include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, isopropyl styrene, chloromethyl styrene, methoxy styrene, acetoxy styrene, chloro styrene, dichloro styrene, bromo styrene, trifluoromethyl styrene, vinyl. And benzoic acid methyl ester.

Specific examples of acrylic esters and methacrylic esters include the following.
Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, t-octyl acrylate, 2-methoxyethyl acrylate, 2-butoxyethyl acrylate, 2-phenoxyethyl acrylate, chloroethyl acrylate, Cyanoethyl acrylate, dimethylaminoethyl acrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, oct Methacrylate, benzyl methacrylate, cyanoacetoxyethyl methacrylate, chlorobenzyl methacrylate, sulfopropyl methacrylate, N-ethyl-N-phenylaminoethyl methacrylate, 2-methoxyethyl methacrylate, 2- (3-phenylpropyloxy) ethyl methacrylate, dimethylamino Phenoxyethyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, phenyl methacrylate, cresyl methacrylate, naphthyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, 3 -Chloro-2-hydro Cypropyl methacrylate, 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, diethylene glycol monoacrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, 5-hydroxypropyl Methacrylate, diethylene glycol monomethacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate.

Specific examples of vinyl ethers include the following.
Methyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethyl hexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2-ethylbutyl ether, dimethylaminoethyl Vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether, vinyl phenyl ether, vinyl tolyl ether, vinyl chlorophenyl ether, vinyl-2,4-dichlorophenyl ether, vinyl naphthyl ether, vinyl anthranyl ether .

Specific examples of the vinyl esters include the following.
Vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl dimethyl propionate, vinyl ethyl butyrate, vinyl valerate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxyacetate, Vinyl butoxy acetoacetate, vinyl phenyl acetate, vinyl acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinyl cyclohexyl carboxylate, vinyl benzoate, vinyl salicylate, vinyl chlorobenzoate, vinyl tetrachlorobenzoate, vinyl naphthoate.

  Acrylamides include acrylamide, methylacrylamide, ethylacrylamide, propylacrylamide, butylacrylamide, t-butylacrylamide, cyclohexylacrylamide, benzylacrylamide, hydroxymethylacrylamide, methoxyethylacrylamide, dimethylaminoethylacrylamide, phenylacrylamide, dimethylacrylamide, and diethyl. Examples include acrylamide, β-cyanoethyl acrylamide, and N- (2-acetoacetoxyethyl) acrylamide.

  Examples of methacrylamides include methacrylamide, methyl methacrylamide, ethyl methacrylamide, propyl methacrylamide, butyl methacrylamide, tert-butyl methacrylamide, cyclohexyl methacrylamide, benzyl methacrylamide, hydroxymethyl methacrylamide, methoxyethyl methacrylamide , Dimethylaminoethylmethacrylamide, phenylmethacrylamide, dimethylmethacrylamide, diethylmethacrylamide, β-cyanoethylmethacrylamide, N- (2-acetoacetoxyethyl) methacrylamide and the like.

  Further, acrylamides having a hydroxyl group can be used, and examples thereof include N-hydroxymethyl-N- (1,1-dimethyl-3-oxo-butyl) acrylamide, N-methylol acrylamide, N-methylol methacryl. Examples include amide, N-ethyl-N-methylol acrylamide, N, N-dimethylol acrylamide, N-ethanol acrylamide, N-propanol acrylamide, N-methylol acrylamide and the like.

  Examples of the itaconic acid diesters include dimethyl itaconate, diethyl itaconate, and dibutyl itaconate. Examples of maleic acid diesters include diethyl maleate, dimethyl maleate, and dibutyl maleate. Examples of the fumaric acid diesters include diethyl fumarate, dimethyl fumarate, dibutyl fumarate and the like.

  Examples of vinyl ketones include methyl vinyl ketone, phenyl vinyl ketone, methoxyethyl vinyl ketone, and the like. Examples of the vinyl heterocyclic compound include vinyl pyridine, N-vinyl imidazole, N-vinyl oxazolidone, N-vinyl triazole, and N-vinyl pyrrolidone. Examples of glycidyl esters include glycidyl acrylate and glycidyl methacrylate. Examples of unsaturated nitriles include acrylonitrile and methacrylonitrile. Examples of N-alkylmaleimides include N-ethylmaleimide and N-butylmaleimide.

  Examples of the unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid and the like, and further anhydrides such as fumaric acid, itaconic acid and maleic acid. Two or more kinds of these copolymerizable monomers may be used.

  Examples of the chlorine-containing polymer in the present invention include JP-A-53-58553, JP-A-55-43185, JP-A-57-139109, JP-A-57-139136, JP-A-60. -235818, JP-A 61-108650, JP-A 62-256871, JP-A 62-280207, JP-A 63-256665, and the like.

  The proportion of the chlorine-containing vinyl monomer in the chlorine-containing polymer is preferably 50 to 99% by mass, more preferably 60 to 98% by mass, and most preferably 70 to 97% by mass. If the ratio of the chlorine-containing vinyl monomer is 50% or more, problems such as deterioration of moisture permeability will not occur, and if it is 99% or less, solubility in various solvents is obtained, which is preferable. .

Chlorine-containing polymers are available from Asahi Kasei Chemicals Corporation and Kureha Chemical Corporation. The following are listed as available from Asahi Kasei Chemicals Corporation.
“Saran Resin R241C”, “Saran Resin F216”, “Saran Resin R204”, “Saran Latex L502”, “Saran Latex L529B”, “Saran Latex L536B”, “Saran Latex L544D”, “Saran Latex L549B”, “Saran Latex L551B” “Saran Latex L557”, “Saran Latex L561A”, “Saran Latex L116A”, “Saran Latex L411A”, “Saran Latex L120”, “Saran Latex L123D”, “Saran Latex L106C”, “Saran Latex L131A”, “ “Saran Latex L111”, “Saran Latex L232A”, “Saran Latex L321B”. In particular, Saran Resin F216 and Saran Resin R204 are more preferably used because they are soluble in ketone solvents (such as methyl ethyl ketone and cyclohexanone).

  The thickness of the moisture-proof layer is preferably 0.5 to 10 μm, more preferably 1 to 8 μm, and most preferably 1.5 to 5 μm. It is preferable that the thickness of the moisture-proof layer is not more than the upper limit value because it has excellent low moisture permeability and does not cause adverse effects such as an increase in curl. If the curl becomes too large, it will hinder subsequent processes for producing a polarizing plate, for example, a bonding process with a polarizing film and handling. Further, not only the manufacturing process but also the curling of the polarizing plate is not preferable because it causes display unevenness in the LCD. Therefore, in order to reduce the curl so that it does not occur or is practically not problematic, the upper limit of the coating layer thickness is preferably within the above range. Moreover, if it is below this upper limit value, since it does not produce bad effects, such as becoming a brittle film | membrane and becoming easy to color, it is preferable. On the other hand, the lower limit of the film thickness is defined as a range that is more preferable than moisture resistance, and the effect of the present invention can be sufficiently exhibited by setting the above range. The coating layer consists of at least one layer, and two or more layers are also possible.

  The haze of the moisture-proof layer is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less. The ratio between the surface haze and the internal haze may be arbitrary, but the internal haze is more preferably 1% or less.

Since the moisture-proof layer of the present invention is often wet-coated, the solvent used in the coating composition is an important factor. Requirements include that the above solute is sufficiently dissolved and that coating unevenness and drying unevenness are less likely to occur during the drying process.
In order to form a mixed region between the support and the moisture-proof layer, a solvent having a property of dissolving or swelling the base film is selected as the solvent of the coating solution for forming the moisture-proof layer. There is a need. This is because if such a solvent is used in the coating liquid, the interface between the base film and the coating layer becomes unclear at the same time because the moisture-proof layer is formed while dissolving or swelling the support immediately after coating. The layer of the area | region which mixed the resin component of this and the resin component of the base film is formed.

<< Hard coat layer >>
In order to give the physical strength of the film to the protective film (A) of the present invention, preferably a layer having a hard coat property on the surface of the polymer film (a) on which the polarizing film is not bonded (hereinafter referred to as a hard coat layer). May be described).
Further, it is preferable that a low refractive index layer is provided on the hard code layer, and an intermediate refractive index layer and a high refractive index layer are provided between the hard coat layer and the low refractive index layer to constitute an antireflection film. It is more preferable.
The hard coat layer may be composed of a laminate of two or more layers.

  The refractive index of the hard coat layer in the present invention is preferably in the range of 1.48 to 2.00 from the viewpoint of reducing the difference in refractive index from the base film and preventing interference unevenness. It is more preferably 49 to 1.90, and further preferably 1.50 to 1.80.

The thickness of the hard coat layer is preferably about 0.5 to 50 μm, more preferably 1 to 20 μm, still more preferably 2 to 15 μm, from the viewpoint of imparting sufficient durability and impact resistance to the film. Is particularly preferred.
Further, the strength of the hard coat layer is preferably 2H or more, more preferably 3H or more, and further preferably 4H or more in the pencil hardness test.
Furthermore, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.

The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. For example, a coating composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is applied on a transparent substrate film, and the polyfunctional monomer or polyfunctional oligomer is formed by a crosslinking reaction or a polymerization reaction. Can do.
The functional group of the ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.
Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable.

Instead of or in addition to the monomer having a polymerizable unsaturated group, a crosslinkable functional group may be introduced into the binder.
Examples of the crosslinkable functional group include isocyanate group, epoxy group, aziridine group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, methylol group and active methylene group. Vinylsulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester and urethane, and metal alkoxide such as tetramethoxysilane can also be used as a monomer having a crosslinked structure. A functional group that exhibits crosslinkability as a result of the decomposition reaction, such as a block isocyanate group, may be used.
That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition. These binders having a crosslinkable functional group can form a crosslinked structure by heating after coating.

  The hard coat layer contains matte particles having an average particle size of 1.0 to 10.0 μm, preferably 1.5 to 7.0 μm, such as inorganic compound particles or resin particles, for the purpose of imparting internal scattering properties. May be.

For the purpose of controlling the refractive index of the hard coat layer, a high refractive index monomer, inorganic particles, or both can be added to the binder of the hard coat layer. In addition to the effect of controlling the refractive index, the inorganic particles also have the effect of suppressing cure shrinkage due to the crosslinking reaction.
In the present invention, a polymer formed by polymerizing the polyfunctional monomer and / or the high refractive index monomer after the formation of the hard coat layer, and the inorganic particles dispersed therein are referred to as a binder.

The haze of the hard coat layer varies depending on the function imparted to the protective film.
When maintaining the sharpness of the image, suppressing the reflectance of the surface, and not imparting the light scattering function inside and on the surface of the hard coat layer, the haze value is preferably as low as possible, specifically 10% or less is preferable, 5% or less is more preferable, and 2% or less is still more preferable.

On the other hand, in addition to the function of imparting physical strength, in the case of imparting an antiglare function by surface scattering of the hard coat layer, the surface haze is preferably 5 to 15%, preferably 5 to 10%. More preferably.
In addition, when it is difficult to see the pattern, color unevenness, brightness unevenness, glare, etc. of the liquid crystal panel due to internal scattering of the hard coat layer, or to add the function of expanding the viewing angle by scattering, the internal haze value (from the total haze value) The value obtained by subtracting the surface haze value) is preferably 10 to 90%, more preferably 15 to 70%, still more preferably 20 to 50%.
The film of the present invention can freely set surface haze and internal haze according to the purpose.

In addition, for the surface irregularity shape of the hard coat layer, in order to obtain a clear surface for the purpose of maintaining the sharpness of the image, among the characteristics indicating the surface roughness, for example, the centerline average roughness (Ra) is set. The thickness is preferably 0.10 μm or less, more preferably 0.09 μm or less, and still more preferably 0.08 μm or less.
In the film of the present invention, the surface unevenness of the film is dominant in the surface unevenness of the film, and the centerline average roughness of the protective film is adjusted by adjusting the centerline average roughness of the hardcoat layer. It can be set as the said range.

  In order to maintain the sharpness of the image, it is preferable to adjust the clarity of the transmitted image in addition to adjusting the uneven shape of the surface. The clear image of the transparent image is preferably 60% or more. The transmitted image clarity is generally an index indicating the degree of blurring of an image reflected through a film, and the larger this value, the clearer and better the image viewed through the film. The transmitted image definition is preferably 70% or more, and more preferably 80% or more.

<Protective film (B)>
The protective film (B) for the polarizing plate of the present invention is based on the polymer film (b). In this case, the protective film (B) may be the polymer film (b) itself, or the polymer film (b) may be a base material of the protective film (B), and the functional layer may be laminated. . The functional layer may be plural.
Preferable functional layers that can be contained in the protective film (B) include a moisture-proof layer, an optically anisotropic layer, a liquid crystal alignment layer, and an easy adhesion layer.

<< Base material >>
[Polymer film (b)]
The polymer film (b) used in the polarizing plate of the present invention is preferably a retardation film, and includes a polymer film (a) which is a base material of the protective film (A) and a base material of the protective film (B). Considering the use of a film of the same material for a certain polymer film (b), among the above films, the polycarbonate and alicyclic structure-containing polymer resin used as the material of the retardation film are preferred.

  Specific examples of the alicyclic structure-containing polymer resin include (1) a norbornene polymer, (2) a polymer of a monocyclic olefin, (3) a polymer of a cyclic conjugated diene, and (4) a vinyl alicyclic ring. And a hydride of the above (1) to (4). Among these, from the viewpoints of heat resistance and mechanical strength, a norbornene polymer hydride, a vinyl alicyclic hydrocarbon polymer, and a hydride thereof are preferable.

<< retardation film >>
For the purpose of expanding the viewing angle of a liquid crystal display device, a retardation film is laminated on a polarizing plate and used. In this case, a method of using a polymer film having low retardation for the protective film (B) and pasting the retardation film via an adhesive, and the protective film (B) is a retardation film and the polarizing plate protective film. In the present invention, for the purpose of reducing the thickness of the liquid crystal display panel, it is preferable that the protective film (B) also functions as a retardation film and a protective film.

When the protective film (B) does not serve as a retardation film and the retardation film is bonded with an adhesive, the in-plane retardation Re of the polymer film (b) which is the base material of the protective film (B) is 10 nm or less. Is preferable, 8 nm or less is more preferable, and 5 nm or less is still more preferable.
On the other hand, when the protective film (B) also serves as a retardation film, the in-plane retardation of the polymer film (b) which is the base material of the protective film (B) is preferably −25 to 55 nm, and −25 It is more preferably ˜25 nm, and particularly preferably −10 to 10 nm.

  When the polymer film (b) is a retardation film, the in-plane retardation Re of the polymer film (b) is preferably 15 to 300 nm, or the retardation Rth in the thickness direction is preferably 60 to 400 nm. In the present invention, it is more preferred that at least the in-plane retardation Re of the polymer film (b) is 15 to 300 nm.

As a relational expression between the in-plane retardation Re and the retardation Rth in the thickness direction, when Nz in the formula (3) defined below is close to 1, the retardation film is called A plate, which is useful for optical compensation. It is preferable.
Nz = Rth / Re + 0.5 ..... Formula (3)
At this time, Nz is preferably 1.0 to 1.35, more preferably 1.0 to 1.30, and still more preferably 1.0 to 1.25.

At this time, Re is preferably 110 to 170 nm, more preferably 120 to 160 nm, and still more preferably 130 to 150 nm.
Further, regarding the measurement wavelength dependence of the in-plane retardation, the in-plane retardation becomes larger as the wavelength is longer at the measurement wavelength of 400 to 700 nm. The in-plane retardation Re (450) at the measurement wavelength of 450 nm and the in-plane letter at the measurement wavelength of 550 nm. Re (450) / Re (550), which is the ratio of the foundation Re (550), is preferably 0.70 to 0.95, more preferably 0.70 to 0.90, and 0.75 to More preferably, it is 0.85.
As an optical compensation film satisfying such conditions, Teijin Pure Ace-WR is marketed by Teijin Chemicals Ltd. In the present invention, a retardation film having such optical characteristics can be preferably used.

  When the in-plane retardation Re of the polymer film (b) is 15 to 300 nm, the slow axis of the polymer film (b) and the absorption axis of the polarizing plate are preferably orthogonal from the viewpoint of optical compensation. Moreover, since the absorption axis of the polarizing film generally used is parallel to the longitudinal direction, it is preferable that the slow axis of the polymer film is orthogonal to the longitudinal direction.

  In the present invention, a method of forming a polarizing film by transverse stretching described in JP-A No. 2002-131548 can be preferably used. In particular, it is preferable to use a width direction uniaxial stretching type tenter stretching machine in which the absorption axis of the polarizing film is substantially perpendicular to the longitudinal direction. Only in this case, the slow axis of the polymer film (b) is preferably parallel to the longitudinal direction.

[Stretching treatment]
In order to develop the in-plane retardation Re of the polymer film (b) of the present invention, the polymer film (b) is preferably stretched. A desired retardation can be imparted by a stretching treatment.
The stretching direction may be either the width direction or the longitudinal direction, but it is preferably the width direction in the normal stretching method as described above.

Methods for stretching in the width direction are described in, for example, JP-A-62-115035, JP-A-4-152125, 4-284221, 4-298310, and 11-48271. Yes. The film is stretched at room temperature or under heating conditions. The heating temperature is preferably not higher than the glass transition temperature of the film.
In the case of stretching in the longitudinal direction, for example, the film is stretched by adjusting the speed of the film transport roller so that the film winding speed is higher than the film peeling speed.
In the case of stretching in the width direction, the film can also be stretched by conveying while holding the width of the film with a tenter and gradually widening the width of the tenter. After the film is dried, it can be stretched using a stretching machine (preferably uniaxial stretching using a long stretching machine).

[Optically anisotropic layer]
As described above, the protective film (B) of the present invention can preferably contain an optically anisotropic layer. The optically anisotropic layer is preferably formed from a composition containing a liquid crystalline compound.
The optically anisotropic layer is preferably formed on an alignment film formed on the polymer film (b).
Examples of the liquid crystalline compound used for forming the optically anisotropic layer include a rod-like liquid crystalline compound and a discotic liquid crystalline compound. The liquid crystal compound may be a polymer liquid crystal. Furthermore, when an optically anisotropic layer is formed using a low molecular liquid crystal, the low molecular liquid crystal may be crosslinked in the layer so as not to exhibit liquid crystallinity.

-Rod-like liquid crystalline compound-
Examples of rod-like liquid crystalline compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines. , Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. Among them, compounds containing cyanophenyl esters and benzoic acid esters are preferable because they are easily hydrolyzed and eluted in an alkaline solution.
Not only the above low-molecular liquid crystalline compounds but also high-molecular liquid crystalline compounds can be used. It is more preferable to fix the alignment of the rod-like liquid crystal compound by polymerization. As the liquid crystalline compound, those having a partial structure capable of causing polymerization or crosslinking reaction by actinic rays, electron beams, heat, or the like are suitably used. The number of the partial structures is preferably 1 to 6, more preferably 1 to 3.
As the polymerizable rod-like liquid crystalline compound, Makromol. Chem. 190, 2255 (1989), Advanced Materials 5, 107 (1993), US Pat. No. 4,683,327, US Pat. No. 5,622,648, US Pat. No. 5,770,107, International Publication WO95 / 22586. No. 95/24455, No. 97/00600, No. 98/23580, No. 98/52905, JP-A-1-272551, No. 6-16616, and No. 7-110469. 11-80081, JP 2001-328773, JP 2004-240188, JP 2005-99236, JP 2005-99237, JP 2005-121827, JP It is possible to use the compounds described in 2002-30042 That.

-Discotic liquid crystalline compounds-
In the present invention, the optically anisotropic layer can also be formed using a discotic liquid crystal compound.
Examples of the discotic liquid crystalline compound include C.I. Destrade et al., Mol. Cryst. 71, 111 (1981), benzene derivatives described in C.I. Destrade et al., Mol. Cryst. 122, 141 (1985), Physics lett, A, 78, 82 (1990); Kohne et al., Angew. Chem. 96, 70 (1984) and the cyclohexane derivatives described in J. Am. M.M. Lehn et al. Chem. Commun. , 1794 (1985), J. Am. Zhang et al., J. Am. Chem. Soc. 116, 2655 (1994), and azacrown and phenylacetylene macrocycles.

A discotic liquid crystalline compound is a compound having a general molecular structure in which a linear alkyl group, an alkoxy group, or a substituted benzoyloxy group is substituted radially with respect to the mother nucleus at the center of the molecule. , Showing liquid crystallinity.
In the optically anisotropic layer formed from the discotic liquid crystalline compound, the substance contained in the final layer does not need to be the compound. For example, a low-molecular discotic liquid crystalline compound may have a group that reacts with heat or light, and as a result, it may be polymerized or cross-linked by reaction with heat or light to increase the molecular weight and lose liquid crystallinity.
Examples of the discotic liquid crystalline compound are described in JP-A-8-50206. The polymerization of the discotic liquid crystalline compound is described in JP-A-8-27284.

<< Surface treatment >>
The protective film (A) and the polymer film (a) and the polymer film (b), which are the base materials of the protective film (B), are optionally subjected to surface treatment, whereby the film and each functional layer (for example, Improvement of adhesion with the coating layer and the back layer) can be achieved.
As the surface treatment, for example, glow discharge treatment, ultraviolet irradiation treatment, corona treatment, flame treatment, acid or alkali treatment can be used.
The glow discharge treatment here may be low-temperature plasma that occurs under a low pressure gas of 10 ^{−3 to} 20 Torr, and plasma treatment under atmospheric pressure is also preferred.
The plasma-excitable gas is a gas that is plasma-excited under the above conditions, and includes chlorofluorocarbons such as argon, helium, neon, krypton, xenon, nitrogen, carbon dioxide, tetrafluoromethane, and the like. A mixture etc. are mentioned. Regarding these, the details are disclosed in the Invention Association Public Technical Bulletin No. 2001-1745 (issued March 15, 2001, Invention Association) p. 30-32. Note that, in the plasma treatment at atmospheric pressure which has been attracting attention in recent years, for example, irradiation energy of 20 to 500 Kgy is used under 10 to 1,000 Kev, and more preferably irradiation energy of 20 to 300 Kgy is used under 30 to 500 Kev. . When the polymer film is a cellulose acylate film, an alkali saponification treatment is particularly preferable among these, and the surface treatment of the cellulose acylate film is extremely effective.

The alkali saponification treatment is preferably carried out by a method in which the cellulose acylate film is directly immersed in a saponification solution tank or a method in which the saponification solution is applied to the cellulose acylate film.
Examples of the coating method include a dip coating method, a curtain coating method, an extrusion coating method, a bar coating method, and an E-type coating method.
The solvent of the alkali saponification coating solution has good wettability in order to apply the saponification solution to the cellulose acylate film, and the surface of the cellulose acylate film surface is not formed by the saponification solution solvent. It is preferred to select a solvent that remains good.
Specifically, an alcohol solvent is preferable, and isopropyl alcohol is particularly preferable. An aqueous solution of a surfactant can also be used as a solvent.
The alkali of the alkali saponification coating solution is preferably an alkali that dissolves in the above solvent, and more preferably KOH or NaOH.
Further, the pH of the saponification coating solution is preferably 10 or more, more preferably 12 or more. The reaction conditions during alkali saponification are preferably 1 second to 5 minutes at room temperature, more preferably 5 seconds to 5 minutes, and even more preferably 20 seconds to 3 minutes. After the alkali saponification reaction, it is preferable to wash the surface on which the saponification solution is applied with water or with an acid and then with water.

  In the polarizing plate of the present invention, it is preferable that the protective film (A) is provided with at least one layer of a hard coat layer, an antiglare layer and an antireflection layer on the surface. Each layer does not need to be provided as a separate layer. For example, an anti-glare layer is provided as an anti-glare layer and an anti-glare layer by providing the anti-reflection layer or the hard coat layer with an anti-glare function. May be.

(Liquid crystal display device)
The liquid crystal display device of the present invention includes at least the polarizing plate of the present invention. The liquid crystal display device of the present invention may be any of a reflection type, a semi-transmission type, a transmission type liquid crystal display device and the like.
A liquid crystal display device generally includes a polarizing plate, a liquid crystal cell, and a retardation plate, a reflection layer, a light diffusion layer, a backlight, a front light, a light control film, a light guide plate, a prism sheet, a color filter, and the like as necessary. Although comprised from a member, in this invention, there is no restriction | limiting in particular except the point which makes it essential to use the polarizing plate of this invention.
The liquid crystal cell is not particularly limited, and a general liquid crystal cell such as a liquid crystal layer sandwiched between a pair of transparent substrates provided with electrodes can be used.
The transparent substrate constituting the liquid crystal cell is not particularly limited as long as the liquid crystal material constituting the liquid crystal layer is aligned in a specific alignment direction. Specifically, a transparent substrate in which the substrate itself has a property of orienting liquid crystals, a transparent substrate in which an alignment film having the property of orienting liquid crystals is provided, but the substrate itself lacks the alignment ability. Either can be used.
Moreover, a well-known thing can be used for the electrode of a liquid crystal cell. Usually, it can be provided on the surface of the transparent substrate in contact with the liquid crystal layer, and when a substrate having an alignment film is used, it can be provided between the substrate and the alignment film.
The material exhibiting liquid crystallinity for forming the liquid crystal layer is not particularly limited, and examples thereof include various ordinary low-molecular liquid crystalline compounds, high-molecular liquid crystalline compounds, and mixtures thereof that can constitute various liquid crystal cells. Moreover, a pigment | dye, a chiral agent, a non-liquid crystalline compound, etc. can also be added to these in the range which does not impair liquid crystallinity.

In addition to the electrode substrate and the liquid crystal layer, the liquid crystal cell may include various components necessary for forming various types of liquid crystal cells described later.
As the liquid crystal cell system, a TN (Twisted Nematic) system, a STN (Super Twisted Nematic) system, an ECB (Electrically Controlled Birefringence) system, an IPS (In-Plane Switching) system, a VA (In-Plane Switching) system, a VA (In-Plane Switching) system, a VA (In-Plane Switching) system, a VA (In-Plane Switching) system, Alignment), PVA (Patterned Vertical Alignment), OCB (Optically Compensated Birefringence), HAN (Hybrid Aligned Nematic Asymmetric), ASM l) method, a halftone gray scale method, the domain division method or a ferroelectric liquid crystal, various methods such as a display system using an antiferroelectric liquid crystal and the like.
The driving method of the liquid crystal cell is not particularly limited, and a passive matrix method used for STN-LCD and the like, and an active matrix method using an active electrode such as a TFT (Thin Film Transistor) electrode and a TFD (Thin Film Diode) electrode, Any driving method such as a plasma addressing method may be used. A field sequential method that does not use a color filter may be used.

The polarizing plate of the present invention is preferably used for reflective, transflective, and transmissive liquid crystal display devices. A reflective liquid crystal display device usually has a configuration in which a reflector, a liquid crystal cell, and a polarizing plate are laminated in this order. The retardation plate is disposed between the reflecting plate and the polarizing film (between the reflecting plate and the liquid crystal cell or between the liquid crystal cell and the polarizing film). The reflector may share the liquid crystal cell and the substrate. As the polarizing plate, the polarizing plate of the present invention can be used. In such a case, the retardation plate may not be separately provided.
The transflective liquid crystal display device includes a liquid crystal cell, a polarizing plate disposed on the viewer side of the liquid crystal cell, and at least one retardation plate disposed between the polarizing plate and the liquid crystal cell. And at least one transflective layer disposed behind the liquid crystal layer as viewed from the viewer, and at least one retardation plate and polarizing plate behind the transflective layer as viewed from the viewer And have. In this type of liquid crystal display device, it is possible to use both a reflection mode and a transmission mode by installing a backlight. Both polarizing plates may be the polarizing plate of the present invention, or only one of them may be the polarizing plate of the present invention. When the polarizing plate of the present invention is arranged, a retardation plate may not be separately arranged between the liquid crystal cell and the polarizing plate of the present invention.

  The mode of the liquid crystal cell is not particularly limited, but is preferably an IPS mode or a VA mode.

<IPS mode>
In an IPS mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially parallel to the substrate, and the liquid crystal molecules respond in a planar manner when an electric field parallel to the substrate surface is applied.
In the IPS mode, black is displayed when no electric field is applied, and the transmission axes of the pair of upper and lower polarizing plates are orthogonal.
A method of reducing leakage light at the time of black display in an oblique direction and improving a viewing angle using an optical compensation film is disclosed in JP-A-10-54982, JP-A-11-202323, and JP-A-9-292522. No. 11-133408, No. 11-305217, No. 10-307291, and the like.

<VA mode>
In a VA mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially vertically when no voltage is applied.
The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). 176625 (in Japanese Patent Publication No. 176625), and (2) a liquid crystal cell (SID97, Digest of tech. Papers (Proceedings) 28 (1997) 845 in which the VA mode is converted into a multi-domain (for MVA mode) in order to enlarge the viewing angle. ), (3) Liquid crystal cells (n-ASM mode, CPA mode) in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied 58-59 (1998)) and (4) SURVAVAL mode liquid crystal cells (announced at LCD International 98).

  Hereinafter, the present invention will be described more specifically by way of examples. However, the embodiments of the present invention are not limited to these examples.

(Example 1)
Protective film (A), and a protective film (B) is a polycarbonate-based film, a protective film (B) was prepared polarizer P ₁ is a retardation film of the uniaxial having a slow axis in the width direction. A specific manufacturing method is described below. In addition, the functional layer is not laminated | stacked on the protective film (A) and the protective film (B).

<Preparation of the protective film _{A 1>}
As the polymer film A, a roll-shaped polycarbonate film A _{1 having} a width of 1,340 mm (Teijin Pure Ace, thickness: 80 μm, single-sided release film, hygroscopic expansion coefficient 12 ppm /% RH) was used.

<Preparation of protective film B ₁ >
A polycarbonate copolymer obtained by copolymerizing the monomer [A] represented by the following general formula (A) and the monomer [B] represented by the following general formula (B) at a ratio of 33:67 (mol%) was used.
This polycarbonate copolymer was dissolved in methylene chloride to prepare an 18% by mass dope solution.
A cast film was prepared from this dope solution, and it was transversely stretched 1.8 times on a tenter lateral stretcher at 235 ° C., and then the edge was cut to obtain a roll-shaped protective film B ₁ having a width of 1,340 mm. . The rolled protective film _{B 1} represents, a thickness of 73Myuemu, has a slow axis in the width direction, Re = 138 nm, was Rth = 80 nm.

<Production of the polarizer _{P 1>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film.
The surface of the produced protective film A ₁ is corona-treated, and is continuously bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive, and the surface is corona-treated on the other surface. _1, continuously laminated with a polyvinyl alcohol-based adhesive to prepare a polarizing plate P ₁ long it was wound. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, with the absorption axis of the polarizing film, the slow axis and the angle formed protective film B ₁ was 90 °.

The polarizer P ₁ produced was evaluated according to the following methods. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _1, after two protective film laminating, curling of the polarizing plate P ₁ between the up winding is small, there was no occurrence of wrinkles.

<Strain evaluation of glass plate after high humidity and low humidity treatment>
The glass plate prepared above was allowed to stand in an environment of 25 ° C. and 60% RH for 2 hours, and the height of the farthest position at the end of the polarizing plate was measured and recorded with reference to the surface of the table.
Subsequently, the glass plate was allowed to stand for 50 hours in an environment of 60 ° C. and 90% RH, and then left for 2 hours in an environment of 25 ° C. and 60% RH. The height of the remote location was measured. A value obtained by subtracting a value measured before processing in an environment of 60 ° C. and 90% RH from this value was defined as a glass plate strain value.

<Measurement of curl>
The produced polarizing plate was punched into a rectangle having an absorption axis direction of 305 mm and a transmission axis direction of 230 mm. Place the surface with the end raised on a flat table and leave it in an environment of 25 ° C. and 60% RH for 2 hours or more. I measured it.
Here, as an index for specifying the direction of curling, + (plus) was used when the surface was affixed to the liquid crystal cell (adhesive coating surface) side, and + (minus) when the surface was convex.

<Wrinkles during handling>
When the polarizing plate was prepared, the number of wrinkles generated by curling per 100 m of polarizing plate after the two protective films were bonded and before winding was shown.

(Example 2)
Protective film (A), and a protective film (B) is a norbornene-based film, a protective film (B) was prepared a polarizing plate P ₂ is a retardation film of biaxial having a slow axis in the width direction. A specific manufacturing method is described below. In addition, the functional layer is not laminated | stacked on the protective film (A) and the protective film (B).

<Preparation of the protective film _{A 2>}
Using a hot air dryer in which air is passed through pellets of a norbornene-based polymer (trade name: ZEONOR 1420R, manufactured by Nippon Zeon Co., Ltd., glass transition temperature: 136 ° C., saturated water absorption: less than 0.01% by mass). And dried at 110 ° C. for 4 hours.
Then, a short-axis extruder having a coat hanger type T-die having an average surface roughness Ra = 0.04 μm, in which a leaf disk-shaped polymer filter (filtration accuracy 30 μm) is installed, and the tip of the die lip is chrome-plated is used. The pellets were melt extruded at 260 ° C. to obtain a long protective film A ₂ having a thickness of 80 μm and a width of 1,340 mm. Saturated water absorption of the resulting long protective film A ₂ was below 0.01 wt%. The in-plane retardation value (Re) was 2 nm.

<Preparation of the protective film _{B 2>}
In melt extrusion of the same method as the protective film _{A 2,} alicyclic structure-containing polymer (ZEONOR1420, Nippon Zeon Co., Ltd .; glass transition temperature 136 ° C.) consisting width 1,340Mm, the average thickness of 80μm A polymer film was obtained.
Further, this polymer film was stretched transversely at a stretch ratio of 30% using a tenter, the end was cut, the width was 1,340 mm, the average thickness was 68 μm, the in-plane retardation (Re) was 35 nm, the thickness direction retardation (Rth) to obtain a protective film _{B 2} of 130 nm.

<Production of polarizing plate _{P 2>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. The surface of the produced protective film A ₂ is corona-treated, and the protective film B ₂ whose surface is corona-treated is continuously bonded to the other surface using a polyvinyl alcohol-based adhesive. ₂ was produced. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, and the slow axis of the protective film B ₂ and the absorption axis of the polarizing film is the angle was 90 °.

The polarizer P ₂ produced was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when the polarizing plate P ₂ produced, after two protective film laminating, curling of the polarizing plate P ₂ between the up winding is small, there was no occurrence of wrinkles.

(Example 3)
Protective Film (A) is a norbornene-based film, a protective film (B) was prepared a polarizing plate P ₃ is a retardation film of the uniaxial having a slow axis in the width direction of the polycarbonate. A specific manufacturing method is described below. In addition, the functional layer is not laminated | stacked on the protective film (A) and the protective film (B).

<Production of polarizing plate _{P 3>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. The protective film A ₂ surface prepared in the above Example 2 was corona treated, with continuously bonded with a polyvinyl alcohol adhesive to one surface of the polarizing film, on the other surface, in Example 1 the prepared protective film B ₁ surface was corona treated, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P ₃ long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, and the slow axis of the protective film B ₁ and the absorption axis of the polarizing film is the angle was 90 °.

The polarizer P ₃ produced was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _3, after two protective film laminating, curling of the polarizing plate P ₃ between the up winding is small, there was no occurrence of wrinkles.

Example 4
Protective Film (A) is a polycarbonate film, a protective film (B) was prepared polarizing plate P ₄ is a phase difference film of biaxial having a slow axis in the width direction of norbornene. A specific manufacturing method is described below. In addition, the functional layer is not laminated | stacked on the protective film (A) and the protective film (B).

<Production of polarizing plate _{P 4>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. The surface of the protective film A ₁ produced in Example 1 is corona-treated, and continuously bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive. the prepared protective film B ₂ of the surface was corona treated, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P ₄ long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, and the slow axis of the protective film B ₂ and the absorption axis of the polarizing film is the angle was 90 °.

The polarizing plate P ₄ produced was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizing plate P _4, after two protective film laminating, curling of the polarizing plate P ₄ between the up winding is small, there was no occurrence of wrinkles.

(Example 5)
Protective film (A), and a protective film (B) is a polycarbonate-based film, a protective film (B) was prepared polarizer P ₅ is a retardation film having only retardation substantially the thickness direction. A specific manufacturing method is described below. In addition, the functional layer is not laminated | stacked on the protective film (A) and the protective film (B).

<Preparation of the protective film _{B 3>}
Bisphenol A type polycarbonate (C1400 manufactured by Teijin Chemicals Ltd.) was dissolved in methylene chloride to prepare a dope solution having a solid concentration of 18% by mass.
From this dope solution, a film flow was produced on a support by a solution casting method. This was peeled from the support and dried by gradually raising the temperature to Tg-20 ° C. to obtain a film.
Subsequently, this film was biaxially stretched 1.1 times in length and width at 165 ° C. to obtain a protective film B ₃ .
The resulting width of the protective film _{B 3} is 1,200mm, the thickness was 80 [mu] m. The in-plane retardation (Re) was 0 nm and the thickness direction retardation (Rth) was 250 nm.

<Production of polarizing plate _{P 5>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. The surface of the protective film A ₁ produced in Example 1 is corona treated, and continuously bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive, and the surface is corona treated on the other surface. the protective film B ₃ that, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P ₅ long.

The polarizer P ₅ produced was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _5, after two protective film laminating, curling of the polarizing plate P ₅ between the up winding is small, there was no occurrence of wrinkles.

(Example 6)
In the first embodiment, as a protective film (B), except for using the polycarbonate-based film in the longitudinal stretching in place of the polycarbonate-based film in the transverse stretching in the same manner as in Example 1 to prepare a polarizing plate P _6. A specific manufacturing method is described below.

<Preparation of the protective film _{B 5>}
A polycarbonate copolymer obtained by copolymerizing the monomer [A] represented by the general formula (A) and the monomer [B] represented by the general formula (B) at a ratio of 33:67 (mol%) was used.
This polycarbonate copolymer was dissolved in methylene chloride to prepare an 18% by mass dope solution.
A cast film was prepared from this dope solution and longitudinally stretched 1.8 times at 235 ° C., and then the edge was cut to obtain a roll-shaped protective film B ₅ having a width of 1,340 mm. The rolled protective film _{B 5} is a thickness of 73μm, has a slow axis in the longitudinal direction, Re = 138 nm, was Rth = 80 nm.

<Production of polarizing plate _{P 6>}
In the preparation of the polarizing plate P ₁ of the first embodiment, the protective film B _1, except that instead of the protective film B _5, in the same manner as in Example 1 to prepare a polarizing plate P ₆ long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, with the absorption axis of the polarizing film, the slow axis and the angle formed polymer film B ₅ was 0 °.

The polarizer P ₆ produced were evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _6, after two protective film laminating, curling of the polarizing plate P ₆ between the up winding is small, wrinkles slightly occurred.

(Example 7)
In the first embodiment, as a protective film (A), except that PET film was used instead of the polycarbonate-based film, in the same manner as in Example 1 to prepare a polarizing plate P _7. A specific manufacturing method is described below.

<Preparation of the protective film _{A 3>}
<< Raw resin synthesis >>
[Synthesis of polyethylene terephthalate containing sulfonic acid groups]
Polyester S containing a sulfonic acid group was synthesized by the following method.
To 100 parts by mass of dimethyl terephthalate and 64 parts by mass of ethylene glycol, 0.1 part by mass of calcium acetate hydrate was added, and a transesterification reaction was performed by a conventional method.
To the obtained product, 35 parts by mass of ethylene glycol solution (concentration 31% by mass) of 5-sodium sulfodi (β-hydroxyethyl) isophthalic acid (6.3 mol% / total dicarboxylic acid component), polyethylene glycol (number average) 5.8 parts by mass (molecular weight 3,000) (5% by mass / generated polyester), 0.05 parts by mass of antimony trioxide, and 0.13 parts by mass of trimethyl phosphate were added.
Next, the temperature was gradually raised and the pressure was reduced, and polymerization was carried out at 280 ° C. and 40 Pa to obtain polyester (polyethylene terephthalate) S.

[Production of polyester film]
The polyester A chip material was dried to a water content of 50 ppm or less in a Henschel mixer and a paddle dryer dryer, and then melted in an extruder set at a heater temperature of 280 to 300 ° C.
The melted polyester resin was discharged onto a chiller roll electrostatically applied from the die part to obtain an amorphous base.
After stretching the amorphous base draw ratio 3.3 times the base flow direction it was stretched to the stretching ratio 3.9 times the base width direction, to prepare a polyester film a ₃ protective film A ₃ having a thickness of 100μm .

[Formation of undercoat layer]
As a bonding surface to one surface of a polyester film a _3, performs corona discharge treatment, the following coating liquid dry film thickness. The coating is 90 nm, subbing layer (SS1) was laminated.

[Undercoat layer SS1 composition]
・ Styrene butadiene latex (solid content 43%) 300g
・ 2,4-Dichloro-6hydroxy-s-triazine sodium salt (8%) 49 g
・ Distilled water 1,600g

[Hydrophilic polymer layer SS2]
Furthermore, after coating and drying the undercoat layer SS1, a corona discharge treatment is performed on the undercoat layer SS1 coating layer, and the following coating solution is applied to a dry film thickness of 100 nm, and a hydrophilic polymer layer SS2 is laminated. to obtain a protective film _{a 3.}

[Hydrophilic polymer layer SS2 composition]
・ Gelatin 30g
・ Acetic acid (20%) 20g
・ Distilled water 1,900g

<Production of polarizing plate _{P 7>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film.
Protective film to SS2 alms surface of the protective film A ₃ prepared above, on one side of the polarizing film with continuously bonded with a polyvinyl alcohol adhesive, the other surface, the surface was corona treated B ₁ was continuously bonded using a polyvinyl alcohol-based adhesive to produce a long polarizing plate P ₇ and wound up. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, with the absorption axis of the polarizing film, the slow axis and the angle formed protective film B ₁ was 90 °.

The polarizer P ₇ produced was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _7, after two protective film laminating, curling of the polarizing plate P ₇ between the up winding is small, there was no occurrence of wrinkles.

(Example 8)
The protective film (A) is an antiglare hard coat film based on a polycarbonate film, and the protective film (B) is a polycarbonate film and has a uniaxial property having a slow axis in the width direction. A polarizing plate as a retardation film was produced.

<Preparation of the protective film _{A 4>}
<< Formation of Light Scattering Layer >>
[Preparation of Sol Liquid a-1]
In a 1,000 mL reaction vessel equipped with a thermometer, a nitrogen inlet tube, and a dropping funnel, 187 g (0.80 mol) of acryloxyoxypropyltrimethoxysilane, 27.2 g (0.20 mol) of methyltrimethoxysilane, 320 g of methanol ( 10 mol) and 0.06 g (0.001 mol) of KF were charged, and 15.1 g (0.86 mol) of water was slowly added dropwise at room temperature with stirring. After completion of the dropwise addition, the mixture was stirred at room temperature for 3 hours, and then heated and stirred for 2 hours under methanol reflux.
Then, 120g of sol liquid a-1 was obtained by depressurizingly distilling a low boiling point part and further filtering. As a result of GPC measurement of the substance thus obtained, the mass average molecular weight was 1,500, and among the components higher than the oligomer component, the component having a molecular weight of 1,000 to 20,000 was 30%.
Moreover, from the measurement result of ¹ H-NMR, the structure of the obtained substance was a structure represented by the following structural formula.

Furthermore, the condensation rate α as determined by ²⁹ Si-NMR was 0.56. From this analysis result, it was found that the silane coupling agent sol was mostly composed of a linear structure.
From the gas chromatography analysis, the raw material acryloxypropyltrimethoxysilane had a residual rate of 5% or less.

<< Preparation of coating solution for light scattering layer >>
A coating solution having the following composition was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating solution A-1 for a light scattering layer.

[Composition of coating liquid A-1 for light scattering layer (antiglare hard coat layer)]
・ PET-30 50.0g
・ Irgacure 184 2.0g
・ SX-350 (30%) 1.5g
・ Crosslinked acrylic-styrene particles (30%) 13.0 g
・ FP-1 0.75g
・ Sol liquid 1 9.5g
・ Toluene 38.5g

The compounds used in the light scattering layer coating solution are shown below.
PET-30: A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (manufactured by Nippon Kayaku Co., Ltd.)
・ Irgacure 184: Polymerization initiator (Ciba Specialty Chemicals Co., Ltd.)
SX-350: average particle size 3.5 μm cross-linked polystyrene particles (refractive index 1.60, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, used after dispersion for 20 minutes at 10,000 rpm with a Polytron disperser)
Crosslinked acrylic-styrene particles: average particle size 3.5 μm (refractive index 1.55, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, used after dispersion for 20 minutes at 10,000 rpm with a Polytron disperser)
FP-1: Fluorine-based surface modifier represented by the following structural formula

[Coating of hard coat layer]
As the polymer film A, a roll-like polycarbonate film having a width of 1,340 mm (Teijin Pure Ace, thickness: 80 μm, single-sided release film) is unwound in a roll form, and the release film is peeled off, and the release film is peeled off. The hard coat layer coating liquid A-1 is directly applied to the surface with a microgravure roll having a diameter of 135 lines / inch and a gravure pattern with a depth of 60 μm and a doctor blade at a conveyance speed of 10 m / min. Then, after drying at 60 ° C. for 150 seconds, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge, an ultraviolet ray having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² was irradiated to cure the coated layer, winding takes to prepare the elongated protective film a _4.

<Fabrication of the polarizer _{P 8>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film.
The surface not laminated a hard coat layer of the protective film A ₄ prepared above was corona treated on the other surface, the protective film B ₁ was corona treated surface, continuously attached by using a polyvinyl alcohol-based adhesive combined, to produce a polarizing plate P ₈ long was wound. At this time, the absorption axis of the polarizing film was parallel to the longitudinal direction, and the angle formed by the absorption axis of the polarizing film and the slow axis of the protective film B1 was 90 °.

The polarizer P ₈ prepared was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _8, after two protective film laminating, curling of the polarizing plate P ₈ in until the winding is small, there was no occurrence of wrinkles.

Example 9
The protective film (A) is an antiglare hard coat film based on a norbornene-based film, the protective film (B) is a norbornene-based film, and has a slow axis in the width direction. A polarizing plate, which is a retardation film, was prepared.

<Preparation of the protective film _{A 5>}
One surface of the long protective film A ₂ (norbornene-based film) produced in Example 2 above is subjected to corona treatment, and the hard coat layer coating liquid A-1 is a gravure pattern having 135 lines / inch and a depth of 60 μm. Using a micro gravure roll having a diameter of 50 mm and a doctor blade, the coating was carried out under conditions of a conveyance speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further under a nitrogen purge, an air-cooled metal halide lamp of 160 W / cm (eye graphics) The coated layer was cured by irradiating with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² , and wound to prepare a long protective film A ₅ .

<Production of polarizing plate _{P 9>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. The surface not laminated a hard coat layer of the protective film A ₅ prepared above was corona treated, with continuously bonded with a polyvinyl alcohol adhesive to one surface of the polarizing film, on the other surface, the protective film B ₂ was corona treated surface, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P ₉ long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, and the slow axis of the protective film B ₂ and the absorption axis of the polarizing film is the angle was 90 °.

The polarizer P ₉ produced was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _9, after two protective film laminating, curling of the polarizing plate P ₉ between the up winding is small, there was no occurrence of wrinkles.

(Example 10)
The protective film (A) is an antiglare hard coat film based on a PET film, the protective film (B) is a polycarbonate film, and has a uniaxial position having a slow axis in the width direction. A polarizing plate as a phase difference film was prepared.

<Lamination of undercoat layer SS3>
The surface where the undercoat layer (SS1) and the undercoat layer (SS2) of the protective film A3 are not laminated (the surface serving as the adhesive interface with the light scattering layer) is subjected to corona discharge treatment immediately before coating, and the following coating solution Was applied so that the dry film thickness was 90 nm, and an undercoat layer (SS3) was laminated.

[Undercoat layer SS3 coating solution composition]
・ Styrene butadiene latex (solid content 43%) 300g
・ 2,4-Dichloro-6hydroxy-s-triazine sodium salt (8%) 49 g
・ Distilled water 1,600g

<Preparation of the protective film _{A 6>}
The protective film A ₃ prepared in the above, the film obtained by laminating a primer layer SS3 unwound in roll form directly on the surface that is coated with a subbing layer SS3, the number of the hard coat layer coating liquid A-1 line 135 lines / Using a micro gravure roll with a diameter of 50 mm having a gravure pattern of inch and depth of 60 μm, and a doctor blade, the coating was performed at a conveyance speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further 160 W / cm under a nitrogen purge. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.), the coating layer is cured by irradiating with an ultraviolet ray having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² , and wound to produce a protective film A ₆ did.

<Production of polarizing plate _{P 10>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. A surface formed by laminating a primer layer SS3 protective film A ₆ prepared above, together with the bonded to the one surface with a polyvinyl alcohol-based adhesive continuously in the polarizing film on the other surface, the surface was corona-treated the protective film B _2, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P ₁₀ long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and, and the slow axis of the protective film B ₂ and the absorption axis of the polarizing film is the angle was 90 °.

The polarizer P ₁₀ produced were evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _10, after two protective film laminating, curling of the polarizing plate P ₁₀ between the up winding is small, there was no occurrence of wrinkles.

(Comparative Example 1)
A protective film (A) and a protective film (B) were cellulose acylate films, and a polarizing plate _{PR1 in} which the moisture permeability of the protective film (A) was outside the scope of the present invention was produced. A specific manufacturing method is described below. The protective film (B) is a biaxial retardation film having a slow axis in the width direction.

<Preparation of protective film (B ₄ )>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.

[Cellulose acetate solution composition]
Cellulose acetate with an acetylation degree of 60.9% (polymerization degree 300, Mn / Mw = 1.5) 100 parts by mass Triphenyl phosphate (plasticizer) 7.8 parts by mass Biphenyldiphenyl phosphate (plasticizer) 9 parts by mass / methylene chloride (first solvent) 300 parts by mass / methanol (second solvent) 54 parts by mass
・ 11 parts by mass of 1-butanol (third solvent)

  In another mixing tank, 16 parts by mass of the retardation increasing agent represented by the following general formula (1), 8 parts by mass of the retardation increasing agent represented by the following general formula (2), and silicon dioxide fine particles (average particle size: 0.00). 1 μm) 0.28 parts by mass, 80 parts by mass of methylene chloride, and 20 parts by mass of methanol were added and stirred while heating to prepare a retardation increasing agent solution (and a fine particle dispersion). The dope was prepared by mixing 45 parts by mass of the retardation increasing agent solution with 474 parts by mass of the cellulose acetate solution and stirring sufficiently.

The obtained dope was cast using a casting machine having a band having a width of 2 m and a length of 65 m. A film having a residual solvent amount of 15% by mass was stretched laterally at a stretching ratio of 20% using a tenter under the conditions of 130 ° C., held at 50 ° C. for 30 seconds with the stretched width, and then the clip was removed. Thus, a cellulose acetate film was produced. Residual solvent amount at the time of stretching terminated is 5 wt%, and further dried to a residual solvent content was prepared protective film B ₄ is a cellulose acetate film as less than 0.1 wt%. In addition, Tg of the used cellulose acylate is 140 degreeC.
The resulting width of the protective film _{B 4} is 1,340Mm, thickness was 88 .mu.m. The in-plane retardation (Re) was 60 nm and the thickness direction retardation (Rth) was 190 nm.

<Production of polarizing plate _{P R1>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. A commercially available cellulose sylate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., thickness 80 μm) was saponified and continuously bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive, on the other side, the protective film B ₄ having a surface saponified, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P _R1 long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and the slow axis of the protective and the absorption axis of the polarizing film Film B ₄ are the angle was 90 °.

The produced polarizing plate _PR1 was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _R1, after two protective film laminating, curling of the polarizing plate P _R1 between up winding is small, there was no occurrence of wrinkles.

(Comparative Example 2)
The protective film (A) is a cellulose acylate film, the moisture permeability is outside the scope of the present invention, the protective film (B) is a polycarbonate film, and the difference in hygroscopic expansion coefficient is outside the scope of the present invention. A polarizing plate _PR2 was produced. A specific manufacturing method is described below. Note that when the polarizing plate _PR2 was produced, the polarizing plate was strongly curled and wrinkled.

<Production of polarizing plate _{P R2>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film. A commercially available cellulose sylate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., thickness 80 μm) was saponified and continuously bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive, on the other side, the protective film B ₁ was corona treated surface, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P _R2 long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and the slow axis of the absorption axis of the polarizing film and the polymer film B ₁ represents the angle was 90 °.

The produced polarizing plate _PR2 was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _R2, after two protective film laminating, curling of the polarizing plate P _R2 between up winding is large, wrinkles occurred.

(Comparative Example 3)
In Comparative Example 2, a polarizing plate _PR3 was produced in the same manner as in Comparative Example 2, except that a longitudinally stretched polycarbonate film was used instead of the horizontally stretched polycarbonate film as the protective film (B). A specific manufacturing method is described below.

<Preparation of the protective film _{B 5>}
A polycarbonate copolymer obtained by copolymerizing the monomer [A] represented by the general formula (A) and the monomer [B] represented by the general formula (B) at a ratio of 33:67 (mol%) was used.
This polycarbonate copolymer was dissolved in methylene chloride to prepare an 18% by mass dope solution.
A cast film was prepared from this dope solution and longitudinally stretched 1.8 times at 235 ° C., and then the edge was cut to obtain a roll-shaped protective film B ₅ having a width of 1,340 mm. The rolled protective film _{B 5} is a thickness of 73μm, has a slow axis in the longitudinal direction, Re = 138 nm, was Rth = 80 nm.

<Production of Polarizing Plate _PR3 >
In the preparation of the polarizing plate P _R2 of Comparative Example 2, except for changing the protective film B ₁ to the protective film B _5, the procedure of Comparative Example 2, a polarizing plate was prepared P _R3 long. In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction and the slow axis and the angle between the absorption axis of the polarizing film and the polymer film B ₅ was 0 °.

The produced polarizing plate _PR3 was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _R3, after two protective film laminating, curling of the polarizing plate P _R3 between up winding is large, wrinkles occurred.

(Comparative Example 4)
Protective Film (A) is a norbornene-based film, a protective film (B) is the difference is hygroscopic expansion coefficient cellulose acylate film, a polarizing plate was prepared P _R4 exceeding RH 10 ppm /%.

<Production of Polarizing Plate _PR4 >
In the polarizing plate P _R1 produced in Comparative Example 1, the protective film (A), except that the polymer film A ₂ was subjected to corona treatment, in the same manner as in Comparative Example 1 to prepare a polarizing plate P _R4 .

The produced polarizing plate _PR4 was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _R4, after two protective film laminating, curling of the polarizing plate P _R4 between up winding is large, wrinkles occurred.

(Comparative Example 5)
The protective film (A) is a cellulose acylate film, the protective film (B) is a polycarbonate film, and the protective film (B) is a retardation film having substantially only a thickness direction, and is hygroscopically expanded. A polarizing plate _{PR5 in} which the difference in coefficient and the moisture permeability of the protective film (A) exceeded 200 g / m ² · day was produced.

<Preparation of polarizing plate _PR5 >
For the polarizing plate P ₅ produced in Example 5 above, the protective film A ₁ was changed to a commercially available cellulose acylate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., thickness 80 μm) that was saponified. In the same manner as in Example 5, a polarizing plate _PR5 was produced.

The produced polarizing plate _PR5 was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _R5, after two protective film laminating, curling of the polarizing plate P _R5 between up winding is large, wrinkles occurred.

(Comparative Example 6)
The protective film (A) is an antiglare hard coat film based on a cellulose acylate film, the protective film (B) is a polycarbonate film, and the protective film (B) is delayed in the width direction. A polarizing plate PR06, which is a uniaxial retardation film having a phase axis, in which the difference in hygroscopic expansion coefficient and the moisture permeability of the protective film (A) exceed 200 g / m ² · day, was produced.

<Preparation of the protective film _{A 7>}
A commercially available cellulose acylate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., thickness 80 μm) is unwound in a roll form and directly coated with the above-mentioned hard coat layer coating solution A-1 at 135 lines / inch, depth Using a microgravure roll with a diameter of 50 mm and a doctor blade having a gravure pattern of 60 μm, coating was performed at a conveyance speed of 10 m / min, drying at 60 ° C. for 150 seconds, and then air-cooled metal halide of 160 W / cm under a nitrogen purge. Using a lamp (manufactured by Eye Graphics Co., Ltd.), the coating layer was cured by being irradiated with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² , and wound up.

<Production of Polarizing Plate _PR6 >
In the preparation of the polarizing plate P _R2 of Comparative Example 2, a protective film (A), except for changing the protective film A ₇ subjected to saponification treatment, in the same manner as in Comparative Example 2, to prepare a P _R6. Incidentally, the lamination surface of the polarizing film of the protective film A ₇ is a surface not laminated a hard coat layer.

The produced polarizing plate _PR6 was evaluated in the same manner as in Example 1. The results are shown in Table 2. Incidentally, when manufacturing the polarizer P _R6, after two protective film laminating, curling of the polarizing plate P _R6 between up winding is large, wrinkles occurred.

(Comparative Example 7)
In the comparative example 2, the polarizing plate preparation was changed from a roll-to-roll of a long roll-shaped film to a single sheet to prepare a polarizing plate _PR7 . A specific manufacturing method is described below.

<Preparation of polarizing plate _PR7 >
A roll-like polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the conveying direction, and a 100 cm × 100 cm polarizing film was cut out after drying.
Next, a commercially available cellulose sylate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., thickness 80 μm) was saponified and cut into 100 cm × 100 cm.
Further, the protective film _{B 1} was corona treated surface was cut into 100 cm × 100 cm.
The cellulose acylate film cut out above is bonded to one surface of the polarizing film cut out above using a polyvinyl alcohol adhesive, and the protective film B ₁ cut out above is attached to the other surface, Bonding was performed using a polyvinyl alcohol-based adhesive to produce a single-wafer polarizing plate _PR7 . In this case, the absorption axis of the polarizing film is parallel to the longitudinal direction, and the slow axis of the absorption axis of the polarizing film and the polymer film B ₁ represents the angle was 90 °.
The above operation was repeated 200 times to produce 200 single-wafer polarizing plates _PR7 having a size of 100 cm × 100 cm.

The produced polarizing plate _PR7 was evaluated in the same manner as in Example 1. The results are shown in Table 2. In addition, although the curl of the 200 polarizing plates _PR7 produced above was large, wrinkles were not generated.

Here, each characteristic of the protective film (A) and the protective film (B) used in the present invention (moisture permeability at 60 ° C. and 95% RH (g / m ² · day), hygroscopic expansion coefficient (ppm /% RH)) Table 1 shows Re (nm) and Rth (nm) of the base material, Re (nm) and Rth (nm) of the optically anisotropic layer, and pencil hardness).
In addition, the pencil hardness of the protective film A in Table 1 and the pencil hardness on the protective film A side of the polarizing plate in Table 2 were measured using the following evaluation methods.

[Pencil hardness evaluation]
As an index of scratch resistance, pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the light diffusive film at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, the following evaluation criteria were used at a load of 4.9 N using a 2H-5H test pencil specified in JIS S 6006. The highest hardness that gave an OK was taken as the evaluation value.

[Evaluation criteria]
OK: No scratch in evaluation of n = 5 to 1 wound NG: 3 or more scratches in evaluation of n = 5

From the results in Table 2, the following is clear.
By controlling the moisture permeability of the protective film (A), which is a protective film on one side of the polarizing plate, to 200 g / m ² · day or less, the glass plate caused by the expansion and contraction of the polarizing film accompanying the change in humidity of the polarizing plate storage environment Distortion can be reduced.
Moreover, the curl caused by the change in the storage humidity of the polarizing plate can be controlled by controlling the difference between the hygroscopic expansion coefficients of the protective film (A) and the protective film (B), which are protective films on both sides of the polarizing plate, to 10 ppm /% RH or less. Generation can be reduced.
Furthermore, by controlling the difference in hygroscopic expansion coefficient between the protective film (A) and the protective film (B), which are protective films on both sides of the polarizing plate, to 10 ppm /% RH or less, After the two protective films are bonded to the polarizing plate, wrinkles can be prevented from occurring until winding.

Moreover, it was recognized that the polarizing plate which employ | adopted the longitudinally-stretched protective film (B) had more wrinkles at the time of conveyance than the polarizing plate which employ | adopted the laterally-stretched protective film (B).
Moreover, compared with the case where a protective film (B) is a transversely stretched film, the wrinkles are more often generated in the case of a longitudinally stretched film because the thermal expansion coefficient in the stretching direction is smaller than that in the unstretched direction. Estimated.

(Example 7)
A protective film having a small retardation is provided in the same manner as in Example 1 except that the protective film (B) of the polarizing plate P ₁ produced in Example 1 is changed from a retardation film to a film with little retardation. to prepare a polarizing plate _{P 7.} Specifically, as a protective film (B), using a polymer film A ₁ used in Example 1.
The polarizer P ₇ produced was evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Example 8)
A protective film of a polarizing plate P ₂ prepared in the above Example 2 (B), except that instead of the small film of retardation from the retardation film, in the same manner as in Example 2, has a small protective film of the phase difference to prepare a polarizing plate _{P 8.} Specifically, as a protective film (B), using a polymer film A ₂ used in Example 2 above.
The polarizer P ₈ prepared was evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Comparative Example 6)
A protective film of a polarizing plate P _R1 produced in Comparative Example 1 (B), except that instead of the small film of retardation from the retardation film, in the same manner as in Comparative Example 1, has a small protective film of the phase difference A polarizing plate _PR6 was produced. Specifically, as the protective film (B), a commercially available low retardation TAC film (Z-TAC manufactured by Fuji Photo Film Co., Ltd.) was used.
The produced polarizing plate _PR6 was evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Comparative Example 7)
Protective film (B) of the polarizing plate P _R2 produced in Comparative Example 2, except that instead of the small film of retardation from the retardation film, in the same manner as in Comparative Example 2 has a small protective film of the phase difference A polarizing plate _PR7 was produced. Specifically, as the protective film (B), a commercially available low retardation TAC film (Z-TAC manufactured by Fuji Photo Film Co., Ltd.) was used.
The produced polarizing plate _PR7 was evaluated in the same manner as in Example 1. The results are shown in Table 3.

From the results in Table 3, the following is clear.
Even when a polymer film having a small retardation is used for the protective film (B), the moisture permeability of the protective film (A), which is a protective film on one side of the polarizing plate, is controlled to be 200 g / m ² · day or less. The distortion of the glass plate resulting from the expansion and contraction of the polarizing film accompanying the change in humidity in the plate storage environment can be reduced.
Moreover, by controlling the difference between the hygroscopic expansion coefficient of the protective film (A), which is the protective film on both sides of the polarizing plate, and the hygroscopic expansion coefficient of the protective film (B), to 10 ppm /% RH or less, The occurrence of curling due to changes in storage humidity can be reduced.
Furthermore, the difference between the hygroscopic expansion coefficient of the protective film (A), which is the protective film on both sides of the polarizing plate, and the hygroscopic expansion coefficient of the protective film (B) is controlled to 10 ppm /% RH or less, thereby reducing the difference between the two. It is possible to prevent the generation of wrinkles until the sheets are wound up after the protective films are bonded.

Example 9
(Preparation of Polarizing Plate P ₉ having an optically anisotropic layer)
<Synthesis of cyclic olefin polymer>
100 parts by mass of purified toluene and 100 parts by mass of norbornene carboxylic acid methyl ester were charged into a reaction kettle. Next, ethyl hexanoate-Ni dissolved in toluene 25 mmol% (based on monomer mass), tri (pentafluorophenyl) boron 0.225 mol% (based on monomer mass), and triethylaluminum 0.25 mol% dissolved in toluene (based on monomer) Mass) was charged into the reaction kettle. The reaction was allowed to proceed for 18 hours at room temperature with stirring. After completion of the reaction, the reaction mixture was put into excess ethanol to produce a polymer precipitate. The precipitate was purified, and the obtained polymer (J1) was dried at 65 ° C. for 24 hours by vacuum drying.

<Formation of polymer film b ₆ >
The following composition was put into a mixing tank and stirred to dissolve each component, and then filtered through a filter paper having an average pore size of 34 μm and a sintered metal filter having an average pore size of 10 μm.

[Cyclic polyolefin solution D1 composition]
-Cyclic polyolefin (J1) 150 parts by mass-Dichloromethane 414 parts by mass
・ Methanol 36 parts by mass

  Next, the following composition containing the cyclic polyolefin solution prepared by the above method was charged into a disperser to prepare a mat agent dispersion.

[Matting agent dispersion M1 composition]
-Silica particles having an average particle size of 16 nm (aerosil R972 Nippon Aerosil Co., Ltd.) 2 parts by mass-81 parts by mass of dichloromethane-7 parts by mass of methanol
・ 10 parts by mass of cyclic polyolefin solution (D1)

100 parts by mass of the cyclic polyolefin solution D1 and 1.35 parts of the matting agent dispersion M1 were mixed to prepare a dope for film formation.
The above dope was cast at a width of 1,400 mm by a band casting machine. The film peeled off from the band with a residual solvent amount of about 25% by mass was stretched by 10% in the width direction by applying hot air at 140 ° C. using a tenter while keeping the film from wrinkling.
Then, it shifted to tenter conveyance and roll conveyance, and also it dried at 120 to 140 degreeC, and wound up.
The produced film was passed through a dielectric heating roll having a temperature of 60 ° C., and the film surface temperature was raised to 40 ° C. Then, an alkaline solution having the following composition was applied by a bar coater to 14 mL / m ² and heated to 110 ° C. After being kept for 10 seconds under the steam type far infrared heater (manufactured by Noritake Co., Ltd.), 3 mL / m ^{2 of} pure water was similarly applied using a bar coater. The film temperature at this time was 40 degreeC.
Next, washing with a fountain coater and draining with an air knife were repeated three times, and then the sample was retained in a drying zone at 70 ° C. for 2 seconds and dried.

[Alkaline solution composition]
-4.7 parts by weight of potassium hydroxide-15.7 parts by weight of water-64.8 parts by weight of isopropanol-14.9 parts by weight of propylene glycol
_{· C 16 H 33 O (CH} 2 CH 2 O) 10 H ( surfactant) 1.0 part by weight

The optical characteristics of the produced cyclic polyolefin film were measured using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments). Re measured at a wavelength of 590 nm was 60 nm, and Rth was 190 nm.
Moreover, the slow axis of this optically anisotropic layer was orthogonal to the longitudinal direction of the film. The film was a polymer film b _6.

<Formation of optically anisotropic layer>
The surface subjected to saponification treatment of the elongated prepared polymer film b _6, was continuously applied with a wire bar of the alignment film coating solution # 14 of the following composition. The alignment film was formed by drying with warm air of 60 ° C. for 60 seconds and further with warm air of 100 ° C. for 120 seconds.
[Composition of alignment film coating solution]
・ Modified polyvinyl alcohol represented by the following general formula (3) 10 parts by mass, water 371 parts by mass, methanol 119 parts by mass
・ Glutaraldehyde 0.5 parts by mass

A coating solution containing a rod-like liquid crystal compound having the following composition was continuously applied onto the prepared alignment film with a # 5.0 wire bar. The conveying speed of the polymer film _{b 6} was 20 m / min. The solvent was dried in a step of continuously heating from room temperature to 80 ° C., and then heated in a drying zone at 80 ° C. for 90 seconds to align the rod-like liquid crystal compound.
Subsequently, the temperature of the polymer film b ₆ was maintained at 60 ° C., and the alignment of the liquid crystal compound was fixed by UV irradiation to form an optically anisotropic layer.
Subsequently, the film prepared in a 1.5 mol / L sodium hydroxide aqueous solution at 55 ° C. was immersed for 2 minutes, and then immersed in water to sufficiently wash away sodium hydroxide.
Then, after being immersed for 1 minute in 5 mmol / L sulfuric acid aqueous solution of 35 degreeC, it was immersed in water and the dilute sulfuric acid aqueous solution was fully washed away. Finally, the sample was thoroughly dried at 120 ° C. Thus, to produce a protective film B ₆ which optically anisotropic layer are laminated.

[Composition of coating liquid (S1) containing rod-like liquid crystal compound]
-100 parts by mass of rod-shaped liquid crystalline compound (I) represented by the following general formula (4)-Photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) 3 parts by mass-Sensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.) 1 part by mass / fluorine polymer represented by the following general formula (5) 0.4 part by mass / pyridinium salt represented by the following general formula (6) 1 part by mass
・ 172 parts by mass of methyl ethyl ketone

Detached from the protective film B ₆ produced only the optically anisotropic layer comprising rod-like liquid crystal compound, an automatic double refractometer to measure the optical characteristics using (KOBRA-21ADH, Oji Scientific Instruments Co., Ltd.) . Re of only the optically anisotropic layer measured at a wavelength of 590 nm was 0 nm, and Rth was −260 nm. It was also confirmed that an optically anisotropic layer in which rod-like liquid crystal molecules were aligned substantially perpendicular to the film surface was formed.

<Fabrication of the polarizer _{P 8>}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm continuously dyed in an aqueous iodine solution was stretched 5 times in the transport direction and dried to obtain a long polarizing film.
One side of this polarizing film was subjected to corona treatment on the surface on which the optically anisotropic layer of the produced protective film B ₆ was not formed (that is, the back surface of the polymer film b ₆ ) and on the other surface. the protecting film a _1, continuously laminated with a polyvinyl alcohol adhesive to prepare a polarizing plate P ₈ long. At this time, the absorption axis of the polarizing film was parallel to the longitudinal direction, and the angle formed by the absorption axis of the polarizing film and the slow axis of the optically anisotropic layer of the polymer film b ₆ was 90 °. .
The polarizer P ₈ prepared was evaluated in the same manner as in Example 1. The results are shown in Table 4.

(Comparative Example 8)
<Preparation of the protective film _{B 7>}
To the protective film B ₆ prepared above to prepare a protective film B ₇ was changed to a commercially available low retardation TAC film subjected to saponification treatment substrate on one side (Z-TAC manufactured by Fuji Photo Film Co., Ltd.) .

<Production of Polarizing Plate _PR8 >
The protective film, commercially available cellulose acylate film (FUJITAC TD80UF, manufactured by Fuji Photo Film Co., Ltd., 80 [mu] m thickness), and as a protective film _{B 7,} to produce a polarizing plate _{P R8} having an optically anisotropic layer.
The produced polarizing plate _PR8 was evaluated in the same manner as in Example 1. The results are shown in Table 4.

(Comparative Example 9)
<Production of Polarizing Plate _PR9 >
The protective film A ₁ of the polarizing plate P ₈ prepared in Example 8, except that instead of the commercially available cellulose acetate film (FUJITAC TD80UF, manufactured by Fuji Photo Film Co., Ltd.) in the same manner as in Example 8, optically anisotropic A polarizing plate _PR9 having an isotropic layer was produced.
The produced polarizing plate _PR9 was evaluated in the same manner as in Example 1. The results are shown in Table 4.

From the results of Table 4, the following is clear.
Even when the protective film (B) has an optically anisotropic layer, the polarizing film is preserved by controlling the moisture permeability of the protective film (A), which is a protective film on one side of the polarizing plate, to 200 g / m ² · day or less. It is possible to reduce the distortion of the glass plate due to the expansion and contraction of the polarizing film accompanying the environmental humidity change.
Moreover, the preservation | save of a polarizing plate is controlled by controlling the difference of the hygroscopic expansion coefficient of the protective film (A) which is a protective film of both surfaces of a polarizing plate, and the hygroscopic expansion coefficient of a protective film (B) to 10 ppm /% RH or less. The occurrence of curling due to humidity changes can be reduced.
Furthermore, by controlling the difference between the hygroscopic expansion coefficient of the protective film (A), which is the protective film on both sides of the polarizing plate, and the hygroscopic expansion coefficient of the protective film (B) to 10 ppm /% RH or less, After bonding two protective films, it is possible to prevent wrinkles from occurring until winding.

(Example 10)
<Production of liquid crystal display device>
<< Production of VA Mode Liquid Crystal Display Device >>
The polarizing plates on the front and back of the VA mode 37-inch size liquid crystal TV (LC-37GE2, manufactured by Sharp Corporation) and the retardation plate were peeled off, and the polarizing plates produced above were combined into the 37-inch size according to the combinations shown in Table 5. Punched and pasted on a liquid crystal cell. At this time, the absorption axis of the polarizing plate on the viewing side is in the horizontal direction of the panel, the absorption axis of the polarizing plate on the backlight side is in the vertical direction of the panel, and the polymer film (b) is arranged on the liquid crystal cell side. to produce a display device _{L 10.}

The liquid crystal display device L ₁₀ produced were evaluated according to the following method. The results are shown in Table 5.

(1) Light leakage (front)
A liquid crystal display device is placed in a dark room without a polarizing plate, and a luminance meter (spectral radiance meter CS-1000: manufactured by Minolta Co., Ltd.) installed at a distance of 1 m in the normal direction has a luminance of 1 Was measured.
Next, each liquid crystal display device to which a polarizing plate was bonded was placed, and the luminance 2 was measured in the same manner as described above.

(2) Leakage light (oblique)
Place the liquid crystal display device in the darkroom with no polarizing plate attached, with the orientation of 45 degrees to the left and the direction of 60 degrees from the normal direction of the liquid crystal cell, 1 m away from the rubbing direction of the liquid crystal cell. The luminance 1 was measured with a luminance meter (spectral radiance meter CS-1000: manufactured by Minolta Co., Ltd.) installed there.
Next, each liquid crystal display device to which the polarizing plate was bonded was placed, the luminance 2 was measured in the same manner as described above, and the value expressed as a percentage with respect to the luminance 1 was regarded as obliquely leaked light.

(3) Evaluation of light leakage after high-temperature and low-humidity treatment The liquid crystal display device produced above was left in an environment of 60 ° C. and 90% RH for 50 hours, then left in an environment of 25 ° C. and 60% RH for 2 hours, and then liquid crystal The display device was displayed in black, and light leakage from the front to the periphery was visually evaluated according to the following evaluation criteria.

[Evaluation criteria]
A: No light leakage was observed.
Δ: Slight light leakage was observed.
X: Light leakage was clearly observed.

(Comparative Example 10)
<Production of liquid crystal display device>
<< Production of VA Mode Liquid Crystal Display Device >>
The polarizing plates on the front and back of the VA mode 37-inch size liquid crystal TV (LC-37GE2, manufactured by Sharp Corporation) and the retardation plate were peeled off, and the polarizing plates produced above were combined into the 37-inch size according to the combinations shown in Table 5. Punched and pasted on a liquid crystal cell. At this time, the absorption axis of the polarizing plate on the viewing side is in the horizontal direction of the panel, the absorption axis of the polarizing plate on the backlight side is in the vertical direction of the panel, and the polymer film (b) is arranged on the liquid crystal cell side. A display device _LR10 was produced.

The produced liquid crystal display device _LR10 was evaluated in the same manner as in Example 10. The results are shown in Table 5.

(Comparative Example 11)
<Production of liquid crystal display device>
<< Production of VA Mode Liquid Crystal Display Device >>
The polarizing plates on the front and back of the VA mode 37-inch size liquid crystal TV (LC-37GE2, manufactured by Sharp Corporation) and the retardation plate were peeled off, and the polarizing plates produced above were combined into the 37-inch size according to the combinations shown in Table 5. Punched and pasted on a liquid crystal cell. At this time, the absorption axis of the polarizing plate on the viewing side is in the horizontal direction of the panel, the absorption axis of the polarizing plate on the backlight side is in the vertical direction of the panel, and the polymer film (b) is arranged on the liquid crystal cell side. A display device _LR11 was produced.

The produced liquid crystal display device _LR11 was evaluated in the same manner as in Example 10. The results are shown in Table 5.

From the results in Table 5, the following is clear.
By using the polarizing plate of the present invention on both surfaces of the liquid crystal cell, there was little light leakage from an oblique direction, and light leakage after high temperature and low temperature treatment did not occur.

(Example 11)
<Production of liquid crystal display device>
<< Preparation of IPS Mode Liquid Crystal Display >>
The liquid crystal cell was taken out from the IPS mode liquid crystal television TH-32LX500 (manufactured by Matsushita Electric Industrial Co., Ltd.), and the polarizing plate and the optical film attached to the viewer side and the backlight side were peeled off. In this liquid crystal cell, when no voltage was applied and during black display, the liquid crystal molecules were aligned substantially in parallel between the glass substrates, and the slow axis direction was horizontal to the screen.

The produced polarizing plate P ₈ and polarizing plate P ₇ were bonded to the upper and lower glass substrates of the parallel alignment cell using an adhesive. At this time, the polarizing plate P ₇ is disposed as the polarizing plate on the backlight side, the polarizing plate P ₈ is disposed as the polarizing plate on the viewing side, and the optical anisotropic layer included in the polarizing plate P ₈ is on the viewing side. Bonding was performed so that the polymer film A ₂ contained in the polarizing plate P ₇ was in contact with the glass substrate on the backlight side so as to be in contact with the glass substrate.
Further, the slow axis and the absorption axis and the liquid crystal cell of the polarizing plate P ₈ is set to be parallel, the absorption axis of the polarizer P ₈ and the polarizing plate P ₇ was arranged so as to be orthogonal.
The thus liquid crystal cell bonding the polarizing plate, again, built in LCD TV TH-32LX500, to produce a liquid crystal display device _{L 11.}
A liquid crystal display device L ₁₁ produced were evaluated in the same manner as the VA liquid crystal display device of Example 10. The results are shown in Table 6.

(Comparative Examples 12-13)
<Production of liquid crystal display device>
<< Preparation of IPS Mode Liquid Crystal Display >>
In Example 11, a liquid crystal display device L _R12 of Comparative Example 12 and a liquid crystal display device L _R13 of Comparative Example 13 were produced in the same manner as Example 11 except that the polarizing plates were installed in the combinations shown in Table 6. .
The manufactured liquid crystal display device L _R12 and liquid crystal display device L _R13 were evaluated in the same manner as the VA liquid crystal display device of Example 10. The results are shown in Table 6.

From the results of Table 6, the following is clear.
By using the polarizing plate of the present invention on both surfaces of the liquid crystal cell, there was little light leakage from an oblique direction, and light leakage after high temperature and low temperature treatment did not occur.

The polarizing plate of the present invention is highly productive, hardly curls against changes in temperature and humidity, and has high moisture resistance, so that high contrast and color shift depending on the viewing angle direction during black display can be improved. It can be suitably used for a liquid crystal display device in which the viewing angle contrast is remarkably improved.
Since the liquid crystal display device of the present invention has less light leakage with respect to changes in temperature and humidity, it can be suitably used for mobile phones, personal computer monitors, televisions, liquid crystal projectors, and the like.

Claims (14)

A polarizing film, a protective film (A) based on the polymer film (a), which is laminated on one surface of the polarizing film, and a polymer film (b) which is laminated on the other surface of the polarizing film. A protective film (B) as a material,
The moisture permeability at 60 ° C. and 95% RH of the protective film (A) is 200 g / m ² · day or less,
The difference between the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) is 10 ppm /% RH or less.   The polarizing plate according to claim 1, wherein the difference between the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) is 5 ppm /% RH or less.   The polarizing plate according to claim 1, wherein both the hygroscopic expansion coefficient of the protective film (A) and the hygroscopic expansion coefficient of the protective film (B) are 50 ppm /% RH or less.   The polarizing plate according to claim 1, wherein the polarizing plate has a long roll shape.   5. The polarizing plate according to claim 1, wherein the in-plane retardation Re of the polymer film (b) is 15 to 300 nm and / or the retardation Rth in the thickness direction is 60 to 300 nm.   The polymer film (b) has an in-plane retardation Re of 15 to 300 nm, and the slow axis of the polymer film (b) and the absorption axis of the polarizing plate are substantially perpendicular to each other. The polarizing plate of crab.   The functional layer is formed on the polymer film (b), the in-plane retardation Re of the functional layer is 15 to 300 nm, and / or the thickness direction retardation Rth is 60 to 300 nm. The polarizing plate in any one.   The polarizing plate according to claim 7, wherein the functional layer is an optically anisotropic layer formed from a liquid crystalline compound.   The polarizing plate according to claim 1, wherein a hard coat layer is formed on the polymer film (a).   The polarizing plate according to claim 1, wherein at least one of the polymer film (a) and the polymer film (b) is a polycarbonate film.   The polarizing plate according to any one of claims 1 to 9, wherein at least one of the polymer film (a) and the polymer film (b) is a norbornene-based film.   A liquid crystal display device comprising: the polarizing plate according to claim 1; and a liquid crystal cell, wherein a protective film (B) side of the polarizing plate is bonded to the liquid crystal cell. .   A pair of polarizing plates whose absorption axes are orthogonal to each other; a pair of substrates disposed between the polarizing plates; and a liquid crystal layer composed of liquid crystalline molecules sandwiched between the substrates. The liquid crystal display device according to claim 12, wherein the liquid crystal display device is aligned in a direction substantially perpendicular to the substrate in a non-driven state in which no voltage is applied. A pair of polarizing plates whose absorption axes are orthogonal to each other; a pair of substrates disposed between the polarizing plates; and a liquid crystal layer composed of liquid crystalline molecules sandwiched between the substrates. The liquid crystal display device according to claim 12, wherein the liquid crystal display device is aligned in a substantially horizontal direction with respect to the substrate in a non-driven state in which no voltage is applied.