JP2005037739A - Antireflection film, polarizing plate and image display apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive multilayer antireflection film having high antireflection performance, excellent physical strength and excellent productivity, or a multilayer antireflection film having high antireflection performance and physical strength and excellent weather resistance, to provide a polarizing plate subjected to an antireflection process by a proper means, and to provide an image display apparatus. <P>SOLUTION: The multilayer antireflection film having at least two refractive index layers including a high refractive index layer and a low refractive index layer successively deposited on a transparent substrate is characterized in that the surface of the high refractive index layer has 0.001 to 0.03 μm arithmetic average roughness (Ra), 0.001 to 0.06 μm ten-point average roughness (Rz) and ≤0.09 μm maximum height (Ry) based on JISB0601-1994. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an antireflection film, and forms an optical multilayer film that imparts optical selective permeability or absorbency to a transparent substrate such as glass or plastic (hereinafter also referred to as a transparent support). The present invention relates to a high-refractive-index layer that can be used, a multilayer laminated antireflection film including the layer (hereinafter also referred to as a multilayer antireflection film), and an image display device using the same.

  Conventionally, an antireflection layer used for an antireflection film (hereinafter also referred to as an antireflection film) is formed by sequentially laminating a middle refractive index layer, a high refractive index layer, and a low refractive index layer. A multilayer film in which metal oxide films having different rates are stacked is used. As a transparent thin film of metal oxide, a method of forming a thin film by a chemical vapor deposition (CVD) method, a physical vapor deposition (PVD) method, or the like has been proposed.

However, these metal oxide transparent thin film forming methods by vapor deposition have low productivity and are not suitable for mass production, and methods of forming by high productivity coating have been proposed.
When the antireflection film is prepared by coating, the refractive index of each layer to be laminated is adjusted by appropriately selecting the binder resin of the matrix forming the layer and the refractive index of the particles dispersed in the matrix and the content in the layer. Has been done.

  As a coating-type high refractive index layer, for example, ultrafine particles of inorganic oxide having a refractive index of 1.9 or more are used in a binder considering the hardness, adhesion, toughness of the high refractive index layer, and dispersibility of the high refractive index ultrafine particles. Various cured thin films have been proposed. In particular, a technique for improving the strength as a cured film by uniformly dispersing inorganic particles to be used together in ultrafine particles and firmly bonding the fine particles (Patent Document 1), and unevenness of the film caused by the particles dispersed in the binder It has been proposed to reduce the failure of optical foreign matters as an optical film by defining the size (Patent Document 2). The antireflective film has a low refractive index layer composed of a metal compound containing layer such as silicon dioxide and magnesium fluoride or a fluorine containing compound containing layer having a high fluorine atom content on the high refractive index layer. A cured film is provided. The metal compound-containing layer, that is, the inorganic compound-containing layer, or the fluorine-containing compound-containing layer having a high fluorine atom content, used as the lower refractive index layer, has a low cohesive force, and both have adhesion to the lower cured film. Is lacking. As an improvement method, it has been proposed to provide an anchoring effect by providing an uneven shape with a centerline surface roughness (Ra) having a specific size on the surface of the high refractive index layer (Patent Document 3).

JP-A-11-153703 JP 2001-74936 A Japanese Patent Laid-Open No. 2002-311204

On the other hand, with the recent increase in the size of image display devices or the development of mobile devices, there are increasing demands for the clarity of display images and the durability as a protective film (such as scratch resistance and weather resistance).
However, in order to make a high refractive index layer as a multilayer laminated antireflection film, the use ratio of the inorganic particles such as titanium-based high refractive index fine particles that determine optical characteristics in the layer must be increased. However, it is difficult for conventional antireflection films to maintain sufficient strength (hardness, scratch resistance, physical strength such as adhesion, weather resistance). Since these optical multilayer films are used as the outermost layer of the article, the performance as a protective film having further durability is desired.
Accordingly, an object of the present invention is to provide a multilayer antireflection film having high antireflection performance, excellent physical strength, inexpensive, and excellent in productivity.
Another object of the present invention is to provide a multilayer antireflection film having high antireflection performance and physical strength and excellent weather resistance.
Still another object of the present invention is to provide a polarizing plate and an image display device excellent in antireflection performance.

The above-mentioned problems of the present invention are achieved by the following.
(1) In a multilayer antireflection film having at least two refractive index layers of a high refractive index layer and a low refractive index layer in this order on a transparent support, JIS B0601-1994 is formed on the surface of the high refractive index layer. The arithmetic average roughness (Ra) of the surface irregularities based on the above is 0.001 to 0.03 μm, the ten-point average roughness (Rz) is in the range of 0.001 to 0.06 μm, and the maximum height (Ry ) Is formed in a concavo-convex shape of 0.09 μm or less.
(2) Ratio of arithmetic average roughness (Ra) and ten-point average roughness (Rz) of the surface irregularities (Ra / Rz is 0.1 or more and surface irregularities of the film based on JISB0601-1994) The antireflection film as described in (1) above, wherein the average distance (Sm) is 1 μm or less.
(3) The high refractive index layer is composed of a cured film having a refractive index of 1.55 to 2.5, and the antireflection film has an abrasion amount of 50 mg or less in a Taber abrasion test based on JISK-6902. The antireflection film according to (1) or (2) above.

(4) The high refractive index layer contains inorganic fine particles mainly composed of titanium dioxide containing at least one metal atom selected from cobalt, aluminum, and zirconium, and the layer has a refractive index of 1.55 to 2. The antireflection film according to any one of (1) to (3) above, which is a cured film of .50.
(5) The antireflection film as described in any one of (1) to (4) above, wherein the metal atom contained in the inorganic fine particles mainly composed of titanium dioxide is cobalt.
(6) Both the haze after 150 hours treatment based on accelerated weather resistance JISK5600-7-7: 1999 and the wear amount in the Taber abrasion test based on JISK-6902 are the layers before the weather resistance test. The antireflection film as described in any one of (4) and (5) above, wherein the rate of change is 10% or less.

(7) The number of luminance defects having a diameter of 50 μm or more, which is an optical foreign matter generated after 150 hours of treatment according to the accelerated weather resistance JISK5600-7-7: 1999, is 20 or less per square meter. The antireflection film as described in any one of (4) to (6) above,
(8) The above (1) to (7), wherein the high refractive index layer is formed of at least one matrix selected from an organic binder, an organometallic compound, and a partial hydrolyzate of an organometallic compound. The antireflection layer according to any one of the above.
(9) On the transparent support, the cured film according to any one of (1) to (8) is laminated in two layers having different refractive indexes, and a low refractive index layer having a refractive index of less than 1.55 is further laminated. An antireflection film characterized in that a three-layer structure is formed.

(10) The antireflection film as described in any one of (1) to (9) above, wherein a hard coat layer is provided between the transparent support and the high refractive index layer.
(11) A polarizing plate, wherein the antireflection film according to any one of (1) to (10) is used for at least one of the protective films of the polarizing film.
(12) The antireflection film according to any one of (1) to (10) is used for one of the protective films for the polarizing film, and the optical compensation film having optical anisotropy is used for the other protective film for the polarizing film. A polarizing plate characterized by
(13) The antireflection film according to any one of (1) to (10) above or the polarizing plate according to any one of (11) or (12) above is disposed on an image display surface. An image display device.

The present invention is characterized in that a high refractive index layer having a higher refractive index than that of the transparent support is formed on the transparent support, and the surface form of the high refractive index layer is finely controlled. That is,
(A) The arithmetic average roughness (Ra) of the surface irregularities based on JISB0601-1994 is 0.001 to 0.03 μm, the ten-point average roughness (Rz) is 0.001 to 0.06 μm, and The maximum height (Ry) is 0.09 μm or less.
By making the surface of the high refractive index layer in this way, the adhesion with the low refractive index layer further coated on this layer becomes extremely good, and the film strength of the high refractive index layer itself is sufficient. It was found to be something. This is because the present invention is applied to a cured film composed of a metal compound-containing layer coated on a high-refractive index layer or a low-refractive index layer mainly composed of a fluorine-containing low-refractive index resin having a low cohesive force. It is presumed that anchoring with the surface of the high refractive index layer was uniformly expressed. In addition, it is preferable to make the surface irregularities of the high refractive index layer as described above in that the optical performance is not substantially affected as compared with the case where the irregularities are not formed.

In order to make the range in the above (A), the inorganic fine particles contained in the high refractive index layer have an ultra fine particle size and the particle size is uniform, and the inorganic fine particles are uniformly dispersed in the high refractive index layer. It has been found that this can be achieved.
The inorganic fine particles are described in detail in [High Refractive Index Particles] in the following <High Refractive Index Composition>, the ultrafine particles are described in detail in [Infrared Fine Particles] and the dispersion is described in the following [ [Dispersant] and [Dispersion medium].

Furthermore, (B) the ratio of the arithmetic average roughness (Ra) to the ten-point average roughness (Rz) (Ra / Rz is 0.1 or more, and the surface unevenness of the film based on JIS B0601-1994 It was found that when the average distance (Sm) is 1 μm or less, a remarkably strong antireflection film free from foreign matter that causes optical defects can be obtained, where Ra / Rz is 0. When the ratio is 1 or more, the unevenness of the surface irregularities becomes small.
The range in the above (B) is achieved by forming so as not to have coarse particles or aggregates. Specifically, 1) filter filtration and 2) dust removal are effective.
Filter filtration will be described in detail later in [Formation of high refractive index layer], and dust removal will be described in detail later in [Formation of antireflection film].

Furthermore, the weather resistance was remarkably improved by using specific titanium oxide fine particles as the high refractive index particles.
The inorganic fine particles mainly composed of titanium oxide, particularly titanium dioxide, will be described in detail in [High Refractive Index Particles] in <High Refractive Index Composition> below.

By producing a high refractive index layer containing complex oxide fine particles composed of atoms selected from specific elements, detailed in this specification, an antireflection film excellent in weather resistance (particularly light resistance) can be produced at low cost. Can be provided in large quantities.
Furthermore, the polarizing plate and image display apparatus which hold | maintained the said characteristic by these can be provided.

Hereinafter, the antireflection film of the present invention will be described in detail.
<Layer structure of antireflection film>
The high refractive index layer (hereinafter also referred to as a high refractive index film) according to the present invention is a multilayer antireflection film in which two or more layers (light transmissive layers) having light transmittance and different refractive indexes are laminated. Formed as a single layer.
The antireflection film composed of two layers has a layer structure in the order of a transparent support, a high refractive index layer, and a low refractive index layer (outermost layer). The transparent support, the high refractive index layer, and the low refractive index layer have a refractive index that satisfies the following relationship.
Refractive index of high refractive index layer> Refractive index of transparent support> Refractive index of low refractive index layer Also, a hard coat layer is provided between the transparent support and the high refractive index layer, and a low refractive index layer is further laminated. Also good. Or it may consist of an anti-glare high refractive index layer and a low refractive index layer.

The antireflection film composed of three layers has a layer structure in the order of a transparent support, a middle refractive index layer, a high refractive index layer, and a low refractive index layer (outermost layer). The transparent support, the middle refractive index layer, the high refractive index layer, and the low refractive index layer have a refractive index that satisfies the following relationship.
The refractive index of the high refractive index layer> The refractive index of the medium refractive index layer> The refractive index of the transparent support> The refractive index of the low refractive index layer. Also, a hard coat layer is provided between the transparent support and the medium refractive index layer. A high refractive index layer and a low refractive index layer may be laminated.
Each layer in such a multi-layer structure has an antireflection film having better antireflection performance that satisfies the relationship between the film thickness of each layer and the visible light wavelength, as described in JP-A-2001-188104. Is preferable in that it can be manufactured.
The high refractive index, medium refractive index, and low refractive index described here refer to the relative refractive index between layers.
In the antireflection film of the present invention having the above layer structure, it is preferable to use at least a high refractive index layer improved according to the present invention.

<High refractive index layer>
The high refractive index layer of the present invention comprises a cured film having a refractive index of 1.55 to 2.50 obtained by coating a curable composition containing at least inorganic fine particles having a high refractive index and a matrix binder. The refractive index is preferably 1.65 to 2.40, more preferably 1.70 to 2.20.

  The surface of the high refractive index layer forms a fine surface irregularity having a size that does not optically affect, and the arithmetic average roughness (Ra) of the surface irregularity of the film based on JIS B0601-1994 is 0.001. It is characterized by having a ten-point average roughness (Rz) in the range of 0.001 to 0.06 μm and a maximum height (Ry) of 0.09 μm or less. Further, the arithmetic average roughness (Ra) is 0.001 to 0.015 μm, the ten-point average roughness (Rz) is in the range of 0.002 to 0.05 μm, and the maximum height (Ry) is 0.00. 05 μm or less is preferable. In particular, the arithmetic average roughness (Ra) is 0.001 to 0.010 μm, the ten-point average roughness (Rz) is 0.002 to 0.025 μm, and the maximum height (Ry) is 0.00. 04 μm or less is preferable.

Furthermore, in the above-described fine surface irregularity of a size that does not affect optically, the ratio (Ra / Rz) to the ten-point average roughness (Rz) is 0.1 or more, and based on JISB0601-1994. The average interval (Sm) of the surface irregularities of the film is preferably 1 μm or less. Here, the relationship between Ra and Rz indicates the uniformity of surface irregularities. Preferably, the (Ra / Rz) ratio is 0.15 or more, and the average interval (Sm) is 0.01 to 0.8 μm.
The concave and convex shapes on the film surface can be evaluated by an atomic force microscope (AFM).

  Usually, the refractive index of the matrix binder is 1.4 to 1.5, and the use ratio of the inorganic fine particles is determined by the refractive index of the inorganic particles used. In order to obtain a high refractive index cured film having a refractive index of 1.55 to 2.50 formed by dispersing high refractive index inorganic fine particles in a matrix binder, the amount of inorganic fine particles is not related to the refractive index, but the total mass of the cured film. The content is preferably 40 to 80% by mass, more preferably 45 to 75% by mass. In order to increase the film strength of the high refractive index layer itself and to strengthen the adhesion with the upper layer when the upper layer is laminated in the high refractive index layer designed by increasing the inorganic particle ratio as described below, As described above, the inorganic fine particles have an ultrafine particle size and the particle size is uniform, the inorganic fine particles are uniformly dispersed in the high refractive index layer, and the surface of the high refractive index layer exhibits the above-described uneven state. It has been found that it can be achieved by forming.

By setting the shape and distribution of surface irregularities on the entire surface of the layer to a specific range, even when an upper layer is continuously formed on a long film, the entire surface of the film is evenly and uniformly anchored with sufficient anchoring effect. Is preserved. Further, the adhesiveness is maintained without change even after storage for a long time.
The adhesion in the present invention is the adhesion between a cured film having a high refractive index and an upper layer (low refractive index layer) coated on the hard film. The more the surface unevenness is maintained, the stronger the adhesion is. Therefore, the smaller the amount of wear in the Taber abrasion test based on JISK-6902, the greater the adhesion, and the amount of abrasion in the Taber abrasion test is preferably 50 mg or less. Specifically, this is the amount of wear after 500 revolutions at a load of 1 kg, and the amount of wear is more preferably 40 mg or less. Within this range, the scratch resistance as the antireflection film is sufficiently maintained, which is preferable.
Further, the antireflection film including the high refractive index layer that forms the surface shape described above is preferable because the number of luminance defects having a diameter of 50 μm or more that is visually noticeable as a foreign substance is 20 or less per square meter.

Below, the high refractive index layer which forms the specific surface state of this invention is further demonstrated.
<Composition for high refractive index layer>
[High refractive index particles]
The high refractive index inorganic fine particles contained in the high refractive index layer of the present invention have a refractive index of 1.80 to 2.80 and an average primary particle size of 3 to 150 nm. Particles having a refractive index of less than 1.80 are not preferred because the effect of increasing the refractive index of the film is small, and particles having a refractive index of more than 2.80 are colored. In addition, particles having an average primary particle diameter exceeding 150 nm are not preferable because the haze value when a film is formed is high, and the transparency of the film is impaired, and if it is less than 3 nm, it is difficult to maintain a high refractive index. In the present invention, the inorganic fine particles are more preferably particles having a refractive index of 1.90 to 2.80 and an average primary particle size of 3 to 100 nm, and further a refractive index of 1.90 to 2.80 and a primary particle. Particles having an average particle size of 5 to 80 nm are preferred.

  Specific examples of preferable high refractive index inorganic fine particles include metal atoms such as Ti, Zr, Ta, In, Nd, Sn, Sb, Zn, La, W, Ce, Nb, V, Sm, and Y. Or the particle | grains which have complex oxide and a sulfide as a main component are mentioned. Here, the main component refers to a component having the largest content (mass%) among the components constituting the particles. In the present invention, particles having an oxide or composite oxide containing at least one metal atom selected from the metal elements Ti, Zr, Ta, In and Sn as a main component are preferable. The inorganic fine particles used in the present invention may contain various metal atoms in the particles. Examples thereof include Li, Si, Al, B, Ba, Co, Fe, Hg, Ag, Pt, Au, Cr, Bi, P, and S. In the case of tin oxide and indium oxide, it is preferable to contain metal atoms such as Sb, Nb, P, B, In, V, and halogen in order to increase the conductivity of the particles, and in particular, about 5 to 20 mass of antimony oxide. % Is most preferable.

Particularly preferred are inorganic fine particles (hereinafter sometimes referred to as “specific oxides”) mainly composed of titanium dioxide containing at least one metal atom selected from Co, Al, and Zr. A particularly preferred metal atom is Co. The total content of Co, Al, and Zr with respect to Ti is preferably 0.05 to 30% by mass, more preferably 0.1 to 10% by mass, still more preferably 0.2 to 7% by mass, and particularly preferably. Is 0.3-5 mass%, and 0.5-3 mass% is the most preferable.
Co, Al, and Zr are present inside or on the surface of inorganic fine particles mainly composed of titanium dioxide, more preferably present inside inorganic fine particles mainly composed of titanium dioxide, and are present both on the inside and on the surface. Most preferably. These specific metal atoms may exist as oxides.

  As another preferable inorganic fine particle, a composite oxide of titanium atom and at least one selected from metal atoms whose oxide has a refractive index of 1.90 or more (hereinafter, this metal atom is also abbreviated as “Met”). And the composite oxide is an inorganic fine particle doped with at least one metal ion selected from Co ions, Al ions and / or Zr ions (sometimes referred to as “specific composite oxide”). Is mentioned. Here, the elements Ta, Zr, In, Nd, Sb, Sn, and Bi are preferable as the metal atom of the metal oxide having a refractive index of 1.95 or more. In particular, Ta, Zr, Sn, and Bi are preferable. The content of the metal ions doped in the composite oxide is preferably within a range not exceeding 25 mass% with respect to the total amount of metal [Ti + Met] constituting the composite oxide from the viewpoint of maintaining the refractive index. More preferably, it is 0.05-10 mass%, More preferably, it is 0.1-5 mass%, and 0.3-3 mass% is the most preferable.

The doped metal ion may be present as either a metal ion or a metal atom, is appropriately present from the surface to the inside of the complex oxide, and is preferably present both on the surface and inside.
The inorganic fine particles of the present invention preferably have a crystal structure. The crystal structure is preferably composed mainly of a rutile, rutile / anatase mixed crystal, anatase, or amorphous structure, and particularly preferably a rutile structure.
Thus, the inorganic fine particles of the specific oxide or specific double oxide of the present invention have a refractive index of 1.90 to 2.80, preferably 2.10 to 2.80, and 2.20. More preferably, -2.80. Further, by using a specific oxide or a specific double oxide, the photocatalytic activity of titanium dioxide can be suppressed, and the weather resistance of the high refractive index layer of the present invention can be remarkably improved, which is preferable.

  A conventionally known method can be used as a method for doping the specific metal atom or metal ion. For example, methods described in JP-A-5-330825, 11-263620, JP-A-11-512336, European Patent Application No. 0335773, etc., ion implantation methods (for example, Shunichi Gonda, Junzo Ishikawa, Eiji Kamijo, “Ion Beam Applied Technology” CMC Co., Ltd., 1989, Yasushi Aoki, “Surface Science”, 1998, Vol. 18, No. 5, p. 262, Shoichi Anbo, etc. , “Surface Science”, 1999, Vol. 20, No. 2, p. 60, etc.).

The inorganic fine particles of the present invention may be surface treated. In the surface treatment, the surface of the particles is modified using an inorganic compound and / or an organic compound, the wettability of the surface of the inorganic particles is adjusted, and the particles are finely divided in an organic solvent. Improve dispersibility and dispersion stability. Examples of inorganic compounds that cause physicochemical adsorption on the particle surface include silicon-containing inorganic compounds (such as SiO ₂ ), aluminum-containing inorganic compounds (such as Al ₂ O ₃ and Al (OH) ₃ ), and cobalt. Inorganic compounds (CoO ₂ , Co ₂ O ₃ , Co ₃ O ₄ etc.), inorganic compounds containing zirconium (ZrO ₂ , Zr (OH) ₄ etc.), inorganic compounds containing iron (Fe ₂ O ₃ etc.) And so on.

As examples of organic compounds used for the surface treatment, conventionally known surface modifiers of inorganic fillers such as metal oxides and inorganic pigments can be used. For example, it is described in “Pigment Dispersion Stabilization and Surface Treatment Technology / Evaluation”, Chapter 1 (Technical Information Association, 2001).
Specifically, an organic compound having a polar group having an affinity for the surface of the inorganic particles and a coupling compound are exemplified. Examples of the polar group having affinity with the surface of the inorganic particles include a carboxy group, a phosphono group, a hydroxy group, a mercapto group, a cyclic acid anhydride group, an amino group, and the like, and a compound containing at least one kind in the molecule is preferable. . For example, long chain aliphatic carboxylic acids (eg stearic acid, lauric acid, oleic acid, linoleic acid, linolenic acid etc.), polyol compounds (eg pentaerythritol triacrylate, dipentaerythritol pentaacrylate, ECH modified glycerol triacrylate etc.), Examples thereof include phosphono group-containing compounds (for example, EO (ethylene oxide) -modified phosphoric acid triacrylate) and alkanolamines (ethylenediamine EO adduct (5 mol), etc.).

As a coupling compound, a conventionally well-known organometallic compound is mentioned, A silane coupling agent, a titanate coupling agent, an aluminate coupling agent etc. are mentioned as a typical thing. Of these, silane coupling agents are most preferred. Specific examples include compounds described in paragraphs [0011] to [0015] in JP-A Nos. 2000-9908 and 2001-310423.
Two or more kinds of these surface treatments can be used in combination.

The fine particles comprising the oxide of the present invention (hereinafter also referred to as oxide fine particles) are also preferably fine particles having a core / shell structure that forms a shell made of an inorganic compound using the fine particles as a core. The shell is preferably an oxide composed of at least one element selected from Al, Si, and Zr. Specifically, for example, the contents described in JP-A-2001-166104 can be mentioned.
The shape of the inorganic fine particles used in the present invention is not particularly limited, but is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape, or an indefinite shape. The inorganic fine particles of the present invention may be used alone, but it is also preferable to use two or more kinds in combination.

[Dispersant]
In order to use the ultrafine particles in which the inorganic particles of the present invention are stably dispersed, it is preferable to use a dispersant in combination. The dispersant is preferably a low molecular compound or a high molecular compound having a polar group having an affinity for the surface of the inorganic fine particles.
Examples of the polar group include a hydroxy group, a mercapto group, a carboxyl group, a sulfo group, a phosphono group, an oxyphosphono group, a —P (═O) (R ₁ ) (OH) group, and —O—P (═O) (R ₁ ) (OH) group, amide group (—CONHR ₂ , —SO ₂ NHR ₂ ), cyclic acid anhydride-containing group, amino group, quaternary ammonium group and the like.

Here, R ₁ represents a hydrocarbon group having 1 to 18 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group, dodecyl group, octadecyl group, chloroethyl group, methoxy group) Ethyl group, cyanoethyl group, benzyl group, methylbenzyl group, phenethyl group, cyclohexyl group, etc.). R ₂ represents a hydrogen atom or the same content as R ₁ .

In the polar group, the group having a dissociable proton may be a salt thereof.
The amino group and quaternary ammonium group may be any of primary amino group, secondary amino group or tertiary amino group, and more preferably tertiary amino group or quaternary ammonium group. The group bonded to the nitrogen atom of the secondary amino group, tertiary amino group or quaternary ammonium group is a hydrocarbon group having 1 to 12 carbon atoms (such as those having the same contents as the above R ₁ group). It is preferable. The tertiary amino group may be a ring-forming amino group containing a nitrogen atom (for example, a piperidine ring, a morpholine ring, a piperazine ring, a pyridine ring, etc.), and the quaternary ammonium group is a cyclic amino group. Or a quaternary ammonium group. In particular, an alkyl group having 1 to 6 carbon atoms is more preferable.

The counter ions of the quaternary ammonium group are halide ions, PF ₆ ions, SbF ₆ ions, BF ₄ ions, B (R ₃ ) 4 ions (R ₃ represents a hydrocarbon group, for example, butyl group, phenyl group, tolyl Group, naphthyl group, butylphenyl group, etc.), sulfonate ions and the like are preferable.

  The polar group of the dispersant according to the present invention is preferably an anionic group having a pKa of 7 or less or a salt of these dissociating groups. In particular, a carboxyl group, a sulfo group, a phosphono group, an oxyphosphono group, or a salt of these dissociating groups is preferable.

The dispersant preferably further contains a crosslinkable or polymerizable functional group. As the crosslinkable or polymerizable functional group, an ethylenically unsaturated group (for example, (meth) acryloyl group, allyl group, styryl group, vinyloxy group carbonyl group, vinyloxy group, etc.) capable of addition reaction / polymerization reaction by radical species, And cationically polymerizable groups (epoxy groups, thioepoxy groups, oxetanyl groups, vinyloxy groups, spiroorthoester groups, etc.), polycondensation reactive groups (hydrolyzable silyl groups, etc., N-methylol groups) and the like, preferably ethylene. An unsaturated group, an epoxy group, or a hydrolyzable silyl group.
Specific examples include compounds described in paragraph numbers [0013] to [0015] in JP-A No. 2001-310423.

The dispersant used in the present invention is also preferably a polymer dispersant. In particular, a polymer dispersant containing an anionic group and a crosslinkable or polymerizable functional group is preferable.
The mass average molecular weight (Mw) of the polymer dispersant is not particularly limited, and is preferably 1 × 10 ³ or more as a polystyrene conversion value measured by the GPC method. More preferable Mw is 2 × 10 ³ to 1 × 10 ⁶ , further preferably 5 × 10 ³ to 1 × 10 ⁵ , and particularly preferably 8 × 10 ³ to 8 × 10 ⁴ .
Within the above range, inorganic fine particles are easily dispersed, and a stable dispersion free from aggregates and precipitates can be obtained, which is preferable.

  The polar group, the crosslinkable or polymerizable functional group in the polymer dispersant is a terminal of the main chain of the polymer of the polymer chain or a side chain substituent of the polymer forming unit (hereinafter also referred to as a side chain in some cases). The polar group is preferably bonded to the end of the main chain and / or the side chain of the polymer, and the crosslinkable or polymerizable functional group is preferably bonded to the side chain.

As a method for introducing a polar group into the side chain, for example, a polar group-containing monomer (for example, (meth) acrylic acid, maleic acid, partially esterified maleic acid, itaconic acid, crotonic acid, 2-carboxyethyl (meth) acrylate, 2 -Sulfoethyl (meth) acrylate, 2-phosphonooxyethyl (meth) acrylate, 2,3 dihydroxypropyl (meth) acrylate, 2-N, N dimethylaminoethyl (meth) acrylate, (meth) acryloyloxyethyl trimer ammonium・ Methods of polymerizing PF ₆ ion salts, hydroxyl group-containing unsaturated compounds and cyclic acid anhydrides (maleic acid anhydride, glutaric acid anhydride, phthalic acid anhydride, etc.)), use of polymer reactions Methods used (for example, hydroxyl groups, amino groups, epoxy groups and acid anhydrides, halogen-substituted acids Reaction with compounds, can be synthesized by reaction, etc.) and the like of isocyanate groups, carboxyl group and a hydroxyl group, an acid compound containing an amino group.

Specific examples of the polymerization component of the polar group-containing polymer include, for example, the contents described in paragraphs [0024] to [0041] of JP-A No. 11-153703.
Further, in the polymer dispersant having a polar group in the side chain, the composition of the polar group-containing polymer is in the range of 0.5 to 50% by mass of the total polymer forming units, preferably Is 1 to 40% by mass, particularly preferably 5 to 30% by mass.

  On the other hand, as a method of introducing a polar group at the terminal, a method of performing a polymerization reaction in the presence of a polar group-containing chain transfer agent (for example, thioglycolic acid), a polar group-containing polymerization initiator (for example, Wako Pure Chemical Industries, Ltd.) V-501) or a polymerization reaction using a chain transfer agent or a polymerization initiator containing a reactive group such as a halogen atom, a hydroxyl group, or an amino group, followed by a polymer reaction or the like. Can be synthesized.

  When the crosslinkable or polymerizable functional group is contained in the side chain of the main chain of the polymer, the crosslinkable or polymerizable functional group has the number of atoms connecting from the polymer main chain to the crosslinkable or polymerizable functional group ( The total number of carbon atoms, excluding hydrogen atoms substituted with nitrogen atoms, silicon atoms, and the like is preferably 6 or more, more preferably 8 to 22. Thereby, a crosslinking reaction or a polymerization reaction is more likely to proceed.

  Moreover, it is preferable that the dispersing agent which concerns on this invention has a polymer formation unit which has an ethylenically unsaturated group as a crosslinkable or polymerizable functional group as mentioned above in a side chain. Examples of the polymer forming unit having an ethylenically unsaturated group in the corresponding side chain include poly-1,2-butadiene and poly-1,2-isoprene structures, or esters or amides of (meth) acrylic acid. And those having a specific residue (the R group of —COOR or —CONHR) bound thereto are preferred.

Examples of the specific residue (R group) include — (CH ₂ ) _n —CR ₁₁ ═CR ₁₂ R ₁₃ , — (CH ₂ O) _n —CH ₂ CR ₁₁ ═CR ₁₂ R ₁₃ , — (CH ₂ CH ₂ O) _n -CH ₂ CR ₁₁ = CR ₁₂ R ₁₃ ,-(CH ₂ ) _n -NH-CO-O-CH ₂ CR ₁₁ = CR ₁₂ R ₁₃ ,-(CH ₂ ) _n -O-CO -CR ₁₁ = CR ₁₂ R ₁₃ and-(CH ₂ CH ₂ O) ₂ -W can be mentioned. (Wherein R _{11 to} R ₁₃ represent a hydrogen atom, a halogen atom (fluorine atom, chlorine atom, etc.), an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkoxy group, an aryloxy group, and a cyano group, respectively. R ₁₁ and R ₁₂ or R ₁₁ and R ₁₃ may combine with each other to form a ring, n is an integer of 1 to 10, and W is a dicyclopentadienyl residue. )
Specific examples of R in —COOR in the ester residue include —CH═CH ₂ , —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ O—CH ₂ CH═CH ₂ , —CH ₂ CH ₂ OCOCH═ _{CH 2, -CH 2 CH 2 OCOC} (CH 3) = CH 2, -CH 2 C (CH 3) = CH 2, -CH 2 CH = CH-C 6 H 5, -CH 2 CH 2 OCOCH = CH- C ₆ H ₅ , —CH ₂ CH ₂ —NHCOO—CH ₂ CH═CH ₂ and —CH ₂ CH ₂ OW (W is a dicyclopentadienyl residue) are included. Specific examples of R in —CONHR in the amide residue include —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ —Z (Z is a 1-cyclohexenyl residue) and —CH ₂ CH ₂ —OCO—CH. = CH ₂ , —CH ₂ CH ₂ —OCO—C (CH ₃ ) ═CH ₂ is included.

  In the dispersant having an ethylenically unsaturated group, a free radical (a polymerization initiation radical or a growth radical of a polymerization process of a polymerizable compound) is added to the unsaturated bond group, and the polymer compound is directly or between molecules. Addition polymerization is carried out through the polymerization chain, and a crosslink is formed between the molecules to cure. Alternatively, atoms in the molecule (for example, hydrogen atoms on carbon atoms adjacent to the unsaturated bond group) are extracted by free radicals to form polymer radicals that are bonded together to form a bridge between the molecules. Harden.

  Examples of the method for introducing a crosslinkable or polymerizable functional group into the side chain include the contents described in JP-A-3-249653. The content ratio of the crosslinkable or polymerizable functional group may constitute all the polymer forming units other than the polar group-containing polymer forming unit, but preferably the formation of the entire polymer as a dispersant. It is 1-70 mass% of a unit, More preferably, the range of 5-50 mass% is mentioned.

The dispersant according to the present invention may be a copolymer with a polymerization component other than a polymerization component containing a polar group-containing polymerization component or a crosslinkable or polymerizable functional group. The applicable polymerization component is not particularly limited as long as it is a monomer copolymerizable with a polar group-containing polymerization component forming a copolymer, a monomer corresponding to a polymerization component having a crosslinkable or polymerizable functional group, It is selected from various viewpoints such as dispersion stability and strength of the formed film. Preferred examples include methacrylates, acrylates, carboxylic acid vinyl esters, (meth) acrylamide and derivatives thereof, styrene and derivatives thereof, acrylonitrile and the like.
As for the ratio of the other polymerization component in a dispersing agent, 5-95 mass% in all the polymerization components is preferable, More preferably, the range of 30-85 mass% is mentioned. Specific examples of the dispersant include, for example, the contents described in paragraph numbers [0023] to [0042] in JP-A No. 11-153703.

A preferred polymerization form of the dispersant of the present invention may be either a random copolymer or a block copolymer as described in JP-A-11-153703, and is not particularly limited.
Furthermore, the AB type is composed of a polymer block (block A) containing a polymerizing component containing a crosslinkable or polymerizable functional group and a polymer block (block B) containing a polymerizing component containing an anionic group. A block, a linear block copolymer of ABA type block, or a graft type block copolymer is preferred. Thus, when the dispersing agent is a linear block copolymer or a graft block copolymer, the dispersibility of the inorganic fine particles and the stability of the dispersion (dispersion stability) are improved, and the high refractive index layer Improvement of the film strength is achieved when the composition for use is a high refractive index layer. This is because the polymer chains are adsorbed in tail form on the inorganic fine particles in the dispersion solvent, which facilitates the adsorption of the polymer to the inorganic fine particles, and facilitates the curing reaction of the polymer block A. Inferred

  The linear block copolymer as described above can be produced by a conventionally known living polymerization reaction method. For the synthesis of AB type and ABA type block copolymers, ion polymerization reaction (for example, organometallic compounds (eg, alkyllithiums, lithium diisopropylamide, alkylmagnesium halides, etc.), hydrogen iodide / iodine series, etc.), porphyrin metal Photopolymerization reaction catalyzed by a complex, group transfer polymerization reaction, known so-called living polymerization reaction such as polymerization reaction under light irradiation using a compound containing a dithiocarbamate group and / or a compound containing a xanthate group as an initiator Is mentioned.

  Specifically, for example, P.I. Lutz, P.M. Masson et al., Polym. Bull. 12.79 (1984), B.I. C. Anderson, G.M. D. Andrews et al, Macromolecules, 14, 1601 (1981), Koichi Right-hand, Koichi Hatada, Polymer Processing, 36, 366 (1987), Toshinobu Higashimura, Mitsuo Sawamoto, Polymer Thesis, 46, 189 (1989), M. et al. Kuroki, T .; Aida, J .; Am. Chem. Soc. 109, 4737 (1987), D.C. Y. Soghah, W.H. R. Hertler et al., Macromolecules, 20, 1473 (1987), Takayuki Otsu, Polymer, 37, 248 (1988), Shunichi Sasamori, Ryuichi Otsu, Polym. Rep. Jap. 37.3508 (1988) etc., and the method of synthesize | combining is mentioned.

  Also, a method of synthesizing a graft copolymer by radical polymerization reaction using a monofunctional macromonomer (the synthesis method of monofunctional macromonomer is Yoshiki Nakajo, Yuya Yamashita “Dye and Drug”, 30, 232 (1985 ), Akira Ueda, Susumu Nagai “Chemistry and Industry”, 60, 57 (1986), PF Rempp & E. Franta, Advances in Polymer Science, 58, 1 (1984), etc. And a method of synthesizing an AB type block copolymer by radical polymerization using an azobis polymer initiator (Akira Ueda, Susumu Nagai “Chemical and Industrial”, 60, 57 (1986), etc.).

  The amount of the dispersant used relative to the inorganic fine particles is preferably in the range of 1 to 100% by mass, more preferably 3 to 50% by mass, and most preferably 5 to 40% by mass. Two or more dispersants may be used in combination.

[Distributed media]
In the present invention, the inorganic fine particles are preferably wet-dispersed, and the dispersion medium used for the wet dispersion can be appropriately selected from water and organic solvents, and is preferably a liquid having a boiling point of 50 ° C. or higher. Is more preferably an organic solvent in the range of 60 ° C to 180 ° C.
The dispersion medium is preferably used in such a proportion that the total dispersion composition containing the inorganic fine particles and the dispersant is 5 to 50% by mass, and more preferably 10 to 30% by mass. Within this range, the dispersion easily proceeds, and the resulting dispersion is preferable because it has a viscosity range with good workability.

  Examples of the dispersion medium include alcohols, ketones, ester amides, ethers, ether esters, hydrocarbons, halogenated hydrocarbons and the like. Specifically, alcohol (for example, methanol, ethanol, propanol, butanol, benzyl alcohol, ethylene glycol, propylene glycol, ethylene glycol monoacetate, etc.), ketone (for example, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methylcyclohexanone, etc.), Esters (eg, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl formate, propyl formate, butyl formate, ethyl lactate, etc.), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methyl Chloroform, etc.), aromatic hydrocarbons (eg, benzene, toluene, xylene, etc.), amides (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone, etc.), ethers For example, dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, etc.), ether alcohols (e.g., 1-methoxy-2-propanol, ethyl cellosolve, methyl carbinol and the like). Two or more of them may be mixed and used. Preferred dispersion media include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol. A coating solvent system mainly comprising a ketone solvent (for example, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.) is also preferably used, and the content of the ketone solvent is 10% by mass of the total solvent contained in the composition for a high refractive index layer. The above is preferable. Preferably it is 30 mass% or more, More preferably, it is 60 mass% or more.

[Making inorganic fine particles into ultrafine particles]
The composition for a high refractive index layer of the present invention is an ultrafine particle dispersion of an inorganic compound having an average particle size of 150 nm or less, whereby the stability of the liquid of the composition is improved. In the high refractive index layer formed from the above, inorganic fine particles are uniformly dispersed in an ultrafine particle state in the matrix of the high refractive index layer, and a transparent high refractive index layer having uniform optical properties is achieved. The size of the ultrafine particles present in the matrix of the high refractive index layer is preferably in the range of an average particle size of 3 to 150 nm, more preferably 5 to 100 nm. In particular, 10 to 80 nm is most preferable.
Furthermore, it is preferable that large particles having an average particle diameter of 500 nm or more are not included, and it is particularly preferable that large particles having an average particle diameter of 300 nm or more are not included. Thereby, the above-mentioned specific uneven | corrugated shape can form the high refractive index layer surface, and it is preferable.

In order to disperse the high refractive index inorganic particles in the size of ultrafine particles not including coarse particles in the above range, a wet dispersion method using a medium having an average particle diameter of less than 0.8 mm together with the dispersant. This is achieved only when dispersed.
Examples of the wet disperser include conventionally known ones such as a sand grinder mill (eg, a bead mill with pins), a dyno mill, a high-speed impeller mill, a pebble mill, a roller mill, an attritor, and a colloid mill. In particular, a sand grinder mill, a dyno mill, and a high-speed impeller mill are preferable for dispersing the oxide fine particles of the present invention in ultrafine particles.

As the media used together with the disperser, the average particle size is less than 0.8 mm, and when the average particle size is within this range, the inorganic fine particle size is 100 nm or less and the particle size is uniform. Fine particles can be obtained. The average particle diameter of the media is preferably 0.5 mm or less, more preferably 0.05 to 0.3 mm.
Further, beads are preferred as the media used for wet dispersion. Specific examples include zirconia beads, glass beads, ceramic beads, steel beads, and the like. Zirconia beads are particularly preferred.
The dispersion temperature in the dispersion step is preferably 20 to 60 ° C, more preferably 25 to 45 ° C. When dispersed in the ultrafine particles at a temperature in this range, re-aggregation and precipitation of the dispersed particles do not occur. This is presumably because the dispersant is appropriately adsorbed on the inorganic fine particles and does not cause poor dispersion stability due to desorption of the dispersant from the particles at room temperature.

Only in such a range, a high refractive index film excellent in refractive index uniformity, film strength, adhesion to an adjacent layer, etc. without impairing transparency can be formed.
Moreover, you may implement a preliminary dispersion process before the said wet dispersion | distribution process. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder.
Furthermore, in order to remove coarse aggregates in the dispersion, the dispersion particles in the dispersion satisfy the above-mentioned range of the average particle diameter and the monodispersibility of the particle diameter. It is also preferable to arrange the filter medium so as to be microfiltered. The filter medium for microfiltration preferably has a filtration particle size of 25 μm or less. The type of filter medium for microfiltration is not particularly limited as long as it has the above performance, and examples thereof include a filament type, a felt type, and a mesh type. The material of the filter medium for finely filtering the dispersion is not particularly limited as long as it has the above-described performance and does not adversely affect the coating solution. Examples thereof include stainless steel, polyethylene, polypropylene, and nylon.

[Matrix of high refractive index layer]
The high refractive index layer contains at least high refractive index inorganic ultrafine particles and a matrix.
According to a preferred embodiment of the present invention, the matrix of the high refractive index layer is at least selected from 1) an organic binder, or 2) an organometallic compound containing a hydrolyzable functional group, and a partial condensate of this organometallic compound. It is formed by curing a high refractive index layer-forming composition containing any of the components after coating.

1) Organic binder
(A) a conventionally known thermoplastic resin;
(B) A combination of a conventionally known reactive curable resin and a curing agent and / or a polymerization accelerator, or (c) a binder precursor (such as a curable polyfunctional monomer or polyfunctional oligomer described later) and a polymerization initiator. In combination with
The binder formed from is mentioned.

(B), (b) or (c) binder forming component, and a high refractive index specific oxide or specific double oxide inorganic fine particles (hereinafter also referred to as high refractive index composite oxide fine particles); A coating composition for forming a high refractive index layer is prepared from a dispersion containing a dispersant. After coating the coating composition on a transparent support to form a coating film, the coating composition is cured by a method according to the binder forming component used, whereby a high refractive index layer is formed. The curing method is appropriately selected depending on the type of the binder component. For example, the curability of the reactive curable resin, the curable polyfunctional monomer, the polyfunctional oligomer, or the like by at least one of means such as heating and light irradiation. Examples thereof include a method for causing a crosslinking reaction or a polymerization reaction in the compound. Especially, the method of forming the binder which hardened | cured the crosslinking reaction or the polymerization reaction of the curable compound by irradiating light using the combination of said (c) is preferable.
Furthermore, it is preferable to carry out a crosslinking reaction or a polymerization reaction with the dispersant contained in the dispersion liquid of the high refractive index composite oxide fine particles simultaneously with or after the application of the coating composition for forming the high refractive index layer.

  The binder in the high refractive index layer produced in this way is dispersed in the binder by, for example, crosslinking or polymerization reaction between the above-described dispersant and a curable polyfunctional monomer or polyfunctional oligomer that is a precursor of the binder. The anionic group of the agent is incorporated. Furthermore, since the binder in the cured film has the function of maintaining the dispersed state of the inorganic fine particles, the structure formed by the crosslinking or polymerization reaction gives the binder film-forming ability and high refraction. It is possible to improve the physical strength, chemical resistance, and weather resistance in a cured film containing fine inorganic compound fine particles.

Examples of the thermoplastic resin mentioned in (a) above include polystyrene resin, polyester resin, cellulose resin, polyether resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl copolymer resin, polyacrylic resin, poly Examples thereof include methacrylic resin, polyolefin resin, urethane resin, silicon resin, and imide resin.
As the reactive curable resin mentioned in (b) above, it is preferable to use a thermosetting resin and / or an ionizing radiation curable resin. Thermosetting resins include phenolic resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea co-condensation resin, silicon resin, polysiloxane Examples thereof include resins. Examples of ionizing radiation curable resins include radical polymerizable unsaturated groups ((meth) acryloyloxy groups, vinyloxy groups, styryl groups, vinyl groups, etc.) and / or cationic polymerizable groups (epoxy groups, thioepoxy groups, vinyloxy groups). , Oxetanyl group, etc.), for example, relatively low molecular weight polyester resin, polyether resin, (meth) acrylic resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin, polybutadiene resin, polythiol Examples include polyene resins.

  As needed for these reactive curable resins, crosslinking agents (epoxy compounds, polyisocyanate compounds, polyol compounds, polyamine compounds, melamine compounds, etc.), polymerization initiators (azobis compounds, organic peroxide compounds, organic halogen compounds) In addition, conventionally known compounds such as curing agents such as UV photoinitiators such as onium salt compounds and ketone compounds) and polymerization accelerators (organic metal compounds, acid compounds, basic compounds, etc.) are used. Specific examples include compounds described by Fuzo Yamashita and Tosuke Kaneko “Crosslinking Agent Handbook” (published by Taiseisha, 1981).

Hereinafter, a binder obtained by crosslinking or polymerizing a curable compound by light irradiation using a combination of the above (c), which is a more preferable method for forming an organic binder of a matrix of a high refractive index layer in a preferred embodiment of the present invention. A method for forming the film will be mainly described.
The functional group of the photocurable polyfunctional monomer or polyfunctional oligomer that undergoes crosslinking or polymerization reaction upon irradiation with light used for the binder precursor may be either radically polymerizable or cationically polymerizable.

Examples of the radical polymerizable group include ethylenically unsaturated groups such as a (meth) acryloyl group, a vinyloxy group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable.
It is preferable to contain a polyfunctional monomer containing two or more radically polymerizable groups in the molecule.
The radical polymerizable polyfunctional monomer is preferably selected from compounds having at least two terminal ethylenically unsaturated bonds. Preferably, it is a compound having 2 to 6 terminal ethylenically unsaturated bonds in the molecule. Such a compound group is widely known in the polymer material field, and these can be used without particular limitation in the present invention. These can have chemical forms such as, for example, monomers, prepolymers, ie dimers, trimers and oligomers, or mixtures thereof and copolymers thereof.

  Examples of radically polymerizable monomers include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), esters and amides thereof, preferably Examples thereof include polymerizable esters of unsaturated carboxylic acids and aliphatic polyhydric alcohol compounds, and polymerizable amides of unsaturated carboxylic acids and aliphatic polyvalent amine compounds. Also, addition reaction products of unsaturated carboxylic acid esters and amides having a nucleophilic substituent such as hydroxyl group, amino group and mercapto group with monofunctional or polyfunctional isocyanates and epoxies, polyfunctional carboxylic acids. A dehydration condensation reaction product with an acid or the like is also preferably used. A reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an isocyanate group or an epoxy group with a monofunctional or polyfunctional alcohol, amine or thiol is also suitable. As another example, it is also possible to use a group of compounds substituted with unsaturated phosphonic acid, styrene or the like instead of the unsaturated carboxylic acid.

Examples of the aliphatic polyhydric alcohol compound include alkanediol, alkanetriol, cyclohexanediol, cyclohexanetriol, inositol, cyclohexanedimethanol, pentaerythritol, sorbitol, dipentaerythritol, tripentaerythritol, glycerin, diglycerin and the like. Examples of the polymerizable ester (monoester or polyester) of the aliphatic polyhydric alcohol compound and the unsaturated carboxylic acid include compounds described in paragraph numbers [0026] to [0027] of JP-A No. 2001-139663.
Examples of other polymerizable esters include, for example, vinyl methacrylate, allyl methacrylate, allyl acrylate, aliphatic alcohols described in JP-B-46-27926, JP-B-51-47334, and JP-A-57-196231. Esters, those having an aromatic skeleton described in JP-A-2-226149, and those having an amino group described in JP-A-1-165613 are also preferably used.

  Specific examples of polymerizable amides formed from an aliphatic polyvalent amine compound and an unsaturated carboxylic acid include methylene bis- (meth) acrylamide, 1,6-hexamethylene bis- (meth) acrylamide, diethylenetriamine tris ( Examples include meth) acrylamide, xylylene bis (meth) acrylamide, and those having a cyclohexylene structure described in JP-B No. 54-21726.

In addition, a vinylurethane compound containing 2 or more polymerizable vinyl groups in one molecule (Japanese Patent Publication No. 48-41708), urethane acrylates (Japanese Patent Publication No. 2-16765), ethylene oxide skeleton Urethane compounds (Japanese Examined Patent Publication No. Sho 62-39418, etc.), polyester acrylates (Japanese Examined Patent Publication No. Sho 52-30490, etc.)), “Japan Adhesion Association Journal”, 1984, Vol. 20, No. 7, p. Photocurable monomers and oligomers described in 300-308 can also be used.
These radical polymerizable polyfunctional monomers may be used in combination of two or more.

Next, a cationically polymerizable group-containing compound (hereinafter, also referred to as “cationic polymerizable compound” or “cationic polymerizable organic compound”) that can be used for forming the binder of the high refractive index layer will be described.
As the cationically polymerizable compound used in the present invention, any compound that undergoes a polymerization reaction and / or a crosslinking reaction when irradiated with an active energy ray in the presence of an active energy ray-sensitive cationic polymerization initiator can be used. Examples thereof include an epoxy compound, a cyclic thioether compound, a cyclic ether compound, a spiro orthoester compound, and a vinyl hydrocarbon compound. In the present invention, one or more of the cationically polymerizable organic compounds may be used.

  As the cationically polymerizable group-containing compound, the number of cationically polymerizable groups in one molecule is preferably 2 to 10, particularly preferably 2 to 5. The molecular weight of this compound is 3000 or less, Preferably it is the range of 200-2000, Most preferably, the range of 400-1500 is mentioned. If the molecular weight is too small, volatilization in the film forming process becomes a problem, and if it is too large, the compatibility with the composition for forming a high refractive index layer is deteriorated.

Examples of the epoxy compound include aliphatic epoxy compounds and aromatic epoxy compounds.
Examples of aliphatic epoxy compounds include polyglycidyl ethers of aliphatic polyhydric alcohols or alkylene oxide adducts thereof, polyglycidyl esters of aliphatic long-chain polybasic acids, homopolymers and copolymers of glycidyl acrylate and glycidyl methacrylate, and the like. Can do. In addition to the above epoxy compounds, for example, monoglycidyl ethers of higher aliphatic alcohols, glycidyl esters of higher fatty acids, epoxidized soybean oil, butyl epoxystearate, octyl epoxide stearate, epoxidized linseed oil, epoxidized polybutadiene, etc. Can be mentioned. In addition, an epoxy compound having an alicyclic structure can also be used. As the alicyclic epoxy compound, a polyglycidyl ether of a polyhydric alcohol having at least one alicyclic ring, or an unsaturated alicyclic A cyclohexene oxide or cyclopentene oxide-containing compound obtained by epoxidizing a ring-containing compound (for example, cyclohexene, cyclopentene, dicyclooctene, tricyclodecene, etc.) with an appropriate oxidizing agent such as hydrogen peroxide or peracid. Can do.

Examples of the aromatic epoxy compound include mono- or polyglycidyl ethers of mono- or polyhydric phenols having at least one aromatic nucleus or alkylene oxide adducts thereof. As these epoxy compounds, for example, compounds described in paragraphs [0084] to [0086] of JP-A No. 11-242101 and compounds described in paragraphs [0044] to [0046] of JP-A No. 10-158385 are disclosed. Compounds and the like.
The binder in the present invention is preferably cured quickly. Among these epoxy compounds, in view of rapid curability, aromatic epoxy compounds and alicyclic epoxy compounds are preferable, and alicyclic epoxy compounds are particularly preferable. In the present invention, one of the above epoxy compounds may be used alone, but two or more may be used in appropriate combination.

Examples of the cyclic thioether compound include compounds in which the epoxy ring in the above epoxy compound is a thioepoxy ring.
Examples of the cyclic ether compound include compounds containing an oxetanyl group, and specific examples include compounds described in paragraph numbers [0024] to [0025] in JP-A No. 2000-239309. These compounds are preferably used in combination with the epoxy compound.
Examples of the spiro orthoester compound include compounds described in JP 2000-506908 A.

Examples of vinyl hydrocarbon compounds include styrene compounds, vinyl group-substituted alicyclic hydrocarbon compounds (vinylcyclohexane, vinylbicycloheptene, etc.), propenyl compounds (“Journal of PolymerScience: Part A: Polymer Chemistry”, 1994, Vol. 32). , P. 2895, etc.), alkoxyallene compounds (“Journal of Polymer Science: Part A: Polymer Chemistry”, 1995, Vol. 33, p. 2493, etc.), vinyl compounds (“Journal of Polymer Science: : Polymer Chemistry ", 1996, Vol. 34, p. 1015, JP 2002-29162 A, etc.), isopropenyl Compound (Journal ofPolymer Science: Part A: Polymer Chemistry, Vol.34,2051 (1996) described the like) and the like.
Two or more kinds may be used in appropriate combination.

  Moreover, the polyfunctional compound such as the polyfunctional monomer or polyfunctional oligomer of the present invention is a compound containing at least one of each selected from the above radical polymerizable group and cationic polymerizable group in the molecule. preferable. Examples thereof include compounds described in paragraph numbers [0031] to [0052] in JP-A-8-277320, compounds described in paragraph number [0015] in JP-A 2000-191737, and the like. The compounds used in the present invention are not limited to these.

  The compound containing a radical polymerizable group and a compound containing a cationic polymerizable group described above are in a mass ratio of 90:10 to 20: compound containing a radical polymerizable group: compound containing a cationic polymerizable group. It is preferable to contain in the ratio of 80, and it is more preferable to contain in the ratio of 80: 20-30: 70.

Next, the polymerization initiator used in combination with the binder precursor in the combination (c) will be described in detail.
Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator.
The polymerization initiator of the present invention is a compound that generates radicals or acids upon irradiation with light and / or heat. The photopolymerization initiator (L) used in the present invention preferably has a maximum absorption wavelength of 400 nm or less. Thus, the handling can be performed under a white light by setting the absorption wavelength to the ultraviolet region. A compound having a maximum absorption wavelength in the near infrared region can also be used.

First, the compound (L1) that generates radicals will be described in detail.
The compound (L1) that generates radicals preferably used in the present invention refers to a compound that initiates and accelerates polymerization of a compound having a polymerizable unsaturated group by generating radicals by irradiation with light and / or heat.
A known polymerization initiator or a compound having a bond with a small bond dissociation energy can be appropriately selected and used. Moreover, the compound (L1) which generate | occur | produces a radical can be used individually or in combination of 2 or more types.
Examples of the compound (L1) that generates radicals include conventionally known organic peroxide compounds, thermal radical polymerization initiators such as conventionally known azo polymerization initiators, amine compounds (described in Japanese Patent Publication No. 44-20189), Photo radical polymerization initiators such as organic halogen compounds, carbonyl compounds, metallocene compounds, hexaarylbiimidazole compounds, organic boric acid compounds, sulfone compounds, disulfone compounds and the like can be mentioned.

Specific examples of the organic halogen compound include Wakabayashi et al., “Bull Chem. Soc Japan”, 1969, Vol. 42, p. 2924, U.S. Pat. No. 3,905,815, JP-A 63-298339, M.S. P. Examples include compounds described in Hutt, “Journal of Heterocyclic Chemistry”, 1970, Vol. 1, No. 3, etc., and in particular, an oxazole compound substituted with a trihalomethyl group: an S-triazine compound.
More preferably, S-triazine derivatives in which at least one mono-, di-, or trihalogen-substituted methyl group is bonded to the S-triazine ring can be mentioned.

  Examples of other organic halogen compounds include ketones, sulfides, sulfones and nitrogen-containing heterocycles described in paragraphs [0039] to [0048] of JP-A No. 5-27830.

  Examples of the carbonyl compound include “Latest UV Curing Technology”, published by Technical Information Association, 1991, p. 60-62, paragraphs [0015] to [0016] of JP-A-8-134404, and compounds described in paragraphs [0029] to [0031] of JP-A-11-217518, and the like. Benzoin compounds such as hydroxyacetophenone, benzophenone, thioxan, benzoin ethyl ether, benzoin isobutyl ether, benzoic acid ester derivatives such as ethyl p-dimethylaminobenzoate, ethyl p-diethylaminobenzoate, benzyldimethyl ketal, acylphosphine Examples include oxides.

Examples of the organic peroxide compound include compounds described in paragraph [0019] of JP-A No. 2001-139663.
Examples of the metallocene compound include various titanocene compounds described in JP-A-2-4705 and JP-A-5-83588, iron-arene complexes described in JP-A-1-304453, JP-A-1-152109, and the like. Is mentioned.

  Examples of the hexaarylbiimidazole compound include various compounds described in JP-B-6-29285, US Pat. No. 3,479,185, US Pat. No. 4,311,783, US Pat. No. 4,622,286, and the like. It is done.

Examples of the organic borate compound include, for example, Japanese Patent No. 2764769, Japanese Patent Application Laid-Open No. 2002-116539, and Kunz, Martin, “Rad Tech'98. Proceeding April 19-22, 1998, Chicago”. Examples of the organic borate described are the compounds described. Examples thereof include compounds described in paragraph numbers [0022] to [0027] of JP-A-2002-116539.
As other organic boron compounds of the above organic borate compounds, JP-A-6-348011, JP-A-7-128785, JP-A-7-140589, JP-A-7-306527, JP-A-7- Specific examples include organoboron transition metal coordination complexes and the like described in Japanese Patent No. 292014.

Examples of the sulfone compound include compounds described in JP-A-5-239015, and examples of the disulfone compound include those represented by general formulas (II) and (III) described in JP-A 61-166544. Compounds and the like.
These radical generating compounds (L1) may be used alone or in combination of two or more. The amount added is 0.1 to 30% by mass, preferably 0.5 to 25% by mass, and particularly preferably 1 to 20% by mass with respect to the total amount of the compound containing a radical polymerizable group. Within this range, there is no problem in the temporal stability of the composition for a high refractive index layer, and high polymerizability is preferable.

Next, the acid generator (L2) that can be used as the photopolymerization initiator (L) will be described in detail.
Examples of the acid generator (L2) include a known compound such as a photo-initiator for photocationic polymerization, a photo-decoloring agent for dyes, a photo-discoloring agent, or a known acid generator used for a microresist. A mixture thereof may be mentioned.
Examples of the acid generator (L2) include organic halogen compounds and disulfone compounds. Specific examples of these organic halogen compounds and disulfone compounds are the same as those described for the compound (L1) that generates radicals.
An onium salt can also be used as the acid generator (L2). Examples of the onium salt include diazonium salts, ammonium salts, iminium salts, phosphonium salts, iodonium salts, sulfonium salts, arsonium salts, and selenonium salts. Examples include the compounds described in paragraph numbers [0058] to [0059] of Kai 2002-29162.

  In the present invention, the acid generator (L2) that is particularly preferably used includes onium salts. Among them, diazonium salts, iodonium salts, sulfonium salts, and iminium salts are used for photosensitivity at the start of photopolymerization, and material stability of the compound. From the point of property etc., it is preferable.

  Specific examples of onium salts that can be suitably used in the present invention include, for example, an amylated sulfonium salt described in paragraph [0035] of JP-A-9-268205 and JP-A-2000-71366. Diaryl iodonium salts or triaryl sulfonium salts described in paragraphs [0010] to [0011], sulfonium salts of thiobenzoic acid S-phenyl ester described in paragraph [0017] of JP 2001-288205, JP Examples include the onium salts described in paragraph numbers [0030] to [0033] of Japanese Patent Application Laid-Open No. 2001-133696.

Other examples of the acid generator (L2) include organic metal / organic halides described in JP-A-2002-29162, paragraphs [0059] to [0062], and light having an o-nitrobenzyl type protecting group. Examples of the acid generator include compounds such as compounds (iminosulfonate, etc.) that generate sulfonic acid by photolysis.
These acid generators (L2) may be used alone or in combination of two or more. The addition amount of these acid generators is 0.1 to 20% by mass, preferably 0.5 to 15% by mass, particularly preferably 1 in terms of the total mass of 100 parts by mass of the compound containing all cationically polymerizable groups. The range of 10 mass% is mentioned. Within the above range, the composition for the high refractive index layer has high stability, which is preferable from the viewpoint of polymerization reactivity.

The composition for a high refractive index layer of the present invention comprises a compound (L1) that generates a radical as a polymerization initiator with respect to the total mass of a compound containing a radical polymerizable group and a compound containing a cationic polymerizable group. It is preferable to contain 0.5-10 mass% and a cationic polymerization initiator in the ratio of 1-10 mass%. A more preferable content ratio includes a range of 1 to 5% by mass of the compound (L1) that generates radicals and a range of 2 to 6% by mass of the cationic polymerization initiator.
In the composition for a high refractive index layer of the present invention, a conventionally known ultraviolet spectral sensitizer and chemical sensitizer may be used in combination when the polymerization reaction is carried out by ultraviolet irradiation. Examples include Michler's ketone, amino acids (such as glycine), and organic amines (such as butylamine and dibutylamine).

Moreover, when performing a polymerization reaction by near infrared irradiation, it is preferable to use a near infrared spectral sensitizer together.
The near-infrared spectral sensitizer used in combination may be a light-absorbing substance having an absorption band in at least a part of the wavelength region of 700 nm or more, and a compound having a molecular extinction coefficient of 10,000 or more is preferable. Furthermore, the absorption is preferably in the range of 750 to 1400 nm and the molecular extinction coefficient is preferably 20000 or more. Moreover, it is more preferable that there is a trough of absorption in the visible light wavelength region of 420 nm to 700 nm, and it is optically transparent. As the near-infrared spectral sensitizer, various pigments and dyes known as near-infrared absorbing pigments and near-infrared absorbing dyes can be used. Among these, it is preferable to use a conventionally known near-infrared absorber.

  Commercial dyes and literature (for example, “Near Infrared Absorbing Dye”, Chemical Industry, 1986, May, p. 45-51, “Development and Market Trends of Functional Dyes in the 90s”, CMC Corporation, 1990, Chapter 2, Section 2.3), edited by Ikemori and Piladani, “Special Function Dye”, CMC Co., 1986, J. Am. FABIAN, “Chem. Rev.”, 1992, 92, pp. 1197-1226, a catalog published in 1995 by Nippon Sensitive Dye Research Institute, Exciton Inc. Known dyes described in the laser dye catalog or patent issued in 1989.

2) Organometallic compound containing a hydrolyzable functional group and a partial condensate of this organometallic compound As a matrix of the high refractive index layer used in the present invention, an organometallic compound containing a hydrolyzable functional group is used. It is also preferable to form a cured film after forming the coating film by a sol-gel reaction. Examples of the organometallic compound include compounds composed of Si, Ti, Zr, Al and the like. Examples of the hydrolyzable functional group include an alkoxy group, an alkoxycarbonyl group, a halogen atom, and a hydroxyl group, and an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group is particularly preferable.
A preferred organometallic compound is an organosilicon compound represented by the following general formula (1) and a partial hydrolyzate (partial condensate) thereof. In addition, it is a fact well known to those skilled in the art that the organosilicon compound represented by the general formula (1) is easily hydrolyzed and subsequently undergoes a dehydration condensation reaction.

General formula (1): (R ^a ) _m —Si (X) _n
In General Formula (1), R ^a represents a substituted or unsubstituted aliphatic group having 1 to 30 carbon atoms or an aryl group having 6 to 14 carbon atoms. X represents a halogen atom (a chlorine atom, a bromine atom, etc.), an OH group, an OR ^b group, or an OCOR ^b group. Here, R ^b represents a substituted or unsubstituted alkyl group. m represents an integer of 0 to 3. n represents an integer of 1 to 4. The sum of m and n is 4. However, when m is 0, X represents an OR ^b group or an OCOR ^b group.
In the general formula (1), the aliphatic group represented by ^Ra preferably has 1 to 18 carbon atoms (for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, hexadecyl, octadecyl, benzyl group, Phenethyl group, cyclohexyl group, cyclohexylmethyl, hexenyl group, decenyl group, dodecenyl group, etc.). More preferably, it has 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms.
^Examples of the aryl group for R ^a include phenyl, naphthyl, anthranyl, and the like, and is preferably a phenyl group.

  Although there is no restriction | limiting in particular as a substituent, Halogen (fluorine, chlorine, bromine, etc.), a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an 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.), alkoxysilyl groups (trimethoxysilyl, triethoxysilyl etc.), acyloxy groups (acetoxy, (meth) acryloyl etc.), alkoxy Carbonyl group (methoxycarbonyl, ethoxycarbonyl) Bonyl etc.), aryloxycarbonyl group (phenoxycarbonyl etc.), carbamoyl group (carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-methyl-N-octylcarbamoyl etc.), acylamino group (acetylamino, benzoylamino) , Acrylicamino, methacrylamino and the like).

  Among these substituents, more preferred are a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group, an alkoxysilyl group, an acyloxy group, and an acylamino group, and particularly preferred are an epoxy group and a polymerizable acyloxy group ((meta ) Acryloyl), a polymerizable acylamino group (acrylamino, methacrylamino). These substituents may be further substituted.

R ^b represents substituted or unsubstituted alkyl. The explanation of the substituent in the alkyl group is the same as R ^a .
m represents an integer of 0 to 3. n represents an integer of 1 to 4. The sum of m and n is 4. m is preferably 0, 1, 2 and particularly preferably 1. When m is 0, X represents an OR ^b group or an OCOR ^b group.
As for content of the compound of General formula (1), 10-80 mass% of the total solid of a high refractive index layer is preferable, More preferably, it is 20-70 mass%, Most preferably, it is 30-50 mass%.

  Specific examples of the compound of the general formula (1) include compounds described in paragraph numbers [0054] to [0056] of JP-A No. 2001-166104.

In the high refractive index layer, the organic binder preferably has a silanol group. When the binder has a silanol group, the physical strength, chemical resistance, and weather resistance of the high refractive index layer are further improved.
A silanol group is, for example, a binder precursor (such as a curable polyfunctional monomer or polyfunctional oligomer), a polymerization initiator, a high refractive index inorganic fine particle as a binder forming component constituting a coating composition for forming a high refractive index layer. An organic silicon compound represented by the general formula (1) having a crosslinkable or polymerizable functional group is blended in the coating composition together with a dispersant contained in the dispersion liquid, and the coating composition is formed on the transparent support. The dispersant, the polyfunctional monomer, the polyfunctional oligomer, and the organosilicon compound represented by the general formula (1) can be introduced into the binder by crosslinking reaction or polymerization reaction.

  The hydrolysis / condensation reaction for curing the organometallic compound is preferably 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, trifluoroacetic acid, methanesulfonic acid and toluenesulfonic acid, inorganic bases such as sodium hydroxide, potassium hydroxide and ammonia , Organic bases such as triethylamine and pyridine, metal alkoxides such as triisopropoxyaluminum, tetrabutoxyzirconium and tetrabutoxytitanate, metal chelate compounds such as β-diketones or β-ketoesters, and the like. Specifically, for example, compounds described in paragraph numbers [0071] to [0083] in JP-A No. 2000-275403 are exemplified.

  The ratio of these catalyst compounds in the coating composition is 0.01 to 50% by weight, preferably 0.1 to 50% by weight, more preferably 0.5 to 10% by weight, based on the organometallic compound. A range is mentioned. The reaction conditions are preferably adjusted as appropriate depending on the reactivity of the organometallic compound.

  In the high refractive index layer, the matrix preferably has a specific polar group. Specific polar groups include anionic groups, amino groups, and quaternary ammonium groups. Specific examples of the anionic group, amino group and quaternary ammonium group are the same as those described for the dispersant.

  The matrix of the high refractive index layer having a specific polar group is formed by, for example, blending a dispersion containing high refractive index inorganic fine particles and a dispersant in a coating composition for forming a high refractive index layer to form a high refractive index layer. As a component, a binder precursor having a specific polar group (such as a curable polyfunctional monomer or polyfunctional oligomer having a specific polar group) and a polymerization initiator and a specific polar group, and having crosslinking or polymerization At least one of the organosilicon compounds represented by the general formula (1) having a functional functional group, and a monofunctional monomer having a specific polar group and a crosslinkable or polymerizable functional group, if desired, The coating composition is coated on a transparent support to crosslink the dispersant, monofunctional monomer, polyfunctional monomer or polyfunctional oligomer and / or the organosilicon compound represented by the general formula (1). Obtained by the polymerizing reaction.

The monofunctional monomer having a specific polar group functions as a dispersion aid for inorganic fine particles in the coating composition. Furthermore, after coating, a uniform dispersion of inorganic fine particles in the high refractive index layer is maintained by using a binder, a crosslinking reaction or a polymerization reaction with a dispersant, a polyfunctional monomer or polyfunctional oligomer, and a physical reaction. A high refractive index layer excellent in strength, chemical resistance and weather resistance can be produced.
The use amount of the monofunctional monomer having an amino group or a quaternary ammonium group with respect to the dispersant is preferably 0.5 to 50% by mass, more preferably 1 to 30% by mass. If the binder is formed by crosslinking or polymerization reaction at the same time or after the application of the high refractive index layer, the monofunctional monomer can effectively function before the application of the high refractive index layer.

Further, the matrix of the high refractive index layer of the present invention includes a material cured and formed from an organic polymer containing a conventionally known crosslinking or polymerizable functional group, which corresponds to the above-mentioned organic binder (a). The polymer after the formation of the high refractive index layer preferably has a structure that is further crosslinked or polymerized. Examples of such polymers include polyolefins (consisting of saturated hydrocarbons), polyethers, polyureas, polyurethanes, polyesters, polyamines, polyamides and melamine resins. Among these, polyolefin, polyether and polyurea are preferable, and polyolefin and polyether are more preferable. The mass average molecular weight of the organic polymer before curing is preferably 1 × 10 ³ to 1 × 10 ⁶ , more preferably 3 × 10 ³ to 1 × 10 ⁵ .

The organic polymer before curing is preferably a copolymer having a repeating unit having a specific polar group as described above and a repeating unit having a crosslinked or polymerized structure. The ratio of the repeating unit having an anionic group in the polymer is preferably 0.5 to 99% by mass, more preferably 3 to 95% by mass, and more preferably 6 to 90% by mass in all repeating units. Most preferred. The repeating unit may have two or more anionic groups which may be the same or different.
When the repeating unit having a silanol group is included, the ratio is preferably 2 to 98 mol%, more preferably 4 to 96 mol%, and most preferably 6 to 94 mol%.
When the repeating unit having an amino group or a quaternary ammonium group is included, the proportion is preferably 0.1 to 50% by mass, and more preferably 0.5 to 30% by mass.

In addition, even if the silanol group, amino group, and quaternary ammonium group are contained in a repeating unit having an anionic group or a repeating unit having a crosslinked or polymerized structure, the same effect can be obtained.
The ratio of the repeating unit having a crosslinked or polymerized structure in the polymer is preferably 1 to 90% by mass, more preferably 5 to 80% by mass, and most preferably 8 to 60% by mass.

  The matrix formed by crosslinking or polymerizing the binder is preferably formed by applying a coating composition for forming a high refractive index layer on a transparent support and performing crosslinking or polymerization reaction simultaneously with or after application.

[Other compositions of high refractive index layer]
In the high refractive index layer of the present invention, other compounds can be appropriately added depending on applications and purposes. For example, 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, and the high refractive index layer includes an aromatic ring and a halogen other than fluorine. When an atom such as a chemical element (for example, Br, I, Cl, etc.), S, N, P or the like is contained, the refractive index of the organic compound is increased. The binder to be used can also be preferably used.

  In addition to the above-mentioned components (inorganic fine particles, polymerization initiators, sensitizers, etc.), the high refractive index layer includes resins, surfactants, antistatic agents, coupling agents, thickeners, anti-coloring agents, and coloring agents. (Pigments, dyes), antifoaming agents, leveling agents, flame retardants, ultraviolet absorbers, infrared absorbers, adhesion promoters, polymerization inhibitors, antioxidants, surface modifiers, conductive metal fine particles, etc. are added. You can also. These components can be used in the range of 0.01 to 20% by mass in the total composition.

<Formation of high refractive index layer>
The high refractive index layer is preferably constructed by applying the above-described coating solution for the high refractive index layer directly on the transparent support described later or via another layer.
The coating liquid for the high refractive index layer of the present invention is obtained by mixing and diluting a specific inorganic compound ultrafine particle dispersion, a matrix binder liquid, and an additive used as necessary to a coating dispersion medium to a predetermined concentration. Adjusted.

The coating solution used for coating is preferably filtered before coating. As a filter for filtration, it is preferable to use a filter having a pore diameter as small as possible within a range in which components in the coating solution are not removed. For the filtration, a filter having an absolute filtration accuracy of 0.1 to 100 μm is used, and a filter having an absolute filtration accuracy of 0.1 to 25 μm is preferably used. The thickness of the filter is preferably 0.1 to 10 mm, and more preferably 0.2 to 2 mm. In that case, it is preferable to perform filtration at a filtration pressure of 15 kgf / cm ² or less, more preferably 10 kgf / cm ² or less, and further 2 kgf / cm ² or less.
The filtration filter member is not particularly limited as long as it does not affect the coating solution. Specifically, the same thing as the filter member of the wet dispersion of an inorganic compound mentioned above is mentioned.
It is also preferable to ultrasonically disperse the filtered coating solution immediately before coating to assist defoaming and dispersion holding of the dispersion.

  In the present invention, the high refractive index layer is a dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating, and the like. It can be produced by applying a known thin film forming method such as a coating method, a gravure coating method, a micro gravure coating method or an extrusion coating method, followed by drying, light and / or heat irradiation. Preferably, curing by light irradiation is advantageous from rapid curing. Furthermore, it is also preferable to perform heat treatment in the latter half of the photocuring treatment.

  The light source for light irradiation may be any ultraviolet light region or near-infrared light. Ultraviolet, high pressure, medium pressure, and low pressure mercury lamps, chemical lamps, carbon arc lamps, metal halide lamps may be used as ultraviolet light sources. Xenon lamps, sunlight, etc. Various available laser light sources having a wavelength of 350 to 420 nm may be irradiated as a multi-beam. Further, examples of the near-infrared light source include a halogen lamp, a xenon lamp, and a high-pressure sodium lamp. Various available laser light sources having a wavelength of 750 to 1400 nm may be irradiated in a multi-beam form.

When using a near-infrared light source, it may be used in combination with an ultraviolet light source, or light may be irradiated from the substrate surface side opposite to the high refractive index layer coating side. Film curing in the depth direction in the coating layer proceeds without delay with the vicinity of the surface, and a cured film with a uniform curing state can be obtained. In the case of photo radical polymerization by light irradiation, it can be performed in air or inert gas However, it is preferable to reduce the oxygen concentration as much as possible in order to shorten the polymerization induction period of the radically polymerizable monomer or to sufficiently increase the polymerization rate. The irradiation intensity of the irradiated ultraviolet rays is preferably about 0.1 to 100 mW / cm ² , and the light irradiation amount on the coating film surface is preferably 100 to 1000 mJ / cm ² . Further, the temperature distribution of the coating film in the light irradiation step is preferably as uniform as possible, preferably within ± 3 ° C., and more preferably controlled within ± 1.5 ° C. In this range, the polymerization reaction in the in-plane and in-layer depth directions of the coating film proceeds uniformly, which is preferable.
The film thickness of the high refractive index layer is preferably 30 to 500 nm, and more preferably in the range of 50 to 300 nm. When the high refractive index layer also serves as the hard coat layer, the thickness is preferably 0.5 to 10 μm, more preferably 1 to 7 μm, and particularly preferably 2 to 5 μm.

The high refractive index layer after curing 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, it is preferable that the wear amount of the test piece coated with the high refractive index layer before and after the test is smaller.
The haze of the high refractive index layer is preferably as low as possible. It is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less.

<Low refractive index layer>
The antireflection film of the present invention is formed by sequentially laminating a low refractive index layer on a high refractive index layer provided on a transparent substrate. The refractive index of the low refractive index layer is 1.20 to less than 1.55. Preferably it is 1.30-1.50, Most preferably, it is 1.35-1.48.
It is preferable to construct as the outermost layer having scratch resistance and antifouling property. As means for greatly improving the scratch resistance, imparting slipperiness to the surface is effective, and conventionally known thin film layer means such as introduction of silicone or introduction of fluorine can be applied.

In the present invention, the low refractive index layer is preferably mainly composed of a fluorine-containing compound. In the present invention, “mainly containing a fluorine-containing compound” means that the fluorine-containing compound contained in the outermost layer is 50% by mass or more with respect to the total mass of the outermost layer, and contains 60% by mass or more. More preferably.
The refractive index of the fluorine-containing compound is preferably 1.35 to 1.50. More preferably, it is 1.36-1.47. Moreover, it is preferable that a fluorine-containing compound contains a fluorine atom in 35-80 mass%.
Examples of the fluorine-containing compound include a fluorine-containing polymer, a fluorine-containing surfactant, a fluorine-containing ether, and a fluorine-containing silane compound. Specifically, for example, paragraph numbers [0018] to [0026] of JP-A-9-222503, paragraph numbers [0019] to [0030] of JP-A-11-38202, paragraph number [0027] of JP-A-2001-40284. To [0028] and the like.

As the fluorine-containing polymer, a copolymer having a structure of a repeating unit containing a fluorine atom, a repeating unit containing a crosslinkable or polymerizable functional group, and a repeating unit composed of other substituents is preferable. Examples of the crosslinkable or polymerizable functional group are the same as those described for the high refractive index layer.
As the structure of the other repeating unit of the fluorinated polymer, a hydrocarbon-based copolymer component is preferable in order to obtain solubilization of the coating solvent, and preferably about 50% is introduced into the fluorinated polymer. In this case, it is preferable to combine with a silicone compound.

Examples of the silicone compound include compounds having a polysiloxane structure, and those having a curable functional group or a polymerizable functional group in the polymer chain and having a crosslinked structure in the film are preferable. Examples thereof include reactive silicones such as marketed silaplane (manufactured by Chisso Corporation), compounds containing silanol groups at both ends of the polysiloxane structure described in JP-A-11-258403, and the like.
The crosslinking or polymerization reaction of the fluorine-containing polymer having a crosslinking or polymerizable group is preferably carried out by irradiating or heating the coating composition for forming the outermost layer simultaneously with or after coating. Examples of the polymerization initiator, the sensitizer and the like are the same as those used in the high refractive index layer.

Also preferred is a sol-gel cured film in which a silane coupling agent and a specific fluorine-containing hydrocarbon group-containing silane coupling agent are cured by a condensation reaction in the presence of a catalyst.
For example, polyfluoroalkyl group-containing silane compounds or partially hydrolyzed condensates thereof (compounds described in JP-A-58-142958, JP-A-58-147483, JP-A-58-147484, etc.), JP-A-9-157582 Perfluoroalkyl group-containing silane coupling agent described in the above publication, silyl compounds containing a poly "perfluoroalkyl ether" group which is a fluorine-containing long chain group (JP 2000-117902 A, JP 2001-48590 A, And the like described in JP-A-2002-53804).

The low refractive index layer contains fillers (for example, inorganic fine particles and organic fine particles), silane coupling agents, slip agents (silicon compounds such as dimethyl silicon), surfactants and the like as additives other than the above. Can do. In particular, it is preferable to contain inorganic fine particles, a silane coupling agent, and a slip agent.
As the inorganic fine particles, low refractive index compounds such as silicon dioxide (silica) and fluorine-containing particles (magnesium fluoride, calcium fluoride, barium fluoride) are preferable. Particularly preferred is silicon dioxide (silica). The mass average diameter of the primary particles of the inorganic fine particles is preferably 1 to 150 nm, more preferably 3 to 100 nm, and most preferably 1 to 80 nm. The inorganic fine particles are preferably dispersed more finely. The shape of the inorganic fine particles is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape, a short fiber shape, a ring shape, or an indefinite shape.

The low refractive index layer of the present invention preferably has a surface dynamic friction coefficient of 0.25 or less. The dynamic friction coefficient described here refers to a dynamic friction coefficient between a surface and a stainless hard sphere having a diameter of 5 mm when a load of 0.98 N is applied to a stainless hard sphere having a diameter of 5 mm and the surface is moved at a speed of 60 cm / min. Preferably it is 0.17 or less, Most preferably, it is 0.15 or less.
Further, the contact angle with water on the outermost surface is preferably 90 ° or more. More preferably, it is 95 ° or more, and particularly preferably 100 ° or more.
When the low refractive index layer is located below the outermost layer, the low refractive index layer may be formed by a vapor phase method (vacuum deposition method, sputtering method, ion plating method, plasma CVD method, etc.). The coating method is preferable because it can be manufactured at a low cost.

The film thickness of the low refractive index layer is preferably 30 to 200 nm, more preferably 50 to 150 nm, and most preferably 60 to 120 nm.
The haze of the low refractive index layer is preferably as low as possible. It is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less.
The strength of the low refractive index layer is preferably H or more, more preferably 2H or more, and most preferably 3H or more in a pencil hardness test according to JIS K5400.
Further, the wear amount, the surface dynamic friction coefficient, and the contact angle with water in the Taber test according to JIS K5400 are preferably the same as those of the uppermost layer.

<Medium refractive index layer>
The antireflection film of the present invention preferably has a two-layer structure in which the high refractive index layers have different refractive indexes. That is, the low refractive index layer formed by coating the composition by the above method is formed on the high refractive index layer having a higher refractive index, adjacent to the high refractive index layer, and has a low refractive index. A three-layer structure in which an intermediate refractive index layer having a refractive index intermediate between the refractive index of the support and the refractive index of the high refractive index layer is formed on the opposite side of the refractive index layer is preferable. As described above, the refractive index of each refractive index layer is relative.
The material constituting the middle refractive index layer of the present invention may be any conventionally known material, but the same material as the above high refractive index layer is preferable. The refractive index is easily adjusted by the type and amount of inorganic fine particles, and a thin layer having a thickness of 30 to 500 nm is formed in the same manner as described in the high refractive index layer. More preferably, the film thickness is 50 to 300 nm.
The medium refractive index layer after curing 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 coated with the medium refractive index layer before and after the test, the better.
The haze of the medium refractive index layer is preferably as low as possible. It is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less.

<Hard coat layer>
The hard coat layer is provided on the surface of the transparent support in order to impart physical strength to the antireflection film. In particular, it is preferably provided between the transparent support and the high refractive index layer.
The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of a light and / or heat curable compound. For example, a coating composition containing a polyester (meth) acrylate, a polyurethane (meth) acrylate, a polyfunctional monomer, a polyfunctional oligomer, or a hydrolyzable functional group-containing organometallic compound is coated on a transparent support, and a curable compound is applied. It can be formed by a crosslinking reaction or a polymerization reaction.

As the curable functional group, a photopolymerizable functional group is preferable, and the organometallic compound containing a hydrolyzable functional group is preferably an organic alkoxysilyl compound. Specifically, the thing of the same content as the matrix binder of a high refractive index layer is mentioned.
The hard coat layer preferably contains inorganic fine particles having an average primary particle size of 300 nm or less. More preferably, it is 10-150 nm, More preferably, it is 20-100 nm. 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.

The inorganic fine particles have functions of increasing the hardness of the hard coat layer and suppressing curing shrinkage of the coating layer. It is also added for the purpose of controlling the refractive index of the hard coat layer.
Specific examples of the composition of the hard coat layer include those described in JP 2002-144913, 2000-9908, WO 00/46617, and the like.

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 with respect to the total mass of the hard coat layer.
As described above, the high refractive index layer can also serve as a hard coat layer. When the high refractive index layer also serves as the hard coat layer, it is preferably formed by finely dispersing inorganic fine particles using the technique described for the high refractive index layer and incorporating it into 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.
Moreover, in the Taber test according to JIS K5400, the smaller the amount of wear of the test piece before and after the test, the better.

<Other layers>
The laminated antireflection film may further be provided with a moisture proof layer, an antistatic layer, a primer layer, an undercoat layer, a protective layer, a shield layer, and a sliding layer. The shield layer is provided to shield electromagnetic waves and infrared rays.

<Transparent support>
Unless the antireflection film is directly provided on the CRT image display surface or the lens surface, the antireflection film preferably has a transparent support (also referred to as a transparent substrate). As the transparent support, a plastic film is preferable to a glass plate.

  Examples of plastic film materials include cellulose esters (eg, triacetyl cellulose, diacetyl cellulose, propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose, nitrocellulose), polyamides, polycarbonates, polyesters (eg, polyethylene terephthalate, polyethylene naphthalate). , Poly-1,4-cyclohexanedimethylene terephthalate, polyethylene-1,2-diphenoxyethane-4,4′-dicarboxylate, polybutylene terephthalate), polystyrene (eg, syndiotactic polystyrene), polyolefin (eg, Polypropylene, polyethylene, polymethylpentene), polysulfone, polyethersulfone, polyarylate, polyetherimide, polymethylmethene Tacrylate and polyether ketone are included. Triacetyl cellulose, polycarbonate, polyethylene terephthalate and polyethylene naphthalate are preferred.

The light transmittance of the transparent support is preferably 80% or more, and more preferably 86% or more. The haze of the transparent support is preferably 2.0% or less, and more preferably 1.0% or less. The refractive index of the transparent support is preferably 1.4 to 1.7. An infrared absorber or an ultraviolet absorber may be added to the transparent support. The addition amount of the infrared absorber is preferably 0.01 to 20% by mass of the transparent support, and more preferably 0.05 to 10% by mass. As a slip agent, particles of an inert inorganic compound may be added to the transparent support. Examples of the inorganic _{compound, SiO 2, TiO 2, BaSO} 4, CaCO 3, talc and kaolin. Surface treatment may be performed on the transparent support.

  Examples of surface treatment include chemical treatment, mechanical treatment, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, ozone oxidation treatment, mixed acid treatment, alkali saponification treatment, etc. Is included. Glow discharge treatment, ultraviolet irradiation treatment, corona discharge treatment, flame treatment and alkali saponification treatment are preferred, and glow discharge treatment, ultraviolet treatment and alkali saponification treatment are more preferred.

<Formation of antireflection film>
Each layer of the multilayer antireflection film is formed by a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method or an extrusion coating method (described in US Pat. No. 2,681,294). , Can be formed by coating. Two or more layers may be applied simultaneously. Regarding the method of simultaneous application, the specifications of US Pat. Nos. 2,761,789, 2,941,898, 3,508,947, and 3,526,528 and Yuji Harasaki, “Coating Engineering”, Asakura Shoten 1973, p. 253.

In the antireflection film of the present invention, at least the high refractive index layer and the low refractive index layer are laminated, so that bright spot defects are easily noticeable when foreign matters such as dust and dust are present. The bright spot defect in the present invention is a defect that can be seen by reflection on the coating film as described above, and can be detected by an operation such as black coating on the back surface of the antireflection film after coating. The bright spot defects that can be visually observed are generally 50 μm or more. When there are many bright spot defects, the yield at the time of manufacture will fall and a large-area antireflection film cannot be manufactured.
In the antireflection film of the present invention, the number of bright spot defects is 20 or less per square meter, preferably 10 or less, more preferably 5 or less, and particularly preferably 1 or less.

  In order to continuously produce the antireflection film of the present invention, a step of continuously feeding a roll-shaped transparent support film (hereinafter also referred to as a film support), a step of applying and drying a coating liquid, A step of curing and a step of winding up the film support having the cured layer are performed.

The film support is continuously sent out from the roll-shaped film support to the clean room. In the clean room, the static electricity charged on the film support is removed by an electrostatic charge-off device, and then the film support adheres on the film support. Remove the foreign material that has been removed with a dust remover. Subsequently, the coating liquid is applied onto the film support in the application section installed in the clean room, and the applied film support is sent to the drying chamber and dried.
The film support having the dried coating layer is fed from the drying chamber to the radiation curing chamber, and irradiated with radiation, the polymerizable compound and monomer contained in the coating layer are polymerized and cured. Furthermore, the film support having a layer cured by radiation is sent to the thermosetting section and heated to complete the curing, and the film support having the layer that has been completely cured is wound up into a roll shape.
The above steps may be performed every time each layer is formed, or a plurality of coating units-drying chambers-radiation curing units-thermosetting chambers may be provided to continuously form each layer.

  In order to produce an antireflection film with few bright spot defects in the present invention, as described above, it is necessary to precisely control the degree of dispersion of the high refractive index ultrafine particles in the coating material for the high refractive index layer, and Examples include microfiltration operation. At the same time, each layer forming the antireflection layer is formed on the film before the application process in the application unit and the drying process performed in the drying chamber are performed in a high clean air atmosphere and the application is performed. It is preferable that dust and dust are sufficiently removed. The air cleanliness of the coating process and the drying process is desirably class 10 (353 particles / 0.5 m or more / (cubic meter) or less) based on the standard of air cleanliness in the US Federal Standard 209E. Preferably it is class 1 (35.5 particles / (cubic meter) or less) having a particle size of 0.5 μm or more. Moreover, it is more preferable that the degree of air cleanliness is high also in the feeding and winding parts other than the coating-drying process.

  As a dust removal method used in a dust removal step as a pre-process for coating, a method of pressing a nonwoven fabric, a blade or the like against the film surface described in JP-A-59-150571, described in JP-A-10-309553 Highly clean air is blown at a high speed to peel off the deposit from the film surface, and suction is performed at a suction port adjacent to the film. Ultrasonic-vibrated compressed air described in JP-A-7-333613 is sprayed onto the deposit. And a dry dust removal method such as a method of peeling and suctioning (manufactured by Shinkosha, New Ultra Cleaner, etc.). In addition, a method of introducing a film into a cleaning tank and peeling off deposits with an ultrasonic vibrator, supplying a cleaning liquid to the film described in Japanese Patent Publication No. 49-13020, and then blowing and sucking high-speed air As described in JP-A-2001-38306, a wet dust removal method such as a method in which a web is continuously rubbed with a roll wetted with a liquid and then the liquid is sprayed onto the rubbed surface for cleaning. be able to. Among such dust removal methods, a method using ultrasonic dust removal or a method using wet dust removal is particularly preferable in terms of dust removal effect.

  In addition, it is particularly preferable to remove static electricity on the film support before performing such a dust removal step from the viewpoint of increasing dust removal efficiency and suppressing adhesion of dust. As such a static elimination method, a corona discharge ionizer, a light irradiation ionizer such as UV or soft X-ray, or the like can be used. The charged voltage of the film support before and after dust removal and coating is desirably 1000 V or less, preferably 300 V or less, particularly preferably 100 V or less.

<Characteristics of antireflection film>
The lower the reflectance of the antireflection film, the better. Specifically, the average reflectance in the wavelength region of 450 to 650 nm is preferably 2% or less, more preferably 1% or less, and most preferably 0.7% or less. The haze of the antireflection film (when the antiglare function described below is absent) is preferably 3% or less, more preferably 1% or less, and most preferably 0.5% or less.

In the antireflection film of the present invention, the number of bright spot defects is 20 or less per square meter, preferably 10 or less, more preferably 5 or less, and particularly preferably 1 or less.
The strength of the antireflection film is the adhesion between the cured film having a high refractive index and the upper layer (low refractive index layer) coated on the cured film. When the surface irregularities are maintained over a period, the adhesion is stronger. Therefore, the smaller the amount of wear in the Taber abrasion test based on JISK-6902, the stronger the adhesion, and the stronger the antireflection film. The amount of wear in the Taber abrasion test is specifically the value described above for the high refractive index layer. Further, the pencil hardness under a 1 kg load is preferably H or more, more preferably 2H or more, and most preferably 3H or more.

<Weather resistance of high refractive index layer and antireflection film>
In the high refractive index layer and antireflection film of the present invention containing an inorganic compound selected from the above-mentioned “specific oxide” and “specific double oxide” as high refractive index particles, JISK5600-7-7: 1999 The weather resistance by the accelerated weather resistance test will be described. Specifically, the performance after 150 hours of treatment is excellent as shown below.

[High refractive index layer]
The haze after the accelerated weather resistance test is such that the increase is within 10% and the maximum haze does not exceed 3% with respect to the haze before the weather test.

[Antireflection film]
The haze after the accelerated weather resistance test is such that the increase is within 10% and the maximum haze does not exceed 3% with respect to the haze before the weather test. Further, the increase in the amount of wear in the Taber abrasion test based on JISK-6902 is within 10%.
Furthermore, the number of luminance defects having a size of 50 μm or more is 20 or less, preferably 10 or less per square meter.

<Anti-glare property of antireflection film>
The antireflection film used in the present invention can impart antiglare properties by forming irregularities on the surface having the high refractive index layer.
The antiglare property correlates with the average surface roughness (Ra) of the surface. It is preferable that the surface roughness is 1 mm ² randomly taken out from an area of 100 cm ² , and the average surface roughness (Ra) is 0.01 to 0.4 μm per 1 mm ² area of the extracted surface. More preferably, it is 0.03-0.3 micrometer, More preferably, it is 0.05-0.25 micrometer, Most preferably, it is 0.07-0.2 micrometer.
A well-known method is used as a method of forming surface irregularities. For example, by using fine particles in the low refractive index layer, thereby forming irregularities on the film surface (for example, JP-A-2000-271878, etc.), the irregular shape is physically transferred to the surface of the low refractive index layer ( Embossing method etc.) (for example, JP-A-11-268800).

<Protective film for polarizing plate>
When the antireflection film of the present invention is used as a protective film for a polarizing film (protective film for polarizing plate), the surface of the transparent support opposite to the side having the high refractive index layer, that is, the surface to be bonded to the polarizing film It is preferable that the contact angle with respect to water be 40 ° or less to ensure sufficient adhesion to the polarizing film.
As the transparent support, it is particularly preferable to use a triacetyl cellulose film.
The following two methods are mentioned as a method of producing the protective film for polarizing plates in this invention.
(1) A method of coating each of the above layers (for example, a hard coat layer, a high refractive index layer, a low refractive index layer, etc.) on one surface of a saponified transparent support.
(2) A method in which the above layers (for example, a hard coat layer, a high refractive index layer, a low refractive index layer, etc.) are coated on one surface of the transparent support, and then the side to be bonded to the polarizing film is saponified.

  Furthermore, a saponification treatment solution can be applied to the surface of the transparent support on the side to be bonded to the polarizing film of the antireflection film, and the side to be bonded to the polarizing film can be saponified.

  Protective films for polarizing plates have optical performance (antireflection performance, antiglare performance, etc.), physical performance (such as scratch resistance), chemical resistance, antifouling performance (contamination resistance, etc.), weather resistance (moisture and heat resistance, light resistance) In terms of properties, it is preferable to satisfy the performance described in the antireflection film of the present invention.

<Surface treatment>
The hydrophilic treatment of the surface of the transparent support can be performed by a known method. Examples thereof include a method of modifying the surface of the transparent support film by corona discharge treatment, glow discharge treatment, ultraviolet irradiation treatment, flame treatment, ozone treatment, acid treatment, alkali treatment and the like. Details of these are described in detail on pages 30 to 32 of the aforementioned public technical number 2001-1745. Of these, alkali saponification treatment is particularly preferable, and is extremely effective as a surface treatment when a cellulose acetate film is used as a transparent support.
It is preferable to saponify the transparent support or the antireflection film in an alkali solution by immersing it for an appropriate time or by applying an alkali solution. Examples of the alkaline solution and treatment include the contents described in JP-A No. 2002-82226 and WO 02/46809 pamphlet. The saponification treatment is preferably carried out so that the contact angle with water on the film surface is 45 ° or less.
The protective film for polarizing plate is used by adhering the hydrophilic surface of the transparent support to the polarizing film.

<Polarizing plate>
The preferable polarizing plate of this invention has the antireflection film of this invention in at least one of the protective film (protective film for polarizing plates) of a polarizing film. As described above, the polarizing plate protective film has a water contact angle of 40 ° or less on the surface of the transparent support opposite to the side having the high refractive index layer, that is, the surface to be bonded to the polarizing film. It is preferable.
By using the antireflection film of the present invention as a protective film for a polarizing plate, a polarizing plate having an antireflection function can be produced, and the cost can be greatly reduced and the display device can be thinned.
Further, by preparing a polarizing plate using the antireflection film of the present invention as one of the protective films for polarizing plates and an optical compensation film having optical anisotropy described later as the other protective film of the polarizing film, Thus, a polarizing plate capable of improving the contrast in the bright room of the liquid crystal display device and greatly widening the vertical and horizontal viewing angles can be produced.

<Optical compensation film>
The optical compensation film (retardation film) can improve the viewing angle characteristics of the liquid crystal display screen.
A known film can be used as the optical compensation film. However, in terms of widening the viewing angle, an optical compensation layer made of a compound having a discotic structural unit described in JP-A-2001-100042 is provided. An optical compensation film characterized in that the angle formed by the discotic compound and the support is changed in the depth direction of the layer is preferable.
The angle preferably increases as the distance from the support surface side of the optically anisotropic layer increases.

When the optical compensation film is used as a protective film for the polarizing film, the surface on the side to be bonded to the polarizing film is preferably saponified, and is preferably performed according to the saponifying process.
Also, an aspect in which the optically anisotropic layer further contains a cellulose ester, an aspect in which an alignment layer is formed between the optically anisotropic layer and the transparent support, and an optical compensation film having the optically anisotropic layer It is also preferable that the transparent support has an optically negative uniaxial property and has an optical axis in the normal direction of the surface of the transparent support.

<Image display device>
The antireflection film 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). The antireflection film adheres the transparent support side of the antireflection film to the image display surface of the image display device.

The antireflection film and polarizing plate used in the present invention are twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), optically compensated bend cell ( It can be preferably used for a transmissive, reflective, or transflective liquid crystal display device in a mode such as OCB).
When used in a transmissive or transflective liquid crystal display device, it is used in combination with a commercially available brightness enhancement film (a polarized light separation film having a polarization selective layer, such as D-BEF manufactured by Sumitomo 3M Co., Ltd.). Thus, a display device with higher visibility can be obtained.
Further, when combined with a λ / 4 plate, it can be used to reduce reflected light from the surface and inside as a polarizing plate for reflective liquid crystal or a surface protective plate for organic EL display.

  Although the specific Example of this invention is described below, this invention is not limited to these.

<Example 1> and <Comparative example>
[Preparation of oxide fine particle dispersion (PL-1)]
Titanium dioxide fine particles surface-treated with aluminum oxide and stearic acid (TTO-51 (C): titanium oxide content 79-85%: manufactured by Ishihara Sangyo Co., Ltd.) (P-1) 100 g, dispersant having the following structure (D- 1) 22 g and 285 g of cyclohexanone were dispersed together with zirconia beads having a particle diameter of 0.1 mm (YTZ ball, manufactured by Nikkato Co., Ltd.) using a dynomill. The dispersion temperature was 35 to 40 ° C. for 8 hours. The beads were separated with a 200 mesh nylon cloth to prepare an oxide fine particle dispersion (PL-1).

The dispersion particle diameter of the obtained dispersion was a particle having an average particle diameter of 75 nm with good monodispersity as measured by a scanning electron microscope.
Moreover, as a result of measuring the particle size distribution of the dispersion (Laser analysis / scattered particle size distribution measuring apparatus LA-920, manufactured by HORIBA, Ltd.), the particle size of 300 nm or more was 0%.

  Further, when the properties of the obtained dispersion were allowed to stand for one month were examined, no precipitation was observed in the dispersion, the particle size of the dispersed particles was the same as before the aging, and the particles of 300 nm or more were 0 %Met.

[Preparation of hard coat layer coating solution (HC-1)]
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 content 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. The solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for a hard coat layer.

[Preparation of Medium Refractive Index Layer Coating Solution (ML-1)]
A mixed solvent of 452.4 g of methyl ethyl ketone and 1753.7 g of cyclohexanone was added to 88.9 g of the oxide fine particle dispersion (PL-1) with stirring. Next, a mixed solvent of DPHA, 58.4 g, Irgacure 907, 3.1 g, photosensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.) 1.1 g, methyl ethyl ketone 30.0 g, and cyclohexanone 116.1 g are added. And stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for the medium refractive index layer.

[Preparation of coating liquid for high refractive index layer (HL-1)]
A mixed solvent of 198.1 g of methyl ethyl ketone and 792.4 g of cyclohexanone was added to 400 g of the above oxide fine particle dispersion (PL-1) with stirring. Next, a mixed solution of DPHA, 37.5 g, Irgacure 907, 2.0 g, photosensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.) 0.5 g, methyl ethyl ketone 18.7 g, and cyclohexanone 74.6 g is added. Then, ultrasonic dispersion was performed for 10 minutes. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

[Preparation of coating solution for low refractive index layer]
A heat-crosslinkable fluoropolymer having a refractive index of 1.42 (JN7228, solid content concentration of 6% by mass, manufactured by JSR Corporation) is substituted with a solvent, and methyl isobutyl ketone having a solid content concentration of 10% by mass of the heat-crosslinkable fluoropolymer. A solution was obtained. In addition to 56.0 g of the above heat-crosslinkable fluoropolymer solution, 8.0 g of methyl ethyl ketone dispersion (MEK-ST, solid content concentration 30% by mass, manufactured by Nissan Chemical Co., Ltd.) of silica fine particles, 1.75 g of the following silane compound, and 73.0 g of methyl isobutyl ketone and 33.0 g of cyclohexanone were added and stirred. The solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for a low refractive index layer.

[Adjustment of silane compound]
A reactor equipped with a stirrer and a reflux condenser, 161 g of 3-acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), 123 g of oxalic acid, and 415 g of ethanol were added and mixed. After making it react for time, it cooled to room temperature and obtained the transparent silane compound as a curable composition.

[Preparation of antireflection film]
With a corona static eliminator, the surface of the coated side of a 80 μm thick triacetyl cellulose film (TD80UF, manufactured by Fuji Photo Film Co., Ltd.) is subjected to static elimination treatment, and then a hard coat layer coating solution (HC-1) is applied to the gravure coater. Applied. 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. The} coating layer was cured by irradiating with an irradiation amount of 500 mJ / cm ² to form a 5 μm thick hard coat layer. On the hard coat layer, a medium refractive index layer coating solution (ML-1) was applied using a gravure coater. After drying at 100 ° C., an illuminance of 550 mW / cm using an air-cooled metal halide lamp (made by Eye Graphics Co., Ltd.) of 240 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 volume% or less. ^2. An ultraviolet ray with an irradiation amount of 550 mJ / cm ² was irradiated to cure the coating layer to form a medium refractive index layer (refractive index 1.63, film thickness 70 nm).

On the middle refractive index layer, a coating solution for high refractive index layer (HL-1) was applied using a gravure coater. After drying at 100 ° C., using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0 vol% or less, an illuminance of 550 mW / A high refractive index layer (refractive index: 1.90, film thickness: 100 nm) was formed by irradiating ultraviolet rays with a cm ² and an irradiation amount of 550 mJ / cm ² and heating at 120 ° C. for 10 minutes. In this way, an antireflection film was produced.

On the high refractive index layer, the low refractive index layer coating solution was applied using a gravure coater. After drying at 80 ° C., using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less, the illuminance is 550 mW / cm ^2, an irradiation dose of 600 mJ / cm ^2, and heated at 120 ° C. 10 minutes to form a low refractive index layer (refractive index 1.43, film thickness 86 nm). In this way, an antireflection film was produced.

  In the above, the coating and drying steps are performed in an air atmosphere with an air cleanliness of 30 particles / (cubic meter) or less as particles of 0.5 μm or more, and the high cleanliness described in JP-A-10-309553 is just before the coating. The coating was performed while dust was removed by blowing air at a high speed to separate the deposits from the film surface and sucking them with a suction port close to the film. The charged voltage of the base before dust removal was 200 V or less. Said application | coating was performed in each process of sending-out-dust removal-application-dry- (UV or heat) hardening-winding up for every layer.

[Comparative example]
In the oxide dispersion (PL-1) of Example 1, the dispersion state (bead amount, bead diameter, dispersion time) is changed to change the degree of dispersion of the oxide dispersed particles so that the surface state shown in Table 1 below is obtained. A sample having a high refractive index layer was prepared while adjusting the thickness to. Otherwise, an antireflection film was produced in the same manner as in Example 1.

[Evaluation of high refractive index layer film]
Using the film provided up to the high refractive index layer, the following items were evaluated.
(Evaluation of surface shape)
Based on JISB0601-1994, the shape of the surface of the high refractive index layer film is arithmetic average roughness (Ra), ten-point average roughness (Rz), maximum height (Ry), and average interval of surface irregularities. (Sm) was evaluated by an atomic force microscope (AFM). However, Ra, Rz, and Ry were measured at 4 μm, and Sm was measured at 20 μm. The uniformity of the surface irregularities was calculated by the ratio (Ra / Rz). The results are shown in Table 1.
(Evaluation of haze)
The haze of the high refractive index layer film was evaluated using a haze meter (NHD-1001DP, manufactured by Nippon Denshoku Industries Co., Ltd.). The results are shown in Table 2.

(Evaluation of pencil hardness)
The high refractive index layer film was conditioned for 2 hours under the conditions of a temperature of 25 ° C. and a relative humidity of 60%, and then visually evaluated using a 3H test pencil specified by JIS S6006 under a load of 1 kg with the following contents. . The results are shown in Table 2.
No scratch is observed in the evaluation of n = 5: ○
One or two scratches in the evaluation of n = 5: Δ
In evaluation of n = 5, 3 or more scratches: ×

<Evaluation of antireflection film>
About each produced antireflection film, evaluation as described above and evaluation of the following items were performed. The obtained results are shown in Table 2.
In addition, (evaluation of haze) and (evaluation of pencil hardness) were performed in the same manner as the above [evaluation of high refractive index layer film].

(Evaluation of reflectance)
Using a spectrophotometer (V-550, ARV-474, manufactured by JASCO Corporation), the spectral reflectance at an incident angle of 5 ° was measured in the wavelength region of 380 to 780 nm. The average reflectance in the wavelength range of 450 to 650 nm was determined.
(Evaluation of bright spot foreign matter)
The back surface of the film after all layers were applied was black-coated with magic ink or the like, and the number of bright spot defects on the coating film was visually determined. The size of the bright spot defect that can be visually observed is 50 μm or more. Bright spot defects were counted in number per square meter.

(Evaluation of wear resistance)
Each antireflection film was conditioned at a temperature of 25 ° C. and a relative humidity of 60% for 2 hours, and then cut into a size of 10 cm × 10 cm. Using this as a test sample, a Taber abrasion test was conducted according to JISK-6902. The amount of wear after 500 rotations under a 1 kg load was measured. Before the test, the mass of the test sample was measured to the mg unit, the mass of the test sample after the test was measured, and the wear amount of the coating was calculated.

(Evaluation of adhesion)
Each antireflection film was conditioned for 2 hours at a temperature of 25 ° C. and a relative humidity of 60%. On the surface of each antireflection film on the side having the high refractive index layer, a cutter knife is used to cut 11 vertical and 11 horizontal cuts in a grid pattern to make a total of 100 square squares. Nitto Denko Corporation The adhesion test using a polyester adhesive tape (NO. 31B) was repeated three times at the same place. The presence or absence of peeling was visually observed, and the following four-stage evaluation was performed.
A: No peeling at 100 mm was observed. ○: No peeling was observed at 100 mm within 2 mm. Δ: 10-100 mm was observed at 100 mm. Thing that has been peeled off at 100 mm exceeds 10 mm

(Evaluation of abrasion resistance)
In the antireflection film before and after the exposure, a load of 500 g / cm ² was applied to # 0000 still wool, and the state of scratches after 50 reciprocations was observed and evaluated in the following three stages.
A: No scratch at all, B: Slightly scratched but difficult to see, C: Scratched significantly

In Example 1 of the present invention, haze, reflectance, and bright spot foreign matter were all good. In addition, the abrasion resistance was 40 mg, which was in a practically unproblematic range, and was excellent in pencil hardness, adhesion, and abrasion resistance performance. On the other hand, each of the comparative examples of the surface irregularity shape deviating from the preferred range of the present invention has a wear amount of 60 mg or more in the wear resistance test, and the adhesion and rubbing resistance are also reduced, so that it is practically used. Became a problem level.
From the above results, only the product of the present invention showed excellent performance.

Furthermore, the contact angle of the antireflection film of Example 1 of the present invention with water on the surface was 101 degrees, and the dynamic friction coefficient was 0.08. These measurements were performed as follows.
(Evaluation of contact angle)
The antireflection film was conditioned for 2 hours at a temperature of 25 ° C. and a relative humidity of 60%. The contact angle with respect to water of the surface having the low refractive index layer of the antireflection film was evaluated.
(Evaluation of dynamic friction coefficient)
The coefficient of dynamic friction was evaluated as an index of the slipperiness of the surface of the antireflection film having the low refractive index layer. The dynamic friction coefficient was adjusted for 2 hours under the conditions of a temperature of 25 ° C. and a relative humidity of 60% using a dynamic friction coefficient measuring machine (HEIDON-14) with a stainless hard ball having a diameter of 5 mm at a load of 100 g and a speed of 60 cm / min. It was measured.

<Example 2>
[Preparation of oxide fine particle dispersion (PL-2)]
Preparation of titanium dioxide fine particles (P-2): In accordance with JP-A-5-330825, except that iron (Fe) is changed to cobalt (III) chloride, titanium dioxide particles are contained in the titanium dioxide particles. Cobalt-containing titanium dioxide fine particles doped with cobalt were prepared.
The amount of cobalt doped was 98.5 / 1.5 in terms of Ti / Co (mass ratio).
The produced titanium dioxide fine particles had a rutile crystal structure, and the average primary particle size was 40 nm, the specific surface area was 38 nm, and the specific surface area was 44 m ² / g.

  Oxide fine particle dispersion: 100 g of the above oxide fine particles (P-2), 20 g of a polymer dispersant having the following structure, and 360 g of cyclohexanone were added and dispersed by dynomill together with zirconia beads having a particle diameter of 0.1 mm. The dispersion temperature was 35 to 40 ° C. for 5 hours. An oxide fine particle dispersion (PL-2) having an average diameter of 55 nm with a particle diameter of 300 nm or more being 0% was prepared.

[Preparation of oxide fine particle dispersion (PL-3)]
Preparation of titanium dioxide fine particles (PL-3): Zirconyl nitrate (ZrO (NO ₃ ) was added to titanium dioxide particles in the same manner except that iron (Fe) was changed to zirconium based on JP-A-5-330825. ₂ ) Zirconium-containing titanium dioxide fine particles doped with ₂ ) were prepared. The doped amount of zirconium was 97.5 / 2.5 in terms of Ti / Zr (mass ratio).
The produced titanium dioxide fine particles had a rutile-type crystal structure, the average particle size of primary particles was 40 nm, and the specific surface area was 39 m ² / g.
Oxide fine particle dispersion: To 100 g of the above oxide fine particles (P-3), 18 g of the following dispersant and 303 g of cyclohexanone were added and dispersed by dynomill using zirconia beads having a particle diameter of 0.1 mm. The dispersion temperature was 40 to 45 ° C. and the dispersion time was 6 hours to prepare an oxide fine particle dispersion (PL-3). The average diameter of the dispersed particles of the obtained dispersion was 55 nm, and the particle size of 300 nm or more was 0%.

[Preparation of oxide fine particle dispersion (PL-4)]
Preparation of titanium dioxide fine particles (P-4): In the same manner except that iron (Fe) is changed to cobalt (III) chloride and aluminum chloride based on JP-A-5-330825. Cobalt and aluminum-containing titanium dioxide fine particles doped with cobalt and aluminum were prepared. The doping amount of cobalt and aluminum was Ti / Co / Al (mass ratio), and was 97.5 / 1.25 / 1.25.
The produced titanium dioxide fine particles had a rutile-type crystal structure, the average particle size of primary particles was 40 nm, and the specific surface area was 39 m ² / g.
Oxide fine particle dispersion: To 100 g of the above oxide fine particles (P-4), 22 g of the following dispersant and 366 g of cyclohexanone were added and dispersed by dynomill using zirconia beads having a particle diameter of 0.1 mm. The dispersion temperature was 40 to 45 ° C. and the dispersion time was 6 hours to prepare an oxide fine particle dispersion (PL-4). The average diameter of the dispersed particles of the obtained dispersion was 55 nm, and the particle size of 300 nm or more was 0%.

[Preparation of Oxide Fine Particle Dispersion (PL-5)]
In Example 7 of JP-T-2001-525784, a titanium-tantalum composite oxide sol was produced using a tantalum oxide (Ta ₂ O ₅ ) hydrated gel instead of the zirconium compound. In the example of JP-A-5-330825, the above complex oxide sol is used instead of the titanium oxide sol, and the ferrous sulfate is replaced with cobalt nitrate, and cobalt ion-doped (doping amount 4 mass%) Ti and Ta are used. A composite oxide (P-5) [Ti / Ti + Ta = 0.8 molar ratio] was produced. A mixture of 92 g of cobalt oxide-doped composite oxide fine particles (P-5), 31 g of a silyl compound having the following structure and 337 g of cyclohexano was finely dispersed in a sand mill (1/4 G sand mill) for 6 hours. The media used was 1400 g of 0.2 mmφ zirconia beads. 1N hydrochloric acid 0.1g was added here, and it heated up at 80 degreeC by nitrogen atmosphere, and also stirred for 4 hours. The obtained surface-treated doped composite oxide fine particles had a particle size of 60 nm, and the particle size of 300 nm or more was 0%.

[Preparation of Oxide Fine Particle Dispersion (PL-6)]
In Example 9 of JP-T-2001-525784, a titanium / bismuth / zirconium composite oxide produced in the same manner except that bismuth nitrate was used instead of gadolinium nitrate [Bi / Bi + Ti + Zr = 0.08 molar ratio, Zr / Bi + Ti + Zr = 0.05 molar ratio] (P-6) 25 g of the following dispersant and 375 g of cyclohexanone were added and dispersed by dynomill using zirconia beads having a particle diameter of 0.1 mm. The dispersion temperature was 40 to 45 ° C. and the dispersion time was 6 hours to prepare a composite oxide fine particle dispersion. The average diameter of the dispersed particles of the obtained dispersion was 75 nm, and the particle size of 300 nm or more was 0%.

<Example 2-1>
[Preparation of hard coat layer coating solution (HC-2)]
After dissolving 809 g of a methyl ethyl ketone 53.2 mass% solution of 1296 g of trimethylolpropane triacrylate and polyglycidyl methacrylate (mass average molecular weight: 1.5 × 10 ⁴ ) in a mixed solution of 943 g of methyl ethyl ketone and 880 g of cyclohexanone, Irgacure was stirred. 184, 48.1 g, and 24 g of di (t-butylphenyl) iodonium hexafluorophosphate were added and stirred for 10 minutes. The mixture was filtered through a polypropylene filter having a pore size of 0.1 μm to prepare a hard coat layer coating solution (HC-2).

[Preparation of Medium Refractive Index Layer Coating Solution (ML-2)]
To 88.9 g of the above oxide fine particle dispersion (PL-2), polyfunctional acrylate DPHA, 58.4 g, Irgacure 907, 3.1 g, Kayacure DETX, 1.1 g, methyl ethyl ketone 482.4 g, and cyclohexanone 1869. 8 g was added and stirred. After ultrasonic dispersion for 10 minutes, the solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution (ML-2) for a medium refractive index layer.

[Preparation of coating solution for high refractive index layer (HL-2-1)]
A mixed solvent of 204.4 g of methyl ethyl ketone and 817.6 g of cyclohexanone was added to 500 g of the oxide fine particle dispersion (PL-2) with stirring. Next, a mixed solution of DPHA, 37.5 g, Irgacure 907, 2.5 g, photosensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.) 0.8 g, methyl ethyl ketone 19 g, and cyclohexanone 76.2 g was added. After stirring, ultrasonic dispersion was performed for 10 minutes. The mixture was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for high refractive index layer (HL-2-1).

[Preparation of antireflection film]
On the triacetyl cellulose film (TD80UF), a hard coat layer coating solution (HC-2) was applied using a gravure coater. After drying at 100 ° C., it was dried at 120 ° C. Next, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0 vol% or less, an illuminance of 400 mW / cm ² and an irradiation amount of 500 mJ The coating layer was cured by irradiating UV light of / cm ² to form a hard coat layer having a thickness of 8 μm.

On the hard coat layer, an intermediate refractive index layer coating solution (ML-2) 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 1.67, film thickness 70 nm).

On the middle refractive index layer, a coating solution for high refractive index layer (HL-2-1) 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 high refractive index layer (refractive index 1.95, film thickness 105 nm).

On the high refractive index layer, the low refractive index layer (refractive index 1.44, film thickness 82 nm) was formed according to the composition for low refractive index layer described in Example 1 of JP-A-2000-241603 and the formation method. ) Was formed. In this way, an antireflection film was produced.
In the above, the coating and drying steps were performed under the same conditions as in Example 1.

<Example 2-2 to Example 2-5>
In Example 2-1, instead of the oxide fine particle dispersion (PL-2), 100 g (as solid content) of each oxide fine particle dispersion (PL-3 to PL-6) having the contents shown in Table 3 below was used. An antireflection film was produced in the same manner as in Example 2-1, except that the surface state of the high refractive index layer was adjusted to the surface state shown in Table 3 below.

[Evaluation of high refractive index layer film and antireflection film]
Each sample was evaluated in the same manner as in Example 1 for each sample. As a result, both the high refractive index layer film and the antireflection film exhibited good performance equivalent to or better than that of Example 1.
Further, the following weather resistance test was conducted.
(Conditions for weather resistance test)
Using a sunshine weather meter (S-80, manufactured by Suga Test Instruments Co., Ltd.), a weather resistance test was performed under the conditions of a sunshine carbon arc lamp, a relative humidity of 60%, and 100 hours.
Each sample after the test was evaluated in the same manner as the evaluation method of Example 1. The results are shown in Table 4. By replacing the oxide fine particle dispersion of the coating solution for the high refractive index layer, an improvement in wear resistance was observed.

<Example 3>
[Preparation of hard coat layer coating solution (HC-3)]
Multifunctional acrylate monomer DPHA, 125 g, urethane acrylate oligomer UV-6300B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 125 g, Irgacure 907, 7.5 g and Kayacure DETX, 5.0 g, methyl ethyl ketone 192.5 g and cyclohexanone 128 Dissolved in 3 g of mixed solution. After the mixture was stirred, it was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a hard coat layer coating solution (HC-3).

[Preparation of oxide fine particle dispersion (PL-7)]
Titanium / zirconium composite oxide [Ti / Ti + Zr = 0.80 mass ratio (as oxide)] fine particles produced in the same manner as in Example 7 of JP-T-2001-525784 are subjected to Co ions by the above-described ion implantation method. Is added to 218 g of fine particles (P-7) doped with 3% by mass of a dispersant, 38.6 g of a dispersant having the following structure, 0.5 g of a polymerization inhibitor t-butylhydroquinone, and 702 g of methyl isobutyl ketone, and dispersed by dynomill. A high refractive index composite oxide fine particle dispersion (PL-7) having an average diameter of 65 nm was prepared. The surface-treated oxide fine particles obtained had a particle size of 50 nm. Further, the particle size of 300 nm or more was 0%.

[Preparation of coating solution for high refractive index layer (HL-3)]
65 g of methyl cellosolve, 20 g of tetraethoxysilane, 26 g of methyltrimethoxysilane and 54 g of 3-acryloyloxypropylmethyldimethoxysilane were added, the liquid temperature was kept at 5 to 10 ° C., and 36.8 g of 0.01 N hydrochloric acid was added while stirring. It was dripped in 3 hours. After completion of dropping, the mixture was stirred for 0.5 hours to obtain a partial hydrolyzate of the silyl compound. Next, 374.5 g of the oxide fine particle dispersion (PL-7) (concentration: 26.7% by mass), 11.8 g of pentaerythritol tetraacrylate, 2.2 g of zirconium acetylacetonate as a curing agent, and 0.5 g of oxalic acid , Irgacure 907, 0.6 g, and Kayacure-DETX 0.4 g were added to 57.1 g of the partial hydrolyzate of the above silyl compound, sufficiently stirred, and then filtered to obtain a coating solution for high refractive index layer (HL- 3) was adjusted.

[Preparation of coating solution for antifouling layer]
Isopropyl alcohol was added to a thermally crosslinkable fluorine-containing polymer (JN-7214, manufactured by JSR Corporation) to prepare a 0.6% by mass crude dispersion. The coarse dispersion was finely dispersed with ultrasonic waves to prepare an antifouling layer coating solution.

[Preparation of antireflection film]
A cellulose acylate film having a thickness of 80 μm was produced by the method described in Example 1 of JP-A-2001-151936. A hard coat layer and a medium refractive index layer described in Example 1 were formed on this transparent support using (HC-3) and (ML-1). On the middle refractive index layer, a coating solution for high refractive index layer (HL-3) 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. Irradiation with an irradiation amount of 600 mJ / cm ² , followed by heating at a temperature of 100 ° C. for 20 minutes to cure the coating layer to form a high refractive index layer (refractive index 1.94, film thickness 100 nm). The shape of the surface of the obtained high refractive index layer was as follows.

    Ra: 0.012 μm, Rz: 0.06 μm, Rz / Ra ratio: 0.20, Ry: 0.045, Sm: 0.25 μm

On the high refractive index layer, a 88 nm-thick silica vapor deposition film (refractive index 1.46) was formed by vacuum vapor deposition using an electron beam type vacuum vapor deposition apparatus. On the silica vapor deposition film, the antifouling layer coating solution was applied using a # 3 wire bar and dried at 120 ° C. for 1 hour to prepare an antireflection film.
In addition, application | coating and drying were performed on the conditions similar to Example 1 description.
The obtained antireflection film was evaluated in the same manner as in Example 2-1, and each performance showed good results equivalent to those in Example 2-1.

<Example 4>
[Preparation of protective film for polarizing plate]
In each of the antireflection films prepared in Example 1, Examples 2-1 to 2-5, and Example 3, the surface of the transparent support opposite to the side having the high refractive index layer of the present invention is water. A saponification solution in which an alkali solution composed of 57 parts by mass of potassium oxide, 120 parts by mass of propylene glycol, 535 parts by mass of isopropyl alcohol, and 288 parts by mass of water was kept at 40 ° C. was applied for saponification treatment.
The alkaline solution on the surface of the saponified transparent support was thoroughly washed with water and then sufficiently dried at 100 ° C. Thus, the protective film for polarizing plates was produced.

[Preparation of polarizing plate]
A polyvinyl alcohol film having a thickness of 75 μm (manufactured by Kuraray Co., Ltd.) was immersed in an aqueous solution consisting of 1000 g of water, 7 g of iodine and 105 g of potassium iodide to adsorb iodine. Subsequently, this film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by mass boric acid aqueous solution, and then dried in a tension state to produce a polarizing film.
A saponified triacetyl cellulose surface of the antireflection film of the present invention (protective film for polarizing plate) was bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive. Further, a cellulose acylate film: TD80UF saponified in the same manner as described above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive.

[Evaluation of image display device]
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type liquid crystal display device equipped with the polarizing plate of the present invention thus produced has excellent antireflection performance and is extremely Visibility was excellent.

<Example 5>
[Preparation of polarizing plate]
The disc surface of the discotic structural unit is inclined with respect to the transparent support surface, and the angle formed by the disc surface of the discotic structural unit and the transparent support surface varies in the depth direction of the optically anisotropic layer. In the optical compensation film having the optically anisotropic layer (WV A 12B, manufactured by Fuji Photo Film Co., Ltd.), the surface opposite to the side having the optically anisotropic layer is saponified under the same conditions as in Example 4. Processed.
The polarizing film produced in Example 4 was saponified with the antireflection film (protective film for polarizing plate) produced in Example 4 on one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive. The triacetyl cellulose surface was bonded. Further, the triacetyl cellulose surface of the saponified optical compensation film was bonded to the other surface of the polarizing film using the same polyvinyl alcohol adhesive.

[Evaluation of image display device]
The TN, STN, IPS, VA, OCB mode transmissive, reflective, or transflective liquid crystal display device equipped with the polarizing plate of the present invention thus manufactured does not use an optical compensation film. Compared with a liquid crystal display device equipped with a polarizing plate, the contrast in a bright room was excellent, the viewing angles of the top, bottom, left and right were very wide, and the antireflection performance was excellent, and the visibility and display quality were extremely excellent.

Claims (13)

  In a multilayer antireflection film having at least two refractive index layers of a high refractive index layer and a low refractive index layer in this order on a transparent support, a surface based on JIS B0601-1994 is provided on the surface of the high refractive index layer. The arithmetic average roughness (Ra) of the unevenness is 0.001 to 0.03 μm, the ten-point average roughness (Rz) is 0.001 to 0.06 μm, and the maximum height (Ry) is 0.09 μm. An antireflection film, wherein the following uneven form is formed.   The ratio (Ra / Rz) between the arithmetic average roughness (Ra) and the ten-point average roughness (Rz) of the surface irregularities is 0.1 or more, and the average interval of the surface irregularities based on JIS B0601-1994 (Sm The antireflection film according to claim 1, which is 1 μm or less.   The high refractive index layer comprises a cured film having a refractive index of 1.55 to 2.50, and the antireflection film has an abrasion amount of 50 mg or less in a Taber abrasion test based on JISK-6902. 3. The antireflection film as described in 1 or 2.   The high refractive index layer contains inorganic fine particles mainly composed of titanium dioxide containing at least one metal atom selected from cobalt, aluminum, and zirconium, and the layer has a refractive index of 1.55 to 2.50. The antireflection film according to claim 1, wherein the antireflection film is a cured film.   The antireflection film according to claim 4, wherein the metal atom contained in the inorganic fine particles mainly containing titanium dioxide is cobalt.   The high refractive index layer is a haze after 150 hours treatment based on accelerated weather resistance JISK5600-7-7: 1999, and the amount of wear in the Taber abrasion test based on JISK-6902 is a change from the layer before the weather resistance test. The antireflection film according to claim 4, wherein the antireflection film has a rate of 10% or less.   The above-mentioned antireflection film is characterized in that it is 20 or less per square meter in the number of luminance defects having a diameter of 50 μm or more, which are optical foreign matters generated after 150 hours of treatment based on accelerated weather resistance JISK5600-7-7: 1999. The antireflection film according to any one of claims 4 to 6.   The said high refractive index layer contains the at least 1 sort (s) of matrix chosen from the organic-binder, an organometallic compound, and the partial hydrolyzate of an organometallic compound, The any one of Claims 1-7 characterized by the above-mentioned. Antireflection layer.   On the transparent support, the cured film according to any one of claims 1 to 8 is laminated in two layers having different refractive indexes, and a low refractive index layer having a refractive index of less than 1.55 is further laminated to form a three-layer structure. An antireflective film characterized by being formed.   The antireflection film according to claim 1, wherein a hard coat layer is provided between the transparent support and the high refractive index layer.   A polarizing plate comprising the antireflection film according to claim 1 as at least one of a protective film for a polarizing film.   The antireflection film according to claim 1 is used for one of the protective films of the polarizing film, and an optical compensation film having optical anisotropy is used for the other of the protective films of the polarizing film. Polarizer.   An image display device comprising the antireflection film according to claim 1 or the polarizing plate according to claim 11 or 12 arranged on an image display surface.