JPWO2019065421A1 - Antireflection film, antireflection article, polarizing plate, and image display device - Google Patents

Abstract

The present invention is an antireflection film having a substrate film and an antireflection layer, wherein the antireflection layer contains metal oxide particles and a binder layer, and the binder layer is at least a specific curable compound (b-1). , A specific curable compound (b-2), and a layer obtained by curing a curable composition containing a polymerization initiator, wherein the antireflection layer has an uneven shape formed by the metal oxide particles. An antireflection film having the moth-eye structure, a polarizing plate having the antireflection film, an antireflection article, and an image display device are provided.

Description

  The present invention relates to an antireflection film, an antireflection article, a polarizing plate, and an image display device.

  Image display such as a display device using a cathode ray tube (CRT), a plasma display panel (PDP), an electroluminescence display (ELD), a fluorescent display (VFD), a field emission display (FED), and a liquid crystal display (LCD) In some devices, an anti-reflection film is provided to prevent a reduction in contrast and reflection of an image due to reflection of external light on the display surface. Further, an anti-reflection film may be provided with an anti-reflection function even in a device other than the image display device such as a glass surface of a show room.

As an anti-reflection film, an anti-reflection film having a fine unevenness whose period is equal to or less than the wavelength of visible light on a substrate surface, that is, an anti-reflection film having a so-called moth eye structure is known. The moth-eye structure can create a refractive index gradient layer in which the refractive index changes continuously from air to the bulk material inside the base material, and can prevent light reflection.
As an antireflection film having a moth-eye structure, Patent Literature 1 describes an antireflection film having a base film having an antireflection layer having a moth-eye structure composed of irregularities formed by particles.

Japanese Patent Application Laid-Open No. 2017-16065

The present inventors applied a composition for forming an antireflection layer containing metal oxide particles and a curable compound that is a compound for forming a binder layer on a base film or a hard coat layer to form a coating film, The pressure-sensitive adhesive layer was laminated on the coating film, and a part of the curable compound was diffused (penetrated) into the pressure-sensitive adhesive layer. Thereafter, the pressure-sensitive adhesive layer was peeled off to form the metal oxide particles. It has been found that an antireflection layer having a moth-eye structure composed of irregularities can be formed.
However, according to the study of the present inventors, when a part of the curable compound in the coating film formed from the composition for forming an anti-reflection layer is diffused into the pressure-sensitive adhesive layer, the metal oxide in the coating film is reduced. It has been found that the movement of the particles may reduce the regularity of the arrangement of the particles. This decrease in the regularity of the particles may lead to an increase in haze.
Patent Literature 1 does not describe a decrease in the regularity of the particles.

  It is an object of the present invention to provide an antireflection film having a moth-eye structure having an uneven shape formed by particles, the antireflection film having a high regularity of particles, a polarizing plate having the antireflection film, an antireflection article, and an image. A display device is provided.

[1]
An antireflection film having a base film and an antireflection layer,
The antireflection layer includes metal oxide particles and a binder layer,
The binder layer is a layer obtained by curing a curable composition containing at least a curable compound (b-1), a curable compound (b-2), and a polymerization initiator,
The anti-reflection film, wherein the anti-reflection layer has a moth-eye structure having an uneven shape formed by the metal oxide particles.
Curable compound (b-1): a silane coupling agent having a weight average molecular weight of 10,000 or more and having a radical reactive group. Curable compound (b-2): a molecular weight of 150 or more and having a radical reactive group. And a compound not containing silicon [2]
The antireflection film according to [1], wherein the curable composition further contains a curable compound (b-3).
Curable compound (b-3): a silane coupling agent having a molecular weight of 5000 or less and having a radical reactive group [3]
[2] The mass ratio of the content of the curable compound (b-1) to the content of the curable compound (b-3) in the curable composition is 0.05 to 0.5. The antireflection film according to the above.
[4]
An antireflection article having the antireflection film according to any one of [1] to [3] on a surface.
[5]
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 a reflection plate according to any one of [1] to [3]. A polarizing plate that is an prevention film.
[6]
An image display device comprising the antireflection film according to any one of [1] to [3] or the polarizing plate according to [5].

  According to the present invention, there is provided an antireflection film having a moth-eye structure having an uneven shape formed by particles, the antireflection film having a high regularity of particles, a polarizing plate having the antireflection film, an antireflection article, and an image display device. Can be provided.

It is a cross section showing an example of an antireflection film of the present invention. It is a schematic diagram for explaining an example of the manufacturing method of the antireflection film of the present invention.

Hereinafter, the present invention will be described in detail.
In this specification, “to” is used to mean that the numerical values described before and after it are included as the lower limit and the upper limit.
In this specification, “(meth) acrylate” is used to mean “one or both of acrylate and methacrylate”. The same applies to “(meth) acrylic group”, “(meth) acrylic acid”, “(meth) acrylamide”, “(meth) acryloyl group”, “(meth) acrylic” and the like.

The antireflection film of the present invention,
An antireflection film having a base film and an antireflection layer,
The antireflection layer includes metal oxide particles and a binder layer,
An antireflection film, wherein the binder layer is a layer obtained by curing a curable composition containing at least a curable compound (b-1), a curable compound (b-2), and a polymerization initiator.
Curable compound (b-1): a silane coupling agent having a weight average molecular weight of 10,000 or more and having a radical reactive group. Curable compound (b-2): a molecular weight of 150 or more and having a radical reactive group. And silicon-free compounds

According to the present invention, an antireflection film having a moth-eye structure composed of irregularities formed by particles, the mechanism by which an antireflection film having a high regularity of particle arrangement is provided is not completely clarified. Is estimated as follows.
The antireflection film of the present invention is, as described below, an antireflection film having an antireflection layer on a base film, wherein the antireflection layer includes metal oxide particles and a binder layer, and the binder layer is And a layer obtained by curing a curable composition described below.
The silane coupling group described below contained in the curable compound (b-1) in the curable composition forms a covalent bond with a hydroxyl group on the surface of the metal oxide particle in the antireflection layer, and the flow of the metal oxide particle And regularity of the arrangement of particles (also referred to as regularity of particles) is increased. When the weight average molecular weight of the curable compound (b-1) is 10,000 or more, the effect of suppressing aggregation of metal oxide particles can be increased.
Further, the radical polymerizable group contained in the curable compound (b-2) reacts with the radical reactive group contained in the curable compound (b-1) to be fixed, whereby the metal oxide particles are formed. Particle regularity can be improved.
Thereby, when diffusing a part of the curable compound in the coating film formed from the above-described curable composition into the pressure-sensitive adhesive layer laminated on the coating film, the metal oxide particles in the coating film Are considered to be difficult to move, and the regularity of the particles is considered to be improved.

  The antireflection film of the present invention has an integrated reflectance of preferably 3% or less over the entire wavelength range of 380 to 780 nm, more preferably 2% or less.

FIG. 1 shows an example of a preferred embodiment of the antireflection film of the present invention.
The antireflection film of the present invention may or may not include the hard coat layer.
FIG. 1 shows an antireflection film of an embodiment including a hard coat layer.
The antireflection film 10 of FIG. 1 has a base film 1, a hard coat layer HC, and an antireflection layer 2 in this order. Note that the antireflection film of the present invention may have other layers in addition to these layers. It is preferable that the hard coat layer and the antireflection layer are in contact with each other. The anti-reflection layer 2 includes metal oxide particles 3 and a binder layer 4. The metal oxide particles 3 protrude from the binder layer 4 to form an uneven shape, and the uneven shape has a moth-eye structure.

(Moss eye structure)
The anti-reflection layer of the anti-reflection film of the present invention has a moth-eye structure having an uneven shape formed by metal oxide particles.
The uneven shape is preferably formed on the surface of the antireflection layer opposite to the interface on the hard coat layer side.
The concavo-convex shape formed by the metal oxide particles is preferably such that each metal oxide particle projecting from the binder layer becomes a convex portion, and a portion where no metal oxide particles are present becomes a concave portion.
The moth-eye structure having an uneven shape indicates that the uneven shape has a moth-eye structure.
Note that other components such as a binder resin may be present on the surfaces of the metal oxide particles forming the projections as long as the moth-eye structure can be formed.
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 having a period of less than 780 nm. When the period of the fine structure pattern is less than 190 nm, the tint of the reflected light becomes small, which is preferable. Further, it is preferable that the moth-eye structure has a period of irregularities of 100 nm or more because light having a wavelength of 380 nm can recognize a fine structure pattern and has excellent 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 or not the fine structure pattern is formed.

The concavo-convex shape of the antireflection layer of the antireflection film of the present invention is a ratio B / A of the distance A between the vertices of adjacent convex portions and the distance B between the center between the vertices of adjacent convex portions and the concave portion. Is preferably 0.4 or more. When B / A is 0.4 or more, the depth of the concave portion becomes large 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 is more preferably 0.5 or more. If B / A is 0.5 or more, the distance A between the vertices of adjacent convex portions (projections formed by particles) becomes equal to or larger than the particle diameter, and concave portions are formed between the particles. As a result, both the interfacial reflection due to the portion where the refractive index changes sharply depending on the curvature on the upper side of the convex portion and the interface reflection due to the portion where the refractive index changes sharply depending on the curvature of the interparticle concave portion are present, and the Moseye It is presumed that the reflectance is more effectively reduced in addition to the refractive index gradient layer effect due to the structure.
B / A can be controlled by the volume ratio of the binder layer and the metal oxide particles in the antireflection layer. Therefore, it is important to appropriately design the mixing ratio between the binder layer and the metal oxide particles.

  Further, in order to realize a low reflectance and suppress the generation of haze, it is preferable that the metal oxide particles forming the convex portions are uniformly spread at an appropriate filling rate. From the above viewpoint, it is preferable that the content of the metal oxide particles forming the convex portions is adjusted so as to be uniform in the entire antireflection layer. The filling factor can be measured as the area occupancy (particle occupancy) of the metal oxide particles located closest to the surface when observing the metal oxide particles forming the convex portion from the surface by SEM or the like. % To 64%, more preferably 25 to 50%, even more preferably 30 to 45%.

  The uniformity of the surface of the antireflection film can be evaluated by haze. The measurement can be performed on a film sample of 40 mm × 80 mm at 25 ° C. and a relative humidity of 60% with a haze meter NDH4000 manufactured by Nippon Denshoku Industries Co., Ltd. in accordance with JIS-K7136 (2000). When the particles are aggregated and non-uniform, the haze is increased. Lower haze is preferred. The haze value is preferably from 0.0 to 3.0%, more preferably from 0.0 to 2.5%, even more preferably from 0.0 to 2.0%.

[Base film]
The base film of the antireflection film of the present invention will be described.
The base film is preferably a plastic base film. The substrate film is not particularly limited as long as it is a light-transmitting substrate generally used as a substrate film of an antireflection film. As the base film, various types can be used. For example, cellulose resins; cellulose acylate (triacetate cellulose, diacetyl cellulose, acetate butyrate cellulose); polyester resins; polyethylene terephthalate, etc., (meth) acrylic resins, polyurethane Base film containing a base resin, polycarbonate, polystyrene, olefin resin, etc., and a base film containing cellulose acylate, polyethylene terephthalate, or (meth) acrylic resin is preferable, and contains cellulose acylate. A base film is more preferred.
The thickness of the base film is generally about 10 to 1000 μm, but is preferably 15 to 200 μm, more preferably 20 to 200 μm, from the viewpoint that handleability is good, high translucency is obtained, and sufficient strength is obtained. Preferably, 20-100 μm is more preferable, and 25-100 μm is particularly preferable.
The light transmittance of the substrate film is preferably such that the total light transmittance is 80% or more, more preferably 90% or more.
The measurement of the total light transmittance shall be performed according to Japanese Industrial Standards (JIS) K7361-1 (1997).

[Anti-reflective layer]
The antireflection layer of the antireflection film of the invention will be described.
The antireflection layer includes metal oxide particles and a binder layer, and the binder layer cures a curable composition containing at least a curable compound (b-1), a curable compound (b-2), and a polymerization initiator. The anti-reflection layer has a moth-eye structure composed of irregularities formed by the metal oxide particles.
Curable compound (b-1): a silane coupling agent having a weight average molecular weight of 10,000 or more and having a radical reactive group. Curable compound (b-2): a molecular weight of 150 or more and having a radical reactive group. And silicon-free compounds

<Binder layer>
The binder layer preferably has a function of binding the metal oxide particles to the base film or the hard coat layer.

<Curable compound (b-1)>
As the curable compound (b-1), a compound having a radical reactive group is preferable. As the compound having a radical reactive group, various polymers having a weight average molecular weight of 10,000 or more can be used.
Examples of the radical reactive group include a polymerizable unsaturated group (carbon-carbon unsaturated double bond group) such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Acryloyl groups are preferred.

The silane coupling agent as the curable compound (b-1) is a compound containing a silane coupling group. The silane coupling group represents a group in which an alkoxy group or a halogen atom is bonded to a silicon atom.
Specifically, the silane coupling group is preferably represented by the following general formula (b).

In the general formula (b), R ¹ represents an alkoxy group or a halogen atom.
When R ¹ represents an alkoxy group, the alkyl group in the alkoxy group is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms.
When R ¹ represents a halogen atom, examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.
R ² represents a hydrogen atom or an organic group. Examples of the organic group include an alkyl group and an aryl group, and an alkyl group is preferable.
Examples of the alkyl group include the same alkyl group as the alkyl group in the alkoxy group when R ¹ represents an alkoxy group.
As the aryl group, an aryl group having 6 to 18 carbon atoms is preferable, an aryl group having 6 to 12 carbon atoms is more preferable, and a phenyl group is particularly preferable.
n represents an integer of 1 to 3. n is preferably 2 to 3.
* Represents a bonding position.

When a plurality of R ¹ are present, each R ¹ may be independently the same or different.
When a plurality of R ² are present, each R ² may be independently the same or different.

  Note that the silane coupling group amount indicates the number of silicon atoms to which an alkoxy group or a halogen atom is bonded.

The weight average molecular weight (Mw) of the curable compound (b-1) is preferably 10,000 to 1,000,000, more preferably 15,000 to 500,000, and still more preferably 15,000 to 100,000.
The weight average molecular weight in the present specification is a value measured by gel permeation chromatography (GPC) under the following conditions.
[Eluent] N-methyl-2-pyrrolidone (NMP)
[Device name] EcoSEC HLC-8320GPC (manufactured by Tosoh Corporation)
[Column] TSKgel SuperHZM-H, TSKgel SuperHZ4000, TSKgel SuperHZ200 (manufactured by Tosoh Corporation)
[Column temperature] 40 ° C
[Flow rate] 0.35 ml / min

The functional group equivalent (molecular weight / radical reactive group amount) in the curable compound (b-1) is preferably 450 or less, more preferably 400 or less, and even more preferably 350 or less.
The functional group equivalent represents the molecular weight per functional group, and is a value obtained by dividing the molecular weight of the curable compound (b-1) by the number of radical reactive groups.
The radical reactive group amount is the number of radical reactive groups.

The functional group equivalent of the curable compound (b-1) is preferably 50 or more, more preferably 80 or more, and preferably 100 or more.
In the curable compound (b-1), the ratio of the amount of the silane coupling group to the amount of the radical reactive group (the amount of the silane coupling group / the amount of the radical reactive group) is preferably 0.01 or more and 0.5 or less. More than 0.05 and 0.3 or less are more preferred.

In addition, the amount of the silane coupling group and the amount of the radical reactive group in the present specification are values obtained by measuring with ¹ H-NMR, respectively.

The method for synthesizing the curable compound (b-1) is not particularly limited. For example, a silane coupling agent having a radical reactive group synthesized by a known method and a monomer having a protected acryloyl group or methacryloyl group And a method of synthesizing a polymer having an acryloyl group or a methacryloyl group by introducing a silane coupling agent site into a polymer having a acryloyl group or a methacryloyl group.
The structure of the curable compound of the present invention is not particularly limited, but specific examples include polyester resin, (meth) acrylic resin, polyurethane resin, polycarbonate, polystyrene, and olefin resin. Also, dendrimers such as SIRIUS-501 and SUBARU-501 (manufactured by Osaka Organic Chemical Industry Co., Ltd.) can be preferably used.

<Curable compound (b-2)>
The curable compound (b-2) has a molecular weight of 150 or more, has a radical reactive group, and does not contain silicon. The curable compound (b-2) is preferably a compound having a radical reactive group. As the compound having a radical reactive group, various monomers, oligomers or polymers having a molecular weight of 150 or more can be used.
Examples of the radical reactive group include a polymerizable unsaturated group (carbon-carbon unsaturated double bond group) such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Acryloyl groups are preferred.

Specific examples of the compound having a polymerizable unsaturated group include (meth) acrylic acid diesters of alkylene glycols such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, and propylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyoxyalkylene glycol such as triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and polypropylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyhydric alcohols such as pentaerythritol di (meth) acrylate;
(Meth) acrylic acid diesters of ethylene oxide or propylene oxide adducts such as 2,2-bis {4- (acryloxydiethoxy) phenyl} propane and 2-2bis {4- (acryloxypolypropoxy) phenyl} propane And the like.

  Further, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates are also preferably used as the compound having a photopolymerizable group.

Among them, esters of polyhydric alcohol and (meth) acrylic acid are preferred. More preferably, it is preferable to contain at least one polyfunctional monomer having three or more (meth) acryloyl groups in one molecule.
For example, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO (ethylene oxide) modified trimethylolpropane tri (meth) acrylate, PO (propylene oxide) modified trimethylol Propane tri (meth) acrylate, EO-modified tri (meth) acrylate phosphate, trimethylolethanetri (meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) ) Acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, caprolactone-modified dipe Data erythritol Doo hexa (meth) acrylate, 1,2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate and caprolactone-modified tris (acryloyloxyethyl) isocyanurate.

  Specific examples of the polyfunctional acrylate compounds having a (meth) acryloyl group include KAYARAD DPHA, DPHA-2C, PET-30, TMPTA, TMPTA, TPA-320, and TPA- manufactured by Nippon Kayaku Co., Ltd. 330, RP-1040, T-1420, D-310, DPCA-20, DPCA-30, DPCA-60, GPO-303, V # 3PA, V manufactured by Osaka Organic Chemical Industry Co., Ltd. # 400, V # 36095D, V # 1000, V # 1080 and the like, and esterified products of (meth) acrylic acid with polyols. Also, UV-1400B, UV-1700B, UV-6300B, UV-7550B, UV-7600B, UV-7605B, UV-7610B, UV-7620EA, UV-7630B, UV-7640B UV-6630B, UV-70000B, UV-7510B, UV-7461TE, UV-3000B, UV-3200B, UV-3210EA, UV-3310EA, UV-3310B, UV-3500BA UV-3520TL, UV-3700B, UV-6100B, UV-6640B, UV-2000B, UV-2010B, UV-2250EA, UV-2750B (manufactured by Nippon Synthetic Chemical Co., Ltd.), UA-306H, UA-306I, UA-306T, UL-503L (Manufactured by Kyoeisha Chemical Co., Ltd.), Unidick 17-806, 17-813, V-4030, V-4000BA (manufactured by Dainippon Ink and Chemicals, Inc.), EB-1290K, EB-220, EB -5129, EB-1830, EB-4858 (manufactured by Daicel UCB, Ltd.), A-TMMT, AD-TMP, A-TMPT, U-4HA, U-6HA, U-10HA, U-15HA (Shin Nakamura Chemical) Industrial Corp.), Hicorp AU-2010, AU-2020 (manufactured by Tokushiki Co., Ltd.), Aronix M-1960 (manufactured by Toagosei Co., Ltd.), Art Resin UN-3320HA, UN-3320HC, UN-3320HS. , UN-904, HDP-4T and other trifunctional or higher functional urethane acrylate compounds, Aronix M-8100, M-8030, M-905 (Manufactured by Toagosei Co., Ltd., etc. KRM-8307 (manufactured by Daicel-Cytec Co.) three or more functional groups of the polyester compound, such as may also be suitably used.

  Further, resins having three or more polymerizable groups, for example, polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiro acetal resins, polybutadiene resins, polythiol polyene resins, Oligomers or prepolymers such as polyfunctional compounds such as polyhydric alcohols are also included.

  Compounds described in JP-A-2005-76005 and JP-A-2005-36105, dendrimers such as SIRIUS-501 and SUBARU-501 (manufactured by Osaka Organic Chemical Industry Co., Ltd.), and JP-A-2005-60425. The norbornene ring-containing monomer described in (1) can also be used.

The molecular weight of the curable compound (b-2) is 150 or more, preferably 200 or more, and more preferably 400 or more.
The molecular weight of the curable compound (b-2) is preferably 3,000 or less, more preferably 1,000 or less.
When the curable compound (b-2) is an oligomer or a polymer, and the molecular weight is measured by a weight average molecular weight (Mw), the above weight average molecular weight is defined as the molecular weight of the curable compound (b-2).

The mass ratio (W ₁ / W ₂ ) of the content (W ₁ ) of the curable compound (b-1) to the content (W ₂ ) of the curable compound (b- ₂ ) in the curable composition is , 0.01 to 2.0, and more preferably 0.05 to 1.0.

<Polymerizable compound (b-3)>
The curable composition preferably contains the following curable compound (b-3). Curable compound (b-3): a silane coupling agent having a molecular weight of 5,000 or less and having a radical reactive group As the curable compound (b-3), various monomers, oligomers or polymers having a molecular weight of 5,000 or less are used. Can do things.
Specific examples of the silane coupling agent having a molecular weight of 5000 or less and having a radical reactive group include, for example, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, -(Meth) acryloxypropyldimethylmethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 2- (meth) acryloxyethyltrimethoxysilane, 2- (Meth) acryloxyethyltriethoxysilane, 4- (meth) acryloxybutyltrimethoxysilane, 4- (meth) acryloxybutyltriethoxysilane and the like can be mentioned. Specifically, KBM-503, KBM-5103 (manufactured by Shin-Etsu Chemical Co., Ltd.), silane coupling agents X-12-1048, X-12-1049, X-12 described in JP-A-2014-123091. 1050 (manufactured by Shin-Etsu Chemical Co., Ltd.), and compound C3 represented by the following structural formula.

The molecular weight of the curable compound (b-3) is preferably 5,000 or less, more preferably 3,000 or less, and still more preferably 1500 or less.
The molecular weight of the curable compound (b-3) is preferably 200 or more, more preferably 250 or more, and even more preferably 300 or more.
When the curable compound (b-3) is an oligomer or a polymer and the molecular weight is measured by a weight average molecular weight (Mw), the weight average molecular weight is defined as the molecular weight of the curable compound (b-3).

The content of the above curable compound in the curable composition (b chromatography _{3) (W} 3) the curable compound to the content of _{(b-1) (W 1} ) weight ratio of _(W 1 _/ W 3) However, 0.01 to 0.5 is preferable, 0.05 to 0.5 is more preferable, and 0.05 to 0.3 is still more preferable.
By setting the mass ratio (W ₁ / W ₃ ) within the above range, the coating rate of the surface of the metal oxide particles with the curable compound while introducing an appropriate amount of the curable compound (b-1) onto the surface of the metal oxide particles. And a sufficient hardness after curing can be imparted while reducing the change in particle regularity before and after curing.

  The curable composition may further use a silane coupling agent having a reactive group other than a radical reactive group as a compound that acts to suppress aggregation of metal oxide particles described below. Specific examples of the silane coupling agent having a reactive group other than the radical reactive group include KBM-303, KBM-402, KBM-403, KBE-402, KBE-403, and KBM-4803 (Shin-Etsu Chemical Co., Ltd.) Co., Ltd.).

<Polymerization initiator>
The curable composition contains a polymerization initiator. As the polymerization initiator, an appropriate polymerization initiator may be selected depending on the type of the polymerizable compound used in combination, and a radical polymerization initiator can be suitably used. As the radical polymerization initiator, either a thermal polymerization initiator or a photopolymerization initiator may be selected according to the type of polymerization treatment (heating, light irradiation) performed in the production process. Moreover, you may use together a thermal-polymerization initiator and a photoinitiator.

  The structure of the thermal polymerization initiator is not particularly limited. Specific examples of the thermal polymerization initiator include an azo compound, a hydroxylamine ester compound, an organic peroxide, and hydrogen peroxide. Specific examples of the organic peroxide include those described in paragraph 0031 of Japanese Patent No. 5341155.

  The structure of the photopolymerization initiator is not particularly limited. Specific examples include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, fluoro Examples include amine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, coumarins, and the like. 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 are preferably used in the present invention similarly. it can.

  "Latest UV Curing Technology" {Technical Information Association Ltd.} (1991), p. 159 and "Ultraviolet curing system" by Kiyomi Kato (1989, published by the General Technology Center), p. Various examples are also described in 65 to 148 and are useful for the present invention.

  The content of the polymerization initiator in the curable composition is an amount sufficient to polymerize the polymerizable compound contained in the curable composition, and is set such that the starting point is not excessively increased. For that reason, the content is preferably 0.1 to 8% by mass, more preferably 0.5 to 5% by mass, based on the total solid content in the curable composition.

  The curable composition includes a compound that generates an acid or a base by light or heat in order to react the curable compound (b-1) and the curable compound (b-3) described above (hereinafter, a photoacid generator) , A photobase generator, a thermal acid generator, or a thermal base generator).

(solvent)
The curable composition preferably contains a solvent.
The solvent preferably contains a solvent having permeability to the base film from the viewpoint of the adhesion between the base film and the antireflection layer. The solvent having permeability to the base film is a solvent having the ability to dissolve in the base film. Here, the solvent having the ability to dissolve the base film is defined as a base film having a size of 24 mm × 36 mm (thickness: 80 μm) placed in a 15 ml bottle containing the above-mentioned solvent and placed at room temperature (25 ° C.). It means a solvent in which the base film is completely dissolved and loses its shape by allowing time to elapse and shaking the bottle appropriately.
When a cellulose acylate film is used as the base film, the permeable solvent is preferably methyl ethyl ketone (MEK), dimethyl carbonate, methyl acetate, acetone, methylene chloride, and the like. Methyl ethyl ketone (MEK), dimethyl carbonate, and methyl acetate are more preferable. Although it can be preferably used, it is not limited to these.
The composition for forming a hard coat layer may contain a solvent other than the permeable solvent (for example, ethanol, methanol, 1-butanol, isopropanol (IPA), methyl isobutyl ketone (MIBK), toluene, and the like).
In the curable composition, the content of the permeable solvent is preferably from 50% by mass to 100% by mass, and more preferably from 70% by mass to 100% by mass, based on the total mass of the solvent contained in the curable composition. % Is more preferable.
When the curable composition contains a quaternary ammonium salt-containing polymer, the curable composition preferably contains a hydrophilic solvent as a solvent from the viewpoint of compatibility with the quaternary ammonium salt-containing polymer. As the hydrophilic solvent, lower alcohols such as methanol, ethanol, isopropanol (IPA) and butanol are preferable.
The solid content concentration of the curable composition is preferably from 20% by mass to 70% by mass, more preferably from 30% by mass to 65% by mass.

<Metal oxide particles>
Examples of the metal oxide particles include silica particles, titania particles, zirconia particles, antimony pentoxide particles, and the like. And silica particles are preferred.

The average primary particle diameter of the metal oxide particles is preferably 100 nm or more and 190 nm or less, more preferably 100 nm or more and 180 nm or less, and even more preferably 100 nm or more and 170 nm or less.
As the metal oxide particles, only one type may be used, or two or more types of particles having different average primary particle sizes may be used.

  The average primary particle size of the metal oxide particles refers to a 50% particle size of the cumulative volume average particle size. A scanning electron microscope (SEM) can be used for measuring the particle size. The powder particles (in the case of a dispersion, dried and the solvent is evaporated) are observed at an appropriate magnification (about 5000 times) by SEM observation, the diameter of each of the 100 primary particles is measured, and the volume is measured. , And the cumulative 50% particle size can be used as the average primary particle size. If the particles are not spherical, the average of the major and minor diameters is taken as the diameter of the primary particles. When measuring particles contained in the anti-reflection film, the anti-reflection film is calculated by observing the anti-reflection film from the front side with the SEM as described above. At this time, the sample may be appropriately subjected to carbon vapor deposition, etching treatment, or the like to facilitate observation.

The metal oxide particles are preferably solid particles from the viewpoint of strength. The shape of the metal oxide particles is most preferably spherical, but there is no problem even if the shape is other than spherical such as amorphous.
For example, using irregular shaped particles in which a part of spherical metal oxide particles became a flat part, and suppressing the movement of the particles by placing the flat part on the lower layer side, from coating to curing through drying In each step, the aggregation of particles can be prevented, the distance between the convex portions due to the particles can be made uniform, and the transmittance in the short wavelength region can be improved, which is preferable.
As another example of the irregular shape, particles having a shape in which small particles are further bonded to a part of metal oxide particles can be used. The number of small particles bonded to the metal oxide particles may be plural, but one is more preferable. The particle size of the small particles bonded to a part of the metal oxide particles is preferably smaller than that of the metal oxide particles, more preferably 0.5 times or less the particle size of the metal oxide particles. More preferably, it is 25 times or less. The density of the small particles bonded to a part of the metal oxide particles is preferably higher than that of the metal oxide particles, more preferably 2 times or more, further preferably 3 times or more. The small particles are preferably a metal oxide, for example, zirconia, alumina, titania, and the like, and may be appropriately used as long as the above-mentioned density relationship is satisfied. For example, particles obtained by attaching zirconia particles having a particle diameter of 40 nm to silica particles having a particle diameter of 160 nm are preferable.
The silica particles may be either crystalline or amorphous.

As the metal oxide particles, it is preferable to use inorganic fine particles that have been subjected to a surface treatment in order to improve dispersibility in a coating solution, improve film strength, and prevent aggregation. Specific examples and preferable examples of the surface treatment method are the same as those described in [0119] to [0147] of JP-A-2007-298974.
The metal oxide particles are preferably particles that have been surface-modified with a compound having a polymerizable unsaturated group and a functional group reactive with the surface of the metal oxide particles.
In particular, from the viewpoint of imparting the binding property to the binder layer and improving the strength of the antireflection layer, the surface of the particles is polymerizable unsaturated group (preferably unsaturated double bond) and a functional group having reactivity with the particle surface. It is preferable that the surface is modified with a compound having a group to impart a polymerizable unsaturated group (preferably an unsaturated double bond) to the particle surface. As a compound used for surface modification, a silane coupling agent having a polymerizable group can be suitably used.
Specifically, commercially available KBM-503 and KBM-5103 (all manufactured by Shin-Etsu Chemical Co., Ltd., X-12-1048, X-12-1049, X-12-1050 described in JP-A-2014-123091) It is preferable to modify the surface of the metal oxide particles with a silane coupling agent containing a (meth) acryloyl group.

  As a specific example of the particles having an average primary particle diameter of 100 nm or more and 190 nm or less, Seahoster KE-P10 (average primary particle diameter of 150 nm, amorphous silica manufactured by Nippon Shokubai Co., Ltd.) can be preferably used.

As the metal oxide particles, calcined silica particles are particularly preferable because the amount of hydroxyl groups on the surface is moderately large and the particles are hard.
The calcined silica particles are produced by a known technique of calcining the silica particles after obtaining the silica particles by hydrolyzing and condensing a hydrolyzable silicon compound in an organic solvent containing water and a catalyst. For example, JP-A-2003-176121 and JP-A-2008-137854 can be referred to.
The silicon compound as a raw material for producing the calcined silica particles is not particularly limited, but chlorosilanes such as tetrachlorosilane, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, methylvinyldichlorosilane, trimethylchlorosilane, and methyldiphenylchlorosilane Compounds: 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 and dimethylsilanediol, diphenylsilanediol, Silanol compounds such as chill silanol; and the like. Among the silane compounds exemplified above, the alkoxysilane compound is particularly preferable because it is more easily available and the obtained calcined silica particles do not contain a halogen atom as an impurity. As a preferred form of the calcined silica particles, it is preferable that the content of halogen atoms is substantially 0% and no halogen atoms are detected.
The firing temperature is not particularly limited, but is preferably 800 to 1300C, more preferably 1000 to 1200C.
In addition, as an example of a method for producing the irregular particles, adjacent particles are sintered at the time of high-temperature sintering, and then the sintered particles are pulverized in a pulverizing step to obtain irregular particles in which a part of a spherical surface is flat. You can also.

The content of the metal oxide particles of the antireflection layer is ^{preferably 50mg / m 2 ~200mg / m 2} , more preferably ^{100mg / m 2 ~180mg / m 2} , 130mg / m 2 ~170mg / m 2 and most preferable. Above the lower limit, anti-reflection properties are more likely to be improved because a number of convex portions of the moth-eye structure can be formed, and below the upper limit, aggregation does not easily occur and a good moth-eye structure is easily formed.

  The metal oxide particles have an average primary particle diameter of 100 nm or more and 190 nm or less, and contain only one kind of monodisperse silica fine particles having a CV (coefficient of variation) value of less than 5%. And the reflectance is further reduced, which is preferable. The CV value is usually measured using a laser diffraction type particle size measuring apparatus, but other particle size measuring methods may be used, or the particle size distribution may be calculated by image analysis from the surface SEM image of the antireflection layer. it can. More preferably, the CV value is less than 4%.

In another embodiment, the metal oxide fine particles preferably include both metal oxide fine particles having an average primary particle diameter of 100 nm to 190 nm and metal oxide particles having an average primary particle diameter of 1 nm to less than 70 nm. In this case, the particles having a larger particle size mainly contribute to the moth-eye structure, and the particles having a smaller particle size are intermingled between the large particles to suppress aggregation of the large particles. As a result, the reflectance, Haze may improve. Since the metal oxide particles having a primary particle size of 1 nm or more and less than 70 nm are more immersed in the binder resin, the convex portions as the antireflection layer are formed by metal oxide fine particles having a primary particle size of 100 nm to 190 nm. Points to something. It is preferable that the frequency of the number of metal oxide particles having an average primary particle diameter of 1 nm to less than 70 nm with respect to the metal oxide fine particles having an average primary particle diameter of 100 nm to 190 nm is 1 to 3 times. Within this range, the effect of suppressing aggregation is high, and the reflectance can be lowered. The metal oxide particles having an average primary particle size of 1 nm or more and 70 nm or less are preferably 30 nm or more and 50 nm or less because the reflectance can be particularly low. When metal oxide particles having different average primary particle diameters are used in combination, it is preferable to make the amount of hydroxyl groups on the surface of both particles close to each other, because aggregation is more difficult. However, metal oxide particles having an average primary particle size of 1 nm or more and less than 100 nm are mainly used for suppressing aggregation of metal oxide particles having an average primary particle size of 100 nm or more and 190 nm or less and separating them, and therefore, they are not 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 antireflection layer may contain components other than these in addition to the binder layer and the metal oxide particles, for example, a metal oxide particle dispersant, a leveling agent, an antifouling agent and the like. Is also good.

<Dispersant for metal oxide particles>
The dispersant for the metal oxide particles reduces the cohesive force between the particles, so that the metal oxide particles can be easily arranged uniformly. The dispersant is not particularly limited, but is preferably an anionic compound such as a sulfate or a phosphate, a cationic compound such as an aliphatic amine salt or a quaternary ammonium salt, a nonionic compound, or a polymer compound. And a high molecular weight compound are more preferable because of the high degree of freedom in selecting each of a steric repulsion group and a steric repulsion group. Commercial products can also be used as the dispersant. 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.

  When the curable compound (b-1) and the curable compound (b-2) and the curable composition include the curable compound (b-3), the curable compound (b-3) is collectively referred to as “curable compound. (B) ".

<Leveling agent>
The leveling agent lowers the surface tension of the antireflection layer, thereby stabilizing the liquid after application and facilitating the uniform distribution of the curable compound (B) and the metal oxide particles.
The composition for forming an antireflection layer used in the present invention can contain at least one type of leveling agent.
This suppresses unevenness in film thickness due to unevenness in drying due to local distribution of the drying air, improves repellency of the coated product, and uniformly arranges the curable compound (B) and the metal oxide particles. Can be made easier.

  As the leveling agent, specifically, at least one type of leveling agent selected from a silicone-based leveling agent and a fluorine-based leveling agent can be used. Note that the leveling agent is preferably an oligomer or a polymer rather than a low-molecular compound.

  When the leveling agent is added, the leveling agent quickly moves to the surface of the applied coating film and is unevenly distributed, and even after the coating film is dried, the leveling agent is unevenly distributed on the surface. Surface energy is reduced by the leveling agent. From the viewpoint of preventing film thickness non-uniformity, repelling, and unevenness, it is preferable that the surface energy of the film is low.

  Preferred examples of the silicone-based leveling agent include a polymer or oligomer containing a plurality of dimethylsilyloxy units as a repeating unit and having a substituent at a terminal and / or a side chain. The polymer or oligomer containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferred. Examples of preferred substituents include groups containing a polyether group, an alkyl group, an aryl group, an aryloxy group, an aryl group, a cinnamoyl group, an oxetanyl group, a fluoroalkyl group, a polyoxyalkylene group, and the like.

  The number average molecular weight of the silicone leveling agent is not particularly limited, but is preferably 100,000 or less, more preferably 50,000 or less, particularly preferably 1,000 to 30,000, and preferably 1,000 to 20,000. Is most preferred.

  Examples of preferred silicone leveling agents include commercially available silicone leveling agents having no photopolymerizable group, such as X22-3710, X22-162C, X22-3701E, X22160AS, X22170DX, and X22015 manufactured by Shin-Etsu Chemical Co., Ltd. X22176DX, X22-176F, X224272, KF8001, X22-2000, etc .; FM4421, FM0425, FMDA26, FS1265, etc., manufactured by Chisso Corporation; BY16-750, BY16880, BY16848, SF8427, manufactured by Dow Corning Toray Co., Ltd. SF8421, SH3746, SH8400, SF3771, SH3749, SH3748, SH8410, etc .; TSF series (TS manufactured by Momentive Performance Materials Japan) 4460, TSF4440, TSF4445, TSF4450, TSF4446, TSF4453, TSF4452, TSF4730, TSF4770, etc.), FGF502, SILWET series (SILWETL77, SILWETL2780, SILWETL7608, SILWETL7001, SILWETL7002, SILWETL7087, SILWETL7200, SILWETL7210, SILWETL7220, SILWETL7230, SILWETL7500, SILWETL7510, SILWETL7600 , SILWETL7602, SILWETL7604, SILWETL7604, SILWETL7605, SILWETL7607, SILWETL7622, SILWETL7644, SILWE L7650, SILWETL7657, SILWETL8500, SILWETL8600, SILWETL8610, SILWETL8620, SILWETL720) is not limited thereto but can be exemplified.

  As those having a photopolymerizable group, X22-163A, X22-173DX, X22-163C, KF101, X22164A, X24-8201, X22174DX, X22164C, X222426, X222445, X222457, X22259, X22245 manufactured by Shin-Etsu Chemical Co., Ltd. , X221602, X221603, X22164E, X22164B, X22164C, X22164D, TM0701, etc .; Silaplane series manufactured by Chisso Corporation (FM0725, FM0721, FM7725, FM7721, FM7726, FM7727, etc.); , SF8413, BY16-152D, BY16-152, BY16-152C, 8388A, etc .; Evonik Degussa Japan Co., Ltd. TEGORad 2010, 2011, 2100, 2200N, 2300, 2500, 2600, 2700, etc .; BYK3500, manufactured by BYK Japan KK; KNS5300, manufactured by Shin-Etsu Silicone; UVHC1105, UVHC8550, manufactured by Momentive Performance Materials Japan And the like, but not limited thereto.

  The leveling agent is preferably contained in the antireflection layer in an amount of 0.01 to 5.0% by mass, more preferably 0.01 to 2.0% by mass, and more preferably 0.01 to 1.0% by mass. % Is most preferable.

The fluorine-based leveling agent is a fluoroaliphatic group and, for example, when this leveling agent is used as an additive, a coating, a amphiphilic group contributing to the affinity for various compositions such as molding materials. It is a compound having in the same molecule, and such a compound can be generally obtained by copolymerizing a monomer having a fluoroaliphatic group and a monomer having an amphiphilic group.
Representative examples of the monomer having an amphiphilic group copolymerized with the monomer having a fluoroaliphatic group include poly (oxyalkylene) acrylate, poly (oxyalkylene) methacrylate, and the like.

  Preferred commercially available fluorine-based leveling agents include those having no photopolymerizable group and manufactured by DIC Corporation, Megafac series (MCF350-5, F472, F476, F445, F444, F443, F178, F470, F475, F479). , F477, F482, F486, TF1025, F478, F178K, F-784-F, etc .; Neogent Co., Ltd. phthalgent series (FTX218, 250, 245M, 209F, 222F, 245F, 208G, 218G, 240G, 206D, 240D, etc., and those having a photopolymerizable group include Optool DAC manufactured by Daikin Industries, Ltd .; Defensa series manufactured by DIC (TF3001, TF3000, TF3004, TF3028, TF3027, TF3026). , T 3025, etc.), RS series (RS71, RS101, RS102, RS103, RS104, RS105, etc.) are exemplified but not limited thereto.

  Further, compounds described in JP-A-2004-331812 and JP-A-2004-163610 can also be used.

<Antifouling agent>
To the antireflection layer, a known silicone-based or fluorine-based antifouling agent, a slipping agent, or the like can be appropriately added for the purpose of imparting properties such as antifouling properties, water resistance, chemical resistance, and slip properties. .

  As specific examples of the silicone-based or fluorine-based antifouling agent, those having a photopolymerizable group among the aforementioned silicone-based or fluorine-based leveling agents can be suitably used, but are not limited thereto. is not.

  The antifouling agent is preferably contained in the antireflection layer in an amount of 0.01 to 5.0% by mass, more preferably 0.01 to 2.0% by mass, and more preferably 0.01 to 1.0% by mass. % Is most preferable.

  The thickness of the binder layer is preferably from 10 nm to 500 nm, more preferably from 10 nm to 300 nm, even more preferably from 20 nm to 100 nm.

Curing of the curable composition is not particularly limited, but can be performed by irradiating light. The type of light is not particularly limited, and examples thereof include X-rays, electron beams, ultraviolet light, visible light, and infrared light, and ultraviolet light is widely used. For example, if the coating film is ultraviolet-curable, preferably cured by irradiation with irradiation dose of ultraviolet rays of 10mJ ^/ cm ² ~1000mJ ^/ cm 2 by an ultraviolet lamp curable compound layer (a) and (B). More preferably ^{50mJ / cm 2 ~1000mJ / cm 2} , further preferably ^{100mJ / cm 2 ~500mJ / cm 2} . At the time of irradiation, the above energy may be applied all at once, or may be divided and applied. As the type of the ultraviolet lamp, a metal halide lamp, a high-pressure mercury lamp, or the like is suitably used.

[Hard coat layer]
The antireflection film of the present invention preferably has a hard coat layer.
The antireflection film of the present invention preferably has at least one hard coat layer between the base film and the antireflection layer.
The hard coat layer is not particularly limited, but may be, for example, a layer obtained by curing a curable compound similar to the curable compound (b-2).

(Film thickness of hard coat layer)
The thickness of the hard coat layer is preferably about 0.6 to 50 μm, more preferably 4 to 20 μm.
The strength of the hard coat layer is preferably H or more, more preferably 2H or more, in a pencil hardness test. Further, in a Taber test according to JIS K5400, the smaller the abrasion of the test piece before and after the test, the more preferable.

The antireflection film of the present invention can be used for various uses, and for example, can be suitably used as an antireflection film of an antireflection article or a polarizing plate protective film.
By applying the antireflection film of the present invention to the surface of an article, an antireflection article can be obtained. Examples of the article include transparent parts for vehicles, meters, windows, displays, substrates for touch panels, lenses, transparent substrates for solar cells, backlight unit parts, and the like.
The polarizing plate protective film using the antireflection film of the present invention can be bonded to a polarizer to form a polarizing plate, and can be suitably used for a liquid crystal display device and the like.

[Polarizer]
The polarizing plate of the present invention has a polarizer and the antireflection film of the present invention.
The polarizing plate of the present invention is a polarizing plate having a polarizer and at least one protective film for protecting the polarizer, and it is preferable that at least one of the protective films is the antireflection film of the present invention.

  Examples of the polarizer include an iodine-based polarizer, a dye-based polarizer using a dichroic dye, and a polyene-based polarizer. The iodine-based polarizer and the dye-based polarizer can be generally manufactured using a polyvinyl alcohol-based film.

[Image display device]
The image display device of the present invention has the antireflection film of the present invention or the polarizing plate of the present invention.
As an image display device, a display device using a cathode ray tube (CRT), a plasma display panel (PDP), an electroluminescence display (ELD), a fluorescent display (VFD), a field emission display (FED), and a liquid crystal display (LCD) And a liquid crystal display device is particularly preferable.
In general, a liquid crystal display device has a liquid crystal cell and two polarizing plates disposed on both sides of the liquid crystal cell, and the liquid crystal cell carries liquid crystal between two electrode substrates. Further, 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. As the liquid crystal cell, various driving liquid crystal cells such as a TN (Twisted Nematic) mode, a VA (Vertically Aligned) mode, an OCB (Optically Compensatory Bend) mode, and an IPS (In-Plane Switching) mode can be applied.

[Production method of antireflection film]
The method for producing the antireflection film of the present invention is not particularly limited, but when the antireflection film of the present invention has a hard coat layer, preferably,
A hard coat layer is provided on a substrate film, and the curable compound (B), a polymerization initiator, and metal oxide particles are provided on the hard coat layer, and the curable compound (B), a polymerization initiator (1) a step of providing the metal oxide particles in the layer (a) containing
A step (2) of laminating the layer (b) of the pressure-sensitive adhesive film having a support and a layer (b) containing a pressure-sensitive adhesive having a gel fraction of 95.0% or more on the support with the layer (a). ,
The metal oxide particles are buried in a combined layer of the layer (a) and the layer (b), and protrude from an interface of the layer (a) opposite to the interface on the hard coat layer side. (3) moving the position of the interface between the layer (a) and the layer (b) to the hard coat layer side,
Curing the layer (a) in a state where the metal oxide particles are buried in a layer obtained by combining the layer (a) and the layer (b);
A method for producing an antireflection film, comprising a step (5) of separating the layer (b) from the layer (a) in this order.

According to the above manufacturing method, the above-described antireflection film of the present invention can be manufactured.
In the above production method, the curable compound (B) described above is preferably used as the curable compound, and the aforementioned metal oxide particles are also preferably used.
The layer (a) cured in the step (4) corresponds to the binder layer described above, and the layer including the layer (a) and the metal oxide particles protruding from the layer (a) is the antireflection layer. .

FIG. 2 shows an example of a preferred embodiment of the method for producing an antireflection film of the present invention.
FIG. 2A shows a layer (a) containing a curable compound (B) and a polymerization initiator on the hard coat layer HC provided on the base film 1 in the step (1) (FIG. 4 schematically shows a state in which the metal oxide particles (reference numeral 3 in FIG. 2) are provided with a thickness embedded in the reference numeral 4).

  FIG. 2B shows a step (2) in which the support 5 and a layer (b) containing an adhesive having a gel fraction of 95.0% or more on the support 5 (reference numeral 6 in FIG. 2) 2 schematically shows a state in which the layer (b) of the pressure-sensitive adhesive film 7 having the above-mentioned is bonded to the layer (a) (reference numeral 4 in FIG. 2).

FIG. 2 (3) shows that in the step (3), the metal oxide particles are buried in the combined layer of the layer (a) and the layer (b) and the layer (a) on the hard coat layer side. The state where the position of the interface between the layer (a) and the layer (b) is moved to the hard coat layer side so as to protrude from the interface opposite to the interface is schematically illustrated. As will be described later, as a method of moving the position of the interface between the layer (a) and the layer (b) toward the hard coat layer, a part of the curable compound (B) is used as a layer (b) containing an adhesive. Method.
Moving the position of the interface between the layer (a) and the layer (b) toward the hard coat layer also means bringing the position of the interface closer to the hard coat layer.

  FIG. 2 (4) schematically shows the step (4) in which the layer (a) is cured while the metal oxide particles are buried in the combined layer (a) and the layer (b). It is represented.

  FIG. 2 (5) shows a state (antireflection film 10) after peeling the adhesive film 7 in the step (5) of peeling the adhesive film 7 including the layer (b) from the layer (a). .

  In the method for producing an antireflection film of the present invention, the temperature at which the steps (1) to (4) are performed is preferably 60 ° C or lower, more preferably 40 ° C or lower. By keeping the temperature at the time of performing the steps (1) to (4) at 60 ° C. or less, aggregation of the metal oxide particles can be suppressed, and a good uneven shape can be formed.

[Step (1)]
In the step (1), a hard coat layer is provided on a base film, and the curable compound (B), a polymerization initiator, and metal oxide particles are formed on the hard coat layer by the curable compound ( B), a step of providing the metal oxide particles in the layer (a) containing the polymerization initiator to a thickness at which the metal oxide particles are buried.
In the present invention, the “thickness in which the metal oxide particles are buried in the layer (a)” refers to a thickness of 0.8 times or more the average primary particle diameter of the metal oxide particles.

  In the step (1), the method of providing the layer (a) on the hard coat layer is not particularly limited, but is preferably provided by applying the layer (a) on the hard coat layer. In this case, the layer (a) is coated with a composition containing the curable compound (B), a polymerization initiator, and metal oxide particles (also referred to as a “composition for forming the layer (a)”). It is a layer consisting of: The application method is not particularly limited, and a known method can be used. Examples include a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, and a die coating method.

  In the step (1), it is preferable that a plurality of metal oxide particles do not exist in a direction orthogonal to the surface of the base film. Here, the absence of a plurality of metal oxide particles in the direction orthogonal to the surface of the base film means that 10 μm × 10 μm in the plane of the base film is observed with a scanning electron microscope (SEM) in three visual fields. The ratio of the number of metal oxide particles in a state where a plurality of metal oxide particles do not overlap and exist in a direction orthogonal to the surface is 80% or more, and preferably 95% or more.

(Layer (a))
The layer (a) in the step (1) preferably contains the curable compound (B), a polymerization initiator, and metal oxide particles.
The layer (a) is a layer for forming an antireflection layer.
The curable composition containing the curable compound (B) and the polymerization initiator contained in the layer (a) can be cured to become a binder layer of the antireflection layer.
The metal oxide particles contained in the layer (a) are particles that protrude from the surface of the binder layer in the antireflection film and form an uneven shape (moth-eye structure).
In addition, since the layer (a) is cured in the step (4), the components contained before and after the curing are different. . The same applies to the hard coat layer.
The thickness of the layer (a) in the step (1) is preferably 0.8 times or more and 2.0 times or less the average primary particle size of the metal oxide particles, and 0.8 times or more and 1.5 times or less. Is more preferable, and more preferably 0.9 times or more and 1.2 times or less.
As described above, since the antireflection layer is finally formed from the composition for forming the layer (a), the composition for forming the layer (a) is a composition for forming an antireflection layer. is there.

  The substrate film, hard coat layer, curable compound (B), polymerization initiator, and metal oxide particles are the same as those described above.

<Solvent>
The layer (a) or the composition for forming the layer (a) may contain a solvent.
It is preferable to select a solvent having a polarity close to that of the metal oxide particles from the viewpoint of improving dispersibility. Specifically, for example, an alcohol-based solvent is preferable, and examples thereof include methanol, ethanol, 2-propanol, 1-propanol, and butanol. Further, for example, when the metal oxide particles are metal resin particles having hydrophobic surface modification, ketone, ester, carbonate, alkane, aromatic solvents and the like are preferable, and methyl ethyl ketone (MEK), dimethyl carbonate , Methyl acetate, acetone, methylene chloride, cyclohexanone and the like. These solvents may be used as a mixture of two or more kinds as long as the dispersibility is not significantly deteriorated.

[Step (2)]
Step (2) is a step of laminating the layer (b) of the pressure-sensitive adhesive film having the support and the layer (b) containing the pressure-sensitive adhesive having a gel fraction of 95.0% or more on the support with the layer (a). It is. The method of laminating the layer (a) and the layer (b) of the pressure-sensitive adhesive film is not particularly limited, and a known method can be used, for example, a lamination method.
It is preferable that the pressure-sensitive adhesive film is bonded so that the layer (a) and the layer (b) are in contact with each other.
Before the step (2), a step of drying the layer (a) may be provided. The drying temperature of the layer (a) is preferably from 20 to 60 ° C, more preferably from 20 to 40 ° C. The drying time is preferably from 0.1 to 120 seconds, more preferably from 1 to 30 seconds.
The present inventors bonded the layer (b) and the layer (a) of the pressure-sensitive adhesive film in the step (2), and added the metal oxide particles to the layer (a) and the layer (b) in a step (3) described later. It is buried in the combined layer and protrudes from the interface of the layer (a) on the side opposite to the interface on the hard coat layer side, and in step (4) to be described later, the metal oxide particles are deposited in the layer (a) and the layer ( By hardening the layer (a) while being buried in the layer combined with the layer (b), the metal oxide particles are prevented from being exposed to the air interface before the layer (a) is hardened, so that aggregation is suppressed, and It has been found that a good concavo-convex shape formed by oxide particles can be produced.

(Adhesive film)
The pressure-sensitive adhesive film has a support and a layer (b) composed of a pressure-sensitive adhesive having a gel fraction of 95.0% or more.

<Layer (b)>
The layer (b) is made of an adhesive having a gel fraction of 95.0% or more.
When the gel fraction of the pressure-sensitive adhesive is 95.0% or more, the pressure-sensitive adhesive component is less likely to remain on the surface of the antireflection film when the pressure-sensitive adhesive film is peeled off to produce an antireflection film, and even if washing is not performed. An antireflection film having a sufficiently low reflectance can be obtained.
The gel fraction of the pressure-sensitive adhesive is preferably from 95.0% to 99.9%, more preferably from 97.0% to 99.9%, and more preferably from 98.0% to 99.9%. It is more preferred that:
The gel fraction of the pressure-sensitive adhesive is a ratio of an insoluble component after the pressure-sensitive adhesive is immersed in tetrahydrofuran (THF) at 25 ° C. for 12 hours, and is obtained from the following equation.
Gel fraction = (mass of insoluble portion of adhesive in THF) / (total mass of adhesive) × 100 (%)

The weight average molecular weight of the sol component in the pressure-sensitive adhesive is preferably 10,000 or less, more preferably 7000 or less, and most preferably 5,000 or less. When the weight average molecular weight of the sol component is in the above range, when the pressure-sensitive adhesive film is peeled off to produce an antireflection film, the pressure-sensitive adhesive component can hardly remain on the surface of the antireflection film.
The sol component of the pressure-sensitive adhesive represents a dissolved amount in THF after immersing the pressure-sensitive adhesive in tetrahydrofuran (THF) at 25 ° C. for 12 hours. The weight average molecular weight can be analyzed by gel permeation chromatography (GPC).

  The film thickness of the layer (b) is preferably from 0.1 μm to 50 μm, more preferably from 1 μm to 30 μm, even more preferably from 1 μm to 20 μm.

  The layer (b) is a pressure-sensitive adhesive layer having a slight adhesive strength with a peel strength (adhesive strength) to the surface of the adherend at a peeling speed of 0.3 m / min of about 0.03 to 0.3 N / 25 mm. It is preferable that the adhesive layer has excellent operability when the adhesive film is peeled off from the layer (a) as an adherend.

  The pressure-sensitive adhesive preferably contains a polymer, and more preferably contains a (meth) acrylic polymer. In particular, a polymer of at least one monomer of alkyl (meth) acrylate having 1 to 18 carbon atoms in the alkyl group (copolymer in the case of two or more monomers) is preferred. The weight average molecular weight of the (meth) acrylic polymer is preferably 200,000 to 2,000,000.

  Examples of the alkyl (meth) acrylate monomer having 1 to 18 carbon atoms in the alkyl group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and isobutyl (meth) acrylate. , Pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate , Decyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isomyristyl (meth) acrylate, isocetyl (meth) acrylate, isostearyl ( TA) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) Examples include alkyl (meth) acrylate monomers such as acrylate. The alkyl group of the alkyl (meth) acrylate monomer may be linear, branched, or cyclic. Two or more of the above monomers may be used in combination.

  Preferable examples of the (meth) acrylate monomer having an aliphatic ring include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, isobornyl (meth) acrylate, and the like. Among them, cyclohexyl (meth) acrylate is particularly preferred.

  The (meth) acrylic polymer is a copolymer composed of at least one alkyl (meth) acrylate monomer having an alkyl group having 1 to 18 carbon atoms and at least one other copolymerizable monomer. You may. In this case, the other copolymerizable monomer includes a copolymerizable vinyl monomer containing at least one group selected from a hydroxyl group, a carboxyl group, and an amino group, a copolymerizable vinyl monomer having a vinyl group, and an aromatic monomer. Monomers and the like.

  Examples of the hydroxyl group-containing copolymerizable vinyl monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 6-hydroxyethyl (meth) acrylate. Hydroxy group-containing (meth) acrylates such as hydroxyhexyl (meth) acrylate and 8-hydroxyoctyl (meth) acrylate, and N-hydroxy (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, and N-hydroxyethyl Hydroxyl group-containing (meth) acrylamides such as (meth) acrylamide and the like are mentioned, and it is preferable that at least one selected from these compound groups is used.

  It is preferable to contain 0.1 to 15 parts by mass of a copolymerizable vinyl monomer having a hydroxyl group based on 100 parts by mass of the (meth) acrylic polymer.

  Examples of the copolymerizable vinyl monomer containing a carboxyl group include (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, carboxyethyl (meth) acrylate, and carboxypentyl (meth) acrylate. Preferably, at least one selected from these compound groups is used.

  It is preferable to contain 0.1 to 2 parts by mass of a copolymerizable vinyl monomer having a carboxyl group based on 100 parts by mass of the (meth) acrylic copolymer.

  Examples of the copolymerizable vinyl monomer having an amino group include monomethylaminoethyl (meth) acrylate, monoethylaminoethyl (meth) acrylate, monomethylaminopropyl (meth) acrylate, and monoethylaminopropyl (meth) acrylate. Aminoalkyl (meth) acrylate and the like.

  Examples of the aromatic monomer include (meth) acrylic esters containing an aromatic group such as benzyl (meth) acrylate and phenoxyethyl (meth) acrylate, and styrene.

  Examples of the copolymerizable vinyl monomer other than those described above include various vinyl monomers such as acrylamide, acrylonitrile, methyl vinyl ether, ethyl vinyl ether, vinyl acetate, and vinyl chloride.

The pressure-sensitive adhesive may include a cured product of a composition for forming the pressure-sensitive adhesive (also referred to as a pressure-sensitive adhesive composition).
The pressure-sensitive adhesive composition preferably contains the polymer and a cross-linking agent, and may be cross-linked using heat or ultraviolet light (UV). As the cross-linking agent, one or more cross-linking agents selected from a compound group consisting of a difunctional or higher functional isocyanate cross-linking agent, a difunctional or higher functional epoxy-based cross-linking agent, and an aluminum chelate-based cross-linking agent are preferable. When a cross-linking agent is used, when the adhesive film is peeled off to produce an anti-reflection film, from the viewpoint of making the adhesive component less likely to remain on the surface of the anti-reflection film, 0.1 to 100 parts by mass of the polymer. It is preferably contained in an amount of 1 to 15 parts by mass, more preferably 3.5 to 15 parts by mass, and even more preferably 5.1 to 10 parts by mass.

The bifunctional or more isocyanate-based compound may be any polyisocyanate compound having at least two or more isocyanate (NCO) groups in one molecule. Hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate Bullet-modified diisocyanates (compounds having two NCO groups in one molecule) such as isocyanates, and isocyanurate-modified tri- or higher-valent polyols such as trimethylolpropane or glycerin (at least three in one molecule) Adducts (modified polyols) with the above compounds having an OH group).
Further, the trifunctional or more isocyanate compound is a polyisocyanate compound having at least three or more isocyanate (NCO) groups in one molecule, particularly an isocyanurate of a hexamethylene diisocyanate compound, an isocyanurate of an isophorone diisocyanate compound, It is preferably at least one selected from the group consisting of an adduct of a hexamethylene diisocyanate compound, an adduct of an isophorone diisocyanate compound, a burette of a hexamethylene diisocyanate compound, and a burette of an isophorone diisocyanate compound.
The bifunctional or more isocyanate-based crosslinking agent is preferably contained in an amount of 0.01 to 5.0 parts by mass, more preferably 0.02 to 3.0 parts by mass, based on 100 parts by mass of the polymer.

  The pressure-sensitive adhesive composition may contain an antistatic agent in order to impart antistatic performance. The antistatic agent is preferably an ionic compound, and more preferably a quaternary onium salt.

  Examples of the antistatic agent which is a quaternary onium salt include an alkyldimethylbenzylammonium salt having an alkyl group having 8 to 18 carbon atoms, a dialkylmethylbenzylammonium salt having an alkyl group having 8 to 18 carbon atoms, and an alkyl group having 8 to 18 carbon atoms. Trialkylbenzylammonium salt having an alkyl group of 18; tetraalkylammonium salt having an alkyl group having 8 to 18 carbon atoms; alkyldimethylbenzylphosphonium salt having an alkyl group having 8 to 18 carbon atoms; alkyl having 8 to 18 carbon atoms Dialkylmethylbenzylphosphonium salt having an alkyl group, trialkylbenzylphosphonium salt having an alkyl group having 8 to 18 carbon atoms, tetraalkylphosphonium salt having an alkyl group having 8 to 18 carbon atoms, having an alkyl group having 14 to 20 carbon atoms Alkyltrimethyl Ammonium salts, and the like can be used alkyldimethylethylammonium salt having an alkyl group of 14 to 20 carbon atoms. These alkyl groups may be alkenyl groups having an unsaturated bond.

Examples of the alkyl group having 8 to 18 carbon atoms include octyl, nonyl, decyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl. It may be a mixed alkyl group derived from natural fats and oils. Examples of the alkenyl group having 8 to 18 carbon atoms include octenyl, nonenyl, decenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, oleyl, and linoleyl. .
Examples of the alkyl group having 14 to 20 carbon atoms include a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, and an icosyl group. It may be a mixed alkyl group derived from natural fats and oils. Examples of the alkenyl group having 14 to 20 carbon atoms include a tetradecenyl group, a pentadecenyl group, a hexadecenyl group, a heptadecenyl group, an octadecenyl group, an oleyl group, a linoleyl group, a nonadecenyl group, and an icosenyl group.

Examples of the counter anion of the quaternary onium salt include chloride (Cl ⁻ ), bromide (Br ⁻ ), methyl sulfate (CH ₃ OSO ₃ ⁻ ), ethyl sulfate (C ₂ H ₅ OSO ₃ ⁻ ), and paratoluene sulfonate (p- CH ₃ C ₆ H ₄ SO ₃ ⁻ ) and the like.

  Specific examples of the quaternary onium salt include dodecyldimethylbenzylammonium chloride, dodecyldimethylbenzylammonium bromide, tetradecyldimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium bromide, hexadecyldimethylbenzylammonium chloride, hexadecyldimethylbenzylammonium bromide, Octadecyldimethylbenzylammonium chloride, octadecyldimethylbenzylammonium bromide, trioctylbenzylammonium chloride, trioctylbenzylammonium bromide, trioctylbenzylphosphonium chloride, trioctylbenzylphosphonium bromide, tris (decyl) benzylammonium chloride, tris (decyl) benzylan Bromide, tris (decyl) benzylphosphonium chloride, tris (decyl) benzylphosphonium bromide, tetraoctyl ammonium chloride, tetraoctyl ammonium bromide, tetraoctyl phosphonium chloride, tetraoctyl phosphonium bromide, tetranonyl ammonium chloride, tetranonyl ammonium bromide, tetra Nonylphosphonium chloride, tetranonylphosphonium bromide, tetrakis (decyl) ammonium chloride, tetrakis (decyl) ammonium bromide, tetrakis (decyl) phosphonium chloride, tetrakis (decyl) phosphonium bromide, and the like.

  Note that “tris (decyl)” and “tetrakis (decyl)” mean having three or four decyl groups which are alkyl groups having 10 carbon atoms, and tridecyl groups which are alkyl groups having 13 carbon atoms. And a tetradecyl group which is an alkyl group having 14 carbon atoms.

  As the antistatic agent, nonionic, cationic, anionic, amphoteric surfactants, ionic liquids, alkali metal salts, metal oxides, metal fine particles, conductive polymers, carbon, carbon nanotubes, and the like are also used. be able to.

  Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene fatty acid esters, glycerin fatty acid esters, propylene glycol Examples include fatty acid esters, polyoxyalkylene-modified silicones, and the like.

  Examples of the anionic surfactant include monoalkyl sulfates, alkyl polyoxyethylene sulfates, alkylbenzene sulfonates, monoalkyl phosphates, and the like.

In addition, examples of the amphoteric surfactant include alkyldimethylamine oxide and alkylcarboxybetaine.
The ionic liquid is a non-polymeric substance composed of anions and cations and liquid at normal temperature (for example, 25 ° C.). Examples of the cation moiety include a cyclic amidine ion such as an imidazolium ion, a pyridinium ion, an ammonium ion, a sulfonium ion, and a phosphonium ion. As the anion ^{_{moiety, C n H 2n + 1 COO}} -, C n F 2n + 1 COO -, NO 3 -, C n F 2n + 1 SO 3 -, (C n F 2n + 1 SO 2) 2 N -, (C n F _{2n + 1} SO ₂ ) ₃ C ⁻ , PO ₄ ²⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , AsF ₆ ⁻ , SbF ₆ ^{− and the} like.

  Examples of the alkali metal salt include a metal salt composed of lithium, sodium, and potassium, and a compound having a polyoxyalkylene structure may be added for stabilizing an ionic substance.

  The antistatic agent is preferably contained in an amount of 0.1 to 10 parts by mass based on 100 parts by mass of the polymer.

The pressure-sensitive adhesive composition may further contain a polyether-modified siloxane compound having an HLB of 7 to 15 as an antistatic auxiliary.
The HLB is a hydrophilic-lipophilic balance (hydrophilic-lipophilic ratio) defined in, for example, JIS K3211 (term of surfactant).

  The pressure-sensitive adhesive composition can further contain a crosslinking accelerator. The crosslinking accelerator may be any substance that functions as a catalyst for the reaction between the copolymer and the crosslinking agent (crosslinking reaction) when the polyisocyanate compound is used as the crosslinking agent. And organic metal compounds such as compounds, metal chelate compounds, organic tin compounds, organic lead compounds, and organic zinc compounds. In the present invention, a metal chelate compound or an organotin compound is preferable as the crosslinking accelerator.

The metal chelate compound is a compound in which one or more polydentate ligands L are bonded to a central metal atom M. The metal chelate compound may or may not have one or more monodentate ligands X attached to the metal atom M. For example, when a general formula of a metal chelate compound having one metal atom M is represented by M (L) _m (X) _n , m ≧ 1 and n ≧ 0. When m is 2 or more, m Ls may be the same ligand or different ligands. When n is 2 or more, n Xs may be the same ligand or different ligands.

  Examples of the metal atom M include Fe, Ni, Mn, Cr, V, Ti, Ru, Zn, Al, Zr, and Sn. Examples of the polydentate ligand L include β-ketoesters such as methyl acetoacetate, ethyl acetoacetate, octyl acetoacetate, oleyl acetoacetate, lauryl acetoacetate, and stearyl acetoacetate; acetylacetone (also called 2,4-pentanedione); Β-diketones such as 1,4-hexanedione and benzoylacetone. These are keto-enol tautomeric compounds, and in the multidentate ligand L, the enol may be an enolate (eg, acetylacetonate) from which the enol is deprotonated.

  Examples of the monodentate ligand X include a halogen atom such as a chlorine atom and a bromine atom, an acyloxy group such as a pentanoyl group, a hexanoyl group, a 2-ethylhexanoyl group, an octanoyl group, a nonanoyl group, a decanoyl group, a dodecanoyl group, and an octadecanoyl group. And alkoxy groups such as a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group and a butoxy group.

  Specific examples of the metal chelate compound include tris (2,4-pentanedionato) iron (III), iron trisacetylacetonate, titanium trisacetylacetonate, ruthenium trisacetylacetonate, zinc bisacetylacetonate, and aluminum trisacetone. Acetylacetonate, zirconium tetrakisacetylacetonate, tris (2,4-hexanedionato) iron (III), bis (2,4-hexanedionato) zinc, tris (2,4-hexanedionato) titanium, tris (2,4-hexanedionato) aluminum, tetrakis (2,4-hexanedionato) zirconium and the like can be mentioned.

  Examples of the organotin compound include dialkyltin oxide, dialkyltin fatty acid salts, stannous fatty acid salts, and the like. Long-chain alkyltin compounds such as dioctyltin compounds are preferred. Specific examples of the organotin compound include dioctyltin oxide, dioctyltin dilaurate, and the like.

  The crosslinking accelerator is preferably contained in an amount of 0.001 to 0.5 part by mass based on 100 parts by mass of the copolymer.

<Support>
The support in the adhesive film will be described.
As the support, a plastic film made of a resin having transparency and flexibility is preferably used. As the plastic film for the support, polyester films such as polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate and polybutylene terephthalate, (meth) acrylic resins, polycarbonate resins, polystyrene resins, and polyolefin resins are preferred. Examples of the film include a film made of a resin, a cyclic polyolefin-based resin, or a cellulose-based resin such as cellulose acylate. However, the (meth) acrylic resin includes a polymer having a lactone ring structure, a polymer having a glutaric anhydride ring structure, and a polymer having a glutarimide ring structure.
In addition, other plastic films can be used as long as they have the necessary strength and optical suitability. The support may be a non-stretched film, may be uniaxially or biaxially stretched, or may be a plastic film in which the stretching ratio or the angle of the axial method formed during the crystallization of stretching is controlled.

As the support, those having ultraviolet transmittance are preferable. When the layer (a) is cured in the step (4), it can be irradiated with ultraviolet rays from the coating layer side when the layer (a) is cured in the step (4).
Specifically, the maximum transmittance of the support at a wavelength of 250 nm to 300 nm is preferably 20% or more, more preferably 40% or more, and most preferably 60% or more. When the maximum transmittance at a wavelength of 250 nm to 300 nm is 20% or more, the layer (a) can be hardened by irradiating ultraviolet rays from the coating layer side, which is preferable.
The maximum transmittance of the pressure-sensitive adhesive film having the layer (b) formed on the support at a wavelength of 250 nm to 300 nm is preferably 20% or more, more preferably 40% or more, and still more preferably 60% or more. Is most preferred.

  The thickness of the support is not particularly limited, but is preferably from 10 μm to 100 μm, more preferably from 10 μm to 50 μm, even more preferably from 10 μm to 40 μm.

  As the pressure-sensitive adhesive film having the layer (b) formed on the support, a commercially available protective film can be suitably used. Specifically, AS3-304, AS3-305, AS3-306, AS3-307, AS3-310, AS3-0421, AS3-0520, AS3-0620, LBO-307, NBO- manufactured by Fujimori Kogyo KK 0424, ZBO-0421, S-362, TFB-4T3-367AS and the like.

  In the present invention, in the step (4), the layer (a) is cured while maintaining the state in which the metal oxide particles are buried in the combined layer of the layer (a) and the layer (b). It is preferable that the metal oxide particles have a concavo-convex shape formed by metal oxide particles protruding from the interface of the layer (a) before the step (i). Thus, after the layer (a) is cured in the step (4) and the layer (b) is peeled in the step (5), the anti-reflection in a state where the metal oxide particles project from the surface of the layer (a) A film can be obtained.

In the present invention, a step (1-2) of curing a part of the curable compound (B) in the layer (a) between the step (1) and the step (2) to obtain a cured compound (a1c). May be included.
Curing a part of the curable compound (B) means curing not a part but a part of the curable compound (B). By curing only a part of the curable compound (B) in the step (1-2), the metal oxide particles are cured in the step (3) at the interface opposite to the interface of the layer (a) on the hard coat layer side. When the position of the interface between the layer (a) and the layer (b) is moved toward the hard coat layer so as to protrude from the hard coat layer, the aggregation of particles can be suppressed, and the reflection and the total light transmittance have good antireflection. It is preferable to carry out the method because a film is obtained. Since the optimal curing conditions in the step (1-2) differ depending on the formulation of the layer (a), the optimal curing conditions may be appropriately selected.

[Step (3)]
In the step (3), the metal oxide particles are buried in the combined layer of the layer (a) and the layer (b), and the metal oxide particles are separated from the interface on the side opposite to the interface of the layer (a) on the hard coat layer side. This is a step of moving the position of the interface between the layer (a) and the layer (b) toward the hard coat layer so as to protrude.
In the present invention, "the metal oxide particles are buried in the combined layer (a) and the layer (b)" means that the thickness of the combined layer (a) and the layer (b) is a metal. It means that the average primary particle size of the oxide particles is 0.8 times or more.
Step (3) is preferably performed by allowing a part of the curable compound (B) to permeate the pressure-sensitive adhesive layer.
In the step (3), when a part of the curable compound (B) is allowed to penetrate into the pressure-sensitive adhesive layer, the laminate having the substrate film, the hard coat layer, the layer (a), and the layer (b) is heated to 60 ° C. , And more preferably 40 ° C. or lower. By keeping the temperature at 60 ° C. or less, the viscosity of the curable compound (B) and the pressure-sensitive adhesive can be kept high, and the thermal motion of the particles can be suppressed, so that the antireflection ability is reduced due to the aggregation of the particles. The effect of preventing the increase in haze and cloudiness is great. The lower limit of the temperature at which the laminate having the base film, the hard coat layer, the layer (a), and the layer (b) is kept is not particularly limited, and even at room temperature (25 ° C.), the temperature is lower than room temperature. It may be.

[Step (4)]
The step (4) is a step of curing the layer (a) in a state where the metal oxide particles are buried in the combined layer of the layer (a) and the layer (b).
In the present invention, “the state in which the metal oxide particles are buried in the layer including the layer (a) and the layer (b)” means that the thickness of the layer including the layer (a) and the layer (b) is the metal oxide. The average primary particle size of the material particles is 0.8 times or more.
Curing the layer (a) means curing the curable composition contained in the layer (a), specifically, polymerizing the curable compound (B). A binder layer in the prevention layer can be formed. By maintaining the state where the metal oxide particles are buried in the combined layer (a) and the layer (b) in the step (4), the aggregation of the metal oxide particles is suppressed, and a good uneven shape is formed. can do.
The mechanism by which the metal oxide particles are kept buried in the combined layer (a) and layer (b) to suppress the aggregation of the particles is as follows. It is known that when the particles are exposed to the air interface, a large attractive force derived from surface tension called a transverse capillary force acts, and the metal oxide particles are buried in the combined layer (a) and (b). It is presumed that the attraction can be reduced by keeping it.

Curing can be performed by irradiating light. The type of light is not particularly limited, and examples thereof include X-rays, electron beams, ultraviolet light, visible light, and infrared light, and ultraviolet light is widely used. For example, if the coating film is ultraviolet-curable, preferably cured by irradiation with irradiation dose of ultraviolet rays of 10mJ ^/ cm ² ~1000mJ ^/ cm 2 by an ultraviolet lamp curable compound layer (a) and (B). More preferably ^{50mJ / cm 2 ~1000mJ / cm 2} , further preferably ^{100mJ / cm 2 ~500mJ / cm 2} . At the time of irradiation, the above energy may be applied all at once, or may be divided and applied. As the type of the ultraviolet lamp, a metal halide lamp, a high-pressure mercury lamp, or the like is suitably used.

  The oxygen concentration during curing is preferably from 0 to 1.0% by volume, more preferably from 0 to 0.1% by volume, and most preferably from 0 to 0.05% by volume. By making the oxygen concentration at the time of curing smaller than 1.0% by volume, the film is less susceptible to curing inhibition by oxygen, and a strong film is obtained.

  In the steps (2) to (4), it is preferable that a plurality of metal oxide particles do not exist in a direction orthogonal to the surface of the base film.

In the steps (2) to (4), the total thickness of the layer (a) and the layer (b) is preferably larger than the average primary particle size of the metal oxide particles.
When the total thickness of the layer (a) and the layer (b) is larger than the average primary particle size of the metal oxide particles, the particles (a2) form the layers (a) and (b). It can be buried in the combined layer, which is preferable.
However, when the pressure-sensitive adhesive film containing the layer (b) is peeled off in the step (5) described later, a step (moth-eye structure) in which the metal oxide particles protrude from the surface of the layer (a) is obtained. )), The thickness of the layer (a) is preferably smaller than the average primary particle size of the metal oxide particles, and more preferably half or less of the average primary particle size of the metal oxide particles.
In the thickness of the layer (a) in the step (4), the height of the interface on the side opposite to the interface on the hard coat layer side of the layer (ca) obtained by curing the layer (ca) is the average of the metal oxide particles. It is preferable to adjust so as to be not more than half of the primary particle diameter. More preferably, the film cross section of the layer (ca) is observed with a scanning electron microscope (SEM), and the film thickness is arbitrarily measured at 100 points. When the average value is obtained, it is preferable to adjust the average value to be 10 nm to 100 nm (more preferably, 20 nm to 90 nm, and still more preferably, 30 nm to 70 nm).

[Step (5)]
Step (5) is a step of separating layer (b) from layer (a).
When the pressure-sensitive adhesive remains on the layer (a) side when the layer (b) is peeled off, the base film, the hard coat layer and the cured layer (a) are not dissolved, and a solvent that dissolves the pressure-sensitive adhesive is used. May be used for washing.

  After peeling off the pressure-sensitive adhesive film containing the layer (b) in the step (5), an antireflection film having a moth-eye structure composed of irregularities formed by metal oxide particles on the surface of the layer (a) is obtained.

  Hereinafter, the present invention will be described more specifically with reference to examples. The amounts, proportions, operations, and the like of the 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.

<Synthesis example 1>
(Synthesis of Curable Compound (b-1-1))
In a 500 ml three-necked flask equipped with a stirrer, a thermometer, a calcium chloride tube, and a nitrogen gas inlet tube, 20 g of Sirius-501: dendrimer-type polyfunctional acrylate (acryl equivalent: 110, manufactured by Osaka Organic Chemical Industry Co., Ltd.), methyl ethyl ketone ( MEK) (20 g), (3-mercaptopropyl) trimethoxysilane (manufactured by Tokyo Chemical Industry) (0.5 g) and triethylamine (1 mL) were added, and the mixture was stirred at room temperature for 5 hours. 200 g of MEK was added to the obtained solution, and the solution was concentrated under reduced pressure until the solid content concentration became 20% to obtain a MEK solution of the curable compound (b-1-1) of the present invention.
The weight average molecular weight (Mw) of the curable compound (b-1-1) was 30,000, and the ratio of silane coupling group amount / radical reactive group amount was 0.05.

<Synthesis Example 2>
(Synthesis of Curable Compound (b-1-2))
15 g of 2-butanone was charged into a 500 ml three-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, and heated to 84 ° C. Next, a mixed solution consisting of 30 g of BBEM (manac Co., Ltd.), 15 g of 2-butanone and 0.95 g of "V-601" (manufactured by Wako Pure Chemical Industries, Ltd.) is added such that the dripping is completed in 180 minutes. Dropped at a rapid rate. After completion of the dropwise addition, stirring was further continued for 3 hours, then the temperature was raised to 95 ° C., and stirring was continued for another 2 hours. After cooling to room temperature, 0.03 g of methylhydroquinone (manufactured by Wako Pure Chemical Industries, Ltd.), 49 g of DBU (manufactured by Wako Pure Chemical Industries, Ltd.) and 30 g of MEK were added, followed by stirring at 40 ° C. for 8 hours. After the completion of the reaction, desalting was performed by liquid separation using 1N hydrochloric acid to remove impurities. After the obtained polymer solution was dried over anhydrous magnesium sulfate and filtered, 2.1 g of (3-mercaptopropyl) trimethoxysilane (manufactured by Tokyo Chemical Industry) and 4 mL of triethylamine were added, and the mixture was stirred at room temperature for 5 hours. 200 g of MEK was added to the obtained solution, followed by concentration under reduced pressure until the solid content concentration became 20%, to obtain a MEK solution of the curable compound (b-1-2) of the present invention.
The weight average molecular weight (Mw) of the curable compound (b-1-2) was 15,000, and the ratio of the amount of the silane coupling group / the amount of the radical reactive group was 0.1.

BBEM and DBU are as follows.
BBEM: 2- (2-bromoisobutyryloxy) ethyl methacrylate DBU: diazabicycloundecene (1,8-diazabicyclo [5.4.0] undec-7-ene)

[Synthesis of Silica Particles P1]
67.54 kg of methyl alcohol and 26.33 kg of 28% by mass ammonia water (water and catalyst) were charged into a 200-L reactor equipped with a stirrer, a dropping device, and a thermometer, and the liquid temperature was adjusted to 33 ° C. while stirring. Was adjusted to On the other hand, a solution in which 12.70 kg of tetramethoxysilane was dissolved in 5.59 kg of methyl alcohol was charged into the dropping device. While maintaining the liquid temperature in the reactor at 33 ° C., the above solution was dropped from the dropping device over 37 minutes, and after completion of the dropping, the solution was stirred for another 37 minutes while maintaining the liquid temperature at the above temperature, whereby Hydrolysis and condensation of methoxysilane were performed to obtain a dispersion containing a silica particle precursor. This dispersion was flash-dried using an instantaneous vacuum evaporator (Clax System CVX-8B, manufactured by Hosokawa Micron Corp.) under the conditions of a heating tube temperature of 175 ° C. and a degree of vacuum of 200 torr (27 kPa), whereby silica particles were dried. P1 was obtained.
The average primary particle size of the silica particles P1 was 170 nm, the degree of dispersion (CV value) of the particle size was 7.0%, and the indentation hardness was 340 MPa.

[Preparation of calcined silica particles P2]
5 kg of the silica particles P1 were put in a crucible and calcined at 900 ° C. for 2 hours using an electric furnace, cooled, and then pulverized using a pulverizer to obtain pre-classified calcined silica particles. Pulverization and classification were further performed using a jet pulverizer / classifier (IDS-2, manufactured by Nippon Pneumatics Co., Ltd.) to obtain calcined silica particles P2.

[Preparation of Silane Particle P3 Treated with Silane Coupling Agent]
5 kg of the calcined silica particles P2 were charged into a 20 L Henschel mixer (Model FM20J manufactured by Mitsui Mining Co., Ltd.) equipped with a heating jacket. While the calcined silica particles P2 were being stirred, a solution of 50 g of 3-acryloxypropyltrimethoxysilane (KBM5103 manufactured by Shin-Etsu Chemical Co., Ltd.) dissolved in 90 g of methyl alcohol was dropped and mixed. Thereafter, the temperature was raised to 150 ° C. over about 1 hour with mixing and stirring, and the heat treatment was performed at 150 ° C. for 12 hours. In the heat treatment, the adhering material on the wall surface was scraped off while the scraping device was constantly rotated in the direction opposite to the stirring blade. In addition, the material adhering to the wall surface was scraped off using a spatula as appropriate. After heating, the mixture was cooled, crushed and classified using a jet pulverizing classifier, to obtain silica particles P3 treated with a silane coupling agent.
The average primary particle diameter of the silica particles P3 treated with the silane coupling agent was 171 nm, the degree of dispersion (CV value) of the particle diameter was 7.0%, and the indentation hardness was 470 MPa.

[Preparation of silica particle dispersion liquid PA-1]
50 g of silica particles P3 treated with a silane coupling agent, 200 g of MEK, and 600 g of zirconia beads having a diameter of 0.05 mm are placed in a 1 L bottle container having a diameter of 12 cm, set in a ball mill V-2M (Irie Shokai), and dispersed at 250 rpm for 10 hours. did. Thus, a silica particle dispersion liquid PA-1 (solid content concentration: 20% by mass) was produced.

[Synthesis of Compound C3]
In a flask equipped with a reflux condenser and a thermometer, 19.3 g of 3-isocyanatopropyltrimethoxysilane, 3.9 g of glycerin 1,3-bisacrylate, 6.8 g of 2-hydroxyethyl acrylate, and 0.1 g of dibutyltin dilaurate And 70.0 g of toluene were added, and the mixture was stirred at room temperature for 12 hours. After stirring, 500 ppm of methylhydroquinone was added, and the mixture was distilled under reduced pressure to obtain Compound C3.

[Synthesis of Copolymer B-1]
10.0 g of cyclohexanone was charged into a 500 ml three-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, and the temperature was raised to 84 ° C. Next, a mixed solution in which 12.8 g of 2- (perfluorohexyl) ethyl acrylate, 7.2 g of ethyl acrylate, 32 g of cyclohexanone and 0.54 g of "V-601" (manufactured by Wako Pure Chemical Industries, Ltd.) were mixed. Was dropped at a constant speed so that the dropping was completed in 180 minutes. After completion of the dropwise addition, stirring was continued for another 3 hours. Next, the temperature was raised to 95 ° C., and stirring was continued for another 2 hours to obtain a 32% by mass cyclohexanone solution of the copolymer B-1.

(Preparation of composition for forming hard coat layer)
Each component was mixed with the composition described below, and the obtained composition was put into a mixing tank, stirred, filtered through a polypropylene filter having a pore size of 0.4 μm, and filtered to form a hard coat layer forming composition (hard coat layer). Coating liquid) HC-1.

(Hard coat layer coating solution HC-1)
A-TMMT 24.4 parts by mass AD-TMP 12.0 parts by mass Irgacure 127 1.6 parts by mass Ethanol 3.5 parts by mass Methanol 8.8 parts by mass 1-butanol 6.0 parts by mass Methyl ethyl ketone (MEK) 20.3 Parts by mass Methyl acetate 21.4 parts by mass 32% by mass of cyclohexanone solution of copolymer B-1
0.8 parts by mass

A-TMMT: pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
AD-TMP: ditrimethylolpropane tetraacrylate (NK ester manufactured by Shin-Nakamura Chemical Co., Ltd.)
Irgacure 127: Photopolymerization initiator (manufactured by BASF Japan Ltd.)

[Preparation of composition (a-1) (composition for forming antireflection layer) for forming layer (a)]
Each component was charged into a mixing tank so as to have the following composition, stirred for 60 minutes, and dispersed by an ultrasonic disperser for 30 minutes to obtain a composition (a-1).

Composition of composition (a-1) U-15HA 1.2 parts by mass Compound C3 1.5 parts by mass KBM-4803 5.8 parts by mass Curable compound b-1-1 0.2 parts by mass Irgacure 127 0.2 Parts by mass Compound P 0.1 parts by mass Silica particle dispersion PA-1 32.3 parts by mass Compound A 0.1 parts by mass Ethanol 12.7 parts by mass Methyl ethyl ketone 33.3 parts by mass Acetone 12.7 parts by mass

U-15HA, compound C3 and KBM-4803 are compounds for binders, while U-15HA is a curable compound (b-2), compound C3 is a curable compound (b-3), and KBM- 4803 is a silane coupling agent having a reactive group other than the radical reactive group.
The compounds used are shown below.
U-15HA (manufactured by Shin-Nakamura Chemical Co., Ltd.): urethane acrylate Irgacure 127: photopolymerization initiator (manufactured by BASF Japan Ltd.)
Compound P: 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine (photoacid generator, manufactured by Tokyo Chemical Industry Co., Ltd.)
Compound A: F-784-F (manufactured by DIC Corporation)
KBM-4803: a silane coupling agent having a reactive group other than a radical reactive group (manufactured by Shin-Etsu Chemical Co., Ltd.)

[Preparation of composition (a-2) for forming layer (a)]
Each component was put into a mixing tank so as to have the following composition, stirred for 60 minutes, and dispersed by an ultrasonic disperser for 30 minutes to obtain a composition (a-2).
Composition of composition (a-2) U-15HA 1.4 parts by mass Compound C3 1.5 parts by mass KBM-4803 5.8 parts by mass Curable compound b-1-2 0.14 parts by mass Irgacure 127 0.2 Parts by mass Compound P 0.1 parts by mass Silica particle dispersion PA-1 32.3 parts by mass Compound A 0.1 parts by mass Ethanol 12.7 parts by mass Methyl ethyl ketone 33.3 parts by mass Acetone 12.7 parts by mass

[Preparation of composition (a-3) for forming layer (a)]
Each component was put into a mixing tank so as to have the following composition, stirred for 60 minutes, and dispersed by an ultrasonic disperser for 30 minutes to obtain a composition (a-3).
Composition of composition (a-3) U-15HA 1.0 part by mass Compound C3 1.6 parts by mass KBM-4803 5.8 parts by mass Compound b-1-1 1.0 part by mass Irgacure 127 0.2 parts by mass Compound P 0.1 parts by mass Silica particle dispersion PA-1 32.3 parts by mass Compound A 0.1 parts by mass Ethanol 12.7 parts by mass Methyl ethyl ketone 33.3 parts by mass Acetone 12.7 parts by mass

[Preparation of composition (a-4) for forming layer (a)]
Each component was charged into a mixing tank so as to have the following composition, stirred for 60 minutes, and dispersed by an ultrasonic disperser for 30 minutes to obtain composition (a-4).
Composition of composition (a-4) U-15HA 1.5 parts by mass Compound C3 2.4 parts by mass KBM-4803 5.8 parts by mass Compound b-1-2 0.05 parts by mass Irgacure 127 0.2 parts by mass Compound P 0.1 parts by mass Silica particle dispersion PA-1 32.3 parts by mass Compound A 0.1 parts by mass Ethanol 12.7 parts by mass Methyl ethyl ketone 33.3 parts by mass Acetone 12.7 parts by mass

[Preparation of composition (a-5) for forming layer (a)]
Each component was put into a mixing tank so as to have the following composition, stirred for 60 minutes, and dispersed by an ultrasonic disperser for 30 minutes to obtain a composition (a-5).
Composition of composition (a-5) U-15HA 1.0 part by mass Compound C3 1.4 parts by mass KBM-4803 5.8 parts by mass Curable compound b-1-1 0.35 parts by mass Irgacure 127 0.2 Parts by mass Compound P 0.1 parts by mass Silica particle dispersion PA-1 32.3 parts by mass Compound A 0.1 parts by mass Ethanol 12.7 parts by mass Methyl ethyl ketone 33.3 parts by mass Acetone 12.7 parts by mass

[Preparation of composition (c-1) for forming layer (a)]
Each component was put into a mixing tank so as to have the following composition, stirred for 60 minutes, and dispersed by an ultrasonic disperser for 30 minutes to obtain a composition (c-1).
Composition of composition (c-1) U-15HA 1.4 parts by mass Compound C3 1.5 parts by mass KBM-4803 5.8 parts by mass Irgacure 127 0.2 parts by mass Compound P 0.1 parts by mass Silica particle dispersion PA-1 32.3 parts by mass Compound A 0.1 part by mass Ethanol 12.7 parts by mass Methyl ethyl ketone 33.3 parts by mass Acetone 12.7 parts by mass

Example 1
<Preparation of antireflection film 1>
(Formation of hard coat layer)
A hard coat layer coating solution HC-1 was applied on a base film (TJ25, manufactured by Fuji Film Co., Ltd.) using a die coater. After drying at 30 ° C. for 90 seconds and then at 45 ° C. for 1 minute, an air-cooled metal halide lamp of 160 W / cm (Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of about 1.3% by volume. The coating layer was cured by irradiating ultraviolet rays having an illuminance of 18 mW / cm ² and an irradiation amount of 10 mJ / cm ² to form a hard coat layer having a thickness of 5 μm. The substrate with a hard coat layer is referred to as HC-1.

(Step (1) Coating of Layer (a))
The composition (a-1) was applied on the hard coat layer of the base material with a hard coat layer HC-1 using a die coater at 2.8 ml / m ^{2 and} dried at 30 ° C. for 90 seconds. The film thickness of the layer (a) in the step (1) is 170 nm.

(Step (1-2) a step of curing a part of the curable compound (B) in the layer (a) to obtain a cured compound (a1c))
Using a high-pressure mercury lamp (Model: 33351N manufactured by Dr. honle AG, part number: LAMP-HOZ 200 D24 U 450 E) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.4% by volume, the layer (a) ) Side was irradiated with light at an irradiation amount of 5.0 mJ to cure a part of the curable compound (B). In addition, the measurement of the irradiation amount is performed using a HEAD SENSER with an eye ultraviolet integrating illuminometer UV METER UVPF-A1 manufactured by Eye Graphic Co., Ltd.
PD-365 was attached, and the measurement was performed with a measurement range of 0.00.

(Process (2) Lamination of adhesive film)
Next, on the dried layer (a), an adhesive film obtained by peeling the release film from AS3-304 was attached so that the adhesive layer (layer (b)) was on the layer (a) side. . Lamination was performed at a speed of 1 using a commercial laminator Bio330 (manufactured by DAE-EL Co.).
Note that AS3-304 indicates a laminate (protective film) composed of a support / adhesive layer / peeling film, and a laminate composed of a support / adhesive layer obtained by peeling the release film from the laminate. The body is an adhesive film.

Details of the laminate (protective film) used are shown below.
・ AS3-304 Fujimori Industry Co., Ltd. Support: polyester film (38 μm thickness)
Adhesive layer thickness: 20 μm
Maximum transmittance at a wavelength of 250 nm to 300 nm with the release film peeled off: less than 0.1% The transmittance was measured using a UV-visible / near-infrared spectrophotometer UV3150 manufactured by Shimadzu Corporation.

(Step (3) Penetration of the curable compound (B) into the pressure-sensitive adhesive layer)
With the adhesive film adhered, the mixture was allowed to stand at 25 ° C. for 5 minutes to allow a part of the curable compound (B) to permeate the adhesive layer.

(Step (4) Curing of Layer (a))
Subsequent to the above standing, a substrate film was formed using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.01% by volume or less. UV light having an illuminance of 150 mW / cm ² and an irradiation amount of 600 mJ / cm ² was irradiated from the surface to which the layer (a) was applied through the adhesive film to cure the layer (a). After the step (4) and before the step (5), the layer (a) and the pressure-sensitive adhesive layer (layer (b)) had a thickness of 50 nm and 20 μm, respectively.

(Step (5) Peeling of the adhesive film)
The pressure-sensitive adhesive film (layer obtained by peeling the release film from AS3-304) containing the layer (b) was peeled off from the laminate produced above. After the layer (b) was peeled off, the layer (a) was cured to such an extent that the layer (a) was not broken by the peeling of the pressure-sensitive adhesive layer. After the pressure-sensitive adhesive is peeled off, the layer of the plastic substrate is formed using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the atmosphere has an oxygen concentration of 0.01% by volume or less. The layer (a) was cured by irradiating ultraviolet light having an illuminance of 150 mW / cm ² and an irradiation amount of 600 mJ / cm ² from the surface to which (a) was applied. Thereafter, methyl isobutyl ketone was poured over the surface to which the adhesive film was attached to wash away the residue of the adhesive layer, and dried at 25 ° C. for 10 minutes to obtain an antireflection film 1.

（Δ粒子規則性）＝（基準用サンプル１の粒子規則性）−（反射防止フィルム１の粒子規則性）
Δ粒子規則性は以下の基準で評価した。
Ａ：４％未満
Ｂ：４％以上８％未満
Ｃ：８％以上１０％未満
Ｄ：１０％以上
なお、Ｃ以上であれば、実用的に問題はない。(Regularity of particles)
The regularity of the particles was evaluated based on how much the regularity of the particles changed from the reference sample (sample for reference) (Δ regularity of particles).
-Preparation of reference sample 1-
A sample which has been subjected to the step (1-2) of the anti-reflection film 1 is prepared, and an air-cooled metal halide lamp of 160 W / cm (Eye Graphics Co., Ltd. )), The layer (a) is cured by irradiating an ultraviolet ray having an illuminance of 150 mW / cm ² and an irradiation amount of 600 mJ / cm ² from the surface of the substrate film on which the layer (a) is applied, thereby curing the layer (a). Sample 1 was prepared.
−Calculation of particle regularity−
The surface of the obtained antireflection film 1 and reference sample 1 was observed by SEM (S-4300 manufactured by Hitachi High-Technologies Corporation). The number of particles in the range of 1280 nm × 830 nm and the average center-to-center distance to the nearest particle were calculated, and the regularity of the particles was calculated by the following equation.
(Particle regularity)
= (Average center-to-center distance to nearest particle-average primary particle size) / (inter-particle distance in close packing-average primary particle size) x 100
Here, the distance between the particles in the closest packing is represented by the following equation.

(Δ particle regularity) = (particle regularity of reference sample 1) − (particle regularity of antireflection film 1)
The Δ particle regularity was evaluated according to the following criteria.
A: less than 4% B: 4% or more and less than 8% C: 8% or more and less than 10% D: 10% or more There is no practical problem if it is C or more.

Described in Table 1 also _{W 1 / W 3, W 1} / W 2.

<Examples 2 to 5 and Comparative Example 1>
Antireflection films 2 to 5 and C1 were prepared and evaluated in the same manner as in Example 1 except that the types of compositions shown in Table 1 below were used instead of the composition (a-1).
The antireflection films 2 to 5 and the reference samples 2 to 5 and C1 corresponding to C1 were prepared in the same manner as the reference sample 1 except that a sample that had passed through each antireflection film step (1-2) was prepared. Created. Δ particle regularity was calculated by subtracting the particle regularity of each antireflection film from the particle regularity of each reference sample, as shown in the following formula.
(Δ particle regularity) = (particle regularity of reference sample) − (particle regularity of antireflection film)

Described in Table 1 also _{W 1 / W 3, W 1} / W 2.

  The evaluation results are shown in Table 2 below.

Comparison of Examples 1 to 5 with Comparative Example 1 showed that the antireflection films of Examples 1 to 5 had low reduction in particle regularity.
As a result of comparison between Examples 1 to 2, 5 and 3 to 4, the antireflection films of Examples 1 to 2 and 5 showed that the reduction in particle regularity was even lower.

  According to the present invention, there is provided an antireflection film having a moth-eye structure composed of irregularities formed by particles, the antireflection film having a high regularity of particles, a polarizing plate having the antireflection film, an antireflection article, and an image. A display device can be provided.

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.
This application is based on Japanese Patent Application (No. 2017-191515) filed on September 29, 2017, the contents of which are incorporated herein by reference.

Reference Signs List 1 base film HC hard coat layer 2 antireflection layer 3 metal oxide particle 4 binder layer (layer (a))
5 support 6 layers (b)
7 Adhesive film 10 Anti-reflection film A Distance between vertices of adjacent convex parts B Distance between center and concave part between vertices of adjacent convex parts UV Ultraviolet

Claims (6)

An antireflection film having a base film and an antireflection layer,
The antireflection layer includes metal oxide particles and a binder layer,
The binder layer is a layer obtained by curing a curable composition containing at least a curable compound (b-1), a curable compound (b-2), and a polymerization initiator,
The anti-reflection film, wherein the anti-reflection layer has a moth-eye structure having an uneven shape formed by the metal oxide particles.
Curable compound (b-1): a silane coupling agent having a weight average molecular weight of 10,000 or more and having a radical reactive group. Curable compound (b-2): a molecular weight of 150 or more and having a radical reactive group. And silicon-free compounds The anti-reflection film according to claim 1, wherein the curable composition further contains a curable compound (b-3).
Curable compound (b-3): a silane coupling agent having a molecular weight of 5000 or less and having a radical reactive group   The mass ratio of the content of the curable compound (b-1) to the content of the curable compound (b-3) in the curable composition is from 0.05 to 0.5. The antireflection film according to the above.   An antireflection article having the antireflection film according to claim 1 on a surface.   It is a polarizing plate which has a polarizer and at least one protective film which protects the polarizer, and at least one of the protective films is the antireflection film according to any one of claims 1 to 3. Polarizing plate.   An image display device comprising the antireflection film according to claim 1 or the polarizing plate according to claim 5.

Images