WO2015152308A1

WO2015152308A1 - Anti-reflection film, polarizing plate, cover glass, image display device and method for producing anti-reflection film

Info

Publication number: WO2015152308A1
Application number: PCT/JP2015/060278
Authority: WO
Inventors: 美帆朝日; 彩子松本; 伊吹　俊太郎; 真内村
Original assignee: 富士フイルム株式会社
Priority date: 2014-03-31
Filing date: 2015-03-31
Publication date: 2015-10-08

Abstract

An anti-reflection film which comprises a base and an anti-reflection layer that is formed from an anti-reflection layer-forming composition containing the components (A), (B) and (C) described below, and wherein: the anti-reflection layer contains a binder resin that comprises a structure derived from the component (B) and/or a structure derived from the component (C); the anti-reflection layer has a moth eye structure on a surface that is on the reverse side of the base-side interface, said moth eye structure being formed of a recessed and projected pattern formed by metal oxide particles of the component (A); and the recessed and projected pattern of the anti-reflection layer is configured such that the ratio of the distance B between a recess and the central point between the apexes of two adjacent projections to the distance A between the apexes of two adjacent projections, namely B/A is 0.5 or more. A polarizing plate, a cover glass and an image display device, each of which comprises this anti-reflection film; and a method for producing this anti-reflection film. (A) Metal oxide particles having an average primary particle diameter of from 50 nm to 380 nm (inclusive), each of which has a hydroxyl group on the surface. (B) A compound having a weight average molecular weight of 1,000 or less and having three or more polymerizable groups in each molecule, said polymerizable groups being (meth)acryloyl groups or polymerizable groups other than (meth)acryloyl groups configured only of atoms selected from among a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom. (C) A compound having a weight average molecular weight of from 300 to 1,000 (inclusive) and having a (meth)acryloyl group and a silicon atom to which a hydroxyl group and/or a hydrolyzable group is directly bonded. An anti-reflection film which comprises a base and an anti-reflection layer that contains a binder resin and metal oxide particles having an average primary particle diameter of from 50 nm to 250 nm (inclusive), and wherein: the amount of the hydroxyl groups on the surfaces of the metal oxide particles is 1.00 × 10^-1 or less; the metal oxide particles have an indentation hardness of 400 MPa or more; the binder resin is a resin having a hydroxyl group; and the anti-reflection layer has a moth eye structure on a surface that is on the reverse side of the base-side interface, said moth eye structure being formed of a recessed and projected pattern formed by the metal oxide particles. A polarizing plate, a cover glass and an image display device, each of which comprises this anti-reflection film; and a method for producing this anti-reflection film.

Description

Antireflection film, polarizing plate, cover glass, image display device, and production method of antireflection film

The present invention relates to an antireflection film, a polarizing plate, a cover glass, an image display device, and a method for producing the antireflection film.

In image display devices such as cathode ray tube display (CRT), plasma display (PDP), electroluminescence display (ELD), fluorescent display (VFD), field emission display (FED), and liquid crystal display (LCD), An antireflection film may be provided in order to prevent a decrease in contrast and reflection of an image due to reflection of external light on the display surface. In addition to the image display device, an antireflection function may be provided by an antireflection film.

As an antireflection film, an antireflection film having a fine unevenness with a period of not more than the wavelength of visible light on the surface of the substrate, that is, an antireflection film having a so-called moth eye structure is known. With the moth-eye structure, it is possible to create a refractive index gradient layer in which the refractive index continuously changes from air to the bulk material inside the substrate, thereby preventing light reflection.

As an antireflection film having a moth-eye structure, Patent Document 1 discloses that a coating liquid containing a transparent resin monomer and fine particles is applied on a transparent substrate and cured to form a transparent resin in which the fine particles are dispersed. An antireflection film having an uneven structure manufactured by etching a resin is described.
Patent Document 2 describes an antireflection member in which ultrafine particles are exposed in a state where they are fixed in the remaining portion of the cured binder layer by dry etching a cured binder layer containing ultrafine particles provided on a substrate. .
In Patent Document 3, a coating liquid containing tetraethoxysilane and ultrafine particles is applied onto a glass substrate and baked to fix ultrafine particles with a thin SiO ₂ film formed by decomposition of tetraethoxysilane. Manufacturing an antireflection body is described.

Japanese Unexamined Patent Publication No. 2009-139796 Japanese Unexamined Patent Publication No. 7-104103 Japanese Unexamined Patent Publication No. 5-13021

However, it has been found that the antireflection members described in Patent Documents 1 to 3 have a problem that the particles fall off when a strong stress is applied to the moth-eye structure formed by the particles.

In addition, the antireflection film described in Patent Document 1 shows that when a high pressure is applied in the thickness direction to the moth-eye structure formed by the particles, the particles are crushed, resulting in a problem that the antireflection function is lost. It was.
The present inventors examined this problem, and used metal oxide particles having a high indentation hardness and a small amount of hydroxyl groups on the surface as particles forming a moth-eye structure. As a result, durability against pressure in the thickness direction was improved. However, the dispersibility of the particles in the binder resin used for the antireflection layer is lowered, the particles are aggregated in the binder resin, and the haze of the antireflection layer is increased or the reflectance is increased. Problem has occurred.

The first object of the present invention is an antireflection film having a moth-eye structure on the surface, the anti-reflection film having a high pencil hardness of the moth-eye structure, and particles not falling off even when a strong stress is applied to the moth-eye structure. It is providing the manufacturing method of the polarizing plate containing a film, a cover glass, an image display apparatus, and an antireflection film.

Another object of the present invention is to provide an antireflection film having a moth-eye structure on the surface, which has high durability against pressure in the thickness direction of the moth-eye structure, low reflectance, and low haze. It is providing the manufacturing method of the polarizing plate containing an antireflection film, a cover glass, an image display apparatus, and an antireflection film.

As a result of intensive studies, the present inventors have found that the first problem can be solved by using a specific component as a material for forming an antireflection layer having a moth-eye structure.
That is, the first aspect of the present invention has the following configurations [1] to [14].

Further, as a result of intensive studies, the present inventors have used metal oxide particles having a high indentation hardness and a small amount of hydroxyl groups on the surface as particles forming the moth eye structure, and hydroxyl groups as the binder resin of the antireflection layer. It has been found that the above second problem can be solved by using a resin having the above.
That is, the second aspect of the present invention has the following configurations [2-1] to [2-18].

[1]
A substrate;
An antireflection film having an antireflection layer formed from the composition for forming an antireflection layer containing the following (A), (B) and (C),
The antireflection layer includes a binder resin including at least one of a structure derived from the following (B) and a structure derived from the following (C), and the following (on the surface opposite to the interface on the substrate side) ( A) having a moth-eye structure composed of irregularities formed of metal oxide particles of A),
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. An anti-reflection film.
(A) Metal oxide particles having a hydroxyl group on the surface and an average primary particle size of 50 nm or more and 380 nm or less.
(B) having a polymerizable group other than a (meth) acryloyl group composed of only a (meth) acryloyl group or an atom selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom as a polymerizable group; A compound having a weight average molecular weight of 1000 or less and having 3 or more polymerizable groups in the molecule.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.
[2]
The compound (C) is a carbon atom between a carbon atom constituting the carbonyl group in the (meth) acryloyl group and a silicon atom to which at least one of the hydroxyl group and the hydrolyzable group is directly bonded. The antireflective film according to [1], which is a compound having 4 or more.
[3]
The ratio of the number of (meth) acryloyl groups to the number of silicon atoms to which at least one of the hydroxyl group and hydrolyzable group of the compound (C) is directly bonded is 1.1 or more and 3.0 or less, The antireflection film according to [1] or [2].
[4]
The compound (C) is a urethane bond between the carbon atom constituting the carbonyl group in the (meth) acryloyl group and the silicon atom to which at least one of the hydroxyl group and the hydrolyzable group is directly bonded. The antireflection film according to any one of [1] to [3], which is a compound having
[5]
Any one of [1] to [4], wherein the ratio of the mass of (C) to the sum of the mass of (B) and the mass of (C) is 0.2 or more and 0.8 or less. The antireflection film as described in 1.
[6]
The antireflection film according to any one of [1] to [5], wherein the metal oxide particles (A) are metal oxide particles whose surface is modified with a compound having a (meth) acryloyl group.
[7]
The antireflection layer according to any one of [1] to [5], wherein in the composition for forming an antireflection layer, the metal oxide particles (A) are surface-modified with the compound (C). the film.
[8]
The antireflection film according to any one of [1] to [7], wherein the metal oxide particles are silica particles.
[9]
The antireflection film according to any one of [1] to [8], wherein the metal oxide particles are calcined silica particles.
[10]
The antireflection film according to any one of [1] to [9], which has a hard coat layer between the substrate and the antireflection layer.
[11]
A polarizing plate having a polarizer and at least one protective film for protecting the polarizer, wherein at least one of the protective films is the antireflection film according to any one of [1] to [10] A certain polarizing plate.
[12]
[1] A cover glass having the antireflection film according to any one of [10] as a protective film.
[13]
An image display device comprising the antireflection film according to any one of [1] to [10] or the polarizing plate according to [11].
[14]
A method for producing an antireflection film having a substrate and an antireflection layer,
The antireflection layer has a moth-eye structure having a concavo-convex shape formed by the metal oxide particles of the following (A) on the surface opposite to the interface on the substrate side,
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. And
The antireflection film which has the process of apply | coating the composition for antireflection layer containing the following (A), (B) and (C) on the said base material, and hardening the following (B) and (C). Manufacturing method.
(A) Metal oxide particles having a hydroxyl group on the surface and an average primary particle size of 50 nm or more and 380 nm or less.
(B) A compound having three or more (meth) acryloyl groups in one molecule and having a weight average molecular weight of 1,000 or less. However, when the compound (B) has a polymerizable group other than the (meth) acryloyl group, the polymerizable group is a polymerization composed only of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom. Sex group.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.

[2-1]
An antireflection film comprising a base material, an antireflection layer containing a binder resin and metal oxide particles having an average primary particle size of 50 nm to 250 nm,
The surface of the metal oxide particles has a hydroxyl group content of 1.00 × 10 ⁻¹ or less,
The indentation hardness of the metal oxide particles is 400 MPa or more,
The binder resin is a resin having a hydroxyl group,
The antireflection layer is an antireflection film having a moth-eye structure having a concavo-convex shape formed of the metal oxide particles on a surface opposite to the interface on the substrate side.
[2-2]
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. The antireflection film according to [2-1].
[2-3]
The antireflection film according to [2-1] or [2-2], which contains only metal oxide particles having a primary particle size of 50 nm or more and 250 nm or less as the metal oxide particles.
[2-4]
The antireflection film according to any one of [2-1] to [2-3], wherein the metal oxide particles are silica particles.
[2-5]
The antireflection film according to any one of [2-1] to [2-4], wherein the metal oxide particles are calcined silica particles.
[2-6]
The antireflection film according to any one of [2-1] to [2-5], wherein the metal oxide particles are calcined silica particles whose surface is modified with a compound having a (meth) acryloyl group.
[2-7]
The antireflection film as described in [2-2], wherein the half width of the distribution of the distance A is 200 nm or less.
[2-8]
The binder resin is a resin obtained by polymerizing a polymerizable compound having at least one of a group having an ethylenically unsaturated double bond and an epoxy group as a polymerizable group [2-1] to [2-7. ] The antireflection film of any one of.
[2-9]
The antireflective film according to [2-8], wherein one molecule of the polymerizable compound has a hydroxyl group equivalent of 1 to 10,000.
[2-10]
The antireflection film according to any one of [2-1] to [2-9], which has a hard coat layer between the substrate and the antireflection layer.
[2-11]
A polarizing plate having a polarizer and at least one protective film for protecting the polarizer, wherein at least one of the protective films is described in any one of [2-1] to [2-10] A polarizing plate which is an antireflection film.
[2-12]
A cover glass having the antireflection film according to any one of [2-1] to [2-10] as a protective film.
[2-13]
An image display device comprising the antireflection film according to any one of [2-1] to [2-10] or the polarizing plate according to [2-11].
[2-14]
A method for producing an antireflection film comprising a base material, and an antireflection layer containing a binder resin and metal oxide particles having an average primary particle size of 50 nm to 250 nm,
The surface of the metal oxide particles has a hydroxyl group content of 1.00 × 10 ⁻¹ or less,
The indentation hardness of the metal oxide particles is 400 MPa or more,
The binder resin is a resin having a hydroxyl group,
The antireflection layer has a moth-eye structure having an uneven shape formed by the metal oxide particles on the surface opposite to the interface on the base material side,
An antireflection layer-forming composition containing a polymerizable compound for forming a binder resin having a polymerizable functional group and metal oxide particles having an average primary particle size of 50 nm to 250 nm is applied on the base material. The manufacturing method of the antireflection film which has a process.
[2-15]
The metal oxide particles include both [2-1], [2-] metal oxide fine particles having an average primary particle size of 120 nm to 250 nm and metal oxide particles having an average primary particle size of 50 nm to less than 120 nm. [2] The antireflection film according to any one of [2-4] to [2-10].
[2-16]
The antireflection film according to [2-15], wherein the metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm have a hydroxyl group amount of 1.00 × 10 ⁻¹ or less and an indentation hardness of 400 MPa or more.
[2-17]
The antireflection film according to [2-15], wherein the metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm have a hydroxyl group amount of more than 1.00 × 10 ⁻¹ or an indentation hardness of less than 400 MPa.
[2-18]
[2-15] to [2-15] to [2-15] to [2-15] to [2-15] to [2-15 times higher than the metal oxide fine particles having an average primary particle size of 120 nm to 250 nm in a frequency of 2 to 5 times 2-17]. The antireflection film according to any one of 2-17].

According to the first aspect of the present invention, in the antireflection film having a moth-eye structure on the surface, the anti-reflection film has a high pencil hardness of the moth-eye structure and particles do not fall off even when a strong stress is applied to the moth-eye structure. A polarizing plate including an antireflection film, a cover glass, an image display device, and a method for manufacturing the antireflection film can be provided.

According to the second aspect of the present invention, an antireflection film having a moth-eye structure on the surface, having high durability against pressure in the thickness direction of the moth-eye structure, low reflectance, and low haze. Further, a polarizing plate, a cover glass, an image display device including the antireflection film, and a method for producing the antireflection film can be provided.

It is a cross-sectional schematic diagram which shows an example of the antireflection film of the 1st aspect and 2nd aspect of this invention.

Hereinafter, preferred embodiments of the present invention will be described in detail. The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, when numerical values represent physical property values, characteristic values, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”.
In addition, “(meth) acrylate” represents at least one of acrylate and methacrylate, “(meth) acryl” represents at least one of acrylic and methacryl, and “(meth) acryloyl” represents at least one of acryloyl and methacryloyl. .

<First embodiment of the present invention>
[Antireflection film]
The antireflection film of the first aspect of the present invention is
A substrate;
An antireflection film having an antireflection layer formed from the composition for forming an antireflection layer containing the following (A), (B) and (C),
The antireflection layer includes a binder resin including at least one of a structure derived from the following (B) and a structure derived from the following (C), and the following (on the surface opposite to the interface on the substrate side) ( A) having a moth-eye structure composed of irregularities formed of metal oxide particles of A),
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. It is an antireflection film.
(A) Metal oxide particles having a hydroxyl group on the surface and an average primary particle size of 50 nm or more and 380 nm or less.
(B) having a polymerizable group other than a (meth) acryloyl group composed of only a (meth) acryloyl group or an atom selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom as a polymerizable group; A compound having a weight average molecular weight of 1000 or less and having 3 or more polymerizable groups in the molecule.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.

Hereinafter, the antireflection film of this embodiment will be described in detail.

An example of a preferred embodiment of the antireflection film of this aspect is shown in FIG.
The antireflection film 10 in FIG. 1 has a base material 1 and an antireflection layer 2. The antireflection layer 2 has a moth-eye structure having a concavo-convex shape formed by metal oxide particles 3 on the surface opposite to the interface on the substrate 1 side.
The antireflection layer 2 includes metal oxide particles 3 and a binder resin 4.

(Moth eye structure)
The antireflection layer provided on one side or both sides of the base material of the antireflection film of this embodiment has a moth-eye structure having an uneven shape formed by the metal oxide particles of (A).
Here, the moth-eye structure is a processed surface of a substance (material) for suppressing light reflection, and refers to a structure having a periodic fine structure pattern. In particular, for the purpose of suppressing the reflection of visible light, it refers to a structure having a fine structure pattern with a period of less than 780 nm. It is preferable that the period of the fine structure pattern is less than 380 nm because the color of the reflected light is eliminated. A period of 100 nm or more is preferable because light with a wavelength of 380 nm can recognize a fine structure pattern and is excellent in antireflection properties. The presence or absence of the moth-eye structure can be confirmed by observing the surface shape with a scanning electron microscope (SEM), an atomic force microscope (AFM), or the like, and examining whether the fine structure pattern is formed.

The concavo-convex shape of the antireflection layer of the antireflection film of this aspect is B / A, which is a ratio of the distance A between the apexes of the adjacent convex portions and the distance B between the center and the concave portion between the apexes of the adjacent convex portions. Is 0.5 or more. When B / A is 0.5 or more, the depth of the concave portion increases with respect to the distance between the convex portions, and a refractive index gradient layer in which the refractive index changes more gradually from the air to the inside of the antireflection layer is formed. Therefore, the reflectance can be reduced.
B / A can be controlled by the volume ratio of the binder resin and the metal oxide particles in the antireflection layer after curing. Therefore, it is important to appropriately design the blending ratio between the binder resin and the metal oxide particles. Further, the volume ratio of the binder resin and the metal oxide particles in the antireflection layer is increased in the composition for forming the antireflection layer by allowing the binder resin to permeate the substrate or volatilize in the process of producing the moth-eye structure. Therefore, it is also important to set the matching with the base material appropriately.
Furthermore, in order to make B / A 0.5 or more and reduce the reflectance, it is preferable that the metal oxide particles forming the convex portions are uniformly spread with a high filling rate. In addition, it is important that the filling rate is not too high. If the filling rate is too high, adjacent particles come into contact with each other and the B / A of the concavo-convex structure is reduced. From the above viewpoint, it is preferable that the content of the metal oxide particles forming the convex portion is adjusted so as to be uniform throughout the antireflection layer. The filling rate can be measured as the area occupancy of particles located on the most surface side when observing metal oxide particles that form convex portions from the surface by SEM or the like, and is preferably 30% to 95%. It is more preferably 90%, more preferably 50-85%.

A method for measuring B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the center between the apexes of adjacent convex portions and the concave portion, will be described in more detail below.
B / A can be measured by cross-sectional SEM observation of the antireflection film. The antireflection film sample is cut with a microtome to obtain a cross section, and SEM observation is performed at an appropriate magnification (about 5000 times). For easy observation, the sample may be subjected to appropriate processing such as carbon deposition and etching. B / A is the distance between the vertices of adjacent protrusions at the interface between the air and the sample, and the vertices of adjacent protrusions in the plane perpendicular to the substrate surface including the vertices of the adjacent protrusions. The distance between the straight line connecting the two and the vertical bisector reaching the particle or the binder resin is defined as B, and when 100 points are measured, the average value of B / A is calculated.
In the SEM photograph, there are cases where the distance A between the vertices of the adjacent convex portions and the distance B between the vertices of the adjacent convex portions and the concave portion B cannot be measured accurately with respect to all the projected and recessed portions. However, in that case, the length may be measured by paying attention to the convex portion and the concave portion shown on the near side in the SEM image.
Note that the concave portion needs to be measured at the same depth as the particles forming the two adjacent convex portions to be measured in the SEM image. This is because if the distance to a particle or the like reflected on the near side is measured as B, B may be estimated small.

B / A is preferably 0.6 or more, more preferably 0.7 or more, and still more preferably 0.8 or more. Moreover, from the viewpoint that the moth-eye structure can be firmly fixed and has excellent scratch resistance, it is preferably 0.9 or less.

(Metal oxide particles)
The metal oxide particles forming the moth-eye structure of the antireflection layer will be described.
The metal oxide particles (A) contained in the composition for forming an antireflection layer are metal oxide particles having an average primary particle size having a hydroxyl group on the surface of 50 nm to 380 nm.
In the completed antireflection layer, the hydroxyl group on the surface of the metal oxide particle (A) is a hydroxyl group (silanol group) directly bonded to a silicon atom of the compound (C) or a hydrolyzed bond directly bonded to a silicon atom. A part or all of the decomposable group may disappear due to a condensation reaction with a silanol group formed by hydrolysis. Since the metal oxide particles are strongly bonded to the compound (C) by this condensation reaction, it is preferable because the metal oxide particles are more difficult to fall off even when a strong stress is applied.

The average primary particle size of the metal oxide particles (A) is from 50 nm to 380 nm, preferably from 100 nm to 320 nm, and more preferably from 120 nm to 250 nm. It is preferable that the average primary particle diameter of the metal oxide particles is 50 nm or more because aggregation of the particles can be suppressed. Further, from the viewpoint of haze suppression, it is preferably 380 nm or less, more preferably 300 nm or less, and particularly preferably 220 nm or less.
The average primary particle size of the metal oxide particles refers to the 50% cumulative particle size of the volume average particle size. When measuring the average primary particle diameter of the metal oxide particles contained in the antireflection layer, it can be measured by an electron micrograph. For example, a section TEM image of the antireflection film is taken, the diameter of each of the 100 primary particles is measured to calculate the volume, and the 50% cumulative particle size of the volume average particle size is defined as the average primary particle size. be able to. When the particle is not a spherical diameter, the average value of the major axis and the minor axis is regarded as the diameter of the primary particle.

In this embodiment, the amount of hydroxyl groups on the particle surface is defined as follows. The amount of hydroxyl groups is measured by solid ²⁹ Si NMR ( ²⁹ Si CP / MAS). Although the metal element M on the surface of the metal oxide particle is bonded to n hydroxyl groups, the amount of hydroxyl group on the particle surface is Qn × n ÷ (particle radius (unit: nm ) Squared). For example, when the particle is silica (with a particle radius R), silicon bonded to 4 neutral oxygen atoms (signal intensity Q0), silicon bonded to 3 neutral oxygen atoms and one hydroxyl group (signal intensity Q1) , there silicon bonded to two neutral oxygen 2 atoms and hydroxyl groups (signal intensity Q2) is, the particle surface hydroxyl group content is (Q1 × 1 + Q2 × 2 ) ÷ R 2. In the case of silica, the signal giving a signal intensity Q2 has a chemical shift of −91 to −94 ppm, the signal giving a signal intensity Q1 has a chemical shift of −100 to −102 ppm, and the signal giving a signal intensity Q0 has a chemical shift of −109 to −111 ppm.
The more hydroxyl groups on the surface, the greater the amount of reaction, which is preferable. 1.00 × 10 ⁻⁴ to 4.00 × 10 ⁻¹ is preferable, 5.00 × 10 ⁻⁴ to 3.50 × 10 ⁻¹ is more preferable, and 1.00 × 10 ⁻³ to 3.00 × 10 ^-1 is more preferred.

The metal oxide particles (A) are preferably metal oxide particles that are surface-modified with a compound having a (meth) acryloyl group. This preferred embodiment is referred to as the first embodiment. The compound having a (meth) acryloyl group is preferably a silane coupling agent having a (meth) acryloyl group. The surface treatment is preferably a silane coupling treatment.
By using metal oxide particles surface-modified with a compound having a (meth) acryloyl group, the (meth) acryloyl group of the compound (C) and the (meth) acryloyl group of the compound (B) are cross-linked. Since the metal oxide particles are firmly fixed to the binder resin and the pencil hardness of the resulting moth-eye structure is higher, and even when a strong stress is applied, the metal oxide particles are more difficult to drop off, which is preferable.
For specific examples of the surface treatment method and preferred examples thereof, reference can be made to the descriptions in [0119] to [0147] of JP-A-2007-298974.
In 1st aspect, it is preferable that content of (C) is 0.01 or more and 6.0 or less by mass ratio with respect to content of (A).

In the antireflection layer forming composition, an embodiment in which the metal oxide particles (A) are surface-modified with the compound (C) is also preferable. This preferred embodiment is referred to as the second embodiment. According to this aspect, as described above, the hydroxyl group on the surface of the metal oxide particle (A) is directly bonded to the hydroxyl group (silanol group) or silicon atom directly bonded to the silicon atom of the compound (C). When the hydrolyzable group undergoes a condensation reaction with a silanol group formed by hydrolysis, the metal oxide particles are firmly bonded to the compound (C). Further, since the (meth) acryloyl group of the compound (C) modified on the surface of the metal oxide particle (A) is cross-linked with the (meth) acryloyl group of the compound (B), the metal oxide particles are bonded to the binder. The pencil hardness of the resulting moth-eye structure is firmly fixed to the resin, and even after the pencil hardness test, the metal oxide particles fall off more even after confirming the adhesion of the particles after applying stress such as rubbing with an eraser. Since it becomes difficult, it is preferable. Further, the second aspect has an advantage that the same effect can be obtained by using a small amount of the compound (C) as compared with the first aspect.
In 2nd aspect, it is preferable that content of (C) modified on the surface of (A) is 0.001 or more and 0.3 or less by mass ratio with respect to content of (A).

Examples of the metal oxide particles include silica particles, titania particles, zirconia particles, and antimony pentoxide particles. From the viewpoint that moth-eye structures are easily formed because haze is hardly generated because the refractive index is close to that of many binders. Silica particles are preferred.

The metal oxide particles are particularly preferably calcined silica particles.
The calcined silica particles are manufactured by a known technique in which silica particles are obtained by hydrolyzing and condensing a hydrolyzable silicon compound in an organic solvent containing water and a catalyst, and then the silica particles are calcined. For example, Japanese Patent Application Laid-Open Nos. 2003-176121 and 2008-137854 can be referred to.
Although it does not specifically limit as a raw material silicon compound which manufactures a burning silica particle, Chlorosilanes, such as tetrachlorosilane, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, methylvinyldichlorosilane, trimethylchlorosilane, methyldiphenylchlorosilane Compound: Tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, trimethoxyvinylsilane, triethoxyvinylsilane, 3-glycidoxypropyltrimethoxysilane, 3-chloro Propyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxy Silane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-chloropropylmethyldimethoxysilane, Alkoxysilane compounds such as diphenyldimethoxysilane, diphenyldiethoxysilane, dimethoxydiethoxysilane, trimethylmethoxysilane, trimethylethoxysilane; tetraacetoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, diphenyldiacetoxysilane Acyloxysilane compounds such as trimethylacetoxysilane; dimethylsilanediol, diphenylsilanediol, tri Silanol compounds such as chill silanol; and the like. Of the above-exemplified silane compounds, the alkoxysilane compound is particularly preferred because it is more easily available and the resulting fired silica particles do not contain halogen atoms as impurities. As a preferable form of the baked silica particles according to this embodiment, it is preferable that the halogen atom content is substantially 0% and no halogen atom is detected.
The firing temperature is not particularly limited, but is preferably 800 to 1300 ° C, and more preferably 1000 to 1200 ° C.

The shape of the metal oxide particles is most preferably spherical, but there is no problem even if the shape is not spherical such as indefinite.
The silica particles may be either crystalline or amorphous.
The metal oxide particles may be used by firing commercially available particles. Specific examples include IPA-ST-L (average primary particle size 50 nm, silica sol manufactured by Nissan Chemical Industries, Ltd.), IPA-ST-ZL (average primary particle size 80 nm, silica sol manufactured by Nissan Chemical Industries, Ltd.) , Snowtex MP-1040 (average primary particle size 100 nm, silica manufactured by Nissan Chemical Industries, Ltd.), Snowtex MP-2040 (average primary particle size 200 nm, silica manufactured by Nissan Chemical Industries, Ltd.), Seahoster KE-P10 ( Average primary particle size 150 nm, Nippon Silica Co., Ltd. amorphous silica), Seahoster KE-P20 (average primary particle size 200 nm, Nippon Shokubai Co., Ltd. amorphous silica), ASFP-20 (average primary particle size 200 nm, Nippon Electrochemical) (Alumina manufactured by Kogyo Co., Ltd.) and the like can be preferably used. Furthermore, as long as the requirements of the present application are satisfied, commercially available particles may be used as they are.

The content of the metal oxide particles (A) with respect to the total solid content in the composition for forming an antireflection layer is preferably 10% by mass to 95% by mass, more preferably 35% by mass to 90% by mass, and more preferably 65% by mass. % To 85% by mass is more preferable.

(Binder resin)
The binder resin for the antireflection layer will be described.
The binder resin of the antireflection layer contains at least one of a structure derived from the following (B) and a structure derived from the following (C) in the composition for forming an antireflection layer.
(B) having a polymerizable group other than a (meth) acryloyl group composed of only a (meth) acryloyl group or an atom selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom as a polymerizable group; A compound having a weight average molecular weight of 1000 or less and having 3 or more polymerizable groups in the molecule.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.
Here, the structure derived from (B) is a structure obtained by the reaction of the polymerizable group of compound (B), and the structure derived from (C) is the (meth) acryloyl of compound (C). It is a structure obtained by reacting at least one of a group, a hydroxyl group and a hydrolyzable group.

<Compound (B)>
The compound (B) contained in the composition for forming an antireflection layer will be described.
Compound (B) has a polymerizable group other than a (meth) acryloyl group or a (meth) acryloyl group composed only of an atom selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom as a polymerizable group. And a compound having 3 or more polymerizable groups in one molecule and having a weight average molecular weight of 1000 or less.
Specific examples of the polymerizable group other than the (meth) acryloyl group composed only of an atom selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom include any of the following formulas (Q-1) to (Q-14): The group represented by these is mentioned, However, It is not limited to these.

The polymerizable group possessed by the compound (B) is preferably a (meth) acryloyl group.

The compound (B) preferably has 3.0 or more polymerizable groups in one molecule, more preferably 4.0 or more, and still more preferably 5.0 or more.
Specific examples of the compound (B) include alkylene glycol (meth) acrylic acid esters, polyoxyalkylene glycol (meth) acrylic acid diesters, alcohol (meth) acrylic acid esters, ethylene oxide or propylene oxide adducts. (Meth) acrylic acid esters, epoxy (meth) acrylates, urethane (meth) acrylates, polyester (meth) acrylates, and the like.

Among them, esters of alcohol and (meth) acrylic acid are preferable, and esters of polyhydric alcohol and (meth) acrylic acid are particularly preferable. For example, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO modified trimethylolpropane tri (meth) acrylate, PO modified trimethylolpropane tri (meth) acrylate, EO Modified tri (meth) acrylate phosphate, trimethylolethane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa ( (Meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, urethane acrylate Polyester polyacrylate and caprolactone-modified tris (acryloyloxyethyl) isocyanurate.

The weight average molecular weight of the compound (B) is 1000 or less, preferably 100 or more and 800 or less, and more preferably 200 or more and 700 or less. When the weight average molecular weight of the compound (B) is 1000 or less, the crosslinking density can be increased, which is preferable from the viewpoint of hardness.
The weight average molecular weight is a value expressed in terms of polystyrene by detection with a solvent THF (tetrahydrofuran) and a differential refractometer by GPC (gel permeation chromatography) measured under the following conditions using the following apparatus and column.
[Device name] TOSOH HLC-8220GPC
[Column] TOSOH TSKgel Super HZM-H
Three (4.6 mm x 15 cm) are connected and used.
[Column temperature] 25 ° C
[Sample concentration] 0.1% by mass
[Flow rate] 0.35 ml / min
[Calibration curve] TSK standard polystyrene manufactured by TOSOH Mw = 2800000-1050 calibration curves with 7 samples are used.

The content of (B) with respect to the total solid content in the composition for forming an antireflection layer is preferably 1.0% by mass or more and 70.0% by mass or less, more preferably 2.5% by mass or more and 42.0% by mass or less. Preferably, it is more preferably 6.0% by mass or more and 20.0% by mass or less.

<Compound (C)>
The compound (C) contained in the composition for forming an antireflection layer will be described.
The compound (C) is a compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.

The hydrolyzable group of the compound (C) is preferably an alkoxy group, preferably an alkoxy group having 1 to 3 carbon atoms, and most preferably a methoxy group.

From the viewpoint that both the (meth) acryloyl group, the hydroxyl group and the hydrolyzable group in the same molecule easily react, the compound (C) contains a carbon atom constituting a carbonyl group in the (meth) acryloyl group, a hydroxyl group A compound having 4 or more carbon atoms between a silicon atom to which at least one of a group and a hydrolyzable group is directly bonded is preferable.
In the compound (C), the number of carbon atoms between the carbon atom constituting the carbonyl group in the (meth) acryloyl group and the silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded is 4 It is more preferably 12 or less and further preferably 6 or more and 10 or less.
Specific examples of such compounds include the following.

From the viewpoint of reacting one or more (meth) acryloyl groups in one molecule with the compound (B), the number of silicon atoms to which at least one of the hydroxyl group and the hydrolyzable group of the compound (C) is directly bonded ( The ratio of the number of (meth) acryloyl groups is preferably 1.1 or more and 3.0 or less.
Specific examples of such compounds include the following.

From the viewpoint of ensuring the film strength of the binder, the compound (C) is a silicon atom in which a carbon atom constituting a carbonyl group in a (meth) acryloyl group is directly bonded to at least one of a hydroxyl group and a hydrolyzable group. It is preferable that it is a compound which has a urethane bond between these.
Specific examples of such compounds include the following.

The weight average molecular weight of the compound (C) is from 300 to 1,000, preferably from 300 to 800, and more preferably from 300 to 600. When the weight average molecular weight of the compound (C) is 300 or more and 1000 or less, both the (meth) acryloyl group, the hydroxyl group and the hydrolyzable group in the same molecule are easily reacted, and a moth-eye shape is easily obtained. preferable.
The weight average molecular weight is a value expressed in terms of polystyrene by detection with a solvent THF (tetrahydrofuran) and a differential refractometer by GPC (gel permeation chromatography) measured under the following conditions using the following apparatus and column.
[Device name] TOSOH HLC-8220GPC
[Column] TOSOH TSKgel Super HZM-H
Three (4.6 mm x 15 cm) are connected and used.
[Column temperature] 25 ° C
[Sample concentration] 0.1% by mass
[Flow rate] 0.35 ml / min
[Calibration curve] TSK standard polystyrene manufactured by TOSOH Mw = 2800000-1050 calibration curves with 7 samples are used.

The number of (meth) acryloyl groups in the compound (C) is preferably 1 to 8 and more preferably 2 to 4 in one molecule.

The content of (C) with respect to the total solid content in the composition for forming an antireflection layer is preferably 1.0% by mass or more and 70.0% by mass or less, more preferably 2.5% by mass or more and 42.0% by mass or less. Preferably, it is more preferably 6.0% by mass or more and 20.0% by mass or less.

Although the specific example of a compound (C) is also shown below, this aspect is not limited to these.

From the viewpoint of firmly adhering the particle-binder and ensuring the binder strength, in the case of the second embodiment described above and other than the embodiment not including (C) as the binder resin forming compound, The mass ratio of the content of (C) to the sum of the content and the content of (C) is preferably 0.1 or more and 0.9 or less, and more preferably 0.2 or more and 0.8 or less. And more preferably 0.3 or more and 0.7 or less, and particularly preferably 0.4 or more and 0.6 or less.

(Base material)
The base material in the antireflection film of this embodiment is not particularly limited as long as it is a base material having translucency generally used as the base material of the antireflection film, but a plastic base material or a glass base material is preferable.
Various plastic substrates can be used, such as cellulose resin; cellulose acylate (triacetate cellulose, diacetyl cellulose, acetate butyrate cellulose), polyester resin; polyethylene terephthalate, (meth) acrylic resin, polyurethane, etc. Base materials containing polycarbonate resins, polycarbonates, polystyrenes, olefin resins, etc., preferably cellulose acylates, polyethylene terephthalates, or substrates containing (meth) acrylic resins, and substrates containing cellulose acylates Is more preferable. As the cellulose acylate, the base material described in JP 2012-093723 A can be preferably used.
The thickness of the plastic substrate is usually about 10 μm to 1000 μm, but is preferably 20 μm to 200 μm, and preferably 25 μm to 100 μm from the viewpoints of good handleability, high translucency, and sufficient strength. More preferred. As a light-transmitting property of the plastic substrate, a material having a visible light transmittance of 90% or more is preferable.

(Other functional layers)
The antireflection film of this embodiment may have a functional layer other than the antireflection layer.
For example, the aspect which has a hard-coat layer between a base material and an antireflection layer is mentioned preferably. Further, an easy adhesion layer for imparting adhesion, a layer for imparting antistatic properties, or the like may be provided, or a plurality of these may be provided.

[Method for producing antireflection film]
Although the manufacturing method of the antireflection film of this aspect is not specifically limited, From the viewpoint of production efficiency, a manufacturing method using a coating method is preferable.
That is, the manufacturing method of the antireflection film is:
A method for producing an antireflection film having a substrate and an antireflection layer,
The antireflection layer has a moth-eye structure having a concavo-convex shape formed by the metal oxide particles of the following (A) on the surface opposite to the interface on the substrate side,
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. And
The antireflection film which has the process of apply | coating the composition for antireflection layer containing the following (A), (B) and (C) on the said base material, and hardening the following (B) and (C) It is a manufacturing method.
(A) Metal oxide particles having a hydroxyl group on the surface and an average primary particle size of 50 nm or more and 380 nm or less.
(B) A compound having three or more (meth) acryloyl groups in one molecule and having a weight average molecular weight of 1,000 or less. However, when the compound (B) has a polymerizable group other than the (meth) acryloyl group, the polymerizable group is a polymerization composed only of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom. Sex group.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.

The composition for forming an antireflection layer may contain a solvent, a polymerization initiator, a metal complex compound, a particle dispersant, a leveling agent, an antifouling agent, and the like.
A solvent having a polarity close to that of the fine particles is preferably selected from the viewpoint of improving dispersibility. Specifically, for example, when the fine particles are metal oxide particles, an alcohol solvent is preferable, and examples thereof include methanol, ethanol, 2-propanol, 1-propanol, and butanol. For example, when the fine particles are metal resin particles having a hydrophobic surface modified, ketone-based, ester-based, carbonate-based, alkane, aromatic-based solvents are preferable, and methyl ethyl ketone (MEK), dimethyl carbonate, methyl acetate are preferable. , Acetone, methylene chloride, cyclohexanone and the like. These solvents may be used in a mixture of a plurality of types as long as the dispersibility is not significantly deteriorated.
The particle dispersing agent can facilitate uniform arrangement of the particles by reducing the cohesive force between the particles. The dispersant is not particularly limited, but is preferably an anionic compound such as a sulfate or phosphate, a cationic compound such as an aliphatic amine salt or a quaternary ammonium salt, a nonionic compound or a polymer compound. And a steric repulsion group are more preferred because they have a high degree of freedom in selection. A commercial item can also be used as a dispersing agent. For example, BYK Japan made of (stock) DISPERBYK160, DISPERBYK161, DISPERBYK162, DISPERBYK163, DISPERBYK164, DISPERBYK166, DISPERBYK167, DISPERBYK171, DISPERBYK180, DISPERBYK182, DISPERBYK2000, DISPERBYK2001, DISPERBYK2164, Bykumen, BYK-P104, BYK-P104S, BYK-220S, Anti-Terra 203, Anti-Terra 204, Anti-Terra 205 (named above) are listed.
By reducing the surface tension of the coating solution, the leveling agent can stabilize the solution after coating and facilitate the uniform arrangement of particles and binder resin. For example, the compounds described in JP-A-2004-331812 and JP-A-2004-163610 can be used.
The antifouling agent can suppress adhesion of dirt and fingerprints by imparting water and oil repellency to the moth-eye structure. For example, compounds described in JP 2012-88699 A can be used.
By adding the metal complex compound, hydrolysis of the compound (C) can be promoted and the reactivity can be increased. The metal complex compound is not particularly limited as long as it contains a metal atom and a ligand coordinated thereto, and can be appropriately selected depending on the purpose. For example, di-n-propoxy bis (acetyl) Acetonato) zirconium, di-iso-propoxy bis (acetylacetonato) zirconium, di-n-butoxy bis (acetylacetonato) zirconium, di-tert-butoxy bis (acetylacetonato) zirconium, mono-n -Propoxy tris (acetylacetonate) zirconium, mono-iso-propoxy tris (acetylacetonate) zirconium, mono-n-butoxy tris (acetylacetonate) zirconium, mono-tert-butoxy tris (acetylacetonate) ) Zirconium, zirconi Mutaacetylacetonate, di-n-propoxy bis (ethyl acetoacetate) zirconium, di-iso-propoxy bis (ethyl acetoacetate) zirconium, di-n-butoxy bis (ethyl acetoacetate) zirconium, di- tert-butoxy bis (ethyl acetoacetate) zirconium, mono-n-propoxy tris (ethyl acetoacetate) zirconium, mono-iso-propoxy tris (ethyl acetoacetate) zirconium, mono-n-butoxy tris (ethyl acetoacetate) Acetate) zirconium, mono-tert-butoxy-tris (ethylacetoacetate) zirconium, zirconium tetraethylacetoacetate, mono (acetylacetonato) tris (ethylacetoacetate) ) Zirconium, bis (acetylacetonato) bis (ethylacetoacetate) zirconium, tris (acetylacetonato) mono (ethylacetoacetate) zirconium, di-n-propoxy mono (acetylacetonato) aluminum, di-iso -Propoxy mono (acetylacetonato) aluminum, di-n-butoxy mono (acetylacetonato) aluminum, di-tert-butoxy mono (acetylacetonato) aluminum, mono-n-propoxybis (acetylacetonate) ) Aluminum, mono-iso-propoxy bis (acetylacetonate) aluminum, mono-n-butoxy bis (acetylacetonate) aluminum, mono-tert-butoxy bis (acetylacetonate) ) Aluminum, aluminum trisacetylacetonate, di-n-propoxy mono (ethyl acetoacetate) aluminum, di-iso-propoxy mono (ethyl acetoacetate) aluminum, di-n-butoxy mono (ethyl acetoacetate) aluminum , Di-tert-butoxy mono (ethyl acetoacetate) aluminum, mono-n-propoxy bis (ethyl acetoacetate) aluminum, mono-iso-propoxy bis (ethyl acetoacetate) aluminum, mono-n-butoxy bis (Ethyl acetoacetate) aluminum, mono-tert-butoxy bis (ethyl acetoacetate) aluminum, aluminum trisethyl acetoacetate, mono (acetylacetonate) bis (d Le acetoacetate) aluminum, bis (acetylacetonate) mono (ethylacetoacetate) and aluminum. These may be used alone or in combination of two or more.

(Polymerization initiator)
The composition for forming an antireflection layer preferably contains a polymerization initiator, and more preferably contains a photopolymerization initiator.
As photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, Examples include fluoroamine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, and coumarins. Specific examples, preferred embodiments, commercially available products, and the like of the photopolymerization initiator are described in paragraphs [0133] to [0151] of JP-A-2009-098658, and can be suitably used in this embodiment as well. it can.
“Latest UV Curing Technology” {Technical Information Association, Inc.} (1991), p. 159, and “UV Curing System” written by Kiyomi Kato (published by the General Technology Center in 1989), p. Various examples are also described in 65 to 148 and are useful in this embodiment.

The application method of the composition for forming an antireflection layer is not particularly limited, and a known method can be used. Examples include dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, and die coating.

From the viewpoint of easy application uniformly, the solid content concentration of the composition for forming an antireflection layer is preferably 10% by mass or more and 80% by mass or less, and more preferably 20% by mass or more and 60% by mass or less.

[Polarizer]
The polarizing plate of this embodiment is a polarizing plate having a polarizer and at least one protective film for protecting the polarizer, and at least one of the protective films is the antireflection film of this embodiment.

Polarizers include iodine-based polarizing films, dye-based polarizing films using dichroic dyes, and polyene-based polarizing films. The iodine-based polarizing film and the dye-based polarizing film can be generally produced using a polyvinyl alcohol film.

[cover glass]
The cover glass of this embodiment has the antireflection film of this embodiment as a protective film. The base material of the antireflection film may be made of glass, or an antireflection film having a plastic film base material may be pasted on a glass support.

[Image display device]
The image display apparatus of this aspect has the antireflection film or polarizing plate of this aspect.
The antireflection film and polarizing plate of this embodiment are suitably used for image display devices such as liquid crystal display devices (LCD), plasma display panels (PDP), electroluminescence displays (ELD), and cathode ray tube display devices (CRT). In particular, a liquid crystal display device is preferable.
In general, a liquid crystal display device has a liquid crystal cell and two polarizing plates arranged on both sides thereof, and the liquid crystal cell carries a liquid crystal between two electrode substrates. Furthermore, one optically anisotropic layer may be disposed between the liquid crystal cell and one polarizing plate, or two optically anisotropic layers may be disposed between the liquid crystal cell and both polarizing plates. The liquid crystal cell is preferably in TN mode, VA mode, OCB mode, IPS mode or ECB mode.

<Second embodiment of the present invention>
[Antireflection film]
The antireflection film of the second aspect of the present invention is
An antireflection film comprising a base material, an antireflection layer containing a binder resin and metal oxide particles having an average primary particle size of 50 nm to 250 nm,
The surface of the metal oxide particles has a hydroxyl group amount of 1.00 × 10 ⁻¹ or less,
The indentation hardness of the metal oxide particles is 400 MPa or more,
The binder resin is a resin having a hydroxyl group,
The antireflection layer is an antireflection film having a moth-eye structure having a concavo-convex shape formed of metal oxide particles on the surface opposite to the interface on the substrate side.

An example of a preferred embodiment of the antireflection film of this aspect is shown in FIG.
The antireflection film 10 in FIG. 1 has a base material 1 and an antireflection layer 2. The antireflection layer 2 has a moth-eye structure having a concavo-convex shape formed by metal oxide particles 3 on the surface opposite to the substrate 1.
The antireflection layer 2 includes metal oxide particles 3 and a binder resin 4.

(Moth eye structure)
The surface of the antireflection layer opposite to the base material has a moth-eye structure having a concavo-convex shape formed by metal oxide particles.
Here, the moth-eye structure refers to a processed surface of a substance (material) for suppressing light reflection, and a structure having a periodic fine structure pattern. In particular, for the purpose of suppressing the reflection of visible light, it refers to a structure having a fine structure pattern with a period of less than 780 nm. It is preferable that the period of the fine structure pattern is less than 380 nm because the color of the reflected light is eliminated. A period of 100 nm or more is preferable because light with a wavelength of 380 nm can recognize a fine structure pattern and is excellent in antireflection properties. The presence or absence of the moth-eye structure can be confirmed by observing the surface shape with a scanning electron microscope (SEM), an atomic force microscope (AFM), or the like, and examining whether the fine structure pattern is formed.

The concavo-convex shape of the antireflection layer of the antireflection film of this aspect is B / A, which is a ratio of the distance A between the apexes of the adjacent convex portions and the distance B between the center and the concave portion between the apexes of the adjacent convex portions. Is preferably 0.5 or more. When B / A is 0.5 or more, the depth of the concave portion increases with respect to the distance between the convex portions, and a refractive index gradient layer in which the refractive index changes more gradually from the air to the inside of the antireflection layer is formed. Therefore, the reflectance can be further reduced.
B / A can be controlled by the volume ratio of the binder resin and the metal oxide particles in the antireflection layer after curing. Therefore, it is important to appropriately design the blending ratio between the binder resin and the metal oxide particles. Further, the volume ratio of the binder resin and the metal oxide particles in the antireflection layer is increased in the composition for forming the antireflection layer by allowing the binder resin to permeate the substrate or volatilize in the process of producing the moth-eye structure. Therefore, it is also important to set the matching with the base material appropriately.
Furthermore, in order to make B / A 0.5 or more and reduce the reflectance, it is preferable that the metal oxide particles forming the convex portions are uniformly spread with a high filling rate. In addition, it is important that the filling rate is not too high. If the filling rate is too high, adjacent particles come into contact with each other and the B / A of the concavo-convex structure is reduced. From the above viewpoint, it is preferable that the content of the metal oxide particles forming the convex portion is adjusted so as to be uniform throughout the antireflection layer. The filling rate can be measured as the area occupancy of particles located on the most surface side when observing metal oxide particles that form convex portions from the surface by SEM or the like, and is preferably 30% to 95%. It is more preferably 90%, more preferably 50-85%.
When particles with a small amount of hydroxyl groups on the surface, such as baked silica particles, are used as the metal oxide particles, the dispersibility of the particles in the binder resin when a resin having no hydroxyl groups is used as the binder resin for the antireflection layer. It can be presumed that the phenomenon in which the particles are aggregated in the binder resin and the reflectance is increased due to the decrease in B / A due to the contact between adjacent particles. At this time, B / A can be increased by using the resin having a hydroxyl group in this embodiment as the binder resin.

B / A is preferably 0.5 or more, more preferably 0.6 or more, and further preferably 0.7 or more. Moreover, from the viewpoint that the moth-eye structure can be firmly fixed and has excellent scratch resistance, it is preferably 0.9 or less.

In order to reduce the reflectance, it is preferable that the metal oxide particles are uniformly spread with a high filling rate. It is also important that the filling rate is not too high. If the filling rate is too high, adjacent particles come into contact with each other to reduce the uneven B / A, resulting in an increase in reflectance.
From the above viewpoint, the content of the metal oxide particles is preferably adjusted to be uniform throughout the antireflection layer. The filling factor can be measured as the area occupancy of the particles located on the most surface side when the metal oxide particles are observed from the surface by SEM or the like. The filling rate is preferably 30% to 95%, more preferably 40 to 90%, and still more preferably 50 to 85%.

(Metal oxide particles)
The metal oxide particles forming the moth-eye structure of the antireflection layer will be described.
The metal oxide particles have an average primary particle size of 50 nm or more and 250 nm or less, a surface hydroxyl group content of 1.00 × 10 ⁻¹ or less, and an indentation hardness of 400 MPa or more.

As the metal oxide particles, metal oxide particles having an average primary particle size of 50 nm or more and 250 nm or less and a dispersion degree Cv value of the average primary particle size of 10% or less can be preferably used. The degree of dispersion Cv value is a value (unit:%) that can be calculated by Cv value = ([standard deviation of average primary particle size] / [average average particle size]) × 100 (1) (small). This means that the average primary particle size is uniform. The average primary particle size is measured using a scanning electron microscope (SEM). The average particle diameter of the metal oxide particles and the standard deviation thereof are calculated based on the measured values of the particle diameters of 200 or more metal oxide particles. In addition, the average particle diameter here means the maximum diameter of a circumscribed circle when the particles are not spherical. Also in the case of a mixture of a plurality of types of particles having different average primary particle sizes, the Cv value as a whole particle is calculated.
When the average primary particle size is 50 nm or more, it can function as an antireflection layer having a moth-eye structure, and when it is 250 nm or less, Bragg diffraction due to regular arrangement of metal oxide particles hardly occurs in the visible light region. The color development (coloring) phenomenon derived from this is not shown. Therefore, it is preferable that the Cv value is small because particle aggregation is less likely to occur and an antireflection layer having a low reflectance and a high transmittance can be formed without coloring. The average primary particle size is preferably from 100 nm to 220 nm, and more preferably from 120 nm to 200 nm. The Cv value is preferably 1 to 10%, more preferably 1 to 5%.
From the reason that the Cv value can be reduced, the metal oxide particles preferably contain only metal oxide particles having a primary particle size of 50 nm to 250 nm, and only metal oxide particles having a primary particle size of 100 nm to 220 nm. It is more preferable to contain only metal oxide particles having a primary particle size of 120 nm to 200 nm.

In another aspect, the metal oxide fine particles preferably include both metal oxide fine particles having an average primary particle size of 120 nm or more and 250 nm or less and metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm. In this case, particles having a larger particle size mainly contribute to the moth-eye structure, and particles having a smaller particle size are mixed between the large particles, thereby suppressing aggregation of the large particles. As a result, B / A May be increased, and the reflectance and haze may be improved.
Since metal oxide particles having a primary particle size of 50 nm or more and less than 120 nm are more immersed in the binder, the convex portion as the antireflection layer is formed by metal oxide fine particles having a primary particle size of 120 nm or more and 200 nm or less. Point to.
The frequency of metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm with respect to metal oxide fine particles having an average primary particle size of 120 nm or more and 250 nm or less is preferably 2 to 5 times higher. By setting this range, the aggregation suppressing effect is high and the reflectance can be lowered. The metal oxide particles having an average primary particle size of 50 nm or more are preferably an average primary particle size of 75 nm or more and 110 nm or less because the reflectance can be particularly lowered.
When metal oxide particles having different average primary particle sizes are used in combination, it is preferable to make the hydroxyl group amounts on the surfaces of both particles close to each other because aggregation is less likely.
However, since the metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm are mainly used for inhibiting the aggregation of metal oxide particles having an average primary particle size of 120 nm or more and 250 nm or less and separating them, they are available. Metal oxide particles having an easy hydroxyl group amount of more than 1.00 × 10 ⁻¹ or an indentation hardness of less than 400 MPa may be used.

The average primary particle size of the metal oxide particles refers to a cumulative 50% particle size of the volume average particle size. When measuring the average primary particle diameter of the metal oxide particles contained in the antireflection layer, it can be measured by an electron micrograph. For example, the antireflection film is observed from the surface side by SEM observation at an appropriate magnification (about 5000 times), the diameter of each of the 100 primary particles is measured, the volume is calculated, and the cumulative 50% particle size is calculated. The average primary particle size can be obtained. When the particles are not spherical, the average value of the major and minor diameters is regarded as the diameter of the primary particles. At this time, for easy observation, the sample may be appropriately subjected to carbon deposition, etching, or the like.

In this embodiment, the amount of hydroxyl groups on the particle surface is defined as follows. The amount of hydroxyl groups is measured by solid ²⁹ Si NMR ( ²⁹ Si CP / MAS). Although the metal element M on the surface of the metal oxide fine particle is bonded to n hydroxyl groups, and the signal intensity is defined as Qn, the amount of hydroxyl groups on the particle surface is as follows: Qn × n ÷ (particle radius (unit: nm :) squared). For example, when the particle is silica (with a particle radius R), silicon bonded to 4 neutral oxygen atoms (signal intensity Q0), silicon bonded to 3 neutral oxygen atoms and one hydroxyl group (signal intensity Q1) , there silicon bonded to two neutral oxygen 2 atoms and hydroxyl groups (signal intensity Q2) is, the particle surface hydroxyl group content is (Q1 × 1 + Q2 × 2 ) ÷ R 2. In the case of silica, the signal giving a signal intensity Q2 has a chemical shift of −91 to −94 ppm, the signal giving a signal intensity Q1 has a chemical shift of −100 to −102 ppm, and the signal giving a signal intensity Q0 has a chemical shift of −109 to −111 ppm.

The amount of hydroxyl groups on the particle surface becomes smaller as it becomes harder by firing, and is preferably 1.00 × 10 ⁻⁵ to 1.00 × 10 ^−1, more preferably 1.00 × 10 ⁻⁴ to 5.00 × 10 ^−2. 5.00 × 10 ⁻⁴ to 1.00 × 10 ⁻³ is more preferable.

The indentation hardness of the metal oxide particles is 400 MPa or more, preferably 450 MPa or more, and more preferably 550 MPa or more. The indentation hardness of the metal oxide particles is preferably 400 MPa or more because durability against pressure in the thickness direction of the moth-eye structure is increased. Further, the indentation hardness of the metal oxide particles is preferably 1000 MPa or less so as not to be brittle and easily broken.
The indentation hardness of the metal oxide particles can be measured with a nanoindenter or the like. As a specific measuring method, a sample can be measured by arranging metal oxide particles on a substrate (glass plate, quartz plate, etc.) harder than itself so that they do not overlap one or more steps and pressing them with a diamond indenter. At this time, it is preferable to fix with a resin or the like so that the particles do not move. However, when fixing with resin, it adjusts so that a part of particle | grain may be exposed. Moreover, it is preferable to specify a pushing position with a tribo indenter.
Also in this embodiment, a sample is prepared by arranging particles on a substrate and binding and fixing the particles using a small amount of curable resin so as not to affect the measurement value. Was used to determine the indentation hardness of the metal oxide particles.

The metal oxide particles are particularly preferably calcined silica particles because of the reasonably high amount of hydroxyl groups on the surface and hard particles.
The calcined silica particles are manufactured by a known technique in which silica particles are obtained by hydrolyzing and condensing a hydrolyzable silicon compound in an organic solvent containing water and a catalyst, and then the silica particles are calcined. For example, Japanese Patent Application Laid-Open Nos. 2003-176121 and 2008-137854 can be referred to.
Although it does not specifically limit as a raw material silicon compound which manufactures a burning silica particle, Chlorosilanes, such as tetrachlorosilane, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, methylvinyldichlorosilane, trimethylchlorosilane, methyldiphenylchlorosilane Compound: Tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, trimethoxyvinylsilane, triethoxyvinylsilane, 3-glycidoxypropyltrimethoxysilane, 3-chloro Propyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxy Silane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-chloropropylmethyldimethoxysilane, Alkoxysilane compounds such as diphenyldimethoxysilane, diphenyldiethoxysilane, dimethoxydiethoxysilane, trimethylmethoxysilane, trimethylethoxysilane; tetraacetoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, diphenyldiacetoxysilane Acyloxysilane compounds such as trimethylacetoxysilane; dimethylsilanediol, diphenylsilanediol, tri Silanol compounds such as chill silanol; and the like. Of the above-exemplified silane compounds, the alkoxysilane compound is particularly preferred because it is more easily available and the resulting fired silica particles do not contain halogen atoms as impurities. As a preferable form of the baked silica particles according to this embodiment, it is preferable that the halogen atom content is substantially 0% and no halogen atom is detected.
The firing temperature is not particularly limited, but is preferably 800 to 1300 ° C, and more preferably 1000 to 1200 ° C.

The calcined silica particles are preferably calcined silica particles whose surface is modified with a compound having a (meth) acryloyl group. By using calcined silica particles whose surface is modified with a compound having a (meth) acryloyl group, effects such as improvement in dispersibility in the composition for forming an antireflection layer, improvement in film strength, and prevention of aggregation can be expected. . For specific examples of the surface treatment method and preferred examples thereof, reference can be made to the descriptions in [0119] to [0147] of JP-A-2007-298974.

The shape of the metal oxide particles is most preferably spherical, but there is no problem even if it is other than a spherical shape such as an irregular shape.

As the metal oxide particles, commercially available particles may be used after firing. Specific examples include IPA-ST-L (average primary particle size 50 nm, silica sol manufactured by Nissan Chemical Industries, Ltd.), IPA-ST-ZL (average primary particle size 80 nm, silica sol manufactured by Nissan Chemical Industries, Ltd.) , Snowtex MP-1040 (average primary particle size 100 nm, silica manufactured by Nissan Chemical Industries, Ltd.), Snowtex MP-2040 (average primary particle size 200 nm, silica manufactured by Nissan Chemical Industries, Ltd.), Seahoster KE-P10 ( Average primary particle size 150 nm, Nippon Silica Co., Ltd. amorphous silica), Seahoster KE-P20 (average primary particle size 200 nm, Nippon Shokubai Co., Ltd. amorphous silica), ASFP-20 (average primary particle size 200 nm, Nippon Electrochemical) (Alumina manufactured by Kogyo Co., Ltd.) can be preferably used. Furthermore, as long as the requirements of the metal oxide particles of this embodiment are satisfied, commercially available particles may be used as they are.

The content ratio of the metal oxide particles and the binder resin is preferably 10/90 or more and 95/5 or less, more preferably 20/80 or more and 90/10 or less, (mass of metal oxide particles / binder resin mass), 30 / 70 to 85/15 is more preferable. It is preferable that (the mass of the metal oxide particles / the mass of the binder resin) is 10/90 or more because B / A of the concavo-convex shape of the moth-eye structure increases and the reflectance decreases. If the mass of the metal oxide particles / the mass of the binder resin is 95/5 or less, the adhesion between the metal oxide particles and the substrate is increased, or the metal oxide particles are less likely to aggregate during the manufacturing process, resulting in failure. Or haze deterioration is preferable.

The distribution of the distance A between the vertices of adjacent convex portions in the antireflection layer is preferably 200 nm or less. When the distribution of A is 200 nm or less, the distribution of the distance between particles is narrow (sharp), which means that the particles are present uniformly without approaching or extremely separated from each other. It is preferable from the viewpoint of a decrease in reflectance. The half width of the A distribution is more preferably 125 nm or less, and further preferably 100 nm or less.

(Binder resin)
The binder resin for the antireflection layer will be described.
The binder resin of the antireflection layer is a resin having a hydroxyl group. Since the binder resin of the antireflection layer is a resin having a hydroxyl group, even the above-described metal oxide particles having a surface hydroxyl group amount of 1.00 × 10 ⁻¹ or less are highly dispersible, Thus, the metal oxide particles do not aggregate, the haze of the antireflection layer can be lowered, and the reflectance can also be lowered.

The binder resin is preferably a resin obtained by polymerizing a polymerizable compound having at least one of a group having an ethylenically unsaturated double bond and an epoxy group, and the ethylenically unsaturated double bond as a polymerizable group It is preferable that it is resin obtained by superposing | polymerizing the polymeric compound which has only the group which has this.
The hydroxyl group equivalent of one molecule of the polymerizable compound is preferably 1 to 10,000, more preferably 100 to 5000, and still more preferably 200 to 3000. In this embodiment, the hydroxyl group equivalent is the molecular weight per hydroxyl group, and is a value obtained by dividing the molecular weight of the polymerizable compound by the number of hydroxyl groups contained in one molecule.
Examples of the polymerizable compound having a group having an ethylenically unsaturated double bond include a compound having a (meth) acryloyl group, a vinyl group, a styryl group, or an allyl group. Among them, a (meth) acryloyl group and —C (O) A compound having OCH═CH ₂ is preferable, and a compound having a (meth) acryloyl group is more preferable.

Specific examples of the polymerizable compound include (meth) acrylic acid diesters of alkylene glycol, (meth) acrylic acid diesters of polyoxyalkylene glycol, (meth) acrylic acid diesters of alcohol, ethylene oxide or propylene oxide adducts. Examples include (meth) acrylic acid diesters, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates.

Of these, esters of alcohol and (meth) acrylic acid are preferable (for example, 2-hydroxyethyl methacrylate), and esters of (poly) alcohol and (meth) acrylic acid are particularly preferable. For example, 2-hydroxyethyl acrylate (2-hydroxyethyl methacrylate) (hydroxyl group equivalent: 116), pentaerythritol triacrylate (hydroxyl group equivalent: 538), dipentaerythritol tetraacrylate (hydroxyl group equivalent: 228), dipenta Erythritol pentaacrylate (hydroxyl group equivalent: 524), 2-hydroxyethyl methacrylate (2-hydroxyethyl methacrylate) (hydroxyl group equivalent: 130), pentaerythritol trimethacrylate (hydroxyl group equivalent: 340), dipentaerythritol tetramethacrylate ( Hydroxyl group equivalent: 256), dipentaerythritol pentamethacrylate (hydroxyl group equivalent: 594) and the like.

A commercially available compound can also be used as the polymerizable compound. Specifically, for example, NK ester 701A (manufactured by Shin-Nakamura Chemical Co., Ltd.) (hydroxyl group equivalent: 200), NK ester ACB-21 (manufactured by Shin-Nakamura Chemical Co., Ltd.) (hydroxyl group equivalent: 292) , KAYARAD PET30 (manufactured by Nippon Kayaku Co., Ltd.) (hydroxyl group equivalent: 533), NK ester A-TMM3 (manufactured by Shin-Nakamura Chemical Co., Ltd.) (hydroxyl group equivalent: 897), KAYARAD DPHA (Nippon Kayaku) (Hydroxyl group equivalent: 1102), Aronix M-402 (manufactured by Toa Gosei Co., Ltd.) (hydroxyl group equivalent: 1597), Aronix M-405 (manufactured by Toa Gosei Co., Ltd.) (hydroxyl) Group equivalent: 3799), Aronix M-450 (manufactured by Toagosei Co., Ltd.) (hydroxyl group equivalent: 6986), and the like.

A polymerizable compound may be used by mixing a plurality of compounds. At this time, the molecular weight is an average molecular weight depending on the blending ratio of the polymerizable compound, and the hydroxyl group equivalent is also a value obtained by dividing this by the average number of hydroxyl groups per molecule.

[Method for producing antireflection film]
Although the manufacturing method of the antireflection film of this aspect is not specifically limited, From the viewpoint of production efficiency, a manufacturing method using a coating method is preferable.
That is, the manufacturing method of the antireflection film is:
A method for producing an antireflection film comprising a base material, and an antireflection layer containing a binder resin and metal oxide particles having an average primary particle size of 50 nm to 250 nm,
The surface of the metal oxide particles has a hydroxyl group amount of 1.00 × 10 ⁻¹ or less,
The indentation hardness of the metal oxide particles is 400 MPa or more,
The binder resin is a resin having a hydroxyl group,
The antireflection layer has a moth-eye structure composed of irregularities formed of metal oxide particles on the surface opposite to the substrate side interface,
A step of applying a composition for forming an antireflection layer containing a polymerizable compound for forming a binder resin having a polymerizable functional group and metal oxide particles having an average primary particle size of 50 nm to 250 nm on a substrate. It is a manufacturing method of the antireflection film which has.

The polymerizable compound for forming a binder resin having a polymerizable functional group and the metal oxide particles having an average primary particle size of 50 nm or more and 250 nm or less contained in the composition for forming an antireflection layer are the same as those described above.
The composition for forming an antireflection layer may contain a solvent, a polymerization initiator, a particle dispersing agent, a leveling agent, an antifouling agent and the like.
A solvent having a polarity close to that of the fine particles is preferably selected from the viewpoint of improving dispersibility. Specifically, for example, when the fine particles are metal oxide particles, an alcohol solvent is preferable, and examples thereof include methanol, ethanol, 2-propanol, 1-propanol, and butanol. For example, when the fine particles are metal resin particles or resin particles having a hydrophobic surface modified, ketone-based, ester-based, carbonate-based, alkane, aromatic-based solvents are preferable, and methyl ethyl ketone (MEK), dimethyl carbonate , Methyl acetate, acetone, methylene chloride, cyclohexanone and the like. These solvents may be used in a mixture of a plurality of types as long as the dispersibility is not significantly deteriorated.
The particle dispersing agent can facilitate uniform arrangement of the particles by reducing the cohesive force between the particles. The dispersant is not particularly limited, but is preferably an anionic compound such as a sulfate or phosphate, a cationic compound such as an aliphatic amine salt or a quaternary ammonium salt, a nonionic compound or a polymer compound. And a steric repulsion group are more preferred because they have a high degree of freedom in selection. A commercial item can also be used as a dispersing agent. For example, BYK Japan made of (stock) DISPERBYK160, DISPERBYK161, DISPERBYK162, DISPERBYK163, DISPERBYK164, DISPERBYK166, DISPERBYK167, DISPERBYK171, DISPERBYK180, DISPERBYK182, DISPERBYK2000, DISPERBYK2001, DISPERBYK2164, Bykumen, BYK-2009, BYK-P104, BYK-P104S, BYK-220S, Anti-Terra 203, Anti-Terra 204, Anti-Terra 205 (trade name) and the like.
By reducing the surface tension of the coating solution, the leveling agent can stabilize the solution after coating and facilitate the uniform arrangement of particles and binder resin. For example, the compounds described in JP-A-2004-331812 and JP-A-2004-163610 can be used.
The antifouling agent can suppress adhesion of dirt and fingerprints by imparting water and oil repellency to the moth-eye structure. For example, compounds described in JP 2012-88699 A can be used.

(Polymerization initiator)
When the polymerizable compound for forming a binder resin is a photopolymerizable compound, the composition for forming an antireflection layer preferably contains a photopolymerization initiator.
As photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, Examples include fluoroamine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, and coumarins. Specific examples, preferred embodiments, commercially available products, and the like of the photopolymerization initiator are described in paragraphs [0133] to [0151] of JP-A-2009-098658, and can be suitably used in this embodiment as well. it can.
“Latest UV Curing Technology” {Technical Information Association, Inc.} (1991), p. 159, and “UV Curing System” written by Kiyomi Kato (published by the General Technology Center in 1989), p. Various examples are also described in 65 to 148 and are useful in this embodiment.

(Other additives)
The antireflection layer may contain fine particles different from the metal oxide particles described above. In this case, in order not to disturb the shape of the moth-eye structure, it is necessary to be smaller than the metal oxide fine particles. As the other fine particles, particles having an average primary particle size of 50 nm or more and less than 120 nm are preferable because aggregation of metal oxide fine particles may be suppressed and reflectance and haze may be reduced. Specific examples of the other fine particles include, for example, organosilica sol IPA-ST, IPA-ST-L, IPA-ST-ZL, MEK-ST, MEK-ST-L, MEK-ST-ZL, MEK- AC-4130Y, MEK-AC-5140Z, Thruria 2320, 4320, 5320 (above, unsintered silica particle dispersion manufactured by Nissan Chemical Co., Ltd.), Seahoster KE-P10 (Non-Sintered silica manufactured by Nippon Shokubai Co., Ltd.) Particles), XX-242S (cross-linked polymethyl methacrylate particles manufactured by Sekisui Plastics Co., Ltd.), and the like.

Hereinafter, the present invention will be described more specifically with reference to examples. The amounts, ratios and operations of materials, reagents, and substances shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the following specific examples.

<Examples and comparative examples of the first aspect of the present invention>
(Production of substrate with hard coat layer)
A cellulose triacetate film (TDH60UF, manufactured by Fuji Film Co., Ltd.) is coated with a coating solution for forming a hard coat layer having the following composition, and irradiated with ultraviolet rays having an irradiation amount of 60 mJ / cm ² with an air-cooled metal halide lamp while purging with nitrogen. It hardened | cured and formed the hard-coat layer with a film thickness of 8 micrometers. Thus, the base material with a hard-coat layer was produced.

<Composition of coating liquid for forming hard coat layer>
A-TMMT 44.6 parts by weight Irgacure 127 1.9 parts by weight Methyl ethyl ketone 10.7 parts by weight Methyl isobutyl ketone 37.5 parts by weight Methyl acetate 5.4 parts by weight

(Preparation of coating solution for antireflection layer formation)
Each component is put into a mixing tank so as to have the composition shown in Table 1 below, stirred for 60 minutes, dispersed with an ultrasonic disperser for 30 minutes, and filtered through a polypropylene filter having a pore size of 5 μm to form a coating solution for forming an antireflection layer. It was.
As (A), (B) and (C) in Table 1 below, compositions for forming an antireflection layer in each Example and Comparative Example were prepared using the materials described in Table 2 below.

In Table 1 above, the unit of the amount of each component represents “parts by mass”.
Moreover, (B) and (C) were used so that it might become 32.4 mass parts in total as a compound for binder resin formation.

(Preparation of antireflection film)
On the hard coat layer of the substrate with a hard coat layer, each antireflection layer forming composition using the materials described in Table 2 below as (A), (B) and (C) is wetted using a gravure coater. After applying at a coating amount of about 2.8 ml / m ² and drying at 120 ° C. for 5 minutes, the irradiation amount is 600 mJ / cm with an air-cooled metal halide lamp while purging with nitrogen so that the atmosphere has an oxygen concentration of 0.1% by volume or less. ^The film was cured by being irradiated with the ultraviolet ray ² to produce antireflection films of Examples 1 to 34 and Comparative Examples 1 to 5.

Example except that Fujitac TG60UL (manufactured by FUJIFILM Corporation) was used instead of the cellulose triacetate film (TDH60UF, manufactured by FUJIFILM Corporation), and the composition for forming an antireflection layer having the composition shown in Table 3 below was used. In the same manner as in Example 1, antireflection films of Examples 35 to 51 were produced.

(Evaluation of antireflection film)
Various characteristics of the antireflection film were evaluated by the following methods. The results are shown in Table 2.

(Integral reflectance)
The back surface of the antireflection film (cellulose triacetate film side) is roughened with sandpaper, then treated with black ink, and the back surface reflection is eliminated. With ARV-474 attached, the integrated reflectance at an incident angle of 5 ° was measured in the wavelength region of 380 to 780 nm, and the average reflectance was calculated to evaluate the antireflection property.

(Pencil hardness test and eraser rub test after pencil hardness test)
A pencil hardness test (H / 2H / 3H) was performed on the surface of the antireflection layer, and then the pencil was removed with an eraser.
The pencil hardness test was performed by the pencil hardness evaluation method specified by JIS-K5400 using a test pencil specified by JIS-S6006 after humidity was adjusted for 2 hours at 25 ° C. and a relative humidity of 60%.
Using a rubbing tester, the pencil test part was rubbed with an eraser.
Evaluation environmental conditions: 25 ° C., 60% RH.
Rubbing material: A plastic eraser {"MONO" manufactured by Dragonfly Pencil Co., Ltd.) was fixed to the rubbing tip (1 cm x 1 cm) of the tester that was in contact with the sample.
Rub speed: 2 cm / sec
Load: 250 g / cm ²
Tip contact area: 1 cm x 1 cm
Number of rubbing: 50 reciprocations The number of particles was counted from SEM photographs of the pencil test unexecuted part and the implemented part, and the residual ratio of the particles was calculated.
Particle residual ratio = (number of particles per unit area of pencil hardness test execution part / number of particles per unit area of pencil hardness test non-execution part) × 100
A: Particle residual ratio of 80% or more B: Particle residual ratio of 60% or more and less than 80% C: Particle residual ratio of less than 60%

(B / A)
The antireflection film sample was cut with a microtome to obtain a cross section, and the cross section was etched for 10 minutes after carbon deposition. Using a scanning electron microscope (SEM), 20 fields of view were observed and photographed at a magnification of 5000 times. In the obtained image, at the interface between the air and the sample, the distance A between the vertices of the adjacent convex portions and the distance B between the vertices of the adjacent convex portions and the concave portion are measured by 100 points, and B / A It was calculated as an average value.

In Table 2 and Table 3, (C) / ((B) + (C)) is a mass ratio of the content of the compound (C) to the total content of the compound (B) and the compound (C).
In Examples 19 to 28 and 39 to 48, a compound corresponding to the compound (C) is used as the surface treatment coupling agent for the metal oxide particles (A) (corresponding to the second embodiment described above).

The compounds used are shown below.
Irgacure 127: Photopolymerization initiator (manufactured by BASF Japan Ltd.)
KE-S10: Sea Hoster KE-S10 Nippon Shokubai KE-S30: Sea Hoster KE-S30 Nippon Shokubai

[Synthesis of Silica Particle A1]
A 200 L reactor equipped with a stirrer, a dropping device and a thermometer was charged with 67.54 kg of methyl alcohol and 26.33 kg of 28% by mass ammonia water (water and catalyst), and the liquid temperature was kept at 33 ° C. while stirring. Adjusted. Meanwhile, a dropping device was charged with a solution in which 12.70 kg of tetramethoxysilane was dissolved in 5.59 kg of methyl alcohol. While maintaining the liquid temperature in the reactor at 33 ° C., the above solution was dropped from the dropping device over 1 hour, and after completion of the dropwise addition, stirring was continued for 1 hour while maintaining the liquid temperature at the above temperature. Hydrolysis and condensation of methoxysilane was performed to obtain a dispersion containing a silica particle precursor. Silica particles were obtained by air-drying this dispersion under the conditions of a heated tube temperature of 175 ° C. and a reduced pressure of 200 torr (27 kPa) using an instantaneous vacuum evaporator (Crox system CVX-8B type manufactured by Hosokawa Micron Corporation). A1 was obtained. The average particle size was 200 nm, and the degree of dispersion (Cv value) of the particle size was 3.5%.

[Preparation of calcined silica particles A2]
5 kg of silica particles A1 were put in a crucible, fired at 1050 ° C. for 1 hour using an electric furnace, cooled, and then ground using a grinder to obtain pre-classified fired silica particles. Further, pulverized silica particles A2 were obtained by pulverization and classification using a jet pulverization classifier (IDS-2 type, manufactured by Nippon Puma Co., Ltd.). The average particle diameter of the obtained silica particles was 200 nm, and the degree of dispersion (Cv value) of the particle diameter was 3.5%.

[Production of Silane Coupling Agent-treated Silica Particles A3-C1 to A3-C6]
5 kg of pre-classified sintered silica particles A2 were charged into a 20 L Henschel mixer (FM20J type, manufactured by Mitsui Mining Co., Ltd.) equipped with a heating jacket. While the calcined silica particles A2 were being stirred, a solution prepared by dissolving 45 g of C1 to C6 in 90 g of methyl alcohol was added dropwise and mixed. Then, it heated up to 150 degreeC over about 1 hour, mixing and stirring, and hold | maintained at 150 degreeC for 12 hours, and heat-processed. In the heat treatment, scrapes on the wall surface were scraped while the scraping device was always rotated in the direction opposite to the stirring blade. Moreover, the wall deposits were also scraped off using a spatula as appropriate. After heating and cooling, pulverization and classification were performed using a jet pulverization classifier to obtain silane coupling agent-treated silica particles A3-C1 to A3-C6. In each case, the average particle size was 210 nm, and the degree of dispersion (Cv value) of the particle size was 3.7%.

[C1]
To a flask equipped with a reflux condenser and a thermometer, 13.6 g of Shin-Etsu Chemical KBE-9007, 16.4 g of pentaerythritol triacrylate, 0.1 g of dibutyltin dilaurate and 70.0 g of toluene were added, and 12 hours at room temperature. Stir. After stirring, 500 ppm of methylhydroquinone was added and distilled off under reduced pressure to obtain C1.

[C2]
9.1 g of Shin-Etsu Chemical KBE-9007, 20.9 g of 1,3-diacryloyloxy-2-propanol, 0.1 g of dibutyltin dilaurate and 70.0 g of toluene were added to a flask equipped with a reflux condenser and a thermometer. And stirred at room temperature for 12 hours. After stirring, 500 ppm of methylhydroquinone was added and distilled off under reduced pressure to obtain C2.

[C3]
In a flask equipped with a reflux condenser and a thermometer, 19.3 g of KBE-9007 manufactured by Shin-Etsu Chemical Co., Ltd., 3.9 g of glycerin 1,3-bisacrylate, 6.8 g of 2-hydroxyethyl acrylate, 0.1 g of dibutyltin dilaurate, 70.0 g of toluene was added and stirred at room temperature for 12 hours. After stirring, 500 ppm of methylhydroquinone was added and distilled off under reduced pressure to obtain C3.

[C5]
To a flask equipped with a reflux condenser and thermometer, 9.1 g of KBE-9007 manufactured by Shin-Etsu Chemical Co., Ltd., 20.9 g of dipentaerythritol pentaacrylate, 0.1 g of dibutyltin dilaurate and 70.0 g of toluene were added, and 12 hours at room temperature. Stir. After stirring, it was evaporated under reduced pressure to obtain C5.

[C7] X-40-2671G manufactured by Shin-Etsu Chemical
X-40-2671G is represented by the general formula (2) described in JP-A-2007-41495. Here, R ¹ is a hydrogen atom, Y is * —COO — **, L is a linking group having 3 carbon atoms (C ₃ H ₆ ), R ² , R ³ and R ⁴ are methoxy groups, R ⁵ , R ⁶ is a methyl group. The weight average molecular weight was 1300-1900.

KAYARAD PET-30: A mixture of pentaerythritol tetraacrylate and pentaerythritol triacrylate (manufactured by Nippon Kayaku Co., Ltd.)
KAYARAD DPHA: Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
Light ester HO-250 (N): hydroxylethyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)
A-DPH: Dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Kogyo)
A-TMMT: Pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Kogyo)

<Examples and comparative examples of the second aspect of the invention>
[Synthesis of Silica Particles a-1]
A 200 L reactor equipped with a stirrer, a dropping device and a thermometer was charged with 67.54 kg of methyl alcohol and 26.33 kg of 28% by mass ammonia water (water and catalyst), and the liquid temperature was kept at 33 ° C. while stirring. Adjusted. Meanwhile, a dropping device was charged with a solution in which 12.70 kg of tetramethoxysilane was dissolved in 5.59 kg of methyl alcohol. While maintaining the liquid temperature in the reactor at 33 ° C., the above solution was dropped from the dropping device over 1 hour, and after completion of the dropwise addition, stirring was continued for 1 hour while maintaining the liquid temperature at the above temperature. Hydrolysis and condensation of methoxysilane was performed to obtain a dispersion containing a silica particle precursor. Silica particles were obtained by air-drying this dispersion under the conditions of a heated tube temperature of 175 ° C. and a reduced pressure of 200 torr (27 kPa) using an instantaneous vacuum evaporator (Crox system CVX-8B type manufactured by Hosokawa Micron Corporation). a-1 was obtained. The average particle size was 200 nm, and the degree of particle size dispersion (Cv value) was 3.5%.

[Preparation of calcined silica particles b-1]
5 kg of silica particles a-1 were put in a crucible, fired at 900 ° C. for 1 hour using an electric furnace, cooled, and then ground using a grinder to obtain pre-classified fired silica particles. Further, pulverized silica particles b-1 were obtained by crushing and classifying using a jet crushing and classifying machine (IDS-2 type, manufactured by Nippon Puma Co., Ltd.). The average particle diameter of the obtained silica particles was 200 nm, and the degree of dispersion (Cv value) of the particle diameter was 3.5%.

[Preparation of calcined silica particles b-2]
5 kg of silica particles a-1 were placed in a crucible, fired at 900 ° C. for 2 hours using an electric furnace, cooled, and then ground using a grinder to obtain pre-classified fired silica particles. Further, pulverized silica particles b-2 were obtained by pulverization and classification using a jet pulverization classifier (IDS-2 type, manufactured by Nippon Puma Co., Ltd.). The average particle diameter of the obtained silica particles was 200 nm, and the degree of dispersion (Cv value) of the particle diameter was 3.5%.

[Preparation of calcined silica particles b-3]
5 kg of silica particles a-1 were placed in a crucible, fired at 1050 ° C. for 1 hour using an electric furnace, cooled, and then pulverized using a pulverizer to obtain pre-classified baked silica particles. Further, pulverized silica particles b-3 were obtained by pulverization and classification using a jet pulverization classifier (IDS-2 type, manufactured by Nippon Puma Co., Ltd.). The average particle diameter of the obtained silica particles was 200 nm, and the degree of dispersion (Cv value) of the particle diameter was 3.5%.

[Preparation of calcined silica particles b-4]
2 kg each of silica particles b-1 and b-3 were put into a high-speed stirring mixer Spartan mixer (manufactured by DULTON), stirred for 30 minutes and then taken out to obtain calcined silica particles b-4. The average particle diameter of the obtained silica particles was 200 nm, and the degree of dispersion (Cv value) of the particle diameter was 23%.

[Preparation of calcined silica particles b-5]
25 kg of silica-based hollow fine particle dispersion sol (manufactured by Catalyst Kasei Kogyo Co., Ltd .: Thruria 1420-120, average particle size 120 nm, concentration 20.5 wt%, dispersion medium: isopropanol, particle refractive index 1.20) in a crucible The isopropanol was evaporated in an oven at 100 ° C. Next, after baking for 1 hour at 1050 ° C. using an electric furnace, the mixture was cooled and then pulverized using a pulverizer to obtain pre-classified baked silica particles. Further, pulverized silica particles b-5 were obtained by pulverization and classification using a jet pulverization classifier (IDS-2 type, manufactured by Nippon Puma Co., Ltd.). The average particle diameter of the obtained silica particles was 120 nm, and the degree of dispersion (Cv value) of the particle diameter was 5.0%.

[Production of Silane Coupling Agent-treated Silica Particles c-1]
Pre-classified calcined silica particles b-2 (5 kg) were charged into a 20 L Henschel mixer (FM20J type, manufactured by Mitsui Mining Co., Ltd.) equipped with a heating jacket. While the calcined silica particles b-2 were being stirred, a solution prepared by dissolving 45 g of 3-acryloxypropyltrimethoxysilane (KBM5103 manufactured by Shin-Etsu Chemical Co., Ltd.) in 90 g of methyl alcohol was added dropwise and mixed. Then, it heated up to 150 degreeC over about 1 hour, mixing and stirring, and hold | maintained at 150 degreeC for 12 hours, and heat-processed. In the heat treatment, scrapes on the wall surface were scraped while the scraping device was always rotated in the direction opposite to the stirring blade. Moreover, the wall deposits were also scraped off using a spatula as appropriate. After heating, the mixture was cooled, and pulverized and classified using a jet pulverizer to obtain silica particles c-1 treated with a silane coupling agent. The average particle size was 210 nm, and the degree of dispersion (Cv value) of the particle size was 3.7%.

[Measurement of hydroxyl group content on particle surface]
Using solid ²⁹ Si NMR, signal intensities Q2 and Q1 were measured under the following conditions to calculate the amount of hydroxyl groups (Q1 × 3 + Q2 × 2).
Measuring method: ²⁹ Si CP / MAS
Observation frequency: ²⁹ Si: 59.63 MHz
Spectral width: 22675.74 Hz
Total number of times: 2000 times Contact time: 5 ms
90 ° pulse: 4.8 μs
Measurement waiting time: 2 seconds MAS rotation speed: 3 kHz
Chemical shift: Q2 is -91 to -94 ppm, Q1 is -100 to -102 ppm

[Measurement of indentation hardness of metal oxide particles]
8 g of each metal oxide particle, 0.3 g of Irgacure 184 (manufactured by BASF Japan Ltd.), 7.7 g of KAYARAD PET30 (manufactured by Nippon Kayaku Co., Ltd.) are added to 91 g of ethanol, and after stirring for 10 minutes, The dispersion was carried out for 10 minutes with a sonic disperser to obtain a 15% by mass dispersion. This dispersion W period was applied to a glass plate at a wet application amount of about 3 ml / m ² , and an irradiation amount of 600 mJ / cm ² was applied with an air-cooled metal halide lamp while purging with nitrogen so that the oxygen concentration was 0.1 vol% or less. Cured by UV irradiation. Thereafter, it was observed with SEM that the metal oxide particles were not stacked in one or more stages. The indentation hardness of the metal oxide particles was measured for this sample using a triboindenter (TI-950 manufactured by Heiditron) under a diamond indenter with a diameter of 1 μm and an indentation load of 0.05 mN.

[Preparation of antireflection films A-1 and A-2]
10 g of silica particles a-1 was added to 10 g of ethanol placed in a glass container, and ultrasonic waves were applied until no solid matter could be visually confirmed to obtain a milky white suspension. Next, 15 g of acrylic monomer (M-350 manufactured by Toagosei Co., Ltd.) was added to the suspension in the glass container, stirred well, and then placed in a dryer maintained at 45 ° C. together with the glass container. After evaporating about 5 g of ethanol from the suspension, 0.2 g of photopolymerization initiator (trade name “DAROCUR1173” manufactured by Ciba Specialty Chemicals) was added to prevent the silica particles from being dispersed in the acrylic monomer. A layer forming coating solution A-1 was obtained.

Next, coating solution A-1 for forming an antireflection layer was dropped on the surface of a 100 mm square glass substrate (alkali glass manufactured by Asahi Techno Glass Co., Ltd.) that had been surface cleaned with a UV / ozone cleaner in advance, and a spin coater. Was used to rotate the glass substrate under the conditions of 200 rpm for 120 seconds and then 600 rpm for 120 seconds to apply the coating solution A-1 for forming an antireflection layer over the entire surface of the glass substrate. Thereafter, the substrate coated with the coating liquid A-1 for forming the antireflection layer is conveyed to a glove box in a nitrogen atmosphere, and the acrylic monomer is cured by photopolymerization by irradiating with a UV cure lamp in the glove box for 1 minute. A transparent resin film in which silica particles were dispersed in an acrylic resin on a glass substrate was obtained. *

Next, the surface of the obtained transparent resin film is subjected to plasma treatment using a high-frequency plasma apparatus under conditions of 13.56 MHz to etch the acrylic resin in the transparent resin film, thereby revealing the uneven shape on the surface. As a result, an antireflection film A-1 was obtained. The plasma treatment was performed by applying a high frequency of 50 W for 30 seconds under a pressure of 2.7 Pa while introducing a gas having a composition of oxygen: argon = 1: 1. Moreover, the film thickness of the obtained antireflection layer was 20 μm.

An antireflection film A-2 was produced in the same manner as the antireflection film A-1, except that the silica particles b-1 were used in place of the silica particles a-1 (antireflection layer forming coating solution A-2). The film thickness of the obtained antireflection film was 20 μm.

[Preparation of antireflection films B-1 to B-4, C-1 to C-11]
(Preparation of coating solution for antireflection layer formation)
Each component is put into a mixing tank so as to have the composition shown in Table 4 below, stirred for 60 minutes, dispersed by an ultrasonic disperser for 30 minutes, and filtered through a polypropylene filter having a pore size of 5 μm to form a coating solution for forming an antireflection layer. It was.
In the following Table 4, the numerical value of each component represents the amount (parts by mass) added. The unit of the coating solution concentration is “mass%”. For metal oxide particles, the hydroxyl group equivalent, indentation hardness, and average primary particle size dispersity Cv value are listed.

The compounds used are shown below.
KAYARAD PET30 (manufactured by Nippon Kayaku Co., Ltd.): a mixture of 60% pentaerythritol triacrylate and 40% pentaerythritol tetraacrylate KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.): 50% dipentaerythritol pentaacrylate Aronix M-405 (manufactured by Toagosei Co., Ltd.): A mixture of 15% dipentaerythritol pentaacrylate and 85% dipentaerythritol hexaacrylate Aronix M-450 (Toagosei Co., Ltd.) ) Manufactured by :) Mixture of 5% pentaerythritol triacrylate and 95% pentaerythritol tetraacrylate Seahoster KE-S30 (manufactured by Nippon Shokubai Co., Ltd.): average primary particle size of about 300 nm
Irgacure 184: Photopolymerization initiator (manufactured by BASF Japan Ltd.)

(Preparation of antireflection films B-1 to B-4)
On a cellulose triacetate film (TDH60UF, manufactured by FUJIFILM Corporation) as a transparent substrate having a thickness of 60 μm, an antireflection layer-forming coating solution B-1 is applied at a wet coating amount of about 2.8 ml / m ² using a gravure coater. After being coated with and dried at 120 ° C. for 5 minutes, it was cured by irradiating with an ultraviolet ray with an irradiation amount of 600 mJ / cm ² with an air-cooled metal halide lamp while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.1% by volume or less. An antireflection film B-1 was produced. At this time, the wet coating amount was finely adjusted to measure the particle occupancy, and the highest one was adopted as the antireflection film B-1. Antireflection films B-2 to B-4 were prepared in the same manner except that the antireflection layer forming coating solutions B-2 to B-4 were used instead of the antireflection layer forming coating solution B-1.

(Preparation of composition for forming hard coat layer)
10.5 parts by mass of methyl acetate, 10.5 parts by mass of MEK, 22.52 parts by mass of NK ester A-TMMT (manufactured by Shin-Nakamura Chemical Co., Ltd.), AD-TMP (manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 6.30 parts by mass and 0.84 parts by mass of Irgacure 184 were added, stirred, and filtered through a polypropylene filter having a pore size of 0.4 μm to obtain a hard coat layer coating solution (solid content concentration: 58% by mass). .

(Preparation of antireflection films C-1 to C-11)
On a cellulose triacetate film (TDH60UF, manufactured by Fuji Film Co., Ltd.), a hard coat layer-forming coating solution is applied and cured by irradiating an ultraviolet ray with an irradiation amount of 30 mJ / cm ² with an air-cooled metal halide lamp while purging with nitrogen. A hard coat layer having a thickness of 6 μm was formed. Thus, the base material with a hard-coat layer was produced.
On the hard coat layer of the substrate with the hard coat layer, the antireflection layer forming coating solution C-1 was applied at a wet application amount of about 2.8 ml / m ² using a gravure coater, and dried at 120 ° C. for 5 minutes. Thereafter, the film was cured by irradiating with an ultraviolet ray with an irradiation amount of 600 mJ / cm ² with an air-cooled metal halide lamp while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.1% by volume or less, thereby producing an antireflection film C-1. At this time, the wet coating amount was finely adjusted to measure the particle occupancy, and the highest one was adopted as the antireflection film C-1. The coating liquids C-2 to C-11 for forming the antireflection layer were used in place of the coating liquid C-1 for forming the antireflection layer, and the wet coating amount was the same as when the antireflection film C-1 was formed. Antireflection films C-2 to C-11 were produced in the same manner.

(Evaluation of antireflection film)
Various characteristics of the antireflection film were evaluated by the following methods. The results are shown in Table 5.

(Haze)
The uniformity of the surface was evaluated by the haze value. When the particles are aggregated and non-uniform, the haze increases. The total haze value (%) of the obtained film was measured according to JIS-K7136. Nippon Denshoku Industries Co., Ltd. haze meter NDH4000 was used for the apparatus.
Haze value is 2% or less: No cloudiness and excellent surface uniformity.
The haze value is 5% or less, although there is a slight cloudiness, but there is no problem in appearance.
The haze value is larger than 5% ... The cloudiness is strong and the appearance is impaired.

(Durability to pressure in the thickness direction of the moth-eye structure)
The substrate side of the antireflection film sample is attached to a glass plate, and a scratch test is performed on the antireflection layer surface using a diamond indenter with a diameter of 25 μm under the conditions of 20 g load and 810 mm / min. Were observed and evaluated according to the following criteria.
A: After the test you can't see the rest B: You can see the weak after the test but there is no problem

(B / A, half width of A distribution)
The antireflection film sample was cut with a microtome to obtain a cross section, and the cross section was etched for 10 minutes after carbon deposition. Using a scanning electron microscope (SEM), 20 fields of view were observed and photographed at a magnification of 5000 times. In the obtained image, at the interface between the air and the sample, the distance A between the vertices of the adjacent convex portions and the distance B between the vertices of the adjacent convex portions and the concave portion are measured by 100 points, and B / A It was calculated as an average value. The half-value width of the A distribution was also calculated.

(Pencil hardness)
The pencil hardness evaluation described in JIS K5400 was performed. The antireflection film sample was conditioned at a temperature of 25 ° C. and a humidity of 60% RH for 3 hours, then tested on the antireflection layer surface using a test pencil specified in JIS S6006, and evaluated according to the following criteria.
A: After the test you can't see the rest B: You can see the weak after the test but there is no problem

Comparing Comparative Samples A-1 and A-2, increasing the indentation hardness of the particles improves the durability of the moth-eye structure against the pressure in the thickness direction and can suppress the collapse of the particles. Thus, it can be seen that the dispersibility is poor due to the absence of haze and haze and reflectance are deteriorated. On the other hand, in the sample samples B-1 to B-4 and C-1 to C-4 of the present invention, the binder resin has a hydroxyl group, so that the reflectance and haze are excellent, and B-1, B- It can be seen that the 2, C-1, and C-2 samples are particularly excellent.
Regarding the indentation hardness of the particles, Example Sample C-2 showed good durability in the thickness direction, C-5 and C-6 samples were more excellent, and excellent in the pencil hardness test. It was confirmed that there was an effect. Further, by comparing the comparative sample C-11 at the same time, it was confirmed that this effect was dependent on the indentation hardness of the particles, not on the decrease in the amount of hydroxyl on the particle surface by firing.
Example Sample C-8 has the highest reflectivity, which is considered to be due to the large B / A.

[Example 2]
[Synthesis of Silica Particles a-7]
A 200-liter reactor equipped with a stirrer, a dropping device and a thermometer was charged with 101.01 kg of methyl alcohol and 6.58 kg of 28% by mass aqueous ammonia (water and catalyst), and the liquid temperature was kept at 33 ° C. while stirring. Adjusted. Meanwhile, a dropping device was charged with a solution obtained by dissolving 3.18 kg of tetramethoxysilane in 1.40 kg of methyl alcohol. While maintaining the liquid temperature in the reactor at 33 ° C., the above solution was dropped from a dropping device over 45 minutes to hydrolyze and condense tetramethoxysilane, thereby obtaining a dispersion containing a silica particle precursor. . Silica particles were obtained by air-drying this dispersion under the conditions of a heated tube temperature of 175 ° C. and a reduced pressure of 200 torr (27 kPa) using an instantaneous vacuum evaporator (Crox system CVX-8B type manufactured by Hosokawa Micron Corporation). a-7 was obtained. The average particle size was 90 nm, and the degree of particle size dispersion (Cv value) was 8%.

[Synthesis of Silica Particles a-8]
A 200 L reactor equipped with a stirrer, a dropping device and a thermometer was charged with 108.93 kg of methyl alcohol and 2.37 kg of 28% by mass ammonia water (water and catalyst), and the liquid temperature was kept at 25 ° C. while stirring. Adjusted. On the other hand, a dropping device was charged with a solution prepared by dissolving 1.14 kg of tetramethoxysilane in 0.50 kg of methyl alcohol. While maintaining the liquid temperature in the reactor at 33 ° C., the above solution was dropped from the dropping device over 1 hour, and after completion of the dropwise addition, stirring was continued for 1 hour while maintaining the liquid temperature at the above temperature. Hydrolysis and condensation of methoxysilane was performed to obtain a dispersion containing a silica particle precursor. Silica particles were obtained by air-drying this dispersion under the conditions of a heated tube temperature of 175 ° C. and a reduced pressure of 200 torr (27 kPa) using an instantaneous vacuum evaporator (Crox system CVX-8B type manufactured by Hosokawa Micron Corporation). a-8 was obtained.

[Synthesis of Silica Particles a-9 to a-11]
Tetramethoxysilane was hydrolyzed and condensed by the same method as the synthesis of silica particles a-7, except that the dropping time of the above solution was changed from a dropping device to 8 minutes, 20 minutes, and 50 minutes, respectively. Silica particles a-9 to a-11 were obtained.

[Synthesis of Silica Particles a-12]
Except for performing the hydrolysis and condensation of tetramethoxysilane by changing the dropping time of the above solution from the dropping device to 60 minutes, and stirring the liquid temperature while maintaining the liquid temperature at the above temperature for another 20 minutes after the dropping. Silica particles a-12 were obtained by a method similar to the synthesis of silica particles a-7.

[Synthesis of Silica Particles a-13]
Silica particles a-13 were obtained by the same method as the synthesis of silica particles a-12, except that the stirring time after completion of the addition was further changed to 40 minutes.

[Preparation of calcined silica particles b-7]
5 kg of silica particles a-7 were placed in a crucible, fired at 900 ° C. for 1 hour using an electric furnace, cooled, and then ground using a grinder to obtain pre-classified fired silica particles. Further, pulverized silica particles b-7 were obtained by pulverization and classification using a jet pulverization classifier (IDS-2 type, manufactured by Nippon Puma Co., Ltd.). The average particle diameter of the obtained silica particles was 90 nm, and the dispersion degree of particle diameter (Cv value) was 8%.

[Preparation of calcined silica particles b-8 to b-13]
The silica particles a-7 were changed to silica particles a-8 to a-13, respectively, and the calcined silica particles b-8 to b- were prepared in the same manner as the calcined silica particles b-7, except that the calcining time was changed to 2 hours. 13 was produced.

[Preparation of Silane Coupling Agent-treated Silica Particles c-8]
Pre-classified calcined silica particles b-8 (5 kg) were charged into a 20 L Henschel mixer (FM20J type, manufactured by Mitsui Mining Co., Ltd.) equipped with a heating jacket. While the calcined silica particles b-8 were being stirred, a solution of 600 g of 3-acryloxypropyltrimethoxysilane (KBM5103 manufactured by Shin-Etsu Chemical Co., Ltd.) dissolved in 1200 g of methyl alcohol was added dropwise and mixed. Then, it heated up to 150 degreeC over about 1 hour, mixing and stirring, and hold | maintained at 150 degreeC for 12 hours, and heat-processed. In the heat treatment, scrapes on the wall surface were scraped while the scraping device was always rotated in the direction opposite to the stirring blade. Moreover, the wall deposits were also scraped off using a spatula as appropriate. After heating, the mixture was cooled, and pulverized and classified using a jet pulverizer to obtain silane coupling agent-treated silica particles c-8.

[Preparation of Silica Coupling Agent-treated Silica Particles c-9 to c-13]
The calcined silica particles b-8, calcined silica particles b-9 to b-13, 3-acryloxypropyltrimethoxysilane 180 g, 129 g, 95 g, 82 g, 75 g, methyl alcohol 360 g, 257 g, respectively. Except for changing to 189 g, 164 g, and 150 g, calcined silica particle silane coupling agent-treated silica particles c-9 to c-13 were prepared in the same manner as silane coupling agent-treated silica particles c-8.

[Preparation of antireflection films B-5 to B-6, C-12 to C-24]
(Preparation of coating solution for antireflection layer formation)
Each component is put into a mixing tank so as to have the composition shown in Table 4 below, stirred for 60 minutes, dispersed by an ultrasonic disperser for 30 minutes, and filtered through a polypropylene filter having a pore size of 5 μm to form a coating solution for forming an antireflection layer. It was.

In Table 7 below, the numerical value of each component represents the amount (parts by mass) added. The unit of the coating solution concentration is “mass%”. For the metal oxide particles and other particles, the average primary particle size, hydroxyl group equivalent, indentation hardness, and dispersion degree Cv value of the average primary particle size are described.

(Frequency of fine particles)
The frequency of the fine particles is calculated as a ratio of the numbers when all the metal oxide fine particles to be blended are regarded as having an average primary particle size. That is, for example, with respect to 1 part by weight of fine particles having an average primary particle size r1 (r1 is 120 nm to 250 nm) and specific gravity s1, fine particles having an average primary particle size r2 (r2 is 50 nm to less than 120 nm) and specific gravity s2 are X weight. In the case of partial blending, the frequency is represented by (r1 ³ · s1 · X) / (r2 ³ · s2).
Moreover, when measuring the frequency of the metal oxide particle contained in an antireflection layer, it can measure with an electron micrograph. For example, the antireflection film is observed from the surface side by SEM observation at an appropriate magnification (about 5000 times), the diameter of each of the 100 primary particles is measured, the volume is calculated, and the average of fine particles of 120 nm to 250 nm is calculated. The primary particle size can be determined as r1, and the average primary particle size of fine particles having a particle size of 50 nm or more and less than 120 nm can be determined as r2.

The compounds used are shown below.
MEK-AC-5140Z (manufactured by Nissan Chemical Co., Ltd.): methacryloyl group modification, 40% MEK dispersion of unfired silica particles having an average primary particle size of 85 nm XX-242S (manufactured by Sekisui Plastics Co., Ltd.): Crosslinked polymethyl methacrylate particles having an average primary particle size of 100 nm

Antireflection films B-5 to B-6 were prepared in the same manner as antireflection films B-1 to B-4.

Antireflection films C-12 to C-24 were produced in the same manner as the antireflection films C-1 to C-11.

(Evaluation of antireflection film)
Various characteristics of the antireflection film were evaluated by the following methods. The results are shown in Table 8.

When comparing the working samples B-2, B-5, and B-6, the combination of fine particles having an average primary particle size of 200 nm with fine particles having an average primary particle size of 50 nm or more and less than 120 nm improves the reflectance and haze, resulting in 200 nm fine particles. It can be seen that the dispersibility of is improved. Comparing the working samples C-12 to C-18, even in the case of having a hard coat, the combination of the fine particles having an average primary particle size of 210 nm and fine particles having an average primary particle size of 50 nm or more and less than 120 nm has a higher reflectance and haze. It can be seen that it is improved, and that it is particularly excellent when the particle size is 70 to 110 nm. Further, when these are compared with the working samples C-19 and C-20, it is also found that the reflectance and haze are excellent. From this result, it can be seen that those having approximately the same hydroxyl group amount and firing conditions on the surfaces of the fine particles of 210 nm and fine particles of 50 nm or more and less than 120 nm have a higher effect of suppressing aggregation than using different ones. By comparing the working samples C-16 and C-21 to C-23, it can be seen that the frequency of the fine particles of 50 nm or more and less than 120 nm with respect to the fine particles of 120 or more and 250 nm or less is best 2 to 5 times.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
The present application includes a Japanese patent application filed on March 31, 2014 (Japanese Patent Application No. 2014-074785), a Japanese patent application filed on March 31, 2014 (Japanese Patent Application No. 2014-077844), and an application filed on January 20, 2015. This is based on a Japanese patent application (Japanese Patent Application No. 2015-008713) and a Japanese patent application filed on March 23, 2015 (Japanese Patent Application No. 2015-060079), the contents of which are incorporated herein by reference.

DESCRIPTION OF SYMBOLS 1 Base material 2 Antireflection layer 3 Metal oxide particle 4 Binder resin 10 Antireflection film A Distance between the vertices of the adjacent convex portions B Distance between the centers of the adjacent convex portions and the concave portions

Claims

A substrate;
An antireflection film having an antireflection layer formed from the composition for forming an antireflection layer containing the following (A), (B) and (C),
The antireflection layer includes a binder resin including at least one of a structure derived from the following (B) and a structure derived from the following (C), and the following (on the surface opposite to the interface on the substrate side) ( A) having a moth-eye structure composed of irregularities formed of metal oxide particles of A),
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. An anti-reflection film.
(A) Metal oxide particles having a hydroxyl group on the surface and an average primary particle size of 50 nm or more and 380 nm or less.
(B) having a polymerizable group other than a (meth) acryloyl group composed of only a (meth) acryloyl group or an atom selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom as a polymerizable group; A compound having a weight average molecular weight of 1000 or less and having 3 or more polymerizable groups in the molecule.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.
The compound (C) is a carbon atom between a carbon atom constituting a carbonyl group in the (meth) acryloyl group and a silicon atom to which at least one of the hydroxyl group and the hydrolyzable group is directly bonded. The antireflection film according to claim 1, which is a compound having 4 or more.
The ratio of the number of (meth) acryloyl groups to the number of silicon atoms to which at least one of the hydroxyl group and hydrolyzable group of the compound (C) is directly bonded is 1.1 or more and 3.0 or less, The antireflection film according to claim 1 or 2.
The compound (C) is a urethane bond between a carbon atom constituting a carbonyl group in the (meth) acryloyl group and a silicon atom to which at least one of the hydroxyl group and the hydrolyzable group is directly bonded. The antireflection film according to any one of Claims 1 to 3, which is a compound having
The ratio of the mass of (C) to the sum of the mass of (B) and the mass of (C) is 0.2 or more and 0.8 or less. Antireflection film.
The antireflection film according to any one of claims 1 to 5, wherein the metal oxide particles (A) are metal oxide particles surface-modified with a compound having a (meth) acryloyl group.
The antireflection film according to any one of claims 1 to 5, wherein in the composition for forming an antireflection layer, the metal oxide particles (A) are surface-modified with the compound (C).
The antireflection film according to any one of claims 1 to 7, wherein the metal oxide particles are silica particles.
The antireflection film according to any one of claims 1 to 8, wherein the metal oxide particles are calcined silica particles.
The antireflection film according to any one of claims 1 to 9, further comprising a hard coat layer between the substrate and the antireflection layer.
A polarizing plate having a polarizer and at least one protective film for protecting the polarizer, wherein at least one of the protective films is the antireflection film according to any one of claims 1 to 10. Board.
A cover glass having the antireflection film according to any one of claims 1 to 10 as a protective film.
An image display device comprising the antireflection film according to any one of claims 1 to 10 or the polarizing plate according to claim 11.
A method for producing an antireflection film having a substrate and an antireflection layer,
The antireflection layer has a moth-eye structure having a concavo-convex shape formed of metal oxide particles of the following (A) on the surface opposite to the interface on the substrate side,
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. And
The antireflection film which has the process of apply | coating the composition for antireflection layer containing the following (A), (B) and (C) on the said base material, and hardening the following (B) and (C). Manufacturing method.
(A) Metal oxide particles having a hydroxyl group on the surface and an average primary particle size of 50 nm or more and 380 nm or less.
(B) A compound having three or more (meth) acryloyl groups in one molecule and having a weight average molecular weight of 1,000 or less. However, when the compound (B) has a polymerizable group other than the (meth) acryloyl group, the polymerizable group is a polymerization composed only of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom and an oxygen atom. Sex group.
(C) A compound having a (meth) acryloyl group and having a silicon atom to which at least one of a hydroxyl group and a hydrolyzable group is directly bonded, having a weight average molecular weight of 300 to 1,000.
An antireflection film comprising a base material, an antireflection layer containing a binder resin and metal oxide particles having an average primary particle size of 50 nm to 250 nm,
The surface of the metal oxide particles has a hydroxyl group amount of 1.00 × 10 −1 or less,
The indentation hardness of the metal oxide particles is 400 MPa or more,
The binder resin is a resin having a hydroxyl group,
The antireflection layer is an antireflection film having a moth-eye structure having a concavo-convex shape formed by the metal oxide particles on a surface opposite to the interface on the substrate side.
The concave-convex shape of the antireflection layer is such that B / A, which is a ratio of the distance A between the apexes of adjacent convex portions and the distance B between the centers of the adjacent convex portions and the concave portions, is 0.5 or more. The antireflection film according to claim 15.
The antireflection film according to claim 15 or 16, which contains only metal oxide particles having a primary particle size of 50 nm or more and 250 nm or less as the metal oxide particles.
The antireflection film according to any one of claims 15 to 17, wherein the metal oxide particles are silica particles.
The antireflection film according to any one of claims 15 to 18, wherein the metal oxide particles are calcined silica particles.
The antireflection film according to any one of claims 15 to 19, wherein the metal oxide particles are fired silica particles whose surface is modified with a compound having a (meth) acryloyl group.
The antireflection film according to claim 16, wherein the half width of the distribution of the distance A is 200 nm or less.
The binder resin is a resin obtained by polymerizing a polymerizable compound having at least one of a group having an ethylenically unsaturated double bond and an epoxy group as a polymerizable group. The antireflection film as described in 1.
The antireflection film according to claim 22, wherein the hydroxyl group equivalent of one molecule of the polymerizable compound is 1 to 10,000.
The antireflection film according to any one of claims 15 to 23, further comprising a hard coat layer between the substrate and the antireflection layer.
A polarizing plate comprising a polarizer and at least one protective film for protecting the polarizer, wherein at least one of the protective films is the antireflection film according to any one of claims 15 to 24. Board.
A cover glass having the antireflection film according to any one of claims 15 to 24 as a protective film.
An image display apparatus comprising the antireflection film according to any one of claims 15 to 24 or the polarizing plate according to claim 25.
A method for producing an antireflection film comprising a base material, and an antireflection layer containing a binder resin and metal oxide particles having an average primary particle size of 50 nm to 250 nm,
The surface of the metal oxide particles has a hydroxyl group amount of 1.00 × 10 −1 or less,
The indentation hardness of the metal oxide particles is 400 MPa or more,
The binder resin is a resin having a hydroxyl group,
The antireflection layer has a moth-eye structure consisting of a concavo-convex shape formed by the metal oxide particles on the surface opposite to the interface on the substrate side,
On the base material, a composition for forming an antireflection layer containing a polymerizable compound for forming a binder resin having a polymerizable functional group and metal oxide particles having an average primary particle size of 50 nm to 250 nm is applied. The manufacturing method of the antireflection film which has a process.
The metal oxide particles include both metal oxide fine particles having an average primary particle size of 120 nm to 250 nm and metal oxide particles having an average primary particle size of 50 nm to less than 120 nm. The antireflection film according to any one of the above.
30. The antireflection film according to claim 29, wherein the metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm have a hydroxyl group amount of 1.00 × 10 −1 or less and an indentation hardness of 400 MPa or more.
30. The antireflection film according to claim 29, wherein the metal oxide particles having an average primary particle size of 50 nm or more and less than 120 nm have a hydroxyl group content of more than 1.00 × 10 −1 or an indentation hardness of less than 400 MPa.
The metal oxide particles having an average primary particle size of not less than 120 nm and not more than 250 nm, the metal oxide particles having an average primary particle size of not less than 50 nm and less than 120 nm at a frequency of 2 to 5 times. 2. The antireflection film according to item 1.