JP5933353B2 - Antireflection film, method for producing the same, polarizing plate, and image display device - Google Patents

Description

  The present invention relates to an antireflection film, a production method thereof, a polarizing plate using the antireflection film, and an image display device using the antireflection film or the polarizing plate on the outermost surface of a display.

In general, an antireflection film is used in an image display device such as a cathode ray tube display (CRT), plasma display (PDP), electroluminescence display (ELD), liquid crystal display (LCD), etc. In order to prevent reflection of light, it is disposed on the outermost surface of the display so as to reduce the reflectance. Therefore, in addition to high antireflection performance, the antireflection film has high antifouling properties against oil and fat components such as fingerprints and sebum, and high physical strength (such as scratch resistance), high transmittance, chemical resistance, and weather resistance ( Resistance to moisture and heat).
As such an antireflection film, a film having a single optical interference layer is known. In addition, from the viewpoint of achieving further low reflection, multilayer antireflection films having a plurality of optical interference layers such as a low refractive index layer, a middle refractive index layer, and a high refractive index layer are also being developed. It is.
For example, in Patent Documents 1 to 4, each layer is formed by applying and curing a composition containing a polyfunctional curable compound, and for adjusting the refractive index, the medium refractive index layer and the high refractive index layer are oxidized. A multilayer antireflection film containing fine particles such as titanium is described.
Such a multilayer antireflection film can achieve low reflection, but the reflection color may change when the film thickness or refractive index of each layer varies.
Thus, from the viewpoint of suppressing fluctuations in the film thickness of each layer, for example, it is known that a leveling agent is included in applying a low refractive index layer to suppress film thickness unevenness (see, for example, Patent Document 5).

JP 2005-283730 A Japanese Patent Laid-Open No. 10-300902 JP 2003-75603 A JP 2001-31871 A JP 2012-36394 A

However, when a leveling agent is contained in an intermediate layer such as a medium refractive index layer or a high refractive index layer, when the layering is performed on the layer containing the leveling agent, the leveling agent is unevenly distributed at the interface, The adhesion (interfacial bondability) of the film deteriorates, the interface is easily peeled off (prone to scratches), and the problem of poor scratch resistance occurs. In addition, when a polarizing plate is further produced from the obtained multilayer antireflection film, the saponification treatment causes decomposition of the bonding group of the binder, so that the interface is easily peeled off (prone to scratches). The problem of inferior scratching becomes even more pronounced. From such a point of view, a leveling agent having a high leveling property is not contained in the middle refractive index layer, and saponification without a protective film (laminate film) has not been performed.
In view of the above-mentioned problems of the prior art, the object of the present invention is excellent in scratch resistance even after saponification, and does not require a protective film (laminate film) in the saponification, There is provided an antireflection film, a polarizing plate using the antireflection film, and an image display device.

上記一般式１において、Ｒ ^１ は水素原子、ハロゲン原子又はメチル基を表す。
Ｘは酸素原子、イオウ原子又は−Ｎ（Ｒ ^１２ ）−を表す。Ｒ ^１２ は水素原子又は炭素数１〜８のアルキル基を表す。Ｒ _ｆ は−ＣＦ _３ 又は−ＣＦ _２ Ｈを表す。
ｍは１〜６の整数を表す。
ｎは１〜１１の整数を表す。
＜２＞
前記一般式１において、Ｒ _ｆ は−ＣＦ _３ を表す＜１＞に記載の反射防止フィルム。
＜３＞
前記平均１次粒子径１０ｎｍ未満の有機又は無機粒子（Ａ）がジルコニア粒子である、＜１＞又は＜２＞に記載の反射防止フィルム。
＜４＞
前記不飽和二重結合を３つ以上有する化合物（Ｂ）の分子量の数値を、官能基数で除した値である、分子量／官能基数が１００以下である、＜１＞〜＜３＞のいずれか１項に記載の反射防止フィルム。
＜５＞
前記透明支持体がセルロースアシレートフィルムである、＜１＞〜＜４＞のいずれか１項に記載の反射防止フィルム。
＜６＞
偏光膜と該偏光膜の両面を保護する２枚の保護フィルムを有する偏光板であって、該保護フィルムの少なくとも一方が＜１＞〜＜５＞のいずれか１項に記載の反射防止フィルムである偏光板。
＜７＞
＜１＞〜＜５＞のいずれか１項に記載の反射防止フィルム、又は＜６＞に記載の偏光板を有する画像表示装置。
＜８＞
透明支持体上にハードコート層、中屈折率層、高屈折率層及び低屈折率層をこの順に有し、各層それぞれが塗布、乾燥及び硬化の工程を行うことで形成される反射防止フィルムの製造方法であって、前記中屈折率層が（Ａ）平均１次粒子径１０ｎｍ未満の有機又は無機粒子、（Ｂ）不飽和二重結合を３つ以上有する化合物、（Ｃ）下記一般式１で表されるモノマーに相当する繰り返し単位を有する重合体を含有する組成物から形成され、前記重合体（Ｃ）が前記組成物中の全固形分に対して１．０〜２．０質量％であり、前記有機又は無機粒子（Ａ）が、前記組成物中の全固形分に対して３０〜６０質量％である、反射防止フィルムの製造方法。
一般式１

上記一般式１において、Ｒ ^１ は水素原子、ハロゲン原子又はメチル基を表す。
Ｘは酸素原子、イオウ原子又は−Ｎ（Ｒ ^１２ ）−を表す。Ｒ ^１２ は水素原子又は炭素数１〜８のアルキル基を表す。Ｒ _ｆ は−ＣＦ _３ 又は−ＣＦ _２ Ｈを表す。
ｍは１〜６の整数を表す。
ｎは１〜１１の整数を表す。
＜９＞
前記一般式１において、Ｒ _ｆ は−ＣＦ _３ を表す＜８＞に記載の反射防止フィルムの製造方法。
＜１０＞
前記塗布、乾燥及び硬化の工程の後、さらに鹸化処理を行う、＜８＞又は＜９＞に記載の反射防止フィルムの製造方法。
なお、本発明は上記＜１＞〜＜１０＞に関するものであるが、参考のためその他の事項（下記〔１〕〜〔７〕に記載した事項等）についても記載した。
As a result of intensive studies to solve the above problems, the present inventors have determined the content of the particles in the layer by making the average primary particle diameter of the organic or inorganic particles in the medium refractive index layer less than 10 nm. By increasing the surface area of the particles without change, a specific hydrophobic leveling agent (polymer containing a repeating unit corresponding to the monomer represented by the general formula 1) is unevenly distributed and concentrated on the surface of the medium refractive index layer. It is considered that the concentration of the bonding group of the binder (a compound having three or more unsaturated double bonds) in the vicinity of the surface of the layer can be increased. As a result, it was found that the bondability with the upper layer was improved, and good scratch resistance could be achieved even after the saponification treatment. Based on the above findings, the present invention has been completed.
<1>
An antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer and a low refractive index layer in this order on a transparent support, wherein the medium refractive index layer (A) has an average primary particle diameter of less than 10 nm An organic or inorganic particle, (B) a compound having three or more unsaturated double bonds, and (C) a composition containing a polymer having a repeating unit corresponding to the monomer represented by the following general formula 1. The polymer (C) is 1.0 to 2.0% by mass with respect to the total solid content in the composition, and the organic or inorganic particles (A) are the total solid content in the composition. The antireflection film which is 30 to 60% by mass relative to the mass.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.
<2>
In Formula 1, the antireflection film according to <1> _{R f} is representative of the -CF _3.
<3>
The antireflection film according to <1> or <2>, wherein the organic or inorganic particles (A) having an average primary particle diameter of less than 10 nm are zirconia particles.
<4>
Any one of <1> to <3>, wherein the molecular weight / functional group number is 100 or less, which is a value obtained by dividing the numerical value of the molecular weight of the compound (B) having three or more unsaturated double bonds by the number of functional groups 2. The antireflection film according to item 1.
<5>
The antireflection film according to any one of <1> to <4>, wherein the transparent support is a cellulose acylate film.
<6>
It is a polarizing plate which has two protective films which protect both surfaces of a polarizing film and this polarizing film, Comprising: At least one of this protective film is an antireflection film in any one of <1>-<5> A polarizing plate.
<7>
<1>-<5> The image display apparatus which has an antireflection film of any one of <5>, or a polarizing plate as described in <6>.
<8>
An antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer, and a low refractive index layer in this order on a transparent support, and each layer is formed by applying, drying and curing steps. A production method, wherein the medium refractive index layer is (A) organic or inorganic particles having an average primary particle diameter of less than 10 nm, (B) a compound having three or more unsaturated double bonds, (C) the following general formula 1 Formed from a composition containing a polymer having a repeating unit corresponding to the monomer represented by formula (1), wherein the polymer (C) is 1.0 to 2.0% by mass with respect to the total solid content in the composition. The method for producing an antireflection film, wherein the organic or inorganic particles (A) are 30 to 60% by mass with respect to the total solid content in the composition.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.
<9>
In Formula 1, _{R f} is a manufacturing method of the antireflection film as described in <8> representing a -CF _3.
<10>
The method for producing an antireflection film according to <8> or <9>, wherein a saponification treatment is further performed after the coating, drying, and curing steps.
The present invention relates to the above <1> to <10>, but other matters (items described in [1] to [7] below) are also described for reference.

[1]
An antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer and a low refractive index layer in this order on a transparent support, wherein the medium refractive index layer (A) has an average primary particle diameter of less than 10 nm An organic or inorganic particle, (B) a compound having three or more unsaturated double bonds, and (C) a composition containing a polymer having a repeating unit corresponding to the monomer represented by the following general formula 1. The polymer (C) is 0.2 to 2.0% by mass with respect to the total solid content in the composition, and the organic or inorganic particles (A) are the total solid content in the composition. The antireflective film which is 30-60 mass% with respect to.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.
[2]
The antireflection film according to [1], wherein the organic or inorganic particles (A) having an average primary particle diameter of less than 10 nm are zirconium oxide particles.
[3]
The molecular weight / number of functional groups is 100 or less, which is a value obtained by dividing the numerical value of the molecular weight of the compound (B) having three or more unsaturated double bonds by the number of functional groups, according to [1] or [2] Antireflection film.
[4]
The antireflection film according to any one of [1] to [3], wherein the transparent support is a cellulose acylate film.
[5]
It is a polarizing plate which has two protective films which protect both surfaces of a polarizing film and this polarizing film, Comprising: At least one of this protective film is an antireflection film in any one of [1]-[4] A polarizing plate.
[6]
An image display device comprising the antireflection film according to any one of [1] to [4] or the polarizing plate according to [5].
[7]
An antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer, and a low refractive index layer in this order on a transparent support, and each layer is formed by applying, drying and curing steps. In the production method, the medium refractive index layer is (A) an organic or inorganic particle having an average primary particle diameter of less than 10 nm, (B) a compound having three or more unsaturated double bonds, (C) It is formed from a composition containing a polymer having a repeating unit corresponding to the monomer represented, and the polymer (C) is 0.2 to 2.0 mass% with respect to the total solid content in the composition. Yes, The manufacturing method of the anti-reflective film whose said organic or inorganic particle (A) is 30-60 mass% with respect to the total solid in the said composition.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.

Since the antireflection film of the present invention is excellent in scratch resistance even after saponification treatment, a protective film (laminate film) is not required in the saponification treatment, and the production cost can be reduced. Moreover, since there is little film thickness nonuniformity, the favorable antireflection film without a color nonuniformity can be obtained.
According to the antireflection film of the present invention, it is possible to provide a polarizing plate and an image display device that are excellent in scratch resistance even after saponification treatment and have no uneven coloring.

It is sectional drawing which shows typically the laminated constitution of the antireflection film of this invention.

  The present invention will be described below. However, the present invention is not limited by the following description. In the present specification, when a numerical value represents a physical property value, a characteristic value, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”. . In the present specification, the description “(meth) acrylate” means “at least one of acrylate and methacrylate”. The same applies to “(meth) acryloyl group”, “(meth) acrylic acid” and the like.

The antireflective film of the present invention is an antireflective film having a hard coat layer, a medium refractive index layer, a high refractive index layer and a low refractive index layer in this order on a transparent support, wherein the medium refractive index layer is (A ) An organic or inorganic particle having an average primary particle diameter of less than 10 nm, (B) a compound having three or more unsaturated double bonds, and (C) a weight having a repeating unit corresponding to the monomer represented by the following general formula 1. Formed from a composition containing coalesced, the polymer (C) is 0.2 to 2.0 mass% with respect to the total solid content in the composition, the organic or inorganic particles (A), It is 30-60 mass% with respect to the total solid in the said composition.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.

<(A) Organic or inorganic nanoparticles having an average primary particle diameter of less than 10 nm>
In the present invention, the composition for forming the medium refractive index layer (hereinafter, also simply referred to as “medium refractive index layer forming composition”) contains organic or inorganic particles (A) having an average primary particle diameter of less than 10 nm. The organic or inorganic particles (A) are 30 to 60% by mass with respect to the total solid content in the composition.

(Inorganic particles)
The inorganic particles are preferably metal (eg, Zr, Ti, In, Zn, Sn, Sb, Al) oxides, more preferably zirconium oxide particles (ZrO ₂ ) or titanium oxide particles (TiO ₂ ). Preferably, when the titanium oxide particles have an average primary particle diameter of less than 10 nm, the photoactivity is enhanced, and the zirconium oxide particles (zirconia particles) are most preferable from the viewpoint that the surrounding organic matter can be easily decomposed and the refractive index described later. .

(Organic particles)
As organic particles, for example, spherical polymers such as triazine, polystyrene, benzoguanamine-formaldehyde condensate, melamine-formaldehyde condensate are preferable, and triazine spherical polymer is more preferable.

The average primary particle diameter of the organic or inorganic particles in the medium refractive index layer is preferably 1 to 8 nm, and more preferably 2 to 7 nm. Within this range, by increasing the surface area of the particles without changing the content of the particles in the layer, the bonding group of the binder near the layer surface (compound having three or more unsaturated double bonds) The concentration is increased, and the adhesion with the upper layer is improved, which is preferable.
In the present invention, the average primary particle size can be calculated by observing randomly selected particles with an electron microscope. In the present invention, 400 arbitrary particles contained in the medium refractive index layer are selected, the particle size distribution of these particles (particle number distribution with respect to the particle size) is determined, and the average particle size at which the number of particles reaches a peak It is defined as the primary particle size.

The organic or inorganic particles in the present invention preferably have a refractive index of 1.70 to 2.80, more preferably 1.75 to 2.80, and 1.80 to 2.80. Most preferred. The refractive index can be suitably achieved by using zirconium oxide particles. The refractive index of the medium refractive index layer can be adjusted to a predetermined refractive index by changing the amount of the particles.
Content of the said organic or inorganic particle (A) is 30-60 mass% with respect to solid content in the said composition, 35-55 mass% is preferable, and 40-50 mass% is still more preferable. When the amount is less than 30% by mass, the number of particles decreases, and the leveling agent cannot be concentrated on the surface of the layer, resulting in deterioration of scratch resistance. When it exceeds 60% by mass, the binder concentration in the layer is lowered, the bonding property with the adjacent layer is lowered, and the scratch resistance is deteriorated.

The specific surface area of the organic or inorganic particles is preferably from 10 to 400 m ² / g, more preferably from 20 to 200 m ² / g, and most preferably from 30 to 150 m ² / g.

  Organic or inorganic particles are used in the dispersion liquid or coating liquid for physical stabilization such as plasma discharge treatment or corona discharge treatment in order to stabilize the dispersion or to increase the affinity and binding properties with the binder component. Surface treatment, chemical surface treatment with a surfactant, a coupling agent, or the like may be performed. The use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Among these, treatment with a silane coupling agent having an acryloyl group or a methacryloyl group is particularly effective. Chemical surface treatment agents for inorganic fine particles, solvents, catalysts, and dispersion stabilizers are described in JP-A-2006-17870, [0058] to [0083].

<(B) Compound having three or more unsaturated double bonds>
In the present invention, the composition forming the intermediate refractive index layer contains a compound having three or more unsaturated double bonds.
A compound having 3 or more unsaturated double bonds can function as a binder. From the viewpoint of curability and improving the strength and scratch resistance of the coating film, the number of unsaturated double bonds is 4 or more. Preferably there is.

Examples of the compound having three or more unsaturated double bonds include compounds having an unsaturated double bond such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group and -C (O) OCH = CH ₂ are preferred. Particularly preferably, a compound containing three or more (meth) acryloyl groups in one molecule described below can be used.

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

  Among these, esters of polyhydric alcohol and (meth) acrylic acid are preferable. For example, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate , Pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO modified trimethylolpropane tri (meth) acrylate, PO modified trimethylolpropane tri (meth) acrylate, EO modified Tri (meth) acrylate phosphate, trimethylolethane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate Rate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-chlorohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate, caprolactone modified tris And (acryloxyethyl) isocyanurate.

Commercially available polyfunctional acrylate compounds having a (meth) acryloyl group can be used, such as KAYARAD DPHA manufactured by Nippon Kayaku Co., Ltd., PET-30, Shin Nakamura Chemical Co., Ltd., NK Ester A -TMMT, A-TMPT, etc. can be mentioned.
Commercially available urethane (meth) acrylates can be used, such as U-4HA manufactured by Shin-Nakamura Chemical Co., Ltd., EB5129 manufactured by Daicel-Cytec Co., Ltd., and the like.
Non-fluorinated polyfunctional monomers are described in paragraphs [0114] to [0122] of JP-A-2009-98658, and the same applies to the present invention.

  In the present invention, from the viewpoint of curability and the viewpoint of improving the strength and scratch resistance of the coating film, the molecular weight of the compound (B) having three or more unsaturated double bonds is divided by the number of functional groups. The molecular weight / functional group number is preferably 100 or less, and more preferably 90 or less. Although there is no restriction | limiting in particular as a lower limit of the molecular weight / functional group number of a compound (B), It is preferable that it is 70 or more.

  In the composition for forming a medium refractive index layer according to the present invention, the content of the compound having three or more unsaturated double bonds gives a sufficient polymerization rate and imparts hardness, etc. 40-70 mass% is preferable with respect to the total solid content in a composition, and 50-60 mass% is more preferable.

<(C) Polymer containing a repeating unit corresponding to the monomer represented by Formula 1>
In the present invention, the composition forming the intermediate refractive index layer contains a polymer containing a repeating unit corresponding to the monomer represented by the general formula 1 (hereinafter, also simply referred to as “fluorine polymer”), The said polymer (C) is 0.2-2.0 mass% with respect to the total solid in the said composition.
The polymer (C) containing a repeating unit corresponding to the monomer represented by the general formula 1 (fluoroaliphatic group-containing monomer) has an effect of preventing film thickness unevenness as a fluorine leveling agent.

The polymer containing a repeating unit corresponding to the monomer represented by the general formula 1 is a polymer of a repeating unit (polymerization unit) corresponding to the monomer (i) below or a monomer (i) below. And an acrylic resin, a methacrylic resin, and a copolymer with a vinyl monomer copolymerizable therewith, including a repeating unit (polymerized unit) and a repeating unit (polymerized unit) corresponding to the monomer (ii) below. It is done. Examples of such monomers include Polymer Handbook 2nd ed. , J .; Brandrup, Wiley Interscience (1975) Chapter 2, Pages 1-483 can be used.
For example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid, methacrylic acid, acrylic esters, methacrylic esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. I can give you.

  (I) Fluoroaliphatic group-containing monomer represented by the following general formula 1

General formula 1

In the general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group, preferably a hydrogen atom or a methyl group. X represents an oxygen atom, a sulfur atom or —N (R ¹² ) —, more preferably an oxygen atom or —N (R ¹² ) —, and still more preferably an oxygen atom. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and still more preferably a hydrogen atom or a methyl group. R _f represents —CF ₃ or —CF ₂ H.
M in the general formula 1 represents an integer of 1 to 6, more preferably 1 to 3, and still more preferably 1.
N in the general formula 1 represents an integer of 1 to 11, more preferably 1 to 9, and still more preferably 1 to 6. R _f is preferably —CF ₂ H.
In addition, two or more kinds of polymer units derived from the fluoroaliphatic group-containing monomer represented by the general formula 1 may be contained in the fluorine-based polymer as a constituent component.

(Ii) Monomer represented by the following general formula 2 copolymerizable with the above (i)

In the general formula 2, R ¹³ represents a hydrogen atom, a halogen atom or a methyl group, a hydrogen atom, more preferably a methyl group. Y represents an oxygen atom, a sulfur atom or —N (R ¹⁵ ) —, more preferably an oxygen atom or —N (R ¹⁵ ) —, and still more preferably an oxygen atom. R ¹⁵ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and still more preferably a hydrogen atom or a methyl group.
R ¹⁴ represents a linear, branched or cyclic alkyl group having 1 to 60 carbon atoms, or an aromatic group (for example, a phenyl group or a naphthyl group). The alkyl group may include a poly (alkyleneoxy) group. Furthermore, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms is more preferable, and a linear or branched alkyl group having 1 to 10 carbon atoms is very preferable.

  The amount of the fluoroaliphatic group-containing monomer represented by the above general formula 1 used for the production of a preferred fluoropolymer is 10% by mass or more, preferably 25% based on the total amount of the monomer of the fluoropolymer. % Or more, and more preferably in the range of 40 to 90% by mass.

Hereinafter, although the specific structural example of a preferable fluorine-type polymer is shown, it is not this limitation.
In addition, the number in a formula shows the molar ratio of each monomer component. Mw represents a mass average molecular weight.

The mass average molecular weight of the polymer containing a repeating unit corresponding to the monomer represented by the general formula 1 is preferably 3000 to 100,000, and more preferably 5,000 to 80,000.
Furthermore, the preferable content of the polymer containing a repeating unit corresponding to the monomer represented by Formula 1 is 0.5 to 1.5% by mass with respect to the total solid content in the composition. Is preferred. If the content of the polymer containing the repeating unit corresponding to the monomer represented by the general formula 1 is too small, the effect of reducing the film thickness unevenness is insufficient, and if it is too large, the coating film is sufficiently dried. It may become unclear and may adversely affect the performance as a coating film (for example, reflectivity and scratch resistance).

(Polymerization initiator)
In the present invention, the composition forming the medium refractive index layer preferably contains a polymerization initiator.
As the polymerization initiator, it is preferable to use a photopolymerization initiator. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable.
Examples of the photo radical polymerization initiator include acetophenones, benzophenones, Michler's benzoylbenzoate, α-amyloxime ester, tetramethylthiuram monosulfide, and thioxanthones.

  As a commercially available radical photopolymerization initiator, Kayacure (DETX-S, BP-100, BDMK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, manufactured by Nippon Kayaku Co., Ltd. MCA, etc.), Irgacure (651, 184, 127, 500, 907, 369, 1173, 2959, 4265, 4263, etc.) manufactured by Ciba Specialty Chemicals Co., Ltd., Esacure (KIP100F, KB1, EB3, manufactured by Sartomer) BP, X33, KT046, KT37, KIP150, TZT) and the like.

In particular, photocleavable photoradical polymerization initiators are preferred. The photocleavable photoradical polymerization initiator is described in the latest UV curing technology (P.159, issuer; Kazuhiro Takasawa, publisher; Technical Information Association, published in 1991).
Examples of commercially available photocleavable photoradical polymerization initiators include Irgacure (651, 184, 127, 907) manufactured by Ciba Specialty Chemicals.

The photopolymerization initiator is preferably used in the range of 0.1 to 15 parts by mass, more preferably in the range of 1 to 10 parts by mass with respect to 100 parts by mass of the compound having three or more unsaturated double bonds. It is.
In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.
Examples of commercially available photosensitizers include KAYACURE (DMBI, EPA) manufactured by Nippon Kayaku Co., Ltd.
The photopolymerization reaction is preferably performed by ultraviolet irradiation after application and drying of the medium refractive index layer.

(solvent)
As the solvent, it is preferable to use a liquid having a boiling point of 60 to 170 ° C. Specifically, water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ester (eg, methyl acetate, ethyl acetate, propyl acetate) , Butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene chloride, chloroform, carbon tetrachloride), aromatic hydrocarbons (Eg, benzene, toluene, xylene), amide (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ether (eg, diethyl ether, dioxane, tetrahydrofuran), ether alcohol (eg, 1-methoxy) 2-propanol) and the like. Of these, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are preferred, and particularly preferred dispersion media are methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone.
The amount of the solvent used is preferably such that the solid content concentration of the coating composition is 1 to 20% by mass, more preferably 2 to 15% by mass with respect to the medium refractive index layer. preferable.

Hereinafter, the antireflection film of the present invention will be described.
(Layer structure of antireflection film)
The antireflection film of the present invention is a medium refractive index layer / high refractive index layer / low refractive index layer in this order on a transparent support having a hard coat layer from the viewpoint of durability, optical properties, cost, productivity, and the like. Have. For example, configurations described in JP-A-8-122504, JP-A-8-110401, JP-A-10-300902, JP-A-2002-243906, JP-A-2000-11706, and the like can be given. Other functions may be imparted to each layer, for example, an antifouling low refractive index layer or an antistatic high refractive index layer (eg, JP-A-10-206603, JP-A-2002). -243906 publication etc.) etc. are mentioned.
The layer structure of the antireflection film of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing an antireflection film of the present invention.
The antireflection film shown in FIG. 1 is a three-layer thin film interference type antireflection film having excellent antireflection performance, and includes a transparent support 1 and a low refractive index layer 5 located on one surface of the transparent support 1. Between the low refractive index layer 5 and the transparent support 1, a high refractive index layer 4 having a higher refractive index than the low refractive index layer is provided as a thin film layer. Further, a thin film layer (hereinafter simply referred to as “thin film layer” refers to these low refractive index layer, high refractive index layer and medium refractive index layer) between the high refractive index layer 4 and the transparent support 1. A medium refractive index layer 3 is provided. A hard coat layer 2 is provided between the intermediate refractive index layer 3 and the transparent support 1.
In the present invention, the transparent support 1, the middle refractive index layer 3, the high refractive index layer 4, and the low refractive index layer 5 preferably have a refractive index that satisfies the following relationship.

  The refractive index of the high refractive index layer> the refractive index of the medium refractive index layer> the refractive index of the transparent support> the refractive index of the low refractive index layer.

In the antireflection film of the present invention, a medium refractive index layer, a high refractive index layer, and a low refractive index layer are laminated in this order from the transparent support side on the transparent support,
The refractive index of the middle refractive index layer at a wavelength of 550 nm is 1.57 to 1.62, and the thickness of the middle refractive index layer is 55.0 nm to 75.0 nm.
The refractive index of the high refractive index layer at a wavelength of 550 nm is 1.70 to 1.74, and the thickness of the high refractive index layer is 125.0 nm to 145.0 nm.
The refractive index of the low refractive index layer at a wavelength of 550 nm is preferably 1.33 to 1.38, and the thickness of the low refractive index layer is preferably 90.0 nm to 100.0 nm.

The antireflection film of the present invention preferably has the following configuration among the above configurations.
Constitution:
The refractive index at a wavelength of 550 nm of the middle refractive index layer is 1.59 to 1.60, and the thickness of the middle refractive index layer is 60.0 nm to 70.0 nm.
The refractive index at a wavelength of 550 nm of the high refractive index layer is 1.70 to 1.74, and the thickness of the high refractive index layer is 130.0 nm to 140.0 nm,
An antireflection film which is a low refractive index layer having a refractive index of 1.33 to 1.38 at a wavelength of 550 nm of the low refractive index layer and a thickness of the low refractive index layer of 90.0 nm to 100.0 nm.

  By setting the refractive index and thickness of each layer within the above range, the variation in reflected color when the viewing angle is changed can be further reduced.

The refractive index of each layer can be measured with a multi-wavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.) by applying the coating solution of each layer to a glass plate so as to have a thickness of 3 to 5 μm. . In this specification, the refractive index measured using the filter of “DR-M2, M4 interference filter 546 (e) nm part number: RE-3523” can be adopted as the refractive index at a wavelength of 550 nm.
The film thickness of each layer can be measured by cross-sectional observation using a reflection spectral film thickness meter “FE-3000” (manufactured by Otsuka Electronics Co., Ltd.) utilizing light interference or a TEM (transmission electron microscope). Although the reflection spectral film thickness meter can also measure the refractive index simultaneously with the film thickness, it is desirable to use the refractive index of each layer measured by another means in order to increase the measurement accuracy of the film thickness. When the refractive index of each layer cannot be measured, the film thickness measurement by TEM is desirable. In that case, it is desirable to measure 10 or more locations and use an average value.

Next, the transparent support and each layer constituting the antireflection film of the present invention will be described in detail.
[Transparent support]
As the transparent support of the antireflection film of the present invention, a transparent substrate film is preferable. There is no limitation in particular as a transparent base film, such as a transparent resin film, a transparent resin board, a transparent resin sheet, and transparent glass. Transparent resin films include cellulose acylate films (for example, cellulose triacetate film (refractive index 1.48), cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film), polyethylene terephthalate film, polyethersulfone. Film, polyacrylic resin film, polyurethane resin film, polyester film, polycarbonate film, polysulfone film, polyether film, polymethylpentene film, polyetherketone film, (meth) acrylonitrile film polyolefin, alicyclic structure Polymer (Norbornene resin (Arton: trade name, manufactured by JSR Corporation, amorphous polyolefin (ZEONEX: Name, Nippon Zeon Co., Ltd.)), and the like. Among the cellulose acylate film, a polyethylene terephthalate, preferably a polymer having an alicyclic structure, particularly preferred is a cellulose acylate film.
Although the thickness of a transparent support body can use the thing about 25 micrometers-1000 micrometers normally, Preferably it is 25 micrometers-250 micrometers, and it is more preferable that it is 30 micrometers-90 micrometers.
Although the arbitrary width | variety of a transparent support body can be used, the thing of 100-5000 mm is normally used from the point of handling, a yield, and productivity, and it is preferable that it is 800-3000 mm, 1000-2000 mm More preferably it is. The transparent support can be handled in the form of a roll, and is usually 100 m to 5000 m, preferably 500 m to 3000 m.
The surface of the transparent support is preferably smooth, and the average roughness Ra is preferably 1 μm or less, preferably 0.0001 to 0.5 μm, and 0.001 to 0.1 μm. More preferably.
The transparent support is described in paragraphs [0163] to [0169] of JP-A-2009-98658, and the same applies to the present invention.

[Hard coat layer]
The hard coat layer in the antireflection film of the present invention can impart the physical strength of the film. As a result, the scratch-resistant surface such as a pencil scratch test can be strengthened.
In the present invention, an intermediate refractive index layer and a high refractive index layer are provided between the hard coat layer and the low refractive index layer to constitute an antireflection film.
The hard coat layer may be composed of two or more layers.

  The refractive index of the hard coat layer in the present invention is preferably in the range of 1.48 to 2.00, more preferably 1.48 to 1, from the optical design for obtaining an antireflection film. .60. In the present invention, since there is at least one low refractive index layer on the hard coat layer, if the refractive index is too small, the antireflection property is lowered, and if it is too large, the color of the reflected light tends to be strong. is there.

The film thickness of the hard coat layer is usually about 0.5 μm to 50 μm, preferably 1 μm to 20 μm, more preferably 5 μm to 20 μm, from the viewpoint of imparting sufficient durability and impact resistance to the film.
The strength of the hard coat layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in the pencil hardness test. Furthermore, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.

The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. For example, it is formed by applying a polymerizable composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer on a transparent support and subjecting the polyfunctional monomer or polyfunctional oligomer to a crosslinking reaction or a polymerization reaction. Can do.
The functional group of the ionizing radiation curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.
Examples of the photopolymerizable functional group include unsaturated double bonds such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable. Specifically, the compounds mentioned for the polyfunctional monomer having an unsaturated double bond described below can be preferably used.

(Compound having an unsaturated double bond)
The composition for hard coat layers according to the present invention may contain a compound having an unsaturated double bond.
The compound having an unsaturated double bond can function as a binder, and is preferably a polyfunctional monomer having two or more polymerizable unsaturated groups. The polyfunctional monomer having two or more polymerizable unsaturated groups can function as a curing agent, and can improve the strength and scratch resistance of the coating film. The number of polymerizable unsaturated groups is more preferably 3 or more.

Examples of the compound having an unsaturated double bond include compounds having a polymerizable functional group such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group and —C (O ) OCH = CH ₂ is preferred. Particularly preferably, a compound containing three or more (meth) acryloyl groups in one molecule described below can be used.

  As specific examples and preferred examples of the compound having a polymerizable unsaturated bond, the compound (B) having three or more unsaturated double bonds contained in the composition forming the middle refractive index layer in the present invention is described above. Specific examples and preferred examples are the same.

  The content of the compound having an unsaturated double bond in the composition for forming a hard coat layer according to the present invention provides a sufficient polymerization rate and imparts hardness and the like. 40-98 mass% is preferable with respect to solid content, and 60-95 mass% is more preferable.

[Photopolymerization initiator]
The composition for hard coat layers according to the present invention can contain a photopolymerization initiator.
As photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, Examples include fluoroamine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, and coumarins. Specific examples, preferred embodiments, commercially available products, and the like of the photopolymerization initiator are described in paragraphs [0133] to [0151] of JP-A-2009-098658, and can be suitably used in the present invention as well. it can.

  “Latest UV Curing Technology” {Technical Information Association, Inc.} (1991), p. 159, and “UV Curing System” written by Kiyomi Kato (published by the General Technology Center in 1989), p. Various examples are also described in 65-148 and are useful in the present invention.

  The content of the photopolymerization initiator in the hard coat layer composition according to the present invention is sufficiently large to polymerize the polymerizable compound contained in the hard coat layer composition, and the starting point does not increase too much. From the reason of setting to a sufficiently small amount, 0.5 to 8% by mass is preferable and 1 to 5% by mass is more preferable with respect to the total solid content in the composition for hard coat layer.

(solvent)
The composition for forming a hard coat layer may contain various organic solvents.
In this invention, it is preferable that the hydrophilic solvent is included. Examples of the hydrophilic solvent include alcohol solvents, carbonate solvents, ester solvents and the like, for example, methanol, ethanol, isopropanol, n-butyl alcohol, cyclohexyl alcohol, 2-ethyl-1-hexanol, 2-methyl-1 Hexanol, 2-methoxyethanol, 2-propoxyethanol, 2-butoxyethanol, diacetone alcohol, dimethyl carbonate, diethyl carbonate, diisopropyl carbonate, methyl ethyl carbonate, methyl n-propyl carbonate, ethyl formate, propyl formate, pentyl formate , Methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, ethyl 2-ethoxypropionate, methyl acetoacetate, ethyl acetoacetate, 2-methoxy Methyl acetate, 2-ethoxyethyl acetate, 2-ethoxyethyl acetate, acetone, 1,2-diacetoxy acetone, acetylacetone and the like, may be used in combination of at least one kind alone or two kinds.

  Further, a solvent other than the above may be used. For example, ether solvents, ketone solvents, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents and the like can be mentioned. For example, dibutyl ether, dimethoxyethane, diethoxyethane, propylene oxide, 1,4-dioxane, 1,3-dioxolane, 1,3,5-trioxane, tetrahydrofuran, anisole, phenetole, methyl ethyl ketone (MEK), diethyl ketone, dipropyl Ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, methyl isobutyl ketone, 2-octanone, 2-pentanone, 2-hexanone, ethylene glycol ethyl ether, ethylene glycol isopropyl ether, ethylene glycol butyl ether, propylene glycol methyl ether, ethyl Carbitol, butyl carbitol, hexane, heptane, octane, cyclohexane, methylcyclohexane, ethyl Cyclohexane, benzene, toluene, xylene and the like, can be used singly or in combination of two or more.

  It is preferable to use a solvent such that the solid content in the composition for hard coat layer according to the present invention is in the range of 20 to 80% by mass, more preferably 30 to 75% by mass, and most preferably 40. -70 mass%.

(Surfactant)
It is also suitable to use various surfactants for the composition for hard coat layers according to the present invention. In general, a surfactant can suppress film thickness unevenness caused by variation in drying due to local distribution of drying air.

  Specifically, the surfactant is preferably a fluorine-based surfactant or a silicone-based surfactant. Further, the surfactant is preferably an oligomer or a polymer rather than a low molecular compound.

  When a surfactant is added, the surfactant quickly moves to the surface of the applied liquid film and becomes unevenly distributed, and the surfactant is unevenly distributed on the surface even after the film is dried. The surface energy of the hard coat layer is lowered by the surfactant. From the viewpoint of preventing unevenness of film thickness, repellency, and unevenness of the hard coat layer, the surface energy of the film is preferably low.

Examples of preferred silicone compounds include “X-22-174DX”, “X-22-2426”, “X22-164C”, “X-22-176D” (manufactured by Shin-Etsu Chemical Co., Ltd.) Name); "FM-7725", "FM-5521", "FM-6621" (named above) manufactured by Chisso Corporation; "DMS-U22", "RMS-033" (named above) manufactured by Gelest Product name); “SH200”, “DC11PA”, “ST80PA”, “L7604”, “FZ-2105”, “L-7604”, “Y-7006”, “SS-” manufactured by Toray Dow Corning Co., Ltd. 2801 "(trade name);" TSF400 "(trade name) manufactured by Momentive Performance Materials Japan, but not limited thereto.
The surfactant is preferably contained in the total solid content of the coating composition for the hard coat layer in an amount of 0.01 to 0.5% by mass, and more preferably 0.01 to 0.3% by mass.

  The hard coat layer contains matte particles having an average particle diameter of 1.0 to 10.0 μm, preferably 1.5 to 7.0 μm, such as inorganic compound particles or resin particles, for the purpose of imparting internal scattering properties. May be.

  For the purpose of controlling the refractive index of the hard coat layer, various refractive index monomers or inorganic particles, or both can be added to the binder of the hard coat layer. In addition to the effect of controlling the refractive index, the inorganic particles also have the effect of suppressing cure shrinkage due to the crosslinking reaction. In the present invention, a polymer formed by polymerizing the polyfunctional monomer and / or the high refractive index monomer after the formation of the hard coat layer, and the inorganic particles dispersed therein are referred to as a binder. As inorganic fine particles for controlling the refractive index, silica fine particles are preferably used from the viewpoint of suppressing color unevenness due to interference between the support and the hard coat layer.

(Conductive compound)
The hard coat layer in the present invention may contain a conductive compound for the purpose of imparting antistatic properties. The conductive compound used in the present invention is not particularly limited, and examples thereof include an ion conductive compound and an electron conductive compound. Examples of the ion conductive compound include cationic, anionic, nonionic, and amphoteric ion conductive compounds. Examples of the electron conductive compound include an electron conductive compound which is a non-conjugated polymer or a conjugated polymer in which aromatic carbocycles or aromatic heterocycles are connected by a single bond or a divalent or higher linking group. Among these, a compound having a quaternary ammonium base (cationic compound) is suitable from the viewpoint of high antistatic performance, relatively low cost, and uneven distribution in the substrate side region.

  As the compound having a quaternary ammonium base, either a low molecular type or a high molecular type can be used, but a high molecular cationic antistatic agent is more preferable because there is no variation in antistatic properties due to bleedout or the like. Used. As the cationic compound having a polymer type quaternary ammonium base, it can be appropriately selected from known compounds, and the compounds described in JP2010-084425A, JP46000605A and the like are preferably used. it can.

[Medium refractive index layer]
In the present invention, the refractive index of the middle refractive index layer is adjusted to be a value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. The refractive index of the medium refractive index layer is preferably 1.57 to 1.62, and more preferably 1.58 to 1.60.
The medium refractive index layer can be formed by a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method, particularly a vacuum vapor deposition method or a sputtering method, which is a kind of physical vapor deposition method. An all wet coating method is preferred.

[High refractive index layer]
The refractive index of the high refractive index layer in the present invention is preferably 1.70 to 1.74, more preferably 1.71 to 1.73. The method for forming the high refractive index layer is the same as that described above as the method for forming the medium refractive index layer.

  The high refractive index layer is coated with a coating composition containing inorganic fine particles, a curable resin having a tri- or higher functional polymerizable group (hereinafter sometimes referred to as “binder”), a solvent and a polymerization initiator, It is preferable that the solvent is dried and then cured by heating, irradiation with ionizing radiation, or a combination of both means. When a curable resin or an initiator is used, a high refractive index layer having excellent scratch resistance and adhesion can be formed by curing the curable resin by a polymerization reaction by heat and / or ionizing radiation after coating.

(Inorganic fine particles)
As the inorganic fine particles, metal (eg, Ti, Zr, In, Zn, Sn, Sb, Al) oxides are preferred, and zirconium oxide fine particles are most preferred from the viewpoint of refractive index. However, from the viewpoint of conductivity, it is preferable to use inorganic fine particles whose main component is an oxide of at least one kind of metal of Sb, In, and Sn. The refractive index can be adjusted to a predetermined refractive index by changing the amount of the inorganic fine particles. The average particle diameter of the inorganic fine particles in the layer is preferably 1 to 120 nm, more preferably 1 to 60 nm, and further preferably 2 to 40 nm when zirconium oxide is used as a main component. Within this range, haze is suppressed, dispersion stability, and adhesion with the upper layer due to moderate irregularities on the surface become favorable, which is preferable.

The inorganic fine particles mainly composed of zirconium oxide in the present invention preferably have a refractive index of 1.90 to 2.80, more preferably 2.10 to 2.80, and 2.20 to 2.80. 80 is most preferred.
The addition amount of the inorganic fine particles is 40 to 90% by mass, preferably 50 to 85% by mass, and more preferably 60 to 80% by mass with respect to the solid content of the entire high refractive index layer.

The particle diameter of the inorganic fine particles can be measured by a light scattering method or an electron micrograph.
The specific surface area of the inorganic fine particles is preferably 10 to 400 m ² / g, more preferably from 20 to 200 m ² / g, and most preferably from 30 to 150 m ² / g.

  Inorganic fine particles are treated with physical surface treatment such as plasma discharge treatment or corona discharge treatment in order to stabilize dispersion in the dispersion or coating solution, or to improve the affinity and binding properties with the binder component. Chemical surface treatment with a surfactant, a coupling agent, or the like may be performed. The use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Among these, treatment with a silane coupling agent having an acryloyl group or a methacryloyl group is particularly effective. Chemical surface treatment agents for inorganic fine particles, solvents, catalysts, and dispersion stabilizers are described in JP-A-2006-17870, [0058] to [0083].

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

As a specific example of a photopolymerizable polyfunctional monomer having a photopolymerizable functional group,
(Meth) acrylic acid diesters of alkylene glycol such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, propylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyoxyalkylene glycols such as triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 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- (acryloxy · diethoxy) phenyl} propane and 2-bis {4- (acryloxy · polypropoxy) phenyl} propane Etc.

  Furthermore, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates are also preferably used as the photopolymerizable polyfunctional monomer.

Among these, esters of polyhydric alcohol and (meth) acrylic acid are preferable. More preferably, a polyfunctional monomer having 3 or more (meth) acryloyl groups in one molecule is preferable. Specifically, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, 1,2,4-cyclohexanetetra (meth) acrylate, pentaglycerol triacrylate, pentaerythritol tetra (meth) acrylate, penta Erythritol tri (meth) acrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol triacrylate, tripentaerythritol hexatriacrylate, etc. Is mentioned. Two or more polyfunctional monomers may be used in combination.
The usage-amount of curable resin can be adjusted in the range with which the refractive index of each above-mentioned layer is satisfy | filled.

(Polymerization initiator)
As a polymerization initiator, the thing similar to what was mentioned above as a specific example of a polymerization initiator about a middle refractive index layer coating composition, and a preferable example is mentioned.

It is preferable to use a photoinitiator in the range of 0.1-15 mass parts with respect to 100 mass parts of curable resin, More preferably, it is the range of 1-10 mass parts.
In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.
Examples of commercially available photosensitizers include KAYACURE (DMBI, EPA) manufactured by Nippon Kayaku Co., Ltd.
The photopolymerization reaction is preferably performed by ultraviolet irradiation after the high refractive index layer is applied and dried.

  In addition to the above-mentioned components (inorganic fine particles, curable resins, polymerization initiators, photosensitizers, etc.), the high refractive index layer includes a surfactant, an antistatic agent, a coupling agent, a thickener, and an anti-coloring agent. , Colorants (pigments, dyes), antifoaming agents, leveling agents, flame retardants, UV absorbers, infrared absorbers, adhesion promoters, polymerization inhibitors, antioxidants, surface modifiers, conductive metal particles, Etc. can also be added.

(solvent)
As said solvent, the thing similar to what was mentioned above as a specific example of a solvent about a medium refractive index layer coating composition, and a preferable example is mentioned.
The amount of the solvent used is preferably such that the solid content concentration of the high refractive index layer coating composition is 2 to 30% by mass, and more preferably 3 to 20% by mass.

  The high refractive index layer and the medium refractive index layer used in the present invention are a curable resin (for example, the above-mentioned ionizing radiation curing described above) that is a binder precursor necessary for matrix formation in a dispersion liquid in which inorganic fine particles are dispersed in a dispersion medium. Functional polyfunctional monomers and polyfunctional oligomers), photopolymerization initiators, etc. to form a coating composition for forming a high refractive index layer and a medium refractive index layer, and a high refractive index layer and a medium refractive index on a transparent support. It is preferably formed by applying a coating composition for forming a layer and curing it by a crosslinking reaction or a polymerization reaction of a curable resin.

Furthermore, it is preferable to cause the binder of the high refractive index layer and the medium refractive index layer to undergo a crosslinking reaction or a polymerization reaction with the dispersant simultaneously with or after the coating of the layer.
The binder of the high refractive index layer and the medium refractive index layer produced in this way is, for example, the above-mentioned preferred dispersant and ionizing radiation curable polyfunctional monomer or polyfunctional oligomer are crosslinked or polymerized to form a binder. The anionic group of the dispersant is incorporated. Furthermore, the binder of the high refractive index layer and the medium refractive index layer has a function in which the anionic group maintains the dispersion state of the inorganic fine particles, and the crosslinked or polymerized structure imparts a film forming ability to the binder and contains the inorganic fine particles. To improve the physical strength, chemical resistance and weather resistance of the high refractive index layer and medium refractive index layer.

In the formation of the high refractive index layer and the middle refractive index layer, the crosslinking reaction or polymerization reaction of the curable resin is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less.
By forming the high refractive index layer and the medium refractive index layer in an atmosphere having an oxygen concentration of 10% by volume or less, the physical strength, chemical resistance, and weather resistance of the high refractive index layer, as well as the high refractive index layer and the medium refractive index, The adhesion between the refractive index layer, the high refractive index layer, and the medium refractive index layer and the adjacent layer can be improved.
Preferably, it is formed by a crosslinking reaction or a polymerization reaction of a curable resin in an atmosphere having an oxygen concentration of 6% by volume or less, more preferably an oxygen concentration of 4% by volume or less, particularly preferably an oxygen concentration of 2% by volume. Hereinafter, it is most preferably 1% by volume or less.

[Low refractive index layer]
The low refractive index layer suitably used in the present invention preferably has a refractive index of 1.33 to 1.38, more preferably 1.34 to 1.37. Within the above range, the reflectance can be suppressed and the film strength can be maintained, which is preferable. The low refractive index layer can be formed by a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method, particularly a vacuum vapor deposition method or a sputtering method, which is a kind of physical vapor deposition method. It is preferable to use an all wet coating method using a low refractive index layer forming solution coating composition to be described later. The low refractive index layer preferably contains inorganic fine particles. At least one of the inorganic fine particles is preferably a hollow particle, and hollow particles mainly composed of silica (hereinafter referred to as hollow silica particles) are used. Particularly preferred.
The thickness of the low refractive index layer is preferably 90.0 to 100.0 nm, and more preferably 95.0 to 100.0 nm.
The haze of the low refractive index layer is preferably 3% or less, more preferably 2% or less, and most preferably 1% or less.
The strength of the antireflection film formed up to the low refractive index layer is preferably H or more, more preferably 2H or more, and most preferably 3H or more in a pencil hardness test under a 500 g load.
In order to improve the antifouling performance of the antireflection film, it is preferable that the contact angle of the surface with respect to water is 90 ° or more. More preferably, it is 95 ° or more, and particularly preferably 100 ° or more.

(Inorganic fine particles)
The inorganic fine particles that can be used in the low refractive index layer are preferably hollow particles.
The hollow particles preferably have a refractive index of 1.17 to 1.40, more preferably 1.17 to 1.35, and most preferably 1.17 to 1.33. As the hollow particles, hollow silica particles are preferable, and the hollow silica particles will be described below as an example. The refractive index here represents the refractive index of the whole particle, and does not represent the refractive index of only the outer shell silica forming the hollow silica particles. At this time, assuming that the radius of the pores in the particle is a and the radius of the particle outer shell is b, the porosity x represented by the following formula (7) is preferably 10 to 60%, more preferably 20 to 60. %, Most preferably 30-60%.
Equation (7): x = (4πa 3/3) / (4πb 3/3) × 100
If hollow silica particles are made to have a lower refractive index and a higher porosity, the thickness of the outer shell becomes thinner and the strength of the particles becomes weaker. Particles are preferred.
The refractive index of these hollow silica particles can be measured with an Abbe refractometer (manufactured by Atago Co., Ltd.).
A method for producing hollow silica particles is described in, for example, Japanese Patent Application Laid-Open Nos. 2001-233611 and 2002-79616.
A commercial item can also be used as a hollow silica particle.

The coating amount of the hollow silica particles is ^preferably from ^{1mg / m 2 ~100mg / m 2} , more preferably ^{5mg / m 2 ~80mg / m 2} , more preferably from ^{10mg / m 2 ~60mg / m 2} . Within this range, the effects of lowering the refractive index and improving the scratch resistance are good, prevent the formation of fine irregularities on the surface of the low refractive index layer, and maintain the appearance and integrated reflectivity such as black tightening. can do.
The average particle diameter of the hollow silica particles is preferably 30% or more and 150% or less of the thickness of the low refractive index layer, more preferably 35% or more and 80% or less, and further preferably 40% or more and 60% or less.
That is, when the thickness of the low refractive index layer is 100 nm, the particle size of the hollow silica particles is preferably 30 nm or more and 150 nm or less, more preferably 35 nm or more and 80 nm or less, and still more preferably 40 nm or more and 60 nm or less.
By setting the particle size within the above range, the ratio of the pores is kept sufficiently, the refractive index is sufficiently lowered, the surface of the low refractive index layer is prevented from forming fine irregularities, the appearance of black tightening, integration The reflectance can be maintained well. The silica fine particles may be either crystalline or amorphous, and monodisperse particles are preferred. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.
Here, the average particle diameter of the hollow silica particles can be determined from an electron micrograph.

In the present invention, silica particles having no pores can be used in combination with hollow silica particles. The preferable particle size of silica without voids is 5 nm to 150 nm, more preferably 10 nm to 80 nm, and most preferably 15 nm to 60 nm.
In addition, at least one kind of silica fine particles having an average particle size of less than 25% of the thickness of the low refractive index layer (referred to as “silica fine particles with small size particle size”) is used as silica fine particles with the above particle size (“large size particles”). It is preferably used in combination with “silica fine particles having a diameter”.
Since the fine silica particles having a small size can be present in the gaps between the fine silica particles having a large size, the fine particles can contribute as a retaining agent for the fine silica particles having a large size.
The average particle diameter of the silica fine particles having a small size is preferably 1 nm to 20 nm, more preferably 5 nm to 15 nm, and particularly preferably 10 nm to 15 nm. Use of such silica fine particles is preferable in terms of raw material costs and a retaining agent effect.

  Hollow particles are treated with physical surface treatment such as plasma discharge treatment or corona discharge treatment in order to stabilize dispersion in the dispersion or coating solution, or to improve the affinity and binding properties with the binder component. Chemical surface treatment with a surfactant, a coupling agent, or the like may be performed. The use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Among these, treatment with a silane coupling agent having an acryloyl group or a methacryloyl group is particularly effective. Hollow particle chemical surface treatment agents, solvents, catalysts, and dispersion stabilizers are described in JP-A-2006-17870, [0058] to [0083].

The low refractive index layer is formed by applying a coating composition containing a film-forming solute and one or more solvents, drying the solvent, and then curing by heating, irradiation with ionizing radiation, or a combination of both means. It is preferred that
The solute is preferably either a composition containing a heat- or ionizing radiation-curable fluorine-containing curable resin, or a hydrolyzate of an organic silyl compound and a partial condensate thereof.
It is more preferable to use a composition containing a fluorine-containing curable resin, and a mode in which a hydrolyzate of an organic silyl compound and a partial condensate thereof are used supplementarily is more preferable. The addition amount of the hydrolyzate of the organic silyl compound and the partial condensate thereof used in an auxiliary amount is 10 to 40% by mass of the fluorinated curable resin.

(Fluorine-containing curable resin)
Examples of the fluorine-containing curable resin (hereinafter also referred to as “fluorinated polymer”) include perfluoroalkyl group-containing silane compounds (for example, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane). In addition to hydrolysis and dehydration condensates, there may be mentioned fluorine-containing copolymers having a fluorine-containing monomer unit and a constituent unit for imparting crosslinking reactivity as constituent components. In particular, the low refractive index layer of the present invention is formed by a cured film of a copolymer comprising a repeating unit derived from a fluorine-containing vinyl monomer and a repeating unit having a (meth) acryloyl group in the side chain as essential constituent components. Is preferred. It is also preferable to use a curing agent such as polyfunctional (meth) acrylate in combination from the viewpoint of achieving both low refractive index and film hardness. Although there is no restriction | limiting in particular in the mixing ratio of this fluoropolymer and this polyfunctional (meth) acrylate, It is desirable to set it as the mixing ratio which does not raise | generate phase separation with the film after drying. Of course, only one of them can be used. Specific examples of the polyfunctional (meth) acrylate include a photopolymerizable polyfunctional monomer described in the high refractive index layer.

Examples of preferred fluorine-containing curable resins used for the low refractive index layer of the present invention will be described below.
Examples of the fluorine-containing vinyl monomer include fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, etc.), (meth) acrylic acid moieties or fully fluorinated alkyl ester derivatives (for example, biscoat 6FM (trade name) , Osaka Organic Chemical Co., Ltd.), M-2020 (trade name, manufactured by Daikin Co., Ltd.), fully or partially fluorinated vinyl ethers, and the like. Preferred are perfluoroolefins, refractive index, solubility, and transparency. From the viewpoint of availability, hexafluoropropylene is particularly preferable. In the present invention, the fluorine-containing vinyl monomer is preferably introduced so that the fluorine content of the copolymer is 20 to 60% by mass, more preferably 25 to 55% by mass, and particularly preferably 30 to 50%. This is a case of mass%. By setting the composition ratio of the fluorine-containing vinyl monomer within the above range, the refractive index can be sufficiently lowered and the film strength can be maintained.

  The fluorine-containing curable resin used for the low refractive index layer preferably has a crosslinking reactive group. As structural units for imparting crosslinking reactivity, structural units obtained by polymerization of monomers having a self-crosslinkable functional group in the molecule in advance such as glycidyl (meth) acrylate and glycidyl vinyl ether, carboxy group, hydroxy group, amino group Obtained by polymerization of a monomer having a sulfo group or the like (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, maleic acid, crotonic acid, etc.) And a structural unit obtained by introducing a crosslinking reactive group such as a (meth) acryloyl group into these structural units by a polymer reaction (for example, it can be introduced by a technique such as allowing acrylic acid chloride to act on a hydroxy group) But It is below. The copolymer as the fluorine-containing polymer used in the low refractive index layer preferably has a repeating unit having a (meth) acryloyl group in the side chain as an essential constituent component. Generally, the (meth) acryloyl group-containing repeating unit preferably accounts for 5 to 90% by mass, more preferably 30 to 70% by mass, although it varies depending on the type of repeating unit derived from the fluorine-containing vinyl monomer. It is particularly preferred to account for ~ 60% by weight. Increasing the composition ratio of these (meth) acryloyl group-containing repeating units improves the film strength but also increases the refractive index, which is preferable.

  In the copolymer useful for the present invention, in addition to the repeating unit derived from the above-mentioned fluorine-containing vinyl monomer and the repeating unit having a (meth) acryloyl group in the side chain, the adhesiveness to the transparent support, the Tg of the polymer (on the film hardness) In addition, other vinyl monomers can be appropriately copolymerized from various viewpoints such as solubility in solvents, transparency, slipperiness, dust resistance and antifouling properties. A plurality of these vinyl monomers may be combined depending on the purpose, and are preferably introduced in the range of 0 to 65 mol% in the copolymer in total, and more preferably in the range of 0 to 40 mol%. The range of 0 to 30 mol% is particularly preferable.

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

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

  As a preferred form of the fluorine-containing curable resin used in the present invention, the following general formula III may be mentioned.

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

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

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

  Examples of preferred vinyl monomers include methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, vinyl ethers such as allyl vinyl ether, vinyl acetate, propionic acid Vinyl esters such as vinyl and vinyl butyrate, methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, allyl (meth) acrylate, (meth) acryloyloxypropyltrimethoxysilane, etc. (Meth) acrylates, styrene, styrene derivatives such as p-hydroxymethylstyrene, crotonic acid, male Acid, can be mentioned and unsaturated carboxylic acids and derivatives thereof such as itaconic acid, more preferably a vinyl ether derivative, vinyl ester derivatives, particularly preferably a vinyl ether derivative.

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

  As a particularly preferred form of the copolymer used in the present invention, general formula IV can be mentioned.

In the general formula IV, X, x, and y have the same meanings as X, x, and y in the general formula III, and preferred ranges are also the same.
n represents an integer of 2 ≦ n ≦ 10, preferably 2 ≦ n ≦ 6, and particularly preferably 2 ≦ n ≦ 4.
B represents a repeating unit derived from an arbitrary vinyl monomer, and may be composed of a single composition or a plurality of compositions. As an example, what was demonstrated as an example of A in the said general formula III is applicable.
z1 and z2 represent mol% of each repeating unit, and represent values satisfying 0 ≦ z1 ≦ 65 and 0 ≦ z2 ≦ 65. However, x + y + z1 + z2 = 100. It is preferable that 0 ≦ z1 ≦ 30 and 0 ≦ z2 ≦ 10 respectively, and it is particularly preferable that 0 ≦ z1 ≦ 10 and 0 ≦ z2 ≦ 5.

  For the copolymer represented by the general formula III or IV, for example, a (meth) acryloyl group is introduced into a copolymer comprising a hexafluoropropylene component and a hydroxyalkyl vinyl ether component by any one of the methods described above. Can be synthesized.

  Although the preferable example of the copolymer useful by this invention is shown below, this invention is not limited to these.

  The synthesis of the copolymer as the fluorine-containing curable resin used in the present invention can be carried out by using various polymerization methods such as solution polymerization, precipitation polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization. After the synthesis, it can be carried out by introducing a (meth) acryloyl group by the polymer reaction. The polymerization reaction can be performed by a known operation such as a batch system, a semi-continuous system, or a continuous system.

  The polymerization initiation method includes a method using a radical initiator, a method of irradiating light or radiation, and the like. These polymerization methods and polymerization initiation methods are, for example, the revised version of Tsuruta Junji “Polymer Synthesis Method” (published by Nikkan Kogyo Shimbun, 1971), Takatsu Otsu, Masato Kinoshita, “Experimental Methods for Polymer Synthesis” It is described in pp. 47-154 published in 1972.

  Among the above polymerization methods, a solution polymerization method using a radical initiator is particularly preferable. Solvents used in the solution polymerization method include, for example, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran, dioxane, N, N-dimethylformamide, N, N-dimethylacetamide, benzene, toluene, acetonitrile, A single organic solvent such as methylene chloride, chloroform, dichloroethane, methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol, or a mixture of two or more thereof may be used, or a mixed solvent with water may be used.

  The polymerization temperature needs to be set in relation to the molecular weight of the polymer to be produced, the type of initiator, and the like, and can be from 0 ° C. or lower to 100 ° C. or higher, but it is preferable to perform the polymerization in the range of 50 to 100 ° C.

The reaction pressure can be selected as appropriate, but is usually 0.098 to 9.8 MPa (1 to 100 kg / cm ² ), and particularly preferably about 0.098 to 2.94 MPa (1 to 30 kg / cm ² ). . The reaction time is about 5 to 30 hours.

As the reprecipitation solvent for the obtained polymer, isopropanol, hexane, methanol and the like are preferable.
A commercial item can also be used as a fluorine-containing curable resin.
The amount of the fluorine-containing curable resin thus obtained is preferably 10 to 98% by mass, more preferably 30 to 95% by mass in the total solid content of the low refractive index layer coating composition. . In particular, when inorganic fine particles are used in combination, it is preferably 30 to 80% by mass, and more preferably 40 to 75% by mass.

(Coating composition for forming a low refractive index layer)
The coating composition for forming a low refractive index layer usually takes the form of a liquid, and preferably contains the inorganic fine particles and the fluorine-containing curable resin, and if necessary, various additives and radical polymerization initiators in an appropriate solvent. It is prepared by dissolving in At this time, the concentration of the solid content is appropriately selected depending on the use, but is generally about 0.01 to 60% by mass, preferably 0.5 to 50% by mass, particularly preferably 1 to 20% by mass. Degree.

  The radical polymerization initiator may be in any form of generating radicals by the action of heat or generating radicals by the action of light.

As the compound that initiates radical polymerization by the action of heat, organic or inorganic peroxides, organic azo, diazo compounds, and the like can be used.
Specifically, benzoyl peroxide, halogen benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide as organic peroxides, hydrogen peroxide, peroxides as inorganic peroxides. Ammonium sulfate, potassium persulfate, etc., 2-azo-bis-isobutyronitrile, 2-azo-bis-propionitrile, 2-azo-bis-cyclohexanedinitrile, etc. as diazo compounds, diazoaminobenzene, p -Nitrobenzenediazonium etc. can be mentioned.

When a compound that initiates radical polymerization by the action of light is used, the coating is cured by irradiation with ionizing radiation.
Examples of such radical photopolymerization initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds , Disulfide compounds, fluoroamine compounds and aromatic sulfoniums. Examples of acetophenones include 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxydimethylphenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropiophenone and 2 -Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone is included. Examples of benzoins include benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether. Examples of the benzophenones include benzophenone, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone. Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Sensitizing dyes can also be preferably used in combination with these photoradical polymerization initiators.

  The amount of the compound that initiates radical polymerization by the action of heat or light may be an amount that can initiate polymerization of the carbon-carbon double bond, and is based on the total solid content in the low refractive index layer forming composition. 0.1-15 mass% is preferable, it is more preferable that it is 0.5-10 mass%, and it is especially preferable that it is 2-5 mass%.

(solvent)
The solvent contained in the coating composition for the low refractive index layer is not particularly limited as long as the fluorine-containing curable resin is uniformly dissolved or dispersed without causing precipitation, and two or more kinds of solvents are used in combination. You can also Preferred examples include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (ethyl acetate, butyl acetate, etc.), ethers (tetrahydrofuran, 1,4-dioxane, etc.), alcohols (methanol, ethanol, isopropyl). Alcohol, butanol, ethylene glycol, etc.), aromatic hydrocarbons (toluene, xylene, etc.), water and the like.

(Other compounds suitably contained in the coating composition for forming a low refractive index layer)
In addition, for the purpose of imparting properties such as antifouling properties, water resistance, chemical resistance, and slipping properties, known silicone-based or fluorine-based antifouling agents, slipping agents, and the like can be appropriately added. When these additives are added, it is preferably added in the range of 0 to 20% by mass of the total solid content of the low refractive index layer, more preferably in the range of 0 to 10% by mass. Particularly preferred is 0 to 5% by mass.

  The low refractive index layer can contain an inorganic filler, a silane coupling agent, a slip agent, a surfactant and the like. In particular, it is preferable to contain inorganic fine particles, a silane coupling agent, and a slip agent.

  The silane coupling agent is preferably a silane coupling agent containing a hydroxyl group, a mercapto group, a carboxy group, an epoxy group, an alkyl group, an alkoxysilyl group, an acyloxy group, or an acylamino group, and particularly preferably an epoxy group. A silane coupling agent containing a polymerizable acyloxy group ((meth) acryloyl) and a polymerizable acylamino group (acrylamino, methacrylamino).

  Particularly preferred are compounds having a (meth) acryloyl group as a crosslinkable or polymerizable functional group, such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane.

  As the slip agent, a silicone compound such as dimethyl silicone, and a fluorine-containing compound into which a polysiloxane segment is introduced are preferable.

(Formation of a low refractive index layer)
The low refractive index layer is irradiated with ionizing radiation simultaneously with application or after application / drying of a coating composition in which hollow particles, fluorine-containing curable resin, organic silyl compound and other optional components contained therein are dissolved or dispersed (for example, And light irradiation, electron beam irradiation, etc.) and are preferably cured by a crosslinking reaction by heating or a polymerization reaction.
In particular, when the low refractive index layer is formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound, the crosslinking reaction or the polymerization reaction is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less. . By forming in an atmosphere having an oxygen concentration of 10% by volume or less, an outermost layer having excellent physical strength and chemical resistance can be obtained.
The oxygen concentration is preferably 6% by volume or less, more preferably 4% by volume or less, particularly preferably 2% by volume or less, and most preferably 1% by volume or less.

As a method of reducing the oxygen concentration to 10% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.
The antireflection film of the present invention is an antireflection film having at least one low refractive index layer on a transparent support, and the low refractive index layer is formed from the polymerizable composition.

[Other layers of antireflection film]
The antireflection film may be provided with layers other than those described above. For example, an adhesive layer, a shield layer, a sliding layer, a light diffusing layer, or an antiglare layer may be provided. The shield layer is provided to shield electromagnetic waves and infrared rays.

[Production method of antireflection film, etc.]
The present invention also relates to a method for producing an antireflection film.
The method for producing an antireflection film of the present invention has a hard coat layer, a medium refractive index layer, a high refractive index layer and a low refractive index layer in this order on a transparent support, and each layer is applied, dried and cured. In which the medium refractive index layer is (A) an organic or inorganic nanoparticle having an average primary particle diameter of less than 10 nm, and (B) 3 unsaturated double bonds. A compound having at least one compound, and (C) a composition containing a polymer having a repeating unit corresponding to the monomer represented by Formula 1, wherein the polymer (C) is added to the total solid content in the composition. It is 0.2-2.0 mass% with respect to the said, or the said organic or inorganic particle (A) is 30-60 mass% with respect to the total solid in the said composition.
Each layer of the antireflection film should be coated on the transparent support by the dip coating method, air knife coating method, curtain coating method, roller coating method, die coating method, wire bar coating method, and gravure coating method. Can be formed.
Among these coating methods, in order to increase the uniformity of the coating film, it is preferable to use a gravure coating method or a die coating method.
Among the gravure coating methods, the micro gravure method is more preferable. The die coating method is particularly preferable because the film thickness control is relatively easy because it is an all-measuring method, and the evaporation of the solvent in the coating part is small. A tandem method can be employed when forming multiple layers continuously.
In the die coating method, two or more layers can be applied simultaneously. The method of simultaneous application by the die coating method is described in the specifications of US Pat. These can be used.
In the die coating method, an extrusion type or slide type die can be used alone or in combination. Of these, an extrusion die (also referred to as a slot die) is preferable. For the die design, it is preferable to use the overbiting method described in detail in paragraph numbers 0344 to 0427 of JP2003-211052A and JP2006-122889A.

(Curing treatment)
After applying the composition for forming each layer on the support as described above, a curing treatment is performed by at least one of heat and light irradiation. Thus, application | coating and a hardening process are repeated about each layer, and a hard-coat layer, a medium refractive index layer, etc. are laminated | stacked on a support body. Moreover, you may cure simultaneously all the layers which apply | coated the multilayer after simultaneous multilayer coating.
In order to suppress coloring, decomposition, and deformation of the transparent support, it is preferably 150 ° C. or lower when heat-curing, and 1000 mJ / cm ² when irradiated with light. Furthermore, it is also preferable to carry out a photocuring treatment after the heat curing treatment or heat treatment in the latter half of the photocuring treatment. In particular, in the low refractive index layer, it is preferable to carry out a photocuring treatment after the heat curing treatment or heat treatment in the latter half of the photocuring treatment.
Moreover, in order to improve the interlayer adhesion between the upper layer and the lower layer, it is preferable to half-cure the lower layer within a range that does not affect the antireflection performance and to perform full cure after the upper layer is applied.
The half-cured condition, for example, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co.), illuminance 10 to 1,000 / cm ^2, irradiation with irradiation dose of irradiation dose 10~150mJ / cm ² Can be achieved.
The Furukyua conditions after half cured, for example, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co.), illuminance 10 to 1,000 / cm ^2, irradiation amount of dose 200~800mJ / cm ² It can be achieved by irradiating with.

[Protective film for polarizing plate]
When using the antireflection film of the present invention as a polarizing film surface protective film (polarizing plate protective film), the surface of the transparent support opposite to the side having the thin film layer, that is, the surface to be bonded to the polarizing film By making it hydrophilic, it is possible to improve adhesion to a polarizing film containing polyvinyl alcohol as a main component.
Of the two protective films of the polarizer, the film other than the antireflection film is preferably an optical compensation film having an optical compensation layer comprising an optically anisotropic layer. The optical compensation film (retardation film) can improve the viewing angle characteristics of the liquid crystal display screen.
A known film can be used as the optical compensation film, but the optical compensation film described in JP-A-2001-100042 is preferable in terms of widening the viewing angle.

  When the antireflection film is used as a surface protective film for a polarizing film (protective film for polarizing plate), it is particularly preferable to use a cellulose acylate film (for example, a triacetyl cellulose film) as the transparent support.

  As a method for producing a protective film for a polarizing plate in the present invention, (1) a method of coating each layer constituting the above antireflection film on one surface of a previously saponified transparent support, and (2) a transparent support After coating an antireflection layer on one side of the body, a method of saponifying the side or both sides to be bonded to the polarizing film, (3) coating a part of the antireflection layer on one side of the transparent support Thereafter, there are three methods of applying the remaining layer after saponifying the side or both sides to be bonded to the polarizing film, (1) is hydrophilicized to the surface on which the antireflection layer is to be applied, Since it becomes difficult to ensure the adhesion between the transparent support and the antireflection layer, the method (2) is particularly preferable.

[Polarizer]
Next, the polarizing plate of the present invention will be described. The polarizing plate of the present invention is a polarizing plate having a polarizing film and two protective films for protecting both surfaces of the polarizing film, and at least one of the protective films is the antireflection film of the present invention.

  The transparent support of the antireflection film is preferably bonded to the polarizing film via an adhesive layer made of polyvinyl alcohol, if necessary, and has a protective film on the other side of the polarizing film. The surface of the other protective film opposite to the polarizing film may have an adhesive layer.

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

  Moreover, the polarizing plate of the present invention can also have an optical compensation function. In that case, only one surface side of the surface and the back surface of the two surface protective films is formed using the antireflection film, and the side having the antireflection film of the polarizing plate is the surface on the other surface side. It is preferable that the protective film is an optical compensation film.

  By producing a polarizing plate using the antireflection film of the present invention as one of the protective films for polarizing plates and an optical compensation film having optical anisotropy as the other protective film of the polarizing film, a liquid crystal display device is further produced. The contrast in the bright room and the viewing angle of the top, bottom, left and right can be improved.

  The image display device of the present invention is characterized by having the antireflection film or polarizing plate of the present invention on the outermost surface of the display.

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

[Preparation of antireflection film]
As shown below, a coating solution for forming each layer was prepared, and each layer was formed. 1-20 were produced.

((A) Synthesis of compound having quaternary ammonium base)
The ion conductive compound was carried out in the same manner as in Synthesis Example 1 of Japanese Patent No. 46006065, and the same AN-1 (30% by mass ethanol solution) as the antistatic copolymer (A-1) was synthesized.
(Preparation of coating solution for hard coat layer)
Each component was added so that it might become the composition of the coating liquid HC-1 for hard-coat layers of Table 1 below, the obtained composition was put into a mixing tank, stirred, and a polypropylene filter having a pore size of 0.4 μm To obtain an antistatic hard coat layer coating solution HC-1 (solid content: 50% by mass).

The compounds used are shown below.
AN-1: Compound AN-1 having the quaternary ammonium base
Irg. 184: Photopolymerization initiator, Irgacure 184 (manufactured by Ciba Japan Co., Ltd.)
A-TMMT: Pentaerythritol tetraacrylate (Shin Nakamura Chemical Co., Ltd. NK Ester)
FP1: A fluorine-containing leveling agent represented by the following formula

In the above structural formula, 60:40 represents a mass ratio.
(Preparation of coating liquid A for medium refractive index layer)
ZrO ₂ fine particle methyl ethyl ketone dispersion (nanouse OZ-S30K [trade name, solid content concentration: 30% by mass, average primary particle diameter of zirconium oxide fine particles: 7 nm, manufactured by Nissan Chemical Industries, Ltd.]) 6.67 parts by mass In addition, 2.86 parts by mass of pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Ester A-TMMT), leveling agent (fluorine-containing leveling agent MF represented by the following formula A, solid content concentration 30% by mass methyl ethyl ketone) Solvent) 0.17 parts by mass, photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals) 0.09 parts by mass, methyl ethyl ketone 61.72 parts by mass, methyl isobutyl ketone 9.50 parts by mass, and cyclohexanone 19 0.000 part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution A for medium refractive index layer.
Formula A

In the above formula A, 40:60 represents a mass ratio.
(Preparation of coating liquid B for medium refractive index layer)
ZrO ₂ fine particle methyl ethyl ketone dispersion SZR-K [trade name, solid content concentration: 30 mass%, average primary particle diameter of zirconium oxide fine particles: 4 nm, solvent composition: methyl ethyl ketone / methanol = 9/1 (mass ratio), Sakai Chemical Industrial Co., Ltd.] 7.50 parts by mass, 2.62 parts by mass of pentaerythritol tetraacrylate (Shin Nakamura Chemical Co., Ltd., NK Ester A-TMMT), leveling agent (fluorine-containing represented by Formula A) Leveling agent MF, solid content concentration 30% by mass methyl ethyl ketone solvent) 0.17 parts by mass, photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals) 0.08 parts by mass, methyl ethyl ketone 61.13 parts by mass, Add 9.50 parts by mass of methyl isobutyl ketone and 19.00 parts by mass of cyclohexanone and stir It was. After sufficiently stirring, the mixture was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution B for medium refractive index layer.

(Preparation of coating liquid C for medium refractive index layer)
Triazine polymer particles [solid content concentration: 15% by mass, average primary particle size of triazine polymer particles: 7 nm, solvent composition: cyclohexanone, manufactured by Nissan Chemical Industries, Ltd.] 5.83 parts by mass, pentaerythritol tetraacrylate (Shin Nakamura Chemical Co., Ltd. NK Ester A-TMMT) 1.55 parts by mass, leveling agent (fluorine-containing leveling agent MF represented by Formula A, solid content concentration 30% by mass methyl ethyl ketone solvent) 0.08 mass Part, 0.05 parts by weight of photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals), 68.19 parts by weight of methyl ethyl ketone, 9.75 parts by weight of methyl isobutyl ketone and 14.54 parts by weight of cyclohexanone And stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution C for medium refractive index layer.

(Preparation of coating liquid D for medium refractive index layer)
ZrO ₂ fine particle-containing hard coating agent OPSTA KZ6666 [trade name, solid content concentration: 50 mass%, zirconium oxide fine particle content: 70 mass% (based on solid content), average primary particle diameter of zirconium oxide fine particles: 20 nm, solvent composition: Methyl ethyl ketone / 2-butanol / xylene = 35/5 / 2.5 (mass ratio), manufactured by JSR Corporation] and 4.50 parts by mass of pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Ester A- TMMT) 2.62 parts by mass, leveling agent (fluorine-containing leveling agent MF represented by Formula A, solid content concentration 30% by mass methyl ethyl ketone solvent) 0.17 parts by mass, photopolymerization initiator (Irgacure 907, Ciba Specialty)・ Chemicals Co., Ltd.) 0.08 parts by mass, methyl ethyl ketone 64.13 parts by mass, methyl 9.50 parts by mass of ruisobutyl ketone and 19.00 parts by mass of cyclohexanone were added and stirred. After sufficiently stirring, the mixture was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution D for a medium refractive index layer.

(Preparation of coating liquid E for medium refractive index layer)
TYT80 [trade name, solid content concentration: 25 mass%, titanium oxide fine particle content: 60 mass% (based on solid content), average primary particle diameter of titanium oxide fine particles: 30 nm, solvent composition: propylene glycol monomethyl ether / methyl isobutyl ketone / Cyclohexanone = 10/45/15 (mass ratio), manufactured by Toyo Ink Mfg. Co., Ltd.] 10.00 parts by mass, pentaerythritol tetraacrylate (NK Nakamura Chemical Co., Ltd., NK Ester A-TMMT) 2.38 Parts by weight, leveling agent (fluorine-containing leveling agent MF represented by Formula A, solid content concentration 30% by weight methyl ethyl ketone solvent) 0.17 parts by weight, photopolymerization initiator (Irgacure 907, Ciba Specialty Chemicals Co., Ltd.) Manufactured) 0.08 parts by mass, methyl ethyl ketone 58.88 parts by mass, methyl isobutyl keto 9.50 parts by mass and 19.00 parts by mass of cyclohexanone were added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution E for medium refractive index layer.

(Preparation of coating liquid F for medium refractive index layer)
Except for changing pentaerythritol tetraacrylate (A-TMMT) to 1,4-butanediol diacrylate [trade name V # 195, manufactured by Osaka Organic Chemical Industry Co., Ltd.], the same as coating solution A for medium refractive index. A medium refractive index layer coating solution F was prepared.
(Preparation of coating liquid G for medium refractive index layer)
Medium refractive index layer similar to coating liquid A for medium refractive index except that pentaerythritol tetraacrylate (A-TMMT) is changed to polyethylene glycol diacrylate [trade name A-400, manufactured by Shin-Nakamura Chemical Co., Ltd.] Coating solution G was prepared.

(Preparation of coating liquid H for medium refractive index layer)
A medium refractive index layer coating liquid H was prepared in the same manner as the medium refractive index coating liquid A except that the leveling agent MF was not used.
(Preparation of coating liquid I for medium refractive index layer)
A medium refractive index layer coating solution I was prepared in the same manner as the medium refractive index coating solution A except that the leveling agent MF was changed to the leveling agent SP-15.
(Preparation of coating liquid J for medium refractive index layer)
A medium refractive index layer coating solution J was prepared in the same manner as the medium refractive index coating solution A except that the leveling agent MF was changed to the leveling agent FP-49.

(Preparation of coating liquid K for medium refractive index layer)
A medium refractive index layer coating liquid K was prepared in the same manner as the medium refractive index coating liquid A except that the amount of the leveling agent MF used was changed to 0.2% by mass (based on solid content).
(Preparation of coating liquid L for medium refractive index layer)
A medium refractive index layer coating liquid L was prepared in the same manner as the medium refractive index coating liquid A except that the amount of the leveling agent MF used was changed to 2.0% by mass (based on solid content).
(Preparation of coating liquid M for medium refractive index layer)
A medium refractive index layer coating liquid M was prepared in the same manner as the medium refractive index coating liquid A except that the amount of the leveling agent MF used was changed to 3.0% by mass (based on solid content).

(Preparation of coating liquid N for medium refractive index layer)
Except for changing pentaerythritol tetraacrylate (A-TMMT) to a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), the same as coating solution A for medium refractive index A coating solution N for medium refractive index layer was prepared.
(Preparation of coating liquid O for medium refractive index layer)
The medium refractive index layer coating liquid O was prepared in the same manner as the medium refractive index coating liquid A, except that pentaerythritol tetraacrylate (A-TMMT) was changed to urethane acrylate (trade name EB5129, manufactured by Daicel Cytec Co., Ltd.). Prepared.
(Preparation of coating liquid P for medium refractive index layer)
Coating for medium refractive index layer in the same manner as coating liquid A for medium refractive index, except that pentaerythritol tetraacrylate (A-TMMT) was changed to urethane acrylate (trade name U-4HA, Shin-Nakamura Chemical Co., Ltd.) Liquid P was prepared.

(Preparation of coating liquid Q for medium refractive index layer)
ZrO ₂ fine particle methyl ethyl ketone dispersion (nanouse OZ-S30K [trade name, solid content concentration: 30% by mass, average primary particle size of zirconium oxide fine particles: 7 nm, manufactured by Nissan Chemical Industries, Ltd.]) 3.33 parts by mass And 3.83 parts by mass of pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Ester A-TMMT), leveling agent (fluorine-containing leveling agent MF represented by the above formula A, solid content concentration 30% by mass methyl ethyl ketone) Solvent) 0.17 parts by mass, photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals) 0.12 parts by mass, methyl ethyl ketone 64.05 parts by mass, methyl isobutyl ketone 9.50 parts by mass, and cyclohexanone 19 0.000 part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution Q for a medium refractive index layer.

(Preparation of coating solution R for medium refractive index layer)
ZrO ₂ fine particle methyl ethyl ketone dispersion (nanouse OZ-S30K [trade name, solid content concentration: 30% by mass, average primary particle size of zirconium oxide fine particles: 7 nm, manufactured by Nissan Chemical Industries, Ltd.]) 10.00 parts by mass 1.89 parts by mass of pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester A-TMMT), leveling agent (fluorine-containing leveling agent MF represented by Formula A, solid content concentration 30% by mass methyl ethyl ketone) Solvent) 0.17 parts by mass, photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals) 0.06 parts by mass, methyl ethyl ketone 59.38 parts by mass, methyl isobutyl ketone 9.50 parts by mass, and cyclohexanone 19 0.000 part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution R for a medium refractive index layer.

(Preparation of coating solution S for medium refractive index layer)
ZrO ₂ fine particle methyl ethyl ketone dispersion (nanouse OZ-S30K [trade name, solid content concentration: 30% by mass, average primary particle diameter of zirconium oxide fine particles: 7 nm, manufactured by Nissan Chemical Industries, Ltd.]) 11.67 parts by mass 1.41 parts by mass of pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester A-TMMT), leveling agent (fluorine-containing leveling agent MF represented by the above formula A, solid content concentration 30% by mass methyl ethyl ketone) Solvent) 0.17 parts by mass, 0.05 parts by mass of photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals), 58.22 parts by mass of methyl ethyl ketone, 9.50 parts by mass of methyl isobutyl ketone, and cyclohexanone 19 0.000 part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution S for medium refractive index layer.

(Preparation of coating liquid A for high refractive index layer)
ZrO ₂ fine particle-containing hard coating agent (OPSTAR KZ6666 [refractive index 1.72, solid content concentration: 50 mass%, zirconium oxide fine particle content: 70 mass% (based on solid content), average particle diameter of zirconium oxide fine particles: about 20 nm, Solvent composition: methyl ethyl ketone / 2-butanol / xylene = 35/5 / 2.5 (mass ratio), manufactured by JSR Corporation]) 14.10 parts by mass, pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) NK Ester A-TMMT) 0.41 parts by mass, leveling agent (fluorine-containing leveling agent MF represented by Formula A, solid content concentration 30% by mass methyl ethyl ketone solvent) 0.11 part by mass, photopolymerization initiator (Irgacure 907) , Manufactured by Ciba Specialty Chemicals Co., Ltd.) 0.01 parts by weight, methyl ethyl ketone 48.37 parts by weight , Cyclohexanone were added and stirred 37.00 parts by weight. Filtration through a polypropylene filter having a pore diameter of 0.4 μm prepared a coating solution A for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
(Synthesis of perfluoroolefin copolymer P-1)
Perfluoroolefin copolymer P-1 was prepared in the same manner as perfluoroolefin copolymer (1) described in JP 2010-152111 A. The resulting polymer had a refractive index of 1.422.

  In the above structural formula, 50:50 represents a molar ratio.

(Preparation of hollow silica dispersion A-1)
A hollow silica particle dispersion having an average particle diameter of 60 nm, a shell thickness of 10 nm, and a silica particle refractive index of 1.31 by adjusting the conditions using the same method as dispersion A-1 described in JP-A-2007-298974. A-1 (solid content concentration 18.2 mass%) was prepared.

(Preparation of composition A-1 for forming a low refractive index layer)
The following composition was charged into a mixing tank and stirred to obtain a composition A-1 for forming a low refractive index layer (solid content concentration 5% by mass).
Perfluoroolefin copolymer P-1 14.8 parts by weight Ethyl methyl ketone 157.7 parts by weight DPHA 3.0 parts by weight Hollow silica particle dispersion A-1 21.2 parts by weight Irgacure 127 1.3 parts by weight X22- 164C 2.1 parts by mass

The compounds used are shown below.
DPHA: Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
-X22-164C: Reactive silicone (made by Shin-Etsu Chemical Co., Ltd.)
・ Irgacure 127: Photopolymerization initiator (manufactured by Ciba Japan Co., Ltd.)

(Preparation of hard coat layer A)
The coating liquid HC-1 for hard coat layer was applied on a triacetyl cellulose film (TD40UL, manufactured by FUJIFILM Corporation, refractive index 1.48) as a transparent support having a layer thickness of 40 μm using a gravure coater. . After drying at 60 ° C., an irradiance of 200 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^2. Irradiation with an irradiation amount of 50 mJ / cm ² was performed to half-cure the coating layer to form a hard coat layer A having a thickness of 10 μm.

  A medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution, which are adjusted to have a desired refractive index, are applied onto the hard coat layer A using a gravure coater. did. The refractive index of each layer was measured by applying a coating solution for each layer on a glass plate so as to have a thickness of about 4 μm, and measuring with a multiwavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.). The refractive index measured using the “DR-M2, M4 interference filter 546 (e) nm part number: RE-3523” filter was employed as the refractive index at a wavelength of 550 nm.

  The film thickness of each layer was calculated using a reflection spectral film thickness meter “FE-3000” (manufactured by Otsuka Electronics Co., Ltd.) after laminating the medium refractive index layer, the high refractive index layer, and the low refractive index layer. The value derived from the Abbe refractometer was used as the refractive index of each layer in the calculation.

The drying condition of the medium refractive index layer is 90 ° C. for 60 seconds, and the ultraviolet curing condition is a 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. And a half-curing layer having a thickness of 63 nm was formed by irradiation with an irradiance of 200 mW / cm ² and an irradiation amount of 60 mJ / cm ² .

The drying condition of the high refractive index layer is 90 ° C. for 60 seconds, and the ultraviolet curing condition is a 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. And a half-cure by irradiation with an illuminance of 200 mW / cm ² and an irradiation amount of 60 mJ / cm ² to form a high refractive index layer having a thickness of 136 nm.

(Preparation of low refractive index layer)
The low refractive index layer was dried at 60 ° C. for 60 seconds, and the ultraviolet curing condition was 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.1% by volume or less. ), And is cured by irradiation with an illuminance of 300 mW / cm ² and an irradiation amount of 300 mJ / cm ² to form a low refractive index layer having a thickness of 98 nm, a hard coat layer, a medium refractive index layer, The antireflective film was produced by applying and curing (full curing) four layers of a high refractive index layer and a low refractive index layer continuously.

  The antireflection film No. 20 was the same as No. 1 except that the transparent support of the antireflection film was changed to a sugar ester compound-containing cellulose acylate film similar to that described in Example 1 of JP2011-237764A. Was made.

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

(Saponification treatment of antireflection film)
A saponified antireflection film was also prepared for each of the produced antireflection films and tested for steel wool scratch resistance.
A 1.5 mol / l aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.01 mol / l dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The produced optical film was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C.
In this way, a saponified antireflection film was produced.

(1) Steel Wool Scratch Resistance (SW Resistance) Evaluation Using a rubbing tester, a rubbing test can be performed under the following conditions as an index of scratch resistance.
Evaluation environmental conditions: 25 ° C., 60% RH
Rubbing material: Steel wool (manufactured by Nippon Steel Wool Co., Ltd., Grade No. 0000)
Wrap around the tip (1cm x 1cm) of the scraper of the tester that comes into contact with the sample, and fix the band.
Travel distance (one way): 13cm
Rubbing speed: 13 cm / second,
Load: 200 g / cm ² ,
Tip contact area: 1 cm × 1 cm,
Number of rubs: 10 round trips.
An oily black ink was applied to the back side of the rubbed sample and visually observed with reflected light to evaluate scratches on the rubbed portion.
A: Even if you look very carefully, no scratches are visible.
B: There is no scratch, but the color is slightly changed.
C: Several scratches are visible.
D: More than a few scratches are visible.

(2) Film thickness unevenness About the antireflection film produced in the example, a sample wound in a roll shape having a width of 1340 mm was adjusted to 1100 mm width except for 120 mm at both ends in the width direction, and the film thickness was 12 at 100 mm pitch in the width direction. The film thickness is measured at 11 points every 100 m in the longitudinal direction, and the average value d (average value), minimum value d (minimum value), and maximum value d of the film thicknesses of all 132 measurement points are measured. From (maximum value), the film thickness distribution was calculated by the following mathematical formula (I).
Formula (I): (maximum value d−minimum value d) × 100 / average value d
The film thickness is optically fitted with reflection characteristics in the wavelength range of 380 to 780 nm measured from the front surface after rubbing the back surface of the antireflection film with sandpaper and then painting with black magic and eliminating the reflection on the back surface. It was calculated by doing.
A: Less than 3% B: 3% or more and less than 5% C: 5% or more

The evaluation results are shown in Table 2.
No. In the antireflection film of 11, the “present invention” is read as “reference example”.

As is clear from the results shown in Table 2, it can be seen that the antireflective films 4 and 5 of Comparative Examples in which the average primary particle diameter of the particles contained in the medium refractive index layer is 10 nm or more are inferior in SW resistance after saponification. It can be seen that the antireflection films 6 and 7 of the comparative examples in which the number of unsaturated double bonds of the compound having an unsaturated double bond is less than three are inferior in SW resistance both after unsaponification and after saponification. It turns out that the antireflection film 8 of the comparative example which does not contain the polymer (leveling agent) containing the repeating unit corresponding to the monomer represented by the general formula 1 is inferior in film thickness unevenness. The antireflection of the comparative example in which the content of the polymer containing the repeating unit corresponding to the monomer represented by the general formula 1 exceeds 2.0% by mass with respect to the total solid content in the composition for forming a medium refractive index layer It can be seen that the film 13 is inferior in SW resistance both after unsaponification and after saponification.
It can be seen that the antireflection films 17 and 19 of the comparative examples in which the content of the particles contained in the medium refractive index layer deviates from 30 to 60% by mass are inferior in SW resistance after saponification.
On the other hand, it can be seen that the antireflection films 1 to 3, 9 to 12, 14 to 16, 18 and 20 of the examples have excellent SW resistance and no film thickness unevenness both after unsaponification and after saponification.

DESCRIPTION OF SYMBOLS 1 Transparent support 2 Hard-coat layer 3 Medium refractive index layer 4 High refractive index layer 5 Low refractive index layer

Claims (10)

An antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer and a low refractive index layer in this order on a transparent support, wherein the medium refractive index layer (A) has an average primary particle diameter of less than 10 nm An organic or inorganic particle, (B) a compound having three or more unsaturated double bonds, and (C) a composition containing a polymer having a repeating unit corresponding to the monomer represented by the following general formula 1. The polymer (C) is 1.0 to 2.0% by mass with respect to the total solid content in the composition, and the organic or inorganic particles (A) are the total solid content in the composition. The antireflection film which is 30 to 60% by mass relative to the mass.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.   In the general formula 1, R _f Is -CF ₃ The antireflection film according to claim 1, which represents The antireflection film according to claim 1 or 2 , wherein the organic or inorganic particles (A) having an average primary particle diameter of less than 10 nm are zirconia particles. The numerical value of the molecular weight of pre-Symbol unsaturated double bond three or more compound having (B), a value obtained by dividing the number of functional groups, molecular weight / number of functional groups is 100 or less, any of claims 1-3 1 An antireflection film as described in the item . Wherein the transparent support is a cellulose acylate film, an antireflection film according to any one of claims 1-4. A polarizing plate having a polarizing film and two protective films protecting both surfaces of the polarizing film, wherein at least one of the protective films is the antireflection film according to any one of claims 1 to 5. Board. The antireflection film according to any one of claims 1 to 5, or an image display device having the polarizing plate according to claim 6. An antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer, and a low refractive index layer in this order on a transparent support, and each layer is formed by applying, drying and curing steps. a manufacturing method, the medium refractive index layer is (a) an organic less than the average primary particle diameter of 10nm or no opportunity particle element, (B) an unsaturated double bond compound having three or more, (C) the following general is formed from a composition containing a polymer having a repeating unit corresponding to the monomer represented by formula 1, 1.0 for the polymer (C) is the total solids in the composition to 2.0 The manufacturing method of the antireflection film which is mass% and the said organic or inorganic particle (A) is 30-60 mass% with respect to the total solid in the said composition.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a halogen atom or a methyl group.
X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R _f represents —CF ₃ or —CF ₂ H.
m represents an integer of 1 to 6.
n represents an integer of 1 to 11.   In the general formula 1, R _f Is -CF ₃ The manufacturing method of the anti-reflective film of Claim 8 showing.   The method for producing an antireflection film according to claim 8 or 9, wherein a saponification treatment is further performed after the coating, drying and curing steps.

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