JP2005208606A - Polarizing plate and liquid crystal display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate having satisfactory scratch resistance and an antireflection function particularly when the film is made thinner, although the plate is provided with an excellent optical compensation function, dispensing with the increase in the number of constitutional films. <P>SOLUTION: The polarizing plate having the optical compensation function and the antireflection function is constituted of the antireflection film, where at least one sheet of films having the polarizing function on one side of the polarizing film is constituted of only one sheet of cellulose acetate film containing aromatic compound having two aromatic rings of 0.01 to 20% mass to cellulose acylate 100% mass, and having an Re retardation value of 20 to 70nm and an Rth retardation value of 70 to 400nm, and at least one functional film on the other side is provided with a glare shielding hard-coated layer, a hard-coated layer not having the glare shielding performance, at least either of an middle refractive index layer or a high refractive index layer and a low refractive index layer on a transparent supporting body. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a polarizing plate having a functional film having a performance as an optical compensation sheet composed of only one cellulose acylate film on one side of the polarizing film and an antireflection film on the other side of the polarizing film. More specifically, the present invention relates to a polarizing plate and a liquid crystal display device that have both an optical compensation function and an antireflection function.

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, and enabling miniaturization and thinning. For such a liquid crystal display device, various modes have been proposed depending on the alignment state of the liquid crystal in the liquid crystal cell. Conventionally, the liquid crystal is in an alignment state in which the liquid crystal is twisted by about 90 ° from the lower substrate to the upper substrate of the cell. Mode is mainstream.
In general, a liquid crystal display device includes a liquid crystal cell, an optical compensation sheet, and a polarizing plate. Optical compensation sheets are used to reduce image coloration and widen the viewing angle, and stretched birefringent films and transparent films coated with liquid crystals are used. For example, Patent Document 1 discloses a technique for applying a discotic liquid crystal on a triacetyl cellulose film, aligning and fixing the optical compensation sheet to a TN mode liquid crystal cell, and widening the viewing angle. However, a liquid crystal display device for television that is expected to be viewed from various angles on a large screen has a strict requirement for viewing angle dependency, and even if the above-described method is used, the requirement cannot be completely met. 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 it has a high contrast and a relatively high manufacturing yield.

Cellulose acylate film has higher optical isotropy (lower retardation value) than other polymer films, so it is usually used for applications requiring optical isotropy, such as polarizing plates. It has been.
On the other hand, optical anisotropy (high retardation value) is required for the optical compensation sheet (retardation film) of the liquid crystal display device. In such a case, a synthetic polymer film having a high retardation value such as a polycarbonate film or a polysulfone film is generally used for the optical compensation sheet.
Patent Document 2 discloses a cellulose acetate film having a high retardation value that can be used for applications that require optical anisotropy by overturning conventional general principles. In this patent document, in order to achieve a high retardation value with cellulose triacetate, a compound having at least two aromatic rings, particularly a compound having a 1,3,5-triazine ring, is added and subjected to stretching treatment. Cellulose triacetate is generally a polymer material that is difficult to stretch, and it is known that it is difficult to increase the birefringence, but the birefringence is increased by simultaneously orienting the additive in the stretching process. This makes it possible to achieve a high retardation value. Since this film can also serve as a protective film for the polarizing plate, there is an advantage that an inexpensive and thin liquid crystal display device can be provided.

In recent years, it has become essential to reduce the thickness of a liquid crystal cell in order to reduce the weight of the liquid crystal display device and reduce the manufacturing cost. Therefore, the optical compensation sheet is required to have a higher Re retardation value and a lower Rth retardation value. However, the method of Patent Document 2 has a problem that when the above-mentioned Re retardation value and Rth retardation value are individually specified, they cannot be compatible.
Patent Document 3 discloses that the Rth value is controlled, but the Re value and the Rth value cannot be made compatible.
In order to solve the above problems, an optical compensation sheet made of a cellulose acetate film as in Patent Document 4 has been newly proposed. However, the polarizing plate made of the optical compensation sheet of Patent Document 4 has a problem as described later that the scratches on the outermost layer are easily noticeable.

That is, such an optical compensation sheet is usually provided on one side of the polarizing film, and a transparent protective film is provided on the other side of the polarizing film, which is a normal configuration of the polarizing plate. However, when the outermost transparent protective film is only a normal cellulose acylate film that does not have an anti-reflection function, contrast deterioration due to reflection of external light, obstruction of viewing due to image reflection, and poor scratch resistance are conspicuous. There were problems such as easy.
Further, in general display devices such as a cathode ray tube display (CRT), a liquid crystal display (LCD), a plasma display (PDP), and an electroluminescence display (ELD), the reflectance is reduced by using the principle of optical interference. It is known to arrange a simple antireflection film on the outermost surface of the display.
The polarizing plate having the optical compensation sheet described above is effective for reducing the thickness of the liquid crystal cell. When an external force is applied and the membrane is damaged, the deformation is sharp and conspicuous.
Japanese Patent No. 2587398 European Patent 0911656A2 JP 2001-116926 A JP 2001-249223 A

In short, a polarizing plate that achieves both an optical compensation function and an anti-reflection function and is less prone to scratches on the surface has not yet been proposed. Currently, there is a demand for the development of polarizing plates that have the same performance.
An object of the present invention is to provide a polarizing plate having a functional film composed only of a cellulose acylate film to which an optical compensation function has been imparted, in particular by providing an antireflection function without increasing the number of constituent members, and in addition to scratching the surface. It is to provide a polarizing plate with less scratches, and to provide a liquid crystal display device provided with a polarizing plate having these functions.

As a result of intensive studies to solve the above problems, the present inventors have obtained the following knowledge regarding the retardation value.
That is, the Re retardation value and the Rth retardation value are values defined by the refractive index in the triaxial direction, and the Re / Rth ratio can be controlled by an additive having a large contribution to the retardation. It has been found that the Re / Rth ratio increases as the value increases, and the Re / Rth ratio increases as the amount added increases. The slope of the Re / Rth ratio with respect to the draw ratio was determined by the additive, and it was found that the slope of the discotic compound described in Patent Document 2 is small.
Further, when the optimum Re and Rth values are realized by the tenter stretching method, it is necessary to increase the Re / Rth increase amount with respect to the stretching ratio. Specifically, it is preferable to use an additive having a structure in which the difference between nx and ny tends to increase, and as a result of investigation, it has been found that this can be achieved by using an aromatic compound having at least two aromatic rings. Among these, it has been found that a rod-like compound having at least two aromatic rings and a linear molecular structure is more preferable.
Furthermore, when the functional film with an optical compensation function described above is applied to a polarizing plate, it can be seen that a normal cellulose acylate film whose outermost layer on the opposite side does not have an antireflection function is easily scratched. It has been found that the degree of scratches can be reduced by using a specific antireflection film as the protective film.

And based on the said knowledge, it came to complete this invention.
That is, this invention achieves the said objective by each following invention.
(1) A polarizing plate in which at least one functional film is disposed on each side of the polarizing film,
At least one of the functional films on one side is composed of only one cellulose acylate film, and the cellulose acylate film is an aromatic having at least two aromatic rings with respect to 100 parts by mass of the cellulose acylate. 0.01 to 20 parts by mass of the compound, the Re retardation value defined by the following formula (I) is 20 to 70 nm, and the Rth retardation value defined by the following formula (II) is 70 to 400 nm. ,
At least one of the functional films on the other side is at least one of an antiglare hard coat layer, a hard coat layer having no antiglare property, a medium refractive index layer, or a high refractive index layer on a transparent support. A polarizing plate comprising an antireflection film having a layer and a low refractive index layer.
(I) Re = (nx−ny) × d
(II) Rth = {(nx + ny) / 2−nz} × d
Where nx is the refractive index in the slow axis direction in the film plane; ny is the refractive index in the fast axis direction in the film plane; nz is the refractive index in the thickness direction of the film; and d Is the thickness of the film. ]
(2) A polarizing plate in which at least one functional film is disposed on each side of the polarizing film,
At least one of the functional films on one side is composed of only one cellulose acylate film, and the cellulose acylate film is an aromatic having at least two aromatic rings with respect to 100 parts by mass of the cellulose acylate. 0.01 to 20 parts by mass of the compound, the Re retardation value defined by the following formula (I) is 20 to 70 nm, and the Rth retardation value defined by the following formula (II) is 70 to 400 nm. ,
That at least one of the functional films on the other side is formed of an antireflection film having at least one of an antiglare hard coat layer or a high refractive index layer and a low refractive index layer on a transparent support. A characteristic polarizing plate.
(I) Re = (nx−ny) × d
(II) Rth = {(nx + ny) / 2−nz} × d
Where nx is the refractive index in the slow axis direction in the film plane; ny is the refractive index in the fast axis direction in the film plane; nz is the refractive index in the thickness direction of the film; and d Is the thickness of the film. ]
(3) The polarizing plate according to (1) or (2), wherein the cellulose acylate film has a thickness of 40 μm or more and 70 μm or less.
(4) The polarizing plate according to any one of (1) to (3), wherein the aromatic compound is a rod-shaped compound having a linear molecular structure.
(5) The polarizing plate according to (1) to (4), wherein the cellulose acylate is cellulose acetate having an acetylation degree of 59.0 to 61.5%.
(6) The polarizing plate according to (1) to (5), wherein the cellulose acylate film is stretched at a stretching ratio of 3 to 100%.
(7) The polarizing plate according to (1) to (6), wherein the Re retardation value of the cellulose acylate film is 40 to 70 nm and the Rth retardation value is 90 to 250 nm.
(8) The polarizing plate according to any one of (6) to (7), wherein an amount of change in Re / Rth per 1% stretch ratio is 0.01 or more and 0.04 or less.
(9) The cellulose acylate film is stretched in a direction perpendicular to the longitudinal direction while being conveyed in the longitudinal direction in a state where the residual solvent amount is 2% or more and 30% or less, and the slow axis of the film is the length of the film The polarizing plate according to any one of (1) to (8), wherein the polarizing plate is in a direction orthogonal to the direction.
(10) The composition for forming at least one of a hard coat layer having no antiglare property, an antiglare hard coat layer and a low refractive index layer of the antireflection film is represented by the following general formula (1). The polarizing plate according to any one of (1) to (9), which contains an organosilane compound and / or a hydrolyzate thereof and / or a partial condensate thereof.
Formula ^{(1): (R 10)} m -Si (X) 4-m
[In the general formula (1), R ¹⁰ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. X represents a hydroxyl group, an alkoxy group, a halogen atom, or an R ² COO group, R ² represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and m represents an integer of 1 to 3. ]
(11) The low refractive index layer of the antireflection film contains at least one silica fine particle, at least one of the silica fine particles is a hollow silica fine particle, and the refractive index of the fine particle is 1.17 to 1. 40. The polarizing plate according to any one of (1) to (10), wherein the polarizing plate is.
(12) The antiglare hard coat layer of the antireflection film contains matting agent particles and a binder, and a difference in refractive index between the matting agent particles and the binder is 0.03 or more and 0.2 or less. The polarizing plate according to any one of (1) to (11).
(13) The polarizing plate according to (1) to (12), wherein the antiglare hard coat layer of the antireflection film contains matting agent particles having an average particle size of 0.5 to 7 μm.
(14) The polarizing plate according to (1) to (13), wherein the transmitted image clarity of the antireflection film is 10% to less than 65%.
(15) The polarizing plate according to any one of (1) to (14), wherein the layer of the antireflection film contains a surface modifier, and the surface modifier contains a fluoroaliphatic group.
(16) The at least one silica fine particle contained in the low refractive index layer of the antireflection film has an average particle size of 30% or more and 100% or less of the thickness of the low refractive index layer ( The polarizing plate as described in 10)-(15).
(17) The polarized light according to (1) to (16), wherein the low refractive index layer of the antireflection film contains a fluorine-containing polymer, and the fluorine-containing polymer is represented by the following general formula (2): Board.

In the general formula (2), L represents a linking group having 1 to 10 carbon atoms, and m represents 0 or 1. X represents a hydrogen atom or a methyl group. A represents a polymerization unit of any vinyl monomer, and may be composed of a single component or a plurality of components. x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65.
(18) The antireflection film is an antireflection film having an antistatic layer, and the antistatic layer has a surface specific resistance value of 10 ¹¹ Ω / □ or less (25 ° C., 60% RH), and a haze of 20 % Or less, The polarizing plate as described in (1)-(17) characterized by the above-mentioned.
(19) A liquid crystal display device, wherein the polarizing plate according to any one of (1) to (18) is used on the outermost surface of the liquid crystal display device.
(20) The liquid crystal display device according to (19), wherein the liquid crystal cell of the liquid crystal display device is a VA mode or TN mode liquid crystal cell.

  According to the polarizing plate of the present invention, both the optical compensation function and the antireflection function are excellent without increasing the number of components of the polarizing plate, and the effect that the surface scratches are not particularly noticeable when the film is thinned is achieved. Is done. Furthermore, the liquid crystal display device provided with the polarizing plate of the present invention has a wide viewing angle, a small external light source and background reflection, and extremely high visibility.

Hereinafter, the polarizing plate of the present invention will be described in detail.
The polarizing plate of the present invention is a polarizing plate formed by arranging a polarizing film and at least one functional film on each side thereof, and at least one functional film on one side is only a specific cellulose acylate film. The functional film on the other side is made of a specific antireflection film.
Hereinafter, first, the functional film on one side will be described, and then the functional film on the other side and the polarizing plate will be described in order.

<Functional membrane on one side>
In the functional film on one side, at least one functional film is composed of only a specific cellulose acylate film.
[Film retardation]
In this specification, the Re retardation value and the Rth retardation value of each film are defined by the following formulas (I) and (II), respectively.
(I) Re = (nx−ny) × d
(II) Rth = {(nx + ny) / 2−nz} × d
In the formulas (I) and (II), nx is the refractive index in the slow axis direction (direction in which the refractive index is maximum) in the film plane. In the formulas (I) and (II), ny is the refractive index in the fast axis direction (the direction in which the refractive index is minimum) in the film plane. In the formula (II), nz is a refractive index in the thickness direction of the film. In the formulas (I) and (II), d is the thickness of the film whose unit is nm.

The specific cellulose acylate film has an Re retardation value of 20 nm to 70 nm, preferably 40 to 70 nm, and an Rth retardation value of 70 nm to 400 nm, preferably 90 to 250 nm. . If the Re retardation value is less than 20 nm or more than 70 nm, the optical compensation performance is inferior. Similarly, if the Rth retardation value is less than 70 nm or more than 400 nm, the optical compensation performance is inferior. These adjustments can be made according to the type of aromatic compound contained in the cellulose acylate, the amount added, and the draw ratio. In this manner, a cellulose acylate film having optical anisotropy can be obtained.
Specifically, it is preferable to stretch the cellulose acylate film at a stretching ratio of 3 to 100% in order to obtain the above-described retardation values.
The stretching method is not particularly limited, but can be performed by tenter stretching or the like.
The amount of change in Re / Rth per 1% stretch ratio is preferably 0.01 or more and 0.04 or less.
Further, the residual solvent amount of the cellulose acetate film at the time of stretching is preferably 2% or more and 35% or less, more preferably 2% or more and 30% or less, and the direction orthogonal to the longitudinal direction while being conveyed in the longitudinal direction in that state. In order to obtain a retardation value, it is preferable that the film is stretched in the direction perpendicular to the longitudinal direction of the film.
When two optically anisotropic cellulose acylate films are used in a liquid crystal display device, the Rth retardation value of the film is preferably 70 to 200 nm. When a single optically anisotropic cellulose acylate film is used in a liquid crystal display device, the Rth retardation value of the film is preferably 150 to 400 nm.
The birefringence (Δn: nx−ny) of the cellulose acylate film is preferably 0.00025 to 0.00088. The birefringence {(nx + ny) / 2−nz} in the thickness direction of the cellulose acylate film is preferably 0.00088 to 0.005.

The raw material components of the cellulose acylate film will be described.
[Cellulose acylate film]
As the raw material cotton of cellulose acylate used in the present invention, a known raw material can be used, and the synthesis can also be performed by a known method. For example, the Japan Society for Invention and Innovation public technical bulletin number 2001-1
745, Ueda et al., “Wood Chemistry” (Kyoritsu Shuppan, 1968) p. Examples of the raw materials and synthesis methods described in 180-190. The viscosity average degree of polymerization of cellulose acylate is preferably 200 to 700, more preferably 250 to 500, and most preferably 250 to 350.
The cellulose ester used in the present invention preferably has a narrow molecular weight distribution of Mw / Mn (Mw is a weight average molecular weight, Mn is a number average molecular weight) by gel permeation chromatography. The specific value of Mw / Mn is preferably 1.5 to 5.0, more preferably 2.0 to 4.5, and most preferably 3.0 to 4.0. .

As the acyl group of the cellulose acylate film, an acetyl group, a propionyl group, or a butyryl group is preferably used, and a plurality of acyl groups selected from these may be used, and an acetyl group is particularly preferable. The degree of substitution of all acyl groups is preferably 2.7 to 3.0, more preferably 2.8 to 2.95. The degree of substitution of the acyl group in the present invention can be obtained by measuring the degree of binding of the fatty acid bonded to the hydroxyl group in cellulose and calculating it. As a measuring method, it can measure based on ASTM-D-817-91 and ASTM-D-817-96.
The state of substitution of the acyl group with the hydroxyl group is measured by ¹³ C NMR method.
The acyl group is most preferably an acetyl group. When cellulose acetate having an acyl group as the acetyl group is used, the degree of acetylation is preferably 59.0 to 62.5%, and 59.0 to 61.5%. Is more preferable. When the acetylation degree is within this range, Re does not become larger than the desired value due to the conveying tension at the time of casting, the in-plane variation is small, and the retardation value hardly changes depending on the greenhouse degree.
The substitution degree of the acyl group at the 6-position is preferably 0.9 or more from the viewpoint of suppressing variations in Re and Rth.

[Aromatic compound having at least two aromatic rings]
In the present invention, an aromatic compound having at least two aromatic rings is used as a retardation increasing agent in order to adjust the retardation of the cellulose acylate film. The aromatic compound is used in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of cellulose acylate. The aromatic compound is preferably used in the range of 0.05 to 15 parts by mass, more preferably in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the cellulose acylate.
Even if the amount of the aromatic compound used is less than 0.01 parts by mass or exceeds 20 parts by mass, the optical compensation performance is inferior.
Two or more aromatic compounds may be used in combination. The aromatic ring of the aromatic compound includes an aromatic hetero ring in addition to the aromatic hydrocarbon ring.

The aromatic hydrocarbon ring is particularly preferably a 6-membered ring (that is, a benzene ring). The aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring. As the hetero atom, a nitrogen atom, an oxygen atom and a sulfur atom are preferable, and a nitrogen atom is particularly preferable.
Examples of aromatic heterocycles include furan ring, thiophene ring, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, pyrazole ring, furazane ring, triazole ring, pyran ring, pyridine ring , Pyridazine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring.
The aromatic ring includes benzene ring, furan ring, thiophene ring, pyrrole ring, oxazole ring, thiazole ring, imidazole ring, triazole ring, pyridine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring. A benzene ring and a 1,3,5-triazine ring are more preferable. It is particularly preferred that the aromatic compound has at least one 1,3,5-triazine ring.

The number of aromatic rings contained in the aromatic compound is preferably 2 to 20, more preferably 2 to 12, still more preferably 2 to 8, and most preferably 2 to 6. .
The bond relationship of each aromatic ring can be classified into (a) when forming a condensed ring, (b) when directly connecting with a single bond, and (c) when connecting via a linking group (for aromatic rings, Spiro bonds cannot be formed). The connection relationship may be any of (a) to (c). That is, the aromatic compound used in the present invention includes a compound in which each aromatic ring is condensed to form a condensed ring, a compound in which each aromatic ring is directly connected by a single bond, and each aromatic ring Is a compound formed by bonding via a linking group described later.

Examples of the condensed ring of (a) (condensed ring of two or more aromatic rings), that is, the aromatic compound formed with a condensed ring includes an indene ring, naphthalene ring, azulene ring, fluorene ring, phenanthrene ring , Anthracene ring, acenaphthylene ring, naphthacene ring, pyrene ring, indole ring, isoindole ring, benzofuran ring, benzothiophene ring, indolizine ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring, purine ring, Indazole ring, chromene ring, quinoline ring, isoquinoline ring, quinolidine ring, quinazoline ring, cinnoline ring, quinoxaline ring, phthalazine ring, pteridine ring, carbazole ring, acridine ring, phenanthridine ring, xanthene ring, phenazine ring, phenothiazine ring, Phenoxathiin ring, It includes Enokisajin ring and thianthrene ring. Of these, naphthalene ring, azulene ring, indole ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring and quinoline ring are preferred.
The single bond (b) is preferably a bond between carbon atoms of two or more aromatic rings. Two aromatic rings may be bonded with two or more single bonds to form an aliphatic ring or a non-aromatic heterocyclic ring between the two aromatic rings.

The linking group in (c) is also preferably bonded to carbon atoms of two aromatic rings. The linking group is preferably an alkylene group, an alkenylene group, an alkynylene group, —CO—, —O—, —NH—, —S—, or a combination thereof. The alkylene group may have a cyclic structure. As the cyclic alkylene group, cyclohexylene is preferable, and 1,4-cyclohexylene is particularly preferable. As the chain alkylene group, an unbranched linear structure is preferable. The number of carbon atoms in the alkylene group is preferably 1-20, and more preferably 1-8. The alkenylene group and alkynylene group preferably have a chain structure rather than a cyclic structure, and more preferably have an unbranched linear structure. The alkenylene group and the alkynylene group preferably have 2 to 10 carbon atoms, and more preferably 2 to 4 carbon atoms.
Examples of linking groups composed of combinations are shown below. In addition, the relationship between the left and right in the following examples of the linking group may be reversed.
c1: -CO-O-
c2: —CO—NH—
c3: -alkylene-O-
c4: —NH—CO—NH—
c5: —NH—CO—O—
c6: —O—CO—O—
c7: -O-alkylene-O-
c8: -CO-alkenylene-
c9: -CO-alkenylene-NH-
c10: -CO-alkenylene-O-
c11: -alkylene-CO-O-alkylene-O-CO-alkylene-
c12: -O-alkylene-CO-O-alkylene-O-CO-alkylene-O-
c13: -O-CO-alkylene-CO-O-
c14: -NH-CO-alkenylene-
c15: -O-CO-alkenylene-

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

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

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

The alkylthio group preferably has 1 to 12 carbon atoms. Examples of the alkylthio group include methylthio, ethylthio and octylthio. The alkylsulfonyl group preferably has 1 to 8 carbon atoms.
Examples of the alkylsulfonyl group include methanesulfonyl and ethanesulfonyl.
The aliphatic amide group preferably has 1 to 10 carbon atoms. Examples of the aliphatic amide group include acetamide.
The aliphatic sulfonamide group preferably has 1 to 8 carbon atoms. Examples of the aliphatic sulfonamido group include methanesulfonamido, butanesulfonamido and n-octanesulfonamido.
The number of carbon atoms of the aliphatic substituted amino group is preferably 1 to 10. Examples of the aliphatic substituted amino group include dimethylamino, diethylamino and 2-carboxyethylamino.
The aliphatic substituted carbamoyl group preferably has 2 to 10 carbon atoms. Examples of the aliphatic substituted carbamoyl group include methylcarbamoyl and diethylcarbamoyl.
The aliphatic substituted sulfamoyl group preferably has 1 to 8 carbon atoms. Examples of the aliphatic substituted sulfamoyl group include methylsulfamoyl and diethylsulfamoyl. The number of carbon atoms in the aliphatic substituted ureido group is preferably 2 to 10.
Examples of the aliphatic substituted ureido group include methylureido.
Examples of non-aromatic heterocyclic groups include piperidino and morpholino.
Among the above-described examples, the aromatic compound is preferably a rod-like compound having a linear molecular structure. By linear molecular structure is meant linear in the most thermodynamically stable structure. The most thermodynamically stable structure can be obtained by crystal structure analysis or molecular orbital calculation. For example, molecular orbital calculation can be performed using molecular orbital calculation software (eg, WinMOPAC2000, manufactured by Fujitsu Limited) to obtain a molecular structure that minimizes the heat of formation of the compound. The linear molecular structure means that the angle of the molecular structure is 140 degrees or more in the thermodynamically most stable structure obtained by calculation as described above.
Specific examples of the aromatic compound having at least two aromatic rings include, but are not limited to, the following compounds.

  The molecular weight of the retardation increasing agent is preferably 300 to 800.

[Manufacture of cellulose acylate film]
Regarding the production of the cellulose acylate film, it is preferable to use the method of Patent Document 4. For example, Patent Document 4 also describes solution preparation, casting methods, plasticizers, deterioration inhibitors, and the like, and it is preferable to use this method and materials. The draw ratio is preferably 3 to 100
%, More preferably 5 to 80%.
Tenter stretching is preferably used as the stretching method from the viewpoint of in-plane uniformity. The stretching treatment may be performed in the middle of the film forming process, or the raw film that has been formed and wound may be stretched. In the former case, the film may be stretched in a state containing a residual solvent, and the residual solvent is preferably stretched at 2 to 35%, more preferably 2 to 30%.
The thickness of the cellulose acylate film is preferably 30 to 140 μm, more preferably 40 to 90 μm, and still more preferably 40 to 70 μm.
As for the surface treatment of the cellulose acylate film, alkali saponification treatment described later in <Regarding the functional membrane on the other side> can be mentioned. Moreover, the method described in patent document 4 [surface treatment of a cellulose acetate film] can also be used.
In the present invention, the functional film on the one side may be formed by only a functional film made of only the cellulose acylate film, or may be formed by overlapping the film with another functional film. Examples of the other functional film include a retardation changing film of the cellulose acylate film, a normal blank cellulose acylate film, and the like.

<About the functional membrane on the other side>
Next, the functional film on the other side will be described.
The functional film on the other side is an antireflection film having a plurality of layers. Each layer constituting the antireflection film comprises an antiglare hard coat layer, a hard coat layer having no antiglare property, a medium refractive index layer or a high refractive index layer, and a low refractive index layer. Have at least. The hard coat layer having no antiglare property may also serve as a light diffusion layer. It is also preferable to provide an antistatic layer between the transparent support and the hard coat layer. The hard coat layer may be composed of one layer or a plurality of layers. The low refractive index layer is preferably applied as the outermost layer.
A basic configuration of an antireflection film suitable as an embodiment of the present invention will be described with reference to the drawings.
Here, FIG.1 and FIG.2 is sectional drawing which shows the structure of an antireflection film typically.
An antireflection film 1 schematically shown in FIG. 1 includes a transparent support 2, a hard coat layer 3 formed on the transparent support, an antiglare hard coat layer 4 formed on the hard coat layer 3, and It consists of the low refractive index layer 5 formed as the outermost layer. Matting agent particles 6 are dispersed in the antiglare hard coat layer 4. The hard coat layer 3 is not necessarily required, and an antiglare hard coat layer may be directly provided on the transparent support 2. A medium refractive index layer 7 and a high refractive index layer 8 may be provided on the antiglare hard coat layer 4 in the same manner as in FIG.

The antireflection film schematically shown in FIG. 2 includes a transparent support 2, a hard coat layer 3 formed on the transparent support 2, a medium refractive index layer 7 formed on the hard coat layer 3, and a medium refractive index. It consists of a high refractive index layer 8 formed on the layer 7 and a low refractive index layer 5 formed as the outermost layer.
It is also preferable to coat an antistatic layer under the hard coat layer. The transparent support 2, the medium refractive index layer 7, the high refractive index layer 8, and the low refractive index layer 5 have refractive indexes that satisfy the following relationship.
Refractive index of high refractive index layer> refractive index of medium refractive index layer> refractive index of transparent support> refractive index of low refractive index layer The layer structure as shown in FIG. It is preferable that the film is an antireflection film that satisfies the following conditions, and more preferable that the following conditions are satisfied.
Each condition is represented by the following formula (III) for the medium refractive index layer, the following formula (IV) for the high refractive index layer, and the following formula (V) for the low refractive index layer.
Here, λ is 500 nm, h is 1, i is 2, and j is 1.
Formula (III)
(Hλ / 4) × 0.80 <n ₁ d ₁ <(hλ / 4) × 1.00
Formula (IV)
(Iλ / 4) × 0.75 <n ₂ d ₂ <(iλ / 4) × 0.95
Formula (V)
(Jλ / 4) × 0.95 <n ₃ d ₃ <(jλ / 4) × 1.05

The high refractive index, medium refractive index, and low refractive index described here refer to the relative refractive index between layers. Moreover, in FIG. 2, the high refractive index layer is used as an optical interference layer, and an antireflection film having extremely excellent antireflection performance can be produced.
Further, the hard coat layer in the antireflection film shown in FIG. 2 may be a hard coat layer having no antiglare property or an antiglare hard coat layer.

[Organosilane compound and / or its hydrolyzate and / or its partial condensate]
Each layer constituting the antireflection film of the present invention contains an organosilane compound and / or a hydrolyzate thereof and / or a partial condensate thereof, a so-called sol component (hereinafter referred to as this) in the coating solution forming the layer. It is preferable from the viewpoint of scratch resistance. It is more preferable to contain the compound in a hard coat layer, an antiglare hard coat layer, and a low refractive index layer. In particular, the liquid for the low refractive index layer preferably contains an organosilane compound, a hydrolyzate thereof and / or a partial condensate thereof in order to achieve both antireflection performance and scratch resistance. The liquid for the antiglare hard coat layer preferably contains an organosilane compound, a hydrolyzate thereof and / or a partial condensate thereof, or a mixture thereof. This sol component is condensed by a drying and heating process after coating the coating solution to form a cured product, which becomes a binder for the layer. Moreover, when this hardened | cured material has a polymerizable unsaturated bond, the binder which has a three-dimensional structure is formed by irradiation of actinic light.

The organosilane compound is preferably represented by the following general formula (1).
Formula _{^{(1) (R 10) m}} -Si (X) 4-m
In the general formula (1), R ¹⁰ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, hexyl, decyl, hexadecyl and the like. The alkyl group preferably has 1 to 30 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 6 carbon atoms. Examples of the aryl group include phenyl and naphthyl, and a phenyl group is preferable.
X represents a hydroxyl group or a hydrolyzable group, and examples of the hydrolyzable group include an alkoxy group (preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group and an ethoxy group), and a halogen atom. (For example, Cl, Br, I, etc.) and R ² COO (R ² represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Examples include CH ₃ COO, C ₂ H ₅ COO, etc.). And preferably an alkoxy group, particularly preferably a methoxy group or an ethoxy group.
m represents an integer of 1 to 3, preferably 1 or 2, and particularly preferably 1.

When R ¹⁰ or X there are a plurality, a plurality of R ¹⁰ or X groups may be different, even the same, respectively.
The substituent contained in R ¹⁰ is not particularly limited, but a halogen atom (fluorine, chlorine, bromine, etc.), hydroxyl group, mercapto group, carboxyl group, epoxy group, alkyl group (methyl, ethyl, i-propyl, propyl, t-butyl etc.), aryl groups (phenyl, naphthyl etc.), aromatic heterocyclic groups (furyl, pyrazolyl, pyridyl etc.), alkoxy groups (methoxy, ethoxy, i-propoxy, hexyloxy etc.), aryloxy (phenoxy etc.) ), Alkylthio groups (methylthio, ethylthio, etc.), arylthio groups (phenylthio, etc.), alkenyl groups (vinyl, 1-propenyl, etc.), acyloxy groups (acetoxy, acryloyloxy, methacryloyloxy, etc.), alkoxycarbonyl groups (methoxycarbonyl, ethoxy) Carbonyl, etc.), aryloxy Carbonyl groups (phenoxycarbonyl, etc.), carbamoyl groups (carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-methyl-N-octylcarbamoyl, etc.), acylamino groups (acetylamino, benzoylamino, acrylicamino, methacrylamino) Etc.), and these substituents may be further substituted.

  Two or more compounds of the general formula (1) may be used in combination. Although the specific example of a compound represented by General formula (1) below is shown, it is not limited.

  Of these, (M-1), (M-2), and (M-5) are particularly preferable.

The hydrolyzate and / or partial condensate of the organosilane compound used in the present invention will be described in detail.
The hydrolysis reaction and / or condensation reaction of organosilane is generally performed in the presence of a catalyst. Catalysts include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid; organic acids such as oxalic acid, acetic acid, formic acid, methanesulfonic acid and toluenesulfonic acid; inorganic bases such as sodium hydroxide, potassium hydroxide and ammonia; triethylamine, Examples thereof include organic bases such as pyridine; metal alkoxides such as triisopropoxyaluminum and tetrabutoxyzirconium; metal chelate compounds having a metal such as Zr, Ti or Al as a central metal.

  The organosilane hydrolysis / condensation reaction can be carried out in the absence of a solvent or in a solvent, but an organic solvent is preferably used in order to mix the components uniformly. For example, alcohols, aromatic hydrocarbons, ethers, Ketones and esters are preferred.

0.3 to 2 mol, preferably 0.5 to 1 mol of water is added to 1 mol of hydrolyzable group of the organosilane, in the presence or absence of the solvent and in the presence of the catalyst. It is carried out by stirring at 25 to 100 ° C.
In the present invention, (wherein, R ³ represents an alkyl group having 1 to 10 carbon atoms) Formula R ³ OH alcohol of the general formula R ⁴ COCH ₂ COR ⁵ (formula represented by, R ⁴ is carbon From Zr, Ti, or Al having a ligand represented by a compound represented by an alkyl group having 1 to 10 carbon atoms, R ⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms) It is preferable to perform hydrolysis by stirring at 25 to 100 ° C. in the presence of at least one metal chelate compound having a selected metal as a central metal.

The metal chelate compound includes an alcohol represented by the general formula R ³ OH (wherein R ³ represents an alkyl group having 1 to 10 carbon atoms) and R ⁴ COCH ₂ COR ⁵ (wherein R ⁴ is 1 carbon atom). -10 alkyl group, R ⁵ is an alkyl group having 1 to 10 carbon atoms or a compound represented by an alkoxy group having 1 to 10 carbon atoms), and is selected from Zr, Ti, and Al. Any metal having a metal as a central metal can be suitably used without particular limitation. Within this category, two or more metal chelate compounds may be used in combination. Specific examples of the metal chelate compound used in the present invention include tri-n-butoxyethyl acetoacetate zirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate) zirconium, tetrakis (n Zirconium chelate compounds such as propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium; diisopropoxy bis (ethylacetoacetate) titanium, diisopropoxy bis (acetylacetate) titanium , Titanium chelate compounds such as diisopropoxy bis (acetylacetone) titanium; diisopropoxyethyl acetoacetate aluminum Diisopropoxyacetylacetonate aluminum, isopropoxybis (ethylacetoacetate) aluminum, isopropoxybis (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonate bis (Ethyl acetoacetate) Aluminum chelate compounds such as aluminum can be mentioned.
Among these metal chelate compounds, preferred are tri-n-butoxyethyl acetoacetate zirconium, diisopropoxy bis (acetylacetonate) titanium, diisopropoxyethyl acetoacetate aluminum, and tris (ethyl acetoacetate) aluminum. . These metal chelate compounds can be used individually by 1 type or in mixture of 2 or more types. Moreover, the partial hydrolyzate of these metal chelate compounds can also be used.

  The metal chelate compound of the present invention is preferably 0.01 to 50% by mass, more preferably 0.1 to 50%, based on the organosilane, from the viewpoint of the speed of the condensation reaction and the film strength when formed into a coating film. It is used at a ratio of 0.5% by mass, more preferably 0.5-10% by mass.

  In addition to the composition containing the hydrolyzate and / or partial condensate of the organosilane compound and the metal chelate compound in the coating solution for the antiglare hard coat layer to the low refractive index layer used in the present invention, β-diketone It is preferred that a compound and / or a β-ketoester compound is added.

What is used in the present invention is a β-diketone compound and / or β-ketoester compound represented by the general formula R ⁴ COCH ₂ COR ⁵ , and an antiglare hard coat layer or a low refractive index used in the present invention. It acts as a stability improver for the forming composition of the layer. Here, R ⁴ represents an alkyl group having 1 to 10 carbon atoms, and R ⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms. R ⁴ and R ⁵ constituting the β- diketone compound and / or β- ketoester compound are the same as R ⁴ and R ⁵ constituting the metal chelate compound.

  Specific examples of the β-diketone compound and / or β-ketoester compound include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate. Acetic acid-sec-butyl, acetoacetic acid-t-butyl, 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane -Dione, 5-methyl-hexane-dione and the like can be mentioned. Of these, ethyl acetoacetate and acetylacetone are preferred, and acetylacetone is particularly preferred. These β-diketone compounds and / or β-ketoester compounds may be used alone or in combination of two or more. In the present invention, the β-diketone compound and / or β-ketoester compound is preferably used in an amount of 2 mol or more, more preferably 3 to 20 mol, per 1 mol of the metal chelate compound. If it is less than 2 mol, the storage stability of the resulting composition may be inferior, which is not preferable.

The content of the hydrolyzate and / or partial condensate of the organosilane compound is preferably small for the surface layer that is a relatively thin film and large for the lower layer that is a thick film. In the case of a surface layer such as a low refractive index layer, 0.1 to 50% by mass of the total solid content of the containing layer (addition layer) is preferable, 0.5 to 20% by mass is more preferable, and 1 to 10% by mass is preferable. Most preferred.
The amount added to the layers other than the low refractive index layer is preferably 0.001 to 50 mass%, more preferably 0.01 to 20 mass%, and more preferably 0.05 to 10 mass% of the total solid content of the containing layer (addition layer). More preferably, it is 0.1 to 5% by mass.
In the present invention, first, a composition containing a hydrolyzate and / or partial condensate of the organosilane compound and a metal chelate compound is prepared, and a liquid obtained by adding a β-diketone compound and / or a β-ketoester compound thereto is prepared. It is preferable to coat by coating it in at least one coating solution of a hard coat layer or a low refractive index layer.

  5-100 mass% is preferable, as for the usage-amount of the sol component of the organosilane with respect to the fluorine-containing polymer (It mentions later in [low refractive index layer]) in a low refractive index layer, 5-40 mass% is more preferable, 8- 35 mass% is still more preferable, and 10-30 mass% is especially preferable. If the amount used is small, it is difficult to obtain the effect of the present invention, and if the amount used is too large, the refractive index increases or the shape / surface shape of the film deteriorates.

[Inorganic fine particles that can be contained in the low refractive index layer]
Next, the inorganic fine particles that can be contained in the low refractive index layer of the present invention will be described.
The coating amount of the inorganic fine particles is preferably ^{1mg / m 2 ~100mg / m 2} , more preferably ^{5mg / m 2 ~80mg / m 2} , more preferably from ^{10mg / m 2 ~60mg / m 2} . If the amount is too small, the effect of improving the scratch resistance is reduced. If the amount is too large, fine irregularities are formed on the surface of the low refractive index layer, and the appearance such as black tightening and the integrated reflectance may be deteriorated. It is preferable to be inside.
Since the inorganic fine particles are contained in the low refractive index layer, it is desirable that the inorganic fine particles have a low refractive index. Examples thereof include fine particles of magnesium fluoride and silica. In particular, silica fine particles are preferable in terms of refractive index, dispersion stability, and cost. The average particle diameter of the silica fine particles is preferably 20% or more and 150% or less of the thickness of the low refractive index layer, more preferably 30% or more and 100% or less, and further preferably 40% or more and 60% or less. That is, when the thickness of the low refractive index layer is 100 nm, the particle diameter of the silica fine particles is preferably 20 nm or more and 150 nm or less, more preferably 30 nm or more and 100 nm or less, and still more preferably 40 nm or more and 60 nm or less.
If the particle size of the silica fine particles is too small, the effect of improving the scratch resistance is reduced. If the particle size is too large, fine irregularities are formed on the surface of the low refractive index layer, and the appearance such as black tightening and the integrated reflectance may be deteriorated. Therefore, it is preferable to be within the above-mentioned range. The silica fine particles may be either crystalline or amorphous, and may be monodispersed particles or aggregated particles as long as a predetermined particle size is satisfied. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.
Here, the average particle diameter of the inorganic fine particles is measured by a Coulter counter.

In order to further reduce the increase in the refractive index of the low refractive index layer, it is preferable to use hollow silica fine particles, and the hollow silica fine particles preferably have a refractive index of 1.17 to 1.40, more preferably 1.17. -1.35, more preferably 1.17-1.30. The refractive index here represents the refractive index of the entire particle, and does not represent the refractive index of only the outer shell silica forming the hollow silica particles. At this time, if the radius of the cavity in the particle is a and the radius of the particle outer shell is b, the porosity x is expressed by the following formula (VIII).
(Formula VIII)
^{x = (4πa 3/3)} / (4πb 3/3) × 100
The porosity x is preferably 10 to 60%, more preferably 20 to 60%, and most preferably 30 to 60%.
If the hollow silica particles are made to have a lower refractive index and a higher porosity, the thickness of the outer shell becomes thinner and the strength of the particles becomes weaker. From the viewpoint of scratch resistance, the low refractive index is less than 1.17. Rate particles do not hold.
The refractive index of these hollow silica particles was measured with an Abbe refractometer (manufactured by Atago Co., Ltd.).

Further, at least one kind of silica fine particles having an average particle size of less than 25% of the thickness of the low refractive index layer (referred to as “small size particle size silica particles”) is used as the silica fine particles having the above particle size (“large size particles”). It is also preferred to use in combination with “diameter silica fine particles”.
Since the fine silica particles having a small size can be present in the gaps between the fine silica particles having a large size, the fine particles can contribute as a retaining agent for the fine silica particles having a large size.
When the low refractive index layer is 100 nm, the average particle size of the silica fine particles having a small size is preferably from 1 nm to 20 nm, more preferably from 5 nm to 15 nm, and particularly preferably from 10 nm to 15 nm. Use of such silica fine particles is preferable in terms of raw material costs and a retaining agent effect.
When the large particle size silica particles and the small particle size silica particles are used in combination, it is preferably used within 100 parts by mass with respect to 100 parts by mass of the large particle size silica particles.

Silica fine particles are treated with a physical surface treatment such as plasma discharge treatment or corona discharge treatment in order to stabilize dispersion in the dispersion or coating solution, or to increase the affinity and binding to the binder component. Further, chemical surface treatment with a surfactant, a coupling agent or the like may be performed. The use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Among these, silane coupling treatment is particularly effective.
The coupling agent is used as a surface treatment agent for the inorganic filler of the low refractive index layer in advance for surface treatment prior to preparation of the layer coating solution, and is further added as an additive during preparation of the layer coating solution. It is preferable to make it contain in a layer.
The silica fine particles are preferably dispersed in the medium in advance before the surface treatment in order to reduce the load of the surface treatment.
What has been described above for silica fine particles also applies to other inorganic fine particles.

[Surface modifier]
In the present invention, a fluoroaliphatic group-containing polymer (hereinafter, also simply referred to as “fluorine polymer”) can be used as a surface modifier in each layer constituting the antireflection film. Hereinafter, the fluoroaliphatic machine-containing monomer which is a material for forming the fluoroaliphatic group-containing polymer used in the present invention will be described.
The functional layer in the present invention may be either an optical functional layer or a physical functional layer. Examples of the optical functional layer include a high refractive index layer and a light diffusion layer. Examples of the physical functional layer include a hard coat layer. Can be mentioned. It may be a layer that serves as both functional layers, such as an antiglare hard coat layer.

The amount of the fluoroaliphatic group-containing monomer used in the present invention is 50 mol% or more, preferably 70 to 100 mol%, more preferably 80 to 100 mol, based on each monomer of the fluoropolymer. % Range.
The preferred weight average molecular weight of the fluoroaliphatic group-containing polymer used in the present invention is preferably from 3,000 to 100,000, more preferably from 6,000 to 80,000, and even more preferably from 8,000 to 60,000.
Furthermore, the preferable addition amount of the fluoroaliphatic group-containing polymer used in the present invention is in the range of 0.001 to 5% by mass, preferably in the range of 0.005 to 3% by mass with respect to the coating solution. More preferably, it is the range of 0.01-1 mass%. If the addition amount of the fluoropolymer is less than 0.001% by mass, the effect is insufficient, and if it is more than 5% by mass, the coating film may be insufficiently dried or a surface failure may occur.

  The example of the specific structure of the fluoro aliphatic group containing polymer contained in the functional layer of this invention is shown. In addition, the number in a formula shows the molar ratio of each monomer component. Mw represents a mass average molecular weight.

Next, each layer constituting the antireflection film of the present invention will be described.
In the present invention, as described above, examples of the hard coat layer to be used include an antiglare hard coat layer and a hard coat layer having no antiglare property. First, the antiglare property will be described.

[Anti-glare]
The antiglare property is usually determined by sensory evaluation of a film sample with the back side painted black. However, in order to provide objectivity, correlation with an optical measurement value is also performed. The correlation differs depending on the coating formulation and the layer structure, and for example, a certain relationship is often observed with, for example, haze, transmitted image clarity, and scattering angle distribution. In the antireflection film of the present invention, there was a correlation with transmitted image clarity.
In order to reduce the influence of scratches and avoid image blurring, the transmitted image sharpness is preferably 10% to 99%.
When the hard coat layer in the present invention is antiglare (when it is an antiglare hard coat layer), the transmitted image clarity is preferably 10% to less than 65%, more preferably 10% to 55%, and 15 % To 50% is most preferred. When the hard coat layer in the present invention is not antiglare (when it is a hard coat layer having no antiglare property), the transmitted image clarity is preferably 65% to 99%, and preferably 70% to 99%. More preferably, 80% to 99% is most preferable.

[Hard coat layer]
The hard coat layer is a so-called smooth hard coat layer that is used for imparting physical strength to the antireflection film and is not anti-glare, and as shown in FIGS. 1 and 2, particularly on the surface of the transparent support, The transparent support and the antiglare hard coat layer, the transparent support and the light diffusion layer, and the transparent support and the high refractive index layer are preferably provided.
The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. For example, it may be formed by applying a coating composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer on a transparent support and subjecting the polyfunctional monomer or polyfunctional oligomer to a crosslinking reaction or a polymerization reaction. it can.
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. Specific examples of the polyfunctional monomer include polyfunctional monomers described in JP-A No. 2003-4903.

The hard coat layer preferably contains inorganic fine particles having an average primary particle size of 200 nm or less. The average particle diameter here is a mass average diameter. By setting the average particle size of the primary particles to 200 nm or less, a hard coat layer that does not impair the transparency can be formed.
As inorganic fine particles, in addition to the inorganic fine particles exemplified in the high refractive index layer, silicon dioxide, aluminum oxide, calcium carbonate, barium sulfate, talc, kaolin, calcium sulfate, titanium dioxide, zirconium oxide, tin oxide, ITO, zinc oxide, etc. Fine particles. Preferred are silicon dioxide, titanium dioxide, zirconium oxide, aluminum oxide, tin oxide, ITO, and zinc oxide.
The preferable average particle size of the primary particles of the inorganic fine particles and the average particle size of the actual dispersed particles in the hard coat layer are the same as those of the high refractive index layer described later. The content of the inorganic fine particles in the hard coat layer is preferably 10 to 90% by mass, more preferably 15 to 80% by mass, and particularly preferably 15 to 75% by mass with respect to the total mass of the hard coat layer.

  The film thickness of the hard coat layer can be appropriately designed depending on the application. The film thickness of the hard coat layer is preferably 0.2 to 10 μm, more preferably 0.5 to 7 μm, and particularly preferably 0.7 to 5 μm.

The strength of the hard coat layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in a pencil hardness test according to JIS K5400.
Further, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.
In the formation of the hard coat layer, the oxygen concentration when formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound is the same as that of the high refractive index layer described later.

[Anti-glare hard coat layer]
Next, the antiglare hard coat layer will be described below.
The antiglare hard coat layer is a layer that is always used as either a high refractive index layer or a high refractive index layer. Further, inorganic fine particles are contained as necessary for increasing the refractive index, preventing crosslinking shrinkage, and increasing the strength.
As the binder, a binder polymer having a saturated hydrocarbon chain or a polyether chain as a main chain is preferable, and a binder polymer having a saturated hydrocarbon chain as a main chain is more preferable. The binder polymer preferably has a crosslinked structure.
As the binder polymer having a saturated hydrocarbon chain as a main chain, a polymer of an ethylenically unsaturated monomer is preferable. As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable.
In order to obtain a high refractive index, the monomer structure preferably contains an aromatic ring or at least one atom selected from halogen atoms other than fluorine, sulfur atoms, phosphorus atoms, and nitrogen atoms.

As the monomer having two or more ethylenically unsaturated groups, it is preferable to use a polyfunctional monomer described in JP-A No. 2003-4903.
Specific examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like. Two or more of these monomers may be used in combination.
In the present invention, the binder and the coating film refer to a layer structure excluding the matting agent particles and have the same meaning.

  The antiglare hard coat layer is prepared by preparing a coating liquid containing a monomer having an ethylenically unsaturated group which is a material for forming a binder polymer, a photo radical initiator or a thermal radical initiator, matting agent particles and inorganic fine particles, It can be formed by applying the coating solution on a transparent support and then curing it by ionizing radiation or a polymerization reaction with heat.

As the photo radical initiator, it is preferable to use a compound described in JP-A No. 2003-4903. Preferable examples of commercially available photocleavable photoradical polymerization initiators include Irgacure (651, 184, 907) manufactured by Nippon Ciba-Geigy Co., Ltd.
The photo radical initiator is preferably used in the range of 0.1 to 15 parts by mass, more preferably in the range of 1 to 10 parts by mass with respect to 100 parts by mass of the polyfunctional monomer.
In addition to the photo radical initiator, a photo sensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.

As the thermal radical initiator, organic or inorganic peroxides, organic azo, diazo compounds, and the like can be used.
Specifically, benzoyl peroxide, halogen benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide as organic peroxides, hydrogen peroxide, peroxides as inorganic peroxides. Ammonium sulfate, potassium persulfate, etc., 2-azo-bis-isobutyronitrile, 2-azo-bis-propionitrile, 2-azo-bis-cyclohexanedinitrile, etc. as diazo compounds, diazoaminobenzene, p-nitrobenzenediazonium Etc.

  A coating solution containing a polyfunctional epoxy compound, a photoacid generator or thermal acid generator, matting agent particles and an inorganic filler is prepared, and the coating solution is applied on a transparent support and then cured by ionizing radiation or heat polymerization. It is also possible to form an antiglare hard coat layer.

Instead of or in addition to a monomer having two or more ethylenically unsaturated groups, a monomer having a crosslinkable functional group is used to introduce a crosslinkable functional group into the polymer, and by reaction of this crosslinkable functional group, A crosslinked structure may be introduced into the binder polymer.
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 for introducing 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 binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.

The matting agent particles are used for the purpose of imparting antiglare properties, and preferably have an average particle size of 0.5 to 10 μm, more preferably 0.5 to 7.0 μm.
The amount of the matting agent particles is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² . Since the particle size and content affect the antiglare property, they are adjusted depending on the layer thickness and the target antiglare property.
Specific examples of the matting agent particles include inorganic compound particles such as silica particles and TiO ₂ particles; acrylic particles, crosslinked acrylic particles, methacrylic particles, crosslinked methacrylic particles, polystyrene particles, crosslinked styrene particles, melamine resin particles, benzoguanamine. Resin particles such as resin particles are preferred. Of these, crosslinked styrene particles, crosslinked acrylic particles, and silica particles are preferred.
The shape of the matting agent particles may be either a true sphere or an indefinite shape, but is preferably monodispersed. Two or more kinds of matting agent particles having different particle diameters may be used in combination.
The particle size distribution of the matting agent particles is converted from the distribution measured by the Coulter counter method into the particle number distribution.

In order to increase the refractive index and elastic modulus of the layer, the antiglare hard coat layer is composed of at least one metal oxide in addition to the matting agent particles, and has an average particle diameter in a dispersed state. Is preferably 200 nm or less, preferably 100 nm or less, more preferably 60 nm or less. As the inorganic fine particles, those specifically exemplified as the inorganic fine particles to be contained in the antiglare layer in JP-A No. 2003-4903 are preferably used. The average particle size of the primary particles is preferably 1 to 200 nm, more preferably 2 to 100 nm, and further preferably 3 to 50 nm.
The surface of the inorganic fine particles is also preferably subjected to silane coupling treatment or titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with the binder species on the fine particle surface is preferably used.
The addition amount of these inorganic fine particles is preferably 10 to 90% of the total mass of the antiglare hard coat layer, more preferably 20 to 80%, and particularly preferably 30 to 75%.
Such inorganic fine particles have a particle size sufficiently smaller than the wavelength of light and therefore do not scatter, and a dispersion in which the filler is dispersed in a binder polymer behaves as an optically uniform substance.

The bulk refractive index of the mixture of the binder and inorganic fine particles of the antiglare hard coat layer of the present invention is preferably 1.48 to 2.00, more preferably 1.50 to 1.80.
The difference in refractive index between the matting agent particles and the binder (the refractive index of the matting agent particles−the refractive index of the binder) is preferably 0.03 to 0.2, more preferably 0.05 to 0.15. It is. By setting this difference to 0.03 or more, antiglare property is efficiently expressed, and by setting it to 0.2 or less, it is possible to suppress an increase in cost without increasing whiteness too much.
The refractive index of the binder is preferably 1.48 to 1.8. The refractive index of the matting agent particles is preferably 1.3 to 1.8.
The refractive index of the binder can be measured with an Abbe refractometer (manufactured by ATAGO) or an ellipsometer (JASCO Corporation).
In order to set the refractive index within the above range, the type and amount ratio of the binder and the inorganic fine particles may be appropriately selected, and the selection content can be easily known experimentally in advance.
The film thickness of the antiglare hard coat layer is preferably 1 to 10 μm, and more preferably 2 to 6 μm.

[Light diffusion layer]
It is also preferable to provide a light diffusion layer as one of the layers constituting the functional layer. The present inventors have confirmed that the intensity distribution of scattered light measured with a goniophotometer correlates with the viewing angle improvement effect. That is, the more the light emitted from the backlight is diffused by the light diffusion film installed on the polarizing plate surface on the viewing side, the better the viewing angle characteristics. However, if it is diffused too much, backscattering will increase and the front luminance will decrease, or the scattering will be too great and the image clarity will deteriorate. Therefore, it is necessary to control the scattered light intensity distribution within a certain range. Therefore, as a result of intensive studies, in order to achieve the desired visual characteristics, the scattered light intensity at 30 °, which correlates particularly with the visual angle improvement effect, is 0.01 with respect to the light intensity at the output angle 0 ° of the scattered light profile. % To 0.2% is preferable, 0.02% to 0.15% is more preferable, and 0.03% to 0.1% is particularly preferable.
The scattered light profile can be measured using the automatic variable angle photometer GP-5 manufactured by Murakami Color Research Laboratory Co., Ltd. for the created light scattering film.
In the layer classification of the antireflection film of the present invention, the light diffusion layer can correspond to at least one of an antiglare hard coat layer and a high refractive index layer depending on the transmitted image definition or refractive index value.

[High refractive index layer, middle refractive index layer]
In the antireflection film, a high refractive index layer is also selectively used with the antiglare hard coat layer in order to impart better antireflection ability.
The refractive index of the high refractive index layer is 1.55 to 2.40, and if there is a layer within this range, it can be said that the high refractive index layer in the present invention exists. The range of this refractive index is a range called a so-called high refractive index layer or medium refractive index layer, but in the following specification, these layers may be collectively referred to as a high refractive index layer.
When the high refractive index layer and the middle refractive index layer are mixed as shown in the structure shown in FIG. A layer of less than .8 to 1.55 is referred to as a medium refractive index layer, but the relationship of high / medium refractive index is relative, and the boundary refractive index value may move by about 0.2. The refractive index can be appropriately adjusted depending on the kind and ratio of the inorganic fine particles and binder to be added.

[Inorganic fine particles that can be contained in the high refractive index layer]
The high refractive index layer contains inorganic fine particles mainly composed of titanium dioxide containing at least one element selected from cobalt, aluminum, and zirconium. The main component means a component having the largest content (mass%) among the components constituting the particles.
The inorganic fine particles mainly composed of titanium dioxide in the present invention preferably have a refractive index of 1.90 to 2.80, and most preferably 2.20 to 2.80. The mass average diameter of the primary particles is preferably 1 to 200 nm, more preferably 2 to 100 nm, and particularly preferably 2 to 80 nm.

By incorporating at least one element selected from Co, Al and Zr into inorganic fine particles mainly composed of titanium dioxide, the photocatalytic activity of titanium dioxide can be suppressed, and the weather resistance of the high refractive index layer is improved. can do.
The inorganic fine particles mainly composed of titanium dioxide used in the present invention may be surface-treated. The surface treatment is performed using an inorganic compound containing cobalt, an inorganic compound such as Al (OH) ₃ or Zr (OH) ₄ , or an organic compound such as a silane coupling agent. The inorganic fine particles mainly composed of titanium dioxide of the present invention may have a core / shell structure by surface treatment as described in JP-A No. 2001-166104.
The shape of the inorganic fine particles mainly composed of titanium dioxide contained in the high refractive index layer is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape or an indefinite shape, and particularly preferably an indefinite shape or a spindle shape. is there.

[Dispersant]
A dispersant can be used for dispersing the inorganic fine particles. For dispersion, it is particularly preferable to use a dispersant having an anionic group.
As the anionic group, a group having an acidic proton such as a carboxyl group, a sulfonic acid group (and a sulfo group), a phosphoric acid group (and a phosphono group), or a sulfonamide group, or a salt thereof is effective. A sulfonic acid group, a phosphoric acid group and a salt thereof are preferable, and a carboxyl group and a phosphoric acid group are particularly preferable. The number of anionic groups contained in the dispersant per molecule may be one or more, but it is preferably 2 or more on average, more preferably 5 or more, and particularly preferably 10 It is more than one. Multiple types of anionic groups may be contained in one molecule. Furthermore, the dispersant preferably contains a cross-linkable or polymerizable functional group.
The dispersant is preferably 0.5 to 40% by mass, more preferably 1 to 30% by mass, and particularly preferably 3 to 25% by mass with respect to the inorganic fine particles.

[High refractive index layer and formation method thereof]
The inorganic fine particles mainly composed of titanium dioxide used for the high refractive index layer are used for forming the high refractive index layer in a dispersion state.
In the dispersion of the inorganic fine particles, it is dispersed in a dispersion medium in the presence of the dispersant.
As the dispersion medium, a liquid having a boiling point of 60 to 170 ° C. is preferably used. Examples of the dispersion medium include water, alcohol, ketone, ester, aliphatic hydrocarbon, halogenated hydrocarbon, aromatic hydrocarbon, amide, ether, ether alcohol. Toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are preferred.
Particularly preferred dispersion media are methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.
The dispersion medium is preferably 3000 to 100% by mass with respect to the inorganic fine particles, and 20
More preferably, it is 00 to 125% by mass.

The inorganic fine particles are dispersed using a disperser. Examples of dispersers include sand grinder mills (eg, pin bead mills), high speed impeller mills, pebble mills, roller mills, attritors and colloid mills. A sand grinder mill and a high-speed impeller mill are particularly preferred. Further, preliminary dispersion processing may be performed. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder.
The inorganic fine particle dispersion is preferably made as fine as possible in the dispersion medium, and has a mass average diameter of 1 to 200 nm. Preferably it is 5-150 nm, More preferably, it is 10-100 nm, Most preferably, it is 10-80 nm.
By refining the inorganic fine particles to 200 nm or less, a high refractive index layer that does not impair the transparency can be formed.

  The high-refractive index layer used in the present invention is preferably a dispersion containing inorganic fine particles dispersed in a dispersion medium as described above, preferably a binder precursor necessary for matrix formation (the above-mentioned antiglare hard coat layer and The same), a photopolymerization initiator or the like to form a coating composition for forming a high refractive index layer, and a coating composition for forming a high refractive index layer on a transparent support, It is preferably formed by curing by a crosslinking reaction or a polymerization reaction (for example, a polyfunctional monomer or a polyfunctional oligomer).

  It is preferable to use a photopolymerization initiator for the polymerization reaction of the photopolymerizable polyfunctional monomer. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable. As the radical photopolymerization initiator, the same one as the above-mentioned antiglare hard coat layer is used.

In the high refractive index layer, the binder preferably further has a silanol group. When the binder further has a silanol group, the physical strength, chemical resistance, and weather resistance of the high refractive index layer are further improved.
For example, the silanol group is a compound represented by the general formula (1) having a crosslinkable or polymerizable functional group, which is added to the coating composition for forming the high refractive index layer, and the coating composition is placed on the transparent support. The dispersant, the polyfunctional monomer, the polyfunctional oligomer, and the compound represented by the general formula (1) can be introduced into the binder by crosslinking reaction or polymerization reaction.

  In the high refractive index layer, the binder preferably has an amino group or a quaternary ammonium group. A monomer having an amino group or a quaternary ammonium group maintains good dispersibility of the inorganic fine particles in the high refractive index layer, and can produce a high refractive index layer excellent in physical strength, chemical resistance, and weather resistance. .

  The crosslinked or polymerized binder has a structure in which the main chain of the polymer is crosslinked or polymerized. Examples of the polymer main chain include polyolefin (saturated hydrocarbon), polyether, polyurea, polyurethane, polyester, polyamine, polyamide and melamine resin. A polyolefin main chain, a polyether main chain and a polyurea main chain are preferable, a polyolefin main chain and a polyether main chain are more preferable, and a polyolefin main chain is most preferable.

The binder is preferably a copolymer having a repeating unit having an anionic group and a repeating unit having a crosslinked or polymerized structure. The proportion of the repeating unit having an anionic group in the copolymer is preferably 2 to 96 mol%, more preferably 4 to 94 mol%, and most preferably 6 to 92 mol%. The repeating unit may have two or more anionic groups. The proportion of the repeating unit having a crosslinked or polymerized structure in the copolymer is preferably 4 to 98 mol%, more preferably 6 to 96 mol%, and most preferably 8 to 94 mol%.

The high refractive index layer can contain fine inorganic fine particles in addition to the inorganic fine particles mainly composed of titanium dioxide. As the other inorganic fine particles, the inorganic fine particles contained in the antiglare hard coat layer may be used, and are preferably finely dispersed. The preferable post-dispersion particle size and primary particle size are the antiglare property. As described in the column of the hard coat layer.
The content of the inorganic fine particles in the high refractive index layer is preferably 10 to 90% by mass, more preferably 15 to 80% by mass, and particularly preferably 15 to 75% by mass with respect to the mass of the high refractive index layer. . Two or more inorganic fine particles may be used in combination in the high refractive index layer.
When the low refractive index layer is provided on the high refractive index layer, the refractive index of the high refractive index layer is preferably higher than the refractive index of the transparent support.
The high refractive index layer contains an ionizing radiation curable compound containing an aromatic ring, an ionizing radiation curable compound containing a halogenated element other than fluorine (for example, Br, I, Cl, etc.), and atoms such as S, N, P, etc. Binders obtained by crosslinking or polymerization reaction such as ionizing radiation curable compounds can also be preferably used.
In order to construct an antireflection film by constructing a low refractive index layer on a high refractive index layer, the refractive index of the high refractive index layer is preferably 1.55 to 2.40, more preferably 1.60 to 2.20, more preferably 1.65 to 2.10, and most preferably 1.80 to 2.00.

In addition to the above components (inorganic fine particles, polymerization initiators, photosensitizers, etc.), the high refractive index layer includes resins, surfactants, antistatic agents, coupling agents, thickeners, anti-coloring agents, and coloring. Agents (pigments, dyes), anti-glare imparting particles, antifoaming agents, leveling agents, flame retardants, ultraviolet absorbers, infrared absorbers, adhesion promoters, polymerization inhibitors, antioxidants, surface modifiers, conductivity It is also possible to add metal fine particles.
The film thickness of the high refractive index layer can be appropriately designed depending on the application. When using a high refractive index layer as said light-diffusion layer, 30-200 nm is preferable, More preferably, it is 50-170 nm, Most preferably, it is 60-150 nm.

  In the formation of the high refractive index layer, the crosslinking reaction or the polymerization reaction of the ionizing radiation curable compound is performed with an oxygen concentration of 10% by volume or less, preferably an oxygen concentration of 6% by volume or less, particularly preferably an oxygen concentration of 2% by volume. Hereinafter, it is most preferable to carry out in an atmosphere of 1% by volume or less.

[Low refractive index layer]
The low refractive index layer is an essential layer of the antireflection film, and the refractive index of the low refractive index layer is preferably 1.20 to 1.49, more preferably 1.30 to 1.44. Is in range.
Further, the low refractive index layer preferably satisfies the following formula (VII) from the viewpoint of reducing the reflectance.
Formula (VII)
(M / 4) × 0.7 <n ₁ d ₁ <(m / 4) × 1.3
In the formula, m is a positive odd number, n ₁ is the refractive index of the low refractive index layer, and d ₁ is the film thickness (nm) of the low refractive index layer. Further, λ is a wavelength, which is a value in the range of 500 to 550 nm.
In addition, satisfy | filling said numerical formula (VII) means that m (positive odd number, usually 1) which satisfy | fills numerical formula (VII) exists in the said wavelength range.

The material for forming the low refractive index layer will be described below.
The low refractive index layer preferably contains a fluorine-containing polymer as a low refractive index binder. The fluorine-containing polymer is preferably a fluorine-containing polymer that is crosslinked by heat or ionizing radiation having a dynamic friction coefficient of 0.03 to 0.15 and a contact angle with water of 90 to 120 °. As described above, an inorganic filler for improving the film strength can also be used.

  Examples of the fluorine-containing polymer used in the low refractive index layer include hydrolysis and dehydration condensate of perfluoroalkyl group-containing silane compounds [for example, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane]. And a fluorine-containing copolymer having a fluorine-containing monomer unit and a structural unit for imparting crosslinking reactivity as structural components.

  Specific examples of the fluorine-containing monomer unit include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, perfluorooctylethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole. Etc.), partially (meth) acrylic acid or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemical), M-2020 (manufactured by Daikin), etc.), fully or partially fluorinated vinyl ethers, etc. However, perfluoroolefins are preferred, and hexafluoropropylene is particularly preferred from the viewpoints of refractive index, solubility, transparency, availability, and the like.

  As structural units for imparting crosslinking reactivity, structural units obtained by polymerization of monomers having a self-crosslinkable functional group in advance in the molecule such as glycidyl (meth) acrylate and glycidyl vinyl ether, carboxyl groups, hydroxy groups, amino groups , Obtained by polymerization of a monomer having a sulfo group or the like (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, maleic acid, crotonic acid, etc.) And a structural unit obtained by introducing a crosslinking reactive group such as a (meth) acryloyl group into these structural units by a polymer reaction (for example, it can be introduced by a technique such as allowing acrylic acid chloride to act on a hydroxy group) And the like.

  In addition to the fluorine-containing monomer unit and the structural unit for imparting crosslinking reactivity, a monomer not containing a fluorine atom can be copolymerized as appropriate from the viewpoints of solubility in a solvent and film transparency. There are no particular limitations on the monomer units that can be used in combination. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, acrylic acid 2) -Ethylhexyl), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, vinyltoluene, α-methylstyrene, etc.), vinyl ethers (methyl) Vinyl ether, ethyl vinyl ether, cyclohexyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate etc.), acrylamides (N-tertbutylacrylamide, N-silane) B hexyl acrylamide), methacrylamides, and acrylonitrile derivatives.

  As described in JP-A-10-25388 and JP-A-10-147739, a curing agent may be appropriately used in combination with the polymer.

  The fluorine-containing polymer particularly useful in the present invention is a random copolymer of perfluoroolefin and vinyl ethers or vinyl esters. In particular, it preferably has a group capable of undergoing a crosslinking reaction alone (a radical reactive group such as a (meth) acryloyl group, a ring-opening polymerizable group such as an epoxy group or an oxetanyl group). These cross-linking reactive group-containing polymer units preferably occupy 5 to 70 mol%, particularly preferably 30 to 60 mol% of the total polymer units of the polymer.

The following general formula (2) is mentioned as a preferable form of the fluorine-containing polymer used in the present invention.

In the general formula (2), L represents a linking group having 1 to 10 carbon atoms, more preferably a linking group having 1 to 6 carbon atoms, particularly preferably a linking group having 2 to 4 carbon atoms, which is linear. Alternatively, it may have a branched structure, may have a ring structure, or may have a heteroatom selected from O, N, and S.
Preferred examples include *-(CH ₂ ) ₂ -O-**, *-(CH ₂ ) ₂ -NH-**, *-(CH ₂ ) ₄ -O-**, *-(CH ₂ ) ₆ -O-**, *-(CH ₂ ) ₂ -O- (CH ₂ ) ₂ -O-**, * -CONH- (CH ₂ ) ₃ -O-**, * -CH ₂ CH (OH ) CH ₂ -O-**, * -CH ₂ CH ₂ OCONH (CH ₂ ) ₃ -O-** (* represents the linking site on the polymer main chain side, ** is the linking on the (meth) acryloyl group side) Represents a part). m represents 0 or 1;

  In general formula (2), X represents a hydrogen atom or a methyl group. From the viewpoint of curing reactivity, a hydrogen atom is more preferable.

  In the general formula (2), A represents a repeating unit derived from an arbitrary vinyl monomer, and is not particularly limited as long as it is a constituent component of a monomer copolymerizable with hexafluoropropylene. The polymer Tg (contributes to film hardness), solubility in solvents, transparency, slipperiness, dustproof / antifouling properties, etc., can be selected as appropriate, depending on the purpose. You may be comprised by the monomer.

  Preferred examples include methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, vinyl ethers such as allyl vinyl ether, vinyl acetate, vinyl propionate, butyric acid. (Meth) such as vinyl esters such as vinyl, methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, allyl (meth) acrylate, (meth) acryloyloxypropyltrimethoxysilane Acrylates, styrene, styrene derivatives such as p-hydroxymethylstyrene, crotonic acid, maleic acid, itaconic acid Can be mentioned unsaturated carboxylic acids and derivatives thereof, more preferably ether derivatives, vinyl ester derivatives, particularly preferably a vinyl ether derivative.

  x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65. Preferably, 35 ≦ x ≦ 55, 30 ≦ y ≦ 60, and 0 ≦ z ≦ 20, and particularly preferably 40 ≦ x ≦ 55, 40 ≦ y ≦ 55, and 0 ≦ z ≦ 10. However, x + y + z = 100.

  The following general formula (3) is mentioned as a more preferable form of the general formula (2) of the fluorine-containing polymer used in the present invention.

In general formula (3), X represents the same meaning as in general formula (2), and the preferred range is also the same.
n represents an integer of 2 ≦ n ≦ 10, preferably 2 ≦ n ≦ 6, and particularly preferably 2 ≦ n ≦ 4.
B represents a unit of a repeating unit derived from an arbitrary vinyl monomer, and may be composed of a single composition or a plurality of compositions. As an example, A in the general formula (2)
This is the case with the examples described above.
x, y, z1 and z2 each represent mol% of each repeating unit, and x and y preferably satisfy 30 ≦ x ≦ 60 and 5 ≦ y ≦ 70, respectively, more preferably 35 ≦ x ≦ 55. 30 ≦ y ≦ 60, particularly preferably 40 ≦ x ≦ 55 and 40 ≦ y ≦ 55. z1 and z2 preferably satisfy 0 ≦ z1 ≦ 65 and 0 ≦ z2 ≦ 65, more preferably 0 ≦ z1 ≦ 30 and 0 ≦ z2 ≦ 10, and 0 ≦ z1 ≦ 10, 0 It is particularly preferable that ≦ z2 ≦ 5. However, x + y + z1 + z2 = 100.

  The polymer represented by the general formula (2) or (3) can be obtained by, for example, introducing a (meth) acryloyl group into a polymer comprising a hexafluoropropylene component and a hydroxyalkyl vinyl ether component by any of the above-described methods. Can be synthesized.

  The composition for forming a low refractive index layer of the present invention preferably contains a fluorine-containing copolymer that is usually in the form of a liquid and contains the above-mentioned fluorine-containing monomer unit as a binder, and various additives as necessary. And a radical polymerization initiator dissolved in a suitable solvent. At this time, the concentration of the solid content is appropriately selected according to the use, but is generally about 0.01 to 60% by mass, preferably 0.5 to 50% by mass, particularly preferably 1% to 20% by mass. %.

  From the viewpoint of film hardness of the low refractive index layer, it is not always advantageous to add an additive such as a curing agent, but from the viewpoint of interfacial adhesion with the high refractive index layer, a polyfunctional (meth) acrylate compound, A small amount of a curing agent such as a polyfunctional epoxy compound, a polyisocyanate compound, an aminoplast, a polybasic acid or an anhydride thereof may be added. When adding these, it is preferable that it is the range of 0-30 mass% with respect to the total solid of a low refractive index layer membrane | film | coat, It is more preferable that it is the range of 0-20 mass%, 0-10 mass % Range is particularly preferred.

  For the purpose of imparting properties such as antifouling properties, water resistance, chemical resistance, and slipping properties, known silicone-based or fluorine-based antifouling agents, slipping agents, and the like can be appropriately added. When these additives are added, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the low refractive index layer, more preferably in the range of 0.05 to 10% by mass. Particularly preferred is 0.1 to 5% by mass.

Preferable examples of the silicone compound include those having a substituent at the terminal and / or side chain of a compound chain containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, fluoroalkyl group, polyoxyalkylene group, carboxyl group, amino group and the like. It is done. Although there is no restriction | limiting in particular in molecular weight, It is preferable that it is 100,000 or less, It is especially preferable that it is 50,000 or less, It is most preferable that it is 3000-30000. Although there is no restriction | limiting in particular in silicone atom content of a silicone type compound, it is preferable that it is 18.0 mass% or more, it is especially preferable that it is 25.0-37.8 mass%, and 30.0-37.0. Most preferably, it is mass%. Examples of preferred silicone compounds include X-22-174DX, X-22-2426, X-22-164B, X22-164C, X-22-170DX, X-22-176D, X, manufactured by Shin-Etsu Chemical Co., Ltd. -22-1821 (named above), Chisso Corporation, FM-0725, FM-7725, DMS-U22, RMS-033, RMS-083, UMS-182 (named above), etc. It is not limited to.

As the fluorine-based compound, a fluoroaliphatic group-containing polymer as the surface modifier and a fluorine-based polymer used as a binder in the low refractive index layer are also preferable, and other compounds having a fluoroalkyl group are also preferable. The fluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and a straight chain (for example, —CF ₂ CF ₃ , —CH ₂ (CF ₂ ) ₄ H, —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ H, etc.), for example, —CH (CF ₃ ) ₂ , —CH ₂ CF (CF ₃ ) ₂ , —CH (CH ₃ ) CF ₂ CF ₃ , —CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.), but alicyclic structures (preferably 5-membered or 6-membered rings such as perfluorocyclohexyl groups) , A perfluorocyclopentyl group or an alkyl group substituted with these, and may have an ether bond (for example, —CH ₂ OCH ₂ CF ₂ CF ₃ , —CH ₂ CH ₂ OCH ₂ C). _{4 F 8 H, -CH 2 CH} 2 OCH 2 CH 2 C 8 F 17, -CH 2 CH 2 OCF 2 CF 2 OCF 2 CF 2 H , etc.). A plurality of the fluoroalkyl groups may be contained in the same molecule.
The fluorine-based compound preferably further has a substituent (for example, an acryloyl group, a methacryloyl group, or an epoxy group) that contributes to bond formation with the low refractive index layer film or compatibility.
The film thickness of the low refractive index layer is preferably 20 to 300 nm, more preferably 40 to 200 nm, and particularly preferably 60 to 150 nm.

  When a polyoxyalkylene compound, a cationic surfactant, and a compound containing these as a constituent unit are added to the low refractive index layer as an additive, the low refractive index layer is completely solid. It is preferably added in the range of 0.01 to 20% by mass, more preferably 0.05 to 10% by mass, and particularly preferably 0.1 to 5% by mass. Is the case. Examples of preferable compounds include, but are not limited to, Dainippon Ink Co., Ltd., MegaFuck F-150 (trade name), Toray Dow Corning Co., Ltd., SH-3748 (trade name), and the like. Do not mean.

[Antistatic layer]
The antireflection film is preferably provided with a transparent antistatic layer having a conductive material for antistatic. A transparent antistatic layer may be newly provided independently, but the antistatic function is achieved by adding a conductive material to the antiglare hard coat layer, light diffusion layer, high refractive index layer, medium refractive index layer, and low refractive index layer. May be given together. In particular, an antistatic layer is preferably provided between the hard coat layer and the transparent support.
The conductive material is preferably formed from fine particles of metal oxide or nitride. Examples of metal oxides or nitrides include tin oxide, indium oxide, zinc oxide and titanium nitride. Among these, tin oxide and indium oxide are particularly preferable, and an oxide or nitride of these metals can be the main component and further other elements can be included. The main component means a component having the largest content (mass%) among the components constituting the particles. Examples of other elements include Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, S, B, Nb, In, V and halogen atoms are included. In order to increase the conductivity of tin oxide and indium oxide, it is preferable to add Sb, P, B, Nb, In, V and a halogen atom. Antimony-tin oxide, indium-tin oxide, and zinc antimonate are preferred.
Other than these, metal fine particles, ionic polymer compounds, polyoxyalkylene compounds, cationic surfactants and the like are also preferably used. The degree of antistatic ability surface resistivity value of the antistatic layer is 10 ¹¹ Ω / □ or less (25 ℃, 60% RH), the more preferable, the haze of the antistatic layer as long ¹⁰ 10 Ω / □ or less 20 % Or less is preferable.

[Transparent support]
A plastic film is preferably used as the transparent support of the antireflection film. Examples of the polymer forming the plastic film include cellulose esters (eg, triacetyl cellulose, diacetyl cellulose, typically TAC-TD80U, TD80UF, etc. manufactured by Fuji Photo Film), polyamide, polycarbonate, polyester (eg, polyethylene terephthalate, polyethylene). Naphthalate), polystyrene, polyolefin, norbornene-based resin (Arton: trade name, manufactured by JSR Corporation), amorphous polyolefin (ZEONEX: trade name, manufactured by Nippon Zeon Corporation), and the like. Of these, triacetyl cellulose, polyethylene terephthalate, and polyethylene naphthalate are preferable, and triacetyl cellulose is particularly preferable.
Triacetyl cellulose consists of a single layer or a plurality of layers. Single-layer triacetyl cellulose is prepared by drum casting or band casting disclosed in JP-A-7-11055, and the latter triacetyl cellulose is a special feature of the published patent publication. It is prepared by the so-called co-casting method disclosed in Japanese Utility Model Publication Nos. 61-94725 and 62-43846.
The thickness of the transparent support is usually about 25 μm to 200 μm.

When triacetyl cellulose is used as a support for an antireflection film, it is not necessary to control retardation, and the retardation control agent may or may not be included.
When used as a support for an antireflection film, it is desirable that the retardation is as small as possible, that is, it has no optical anisotropy, the front retardation is preferably 5 nm or less, and the retardation in the thickness direction is preferably 10 nm. . Furthermore, it is preferable that the front retardation is 3 nm or less and the retardation in the thickness direction is 5 nm.
Moreover, although it is not necessary to control retardation by extending | stretching process, in order to improve the film thickness nonuniformity and surface unevenness which generate | occur | produce by drying nonuniformity and drying shrinkage | contraction, a extending | stretching process can be performed. The specific method of the stretching process is the same as the stretching process of the retardation film.

The antireflection film is used as a protective film for a polarizing plate by providing an adhesive layer on one side. In this case, for sufficient adhesion, it is preferable to carry out a saponification treatment after forming an outermost layer preferably containing a fluorine-containing polymer on a transparent support. The saponification treatment is performed by a known method, for example, by immersing the film in an alkali solution for an appropriate time. After being immersed in the alkali solution, it is preferable to sufficiently wash with water or neutralize the alkali component by immersing in a dilute acid so that the alkali component does not remain in the film.
By the saponification treatment, the surface of the transparent support opposite to the side having the outermost layer is hydrophilized.
The hydrophilized surface is particularly effective for improving the adhesion with a polarizing film containing polyvinyl alcohol as a main component. In addition, the hydrophilic surface makes it difficult for dust in the air to adhere to it, so that it is difficult for dust to enter between the polarizing film and the antireflection film when adhered to the polarizing film, and to prevent point defects due to dust. It is valid.
The saponification treatment is preferably carried out so that the contact angle of water on the surface of the transparent support opposite to the side having the outermost layer is 40 ° or less. More preferably, it is 30 ° or less, particularly preferably 20 ° or less.

Specific examples of the alkali saponification treatment include the following two means (1) and (2). (1) is superior in that it can be processed in the same process as a general-purpose triacetylcellulose film, but since the surface of the antireflection film is saponified, the surface is alkali-hydrolyzed and the film deteriorates. The problem of becoming dirty when the liquid remains can be a problem. In that case, although it becomes a special process, (2) is excellent.
(1) After the antireflection layer is formed on the transparent support, the back surface of the film is saponified by immersing it in an alkaline solution at least once.
(2) Before or after the formation of the antireflection layer on the transparent support, an alkaline solution is applied to the surface of the antireflection film opposite to the surface on which the antireflection film is formed, and is heated, washed and / or washed. By summing, only the back surface of the film is saponified.

The antireflection film can be formed by the following method, but is not limited to this method.
First, a coating solution containing components for forming each layer is prepared.
Next, in the case of providing a hard coat layer, a coating solution for forming the hard coat layer is prepared by a dip coat method, an air knife coat method, a curtain coat method, a roller coat method, a wire bar coat method, a gravure coat method, The coating is applied on the transparent support by the extrusion coating method (see US Pat. No. 2,681,294), heated and dried, and the microgravure coating method is particularly preferred. Thereafter, the monomer for forming the hard coat layer is polymerized and cured by light irradiation or heating. Thereby, a hard coat layer is formed.
Here, if necessary, the hard coat layer may be formed into a plurality of layers, and smooth hard coat layer application and curing can be performed by the same method before application of the antiglare hard coat layer. The antiglare hard coat layer can be formed in the same manner as the hard coat layer.
Next, a coating solution for forming a low refractive index layer is applied on the antiglare hard coat layer in the same manner, and light irradiation or heating is performed to form the low refractive index layer. In this way, one embodiment of the antireflection film is obtained.

  The micro gravure coating method used in the present invention is a gravure roll having a diameter of about 10 to 100 mm, preferably about 20 to 50 mm and engraved with a gravure pattern on the entire circumference, below the support and in the transport direction of the support. The gravure roll is rotated in reverse with respect to the gravure roll, the excess coating liquid is scraped off from the surface of the gravure roll by a doctor blade, and a fixed amount of the coating liquid is removed from the support in a position where the upper surface of the support is in a free state. The coating method is characterized in that the coating liquid is transferred onto the lower surface for coating. A roll-shaped transparent support is continuously unwound, and at least one layer of at least one of a hard coat layer or a low refractive index layer containing a fluorine-containing polymer is provided on one side of the unwound support. Can be applied by.

As coating conditions by the micro gravure coating method, the number of gravure patterns imprinted on the gravure roll is preferably 50 to 800 lines / inch, more preferably 100 to 300 lines / inch, and the depth of the gravure pattern is 1 to 600 μm. Is preferable, 5 to 200 μm is more preferable, the rotation speed of the gravure roll is preferably 3 to 800 rpm, more preferably 5 to 200 rpm, and the conveyance speed of the support is 0.5 to 100 m / min. It is preferably 1 to 50 m / min.
The antireflection film thus formed has a haze value of preferably 3 to 70%, more preferably 4 to 60%, and an average reflectance of 450 nm to 650 nm, preferably 3.0% or less. More preferably, it is 2.5% or less.
When the antireflection film has a haze value and an average reflectance within the above ranges, good antiglare properties and antireflection properties can be obtained without causing deterioration of the transmitted image.
The transmitted image clarity of the antireflection film is 15% to 60%.
It is preferable in that the antiglare property and the black luminance are in desired ranges.
Here, the transmitted image clearness can be measured by the method described in Examples.

In the present invention, the functional film on the other side may be formed by only a functional film made of only the antireflection film, or may be formed by overlapping the film with another functional film. .
Examples of other functional films include a hard coat film and a color filter film.

<Configuration of polarizing plate>
The polarizing plate is usually composed of two functional films sandwiching a polarizing film from both sides. Usually, each functional film is mainly composed of one protective film. The polarizing plate of the present invention has the cellulose acylate film on at least one of two protective films sandwiching the polarizing film from both sides, and the cellulose acylate film opposite to the polarizing film. At least one of
The antireflection film is used as a sheet.
Since the cellulose acylate film and the antireflection film also serve as a protective film, the production cost of the polarizing plate can be reduced. Further, by using the antireflection film on the outermost surface of the polarizing plate, reflection of external light and the like can be prevented, and a polarizing plate having excellent scratch resistance, antifouling property and the like can be obtained. That is, the preferred structure of the polarizing plate of the present invention is a polarizing film, a functional film made of a cellulose acylate film laminated on one side of the polarizing film, and an antireflection laminated on the other side of the polarizing film. This is a functional film made of a film, and has a structure in which the surface on one side of the polarizing plate is formed of a cellulose acylate film and the surface on the other side is formed of an antireflection film.
As the polarizing film, a known polarizing film or a polarizing film cut out from a long polarizing film whose absorption axis is neither parallel nor perpendicular to the longitudinal direction may be used.
The method for stretching the polymer film is described in detail in paragraphs 0020 to 0030 of JP-A-2002-86554.
The polarizing plate of the present invention can be applied to an image display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence display (ELD), or a cathode ray tube display device (CRT). Since the polarizing plate of the present invention has a transparent support, the transparent support side is adhered to the image display surface of the image display device. And it is preferable that the polarizing plate of this invention is used for the outermost surface of a liquid crystal display device.

  The polarizing plate of the present invention is capable of transmitting modes such as twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), and optically compensated bend cell (OCB). It can be preferably used for a liquid crystal display device of a type, a reflection type, or a transflective type. In particular, the liquid crystal display device of the present invention is preferably in the TN mode or the VA mode.

  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-). (2) In addition to (2) Liquid crystal cell (SID97, Digest of tech. Papers (Preliminary Collection) 28 (1997) 845 in which VA mode is multi-domained (MVA mode) for viewing angle expansion ), (3) Liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (1998)) and (4) SURVAVAL mode liquid crystal cells (announced at LCD International 98).

  The OCB mode liquid crystal cell is a liquid crystal display device using a bend alignment mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned in a substantially opposite direction (symmetrically) between the upper part and the lower part of the liquid crystal cell. It is disclosed in the specifications of Japanese Patent Nos. 45882525 and 5410422. Since the rod-like liquid crystal molecules are symmetrically aligned at the upper and lower portions of the liquid crystal cell, the bend alignment mode liquid crystal cell has a self-optical compensation function. Therefore, this liquid crystal mode is also called an OCB (Optically Compensatory Bend) liquid crystal mode. The bend alignment mode liquid crystal display device has an advantage of high response speed.

  In an ECB mode liquid crystal cell, rod-like liquid crystal molecules are substantially horizontally aligned when no voltage is applied, and is most frequently used as a color TFT liquid crystal display device, and is described in many documents. For example, it is described in “EL, PDP, LCD display” published by Toray Research Center (2001).

In order to describe the present invention in detail, examples will be described below, but the present invention is not limited thereto. Unless otherwise specified, “part” and “%” are based on mass.

  (Synthesis of the following perfluoroolefin copolymer (1))

Into a stainless steel autoclave with a stirrer of 100 ml, 40 ml of ethyl acetate, 14.7 g of hydroxyethyl vinyl ether and 0.55 g of dilauroyl peroxide were charged, and the inside of the system was deaerated and replaced with nitrogen gas. Furthermore, 25 g of hexafluoropropylene (HFP) was introduced into the autoclave and the temperature was raised to 65 ° C. The pressure when the temperature in the autoclave reached 65 ° C. was 5.4 kg / cm ² . The reaction was continued for 8 hours while maintaining the temperature, and when the pressure reached 3.2 kg / cm ² , the heating was stopped and the mixture was allowed to cool. When the internal temperature dropped to room temperature, unreacted monomers were driven out, the autoclave was opened, and the reaction solution was taken out. The obtained reaction solution was poured into a large excess of hexane, and the polymer was precipitated by removing the solvent by decantation. Further, this polymer was dissolved in a small amount of ethyl acetate and reprecipitated twice from hexane to completely remove the residual monomer. After drying, 28 g of polymer was obtained.
Next, 20 g of the polymer was dissolved in 100 ml of N, N-dimethylacetamide, and 11.4 g of acrylic acid chloride was added dropwise under ice cooling, followed by stirring at room temperature for 10 hours. Ethyl acetate was added to the reaction solution, washed with water, the organic layer was extracted and concentrated, and the resulting polymer was reprecipitated with hexane to obtain 19 g of perfluoroolefin copolymer (1). The resulting polymer had a refractive index of 1.421.

(Synthesis of fluorine-based surface modifier P-8)
In a reactor equipped with a stirrer and a reflux condenser, 39.93 g of 1H, 1H, 7H-dodecafluoroheptyl acrylate, 1.1 g of dimethyl 2,2′-azobisisobutyrate and 30 g of 2-butanone were added, and the atmosphere was nitrogen. For 6 hours at 78 ° C. to complete the reaction. The mass average molecular weight was 2.9 × 10 ⁴ .

(Preparation of sol solution a)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), 3 parts of diisopropoxyaluminum ethyl acetoacetate were added and mixed. After that, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol solution a. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of antistatic layer coating solution-1 for forming a hard coat layer having antistatic properties)
To a mixed liquid of 190 g of ethanol and 82 g of methyl ethyl ketone, 176 g of an antimony-doped tin oxide dispersion described later was added. To this was added 2.4 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), and a polymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.). 0.3 g was added and mixed and stirred. An antistatic layer coating solution-1 was prepared by immersing an oscillation chip in this solution and applying ultrasonic dispersion for 10 minutes.
The obtained antistatic layer coating solution-1 was applied to a triacetylcellulose film having a thickness of 80 μm (the haze of the film alone was 0.2%) by the method described in the coating of the internal constituent layer described later. The haze of this sample was 2.8%. The surface specific resistance value of this sample was measured by a circular electrode method and found to be 1.8 × 10 ¹⁰ Ω / □ (25 ° C., 60% RH).
(Preparation of antimony-doped tin oxide dispersion)
To a mixed liquid obtained by adding 132 g of ethanol and 3 g of a carboxylic acid group-containing acrylic polymer to 15 g of antimony-doped tin oxide fine particle powder (SN-100P manufactured by Ishihara Techno Co., Ltd.), 150 g of 1 mmφ glass beads were added and placed in a pressure bottle. Dispersed for 50 hours in a paint shaker. The average particle size was 85 nm.

(Preparation of coating solution A for antiglare hard coat layer)
50 g of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (PETA, Nippon Kayaku Co., Ltd.) was diluted with 38.5 g of toluene. Furthermore, 2 g of a polymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) was added and mixed and stirred. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet rays was 1.51.
Further, a 30% toluene dispersion of crosslinked polystyrene particles having an average particle size of 3.5 μm (refractive index 1.61, SX-350, manufactured by Soken Chemical Co., Ltd.) dispersed in this solution for 20 minutes at 10,000 rpm with a Polytron disperser. Add 13.3 g of 30% toluene dispersion of crosslinked acrylic-styrene particles (refractive index 1.55, manufactured by Soken Chemical Co., Ltd.) having 1.7 g and an average particle size of 3.5 μm, and finally, the fluorine-based surface 0.75 g of modifier (P-8) and 10 g of silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.) were added to obtain a mixed solution.
The mixed solution was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating solution A for an antiglare hard coat layer.
The surface tension before adding the fluorine-based surface modifier (P-8) to this coating liquid A was 35 mN / m, and the surface tension after the addition was 32 mN / m.

(Preparation of coating solution B for antiglare hard coat layer)
The antiglare hard coat is the same as the coating liquid A except that the fluorine surface modifier (P-8) of the coating liquid A for the antiglare hard coat layer is changed to (P-13). Layer coating solution B was prepared.
The surface tension before adding the fluorine-based surface modifier (P-13) to this coating liquid B was 35 mN / m, and the surface tension after the addition was 30 mN / m.

(Preparation of coating solution C for antiglare hard coat layer)
Coating for anti-glare hard coat layer is the same as coating liquid A except that the particle size of the crosslinked polystyrene and crosslinked acrylic-styrene particles in coating liquid A for anti-glare hard coat layer is both changed to 4.5 μm. Liquid C was prepared.
The surface tension before adding the fluorine-based surface modifier (P-13) to this coating liquid C was 35 mN / m, and the surface tension after the addition was 30 mN / m.

(Preparation of coating solution D for antiglare hard coat layer)
Coating for anti-glare hard coat layer is the same as coating liquid A except that the particle size of the crosslinked polystyrene and crosslinked acrylic-styrene particles in coating liquid A for anti-glare hard coat layer is both changed to 2.5 μm. Liquid D was prepared.
The surface tension before adding the fluorine-based surface modifier (P-13) to this coating liquid D was 35 mN / m, and the surface tension after the addition was 30 mN / m.

(Preparation of coating solution B for light diffusion layer)
285 g of commercially available zirconia-containing UV curable hard coat liquid (Desolite Z7404, manufactured by JSR Corporation, solid content concentration of about 61%, ZrO ₂ content of solid content of about 70%, polymerizable monomer, polymerization initiator contained), dipenta 85 g of a mixture of erythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) was mixed, and further diluted with 60 g of methyl isobutyl ketone and 17 g of methyl ethyl ketone. Furthermore, 28 g of a silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed and stirred. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet rays was 1.61, satisfying the conditions of the high refractive index layer in the present invention.
Further, a 30% methyl isobutyl ketone dispersion of classified strengthened crosslinked PMMA particles (refractive index: 1.49, MXS-300, manufactured by Soken Chemical Co., Ltd.) having an average particle size of 3.0 μm was added to this solution at 10,000 rpm with a Polytron disperser. 35 g of a dispersion dispersed for 20 minutes was added, and then a 30% methyl ethyl ketone dispersion of silica particles having an average particle diameter of 1.5 μm (refractive index 1.46, Seahosta KE-P150, manufactured by Nippon Shokubai Co., Ltd.) 90 g of the dispersion liquid dispersed at 10,000 rpm for 30 minutes was added, and finally 0.12 g of the fluorine-based surface modifier (P-8) was mixed and stirred to obtain a finished liquid.
The mixed solution was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare a coating solution B for a light diffusion layer.

(Preparation of coating solution C for light diffusion layer)
In the light diffusion layer coating solution B, instead of silica particles having an average particle size of 1.5 μm, classified highly-crosslinked PMMA particles having an average particle size of 1.5 μm (MXS-150H, cross-linking agent ethylene glycol dimethacrylate, amount of cross-linking agent 30 %, A coating solution C for light diffusing layer was prepared in the same manner as the coating liquid A, including the addition amount, except that 130 g of 30% methyl ethyl ketone dispersion liquid manufactured by Soken Chemical Co., Ltd., refractive index 1.49) was used. .
The refractive index of the coating film obtained by applying this solution and curing with ultraviolet rays was 1.61, satisfying the conditions of the high refractive index layer in the present invention.

(Preparation of coating solution A for low refractive index layer)
Thermally crosslinkable fluorine-containing polymer having a refractive index of 1.42 (JN7228A, solid content concentration 6%, manufactured by JSR Corporation) 15 g, silica sol (silica, MEK-ST, average particle size 15 nm, solid content concentration 30%, Nissan Chemical) 0.6 g, silica sol (silica, MEK-ST particle size difference, average particle size 45 nm, solid content concentration 30%, manufactured by Nissan Chemical Industries, Ltd.) 0.8 g, sol a 0.4 g, methyl ethyl ketone 3 g and 0.6 g of cyclohexano were added, and after stirring, the mixture was filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution A for a low refractive index layer.

(Preparation of coating solution B for low refractive index layer)
15.2 g of perfluoroolefin copolymer (1), 1.4 g of silica sol (silica, MEK-ST particle size difference product, average particle size 45 nm, solid content concentration 30%, manufactured by Nissan Chemical Industries, Ltd.), reactivity Silicone X-22-164B (trade name; manufactured by Shin-Etsu Chemical Co., Ltd.) 0.3 g, sol solution a 7.3 g, photopolymerization initiator (Irgacure 907 (trade name), manufactured by Ciba Geigy) 0.76 g, methyl ethyl ketone 301 g, After adding 9.0 g of cyclohexanone and stirring, it was filtered through a polypropylene filter having a pore size of 5 μm to prepare a coating solution B for a low refractive index layer.

(Adjustment of coating liquid C for low refractive index layer)
In the coating liquid B for the low refractive index layer, 19.5 g of hollow silica sol (refractive index 1.31, average particle size 60 nm, solid content concentration 20%) was used instead of silica sol, and the perfluoroolefin copolymer (1) 11.7 g and the amount of methyl ethyl ketone was changed to 280 g, and the coating liquid C for low refractive index layer was prepared in the same manner as the coating liquid B including the added amount.

[Production Example 1: Saponified antireflection film samples 101 to 109 used in the present invention]
(1) Coating of internal structure layer A triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd., transparent support) having a thickness of 80 μm was unwound in the form of a roll, and as shown in Table 1, A microgravure roll having a diameter of 50 mm and a doctor blade having a gravure pattern of 180 lines / inch and a depth of 40 μm for the coating liquid for each internal component layer (antistatic layer, antiglare hard coat layer, light diffusion layer) Then, after applying at a gravure roll rotational speed of 30 rpm and a conveying speed of 30 m / min, drying at 60 ° C. for 150 seconds, and further applying a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge. used, illuminance 400 mW / cm ^2, and an irradiation dose of 250 mJ / cm ² to cure the coating layer, form an internal structure layer having a thickness of 6μm Then, it was wound up.
In addition, it coated so that an antistatic layer, an anti-glare hard-coat layer, and a light-diffusion layer might be formed in order from the transparent support side.

(2) Coating of low refractive index layer Next, the triacetyl cellulose film coated with the inner layer was unwound again, and the coating liquid for the low refractive index layer was 180 lines / inch as shown in Table 1. Using a gravure roll with a depth of 40 μm and a microgravure roll with a diameter of 50 mm and a doctor blade, it was applied under the conditions of a gravure roll rotation speed of 30 rpm and a conveyance speed of 15 m / min, dried at 120 ° C. for 150 seconds, and further 140 ° C. After drying for 8 minutes, using an air-cooled metal halide lamp (made by Eye Graphics Co., Ltd.) of 240 W / cm under a nitrogen purge, the film was irradiated with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 900 mJ / cm ^2. A low refractive index layer having a thickness of 100 nm was formed and wound up.
The combination of each coating layer was performed as shown in Table 1.

(Saponification treatment of antireflection film)
The samples 101 to 109 after coating were subjected to the following treatment.
A 1.5 mol / L aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.005 mol / L dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The prepared antireflection film was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C.
In this way, saponified antireflection film samples 101 to 109 were obtained.

[Production Example 2: Saponified antireflection film samples 201 to 204 used in the present invention]
(Preparation of coating liquid A for hard coat layer)
A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.) (315.0 g), silica fine particle methyl ethyl ketone dispersion (MEK-ST, solid concentration 30 mass%, Nissan Chemical ( 450.0 g, 15.0 g of methyl ethyl ketone, 220.0 g of cyclohexanone and 16.0 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy Japan, Inc.) were added and stirred. A coating solution A for a hard coat layer was prepared by filtering through a polypropylene filter having a pore size of 0.4 μm.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129, manufactured by Ishihara Sangyo Co., Ltd.) containing cobalt and surface-treated with aluminum hydroxide and zirconium hydroxide were used.
The following dispersant (38.6 g) and cyclohexanone (704.3 g) were added to 257.1 g of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a mass average diameter of 70 nm.
Dispersant

(Preparation of coating liquid A for medium refractive index layer)
To 88.9 g of the titanium dioxide dispersion, 58.4 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA), 3.1 g of a photopolymerization initiator (Irgacure 907), a photosensitizer (Kayacure DETX) 1.1 g of Nippon Kayaku Co., Ltd.), 482.4 g of methyl ethyl ketone and 1869.8 g of cyclohexanone were added and stirred. Finally, 0.5 g of a fluorine-based surface modifier (P-8) was added and stirred sufficiently, followed by filtration through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution A for a medium refractive index layer.

(Preparation of coating liquid A for high refractive index layer)
To 586.8 g of the titanium dioxide dispersion, 47.9 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), photopolymerization initiator (Irgacure 907, Nippon Ciba Geigy ( 4.0 g), photosensitizer (Kayacure-DETX, Nippon Kayaku Co., Ltd.) 1.3 g, methyl ethyl ketone 455.8 g, and cyclohexanone 1427.8 g were added and stirred. Finally, 0.5 g of a fluorine-based surface modifier (P-8) was added and stirred sufficiently, followed by filtration through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution A for a high refractive index layer.

(Preparation of coating solution D for low refractive index layer)
Thermally crosslinkable fluorine-containing polymer having a refractive index of 1.42 (JN7228A, solid content concentration 6%, manufactured by JSR Corporation) 9 g, silica sol (silica, MEK-ST with different particle size, average particle size 45 nm, solid content concentration 30%, manufactured by Nissan Chemical Industries, Ltd.) 1.4 g, sol solution 0.4 g, methyl isobutyl ketone 3 g, and cyclohexanone 0.6 g were added, stirred, and filtered through a polypropylene filter having a pore size of 1 μm. A refractive index layer coating solution D was prepared.

(Preparation of coating liquid E for low refractive index layer)
A coating liquid E for low refractive index layer was prepared in the same formulation as the coating liquid B for low refractive index layer of Production Example 1.
(Adjustment of coating liquid F for low refractive index layer)
A low refractive index layer coating solution F was prepared in the same formulation as the low refractive index layer coating solution C of Production Example 1.

(Preparation of antireflection film)
A coating solution for an antistatic layer was applied on a triacetyl cellulose film (TD-80UF, manufactured by Fuji Photo Film Co., Ltd., transparent support) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^2. An ultraviolet ray having an irradiation amount of 300 mJ / cm ² was irradiated to cure the coating layer to form an antistatic layer having a thickness of 0.7 μm.
On the antistatic layer, a hard coat layer coating solution was applied using a gravure coater. Drying conditions and ultraviolet irradiation conditions were the same as those of the antistatic layer, and a hard coat layer having a thickness of 3.5 μm was formed.
On the hard coat layer, a medium refractive index layer coating solution was applied using a gravure coater. After drying at 100 ° C., an illuminance of 550 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 240 W / cm while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. ^2. An ultraviolet ray with an irradiation amount of 600 mJ / cm ² was irradiated to cure the coating layer to form a medium refractive index layer (refractive index 1.65, film thickness 67 nm).

  A coating solution for a high refractive index layer was applied on the middle refractive index layer using a gravure coater. Drying conditions and ultraviolet irradiation conditions were the same as those for the high refractive index layer to form a high refractive index layer (refractive index 1.93, film thickness 107 nm).

A low refractive index layer coating solution is applied onto the high refractive index layer using a gravure coater, dried at 120 ° C. for 150 seconds, further dried at 140 ° C. for 8 minutes, and then 240 W / cm under a nitrogen purge. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) and irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 900 mJ / cm ² , and a low refractive index layer (refractive index 1.43, film thickness 86 nm) Formed.
The combination of each layer was performed as shown in Table 2, and antireflection film samples 201 to 204 were produced. As the coating solution for the antistatic layer, the one used in Production Example 1 was used.

(Saponification treatment of antireflection film)
The samples 201 to 204 after coating were subjected to the same saponification treatment as in Production Example 1 to prepare saponified antireflection film samples 201 to 204.

[Production Example 3: Cellulose Acetate Film with Optical Compensation Function Used in the Present Invention]
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 having an acetylation degree of 60.9% 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 300 parts by weight Methanol (No. 1) 2 solvents) 54 parts by mass 1-butanol (third solvent) 11 parts by mass

  Into another mixing tank, 16 parts by mass of the aromatic compound (65), 80 parts by mass of methylene chloride and 20 parts by mass of methanol are added as a retardation increasing agent, and stirred while heating to prepare a retardation increasing agent solution. did. 25 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 3, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 3.5 parts by mass with respect to 100 parts by mass of cellulose acetate.

  The obtained dope was cast using a band casting machine. A film having a residual solvent amount of 15% by mass was horizontally stretched at a stretch ratio of 25% using a tenter under the conditions of 130 ° C. to produce a cellulose acetate film (thickness: 80 μm). About the produced cellulose acetate film with an optical compensation function, the Re retardation value and Rth retardation value in wavelength 550nm were measured using the ellipsometer (M-150, JASCO Corporation make). The results are shown in Table 3.

[Production Example 4: Cellulose Acetate Film with Optical Compensation Function Used in the Present Invention]
The dope was prepared by mixing 474 parts by mass of the cellulose acetate solution with 56 parts by mass of the same retardation increasing agent solution as in Production Example 3 (using 7.8 parts by mass of the retardation increasing agent for 100 parts by mass of cellulose acetate). ) A cellulose acetate film with an optical compensation function was prepared and evaluated in the same manner as in Production Example 3 except that the draw ratio was changed to 14%.
The results are shown in Table 3.

[Production Example 5: Cellulose acetate film with optical compensation function used in the present invention]
Into the mixing tank, 16 parts by mass of the aromatic compound (12) as a rod-like compound as a retardation increasing agent, 87 parts by mass of methylene chloride and 13 parts by mass of methanol are added and stirred while heating to form a retardation increasing agent solution. Was prepared. 36 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 4, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 5.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  The obtained dope was cast using a band casting machine. A cellulose acetate film (thickness: 80 μm) was produced by transverse stretching in the same manner as in Production Example 3 except that the draw ratio was 28%. About the produced cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were measured in the same manner as in Production Example 3. The results are shown in Table 3.

[Production Example R1: Cellulose acetate film with optical compensation function for comparison]
A cellulose acetate film with an optical compensation function was produced and evaluated in the same manner as in Production Example 3 except that the cellulose acetate solution was used as it was as a dope and no stretching treatment was performed. The results are shown in Table 3.

  From the results shown in the above table, it can be seen that the samples of Production Examples 3 to 5 used in the present invention have a Re value Rth value larger than that of Production Example R1 without the letter deshawn increasing agent and without stretching.

[Production Example 6: Cellulose acetate film with optical compensation function used in the present invention]
Each component of the following cellulose acetate solution 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 having an acetylation degree of 60.9% 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 318 parts by weight Methanol (No. 1) 2 solvents) 47 parts by mass

Into another mixing tank, 16 parts by weight of an aromatic compound (46) as a rod-like compound as a retardation increasing agent, 87 parts by weight of methylene chloride and 13 parts by weight of methanol were added and stirred while heating to increase the retardation. An agent solution was prepared.
A dope was prepared by mixing 36 parts by mass of the retardation increasing agent solution with 474 parts by mass of the cellulose acetate solution and stirring sufficiently. The addition amount of the retardation increasing agent was 5.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  The obtained dope was cast using a band casting machine. A film having a residual solvent amount of 15% by mass was laterally stretched at a stretching ratio of 28% using a tenter under the conditions of 130 ° C. to produce a cellulose acetate film (thickness: 82 μm). About the produced cellulose acetate film with an optical compensation function, Re retardation value and Rth retardation value in wavelength 590nm were measured using KOBRA 21ADH (Oji Scientific Instruments Co., Ltd. product). The results are shown in Table 4.

[Production Example 7: Cellulose acetate film with optical compensation function used in the present invention]
Each component of the following additive solution composition was put into a mixing tank, stirred while heating to dissolve each component, and an additive solution in which a further additive was added to the retardation increasing agent was prepared.
(Additional solution composition)
Retardation raising agent used in Production Example 16 16 parts by weight Trimethyl trimellitate 1 part by weight Methylene chloride (first solvent) 87 parts by weight Methanol (second solvent) 13 parts by weight

  44 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 6.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  In the same manner as in Production Example 6, a laterally stretched cellulose acetate film was produced. About the produced cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 8: Cellulose acetate film with optical compensation function used in the present invention]
A mixing tank is charged with 16 parts by weight of an aromatic compound (67) as a rod-like compound as a retardation increasing agent, 87 parts by weight of methylene chloride and 13 parts by weight of methanol, and stirred while heating to form a retardation increasing agent solution. Was prepared.
36 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 5.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  After stripping off the band with a residual solvent amount of 33% and introducing it into a tenter stretching machine, the film was stretched at a stretching ratio of 28%. The film thickness after stretching was 95 μm. After stretching, the film detached from the tenter was dried with hot air at 140 ° C. to prepare a cellulose acetate film with a residual solvent amount of 1% or less. About the produced cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 9: Cellulose acetate film with optical compensation function used in the present invention]
Into the mixing tank, 16 parts by mass of the same retardation increasing agent as in Production Example 6, 3 parts by mass of Sumisorb 165F (manufactured by Sumitomo Chemical Co., Ltd.), 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and heated. While stirring, a retardation increasing agent solution was prepared.
36 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 5.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  After stripping off the band with a residual solvent amount of 33% and introducing it into a tenter stretching machine, the film was stretched at a stretching ratio of 28%. The film thickness after stretching was 95 μm. After stretching, the film detached from the tenter was dried with hot air at 140 ° C. to prepare a cellulose acetate film with a residual solvent amount of 1% or less. About the produced cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 10: Cellulose Acetate Film with Optical Compensation Function Used in the Present Invention]
In the mixing tank, 16 parts by mass of the retardation increasing agent as in Production Example 8, 1.2 parts by mass of UV absorber B (manufactured by TINUVIN327 Ciba Specialty Chemicals), UV absorber C (manufactured by TINUVIN328 Ciba Specialty Chemicals) 2.4 parts by mass, 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and stirred while heating to prepare a retardation increasing agent solution.
36 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 5.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  A cellulose acetate film was produced in the same manner as in Production Example 9. About the produced cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 11: Cellulose acetate film with optical compensation function used in the present invention]
Each component of the following cellulose acylate solution composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution.

(Cellulose acylate solution composition)
Cellulose acetate propionate with an acetyl group substitution degree of 1.90 and a propionyl group substitution degree of 0.80 100 parts by weight Triphenyl phosphate 8.5 parts by weight Ethylphthalyl ethyl glycolate 2.0 parts by weight Methylene chloride 290 parts by weight 60 parts by mass of ethanol

In another mixing tank, 5 parts by mass of acetate propionate, 6 parts by mass of TINUVIN 326 (manufactured by Ciba Specialty Chemicals), 4 parts by mass of TINUVIN 109 (manufactured by Ciba Specialty Chemicals), TINUVIN 171 94 parts by mass of methylene chloride and 8 parts by mass of ethanol were added to 5 parts by mass (manufactured by Ciba Specialty Chemicals Co., Ltd.) and stirred while heating to prepare an additive solution.
10 parts by mass of the additive solution was mixed with 474 parts by mass of the cellulose acylate solution, and the dope was prepared by sufficiently stirring.

  A cellulose acetate propionate film that was horizontally stretched was produced in the same manner as in Production Example 6 except that the stretch ratio was 30% and the film thickness was 80 μm. About the produced cellulose acetate propionate film (optical compensation sheet), the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 12: Cellulose acetate film with optical compensation function used in the present invention]
Into the mixing tank, 16 parts by mass of the retardation increasing agent of Production Example 3, 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added and stirred while heating to prepare a retardation increasing agent solution.
36 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 5.0 parts by mass with respect to 100 parts by mass of cellulose acetate.

  A laterally stretched cellulose acetate film (thickness: 80 μm) was produced in the same manner as in Production Example 6 except that the stretch ratio was 28%. About the produced cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 13: Cellulose acetate film with optical compensation function used in the present invention]
Into the mixing tank, 16 parts by mass of the aromatic compound (66), 87 parts by mass of methylene chloride and 13 parts by mass of methanol were added as a retardation increasing agent, and stirred while heating to prepare a retardation increasing agent solution.
30 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 4.2 parts by mass with respect to 100 parts by mass of cellulose acetate.

  After casting on a band, it was peeled off with a residual solvent amount of 32%, and then stretched in a transverse direction with a tenter stretching machine. The draw ratio was 30%, and the draw temperature was 110 ° C. Thereafter, it was dried with warm air of 130 ° C. to prepare a cellulose acetate film. The film thickness after drying was 96 μm. About the obtained cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 14: Cellulose acetate film with optical compensation function used in the present invention]
After casting on a band using the dope prepared in Production Example 6, the film was peeled off at a residual solvent amount of 32%, and then stretched laterally with a tenter stretching machine. The draw ratio was 26%, and the draw temperature was 130 ° C. Thereafter, it was dried with warm air of 130 ° C. to prepare a cellulose acetate film. Further, the dope flow rate was adjusted so that the film thickness after drying was 92 μm. About the obtained cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 6. The results are shown in Table 4.

[Production Example 15: Cellulose acetate film with optical compensation function used in the present invention]
Into the mixing tank, 16 parts by mass of the retardation increasing agent of Production Example 13, 3 parts by mass of UV absorber A (Sumitomo 165F), 87 parts by mass of methylene chloride, and 13 parts by mass of methanol are charged and heated. Stirring to prepare a retardation increasing agent solution.
30 parts by mass of the retardation increasing agent solution was mixed with 474 parts by mass of the cellulose acetate solution of Production Example 6, and the dope was prepared by sufficiently stirring. The addition amount of the retardation increasing agent was 4.2 parts by mass with respect to 100 parts by mass of cellulose acetate.

  After casting on a band, it was peeled off with a residual solvent amount of 32%, and then stretched in a transverse direction with a tenter stretching machine. The draw ratio was 30%, and the draw temperature was 110 ° C. Thereafter, it was dried with warm air of 130 ° C. to prepare a cellulose acetate film. The film thickness after drying was 96 μm. About the obtained cellulose acetate film with an optical compensation function, the Re retardation value and the Rth retardation value were evaluated in the same manner as in Production Example 1. The results are shown in Table 4.

[Example 1: Polarizing plate of the present invention]
A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film. The cellulose acetate film produced in Production Example 3 was saponified and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. The antireflection film sample 101 of the present invention was saponified and attached to the opposite side of the polarizing film using a polyvinyl alcohol-based adhesive. The transmission axis of the polarizing film and the slow axis of the cellulose acetate film prepared in Production Example 3 were arranged in parallel. The transmission axis of the polarizing film and the slow axis of the cellulose triacetate film of the antireflection film sample 101 were arranged so as to be orthogonal to each other. In this way, a polarizing plate was produced.

[Comparative Example 1: Polarizing plate for comparison]
A polarizing plate was produced in the same manner as in Example 1 except that the cellulose acetate film produced in Production Example R1 was used.

[Examples 2 to 13: Polarizing plate of the present invention]
A polarizing plate was produced in the same manner as in Example 1 except that the cellulose acetate films produced in Production Examples 4 to 15 were used.

  Table 5 shows the results of evaluating the pencil hardness and the specular reflectance of the produced polarizing plate samples 1 to 13 and comparative example 1 polarizing plate sample.

Pencil Hardness Evaluation Based on the pencil hardness evaluation described in JIS K 5400, the side opposite to the optical compensation sheet surface of the polarizing plate, that is, the antireflection film surface was evaluated. After adjusting the polarizing plate for 2 hours at 25 ° C. and 60% RH, the highest pencil that evaluates to the following criteria with a load of 500 g using the test pencils H to B specified in JIS S 6006 and is OK. Hardness was used as an evaluation value. Higher hardness is preferred.
In evaluation of n = 5, there is no scratch to one scratch: OK
In the evaluation of n = 5, there are 3 or more scratches: NG
In addition, when the presence or absence of scratches was subtle and could not be clearly ranked, it was indicated by “˜” and indicated in that range. (Example: 3H-2H)

Specular reflectivity A spectrophotometer V-550 (manufactured by JASCO Corporation) is fitted with an adapter ARV-47, and in the wavelength range of 380 to 780 nm, the specular reflectivity at an output angle of 5 ° at an incident angle of 5 ° The average reflectance of 450 to 650 nm was calculated as the specular reflectance. A lower value is preferred.

[Example 14: Liquid crystal display device of the present invention]
A pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell are peeled off, and the polarizing plate prepared in Example 1 is used instead. Were attached to the observer side and the backlight side one by one through an adhesive so that the cellulose acetate film produced in Production Example 3 was on the liquid crystal cell side. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). The results are shown in Table 6.

[Example 15: Liquid crystal display device of the present invention]
A pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell are peeled off, and the polarizing plate prepared in Example 2 is used instead. Was attached to the observer side through an adhesive so that the cellulose acetate film produced in Production Example 4 was on the liquid crystal cell side. In addition, a commercially available polarizing plate (HLC2-5618HCS, manufactured by Sanritz Corporation) was attached to the backlight side. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). The results are shown in Table 6.

[Examples 16 to 26: Liquid crystal display device of the present invention]
A pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell were peeled off, and produced in Examples 3 to 13 instead. One polarizing plate was affixed to the observer side via an adhesive so that the cellulose acetate film produced in Production Examples 5 to 15 was on the liquid crystal cell side. Moreover, it stuck on the backlight side similarly. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). The results are shown in Table 6.

[Comparative Example 2: Liquid crystal display device for comparison]
A liquid crystal display device of Comparative Example 2 was produced in the same manner as Example 14 except that the polarizing plate of Comparative Example 1 was used instead of the polarizing plate of Example 1 used in Example 14.

[Comparative Example 3: Liquid crystal display device for comparison]
A liquid crystal display device of Comparative Example 3 was produced in the same manner as Example 15 except that the polarizing plate of Comparative Example 1 was used instead of the polarizing plate of Example 2 used in Example 15.

[Comparative Example 4: Liquid crystal display device for comparison]
About a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell, from a black display (L1) to a white display (L8) using a measuring machine (EZ-Contrast160D, manufactured by ELDIM). The viewing angle was measured in 8 stages. The results are shown in Table 6.

  From Table 6, it can be seen that the liquid crystal display devices of Examples 14 to 26 of the present invention have a wider viewing angle range than that of Comparative Example 4 without gradation inversion.

[Example 27: Liquid crystal display device of the present invention]
A pair of polarizing plates provided in a liquid crystal display device (6E-A3, manufactured by Sharp Corporation) using a TN type liquid crystal cell is peeled off, and a polarizing plate produced in Example 3 is produced in Production Example 5 instead. The obtained cellulose acetate film was attached to the viewer side and the backlight side one by one through an adhesive so that the cellulose acetate film was on the liquid crystal cell side. The transmission axis of the polarizing plate on the observer side and the transmission axis of the polarizing plate on the backlight side were arranged so as to be in the O mode. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). The results are shown in Table 7.

[Comparative Example 5: Liquid crystal display device for comparison]
About a liquid crystal display device (6E-A3, manufactured by Sharp Corporation) using a TN type liquid crystal cell, from a black display (L1) to a white display (L8) using a measuring device (EZ-Contrast 160D, manufactured by ELDIM) The viewing angle was measured in 8 stages. The results are shown in Table 7.

  In Example 27 of the present invention, the viewing angle range without gradation inversion is wide.

The following rubbing tests were carried out on the liquid crystal display device samples produced in Examples 14 to 27.
(Pencil hand rub strength)
A jig was prepared by joining a tube into which a pencil can be inserted into the lower side of the metal pan, and a pencil with a 3 cm long core was inserted into this tube. The tip of the lead was sharpened in a wedge shape at an angle of 60 °. The liquid crystal display device was placed horizontally so that the antireflection film faced upward, and the jig with a load of 0.5 kg was placed thereon, and the jig was rotated about 2 cm horizontally by hand. Change the pencil hardness moderately, change the rubbing location to 5 places, visually observe the antireflection film surface after rubbing, and determine the hardness of the pencil where only 2 or less scratches are recognized as the hardness of the sample. It was.
The results are shown in Table 8.

  From Table 8, it can be seen that the surfaces of the liquid crystal display devices of Examples 14 to 27 of the present invention have higher pencil hardness than Comparative Examples 2 to 5.

[Production Example 16: Cellulose acetate film with optical compensation function used in the present invention]
Using the finished dope prepared in Production Example 5, the following samples having different film thicknesses were produced by changing only the casting conditions (discharge amount of the finished dope).
Sample 16-1 film thickness 80 μm
Sample 16-2 film thickness 67 μm
Sample 16-3 film thickness 54 μm
Sample 16-4 film thickness 40 μm

[Examples 28 to 46: Polarizing plate of the present invention, Comparative examples 6 to 10: Comparative polarizing plate]
A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film. The cellulose acetate film samples 16-1 to 16-4 with an optical compensation function having different thicknesses produced in Production Example 16 were subjected to saponification treatment and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. . The antireflection film samples 101 to 109 and samples 201 to 204 that had been subjected to the saponification treatment were attached to opposite sides of the polarizing film with a polyvinyl alcohol adhesive. The transmission axis of the polarizing film and the slow axis of the cellulose acetate film with an optical compensation function prepared in Production Example 16 were arranged in parallel. The transmission axis of the polarizing film and the slow axis of the cellulose triacetate film of the antireflection film sample were arranged so as to be orthogonal to each other. In this way, a polarizing plate was produced.
The combinations of the polarizing plate sample and the antireflection film sample are as shown in Table 9 below. For comparison, a polarizing plate using a commercially available cellulose triacetate film (TD80UF manufactured by Fuji Photo Film Co., Ltd., film thickness 80 μm) was also added. Furthermore, the following 12 polarizing plates were produced.

[Comparative Example 11: Comparative polarizing plate]
Instead of the cellulose acetate film produced in Production Example 3 used for the polarizing plate produced in Example 1, a commercially available cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was subjected to saponification treatment, and a polyvinyl alcohol type A polarizing plate was prepared by pasting with an adhesive and pasting the antireflection film sample of Sample 103 on the surface opposite to the cellulose triacetate film surface in the same manner as in Example 1.

[Comparative Example 12: Comparative polarizing plate]
A conventional polarizing plate was prepared. That is, without applying an optical compensation sheet or an antireflection film on both sides of the polarizing film, a commercially available cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) is pasted with a polyvinyl alcohol adhesive. A polarizing plate was prepared.

The polarizing plates of Examples 28 to 46 and Comparative Examples 6 to 12 were evaluated as shown in the table below. Table 9 shows sample contents, evaluation contents, and results.

From Table 9, it is understood that the pencil hardness and the reflectance are more preferable when the polarizing plate of the present invention (the polarizing plate using the cellulose acetate film with an optical compensation function used in the present invention and the antireflection film used in the present invention) is used. .
For example, in comparison with Comparative Examples 6 to 9, Examples 30 to 33 are compared with Comparative Examples 7 to 10, and in Examples 42 to 45, the antireflection film used in the present invention is combined. Even if the film thickness of the acetate film changes, there is no difference in pencil hardness.
In addition, Examples 32 to 34 and Examples 42, 44, and 45 were preferable polarizing plates because the pencil hardness was not lowered even when the film thickness was relatively thin.

[Example 47: Polarizing plate of the present invention]
A sample 301 was prepared by applying the same coating as the sample 103 except that the coating solution for the antiglare hard coat layer of the antireflection film sample 103 was changed to C. Using this antireflection film sample and the cellulose acetate film sample with optical compensation function of Production Example 16-3, a polarizing plate was produced in the same manner as in Example 1.

[Example 48: Polarizing plate of the present invention]
A sample 302 was prepared by applying the same coating as the sample 103 except that the coating solution for the antiglare hard coat layer of the antireflection film sample 103 was changed to D. Using this antireflection film sample and the cellulose acetate film with an optical compensation function of Production Example 16-3, a polarizing plate was produced in the same manner as in Example 1.

Evaluation of transmission image clarity Using a Suga Test Instruments Co., Ltd. image clarity measuring device (ICM-2D type), the value of transmission image clarity was measured with an optical comb of 0.5 mm.
Table 10 shows the evaluation results of transmitted image clarity and pencil hardness.

From Table 10, it can be seen that the pencil hardness evaluation becomes harder when the transmitted image clarity is lowered.
The back sides of the samples of Examples 47 and 48 were painted black to evaluate antiglare properties. A sample was placed on a table and the ceiling fluorescent lamp was observed with a reflection image. In the sample of Example 47, the outline of the fluorescent lamp lamp was hardly understood. On the other hand, in the sample of Example 48, the outline of the fluorescent lamp lamp was slightly blurred, but both samples were within acceptable levels.

[Example 49: Liquid crystal display device of the present invention]
A pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell are peeled off, and a polarizing plate prepared in Example 3 is used instead. Was attached to the observer side through an adhesive so that the cellulose acetate film produced in Production Example 5 was on the liquid crystal cell side. In addition, a commercially available polarizing plate (HLC2-5618HCS, manufactured by Sanritz Corporation) was attached to the backlight side. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). As a result, the viewing angle in the direction of the transmission axis and the direction of 45 ° from the transmission axis (the range where the contrast ratio is 10 or more and there is no black-side gradation inversion) is preferably 80 ° or more. At the same time, the background was very little reflected on the screen, and the display quality was excellent.

[Example 50: Liquid crystal display device of the present invention]
A pair of polarizing plates and a pair of optical compensation sheets provided in a liquid crystal display device (VL-1530S, manufactured by Fujitsu Limited) using a vertical alignment type liquid crystal cell are peeled off, and the polarizing plate prepared in Example 45 is used instead. Were attached to the observer side and the backlight side one by one through an adhesive so that the produced cellulose acetate film was on the liquid crystal cell side. The crossed Nicols were arranged so that the transmission axis of the polarizing plate on the viewer side was in the vertical direction and the transmission axis of the polarizing plate on the backlight side was in the horizontal direction. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). As a result, the viewing angle in the direction of the transmission axis and the direction of 45 ° from the transmission axis (the range where the contrast ratio is 10 or more and there is no black-side gradation inversion) is preferably 80 ° or more. At the same time, the background was very little reflected on the screen, and the display quality was excellent.

Example 51 Liquid Crystal Display Device of the Present Invention
A pair of polarizing plates provided in a liquid crystal display device (6E-A3, manufactured by Sharp Corporation) using a TN type liquid crystal cell was peeled off, and instead the polarizing plate produced in Example 45 was replaced with Production Example 16-3. The cellulose acetate film with an optical compensation function produced in step 1 was attached to the viewer side and the backlight side one by one through an adhesive so that the film was on the liquid crystal cell side. The transmission axis of the polarizing plate on the observer side and the transmission axis of the polarizing plate on the backlight side were arranged so as to be in the O mode. About the produced liquid crystal display device, the viewing angle was measured in eight steps from black display (L1) to white display (L8) using the measuring machine (EZ-Contrast160D, ELDIM company make). As a result, the viewing angle (range with a contrast ratio of 10 or more and no black-side gradation inversion) was 18 ° upward, 24 ° downward, and 77 ° laterally. At the same time, the background was very little reflected on the screen, and the display quality was excellent.

  The pencil hand rub strength test was carried out on the liquid crystal display device samples prepared in Examples 49-51. As a result, Examples 49 to 51 all had a pencil hardness of 2H. As a result, it can be seen from the comparison with the pencil hand rub strengths of Comparative Examples 2 to 5 that the liquid crystal display devices of Examples 49 to 51 have a high pencil hardness.

FIG. 1 is a schematic cross-sectional view showing the layer structure of an antireflection film used in the present invention. FIG. 2 is a schematic cross-sectional view showing the layer structure of the antireflection film used in the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antireflection film 2 Transparent support 3 Hard coat layer 4 Anti-glare hard coat layer 5 Low refractive index layer (outermost layer)
6 Matting agent particles 7 Middle refractive index layer 8 High refractive index layer

Claims (9)

A polarizing plate in which at least one functional film is disposed on both sides of the polarizing film,
At least one of the functional films on one side is composed of only one cellulose acylate film, and the cellulose acylate film is an aromatic having at least two aromatic rings with respect to 100 parts by mass of the cellulose acylate. 0.01 to 20 parts by mass of the compound, the Re retardation value defined by the following formula (I) is 20 to 70 nm, and the Rth retardation value defined by the following formula (II) is 70 to 400 nm. ,
At least one of the functional films on the other side is at least one of an antiglare hard coat layer, a hard coat layer having no antiglare property, a medium refractive index layer, or a high refractive index layer on a transparent support. A polarizing plate comprising an antireflection film having a layer and a low refractive index layer.
(I) Re = (nx−ny) × d
(II) Rth = {(nx + ny) / 2−nz} × d
Where nx is the refractive index in the slow axis direction in the film plane; ny is the refractive index in the fast axis direction in the film plane; nz is the refractive index in the thickness direction of the film; and d Is the thickness of the film. ] A polarizing plate in which at least one functional film is disposed on both sides of the polarizing film,
At least one of the functional films on one side is composed of only one cellulose acylate film, and the cellulose acylate film is an aromatic having at least two aromatic rings with respect to 100 parts by mass of the cellulose acylate. 0.01 to 20 parts by mass of the compound, the Re retardation value defined by the following formula (I) is 20 to 70 nm, and the Rth retardation value defined by the following formula (II) is 70 to 400 nm. ,
At least one of the functional films on the other side is made of an antireflection film having at least one of an antiglare hard coat layer or a high refractive index layer and a low refractive index layer on a transparent support. A polarizing plate characterized by.
(I) Re = (nx−ny) × d
(II) Rth = {(nx + ny) / 2−nz} × d
Where nx is the refractive index in the slow axis direction in the film plane; ny is the refractive index in the fast axis direction in the film plane; nz is the refractive index in the thickness direction of the film; and d Is the thickness of the film. ]   The polarizing plate according to claim 1 or 2, wherein the cellulose acylate film has a thickness of 40 µm or more and 70 µm or less.   The polarizing plate according to claim 1, wherein the aromatic compound is a rod-shaped compound having a linear molecular structure. An organosilane represented by the following general formula (1) is used in the composition for forming at least one of a hard coat layer having no antiglare property, an antiglare hard coat layer and a low refractive index layer of the antireflection film. The polarizing plate according to claim 1, comprising a compound, and / or a hydrolyzate thereof, and / or a partial condensate thereof.
Formula ^{(1): (R 10)} m -Si (X) 4-m
[In the general formula (1), R ¹⁰ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. X represents a hydroxyl group, an alkoxy group, a halogen atom, or an R ² COO group, R ² represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and m represents an integer of 1 to 3. ]   The low refractive index layer of the antireflective film contains at least one silica fine particle, at least one of the silica fine particles is a hollow silica fine particle, and the refractive index of the fine particle is 1.17 to 1.40. It exists, The polarizing plate in any one of Claims 1-5 characterized by the above-mentioned.   The anti-glare hard coat layer of the antireflection film contains matting agent particles and a binder, and a difference in refractive index between the matting agent particles and the binder is 0.03 or more and 0.2 or less. The polarizing plate in any one of Claims 1-6.   A liquid crystal display device, wherein the polarizing plate according to claim 1 is used on an outermost surface of the liquid crystal display device.   9. The liquid crystal display device according to claim 8, wherein the liquid crystal cell of the liquid crystal display device is a VA mode or TN mode liquid crystal cell.

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