JP2006091859A - Anti-reflection film, and polarizing plate and image display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anti-reflection film having excellent anti-reflection properties, a good white color and an excellent viewability, a method for manufacturing this kind of anti-reflection film, a polarizing plate with anti-reflection power using this kind of anti-reflection film as a protective film of one side of a polarizing film, and an image display device having this kind of anti-reflection film and/or the polarizing plate with anti-reflection power mounted thereon. <P>SOLUTION: The anti-reflection film is constructed by arranging an anti-reflection layer containing at least one or more thin layers having a refractive index different from that of a transparent support on the transparent support with application such that the average value of specular reflectance is kept not greater than a specific value, wherein the amount I<SB>50</SB>of light scattered in a specified direction and the total amount I of scattering light of incident light, out of scattering light scattered from the surface of the anti-reflection film satisfy a specified relation with respect to the light incident on the surface of the anti-reflection film from the specified direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an antireflection film, a polarizing plate using it as at least one side of a protective film, and an image display device using the same.

  Antireflection films are used in various image display devices such as liquid crystal display devices (LCD), plasma display panels (PDP), electroluminescence displays (ELD), and cathode ray tube display devices (CRT) to reflect external light and In order to prevent a decrease in contrast due to reflection, it is arranged on the surface of the display. Therefore, in addition to high antireflection performance, the antireflection film is required to have high transmittance, high physical strength (such as scratch resistance), chemical resistance, and weather resistance (such as moisture and heat resistance).

  Conventionally, an antireflection layer used for an antireflection film has been formed as a single-layer or multilayer thin film. In the case of a single layer, a layer having a lower refractive index than that of the substrate (low refractive index layer) may be formed with an optical thickness of 1/4 of the design wavelength. If further low reflection is required, a layer (high refractive index layer) having a refractive index higher than that of the substrate may be formed between the substrate and the layer having a low refractive index.

  As the multilayer antireflection film, a multilayer film obtained by laminating a transparent thin film of metal oxide has been widely used. The metal oxide transparent thin film has been usually formed by a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method, particularly a vacuum vapor deposition method which is a kind of physical vapor deposition method.

  The multilayer antireflection film is also formed by a wet coating method. There is a strong demand for the formation of an antireflection film by a wet coating method, which is suitable for mass production and cost reduction, as compared with the vacuum deposition method.

When producing an antireflection film by a wet coating method, a film-forming composition having a specific refractive index is adjusted by dissolving or dispersing it in a solvent. It is formed by curing accordingly.
In order to form a low refractive index layer, many examples of using a fluorine-containing material or an inorganic material as a substance having a low refractive index have been disclosed.
In order to form a high refractive index layer by a wet coating method, it has been proposed to finely disperse inorganic fine particles having a high refractive index and introduce them into a film (see, for example, Patent Documents 4 to 7). .

  However, when these antireflection films by the wet coating method are applied to an image display device, there is a problem that when the display is viewed from an oblique direction, the black display appears whiteish black or gray. This phenomenon is expressed as “black sinking is bad”, “black floating is bad”, “black is not tight”, “black is whitish”, or “white is bad”. On the other hand, if black appears to be the original black, “Black subsidence is good”, “Black float is good”, “No black float”, “Black tightness is good”, “Black appears black” Or “white taste is good”. This leads to a deterioration in contrast, and further has a problem of degrading the high-quality display and display quality of the display.

  On the other hand, technologies for suppressing whiteness in antiglare films and antiglare antireflection films that prevent reflection due to uneven shapes have been disclosed (for example, Patent Documents 1 to 3).

In recent years, there has been a very high demand for large-size, high-definition, high-quality images in image display devices. The whiteness of the antireflection film used for the outermost layer of the image display device and the color of the reflected color are neutral. There is a strong desire to be.
JP 2001-281402 A JP 2001-281403 A JP 2003-222713 A JP 2001-188104 A JP 2003-262702 A JP 2002-286907 A JP 2003-292831 A

An object of the present invention is to provide an antireflection film having a high antireflection property, good whiteness and excellent visibility when used in an image display device.
Another object is to provide a method for producing an antireflection film having excellent characteristics as described above.
Still another object of the present invention is to provide a polarizing plate with antireflection ability that has high antireflection properties, good whiteness and excellent visibility.
Still another object of the present invention is to provide an image display device which has a high antireflection property, an antireflection treatment with good whiteness and excellent visibility.

As a result of research, the present inventors have determined that “whiteness” of an antireflection film is a part of scattered light scattered on the antireflection film surface of incident light from a specific direction to the antireflection film. It was found that the amount of scattered light in this direction and the total amount of all scattered light of incident light were eliminated by satisfying a specific relationship, and “whiteness was improved”.
As a result of conducting research, the present inventors have found that the cause of “poor whiteness” is an organic material, particularly a fluorine-containing material, used for forming a low refractive index layer used on the outermost surface of the antireflection film. When an inorganic material is blended, the inorganic material causes unnecessary agglomeration, and this agglomeration causes fine irregularities on the surface of the film, resulting in excessive scattering of light on the surface of the antireflection film. It is considered that it may cause scattered light and cause “bad whiteness”, and by making the outermost surface of the antireflection film on the antireflection film forming side into a specific shape, “whiteness is further improved. It was found. The surface shape can be made into a specific shape by (a) containing a specific inorganic fine particle in the low refractive index layer, surface-treating the inorganic fine particle, and (b) controlling the drying speed. I found out.
As a result of further research, we found that “whiteness” is also affected by internal scattering due to the high refractive index layer, and by incorporating inorganic fine particles within a specific size range into the high refractive index layer. They found that “whiteness” can be improved.

That is, the present invention achieves the above object by the following configurations.
(1) On the transparent support, an antireflection film comprising at least one thin layer having a refractive index different from that of the transparent support was applied, and the average value of the specular reflectance was suppressed to 3% or less. In the antireflection film, of the scattered light scattered on the antireflection film surface of incident light on the antireflection film surface from a direction inclined by -10 ° from the normal line standing on the surface of the transparent support, An antireflection film, wherein the amount of scattered light I _{50 in} a direction inclined by + 50 ° from the normal and the total amount of scattered light I of the incident light satisfy the relationship of the following formula (1).
Formula (1): -Log (I ₅₀ /I)≧6.6.

(2) The arithmetic average roughness Ra of the antireflection film forming side of the antireflection film is 0.1 to 15 nm, the ten-point average roughness Rz / Ra ratio Rz / Ra is 15 or less, and the uneven profile average The above (having a fine concavo-convex shape having an inclination angle (average inclination angle with respect to the regular reflection surface) of 3 ° or less (
The antireflection film as described in 1).

(3) The antireflection film as described in (1) or (2) above, wherein the antireflection film comprises at least a low refractive index layer having a refractive index lower than that of the transparent support.
(4) The above (3), wherein the low refractive index layer is a cured film formed by coating a composition for forming a low refractive index layer containing at least one selected from thermosetting and radiation curable compositions. The antireflection film as described in 1.
(5) The antireflection film as described in (1) to (4) above, wherein the average value of the specular reflectance is 1% or less.

(6) The antireflection film as described in (3) or (4) above, wherein the refractive index of the low refractive index layer is in the range of 1.20 to 1.49.
(7) Any of the above (3), (4) or (6), wherein the difference between the low refractive index layer and the refractive index of the layer adjacent to the low refractive index layer is 0.16 or more and 1.3 or less The antireflection film as described in 1.
(8) The above (3), (4), (4), wherein the antireflection film has at least one high refractive index layer having a higher refractive index than that of the support between the transparent support and the low refractive index layer. The antireflection film according to any one of 6) and (7).

(9) The antireflective film has a high refractive index layer having a refractive index higher than that of the support, in order from the low refractive index layer side between the transparent support and the low refractive index layer, and the support. The intermediate refractive index layer is formed of a three-layer structure having a middle refractive index layer having an intermediate refractive index of the high refractive index layer. For the design wavelength λ (400 to 680 nm), the middle refractive index layer has the following formula (2): The antireflective film according to any one of (3), (4), and (6) to (8), wherein the refractive index layer satisfies the following formula (3) and the low refractive index layer satisfies the following formula (4): .
Formula (2): (m ₁ λ / 4) × 0.80 <n ₁ d ₁ <(m ₁ λ / 4) × 1.00
Formula (3): (m ₂ λ / 4) × 0.75 <n ₂ d ₂ <(m ₂ λ / 4) × 0.95
Formula (4): (m ₃ λ / 4) × 0.95 <n ₃ d ₃ <(m ₃ λ / 4) × 1.05
Wherein, m ₁ is 1, n ₁ is the refractive index of the medium refractive index layer, and, d ₁ is at a layer thickness of the medium refractive index layer (nm); m ₂ is 2, n ₂ is the refractive index of the high refractive index layer, and d ₂ is the layer thickness (nm) of the high refractive index layer; m ₃ is 1, n ₃ is the refractive index of the low refractive index layer; D ₃ is the thickness (nm) of the low refractive index layer]

(10) The color of the specular reflection light with respect to the incident light with the incident angle of 5 ° of the CIE standard light source D65 in the wavelength region of 380 nm to 780 nm indicates that the a ^* and b ^* values of the CIE1976L ^* a ^* b ^* color space are − The antireflection film according to any one of (1) to (9), wherein 8 ≦ a ^* ≦ 8 and −10 ≦ b ^* ≦ 10.
(11) The antireflection according to any one of (3), (4), or (6) to (10), wherein the low refractive index layer contains 5 to 80% by mass of inorganic fine particles having an average particle diameter of 5 to 100 nm. the film.

(12) The reflection according to (11) above, wherein the inorganic fine particles have been subjected to a treatment for improving dispersibility by a hydrolyzate of organosilane represented by the following general formula (1) and / or a partial condensate thereof. Prevention film.
General formula (1):
(R ¹¹ ) α-Si (Y ¹¹ ) _4- α
(In the formula, R ¹¹ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. Y ¹¹ represents a hydroxyl group or a hydrolyzable group. Α represents an integer of 1 to 3)

(13) The antireflection film according to (12), wherein the dispersibility improving treatment is performed in the presence of at least one of an acid catalyst and the following metal chelate compound.
Metal chelate compound: alcohol represented by general formula R ⁰¹ OH (where R ⁰¹ represents an alkyl group having 1 to 10 carbon atoms) and general formula R ⁰² COCH ₂ COR ⁰³ (where R ⁰² is carbon the number of 1 to 10 alkyl group, R ⁰³ had at least one selected from compounds represented by indicating.) an alkyl group or an alkoxy group having 1 to 10 carbon atoms having 1 to 10 carbon atoms and ligands At least one metal chelate compound having a metal selected from Zr, Ti and Al as a central metal.

(14) The antireflection film as described in any one of (11) to (13), wherein the inorganic fine particles have a hollow structure.
(15) The antireflection film according to any one of (1) to (14), wherein the antireflection film is a cured film formed by coating at a drying rate of 0.10 to 1.5 g / m ² · sec in the drying step. Antireflection film. (16) The above (3), wherein an overcoat layer containing at least one compound selected from a fluorine-containing compound, a silicon-containing compound and a long-chain alkyl group-containing compound having 4 or more carbon atoms is laminated on the low refractive index layer. (4), The antireflection film as described in (6)-(15).

(17) The high refractive index layer contains inorganic fine particles mainly containing titanium dioxide containing at least one element selected from cobalt, aluminum, and zirconium, and the refractive index of the high refractive index layer is The antireflection film according to any one of (8) to (16), which is 1.55 to 2.50.
(18) The average primary particle size of the inorganic fine particles contained in the high refractive index layer is 5 to 100 nm, and any of the above (8) to (17) not containing large particles having a primary particle size of 150 nm or more The antireflection film as described.

(19) The method for producing an antireflection film as described in (1) to (18) above.

(20) A polarizing plate having at least one protective film on the surface of the polarizing film, wherein the protective film is the antireflection film according to any one of (1) to (18) above. Polarizing plate.
(21) The antireflection film according to any one of (1) to (18) is used as one protective film of a polarizing film, and the optical compensation film having optical anisotropy is used as the other protective film of the polarizing film. A polarizing plate characterized by being used as:

(22) An image in which the antireflection film according to any one of (1) to (18) above or the polarizing plate according to (20) or (21) above is disposed on an image display surface. Display device.
(23) The image display device according to (22) above is a TN, STN, VA, IPS, or OCB mode transmissive, reflective, or transflective liquid crystal display device.

  In the antireflection film of the present invention, the scattered light on the outermost surface of the low refractive index layer is controlled, the antireflection property is high, and when this antireflection film is used in an image display device, the whiteness is good and the visibility is high. It is excellent. Furthermore, it is neutral in reflection color, excellent in film strength and durability.

  Moreover, the polarizing plate using the antireflection film of the present invention as a protective film becomes a polarizing plate provided with an antireflection film excellent in optical performance, physical strength, and weather resistance, and can be provided in a large amount at a low cost.

  Furthermore, the image display device of the present invention includes an antireflection film or a polarizing plate excellent in the above characteristics, is excellent in antireflection performance, and is excellent in visibility and display quality.

In the specification of the present application, “to” is used in the sense of including the numerical values described before and after it as lower and upper limits. In addition, the term “on the support” or “alignment film” in the present invention refers to a direct surface of the support or the like, and a surface provided with any layer (film) on the support or the like. This is intended to include both cases.
Details of the present invention will be described below.
<Layer structure of antireflection film>
The antireflection film of the present invention is obtained by coating an antireflection film comprising at least one thin layer having a refractive index different from that of the transparent support on the transparent support. Next, typical preferred examples of the structure of the antireflection film of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing a layer structure when a multilayer antireflection film having excellent antireflection performance is used as a protective film on one side of a polarizing plate. The multilayer antireflection film 11 includes a transparent support 1 and an antireflection film 10 formed on the surface thereof, that is, a hard coat layer 2, a middle refractive index layer 3, a high refractive index layer 4, and a low refractive index layer (outermost layer) 5. The antireflection film 10 has a layer structure of the following order. The transparent support 1, the medium refractive index layer 3, the high refractive index layer 4, and the low refractive index layer 5 have refractive indexes that satisfy the following relationship.
Refractive index of high refractive index layer> refractive index of medium refractive index layer> refractive index of transparent support> refractive index of low refractive index layer

[Various properties of antireflection film]
[Relationship between refractive index and thickness of each layer]
In the layer structure as shown in FIG. 1, as described in JP-A-59-50401, the medium refractive index layer represents the following formula (2 ′), and the high refractive index layer represents the following formula (3 ′). The low refractive index layer preferably satisfies the following mathematical formula (4 ′) in that the antireflection film 11 having better antireflection performance can be produced.

Formula (2 ′): (m ₁ λ / 4) × 0.7 <n ₁ d ₁ <(m ₁ λ / 4) × 1.3
In the formula (2 ′), m ₁ is a positive integer (generally 1, 2 or 3), n ₁ is the refractive index of the medium refractive index layer, and d ₁ is the layer thickness ( nm). λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm.

Formula (3 ′): (m ₂ λ / 4) × 0.7 <n ₂ d ₂ <(m ₂ λ / 4) × 1.3
In the formula (3 ′), m ₂ is a positive integer (generally 1, 2 or 3), n ₂ is the refractive index of the high refractive index layer, and d ₂ is the thickness of the high refractive index layer ( nm). λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm.

Formula (4 ′): (m ₃ λ / 4) × 0.7 <n ₃ d ₃ <(m ₃ λ / 4) × 1.3
In formula (4 ′), m ₃ is a positive odd number (generally 1), n ₃ is the refractive index of the low refractive index layer, and d ₃ is the layer thickness (nm) of the low refractive index layer. . λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm.

In the layer configuration as shown in FIG. 1, it is particularly preferable that the middle refractive index layer satisfies the following formula (2), the high refractive index layer satisfies the following formula (3), and the low refractive index layer satisfies the following formula (4). . In addition, (lambda) here is a design wavelength and is 400-680 nm.
Formula (2): (λ / 4) × 0.80 <n ₁ d ₁ <(λ / 4) × 1.00
Formula (3): (λ / 2) × 0.75 <n ₂ d ₂ <(λ / 2) × 0.95
Formula (4): (λ / 4) × 0.95 <n ₃ d ₃ <(λ / 4) × 1.05

[Amount of scattered light from the antireflection film]
In the present invention, the light incident on the antireflection film surface from a specific direction is the total of the amount of scattered light in the specific direction and the total scattered light of the incident light among the scattered light scattered on the antireflection film surface. The quantity of light I satisfies the relationship of the following formula (1).
Formula (1): -Log (I ₅₀ /I)≧6.6.
The amount of scattered light can be measured using a goniophotometer “GP-5” {Murakami Color Research Laboratory Co., Ltd.}. A halogen lamp (12V, 50W) is used as the light source. I ₅₀ is the reflection in the direction tilted by + 50 ° from the normal line when the surface of the antireflection film is irradiated with light from the direction tilted by −10 ° from the normal line standing on the transparent support surface of the antireflection film. It is a light quantity value of scattered light. The total light quantity I of the total scattered light of the incident light is obtained using a standard white plate. This is the total light quantity value of the total reflected scattered light in the −85 ° to + 90 ° direction when the surface of the standard white plate is irradiated with light from the direction inclined by −10 ° from the normal line.

In the present invention, the value of -Log (I ₅₀ / I) needs to be 6.6 or more, preferably 6.7 or more, and more preferably 6.8 or more. -If the value of Log I ₅₀ / I is smaller than this value, the black display may appear white or black when the display is viewed from an oblique direction. Is not achieved.

[Surface roughness and average inclination angle of antireflection film]
The outermost surface of the antireflection film of the present invention has an arithmetic average roughness (Ra) of 0.1 to 15 nm, a ten-point average roughness / arithmetic average roughness (Rz / Ra) of 15 or less, and an average slope of the uneven profile. The angle (average inclination angle with respect to the regular reflection surface) is preferably 3 ° or less. More preferably, Ra is 0.1 to 10 nm, Rz / Ra is 12 or less, and an average inclination angle is 2.5 ° or less, more preferably, Ra is 0.5 to 10 nm, Rz / Ra is 10 or less, and average inclination. The angle is 2.0 ° or less, most preferably, Ra is 7 or less, and the average inclination angle is 2.0 ° or less. When each value of Ra, Rz / Ra, and average inclination angle is within the above ranges, the occurrence of whiteness due to the influence of surface irregularities is suppressed, and the visibility and display quality are improved.

The uneven shape on the surface of the antireflection film can be evaluated by a “Micromap” machine manufactured by RYOKA SYSTEM Co., Ltd. or a scanning probe microscope “SPI3800” {manufactured by Seiko Instruments Inc.}.
There are several other measuring apparatuses. As an example, a case where a scanning probe microscope “SPI3800” (manufactured by Seiko Instruments Inc.) is used will be described.

The average inclination angle is a height average value (angle converted value) of the change amount of the average radius of the island (the convex portion of the concavo-convex shape), and is specifically obtained by the following procedure.
(1) is determined the number N and the total area S _T island height Z.
(2) Obtain the average value S _V of the island area.
S _V = S _T / N
(3) Assuming that the island is a circle, an average value R _V of its radius is obtained.

(4) The steps (1) to (3) are repeated while changing the height Z, and the average radius R _V (Z) for each height Z is obtained.
(5) A change amount ΔR _V (Z) of R _V (Z) with respect to the minute height ΔZ is obtained and averaged by the total height H (= maximum height difference).

(6) Convert R _VH to the average inclination angle (Δa).
Δa = arctan (R _VH / ΔZ)

[Average specular reflectance, color]
The specular reflectance of incident light with an incident angle of 5 ° in the antireflection film of the present invention has an average value of 3.0% or less in the wavelength region from 450 nm to 650 nm. It is possible to prevent a decrease in visibility due to reflection of external light to a sufficient level. The average value of the specular reflectance is preferably 2% or less, more preferably 1% or less, and particularly preferably 0.8% or less.

Also, the color of specular reflection light with respect to an incident angle of 5 ° incident light CIE standard light source D ₆₅ in 780nm region from the wavelength 380nm is, a ^* of CIE1976L ^* a ^* b ^* color space, b ^* values, respectively -8 By satisfying ≦ a ^* ≦ 8 and within a range of −10 ≦ b ^* ≦ 10, the hue of reflected light from red purple to blue purple, which has been a problem in the conventional multilayer antireflection film, is reduced. Furthermore, by setting it within the range of 0 ≦ a ^* ≦ 6 and −8 ≦ b ^* ≦ 0, such a color is greatly reduced, and when applied to a liquid crystal display device, it looks like an indoor fluorescent lamp. Even when a little bright external light is reflected, the color is neutral and I don't care.

Specifically, if a ^* ≦ 8, the reddish color will not be too strong, and if a ^* ≧ −8, the cyan color will not be too strong, which is preferable. Furthermore, if b ^* ≧ −8, the bluish color does not become too strong, and if b ^* ≦ 0, the yellowish color does not become too strong, it is preferable.

The specular reflectance and color are measured by attaching an adapter “ARV-474” to a spectrophotometer “V-550” {manufactured by JASCO Corp.}, and an incident angle of 5 ° in the wavelength region of 380 to 780 nm. By measuring the specular reflectance at an exit angle of -5 °, the average reflectance of 450 to 650 nm is calculated, and the antireflection property can be evaluated. Furthermore, from the measured reflection spectrum, representing the color of specular reflection light with respect to an incident angle of 5 ° incident light CIE standard light source _{^{D 65, CIE1976L * a * b}} * color space of L ^* value, a ^* value, b ^* Values can be calculated and the color of reflected light can be evaluated.

[Refractive index of antireflection film]
The refractive index of the antireflection film is such that each refractive index layer is provided on an optical substrate such as a glass plate having a refractive index of 0.1 or more, and a spectrophotometer "V-550" {manufactured by JASCO Corporation} is an adapter " ARV-474 "is mounted, and the specular reflectance at an incident angle of -5 ° at an incident angle of 5 ° is measured in a wavelength region of 380 to 780 nm, and is obtained by fitting using a Couchy model.

  The difference in refractive index between the low refractive index layer and the layer adjacent to the low refractive index layer is preferably 0.16 to 1.3. More preferably, it is 0.18-1.2, More preferably, it is 0.20-1.0. If the difference in refractive index is 0.16 or more, sufficient antireflection properties can be obtained, and if the difference in refractive index is 1.3 or less, it is preferable to obtain appropriate materials.

<Transparent support>
The antireflection film of the present invention is formed by coating an antireflection film comprising at least one thin layer having a refractive index different from that of the transparent support on the transparent support. 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.

As the transparent support, a plastic film is preferable to a glass plate. Examples of plastic film materials include cellulose esters (eg, cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, 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, polyether Examples include imide, polymethyl methacrylate, and polyether ketone. Cellulose ester, polycarbonate, polyethylene terephthalate and polyethylene naphthalate are preferred.

  In particular, when used in a liquid crystal display device, a cellulose acylate film which is a fatty acid ester of cellulose among the above cellulose esters is preferable. Cellulose acylate is produced by esterifying cellulose. The cellulose used is usually used after purifying linter, kenaf, pulp or the like.

As described above, the cellulose acylate in the present invention is a fatty acid ester of cellulose, and a lower fatty acid ester is particularly preferable.
Here, the lower fatty acid means a fatty acid having 6 or less carbon atoms. A cellulose acylate having 2 to 4 carbon atoms is preferable, and cellulose acetate is particularly preferable. It is also preferable to use mixed fatty acid esters such as cellulose acetate propionate and cellulose acetate butyrate.

  The viscosity average degree of polymerization (DP) of cellulose acylate is preferably 250 or more, and more preferably 290 or more. Cellulose acylate preferably has a narrow molecular weight distribution of Mw / Mn (Mw is a mass average molecular weight, Mn is a number average molecular weight) by gel permeation chromatography. A specific value of Mw / Mn is preferably 1.0 to 5.0. More preferably, it is 1.0-3.0, Most preferably, it is 1.0-2.0.

  As the transparent support of the present invention, cellulose acylate having an acetylation degree of 55.0 to 62.5% is preferably used. The acetylation degree is more preferably 57.0 to 62.0%, and particularly preferably 59.0 to 61.5%. The degree of acetylation means the amount of bound acetic acid per unit mass of cellulose. The degree of acetylation is determined by measurement and calculation of the degree of acylation in ASTM: D-817-91 (testing method for cellulose acylate, etc.).

  In cellulose acylate, the hydroxyl groups at the 2-position, 3-position and 6-position of cellulose are not evenly substituted, but the substitution degree at the 6-position tends to be small. In the cellulose acylate used in the present invention, it is preferable that the degree of substitution at the 6-position of cellulose is the same or greater than that at the 2- and 3-positions. The ratio of the substitution degree at the 6-position to the total substitution degree at the 2-position, the 3-position, and the 6-position is preferably 30 to 40%, more preferably 31 to 40%, and more preferably 32 to 40%. Most preferably it is.

Various additives are added to the transparent support to adjust the mechanical properties (film strength, curl, dimensional stability, slipperiness, etc.) and durability (wet heat resistance, weather resistance, etc.) of the film. Can be used. For example, plasticizers (phosphate esters, phthalate esters, esters of polyols and fatty acids, etc.), UV inhibitors (eg, hydroxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, cyanoacrylate compounds) Etc.), deterioration inhibitors (eg, antioxidants, peroxide decomposers, radical inhibitors, metal deactivators, acid scavengers, amines, etc.), fine particles (eg, SiO ₂ , Al ₂ O ₃ , TiO ₂₎ , BaSO ₄ , CaCO ₃ , MgCO ₃ , talc, kaolin, etc.), release agents, antistatic agents, infrared absorbers, and the like.

  These details are disclosed in the Invention Association Public Technique No. 2001-1745 (issued March 15, 2001, Invention Association), p. Materials described in detail in 17-22 are preferably used. The amount of the additive used is preferably 0.01 to 20% by mass of the transparent support, and more preferably 0.05 to 10% by mass.

Surface treatment may be performed on the transparent support.
Examples of the 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, mixed acid treatment and ozone oxidation treatment. Specifically, for example, the contents described in pages 30 to 31 of the Japan Society of Invention and Innovation Technique No. 2001-1745 (issued on March 15, 2001), the contents described in Japanese Patent Application Laid-Open No. 2001-9973, and the like. It is done.
Preferably, glow discharge treatment, ultraviolet irradiation treatment, corona discharge treatment and flame treatment, and more preferably glow discharge treatment and ultraviolet treatment.

<Antireflection film>
(High refractive index layer)
The high refractive index layer in the present invention is also referred to as a curable composition (hereinafter also referred to as a high refractive index forming composition) containing inorganic compound fine particles having a high refractive index (hereinafter sometimes referred to as high refractive index fine particles) and a matrix binder. .) Is preferably formed of a cured film having a refractive index of 1.55 to 2.50. The refractive index is preferably 1.65 to 2.40, more preferably 1.70 to 2.20.

  Further, the surface of the high refractive index layer forms a fine surface irregularity with a size that does not optically affect, and the arithmetic average roughness of the surface irregularity of the high refractive index layer based on JIS B-0601-1994 ( Ra) is 0.001 to 0.03 [mu] m, further 0.001 to 0.015 [mu] m, especially 0.001 to 0.010 [mu] m; ten-point average roughness (Rz) is 0.001 to 0.06 [mu] m, Further, it is in the range of 0.002 to 0.05 μm, particularly 0.002 to 0.025 μm, and the maximum height (Ry) is 0.09 μm or less, further 0.05 μm or less, particularly 0.04 μm or less. It is preferable that

  Furthermore, in the fine surface irregularity form having a size that does not affect optically, the ratio (Rz / Ra) of arithmetic average roughness (Ra) to ten-point average roughness (Rz) is 15 or less, And it is preferable that the average space | interval (Sm) of the surface unevenness | corrugation of this high refractive index layer based on JISB-0601-1994 is 0.01-1 micrometer. Here, the relationship between Ra and Rz indicates the uniformity of surface irregularities. The (Rz / Ra) ratio is more preferably 12 or less, more preferably 7 or less, and the average interval (Sm) may be 0.01 to 0.8 μm. If it is in these ranges, the coated surface shape of the low refractive index layer coated on the high refractive index layer will be good with no unevenness or streaks, and whiteness will be improved. Furthermore, the adhesion between the two layers can be improved. The concave and convex shapes on the surface of the layer can be evaluated by an atomic force microscope (AFM).

  In order to make the high refractive index layer a high refractive index cured film having a refractive index of 1.55 to 2.50 in which high refractive index fine particles are dispersed in a matrix binder, the refractive index of the matrix binder is usually 1.4. Since the use ratio of the fine particles is determined by the refractive index of the fine particles used, it is preferably 40 to 80% by mass in the total mass of the cured film, more preferably 45 to 1.5%. 75% by mass.

Thus, in order to increase the film strength of the high refractive index layer designed by increasing the ratio of the high refractive index fine particles and to enhance the adhesion with the upper layer after providing the upper layer, it will be described later. As described above, a high-refractive-index fine particle having an ultrafine particle size and a uniform particle size is used, and this is uniformly dispersed in the high-refractive-index layer, and the surface of the layer is in an uneven state as described above. Is preferably formed. By making the shape and distribution of surface irregularities on the entire surface of the high refractive index layer into a specific range, even when a low refractive index layer is provided as an upper layer continuously to a long film, the entire surface of the layer is uniform and uniform. The anchoring effect is sufficiently exhibited, and the whiteness is improved and the adhesion is maintained, which is preferable. Moreover, even after storing for a long time, the adhesiveness is maintained without change, which is preferable.

  The adhesion between the cured film of the high refractive index layer in the present invention and the upper layer (low refractive index layer) coated on the high refractive index layer is 50 mg in the amount of abrasion in the Taber abrasion test based on JIS K-6902. In the following, it is further preferable to be 40 mg or less. The Taber abrasion test is specifically the amount of abrasion after 500 revolutions at a load of 1 kg. Within this range, scratch resistance as an antireflection film is sufficiently maintained, which is preferable.

  Further, in the antireflection film including the high refractive index layer formed with the surface shape, the number of luminance defects having a diameter of 50 μm or more that is easily noticeable as a foreign object is 20 or less per square meter. It is preferable to become.

[Composition for forming a high refractive index layer]
(High refractive index fine particles)
The high refractive index fine particles contained in the high refractive index layer in the present invention have a refractive index of 1.80 to 2.80, more preferably 1.90 to 2.80; an average primary particle size of 3 to 100 nm, It is preferably 5 to 100 nm, particularly 10 to 80 nm. If the refractive index of the high refractive index fine particles is 1.80 or more, the refractive index of the layer can be effectively increased, and if the refractive index is 2.80 or less, there is no inconvenience such as coloring of the particles, which is preferable. . Further, if the average particle diameter of the primary particles of the high refractive index fine particles is 100 nm or less, it is preferable because the haze value of the high refractive index layer to be formed is high and there is no inconvenience such as impairing the transparency of the layer. It is preferable because a high refractive index is maintained.
The particle diameter of the high refractive index fine particles is represented by an average primary particle diameter according to a transmission electron microscope (TEM) photograph. The average primary particle diameter is expressed as an average value of the maximum diameters of the respective fine particles. When the major axis diameter and the minor axis diameter are included, the average value of the major axis diameters of the respective fine particles is defined as the average primary particle diameter.

  Specific examples of preferable high refractive index fine particles include Ti, Zr, Ta, In, Nd, Sn, Sb, Zn, La, W, Ce, Nb, V, Sm, Y and other oxides or composite oxides, sulfides The particle | grains which have as a main component are mentioned. Here, the main component refers to a component having the largest content (% by mass) among the components constituting the particles. More preferable high refractive index fine particles in the present invention are particles mainly composed of an oxide or composite oxide containing at least one metal element selected from Ti, Zr, Ta, In, and Sn.

  The high refractive index fine particles used in the present invention may contain various elements in the particles (hereinafter, such elements may be referred to as containing elements). Examples of the contained element 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 an element such as Sb, Nb, P, B, In, V, or 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 high refractive index fine particles in the present invention are inorganic fine particles mainly composed of titanium dioxide containing at least one element selected from Co, Zr, and Al as contained elements (hereinafter referred to as “specific oxide”). Is also available). A particularly preferable element is Co. The total content of Co, Al and Zr is preferably 0.05 to 30% by mass with respect to Ti, more preferably 0.1 to 10% by mass, still more preferably 0.2 to 7% by mass, particularly Preferably it is 0.3-5 mass%, Most preferably, it is 0.5-3 mass%. Containing elements Co, Al,
Zr is present inside or on the surface of high refractive index fine particles mainly composed of titanium dioxide. It is more preferable that it exists inside the high refractive index fine particles mainly composed of titanium dioxide, and most preferable that it exists both inside and on the surface. Among these contained elements, the metal element may exist as an oxide.

  As another preferable high refractive index fine particle, a composite of titanium element and at least one metal element selected from metal elements whose oxide has a refractive index of 1.95 or more (hereinafter also abbreviated as “Met”). Inorganic fine particles which are oxide particles and the composite oxide is doped with at least one metal ion selected from Co ions, Zr ions and Al ions (sometimes referred to as “specific double oxide”) Is mentioned. Here, Ta, Zr, In, Nd, Sb, Sn, and Bi are preferable as the metal element whose refractive index of the oxide is 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%, Most preferably, it is 0.3-3 mass%.

  The doped metal ion may be present as a metal ion or in any form of metal atom, and may be appropriately present from the surface to the inside of the composite oxide. It is preferably present both on the surface and inside.

  The high refractive index fine particles used in the present invention preferably have a crystal structure. The crystal structure is preferably composed mainly of rutile, a mixed crystal of rutile / anatase, and anatase, and particularly preferably a rutile structure. Thereby, the high refractive index fine particles of the specific oxide or the specific double oxide have a refractive index of 1.90 to 2.80, which is preferable. The refractive index is more preferably 2.10 to 2.80, and still more preferably 2.20 to 2.80. In addition, this can suppress the photocatalytic activity of titanium dioxide, and can significantly improve the weather resistance of the high refractive index layer itself and the upper / lower layers in contact with the high refractive index layer in the present invention. ,preferable.

  A conventionally well-known method can be used for the method of doping the above-mentioned specific metal element or metal ion. For example, methods described in JP-A-5-330825, 11-263620, JP-A-11-512336, European Patent No. 0335773, etc .; ion implantation method [for example, Shunichi Gonda, Jun Ishikawa 3. Eiji Kamijo, “Ion Beam Application Technology” CMC Co., Ltd., published in 1989, Yasushi Aoki, “Surface Science” 18 (5), 262, 1998, Shoichi Anbo, “Surface Science” 20 (2), p. 60, 1999, etc.].

The high refractive index fine particles used in the present invention may be surface treated. Surface treatment is a modification of the particle surface using an inorganic compound and / or an organic compound. This adjusts the wettability of the surface of the high-refractive-index fine particles, and makes the particles fine in an organic solvent. The dispersibility and dispersion stability in the composition for forming the rate layer are improved. Examples of inorganic compounds that are physicochemically adsorbed on the particle surface include inorganic compounds containing silicon (such as SiO ₂ ), inorganic compounds containing aluminum [such as Al ₂ O ₃ and Al (OH) ₃ ], and cobalt. Inorganic compounds containing (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 the like.

  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, published in 2001).

  Specifically, an organic compound having a polar group having an affinity for the surface of the high refractive index fine particles and a coupling compound can be mentioned. Examples of the polar group having an affinity for the surface of the high refractive index fine particles include a carboxy group, a phosphono group, a hydroxy group, a mercapto group, a cyclic acid anhydride group, an amino group, etc., and a compound containing at least one kind in the molecule Is preferred. 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 (epichlorohydrin) modified glycerol triacrylate Etc.], phosphono group-containing compounds {for example, EO (ethylene oxide) -modified phosphate triacrylate, etc.}, alkanolamines {ethylenediamine EO adducts (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 contained. Silane coupling agents are most preferred. Specific examples include compounds described in paragraph numbers “0011” to “0015” in JP-A-2002-9908 and 2001-310423.
Two or more kinds of compounds used for these surface treatments can be used in combination.

  The high refractive index fine particles are also preferably fine particles having a core / shell structure in which a shell made of another inorganic compound is formed using the high refractive index 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 high refractive index fine particles 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 high refractive index fine particles may be used alone or in combination of two or more.

(Dispersant)
In order to use the high refractive index fine particles as stable predetermined ultrafine particles, it is preferable to use a dispersant together. The dispersant is preferably a low molecular compound or a high molecular compound having a polar group having affinity with the surface of the high refractive index 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) (OR ₁ ) (OH) group, and —O—P (═O) (OR 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 the same content as a hydrogen atom or 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 an aliphatic group having 1 to 12 carbon atoms (having the same contents as the above R ₁ or R ₂ group, etc. ) 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 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 capable of addition reaction / polymerization reaction by radical species [for example, (meth) acryloyl group, allyl group, styryl group, vinyloxy group carbonyl group, vinyloxy group, etc.], 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 the compounds described in paragraph numbers [0013] to [0015] in JP-A No. 2001-310423.

The dispersant used in the present invention is 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, but is preferably 1 × 10 ³ or more as a polystyrene equivalent value measured by 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 . A material in this range is preferable because a high-refractive-index fine particle is easily dispersed and a stable dispersion free from aggregates and precipitates can be obtained. Specific examples include the contents described in paragraph numbers [0024] to [0041] in JP-A-11-153703.

(Dispersion medium)
The dispersion medium used for wet dispersion of the high refractive index fine particles can be appropriately selected from water and an organic solvent, and is preferably a liquid having a boiling point of 50 ° C. or higher, and having a boiling point in the range of 60 to 180 ° C. More preferably, it is an organic solvent.

  The dispersion medium is preferably used in such a ratio that the total components for forming the high refractive index layer containing the high refractive index fine particles and the dispersant are 5 to 50% by mass. Furthermore, 10-30 mass% is preferable. In 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, esters, 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.), ester ( For example, 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), aromatic Group hydrocarbons (eg, benzene, toluene, xylene, etc.), amides (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone, etc.), ethers (
Examples thereof include dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, and the like) and ether alcohols (for example, 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. In addition, 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% of the total solvent contained in the composition for forming a high refractive index layer. % Or more is preferable. More preferably, it is 30 mass% or more, More preferably, it is 60 mass% or more.

(Making ultra-fine particles of high refractive index fine particles)
When the curable composition for forming a high refractive index layer used in the present invention is an ultrafine particle dispersion of an inorganic compound having an average primary particle size of 100 nm or less, the stability of the liquid of the composition is improved. The high refractive index layer, which is a cured film formed from this curable composition, has high refractive index fine particles uniformly dispersed in an ultra fine particle state in the matrix of the cured film, and has uniform optical properties and transparency. A high refractive index layer is formed. The size of the ultrafine particles present in the matrix of the cured film is preferably such that the average primary particle size is 3 to 100 nm, and more preferably 5 to 100 nm. In particular, 10 to 80 nm is most preferable. Furthermore, it is preferable that large particles with a particle diameter of primary particles of 200 nm or more are not included, and it is particularly preferable that large particles with a particle diameter of 150 nm or more are not included. This is preferable because the surface of the cured film of the high refractive index layer can have the above-described specific uneven shape. In addition, by incorporating high refractive index fine particles within the above-mentioned specific size range into the high refractive index layer, internal scattering caused by the high refractive index layer can be controlled, and "whiteness" is further improved. It is possible and preferable.

  In order to disperse the above high refractive index fine particles into the size of ultra fine particles not containing coarse particles in the above range, the dispersion is performed by a wet dispersion method using a medium having an average particle diameter of less than 0.8 mm together with the above-mentioned dispersant. Can be achieved.

  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 high refractive index fine particles used in the present invention in the ultra fine particles.

  As the media used together with the disperser, the average particle size is preferably less than 0.8 mm, and when the media has an average particle size within this range, the high refractive index fine particle size is 100 nm or less, and the particles Ultrafine particles with a uniform diameter can be obtained. The average particle size of the media is more preferably 0.5 mm or less, and even more preferably 0.05 to 0.3 mm. Moreover, as a medium used for wet dispersion, beads are preferable. Specific examples include zirconia beads, glass beads, ceramic beads, steel beads, etc., and 0.05 to 0.2 mm from the viewpoint of durability and ultrafine particle formation such that the beads are not easily broken during dispersion. Zirconia beads are particularly preferred.

  The dispersion temperature in the dispersion step is preferably 20 to 60 ° C, more preferably 25 to 45 ° C. This is preferable because dispersion in the ultrafine particles at a temperature in this range does not cause re-aggregation or precipitation of the dispersed particles. This is presumably because adsorption of the dispersant to the inorganic compound particles is appropriately performed and dispersion stability is not deteriorated due to desorption of the dispersant from the particles at room temperature. By carrying out the dispersion step in such a range, it is possible to form a high refractive index film excellent in refractive index uniformity, film strength, adhesion to an adjacent layer, etc. without impairing transparency.

  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 that the dispersed particles in the dispersion satisfy the above-mentioned range of the average particle diameter and the monodispersibility of the particle diameter, separation treatment with beads is performed in order to remove coarse aggregates in the dispersion. It is also preferable to arrange the filter medium so that it is microfiltered in The filter medium for fine filtration 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 microfiltration of the dispersion is not particularly limited as long as it has the above-described performance and does not adversely affect the resulting composition for forming a high refractive index layer. For example, stainless steel, polyethylene, polypropylene , Nylon and the like.

(Matrix of high refractive index layer)
The high refractive index layer preferably contains high refractive index fine particles and a matrix.

According to a preferred embodiment of the present invention, the matrix of the high refractive index layer is:
(A) an organic binder, or (B) an organometallic compound containing a hydrolyzable functional group and a partial condensate of this organometallic compound,
After applying a composition for forming a high refractive index layer containing at least one of the above, it is formed by curing.

(A) Organic binder As an organic binder,
(A) a conventionally known thermoplastic resin;
(B) a combination of a conventionally known reactive curable resin and a curing agent, or (c) a combination of a binder precursor (such as a curable polyfunctional monomer or polyfunctional oligomer described below) and a polymerization initiator,
The binder formed from is mentioned.

  It is preferable that a composition for forming a high refractive index layer is prepared from a dispersion containing the organic binder (a), (b) or (c) above, high refractive index fine particles and a dispersant. This composition is coated on a transparent support to form a coating film, and then cured by a method according to the component for forming a binder to form a high refractive index layer. The curing method is appropriately selected depending on the type of the binder component. For example, a crosslinking reaction or a polymerization reaction of a curable compound (for example, a polyfunctional monomer or a polyfunctional oligomer) is performed by at least one of heating and light irradiation. The method to make it occur is mentioned. 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 fine particles simultaneously with or after the application of the composition for forming a high refractive index layer.

  The binder in the cured film produced in this way is, for example, the above-mentioned dispersant and a curable polyfunctional monomer or polyfunctional oligomer that is a precursor of the binder undergoes a crosslinking or polymerization reaction, and the binder contains the dispersant. An anionic group is incorporated. Furthermore, since the binder in the cured film has a function of maintaining the dispersion state of the high refractive index fine particles, the crosslinked or polymerized structure imparts a film forming ability to the binder and contains the high refractive index fine particles. The physical strength, chemical resistance, and weather resistance in the cured film can be improved.

{Thermoplastic resin (A-i)}
Examples of the thermoplastic resin (a) include polystyrene resin, polyester resin, cellulose resin, polyether resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl copolymer resin, polyacrylic resin, and polymethacrylic resin. Examples thereof include resins, polyolefin resins, urethane resins, silicone resins, imide resins, and the like.

{Combination of reactive curable resin and curing agent (A-B)}
In addition, as the reactive curable resin (b), 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 cocondensation 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 necessary for these reactive curable resins, a crosslinking agent (epoxy compound, polyisocyanate compound, polyol compound, polyamine compound, melamine compound, etc.), polymerization initiator (azobis compound, organic peroxide compound, organic halogen compound, Conventionally known compounds such as curing agents such as onium salt compounds and UV photoinitiators such as 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).

{Combination of binder precursor and polymerization initiator (A-C)}
Hereinafter, a method for forming a cured binder by crosslinking or polymerizing a curable compound by light irradiation using the combination of (c), which is a preferable method for forming a cured binder, will be mainly described.

  The functional group of the photocurable polyfunctional monomer or polyfunctional oligomer that is the precursor of the binder may be either radically polymerizable or cationically polymerizable.

  Examples of the radical polymerizable functional group include an ethylenically unsaturated group 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 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 include esters of unsaturated carboxylic acids and aliphatic polyhydric alcohol compounds, and 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 yet 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. Polymerizable ester compounds (monoesters or polyesters) of these aliphatic polyhydric alcohol compounds and unsaturated carboxylic acids, for example, compounds described in paragraph numbers [0026] to [0027] of JP-A-2001-139663, for example Is mentioned.

  Examples of other polymerizable esters include, for example, vinyl methacrylate, allyl methacrylate, allyl acrylate, fats described in JP-B-46-27926, JP-B-51-47334, JP-A-57-196231, and the like. Aromatic alcohol 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 aliphatic polyvalent amine compounds and unsaturated carboxylic acids include methylene bis (meth) acrylamide, 1,6-hexamethylene bis (meth) acrylamide, and diethylenetriamine tris (meth) acrylamide. And xylylene bis (meth) acrylamide, and those having a cyclohexylene structure described in JP-B No. 54-21726.

Furthermore, vinylurethane compounds containing two 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 Described in JP-B-62-39418, polyester acrylates (JP-B 52-30490, etc.), and further, described in Japan Adhesion Association Vol. 20, No. 7, pages 300-308 (1984). Photocurable monomers and oligomers can also be used.
Two or more kinds of these radical polymerizable polyfunctional monomers may be used in combination.

  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, a vinyl hydrocarbon compound, and a vinyl ether compound. In the present invention, one or more of the above cationic 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 the compound is 3000 or less,
Preferably it is the range of 200-2000, Most preferably, it is the range of 400-1500. If the molecular weight is equal to or higher than the lower limit, there is no inconvenience such as a problem of volatilization during the film formation process. If the molecular weight is equal to or lower than the upper limit, compatibility with the composition for forming a high refractive index layer is not caused. Is preferable because it does not cause problems such as deterioration.

  Examples of the epoxy compound include aliphatic epoxy compounds and aromatic epoxy compounds.

  Examples of the aliphatic epoxy compound 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 epoxide stearate, octyl epoxide stearate, epoxidized linseed oil, epoxidized polybutadiene, etc. Can be mentioned. Examples of the alicyclic epoxy compound include polyglycidyl ethers of polyhydric alcohols having at least one alicyclic ring, or unsaturated alicyclic rings (for example, cyclohexene, cyclopentene, dicyclooctene, tricyclodecene, etc. ) Cyclohexene oxide or cyclopentene oxide-containing compound obtained by epoxidizing the containing compound with a suitable oxidizing agent such as hydrogen peroxide or peracid.

  Examples of the aromatic epoxy compound include monovalent or polyvalent phenol having at least one aromatic nucleus, or mono- or polyglycidyl ether of an alkylene oxide adduct 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.

  Among these epoxy compounds, aromatic epoxides and alicyclic epoxides are preferable, and alicyclic epoxides are particularly preferable in consideration of fast curability. 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 having a thioepoxy ring instead of the epoxy ring of the epoxy compound.

  Specific examples of the compound containing an oxetanyl group as a cyclic ether include the compounds described in paragraphs [0024] to [0025] in JP-A No. 2000-239309. These compounds are preferably used in combination with an epoxy group-containing 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 (vinyl cyclohexane, vinyl bicycloheptene, etc.), compounds described in the above radical polymerizable monomers, propenyl compounds {"J. Polymer Science: Part A". : Polymer Chemistry ", vol. 32, p. 2895 (1994), etc.}, alkoxy allene compounds {" J. Polymer Science: Part A:
Polymer Chemistry ", 33, 2493 (1995), etc.}, vinyl compounds {" J. Polymer Science: Part A: Polymer
r Chemistry ", 34, 1015 (1996), JP-A-2002-29162, etc.}, isopropenyl compound {" J. Polymer Science: Part A: Polymer Chemistry ", Vol. 34, page 2051 (1996), etc.}.
You may use these in combination of 2 or more types as appropriate.

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

  The radical polymerizable compound and the cationic polymerizable compound described above are preferably contained in a mass ratio of radical polymerizable compound: cation polymerizable compound in a ratio of 90:10 to 20:80, and 80:20 It is more preferable to contain in the ratio of -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 is preferably a compound that generates radicals or acids upon irradiation with light and / or heat. The photopolymerization initiator 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, compounds that generate radicals will be described in detail.
The compound that generates radicals preferably used in the present invention refers to a compound that generates radicals by irradiation with light and / or heat and initiates and accelerates polymerization of a compound having a polymerizable unsaturated group. 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 which generate | occur | produces a radical can be used individually or in combination of 2 or more types.

  Examples of the compound that generates radicals include conventionally known organic peroxide compounds, thermal radical polymerization initiators such as azo polymerization initiators, organic peroxide compounds (JP 2001-139663 A, etc.), amine compounds (special No. 44-20189), metallocene compounds (JP-A-5-83588, JP-A-1-304453, etc.), hexaarylbiimidazole compounds (US Pat. No. 3,479,185, etc.) ), Disulfone compounds (JP-A-5-239015, JP-A-61-166544, etc.), organic halogenated compounds, carbonyl compounds, organic boric acid compounds, and the like.

Specific examples of the organic halogenated compound include Wakabayashi et al., “Bull. Chem.
Soc Japan ", 42, 2924 (1969), U.S. Pat. No. 3,905,815, JP-A-5-27830, MP Hutt," J. Heterocyclic Chemistry ", Vol. 1 (No. 3), (1970)" and the like, and in particular, an oxazole compound substituted with a trihalomethyl group: s-triazine compound. More preferable examples include s-triazine derivatives in which at least one mono, di, or trihalogen-substituted methyl group is bonded to the s-triazine ring.

  Examples of the carbonyl compound include, for example, “Latest UV Curing Technology”, pages 60 to 62 [published by Technical Information Association, 1991], Japanese Patent Application Laid-Open No. 8-134404, paragraph numbers [0015] to [0016], 11-217518, the compounds described in paragraphs [0029] to [0031] and the like, and benzoin compounds such as acetophenone, hydroxyacetophenone, benzophenone, thioxan, benzoin ethyl ether, benzoin isobutyl ether, p -Benzoic acid ester derivatives such as ethyl dimethylaminobenzoate and ethyl p-diethylaminobenzoate, benzyldimethyl ketal, acylphosphine oxide and the like.

  Examples of the organic borate compounds include, for example, Japanese Patent Nos. 2764769 and 2002-116539, and Kunz, Martin, “Rad. Tech '98. Proceeding April 19-22, 1998, Chicago”. And the organic borates described in the above. Examples thereof include compounds described in paragraph numbers [0022] to [0027] of JP-A-2002-116539. Examples of other organic boron compounds include JP-A-6-348011, JP-A-7-128785, JP-A-7-140589, JP-A-7-306527, and JP-A-7-292014. Specific examples include organoboron transition metal coordination complexes.

  These radical generating compounds may be added alone or in combination of two or more. As addition amount, it is 0.1-30 mass% with respect to the whole quantity of a radically polymerizable monomer, Preferably it is 0.5-25 mass%, Most preferably, it can add at 1-20 mass%. Within this range, the high-refractive index layer-forming composition exhibits high polymerizability without problems with time.

Next, a photoacid generator that can be used as a photopolymerization initiator will be described in detail.
Examples of the acid generator include a photoinitiator for photocationic polymerization, a photodecolorant for dyes, a photochromic agent, a known acid generator used in a microresist, and the like, a known compound, and a mixture thereof. Is mentioned. Examples of the acid generator include organic halogenated compounds, disulfone compounds, onium compounds, etc. Among these, specific examples of organic halogen compounds and disulfone compounds are the same as those described for the compound that generates radicals. Things.

  Examples of the onium compounds include diazonium salts, ammonium salts, iminium salts, phosphonium salts, iodonium salts, sulfonium salts, arsonium salts, selenonium salts, and the like, for example, paragraph numbers [0058] to [0059] of JP-A-2002-29162. And the like.

  As the acid generator, an onium salt is particularly preferably used, and among them, a diazonium salt, an iodonium salt, a sulfonium salt, and an iminium salt are preferable from the viewpoint of photosensitivity at the start of photopolymerization, material stability of the compound, and the like.

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

Other examples of the acid generator include organometallic / organic halides described in JP-A-2002-29162, paragraphs [0059] to [0062], and a photoacid generator having an o-nitrobenzyl type protecting group. And compounds such as compounds that generate photosulfonic acid to generate sulfonic acid (iminosulfonate, etc.).

  These acid generators may be used alone or in combination of two or more. These acid generators may be added in a proportion of 0.1 to 20% by mass, preferably 0.5 to 15% by mass, particularly preferably 1 to 10% by mass, based on the total mass of the total cationically polymerizable monomer. it can. When the addition amount is in the above range, it is preferable from the viewpoint of stability, polymerization reactivity, etc. of the composition for forming a high refractive index layer.

  The composition for forming a high refractive index layer in the present invention is 0.5 to 10% by mass of the radical polymerization initiator or 1 to 10 of the cationic polymerization initiator based on the total mass of the radical polymerizable compound or the cationic polymerizable compound. It is preferable to contain in the ratio of the mass%. More preferably, it contains 1 to 5% by mass of a radical polymerization initiator or 2 to 6% by mass of a cationic polymerization initiator.

  In the composition for forming a high refractive index layer used in the present invention, when a polymerization reaction is carried out by ultraviolet irradiation, a conventionally known ultraviolet spectral sensitizer and chemical sensitizer may be used in combination. Examples of these sensitizers 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 range of 700 nm or more, and a compound having a molecular extinction coefficient of 10,000 or more is preferable. Furthermore, a value having absorption in the region of 750 to 1400 nm and a molecular extinction coefficient of 20000 or more is preferable. 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. Commercially available dyes and literature {for example, “Chemical Industry”, May 1986, pages 45-51, “Near-Infrared Absorbing Dye”, “Development and Market Trends of Functional Dyes in the 1990s”, Chapter 2.3. (1990) CMC, “Special Function Dye” [edited by Ikemori and Pilatani, 1986, issued by CMC Co., Ltd.], J. Am. FABIAN, “Chem. Rev.”, Vol. 92, pp. 1197-1226 (1992)}, a catalog published in 1995 by Nippon Sensitive Dye Research Laboratories, and Exciton Inc. Can be used as well as known dyes described in laser dye catalogs and patents issued in 1989.

(B) Organometallic compound containing hydrolyzable functional group and partial condensate of this organometallic compound As the 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 (2) and a partial hydrolyzate (partial condensate) thereof. In addition, it is a well-known fact that the organosilicon compound represented by the general formula (2) is easily hydrolyzed and subsequently undergoes a dehydration condensation reaction.

Formula (2): (R ²¹ ) β-Si (Y ²¹ ) _4- β
In the general formula (2), R ²¹ represents a substituted or unsubstituted aliphatic group having 1 to 30 carbon atoms or an aryl group having 6 to 14 carbon atoms. Y ²¹ represents a halogen atom (a chlorine atom, a bromine atom or the like), an OH group, an OR ²² group, or an OCOR ²² group. Here, R ²² represents a substituted or unsubstituted alkyl group. β represents an integer of 0 to 3, preferably 0, 1 or 2, particularly preferably 1. However, when β is 0, Y ²¹ represents an OR ²² group or an OCOR ²² group.

In the general formula (2), the aliphatic group represented by R ²¹ 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 ²¹ include phenyl, naphthyl, anthranyl and the like, and a phenyl group is preferable.

  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).

  Of 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 {( (Meth) acryloyl}, a polymerizable acylamino group (acrylamino, methacrylamino). These substituents may be further substituted.

As described above, R ²² represents a substituted or unsubstituted alkyl group, and the alkyl group is not particularly limited, and examples thereof include the same as the aliphatic group of R ²¹ , and the explanation of the substituent in the alkyl group is R Same as ²¹ .

  As for content of the compound of General formula (2), 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 (2) include, for example, 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. It is preferable that the binder has a silanol group because 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, or a high refractive index fine particle as a binder forming component constituting a coating composition for forming a high refractive index layer. An organosilicon compound represented by the general formula (2) having a crosslinkable or polymerizable functional group is blended in the coating composition together with a dispersant contained in the dispersion, and the coating composition is coated on a transparent support. Then, the dispersant, the polyfunctional monomer, the polyfunctional oligomer, and the organosilicon compound represented by the general formula (2) can be introduced into the binder by a crosslinking reaction or a 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 of β-diketones and 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 composition is 0.01 to 50% by mass, preferably 0.1 to 50% by mass, and more preferably 0.5 to 10% by mass with respect to the organometallic compound. 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 specified as a cured film forming component by, for example, blending a dispersion containing high refractive index fine particles and a dispersant in a coating composition for forming a high refractive index layer. A combination of 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 a cross-linked or polymerizable functional group At least one of the organosilicon compounds represented by the general formula (2) having, and, if desired, a monofunctional monomer having a specific polar group and a crosslinkable or polymerizable functional group, The coating composition is coated on a transparent support, and the above dispersant, monofunctional monomer, polyfunctional monomer or polyfunctional oligomer and / or the organosilicon compound represented by the general formula (2) is crosslinked or polymerized. To be obtained by.

  A monofunctional monomer having a specific polar group is preferable because it can function as a dispersion aid for the high refractive index fine particles in the coating composition. Furthermore, after coating, a uniform dispersion of high refractive index fine particles in the high refractive index layer is maintained by crosslinking or polymerization reaction with a dispersant, polyfunctional monomer or polyfunctional oligomer, or a polymerization reaction. A high refractive index layer excellent in physical strength, chemical resistance and weather resistance can be produced.

  It is preferable that the usage-amount with respect to the dispersing agent of the monofunctional monomer which has an amino group or a quaternary ammonium group is 0.5-50 mass%, More preferably, it is 1-30 mass%. If the binder is formed by crosslinking or polymerization reaction at the same time as or after the coating of the high refractive index layer, the monofunctional monomer can function effectively before the coating of the high refractive index layer.

The matrix of the high refractive index layer in the present invention corresponds to (b) of the above-mentioned organic binder and includes those cured and formed from a conventionally known organic polymer containing a crosslinked or polymerizable functional group. . The polymer after the formation of the high refractive index layer preferably has a structure that is further crosslinked or polymerized. Examples of the polymer include polyolefin (made of saturated hydrocarbon), polyether, polyurea, polyurethane, polyester, polyamine, polyamide and melamine resin. Of 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 and a repeating unit having a crosslinked or polymerized structure, as described above. 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 proportion thereof 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 proportion 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 coating the composition for forming a high refractive index layer on a transparent support and performing crosslinking or polymerization reaction simultaneously with or after coating.

(Other composition of high refractive index layer)
In the high refractive index layer of the present invention, other compounds can be appropriately added depending on the application and purpose. 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 element such as a chemical element {eg, bromine (Br), iodine (I), chlorine (Cl), etc.}, sulfur (S), nitrogen (N), phosphorus (P), etc. is contained, the refractive index of the organic compound increases. Therefore, binders obtained by crosslinking or polymerization reaction such as curable compounds containing them can also be preferably used.

  In the high refractive index layer, in addition to the above components (high refractive index fine particles, polymerization initiator, sensitizer, etc.), resin, surfactant, antistatic agent, coupling agent, thickener, anti-coloring agent, Colorants (pigments, dyes), antifoaming agents, leveling agents, flame retardants, UV absorbers, infrared absorbers, adhesion-imparting agents, polymerization inhibitors, antioxidants, surface modifiers, conductive metal fine particles, etc. It can also be added.

[Formation of high refractive index layer]
The high refractive index layer is preferably constructed by applying the above-described composition for forming a high refractive index layer on the transparent support directly or via another layer. The coating liquid for forming a high refractive index layer used in the present invention is obtained by mixing and diluting a high refractive index fine particle dispersion, a matrix binder liquid, and additives used as necessary in 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 filtration, a filter having an absolute filtration accuracy of 0.1 to 100 μm, more preferably 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 filter at a filtration pressure of 1.5 MPa (15 kgf / cm ² ) or less, further 1 MPa (10 kgf / cm ² ) or less, particularly 0.2 MPa (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 filter medium as described above in (Ultrafine particles of high refractive index fine particles) can be used. 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 formed on the above transparent support by the dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method. It can be prepared by coating by a known thin film forming method such as 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 source, and ultra-high pressure, high pressure, medium pressure, 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 a near infrared light source is used, it may be used in combination with an ultraviolet light source, or light may be irradiated from the transparent support 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 in a uniform cured state is obtained.

In the case of radical photopolymerization by light irradiation, it can be carried out in air or in an inert gas, but in order to shorten the polymerization induction period of the radically polymerizable monomer or sufficiently increase the polymerization rate, etc. It is preferable that the atmosphere has a reduced oxygen concentration. 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 hardness of the high refractive index 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 K-5400. Further, the scratch resistance of the high refractive index layer is preferably as the wear amount of the test piece coated with the high refractive index layer before and after the test is smaller in the Taber test according to JIS K-5400. 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.

  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, 0.5 to 10 μm is preferable, more preferably 1 to 7 μm, and particularly preferably 2 to 5 μm.

(Medium refractive index layer)
As described above, the antireflection film in the present invention preferably has a medium refractive index layer. That is, it is preferable to have a layer structure in the order of the middle refractive index layer 3, the high refractive index layer 4, and the low refractive index layer (outermost layer) 5. The middle refractive index layer has a refractive index intermediate between the refractive index of the transparent support and the refractive index of the high refractive index layer. Thus, the refractive index of each refractive index layer is relative. The medium refractive index layer is formed by coating the medium refractive index layer forming composition in the same manner as the high refractive index layer.

  The material constituting the middle refractive index layer in the present invention may be any conventionally known material, but it is preferable to use the same material as the high refractive index layer. 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.

(Low refractive index layer)
The low refractive index layer in the present invention is preferably a cured film formed by coating a thermosetting and light or radiation (for example, ionizing radiation) curable composition. The low refractive index layer in the present invention is preferably constructed as an outermost layer having scratch resistance and antifouling properties. From the viewpoint of expressing the antifouling effect, the cured film is preferably a cured film of a crosslinkable fluorine-containing polymer. If the fluoropolymer is 50% by mass or more with respect to the total mass of the outermost layer, the entire film surface is preferable since it exhibits stable characteristics without unevenness. Further, the low refractive index layer is composed of inorganic compound fine particles, a repeating unit derived from a fluorine-containing vinyl monomer and a repeating unit having a (meth) acryloyl group in the side chain as a matrix binder. It is preferably formed by a cured film of a combination (hereinafter sometimes referred to as a functional fluorine-containing polymer). The component derived from the copolymer more preferably occupies 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more of the solid content of the low refractive index layer film. From the viewpoint of achieving both low refractive index and film hardness, a curing agent such as polyfunctional (meth) acrylate is also preferably used in an addition amount within a range that does not impair the compatibility.

  The refractive index of the low refractive index layer is preferably 1.20 to 1.49, more preferably 1.25 to 1.48, and particularly preferably 1.30 to 1.46.

[Composition for forming a low refractive index layer]
(Functional fluorine-containing polymer)
The functional fluorine-containing polymer used for the low refractive index layer of the present invention will be described below.
Examples of the fluorine-containing vinyl monomer include fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, etc.), partial (meth) acrylic acid or fully fluorinated alkyl ester derivatives [for example, “Biscoat 6FM” { Osaka Organic Chemical Industry Co., Ltd.} or "M-2020" {Daikin Kogyo Co., Ltd.}, etc.], fully or partially fluorinated vinyl ethers, and the like, preferably perfluoroolefins and refractive index. From the viewpoints of solubility, transparency, availability, etc., hexafluoropropylene is particularly preferable.

  Increasing the composition ratio of these fluorine-containing vinyl monomers can lower the refractive index, but the film strength tends to decrease. In the present invention, the fluorine-containing vinyl monomer is preferably introduced so that the fluorine content of the copolymer is 20 to 60% by mass, more preferably 25 to 55% by mass, and particularly preferably 30 to 50%. This is a case of mass%.

The functional fluorine-containing polymer used in the present invention preferably has a repeating unit having a (meth) acryloyl group in the side chain as an essential component. When the composition ratio of these (meth) acryloyl group-containing repeating units is increased, the film strength is improved, but the refractive index tends to be increased. Generally, the (meth) acryloyl group-containing repeating unit preferably occupies 5 to 90% by mass, although it varies depending on the type of repeating unit derived from the fluorine-containing vinyl monomer.
It is more preferable to occupy 0-70 mass%, and it is especially preferable to occupy 40-60 mass%.

  In the functional fluorine-containing polymer useful in the present invention, in addition to the repeating unit derived from the fluorine-containing vinyl monomer and the repeating unit having a (meth) acryloyl group in the side chain, adhesion to a substrate, polymer Tg (film) Other vinyl monomers can be appropriately copolymerized from various viewpoints such as solubility in solvents, transparency, slipperiness, dustproof / antifouling properties, etc. A plurality of these vinyl monomers may be combined depending on the purpose, and are preferably introduced in the range of 0 to 65 mol% in the copolymer in total, and in the range of 0 to 40 mol%. More preferably, it is particularly preferably in the range of 0 to 30 mol%.

  The vinyl monomer unit that can be used in combination is not particularly limited. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, acrylic acid) 2-ethylhexyl, 2-hydroxyethyl acrylate), methacrylic acid esters (methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-hydroxyethyl methacrylate, etc.), styrene and its derivatives (styrene, p-hydroxymethylstyrene) , P-methoxystyrene, etc.), vinyl ethers (methyl vinyl ether, ethyl vinyl ether, cyclohexyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, etc.), vinyl esters (vinegar) Vinyl, vinyl propionate, vinyl cinnamate, etc.), unsaturated carboxylic acids (acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, etc.), acrylamides (N, N-dimethylacrylamide, Nt-butylacrylamide) N-cyclohexylacrylamide, etc.), methacrylamides (N, N-dimethylmethacrylamide), acrylonitrile and the like.

  A preferred embodiment of the functional fluorine-containing polymer used in the present invention is a compound represented by the following general formula (3).

  In formula (3), component [F] represents the following component (pf1), component (pf2), or component (pf3).

In the component (pf1), R ³¹ represents an F atom or a C 1-3 perfluoroalkyl group.

In the component (pf2), R ³² and R ³³ may be the same or different and each represents a fluorine atom or a —C _j F _{2j + 1} group, j is an integer of 1 to 4 (preferably j is 1 or 2). ). a1 represents 0 or 1, and a2 represents an integer of 2 to 5. a3 represents 0 or 1; When a1 and / or a3 are 0, each represents a single bond.

In the component (pf3), R ³⁴ and R ³⁵ each represent a fluorine atom or a —CF ₃ group. a1 and a3 represent 0 or 1 similarly to the said component (pf2). a4 represents 0 or an integer of 1 to 4, a5 represents 0 or 1, and a6 represents 0 or an integer of 1 to 5. When a3, a4, a5 and / or a6 are 0, each represents a single bond. (A4 + a5 + a6) is an integer in the range of 1-6.

In the general formula (3), X ³² represents a linking group having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, particularly preferably 2 to 4 carbon atoms, and has a branched structure even if it is a straight chain. It may also have a ring structure. Further, it may have a heteroatom selected from O, N and S. Preferred examples of the linking group B include * — (CH ₂ ) ₂ —O — **, * — (CH ₂ ) ₂ —NH — **, * — (CH ₂ ) ₄ —O — **, * — (CH ₂ ) ₆ —O — **, * — (CH ₂ ) ₂ —O— (CH ₂ ) ₂ —O — **, * —CONH— (CH ₂ ) ₃ —O — **, * —CH ₂ CH (OH) CH ₂ —O — **, * —CH ₂ CH ₂ OCONH (CH ₂ ) ₃ —O — ** {where, * represents a connecting site on the polymer main chain side, and ** represents ( Represents a linking site on the (meth) acryloyl group side. } Etc. are mentioned. u represents 0 or 1;

In the general formula (3), Y ³¹ represents a hydrogen atom or a methyl group. From the viewpoint of curing reactivity, a hydrogen atom is more preferable.

Further, in the general formula (3), X ³¹ represents a repeating unit derived from an arbitrary vinyl monomer, and is not particularly limited as long as it is a constituent component of a monomer copolymerizable with the monomer corresponding to the component [F]. From various viewpoints such as adhesion to the lower layer of the low refractive index layer, for example, the high refractive index layer, Tg of the polymer (contributing to film hardness), solubility in solvents, transparency, slipperiness, dustproof / antifouling properties, etc. It can select suitably and may be comprised by the single or several vinyl monomer according to the objective.

Preferred examples of X ³¹ in the general formula (3) include vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, and allyl vinyl ether. Vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate; methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, allyl (meth) acrylate, (meth) acryloyl (Meth) acrylic acid esters such as oxypropyltrimethoxysilane; styrene such as styrene and p-hydroxymethylstyrene, and Derivatives; crotonic acid, maleic acid, can be cited and unsaturated carboxylic acids and derivatives thereof such as itaconic acid, more preferably a vinyl ether derivative, vinyl ester derivatives, particularly preferably a vinyl ether derivative.

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

  Particularly preferably, in the general formula (3), the component [F] is the component (pf1), specifically, compounds described in paragraph numbers “0043” to “0047” of JP-A-2004-45462, etc. Is mentioned.

(Organosilane compound)
Moreover, as a low refractive index layer, it is preferable to use together with the functional fluorine-containing polymer described above, a hydrolyzate of an organosilane compound represented by the general formula (1) and / or a partial condensate thereof.

Next, the organosilane compound represented by the general formula (1) will be described.
General formula (1): (R ¹¹ ) α-Si (Y ¹¹ ) _4- α

In the general formula (1), R ¹¹ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. The alkyl group preferably has 1 to 30 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 6 carbon atoms, and examples thereof include methyl, ethyl, propyl, isopropyl, hexyl, decyl, hexadecyl and the like. . Examples of the aryl group include phenyl and naphthyl, and a phenyl group is preferable.

Y ¹¹ represents a hydroxyl group or a hydrolyzable group, for example, an alkoxy group (preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group or an ethoxy group), a halogen atom (for example, Cl, Br, I And a group represented by R ¹² COO (R ¹² is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, such as CH ₃ COO, C ₂ H ₅ COO, etc.), preferably Is an alkoxy group, particularly preferably a methoxy group or an ethoxy group.
α represents an integer of 1 to 3, preferably 1 or 2, and particularly preferably 1.

When R ¹¹ or the Y ¹¹ there are a plurality, a plurality of R ¹¹ or Y ¹¹ may be different even in the same, respectively.

The substituent contained in R ¹¹ is not particularly limited, but a halogen atom (fluorine, chlorine, bromine, etc.), hydroxyl group, mercapto group, carboxyl group, epoxy group, alkyl group (methyl, ethyl, i-propyl, propyl, t-butyl etc.), aryl groups (phenyl, naphthyl etc.), aromatic heterocyclic groups (furyl, pyrazolyl, pyridyl etc.), alkoxy groups (methoxy, ethoxy, i-propoxy, hexyloxy etc.), aryloxy (phenoxy etc.) ), Alkylthio groups (methylthio, ethylthio, etc.), arylthio groups (phenylthio, etc.), alkenyl groups (vinyl, 1-propenyl, etc.), acyloxy groups (acetoxy, acryloyloxy, methacryloyloxy, etc.), alkoxycarbonyl groups (methoxycarbonyl, ethoxy) Carbonyl, etc.), aryloxy Carbonyl groups (phenoxycarbonyl, etc.), carbamoyl groups (carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-methyl-N-octylcarbamoyl, etc.), acylamino groups (acetylamino, benzoylamino, acrylicamino, methacrylamino) Etc.), and these substituents may be further substituted.

When there are a plurality of R ¹¹ , at least one is preferably a substituted alkyl group or a substituted aryl group.

  Among the organosilane compounds represented by the general formula (1), an organosilane compound having a vinyl polymerizable substituent represented by the following general formula (1-1) is preferable.

In the general formula (1-1), R ¹¹² represents a hydrogen atom, a methyl group, a methoxy group, an alkoxycarbonyl group, a cyano group, a fluorine atom, or a chlorine atom. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group. A hydrogen atom, a methyl group, a methoxy group, a methoxycarbonyl group, a cyano group, a fluorine atom, and a chlorine atom are preferable, a hydrogen atom, a methyl group, a methoxycarbonyl group, a fluorine atom, and a chlorine atom are more preferable, and a hydrogen atom and a methyl group Is particularly preferred.

X ¹¹¹ represents a single bond or * -COO-**, * -CONH-** or * -O-**, preferably a single bond, * -COO-** or * -CONH-**, Bonds and * -COO-** are more preferred, and * -COO-** is particularly preferred. Here, * represents a position bonded to ═C (R ¹¹² ) —, and ** represents a position bonded to X ¹¹² .

^X112 represents a divalent linking chain. Specifically, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group having a linking group (for example, ether, ester, amide, etc.) inside, and a linking group inside. A substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, an alkylene group having a linking group therein is preferred, an unsubstituted alkylene group, an unsubstituted arylene group Further, an alkylene group having an ether or ester linking group inside is more preferred, an unsubstituted alkylene group, and an alkylene group having an ether or ester linking group inside is particularly preferred. Examples of the substituent include a halogen, a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group, and an aryl group, and these substituents may be further substituted.

α represents 0 or 1. When Y ¹¹ there are a plurality, it may be different even multiple Y ¹¹ are the same respectively. α is preferably 0. R ¹¹¹ has the same meaning as R ¹¹ in formula (1), preferably a substituted or unsubstituted alkyl group or an unsubstituted aryl group, and more preferably an unsubstituted alkyl group or an unsubstituted aryl group. Y ¹¹ represents the same as in general formula (1), preferably a halogen atom, a hydroxyl group, or an unsubstituted alkoxy group, more preferably a chlorine atom, a hydroxyl group, or an unsubstituted alkoxy group having 1 to 6 carbon atoms, a hydroxyl group, a carbon atom A C 1-3 alkoxy group is more preferable, and a methoxy group is particularly preferable.

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

  Of these compounds represented by the general formula (1) or the general formula (1-1), particularly preferable ones include 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and the like. It is done.

The hydrolyzate and / or partial condensate of an organosilane compound is generally produced by treating the organosilane compound in the presence of a catalyst. Catalysts include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid; organic acids such as oxalic acid, acetic acid, formic acid, methanesulfonic acid and toluenesulfonic acid; inorganic bases such as sodium hydroxide, potassium hydroxide and ammonia; triethylamine, Organic bases such as pyridine; metal alkoxides such as triisopropoxyaluminum and tetrabutoxyzirconium; metal chelate compounds having a central metal such as Zr, Ti or Al, etc., but stable production of inorganic fine particle dispersions In the present invention, acid catalysts (inorganic acids, organic acids) and / or metal chelate compounds are preferably used from the viewpoints of properties and storage stability. Of these, hydrochloric acid and sulfuric acid are preferred for inorganic acids, and organic acids preferably have an acid dissociation constant {pKa value (25 ° C.)} of 4.5 or less in water, and further include acids in hydrochloric acid, sulfuric acid and water. An organic acid having a dissociation constant of 3.0 or less is preferable, particularly an organic acid having an acid dissociation constant of 2.5 or less in hydrochloric acid, sulfuric acid or water, and an organic acid having an acid dissociation constant of 2.5 or less in water. More specifically, methanesulfonic acid, oxalic acid, phthalic acid, and malonic acid are more preferable, and oxalic acid is particularly preferable. As a metal chelate compound, the following general formula described later in (metal chelate compound):
Zr (OR ⁰¹ ) _{p 1} (R ⁰² COCHCOR ⁰³ ) _{p 2} ,
Ti (OR ⁰¹ ) _q1 (R ⁰² COCHCOR ⁰³ ) _q2 and Al (OR ⁰¹ ) _r1 (R ⁰² COCHCOR ⁰³ ) _r2
Those selected from the group of compounds represented by In the present invention, it is preferable that a β-diketone compound and / or a β-ketoester compound is further added to the composition for forming a low refractive index layer. Specific examples of β-diketone compounds and / or β-ketoester compounds include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate -Sec-butyl, acetoacetate-t-butyl, 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane- Examples include dione and 5-methyl-hexane-dione. Of these, ethyl acetoacetate and acetylacetone are preferred, and acetylacetone is particularly preferred. These β-diketone compounds and / or β-ketoester compounds may be used alone or in combination of two or more. In the present invention, the β-diketone compound and / or β-ketoester compound is preferably used in an amount of 2 mol or more, more preferably 3 to 20 mol, per 1 mol of the metal chelate compound. From the viewpoint of storage stability of the resulting composition, the amount used for the metal chelate compound of the β-diketone compound and / or β-ketoester compound is preferably within the above range.
The hydrolyzate and / or partial condensate of the organosilane compound is usually obtained in the form of a sol.

  The amount of the organosilane sol component used in the low refractive index layer relative to the functional fluorine-containing polymer is preferably 5 to 100% by mass, more preferably 5 to 40% by mass, still more preferably 8 to 35% by mass, 30% by mass is particularly preferred. If the amount used is less than or equal to the upper limit, problems such as excessive increase in the refractive index or deterioration of the shape / surface shape of the film do not occur. Therefore, it is preferable to use an appropriate amount within this range.

(Polyfunctional polymerizable compound)
As described above, a polyfunctional polymerizable compound can be further added to the curable composition for forming the low refractive index layer.

  As a polyfunctional polymerizable compound, any of radical polymerizable functional groups and / or cationic polymerizable functional groups may contain two or more polymerizable groups. Examples of the radical polymerizable functional group include an ethylenically unsaturated group such as a (meth) acryloyl group, a vinyloxy group, a styryl group, and an allyl group, and 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 having a radical polymerizable group is preferably selected from compounds having at least two terminal ethylenically unsaturated bonds. Preferred 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. What was demonstrated by (A-ha) mentioned above in the term of the (matrix of a high refractive index layer) can be used preferably. These can have chemical forms such as monomers, prepolymers, ie dimers, trimers and oligomers, or mixtures thereof and copolymers thereof.

  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, a vinyl hydrocarbon compound, and a vinyl ether compound. In the present invention, one or more of the above cationic 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. Specific contents of these radical polymerizable compounds and cationic polymerizable compounds include those similar to the polyfunctional monomers and oligomers described in the high refractive index layer.

  The radical polymerizable compound and the cationic polymerizable compound described above are preferably contained in a mass ratio of radical polymerizable compound: cation polymerizable compound in a ratio of 90:10 to 20:80, and 80:20 to More preferably, it is contained at a ratio of 30:70. Moreover, it is preferable that the compounding quantity of the said polyfunctional polymerizable compound containing a radically polymerizable compound and a cationically polymerizable compound shall be 0.1-20 mass parts with respect to 100 mass parts of said fluoropolymers.

(Fine particles of inorganic compounds)
Next, the fine particles of an inorganic compound that may be contained in the low refractive index layer of the present invention (hereinafter sometimes simply referred to as inorganic fine particles) are described below.

  The average particle size of the inorganic fine particles is preferably 5 to 100 nm, more preferably 10 to 90 nm, and still more preferably 15 to 85 nm. Moreover, it is preferable to contain 5-80 mass% of inorganic fine particles in a low refractive index layer, More preferably, it is 10-70 mass%, More preferably, it is 15-65 mass%. If the content of the inorganic fine particles is equal to or higher than the lower limit, the scratch resistance can be effectively improved. Therefore, the content of the inorganic fine particles is preferably within this range.

  The inorganic fine particles contained in the low refractive index layer desirably have a low refractive index. Examples of such inorganic fine particles include magnesium fluoride and silica fine particles. In particular, silica fine particles are preferably used from the viewpoint of refractive index, dispersion stability, and cost. The silica fine particles may be either crystalline or amorphous, and may be monodispersed particles or aggregated particles as long as a predetermined particle size is satisfied. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite. Here, the average particle diameter of the inorganic fine particles is measured by a Coulter counter.

In order to further reduce the increase in the refractive index of the low refractive index layer, it is preferable to use hollow silica fine particles (hereinafter sometimes referred to as hollow particles) as the inorganic fine particles. The hollow particles preferably have a refractive index of 1.17 to 1.40, more preferably 1.17 to 1.35, and particularly preferably 1.17 to 1.30. The refractive index here represents the refractive index of the entire particle, and does not represent the refractive index of only the silica component of the outer shell forming the hollow particles. The refractive index of the hollow particles is preferably 1.17 or more from the viewpoint of the strength of the particles and the scratch resistance of the low refractive index layer containing the hollow particles.
The refractive index of these hollow particles can be measured with an Abbe refractometer [manufactured by Atago Co., Ltd.].

The void ratio w (%) of the hollow particles is calculated according to the following formula (5), where r _{i is} the radius of the cavity in the hollow particles and r _o is the radius of the particle outer shell.
Equation (5): w = (4πr i 3/3) / (4πr o 3/3) × 100
= (R _i / r _o ) ³ × 100
The porosity of the hollow particles is preferably 10 to 60%, more preferably 20 to 60%, and most preferably 30 to 60%.

  Inorganic fine particles are treated with physical surface treatment such as plasma discharge treatment or corona discharge treatment in order to stabilize the dispersion in the dispersion or coating solution, or to improve the affinity and binding properties with the binder component. Chemical surface treatment with a surfactant, a coupling agent, or the like may be performed.

As the coupling agent, an alkoxy metal compound (for example, a titanium coupling agent or a silane coupling agent) is preferably used. Of these, silane coupling treatment is particularly effective, and among them, a hydrolyzate of organosilane represented by the general formula (1) and / or a partial condensate thereof is particularly preferably used.
Among these, a silane coupling agent containing a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group, an alkoxysilyl group, an acyloxy group, or an acylamino group is preferable, and an epoxy group or a polymerizable acyloxy group is particularly preferable. It is a silane coupling agent containing a group ((meth) acryloyl) and a polymerizable acylamino group (acrylamino, methacrylamino).

The above-mentioned coupling agent is used as a surface treatment agent for the inorganic fine particles of the low refractive index layer in order to perform surface treatment in advance before preparing the coating solution for the composition for forming the low refractive index layer. It is preferable to use it as an additive to the functional fluorine-containing polymer at the time of liquid preparation.
The coupling agent is preferably added in an amount of 0.5 to 100% by mass, more preferably 1 to 75% by mass, more preferably 5 to 45% by mass, based on the inorganic fine particles. is there. Within this range, the inorganic fine particles do not aggregate in the low refractive index layer, which is preferable.
The inorganic fine particles are preferably dispersed in the medium in advance before the surface treatment in order to reduce the load of the surface treatment.

(Catalyst for improving dispersibility)
In the present invention, the treatment for improving the dispersibility of the inorganic fine particles used in the low refractive index layer by the hydrolyzate of organosilane and / or the condensation reaction product 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, methanesulfonic acid and toluenesulfonic acid; inorganic bases such as sodium hydroxide, potassium hydroxide and ammonia; triethylamine and pyridine Organic bases such as: metal alkoxides such as triisopropoxyaluminum and tetrabutoxyzirconium; metal chelate compounds having a central metal such as Zr, Ti or Al, etc., but the production stability of inorganic fine particle dispersions In view of storage stability, acid catalysts (inorganic acids and organic acids) and / or metal chelate compounds are preferably used in the present invention. For inorganic acids, hydrochloric acid and sulfuric acid, and for organic acids, the acid dissociation constant in water {pKa value (25 ° C.)} is preferably 4.5 or less, and the acid dissociation constant in hydrochloric acid, sulfuric acid, or water is 3.0 or less. More preferred is an organic acid having an acid dissociation constant of 2.5 or less in hydrochloric acid, sulfuric acid or water, still more preferred is an organic acid having an acid dissociation constant of 2.5 or less in water, and methanesulfone. Acid, oxalic acid, phthalic acid and malonic acid are particularly preferred, and oxalic acid is most preferred.

When the hydrolyzable group of organosilane is an alkoxy group and the acid catalyst is an organic acid, the amount of water added can be reduced because the carboxyl group or sulfo group of the organic acid supplies protons. In this case, the amount of water added is usually 0 to 2 mol, preferably 0 to 1.5 mol, more preferably 0 to 1 mol, and particularly preferably 0 to 0.5 mol. is there. When alcohol is used as the solvent, it is also preferred that substantially no water is added.

  When the acid catalyst is an inorganic acid, the acid catalyst is used in an amount of 0.01 to 10 mol%, preferably 0.1 to 5 mol%, based on the hydrolyzable group. In this case, the optimum amount of use varies depending on the amount of water added, but when water is added, it is 0.01 to 10 mol%, preferably 0.1 to 5 mol% based on the hydrolyzable group. In the case where water is not substantially added, it is 1 to 500 mol%, preferably 10 to 200 mol%, more preferably 20 to 200 mol%, still more preferably 50%, based on the hydrolyzable group. It is -150 mol%, Most preferably, it is 50-120 mol%.

  Although a process is performed by stirring at 15-100 degreeC, it is preferable to adjust with the reactivity of organosilane.

(Metal chelate compound)
In the present invention, the metal chelate compound used as a catalyst for improving the dispersibility by the hydrolyzate and / or condensation reaction product of organosilane in the form of inorganic fine particles has a general formula R ⁰¹ OH (wherein R ⁰¹ is 1 to 1 carbon atoms). And / or the general formula R ⁰² COCH ₂ COR ⁰³ (wherein R ⁰² is an alkyl group having 1 to 10 carbon atoms, and R ⁰³ is an alkyl group having 1 to 10 carbon atoms). An alkyl group or an alkoxy group having 1 to 10 carbon atoms.) If a compound selected from Zr, Ti and Al with a compound represented by (1) as a ligand is used as a central metal, it is particularly suitable without limitation. Can be used. Within this category, two or more metal chelate compounds may be used in combination.

The metal chelate compound used in the present invention preferably has the following general formula:
Zr (OR ⁰¹ ) _{p 1} (R ⁰² COCHCOR ⁰³ ) _{p 2} ,
Ti (OR ⁰¹ ) _q1 (R ⁰² COCHCOR ⁰³ ) _q2 and Al (OR ⁰¹ ) _r1 (R ⁰² COCHCOR ⁰³ ) _r2
Are preferably selected from the group of compounds represented by the formula (I), which serve to promote the condensation reaction of the organosilane compound.

R ⁰¹ and R ⁰² in the metal chelate compound may be the same or different, and an alkyl group having 1 to 10 carbon atoms, specifically, an ethyl group, an n-propyl group, an i-propyl group, or n-butyl. Group, s-butyl group, t-butyl group, n-pentyl group; or an aryl group having 6 to 10 carbon atoms, specifically, a phenyl group. R ⁰³ is an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms as in R ⁰¹ and R ⁰² , as well as an alkoxy group having 1 to 10 carbon atoms, such as a methoxy group, an ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, s-butoxy group, t-butoxy group and the like. Moreover, p1, p2, q1, q2, r1, and r2 in a metal chelate compound represent the integer determined so that it may become a 4 or 6-coordinate.

Specific examples of these metal chelate compounds include tri-n-butoxyethylacetoacetate zirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate) zirconium, tetrakis (n-propylacetate). Zirconium chelate compounds such as acetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium; diisopropoxy bis (ethylacetoacetate) titanium, diisopropoxy bis (acetylacetate) titanium, diiso Titanium chelate compounds such as propoxy bis (acetylacetone) titanium; diisopropoxyethyl acetoacetate aluminum, diisopropyl Poxyacetylacetonate aluminum, isopropoxybis (ethylacetoacetate) aluminum, isopropoxybis (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonate) aluminum, monoacetylacetonate bis (ethyl) An aluminum chelate compound such as acetoacetate) aluminum.

  Among these metal chelate compounds, tri-n-butoxyethyl acetoacetate zirconium, diisopropoxy bis (acetylacetonate) titanium, diisopropoxyethyl acetoacetate aluminum, and tris (ethyl acetoacetate) aluminum are preferable. . These metal chelate compounds can be used individually by 1 type or in mixture of 2 or more types. Moreover, the partial hydrolyzate of these metal chelate compounds can also be used.

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

(Other additives)
In addition to the components described above, the low refractive index layer in the present invention is provided with an anti-fouling property of a known silicone compound or fluorine compound for the purpose of imparting antifouling properties, water resistance, chemical resistance, slipping properties and the like. It is preferable that a soiling agent, a slipping agent and the like are appropriately added. When these additives are added, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the curable composition for forming the low refractive index layer, more preferably 0.05 to 10%. It is a case where it is added in the range of mass%, particularly preferably 0.1 to 5 mass%.

  Preferable examples of the silicone compound include those having a substituent at the end of the compound chain and / or the side chain, containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, fluoroalkyl group, polyoxyalkylene group, carboxyl group, amino group, etc. Groups.

  Although there is no restriction | limiting in particular in the molecular weight of a silicone type compound, It is preferable that it is 100,000 or less, It is especially preferable that it is 50,000 or less, It is most preferable that it is 3000-30000. Although there is no restriction | limiting in particular also in silicone atom content of a silicone type compound, It is preferable that it is 18.0 mass% or more, It is especially preferable that it is 25.0-37.8 mass%, 30.0-37. Most preferably, it is 0.0 mass%.

  Examples of preferable silicone compounds include X-22-174DX, X-22-2426, X-22-164B, X22-164C, X-22-170DX, X-22-176D, X, manufactured by Shin-Etsu Chemical Co., Ltd. -22-1821 (named above), Chisso Corporation, FM-0725, FM-7725, FM-4421, FM-5521, FM6621, FM-1121, Gelest DMS-U22, RMS-033, RMS- Examples include, but are not limited to, 083, UMS-182, DMS-H21, DMS-H31, HMS-301, FMS121, FMS123, FMS131, FMS141, and FMS221 (named above).

As the fluorine compound, a compound having a fluoroalkyl group is preferable. The fluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and a straight chain [eg, —CF ₂ CF ₃ , —CH ₂ (CF ₂ ) ₄ H, —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ H, etc.], even branched structures [eg, —CH (CF ₃ ) ₂ , —CH ₂ CF (CF ₃ ) ₂ , —CH (CH ₃ ) CF ₂ CF ₃ , —CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.], an alicyclic structure (preferably a 5- or 6-membered ring such as a perfluorocyclohexyl group). , A perfluorocyclopentyl group or an alkyl group substituted with these, and may have an ether bond (for example, —CH ₂ OCH ₂ CF ₂ CF ₃ , —CH ₂ CH ₂ OCH ₂ C). ₄ F ₈ H, —CH ₂ CH ₂ OCH ₂ CH ₂ C ₈ F ₁₇ , —CH ₂ CH ₂ OCF ₂ CF ₂ OCF ₂ CF ₂ H, etc.). A plurality of the fluoroalkyl groups may be contained in the same molecule.

  It is preferable that the fluorine-based compound further has a substituent that contributes to bond formation or compatibility with the film of the low refractive index layer. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, polyoxyalkylene group, carboxyl group, amino group and the like.

  The fluorine-based compound may be a polymer or an oligomer with a compound not containing a fluorine atom, and the molecular weight is not particularly limited and is used. Although there is no restriction | limiting in particular in fluorine atom content of a fluorine-type compound, It is preferable that it is 20 mass% or more, It is especially preferable that it is 30-70 mass%, It is most preferable that it is 40-70 mass%. Examples of preferred fluorine-based compounds include “R-2020”, “M-2020”, “R-3833”, “M-3833” {above, Daikin Chemical Industries, Ltd.}; ”,“ Megafuck F-172 ”,“ Megafuck F-179A ”,“ Defenser MCF-300 ”{manufactured by Dainippon Ink, Inc.}, and the like, but are not limited thereto.

  For the purpose of imparting properties such as dust resistance and antistatic properties, a dustproof agent, antistatic agent, etc., such as known cationic surfactants or polyoxyalkylene compounds, may be added as appropriate. These dustproofing agent and antistatic agent may contain the structural unit as a part of the function in the above-mentioned silicone compound or fluorine compound. When these are added as additives, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the composition for forming a low refractive index layer, more preferably 0.05 to 10% by mass. It is a case where it is added in a range, particularly preferably 0.1 to 5% by mass. Examples of preferable compounds include “Megafac F-150” (manufactured by Dainippon Ink Co., Ltd.), “SH-3748” (manufactured by Toray Dow Corning Co., Ltd.), and the like, but are not limited thereto.

  The low refractive index layer may also contain microvoids. Specific examples include the contents described in JP-A-9-222502, JP-A-9-288201, JP-A-11-6902, and the like.

  Furthermore, in the present invention, organic fine particles can also be used. Examples of the organic fine particles include compounds described in paragraphs [0020] to [0038] of JP-A No. 11-3820, and the shape thereof. Is the same as the above-mentioned inorganic fine particles.

  The thickness of the low refractive index layer is preferably 30 to 200 nm, more preferably 50 to 150 nm, and particularly preferably 70 to 100 nm.

[Properties of low refractive index layer]
The low refractive index layer in the present invention preferably has a surface energy of 26 mN / m or less, more preferably 15 to 25.8 mN / m. It is preferable from the viewpoint of antifouling property to make the surface energy within this range.

The surface energy of a solid can be determined by a contact angle method, a wet heat method, and an adsorption method as described in “Basics and Applications of Wetting” (issued by Realize 1989.12.10). In the case of the antireflection film of the present invention, it is preferable to use a contact angle method. Specifically, two kinds of solutions whose surface energy is known are dropped on the surface of the antireflection film provided as a transparent protective film on the polarizing plate, and at the intersection of the surface of the droplet and the film surface, The angle formed between the tangent line drawn on the droplet and the film surface is defined as the contact angle, and the surface energy of the film can be calculated by calculation. The contact angle of the outermost layer surface with water is preferably 90 ° or more, more preferably 95 ° or more, and particularly preferably 100 ° or more.

  The dynamic friction coefficient on the surface of the low refractive index layer is preferably 0.25 or less, more preferably 0.05 to 0.25, and particularly preferably 0.03 to 0.15. The dynamic friction coefficient described here refers to a dynamic friction coefficient between a surface and a stainless steel hard sphere having a diameter of 5 mm when a load of 0.98 N is applied to a stainless steel hard sphere having a diameter of 5 mm and the surface is moved at a speed of 60 cm / min. .

  The haze of the low refractive index layer is preferably 3% or less, more preferably 2% or less, and most preferably 1% or less. The hardness 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 K-5400. The scratch resistance of the low refractive index layer is preferably as the wear amount in the Taber test according to JIS K-6902 is smaller.

[Formation of low refractive index layer]
The low refractive index layer is a coating composition in which a functional fluorine-containing polymer, an organosilane compound, a polyfunctional polymerizable compound, fine particles of an inorganic compound, a metal chelate compound, and other optional components contained as desired are dissolved or dispersed. It is preferably formed by light irradiation, electron beam irradiation or a crosslinking reaction by heating, or a polymerization reaction at the same time or after application.

  In particular, when the low refractive index layer is formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound, the crosslinking reaction or the polymerization reaction is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less. By forming in an atmosphere having an oxygen concentration of 10% by volume or less, an outermost layer having excellent physical strength and chemical resistance can be obtained. The oxygen concentration is preferably 6% by volume or less, more preferably 4% by volume or less, particularly preferably 2% by volume or less, and most preferably 1% by volume or less.

  As a method of reducing the oxygen concentration to 10% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.

  A metal oxide thin film layer can also be used for the low refractive index layer. Silicon dioxide or magnesium fluoride is preferred, and silicon dioxide is more preferred. The layer thickness of the metal oxide thin film layer is controlled in the range of 50 to 120 nm. By setting it within this range, the average value of the specular reflectance of the antireflection film can be suppressed to 3% or less, and the formula (1) can be satisfied.

  The metal thin film layer and the metal oxide thin film layer can be formed by sputtering, vacuum deposition, ion plating, plasma CVD, plasma PVD, or coating of ultrafine particles of metal or metal oxide. Sputtering, vacuum deposition, and ion plating are preferable, and sputtering is particularly preferable.

  As a method for forming the metal thin film layer by a sputtering method, a DC magnetron sputtering method using a metal target, an RF magnetron sputtering method, or the like can be used.

As a method of forming a metal oxide thin film layer by a sputtering method, a metal target is used, a DC magnetron sputtering method, an RF magnetron sputtering method, an AC magnetron sputtering method, or an RF using a metal oxide target. Although there is a method using a magnetron sputtering method, it is preferable to use AC magnetron sputtering and control the flow rate of oxygen by a plasma emission monitor method in view of film formation speed and discharge stability. .

As described above, the antireflection film of the present invention preferably suppresses aggregation of inorganic fine particles contained in the low refractive index layer in order to improve whiteness, and further, the outermost surface on the antireflection film forming side of the antireflection film It is preferable for improving the whiteness to have a specific shape. The surface shape is made specific by (a) containing specific inorganic fine particles in the low refractive index layer, surface-treating the inorganic fine particles, and (b) controlling the drying rate (described later). be able to.
In an embodiment in which the antireflection film of the present invention is formed by coating a low refractive index layer on a high refractive index layer, the surface of the high refractive index layer is formed as described above in the section of [High refractive index layer]. It is preferable to have a specific surface irregularity form, and as described above in (Ultrafine particles of high refractive index fine particles), high refractive index fine particles within a specific size range may be contained in the high refractive index layer. Preferably, the low refractive index layer is applied on the high refractive index layer. By applying on the high refractive index layer, the low refractive index layer can be applied more uniformly, which can contribute to the improvement of whiteness.

[Overcoat layer]
In the antireflection film of the present invention, an overcoat layer further comprising at least one compound selected from a fluorine-containing compound, a silicon-containing compound, and a long-chain alkyl group-containing compound having 4 or more carbon atoms on the low refractive index layer. It is preferable to be laminated.

  As the fluorine-containing compound used for the overcoat layer, fluorine-containing surfactants, fluorine-containing polymers, fluorine-containing ethers and fluorine-containing silane compounds are preferably used.

  As the fluorine-containing surfactant, the hydrophilic part may be any of anionic, cationic, nonionic and amphoteric. In the fluorine-containing surfactant, part or all of the hydrocarbon hydrogen atoms constituting the hydrophobic portion are substituted with fluorine atoms.

  The fluorine-containing polymer is preferably synthesized by a polymerization reaction of an ethylenically unsaturated monomer (fluorine-containing monomer) containing a fluorine atom. Examples of fluorine-containing monomers include fluoroolefins (eg, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole), fluorine substitution Included are esters of alcohols with acrylic acid or methacrylic acid and fluorinated vinyl ethers.

  As the fluorine-containing polymer for the overcoat layer, a copolymer obtained from two or more kinds of fluorine-containing monomers may be used. A copolymer of a fluorine-containing monomer and a monomer not containing a fluorine atom may be used. Examples of monomers that do not contain fluorine atoms include olefins (eg, ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride), acrylic esters (eg, methyl acrylate, methyl acrylate, ethyl acrylate, acrylic acid 2- Ethyl hexyl), methacrylic acid esters (for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate), styrene and its derivatives (for example, styrene, divinylbenzene, vinyltoluene, α-methylstyrene), vinyl ether ( For example, methyl vinyl ether), vinyl esters (eg, vinyl acetate, vinyl propionate, vinyl cinnamate), acrylamide (eg, Nt-butylacrylamide, N-cyclohexylacrylamide) , Methacrylamide, acrylonitrile and derivatives thereof.

  In order to impart slipperiness to the overcoat layer, a repeating unit composed of polyorganosiloxane may be introduced into the fluorine-containing polymer. The fluorine-containing polymer having a repeating unit composed of polyorganosiloxane can be obtained, for example, by polymerization of a polyorganosiloxane having a reactive group at the terminal and a fluorine-containing monomer. The reactive group is formed by chemically bonding an ethylenically unsaturated monomer (eg, acrylic acid and its ester, methacrylic acid and its ester, vinyl ether, styrene and derivatives) to the end of the polyorganosiloxane.

  As the fluorine-containing polymer, commercially available fluorine-containing polymers such as “Cytop”, “Lumiflon” {manufactured by Asahi Glass Co., Ltd.}, “Teflon (registered trademark) AF” (manufactured by DuPont), “OPSTAR” {JSR May be used.

The fluorine-containing ether is a compound generally used as a lubricant. Examples of the fluorinated ether include perfluoropolyether and derivatives thereof.
Examples of the fluorine-containing silane compound include a silane compound containing a perfluoroalkyl group (eg, heptadecafluoro-1,2,2,2-tetradecyl) triethoxysilane). Commercially available fluorine-containing silane compounds such as “KBM-7803” and “KP-801M” {manufactured by Shin-Etsu Chemical Co., Ltd.} may also be used.

  The fluorine-containing compound used for the overcoat layer preferably contains fluorine atoms in the range of 30 to 80% by mass, and more preferably in the range of 40 to 75% by mass.

  It is particularly preferable to use a fluorine-containing polymer for the overcoat layer. The fluorine-containing polymer is preferably further crosslinked. Specifically, a crosslinkable group is introduced into the fluorine-containing polymer, or the fluorine-containing polymer is crosslinked using a crosslinking agent. The crosslinkable group is preferably introduced as a side chain into the fluorine-containing polymer. By copolymerizing a monomer having a crosslinkable group during the synthesis of the fluoropolymer, the crosslinkable group can be introduced into the fluoropolymer as a side chain. Moreover, a fluorine-containing polymer can be bridge | crosslinked by making the compound (crosslinking agent) which has a 2 or more crosslinkable group react with the side chain of a fluorine-containing polymer. The crosslinkable group is preferably a functional group that reacts upon irradiation with radiation such as light (preferably ultraviolet rays) or electron beam (EB), or by heating to crosslink the fluoropolymer. A functional group that is cross-linked by irradiation with radiation is more preferable, and a functional group that is cross-linked by irradiation with ultraviolet light is most preferable. That is, when the treatment temperature for the crosslinking reaction is low, the flatness of the support is hardly deteriorated, and the heating line in the production process can be shortened. Further, there is an advantage that irradiation with ultraviolet rays can be performed with relatively inexpensive equipment.

  Examples of crosslinkable groups include acryloyl, methacryloyl, allyl, isocyanate, epoxy, alkoxysilyl, aziridine, oxazoline, aldehyde, carbonyl, hydrazine, carboxyl, methylol and activity A methylene group is included. The thickness of the overcoat layer is preferably 2 to 50 nm, more preferably 5 to 30 nm, and most preferably 5 to 20 nm.

[Hard coat layer]
The hard coat layer can be 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 (or medium refractive index layer).

The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. For example, it can be formed by coating a coating composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer on a transparent support and subjecting the polyfunctional monomer or polyfunctional oligomer to a crosslinking reaction or a polymerization reaction. .

  The functional group of the ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable. Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable.

  Specific examples of the photopolymerizable polyfunctional monomer having a photopolymerizable functional group include those exemplified for the high refractive index layer, and it is preferable to perform polymerization using a photopolymerization initiator and a photosensitizer. The photopolymerization reaction is preferably performed by ultraviolet irradiation after the hard coat layer is applied and dried.

  An oligomer and / or polymer having a mass average molecular weight of 500 or more may be added to the hard coat layer in order to impart brittleness. Examples of the oligomer and polymer include (meth) acrylate-based, cellulose-based, and styrene-based polymers, urethane acrylate, and polyester acrylate. Preferable examples include polyglycidyl (meth) acrylate and polyallyl (meth) acrylate) having a functional group in the side chain.

  The content of the oligomer and / or polymer in the hard coat layer is preferably 5 to 80% by mass, more preferably 25 to 70% by mass, and particularly preferably 35 to 65% by mass with respect to the total mass of the hard coat layer. It is.

The hardness of the hard coat 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, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.

  When the hard coat layer is formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound, the crosslinking reaction or the polymerization reaction is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less. By forming in an atmosphere having an oxygen concentration of 10% by volume or less, a hard coat layer excellent in physical strength and chemical resistance can be formed. Preferably, it is formed by a crosslinking reaction or polymerization reaction of an ionizing radiation curable compound in an atmosphere having an oxygen concentration of 6% by volume or less, more preferably an oxygen concentration of 4% by volume or less, particularly preferably an oxygen concentration of 2 Volume% or less, most preferably 1 volume% or less.

  As a method of reducing the oxygen concentration to 10% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.

  The hard coat layer is preferably constructed by applying a coating composition for forming a hard coat layer on the surface of the transparent support.

  The coating solvent is preferably a ketone solvent exemplified in the high refractive index layer. By using the ketone solvent, the adhesion between the surface of the transparent support (particularly, triacetyl cellulose support) and the hard coat layer is further improved. Particularly preferred coating solvents are methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. The coating solvent may contain a solvent other than the ketone solvent exemplified for the high refractive index layer. The coating solvent preferably contains a ketone solvent in an amount of 10% by mass or more of the total solvent contained in the coating composition. The content of the ketone solvent is more preferably 30% by mass or more, and still more preferably 60% by mass or more.

(Other additives)
For the hard coat layer, an additive such as a coupling agent, a leveling agent, a thixotropy agent, an antistatic agent, and at least one of inorganic and organic particles can be used.

[Other layers of antireflection film]
In addition to the above-described layers, the antireflection film may be provided with layers other than these layers as necessary. For example, an adhesive layer, a shield layer, a sliding layer, or an antistatic layer may be provided. The shield layer is provided to shield electromagnetic waves and infrared rays.

[Production method of antireflection film]
Each layer of the antireflection film can be formed by a coating method such as a wire bar coating method, a gravure coating method, a micro gravure method, or a die coating method. From the viewpoint of minimizing the wet coating amount and eliminating drying unevenness, the microgravure method and the gravure method are preferable.

  Production of at least two layers of the plurality of optical thin films of the antireflection film of the present invention is performed by a process consisting of feeding the support film once, forming each optical thin film and winding the film. From the viewpoint of cost, when the antireflection film has a three-layer structure, it is more preferable to form three layers in one step. In such a manufacturing method, a plurality of sets of coating stations and drying / curing zones, preferably the same number or more as the number of optical thin films, are provided in tandem between the feeding and winding of the support film of the coating machine. Is achieved.

  FIG. 2 shows an example of the device configuration. FIG. 2 shows a first coating station (102), a first drying zone (103), and a first UV irradiator (104) during one step from roll film delivery (101) to winding (112). , Second coating station (105), second drying zone (106), second UV irradiator (107), third coating station (108), third drying zone (109), third This is an example including a UV irradiator (110) and a post-drying zone (111), for example, a medium refractive index layer, a high refractive index layer, a low refractive index layer, a hard coat layer, a high refractive index layer, a low refractive index. Up to three functional layers can be formed in one step, such as three layers of rate layers. If necessary, as a device configuration with the number of coating stations reduced to two, only two layers of medium refractive index layer and high refractive index layer are formed in one step, and the results of checking the surface condition, film thickness, etc. As a device configuration that improves the yield by feedback or increases the number of coating stations to four, the hard coat layer, medium refractive index layer, high refractive index layer, and low refractive index layer are formed and applied in one step. Another preferred mode is to make the manufacturing method such as significantly reducing the cost.

[Drying speed]
In the production of the antireflection film of the present invention, it is preferable to control the drying rate in the drying step of the coating film, and in particular, it is preferable to control the drying rate in the drying step in the low refractive index layer forming step. . Specifically, the drying rate is preferably 0.10 to 1.5 g / m ² · sec. More preferably, it is 0.12-1.5 g / m < ² > / second, More preferably, it is 0.15-1.0 g / m < ² > / ^second . If the drying speed is equal to or less than the upper limit value, it is preferable because problems such as uneven drying and brushing due to latent heat of evaporation do not occur. Further, if the drying speed is equal to or higher than the lower limit value, the aggregation of inorganic fine particles in the coating film occurs, resulting in fine irregularities on the film surface, thereby increasing the scattering of light on the surface and giving it whiteness. This is preferable because defects such as visibility and display quality are easily lost. Therefore, by setting the drying speed within this range, a desired surface shape having no unevenness can be formed on the entire surface of the cured film, and the dispersion of the inorganic fine particles in the cured film can be sufficiently maintained.

The method for obtaining the drying rate is as follows.
The solvent in the coating solution is evaporated in advance, and the solvent composition ratio with respect to the solid content concentration is obtained by gas chromatography. The coated material is sampled at an arbitrary time after coating, and the evaporation rate is obtained from the solid content concentration at that time.
The drying speed can be controlled by the concentration of the coating film material and coating solution, the drying temperature, the amount of drying air, and the like.

<Protective film for polarizing plate>
In producing the polarizing plate of the present invention, in order to use the antireflection film as the surface protective film of the polarizing film (protective film for polarizing plate), the surface of the transparent support opposite to the side having the antireflection film, that is, It is preferable to improve the adhesion with a polarizing film containing polyvinyl alcohol as a main component by hydrophilizing the surface to be bonded to the polarizing film.

  When using an antireflection film as the polarizing plate protective film, it is particularly preferable to use a triacetyl cellulose film as the transparent support of the antireflection film.

  As a method for producing a protective film for polarizing plate in the present invention, (1) each of the above layers (for example, a high refractive index layer, a hard coat layer, an outermost layer, etc.) is provided on one surface of a transparent support previously saponified. (2) After coating each of the above layers (for example, a high refractive index layer, a hard coat layer, a low refractive index layer, an outermost layer, etc.) on one surface of the transparent support, it is pasted on the polarizing film. There are two methods of saponifying the mating side. From the viewpoint of ensuring adhesion between the support and the layer coated thereon, for example, the hard coat layer, the surface to which the hard coat layer is coated is hydrophilic. It is preferable to adopt the method (2) that is not changed.

[Saponification]
(1) Immersion method An antireflection film is immersed in an alkaline solution under appropriate conditions to saponify all surfaces that are reactive with alkali on the entire surface of the film, requiring special equipment. This is preferable from the viewpoint of cost. The alkaline liquid is preferably a sodium hydroxide aqueous solution. A preferred concentration is 0.5 to 3 mol / L, particularly preferably 1 to 2 mol / L. The liquid temperature of a preferable alkali liquid is 30-70 degreeC, Most preferably, it is 40-60 degreeC.

  The combination of the above saponification conditions is preferably a combination of relatively mild conditions, but can be set according to the material and configuration of the antireflection film and the target contact angle. After being immersed in the alkaline solution, it is preferable to sufficiently wash with water or neutralize the alkaline component by immersing in a dilute acid so that the alkaline component does not remain in the film.

  By saponification treatment, the surface of the transparent support opposite to the surface having the antireflection layer is hydrophilized. The protective film for polarizing plate is used by adhering the hydrophilic surface of the transparent support to the polarizing film. The hydrophilized surface is effective for improving the adhesiveness with the adhesive layer mainly composed of polyvinyl alcohol.

In the saponification treatment, the lower the contact angle with water on the surface of the transparent support opposite to the side having the antireflection film, the better from the viewpoint of adhesion to the polarizing film. Since the surface on the side having the film may be damaged by alkali, it is important to set the reaction conditions to the minimum necessary. As an index of damage to the antireflection film caused by alkali, the contact angle with water of the surface of the transparent support opposite to the side having the antireflection film, that is, the bonding surface of the antireflection film with the polarizing film was used. In this case, particularly when the support is triacetylcellulose, the contact angle is preferably 20 ° to 50 °, preferably 30 ° to 50 °, more preferably 40 ° to 50 °. If it is 50 degrees or less, adhesiveness with a polarizing film is favorable and preferable. On the other hand, if it is 20 ° or more, the damage received by the antireflection film does not become excessively large, and physical strength, light resistance, etc. are not impaired.

(2) Alkaline solution coating method As a means for avoiding damage to the antireflection film in the above-mentioned immersion method, an alkali solution is applied only on the surface opposite to the surface having the antireflection film, heated, and washed under appropriate conditions. A drying alkali solution coating method is preferably used. The application in this case means that an alkali solution or the like is brought into contact only with the surface to be saponified, and at this time, the contact angle with respect to water of the bonded surface of the antireflection film is 10 to 50 °. It is preferable to perform a saponification treatment. Further, in addition to application, it is also included to be performed by spraying, contacting with a belt containing liquid, or the like. By adopting these methods, a separate facility and process for applying an alkaline solution are required. Therefore, from the viewpoint of cost, the immersion method (1) is superior, but only on the surface subjected to saponification treatment. Since the liquid comes into contact, the surface on the opposite side is excellent in that it can have a layer using a material that is weak against alkaline liquid. For example, vapor deposition films and sol-gel films have various effects such as corrosion, dissolution, and peeling due to alkali solution, so it is not desirable to use the immersion method. Is possible.

  In any of the saponification methods (1) and (2) above, since each layer can be formed by unwinding from a roll-shaped support, a series of steps are added in addition to the above-described antireflection film manufacturing process. It can also be performed as an operation. Furthermore, the polarizing plate can be produced more efficiently than the same operation as a single wafer by continuously performing the bonding process with the long polarizing film that has been unwound in the same manner.

<Polarizing plate>
As shown in FIG. 1, the preferable polarizing plate of this invention has the antireflection film of this invention in at least one as a protective film (protective film for polarizing plates) of a polarizing film. In FIG. 1, an antireflection film 11 having an antireflection film 10 comprising an intermediate refractive index layer 3, a high refractive index layer 4, and a low refractive index layer 5 on one surface of a transparent support 1. The surface 10 of the transparent support 1 without 10 is adhered to the polarizing film 7 via an adhesive layer 6 made of polyvinyl alcohol, and the protective film 8 of the other polarizing film is interposed via the adhesive layer 6. The polarizing film 7 is bonded to the main surface opposite to the main surface to which the antireflection film 11 is bonded. The other surface of the protective film 8 has a pressure-sensitive adhesive layer 9 on the surface main surface opposite to the main surface bonded to the polarizing film.

  By using the antireflection film of the present invention as a protective film for a polarizing plate, a polarizing plate having an antireflection function excellent in physical strength and light resistance can be produced, and the cost can be greatly reduced and the display device can be thinned. .

As the protective film 8 for the other polarizing film, any conventionally known protective film for a polarizing plate can be used. The plastic film listed in the section <Transparent support> may be used.
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>
An optical compensation film (retardation film) is used to improve the viewing angle characteristics of a liquid crystal display screen. A known film can be used as the optical compensation film. However, in terms of widening the viewing angle, the optical compensation film has a layer having optical anisotropy composed of a compound having a discotic structural unit, and the discotic compound and the support. An optical compensation film characterized in that the angle formed with the body has local randomness but changes with the distance from the transparent support is preferable. This angle has local randomness, but 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 subjected to saponification treatment, and is preferably performed according to the same saponification treatment as described above.

  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 preferred that the transparent support has an optical anisotropy that complements the optical anisotropy of the optical compensation film.

<Image display device>
A polarizing plate having an antireflection film can be applied to an image display device such as a liquid crystal display device (LCD) or an electroluminescence display (ELD). A polarizing plate having the antireflection film of the present invention as shown in FIG. 1 is used by bonding directly to the glass of a liquid crystal cell of a liquid crystal display device or through another layer.

  The polarizing plate using the antireflection film of the present invention includes twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), optically compensated bend cell (OCB). ) And the like can be preferably used for a transmissive, reflective, or transflective liquid crystal display device.

[TN mode liquid crystal display]
The TN mode liquid crystal cell is most frequently used as a color TFT liquid crystal display device, and many publications are cited. The alignment state in the liquid crystal cell in the TN mode black display is an alignment state in which the rod-like liquid crystalline molecules rise at the center of the cell and the rod-like liquid crystalline molecules lie in the vicinity of the cell substrate.

[OCB mode liquid crystal display]
The OCB mode liquid crystal cell is a bend alignment mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned in a substantially opposite direction (symmetrically) between the upper part and the lower part of the liquid crystal cell. Since the liquid crystal display device using the bend alignment mode liquid crystal cell is aligned symmetrically between the upper part and the lower part of the liquid crystal cell, the devices disclosed in the specifications of US Pat. Nos. 4,583,825 and 5,410,422 are provided. The bend alignment mode liquid crystal cell has a self-optical compensation function. For this reason, this liquid crystal mode is also called an OCB (Optically Compensatory Bend) liquid crystal mode.

  Similarly to the TN mode, the liquid crystal cell in the OCB mode is in a black display, and the alignment state in the liquid crystal cell is such that the rod-like liquid crystal molecules rise in the center of the cell and the rod-like liquid crystal molecules lie in the vicinity of the cell substrate. .

[VA mode liquid crystal display]
In a VA mode liquid crystal cell, rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied.

The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied and horizontally when a voltage is applied (Japanese Patent Laid-Open No. 2).
(2) Liquid crystal cell {"SID97, Digest of Tech. Papers" (Preliminary Proceedings) Vol. 28 (2) 1997) described on page 845}, (3) liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied. Pp. 58-59 (1998)} and (4) SURVAVAL mode liquid crystal cell (presented at “LCD International 98”).

[IPS mode liquid crystal display]
In the IPS mode liquid crystal cell, the liquid crystal molecules are always rotated in a horizontal plane with respect to the substrate, and are aligned so as to have a slight angle with respect to the longitudinal direction of the electrode when no electric field is applied. When an electric field is applied, the liquid crystal molecules change direction in the direction of the electric field. The light transmittance can be changed by arranging the polarizing plates sandwiching the liquid crystal cell at a predetermined angle. As the liquid crystal molecules, nematic liquid crystal having a positive dielectric anisotropy Δε is used. The thickness (gap) of the liquid crystal layer is more than 2.8 μm and less than 4.5 μm. This is because when the retardation Δn · d is more than 0.25 μm and less than 0.32 μm, a transmittance characteristic having almost no wavelength dependency within the visible light range can be obtained. By combining the polarizing plates, the maximum transmittance can be obtained when the liquid crystal molecules are rotated 45 ° from the rubbing direction to the electric field direction. The thickness (gap) of the liquid crystal layer is controlled by polymer beads. Of course, the same gap can be obtained with glass beads, glass fibers, and resin columnar spacers. The liquid crystal molecules are not particularly limited as long as they are nematic liquid crystals. When the value of the dielectric anisotropy Δε is large, the driving voltage can be reduced, and when the refractive index anisotropy Δn is small, the thickness (gap) of the liquid crystal layer can be increased, the liquid crystal sealing time is shortened, and the gap・ The variation can be reduced.

[Other LCD mode]
For the ECB mode and STN mode liquid crystal display devices, the polarizing plate of the present invention can be provided in the same manner as described above.

  When used in a transmissive or transflective liquid crystal display device, it is combined 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.}. By using these, a display device with higher visibility can be obtained.

  Further, by combining with a λ / 4 plate, it can be used as a polarizing plate for reflective liquid crystal or a surface protective plate for organic EL display to reduce the reflected light from the surface and inside.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the scope of the present invention should not be construed as being limited thereto.

Example 1 and Comparative Example 1
[Preparation of antireflection film (AF)]
[Preparation of coating liquid for hard coat layer (HCLL)]
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
750.0 parts by mass of trimethylolpropane triacrylate “TMPTA” {manufactured by Nippon Kayaku Co., Ltd.}, 270.0 parts by mass of poly (glycidyl methacrylate) having a mass average molecular weight of 15000, 730.0 parts by mass of methyl ethyl ketone, 500. 0 parts by mass and 50.0 parts by mass of a photopolymerization initiator “Irgacure 184” {manufactured by Ciba Specialty Chemicals Co., Ltd.} 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 (HCLL) for a hard coat layer.

[Preparation of coating liquid for hard coat layer (HCLL-2)]
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
Pentaerythritol triacrylate “PET-30” {manufactured by Nippon Kayaku Co., Ltd.}, 742 parts by mass, 277 parts by mass of poly (glycidyl methacrylate) having a mass average molecular weight of 15000, silane coupling agent “KBM-5103” {Shin-Etsu Chemical Co., Ltd. 112 parts by mass, 728 parts by mass of methyl ethyl ketone, 503 parts by mass of cyclohexanone, photopolymerization initiator “Irgacure 184” {manufactured by Ciba Specialty Chemicals Co., Ltd.} 51 parts by mass and fluorine-based surface modifier “F” -476 "[Dainippon Ink Co., Ltd.] 1.5 parts by mass was added and stirred. It filtered with the polypropylene filter with the hole diameter of 0.4 micrometer, and prepared the coating liquid (HCLL-2) for hard-coat layers.

[Preparation of coating liquid for hard coat layer (HCLL-3)]
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
Zirconia fine particle-containing hard coat composition liquid “Desolite Z7404” {manufactured by JSR Corporation} 100 parts by mass, UV curable resin “DPHA” {manufactured by Nippon Kayaku Co., Ltd.} 31 parts, silane coupling agent “KBM- 5103 "{manufactured by Shin-Etsu Chemical Co., Ltd.}, 10 parts by mass," KE-P150 "{silica particles having an average particle size of 1.5 µm, manufactured by Nippon Shokubai Co., Ltd., 30% MIBK (methyl isobutyl ketone) dispersion. 8.9 parts by mass, MXS-300 {cross-linked PMMA particles having an average particle diameter of 3 μm, manufactured by Soken Chemicals Co., Ltd., 30% MIBK dispersion, dispersed for 20 minutes at 10,000 rpm in a polytron disperser. Used after dispersion at 10,000 rpm for 20 minutes in a polytron disperser} 3.4 parts by mass, 29 parts by mass of methyl ethyl ketone, and 13 parts by mass of MIBK were added and stirred. It filtered with the polypropylene filter with the hole diameter of 0.4 micrometer, and prepared the coating liquid (HCLL-3) for hard-coat layers.

{Production of titanium dioxide fine particles}
According to Example 3 of JP2003-327430A, the composition of each element is TiO ₂ : Co ₃ O ₄ : Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: Cobalt-containing titanium dioxide fine particles doped with cobalt in titanium dioxide particles were produced in the same manner as in Example 3 of the same publication except that the content was changed to 0.5. The produced titanium dioxide fine particles had a rutile crystal structure, an average primary particle size of 40 nm, and a specific surface area of 44 m ² / g.

{Preparation of Titanium Dioxide Fine Particle Dispersion (TL-1)}
Add 257.1 g of the above titanium dioxide fine particles, 41.1 g of a polymer dispersant (DP-1) having a mass average molecular weight of 45,000 having the following structure, and 701.8 g of cyclohexanone, together with zirconia beads having a particle diameter of 0.1 mm Dispersed by dynomill. Dispersion was carried out at a dispersion temperature of 20 to 30 ° C. for 5 hours. From observation with a transmission electron microscope (TEM), a titanium dioxide dispersion (TL-1) having an average primary particle size of 45 nm with a particle size of 150 nm or more being 0% was prepared.

{Preparation of titanium dioxide fine particle dispersion (TL-2)}
In the preparation of the titanium dioxide fine particle dispersion (TL-1), the titanium dioxide fine particle dispersion (TL-2) was prepared in the same manner as the preparation of the titanium dioxide fine particle dispersion (TL-1) except that the dispersion time was 3 hours. Was prepared.
The obtained titanium dioxide fine particle dispersion (TL-2) has an average primary particle size of 2.5% with a particle diameter of 150 nm or more, and 0.5% of a particle diameter of 200 nm or more from observation with a transmission electron microscope (TEM) photograph. The particle diameter was 65 nm.

[Preparation of Medium Refractive Index Layer Coating Solution (MLL-1)]
2. 99.1 parts by mass of the above titanium dioxide dispersion (TL-1), 68.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate, “DPHA”, a photopolymerization initiator “Irgacure 907”; 6 parts by mass, 1.2 parts by mass of photosensitizer “Kayacure DETX” {manufactured by Nippon Kayaku Co., Ltd.}, 279.6 parts by mass of methyl ethyl ketone and 1049.0 parts by mass of cyclohexanone were added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a medium refractive index layer coating solution (MLL-1).

[Preparation of Medium Refractive Index Layer Coating Solution (MLL-2)]
A medium refractive index layer coating solution (MLL-2) was prepared in the same manner as the medium refractive index layer coating solution (MLL-1) except that the titanium dioxide dispersion (TL-2) was used.

[Preparation of coating solution for high refractive index layer (HLL-1)]
460.0 parts by mass of the above titanium dioxide dispersion (TL-1), 40.0 parts by mass of a mixture “DPHA” (manufactured by Nippon Kayaku Co., Ltd.) of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate, light Polymerization initiator “Irgacure 907” {manufactured by Ciba Specialty Chemicals Co., Ltd.} 3.3 parts by mass, photosensitizer “Kayacure DETX” {manufactured by Nippon Kayaku Co., Ltd.} 1.1 parts by mass, methyl ethyl ketone 526. 2 parts by mass and 459.6 parts by mass of cyclohexanone were added and stirred. 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 (HLL-1).

[Preparation of coating solution for high refractive index layer (HLL-2)]
A high refractive index layer coating solution (HLL-2) was prepared in the same manner as the high refractive index layer coating solution (HLL-1) except that the titanium dioxide dispersion (TL-2) was used.

[Preparation of coating solution for low refractive index layer (LLL)]
{Synthesis of functional fluorine-containing polymer}
In a 100 mL stainless steel autoclave with a stirrer, 40 mL of ethyl acetate, 14.7 g of hydroxyethyl vinyl ether and 0.55 g of dilauroyl peroxide were charged, and the system was degassed and replaced with nitrogen gas. Further, 25 g of hexafluoropropylene (HFP) was introduced into the autoclave and the temperature was raised to 65 ° C. The pressure when the temperature in the autoclave reached 65 ° C. was 0.53 MPa (5.4 kg / cm ² ). The reaction was continued for 8 hours while maintaining the temperature at 65 ° C. When the pressure reached 0.31 MPa (3.2 kg / cm ² ), the heating was stopped and the mixture was allowed to cool. When the internal temperature dropped to room temperature, unreacted monomers were driven out, the autoclave was opened, and the reaction solution was taken out. The obtained reaction solution was poured into a large excess of hexane, and the precipitated polymer was taken out by removing the solvent by decantation. Furthermore, this polymer was dissolved in a small amount of ethyl acetate, and the remaining monomer was completely removed by reprecipitation from hexane twice. After drying, 28 g of polymer was obtained. Next, 20 g of the polymer was dissolved in 100 mL of N, N-dimethylacetamide, and 11.4 g of acrylic acid chloride was added dropwise under ice cooling, followed by stirring at room temperature for 10 hours. Ethyl acetate is added to the reaction solution, washed with water, the organic layer is extracted and concentrated, and the resulting polymer is reprecipitated with hexane to give a perfluoroolefin copolymer (1) having the following structure, which is a functional fluorine-containing polymer. 19g was obtained. The resulting polymer had a refractive index of 1.421.

(Preparation of sol solution a)
A reactor equipped with a stirrer and a reflux condenser, 120 parts by mass of methyl ethyl ketone, 100 parts by mass of acryloyloxypropyltrimethoxysilane “KBM-5103” (manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate (trade name) : Kerop EP-12, manufactured by Hope Pharmaceutical Co., Ltd.) 3 parts by mass and mixed, 30 parts by mass of ion-exchanged water was added and reacted at 60 ° C. for 4 hours. Obtained. The obtained compound had a mass average molecular weight of 1,600, and among the components higher than the oligomer component, the component having a molecular weight of 1,000 to 20,000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of hollow silica dispersion a)
Hollow silica dispersion {particle size about 40-50 nm, shell thickness 6-8 nm, refractive index 1.31, solid content concentration 20%, main solvent isopropyl alcohol, particle size according to Preparation Example 4 of JP-A-2002-79616 Changed and produced} 500 parts by mass, 30.5 parts by mass of acryloyloxypropyltrimethoxysilane, and diisopropoxyaluminum ethyl acetoacetate (trade name: Kellop EP-12, manufactured by Hope Pharmaceutical Co., Ltd.) 1.51 parts by mass After adding and mixing parts, 9 parts by mass of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 mass parts of acetylacetone, and obtained the dispersion liquid. Then, while adding cyclohexanone so that the silica content was substantially constant, solvent replacement was performed by distillation under reduced pressure at a pressure of 30 Torr, and finally a hollow silica dispersion a having a solid content concentration of 20% by mass was obtained by adjusting the concentration. . The amount of IPA remaining in the obtained dispersion was analyzed by gas chromatography and found to be 0.5% by mass or less.

{Preparation of coating solution for low refractive index layer (LLL-1)}
62.5 parts by mass of the perfluoroolefin copolymer (1), 1.9 parts by mass of a terminal methacrylate group-containing silicone resin “X-22-164C” (manufactured by Shin-Etsu Chemical Co., Ltd.), photoradical generation The agent “Irgacure 907” (manufactured by Ciba Specialty Chemicals) 4.7 parts by mass was added to 1,390 parts by mass of methyl ethyl ketone and 43 parts by mass of cyclohexanone and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for low refractive index layer (LLL-1).

{Preparation of coating solution for low refractive index layer (LLL-2)}
Mixture "DPHA" of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate {Nippon Kayaku Co., Ltd.} 13.2 parts by mass, hollow silica dispersion a160 parts by mass, "RMS-033" {silicone compound, Gelest 2.8 parts by mass, photo radical generator "Irgacure 907" {manufactured by Ciba Specialty Chemicals Co., Ltd.} 0.8 parts by mass, sol solution a 24.8 parts by mass, methyl ethyl ketone 1162.4 parts by mass, and The mixture was added to 36 parts by mass of cyclohexanone and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for low refractive index layer (LLL-2).

{Preparation of coating solution for low refractive index layer (LLL-3)}
Mixture "DPHA" of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate {made by Nippon Kayaku Co., Ltd.} 5.6 parts by mass, 22.4 parts by mass of the perfluoroolefin copolymer (1), hollow 80 parts by mass of silica dispersion a, “RMS-033” {silicone compound, manufactured by Gelest Co., Ltd.} 2.8 parts by mass, photoradical generator “Irgacure 907” {manufactured by Ciba Specialty Chemicals Co., Ltd.} 0.8 mass Part, 24.8 parts by mass of sol liquid a were added to 1227.6 parts by mass of methyl ethyl ketone and 36 parts by mass of cyclohexanone and stirred. The solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for low refractive index layer (LLL-3).

{Preparation of coating solution for low refractive index layer (LLL-4)}
"DPHA" mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate {manufactured by Nippon Kayaku Co., Ltd.} 8.3 parts by mass, 33.0 parts by mass of the perfluoroolefin copolymer (1), MEK-ST-L "{organosilica sol, manufactured by Nissan Chemical Industries, average particle size 40-50 nm, solid content concentration 30% by mass} 36.7 parts by mass," RMS-033 "{silicone compound, Gelest } 4.1 parts by mass, photo radical generator “Irgacure 907” {manufactured by Ciba Specialty Chemicals Co., Ltd.} 1.2 parts by mass are added to 1277.2 parts by mass of methyl ethyl ketone and 40 parts by mass of cyclohexanone. Stir. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for low refractive index layer (LLL-4).

{Preparation of coating solution for low refractive index layer (LLL-5)}
Mixture “DPHA” of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate {manufactured by Nippon Kayaku Co., Ltd.}, 8.3 parts by mass, 33.0 parts by mass of the perfluoroolefin copolymer (1), hollow Silica dispersion {particle size about 40-50 nm, shell thickness 6-8 nm, refractive index 1.31, solid content concentration 20%, main solvent isopropyl alcohol, particle size changed according to Preparation Example 4 of JP-A-2002-79616 55 parts by mass, "RMS-033" {silicone compound, manufactured by Gelest Co., Ltd.} 4.1 parts by mass, photo radical generator "Irgacure 907" {manufactured by Ciba Specialty Chemicals Co., Ltd.} 1.2 Part by mass was added to 1259.4 parts by mass of methyl ethyl ketone and 39 parts by mass of cyclohexanone and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for low refractive index layer (LLL-5).

{Preparation of coating solution for low refractive index layer (LLL-6)}
"DPHA" mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate {manufactured by Nippon Kayaku Co., Ltd.} 8.3 parts by mass, 33.0 parts by mass of the perfluoroolefin copolymer (1), IPA-ST-L "{organosilica sol, manufactured by Nissan Chemical Industries, average particle size 40-50 nm, solid content concentration 30% by mass} 36.7 parts by mass," RMS-033 "{silicone compound, Gelest } 4.1 parts by mass, photo radical generator “Irgacure 907” {manufactured by Ciba Specialty Chemicals Co., Ltd.} 1.2 parts by mass are added to 1277.2 parts by mass of methyl ethyl ketone and 40 parts by mass of cyclohexanone. Stir. The solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for low refractive index layer (LLL-6).

{Preparation of coating solution for low refractive index layer (LLL-7)}
45.9 parts by mass of Si (OC ₂ H ₅ ) _{4 and} 6.6 parts by mass of CF ₃ (CF ₃ ) ₇ (CH ₂ ) ₂ Si (OCH ₃ ) ₃ were added to 1155 parts by mass of methyl ethyl ketone and stirred. In the mixed solution, the hollow silica dispersion {particle size of about 40 to 50 nm, shell thickness of 6 to 8 nm, refractive index of 1.31, solid content concentration of 20%, main solvent isopropyl alcohol, preparation example 4 of JP-A-2002-79616 According to the same procedure, the particle size was changed to 112.5 parts by mass and 180 parts by mass of 0.1 mol / L hydrochloric acid were 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 low refractive index layer (LLL-7).

{Preparation of coating solution for low refractive index layer (LLL-8)}
Opstar JTA113 {thermally crosslinkable fluorine-containing silicone polymer composition liquid (solid content 6%): manufactured by JSR Corporation} 783.3 parts by mass {47.0 parts by mass as solids}, hollow silica dispersion a 195 parts by mass, colloidal silica dispersion {silica, MEK-ST particle size different product, average particle size 45 nm, solid content concentration 30%, manufactured by Nissan Chemical Co., Ltd.} 30.0 parts by mass (9. solid content) 0 parts by mass), 17.2 parts by mass of sol liquid a {5.0 parts by mass as a solid content} was added. The coating liquid (LLL-8) was prepared by diluting with cyclohexane and methyl ethyl ketone so that the solid content concentration of the entire coating liquid was 6% by mass and the ratio of cyclohexane and methyl ethyl ketone was 10:90.

{Preparation of coating solution for low refractive index layer (LLL-9)}
Opstar JTA113 {Heat-crosslinkable fluorine-containing silicone polymer composition (solid content: 6%): manufactured by JSR Corporation} with respect to 941.7 parts by mass (56.5 parts by mass as solids), colloidal silica dispersion { Silica, MEK-ST particle size difference product, average particle size 45 nm, solid content concentration 30%, manufactured by Nissan Chemical Co., Ltd.} 100.0 parts by mass (30.0 parts by mass as solids), sol solution a 46. 6 parts by mass (13.5 parts by mass as a solid content) was added. A coating solution (LLL-9) was prepared by diluting with cyclohexane and methyl ethyl ketone so that the solid content concentration of the entire coating solution was 6% by mass and the ratio of cyclohexane and methyl ethyl ketone was 10:90.

[Preparation of overcoat layer coating solution (OCLL)]
A fluorine-containing polymer having the structure shown below was synthesized.

  The molecular weight of this fluoropolymer was 40,000 in terms of number average molecular weight and 70,000 in terms of mass average molecular weight. This polymer was dissolved in methyl isobutyl ketone to prepare a 0.1% by mass solution. Further, p-toluenesulfonic acid was added as a curing catalyst so as to have a polymer solid content of 1% by mass to prepare a coating solution for an overcoat layer.

Example 1-1
[Preparation of Antireflection Film (AF-1)]
On a triacetyl cellulose film “TD80UF” {manufactured by Fuji Photo Film Co., Ltd.} having a thickness of 80 μm, a hard coat layer coating solution (HCLL) was applied using a gravure coater. After drying at 100 ° C., using a 160 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% by volume or less, an illuminance of 400 mW / The coating layer was cured by irradiating with an ultraviolet ray of cm ² and an irradiation amount of 300 mJ / cm ² to form a hard coat layer (HCL) having a thickness of 8 μm.

  Three coating solutions for medium refractive index layer (MLL-1), high refractive index layer coating solution (HLL-1), and low refractive index layer coating solution (LLL-1) are provided on the hard coat layer (HCL). Coating was performed continuously using a gravure coater having two coating stations.

The medium refractive index layer (ML-1) uses the medium refractive index layer coating solution (MLL-1), the drying conditions are 90 ° C. and 30 seconds, and the ultraviolet curing conditions are such that the oxygen concentration is 1.0% by volume or less. While purging with nitrogen so as to obtain an atmosphere of 1, a 180 W / cm air-cooled metal halide lamp {manufactured by Eye Graphics Co., Ltd.} was used to obtain an irradiation amount of 400 mW / cm ² and an irradiation amount of 400 mJ / cm ² .
The drying rate was 0.55 g / m ² · sec, and the cured medium refractive index layer (ML-1) had a refractive index of 1.630 and a film thickness of 67 nm.

The high refractive index layer (HL-1) uses a coating liquid for high refractive index layer (HLL-1), the drying conditions are 90 ° C. and 30 seconds, and the ultraviolet curing conditions are such that the oxygen concentration is 1.0% by volume or less. While purging with nitrogen to an atmosphere, a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) was used to obtain an irradiation intensity of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² .
The drying rate was 0.67 g / m ² · sec, and the high refractive index layer after curing had a refractive index of 1.905 and a film thickness of 107 nm.

The low refractive index layer (LL-1) uses a coating solution for low refractive index layer (LLL-1), the drying conditions are 90 ° C. and 30 seconds, and the ultraviolet curing conditions are such that the oxygen concentration is 0.1% by volume or less. While purging with nitrogen to an atmosphere, a 240 W / cm air-cooled metal halide lamp {manufactured by Eye Graphics Co., Ltd.) was used to obtain an irradiation intensity of 600 mW / cm ² and an irradiation amount of 600 mJ / cm ² . The drying rate was 0.35 g / m ² · sec, and the low refractive index layer after curing had a refractive index of 1.445 and a film thickness of 85 nm. In this way, an antireflection film (AF-1) was produced.

Examples 1-2 to 1-4
[Preparation of Antireflection Films (AF-2) to (AF-4)]
In Example 1-1, instead of using the low refractive index layer coating liquid (LLL-1), the low refractive index layer coating liquids (LLL-2) to (LLL-4) are used for low refraction. Antireflection films (AF-2) to (AF-4) were produced in the same manner as in Example 1-1 except that the rate layers (LL-2) to (LL-4) were formed. The drying rates are 0.31, 0.30, and 0.36 g / m ² · sec, respectively. The refractive indexes of the low refractive index layers after curing are 1.445, 1.440, and 1.450, respectively. Both were 85 nm.

Example 1-5
[Preparation of antireflection film (AF-5)]
In Example 1-1, instead of forming the low refractive index layer (LL-1) by coating the low refractive index layer coating solution (LLL-1), a dual magnetron using SiO ₂ with a traveling sputtering apparatus is used. An antireflection film (AF-5) was produced in the same manner as in Example 1-1 except that a low refractive index layer (MTL) made of a metal oxide thin film was formed by sputtering. At this time, the amount of oxygen was controlled by a plasma emission monitor method. The degree of vacuum was 0.27 Pa. The low refractive index layer had a refractive index of 1.460 and a film thickness of 85 nm.

Example 1-6
[Preparation of antireflection film (AF-6)]
In Example 1-3, three coating solutions for the medium refractive index layer (MLL-1), the high refractive index layer coating solution (HLL-1), and the low refractive index layer coating solution (LLL-3) were applied. Instead of forming a medium refractive index layer (ML-1), a high refractive index layer (HL-1) and a low refractive index layer (LL-3) by continuous application using a gravure coater having a station, medium refractive index The refractive index coating liquid (MLL-1) and the high refractive index layer coating liquid (HLL-1) are continuously applied using a gravure coater, and the medium refractive index layer (ML-1) and the high refractive index layer (HL). -1) Example 1-1, except that after the formation, the low refractive index layer coating liquid (LLL-3) was applied using a die coater to form the low refractive index layer (LL-3 ₂ ). In the same manner as above, an antireflection film (AF-6) was produced. The drying rate was 0.30 g / m ² · sec, and the low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 85 nm.

Comparative Examples 1-1 and 1-2
[Preparation of antireflection films (AF-7) and (AF-8)]
In Example 1-1, a low refractive index layer (LLL-5) or (LLL-6) was used instead of the low refractive index layer coating liquid (LLL-1). Antireflection films (AF-7) and (AF-8) were produced in the same manner as in Example 1-1 except that LL-5) or (LL-6) was formed. The drying rates were 0.42 and 0.45 g / m ² · sec, respectively, and the low refractive index layer after curing had a refractive index of 1.435 and 1.450 and a film thickness of 85 nm.

Example 1-7
[Preparation of antireflection film (AF-9)]
In Example 1-1, instead of using the coating solution for low refractive index layer (LLL-1), the coating solution for low refractive index layer (LLL-7) was used, and the drying condition was reduced to 120 ° C. for 1 minute. An antireflection film (AF-9) was produced in the same manner as in Example 1-1 except that the refractive index layer (LL-7) was formed. The drying rate was 0.49 g / m ² · sec, and the low refractive index layer after curing had a refractive index of 1.390 and a film thickness of 85 nm.

Example 1-8
[Preparation of antireflection film (AF-10)]
On the low refractive index layer (LL-7) produced in Example 1-7, an overcoat layer coating solution (OCLL) was further dried at 120 ° C. for 30 minutes to form an overcoat layer having a thickness of 10 nm. An antireflection film (AF-10) was produced in the same manner as in Example 1-7 except that (OCL) was produced.

Example 1-9
[Preparation of Antireflection Film (AF-11)]
In Examples 1-3, to form a high refractive index layer coating solution for middle refractive index layer not provided (HL-1) (MLL- 1) medium refractive index layer by changing the coating amount of (ML-1 ₂₎ The coating solution for low refractive index layer (LLL-3) is directly applied thereon, and the coating amount is changed to form the low refractive index layer (LL-3 ₃ ). Similarly, an antireflection film (AF-11) was produced. The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 100 nm, and the low refractive index layer had a refractive index of 1.440 and a film thickness of 100 nm. In the structure of the antireflection film (AF-11) described above, the middle refractive index layer (ML-1 ₂₎ is a high refractive index layer in the sense that it has a higher refractive index than the transparent support, carried In the description of the examples, the medium refractive index layer is used for convenience.

Example 1-10
[Preparation of antireflection film (AF-12)]
In Example 1-3, the medium refractive index layer (ML-1) and the high refractive index layer (HL-1) are not provided, and the coating liquid for low refractive index layer (LLL-) is directly formed on the hard coat layer (HCL). An antireflection film (AF-12) was produced in the same manner as in Example 1-3, except that 3)) was applied at different coating amounts to form a low refractive index layer (LL-3 ₄ ). . The low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 95 nm.

Example 1-11
[Preparation of antireflection film (AF-15)]
On a triacetyl cellulose film “TD80UF” {manufactured by Fuji Photo Film Co., Ltd.} having a thickness of 80 μm, a hard coat layer coating solution (HCLL-2) was applied using a gravure coater. After drying at 100 ° C., using a 160 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% by volume or less, an illuminance of 400 mW / The coating layer was cured by irradiating with an ultraviolet ray of cm ² and an irradiation amount of 100 mJ / cm ² to form a hard coat layer (HCL-2) having a thickness of 8 μm.

For the low refractive index layer (LL-8), the coating solution for low refractive index layer (LLL-8) is used. The drying conditions are 90 ° C. and 30 seconds, and then heat curing is performed at 110 ° C. for 10 minutes. Using a 240 W / cm air-cooled metal halide lamp {manufactured by Eye Graphics Co., Ltd.} while purging with nitrogen so that the oxygen concentration becomes an atmosphere of 0.1% by volume or less, an illuminance of 400 mW / cm ² and an irradiation amount of 300 mJ / The irradiation dose was cm ² . The drying rate was 0.33 g / m ² · sec, and the low refractive index layer after curing had a refractive index of 1.422 and a film thickness of 89 nm. In this way, an antireflection film (AF-15) was produced.

Example 1-12
[Preparation of antireflection film (AF-16)]
In Example 1-11, instead of using the coating liquid for hard coat layer (HCLL-2) and the coating liquid for low refractive index layer (LLL-8), the coating liquid for hard coat layer (HCLL-3), low refractive index An antireflection film (like the case of Example 1-11), except that the hard coat layer (HCL-3) and the low refractive index layer (LL-9) were formed using the coating liquid for rate layer (LLL-9), respectively. AF-16) was produced. The drying speed was 0.34 g / m ² · sec, and the low refractive index layer after curing had a refractive index of 1.445 and a film thickness of 88 nm.

Comparative Example 1-3
[Preparation of antireflection film (AF-13)]
In Example 1-3, after the low refractive index layer coating liquid (LLL-3) was applied, the low refractive index layer (LL-3 ₅ ) was formed at a drying rate of 0.06 g / m ² · sec. Produced an antireflection film (AF-13) in the same manner as in Example 1-3. The low refractive index layer after curing had a refractive index of 1.450 and a film thickness of 86 nm.

Comparative Example 1-4
[Preparation of antireflection film (AF-14)]
In Example 1-2, instead of using the medium refractive index layer coating liquid (MLL-1) and the high refractive index layer coating liquid (HLL-1), the medium refractive index layer coating liquid (MLL-2) and Reflecting in the same manner as in Example 1-2, except that the medium refractive index layer (ML-2) and the high refractive index layer (HL-2) were formed using the coating liquid for high refractive index layer (HLL-2). A prevention film (AF-14) was produced. The medium / high refractive index layer after curing had a refractive index of 1.630 / 1.905 and a film thickness of 67/107 nm.

  The composition and the like of the obtained antireflection film are summarized in Table 1 below.

[Evaluation of antireflection film (AF)]
The following items were evaluated for the film samples obtained after the saponification treatment.

(1) Specular reflectance and tint Spectral photometer "V-550" {manufactured by JASCO Corporation} with adapter "ARV-474" and each antireflection film sample in a wavelength range of 380 to 780 nm The specular reflectance at an emission angle of -5 ° at an incident angle of 5 ° was measured, the average reflectance in the region of 450 to 650 nm was calculated, and the antireflection property was evaluated. Furthermore, from the measured reflectance spectra, L ^* value of the CIE1976L ^* a ^* b ^* color space representing the color of specular reflection light with respect to an incident angle of 5 ° incident light CIE standard light source D _65, a ^* value, b ^* The value was calculated, and the color of reflected light was evaluated using the a ^* value and b ^* value.

(2) Whiteness The whiteness of each antireflection film sample was evaluated as follows.
A polarizing film was bonded to both surfaces of a 10 cm square glass plate in a crossed Nicol arrangement, and each antireflection film sample was bonded with the antireflection layer surface facing upward. The whiteness was ranked visually from a position 2 m away from a bare fluorescent lamp (8000 cd / m ² ) without a louver.
1: Clear without whiteness.
2: Almost no whiteness and almost clear.
3: Slight whiteness is felt.
4: Feels quite white.

(3) Amount of scattered light The value of I ₅₀ as the amount of scattered light of each antireflection film sample was measured using a goniophotometer “GP-5” (manufactured by Murakami Color Research Laboratory). The value of I ₅₀ is incident on the surface of the antireflection film from a direction inclined by −10 ° from the normal line standing on the sample surface, and is scattered by + 50 ° from the normal line among the scattered light scattered on the surface of the antireflection film. The value of the amount of scattered light in the specified direction was read.

(4) Arithmetic average roughness (Ra), ten-point average roughness (Rz), average inclination angle The arithmetic average roughness (Ra), ten-point average roughness (Rz), average inclination angle of each antireflection film sample is And a scanning probe microscope “SPI3800” {manufactured by Seiko Instruments Inc.}.

(5) Reflection The image display device equipped with each antireflection film sample was displayed in black, and a white shirt was reflected from a place 1.5 m away from the image display device.
Reflection was evaluated according to the following criteria.
○: It looks faint but I don't mind.
Δ: A little worrisome
X: I am quite worried.

(6) Surface morphology observation The particle aggregation state of the low refractive index layer containing inorganic fine particles in each antireflection film sample was measured by using a scanning electron microscope “S-570” {manufactured by Hitachi, Ltd.} to accelerate voltage. Observation was performed at 10 kV and a magnification of 10,000 times. The mass of particles aggregated by visual observation and particle aggregation was defined as one circle, and the diameter was evaluated according to the following criteria. In addition, about Example 1-1 and Example 1-5 which do not contain an inorganic fine particle, since there was no aggregation of particle | grains, it was set as-.
(Double-circle): Particle aggregation is hardly seen but is disperse | distributing uniformly.
○: Particle aggregation is slightly observed, but is almost uniformly dispersed.
Δ: Agglomeration is observed and not uniformly dispersed.
X: Many aggregations are observed and dispersion is not uniform.

(7) Steel Wool Scratch Resistance Evaluation Using a rubbing tester, the surface of each antireflection film sample was rubbed under the following conditions.
Evaluation environmental conditions: 25 ° C., 60% RH
Rub material: Steel wool “Gelade No. 0000” (manufactured by Nippon Steel Wool Co., Ltd.) was wound around the rubbing tip (1 cm × 1 cm) of a tester in contact with the sample, and the band was fixed so as not to move.
Moving distance (one way): 13 cm, rubbing speed: 13 cm / sec, load: 500 g / cm ² ,
Tip contact area: 1 cm × 1 cm, rubbing frequency: 10 reciprocations.
An oil-based black ink was applied to the back side of the rubbed sample and visually observed with reflected light, and scratches on the rubbed portion were evaluated according to the following criteria.
A: Even when viewed very carefully, no scratches are visible.
○: Slightly weak scratches are visible when viewed very carefully.
○ △: Weak scratches are visible.
Δ: Moderate scratches are visible.
Δ × ˜ ×: There is a scratch that can be seen at first glance.

(8) Adhesion evaluation The surface on the side having the low refractive index layer of each antireflection film sample was cut into 11 vertical and 11 horizontal cuts with a cutter knife, for a total of 100 square squares. The polyester adhesive tape “No. 31B” manufactured by Nitto Denko Corporation was crimped, and the adhesion test 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.
◎: No peeling was observed in 100 squares ○: No peeling was observed in 100 squares within 2 squares △: peeling was observed in 100 squares 3 to 10 mm ×: The one in which peeling was observed in 100 cells exceeded 10 mm

(9) Evaluation of antifouling property The oil-based pen “Mackey Care” {manufactured by Zebra} attached to the surface of each antireflective film sample having the low refractive index layer is made of cellulose nonwoven fabric “Bencot M-3” {Asahi Kasei ( The product was wiped off and the ease of removal was evaluated by the following two steps.
○: The oil pen can be completely wiped off.
X: A trace of wiping off the oil pen remains.

(10) Evaluation of dustiness The transparent support side of each antireflection film sample was attached to the CRT surface, and in a room having 1 to ² million dusts and tissue paper wastes of 0.5 μm or more per 1 ft ³ (cubic feet). Used for hours. The number of adhering dust and tissue paper waste is measured per 100 cm ^{2 of the} antireflection film, and the average value of each result is less than 20, A is 20 to 49, B is 50 to 199 Was evaluated as C, and the case of 200 or more was evaluated as D.

(11) Chemical resistance test A mask with a hole of 7 mmφ is put on the surface of each antireflection film sample having the low refractive index layer, and “Magicrin” {manufactured by Kao Corporation} is separated from the sample by 30 cm. Sprayed from a distance. After leaving for 5 minutes, the remaining liquid and liquid traces were wiped off, and whether or not abnormalities were observed on the surface was evaluated according to the following three steps.
○: No abnormality is observed on the film surface before and after the evaluation.
Δ: Some abnormality is observed on the film surface before and after the evaluation.
X: Abnormality is clearly observed on the film surface before and after evaluation.

(12) Light resistance test For each antireflection film sample, a sunshine weather meter (SX-75, manufactured by Suga Test Instruments Co., Ltd.) was used, a sunshine carbon arc lamp, irradiance 150 W / m ² , humidity 50% RH, 200 The light resistance test was conducted under the conditions of time.
About each sample after a test, the adhesiveness test was done like the previous (8) term.

As shown in Table 2, the antireflection films of Examples 1-1 to 1-12 had high antireflection properties, both the average reflectance and the amount of scattered light were within the scope of the present invention, and were excellent in whiteness. Moreover, the color of the reflection was neutral.
On the other hand, Comparative Examples 1-1 to 1-2 and Comparative Example 1-3 in which the drying rate is outside the preferred range have aggregation of inorganic fine particles in the low refractive index layer, and the amount of scattered light is outside the range of the present invention. Whiteness also worsened. In Comparative Examples 1-1 to 1-2, it is considered that the aggregation of silica progressed due to the coexistence of the hydrophobic perfluoroolefin copolymer (1) and hydrophilic silica. In Comparative Example 1-3, it is considered that the increase in viscosity takes place until the fluidity of the silica particles is lost due to the slow drying rate, and the aggregation of the silica proceeds. In Comparative Example 1-4, coarse particles of titanium dioxide were present in the high refractive index layer and the middle refractive index layer, the amount of scattered light was outside the range of the present invention, and whiteness was conspicuous.
Further, in Example 1-1 in which the inorganic fine particles are not present in the low refractive index layer, dustiness is slightly lowered, and Example 1-5 in which the low refractive index layer is a metal oxide thin film layer is antifouling property. Decreased. In Example 1-7 in which a low refractive index layer was formed without using a functional fluorine-containing polymer, dust resistance and chemical resistance reduced the refractive index of the high refractive index layer (medium refractive index layer (ML- Example 1-9 using 1 ₂ ) and Example 1-10 prepared without providing a high refractive index layer were slightly inferior in terms of reflection.
Moreover, all of the antireflection films of Examples 1-1 to 1-7 exhibited high light resistance.

Example 2
[Evaluation of image display device]
The image display devices equipped with the antireflection films of the present invention produced in Examples 1-1 to 1-12 were excellent in antireflection performance and exhibited extremely excellent visibility without whiteness.

Example 3
[Production of protective film for polarizing plate]
In the antireflection film produced in Examples 1-1 to 1-12, on the surface of the transparent support opposite to the side having the antireflection film of the present invention, 57 parts by mass of potassium hydroxide and 120 parts by mass of propylene glycol Then, a saponification solution in which an alkali solution consisting of 535 parts by mass of isopropyl alcohol and 288 parts by mass of water was kept at 40 ° C. was applied to saponify the surface of the transparent support.

  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]
[Preparation of polarizing film]
A polyvinyl alcohol film (made by Kuraray Co., Ltd.) having a film thickness of 75 μm was immersed in an aqueous solution consisting of 1000 g of water, 7 g of iodine and 10.5 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.

  Next, using a polyvinyl alcohol adhesive as an adhesive, the saponified triacetyl cellulose surface of each antireflection film of the present invention (protective film for polarizing plate) was bonded to one surface of the polarizing film. . Further, a cellulose acylate film “TD-80UF” (manufactured by Fuji Photo Film Co., Ltd.) saponified in the same manner as above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive. .

[Evaluation of image display device]
Each of the polarizing plates of the present invention thus prepared was mounted on a TN, STN, IPS, VA, OCB mode transmission type, reflection type or semi-transmission type liquid crystal display device and evaluated manually. These liquid crystal display devices were all excellent in antireflection performance and extremely excellent in visibility.

Example 4
[Preparation of polarizing plate]
The surface of the optical compensation film “Wide View Film A 12B” {manufactured by Fuji Photo Film Co., Ltd.) opposite to the side having the optical compensation layer was saponified under the same conditions as in Example 3.

  Next, the antireflection film (protective film for polarizing plate) prepared in Example 3 was applied to one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive for the polarizing film prepared in Example 3. The saponified triacetyl cellulose surfaces were bonded together. 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]
Each polarizing plate of the present invention produced in this way was mounted on a TN, STN, IPS, VA, OCB mode transmissive, reflective, or transflective liquid crystal display device and evaluated. These liquid crystal display devices do not use an optical compensation film and are superior in contrast in a bright room than the liquid crystal display device equipped with the polarizing plate, and have a very wide viewing angle in the vertical and horizontal directions. Excellent anti-reflection performance and extremely excellent visibility and display quality.

As described in detail in the present specification, by forming the antireflection film according to the present invention on a transparent support such as cellulose acylate, an antireflection film having no whiteness and excellent clearness can be obtained at low cost. Can be provided in large quantities.
Furthermore, the polarizing plate and image display apparatus which hold | maintained the said outstanding characteristic by these can be provided.

FIG. 1 is a cross-sectional view schematically showing a layer structure when the multilayer antireflection film of the present invention is used as a surface protective film on one side of a polarizing plate.

FIG. 2 shows an apparatus configuration used for forming a plurality of optical thin films of the antireflection film of the present invention in a process consisting of feeding the support film once, forming each optical thin film and winding the film. It is an example.

Explanation of symbols

1: Transparent support.
2: Hard coat layer.
3: Medium refractive index layer.
4: High refractive index layer.
5: Low refractive index layer (outermost layer).
10: Antireflection film.
11: Antireflection film.
6: Adhesive layer.
7: Polarizing film.
8: Surface protective film on the opposite side.
9: Adhesive layer.

101: Delivery of roll film.
102: First application station.
103: First drying zone.
104: First UV irradiator.
105: Second application station.
106: Second drying zone.
107: Second UV irradiator.
108: Third application station.
109: Third drying zone.
110: Third UV irradiator.
111: post-drying zone.
112: Roll film winding.

Claims (21)

An antireflection film in which an antireflection film comprising at least one thin layer having a refractive index different from that of the transparent support is coated on the transparent support, and the average value of the specular reflectance is suppressed to 3% or less. In
Of scattered light scattered on the surface of the antireflection film, incident light on the surface of the antireflection film from a direction inclined by -10 ° from the normal line standing on the surface of the transparent support, + 50 ° from the normal line. An antireflection film, wherein the amount of scattered light I _{50 in the} tilted direction and the total amount of light I of all scattered light of the incident light satisfy the relationship of the following formula (1).
Formula (1): -Log (I ₅₀ /I)≧6.6.   The arithmetic average roughness Ra of the outermost surface on the antireflection film forming side of the antireflection film is 0.1 to 15 nm, the ratio Rz / Ra of the ten-point average roughness Rz to Ra is 15 or less, and the average inclination angle of the concavo-convex profile ( The antireflection film according to claim 1, which has a fine uneven shape having an average inclination angle with respect to the regular reflection surface of 3 ° or less.   The antireflection film according to claim 1 or 2, wherein the antireflection film comprises at least a low refractive index layer having a refractive index lower than that of the transparent support.   The reflection according to claim 3, wherein the low refractive index layer is a cured film formed by coating a composition for forming a low refractive index layer containing at least one selected from thermosetting and radiation curable compositions. Prevention film.   The antireflection film according to any one of claims 1 to 4, wherein an average value of the specular reflectance is 1% or less.   The antireflection film according to claim 3 or 4, wherein the refractive index of the low refractive index layer is in the range of 1.20 to 1.49.   The antireflection film according to claim 3, 4 or 6, wherein a difference between the low refractive index layer and the refractive index of a layer adjacent to the low refractive index layer is 0.16 or more and 1.3 or less.   The antireflection film has at least one high-refractive index layer having a higher refractive index than that of the support between the transparent support and the low-refractive index layer. The antireflection film as described. An antireflection film comprises a high refractive index layer having a refractive index higher than that of the support, in order from the low refractive index layer side between the transparent support and the low refractive index layer, and the support and the high refractive index. It has a three-layer structure of a medium refractive index layer having an intermediate refractive index of the refractive index layer. For the design wavelength λ (400 to 680 nm), the medium refractive index layer represents the following formula (2), The antireflection film according to claim 3, wherein the low refractive index layer satisfies the following formula (3) and the following formula (4).
Formula (2): (λ / 4) × 0.80 <n ₁ d ₁ <(λ / 4) × 1.00
Formula (3): (λ / 2) × 0.75 <n ₂ d ₂ <(λ / 2) × 0.95
Formula (4): (λ / 4) × 0.95 <n ₃ d ₃ <(λ / 4) × 1.05
[Where n ₁ is the refractive index of the medium refractive index layer, d ₁ is the layer thickness (nm) of the medium refractive index layer; n ₂ is the refractive index of the high refractive index layer, and d ₂ is the high refractive index layer. Layer thickness (nm); n ₃ is the refractive index of the low refractive index layer, and d ₃ is the layer thickness (nm) of the low refractive index layer] Regularly reflected light in color with respect to the incident angle of 5 ° incident light CIE standard light source D65 from wavelength 380nm at 780nm areas, CIE1976L ^* a ^* b ^* color space a ^*, b ^* values, respectively -8 ≦ a ^The antireflection film according to claim 1, wherein ^* ≦ 8 and −10 ≦ b ^* ≦ 10.   The antireflection film according to claim 3, wherein the low refractive index layer contains 5 to 80 mass% of inorganic fine particles having an average particle diameter of 5 to 100 nm. The antireflection film according to claim 11, wherein the inorganic fine particles have been subjected to a dispersibility improving treatment with a hydrolyzate of organosilane represented by the following general formula (1) and / or a partial condensate thereof.
General formula (1):
(R ¹¹ ) α-Si (Y ¹¹ ) _4- α
(In the formula, R ¹¹ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. Y ¹¹ represents a hydroxyl group or a hydrolyzable group. Α represents an integer of 1 to 3) The antireflection film according to claim 12, wherein the dispersibility improving treatment is performed in the presence of at least one of an acid catalyst and the following metal chelate compound.
Metal chelate compound: alcohol represented by general formula R ⁰¹ OH (where R ⁰¹ represents an alkyl group having 1 to 10 carbon atoms) and general formula R ⁰² COCH ₂ COR ⁰³ (where R ⁰² is carbon the number of 1 to 10 alkyl group, R ⁰³ had at least one selected from compounds represented by indicating.) an alkyl group or an alkoxy group having 1 to 10 carbon atoms having 1 to 10 carbon atoms and ligands At least one metal chelate compound having a metal selected from Zr, Ti and Al as a central metal.   The antireflection film according to any one of claims 11 to 13, wherein the inorganic fine particles have a hollow structure.   An overcoat layer containing at least one compound selected from a fluorine-containing compound, a silicon-containing compound, and a long-chain alkyl group-containing compound having 4 or more carbon atoms is laminated on the low refractive index layer. 14. The antireflection film according to 14.   The high refractive index layer contains inorganic fine particles mainly containing titanium dioxide containing at least one element selected from cobalt, aluminum, and zirconium, and the refractive index of the high refractive index layer is 1.55. It is -2.50. The antireflection film in any one of Claims 8-15.   The manufacturing method of the antireflection film of Claims 1-16.   A polarizing plate having at least one protective film on the surface of the polarizing film, wherein the protective film is the antireflection film according to claim 1.   The antireflection film according to any one of claims 1 to 16 is used as one protective film of a polarizing film, and an optical compensation film having optical anisotropy is used as the other protective film of the polarizing film. A polarizing plate.   An image display device, wherein the antireflection film according to claim 1 or the polarizing plate according to claim 18 or 19 is disposed on an image display surface.   The image display device according to claim 20, wherein the TN, STN, VA, IPS, or OCB mode transmissive, reflective, or transflective liquid crystal display device.

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